Cancer (medicine), any of more than 100 diseases characterized by excessive, uncontrolled growth of abnormal cells, which invade and destroy other tissues. Cancer develops in almost any organ or tissue of the body, but certain types of cancer are more life-threatening than others. In the United States and Canada cancer ranks as the second leading cause of death, exceeded only by heart disease. Each year, about 1.7 million Americans and more than 150,000 Canadians are diagnosed with cancer, and more than half a million Americans and about 70,000 Canadians die of the disease.
For reasons not well understood, cancer rates vary by gender, race, and geographic region. For instance, more men than women develop cancer, and African Americans are more likely to develop cancer than people of any other racial group in North America. The frequency of certain cancers also varies globally. For example, breast cancer is more common in wealthy countries, and cervical cancer is more common in poor countries.
Although people of all ages develop cancer, most types of cancer are more common in people over the age of 50. Cancer usually develops gradually over many years, the result of a complex mix of environmental, nutritional, behavioral, and hereditary factors. Scientists do not completely understand the causes of cancer, but they know that certain lifestyle choices can reduce the risk of developing many types of cancer. Not smoking, eating a healthy diet, and exercising moderately for at least 30 minutes each day can lower the likelihood of developing cancer.
Just 60 years ago a cancer diagnosis carried little hope for survival because doctors understood little about the disease and how to control it. Today about two-thirds of all Americans diagnosed with cancer live longer than five years. While it is difficult to claim that a cancer patient is disease free, long-term survival significantly improves if the patient has had no recurrence of the cancer for five years after the initial diagnosis. For years, death rates from cancer were rising in developing countries.
In 2006 the American Cancer Society reported that the number of cancer deaths in the United States dropped for two years in a row. The decrease was attributed to a decline in smoking, earlier detection, and improved treatment.
The National Cancer Institute of the United States (NCI) estimates that more than 10 million Americans are living with cancer or have been cured of the disease thanks largely to advances in detecting cancers earlier. The sooner cancer is found and treated, the better a person’s chance for survival. In addition, advances in the fundamental understanding of how cancer develops have reduced deaths caused by certain cancers and hold promise for new and better treatments.
How cancer Develop.
Cancer begins in genes, bits of biochemical instructions composed of individual segments of the long, coiled molecule deoxyribonucleic acid (DNA). Genes contain the instructions to make proteins, molecular laborers that serve as building blocks of cells, control chemical reactions, or transport materials to and from cells. The proteins produced in a human cell determine the function of each cell, and ultimately, the function of the entire body.
In a cancerous cell, permanent gene alterations, or mutations, cause the cell to malfunction. For a cell to become cancerous, usually three to seven different mutations must occur in a single cell. These genetic mutations may take many years to accumulate, but the convergence of mutations enables the cell to become cancerous.
Causes of cancer.
Scientists do not fully understand the causes of cancer, but studies show that some people are more likely to develop the disease than others. Scientists called epidemiologists study particular populations to identify why cancer rates vary (see Epidemiology). One method they use is to compare cancer patients with healthy people in terms of behavior such as diet, exercise, and smoking and traits such as gender, age, and race. Population studies provide useful information about risk factors that increase the likelihood of developing cancer.
A. Carcinogens.
One of the greatest risk factors for cancer is prolonged or repeated exposure to carcinogens—chemical, biological, or physical agents that cause the cellular damage that leads to cancer. The details of how carcinogens cause cancer remain unclear. One theory is that exposure to carcinogens, when combined with the effects of aging, causes an increase in chemicals in the body called free radicals. An excessive number of free radicals causes damage by taking negatively charged particles called electrons from key cellular components of the body, such as DNA. This may make genes more vulnerable to the mutating effects of carcinogens.
B. Smoking
Smoking causes up to 30 percent of cancer deaths in the United States and Canada, making tobacco smoke the most lethal carcinogen in North America. Smoking is associated with cancer in the lungs, esophagus, respiratory tract, bladder, pancreas, and probably cancers of the stomach, liver, and kidneys. The risk of cancer increases depending on the number of cigarettes smoked per day, the cigarette’s tar content, and how many years a person smokes. Starting to smoke while young significantly increases the risk of developing cancer.
Each year in the United States, several thousand nonsmoking adults die of lung cancer caused by exposure to the smoke of others’ cigarettes, called secondhand smoke or environmental tobacco smoke. Nonsmoking spouses of smokers are 30 percent more likely to develop lung cancer than those married to nonsmokers. Breathing secondhand smoke also increases the risk of cancer in the children of smokers and in nonsmokers who work in smoky places. For this reason smoking has been banned in many places such as restaurants and bars.
Cigars, pipes, and smokeless tobacco have also been implicated in increased risk for cancer. Cigars contain most of the same cancer-producing chemicals as cigarettes, and people who smoke cigars have a 30 percent higher risk of developing cancer than nonsmokers. Oral cancers occur more frequently in people who use smokeless tobacco, or snuff. Snuff users, for example, are 50 times more likely to develop cancers of the cheek or gum than nonusers.
C. Diet
Diet can also contribute to cancer. Saturated fats from red meats, such as hamburger or steak, and high-fat dairy products are linked with several cancers. High salt intake increases the risk of stomach cancer. Adult obesity increases the risk for cancer of the uterus in women and also appears to increase the risk for cancers in the breast, colon, kidney, and gallbladder. Alcohol consumption increases the risk of cancer of the esophagus and stomach, especially when combined with smoking.
D. Pathogens
Some carcinogens are living organisms. Certain viruses, bacteria, and parasites account for about 15 percent of all cancer deaths in the United States. Cancer-causing viruses include the human papillomavirus (HPV), a sexually transmitted virus responsible for 70 to 80 percent of all cases of cancer of the cervix. Hepatitis B and C viruses cause almost 80 percent of all liver cancer in the world. Epstein-Barr virus can also be carcinogenic, causing cancer of the lymphatic system. Human immunodeficiency virus (HIV) or a type of herpesvirus can lead to rare cancers of the lymphatic and circulatory systems. Helicobacter pylori, a bacterium associated with stomach ulcers, likely causes cancer of the stomach. Researchers have linked a polyomavirus to a rare, aggressive form of skin cancer called Merkel cell carcinoma.
In developing countries, parasitic organisms are major carcinogens. In parts of Africa, China, and southern Asia, infestation with the liver fluke Clonorchis sinensis causes a form of liver cancer. In North Africa, infection with the parasite Schistosoma haematobium causes cancer of the bladder.
E. Radiation
Exposure to electromagnetic radiation, invisible, high-energy light waves such as sunlight and X rays, accounts for a small percentage of cancer deaths (see Radiation Effects, Biological). Most cancer deaths from radiation are from skin cancer, which is triggered by too much sun exposure. Sunlight that reaches the Earth’s surface contains two kinds of ultraviolet (UV) radiation. UV-A and UV-B both contribute to sunburn and skin cancer as well as to conditions such as premature wrinkling of the skin. Depletion of the ozone layer, which absorbs ultraviolet radiation in the upper atmosphere, will continue to increase skin damage and skin cancer rates in the future.
Radon, a colorless, odorless, radioactive gas, seeps from the Earth in some regions of the United States. Breathing the gas over a long period has been linked to a small number of lung cancer cases. Providing adequate air circulation in a building reduces exposure to radon.
Infrequently, radiation exposure associated with medical treatments, such as therapeutic radiology, leads to cancer.
F. Environmental and Occupational Chemicals
Air pollution, water pollution, and pollutants in the soil contribute particularly to lung and bladder cancer. Lung cancer rates are generally higher in cities, where increased industry and automobile traffic produce air pollution. Some people encounter carcinogenic chemicals in their working environment. Occupational carcinogens include such industrial chemicals as benzene, asbestos, vinyl chloride, aniline dyes, arsenic, and certain petroleum products (see Occupational and Environmental Disease).
Monday, November 22, 2010
For woman only:How to lose ugly fat and become beautiful slim in 21 days
OBESITY.
Obesity, medical condition characterized by storage of excess body fat. The human body naturally stores fat tissue under the skin and around organs and joints. Fat is critical for good health because it is a source of energy when the body lacks the energy necessary to sustain life processes, and it provides insulation and protection for internal organs. But the accumulation of too much fat in the body is associated with a variety of health problems. Studies show that individuals who are overweight or obese run a greater risk of developing diabetes mellitus, hypertension, coronary heart disease, stroke, arthritis, and some forms of cancer.
MEASURING OBESITY
The body mass index (BMI) is commonly used to determine desirable body weights. BMI is a measure of an adult’s weight in relation to height, and it is calculated metrically as weight divided by height squared (kg/m2). People with a BMI of 25.0 to 29.9 are considered overweight and people with a BMI of 30 or above are considered obese .
Body mass index only provides a rough estimate of desirable weight, however. Physicians recognize that many other factors besides height affect weight. Weight alone may not be an indicator of fat, as in the case of a bodybuilder who may have a high BMI because of a high percentage of muscle tissue, which weighs more than fat. Likewise, a person with a sedentary lifestyle may be within a desirable weight range but have excess fat tissue. In general, however, the higher the BMI, the greater the risk for developing serious medical
COMPLICATIONS OF OBESITY
Obesity increases the risk of developing disease. According to the National Institute of Diabetes and Digestive and Kidney Diseases, almost 70 percent of heart disease cases in the United States are linked to excess body fat, and obese people are more than twice as likely to develop hypertension. The risk of medical complications, particularly heart disease, increases when body fat is distributed around the waist, especially in the abdomen. This type of upper body fat distribution is more common in men than in women.
Obese women are at nearly twice the risk for developing breast cancer, and all obese people have a 42 percent higher chance of developing colorectal cancer. Almost 80 percent of patients with Type 2 diabetes mellitus, also known as noninsulin-dependent diabetes mellitus, are obese.
Obese people also experience social and psychological problems. Stereotypes about “fat” people often translate into discriminatory practices in education, employment, and social relationships.
The consequences of being obese in a world preoccupied with being thin
are especially severe for women, whose appearances are often judged against an ideal of exaggerated slenderness.
CAUSES OF OBESITY
A calorie is the unit used to measure the energy value of food and the energy used by the body to maintain normal functions. When the calories from food intake equal the calories of energy the body uses, weight remains constant. But when a person consumes more calories than the body needs the body stores those additional calories as fat, causing subsequent weight gain. Consuming about 3,500 calories more than what the body needs results in a weight gain of 0.45 kg (1 lb) of fat
A. BIOLOGICAL FACTORS
Research has revealed the important role of biological factors in the regulation of body weight. For instance, basal metabolic rate, the minimum energy required to maintain normal body function, affects body weight and weight loss because some individuals naturally use more calories to sustain basic body processes. The size and number of an individual’s fat cells also help determine the amount of weight loss that is possible.
B. GENETICS FACTORS
Obesity is partially determined by a person’s genetic makeup. One groundbreaking study published in 1986 followed children who were adopted shortly after birth. The adoptees grew up to achieve adult weights that were more similar to their biological parents than their adoptive parents, indicating the influence of a person’s genetic makeup in determining body weight.
Scientists are unclear about which genes affect human obesity. More than 250 genes that may play a role in obesity have been identified in mice and humans. Researchers believe that the cause of obesity in humans is complicated and most likely involves the interactions of multiple genes with lifestyle factors such as diet and physical activity
C. LIFESTYE
Changing lifestyles over the last century, including increased calorie consumption and reduced physical activity, have played a key role in the prevalence of obesity seen today. In the United States and other developed nations, the availability of wider food options has contributed to a change in eating habits. Grocery stores stock their shelves with a greater selection of products. Prepackaged foods, soft drinks, and fast-food restaurants have become more accessible. While such food choices offer convenience, they also tend to be high in fat, sugar, and calories.
Portion size has also increased. People eat more during a meal or snack because of larger portion sizes. Surveys indicate that people eat at restaurants more frequently than in the 1970s and restaurants typically serve larger portions of food than those served at home. In the United States, experts believe that high-calorie food choices and larger portions have become the basis of the typical diet, resulting in excessive calorie intake and increasing the prevalence of obesity.
Both adults and children spend less time devoted to exercise as a result of longer work hours at sedentary jobs, a decline in physical education programs in schools, and increased participation in sedentary recreational activities such as browsing the Internet, playing video games, and watching television. In addition, many of the laborsaving devices of the modern lifestyle, such as cars, elevators, personal computers, and remote controls, promote a sedentary lifestyle. According to some studies, more than 26 percent of adults reported no leisure-time physical activity. This lack of physical activity has reduced the overall amount of energy expended in the course of a day, contributing to the development of obesity.
TREATMENT FOR OBESITY
Obesity can become a chronic lifelong condition caused by overeating, physical inactivity, and even genetic makeup. No matter what the cause, however, obesity can be prevented or managed with a combination of diet, exercise, behavior modification, and in severe cases, weight-loss medications and surgery.
A. DIETS
The most common and conservative treatment for obesity utilizes a nutritionally balanced, low calorie diet. Most health-care professionals and commercial weight-loss programs recommend diets consisting of 1,200 to 1,500 calories per day, usually in the following proportions: 60 percent carbohydrate, 30 percent fat, and 10 percent protein. Research from university obesity treatment centers indicates that patients who follow a low calorie diet lose 10 percent of their initial weight in 20 weeks. Without further treatment, however, patients usually regain one-third of the weight in the following year.
A more aggressive approach for persons who are more than 20 kg (40 lb) overweight includes very low calorie diets ranging from 400 to 800 calories per day. These diets are usually based on four to five servings of a liquid formula each day. Candidates must be carefully screened and medically supervised while on the diet. People on very low calorie diets lose approximately 15 to 20 percent of their initial body weight in 16 weeks. Once they go off a very low calorie diet, they typically regain approximately one-half of that weight within a year.
Meal replacements are liquid shakes or portion-controlled meals that are substituted for one or two meals a day. They are typically used as part of a 1,200 to 1,500 calorie diet. Studies have shown that meal replacements are often more effective than very low
Calories diets, resulting in an increase in the amount of initial weight loss and enabling dieters to maintain their weight loss. Unlike very low calorie diets, meal replacements do not require that candiThe most common and conservative treatment for obesity utilizes a nutritionally balanced, low calorie diet. Most health-care professionals and commercial weight-loss programs recommend diets consisting of 1,200 to 1,500 calories per day, usually in the following proportions: 60 percent carbohydrate, 30 percent fat, and 10 percent protein. Research from university obesity treatment centers indicates that patients who follow a low calorie diet lose 10 percent of their initial weight in 20 weeks. Without further treatment, however, patients usually regain one-third of the weight in the following year.
A more aggressive approach for persons who are more than 20 kg (40 lb) overweight includes very low calorie diets ranging from 400 to 800 calories per day. These diets are usually based on four to five servings of a liquid formula each day. Candidates must be carefully screened and medically supervised while on the diet. People on very low calorie diets lose approximately 15 to 20 percent of their initial body weight in 16 weeks. Once they go off a very low calorie diet, they typically regain approximately one-half of that weight within a year.
Meal replacements are liquid shakes or portion-controlled meals that are substituted for one or two meals a day. They are typically used as part of a 1,200 to 1,500 calorie diet. Studies have shown that meal replacements are often more effective than very low calories diets, resulting in an increase in the amount of initial weight loss and enabling dieters to maintain their weight loss. Unlike very low calorie diets, meal replacements do not require that candidates receive extensive medical monitoring.
B. EXERCISE
Caloric restriction alone will not produce long-term weight loss. While the data from studies on the effect of exercise for short-term weight loss are contradictory, research clearly indicates that regular exercise is the single best predictor for achieving long-term weight control. Regular exercise will also improve some of the medical conditions associated with obesity, including elevated blood cholesterol, hypertension, and diabetes mellitus.
C. BEHAVOIR MODIFICATION
Many eating and exercise habits combine to promote weight gain. Certain times, places, activities, and emotions may be linked to periods of overeating or inactivity. Many obesity treatment programs recommend individuals keep a food diary that records all food or drink consumed when and with whom it was consumed, and the mood or precipitating events that trigger eating.
After one to two weeks, the diary may reveal a pattern of activities or negative emotions that lead to overeating. Once these eating cues are identified, techniques can be developed and practiced to prevent unwanted eating habits.
D. WAISTE -LOSS MEDICATIONS
Weight-loss medications of any type are only appropriate for people with a BMI of 30 or above, or a BMI of 27 or above accompanied by weight-related medical conditions such as diabetes mellitus or hypertension. Amphetamine drugs were formerly prescribed to combat obesity, but their well-documented side effects, including insomnia, anxiety, and tolerance (the need to take higher and higher doses to continue to produce the same effect), made them less popular by the late 1970s.
A renewed scientific and commercial interest in weight-loss medications was prompted by the approval by the Food and Drug Administration (FDA) of the appetite suppressant dexfenfluramine (sold under the brand name Redux) in 1996. Dexfenfluramine was the first weight-loss medication approved in the United States in over 20 years and the first ever approved for maintaining weight loss. Although never approved for long-term use by the FDA, a combination of two drugs, phentermine and fenfluramine, or phentermine and dexflenfluramine, popularly known as fen-phen, was used by millions of Americans to promote weight loss. Fenfluramine and dexfenfluramine were eventually associated with valvular heart disease, and the manufacturer withdrew these medications from the marketplace in 1997.
The FDA has approved two medications, sibutramine and orlistat, for long-term use in the treatment of obesity. Sibutramine (sold under the brand name Meridia) increases fullness, making the required dietary changes for weight loss and the maintenance of weight loss easier to accomplish. Unlike dexfenfluramine and fenfluramine, sibutramine does not appear to be associated with valvular heart disease, although a small number of patients may develop significant increases in blood pressure. Orlistat (sold under the brand name Xenical) works by blocking the absorption of fat. Scientists are also investigating the hormone leptin, which plays a role in obesity in mice, as a possible treatment for obesity in humans.
Over a six-month period, weight-loss medications may result in a 10-percent body weight reduction. Weight loss slows or stops after six months, and discontinuing medication usually causes weight regain. The continued use of medications keeps most of the lost weight from returning for two years. Many experts recommend that medications for weight control be used continuously, like medications for diabetes mellitus and hypertension. Unfortunately, few studies have examined the consequences of long-term use of weight-control medications.
E. SURGERY
Surgery may be a weight-loss option for patients who are severely obese (with a BMI of 40 or above) and suffer from serious medical complications due to weight. While the number of people in the United States who qualify for surgery remains small, the percentage of Americans with a BMI of 40 or above increased from less than 1 percent in 1990 to 2.2 percent in 2000.
There are two accepted surgical procedures for reducing body weight: gastroplasty and gastric bypass. Although these two procedures use different surgical methods, they both reduce the stomach to a pouch that is smaller than a chicken’s egg, drastically limiting the amount of food that can be consumed at one time. Surgery produces 25 to 35 percent reductions in weight over the first year and most of this weight loss is maintained five years after surgery. More importantly, the serious medical conditions that accompany extreme obesity improve significantly. Surgery is not without risk and should be performed by skilled surgeons who also provide patients with a comprehensive program for long-term weight control.
NEW DIRECTION FOR OBESITY
The weight-loss goal of most obese dieters is to achieve an ideal weight often defined by celebrities and models in fashion magazines. But research over the last decade indicates that a 5- to 10-percent reduction in body weight is sufficient to significantly improve medical conditions associated with obesity, such as hypertension, diabetes mellitus, and elevated cholesterol levels. These health improvements occur even though patients may still be overweight.
These new weight-loss goals may be difficult for obese people to accept. Obese people often seek weight-loss goals that may be biologically impossible to achieve or, if achieved, cannot be maintained. One study of overweight women found that the average weight goal was a 30 percent reduction in body weight. Yet no obesity treatment produces long-term, maintainable weight losses significant enough for patients to reach this goal. Physicians and commercial weight-loss programs need to help obese people feel successful when more modest reductions in weight and significant improvements in health are achieved, many health experts believe.
Obesity, medical condition characterized by storage of excess body fat. The human body naturally stores fat tissue under the skin and around organs and joints. Fat is critical for good health because it is a source of energy when the body lacks the energy necessary to sustain life processes, and it provides insulation and protection for internal organs. But the accumulation of too much fat in the body is associated with a variety of health problems. Studies show that individuals who are overweight or obese run a greater risk of developing diabetes mellitus, hypertension, coronary heart disease, stroke, arthritis, and some forms of cancer.
MEASURING OBESITY
The body mass index (BMI) is commonly used to determine desirable body weights. BMI is a measure of an adult’s weight in relation to height, and it is calculated metrically as weight divided by height squared (kg/m2). People with a BMI of 25.0 to 29.9 are considered overweight and people with a BMI of 30 or above are considered obese .
Body mass index only provides a rough estimate of desirable weight, however. Physicians recognize that many other factors besides height affect weight. Weight alone may not be an indicator of fat, as in the case of a bodybuilder who may have a high BMI because of a high percentage of muscle tissue, which weighs more than fat. Likewise, a person with a sedentary lifestyle may be within a desirable weight range but have excess fat tissue. In general, however, the higher the BMI, the greater the risk for developing serious medical
COMPLICATIONS OF OBESITY
Obesity increases the risk of developing disease. According to the National Institute of Diabetes and Digestive and Kidney Diseases, almost 70 percent of heart disease cases in the United States are linked to excess body fat, and obese people are more than twice as likely to develop hypertension. The risk of medical complications, particularly heart disease, increases when body fat is distributed around the waist, especially in the abdomen. This type of upper body fat distribution is more common in men than in women.
Obese women are at nearly twice the risk for developing breast cancer, and all obese people have a 42 percent higher chance of developing colorectal cancer. Almost 80 percent of patients with Type 2 diabetes mellitus, also known as noninsulin-dependent diabetes mellitus, are obese.
Obese people also experience social and psychological problems. Stereotypes about “fat” people often translate into discriminatory practices in education, employment, and social relationships.
The consequences of being obese in a world preoccupied with being thin
are especially severe for women, whose appearances are often judged against an ideal of exaggerated slenderness.
CAUSES OF OBESITY
A calorie is the unit used to measure the energy value of food and the energy used by the body to maintain normal functions. When the calories from food intake equal the calories of energy the body uses, weight remains constant. But when a person consumes more calories than the body needs the body stores those additional calories as fat, causing subsequent weight gain. Consuming about 3,500 calories more than what the body needs results in a weight gain of 0.45 kg (1 lb) of fat
A. BIOLOGICAL FACTORS
Research has revealed the important role of biological factors in the regulation of body weight. For instance, basal metabolic rate, the minimum energy required to maintain normal body function, affects body weight and weight loss because some individuals naturally use more calories to sustain basic body processes. The size and number of an individual’s fat cells also help determine the amount of weight loss that is possible.
B. GENETICS FACTORS
Obesity is partially determined by a person’s genetic makeup. One groundbreaking study published in 1986 followed children who were adopted shortly after birth. The adoptees grew up to achieve adult weights that were more similar to their biological parents than their adoptive parents, indicating the influence of a person’s genetic makeup in determining body weight.
Scientists are unclear about which genes affect human obesity. More than 250 genes that may play a role in obesity have been identified in mice and humans. Researchers believe that the cause of obesity in humans is complicated and most likely involves the interactions of multiple genes with lifestyle factors such as diet and physical activity
C. LIFESTYE
Changing lifestyles over the last century, including increased calorie consumption and reduced physical activity, have played a key role in the prevalence of obesity seen today. In the United States and other developed nations, the availability of wider food options has contributed to a change in eating habits. Grocery stores stock their shelves with a greater selection of products. Prepackaged foods, soft drinks, and fast-food restaurants have become more accessible. While such food choices offer convenience, they also tend to be high in fat, sugar, and calories.
Portion size has also increased. People eat more during a meal or snack because of larger portion sizes. Surveys indicate that people eat at restaurants more frequently than in the 1970s and restaurants typically serve larger portions of food than those served at home. In the United States, experts believe that high-calorie food choices and larger portions have become the basis of the typical diet, resulting in excessive calorie intake and increasing the prevalence of obesity.
Both adults and children spend less time devoted to exercise as a result of longer work hours at sedentary jobs, a decline in physical education programs in schools, and increased participation in sedentary recreational activities such as browsing the Internet, playing video games, and watching television. In addition, many of the laborsaving devices of the modern lifestyle, such as cars, elevators, personal computers, and remote controls, promote a sedentary lifestyle. According to some studies, more than 26 percent of adults reported no leisure-time physical activity. This lack of physical activity has reduced the overall amount of energy expended in the course of a day, contributing to the development of obesity.
TREATMENT FOR OBESITY
Obesity can become a chronic lifelong condition caused by overeating, physical inactivity, and even genetic makeup. No matter what the cause, however, obesity can be prevented or managed with a combination of diet, exercise, behavior modification, and in severe cases, weight-loss medications and surgery.
A. DIETS
The most common and conservative treatment for obesity utilizes a nutritionally balanced, low calorie diet. Most health-care professionals and commercial weight-loss programs recommend diets consisting of 1,200 to 1,500 calories per day, usually in the following proportions: 60 percent carbohydrate, 30 percent fat, and 10 percent protein. Research from university obesity treatment centers indicates that patients who follow a low calorie diet lose 10 percent of their initial weight in 20 weeks. Without further treatment, however, patients usually regain one-third of the weight in the following year.
A more aggressive approach for persons who are more than 20 kg (40 lb) overweight includes very low calorie diets ranging from 400 to 800 calories per day. These diets are usually based on four to five servings of a liquid formula each day. Candidates must be carefully screened and medically supervised while on the diet. People on very low calorie diets lose approximately 15 to 20 percent of their initial body weight in 16 weeks. Once they go off a very low calorie diet, they typically regain approximately one-half of that weight within a year.
Meal replacements are liquid shakes or portion-controlled meals that are substituted for one or two meals a day. They are typically used as part of a 1,200 to 1,500 calorie diet. Studies have shown that meal replacements are often more effective than very low
Calories diets, resulting in an increase in the amount of initial weight loss and enabling dieters to maintain their weight loss. Unlike very low calorie diets, meal replacements do not require that candiThe most common and conservative treatment for obesity utilizes a nutritionally balanced, low calorie diet. Most health-care professionals and commercial weight-loss programs recommend diets consisting of 1,200 to 1,500 calories per day, usually in the following proportions: 60 percent carbohydrate, 30 percent fat, and 10 percent protein. Research from university obesity treatment centers indicates that patients who follow a low calorie diet lose 10 percent of their initial weight in 20 weeks. Without further treatment, however, patients usually regain one-third of the weight in the following year.
A more aggressive approach for persons who are more than 20 kg (40 lb) overweight includes very low calorie diets ranging from 400 to 800 calories per day. These diets are usually based on four to five servings of a liquid formula each day. Candidates must be carefully screened and medically supervised while on the diet. People on very low calorie diets lose approximately 15 to 20 percent of their initial body weight in 16 weeks. Once they go off a very low calorie diet, they typically regain approximately one-half of that weight within a year.
Meal replacements are liquid shakes or portion-controlled meals that are substituted for one or two meals a day. They are typically used as part of a 1,200 to 1,500 calorie diet. Studies have shown that meal replacements are often more effective than very low calories diets, resulting in an increase in the amount of initial weight loss and enabling dieters to maintain their weight loss. Unlike very low calorie diets, meal replacements do not require that candidates receive extensive medical monitoring.
B. EXERCISE
Caloric restriction alone will not produce long-term weight loss. While the data from studies on the effect of exercise for short-term weight loss are contradictory, research clearly indicates that regular exercise is the single best predictor for achieving long-term weight control. Regular exercise will also improve some of the medical conditions associated with obesity, including elevated blood cholesterol, hypertension, and diabetes mellitus.
C. BEHAVOIR MODIFICATION
Many eating and exercise habits combine to promote weight gain. Certain times, places, activities, and emotions may be linked to periods of overeating or inactivity. Many obesity treatment programs recommend individuals keep a food diary that records all food or drink consumed when and with whom it was consumed, and the mood or precipitating events that trigger eating.
After one to two weeks, the diary may reveal a pattern of activities or negative emotions that lead to overeating. Once these eating cues are identified, techniques can be developed and practiced to prevent unwanted eating habits.
D. WAISTE -LOSS MEDICATIONS
Weight-loss medications of any type are only appropriate for people with a BMI of 30 or above, or a BMI of 27 or above accompanied by weight-related medical conditions such as diabetes mellitus or hypertension. Amphetamine drugs were formerly prescribed to combat obesity, but their well-documented side effects, including insomnia, anxiety, and tolerance (the need to take higher and higher doses to continue to produce the same effect), made them less popular by the late 1970s.
A renewed scientific and commercial interest in weight-loss medications was prompted by the approval by the Food and Drug Administration (FDA) of the appetite suppressant dexfenfluramine (sold under the brand name Redux) in 1996. Dexfenfluramine was the first weight-loss medication approved in the United States in over 20 years and the first ever approved for maintaining weight loss. Although never approved for long-term use by the FDA, a combination of two drugs, phentermine and fenfluramine, or phentermine and dexflenfluramine, popularly known as fen-phen, was used by millions of Americans to promote weight loss. Fenfluramine and dexfenfluramine were eventually associated with valvular heart disease, and the manufacturer withdrew these medications from the marketplace in 1997.
The FDA has approved two medications, sibutramine and orlistat, for long-term use in the treatment of obesity. Sibutramine (sold under the brand name Meridia) increases fullness, making the required dietary changes for weight loss and the maintenance of weight loss easier to accomplish. Unlike dexfenfluramine and fenfluramine, sibutramine does not appear to be associated with valvular heart disease, although a small number of patients may develop significant increases in blood pressure. Orlistat (sold under the brand name Xenical) works by blocking the absorption of fat. Scientists are also investigating the hormone leptin, which plays a role in obesity in mice, as a possible treatment for obesity in humans.
Over a six-month period, weight-loss medications may result in a 10-percent body weight reduction. Weight loss slows or stops after six months, and discontinuing medication usually causes weight regain. The continued use of medications keeps most of the lost weight from returning for two years. Many experts recommend that medications for weight control be used continuously, like medications for diabetes mellitus and hypertension. Unfortunately, few studies have examined the consequences of long-term use of weight-control medications.
E. SURGERY
Surgery may be a weight-loss option for patients who are severely obese (with a BMI of 40 or above) and suffer from serious medical complications due to weight. While the number of people in the United States who qualify for surgery remains small, the percentage of Americans with a BMI of 40 or above increased from less than 1 percent in 1990 to 2.2 percent in 2000.
There are two accepted surgical procedures for reducing body weight: gastroplasty and gastric bypass. Although these two procedures use different surgical methods, they both reduce the stomach to a pouch that is smaller than a chicken’s egg, drastically limiting the amount of food that can be consumed at one time. Surgery produces 25 to 35 percent reductions in weight over the first year and most of this weight loss is maintained five years after surgery. More importantly, the serious medical conditions that accompany extreme obesity improve significantly. Surgery is not without risk and should be performed by skilled surgeons who also provide patients with a comprehensive program for long-term weight control.
NEW DIRECTION FOR OBESITY
The weight-loss goal of most obese dieters is to achieve an ideal weight often defined by celebrities and models in fashion magazines. But research over the last decade indicates that a 5- to 10-percent reduction in body weight is sufficient to significantly improve medical conditions associated with obesity, such as hypertension, diabetes mellitus, and elevated cholesterol levels. These health improvements occur even though patients may still be overweight.
These new weight-loss goals may be difficult for obese people to accept. Obese people often seek weight-loss goals that may be biologically impossible to achieve or, if achieved, cannot be maintained. One study of overweight women found that the average weight goal was a 30 percent reduction in body weight. Yet no obesity treatment produces long-term, maintainable weight losses significant enough for patients to reach this goal. Physicians and commercial weight-loss programs need to help obese people feel successful when more modest reductions in weight and significant improvements in health are achieved, many health experts believe.
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Wednesday, November 17, 2010
infertility from nature
Infertility from nature’s perspective.
Test performed on Men:
Semen analysis:
A sample of semen is examined not longer after ejaculation. It is tested for sperm motility (% of sperm that are swimming) and morphology (% that have normal shape).
Sperm penetration test:
This is the ability to penetrate hamster egg cells which will indicate the sperm’s ability to penetrate the spouse eggs?
Endocrine test:
Blood test are done to determine the levels of follicle stimulating hormone (FSH), luteinizing hormone (LH) and thyroid hormones (T). LH levels are tested if T levels are abnormal.
Post coital test:
The spouse have sex and the ejaculation are tested for surviving sperms.
X-ray:
To test for damage done to the ducts which are responsible from transporting sperms to the penis.
Testicular biopsy:
A sample is examined to determine the condition of sperm or if the sperm are being made.
Tests performed on women:
Endometrial biopsy:
A sample of endometrium (lining of the uterus) is taken in the later part of the menstrual cycle and tested to see if there is enough progesterone in the lining as it matures. If not the condition is called luteal phase defect. Hormonal drugs are given to correct this condition.
FSH Test:
Blood sample is taken on the third day of menstrual cycle to test for FHH level. If FSH level is high, then the pregnancy is most unlikely to occur.
Hysterosal Pingo-gram (HSG):
A dye is inserted through the cervix into the fallopian tubes and uterus and an x-ray is taken to determine if the tubes are opened and it also enables us to know if the uterus has a normal shape.
Laparoscopy:
A surgical procedure in which a physician examines the productive organs of the woman by means of tiny scope, if gear tissue or Endometrial buildup is found, it can be removed by means of scope.
Post coital test:
The partners have sex (PCT, SIMS-Huhner test) two to eight hours before the test sample of cervical mucus and tissue is removed and examine to determine whether the mucus or cervix is prohibiting fertilization. The test is same as Pap smear test.
Transvaginal ultrasound:
A probe is inserted into the vagina to look for fibroid tumors or ovarian cysts.
These test are conducted by experts where investigation reveal pregnancy inhibiting findings, they are quickly treated, pregnancy may occur within a short while.
NOTE:
You must have a mental attitude. Get a physician to work with, who will conduct all the test. You also need to get a herbal medicine practitioner who has the capacity to work on the physician’s and laboratory reports.
…BE PATIENTS WITH YOURSELf AND YOUR SPOUSE.
Test performed on Men:
Semen analysis:
A sample of semen is examined not longer after ejaculation. It is tested for sperm motility (% of sperm that are swimming) and morphology (% that have normal shape).
Sperm penetration test:
This is the ability to penetrate hamster egg cells which will indicate the sperm’s ability to penetrate the spouse eggs?
Endocrine test:
Blood test are done to determine the levels of follicle stimulating hormone (FSH), luteinizing hormone (LH) and thyroid hormones (T). LH levels are tested if T levels are abnormal.
Post coital test:
The spouse have sex and the ejaculation are tested for surviving sperms.
X-ray:
To test for damage done to the ducts which are responsible from transporting sperms to the penis.
Testicular biopsy:
A sample is examined to determine the condition of sperm or if the sperm are being made.
Tests performed on women:
Endometrial biopsy:
A sample of endometrium (lining of the uterus) is taken in the later part of the menstrual cycle and tested to see if there is enough progesterone in the lining as it matures. If not the condition is called luteal phase defect. Hormonal drugs are given to correct this condition.
FSH Test:
Blood sample is taken on the third day of menstrual cycle to test for FHH level. If FSH level is high, then the pregnancy is most unlikely to occur.
Hysterosal Pingo-gram (HSG):
A dye is inserted through the cervix into the fallopian tubes and uterus and an x-ray is taken to determine if the tubes are opened and it also enables us to know if the uterus has a normal shape.
Laparoscopy:
A surgical procedure in which a physician examines the productive organs of the woman by means of tiny scope, if gear tissue or Endometrial buildup is found, it can be removed by means of scope.
Post coital test:
The partners have sex (PCT, SIMS-Huhner test) two to eight hours before the test sample of cervical mucus and tissue is removed and examine to determine whether the mucus or cervix is prohibiting fertilization. The test is same as Pap smear test.
Transvaginal ultrasound:
A probe is inserted into the vagina to look for fibroid tumors or ovarian cysts.
These test are conducted by experts where investigation reveal pregnancy inhibiting findings, they are quickly treated, pregnancy may occur within a short while.
NOTE:
You must have a mental attitude. Get a physician to work with, who will conduct all the test. You also need to get a herbal medicine practitioner who has the capacity to work on the physician’s and laboratory reports.
…BE PATIENTS WITH YOURSELf AND YOUR SPOUSE.
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Monday, November 15, 2010
Friday, November 12, 2010
Treatment for leukemia
Treatment for leukemia
Treatment of leukemia depends on the type and extent of the disease and is tailored to each individual patient. In general, chemotherapy—the use of drugs that kill rapidly dividing cells—is the mainstay of treatment for both acute and chronic leukemias. In acute leukemias, chemotherapy is very intensive and uses several drugs, either simultaneously or sequentially, in order to kill as many leukemic cells as possible. Antibiotics and transfusions of red cells and platelets help sustain patients whose blood counts are dangerously low because they are receiving intensive chemotherapy.
Sometimes radiation is used to shrink collections of leukemic cells that accumulate in various parts of the body, such as on the lining of the brain and spinal cord in acute lymphocytic leukemia, or within lymph nodes in chronic lymphocytic leukemia. If left untreated, collections of cells on the lining of the brain and spinal cord can cause headache, blurred vision, and confusion, and elsewhere in the body can cause swelling and tenderness of the affected area.
Particularly in young patients, if doctors determine that chemotherapy alone is not likely to be successful or if patients relapse after chemotherapy, allogeneic (genetically different) stem cell transplantation may be performed. In this procedure, very intensive total body radiation or very high doses of chemotherapy or both are used. The chemotherapy and radiation are designed to destroy all the leukemic cells in a patient’s body; however, this treatment also destroys the blood-forming system in the patient’s bone marrow. For this reason, healthy stem cells, the cells in bone marrow that enable long-term formation of blood, must then be infused into a patient to replenish the blood-forming system. The stem cells must come from an immunologically matched donor, usually a sibling, but if a sibling match is unavailable, occasionally an unrelated donor may be sought. The latter can be identified from a database of volunteer donors. These databases can be searched for a person with an identical or very close tissue type match. Formerly, stem cells could only be transplanted from the bone marrow of the donor. The procedure was known as bone marrow transplantation. Recent advances now make it possible to recover stem cells from blood, or from the placenta and umbilical cord blood (“cord blood”) after delivery of a newborn, making the transplant procedure much simpler and less risky for the donor.
Cord-blood stem cells are frozen, kept in a “bank,” and can be used later for a patient in need. The number of stem cells in these samples may be insufficient for larger adults and are used most commonly for children or smaller adults who require a transplant and are in need of a matched, unrelated donor.
An unexpected effect of allogeneic stem cell transplantation is what is known as graft-versus-leukemia effect. The immune cells of the donor recognize minor tissue type antigens (the proteins that produce antibodies) that do not match the recipient’s. These donor immune cells attack the recipient’s tissues, including both leukemia cells and normal tissues. The attack against the recipient’s normal tissues is referred to as graft-versus-host disease. This attack can be acute or chronic, and very mild or very severe. It is a serious, unwanted complication of allogeneic stem cell transplantation. Graft-versus-leukemia-cells, on the other hand, is a desirable effect and is responsible in part for some of the beneficial effects of transplantation, especially in patients who received transplants to treat acute or chronic myelocytic leukemia.
Transplantation is most effective in children and young adults; in older adults it is often too hazardous a procedure to apply. An approach called non-myeloablative stem cell transplantation is being tested in older patients. Here very mild pretreatment with chemotherapy or irradiation is used, while anti-immune therapy is relied on to prevent the recipient’s immune system from rejecting the donor’s stem cells. The graft-versus-leukemia effect is relied on as a substitute for the very intensive therapy given before a standard transplant for leukemia
Immunotherapy is a promising new approach to treating leukemia. In this technique, highly specific molecules known as monoclonal antibodies are manufactured in the laboratory to target molecules on the surface of leukemic cells. The antibodies themselves may kill the leukemic cells, or a radioactive substance or cell toxin attached to the antibodies may kill the leukemic cells, when injected intravenously into a patient. This method provides a convenient means of delivering the radioactive or toxic substance directly to leukemic cells, where it may kill these cells with minimal effect on healthy cells.
The goal in treating acute leukemias is to kill enough leukemic cells to produce a remission, meaning that the production of healthy blood cells is no longer suppressed, blood cell counts return to normal, and the patient’s symptoms diminish. At that stage, further therapy is used to try to prolong remission or achieve a cure. About 80 percent of children with acute lymphocytic leukemia are cured. Cure rates in acute myelocytic leukemia are estimated to be about 40 percent in children but are much lower in adults depending on their age. Since most patients are over 65 years when they develop the disease, cures are infrequent.
In the chronic leukemias, cures are very infrequent, but today’s chemotherapy regimens have increased the average survival in these patients from about three years to more than six years. Chronic lymphocytic leukemia in its most indolent form may not require treatment and may not progress or be a serious health consequence for the patient. In patients with active or progressive disease, several new drugs and types of monoclonal antibodies are available to treat the disease. In chronic myelocytic leukemia, a dramatic advance in therapy involves the introduction of a drug that specifically targets the leukemia-causing change in the marrow cell. The introduction of this treatment has been projected to increase survival to more than a decade on average. Young patients with the disease who have an appropriate stem cell donor can be cured with stem cell transplantation.
Treatment of leukemia depends on the type and extent of the disease and is tailored to each individual patient. In general, chemotherapy—the use of drugs that kill rapidly dividing cells—is the mainstay of treatment for both acute and chronic leukemias. In acute leukemias, chemotherapy is very intensive and uses several drugs, either simultaneously or sequentially, in order to kill as many leukemic cells as possible. Antibiotics and transfusions of red cells and platelets help sustain patients whose blood counts are dangerously low because they are receiving intensive chemotherapy.
Sometimes radiation is used to shrink collections of leukemic cells that accumulate in various parts of the body, such as on the lining of the brain and spinal cord in acute lymphocytic leukemia, or within lymph nodes in chronic lymphocytic leukemia. If left untreated, collections of cells on the lining of the brain and spinal cord can cause headache, blurred vision, and confusion, and elsewhere in the body can cause swelling and tenderness of the affected area.
Particularly in young patients, if doctors determine that chemotherapy alone is not likely to be successful or if patients relapse after chemotherapy, allogeneic (genetically different) stem cell transplantation may be performed. In this procedure, very intensive total body radiation or very high doses of chemotherapy or both are used. The chemotherapy and radiation are designed to destroy all the leukemic cells in a patient’s body; however, this treatment also destroys the blood-forming system in the patient’s bone marrow. For this reason, healthy stem cells, the cells in bone marrow that enable long-term formation of blood, must then be infused into a patient to replenish the blood-forming system. The stem cells must come from an immunologically matched donor, usually a sibling, but if a sibling match is unavailable, occasionally an unrelated donor may be sought. The latter can be identified from a database of volunteer donors. These databases can be searched for a person with an identical or very close tissue type match. Formerly, stem cells could only be transplanted from the bone marrow of the donor. The procedure was known as bone marrow transplantation. Recent advances now make it possible to recover stem cells from blood, or from the placenta and umbilical cord blood (“cord blood”) after delivery of a newborn, making the transplant procedure much simpler and less risky for the donor.
Cord-blood stem cells are frozen, kept in a “bank,” and can be used later for a patient in need. The number of stem cells in these samples may be insufficient for larger adults and are used most commonly for children or smaller adults who require a transplant and are in need of a matched, unrelated donor.
An unexpected effect of allogeneic stem cell transplantation is what is known as graft-versus-leukemia effect. The immune cells of the donor recognize minor tissue type antigens (the proteins that produce antibodies) that do not match the recipient’s. These donor immune cells attack the recipient’s tissues, including both leukemia cells and normal tissues. The attack against the recipient’s normal tissues is referred to as graft-versus-host disease. This attack can be acute or chronic, and very mild or very severe. It is a serious, unwanted complication of allogeneic stem cell transplantation. Graft-versus-leukemia-cells, on the other hand, is a desirable effect and is responsible in part for some of the beneficial effects of transplantation, especially in patients who received transplants to treat acute or chronic myelocytic leukemia.
Transplantation is most effective in children and young adults; in older adults it is often too hazardous a procedure to apply. An approach called non-myeloablative stem cell transplantation is being tested in older patients. Here very mild pretreatment with chemotherapy or irradiation is used, while anti-immune therapy is relied on to prevent the recipient’s immune system from rejecting the donor’s stem cells. The graft-versus-leukemia effect is relied on as a substitute for the very intensive therapy given before a standard transplant for leukemia
Immunotherapy is a promising new approach to treating leukemia. In this technique, highly specific molecules known as monoclonal antibodies are manufactured in the laboratory to target molecules on the surface of leukemic cells. The antibodies themselves may kill the leukemic cells, or a radioactive substance or cell toxin attached to the antibodies may kill the leukemic cells, when injected intravenously into a patient. This method provides a convenient means of delivering the radioactive or toxic substance directly to leukemic cells, where it may kill these cells with minimal effect on healthy cells.
The goal in treating acute leukemias is to kill enough leukemic cells to produce a remission, meaning that the production of healthy blood cells is no longer suppressed, blood cell counts return to normal, and the patient’s symptoms diminish. At that stage, further therapy is used to try to prolong remission or achieve a cure. About 80 percent of children with acute lymphocytic leukemia are cured. Cure rates in acute myelocytic leukemia are estimated to be about 40 percent in children but are much lower in adults depending on their age. Since most patients are over 65 years when they develop the disease, cures are infrequent.
In the chronic leukemias, cures are very infrequent, but today’s chemotherapy regimens have increased the average survival in these patients from about three years to more than six years. Chronic lymphocytic leukemia in its most indolent form may not require treatment and may not progress or be a serious health consequence for the patient. In patients with active or progressive disease, several new drugs and types of monoclonal antibodies are available to treat the disease. In chronic myelocytic leukemia, a dramatic advance in therapy involves the introduction of a drug that specifically targets the leukemia-causing change in the marrow cell. The introduction of this treatment has been projected to increase survival to more than a decade on average. Young patients with the disease who have an appropriate stem cell donor can be cured with stem cell transplantation.
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