biologicals

A bioterrorism attack is the deliberate release of viruses, bacteria, or other germs to cause illness or death. These germs are often found in nature. But they can sometimes be made more harmful by increasing their ability to cause disease, spread, or resist medical treatment.

Biological agents spread through the air, water, or in food. Some can also spread from person to person. They can be very hard to detect. They don't cause illness for several hours or days. Scientists worry that anthrax, botulism, Ebola and other hemorrhagic fever viruses, plague, or smallpox could be used as biological agents.

Biodefense uses medical measures to protect people against bioterrorism. This includes medicines and vaccinations. It also includes medical research and preparations to defend against bioterrorist attacks.

Centers for Disease Control and Prevention

Immunotherapy is a cancer treatment that helps your immune system fight cancer. It is a type of biological therapy. Biological therapy uses substances that are made from living organisms, or versions of these substances that are made in a lab.

Doctors don't yet use immunotherapy as often as other cancer treatments, such as surgery, chemotherapy, and radiation therapy. But they do use immunotherapy for some types of cancer, and researchers are doing clinical trials to see whether it also works for other types.

When you have cancer, some of your cells begin to multiply without stopping. They spread into the surrounding tissues. One reason that the cancer cells can keep growing and spreading is that they are able to hide from your immune system. Some immunotherapies can "mark" your cancer cells. This makes it easier for your immune system to find and destroy the cells. It is a type of targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells. Other types of immunotherapies work by boosting your immune system to work better against cancer.

You could get immunotherapy intravenously (by IV), in pills or capsules, or in a cream for your skin. For bladder cancer, they might place it directly into your bladder. You may have treatment every day, week, or month. Some immunotherapies are given in cycles. It depends on your type of cancer, how advanced it is, the type of immunotherapy you get, and how well it is working.

You may have side effects. The most common side effects are skin reactions at the needle site, if you get it by IV. Other side effects may include flu-like symptoms, or rarely, severe reactions.

NIH: National Cancer Institute

While you are sleeping, you are unconscious, but your brain and body functions are still active. Sleep is a complex biological process that helps you process new information, stay healthy, and feel rested.

During sleep, your brain cycles through five stages: stage 1, 2, 3, 4, and rapid eye movement (REM) sleep. Different things happen during each stage. For example, you have a different pattern of brain waves during each one. Your breathing, heart, and temperature may be slower or faster in some stages. Certain phases of sleep help you :

• Feel rested and energetic the next day
• Learn information, get insight, and form memories
• Give your heart and vascular system a rest
• Release more growth hormone, which helps children grow. It also boosts muscle mass and the repair of cells and tissues in children and adults.
• Release sex hormones, which contributes to puberty and fertility
• Keep from getting sick or help you get better when you are sick, by creating more cytokines (hormones that help the immune system fight various infections)

You need all of the stages to get a healthy sleep.

The amount of sleep you need depends on several factors, including your age, lifestyle, health, and whether you have been getting enough sleep recently. The general recommendations for sleep are:

• Newborns: 16-18 hours a day
• Preschool-aged children: 11-12 hours a day
• School-aged children: At least 10 hours a day
• Teens: 9-10 hours a day
• Adults (including older adults): 7-8 hours a day

During puberty, teenagers' biological clocks shift, and they are more likely to go to bed later than younger children and adults, and they tend to want to sleep later in the morning. This delayed sleep-wake rhythm conflicts with the early-morning start times of many high schools and helps explain why most teenagers do not get enough sleep.

Some people think that adults need less sleep as they age. But there is no evidence to show that older adults can get by with less sleep than people who are younger. As people age, however, they often get less sleep or they tend to spend less time in the deep, restful stage of sleep. Older adults are also more easily awakened.

And it's not just the number of hours of sleep you get that matters. The quality of the sleep you get is also important. People whose sleep is frequently interrupted or cut short might not get enough of certain stages of sleep.

If you are wondering whether you are getting enough sleep, including quality sleep, ask yourself:

• Do you have trouble getting up in the morning?
• Do you have trouble focusing during the day?
• Do you doze off during the day?

If you answered yes to these three questions, you should work on improving your sleep.

Sleep is important for overall health. When you don't get enough sleep (sleep deprivation), it does more than just make you feel tired. It can affect your performance, including your ability to think clearly, react quickly, and form memories. This may cause you to make bad decisions and take more risks. People with sleep deprivation are more likely to get into accidents.

Sleep deprivation can also affect your mood, leading to:

• Irritability
• Problems with relationships, especially for children and teenagers
• Depression
• Anxiety

It can also affect your physical health. Research shows that not getting enough sleep, or getting poor-quality sleep, increases your risk of:

• High blood pressure
• Heart disease
• Stroke
• Kidney disease
• Obesity
• Type 2 diabetes

Not getting enough sleep can also mean that you don't get enough of the hormones that help children grow and help adults and children build muscle mass, fight infections, and repair cells.

Sleep deprivation magnifies the effect of alcohol. A tired person who drinks too much alcohol will be more impaired than a well-rested person.

You can take steps to improve your sleep habits. First, make sure that you allow yourself enough time to sleep. With enough sleep each night, you may find that you're happier and more productive during the day.

To improve your sleep habits, it also may help to:

• Go to bed and wake up at the same time every day
• Avoid caffeine, especially in the afternoon and evening
• Avoid nicotine
• Exercise regularly, but don't exercise too late in the day
• Avoid alcoholic drinks before bed
• Avoid large meals and beverages late at night
• Don't take a nap after 3 p.m.
• Relax before bed, for example by taking a bath, reading or listening to relaxing music
• Keep the temperature in your bedroom cool
• Get rid of distractions such as noises, bright lights, and a TV or computer in the bedroom. Also, don't be tempted to go on your phone or tablet just before bed.
• Get enough sunlight exposure during the day
• Don't lie in bed awake; if you can't sleep for 20 minutes, get up and do something relaxing
• See a doctor if you have continued trouble sleeping. You may have a sleep disorder, such as insomnia or sleep apnea. In some cases, your doctor may suggest trying over-the-counter or prescription sleep aid. In other cases, your doctor may want you to do a sleep study, to help diagnose the problem.

If you are a shift worker, it can be even harder to get a good sleep. You may also want to:

• Take naps and increase the amount of time available for sleep
• Keep the lights bright at work
• Limit shift changes so your body clock can adjust
• Limit caffeine use to the first part of your shift
• Remove sound and light distractions in your bedroom during daytime sleep (for example, use light-blocking curtains)

Anatomy is the science that studies the structure of the body. On this page, you'll find links to descriptions and pictures of the human body's parts and organ systems from head to toe.

Clinical trials are research studies that test how well new medical approaches work in people. Each study answers scientific questions and tries to find better ways to prevent, screen for, diagnose, or treat a disease. Clinical trials may also compare a new treatment to a treatment that is already available.

Every clinical trial has a protocol, or action plan, for conducting the trial. The plan describes what will be done in the study, how it will be conducted, and why each part of the study is necessary. Each study has its own rules about who can take part. Some studies need volunteers with a certain disease. Some need healthy people. Others want just men or just women.

An Institutional Review Board (IRB) reviews, monitors, and approves many clinical trials. It is an independent committee of physicians, statisticians, and members of the community. Its role is to:

• Make sure that the study is ethical
• Protect the rights and welfare of the participants
• Make sure that the risks are reasonable when compared to the potential benefits

In the United States, a clinical trial must have an IRB if it is studying a drug, biological product, or medical device that the Food and Drug Administration (FDA) regulates, or it is funded or carried out by the federal government.

NIH: National Institutes of Health

Depression is a serious medical illness. It's more than just a feeling of being sad or "blue" for a few days. If you are one of the more than 19 million teens and adults in the United States who have depression, the feelings do not go away. They persist and interfere with your everyday life. Symptoms can include:

• Feeling sad or "empty"
• Loss of interest in favorite activities
• Overeating, or not wanting to eat at all
• Not being able to sleep, or sleeping too much
• Feeling very tired
• Feeling hopeless, irritable, anxious, or guilty
• Aches or pains, headaches, cramps, or digestive problems
• Thoughts of death or suicide

Depression is a disorder of the brain. There are a variety of causes, including genetic, biological, environmental, and psychological factors. Depression can happen at any age, but it often begins in teens and young adults. It is much more common in women. Women can also get postpartum depression after the birth of a baby. Some people get seasonal affective disorder in the winter. Depression is one part of bipolar disorder.

There are effective treatments for depression, including antidepressants, talk therapy, or both.

NIH: National Institute of Mental Health

Eating disorders are serious mental health disorders. They involve severe problems with your thoughts about food and your eating behaviors. You may eat much less or much more than you need.

Eating disorders are medical conditions; they are not a lifestyle choice. They affect your body's ability to get proper nutrition. This can lead to health issues, such as heart and kidney problems, or sometimes even death. But there are treatments that can help.

Common types of eating disorders include:

• Binge-eating, which is out-of-control eating. People with binge-eating disorder keep eating even after they are full. They often eat until they feel very uncomfortable. Afterward, they usually have feelings of guilt, shame, and distress. Eating too much too often can lead to weight gain and obesity. Binge-eating disorder is the most common eating disorder in the U.S.
• Bulimia nervosa. People with bulimia nervosa also have periods of binge-eating. But afterwards, they purge, by making themselves throw up or using laxatives. They may also over-exercise or fast. People with bulimia nervosa may be slightly underweight, normal weight, or overweight.
• Anorexia nervosa. People with anorexia nervosa avoid food, severely restrict food, or eat very small quantities of only certain foods. They may see themselves as overweight, even when they are dangerously underweight. Anorexia nervosa is the least common of the three eating disorders, but it is often the most serious. It has the highest death rate of any mental disorder.

The exact cause of eating disorders is unknown. Researchers believe that eating disorders are caused by a complex interaction of factors. These include genetic, biological, behavioral, psychological, and social factors.

Anyone can develop an eating disorder, but they are more common in women. Eating disorders frequently appear during the teen years or young adulthood. But people can also develop them during childhood or later in life.

The symptoms of eating disorders vary, depending on the disorder:

The symptoms of binge-eating include:

• Eating unusually large amounts of food in a specific amount of time, such as a 2-hour period
• Eating even when you're full or not hungry
• Eating fast during binge episodes
• Eating until you're uncomfortably full
• Eating alone or in secret to avoid embarrassment
• Feeling distressed, ashamed, or guilty about your eating
• Frequently dieting, possibly without weight loss

The symptoms of bulimia nervosa include the same symptoms as binge-eating, plus trying to get rid of the food or weight after binging by:

• Purging, making yourself throw up or using laxatives or enemas to speed up the movement of food through your body
• Doing intensive and excessive exercise
• Fasting

Over time, bulimia nervosa can cause health problems such as:

• Chronically inflamed and sore throat
• Swollen salivary glands in the neck and jaw area
• Worn tooth enamel and increasingly sensitive and decaying teeth. This is caused by the exposure to stomach acid every time you throw up.
• GERD (acid reflux) and other gastrointestinal problems
• Severe dehydration from purging
• Electrolyte imbalance, which could be too low or too high levels of sodium, calcium, potassium and other minerals. This can lead to a stroke or heart attack.

The symptoms of anorexia nervosa include:

• Eating very little, to the point of starving yourself
• Intensive and excessive exercise
• Extreme thinness
• Intense fear of gaining weight
• Distorted body image - seeing yourself as overweight even when you are severely underweight

Over time, anorexia nervosa can cause health problems such as:

• Thinning of the bones (osteopenia or osteoporosis)
• Mild anemia
• Muscle wasting and weakness
• Thin, brittle hair and nails
• Dry, blotchy, or yellowish skin
• Growth of fine hair all over the body
• Severe constipation
• Low blood pressure
• Slowed breathing and pulse
• Feeling cold all the time because of a drop in internal body temperature
• Feeling faint, dizzy, or weak
• Feeling tired all the time
• Infertility
• Damage to the structure and function of the heart
• Brain damage
• Multiorgan failure

Anorexia nervosa can be fatal. Some people with this disorder die of complications from starvation, and others die of suicide.

Some people with eating disorders may also have other mental disorders (such as depression or anxiety) or problems with substance use.

Because eating disorders can be so serious, it is important to seek help if you or a loved one thinks that you might have a problem. Your health care provider may use many tools to make a diagnosis:

• A medical history, which includes asking about your symptoms. It is important to be honest about your eating and exercise behaviors so your provider can help you.
• A physical exam
• Blood or urine tests to rule out other possible causes of your symptoms
• Other tests to see whether you have any other health problems caused by the eating disorder. These can include kidney function tests and an electrocardiogram (EKG or ECG).

Treatment plans for eating disorders are tailored to individual needs. You will likely have a team of providers helping you, including doctors, nutritionists, nurses, and therapists. The treatments may include:

• Individual, group, and/or family psychotherapy. Individual therapy may include cognitive behavioral approaches, which help you to identify and change negative and unhelpful thoughts. It also helps you build coping skills and change behavioral patterns.
• Medical care and monitoring, including care for the complications that eating disorders can cause
• Nutrition counseling. Doctors, nurses, and counselors will help you eat healthy to reach and maintain a healthy weight.
• Medicines, such as antidepressants, antipsychotics, or mood stabilizers, may help treat some eating disorders. The medicines can also help with the depression and anxiety symptoms that often go along with eating disorders.

Some people with serious eating disorders may need to be in a hospital or in a residential treatment program. Residential treatment programs combine housing and treatment services.

NIH: National Institute of Mental Health

Genes are the building blocks of inheritance. Passed from parent to child, they contain instructions for making proteins. If genes don't produce the right proteins or don't produce them correctly, a child can have a genetic disorder.

Gene therapy is an experimental technique that uses genes to treat or prevent disease. The most common form of gene therapy involves inserting a normal gene to replace an abnormal gene. Other approaches include:

• Swapping an abnormal gene for a normal one
• Repairing an abnormal gene
• Altering the degree to which a gene is turned on or off

Although there is much hope for gene therapy, it is still experimental.

Every day, around the clock, people who work in the health care industry provide care for millions of people, from newborns to the very ill. In fact, the health care industry is one of largest providers of jobs in the United States. Many health jobs are in hospitals. Others are in nursing homes, doctors' offices, dentists' offices, outpatient clinics and laboratories.

To work in a health occupation, you often must have special training. Some, like doctors, must have more than 4 years of college.

Bureau of Labor Statistics

Every year, lives are lost because of the spread of infections in hospitals. Health care workers can take steps to prevent the spread of infectious diseases. These steps are part of infection control.

Proper hand washing is the most effective way to prevent the spread of infections in hospitals. If you are a patient, don't be afraid to remind friends, family and health care providers to wash their hands before getting close to you.

Other steps health care workers can take include:

• Covering coughs and sneezes
• Staying up to date with vaccinations
• Using gloves, masks and protective clothing
• Making tissues and hand cleaners available
• Following hospital guidelines when dealing with blood or contaminated items