New advance against a form of heart failure prevalent in men

 Unlike women, who have two X chromosomes, men have an X and a Y. For a long time, the genes found on the Y chromosome were not thought to play important roles in disease. Sex hormones, scientists thought, explained the differences in certain diseases in men and women. But Walsh's groundbreaking work has helped change that perception. It also suggested an explanation for why heart failure is more common in men than women. (Cardiovascular disease, which includes heart failure, is the leading cause of death worldwide.)

Y chromosome loss occurs in only a small percentage of affected men's cells. This results in what is called "mosaicism," where genetically different cells occur within one individual. Researchers aren't entirely sure why this partial Y chromosome loss occurs, but predominantly it strikes elderly men and men who smoke compared to those who don't.

To better understand the effects of Y chromosome loss, Walsh and his team examined genes found on the Y chromosome to determine which might be important to heart scarring. One gene they looked at, Uty, helps control the operating instructions for immune cells called macrophages and monocytes, the scientists determined. When the Uty gene was disrupted, either individually or through Y chromosome loss, that triggered changes in the immune cells in lab mice. Suddenly, the macrophages were much more "pro-fibrotic," or prone to scarring. This accelerated heart failure as well, the scientists found.

"The identification of a single gene on the Y chromosome provides information about a new druggable target to treat fibrotic diseases," said Walsh, of UVA's Division of Cardiovascular Medicine and Robert M. Berne Cardiovascular Research Center.

Walsh and his team were able to prevent the harmful changes in the mice's macrophages by giving them a specially designed monoclonal antibody. This halted the harmful changes in the heart, suggesting the approach might, with further research, lead to a way to treat or avoid heart failure and other fibrotic diseases in men with Y chromosome loss.

"Currently, we are working with our clinician colleagues in the Division of Cardiovascular Medicine at UVA to assess whether loss of the Y chromosome in men is associated with greater scarring in the heart," Walsh said. "This research will provide new avenues for understanding the causes of heart disease."

Based on their findings, Walsh and his team believe that a small group of genes found on the Y chromosome may have big effects on a wide array of diseases. Their new work identifies mechanisms that may lead to this, and they are hopeful that further research will provide a much better understanding of unknown causes of sickness and death in men.

"This research further documents the utility of studying the genetics of mutations that are acquired after conception and accumulate throughout life," Walsh said. "These mutations appear to be as important to health and lifespan as the mutations that are inherited from one's parents. The study of these age-acquired mutations represents a new field of human genetics."

sources-science daily

What is DNA and how does it impact health?

 DNA is a biological molecule that contains the instructions an organism needs to function, develop, and reproduce. It is present in all forms of life on earth and contains each organism’s genetic code.

Virtually every cell in the body contains deoxyribonucleic acid (DNA). It is the genetic code that makes each person unique. DNA carries the instructions for the development, growth, reproduction, and functioning of all life.

Differences in the genetic code are why one person has blue eyes rather than brown, why birds only have two wings, or why giraffes have long necks. Differences or mutations in the genetic code can also lead to being susceptible to certain diseases.

Not only do nearly all cells in the body contain DNA, but the DNA in a single cell would span over 6.5 feet (ft) longTrusted Source if unraveled and stretched end-to-end.

This article will break down the basics of DNA, what it is made of, how it works, and how it impacts health.

What is DNA?

In short, DNA is a long molecule that contains each person’s unique genetic code. It holdsTrusted Source the instructions for building the proteins essential for the body’s function.

DNA instructions pass from parent to child, with roughly half of a child’s DNA originating from the father and half from the mother.

How is DNA structured?

DNA is a two-stranded molecule that appears twisted, giving it a unique shape referred toTrusted Source as the double helix.

Each of the two strands is a long sequence of nucleotides. These are the individual units of DNA and they are made of:

• a phosphate molecule
• a sugar molecule called deoxyribose, containing five carbons
• a nitrogen-containing region

There are four types of nitrogen-containing regions called bases, includingTrusted Source:

• adenine (A)
• cytosine (C)
• guanine (G)
• thymine (T)

The order of these four bases forms the genetic code, which is the instructions for life.

The bases of the two strands of DNA are stuck together to create a ladder-like shape. Within the ladder, A sticks to T, and G sticks to C to create the “rungs.” The length of the ladder forms through the sugar and phosphate groups.

What is a gene?

Each length of DNA that codes for a specific protein is called a gene. For instance, one gene codes for the protein insulin, the hormone that helps control levels of sugar in the blood. Humans have around 30,000 genesTrusted Source, although estimates vary.

It’s believed that only about 1%Trusted Source of DNA is made up of protein-coding genes. Scientists know less about the function of the remaining 99% of DNA but believe them to be involved in regulating transcription and translation.

Chromosome 1 is the largest and contains around 2,800 genesTrusted Source. The smallest is chromosome 22 with around 750 genes.

How does DNA work?

Most DNA lives in the nuclei of cells and some exist in mitochondria, which are the powerhouses of the cells.

Because humans have so much DNA and the nuclei are so small, DNA needs to be packaged incredibly neatly.

Strands of DNA loop, coil, and wrap around proteins calledTrusted Source histones. In this coiled state, it is DNA is called chromatin.

Chromatin condenses further through a supercoiling process and packages into structures called chromosomes. These chromosomes form the familiar “X” shape.

Each chromosome contains one DNA molecule. Humans have 23 pairs of chromosomes or 46 chromosomes in total. Other species have different numbers. For example, fruit flies have 8 chromosomesTrusted Source, while pigeons have 80 chromosomesTrusted Source.

Protein creation

For genes to create a protein, there are two main steps, includingTrusted Source:

• Transcription: The DNA code duplicates into messenger RNA (mRNA). RNA is a copy of DNA, but it is normally single-stranded. Another difference is that RNA does not contain the base thymine (T). In RNA, uracil (U) replaces thymine (T).
• Translation: The mRNA translates into amino acids by transfer RNA (tRNA).

mRNA provides information on a particular amino acid via three-letter sections calledTrusted Source codons. Each codon codes for a specific amino acid or building block of a protein. For instance, the codon GUG codes for the amino acid valine.

There are 20 possible amino acids.

Telomeres

Telomeres are regions of repeated nucleotides at the end of chromosomes.

They protectTrusted Source the ends of the chromosome from being damaged or fusing with other chromosomes.

Scientists liken them to the plastic tips on shoelaces that stop them from becoming frayed.

As a person gets older, this protective region steadily becomes smaller. Each time a cell divides and DNA is replicated, the telomere becomes shorter.

How does DNA affect health?

In all people, DNA degradesTrusted Source over time, causing people to age.

Sometimes, however, a person’s DNA sequence may change randomly. This is called a mutation. Certain mutations in a person’s genetic code can lead them to develop a variety of diseases or conditions.

Alternatively, a person can inherit a gene that may cause problems with their health. Environmental factors can influence how these mutated genes manifest.

Damage to the structure of DNA can occur in various ways. This includes when:

• the bases connect in the wrong order after replication
• a base pair is missing
• there is an extra base pair
• there is a malfunction in DNA replication or recombination
• there is exposure to environmental factors such as radiation or heavy metals
• there is a mutation in the process of repairing damaged DNA.
• there is a change in the number or structure of chromosomes

Diseases or health conditions can result from damage in only one gene, such as cystic fibrosis, or damage in several parts of a person’s DNA, such as cancer. Other examples include:

• Down’s syndrome
• autoimmune conditions
• chronic inflammatory conditions
• neurodegenerative diseases like Huntington’s disease

Frequently asked questions

Here are a few common questions about DNA.

Who discovered DNA?

The discovery of DNA is credited to Swiss scientist Friedrich Miescher, who first isolatedTrusted Source DNA from human pus cells in the late 1860s.

What are the different types of DNA?

There are many types of DNA, each of which varies depending on its specific structure. The most common is B-DNA, but some other types found in the genome include A-DNA, H-DNA, and Z-DNA.

What is DNA replication?

DNA replication is a process that occursTrusted Source when DNA in the cells copies itself. This helps ensure that each new cell has its own complete genome during cell division.

Can genetic diseases be cured?

Doctors can only treat the symptoms of conditions caused by a genetic mutation. However, researchers are continuously working to develop gene therapy types that may help stop a disease from progressing. The U.S. Food and Drug Administration (FDA) has approved some gene therapy drugs, while others are undergoing clinical trials.

Summary

DNA is a molecule found in most cells holding each person’s unique genetic code. It is responsible for coding proteins, which are essential to the growth and development of cells.

Chromosomes are tightly coiled strands of DNA. Genes are sections of DNA that code individual proteins. DNA also carries important genetic information necessary for the survival and function of all life forms on earth.

Put another way, DNA is the master plan for life on earth and gives all living organisms their unique genetic code. When something in this plan malfunctions, diseases and health problems can occur.

Source - Medical News Today

What to know about soft tissue injuries

 Soft tissue injuries typically describe damage to muscles, tendons, and ligaments. They may lead to pain, swelling, and restricted mobility and can occur for many reasons.

Some potential causes include athletes repeatedly overusing their soft tissues and physical trauma.

This article explores the types, symptoms, causes, and diagnosis of soft tissue injuries and how to treat and prevent them.

What are soft tissue injuries?

Soft tissue describes any tissue in the body that is not bone. However, when discussing soft tissue injuries, people are mainly referring to:

• Muscles: These are responsible for creating force and movementTrusted Source by contracting and expanding. A range of tough fibers make up muscles.
• Tendons: These consist of tough tissue that connects muscles to bones. They transmit strengthTrusted Source from the muscles to the bones and joints.
• Ligaments: These connect bones to other bones, providing stability.

Types of soft tissue injuries

Soft tissue injuries cover a range of conditions that damage the muscles, tendons, ligaments, and other connective tissues. According to the American Academy of Orthopaedic Surgeons (AAOS), common types include:

• Sprains: These involve the stretching or tearing of ligaments. These commonly occur in the wrists, ankles, and knees.
• Strains: These refer to muscle or tendon damage, often occurring to the hamstring in the back of the leg.
• Contusions: These are bruises resulting from blunt force trauma that squashes muscle fibers underneath the skin without breaking the skin barrier. A bruise’s color forms from blood pooling around the affected area.
• Tendinitis: This is a continuous irritation or inflammation in a tendon that occurs due to overuse. Over time, tiny stresses and tears cause the tendon to flare up.
• Bursitis: The bursae are small sacs between soft tissue and bones that cushion the shoulder, elbow, knee, hip, and heel. Similarly to tendinitis, small stresses over time can cause inflammation and swelling in the bursae.

These injuries often result from sudden twists, impacts, or overuse of a particular muscle or joint.

Symptoms

The different soft tissue injuries often present distinct symptoms, although they usually involve some combination of the following:

• pain
• swelling
• bruising
• limited range of motion
• weakness

However, some injuries may cause other symptoms specific to the injury. The table below provides some examples.

Soft tissue injury	Common symptoms
Sprain	Swelling, bruising, pain, and inflammation
Strain	Pain, muscle spasms, swelling, and inflammation
Contusion	Pain and skin discoloration
Tendinitis	Swelling and pain that worsens during activity
Bursitis	Swelling and pain

Causes

Soft tissue injuries are common in sports and exercise. However, they can also occur during everyday activities, accidents, and workplace duties. Causes often involve the following:

• Trauma: Sudden impact or forceful movements can lead to a soft tissue injury. This might occur due to a fall, a slip, or a sharp change in direction.
• Overuse: Repetitive movements or excessive strain on a particular muscle or joint. Overuse injuries are common in people who play sports. Inadequate warmup before physical activity can increase the risk of sporting injuries.
• Overloading: A sudden increase in exercise intensity can lead to a soft tissue injury, according to the United Kingdom’s National Health Service (NHS). This may include lifting much heavier weights without a gradual buildup or running a greater distance with no training.

Diagnosis

A healthcare professional may use a combination of clinical evaluation and imaging tests to diagnose a soft tissue injury. The clinical assessment often involves a doctor evaluating symptoms, taking a medical history, and performing a physical examination.

For people with a mild injury, imaging usually is not necessary for diagnosis. However, doctors sometimes may use imaging tests, such as an MRI and X-rays, to create images of soft tissue damage, assess the extent of the injury, and rule out other potential injuries, including fractures.

Treatment

Treatment for soft tissue injuries depends on several factors, including:

• the severity
• the type of injury
• the particular joint, muscle, or limb affected

People can often self-treat mild soft tissue injuries without seeing a doctor. People with severe, sudden, or continuous pain should speak with a healthcare professional. Likewise, if the pain does not resolve over 2 weeks or it continues to worsen, a person may benefit from a medical opinion.

The main approach to treating an acute injury due to a sudden trauma usually involves the rest, ice, compression, and elevation (RICE) method.

However, ongoing injuries, such as tendinopathy, may require a different approach with more input from a clinician.

• Medications: A doctor can recommend appropriate over-the-counter (OTC) pain relievers and nonsteroidal anti-inflammatory drugs (NSAIDs). However, according to the NHS, NSAIDs might actually slow the healing process, if a person takes them too early. Therefore, a person should speak with a doctor before taking any medications.
• Physical therapy: Targeted exercises focusing on load weight, speed of motion, and how often a person repeats movements can helpTrusted Source improve strength, flexibility, and mobility, according to older 2015 research.
• Bracing or splinting: Stopping the injured area from moving can help preventTrusted Source further damage.

Torn muscles, tendons, or ligaments may need surgery depending on how much of the tendon has torn and how severe it is.

People should speak with a doctor about which treatments may work best for them.

Prevention

Preventing soft tissue injuries usually involves specific training techniques and conditioning the body to respond better to physical effort.

The following strategies from the AAOS may help prevent injury:

• warming up before and cooling down after exercising
• focusing on maintaining the right technique during workouts
• drinking plenty of water
• scheduling rest days between intense exercises
• practicing stretching and not stretching to the point of pain
• gradually increasing the intensity and duration of exercise
• replacing worn-out training shoes and wearing appropriate exercise clothing

People should pay attention to any pain or discomfort they experience and seek medical attention if needed. It is best to avoid “working through” twinges or pain, as this can risk further injury.

Summary

Soft tissue injuries include sprains, strains, and contusions of any tissue that is not bone. This usually refers to tendon, ligament, and muscle injuries. They often result from acute trauma or injury, but also include overuse injuries, such as tendonitis and bursitis.

Symptoms may include pain, swelling, stiffness, weakness, and a reduced range of motion. A person may not need to seek medical attention for mild cases, which they can treat at home with rest, ice, compression, and elevation.

More severe or persistent soft tissue injuries may need physical therapy, medications, and bracing or splinting. A torn ligament or tendon may need surgical repair. A person should speak with a doctor to find out which treatment is most appropriate for them.

People can help prevent soft tissue injuries during exercise by warming up and cooling down, taking time to rest, and maintaining proper technique.

Source - Medical News Today

What to know about myotonic dystrophy

 Myotonic dystrophy is a condition that causes thinned muscles, decreased muscle tone, and muscle weakness. Over time, a person may lose their strength and have issues relaxing their muscles. The severity of symptoms and speed of progression varies.

There are two types of myotonic dystrophy: type 1 (DM1) and type 2 (DM2). It is an inherited condition, and someone only needs one copy of the atypical gene relating to the condition to develop symptoms.

Although there is no cure for myotonic dystrophy, a person may receive treatment for complications such as cataracts and diabetes.

Read on to learn more about myotonic dystrophy and its causes. This article also looks at symptoms, how doctors diagnose the condition, and more.

What are the types of myotonic dystrophy?

There are two types of myotonic dystrophy: DM1 and DM2, and different genetic mutations cause each type. These mutations affect the muscle structure, leading to weakness and altered muscle tone.

DM1

DM1, or Steinart disease, ranges in severity. There are fourTrusted Source different subtypes:

• congenital myotonic dystrophy, which can be present from birth
• mild myotonic dystrophy, which typically begins after age 40 years
• classic myotonic dystrophy, which typically begins when a person is in their 10s–30s
• childhood myotonic dystrophy, which typically begins from around the age of 10 years

Typically, DM1 affects muscles further away from the center of the body, such as the hands and feet.

DM2

DM2 typically affects muscles that are closer to the center of the body, such as the neck and elbows. It typically begins in adulthood, with a median age of 48 years.

What causes myotonic dystrophy?

A genetic mutation causes myotonic dystrophy. However, DM1 and DM2 are not due to the same genetic mutation. With DM1, the mutation affects the DMPK gene, while with DM2, the mutation is on the CNBP gene, or ZNF9 gene.

As myotonic dystrophy is autosomal dominant, a person only needs to inherit one mutated gene to develop symptoms. This means that if a biological parent has DM1 or DM2, there is a 50% risk their child will also inherit the condition.

What are the symptoms of myotonic dystrophy?

The symptoms of myotonic dystrophy in DM1 and DM2 generally include:

• weakness in the neck, finger fingers, and hips
• sustained muscle contraction
• fatigue
• cardiac problems
• thyroid issues
• hormone dysfunction
• hearing impairments
• gastrointestinal issues
• problems with the immune system

DM1 can also include signs of intellectual disability, though this is not typicallyTrusted Source the case with DM2.

Myotonic dystrophy can also lead to conditions such as type 2 diabetes and cataracts.

How does myotonic dystrophy progress?

DM2 has a milder progression than DM1. When a person has DM1, they may requireTrusted Source a wheelchair as the condition progresses.

Progression is relatively slow for both types, but more negative outcomes in DM1 are more likely due toTrusted Source:

• diabetes
• issues with blood pressure
• a need for walking support
• respiratory issues
• irregular heartbeat

A person’s doctor can provide more information about how their condition may progress.

How do doctors diagnose myotonic dystrophy?

When a person has symptoms of myotonic dystrophy, a doctor may first ask them questions about their symptoms and take a full medical history. As the condition is hereditary, they will typically also ask about their family medical history.

The doctor may then order various tests to assist with reaching an accurate diagnosis. The types of exams and tests a doctor will use includeTrusted Source:

• A physical exam: This will involve checking for muscle wasting and weakness. It will also check a person’s reflexes and muscle tone.
• An electromyography (EMG): This measures electrical activity in the muscle.
• Genetic tests: A doctor can use genetic tests to screen for any alterations in the DMPK and CNBP genes.

What are the treatments for myotonic dystrophy?

There is currently no treatmentTrusted Source for myotonic dystrophy. However, doctors can recommend treatments for specific symptoms.

Treatments may include:

• walking aids to help with mobility
• medication for heart problems
• medications to help with muscle stiffness
• respiratory therapy for breathing problems
• diet and speech therapy for swallowing problems (dysphagia)
• physical therapy for support with exercises
• occupational therapy to help with maintaining independence

How common is myotonic dystrophy?

Myotonic dystrophy affects 1 in 8,000Trusted Source people worldwide. It is the most common form of muscular dystrophy that begins in adulthood.

In the United States, the condition affects 8 in 100,000 peopleTrusted Source.

Is it possible to prevent myotonic dystrophy?

It is not possible to prevent myotonic dystrophy because it is an inherited condition. However, if a person receives treatment for their symptoms, this can helpTrusted Source alleviate some of the effects of the condition and improve quality of life.

Frequently asked questions

Here are answers to common questions about myotonic dystrophy.

How long can a person live with myotonic dystrophy?

How long a person lives with myotonic dystrophy depends on the type and severity of the condition. If a person has mild DM1, the condition may not affect their life expectancy. With classic DM1, life expectancy is around 48–55 yearsTrusted Source. It is around 45 years for congenital DM1. DM2 typically does not affect life expectancy.

What is the age of onset for myotonic dystrophy?

People with DM2 typically begin to experience symptoms around 48 years of ageTrusted Source, though it may begin earlier or later. DM1 symptoms present at different points in a person’s life depending on severity. With mild DM1, symptoms typically begin after the age of 40 years, though they can begin anywhere from 20–70 years.

Those with classic DM1 may start experiencing signs and symptoms from when they are 10 to anytime in their 30s. Childhood myotonic dystrophy typically begins around the age of 10 years, while congenital myotonic dystrophy may be present from birth.

What is the most common cause of death in myotonic dystrophy?

The most common cause of death in myotonic dystrophy is respiratory failure, with cardiac complications being the second most common.

Summary

Myotonic dystrophy is the most common type of muscular dystrophy that begins in adulthood. It is an autosomal dominant condition, which means that people only need to inherit one gene relating to the condition to develop symptoms.

There are different types of myotonic dystrophy. DM2 tends to be milder than DM1. DM1 typically has more severe symptoms and can cause intellectual disabilities in some people.

There currently is no treatment for myotonic dystrophy, but treatments can help manage symptoms.

Source - Medical News Today