Month: October 2010

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Ailmemts & Remedies

Retinitis pigmentosa

Definition:
Retinitis pigmentosa(RP) is an eye disease in which there is damage to the retinaretina. The retina is the layer of tissue at the back of the inner eye that converts light images to nerve signals and sends them to the brain.

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It is a group of genetic eye conditions that leads to incurable blindness. In the progression of symptoms for RP, night blindness generally precedes tunnel vision by years or even decades. Many people with RP do not become legally blind until their 40s or 50s and retain some sight all their lives. Others go completely blind from RP, in some cases as early as childhood. Progression of RP is different in each case.

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RP is a type of progressive retinal dystrophy, a group of inherited disorders in which abnormalities of the photoreceptors (rods and cones) or the retinal pigment epithelium (RPE) of the retina lead to progressive visual loss. Affected individuals first experience defective dark adaptation or nyctalopia (night blindness), followed by reduction of the peripheral visual field (known as tunnel vision) and, sometimes, loss of central vision late in the course of the disease.

Symptoms:
Mottling of the retinal pigment epithelium with black bone-spicule pigmentation is typically indicative (or pathognomonic) of retinitis pigmentosa. Other ocular features include waxy pallor of the optic nerve head, attenuation (thinning) of the retinal vessels, cellophane maculopathy, cystic macular edema and posterior subcapsular cataract.

Symptoms often first appear in childhood, but severe vision problems do not usually develop until early adulthood.

•Decreased vision at night or in low light
•Loss of side (peripheral) vision, causing “tunnel vision”
•Loss of centralcentral vision (in advanced cases)

Causes:
It is a group of genetic eye conditions that leads to incurable blindness. In the progression of symptoms for RP, night blindness generally precedes tunnel vision by years or even decades. Many people with RP do not become legally blind until their 40s or 50s and retain some sight all their lives. Others go completely blind from RP, in some cases as early as childhood. Progression of RP is different in each case.

RP is a type of progressive retinal dystrophy, a group of inherited disorders in which abnormalities of the photoreceptors (rods and cones) or the retinal pigment epithelium (RPE) of the retina lead to progressive visual loss. Affected individuals first experience defective dark adaptation or nyctalopia (night blindness), followed by reduction of the peripheral visual field (known as tunnel vision) and, sometimes, loss of central vision late in the course of the disease.

Retinitis pigmentosa can run in families. The disorder can be caused by a number of genetic defects.

The cells controlling night vision (rods) are most likely to be affected. However, in some cases, retinal cone cells are damaged the most. The main sign of the disease is the presence of dark deposits in the retina.

The main risk factor is a family history of retinitis pigmentosa. It is an uncommon condition affecting about 1 in 4,000 people in the United States.

Diagnosis:-
The diagnosis of retinitis pigmentosa relies upon documentation of progressive loss in photoreceptor cell function by electroretinography (ERG) and visual field testing.

The mode of inheritance of RP is determined by family history. At least 35 different genes or loci are known to cause “nonsyndromic RP” (RP that is not the result of another disease or part of a wider syndrome).

DNA testing is available on a clinical basis for:

*RLBP1 (autosomal recessive, Bothnia type RP)
*RP1 (autosomal dominant, RP1)
*RHO (autosomal dominant, RP4)
*RDS (autosomal dominant, RP7)
*PRPF8 (autosomal dominant, RP13)
*PRPF3 (autosomal dominant, RP18)
*CRB1 (autosomal recessive, RP12)
*ABCA4 (autosomal recessive, RP19)
*RPE65 (autosomal recessive, RP20)

For all other genes, molecular genetic testing is available on a research basis only.

RP can be inherited in an autosomal dominant, autosomal recessive, or X-linked manner. X-linked RP can be either recessive, affecting primarily only males, or dominant, affecting both males and females, although males are usually more mildly affected. Some digenic (controlled by two genes) and mitochondrial forms have also been described.

Tests:-
Tests to evaluate the retina:

•Color vision
•Examination of the retina by ophthalmoscopyophthalmoscopy after the pupils have been dilated
•Fluorescein angiographyFluorescein angiography
•Intraocular pressureIntraocular pressure
•Measurement of the electrical activity in the retina (electroretinogramelectroretinogram)
•Pupil reflex response
•Refraction testRefraction test
•Retinal photographyRetinal photography
•Side vision test (visual field test)
•Slit lamp examinationSlit lamp examination
•Visual acuityVisual acuity

Genetic counseling depends on an accurate diagnosis, determination of the mode of inheritance in each family, and results of molecular genetic testing.

Associations:
Retinitis pigmentosa is seen in a variety of diseases, so the differential of this sign alone, is broad.

*RP combined with deafness (congenital or progressive) is called Usher syndrome.
*RP combined with opthalmoplegia, dysphagia, ataxia, and cardiac conduction defects is seen in the mitochondrial DNA disorder Kearns-Sayre syndrome (aka Ragged Red Fiber Myopathy)
*RP combined with retardation, peripheral neuropathy, acanthotic (spiked) RBCs, ataxia, steatorrhea, is absence of VLDL is seen in abetalipoproteinemia.

Other conditions include neurosyphilis, toxoplasmosis(Emedicine “Retinitis Pigmentosa”), abetalipoproteinemia, and Refsum’s disease.

Genetics
Retinitis pigmentosa (RP) is one of the most common forms of inherited retinal degeneration. This disorder is characterized by the progressive loss of photoreceptor cells and may eventually lead to blindness.

There are multiple genes that, when mutated, can cause the Retinitis pigmentosa phenotype. In 1989, a mutation of the gene for rhodopsin, a pigment that plays an essential part in the visual transduction cascade enabling vision in low-light conditions, was identified. Since then, more than 100 mutations have been found in this gene, accounting for 15% of all types of retinal degeneration. Most of those mutations are missense mutations and inherited mostly in a dominant manner.

The rhodopsin gene encodes a principal protein of photoreceptor outer segments. Studies show that mutations in this gene are responsible for approximately 25% of autosomal dominant forms of RP.

Mutations in four pre-mRNA splicing factors are known to cause autosomal dominant retinitis pigmentosa. These are PRPF3, PRPF8, PRPF31 and PAP1. These factors are ubiquitously expressed and it is still a puzzle as to why defects in a ubiquitous factor should only cause disease in the retina.

Up to 150 mutations have been reported to date in the opsin gene associated with the RP since the Pro23His mutation in the intradiscal domain of the protein was first reported in 1990. These mutations are found throughout the opsin gene and are distributed along the three domains of the protein (the intradiscal, transmembrane, and cytoplasmic domains). One of the main biochemical causes of RP in the case of rhodopsin mutations is protein misfolding, and molecular chaperones have also been involved in RP. It was found that the mutation of codon 23 in the rhodopsin gene, in which proline is changed to histidine, accounts for the largest fraction of rhodopsin mutations in the United States. Several other studies have reported other mutations which also correlate with the disease. These mutations include Thr58Arg, Pro347Leu, Pro347Ser, as well as deletion of Ile-255. In 2000, a rare mutation in codon 23 was reported causing autosomal dominant retinitis pigmentosa, in which proline changed to alanine. However, this study showed that the retinal dystrophy associated with this mutation was characteristically mild in presentation and course. Furthermore, there was greater preservation in electroretinography amplitudes than the more prevalent Pro23His mutation.

Treatment:
Although incurable the progression of the disease can be reduced by taking some measures.
Wearing sunglasses to protect the retina from ultraviolet light may help preserve vision.

Some studies have suggested that treatment with antioxidants (such as high doses of vitamin A palmitate) may slow the disease.
Recent studies have shown that proper vitamin A supplementation can postpone blindness by up to 10 years (by reducing the 10% loss pa to 8.3% pa). However, taking high doses of vitamin A can cause serious liver problems. The benefit of treatment has to be weighed against risks to the liver.

Several clinical trials are in progress to investigate new treatments for retinitis pigmentosa, including the omega-3 fatty acid, DHA.

Microchip implants that go inside the retina and act like a microscopic video camera are in the early stages of development for treating blindness associated with this and other serious eye conditions.

It can help to see a low-vision specialist, who can help you adapt to vision loss. Make regular visits to an eye care specialist, who can detect cataractscataracts or retinal swelling — both of which can be treated.

Research on possible treatments:
Future treatments may involve retinal transplants, artificial retinal implants, gene therapy, stem cells, nutritional supplements, and/or drug therapies.

2006: Stem cells: UK Researchers working with mice, transplanted mouse stem cells which were at an advanced stage of development, and already programmed to develop into photoreceptor cells, into mice that had been genetically induced to mimic the human conditions of retinitis pigmentosa and age-related macular degeneration. These photoreceptors developed and made the necessary neural connections to the animal’s retinal nerve cells, a key step in the restoration of sight. Previously it was believed that the mature retina has no regenerative ability. This research may in the future lead to using transplants in humans to relieve blindness.

2008: Scientists at the Osaka Bioscience Institute have identified a protein, named Pikachurin, which they believe could lead to a treatment for retinitis pigmentosa.

2010: A possible gene therapy seems to work in mice.

2010:R-Tech Ueno(Japanese Medicine manufacture enterprise )Completes Phase II Clinical Study on Ophthalmic Solution UF-021 (Product Name Ocuseva (TM)) on Retinitis Pigmentosa.

Prognosis:
The disorder will continue to progress, although slowly. Complete blindness is uncommon.

Prevention:
Genetic counseling and testing may help determine whether your children are at risk for this disease.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
http://en.wikipedia.org/wiki/Retinitis_pigmentosa
http://www.nlm.nih.gov/medlineplus/ency/article/001029.htm

http://www.rwjuh.edu/health_information/adult_eye_retin.html

http://www.nlm.nih.gov/medlineplus/ency/imagepages/1094.htm

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Categories
Herbs & Plants

Bilberry

Botanical Name :Vaccinium myrtillus
Family: Vacciniaceae/Ericaceae
Genus: Vaccinium
Species: V. myrtillus
Kingdom: Plantae
Order: Ericales
Synonyms:Whortleberry. Black Whortles. Whinberry. Trackleberry. Huckleberry. Hurts. Bleaberry. Hurtleberry. Airelle. Vaccinium Frondosum. Blueberries.
Common Names:  bilberry, European blueberry, whortleberry, huckleberry

Parts Used:The ripe fruit. The leaves.

Habitat: Vaccinium myrtillus  is native to   Europe, including Britain, from Iceland south and east to Spain, Macedonia, the Caucasus and N. Asia . It grows in heaths, moors and woods on acid soils to 1250 metres.

Description:

Vaccinium myrtillus is a deciduous Shrub. It  grows abundantly in the heathy and mountainous districts, a small branched shrub, with wiry angular branches, rarely over a foot high, bearing globular wax-like flowers and black berries, which are covered when quite ripe with a delicate grey bloom, hence its name in Scotland, ‘Blea-berry,’ from an old North Countryword, ‘blae,’ meaning livid or bluish. The name Bilberry (by some old writers ‘Bulberry’) is derived from the Danish ‘bollebar,’ meaning dark berry. There is a variety with white fruits.
The leathery leaves (in form somewhat like those of the myrtle, hence its specific name) are at first rosy, then yellowish-green, and in autumn turn red and are very ornamental. They have been utilized to adulterate tea.

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Bilberries flourish best on high grounds, being therefore more abundant in the north and west than in the south and east of England: they are absent from the low-lying Cambridgeshire and Suffolk, but on the Surrey hills, where they are called ‘Hurts,’ cover the ground for miles.

The fruit is globular, with a flat top, about the size of a black currant. When eaten raw, they have a slightly acid flavour. When cooked, however, with sugar, they make an excellent preserve. Gerard tells us that ‘the people of Cheshire do eate the black whortles in creame and milke as in these southern parts we eate strawberries.’ On the Continent, they are often employed for colouring wine.

Stewed with a little sugar and lemon peel in an open tart, Bilberries make a very enjoyable dish. Before the War, immense quantities of them were imported annually from Holland, Germany and Scandinavia. They were used mainly by pastrycooks and restaurant-keepers.

Species:
Bilberries include several closely related species of the Vaccinium genus, including:

*Vaccinium myrtillus L. (bilberry)
*Vaccinium uliginosum L. (bog bilberry, bog blueberry, bog whortleberry, bog huckleberry, northern bilberry, ground hurts)
*Vaccinium caespitosum Michx. (dwarf bilberry)
*Vaccinium deliciosum Piper (cascade bilberry)
*Vaccinium membranaceum (mountain bilberry, black mountain huckleberry, black huckleberry, twin-leaved huckleberry)
*Vaccinium ovalifolium (oval-leafed blueberry, oval-leaved bilberry, mountain blueberry, high-bush blueberry).

Edible Uses:
Owing to its rich juice, the Bilberry can be used with the least quantity of sugar in making jam: half a pound of sugar to the pound of berries is sufficient if the preserve is to be eaten soon. The minuteness of the seeds makes them more suitable for jam than currants.

Recipe for Bilberry Jam—
Put 3 lb. of clean, fresh fruit in a preserving pan with 1 1/2 lb. of sugar and about 1 cupful of water and bring to the boil. Then boil rapidly for 40 minutes. Apple juice made from windfalls and peelings, instead of the water, improves this jam. To make apple juice, cover the apples with water, stew down, and strain the juice through thick muslin. Blackberries may also be added to this mixture.

If the jam is to be kept long it must be bottled hot in screw-top jars, or, if tied down in the ordinary way, more sugar must be added.

Bilberry juice yields a clear, dark-blue or purple dye that has been much used in the dyeing of wool and the picking of berries for this purpose, as well as for food, constitutes a summer industry in the ‘Hurts’ districts. Owing to the shortage of the aniline dyestuffs formerly imported from Germany, Bilberries were eagerly bought up at high prices by dye manufacturers during the War, so that in 1917 and 1918 a large proportion of the Bilberry crop was not available for jam-making, as the dyers were scouring the country for the little blue-black berries.

Wild and cultivated harvesting:-
Bilberries are found in very acidic, nutrient-poor soils throughout the temperate and subarctic regions of the world. They are closely related to North American wild and cultivated blueberries and huckleberries in the genus Vaccinium. One characteristic of bilberries is that they produce single or paired berries on the bush instead of clusters, as the blueberry does.

The fruit is smaller than that of the blueberry but with a fuller taste. Bilberries are darker in colour, and usually appear near black with a slight shade of purple. While the blueberry’s fruit pulp is light green, the bilberry’s is red or purple, heavily staining the fingers and lips of consumers eating the raw fruit. The red juice is used by European dentists to show children how to brush their teeth correctly, as any improperly brushed areas will be heavily stained.

Bilberries are extremely difficult to grow and are thus seldom cultivated. Fruits are mostly collected from wild plants growing on publicly accessible lands, notably Finland, Sweden, Norway, Iceland, Scotland, Wales, Ireland, parts of England, Alpine countries, Carpathian Mountains in Ukraine, Belarus, Romania, Bulgaria, Poland and northern parts of Turkey and Russia. Note that in Austria, Finland, Norway, Sweden and Switzerland, it is an everyman’s right to collect bilberries, irrespective of land ownership, with the exception of private gardens. Bilberries can be picked by a berry-picking rake like lingonberries, but are more susceptible to damage. Bilberries are softer and juicier than blueberries, making them difficult to transport. Because of these factors, the bilberry is only available fresh in gourmet stores, where they can cost up to 25 Euro per pound. Frozen bilberries however are available all year round in most of Europe.

In Finland, bilberries are collected from forests. They are eaten fresh or can be made in different jams, and dishes. The famous one is Mustikkapiirakka, bilberry pie

In Ireland, the fruit is known as fraughan, from the Irish fraochán, and is traditionally gathered on the last Sunday in July, known as Fraughan Sunday.

Bilberries were also collected at Lughnassadh in August, the first traditional harvest festival of the year, as celebrated by Gaelic people. The crop of bilberries was said to indicate how well the rest of the crops would fare in their harvests later in the year.

The fruits can be eaten fresh or made into jams, fools, juices or pies. In France and in Italy, they are used as a base for liqueurs and are a popular flavoring for sorbets and other desserts. In Brittany, they are often used as a flavoring for crêpes, and in the Vosges and the Massif Central bilberry tart (tarte aux myrtilles) is a traditional dessert.

Constituents:
Quinic acid is found in the leaves, and a little tannin. Triturated with water they yield a liquid which, filtered and assayed with sulphate of iron, becomes a beautiful green, first of all transparent, then giving a green precipitate.

The fruits contain sugar, etc. Bilberries contains approximately 0.5% by volume of the anthocyanosides, they also contain the vitamins B1 and C, pro-vitamin A, at least 7% by volume is composed of tannins, and assorted plant acids are also seen. The tonic effect of the anthocyanosides on the blood vessels is the beneficial to the human body.

Medicinal Uses:
Often associated with improvement of night vision, bilberries are mentioned in a popular story of World War II RAF pilots consuming bilberry jam to sharpen vision for night missions. However, a recent study by the U.S. Navy found no such effect and origins of the RAF story cannot be found.

Although the effect of bilberry on night vision is controversial, laboratory studies have provided preliminary evidence that bilberry consumption may inhibit or reverse eye disorders such as macular degeneration. A randomized, double-blind, placebo-controlled clinical trial on 50 patients suffering from senile cataract showed that a combination of bilberry extract and vitamin E administered for 4 months was able to stop lens opacity progress in 97% of the cataracts.

As a deep purple fruit, bilberries contain high levels of anthocyanin pigments, which have been linked experimentally to lowered risk for several diseases, such as those of the heart and cardiovascular system, eyes, diabetes and cancer.

In folk medicine, bilberry leaves were used to treat gastrointestinal ailments, applied topically, or made into infusions. Bilberries are also used as a tonic to prevent some infections and skin diseases.

•Historically, bilberry fruit was used to treat diarrhea, scurvy, and other conditions.

•Today, the fruit is used to treat diarrhea, menstrual cramps, eye problems, varicose veins, venous insufficiency (a condition in which the veins do not efficiently return blood from the legs to the heart), and other circulatory problems.

•Bilberry leaf is used for entirely different conditions, including diabetes.

The leaves can be used in the same way as those of UvaUrsi. The fruits are astringent, and are especially valuable in diarrhoea and dysentery, in the form of syrup. The ancients used them largely, and Dioscorides spoke highly of them. They are also used for discharges, and as antigalactagogues. A decoction of the leaves or bark of the root may be used as a local application to ulcers, and in ulceration of the mouth and throat.

The fruit is helpful in scurvy and urinary complaints, and when bruised with the roots and steeped in gin has diuretic properties valuable in dropsy and gravel. A tea made of the leaves is also a remedy for diabetes if taken for a prolonged period.
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Other Uses …..Dye; Ink…….A green dye is obtained from the leaves and the fruit and is used to colour fabrics. A blue or black dye is obtained from the fruit. This can be used as an ink.
Known Hazards: High tannin content may cause digestive disorders – avoid prolonged use or high doses. Avoid in pregnancy. Avoid if on anticoagulant therapy (e.g. warfarin)

Disclaimer:
The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplements, it is always advisable to consult with your own health care provider.

Resources:
http://www.herbs2000.com/herbs/herbs_bilberry.htm
http://botanical.com/botanical/mgmh/b/bilber37.html
http://www.elements4health.com/bilberry-health-benefits.html

http://www.pfaf.org/user/Plant.aspx?LatinName=Vaccinium+myrtillus

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