Biomedical Laboratory Science

Saturday, August 13, 2016

Thyroid Hormone Receptors and Resistance to Thyroid Hormone Disorders

Thyroid hormone action is predominantly mediated by thyroid hormone receptors (THRs), which are encoded by the thyroid hormone receptor α (THRA) and thyroid hormone receptor β (THRB) genes. Patients with mutations in THRB present with resistance to thyroid hormone β (RTHβ), which is a disorder characterized by elevated levels of thyroid hormone, normal or elevated levels of TSH and goitre.

Mechanistic insights about the contributions of THRβ to various processes, including colour vision, development of the cochlea and the cerebellum, and normal functioning of the adult liver and heart, have been obtained by either introducing human THRB mutations into mice or by deletion of the mouse Thrb gene. The introduction of the same mutations that mimic human THRβ alterations into the mouse Thra and Thrb genes resulted in distinct phenotypes, which suggests that THRA and THRB might have non-overlapping functions in human physiology.

These studies also suggested that THRA mutations might not be lethal. Seven patients with mutations in THRα have since been described. These patients have RTHα and presented with major abnormalities in growth and gastrointestinal function. The hypothalamic–pituitary–thyroid axis in these individuals is minimally affected, which suggests that the central T3 feedback loop is not impaired in patients with RTHα, in stark contrast to patients with RTHβ.

Overview of tissues and homeostatic functions affected in RTHα and RTHβ.

Source: NatureReviewsEndocrinology

'Living' Cartilage Grown Using Stem Cells Could Prevent Hip Replacement Surgery

An alternative to hip replacement surgery may be in sight. In the Proceedings of the National Academy of Sciences, researchers reveal how it may be possible to use a patient's own stem cells to grow new cartilage in the shape of a hip joint.

Furthermore, the team - including researchers from Washington University School of Medicine in St. Louis, MO - says it is possible to program the newly grown cartilage to release anti-inflammatory molecules, which could stave off the return of arthritis - the most common cause of hip pain.

According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), osteoarthritis is the primary cause of hip joint damage that requires hip replacement surgery, causing severe pain and disability.

Hip replacement surgery, also known as arthroplasty, involves surgically removing the diseased part of the hip and replacing it with new, prosthetic parts. Each year in the United States, more than 332,000 hip replacement surgeries are performed.

Researchers describe how they could use a patient's own stem cells to grow new cartilage that covers

a 3-D scaffold molded to the shape of their hip joint.

Source: medicalnewstoday

Afraid of Failure? Think Like a Scientist and Get Over It

I recently had a wonderful conversation with my friend, Beck Tench. During our chat, Beck told me about an interesting shift in thinking that occurred while she worked at a science museum.

During her time there, Beck said that she learned how to treat failure like a scientist.

How does a scientist treat failure? And what can we learn from their approach?

Here’s what Beck taught me…

Source: entrepreneur

Osteoarthritis can be Caused by Senescent Cells

Researchers have uncovered evidence that cellular senescence - whereby cells stop dividing - is a cause of osteoarthritis, and they suggest targeting these cells could offer a promising way to prevent or treat the condition.

Study co-author Dr. James Kirkland, director of the Robert and Arlene Kogod Center on Aging at Mayo Clinic in Rochester, MN, and colleagues publish their findings in The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences.

Osteoarthritis (OA), also known as degenerative joint disease, is a condition in which cartilage - the tissue that protects the end of each bone in a joint - wears away, causing the underlying bones to rub together. This can cause pain, swelling, and poor joint movement.

As the condition worsens, the bones may lose shape. Additionally, growths called bone spurs may arise, and bits of bone and cartilage can break off and float around the space in the joint. This can trigger an inflammatory response that exacerbates pain, as well as cartilage and bone damage.

Researchers say that targeting senescent cells may have the potential to prevent or treat osteoarthritis.

Source: medicalnewstoday

Thursday, August 11, 2016

Blood test for Tuberculosis

Together with AIDS, tuberculosis ranks among those infectious diseases with the highest global mortality rate, claiming the lives of between 1.5 and two million people every year. However, not everyone infected with the bacterium develops tuberculosis. In fact, fewer than ten percent of those infected go on to manifest the disease. An international team of scientists, including researchers from the Max Planck Institute for Infection Biology in Berlin, have now developed a tuberculosis test that can reliably predict whether an individual will develop active tuberculosis. Doctors may be able to use this test in future to predict the progression of the disease and initiate medical care early.

In future, molecules from blood samples can tell physicians if somebody will develop tuberculosis.

How Hepatitis C Spreads

You may have heard of hepatitis C (HCV or hep C), the potentially deadly virus that causes liver inflammation. HCV often produces no symptoms until it reaches an advanced stage, which makes it hard to know you’ve been infected. However, if you understand the ways in which hep C spreads, you can take precautions to reduce your risk of contracting this virus.

What is hepatitis C?

Hepatitis, in general, refers to liver inflammation. Many things can cause liver inflammation, including toxic chemicals, medications and drug or alcohol abuse. These types of hepatitis sometimes clear up on their own and may not even require treatment.

Poor Protein Control Key to Alzheimer's Progression

Despite decades of research, the molecular mechanisms behind Alzheimer's disease are poorly understood. New research investigating the pattern of protein build-up in Alzheimer's brains may open the door to a deeper understanding.

Alzheimers is the most common form of dementia, with an estimated 5 million Americans living with the disease today.

It is a progressive condition, normally appearing around the age of 60.

Alzheimer's disease begins with mild memory loss and can end with the individual losing touch with the environment around them.

Although a great deal has been learned about the disease, there is no cure, and many questions remain unanswered.

Alzheimer's is characterized by a build-up of proteins in the brain, known as plaques and tangles.

Mapping the way in which protein is managed in the brain gives fresh insight into Alzheimer's.

Source: medicalnewstoday

Sleep Problems Could Mean Higher Stroke Risk

That said, researchers stopped short of recommending drug treatment for sleep-wake disorders.

If you're having trouble sleeping at night, your problems could be worse than just being tired: Both insomnia and oversleeping could increase your risk of having a stroke.

New findings, published Wednesday in Neurology, indicate that sleep disorders, like insomnia and sleep apnea, are associated with stroke risk and could hamper stroke recovery. Researchers combined data from multiple studies that focused on the sleep-stroke connection.

"Although sleep disorders are common after a stroke, very few stroke patients are tested for them," said study author Dr. Dirk M. Hermann in a statement. "The results of our review show that should change, as people with sleep disorders may be more likely to have another stroke or other negative outcomes than people without sleep problems, such as having to go to a nursing home after leaving the hospital."

Both insomnia and oversleeping could increase your risk of having a stroke.

Source: msn.com/en-us/health/medical

Video: Sleep and Stroke Risk

Tuesday, August 9, 2016

High-Fat Diet in Pregnancy Reduces Beneficial Gut Microbiota for Offspring

Eating a high-fat diet during pregnancy could alter the population of gut microbiota in offspring, which may have negative implications for nutrition and development. This is the conclusion of a new study published in the journal Genome Medicine.

It is well established that what women eat and drink during pregnancy can influence the health and development of their child.

For example, it is recommended that expectant mothers consume 0.4 milligrams of folic acid every day in order to help prevent certain birth defects, and current advice says a healthy, balanced diet is best for both mother and baby.

Women who eat a high-fat diet in pregnancy may be putting their offspring's health and development at risk,
say researchers.

Biomedical Laboratory Science