Each Viral Infection Has Its Specific Symptoms

Some time ago one of most terrible diseases was considered natural smallpox, virus of which may live only in human body. During two decades in the world there were registered no cases of infecting human with natural smallpox, it means that the virus causing the disease ceased to exist in wild life. This occurred due to compulsory vaccination against smallpox in past.

Before 1958 each year in the world the diagnosis “smallpox” was made at average 250,000 times. In 1958 the WHO started the campaign of total smallpox liquidation. In 1980 was declared that the Earth is free of natural smallpox.

Each cell in the body performs a number of specific individual functions. After infecting with virus sooner or later do appear problems. Virus damages liver cells – this causes yellow disease and other signs of liver failure. Virus damages mucosa of bronchi – this causes cough, rhonchi in lungs and hurried breathing.

Virus enters cells of the brain – do appear disorder of consciousness, cramps, paralysis. Selectivity of viruses leads to the fact that each viral infection has its specific symptoms and the symptoms will be determined by inability of group of cells damaged by viruses to perform their functions.

Severity of viral infection depends on what cells and how many of them are damaged. It is clear that damage of brain leads to more serious illness than damage of cells of nasal mucosa.

Every cell in human body changes in a certain way during its growth and development. It means that liver cell of a child is not the same as liver cell of an adult. In a child hepatic cell is not maturated yet and hepatitis A virus can hardly multiply in these immature cells, therefore one-year-child never gets diseased with hepatitis A, in older children the disease courses mildly, in teenagers severely than in children, in adults it courses severe.

Childhood infection (rubeola, chickenpox) do course severe in adults. The severity of disease is determined by the condition of a particular cell. For example, hepatic cell of a drunker is weaker than in a non-drunker.

The Variety Of Viruses

 Virus may be seen only with the help of electronic microscope. The vast majority of doctors meet viruses and electronic microscopes only on images in clever medical books. Diseases caused by viruses  have so specific symptoms that it makes no use of  electronic microscope and images because everything is clear.

The essential and most significant biological peculiarity of any virus is that it is unable to multiply without cells of other organisms. Virus enters a particular cell and this infected cell transforms into a factory of virus production.

It is clear that cell cannot work for both virus and body and thus it cannot perform its major function and here appear absolutely specific symptoms of the disease. Major feature of the virus is its selectivity. Virus cannot live in any cell, it needs a proper one which will work for it.

For example, infectious hepatitis virus may live and multiply only in liver cells. Epidemic parotitis virus (mumps) prefers cells of salivary gland, influenza virus – cells of mucous membrane of bronchi and tracheae, encephalitis virus – cells of cerebrum. Each virus may be associated with particular cells and tissues of human body which virus damages.

Virus selectivity is observed not only in damages of particular cells but also in the ability to cause particular diseases in particular biologic species. Measles virus may find necessary cells in human body and is not dangerous for a cat. Virus of hardpad is not dangerous for a human.

These are not common rules. Particular cells of different mammals are analogous with each other and some viruses cause one and the same disease in different animals, for example, rabies virus. The ability of some viruses to affect only particular biological species has a great significance.

Remedy Against Melanoma Found In Immunity

American scientists have developed a new method to treat melanoma which was successfully tested on mice.

What melanoma is
Melanoma is a cancerous growth on the skin that is developed from pigment cells containing melanin. Externally melanoma resembles a usual mole, however, there exist particular signs that help to define  cancerous growth. Unlike mole, cancerous growth is a non-symmetric formation with irregular edges and its diameter is more than 5mm. In some cases inoffensive mole which did not show itself for years  may turn into melanoma.

Signs that mole turns into melanoma:

• size increase
• color change
• reshaping
• itching
• ulceration
• bleeding

Major factor leading to melanoma development is action of ultraviolet irradiation.

What are the dangers of melanoma?
Major danger of melanoma is that even small tumors give metastasis into all organs and tissues of the body. The process of metastasis formation presents spreading of cancerous cells via lymphatic and blood vessels. When cancerous cells get into healthy organs and tissues they start multiplying which significantly aggravates treatment and the prognosis for treatment.

History of the research
Watching the mice which had no genes responding for production of special type of immune cells – T helper 17 cells., scientists found that in those mice melanoma was not developed. Thus appeared a hypothesis that blocking of signal path of T helper 17 cells would help to stop tumor growth. Besides this, scientists found that in mice bodies was presented a specific substance called interleukine that is formed under the action of other immune cells – T helper 9 cells.

Essence of the research
The research was performed on mice in which scientists modeled melanoma. As a treatment, scientists injected T helper 9 cells in mice. It turned out that immune therapy helps to slow down tumor growth. Besides this, scientists discovered that in a healthy man T helper 9 cells are found in blood and skin while in melanoma this type of immune system cells is absent or is found in small amounts.

Results of the research
Today is actively developed a new method of cancer treatment called immune therapy. Results of the latest study tell about success of usage drugs stimulating immune system in patients with melanoma. Scientists hope that data obtained will help to perform new studies to evaluate the role of T helper 9 cells in cancer treatment.

Bird Flu Just Three Mutations Away

Bird flu virus continues to mutate. If it would be able to transmit from human to human than humanity would face a new pandemic.

In spite of the fact that bird flu is the disease of birds, some viruses of bird flu may infect humans and cause severe infections that often end up with death.

Today bird flu virus is not transmitted from human to human. However, if the virus mutates, it may begin to transmit from human to human which may result in a pandemic.

Scientists claim that only several mutations do separate humans from a real pandemic.

Lack of Sleep and the Immune System

A group of researchers from Great Britain and Netherlands studied how human body reacts on lack of sleep. Like stress, lack of sleep (including chronic one) has negative effects on the immune system. 

During stress human body starts to produce granulocytic cells, a kind of leukocytes. Lack of sleep has the same effects. It was proved by a study in which participated 15 young people who slept 8 hours  daily during a week, after which they did not sleep for 29 hours.

Tests have shown that 29 hours of insomnia provoked not only increase in production of granulocytic cells but also break in rhythm of renewal of white blood cells. It was proved that lack of sleep may cause different diseases such as obesity, diabetes and increased blood pressure.

Researchers also say that chronic lack of sleep leads to absorption of body immune system. In the very near future they intend to make one more study during which they plan to study body reaction on stress at molecular level in order to understand how exactly lack of sleep provokes different diseases.

Scientists consider that results of the study are an occasion to overview schedule of work in professions which are connected with long periods of awakenings, for example, where people work in rotating teams.

How To Fight Summer Cold

It is considered that colds are winter problems. In fact, 20% cold-related diseases occur in summer months. To catch a cold in heat is not just an annoying confusion. Specialists say summer colds are more dangerous than winter ones because summer symptoms are not so manifestative. Many people do not pay attention to sore throat and running nose and therefore even do not try to treat them. So they feel sick for a longer time.

There exists another cause. Upper respiratory tract infections together with sore throat, cough, running nose, temperature increase are caused by parainfluenza viruses, coronaviruses and rhinoviruses. They circulate all the year round but in summer time enterovirus joins them and it shows with rash on skin and diarrhea. Enterovirus is transmitted not only via dirty hands but also via airborne. It means that risks to catch a virus in summer time even increases.

Why do we catch cold in summer?
1. Air-conditioner
Habitually we do escape from heat and prefer to stay in places with air-conditioners and ventilators, but namely they are major causes of colds. Permanently circulating air dries nasal mucosa that is a protective barrier against infections which makes viruses easily enter the body. Besides this, conditioned air is not only dry but also cold one and these are perfect conditions for virus replication.

Solution: do not do at home air colder than 21C. Ideally, the difference between air temperature in the house or office and outside must be not more than 5 – 7C.

2. Icy drinks
Sensation that icy drinks allay thirst is deceptive one. They do freshen up for a quite short time but for throat it is a real icy shock. Overchilled mucous loses its ability to fight viruses and bacteria. After ice cream and other diary products those effects are stronger than after icy juice or water.

Solution: do not drink beverages with ice. It would be better to eat slightly melted ice cream. It is necessary to drink beverages or eat cold food with small portions in order to let them warm in the month.

3. Journeys
In summer we do actively travel and microorganisms do travel with us. In hotels holidayer may face infections unknown before. There is a major risk to catch a virus in air plane. Restricted space of air plane together with very dry air is an ideal medium for disease transmission. It was proved that chance to catch a cold depends directly on duration of flight – the longer you fly, the higher the risks are.

Solution: do not admit mucous drying, use rewetting drops and sprays for nose, drink more water. In vacations use antibacterial wet wipes. Remember that easiest way to catch cold is after flight during period of acclimatization. Those who like to spend time under the sun should know that the excess of solar radiation lowers the immunity.

Low Dose of Stress Strengthens Immunity

It is well known fact that chronic stress is destructive for the body, however, low doses of stress may be helpful. According to a research, acute stress has positive effects on human nature, makes him more accurate and punctual, and sets up his immune system.

During experiments scientists subjected participants to small stress by making them solve simple and difficult tasks, and then invited them to play a game connected with the ability to share. It turned out that those who experienced more stress, were more friendly, generous and trustworthy.

Acute stress helps to better memorizing, say scientists from Buffalo University, USA. Experiments were performed on rats and they showed that stressed animals digest information more quickly and do reproduce it more exactly. The point is that stress hormone cortisone has protective effects on prefrontal parts of brain cortex which controls emotions and learning.

Low dose of stress strengthens the immune system. Review of 300 scientific works showed that chronic stress weakens defense mechanisms of the body making it more vulnerable to infections. Short-term stress trains the immunity, making it more willing to fight pathogens.