MedicalResearch.com Interview with:
Judith Lichtman, PhD, MPH
Associate Professor (with tenure)
Chair, Department of Chronic Disease Epidemiology
Yale School of Public Health
New Haven, CT 06520-803
Medical Research: What is the background for this study? What are the main findings?
Dr. Lichtman: Heart disease in younger women (18-55 years of age) is relatively rare, and represents less than 5% of all heart disease in women; however, young women who present with a heart attack are twice as likely to die in the hospital as compared with a similarly aged man, and this excess mortality risk continues beyond the index event. Delays in seeking prompt care has been suggested as one potential cause for the excess mortality in young women. We were interested in learning about the recognition of symptoms, perceived risk of heart disease, decision-making process to seek medical care, and interactions with the healthcare system among young women who recently had a heart attack. We found that even though the majority of young women presented with chest pain, they also experienced many other symptoms such as fatigue, nausea, muscle pain, and weakness. They commonly attributed symptoms to non-cardiac conditions because they felt they did not experience the “Hollywood Heart Attack” that is commonly portrayed in the media. Interestingly, despite reporting a strong family history of cardiac disease, and having multiple risk factors, many of the women we spoke with did not perceive they were at risk for heart disease, and many were not working with their physicians to manage their risk factors. They were also concerned about being seen as a hypochondriac if they reported their symptoms. Finally, women reported that the healthcare system was not consistently responsive when they reported their symptoms.
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MedicalResearch.com Interview with:
Dr Søren Dalsgaard
National Centre for Register-based Research
Aarhus University Denmark
Medical Research: What is the background for this study? What...
MedicalResearch.com Interview with:
Jacob (Yaqub) HannaM.D. Ph.D.
Kimmel Investigator | NYSCF Robertson Investigator
The Department of Molecular Genetics
Weizmann Institute of Science, Israel
MedicalResearch: Could this be helpful for any individual with infertility problems? Dr Hanna: Our research is focused on taking skin cell samples and converting them into embryonic-like stem cells (iPS cells) via direct reprogramming and without using embryo derived stem cell lines. Then we are focusing in differentiating these male or female iPS lines into sperm cells or oocytes, respectively. We have succeeded in the first and most important step of the process, where we succeed in reaching the progenitor cell state for sperm and egg (we have not achieved mature sperm and eggs ….Very important to emphasize!). So we are now focusing on completing the second half of this process. Once that is achieved this may become useful for any individual with fertility problems.
MedicalResearch: Could this be a viable option ALSO for same-sex couples? What are the prospects for letting gay or lesbian couples produce progenitor cell state cells from their skin cells? For example, is it conceivable that the "second half" of the protocol could some day also be done in vitro (making fully mature sperm and eggs), so that men could produce egg cells and women sperm cells?
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MedicalResearch.com Interview with:Aidan Roche MBBS, PhD, BEng and
Prof Oskar C AszmannMD
Director of the Christian Doppler Laboratory for Restoration of Extremity Function
Division of Plastic and Reconstructive Surgery
Department of Surgery
Medical University of Vienna, Vienna, Austria
Medical Research: What is the background for this study? What are the main findings?
Response: The study was prompted by lack of techniques to restore hand function in patients with global plexopathies with avulsion of the lower roots. In simple terms, this is a tearing injury to parts of the brachial plexus. The brachial plexus is a complex junction of nerves that leaves the spinal cord and supplies the arm. If this junction of nerves is severely damaged, information cannot reach the hand to control it or to receive sensation from it. In some of these cases, traditional reconstructive surgical techniques are only able to restore shoulder and elbow function, not the hand itself. In severe cases, this might leave the patient with a useless hand. In previous clinical studies with existing amputees, advancing research has shown that good prosthetic control can be achieved by selectively transferring nerves. However, our study differs as our patients had intact, but functionless hands. The innovation here was to selectively transfer nerves and muscles to create useable signals for prosthetic control. Together with a comprehensive rehabilitation regime, followed by elective amputation, this formed the bionic reconstruction process. The main finding is that all three patients had excellent hand function restored through bionic reconstruction (as measured by the uniform improvement in all patients in the clinical outcome scores of the Action Research Arm Test, the Disability of Arm, Shoulder and Hand Questionairre, and the Southampton Hand Assessment Procedure and reported in detail in The Lancet).
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MedicalResearch.com Interview with: Fernanda C. Lessa, M.D., M.P.H.
Centers for Disease Control and Prevention
Atlanta, GA
MedicalResearch: What is the background for this study? What are the main findings?Dr. Lessa: The epidemiology of Clostridium difficile has gone through dramatic changes over the last decade. C. difficile has become the most common cause of healthcare-associated infections in US hospitals and it has been also increasingly reported outside of healthcare settings. As the epidemiology of this pathogen changes, it is important to understand the magnitude and scope of this infection in the United States to help guide priorities for prevention.
Main findings:
1) C. difficilewas responsible for almost half million infections and associated with 29,000 deaths in 2011 in the United States
2) Among the patients who developed C. difficile, 83,000 had recurrent infections
3) C. difficile incidence was higher among females, whites, and persons 65 years of age or older
4) Approximately 345,400 infections occurred outside of the hospital indicating that C. difficile prevention should go beyond hospital settings.
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MedicalResearch.com Interview with:
Professor Stephen Peckham
Director, Centre for Health Services Studies
Professor of Health Policy
Department of Health Services Research and Policy
London School of Hygiene and Tropical Medicine
Director, Policy Research Unit in Commissioning and the Healthcare System University of Kent
Medical Research: What is the background for this study? What are the main findings?
Response: Community water fluoridation remains a controversial public health measure. There have been continued debates about both its effectiveness in the prevention of dental caries and also its safety. Previous studies have suggested that there is an association between fluoride ingestion and the incidence of hypothyroidism few population level studies have been undertaken. In April 2014 Public Health England published a monitoring report that used secondary analysis of routine health statistics to identify whether water fluoridation in England was associated with any adverse health outcomes. While hypothyroidism data is available this was not included in their monitoring report. In England approximately 10% of the population lives in areas with community fluoridation schemes and hypothyroidism prevalence can be assessed from general practice data. Tt examine whether there is a relationship – as suggested in smaller studies – we used a cross-sectional study design using secondary data to develop binary logistic regression models of predictive factors for hypothyroidism prevalence at practice level using 2012 data on fluoride levels in drinking water, 2012/13 Quality Outcomes Framework (QOF) diagnosed hypothyroidism prevalence data, 2013 General Practitioner (GP) registered patient numbers, and 2012 practice level Index of Multiple Deprivation scores. We found a positive association between fluoride levels and hypothyroidism. High hypothyroidism prevalence was found to be at least 30% more likely in practices located in areas with fluoride levels in excess of 0.3mg/L. This population study supports earlier hypotheses that fluoride is associated with hypothyroidism. In the UK water is fluoridated at 1ppm (1mg/L) and in areas where water is fluoridated the model predicts that after controlling for other factors, practice populations are significantly more likely to have higher levels of hypothyroidism than those in non-fluoridated areas. Higher levels of fluoride in drinking water, therefore, provide a useful contribution for predicting prevalence of hypothyroidism. For example in contrasting two urban areas we found that practices located in the West Midlands (a wholly fluoridated area) are nearly twice as likely to report high hypothyroidism prevalence in comparison to Greater Manchester (non-fluoridated area).
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MedicalResearch.com Interview with:
Prof. Peter Nordström
Department of Community Medicine and Rehabilitation
Geriatrics, Umeå University
Umeå, Sweden
MedicalResearch: What is the background for this study?...
MedicalResearch.com Interview with:
Samuel D. Pimentel
Doctoral student Statistics Department
Wharton School of the University of Pennsylvania
MedicalResearch: What is the background for this study? What are the main findings?Response: Surgical training has undergone major changes in recent years – including a reduction of six to twelve months of training time – and there is controversy about whether these changes have been good or bad for patient outcomes. Our work partially addresses the issue by asking whether newly-trained surgeons perform better or worse than experienced surgeons. We compared surgical patients treated by new surgeons to a similar group of patients treated by experienced surgeons using a new statistical technique called large, sparse optimal matching. Our analysis found no significant differences in mortality rates between the two groups.
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MedicalResearch.com Interview with:William E. Evans, Pharm.D.
Member, Pharmaceutical Sciences
St. Jude Children’s Research Hospital
MedicalResearch: What is the background for this study? What are the main findings?Dr. Evans: We are currently curing over 85 percent of children with acute lymphoblastic leukemia (ALL), the most common cancer in children. While we continue to focus on pushing cure rates closer to 100 percent through the development of new treatments, we are also increasingly focused on reducing the acute and chronic side effects of treatment. This is important to improve the quality of life for patients during treatment and as they become adults after being cured, because some side effects can persist for decades after treatment is completed.
One of the medications that every child with acute lymphoblastic leukemia received 30-40 times during their 2+ years of treatment is vincristine. The major side effect of vincristine is peripheral neuropathy (about 25 percent of patients develop this side effect), which can cause loss of sensation, numbness, neuropathic pain and alter their motor skills including manual dexterity, balance and ability to walk properly. This can have very practical consequences, such as writing, using a smart phone, and the use of eating utensils. It can also alter their gait.
Our main finding is we discovered that an inherited variant of the CEP72 gene enhanced the risk and severity of vincristine neuropathy in two groups of patients we studied. Those children who inherited two copies of the high-risk CEP72 gene (one from each parent, about 16 percent of patients) had a significantly higher likelihood (about 3.5-fold) of developing vincristine neuropathy and had a more severe form of neuropathy (about 2.5-fold higher severity).
The CEP72 gene encodes a protein essential for normal microtubule formation in cells—a critical process for cell division. Vincristine inhibits this same cellular process. The inherited form of CEP72 that increases the risk and severity of vincristine neuropathy is associated with lower expression of the CEP72 protein. When coupled with vincristine treatment, CEP72 increases a cell’s sensitivity to vincristine. We were able to reproduce this in the laboratory by lowering CEP72 expression in human neurons made from induced pluripotent stem cells and in human leukemia cells, increasing the sensitivity of both to vincristine. We also showed that the leukemia cells from patients who inherited two copies of the CEP72 risk allele were more sensitive to vincristine, suggesting it may be possible to treat these patients with a lower dose of vincristine to reduce their neuropathy without compromising the treatment of their leukemia—a possibility we plan to test in our next clinical trial at St. Jude.
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MedicalResearch.com Interview with:Andrew Paul DeFilippis, MD, MSc
Assistant Professor of Medicine University of Louisville
Director, Cardiovascular Disease Prevention
Medical Director, Cardiovascular Intensive Care Unit
Adjunct Assistant Professor of Medicine Johns Hopkins
University of Louisville Jewish Hospital Rudd Heart & Lung Center
Louisville, KY
Michael Joseph Blaha, MD MPH
Director of Clinical Research
Ciccarone Center for the Prevention of Heart Disease
Assistant Professor of Medicine
John Hopkins
MedicalResearch: What is the background for this study? Response:Atherosclerotic cardiovascular disease is the leading cause of death worldwide. While multiple therapies are available to prevent this common disease, accurate risk assessment is essential to effectively balance the risks and benefits of therapy in primary prevention. For more than a decade, national guidelines have recommended the use of an objective risk assessment tool based on the Framingham Risk Score (FRS) to guide therapy in primary prevention. Recently, the American Heart Association (AHA) and the American College of Cardiology (ACC) developed a new risk score to guide cardiovascular risk-reducing therapy.
We had two main objectives in our study:
1) To compare the performance of the new AHA-ACC risk score with four other commonly used risk scores in a MODERN DAY gender balanced multi-ethnic population.
2) To explore how the use of modern day preventive therapy (aspirin, statins, BP meds and revascularization) impact the performance of the AHA-ACC score.
MedicalResearch: What are the main findings?Response:We found that the new AHA-ACC atherosclerotic cardiovascular disease (ASCVD) risk score and three Framingham-based risk scores, all derived from cohorts’ decade’s old, overestimated cardiovascular events by 25 – 115%, while the Reynolds Risk score, derived from more modern cohorts, accurately predicted the overall event rate in a modern, multi-ethnic cohort free of baseline clinical cardiovascular disease. Overestimation was noted throughout the continuum of risk and does not appear to be secondary to missed events or use of preventive therapies.
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MedicalResearch.com Interview
Professor Nick Franks
Professor of Biophysics and Anaesthetics
Professor William Wisden,
Chair in Molecular Neuroscience
Department of Life sciences
Wolfson Laboratories, Imperial College, South Kensington London
Medical Research: What is the background for this study? What are the main findings?
Profs. Franks and Wisden: We were interested in finding out how a particular type of sedative drug, dexmedetomidine, works in the brain. This drug is increasingly used during intensive care for sedation of patients, but unlike other powerful sedatives, it induces a state whereby the patient can be temporarily woken up. This is a highly useful property because it means patients can be both sedated and responsive during procedures. The drugged sedative state induced by dexmedetomidine struck us as being highly similar to the deep sleep that we all need to have if we have been extensively sleep deprived. If people and animals are kept awake for extended periods of time, they have to sleep. Most people know this from common experience - catching up on lost sleep. But how and why we need to sleep after sleep deprivation is not known. We found that dexmedetomidine-induced sedation and this recovery sleep used the same brain circuits, in a tiny area at the base of the brain called the preoptic hypothalamus. To do this we used a new genetic technique in mice that allowed us to mark or "tag" which neurons in the mouse’s brain were active during sedation or recovery sleep after sleep deprivation. The beauty of this technique is that we could then specifically reactivate these same neurons several days later with a special molecule that only binds to the tagged neurons. This reactivation caused the mice to go into a deep sleep. We concluded that the sedative drug dexmedetomidine copies or hijacks the mechanism used by the brain to respond to sleep deprivation and trigger deep sleep.
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MedicalResearch.com Interview with:
Professor Kathy Cottingham PhD
Departmental of Biological Sciences
Dartmouth University Hanover, NH
Medical Research: What is the background for this study? What are the main findings?
Professor Cottingham: Arsenic is a naturally occurring element that occurs in high concentrations in groundwater in certain parts of the world, including here in New Hampshire. Exposure to high concentrations of arsenic in water has a number of potential health consequences, including cancer, cardiovascular disease, diabetes, obesity, adverse birth outcomes, and altered immune systems. Effects of lower-dose exposures are still under investigation, but emerging evidence suggests similar effects as higher doses.
In the U.S., public drinking water sources are regulated to have arsenic below a maximum contaminant level of 10 micrograms of arsenic per liter of water. However, private wells are not regulated, and there is no requirement to test water in private wells to ensure that the water is safe to drink.
The New Hampshire Birth Cohort, led by Dr. Margaret Karagas, is an ongoing longitudinal study of pregnant women who drink water from private wells. This study quantified arsenic exposure in 72 infants born to women in the cohort, using urine samples and exposure modeling.
Our results show that in general, exposure to arsenic during early infancy is quite low, regardless of how the infants were fed (breast milk vs. formula).
However, a few formula-fed infants were highly exposed to arsenic, likely due to high concentrations of arsenic in the drinking water used to mix their powdered formula.
Arsenic concentrations in breast milk - and in the urine of infants fed only with breast milk - were very low.
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MedicalResearch.com Interview with:
David Mithun, M.D.
Division of Pulmonary and Critical Care Medicine
Mayo Clinic, Rochester, Minnesota
Medical Research: What is the background for this study?
Dr. Mithun: Lung cancer screening should be pursued for those people at highest risk who are otherwise in good enough health to be able to undergo curative intent treatment if cancer is found. The current criteria for screening recommended by the US Preventive Services Task Force of age 55-80 years, 30 pack-years of smoking, and if quit, have done so within 15 years and are based on the National Lung Screening Study (NLST).
Medical Research: What are the main findings?Dr. Mithun: Our data was retrospective over a 28 year time period and showed that an increasing number of people who actually got cancer would not have been candidates for screening based on the current criteria. This suggests there may be some degree of mismatch between risk as defined by the current criteria to screen and those who developed cancer. An increasing number of those who would not have been candidates for screening yet got lung cancer were among those who quit smoking 15 years or longer.
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MedicalResearch.com Interview with:
Peter Storz, Ph.D.
Associate Professor & Consultant Department of Cancer Biology
Mayo Clinic
Jacksonville, FL 32224
Medical Research: What is the background for this study? What are the main findings?
Dr. Storz: Our study focuses on cellular signaling mechanisms that lead to the initiation of pancreatic cancer. After acquisition of an oncogenic mutation of Kras, pancreatic acinar cells can undergo a transdifferentiation process to a phenotype that gives rise to pancreatic intraepithelial lesions (PanINs). These lesions then can further progress to pancreatic cancer.
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MedicalResearch.com Interview with:
Dr. Rebecca E. Amariglio Ph.D.
Massachusetts Alzheimers Disease Research CenterMassachusetts General Hospital
Medical Research: What is the background for this study? What are the main findings?Dr. Amariglio: As the field of Alzheimer’s disease moves towards early detection and treatment, new tests that can measure very subtle changes in cognitive functioning are needed. A new instrument developed by the Alzheimer’s Disease Cooperative Study that measures subjective report of memory changes of both the study participant and a study partner (usually a family member) was associated with cognitive decline over four years. Specifically, greater report of memory concerns was associated with worse memory performance over time.
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MedicalResearch.com Interview with:
Jari Laukkanen Cardiologist, MD, PhD
Institute of Public Health and Clinical Nutrition
University of Eastern Finland
Kuopio, Finland
Medical Research: What is the background for this study? What are the main findings?Dr. Laukkanen: We have been studying many risk factors for cardiovascular disease (CVD) in the general population, and especially exploring protective factors of sudden cardiac death. In our qualified and well defined data on the KIHD prospective study, there were also many questionnaires about other health habits such as the use of sauna (how much, how often, temperature and so on). It was very logical to investigate further sauna use and the risk sudden cardiac death/CVDSs, because sauna is a part of our culture here in Finland. In this country, we have tradition to trust, that its healthy habit, although there are not previous studies showing the value of sauna in the prevention of cardiovascular disease. So we have to study this kind of health habit and CVVs in Finland based on our common traditions...
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MedicalResearch.com Interview with:
Dr. Wei Zheng, MD, PhDDivision of Epidemiology, Department of Medicine,
Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center,
Vanderbilt University School of Medicine, Nashville, TennesseeMedical Research: What is the background for this study? What are the main findings?
Dr. Wei Zheng: Substantial progress has been made in the diagnosis and treatment of cancer, resulting in a steady improvement in cancer survival. However, the degree of improvement by age, race and sex remains unclear. We quantified the differences in the improvement of cancer survival by race, age, and sex over the last two decades.
We used cancer diagnosis and follow-up data from more than 1 million cancer patients, collected in nine SEER registries, to investigate trends in improved survival for seven major cancers in the United States by age, race, and sex between 1990 and 2010. We found that elderly patients experienced a smaller improvement in survival for cancers of the colon/rectum, breast, prostate, lung, and liver than their younger counterparts. In particular, the age-related disparities were most pronounced for those cancers with the greatest advancements in diagnosis and treatment over the past two decades, including cancers of colon/rectum, breast and prostate. African Americans experienced poorer survival than whites for all cancers. Because of a greater improvement in prostate cancer survival in African Americans than for whites, the racial difference in the survival of this cancer decreased during the study period. For ovarian cancer, however, the survival rate declined in African Americans but slightly increased in whites, leading to a wider racial gap in the survival of this deadly cancer. No apparent disparities in survival improvement by sex were noted.
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MedicalResearch.com Interview with:
Maki Yamamoto MD
Health Sciences Clinical Assistant Professor
UC Irvine Health
University of California, Irvine
Orange, CA 92868
Medical Research: What is the...
MedicalResearch.com Interview with: Matthew Buman PhD Asst Professor
SNHP Exercise & Wellness
Arizona State University
Medical Research: What is the background for this study? What are the main findings?
Dr. Buman: A lack of physical activity is a known risk factor for insomnia, poor sleep, and obstructive sleep apnea. In addition to physical activity, sedentary behavior has emerged as an important behavior. Sedentary behavior is not just the lack of physical activity, but actually refers to the time someone spend sitting. This behavior has been shown to, independent of physical activity, be related to many poor health outcomes including cardiovascular disease, diabetes, and even premature death. This is the first study to examine whether there is a relationship between excess sitting and insomnia, poor sleep, and risk for obstructive sleep apnea.
We found, after adjusting for physical activity and body weight (among other confounding factors), that total daily sitting was associated with poor sleep quality but not other sleep metrics or OSA risk. However, we also examined sitting while watching television and found a significant relationship between this type of sitting and a host of sleep quality metrics as well as risk for OSA. In a subsequent analysis we found that despite the independent relationship between sitting while watching television with OSA risk, those that were physically active were protected from this negative impact.
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MedicalResearch.com Interview with:
Iman Osman, MD
Professor, Departments of Dermatology, Medicine and Urology
Associate Director
The Laura and Isaac Perlmutter Cancer Center
Director, Interdisciplinary Melanoma Program
New York University Langone Medical Center
New York, NY 10016
MedicalResearch: What is the background for this study? What are the main findings?Dr. Osman: We were interested in exploring molecules that could be biomarkers or functional regulators of metastasis in melanoma in early-stage tumor lesions on the skin. Though these tumors are treated largely the same (by surgical removal ), patients with these tumors have vastly different outcomes (apparent cure vs. metastatic spread of the disease). The reasons for these disparities are unclear and we have little ability to identify or predict the patients that will be cured and those that won’t. We also don’t have much data to know even if these tumors have differences at the molecular level. Our findings indicate that there are molecular differences in these tumors and that some of these differences contribute to tumor spread. (more…)
MedicalResearch.com Interview with:
Jennifer L. Cook, MD FAHA
Assistant Professor of Medicine | Heart Failure and Transplantation
Medical Director Left Ventricular Assist Device Program
Medical University of South Carolina
Charleston, SC 29425
Medical Research: What is the background for this study? What are the main findings?
Dr. Cook: Although the incidence of heart failure is similar in men and women, women are more likely to die from it. Despite this fact a common misperception persists that men are at greater risk. Although advanced therapies such as mechanical support are as effective in women as in men, women are less likely to receive mechanical support. In clinical trials investigating mechanical support as a bridge to transplant less than 30% of patients were women. In trials investigating mechanical support for patients ineligible for heart transplant even fewer were women, less than 20%. .
Medical Research: What should clinicians and patients take away from your report?Dr. Cook: It has been shown that women with heart failure are more likely to remain under the care of a primary physician instead of being referred for specialized cardiovascular care. The explanation for this pattern is not understood. It is important to raise awareness and emphasize the high risk of heart failure mortality among women.
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MedicalResearch.com Interview with:Dr. Bill Hesselmar
University of Gothenburg
Sweden
MedicalResearch:What is the background for this study? What are the main findings?Dr. Hesselmar: The hygiene hypothesis is the background for this study, and the hypothesis states that children’s immune system need to be stimulated by bacteria and microbes to mature in a proper way prevent the children from developing immune mediated diseases such as allergies. There are increasing support for the hygiene hypothesis, with less allergies found in children from milieus with a rich microbial exposure such as: growing up on a farm or in a developing country, in children with many siblings, and after vaginal delivery as compared to caesarean section. Even though these findings are interesting from a theoretical point of view, they can’t be use in primary prevention since you can’t recommend anyone to live by a farm. We are investigating if there are harmless “microbial sources” in different daily life-situations that are good enough to stimulate children’s immune system. So far we have observed two such possible sources, the sharing of children’s pacifier (Pediatrics 2013) and hand dishwashing (this study). These are, however, only observational data – we have only found an association between hand dishwashing and a lower risk of allergy, we don’t know for sure that the lower risk of allergy was just because of the hand dishwashing. So far we regard it as an “interesting observation”, which need to be confirmed in new studies before any general conclusions could be made.
The main findings was a lower risk of allergy (Odds Ratio 0,57) in children from hand dishwashing families as compared to children from families who use machine dishwashing. (more…)
MedicalResearch.com Interview with:
Claire Duvernoy, MD
Chief, Cardiology Section
VA Ann Arbor Healthcare System
Professor of Medicine
University of Michigan Health System Ann Arbor, MI
MedicalResearch: What is the background for this study? What are the main findings?Dr. Duvernoy: We wanted to look at the indications and outcomes for women veterans undergoing cardiac catheterization procedures as compared with men veterans, given that we know that there are significant gender differences in the non-veteran population between women and men undergoing cardiac catheterization.
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MedicalResearch.com Interview with:
Daniel G. Hackam, MD, PhD, FRCPC
Division of Clinical Pharmacology, Department of Medicine
Western University, London, Ontario, Canada.
MedicalResearch: What is...
MedicalResearch.com Interview with:
Chwee Teck (C.T.) LIM PhD
Provost’s Chair Professor, Deputy Head, Department of Biomedical Engineering & Department of Mechanical Engineering
Principal Investigator, Mechanobiology Institute
Faculty Fellow, Singapore-MIT Alliance for Research & Technology (SMART) National University of Singapore
Medical Research: What is the background for this study? What are the main findings?
Professor Chwee Teck Lim: Epithelial cells have a natural tendency to close gaps and this feature plays a crucial role in many biological processes such as embryological development and wound healing. For example, skin does consist of epithelial cells that when wounded, will elicit closure to initiate healing. How epithelial cells close such gaps has always fascinated researchers from across many disciplines. It is generally accepted that two major mechanisms exist that underlie such a closure. The first is a "cell-crawling" mechanism wherein cells at the edge of the gap actively send protrusions or lamellipodia and use them as footholds to migrate over the gap. However, such a migration requires that the gap is conducive for cells to attach and form adhesions or footholds. The second mechanism is based on a coordinated contraction of multiple bundles of cellular cytoskeletal components (bundles of actin) in a manner similar to that of a "purse-string".
Despite many studies, it has always been difficult to understand and characterize these processes separately since most often they co-exist. In this study, we show that keratinocyte monolayers have a tendency to close circular non-adhesive gaps (gaps that have been coated with a polymer that does not allow cells to adhere or form foot-holds) through contraction of bundles of actin within cells at the edge of the gap. We find that such as closure is strongly affected by the size of the gap (gaps more than 150 um in diameter have a tendency to close only partially), curvature of the gap (gaps with high curvature show better closure), and strength of intercellular adhesion (poor intercellular adhesion completely inhibits closure of non-adhesive gaps).
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MedicalResearch.com Interview with:
Dr. Vasileios Zikos
Assistant Professor
Research Institute for Policy Evaluation and Design (RIPED) and School of Economics
University of the Thai Chamber of Commerce (UTCC)
Bangkok, Thailand
Medical Research: What is the background for this study? What are the main findings?Dr. Zikos: Economic studies that look at subjective well-being typically focus on how and why life circumstances affect an individual’s life satisfaction. While such studies provide valuable insights on the average effects of life changes, they often find substantial variability in the way individuals react to life events. In this study we take a step toward identifying sources of individual heterogeneity by focusing on the link between physical or mental illnesses and health satisfaction and asking whether gender and personality can explain how people cope with becoming ill.
Earlier studies in psychology suggest that personality traits might be relevant to health and health-related behaviors. This allows us to hypothesize what could be the specific role of personality traits when people confront being ill. Our study is based on data collected in the British Household Panel Survey, a national longitudinal data set from the United Kingdom. The survey asked people about their happiness and satisfaction with aspects of their life. It also asked about their physical and mental health and about their personalities, among other things. Our study separates people into three groups: with physical illness only, with mental illness only and with both physical and mental types of illness. Because earlier studies found evidence of personality differences between genders, we conduct our analysis separately for men and women.
We found that illness implies a strong negative effect on the individual’s health satisfaction. Men are less affected by a single-symptom illness than women, but are more affected when more than one symptom is present. The number of symptoms doesn’t change how women are affected. Moreover, women with one of two distinct personality types are less affected by mental illness than all other personality types. The first personality type, high levels of agreeableness, experience high quality relationships in their lives. The second type, women with low levels of conscientiousness, have little need for achievement, order or persistence. For men, however, we did not find statistical evidence that personality affects how they cope with illness.
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MedicalResearch.com Interview with:
Andrew L. Mason MBBS MRCPI
Professor of Medicine,
Senior Scholar, Alberta Heritage Foundation for Medical Research
Director, The Applied Genomic Core,
Division of Gastroenterology and Hepatology
University of Alberta, Edmonton
Medical Research: What is the background for this study? What are the main findings?
Response: The study of viruses resembling mouse mammmary tumour virus (MMTV) dates back to the 1970s when virus like particles were discovered in breast milk of breast cancer patients. The virus was detected at low levels and ultimately researchers met a stalemate by the 1980s because no one could prove the existence of this agent. Interest waned in the study of betaretroviruses in humans when HIV was discovered in the 1980s.
We first found a similar agent in patients with primary biliary cirrhosis, an autoimmune liver disease in 2003. History repeated itself in as much as others could not find the virus and challenged us to show that a significant amount of patients had evidence of proviral integrations into the human genome, the gold standard for providing proof of retroviral infection. This we achieved by isolating biliary epithelium from patients undergoing liver transplantation and then investigating the presence of betaretrovirus proviral integrations in DNA extracted from liver, lymph nodes and biliary epithelial cells using a ligation mediated PCR technique coupled with next generation sequencing. The majority of patients with primary biliary cirrhosis had viral integration and RNA detected in their biliary epithelium, the site of disease and lymph nodes; however, the virus was difficult to detect in whole liver, reflecting the problem with prior studies.
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MedicalResearch.com Interview with:
Douglas E. Brash, PhD
Professor of Therapeutic Radiology and Dermatology
Yale School of Medicine New Haven, CT
MedicalResearch: What is the background for this study? What are the main findings?Dr. Brash: We wanted to know whether the origin of melanoma differed from other cancers because of the melanin. It has long been known that blondes and redheads are sensitive to sunlight, but the prevailing view was that this was because their skin is light. But there are light-skinned, dark-haired people in countries near the equator and they don't have the high skin cancer incidence seen in Australia. Several labs, including ours, had irradiated cells or mice with UV and found more cell death in cells containing melanin than cells lacking melanin. In the last couple of years, two papers have focused attention on the issue; one study found that irradiating mice with UVA only gave melanomas if the skin contained melanin and the other study found that mice genetically predisposed to UV-induced melanoma developed melanomas even without UV if they also had red melanin.
The most important findings are:
First, our skin continues to be damaged by sunlight even when we're out of the sun.
Second, the melanin pigment in your skin is bad for you as well as good: it may be carcinogenic as well as protective.
Third, the chemistry underlying these events, chemical excitation of electrons, has not been seen in mammals before. (more…)
MedicalResearch.com Interview with:
Almudena Zapatero MD PhD
Senior Consultant Dpt Radiation Oncology
Instituto Investigación Sanitaria IIS-IP
Hospital Universitario de la Princesa
Madrid
Medical Research: What is the background for this study? What are the main findings?
Dr. Zapatero: There is a significant body of evidence from randomized trials showing a significant improvement in clinical outcome with the combination of androgen deprivation and conventional-dose radiotherapy (≤70 Gy) in patients with high-risk and intermediate-risk prostate cancer. However, the optimal duration the optimum duration of androgen deprivation in the setting of high-dose radiotherapy remained to be determined.
The results of our trial (DART01/05) show that 2 years of adjuvant androgen deprivation is superior to 4 months androgen deprivation when combined with plus high-dose radiotherapy in terms of biochemical control, freedom from metastasis and overall survival, particularly in patients with high-risk prostate cancer.
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MedicalResearch.com Interview with:
Dr. Y. EltahirUniversity Medical Centre Groningen
Department of Plastic SurgeryGroningen, The Netherlands
Medical Research: What is the background for this study? What are the main findings?
Dr. Eltahir: There are different options for breast reconstruction. They are divided into two main groups; autologous or implant breast reconstructions. all may have their effect on the quality of life and might have surgical complications. We were interested to know which breast reconstruction method may provide a better quality of life. However, we wanted to know this information from the patients point of view, that’s why we used the Breast-Q which is a case specific instrument, to compare the two groups.
We found out that women with autologous breast reconstruction were more satisfied their breast than the implant group. However, this group has more secondary corrections than the control group. Further were no differences between the two groups.
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