Many countries have strict rules regarding HIV positive and symptomatic AIDS patients and do not allow entry to their countries, although there is no data which suggests that these restrictions can/have reduced HIV transmission. In general HIV testing is required who wish to study/work abroad or wish to stay for more than 3 months. Some countries do not accept any HIV testing done in the traveler’s home country and border/airport officials have power to send back the traveler if they find any anti-retroviral medication (such as zidovudin) with the traveler. Some countries accept HIV testing report of less than 6 months old. If you are traveling to a particular country, you should get the latest information (because the rules may be changed frequently) on HIV testing requirement from the particular country’s embassy.

Consumption of alcohol by humans dates back to thousands of years in history. It is difficult to know the exact date when alcohol was invented and its consumption started. In the mythological stories of different countries, there are mentions about alcohol. Alcohol has become part of cultures in many communities. Alcohol is taken to celebrate and alcohol is also taken in sorrow and probably no other substance has this unique distinction.

Mechanism of intoxication of ethyl alcohol:

Different experts on the subject may explain the mechanism of intoxication caused by ethyl alcohol in different ways. I believe the main cause of intoxication after alcohol consumption, is the way alcohol is metabolized in our body. The effect of alcohol in the central nervous system (CNS) is stimulatory as well as depressive.

The most important consequence of obesity is increased risk of death. Obesity is one of the leading causes of health problems. Obesity is responsible for higher morbidity and mortality. The risk of death from all causes is approximately 100% higher in compared to a normal weight individual. Obesity and overweight (BMI of 25-30) is leading cause of preventable death throughout the world, including in underdeveloped and poor countries. Obesity is responsible for more than 300,000 deaths annually in United States alone. The life expectancy of moderately obese individual is 2-5 years less than normal individuals and much lesser in highly obese individuals.

The important consequences (complications) of obesity include development of insulin resistance and type-2 diabetes, different cardiovascular diseases, respiratory diseases, increased incidence of gall stones, increased incidence of cancer, reproductive disorders, diseases of bones and joints etc.

Obesity is caused by complex interaction of genetic and environmental factors. It is difficult to determine if genetics play a dominant role or environmental factors play the dominant role in causation of obesity. In general a favorable environment and a genetic susceptibility interact to cause obesity.

The actual causes of obesity are still not clear despite tremendous development in medical science, including understanding of molecular pathways which regulate energy balance in humans, an essential component in pathogenesis of obesity. The cause obesity seems to be simple, such as chronic and excess consumption of food (calories) than expenditure of energy. But this theory of chronic excess nutrient intake relative to the level of energy expenditure does not hold in every obese individual, which proves that there are several other causes of obesity than simple consumption of excess food than we need.

Genes vs. Environment in Obesity:

During the time of evolution of humans, the food supply was intermittent and for survival there was need to store energy in excess of what is required for immediate use. Fat cells did the job of storing energy, which are widely distributed in adipose tissues. The fat cells can store excess energy efficiently as triglyceride and, when needed, release stored energy as free fatty acids for use at other sites. This physiologic system developed during the time of evolution acts through endocrine and neural pathways and even can permit humans to survive starvation for as long as several months. But at present era of nutritional abundance, sedentary lifestyle, and influenced importantly by genetic endowment, this physiologic system of storing energy in adipose tissues can produce obesity and adverse health consequences due to obesity.

Blood and blood products are collected as whole blood from donors in various anticoagulants. The blood and blood products which are used for transfusion are whole blood, packed red blood cells (PRBCs), platelet concentrates, fresh frozen plasma (FFP), cryoprecipitate, and plasma derivatives. Plasma derivatives are also used for transfusion such as albumin, intravenous immunoglobulin, anti-thrombin, and coagulation factor concentrates. Plasma derivatives are generally collected from several donors and pooled together and infectious organisms are removed by treating.

Separation of blood components from whole blood:

Blood is collected as whole blood of 450 ml (one unit of blood) in various anticoagulants. The whole blood is then processed to produce blood various blood components mentioned above. Most commonly blood is transfused as whole blood. To get blood components, whole blood is first separated by slow centrifugation into PRBCs and platelet rich/concentrated plasma.