CHAMPAIGN, Ill. — For decades, scientists assumed that the ovary alone produced steroid hormones during pregnancy. In a new study in mice, however, researchers demonstrate that once an embryo attaches to the uterine wall, the uterus itself actually synthesizes the estrogen needed to sustain the pregnancy.
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Aggressive forms of cancer are often driven by the abnormal over-expression of cancer-promoting genes, also known as oncogenes.
Studies at the Genome Institute of Singapore (GIS), a research institute under the Agency for Science, Technology and Research (A*STAR) of Singapore, have identified a gene, known as RCP (or RAB11FIP1), that is frequently amplified and over-expressed in breast cancer and functionally contributes to aggressive breast cancer behaviour.
Research suggests that African Americans with HIV have a unique survival advantage if they have both a low white blood cell count (known as leukopenia) and a genetic variation that is found mainly in persons of African ancestry. This study was prepublished online on July 20, 2009, in Blood.
The research showed that African Americans with HIV who possess both a variation in the gene for the Duffy antigen receptor for chemokine (DARC) and leukopenia have slower HIV-to-AIDS progression rates than HIV-infected European Americans with leukopenia.
After the disbandment of the STEP trial to test the efficacy of the Merck HIV-1 vaccine candidate in 2007, many explanations for why the vaccine was ineffective have been circulating. They revolve around the hypothesis that high levels of baseline Ad5-specific neutralizing antibodies could have increased HIV-1 acquisition among the study subjects who received the vaccine. By increasing Ad5-specific CD4+ T-cells that were susceptible to HIV-1 infection, subjects may have actually become more vulnerable to the virus.
In a proof-of-concept study, Mayo Clinic investigators have demonstrated that induced pluripotent stem (iPS) cells can be used to treat heart disease. iPS cells are stem cells converted from adult cells. In this study, the researchers reprogrammed ordinary fibroblasts, cells that contribute to scars such as those resulting from a heart attack, converting them into stem cells that fix heart damage caused by infarction. The findings appear in the current online issue of the journal Circulation.
Surgically removing and evaluating an increasing number of lymph nodes does not appear to identify a greater number of patients with stage III colorectal cancer, according to a report in the July issue of Archives of Surgery, one of the JAMA/Archives journals.
Mild facial nerve paralysis caused by the use of forceps during birth generally resolves on its own and does not require treatment, according to a report in the July issue of Archives of Otolaryngology–Head & Neck Surgery, one of the JAMA/Archives journals.
Two and a half years after children with sleep-related breathing disorders had surgery to remove their tonsils and adenoids (glands in the back of the throat), the results are promising, according to a report in the July issue of Archives of Otolaryngology–Head & Neck Surgery, one of the JAMA/Archives journals. Patients reported better sleeping than prior to the surgery, but not as continuous as the months immediately following the procedure.
About one-fourth of patients with superficial vein thrombosis—clotting in blood vessels close to the skin—also may have the life-threatening condition deep vein thrombosis, according to a report in the July issue of Archives of Dermatology, one of the JAMA/Archives journals.
Two genes may contribute to chemotherapy resistance in drugs like 5-fluorouracil, which is used in liver cancer treatment, according to Virginia Commonwealth University Massey Cancer Center researchers.
Liver cancer is highly aggressive and has limited therapeutic options. One of the key challenges with cancer treatment is that patients can develop resistance to chemotherapy. Researchers are examining ways to prevent resistance by determining the molecular mechanisms involved with cancer progression, and then developing new generations of chemotherapeutic agents.
Researchers have discovered that the sea lamprey, which emerged from jawless fish first appearing 500 million years ago, dramatically remodels its genome. Shortly after a fertilized lamprey egg divides into several cells, the growing embryo discards millions of units of its DNA.
Transoral (through-the-mouth) laser surgery to remove cancer at the base of the tongue is as effective as more invasive, open surgery, and may improve quality of life according to a new study by Rush University Medical Center. The study is published in the July issue of the scientific journal Otolaryngology –Head and Neck Surgery.
Most evolutionary changes happen in tiny increments: an elephant grows a little larger, a giraffe's neck a little longer. But when it comes to traits like the number of wings on an insect, or limbs on a primate, there is no middle ground. There is still a question of how these sorts of large evolutionary leaps are made
Kaiser Permanente researchers showed that the Anti-Retroviral Therapy (ART) used in the treatment of HIV has an equal effect on patients, regardless of race. This is contrary to earlier studies that showed a tendency for poorer results among Hispanics and African Americans when compared with caucasions.
The study, which appears in The Journal of General Internal Medicine, is one of the largest to date to evaluate racial and ethnic differences in clinical outcomes among HIV-infected patients.
PHOENIX, Ariz. – July 20, 2009 – California and Arizona researchers have identified a gene variant that carries nearly twice the risk of developing an increasingly common type of blood cancer, according to a study published online today by the science journal Nature Genetics.