Muscles: How ToTurning Energy into Motion

Most of us take our muscles for granted, not realizing how crucial they are to us. Muscles are the body’s engine, and energy is the fuel. It would be impossible for us to do anything without them, including expressing ourselves. We convey ideas through spoken words using the muscles of the mouth, tongue and larynx, through written words using the muscles of the fingers, or through body language using skeletal muscles.

The human body contains more than 630 muscles. Approximately 35-45% of body mass is muscle tissue. Muscles are long- lasting, self-healing and grow stronger with use. There are three unique kinds of muscle:

• Cardiac muscle, which is found only in your heart. It contracts involuntarily; it is automatically controlled by the nervous system.
• Smooth muscle is found in blood vessels, the digestive system, bladder, airways, and the uterus in a female. It also contracts involuntarily.
• Skeletal muscle is the kind we can see and feel. They attach to the skeleton and come in pairs; one muscle to move in one direction and another to move back the other way. Skeletal muscles contract voluntarily, you have to think about contracting them and the nervous system tells them to respond.

The combination of muscles and bones make up the musculoskeletal system. Together, the skeletal muscles work with bones to give the body its power and strength.

In most cases, skeletal muscle is attached to one end of a bone, stretches across a joint, and then attaches again to another bone. Tendons serve as connector pieces between muscle and bone; when a muscle is contracted, the tendon and bone move along with it.

Skeletal muscles come in a variety of sizes and shapes depending on their job. The muscles in your back, near the spine, are some of the biggest and most powerful. These muscles have the difficult job of keeping the body upright and providing the power to lift and push.

Your face also has plenty of muscles, over 30 as a matter of fact. Facial muscles don’t all attach directly to bone like those in the rest of the body. Many of them attach under the skin, which allows for more control. Contracting your facial muscles ever so slightly can create different looks like happiness, sadness, surprise, and frowning. Eye muscles are the busiest muscles in the body, moving more than 100,000 times a day!

The tongue is a muscle that’s attached only at one end. The tongue is made of a group of muscles that work together, allowing you to talk and help you chew food. It takes 72 different muscles interacting with one another to produce human speech.

The largest muscle in the body is in the buttocks and is called the gluteus maximus.

There are many problems which can affect muscles, causing pain and/or weakness. Some of the most common and least severe muscle disorders include:

• Sprain: A stretched or torn ligament. Wrist and ankle sprains are common and can be caused by falling or twisting.
• Strain: A stretched or torn muscle or tendon. Strains can happen suddenly or develop over time. Hamstring and back muscle strains are most common and are usually caused by twisting or pulling of the tissues. Many people suffer strains from playing sports.
• Muscle cramps: Sudden, involuntary contractions or spasms in the muscle, also called charley horse. Muscle cramps often occur after exercise or at night and can be caused by dehydration, strain or overuse of a muscle, lack of minerals in your diet, or insufficient blood supply to your muscles.
• Tendinitis: Inflammation of a tendon, usually occurring in the elbows, knees, shoulders, hips, heels or wrists. Certain diseases such as rheumatoid arthritis can cause tendinitis, but it is most commonly caused by injuries and overuse.

There are also many more serious muscle disorders such as cancers, diseases of the nerves that affect the muscles, and genetic diseases.

The old adage “an ounce of prevention is worth a pound of cure” comes to mind when considering muscles. Use your muscles and strengthen them, you will need them to carry out everyday tasks and prevent you from falling and breaking bones as you grow older.

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Stem Cells Used For Prostate Regeneration

Stem cells can generate into many types of cells in the body. In a recent study Genentech scientists in San Francisco say they have grown entire prostates in mice using only a single adult stem cell. The success of the study was made possible by identification of a genetic signature which distinguished stem cells from other cells. The information has not been confirmed in humans, but understanding normal cells should help with the understanding of how prostate cancer develops.

Some scientists consider that stem cells in normal tissues produce cancer. Study co-author Leisa Johnson, a senior scientist with Genentech said that has not been proven. Stem cells have several surface markers, but they are also on other cells, making identification difficult. The study authors found a new marker, CD117, combined with previously known prostate stem cell cancer markers. This allowed identification of a single, normal prostate stem cell. That cell was able to generate a functional prostate and was capable of renewing itself. This holds the promise of treatments and even cures for many diseases.

Johnson explained that it is important to define a normal cell compartment that can generate a tissue. Once that knowledge is available it would be able to identify the compartment that goes awry if cancer initiates. What is resistant, what is regenerating a tumor, is the same cell responsible for generation of normal tissue?

According to Paul Sanberg, professor of neurosurgery and director of the University of South Florida Center of Excellence for Aging and Brain Repair in Tampa “It’s another step showing that stem cells can be a root case of cancer, so it gives targets for treatment.”

Wei-Qiang Gao, Ph.D. also of Genentech said that same kind of cells carrying the same CD117 marker can be found in humans. According to Gao and colleagues two different research teams recently reported growing mouse mammary glands from a single stem cell. The finds add to this “hallmark advancement in the stem-cell research field.” Researchers grew their transplant cells in gel in the lab, and when the gels were placed inside the kidneys of immune-deficient mice, they grew into functional prostrate tissue.

There were 97 single cell transplants, and 14 developed functioning prostates. This may seem like a low percentage of success, but since it is the first attempt it is an extremely significant process.

Stem cells have had scientists extremely interested in recent years because of the potential to grow specific cells to replace damage or diseased tissue. The interest has also generated a lot of public controversy because the biggest focus has been on embryonic cells. Embryonic cells are “pluripotent” and can become any tissue in the body. There are “unipotent” adult stem cells which are already programmed to divide into specific cells. These were the cells used in this research. Isolating “unipotent” cells and getting them to regenerate into the desired tissue has been a major hurdle. Future medical research will show whether tailor made transplants can be grown from a patient’s own cells by using the findings of this study.

The prostate is a small gland located just below the bladder that helps make seminal fluid and expel semen. Prostate cancer is one of the most prominent cancers in developed countries. Even if non-cancerous prostates cause many medical problems for the aging male population.

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Circumcision Doesn’t Reduce Male-to-Female Transmission of HIV

In recent years, the male foreskin—a double-folded tube of skin and mucous membrane that covers the head of the penis—has taken center stage in the battle against HIV. The foreskin is rich in Langerhans cells, immune cells that are particularly easy for the virus to access. Following infection, these cells not only serve as reservoirs for replicating the virus, but also transport it to nearby lymph nodes where HIV spreads to other immune cells. Studies have shown that removal of the foreskin can reduce a man’s risk of heterosexually acquired HIV infection by 50 to 65 percent, findings that prompted large-scale circumcision campaigns in countries with high infection rates, such as sub-Saharan Africa, where heterosexual sex is primarily responsible for the HIV epidemic. Studies had also suggested that circumcision could reduce the rate of male-to-female transmission of the virus, but that turns out not to be the case.

A Ugandan study, led by Dr. Maria J. Wawer of Johns Hopkins Bloomberg School of Public Health in Baltimore, was stopped early after it became apparent that male circumcision offered no protection to female partners. The study involved 922 uncircumcised, HIV-infected men between 15 and 49 years of age who were randomly chosen to either be circumcised or remain uncircumcised. The HIV-free female partners of the male participants were also enrolled in the study, 90 in the circumcised group and 70 in the uncircumcised group, and their HIV status was evaluated after 6, 12 and 24 months. All participants were intensively schooled in HIV prevention and provided free condoms.

After two years, 18 percent of the women in the circumcised group had become infected with HIV, compared with 12 percent in the uncircumcised group. Cumulative probability of HIV infection at 24 months was 22 percent among women in the circumcised group and 13 percent among those in the uncircumcised group. The majority of the infections in the circumcised group occurred within the six months following the procedure. The researchers said the infections were caused because some of the men had intercourse before their circumcision wounds had healed, exposing their female partners to HIV-infected blood in the vagina.

The researchers said though they were disappointed with the outcome of the study, circumcision campaigns are still valid. “The efficacy of male circumcision for prevention of HIV in uninfected men is clear, and reductions in male acquisition of HIV attributable to circumcision are likely to reduce women's exposure to HIV-infected men. Male circumcision programs are thus likely to confer an overall benefit to women," the researchers concluded.

In an editorial accompanying the study, Dr Jared M. Baeton, from the University of Washington in Seattle, and colleagues stressed the importance of circumcision programs for men at risk of HIV, and argued for more effort being focused on people in relationships where one partner is HIV-infected and the other is not. “Prevention services for this population, including HIV testing for couples, facilitated disclosure of HIV seropositivity, and ongoing counseling services, should be a public health priority,” they write. “Such services should be incorporated into male circumcision programs, thereby providing further protection to HIV uninfected women.”

An estimated 33 million people worldwide are living with HIV/AIDS, but the World Health Organization (WHO) says circumcision has the potential to dramatically reduce the toll of the virus, averting an estimated 5.7 million new infections and three million deaths over the next 20 years in sub-Saharan Africa alone.

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Genetic Traits Link to Bipolar Disorder

Two genes in the brain that control the activity of the nerve cells may play a big role in a person's risk for developing bipolar disorder, which is marked by dramatic swings from being depressed to manic behavior and affects between one and three percent of the population worldwide. While identifying these genes is important, it is not expected that it will lead to a genetic test for the risk of bipolar disorder. It could, however, help unravel the mystery of how it arises and could lead to better treatments

A team of international scientists examined the genomes of approximately 10,956 people that were mainly from the United States and Britain. This was including 4,387 people with the disorder, also often known as manic-depression.

The scientists found that the people with the disorder were more likely to have certain variants of the ANK3 and CACNA1C genes. The proteins that these two genes make help govern the flow of calcium ions and sodium in and out of neurons in the brain, which in turn influences the activity of the nerve cells.

The person who helped lead the study, Nick Craddock of Britain's Cardiff University, said, "The key importance of this is that it gives us a clear idea of the sorts of chemicals and mechanisms in the brain that are involved in bipolar disorder. Over a number of years, that will help researchers to develop better approaches to diagnosis and treatment."

Because this disorder has a history of running in families, scientists have been trying to pinpoint the genes that are involved in bipolar disorder. This study was the largest genetic analysis of it kind on bipolar disorder.

This disorder of the brain can cause extreme shifts in mood, energy and general ability to function. Bipolar disorder is marked by high periods of elation or irritability which is followed by periods of sadness and hopelessness that could last for months.

The researchers stated that proper function of neurons in the brain depends on a delicate balance between of calcium and sodium. Our brains operate on how quickly sodium and calcium are moving in and out of cells and the amount that goes in and out. The findings of this study suggest that this disorder may stem at least in part from malfunctions in the flow of these ions, which are the chemicals that are electrically charged.

There is a need for much better treatment for this disorder. Lithium, which is the most common treatment, only helps about two-thirds of those with bipolar disorder and can cause mild shakiness, drowsiness, and weight gain.

The research was funded in part by the U.S government's National Institutes of Health. The director of the NIH's National Institute of Mental Health, Dr. Thomas Insel, said that the findings may help solve the puzzle that is bipolar disorder. "It's not going to tell us the whole story -- it doesn't give you the whole puzzle -- but it's something to build on."

Craddock said that identifying the two gene variants will probably not be helpful in determining a person's risk for bipolar disorder because many people who do not have this disorder will have the same genes.

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Rituxan + Chemo Helps Fight Leukemia

Patients with relapsed Chronic Lymphocytic Leukemia (CLL) can benefit from a combination of treatment through fludarabine and cyclophosphamide chemotherapy along with Rituxan, a drug sold by Genetech Inc. and Biogen Idec Inc. The combination treatment has proven to raise the survival rate for patients with CLL and warded off the progression of the cancer.

Recently, a study called REACH—the second to evaluate the success of combination treatment with Rituxan and chemotherapy as a fight against CLL—showed great success. According to the American Cancer Society, CLL is the most common form of adult leukemia and will affect around 15,000 people this year. Leukemia, which means "white blood," is a broad term that represents a range of diseases. It is a cancer that attacks a patient’s blood and bone marrow where blood cells are made.

Rituxan is approved for several uses. Its initial purpose was to treat non-Hodgkin’s lymphoma, which it was approved to treat in 1997. Since then it has been approved for other uses including rheumatoid arthritis. During the study REACH, researchers evaluated 552 random study patients that were previously unsuccessfully treated for CLL. REACH compared the results from patients treated with the combination treatment of Rituxan and chemotherapy, and those only treated with chemotherapy, to see which group reached greater results at increasing progression free survival. Based on the study, those patients treated with the combination of Rituxan and chemotherapy improved their progression free survival rates more than those patients treated with only chemotherapy.

Based on the successful results of REACH, the makers of Rituxan hope to gain approval from the FDA for another treatment option for CLL. The President of Research and Development with Biogen Inc, Cecil Pickett stated “REACH results are promising, and pending confirmation of the results by independent review, we look forward to submitting an application to the FDA for Rituxan’s potential approval in this indication.”

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