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The issue with performing angioplasty, a technique used to widen blood vessels, in hospitals without proper surgical units has long been a controversial topic. Many cardiologists claim that the lack of emergency care can lead to increased adverse events.
For the last 40 years, heart transplantation has been the golden standard therapy for patients who suffer from end stage heart failure, a condition in which the heart is unable to pump the blood to the rest of the body sufficiently. A clinical study conducted by the Hopkins Division of Cardiac Surgery sets itself apart from other studies done on heart transplantation, as it observed long-term factors that impacted survival rates of patients. The Hopkins surgical division conducted a 10-year multivariate analysis on post-transplantation patients to identify factors that affected the long-term survival rate of these patients. Their study determined that recipient age, race, ischemic time, donor age and the center volume have significant impact on post-operative survival. The patient population included those who underwent heart transplantation between 1987 and 1999. There was a positive correlation of increased survival rates with later transplant years, an indication that heart transplantation conditions are gradually improving. In other words, those who underwent surgery in 1999 had a larger chance of surviving than those who underwent surgery in 1987. As other studies have consistently indicated, the donor recipient age is a principal factor of survival. As age increases, recipients have a larger chance for encountering adverse factors, such as infection or other organ failures. A great number of elder patients experience infections due to the decline in their immune system. They are also increasingly vulnerable to renal failure. Disparities in survival rates have also been demonstrated between races. White patients constituted a majority of those who survived more than 10 years. Whether this is rooted in biological or socioeconomic differences is not clear. Further research is warranted. The necessity of mechanical ventilation during the wait for receiving a donor decreased odds for 10-year survival as well. Mechanical ventilation is a method that assists spontaneous breathing. Frequently, patients with heart failure require mechanical ventilation to maintain sufficient oxygen supply. These patients typically must remain in the hospital for intensive care. This increases the risk for nosocomial infections - infections acquired within the hospital setting - nutritional depletion and generalized deconditioning. While the recipient's age significantly influences survival rates, the donor's age is also a major factor in predicting long-term survival. Mostly, this is because organ quality is observed declines with age. Older hearts are also more susceptible to longer ischemic time, which is the period of time when the heart is not supplied with oxygen, between its harvest and transplantation. Of course, ischemic time is another variable included in this study, as an increase in ischemic time could greatly affect donor organ quality. Another variable considered in this multivariate study was the center volume, or the frequency of heart transplantation surgeries in each hospital. With increasing surgical experience and resources, and better accommodations for heart transplantation patients, does hospital care have any effect in long-term survival rates? According to data, the threshold value of nine transplantations per year in a hospital seems to have a positive impact on the admitted patient. Although this was a very elaborate study, there were limitations inherent to any study that examines such multivariate subjects, especially in long-term cases. Limitations include the effect of ventricular assist devices. Ventricular assist devices (VAD) are devices implanted to directly facilitate the pumping of blood by the heart. Recently, VADs have been a very attractive option for patients who are waiting to be matched with a donor, which may take months. Other variables include the preservation methods of the donor hearts. This study examined patients who received heart transplantations between 1987 and 1999. Since then, surgical technologies and techniques have improved significantly, as well as our understanding of improving quality of life for patients. These are variables that can be included in future studies that investigate long-term post-transplantation survival rates.
A study by UCLA researchers was published on the online edition of Neurotherapeutics that reported the development of a novel drug that could break down harmful protein groups in Parkinson's disease. Known as the "molecular tweezer," the compound was able to degrade protein aggregates implicated in Parkinson's without interfering with brain activity in zebrafish. Parkinson's disease is a neurodegenerative disorder that affects the central nervous system, which is comprised of the brain and spinal cord. A neurodegenerative disorder is one that is caused by the death of a component of the nervous system. In the case of Parkinson's disease, cells in a part of our brain called the "substantia nigra" are killed.
Researchers at the University of North Carolina at Chapel Hill have found promising evidence that suggests a new biomarker for predicting an infant's chances of developing autism. The symptom for what may potentially develop into autism later in an infant's life includes the white matter fiber tract organization in its brain. The white matter of the brain consists of bundles of nerve cells, which connect various regions of the brain (grey matter) to each other. If you compare the brain to computers, the grey matter is like the computer itself, while the white matter is composed of all of the network cables that connect computer together. Participants in the study included 92 infants, who were chosen to be a part of the study due to the onset of autism in their siblings. Having siblings with autism puts one at high risk for developing autism as well. Over a period of 24 months, the infants were monitored via brain imaging scans and behavioral tests. Of the 92 subjects, 28 developed autism. The study focused on 15 white matter fiber tracts in the brain and discovered significant differences in the tracks of children with autism. Tracks are regions that connect brain pathways to one another, and the researchers found that 12 out of 15 tracks contained differences. Researchers used a scale called fractional anisotropy (FA) to measure white matter tract development. FA indicates the restriction of the movement of molecules and operates on a scale between zero and one. A value of zero means that the tested molecule is moving around with no restriction in any direction. A value of one means that the molecule is fully restricted along all directions except one. Coupled with diffusion MRI's, FA values can tell researchers the structure of white matter fibers by tracking the movement of water molecules in the brain. Infants who later developed autism had high FA values at six months after birth. By 24 months, they had lower FA values compared to infants without autism, who had slowly developed their white matter tracts. There was a clear disparity between the development of white matter tracts in the brains of infants who later developed autism and those who didn't. The aberration of fiber pathway development can be a clear biomarker for predicting the onset of autism in infants, especially for those whose siblings have already been diagnosed. This study not only suggests that autism is a whole-brain disorder, but also that the development of autism may be prevented by target intervention during the key periods of brain development in infants.
Yale scientists have discovered a molecular pathway that is implicated in maternally inherited deafness, a discovery that was published in Cell. Not only has this study shed light to the molecular interactions in the pathway, but it also has provided a solution for elucidating tissue specificity of human mitochondrial-based disorders. The mitochondrion is a vital organelle that is considered to be the powerhouse of all of our cells. Through a certain process known as oxidative phosphorylation, mitochondria produce units of energy for our cells to carry out certain cellular activities. Mitochondria have their own DNA, which is maternally inherited and can be subject to mutations that lead to mitochondrial dysfunctions. These dysfunctions are implicated in diabetes, heart disease, cancer, neural degeneration and aging. A milestone in determining the cause of maternally inherited deafness occurred back in 1993, when the A1555G mutation was discovered in human mtDNA (mitochondrial DNA). A1555G denotes a point mutation where an adenine nucleotide is mutated into a guanine in the 1555th nucleotide. More specifically, A1555G is a mutation in the 12S rRNA gene that codes for a certain subunit of ribosomes in mitochondria. This gene was found to cause irreversible deafness, which implies that the crucial, irreplaceable cells within the inner ear were subject to an apoptotic pathway, or cell-death, due to this mutation. A major obstacle in understanding mitochondrial diseases is the elucidation of its tissue specificity. Despite all cells in the body carrying the same mitochondrial mutation, the primary effect of the A1555G mutation is the eventual loss in hearing, in both mice and humans. This suggests that there is a cell-type specific response to the stress caused by the mutation. The A1555G mutation impairs the ribosome, an organelle known for translation, the process in which cellular proteins are built. This can, downstream, cause defects in the process of oxidative phosphorylation, which is important for producing energy for cells. However, it was found that the 12S rRNA was hypermethylated, due a consequent overexpression of mtTFB1, an enzyme that is implicated in methylation. Hypermethylation means that methyl groups were added to the 12S rRNA. The hypermethylation was key to the molecular defects instigating apoptosis. Yale scientists hypothesized that the hypermethylation of 12S rRNA causes a stress signaling pathway that eventually leads to apoptotic susceptibility of cells. A pro-apoptotic transcription factor, E2F1, was identified to be one of the downstream contributors to cell death. Transcription factors, as E2F1, facilitate the expression of other proteins, which in this case are implicated in cell death. This E2F1 pathway may have become a paradigm for other scientists to not focus on the immediate effects of defects in oxidative phosphorylation, but to find a possible link between apoptosis and retrograde signals caused by hypermethylation in mitochondrial ribosomes.
The Institute for Stem Cell Biology and Regenerative Medicine at Stanford University School of Medicine recently published a study on pluripotency in Proceeding of the National Academy of Sciences. The study engages the possibility of repudiating the popularly conceived notion that pluripotency is necessary to achieve transformation from a general cell type into a specific one. Pluripotency is the process by which stem cells become differentiated into specific cell types.
Researchers in the Department of Pathology at the Hopkins School of Medicine suggest that High Resolution Melting (HRM) assays are simple and scalable methods for measuring HIV diversity. The HRM scores could be useful biomarkers to determine when HIV patients were infected.
A new study has confirmed that Ivacaftor, a bioavailable drug taken orally, is an effective treatment for patients with cystic fibrosis.
Headaches, a common nuisance, have been one of the biggest reasons for medical evacuation of military personnel from Iraq and Afghanistan, according to research conducted by Steven P. Cohen, an associate professor of anesthesiology and critical care medicine at the Hopkins School of Medicine.
Recent genomic evidence has shown that the contemporary strain of the Y. pestis bacterium, commonly associated with human infection, is a direct descendant of the bacterium that caused inconceivable devastation in the Middle Ages, when people were convinced the human race was at its end. Genomic structures indicate no significant discrepancies between the two strains — the ancient and the modern — forcing researchers to wonder what made Y. Pestis unthinkably lethal back in the Middle Ages.
The U.S Preventive Services Task Force (USPSTF), a panel of independent experts dedicated to evaluating scientific studies on new treatments, recommended that healthy men should avoid regular PSA (prostate-specific antigen) testing, a common screening test for prostate cancer in men. The USPSTF concluded from scientific studies that PSA testing does not lower the death rate of prostate cancer, due to the post-surgical complications that lead to death of men with even benign tumors.
Researchers at the University of Utah have discovered a new class of compounds that strongly bind to the sugar coating of the AIDS virus, making possible a new ointment that could prevent HIV from infecting host cells.
The unidentified structure of a retroviral enzyme, M-PMV (Mason-Pfizer Monkey Virus) retroviral protease, was remarkably discovered by a group of online gamers recruited by University of Washington, Center for Game Science. Although gaming is a novel, and also quite an unorthodox, means of research, not only did the gamers propose the viral structure to an outstandingly accurate degree, they were also able to solve the lingering mystery, which hampered much progress in HIV drug research for decades, in a mere three weeks.
One of the crucial challenges in the advancement of contemporary medicine is the development of technologies that offer cheap methods for the improvement of health in remote regions in the world. In these disadvantaged areas, hospitals and patients incur a great monetary burden for treatment due to cost of materials, clinical equipment, and operation — luxuries that developing regions cannot easily afford.