Sunday, July 26, 2009

Improved RNA interference kits launched by Imgenex

RNA interference (RNAi) is the process of mRNA degradation that is induced by double-stranded RNA in a sequence-specific manner. RNAi has been observed in all eukaryotes, from yeast to mammals. The RNAi pathway is thought to be an ancient mechanism for protecting the host and its genome against viruses and rogue genetic elements that use double-stranded RNA (dsRNA) in their life cycles. They have also been shown to play a role not only in mRNA and dsRNA stability/degradation, but also in regulation of translation, transcription, chromatin structure, and genome integrity. In plants and animals, RNA silencing has been adapted to play a critical role in regulation of cell growth and differentiation using a class of small RNAs. In the RNA interference process, the dsRNAs get processed into 20-25 nucleotide (nt) small RNAs by an RNase III-like enzyme called Dicer. Then, the small RNAs assemble into endoribonuclease-containing complexes known as RNA-induced silencing complexes (RISCs), unwinding in the process. The small RNA strands subsequently guide the RISCs to complementary RNA molecules, where they cleave and destroy the cognate RNA (effecter step). Cleavage of cognate RNA takes place near the middle of the region bound by the siRNA strand. The small RNAs that provide target specificity to the silencing machinery includes short interfering RNAs (siRNAs), repeat-associated siRNAs (rasiRNAs), and microRNAs (miRNAs) and is distinguished by their origin. siRNAs are processed from dsRNA precursors made up of two distinct strands of perfectly base-paired RNA, while miRNAs originate from a single, long transcript that forms imperfectly base-paired hairpin structures. siRNAs were originally identified as intermediates in the RNAi pathway after induction by exogenous dsRNA; however, endogenous sources of siRNAs have now been recognized. The endogenous siRNAs are derived from repetitive sequences within the genome, and are termed repeat-associated siRNAs, or rasiRNAs. miRNAs were discovered through their critical roles in development and cellular regulation, and represent a large class of evolutionarily conserved RNAs. miRNAs have always been recognized as being of endogenous origin. RNA interference has emerged as a natural mechanism for silencing gene expression over the past decade. This ancient cellular antiviral response can be harnessed to allow specific inhibition of the function of any chosen target genes, including those involved in causing diseases such as cancer, AIDS, and hepatitis. It is already proving to be an invaluable research tool, allowing much more rapid characterization of the function of known genes. More importantly, the technology considerably bolsters functional genomics to aid in the identification of novel genes involved in disease processes. Last but not the least the technology can be harnessed as a novel therapeutic agent and is suitable for combating viral diseases, cancers and inflammatory diseases.
Imgenex (San Diego) recently launched the pSuppressorAdeno construction kit for adenovirus mediated gene knockdown. The kit provides the ability to infect a broad range of cell types, including many primary cell lines as well as dividing and nondividing cells, according to a company official. The kit also offers the flexibility to validate sequences using the nonviral expression plasmid prior to construction of adenoviruses, notes Sujay K. Singh, Ph.D., president and CEO of Imgenex, which markets plasmid-based RNA interference (RNAi) products. “One of the greatest advantages is the ability of recombinant adenovirus vectors to reduce gene expression both in vitro and in vivo,” he adds. RNAi, initially considered a bizarre attribute of petunias and later a gene-silencing mechanism in worms, is creating a stir as one of the hottest new technologies in molecular biology. It is revolutionizing the field of functional genomics.
Author Resource:- IMGENEX India Pvt Ltd. the only biotech company in Orissa and one of its kinds in Eastern India. IMGENEX India started in Oct as an outsourcing branch of IMGENEX Corporation, San Diego, USA. Find out more information about RNA interference.

Friday, July 24, 2009

Pollen allergy may be the reason for your sneezing in spite of a change in seasons

About Hay Fever

In the various seasons (spring, summer, and fall) during the year, pollen grains are dispersed from trees, weeds, and grasses. These pollen grains travel on air currents to fertilize other plants. Inhaling pollen, in some people, can trigger seasonal allergic rhinitis which is also called pollen allergy or hay fever. In this condition the mucous membranes in the nasal passages inflame, which causes swelling, sneezing, itching, irritation and a runny nose.

Allergy seasons are:

• May - July/August – Grass pollen:
• Feb – June – Tree pollen (depending on whether allergic to early or late flowering trees)
• August – September – Nettle/weed pollen

Hay fever symptoms can continue all the year round and may also occur from indoor allergens like house dust mites, pets and possibly indoor moulds.

Hay fever is actually an attempt by the body to rid itself of allergens but the immune system overreacts and releases chemicals which cause inflammation, causing:

• Itchy, watery, red eyes
• Frequent sneezing
• Constantly dripping nose

Sufferers, when afflicted with this condition, have to struggle to breathe through their nose. Symptoms are often quite bad in young people and tails off in later years as the body adapts. Studies have shown that hay fever can severely affect the quality of life, disturb sleep patterns, impair daytime concentration and work performance.

What is pollen allergy?

Pollen once released from trees, weeds and grasses, ride on air currents with a mission to disperse and fertilize other plants. However, they rarely reach their targets. On the way they get into human noses and throats, triggering allergic reactions.

Pollen is one of the most pervasive things that can cause an allergy and cannot be avoided. Many allergy causing foods, drugs, or animals can be largely avoided but insects and household dust are inescapable. However, short of staying indoors, there is no foolproof method of evading windborne pollen. Nonetheless, ways have been established that help ease the symptoms of hay fever. Moreover, scientists are working to find better approaches to allergy treatment.

Research has helped provide a better understanding of the causes of allergy, improve the methods for diagnosing and treating allergic reactions and thereby eventually preventing them. The common signs and symptoms of pollen allergy are:

• Sneezing, the most common, may be accompanied by a runny or clogged nose
• Itching eyes, nose, and throat
• Allergic shiners (dark circles under the eyes caused by restricted blood flow near the sinuses)
• The "allergic salute" (in a child, persistent upward rubbing of the nose that causes a crease mark on the nose)
• Watering eyes
• Conjunctivitis (is inflammation of the membrane that lines the eyelids, causing red-rimmed eyes)

In a pollen-sensitive person, as soon as the allergy-causing pollen lands on the mucous membranes of the nose, a chain reaction occurs that leads the mast cells in these tissues to release histamine. This potent chemical dilates the small blood vessels in the nose; causing the fluids to escape through the expanded vessel walls, which in turn results in swelling of the nasal passages as well as nasal congestion. On the other hand, histamine also causes itching, irritation, and excess mucus production. Similarly, other chemicals like prostaglandins and leukotrienes also contribute to allergic symptoms.

Some people with pollen allergy also develop asthma, a serious respiratory condition, which can eventually become chronic. Symptoms include coughing, wheezing and shortness of breath due to a narrowing of the bronchial passages and excess mucus production.
Author Resource:- Webmaster associated with hay fever related site. This site provides various information headache and pollen allergy.Resources are available on site headclinic.co.uk

Wednesday, July 8, 2009

Herbs to Lower Cholesterol, Cholesterol Lowering Herbs

High cholesterol can be found in any person. Still, at more risk are people who lead stressful lives but also maintain unhealthy diets. In order to lower your cholesterol level, the best thing to do is eat foods that are low in fat content (especially one kind of fat – saturated fat) but also to increase the amount of physical activity. Cholesterol lowering herbs are generally available for people who do not start taking prescription drugs to lower cholesterol immediately. This article will also give you some examples of herbs that lower cholesterol.

Cholesterol is responsible for causing fatty deposits to harden and accumulate in the arteries. These fatty deposits harden to form a substance called plaque, which blocks the artery and prevents blood from flowing and reaching organs such as the brain. Blocked arteries are responsible for strokes and heart disease.

Herbs that lower your blood cholesterol levels are actually a fairly new science. In today’s society, increased LDL cholesterol has become a major health issue. New ways to lower cholesterol naturally are researched by people of all over the world due to this. Because of the lack of side effects and contraindications, natural supplements to lower cholesterol levels are often preferred to their drug counterparts.

Other herb products that lower cholesterol include plant stanols and sterols. these are naturally occurring substances found in some plants. Stanols can also be found in dietary supplements or are added to margarine, orange juice as well as in dressings. According to research findings, plant stanols help reduce cholesterol, and being similar in structure to cholesterol, help in blocking absorption of cholesterol from the intestines.

Since ages guggul has been the companion of mankind saving him from many diseases. Botanically known as Commiphora mukul, it is a wonderful herb that is responsible for treating so many ailments that man suffers. The powerful action of guggulu helps in lowering down the levels of triglycerides and cholesterols there by managing the proper ratio of High density lipoproteins to low density lipoproteins. In a study it was proved that guggulu helps in lowering the cholesterol levels by 15 to 28 % and triglycerides level by 20 to 30 %.

Garlic. Garlic is a cholesterol lowering herb that is slowly but heavily gaining popularity. It has been shown through medical reports that it can increase the HDL cholesterol levels while lowering LDL levels. Studies have also shown that garlic can reduce both triglycerides and cholesterol by up to 15 percent. In one study, people who were given 800 milligrams (about one clove) of garlic daily experienced lower cholesterol levels as well as lower blood pressure.

Artichoke leaf is another herb that helps lower cholesterol levels. This herb works by limiting the synthesis of cholesterol in the body. Artichokes are also known to contain cynarin that supposedly increases bile production in the liver and speeds the flow of bile from the gallbladder, which together increases the excretion of cholesterol Author Resource:- Read about guggul, lower cholesterol naturally and treatment for obesity

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