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Mar04
dentinal hypersensitivity
Dentinal Hypersensitivity

Tooth sensitivity or pain after eating cold, hot food, liquids or even breathing cold air is termed as dentinal hypersensitivity. The person may have a thought that the tooth needs to be extracted. or requires filling .However the problem of hypersensitivity can be treated very easily.

Etiology of Dentinal hypersensitivity

• Attrition
• Recession of gums
• Fractured tooth
• Post operative
• Dental caries
• Erosion of tooth surface

Person with hypersensitivity usually avoids brushing, because of pain, thus neglecting oral hygiene leading to serious problems, such as tooth decay and gum diseases. The reason why the teeth becomes hypersensitive in certain people is, when the tooth’s protective covering is absent, dentin is exposed. Dentinal tubules are open at the surface of the dentin allowing a direct channel to the nerve pulp. The dentin is normally covered by enamel or cementum. When ever the enamel or cementum is absent due to many factors like erosion, abrasion, brushing habits or a tooth defect, dentin is exposed. This exposed dentin leads to hypersensitivity.

Cause of dentinal hypersensitivity

Age
The regression of the gums as the person gets older.
Brushing habits.
Tooth enamel abrasion which may be caused by wrong brushing, by using very hard toothbrush.
Diet
Habitual ingestion of acidic food causes erosion of enamel or dentin leading to opening of dentinal tubules. The citric acid in citrus fruits dissolves enamel leading to hypersensitivity.
Tobacco
Users of tobacco regularly experience dentinal hypersensitivity. The tobacco placed between teeth and gum is known to cause gingival recession. As gingival receeds, soft gingival cementum is exposed. Continuous brushing erodes the cementum and opening the dentinal tubules.
Diseases
There is a risk of dentinal hypersensitivity in those affected with gastro esophageal reflex disease leading to increased intra oral acidity. Subsequently causing enamel erosion, leading to dental hypersensitivity.
Prevention
Following the correct brushing technique and brushing gently.
Flossing is crucial to reach tooth surfaces where brushing cannot reach.
Maintain proper oral hygiene. This will reduce gum recession and periodontal diseases
Treatment
Sensitivity tooth paste,
Fluoride mouth washes.
Filling up of hypersensitive areas.
Avoiding highly acidic food.


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Mar03
Backache in Pregnancy
Dealing With Back Pain in Pregnancy

During our prenatal exercise classes, we often ask if anyone is experiencing any physical discomforts. More often than not, the typical response is, "my lower back hurts!" How can we reduce the amount of back pain during pregnancy?

To begin with, we need to understand what is happening during pregnancy. The weight of a non-pregnant woman is centered in the middle of her pelvis. During pregnancy, the center shifts forward with the weight of the baby. Most women balance this weight by leaning back with the upper body, which increases the curve in her lower back, otherwise known as lordosis. This, coupled with the increased stress on the abdominal muscles leads to much of the discomfort she experiences.

Correcting this problem is fairly simple and requires only a few minutes and a mirror. You may notice your lower back tends to hollow inward. Pull your abdominal muscles up and in, tighten your buttocks, and press your lower back toward the wall behind you. Or, put another way, visualize your abdomen as a bowl of water. Tilt your pelvis so the "water" is level and cannot spill forward. With practice, this ?pelvic tilt? will feel comfortable and natural.

Remind yourself periodically throughout the day to check your posture and tilt your pelvis, especially if you feel tightness in your back.


There are a few other simple rules of body mechanics to remember as well:
· Wear flat or low-heeled shoes for increased comfort.
Higher heels make a pelvic tilt nearly impossible to
maintain.
· Avoid forward bending; try instead squatting or
lowering to one knee when getting up and down from
the floor or picking things up. The quadriceps muscles
in your thighs are stronger and meant for this purpose.
· Strengthen your abdominal muscles; they tend to
become less supportive during pregnancy, leading to
increased back pain. Ask your prenatal fitness
instructor or childbirth educator for a list of
appropriate abdominal exercises.
· Stretch your back! There are a variety of excellent
lower back stretches. Again, ask your instructor. Be
sure to try the pelvic tilt in the hands and knees
position.
Contract your abdominal muscles and press your middle and lower back toward the ceiling, tuck your tailbone down. When releasing this position, be sure to maintain a level spine, not allowing your back to sag or sway downward. Do these as often as necessary for relief.

· When all else fails, a back massage is a great way to relax and improve your sense of well-being!
Keep in mind that after the birth of your baby, you will still find it vital to maintain good posture, abdominal strength, and lower back flexibility. These are habits that will enable you to enjoy your baby and your body that much more!


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Mar03
Breathing Techniques in Labor
Breathing Techniques: How to Practice


Throughout all practice, remember these points:
1. There is no required breathing strategy for each
phase of labor.
2. Slow-paced breathing is best for mother and baby.
Return to it whenever possible.
3. Use relaxation skills with all breathing techniques.



Phase I--Developing Breathing Awareness

· During relaxation practice, feel your breath in your
nose, mouth, throat' then shoulders, chest, abdomen,
and back.
· Note rise and fall of chest.
· Feel the pressure of your body against a chair, bed,
pillows, and other contact areas.
· Listen to the sounds made by your breath.
· Notice changes in your breathing as you vary
positions and activities.



Phase II--Mastering Slow-Paced Breathing

· Practice with the strategy most comfortable for you.
For example, "In, 2,3,4,5, out 2,3,4,5" or listen to your
breath go in and out.
· Mentally link the ideas "release tension" and "focus"
with the initial cleansing breath.
· Practice slow-paced breathing in different positions.

Note the different sensations as you vary your position.


Phase III--Developing Strategies for Slow-Paced Breathing;

Mastering Modified-Pace Breathing
Practice slow-paced breathing by yourself using different strategies. Examples:
· Visualize breathing in a continuous circle.
· Picture energy entering your body as you breathe in
and tension leaving as you breathe out.
· As you inhale and exhale, say phrases such as "I
can give birth," "energy in, pain out," "My breath is
calm."
· Rock or walk in rhythm to your breathing.
Practice slow-paced breathing with your partner's help. Examples:
· Imagine breathing into the parts of your body where
your partner places his hands.
· Have your partner stroke down your arms or legs as
you exhale.
· Begin to practice modified-paced breathing as taught
in class, using a strategy most comfortable for you.
Vary positions and note differences in sensations.


Phase IV--Developing Strategies for Modified-Paced Breathing
Experiment with one or two strategies using modified-paced breathing. Examples:
· Breathe quietly, listen to your breath move in and out.
· Say words in rhythm, like "health-y ba-by," "be calm,"
"in, 2,3, out, 2,3."
· Use music our counting while you breathe.
· Practice patterned-paced variation as learned in
class.
· Practice with your partner, using gentle pressure
contractions rather than verbal cues.



Phase V--Mastering All Techniques
· Practice switching from one paced breathing
technique to another within the same pretend
contraction.
· Vary the length and intensity of practice
contractions.
· Practice for an early urge to push. Use a series of
light blows or a pattern of one breathe, one blow.


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Mar03
Intrauterine Growth of Baby
How Does Your Baby Grow?

Nobody can tell exactly when your baby was conceived. But fertilization usually occurs about two weeks after the beginning of your last menstrual cycle.


Within a few hours after the egg is penetrated by the sperm in the fallopian tube, the egg begins to divide. In the next three to five days, a cluster of up to 50 cells floats down the fallopian tube to the uterus, where it continues to develop. By the tenth day, the ovum is firmly implanted in the uterine wall. Here it burrows little finger-like projections called "villi" into the blood supply of the uterine lining from which it will take its nourishment... and begins the miraculous growth that will make it a real live baby.


Second Week After FertilizationAs the cluster of cells begins to elongate, a water-tight sac forms around it, gradually filling with fluid. This will serve to cushion the growing life from shocks. Next to this, a tiny yolk sac forms, preparing to produce little blood vessels. Now the placenta--the round, flat membrane that will lie inside the uterine wall--begins to develop. Joined to the umbilical cord, it will take over the job of the more primitive villi, bringing food, water and minerals from the maternal blood to the fetus, and carrying fetal waste to the blood.

Third WeekThe cell cluster is now a hollow structure filled with fluid, measuring only about 1/100 of an inch in diameter (the thickness of a heavy pencil dot). But already there are primitive lung buds...a tube that will be your baby's heart...and a thickening that is the beginning of the central nervous system. The cluster begins to curl up now so that it will fit in its compact home as it grows.

Fourth WeekA primitive face is taking form, with large circles where eyes will appear. The mouth, lower jaw, and throat are developing. Little tubules foreshadow internal organs such as the gallbladder, liver, and stomach. Blood corpuscles are taking shape, and the circulation is beginning. The tiny "heart" tube will be beating 65 times a minute by the end of this week. The embryo as it is now called, will be 3/16 of an inch in length by the end of the week. In one month, the single fertilized egg has grown 10,000 times bigger than when it started.

Fifth WeekBy the end of this week, ears begin to develop from two folds of tissue, buds emerge that will become arms and legs, and your baby's eye lenses begin taking form. There is a tiny depression where the nose will be and an equally tiny thickening that will be the tongue. Eight to ten vertebrae of the backbone have been laid down. The brain, spinal cord, and nervous system are well established. Your baby's primitive blood vessels have begun to function.

Sixth WeekBy now the beating heart can be seen with special instruments. It is still outside the baby's body, but its four chambers are beginning to form. The mouth is still closed, but the digestive tract is developing downward from the mouth cavity. By the end of the sixth week, hollows appear where eyes and ears will form; the beginnings of testes or ovaries have appeared; the brain is growing rapidly; and the entire backbone has been laid down. There is even a skeleton, though it is mostly made up of cartilage, not yet real bone. A "tail" extends from the spinal cord; at this stage, the human embryo resembles that of a pig, rabbit, or elephant. It is now 1/4 of an inch in length.


Seventh WeekThe embryo has become a fetus. Its heart is now within its chest cavity. The tail has all but disappeared. Nasal openings are breaking through. Eyes can now be perceived through closed lids. Little buds signal the beginning of fingers and toes and delicate little muscle fibers are starting. The fetus is 1/2 an inch long and weights 1/1000 of an ounce.


Eighth WeekHuman facial features, particularly the jaws, are becoming well defined. Teeth are being formed. Fingers and toes are present, and external ears form elevations on either side of the head. In boys the penis begins to appear. The fetus is no 7/8 of an inch long and weighs 1/30 of an ounce.


Ninth WeekThe baby's face is now completely formed. The clitoris appears in girls. Your baby now resembles a miniature human, slightly more than one inch in length, weighing 1/5 of an ounce.


Tenth Week: Your baby's eyes have moved from the sides of its head, where they were originally, to the front. In males, the scrotum appears. Major blood vessels have almost reached final form. The heart waves are similar to those of an adult. The baby looks top-yeavy, for the head is almost half its entire size.


End of Third Month: Upper and lower eyelids have met and fused and tear glands are starting to appear. Primitive hair follicles are forming and so are the beginnings of vocal cords. Fingernails are already present and your baby can close his fingers to make tiny fists. He can also open his mouth, purse his lips, and squint up his face. He is now three inches long, and weights about one ounce.

Fourth Month : Your baby's heartbeat is now audible to the doctor's stethoscope. Its brain looks like a miniature adult brain. Sweat glands are forming on palms and soles, and the skin is thickening into various layers. Your baby now has eyebrows and eyelashes, has grown to six ounces, and is 8 1/2 inches in length. It is at this time that many babies start to such their thumbs.

Fifth Month: Your baby's muscles are active now, and by the midpoint of pregnancy, 20 weeks, you will probably have felt "quickening"--the baby's movements. There is hair on his head. He is skinny, but fat is beginning to be deposited under his translucent skin. Twelve inches in length, he weighs about one pound.

Sixth Month: Your baby's skin is wrinkled and has developed a cheese-like protective material called "vernix" which will remain right through birth. The eyes are open and will soon be sensitive to light (although color and form won't be perceived until long after birth). Your baby can now hear sounds. And wonder of wonders--with skin ridges fully formed on palms and soles, your baby now has finger- and footprints. Length, 14 inches. Weight, 2 pounds.


Seventh Month : Fine downy hair covers your baby's body. Taste buds have developed. The male's testicles have descended into the scrotum. By the end of this month, your baby is about 16 inches long, and 3 1/2 pounds in weight. Its organ systems are now adequately well developed so that even if born prematurely, it could probably survive. But the next two months will be periods of growth and maturation to ensure a healthy entry into the world.


Eighth Month: Baby is getting plumper and plumper, and the skin is somewhat less wrinkled as fat takes up the slack. He may now weight more than five pounds, and may be some 18 inches in length. His fingernails are long, extending beyond the fingertips.


Ninth Month: The baby's skin is red but smooth. It looks polished. The only downy hair remaining now is on arms and shoulders. On the head, the hair is about one inch long. Deposit of subcutaneous fat continues. By the end of this month, what was begun from you egg cell measuring 1/200 of an inch in diameter, and your husband's sperm cell, only 1/80,000 the size of the egg, will emerge as a bouncy little infant some 20 inches in length, and weighing an average of 7 pounds.


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Mar03
Primary Infertility- A Case Study
Introduction

Primary infertility is the term used to describe a couple that has never been able to conceive a pregnancy, after at least 1 year of unprotected intercourse.
We present a case study in which PCOS (diagnosed by USG) and unovulation were thought to be the cause of primary infertility. After taking the conventional treatment for about 1 ˝ year the patient was unable to conceive. The conventional treatment was discontinued and ayurvedic treatment was given. The patient conceived in 7 months and delivered a healthy child.
The Case Report

Mrs. V. N, a 24 year old women, software engineer, married for 3 ˝ years, approached for the treatment of primary infertility. Since their marriage Mrs. V. N and her husband were staying together and were sharing a healthy sexual relationship. After one year of normal married life, as Mrs. V. N was unable to conceive, she consulted a gynecologist for advice.

The gynecologist advised routine investigations and sonography of the abdomen and ovulation study. On sonography, the ovaries were found to be polycystic and a diagnosis of PCOS was made. On ovulation study, it was observed that the ovarian follicles were not maturing, resulting into un-ovulatory cycle.

She was advised a course of Human Chorionic Gonadotrophin (HCG) 5000 i.u., i.m. in mid cycle, which she took for 12 cycles. However, even after a year of treatment, she was unable to conceive.

The gynecologist then advised her to undergo exploratory laparoscopy, which she was unwilling to undergo. At this stage she thought of ‘trying’ ayurvedic treatment.

Complaints of: Inability to conceive after 2 ˝ years of marriage

On examination: G.C - fair, Temp / Pulse / Respiration / Blood Pressure - Normal. R.S, C.V.S - Normal, Weight 51 Kg.

No history of consuming oral contraceptives or the use of any IUCD.

Menstrual history- Regular, moderate, painless

Menarche- at age 12 years

Past history of illness- Insignificant
Family history- Insignificant
No menstrual complaints of mother and elder sister

Investigations:
CBC, Blood sugar- Normal
Hystero salpingography - Normal, both tubes patent
Husband’s Semen - Normal

Treatment:

The following medicines were advised:
1.Syrup Dashmularishta1 20 ml two times a day before meals
2.Tablet Rajapravartini vati2 500 mg twice a day before lunch and dinner from day 1 to day 13 of the cycle.
3.Phala ghruta3 10 gm twice a day after breakfast and after dinner from day 14 till the next cycle.
4.Tab. Garbhapal Rasa4 250 mg twice a day after breakfast and after dinner from day 14 till the next cycle. (And throughout pregnancy)
5.Tablet Laghumalini Vasanta rasa5 250 mg twice a day after breakfast and after dinner from day 14 till the next cycle. (And throughout pregnancy)

The same treatment was continued for 7 months. No other modern medicines were given.

Result:
After about 7 months of treatment, Mrs. V.N. conceived. During the treatment period her menstrual cycles were normal. There were no other complaints. She delivered a healthy male child, weighing 2.5 kg,

Discussion:

According to ayurved, akin to the germination of a plant seed, the four most important factors for conception are 1) Rutu (season), 2) Kshetra (the field- uterus), 3) Ambu (water - nourishment) and 4) Beeja6 (seed - ovum and sperm).The probability of conception increases if all these factors are in perfect condition and in harmony with each other.

‘Rutu’, in this context, refers to the most fertile days of the menstrual cycle and the fertile age of women. ‘Kshetra’ refers to the cyclical conditioning of the uterus for making the uterine cavity most suitable for implantation of the fertilized ovum. As both these factors are associated with rhythmicity / periodicity, it is under the control of vata dosha. Also, the process of ovulation, maintaining the pregnancy till its full term and parturition are controlled by ‘apana vayu’7. Diminution of vata dosha also results in unovulation7b. Therefore, procedures (ahyanga, basti) and medicines beneficial in balancing of vata dosha, would be useful in ovulation, maintenance of pregnancy and in normal childbirth.

Nourishment of the fetus is carried out by ‘rasa’. Rasa dhatu in a pregnant women is split into three parts one nourishes the mother herself, second part is utilized to nourish the fetus and the third to produce milk8. Therefore, the medicines acting on rasa dhatu would benefit the nutrition of the fetus.

‘Beeja’ refers to both ovum and sperm. Both need to be in perfect condition for conception. The ovum is ‘agneya’9 (‘agni mahabhoota’ predominant) and shukra is ‘soumya’ (jala mahabhoota predominant). Therefore the ‘rasayana’ medicines predominant in agni mahabhoota and jala mahabhoota are beneficial for producing best quality of ‘beeja’ - ovum and sperm.

During the follicular and ovulatory phase of menstrual cycle, Rajapravartani vati, which contains ‘hinga’ (asafetida) as one of its ingredient was given to induce ovulation. As hing is ‘ati ushna veerya’ (very hot in potency, it helps the maturation and release of ovum, which is also ‘agneya’ (hot) in nature.


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Mar03
ANTIOXIDANTS IN OPHTHALMOLOGY
ANTIOXIDANTS IN OPHTHALMOLOGY
EVOLVING CONCEPTS

Prof Dr M R Jain, FAMS



ABSTRACT
As one ophthalmologist had mentioned way back a decade ago: ‘advocating antioxidants is like shooting in the dark’. It is no more now. Today the pathophysiology of free radical mediated eye degenerative diseases like age-related macular degeneration and cataract are well established, and so is the definite role of antioxidants, particularly carotenoids. As far as eye is concerned, lutein and zeaxanthin have a vital role to play, and these two carotenoids are a must for the eye to be well protected form developing macular degeneration as well as cataract. In addition, lycopene, another carotenoids has a special place in eye defense since it is the best quencher of singlet oxygen - a reactive oxygen species which causes havoc particularly in the eye.


INTRODUCTION
Free radical chemistry began in 1900s when they were determined as cause for fat spoilage. Importance of free radicals in human diseases pathophysiology was first recognized in 1969 when McCord & Fridovich isolated the first antioxidant enzyme superoxide dismutase.

The controversy as regards the use of antioxidants, particularly carotenoids, in ophthalmic diseases seems to be resolving due to advances made in measuring their levels in foods and tissues. There is consistent experimental and epidemiological evidence to substantiate the role of particularly lutein and zeaxanthin in prevention and, to a certain extent, cure of early age-related macular degeneration (ARMD) and cataract formation. Also clinical observations depending upon the recommended dietary modification and therapeutic supplementation presently are encouraging.



FREE RADICALS
DEFINITION
A free radical is defined as any species capable of independent existence and contains one or more unpaired electrons.



HOW FREE RADICALS ARE FORMED?
The various tissues in the human body are formed by innumerable molecules. Each molecule consists of two or more atoms joined together by chemical bonds. An atom, the smallest particle of an element, consists of a core which contains positively charged protons (or positrons) as well as neutral neutrons. In the orbit of each atom (referred to as orbital) are present the electrons (or negatrons). Each orbital can accommodate a maximum of two electrons both of which spin in opposite directions.

Most molecules are non-radical since they contain a paired set of electrons. But oxygen is always electronegative. As a consequence, it pulls electrons away from other atoms (including oxygen itself) and renders these as free radicals.
Oxygen-derived free radicals have a lifespan of only a few microseconds. Their concentration at any single site is miniscule. However the danger lies in their ability to combine with another nonradical to render the latter as free radical. Normally, bonds don’t split in a way that leaves a molecule with an odd, unpaired electron. But when weak bonds split, free radicals are formed. Free radicals are very unstable and react quickly with other compounds, trying to capture the needed electron to gain stability.

Fig: Serial formation of free radicals.



Generally, free radicals attack the nearest stable molecule, thereby "stealing" its electron. When the "attacked" molecule loses its electron, it becomes a free radical itself. This leads to a process of chain reaction. Once such a process has started, it can cascade, finally resulting in the disruption of a living cell.

Radicals can react with other molecules in a number of ways. If two radicals meet, they can combine their unpaired electrons symbolized by.) and join to form a covalent bond (a shared pair of electrons). The hydrogen atom, with one unpaired electron, is a radical and two atoms of hydrogen easily combine to form the diatomic hydrogen molecule:
H. + H.

Radicals react with nonradicals in several ways. A radical may donate its unpaired electron to a non-radical (a reducing radical) or it might take an electron from another molecule in order to form a pair (an oxidizing radical). A radical may also join onto a nonradical. Whichever of these three types of reaction occurs, the nonradical species becomes a radical. A feature of the reactions of free radicals with nonradicals is that they tend to proceed as chain reactions, where one radical begets another.



SOURCES OF FREE RADICALS
Some free radicals arise normally during metabolism. Sometimes the body’s cells or its immune system purposefully create them to neutralize viruses and bacteria. However, environmental factors such as pollution, radiation, cigarette smoke and herbicides can also generate free radicals. Free radicals causing structural damage (to proteins) resulting in aging changes such as cataract and ARMD.

An adult utilizes 3.5 ml oxygen per kg body weight per minute. Assuming a body weight of 70 kgs, this works out to 352.8 liters per day. Even if 1% of oxygen is converted to free radicals, this amounts to 1.72 kg of free oxygen radicals per year!



EXAMPLES SOURCES OF FREE RADICALS
Some free radicals well studied free radicals are:
• SUPEROXIDE ANION (O2.)
• HYDROXYL RADICAL (OH.)
It is important to note that free radicals such as hydroxyl radical differ from hydroxyl ions in their content of electrons.



REACTIVE OXYGEN SPECIES
These are partially reduced oxygen species which do not contain any unpaired electron. Examples of reactive oxygen species are:

• HYDROGEN PEROXIDE (H2O2)
• HYDROPEROXY RADICAL (HOO-)
• HYPOCHLOROUS ACID RADICAL (HOCl)

Under certain conditions reactive oxygen species have potential to enter free radical reactions to form the more toxic free radicals. Another reactive oxygen species, which is not a free radical, is singlet oxygen (O). In this, a rearrangement of electrons has occurred which allows it to react faster with biological molecules - as compared to ‘normal’ oxygen.



ANTIOXIDANTS
DEFINITION
Antioxidants can be defined as substances whose presence in relatively low concentrations significantly inhibits the rate of oxidation of the targets.



HOW ANTIOXIDANTS WORK?
Antioxidants serve as natural protectors in the body, mopping up free radicals and reactive oxygen species, which are potentially damaging. Antioxidants protect the tissues in 4 ways:

• Physically separating the free radicals / reactive oxygen species from the susceptible molecules of the human body.
• Providing molecules which effectively compete for oxygen.
• Rapidly repair the damage caused by free radicals / reactive oxygen species.
• Lyse the free radicals / reactive oxygen species and rapidly remove these.



CLASSIFICATION OF ANTIOXIDANTS
• ANTIOXIDANT ENZYMES
• Superoxide dismutase
• Catalase
• Glutathione peroxidase
• PREVENTIVE ANTIOXIDANTS
• Ceruloplasmin
• Transferrin
• Albumin
• CHAIN-BREAKING ANTIOXIDANTS
• Water-soluble*
• Uric acid (200-400 mmol/L)
• Ascorbate (25-100 mmol/L)
• Thiols (400-500 mmol/L)
• Bilirubin (10-20 mmol/L)
• Flavanoids
• Fat-soluble*
• Tocopherols (20-30 mmol/L)
• Ubiquinol-10 (<2 mmol/L)
• Beta-carotene (1-2 mmol/L)
• Estrogens
* optimal blood level given in brackets


The most important antioxidants are three vitamins and three minerals.

• ANTIOXIDANT VITAMINS
• CAROTENOIDS
• VITAMIN E
• VITAMIN C
• ANTIOXIDANT MINERALS
• SELENIUM
• ZINC
• MANGANESE
• COPPER




CAROTENOIDS
Carotenoids circulate in lipoproteins; 53% of beta carotene occurs in low density lipoproteins. Besides the well known beta carotene, the other carotenoids of human importance are:

• Lutein
• Zeaxanthin
• Lycopene
• Alpha carotene
• Beta cryptoxanthin

As far as the eye is concerned, Lutein and zeaxanthin are exclusively concentrated in the macula, lens and iris. The retina and choroids additionally contain lycopene, alpha- and beta carotene. In the ciliary body, all the carotenoids taken in foodstuff or as dietary supplement get accumulated.



VITAMIN E
Being a fat soluble vitamin, alpha tocopherol is abundant in all cell membranes as well as in lipoproteins. In the eye, vitamin E is present in retina and choroids, and balance in iris and ciliary body. It is important in protection of rods and cones in retina, and also for preventing free radical damage to lens. Vitamin E acts synergistically with vitamin C, beta carotene and selenium for better functioning of glutathione.



VITAMIN C
Vitamin C is protective for the cytoplasm & is also most important for plasma defense. It also occurs in certain cells like muscle, adrenals and eye. Vitamin C has the capacity to regenerate vitamin E. It is more significant in combating free radicals formed due to pollution and cigarette smoke. Vitamin C especially concentrates in ocular tissues and is the first antioxidant to tackle free radicals.



ZINC, MANGANESE & COPPER
Zinc (Zn), manganese (Mn) and copper (Cu) are constituents of superoxide dismutase (SOD) antioxidant enzyme. SOD is widely distributed in tissues as well as fluid compartments. CuZnSOD is present in cytoplasm and nucleus, MnSOD in operates mitochondria whilst CuSOD is most distributed in plasma. SOD attacks free radicals like hydroxyl radical to convert these into hydrogen peroxide.

Besides, Zn serves an important structural role, whilst Cu is necessary for functioning of another antioxidant enzyme called as catalases. Hydrogen peroxide is converted by catalases into harmless water and molecular oxygen.

In the retina, SOD plays an important role by scavenging free radicals to prevent the oxidative damage which plays a role in the development of drusen, an early sign of ARMD. Catalases, on the other hand, are vital for lens protection.


SELENIUM
Selenium (Se) is the most important dictator of glutathione peroxidase activity. Glutathione peroxidase is concentrated in various tissues, besides blood and synovial fluid. In tisues, it operates in the cytoplasm and mitochondria principally. Like catalases, glutathione peroxidase breaks down hydrogen peroxide, besides reducing lipid peroxidation like vitamin E and beta carotene.

Glutathione peroxidase and related enzymes in the retina, plus the precursor amino acids (N-acetylcysteine, L-glycine, and glutamine and selenium) are protective against damage to human retinal pigment epithelium cells. Glutathione peroxidase prevents free radical-induced apoptosis (cell suicide) and helps prevent or treat ARMD.



CAROTENOIDS
DEFINITION
More than 500 distinct compounds are today identified as naturally occurring carotenoids. They include cyclic hydrocarbon-carotenoids (carotenes), acyclic hydrocarbon carotenoids (lycopene), and oxygenated hydrocarbon carotenoids (xanthophylls like lutein and zeaxanthin).

Handelman and associates noted carotenoids concentration in the macula to be 5-fold higher compared to peripheral retina and 500 times more than the concentration in other tissues. Lutein is the major carotenoid in the peripheral retina, whereas zeaxanthin becomes more and more dominant as the foveal centre is approached. The proportion of lutein to zeaxanthin in macula is 1:2 and the proportion is reversed in the peripheral retina. The distribution of xanthophyll carotenoids suggests a possible role of lutein in protecting the rods and for zeaxanthin in protecting the cones that are concentrated in the central retina. The human lens carotenoids content is 10-20 ng/gm of wet tissue, and the ratio is 1.6:2.2 for Lutein and zeaxanthin.

Another most important dietary antioxidant of ocular significance is lycopene, which is however, conspicuous by its absence in macula. Due to its presence in high concentration in circulating blood in the eye, lycopene plays a prominent role in prevention of macular degeneration mainly by its very potent singlet oxygen quenching capacity.





FOCUS ON CAROTENOIDS IN ARMD
ARMD - INTRODUCTION
In developed countries, ARMD is the leading cause of blindness amongst the elderly (more than 60 years) with a prevalence ranging between 2 to 7% for severe (wet) form and a range of 12 to 30% for the dry form. The disease has caused irreversible visual impairment in an estimated 1.7 million Americans over the age of 65 years. The number of cases of ARMD has been predicted to increase from 2.7 million in 1970 to 7.5 million by the year 2030.

In India, the incidence of ARMD affects approximately 4-5 per cent of the population over the age of 50 years and may be affecting 19-20 per cent of people above 70 years of age. Early disease is characterized by yellowish-colored subretinal drusen. Late disease, which may be ‘dry’ or ‘wet’, may lead to significant loss of central vision. Wet form occurs only in 10 percent of population.



ARMD - PATHOPHYSIOLOGY
The light must pass the macular pigment, which contains abundance of zeaxanthin and lutein before striking the photoreceptors. If any damage to the rods and cones is to be prevented the short wave length of light rays (<500 nm range) must be filtered. This is accomplished as follows:

• 5-286 nm wavelength (ultraviolet C rays): filtered by the earth’s ozone layer.
• 286-320 nm wavelength (ultraviolet B rays): filtered by cornea.
• 320-400 nm wavelength (ultraviolet C rays): filtered by lens.
• 400-500 nm wavelength (visible blue light): filtered by lutein / zeaxanthin in macula.

The light entering the retina is between the wavelengths of 400 to 700 nm. The eye would be in perfect focus for daylight only at 560 nm, and even at night 500 nm wavelength of light is optimal for functioning of rods. Hence, filtering out 400-500 nm wavelength of light prevents damage to macula without affecting vision.
Thus macular pigments represent a significant filtering element and hence protect against the light–initiated cumulative oxidative damage. The macular pigment also removes much of the blurry, short wave blue and blue-green light that results from the eye’s chromatic aberration. Apart from this the earth’s atmosphere through which we view objects almost always contain small-suspended particles, which scatters short wave length light more than other wavelengths and results in a bluish veiling luminance.
The eye and skin are the only structures which have dual exposure to oxygen and light. In presence of blue light (400-500 nm wavelength) the oxygen will be split into singlet oxygen which is one of the most deadly reactive oxygen species as far as the eye is concerned. The blue light has potential to split molecular oxygen due to the high energy contained in it.

The singlet oxygen and other free radicals formed inside the eye initiate lipid peroxidation of photoreceptors. The polyunsaturated fatty acids in the outer membrane of rods and cones are attacked by free radicals and singlet oxygen species to result in damage of these photoreceptors. As a consequence, there is accumulation of lipofuscin by retinal pigment epithelium which then contributes in druse formation.



ARMD - MEDICAL MANAGEMENT
The damage to macula and formation of drusen can be prevented by filtering out the damaging blue light of the visible spectrum. This is possible by the macula, if its content of lutein and zeaxanthin are adequate. The additional available of lycopene in adequate amounts is of paramount importance in tackling the singlet oxygen single this carotenoids is the best antioxidant known for quenching this reactive oxygen species. In addition, glutathione peroxidase and SOD too have been shown to have preventive benefit in ARMD.



FOCUS OF CAROTENOIDS IN CATARACT
CATARACT - INTRODUCTION
Cataract is a multifactorial disease. Oxidative stress together with weakened antioxidant defense mechanism is attributed to the changes observed in human diabetic cataract. Oxidative damage to the lens has been recognized as a primary event in the pathogenesis of many forms of cataract. Consistent with this view, epidemiological reports have identified factors related to oxidative process that both increase (eg smoking and light exposure) and decrease (eg antioxidant intake) cataract risk.

Epidemiological studies provide evidence that nutritional antioxidants slow down the progression of cataract.



CATARACT - PATHOPHYSIOLOGY
Oxidative stress is high in the eye due to ultraviolet rays which promote liberation of free radicals and singlet oxygen. The epidemiological evidence to support the possibility that lutein and zeaxanthin have an important role in reducing the risk of cataract is somewhat consistent, and justifies the belief in free radical & reactive oxygen species mediated damage to the lens.

Few of the recent studies have stressed the significance of vitamin C, E and selenium in the etiology of cataract. Role of vitamin E has been more specifically stressed by several workers. Low blood levels of vitamin E are associated with approximately twice the risk of both cortical and nuclear cataracts, compared to median or high levels. Smokers are 2.6 times likely to develop posterior subcapsular cataracts more than nonsmokers. Patients with senile cataracts were found to have significantly lower blood and intraocular levels of the mineral selenium than control.



CATARACT - MEDICAL MANAGEMENT
Lower prevalence of nuclear cataract in women or men was associated with intake of lutein and zeaxanthin in high doses. Furthermore, in prospective cohort studies it was noted that people who consumed diet rich in lutein and zeaxanthin, had 20-25 percent lower risk of cataract extraction and 70 percent lower risk of cataract extraction under the age of 65 years.

Experimental study in human lens epithelial cells (HLEC) in culture was evaluated and it was concluded that addition of lycopene had a protective effect to prevent vacuolization of epithelial cells. It was observed that there was as positive effect of retardation of lens opacities due to lutein and zeaxanthin in the aging lenses.

In an 8 year prospective cohort study, Hankinson et al reported that an elevated intake of spinach, which is high in lutein and zeaxanthin (but low in beta carotene content) was most consistently associated with a lower risk of cataract extraction, whereas high beta carotene and vitamin E intakes alone had no beneficial effects against cataract prevention.

This study corroborated data from Jaques et al 1988 who demonstrated that persons with slightly elevated levels of plasma total carotenoids had a 25% lower risk for any type of cataract.



ANTIOXIDANTS IN RETINITS PIGMENTOSA
There is possibility that lutein may slow degeneration of vision in retinitis pigmentosa, a heterogeneous group of slow retinal degenerations. However, only preliminary data in a very small number of patients has been published in which lutein slowed vision loss associated with retinitis pigmentosa in one.






ANTIOXIDANTS IN DIABETIC RETINOPATHY
Several studies are in progress as regards role of antioxidants in diabetic retinopathy and glaucoma but as yet none is conclusive.



CONCLUSION
The overwhelming body of evidence points to significant beneficial effects of nutritional supplementation for most degenerative eye conditions. Important to remember is that most of the above studies used blood levels and food intakes associated with a normal diet. Taking supplements, specifically containing zeaxanthin, lutein and lycopene in adequate doses, which are theorized to provide protection to macula and lens with adequate doses, may have a much more protective effect than dietary levels alone. With so little risk, and the other potential health benefits from taking nutritional supplements, it would certainly seem prudent to try them, especially for macular degeneration where there are no real options.

Once the damage is done it cannot be reversed (except to a small degree), so prevention and early intervention is essential, especially if we have a family history of the disease. Of course, it's important to slow further progression at any stage of development. Prevention of lens and macula from the ultraviolet rays and hazard of smoking, however, needs to be over stressed.



























ANTIOXIDANTS IN OPHTHALMOLOGY
EVOLVING CONCEPTS

Prof Dr M R Jain, FAMS



ABSTRACT
As one ophthalmologist had mentioned way back a decade ago: ‘advocating antioxidants is like shooting in the dark’. It is no more now. Today the pathophysiology of free radical mediated eye degenerative diseases like age-related macular degeneration and cataract are well established, and so is the definite role of antioxidants, particularly carotenoids. As far as eye is concerned, lutein and zeaxanthin have a vital role to play, and these two carotenoids are a must for the eye to be well protected form developing macular degeneration as well as cataract. In addition, lycopene, another carotenoids has a special place in eye defense since it is the best quencher of singlet oxygen - a reactive oxygen species which causes havoc particularly in the eye.


INTRODUCTION
Free radical chemistry began in 1900s when they were determined as cause for fat spoilage. Importance of free radicals in human diseases pathophysiology was first recognized in 1969 when McCord & Fridovich isolated the first antioxidant enzyme superoxide dismutase.

The controversy as regards the use of antioxidants, particularly carotenoids, in ophthalmic diseases seems to be resolving due to advances made in measuring their levels in foods and tissues. There is consistent experimental and epidemiological evidence to substantiate the role of particularly lutein and zeaxanthin in prevention and, to a certain extent, cure of early age-related macular degeneration (ARMD) and cataract formation. Also clinical observations depending upon the recommended dietary modification and therapeutic supplementation presently are encouraging.



FREE RADICALS
DEFINITION
A free radical is defined as any species capable of independent existence and contains one or more unpaired electrons.



HOW FREE RADICALS ARE FORMED?
The various tissues in the human body are formed by innumerable molecules. Each molecule consists of two or more atoms joined together by chemical bonds. An atom, the smallest particle of an element, consists of a core which contains positively charged protons (or positrons) as well as neutral neutrons. In the orbit of each atom (referred to as orbital) are present the electrons (or negatrons). Each orbital can accommodate a maximum of two electrons both of which spin in opposite directions.

Most molecules are non-radical since they contain a paired set of electrons. But oxygen is always electronegative. As a consequence, it pulls electrons away from other atoms (including oxygen itself) and renders these as free radicals.
Oxygen-derived free radicals have a lifespan of only a few microseconds. Their concentration at any single site is miniscule. However the danger lies in their ability to combine with another nonradical to render the latter as free radical. Normally, bonds don’t split in a way that leaves a molecule with an odd, unpaired electron. But when weak bonds split, free radicals are formed. Free radicals are very unstable and react quickly with other compounds, trying to capture the needed electron to gain stability.

Fig: Serial formation of free radicals.



Generally, free radicals attack the nearest stable molecule, thereby "stealing" its electron. When the "attacked" molecule loses its electron, it becomes a free radical itself. This leads to a process of chain reaction. Once such a process has started, it can cascade, finally resulting in the disruption of a living cell.

Radicals can react with other molecules in a number of ways. If two radicals meet, they can combine their unpaired electrons symbolized by.) and join to form a covalent bond (a shared pair of electrons). The hydrogen atom, with one unpaired electron, is a radical and two atoms of hydrogen easily combine to form the diatomic hydrogen molecule:
H. + H.

Radicals react with nonradicals in several ways. A radical may donate its unpaired electron to a non-radical (a reducing radical) or it might take an electron from another molecule in order to form a pair (an oxidizing radical). A radical may also join onto a nonradical. Whichever of these three types of reaction occurs, the nonradical species becomes a radical. A feature of the reactions of free radicals with nonradicals is that they tend to proceed as chain reactions, where one radical begets another.



SOURCES OF FREE RADICALS
Some free radicals arise normally during metabolism. Sometimes the body’s cells or its immune system purposefully create them to neutralize viruses and bacteria. However, environmental factors such as pollution, radiation, cigarette smoke and herbicides can also generate free radicals. Free radicals causing structural damage (to proteins) resulting in aging changes such as cataract and ARMD.

An adult utilizes 3.5 ml oxygen per kg body weight per minute. Assuming a body weight of 70 kgs, this works out to 352.8 liters per day. Even if 1% of oxygen is converted to free radicals, this amounts to 1.72 kg of free oxygen radicals per year!



EXAMPLES SOURCES OF FREE RADICALS
Some free radicals well studied free radicals are:
• SUPEROXIDE ANION (O2.)
• HYDROXYL RADICAL (OH.)
It is important to note that free radicals such as hydroxyl radical differ from hydroxyl ions in their content of electrons.



REACTIVE OXYGEN SPECIES
These are partially reduced oxygen species which do not contain any unpaired electron. Examples of reactive oxygen species are:

• HYDROGEN PEROXIDE (H2O2)
• HYDROPEROXY RADICAL (HOO-)
• HYPOCHLOROUS ACID RADICAL (HOCl)

Under certain conditions reactive oxygen species have potential to enter free radical reactions to form the more toxic free radicals. Another reactive oxygen species, which is not a free radical, is singlet oxygen (O). In this, a rearrangement of electrons has occurred which allows it to react faster with biological molecules - as compared to ‘normal’ oxygen.



ANTIOXIDANTS
DEFINITION
Antioxidants can be defined as substances whose presence in relatively low concentrations significantly inhibits the rate of oxidation of the targets.



HOW ANTIOXIDANTS WORK?
Antioxidants serve as natural protectors in the body, mopping up free radicals and reactive oxygen species, which are potentially damaging. Antioxidants protect the tissues in 4 ways:

• Physically separating the free radicals / reactive oxygen species from the susceptible molecules of the human body.
• Providing molecules which effectively compete for oxygen.
• Rapidly repair the damage caused by free radicals / reactive oxygen species.
• Lyse the free radicals / reactive oxygen species and rapidly remove these.



CLASSIFICATION OF ANTIOXIDANTS
• ANTIOXIDANT ENZYMES
• Superoxide dismutase
• Catalase
• Glutathione peroxidase
• PREVENTIVE ANTIOXIDANTS
• Ceruloplasmin
• Transferrin
• Albumin
• CHAIN-BREAKING ANTIOXIDANTS
• Water-soluble*
• Uric acid (200-400 mmol/L)
• Ascorbate (25-100 mmol/L)
• Thiols (400-500 mmol/L)
• Bilirubin (10-20 mmol/L)
• Flavanoids
• Fat-soluble*
• Tocopherols (20-30 mmol/L)
• Ubiquinol-10 (<2 mmol/L)
• Beta-carotene (1-2 mmol/L)
• Estrogens
* optimal blood level given in brackets


The most important antioxidants are three vitamins and three minerals.

• ANTIOXIDANT VITAMINS
• CAROTENOIDS
• VITAMIN E
• VITAMIN C
• ANTIOXIDANT MINERALS
• SELENIUM
• ZINC
• MANGANESE
• COPPER




CAROTENOIDS
Carotenoids circulate in lipoproteins; 53% of beta carotene occurs in low density lipoproteins. Besides the well known beta carotene, the other carotenoids of human importance are:

• Lutein
• Zeaxanthin
• Lycopene
• Alpha carotene
• Beta cryptoxanthin

As far as the eye is concerned, Lutein and zeaxanthin are exclusively concentrated in the macula, lens and iris. The retina and choroids additionally contain lycopene, alpha- and beta carotene. In the ciliary body, all the carotenoids taken in foodstuff or as dietary supplement get accumulated.



VITAMIN E
Being a fat soluble vitamin, alpha tocopherol is abundant in all cell membranes as well as in lipoproteins. In the eye, vitamin E is present in retina and choroids, and balance in iris and ciliary body. It is important in protection of rods and cones in retina, and also for preventing free radical damage to lens. Vitamin E acts synergistically with vitamin C, beta carotene and selenium for better functioning of glutathione.



VITAMIN C
Vitamin C is protective for the cytoplasm & is also most important for plasma defense. It also occurs in certain cells like muscle, adrenals and eye. Vitamin C has the capacity to regenerate vitamin E. It is more significant in combating free radicals formed due to pollution and cigarette smoke. Vitamin C especially concentrates in ocular tissues and is the first antioxidant to tackle free radicals.



ZINC, MANGANESE & COPPER
Zinc (Zn), manganese (Mn) and copper (Cu) are constituents of superoxide dismutase (SOD) antioxidant enzyme. SOD is widely distributed in tissues as well as fluid compartments. CuZnSOD is present in cytoplasm and nucleus, MnSOD in operates mitochondria whilst CuSOD is most distributed in plasma. SOD attacks free radicals like hydroxyl radical to convert these into hydrogen peroxide.

Besides, Zn serves an important structural role, whilst Cu is necessary for functioning of another antioxidant enzyme called as catalases. Hydrogen peroxide is converted by catalases into harmless water and molecular oxygen.

In the retina, SOD plays an important role by scavenging free radicals to prevent the oxidative damage which plays a role in the development of drusen, an early sign of ARMD. Catalases, on the other hand, are vital for lens protection.


SELENIUM
Selenium (Se) is the most important dictator of glutathione peroxidase activity. Glutathione peroxidase is concentrated in various tissues, besides blood and synovial fluid. In tisues, it operates in the cytoplasm and mitochondria principally. Like catalases, glutathione peroxidase breaks down hydrogen peroxide, besides reducing lipid peroxidation like vitamin E and beta carotene.

Glutathione peroxidase and related enzymes in the retina, plus the precursor amino acids (N-acetylcysteine, L-glycine, and glutamine and selenium) are protective against damage to human retinal pigment epithelium cells. Glutathione peroxidase prevents free radical-induced apoptosis (cell suicide) and helps prevent or treat ARMD.



CAROTENOIDS
DEFINITION
More than 500 distinct compounds are today identified as naturally occurring carotenoids. They include cyclic hydrocarbon-carotenoids (carotenes), acyclic hydrocarbon carotenoids (lycopene), and oxygenated hydrocarbon carotenoids (xanthophylls like lutein and zeaxanthin).

Handelman and associates noted carotenoids concentration in the macula to be 5-fold higher compared to peripheral retina and 500 times more than the concentration in other tissues. Lutein is the major carotenoid in the peripheral retina, whereas zeaxanthin becomes more and more dominant as the foveal centre is approached. The proportion of lutein to zeaxanthin in macula is 1:2 and the proportion is reversed in the peripheral retina. The distribution of xanthophyll carotenoids suggests a possible role of lutein in protecting the rods and for zeaxanthin in protecting the cones that are concentrated in the central retina. The human lens carotenoids content is 10-20 ng/gm of wet tissue, and the ratio is 1.6:2.2 for Lutein and zeaxanthin.

Another most important dietary antioxidant of ocular significance is lycopene, which is however, conspicuous by its absence in macula. Due to its presence in high concentration in circulating blood in the eye, lycopene plays a prominent role in prevention of macular degeneration mainly by its very potent singlet oxygen quenching capacity.





FOCUS ON CAROTENOIDS IN ARMD
ARMD - INTRODUCTION
In developed countries, ARMD is the leading cause of blindness amongst the elderly (more than 60 years) with a prevalence ranging between 2 to 7% for severe (wet) form and a range of 12 to 30% for the dry form. The disease has caused irreversible visual impairment in an estimated 1.7 million Americans over the age of 65 years. The number of cases of ARMD has been predicted to increase from 2.7 million in 1970 to 7.5 million by the year 2030.

In India, the incidence of ARMD affects approximately 4-5 per cent of the population over the age of 50 years and may be affecting 19-20 per cent of people above 70 years of age. Early disease is characterized by yellowish-colored subretinal drusen. Late disease, which may be ‘dry’ or ‘wet’, may lead to significant loss of central vision. Wet form occurs only in 10 percent of population.



ARMD - PATHOPHYSIOLOGY
The light must pass the macular pigment, which contains abundance of zeaxanthin and lutein before striking the photoreceptors. If any damage to the rods and cones is to be prevented the short wave length of light rays (<500 nm range) must be filtered. This is accomplished as follows:

• 5-286 nm wavelength (ultraviolet C rays): filtered by the earth’s ozone layer.
• 286-320 nm wavelength (ultraviolet B rays): filtered by cornea.
• 320-400 nm wavelength (ultraviolet C rays): filtered by lens.
• 400-500 nm wavelength (visible blue light): filtered by lutein / zeaxanthin in macula.

The light entering the retina is between the wavelengths of 400 to 700 nm. The eye would be in perfect focus for daylight only at 560 nm, and even at night 500 nm wavelength of light is optimal for functioning of rods. Hence, filtering out 400-500 nm wavelength of light prevents damage to macula without affecting vision.
Thus macular pigments represent a significant filtering element and hence protect against the light–initiated cumulative oxidative damage. The macular pigment also removes much of the blurry, short wave blue and blue-green light that results from the eye’s chromatic aberration. Apart from this the earth’s atmosphere through which we view objects almost always contain small-suspended particles, which scatters short wave length light more than other wavelengths and results in a bluish veiling luminance.
The eye and skin are the only structures which have dual exposure to oxygen and light. In presence of blue light (400-500 nm wavelength) the oxygen will be split into singlet oxygen which is one of the most deadly reactive oxygen species as far as the eye is concerned. The blue light has potential to split molecular oxygen due to the high energy contained in it.

The singlet oxygen and other free radicals formed inside the eye initiate lipid peroxidation of photoreceptors. The polyunsaturated fatty acids in the outer membrane of rods and cones are attacked by free radicals and singlet oxygen species to result in damage of these photoreceptors. As a consequence, there is accumulation of lipofuscin by retinal pigment epithelium which then contributes in druse formation.



ARMD - MEDICAL MANAGEMENT
The damage to macula and formation of drusen can be prevented by filtering out the damaging blue light of the visible spectrum. This is possible by the macula, if its content of lutein and zeaxanthin are adequate. The additional available of lycopene in adequate amounts is of paramount importance in tackling the singlet oxygen single this carotenoids is the best antioxidant known for quenching this reactive oxygen species. In addition, glutathione peroxidase and SOD too have been shown to have preventive benefit in ARMD.



FOCUS OF CAROTENOIDS IN CATARACT
CATARACT - INTRODUCTION
Cataract is a multifactorial disease. Oxidative stress together with weakened antioxidant defense mechanism is attributed to the changes observed in human diabetic cataract. Oxidative damage to the lens has been recognized as a primary event in the pathogenesis of many forms of cataract. Consistent with this view, epidemiological reports have identified factors related to oxidative process that both increase (eg smoking and light exposure) and decrease (eg antioxidant intake) cataract risk.

Epidemiological studies provide evidence that nutritional antioxidants slow down the progression of cataract.



CATARACT - PATHOPHYSIOLOGY
Oxidative stress is high in the eye due to ultraviolet rays which promote liberation of free radicals and singlet oxygen. The epidemiological evidence to support the possibility that lutein and zeaxanthin have an important role in reducing the risk of cataract is somewhat consistent, and justifies the belief in free radical & reactive oxygen species mediated damage to the lens.

Few of the recent studies have stressed the significance of vitamin C, E and selenium in the etiology of cataract. Role of vitamin E has been more specifically stressed by several workers. Low blood levels of vitamin E are associated with approximately twice the risk of both cortical and nuclear cataracts, compared to median or high levels. Smokers are 2.6 times likely to develop posterior subcapsular cataracts more than nonsmokers. Patients with senile cataracts were found to have significantly lower blood and intraocular levels of the mineral selenium than control.



CATARACT - MEDICAL MANAGEMENT
Lower prevalence of nuclear cataract in women or men was associated with intake of lutein and zeaxanthin in high doses. Furthermore, in prospective cohort studies it was noted that people who consumed diet rich in lutein and zeaxanthin, had 20-25 percent lower risk of cataract extraction and 70 percent lower risk of cataract extraction under the age of 65 years.

Experimental study in human lens epithelial cells (HLEC) in culture was evaluated and it was concluded that addition of lycopene had a protective effect to prevent vacuolization of epithelial cells. It was observed that there was as positive effect of retardation of lens opacities due to lutein and zeaxanthin in the aging lenses.

In an 8 year prospective cohort study, Hankinson et al reported that an elevated intake of spinach, which is high in lutein and zeaxanthin (but low in beta carotene content) was most consistently associated with a lower risk of cataract extraction, whereas high beta carotene and vitamin E intakes alone had no beneficial effects against cataract prevention.

This study corroborated data from Jaques et al 1988 who demonstrated that persons with slightly elevated levels of plasma total carotenoids had a 25% lower risk for any type of cataract.



ANTIOXIDANTS IN RETINITS PIGMENTOSA
There is possibility that lutein may slow degeneration of vision in retinitis pigmentosa, a heterogeneous group of slow retinal degenerations. However, only preliminary data in a very small number of patients has been published in which lutein slowed vision loss associated with retinitis pigmentosa in one.






ANTIOXIDANTS IN DIABETIC RETINOPATHY
Several studies are in progress as regards role of antioxidants in diabetic retinopathy and glaucoma but as yet none is conclusive.



CONCLUSION
The overwhelming body of evidence points to significant beneficial effects of nutritional supplementation for most degenerative eye conditions. Important to remember is that most of the above studies used blood levels and food intakes associated with a normal diet. Taking supplements, specifically containing zeaxanthin, lutein and lycopene in adequate doses, which are theorized to provide protection to macula and lens with adequate doses, may have a much more protective effect than dietary levels alone. With so little risk, and the other potential health benefits from taking nutritional supplements, it would certainly seem prudent to try them, especially for macular degeneration where there are no real options.

Once the damage is done it cannot be reversed (except to a small degree), so prevention and early intervention is essential, especially if we have a family history of the disease. Of course, it's important to slow further progression at any stage of development. Prevention of lens and macula from the ultraviolet rays and hazard of smoking, however, needs to be over stressed.


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Mar02
Modified Transpalatal Arch (M-TPA) For Intrusion Of Maxillary 2nd Molar
INTRODUCTION:
Intrusion of extruded maxillary second molar has always been a challenging situation in orthodontics. Extrusion of second molar/s is commonly seen when the opposing tooth is missing due to extraction or congenital absence. It leads to occlusal plane problems and occasionally buccal tilting of second molars. Sometimes it is also seenin cases of a complete ope bite, with occlusal contacts in second molar region only.
An attempt to level the extruded maxillary second molars by using fixed orthodontic appliance involving the second molars with a continuous arch wire leads to extrusion of teeth anterior to the second molars rather than its intrusion. It results in opening of mandibular plane angle, and downward and backward rotation of mandible. It is detrimental esp in cases of vertical growth pattern and skeletal class II cases.
Some clinicians tend to equilibrate the occlusal surface of extruded maxillary second molar to level it. It may be a method of choice in mild extrusion cases, but in other cases, the tooth may require intentional root canal treatment, reduction of crown and then placing jacket crown, thus jeopardising the long life of the tooth.
To solve this problem, we have successfully used a modified form of transpalatal arch (M-TPA) to apply isolated intrusive forces on the extruded maxillary second molar only. The anchorage is obtained by M-TPA and involving the other teeth in a continuous arch wire from first permanent molar of one side to other side.
FABRICATION OF M-TPA:
A double buccal tube having a headgear tube is used on the maxillary first molar bands and the bands are then taken in a pick-up impression, and a working cast is made in plaster of paris. M-TPA is made in 0.9 – 1.0 mm hard stainless steel round wire. Its distal ends are bent in the form of hooks adapted along the palatal curvature; approx 2 mm away from the palatal tissues, and extending around 6 – 8 mm from the free gingival margins. It is then soldered on thefirst molar bands taken in the pick-up impression, (FIGS.). Another hook of the same wire is made extending approx. 4 - 6 mm from free gingival margin avoiding the active vestibular depth on buccal side, which is adapted in relation to the extruded maxillary second molar on buccal side. It is inserted in the headgear tube from the distal opening and soldered there. It may be done for both the sides if required. This assembly is now cemented in place on the maxillary first molars with light cured glass ionomer cement.
These two hooks on M-TPA can now be used for engaging elastic or E-chain, crossing over the occlusal surface of extruded maxillary second molar, (FIGS.). The forces are now concentrated on extruded maxillary second molar only. The forces required can be achieved by adjusting the length of E-chain or size of the elastics. A lingual button or a Beggs’ bracket or other bracket can be bonded on the occlusal surface of extruded maxillary second molar to avoid slippage of the E-chain, which otherwise may lead to gingival trauma if it gets slipped in the proximal side of the extruded maxillary second molar. Elastics are to be changed everyday which require patient’s cooperation, so E-chain is a better option.
Adequate intrusion of extruded maxillary second molar can be achieved within 3 – 4 months. A palatally – directed force from the E-chain may also lead to correction of buccal inclination of the second molar. After intrusion ,the second molars can now be incorporated in the continuous arch wire with other teeth, by placing buccal tube in proper position. It will help in prevention of the relapse of the intrusion. However, a light intrusiove force must be continued on the corrected maxillary second molar with the help of E-chain as before to avoid relapse for at least 3 -4 months more.
CONCLUSION:
M-TPA is an inexpensive and effective appliance for intrusion of extruded maxillary second molars. It helps to apply isolated forces on the extruded maxillary second molar, without disturbing anchorage teeth and causing any ill – effects on the dentition.


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Feb27
What are vascular diseases
What are vascular diseases and Vascular Surgery

“A surgeon's skills are measured by the way he handles the blood vessels”

These prophetic words of the great American surgeon William Halstead ushered in the era of one of the most skilful surgical specialties – Peripheral Vascular Surgery. This field has rapidly evolved over the last hundred years, with major advances occurring during the II World war and the Korean war. Endovascular interventions in the form of angioplasty and stenting have added an exciting new dimension for treatment of vascular diseases in the last two decades.

Vascular bypass operations in the leg preceded “heart bypass” operations by many years!

Vascular and Endovascular Surgery is a highly specialized field that deals with all the blood vessels in the body except those in the heart and the brain. Arteries that carry oxygenated blood from the heart to various organs and veins that return deoxygenated blood back to the heart, are the two main forms of blood vessels whose diseases are addressed by vascular surgeon. They are the life-lines of various body parts.The expression of vascular problems in different parts of the body is quite variable and this makes the specialty a complex, challenging field. A vascular surgeon is truly a “vascular specialist” since his expertise encompasses not only surgery, but also newer minimally invasive endovascular procedures (angioplasty, stenting) and vascular medicines. Hence vascular surgery remains one of the few “holistic” medical fields today which delivers complete, seamless care to patients with vascular disease.

How much is the problem?

What would be the magnitude of peripheral arterial disease of the legs in India? Since there are no specific data, we could extrapolate the available data to Indian population and the numbers thus obtained are quite staggering:

• Among 42 million diabetics – about 1000 per million will develop Critical Limb Ischemia, which usually means if some vascular procedure is not done they will lose the leg, which also makes them high risk for heart attack or stroke. If untreated this amounts to 42,000 amputations per year!
• Among rest of the population – about 500 per million (about 4,85,000) will develop critical limb ischemia needing a vascular correction or amputation!!
• In rest of the population about 38,00,000 (about 380 per 1,00,000 population) will develop peripheral vascular disease – these are the patients whose future vascular events can brought down significantly if proper medical care is given.

Venous diseases are far more common and include varicose veins, venous ulcers and deep vein thrombosis. All these problems affect a person’s quality of life and deep vein thrombosis is potentially life-threatening.

Causative factors
1. Smoking
2. Diabetes mellitus
3. High cholesterol
4. Lack of exercise
5. Obesity
6. Thrombophilia: tendency for blood to clot easily.
7. Heredity
8. Aging

Symptoms of vascular disease

Majority of vascular patients have one or more of the following three symptoms:

1. Painful extremity
2. Swollen extremity
3. Ulcerated extremity
Other problems include arterial aneurysms (dilated arteries) that have a potential for rupture, renovascular hypertension that is correctible, mesenteric ischemia that reduces blood supply to the intestines and has a higher fatality that heart attack, carotid artery stenosis that affects blood supply to the brain and results in paralytic attack which is preventable!
There has been an exponential increase of vascular problems in India due to unabated smoking and rapid increase in diabetic population (42 million or 4.2 crores), crossing all economic barriers. Peripheral vascular disease affects mostly the legs, which initially causes pain in the calf muscles while walking. The walking distance progressively reduces and if ignored will result in severe pain in the toes even at rest and eventually will result in gangrene of the toes and the foot, which might necessitate amputation. This “leg attack” is more dangerous than heart attack as it can endanger the limb and life of the patient. But this can be easily treated in the initial stages with appropriate medicines and simple life style modification programs. Unfortunately, these patients rarely reach a qualified vascular surgeon at this stage. One of the main reasons being lack of awareness among the public and also among many of the doctors about the vascular diseases and the role of vascular surgeon. There are only about 50 vascular surgeons in India, which results in these patients seen by other specialists, resulting in delayed referral to a vascular surgeon. In fact majority of these patients are not seen by vascular surgeon at all resulting in unnecessary limb and life loss. Even when a patient presents relatively late to a vascular surgeon, most of the limbs can be salvaged with a high success and low complication rate by vascular bypass or minimally invasive endovascular procedures like angioplasty and stenting if needed.

Blocked arteries in the leg mirrors rest of the body. Early diagnosis by good clinical examination and simple tests in patients with risks (smokers, diabetics, those over 50 years) will detect the disease even before they become symptomatic. It is well established now decreased blood flow in the legs is the biggest indicator of future hear attacks, strokes and amputation of legs or in other words the blocked arteries in the legs indicate a wide spread vascular disease in the body. When a patient has blocked arteries in the heart (cause of heart attack) it indicates that there is 30% chance that he/she has vascular disease else where, but a blocked artery in the leg indicates 60 to70% chance of diffuse vascular disease. Hence it is recommended in these risks groups should be examined peripheral arterial disease in the legs and if they do, they should be started on good medical treatment and life style modification program, which would markedly decrease the chance of future heart attacks, stroke or amputations.


Since poorly diagnosed and untreated vascular disease can lead to major limb and life threatening problems, it is of paramount importance that public and the medical profession is aware of early symptoms and the diagnostic methods. Early diagnoses and proper therapy will not only control the disease, but will markedly decrease the future complications and results in improved quality of life.

Vascular surgeon plays a pivotal role in diagnosing and treating these diseases, as our medical education imparts very little knowledge about vascular diseases to other specialties. Hence it is mandatory that any body suspected of these problems be evaluated by a vascular surgeon.

Patients with diabetic foot problems, which are the number one cause of admission in diabetic patients in India, usually are treated by vascular surgeon. These are of epidemic proportions, causing life and limb loss, though they can be easily prevented with proper foot care. Vascular surgeon plays a pivotal role in caring for the diabetic foot problems whether they are related to vasculopathy or neuropathy.

Vascular surgeon’s field is wide since it covers major portion of the human body. The next most important disease treated is stroke prevention surgery. Majority of strokes occur because of the narrowing of a blood vessel, called carotid artery, in the neck which carries blood to the brain. If diagnosed in time and treated with a highly successful surgical procedure called “Carotid Endarterectomy”, the chances of stroke is markedly reduced. In few, highly selected patients vascular surgeon may opt to perform “angioplasty and stenting”, but these cannot be applied to all patients at present, but might change in future. Again, it important to have these patients evaluated by a vascular surgeon, for proper diagnosis and treatment.

Vascular surgeons also deals with blood vessels in the upper limbs, those inside the abdomen supplying vital organs like the kidneys, liver intestines etc. Diseases of the veins, simplest of which is the varicose veins, also come under the purview of vascular surgeon.


Dr. P C Gupta, MS, FICA
Senior Consultant & Chief,
Vascular & Endovascular Surgery

Watch this space for disease specific articles.


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Feb27
Biochemic way is the simplest way
There are many theories and practices of allopathic and alternative medicine all over the world and of all the theories in history, there are few that are as simple, appealing and rational as the treatment of ailments by means of the inorganic cell-salts that are naturally occurring in the human body. If living a healthly life is important to you, then the investigation of the cell salts is crucial.



The key function of the12 cell salts (also known as tissue salts, Biochemic salts, Schuessler Salts and inorganic salts) is to build cell substance out of organic material. They serve as the active agent for this purpose. Although often thought of as homeopathic medicines, tissue salts are also referred to as a “Biochemic Therapy” because they are used to treat “mineral deficiencies” or “mineral imbalances” in the body. In contrast, homeopathy is based on the treatment of symptoms using the “law of similars”. Tissue salts are homeopathically prepared so they are very easy for the body to assimilate.



Historically, cell salts were thought to be of little importance because they only make up about five percent of our body composition. Practitioners today, however, understand more about cell salt functionality and how they contribute to overall health and well being throughout the body.


Cell Salts can be used for everyday acute situations by rebalancing minerals throughout the deficient body parts. Effective for children, adults, and pets and depending on the situation can be used more long term for healing. Think of the tissue salts as brick layers of the body while all the organic material ingested can be considered brick. Even if you have great BRICK going into the body, without adequate brick layers, bodily functions are not optimized.


If anyone doubts the cell salt effectiveness, just think of Mag Phos for cramping. If experiencing cramps of any type Mag Phos settles the problem usually within minutes.


With my own experience which started with myself feeling the effect of Magnesia Phos for cramps, I started study in the Biochemic system and have found the results very fruitful and treated many a cases of emergency where the patient was advised to be hospitablized but the very next day the same was working normally.


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Feb26
Approach to Homeopath
When you approach to Homeopath for treatment should go with all your previous investigation reports , prescription which are taken before . these are important for diagnosis and prognosis of a disease.
Another thing is very important , Case taking . You should take an appointment to visit a Homeopath . In chronic case it takes up to two hour for case taking . During case taking Homeopath ask you a lot of questions to analyse you physically and mentally to make a prescription .
This would include the questions about your personality and temperament , how you react to environment factors . appetite , craving , your thirst , perspiration , sleep , dreams , past history of illness , Family history . these are very important for arriving to proper remedy .
mental symptoms are very important so you have to told in detail . your nature, anger , reaction , irritablity, any incidence in life it make hurt you . From that Homeopath analyse you mentally. It is better to come with your close relative or friend to add something regarding your nature , sometimes it helps much .
After this long history , Homeopath workout your case it takes sometime and give a medicine.
Along with medicine Homeopath advised Diet , lifestyle , exercise , asked to leave addiction .
* some precautions to take while treatment .*
1) Tongue should be clean while taking medicine , don't take 15 mints. before and after medicine.
2) Generally avoid any other medicine for acute complaints , contact to Homeopath.
3) To cut down all addictions , tobacco, alcohol , smoking, etc.
4)Medicine will taken in paper or spoon and not in the hand .
5) Medicine are to be stored in cool , dry place , away from strong odours,and especially away from camphor. camphor interfere the action of Homeopathic medicines.


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