Categories
Herbs & Plants

Ophrys apifera

 

Botanical Name: Ophrys apifera
Family: Orchidaceae
Genus: Ophrys
Order: Asparagales
Species: O. apiferay
Species: O. apifera
Kingdom: Plantae

Common Name: Bee orchid

Habitat : Ophrys apifera is native to Central and southern Europe, including Britain, to N. Africa . It generally grows on semi-dry turf, in grassland, on limestone, calcareous dunes or in open areas in woodland, also on base-rich clays and calcareous dunes. It prefers calcareous soils, in bright light or dim light.

Description:
Ophrys apifera is a perennial herbaceous orchid plant. It grows to a height of 15–50 centimetres (6–20 in). This hardy orchid develops small rosettes of leaves in autumn. They continue to grow slowly during winter. Basal leaves are ovate or oblong-lanceolate, upper leaves and bracts are ovate-lanceolate and sheathing. The plant blooms from mid-April to July producing a spike composed from one to twelve flowers. The flowers have large sepals, with a central green rib and their colour varies from white to pink, while petals are short, pubescent, yellow to greenish. The labellum is trilobed, with two pronounced humps on the hairy lateral lobes, the median lobe is hairy and similar to the abdomen of a bee. It is quite variable in the pattern of coloration, but usually brownish-red with yellow markings. The gynostegium is at right angles, with an elongated apex...CLICK  &  SEE  THE PICTURES
Cultivation:
Plants can be grown in a lawn, but the lawn must not be cut until the plants have set seed. When well-suited, the plants can multiply rapidly. Grows well in a sunny dry border or on a scree. Orchids are, in general, shallow-rooting plants of well-drained low-fertility soils. Their symbiotic relationship with a fungus in the soil allows them to obtain sufficient nutrients and be able to compete successfully with other plants. They are very sensitive to the addition of fertilizers or fungicides since these can harm the symbiotic fungus and thus kill the orchid. This symbiotic relationship makes them very difficult to cultivate, though they will sometimes appear uninvited in a garden and will then thrive. Transplanting can damage the relationship and plants might also thrive for a few years and then disappear, suggesting that they might be short-lived perennials. This species can often appear in disturbed habitats well away from its normal preferred sites on chalk and limestone hills. The flowers resemble a female insect and also emit a scent similar to female pheremones. This species is unique in the genus, however, in that it is not pollinated by insects but is self-pollinated. Tubers should be planted out whilst they are dormant, this is probably best done in the autumn. They should be planted at least 5cm below soil level.
Propagation :
Seed – surface sow, preferably as soon as it is ripe, in the greenhouse and do not allow the compost to dry out. The seed of this species is extremely simple, it has a minute embryo surrounded by a single layer of protective cells. It contains very little food reserves and depends upon a symbiotic relationship with a species of soil-dwelling fungus. The fungal hyphae invade the seed and enter the cells of the embryo. The orchid soon begins to digest the fungal tissue and this acts as a food supply for the plant until it is able to obtain nutrients from decaying material in the soil. It is best to use some of the soil that is growing around established plants in order to introduce the fungus, or to sow the seed around a plant of the same species and allow the seedlings to grow on until they are large enough to move. This species only rarely forms new offsets and so division is seldom feasible, the following methods can be tried, however. Division of the tubers as the flowers fade. This species produces a new tuber towards the end of its growing season. If this is removed from the plant as its flowers are fading, the shock to the plant can stimulate new tubers to be formed. The tuber should be treated as being dormant, whilst the remaining plant should be encouraged to continue in growth in order to give it time to produce new tubers. Division can also be carried out when the plant has a fully developed rosette of leaves but before it comes into flower. The entire new growth is removed from the old tuber from which it has arisen and is potted up, the cut being made towards the bottom of the stem but leaving one or two roots still attached to the old tuber. This can often be done without digging up the plant. The old tuber should develop one or two new growths, whilst the new rosette should continue in growth and flower normally

Edible Uses:     Root – cooked. It is a source of ‘salep‘, a fine white to yellowish-white powder that is obtained by drying the tuber and grinding it into a powder. Salep is said to be very nutritious and is made into a drink or added to other cereals and used in bread etc. One ounce of salep is said to be enough to sustain a person for a day. The salep can also be made into a drink.

Medicinal Uses:    Demulcent; Nutritive.
Salep is very nutritive and demulcent. It has been used as a diet of special value for children and convalescents, being boiled with water, flavoured and prepared in the same way as arrowroot. Rich in mucilage, it forms a soothing and demulcent jelly that is used in the treatment of irritations of the gastro-intestinal canal. One part of salep to fifty parts of water is sufficient to make a jelly. The tuber, from which salep is prepared, should be harvested as the plant dies down after flowering and setting seed.

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

Resources:
http://www.pfaf.org/user/Plant.aspx?LatinName=Ophrys+apifera
https://en.wikipedia.org/wiki/Ophrys_apifera

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Categories
Herbs & Plants

Ophrys araneola

 

 

Botanical Name: Ophrys araneola
Family: Orchidaceae
Subfamily: Orchidoideae
Genus: Ophrys
Species: O. sphegodes
Kingdom: Plantae
Order: Asparagales

Habitat : Ophrys araneola is native to S. and C. Europe.
Description:
Ophrys araneola is a parennial orchid plant, growing to 0.5 m (1ft 8in). It is in flower from Apr to June. The flowers are hermaphrodite (have both male and female organs) and are pollinated by Insects....CLICK & SEE THE PICTURES
Cultivation:
Plants can be grown in a lawn, but the lawn must not be cut until the plants have set seed. Orchids are, in general, shallow-rooting plants of well-drained low-fertility soils. Their symbiotic relationship with a fungus in the soil allows them to obtain sufficient nutrients and be able to compete successfully with other plants. They are very sensitive to the addition of fertilizers or fungicides since these can harm the symbiotic fungus and thus kill the orchid. This symbiotic relationship makes them very difficult to cultivate, though they will sometimes appear uninvited in a garden and will then thrive. Transplanting can damage the relationship and plants might also thrive for a few years and then disappear, suggesting that they might be short-lived perennials. The flowers resemble a female insect and also emit a scent similar to female pheremones, they are pollinated by a male insect of that species attempting to copulate with the flower. Tubers should be planted out whilst they are dormant, this is probably best done in the autumn. They should be planted at least 5cm below soil level.
Propagation:
Seed – surface sow, preferably as soon as it is ripe, in the greenhouse and do not allow the compost to dry out. The seed of this species is extremely simple, it has a minute embryo surrounded by a single layer of protective cells. It contains very little food reserves and depends upon a symbiotic relationship with a species of soil-dwelling fungus. The fungal hyphae invade the seed and enter the cells of the embryo. The orchid soon begins to digest the fungal tissue and this acts as a food supply for the plant until it is able to obtain nutrients from decaying material in the soil. It is best to use some of the soil that is growing around established plants in order to introduce the fungus, or to sow the seed around a plant of the same species and allow the seedlings to grow on until they are large enough to move. This species only rarely forms new offsets and so division is seldom feasible, the following methods can be tried, however. Division of the tubers as the flowers fade. This species produces a new tuber towards the end of its growing season. If this is removed from the plant as its flowers are fading, the shock to the plant can stimulate new tubers to be formed. The tuber should be treated as being dormant, whilst the remaining plant should be encouraged to continue in growth in order to give it time to produce new tubers. Division can also be carried out when the plant has a fully developed rosette of leaves but before it comes into flower. The entire new growth is removed from the old tuber from which it has arisen and is potted up, the cut being made towards the bottom of the stem but leaving one or two roots still attached to the old tuber. This can often be done without digging up the plant. The old tuber should develop one or two new growths, whilst the new rosette should continue in growth and flower normally
Edible Uses:
Root – cooked. It is a source of ‘salep‘, a fine white to yellowish-white powder that is obtained by drying the tuber and grinding it into a powder[200]. Salep is said to be very nutritious and is made into a drink or added to other cereals and used in bread etc[183]. One ounce of salep is said to be enough to sustain a person for a day[100, 115]. The salep can also be made into a drink

Medicinal Uses:
Demulcent; Nutritive.

Salep is very nutritive and demulcent. It has been used as a diet of special value for children and convalescents, being boiled with water, flavoured and prepared in the same way as arrowroot. Rich in mucilage, it forms a soothing and demulcent jelly that is used in the treatment of irritations of the gastro-intestinal canal. One part of salep to fifty parts of water is sufficient to make a jelly. The tuber, from which salep is prepared, should be harvested as the plant dies down after flowering and setting seed

Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.
Resources:
https://commons.wikimedia.org/wiki/Ophrys_araneola
http://www.pfaf.org/user/Plant.aspx?LatinName=Ophrys+araneola

Categories
Herbs & Plants

Trichosanthes kirilowii

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Botanical Name :Trichosanthes kirilowii
Family: Cucurbitaceae
Genus: Trichosanthes
Species:T. kirilowii
Kingdom:Plantae
Order:Cucurbitales

Common Names:  Chinese cucumber in English. And Chinese snake gourd.

Habitat :Trichosanthes kirilowii found particularly in Henan, Shandong, Hebei, Shanxi, and Shaanxi. It is one of the 50 fundamental herbs used in traditional Chinese medicine.

OIt often grows at an altitude of 200-1800m hillside forest, thickets, meadows and Cunpang Tanabe, or in the natural distribution area of bone, widely cultivated. Most parts of China are distributed, located in North, South, East and Liaoning, Shaanxi, Gansu, Sichuan, Guizhou and Yunnan. Most of the country has produced. The main production Shandong, Anhui, Henan and other places.

Description:
Trichosanthes kirilowii is a flowering plant.A Climber,length up to 10m. Tubers cylindrical , fleshy , rich in starch. Stems thick, much branched , with longitudinal ribs and grooves are white stretch pubescent. Leaves alternate ; petiole length 3-10cm, with vertical stripes, is of pubescent ; tendrils 3-7 differences pubescent ; leaves low-quality , contour nearly round or nearly heart-shaped , length and width are about 5-20cm, often 3-5 ( -7 ) lobed to the crack, split or dilute parted and only ranging from large coarse teeth , diamond-shaped lobes obovate , oblong , apex obtuse, acute, often re- lobed edges , base heart-shaped , curved lack of deep 3-4cm, surface dark green , rough, back of the green, on both sides along the veins villous hairy hirsute , basal palmate veins 5 , veinlets reticulate. Dioecious ; male racemes solitary or with a single flower and students, or those in the upper branches solitary, too inflorescence total length 10-20cm, stout, with longitudinal ridges and grooves , puberulent , the top 5 -8 flower, single flower stalk about 15cm, pedicel about 3mm, small bracts obovate or broadly ovate, 1.5-2.5 (-3) cm, width 1-2cm, the upper coarsely toothed , base with handle , pubescent ; calyx tube cylindrical , long 2-4cm, apex expanded diameter of about 10mm, the lower diameter of about 5mm, pubescent , lobes lanceolate, length 10-15cm, width 3-5mm, entire; Corolla white , lobes obovate , about 20mm, width 18mm, with a central green tip apex sides fringed with filaments , pubescent ; anther connivent , about 2mm, diameter of about 4mm, filaments separated , stout, villous ; female flowers solitary, stalk length 7.5cm, pubescent ; calyx tube oblong, 2.5cm, diameter 1.2cm, with male and corolla lobes ; ovary oval, green , long- 2cm, style long 2cm, stigma 3. Fruit oval, flattened , long 11-16mm, width 7-12mm, light brown, almost at the edge of a ridge . Flowering from May to August , the fruit of August to October……CLICK & SEE THE PICTURES

Cultivation:
Requires a rich well-drained soil and plenty of moisture in the growing season. Sometimes cultivated in China for its edible fruit and medicinal uses. Male plants are favoured for root production. This species is not winter hardy in Britain and usually requires greenhouse cultivation. However, it may be possible to grow it as an annual in a very warm sheltered bed outdoors. A climbing plant, supporting itself by means of tendrils. Dioecious, male and female plants must be grown if seed is required.

Propagation:
Seed – sow March in pots in a warm greenhouse in a rich soil. Sow 2 – 3 seeds per pot and thin to the strongest plant. Grow them on fast and plant out after the last expected frosts. Give some protection, such as a frame or cloche, until the plants are growing away well.

Edible Uses:
Edible Parts: Fruit; Leaves; Oil; Oil; Root…….click & see

Fruit. The young fruits are pickled. The pulp of older fruits is eaten. Mature fruits are about 10cm long. Leaves and young shoots – cooked and used as a vegetable. An edible starch is obtained from the root. It requires leeching, which probably means that it has a bitter flavour. The root is harvested in the autumn, cut into thick slices, soaked for 4 – 5 days in water, changing the water daily until the root disintegrates and can be mashed into a fine pulp. It is then steamed into cakes or used for making dumplings. An edible oil is obtained from the seed.

Chemical components: The plant is a source of the toxic anti-HIV type I ribosome-inactiving lectin trichosanthin

Medicinal Uses:
Trichosanthes kirilowii is commonly used in Chinese herbalism, where it is considered to be one of the 50 fundamental herbs. Recent research has isolated a protein called “trichosanthin” in the roots and this is undergoing trials as a possible remedy for AIDS. Skin, vulnerary. The leaf and the stem are febrifuge. The fruit is antibacterial, anticholesterolemic, antifungal, depurative, emollient, expectorant and laxative. It is used in the treatment of pulmonary infections with yellow and thick sputum, chest pains, stuffy feelings in the chest, constipation and dry stool. It has an antibacterial action against E. coli, Bacillus dysenteriae, B. typhi, B. paratyphi, Pseudomonas, Vibrio cholerae, V. Proteus etc. The fruit is traditionally prepared as a winter soup to ward off colds and influenza. The fruit is harvested in the autumn and dried for later use. The rind of the fruit is used to treat a number of ailments, including cancer, jaundice, retained placenta, bronchial infections with thick phlegm and sore throat. The seed is antitussive, emollient and expectorant. The root is antibiotic, anti-inflammatory, febrifuge, galactogogue, laxative, oxytocic, sialagogue and uterine tonic. The fresh root has been noted for centuries as an abortifacient – a sponge soaked in its juice was placed in the vagina and induced an abortion in the second trimester of pregnancy. The root is taken internally in the treatment of diabetes, dry coughs, and to assist in the second stage of labour. The root is harvested in the autumn and dried for later use. The root and/or the seed is powdered and used in the treatment of mammary cancer.

Other Uses:
Oil; ……..An oil from the seed is used for lighting.
Known Hazards: Root extracts are extremely toxic. Intravenous administration can cause pulmonary oedema, cerebral oedema, cerebral haemorrhage and myocardial damage. Seizures and fever in HIV patients with parenteral administration. Self-medication of root not advised
Resources:
http://en.wikipedia.org/wiki/Trichosanthes_kirilowii
http://www.mdidea.com/products/new/new05602.html
http://www.naturalmedicinalherbs.net/herbs/t/trichosanthes-kirilowii=chinese-cucumber.php
http://www.pfaf.org/user/Plant.aspx?LatinName=Trichosanthes+kirilowii

Categories
Ailmemts & Remedies

Dehydration

Definition:
Water makes up around 75 per cent of the human body. It’s important for digestion, joint function, healthy skin and removal of waste products.
CLICK & SEE

Dehydration occurs when more fluid is lost from the body than is taken in. This causes an imbalance in important minerals, such as sodium and potassium, which are required for muscle and nerve function.

If there is a one per cent or greater loss in body weight because of fluid loss, dehydration occurs. This may be mild, moderate or severe, depending on the amount lost.

Infants and children are more susceptible to dehydration than adults because of their smaller body weights and higher turnover of water and electrolytes. The elderly and those with illnesses are also at higher risk.

Dehydration is classified as mild, moderate, or severe based on how much of the body’s fluid is lost or not replenished. When severe, dehydration is a life-threatening emergency.

Who are at Risk?
Anyone’s at risk of dehydration, but some people are more at risk than others.

•Babies and young children have relatively low body weights, making them more vulnerable to the effects of fluid loss.
•Older adults tend to eat less and may forget to eat and drink during the day. With increasing age, the body’s ability to conserve water decreases and a person’s sense of thirst becomes less acute. Illness and disability are also more common, which may make it harder to eat and drink enough.
•People with long-term medical conditions, such as kidney disease and alcoholism, are more at risk of dehydration.
•Short-term, acute health problems, such as viral infections, can result in dehydration because fever and increased sweating mean more fluid is lost from the body. Such illnesses may also make you feel less inclined to eat and drink.
•People living or working in hot climates or those who take part in sports or other strenuous physical activities are at greater risk of dehydration.

Symptoms:
The body’s initial responses to dehydration are thirst to increase water intake along with decreased urine output to try to conserve water. The urine will become concentrated and more yellow in color.

As the level of water loss increases, more symptoms can become apparent. The following are further signs and symptoms of dehydration:

•dry mouth,
•the eyes stop making tears,
•sweating may stop,
•muscle cramps,
•nausea and vomiting,
•heart palpitations, and
•lightheadedness (especially when standing).

The body tries to maintain cardiac output (the amount of blood that is pumped by the heart to the body); and if the amount of fluid in the intravascular space is decreased, the body tries to compensate for this decrease by increasing the heart rate and making blood vessels constrict to try to maintain blood pressure and blood flow to the vital organs of the body. This coping mechanism begins to fail as the level of dehydration increases.

With severe dehydration, confusion and weakness will occur as the brain and other body organs receive less blood. Finally, coma and organ failure, and death eventually will occur if the dehydration remains untreated.

Causes:
Around two-thirds of the water we need comes from drinks. Up to one-third comes from food (tomatoes, cucumber, fish and poultry are good sources). Some is also provided as a result of chemical reactions within the body.
CLICK & SEE

The average adult loses around 2.5 litres of water every day through the normal processes of breathing, sweating and waste removal. If we lose more fluid than usual this tips the balance towards dehydration.

Your body may lose too much fluids from:
•Vomiting or diarrhea
•Excessive urine output, such as with uncontrolled diabetes or diuretic use
•Excessive sweating (for example, from exercise)
•Fever

You might not drink enough fluids because of:
•Nausea
•Loss of appetite due to illness
•Sore throat or mouth sores

Dehydration in sick children is often a combination of both — refusing to eat or drink anything while also losing fluid from vomiting, diarrhea, or fever.

Lifestyle factors such as drinking too much alcohol, exercise, being in a hot environment or being too busy to drink liquid can also lead to dehydration.

Diagnosis:
Dehydration is often a clinical diagnosis. Aside from diagnosing the reason for dehydration, the health care practitioner’s examination of the patient will assess the level of dehydration. Initial evaluations may include:

•Mental status tests to evaluate whether the patient is awake, alert, and oriented. Infants and children may appear listless and have whiny cries and decreased muscle tone.

•Vital signs may include postural readings (blood pressure and pulse rate are taken lying down and standing). With dehydration, the pulse rate may increase and the blood pressure may drop because the intravascular space is depleted of fluid. People taking beta blocker medications for high blood pressure, heart disease, or other indications, occasionally lose the ability to increase their heart rate as a compensation mechanism since these medications block the adrenaline receptors in the body.

•Temperature may be measured to assess fever.

•Skin may be checked to see if sweat is present and to assess the degree of elasticity (turgor). As dehydration progresses, the skin loses its water content and becomes less elastic.

•Infants may have additional evaluations performed, including checking for a soft spot on the skull (sunken fontanelle), assessing the suck mechanism, muscle tone, or loss of sweat in the armpits and groin. All are signs of potential significant dehydration.

•Pediatric patients are often weighed during routine child visits, thus a body weight measurement may be helpful in assessing how much water has been lost with the acute illness.

Laboratory testing:-
The purpose of blood tests is to assess potential electrolyte abnormalities (especially sodium levels) associated with the dehydration. Tests may or may not be done on the patient depending upon the underlying cause of dehydration, the severity of illness, and the health care practitioner’s assessment of their needs.

Urinalysis may be done to determine urine concentration – the more concentrated the urine, the more dehydrated the patient.

Treatment:-
As is often the case in medicine, prevention is the important first step in the treatment of dehydration. (Please see the home treatment and prevention sections.)

Fluid replacement is the treatment for dehydration. This may be attempted by replacing fluid by mouth, but if this fails, intravenous fluid (IV) may be required. Should oral rehydration be attempted, frequent small amounts of clear fluids should be used.

Clear fluids include:
•water,
•clear broths,
•popsicles,
•Jell-O, and
•other replacement fluids that may contain electrolytes (Pedialyte, Gatorade, Powerade, etc.)
Decisions about the use of intravenous fluids depend upon the health care practitioner’s assessment of the extent of dehydration and the ability for the patient to recover from the underlying cause.

The success of the rehydration therapy can be monitored by urine output. When the body is dry, the kidneys try to hold on to as much fluid as possible, urine output is decreased, and the urine itself is concentrated. As treatment occurs, the kidneys sense the increased amount of fluid, and urine output increases.

Medications may be used to treat underlying illnesses and to control fever, vomiting, or diarrhea.

Home Treatment:
Dehydration occurs over time. If it can be recognized in its earliest stages, and if its cause can be addressed, home treatment may be beneficial and adequate.

Steps a person can take at home to prevent severe dehydration include:

•Individuals with vomiting and diarrhea can try to alter their diet and use medications to control symptoms to minimize water loss. Clear fluids often recommended as the diet of choice for the first 24 hours, with gradual progression to a BRAT diet (bananas, rice, apples, toast) and then adding more foods as tolerated.
•Loperamide (Imodium) may be considered to control diarrhea.
•Acetaminophen or ibuprofen may be used to control fever.
•Fluid replacements may be attempted by small, frequent amounts of clear fluids (see clear fluids information in previous section). The amount of fluid required to maintain hydration depends upon the individual’s weight. The average adult needs between 2 and 3 liters of fluid per day.
If the person becomes confused or lethargic; if there is persistent, uncontrolled fever, vomiting, or diarrhea; or if there are any other specific concerns, then medical care should be accessed.

Prevention:-
•Environment: Dehydration due to the weather is a preventable condition. If possible, activities should not be scheduled in the heat of the day. If they are, adequate fluids should be available, and cooler, shaded areas should be used if possible. Of course, people should be monitored to make certain they are safe. Those working in hot environments need to take care to rehydrate often.
•Exercise: People exercising in a hot environment need to drink adequate amounts of water.
•Age: The young and elderly are most at risk. During heat waves, attempts should be made to check on the elderly in their homes. During the Chicago heat wave of 1995, more than 600 people died in their homes from heat exposure.
•Heat related conditions: Know the signs and symptoms of heat cramps, heat rash, heat exhaustion, and heat stroke. Preventing dehydration is one step to avoid these conditions.

Carefully monitor someone who is ill, especially an infant, child, or older adult. If you believe that dehydration is developing, consult a doctor before the person becomes moderately or severely dehydrated. Begin fluid replacement as soon as vomiting and diarrhea start — DO NOT wait for signs of dehydration.

Always encourage the person to drink during an illness, and remember that a person’s fluid needs are greater when that person has fever, vomiting, or diarrhea. The easiest signs to monitor are urine output (there should be frequent wet diapers or trips to the bathroom), saliva in the mouth, and tears when crying.

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://www.bbc.co.uk/health/physical_health/conditions/dehydration1.shtml
http://www.medicinenet.com/dehydration/page4.htm
http://www.nlm.nih.gov/medlineplus/ency/article/000982.htm

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News on Health & Science

Freedom From the Daily JAB

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Indian scientists are using tissue engineering to give diabetes patients new insulin-making cells……...CLICK & SEE

Biomaterials scientist Prabha Nair is pitting her expertise of polymers to hold out a new line of hope for patients with diabetes who are dependent on insulin shots. In her laboratory, she has used two structures fashioned out of polymer materials to normalise blood sugar in rats with diabetes for up to 90 days. One of the polymer structures is designed to make insulin-secreting cells function properly, while the other is intended to protect such cells from threats that might emerge from the body’s immune system.

Nair and her colleagues at the government-funded Sree Chitra Tirunal Institute of Medical Sciences and Technology (SCTIMST), Thiruvananthapuram have combined two applications of polymers to tackle two major obstacles that have held back a promising but experimental treatment for diabetes from widespread use. The treatment, called islet cell transplantation, involves the removal of insulin-secreting cells from the pancreas of a deceased organ donor and their implantation into a patient with diabetes.

It is nearly a decade since researchers at the University of Alberta in Edmonton, Canada, demonstrated that islet cell transplantation may help patients with diabetes acquire normal blood sugar levels and achieve some level of freedom from the need for insulin.

A review of islet transplantation on 225 patients between 1999 and 2006 had revealed several benefits — including reduced need for insulin, improved blood glucose control, and lowered risk of hypoglycemia, according to the National Institute of Diabetes and Digestive and Kidney Disorders in the US. Two years after the islet transplantation, about one-third of the recipients were free of the need for insulin shots, the review suggested.

Islet cell transplantation, however, is not standard therapy yet. “There is a critical shortage of islet cells because of a shortage of organ donors,” says Nair, a scientist in the division of tissue engineering and regeneration technologies at the SCTIMST.

Patients who receive islet cells need to take immunosuppressive drugs throughout their lives to prevent their immune systems from destroying the implanted cells. These drugs have side effects including an increased risk of cancer.

The SCTIMST researchers harvested a class of cells known as pancreatic progenitor cells from mice and placed them in a cocktail of appropriate biochemicals where they turn into insulin-secreting islet-like cells.

The scientists then loaded these islet-like cells into three-dimensional scaffolds constructed out of a gelatin, a natural polymer, and polyvinylpyrrolidone, a synthetic polymer. The islet-like cells proliferate on the scaffolds and serve as a potential source of insulin.

In experiments, the scientists observed that rats with diabetes that received these islet cell-bearing scaffolds alone died within 20 days. Their scaffold cells had been attacked by the rats’ immune systems, leading to the destruction of tissue and the failure of the implantation.

“We also designed a polymer capsule to shield the implanted islet cells from the immune system,” Nair told KnowHow. When the scientists combined the scaffolding, also called tissue engineering, with encapsulation, the rats survived for up to 90 days.

The rats were models for type-I, or insulin-dependent diabetes, but researchers say the tissue engineering and encapsulation strategy may also be considered as a possible option for patients with adult-onset diabetes who need insulin injections. Given the differences in the lifespans of rats and humans, some researchers believe the 90-day freedom from insulin observed in the laboratory animals may be equivalent to several years in humans — although exactly how long is still a subject of debate.

“These results are really exciting,” says Aroop Dutta, a tissue engineering specialist and founder of ExCel Matrix Biologicals, a Hyderabad-based start-up in biomaterials and tissue engineering, who was not connected with the research in Thiruvananthapuram.

“There just aren’t enough human-derived islet cells for the large numbers of diabetes patients dependent on insulin. Animal cells or stem cell-based approaches are the only viable options as sustained sources of islet cells,” he adds.

The results of the SCTIMST’s experiments were published last Friday in the journal Acta Biomaterialia. The researchers say their use of islet cells from mice in rats with diabetes suggests that the polymer capsule that keeps the immune system at bay may facilitate xenotransplants — the use of cells or organs across species — as an option for reversing diabetes. “But there is still much work to be done,” Nair cautions.

“We’ll need to establish that this also works in large animals,” she said. The SCTIMST group plans to initiate studies in pigs with diabetes. If the technique is indeed shown to work in large animals too, it could be ready for human clinical trials within two or three years.

Source : The Telegraph ( kolkata, India)

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