Stem Cells

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair system for the body. There are two main types of stem cells: embryonic stem cells and adult stem cells.

Stem cells are different from other cells in the body in three ways:

• They can divide and renew themselves over a long time
• They are unspecialized, so they cannot do specific functions in the body
• They have the potential to become specialized cells, such as muscle cells, blood cells, and brain cells

Doctors and scientists are excited about stem cells because they could help in many different areas of health and medical research. Studying stem cells may help explain how serious conditions such as birth defects and cancer come about. Stem cells may one day be used to make cells and tissues for therapy of many diseases. Examples include Parkinson's disease, Alzheimer's disease, spinal cord injury, heart disease, diabetes, and arthritis.

NIH: National Institutes of Health

Stress

What is stress?

Stress is how your brain and body respond to a challenge or demand. When you are stressed, your body releases certain hormones. Hormones are chemicals that travel in your bloodstream and control how different parts of your body work. The hormones that are released when you are stressed make you alert and ready to act. They can raise your blood pressure, heart rate, and blood glucose (blood sugar) levels. This response is sometimes called a "fight or flight" response.

Everyone gets stressed from time to time. There are different types of stress. It can be short-term or long-term. It can be caused by something that happens once or something that keeps happening.

Not all stress is bad. In fact, it can help you survive in a dangerous situation. For example, one kind of stress is the jolt you may feel when a car pulls out in front of you while you are driving. This jolt of hormones helps you quickly hit the brakes to avoid an accident. A little short-term stress can sometimes be helpful. For example, the stress of having a deadline for school or your job may push you to get your work done on time. Once you finish it, that stress goes away.

But stress that lasts a long time can harm your health.

Long-term stress, or chronic stress, lasts for weeks, months, or longer. As you go about your life, your body is acting as if you're being threatened.

Causes of long-term stress include:

• Routine stress from the demands of work, school, family needs, money problems, and other daily pressures that don't stop.
• Stress from sudden, difficult changes in your life, such as divorce, illness, losing your job, or other unhappy life events that often have a long impact.
• Traumatic stress, which may happen when you're in danger of serious harm or death. Examples include being in a bad accident, a war, a flood, earthquake, or other frightening event. This type of stress can cause a long-lasting problem called post-traumatic stress disorder (PTSD).

People respond to stress in different ways. If you're stressed for a long time you may notice that you are:

• Getting sick more often than usual because stress weakens your body's ability to fight germs
• Having stomach problems or trouble digesting food
• Having trouble sleeping
• Having headaches
• Feeling sad, angry, or easily upset

When stress keeps going, your body acts as if you're always in danger. That's a lot of strain that may play a part in developing serious health problems, including:

• Depression
• Anxiety
• Heart disease
• High blood pressure
• Diabetes

It's possible to get used to the symptoms of stress and not even realize there's a problem. So when there's a lot of stress in your life, it's important to pay attention to how it affects you so you can do something about it.

Simple things that improve your mental health may be helpful in managing long-term stress, such as:

• Get regular exercise. A 30-minute daily walk can help you feel better and help keep your immune system strong, so you don't get sick.
• Try relaxing activities. You could look for an app or wellness program that uses breathing, meditation, or muscle relaxation exercises.
• Get enough sleep every night.
• Avoid too much caffeine.
• Decide what you need to do now and what can wait. And focus on what you got done each day, not on what you weren't able to do.
• Ask your family or friends for support.

Get help if you're having severe symptoms for 2 weeks or more, including:

• Trouble sleeping
• Changes in your eating that cause unwanted changes in your weight
• Troubles getting out of bed because of your mood
• Difficulty focusing your thoughts
• Losing interest in things you usually enjoy
• Not being able to do your usual daily activities

Always get help right away if stress is causing you to:

• Have thoughts of suicide
• Feel you can't cope
• Use drugs or alcohol more often than usual

Your health care provider may refer you to a mental health professional such as a psychologist or social worker.

NIH: National Institute of Mental Health

Sudden Cardiac Arrest

What is sudden cardiac arrest (SCA)?

Sudden cardiac arrest (SCA) is a condition in which the heart suddenly stops beating. When that happens, blood stops flowing to the brain and other vital organs. If it is not treated, SCA usually causes death within minutes. But quick treatment with a defibrillator may be lifesaving.

A heart attack is different from an SCA. A heart attack happens when blood flow to the heart is blocked. During a heart attack, the heart usually doesn't suddenly stop beating. With an SCA, the heart stops beating.

Sometimes an SCA can happen after or during recovery from a heart attack.

Your heart has an electrical system that controls the rate and rhythm of your heartbeat. An SCA can happen when the heart's electrical system is not working right and causes irregular heartbeats. Irregular heartbeats are called arrhythmias. There are different types. They may cause the heart to beat too fast, too slow, or with an irregular rhythm. Some can cause the heart to stop pumping blood to the body; this is the type that causes SCA.

Certain diseases and conditions can cause the electrical problems that lead to SCA. They include:

• Ventricular fibrillation, a type of arrhythmia where the ventricles (the heart's lower chambers) don't beat normally. Instead, they beat very fast and very irregularly. They can't pump blood to the body. This causes most SCAs.
• Coronary artery disease (CAD), also called ischemic heart disease. CAD happens when the arteries of the heart cannot deliver enough oxygen-rich blood to the heart. It is often caused by the buildup of plaque, a waxy substance, inside the lining of larger coronary arteries. The plaque blocks some or all of the blood flow to the heart.
• Some types of physical stress can cause your heart's electrical system to fail, such as
  • Intense physical activity in which your body releases the hormone adrenaline. This hormone can trigger SCA in people who have heart problems.
  • Very low blood levels of potassium or magnesium. These minerals play an important role in your heart's electrical system.
  • Major blood loss
  • Severe lack of oxygen
• Certain inherited disorders which can cause arrhythmias or problems with the structure of your heart
• Structural changes in the heart, such as an enlarged heart due to high blood pressure or advanced heart disease. Heart infections can also cause changes to the structure of the heart.

You are at higher risk for SCA if you:

• Have coronary artery disease (CAD). Most people with SCA have CAD. But CAD usually doesn't cause symptoms, so they may not know that they have it.
• Are older; your risk increases with age
• Are a man; it is more common in men than women
• Are Black or African American, especially if you have other conditions such as diabetes, high blood pressure, heart failure, or chronic kidney disease
• Have a personal history of heartbeats that aren't regular (arrhythmia)
• Have a personal or family history of SCA or inherited disorders that can cause arrhythmia
• Have a problem with drug or alcohol use
• Have had a heart attack
• Have heart failure

Usually, the first sign of SCA is loss of consciousness (fainting). This happens when the heart stops beating.

Some people may have a racing heartbeat or feel dizzy or light-headed just before they faint. And sometimes people have chest pain, shortness of breath, nausea, or vomiting in the hour before they have an SCA.

SCA happens without warning and requires emergency treatment. Health care providers rarely diagnose SCA with medical tests as it's happening. Instead, it is usually diagnosed after it happens. Providers do this by ruling out other causes of a person's sudden collapse.

If you are at high risk for SCA, your provider may refer you to a cardiologist, a doctor who specializes in heart diseases. The cardiologist may ask you to get various heart health tests to see how well you heart is working. He or she will work with you to decide whether you need treatment to prevent SCA.

SCA is an emergency. A person having SCA needs to be treated with a defibrillator right away. A defibrillator is a device sends an electric shock to the heart. The electric shock can restore a normal rhythm to a heart that's stopped beating. To work well, it needs to be done within minutes of the SCA.

Most police officers, emergency medical technicians, and other first responders are trained and equipped to use a defibrillator. Call 9-1-1 right away if someone has signs or symptoms of SCA. The sooner you call for help, the sooner lifesaving treatment can begin.

Many public places such as schools, businesses, and airports have automated external defibrillators (AEDs). AEDs are special defibrillators that untrained people can use if they think that someone has had SCA. AEDS are programmed to give an electric shock if they detect a dangerous arrhythmia. This prevents giving a shock to someone who may have fainted but isn't having SCA.

If you see someone who you think has had SCA, you should give cardiopulmonary resuscitation (CPR) until defibrillation can be done.

People who are at risk for SCA may want to consider having an AED at home. Ask your cardiologist to help you decide whether having an AED in your home might help you.

If you survive SCA, you'll likely be admitted to a hospital for ongoing care and treatment. In the hospital, your medical team will closely watch your heart. They may give you medicines to try to reduce the risk of another SCA.

They will also try to find out what caused your SCA. If you're diagnosed with coronary artery disease, you may have an angioplasty or coronary artery bypass surgery. These procedures help restore blood flow through narrowed or blocked coronary arteries.

Often, people who have had SCA get a device called an implantable cardioverter defibrillator (ICD). This small device is surgically placed under the skin in your chest or abdomen. An ICD uses electric pulses or shocks to help control dangerous arrhythmias.

You may be able to lower your risk of SCA by following a heart-healthy lifestyle. If you have coronary artery disease or another heart disease, treating that disease can also lower your risk of SCA. If you have had an SCA, getting an implantable cardioverter defibrillator (ICD) can lower your chance of having another SCA.

NIH: National Heart, Lung, and Blood Institute

Surgery

There are many reasons to have surgery. Some operations can relieve or prevent pain. Others can reduce a symptom of a problem or improve some body function. Some surgeries are done to find a problem. For example, a surgeon may do a biopsy, which involves removing a piece of tissue to examine under a microscope. Some surgeries, like heart surgery, can save your life.

Some operations that once needed large incisions (cuts in the body) can now be done using much smaller cuts. This is called laparoscopic surgery. Surgeons insert a thin tube with a camera to see, and use small tools to do the surgery.

After surgery there can be a risk of complications, including infection, too much bleeding, reaction to anesthesia, or accidental injury. There is almost always some pain with surgery.

Agency for Healthcare Research and Quality

Teen Depression

What is depression in teens?

Depression in teens (ages 13-17) is a serious medical illness. It's more than just a feeling of being sad or "blue" for a few days. It is an intense feeling of sadness, hopelessness, and anger or frustration that lasts much longer. These feelings make it hard for you to function normally and do your usual activities. You may also have trouble focusing and have no motivation or energy. Depression can make you feel like it is hard to enjoy life or even get through the day.

Many factors may play a role in depression, including:

• Genetics. Depression can run in families.
• Brain biology and chemistry.
• Hormones. Hormone changes can contribute to depression.
• Stressful childhood events such as trauma, the death of a loved one, bullying, and abuse.

Depression can happen at any age, but often begins in the teens or early adulthood. Certain teens are at higher risk of depression, such as those who:

• Have other mental health conditions, such as anxiety, eating disorders, and substance use
• Have other diseases, such as diabetes, cancer, and heart disease
• Have family members with mental illness
• Have a dysfunctional family/family conflict
• Have problems with friends or other kids at school
• Have learning disabilities or attention deficit hyperactivity disorder (ADHD)
• Have had trauma in childhood
• Have low self-esteem, a pessimistic outlook, or poor coping skills
• Are members of the LGBTQIA+ community, especially when their families are not supportive

If you have depression, you have one or more of these symptoms most of the time:

• Sadness
• Feeling of emptiness
• Hopelessness
• Being angry, irritable, or frustrated, even at minor things

You also may also have other symptoms, such as:

• No longer caring about things you used to enjoy
• Changes in weight, such as losing weight when you are not dieting or gaining weight from eating too much
• Changes in sleep, such as having trouble falling asleep or staying asleep, or sleeping much more than usual
• Feeling restless or having trouble sitting still
• Feeling very tired or not having energy
• Feeling worthless or very guilty
• Having trouble concentrating, remembering information, or making decisions
• Thinking about dying or suicide

If you think you might be depressed, tell someone that you trust, such as your:

• Parents or guardian
• Teacher or counselor
• Doctor

The next step is to see your doctor for a checkup. Your doctor can first make sure that you do not have another health problem that is causing your depression. To do this, you may have a physical exam and lab tests.

If you don't have another health problem, you will get a psychological evaluation. Your doctor may do it, or you may be referred to a mental health professional to get one. You may be asked about things such as:

• Your thoughts and feelings
• How you are doing at school
• Any changes in your eating, sleeping, or energy level
• Whether you are suicidal
• Whether you use alcohol or drugs

Effective treatments for depression in teens include talk therapy, or a combination of talk therapy and medicines:

Talk therapy

Talk therapy, also called psychotherapy or counseling, can help you understand and manage your moods and feelings. It involves going to see a therapist, such as a psychiatrist, a psychologist, a social worker, or counselor. You can talk out your emotions to someone who understands and supports you. You can also learn how to stop thinking negatively and start to look at the positives in life. This will help you build confidence and feel better about yourself.

There are many different types of talk therapy. Certain types have been shown to help teens deal with depression, including:

• Cognitive behavioral therapy (CBT), which helps you to identify and change negative and unhelpful thoughts. It also helps you build coping skills and change behavioral patterns.
• Interpersonal therapy (IPT), which focuses on improving your relationships. It helps you understand and work through troubled relationships that may contribute to your depression. IPT may help you change behaviors that are causing problems. You also explore major issues that may add to your depression, such as grief or life changes.

Medicines

In some cases, your doctor will suggest medicines along with talk therapy. There are a few antidepressants that have been widely studied and proven to help teens. If you are taking medicine for depression, it is important to see your doctor regularly.

It is also important to know that it will take some time for you to get relief from antidepressants:

• It can take 3 to 4 weeks until an antidepressant takes effect
• You may have to try more than one antidepressant to find one that works for you
• It can also take some time to find the right dose of an antidepressant

In some cases, teenagers may have an increase in suicidal thoughts or behavior when taking antidepressants. This risk is higher in the first few weeks after starting the medicine and when the dose is changed. Make sure to tell your parents or guardian if you start feeling worse or have thoughts of hurting yourself.

You should not stop taking the antidepressants on your own. You need to work with your doctor to slowly and safely decrease the dose before you stop.

Programs for severe depression

Some teens who have severe depression or are at risk of hurting themselves may need more intensive treatment. They may go into a psychiatric hospital or do a day program. Both offer counseling, group discussions, and activities with mental health professionals and other patients. Day programs may be full-day or half-day, and they often last for several weeks.