A blog for Biomedical Laboratory Science, Clinical Laboratory Medicine, Medical Laboratory Technology with relevant news, abstracts, articles, publications and pictures for lab medicine professionals, students and others
The prostate-specific antigen test is a blood test that measures levels of a protein the prostate gland produces. Men with prostate cancer usually have elevated levels of this protein, but heightened levels do not always mean cancer.
Other health conditions may also cause prostate-specific antigen (PSA) levels to rise. In some cases, an elevated PSA is temporary and not a sign of a health problem at all.
Cells in the prostate gland produce PSA and levels typically remain below 4 nanograms per milliliter (ng/mL).
Most men with prostate cancer have PSA levels above 4 ng/mL, but about 15 percent of men with a PSA level below 4 ng/mL are also diagnosed with prostate cancer. This means that a PSA test alone cannot rule out or diagnose prostate cancer but can identify whether a man is at higher risk of having or developing the disease.
Initial testing may include both a PSA test and a digital rectal exam (DRE). During this examination, a doctor inserts a finger into the rectum to check the prostate for abnormalities. Together, if these two tests suggest prostate cancer, then the doctor will arrange for a biopsy to confirm the diagnosis.
False positives - a high PSA level, but no cancer - on the PSA test are common. PSA levels rise with age and other factors. Men with high PSA levels should follow up with a doctor, but should not assume they have cancer.
A high PSA level may not always indicate prostate cancer.
Can tissue engineering provide a cheap and convenient alternative to surgery for eardrum repair?
In the most severe cases, a ruptured eardrum can require surgery to put it right, but tissue-engineering techniques might provide a much simpler solution.
The eardrum, or tympanic membrane, forms the interface between the outside world and the delicate bony structures of the middle ear — the ossicles — that conduct sound vibrations to the inner ear. At just a fraction of a millimetre thick and held under tension, the membrane is perfectly adapted to transmit even the faintest of vibrations. But the qualities that make the eardrum such a good conductor of sound come at a price: fragility. Burst eardrums are a major cause of conductive hearing loss — when sounds can't pass from the outer to the inner ear.
Most burst eardrums are caused by infections or trauma. The vast majority heal on their own in about ten days, but for a small proportion of people the perforation fails to heal naturally. These chronic ruptures cause conductive hearing loss and increase the risk of middle ear infections, which can have serious complications.
Hepatitis C (HCV) is a viral infection that affects the liver and an estimated 3.2 million people in the USA are infected with HCV, and most do not feel ill or know that they are infected. Since 2010, acute cases of HCV have more than doubled, with new cases predominantly among young, white individuals with a history of injection drug use.
The current recommendations are that doctors screen patients at high-risk for contracting HCV, which include but are not limited to people born between 1945 and 1965, those diagnosed with HIV, children born to HCV-positive women and individuals who engage in injection drug use (PWID), among other select populations at high risk. This strategy is called "targeted" screening. "Routine" screening, as defined in the study, tests all individuals in a community with a high prevalence of HCV.
Video: One step Hepatitis C Virus Test Cassette, Raecho International
There are two ways to perform these screenings. Rapid testing is when results are given on the same day that the sample is drawn. Standard testing requires patients to return for a second appointment to get the results. Scientists at Boston Medical Center (Boston, MA, USA) and their colleagues evaluated the clinical benefits and cost-effectiveness of testing strategies among 15 to 30-year-olds at urban community health centers. They developed a decision analytic model to project quality-adjusted life years (QALYs), lifetime costs (2016 USDs) and incremental cost-effectiveness ratios (ICER) associated with nine strategies for one-time testing. The strategies differed in three ways: targeted versus routine testing; rapid finger stick versus standard venipuncture; and ordered by physician versus counselor/tester using standing orders.
Illustration of the Hepatitis C Virus
The team found that compared to targeted risk-based testing (current standard of care), routine testing increased lifetime medical cost by USD 80 and discounted QALYs by 0.0013 per person. Across all strategies rapid testing provided higher QALYs at a lower cost per QALY gained, and was always preferred. Counselor-initiated routine rapid testing was associated with an ICER of USD 71,000/QALY gained. Results were sensitive to offer and result receipt rates. Counselor-initiated routine rapid testing was cost-effective (ICER greater than USD 100,000/QALY) unless the prevalence of PWID was greater than 0.59%, HCV prevalence among PWID less than 16%, reinfection rate greater than 26 cases per 100 person-years, or reflex confirmatory testing followed all reactive venipuncture diagnostics.
Sabrina A. Assoumou, MD, MPH, an infectious disease physician and lead author of the study, said, “When standard testing was applied, patients were less likely to come back for that second appointment to get their results, which in turn meant more people weren't getting the treatment they so desperately needed. Our results indicate that we must initiate rapid testing strategies so that more people will know their status and get treatment more quickly.” The study was published on September 9, 2017, in the journal Clinical Infectious Diseases.
So, you’re looking to shed a pound or two. Time to cut back on those pesky calories, right?
Not so fast. According to Michelle Adams-Arent, a sports nutrition consultant and the Director of Science and Education for Metabolic Precision, reducing your food intake might not work like you originally thought. In fact, it might actually backfire.
'Your body is built for survival,' Adams-Arent told Business Insider. 'It doesn’t care what you want to look like.'
The minute you start cutting back on your caloric consumption, your body goes into full-on starvation mode. Translation? Your metabolic rate will actually decrease as your body tries to preserve what little nutrition it has. A lower metabolism means fewer calories burned. What’s more, research even shows burning more calories than you consume over a long period of time can increase your body fat. Not exactly the outcome you were hoping for.
HIV stands for human immunodeficiency virus, which is the virus that causes HIV infection. The abbreviation “HIV” can refer to the virus or to HIV infection.
AIDS stands for acquired immunodeficiency syndrome. AIDS is the most advanced stage of HIV infection.
HIV attacks and destroys the infection-fighting CD4 cells of the immune system. The loss of CD4 cells makes it difficult for the body to fight infections and certain cancers. Without treatment, HIV can gradually destroy the immune system and advance to AIDS.
How is HIV spread?
HIV is spread through contact with certain body fluids from a person with HIV. These body fluids include:
Blood
Semen
Pre-seminal fluid
Vaginal fluids
Rectal fluids
Breast milk
The spread of HIV from person to person is called HIV transmission. The spread of HIV from a woman with HIV to her child during pregnancy, childbirth, or breastfeeding is called mother-to-child transmission of HIV.
In the United States, HIV is spread mainly by having sex with or sharing drug injection equipment with someone who has HIV. To reduce your risk of HIV infection, use condoms correctly and consistently during sex, limit your number of sexual partners, and never share drug injection equipment.
Mother-to-child transmission is the most common way that children become infected with HIV. HIV medicines, given to women with HIV during pregnancy and childbirth and to their babies after birth, reduce the risk of mother-to-child transmission of HIV.
You can’t get HIV by shaking hands or hugging a person who has HIV. You also can’t get HIV from contact with objects such as dishes, toilet seats, or doorknobs used by a person with HIV. HIV does not spread through the air or through mosquito, tick, or other insect bites.
The HIV Life Cycle
HIV attacks and destroys the CD4 cells of the immune system. CD4 cells are a type of white blood cell that play a major role in protecting the body from infection. HIV uses the machinery of the CD4 cells to multiply (make copies of itself) and spread throughout the body. This process, which is carried out in seven steps or stages, is called the HIV life cycle.
What is the connection between the HIV life cycle and HIV medicines?
Antiretroviral therapy (ART) is the use of HIV medicines to treat HIV infection. HIV medicines protect the immune system by blocking HIV at different stages of the HIV life cycle.
HIV medicines are grouped into different drug classes according to how they fight HIV. Each class of drugs is designed to target a specific step in the HIV life cycle.
ART combines HIV medicines from at least two different HIV drug classes, making it very effective at preventing HIV from multiplying. Having less HIV in the body protects the immune system and prevents HIV from advancing to AIDS. ART also reduces the risk of HIV drug resistance.
ART can’t cure HIV, but HIV medicines help people with HIV live longer, healthier lives. HIV medicines also reduce the risk of HIV transmission (the spread of HIV to others).
What are the seven stages of the HIV life cycle?
The seven stages of the HIV life cycle are: 1) binding, 2) fusion, 3) reverse transcription, 4) integration, 5) replication, 6) assembly, and 7) budding. To understand each stage in the HIV life cycle, it helps to first imagine what HIV looks like.
Now follow each stage in the HIV life cycle, as HIV attacks a CD4 cell and uses the machinery of the cell to multiply.
This video explains how HIV targets human immune cells, and uses immune cell machinery to make copies of itself. By comparing an analogy to the life cycle of HIV, this presentation will help you understand how HIV systematically reduces immunity within the body.
A new study has investigated how mothers and fathers cause new genetic mutations in their children, and how some of these mutations may lead to negative outcomes.
Characteristics that we inherit from our parents - starting with very basic features such as eye color or hair texture - shape not just our identity, but also the state of our health, both earlier and later in life.
That being the case, the study of genetics has become central to understanding who and what we are, as well as how our bodies are likely to develop in time, and how we might respond to internal or external factors.
For instance, recent studies have revealed the importance of genetic factors to conditions including Alzheimer's disease, brain cancer, and diabetes.
Given the importance of understanding the role of genetic factors to our health profile, scientists are constantly striving to decipher the mysteries of the human genome.
Researchers are looking at how the parents' age and sex determine new genetic mutations in the offspring.
Middle-aged women can choose which test to undergo for cervical cancer screening, according to a draft recommendation from an influential group backed by the U.S. government.
Women ages 30 to 65 can choose to receive a Pap test every three years or a human papillomavirus (HPV) test every five years, according to the U.S. Preventive Services Task Force (USPSTF). The group did not previously recommend HPV testing without a Pap test.
"Women and providers should continue to recognize that cervical cancer is a serious disease that can be prevented," said Dr. Maureen Phipps, a member of the USPTF.
"Women who can be identified early through screening can have effective treatment for cervical cancer and go on to lead robust lives," said Phipps, who is also chair of obstetrics and gynecology at the Warren Alpert Medical School of Brown University in Providence, Rhode Island.
Cervical cancer was once a leading cause of cancer death for women in the U.S., but the death rate has been cut in half thanks mostly to screening, according to the American Cancer Society (ACS).
A tumor marker is a biomarker found in blood, urine, or body tissues that can be elevated by the presence of one or more types of cancer. The vast majority of tumor marker tests in primary and secondary care may not be necessary as the tests assisted with a cancer diagnosis in just 2% of patients.
Tumor markers are molecules, which may be present in higher than usual concentrations in the tissue, serum or other body fluids of patients with cancer. There are many different tumor markers, each indicative of a particular disease process, and they are used in oncology to help detect the presence of cancer. A tumor marker can be used to aid diagnosis in specific situations but testing for more than one marker is not recommended.
Scientists at South West Wales Cancer Centre (Cardiff, UK) examined the number of multiple tumor marker requests from primary and secondary care over a six-month period within Abertawe Bro Morgannwg University Health Board (Bagain, Neath Port Talbot, Wales). Multiple requests were defined as more than one tumors marker for a patient in a two-week period. The team looked at how many patients with multiple tumor markers measured were subsequently diagnosed with cancer, and whether the markers assisted with the diagnosis.
Common tumor markers used in the diagnosis of cancer
Diabetes, or diabetes mellitus (DM), is a metabolic disorder in which the body cannot properly store and use sugar.
It affects the body's ability to use glucose, a type of sugar found in the blood, as fuel. This happens because the body does not produce enough insulin, or the cells do not correctly respond to insulin to use glucose as energy.
Insulin is a type of hormone produced by the pancreas to regulate how blood sugar becomes energy. An imbalance of insulin or resistance to insulin causes diabetes.
Diabetes is linked to a higher risk of cardiovascular disease, kidney disease, vision loss, neurological conditions, and damage to blood vessels and organs.
There is type 1, type 2, and gestational diabetes. They have different causes and risk factors, and different lines of treatment.
This article will compare the similarities and differences of types 1 and 2 diabetes.
People with type 1 diabetes will require supplemental insulin on an
ongoing basis. People with type 2 will likely only need this for the later
stages of the condition. A healthcare specialist will be able to test
a patient for diabetes, even if type 2 diabetes shows no symptoms.
According to a comprehensive new report from the Food and Agriculture Organization of the United Nations, one in 10 of the world's 7.5 billion inhabitants is obese. At the same time, rates of people who are starving or malnourished is on the rise.
According to Business Insider, nutritionists and public health experts say both issues can be traced to our diet.
Today, food that is more highly processed and calorie-dense is available worldwide. And it's relatively cheap, too.
