Medical Publishing

Archive for January, 2010

3. Replication

The virus, lacking the enzymes and metabolic precursors necessary for its own replication, they must obtain them from the host cell they infect. Viral replication is a process that includes several separate synthesis and subsequent assembly of all components to give rise to new infectious particles. Replication is initiated when the virus enters the cell: cellular enzymes remove the cover and the DNA or RNA is contacted with the ribosome, directing the synthesis of proteins. The virus nucleic acid autoduplicates and, once synthesized protein subunits that form the capsid, the resulting components are assembled into new viruses. A single virus particle can cause a progeny of thousands. Some viruses are released by destroying the infected cell, and yet leave the cell without destroying it by a process of exocytosis that leverages own cell membranes. In some cases the infection is ‘silent’, ie the viruses replicate inside the cell without evident harm.

RNA-containing viruses are unique replicative systems, since the RNA autoduplicates without the involvement of DNA. In some cases, viral RNA functions as messenger RNA, and replicates indirectly using the ribosomal system and the metabolic precursors of the host cell. In others, the virus carried in the cover-dependent RNA enzyme that directs the synthesis process. Other RNA viruses, retroviruses, may produce an enzyme that synthesizes DNA from RNA. Formed DNA then acts as the viral genetic material. Read the rest of this entry »

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1. Introduction

(Latin for ‘poison’) organizational entities composed only of genetic material surrounded by a protective envelope. The term virus was used in the last decade of last century to describe the disease-causing agents smaller than bacteria. Lack of independent living but can replicate inside living cells, often damaging to his guest in this process. The hundreds of known viruses are the cause of many different diseases in humans, animals, bacteria and plants.

The existence of viruses was established in 1892, when Russian scientist Dmitry I. Ivanovsky, found microscopic particles, known later as the snuff mosaic virus. In 1898 the Dutchman botanist Martinus W. Beijerinck called these particles infectious virus. A few years later, viruses were found growing on bacteria, which are called bacteriophages. In 1935, the American biochemist Wendell Meredith Stanley crystallized the snuff mosaic virus, showing that consisted only of genetic material called ribonucleic acid (RNA) and an envelope protein. In the 1940s the development of electron microscopy enabled the visualization of the virus for the first time. Years later, the development of high-speed centrifuges able to concentrate and purify. The study of animal virus reached its peak in the 1950s with the development of cell culture methods, support of viral replication in the laboratory. Then they discovered many viruses, most of which were sampled in the 1960s and 1970s, in order to determine their physical and chemical characteristics. Read the rest of this entry »

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• Wash hands after using the toilet and before eating.

• Avoid eating in the street and in places of dubious hygiene.

• Boiling water or drink bottled water.

• Maximize hygiene measures in handling the faeces, especially in young children, older adults and people who require care.

• worming twice a year. All family members should undergo deworming to prevent possible reinfection.

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One of the most common forms of transmission is through ingestion of eggs or cysts that are found in the faeces excreted by infected individuals.

Food can be contaminated with these wastes, when irrigated with sewage and lack of hygiene during preparation and intake process. As can generalize that the transmission mechanism for these diseases is that of the three passes, “the year goes hand in hand to mouth and mouth passes into the intestine.

Organisms that can live as parasites in our intestines are very varied. The most common are: worms may clog the intestines and invade the respiratory tract and bile giardia, which adhere to the bowel wall and mechanical irritation caused by diarrhea and malabsorption of food, amoeba, which by producing toxins destroy the tissues of the gut and migrate to other organs like the liver, hookworms, which adhere to the intestinal wall and feed on blood, and finally, the cysticerci that pierce the intestinal mucous layer, reaching the vessel blood and spread to the muscles, brain, eye, liver, among others.

Many of those infected by parasites have no complaints. Even in some cases the symptoms are so mild that near-misses, but this does not mean it is not parasites and can spread to others.

Exist to reach the symptoms that occur most frequently are:
• Diarrhea or constipation.
• Stomach pain (colic or cramps).
• Inflammation of the stomach.
• Headache.
• Gases.
• Nausea.
• Belching.
• Vomiting.
• Itching in the anus.
• Intolerance to certain foods.
• General weakness.
• Loss of appetite.
• In small, worms and parasites can cause slow growth and poor weight gain.
• Lack of attention at work, depression and fatigue.

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Water is the major component of our body and is essential for life, therefore we could not live without it. For our body to function properly we need about three liters of water a day.

1. What is it?
Water is a colorless, odorless, tasteless and is the drink par excellence. It is an essential component of nature but also is the main component of our body, where it performs important functions. Water is essential for life.

2. The proportion of water in our bodies
Proportions. The proportion of water varies according to sex. It is the main component of our body, representing two thirds of the weight of it.

Taking as an example a 70 kg, water represent approximately 43 liters, representing about 61% of the total weight, while two-thirds within the cells and the extracellular rest.

This proportion of water in our body varies by age and sex. Thus, women, having more fat and less muscle mass, has a somewhat lower water content, which ranges between 50-55% of its total weight. In the newborn this percentage is 80%, which decreases with age, reaching a value of 50% in the elderly.

The water content of our body is kept constant thanks to the balance between the quantity of water consumed daily and the daily loss of it.

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The wall lining of the gastrointestinal tract is constantly in contact with microorganisms or ingested food. About five hundred species of bacteria live in the adult gastrointestinal tract, mainly in the large intestine.

This community of microbes not only live in peaceful coexistence with humans, but also plays an important role in the welfare of the individual. There is a constant and complex interaction between these bacteria, cells in the intestine and immune system.

Probiotics are defined as live microorganisms which, when administered in adequate amounts, confer a beneficial effect on health of people.

The most frequently used probiotics are bacteria of the genus Lactobacillus and Bifidobacterium that are part of normal healthy bowel. Other probiotics include yeasts.

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Different types of treatment available for patients with chronic lymphocytic leukemia. Some treatments are standard (the currently used treatment) and some are being tested in clinical trials. Before starting treatment, patients should consider participating in a clinical trial.

A treatment clinical trial is a research study designed to improve current treatments or obtain information on new treatments for cancer patients. When clinical trials show that a new treatment is better than treatment “standard”, the new treatment may become standard.

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