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Victor Smida

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2199

Burmese python, one of the largest snakes in the world, could hold the secret for new treatments that could prevent or combat human heart disease, U.S. researchers announced, in a study published Thursday in Science, informs AFP .

This reptile, which can measure up to nine meters in length and reach a weight of 90 pounds, able to swallow a deer or an alligator, secret fatty acids whose properties seem to be true miracles of the heart, say researchers University of Colorado at Boulder, the authors conducted on this species of pythons and rats.

According to scientists, the quantities of triglycerides – the main element in the structure of natural fats and oils – were over 50 times higher in blood python, a day after they swallow their prey.

Despite strong growth in body fat level of these snakes, the study authors found no fat deposits in the heart.

In addition, scientists have measured increasing the amount of certain enzymes, called superoxide dismutase, known for her powerful protective effect on heart muscle, including humans.

Once you have determined the chemical composition of blood plasma (fluid component of blood) to python, during digestion, U.S. scientists injected the liquid or a similar substance taken from pythons that had an empty stomach.

After these injections, snakes monitored an increase in cardiac muscle and signs of good cardiac health. The researchers repeated the experiment and the mice and found the same beneficial effects in rodent heart.

“We found that a combination of fatty acids can have beneficial effects on cardiac growth in living organisms,” said Cecilia Riquelme, lead author of the study.

“Now, try to understand the molecular mechanism behind the process and hope that our results will lead to new therapies capable of providing better treatment for human cardiovascular disease,” said Cecilia Riquelme.

 

2173

Pap Tests Showing A Higher Predictive Value for Endometrial Cancer

American researchers       reveal that Pap tests can detect endometrial cancer, especially endometrial adenocarcinoma, with a  75.8% positive predictive value. They sustain that if Pap smear is showing some obvious malignant cytologic features for endometrial cancer, the pathologist should provide a diagnosis of positive or suspicious, instead of atypical, because this distinction in diagnosis could provide a more sensitive information to the clinicians and they can fallow their patients very carefully. If Pap smear is revealing a false positive result, then the patients could benefit from a proper management.

The Bethesda System 2001 does not recommend the subclassification of atypical endometrial cells because a lack of well-defined criteria. However, researchers at Henry Ford Hospital in Detroit, Michigan, have pushed that envelope a bit.

“Our division advocates that if a Pap smear shows obviously malignant cytologic features of endometrial adenocarcinoma, we should provide the diagnosis of positive/suspicious instead of atypical. This distinction could provide clinicians with much more sensible information in terms of how they follow their patients. Although this may carry some false positive results, the patients may benefit from proper management in a timely manner,” presenter Linda Szymanski, DO, pathology resident at Henry Ford Hospital, told Medscape Medical News.

This study was undertaken to determine the value of the Pap test in detecting endometrial pathology and the potential pitfalls of a false positive diagnosis.

The researchers conducted a retrospective analysis of 153 patients with a diagnosis suspicious or positive for endometrial adenocarcinoma from 2005 to 2011. All selected cases were followed up surgically.

Diagnostic criteria were based on nuclear size, nuclear irregularity, chromatin pattern, presence of nucleoli, cytoplasmic vacuolization, and tumor diathesis.

In all, 132 cases (age range, 25 to 95 years) had significant pathologic findings: 116 cases of endometrial adenocarcinoma, 14 cases of endometrial hyperplasia, and 2 cases of benign endometrial polyp. There were 21 negative pathology findings (age range, 43 to 83 years).

A second review of the 21 false-positive cases and the 2 benign endometrial polyp cases revealed nuclear hyperchromasia, nucleoli, and cytoplasmic vacuolation, but there was no significant nuclear enlargement or tumor diathesis. Overall, the high-yield cytologic criteria generated a 75.8% PPV for detecting endometrial adenocarcinoma (including all positive and suspicious diagnoses).

“When we eliminated the suspicious diagnosis, we achieved a PPV for outright positive diagnosis of 90%,” said Dr. Szymanski. Despite this success, the researchers say that the Pap test is not an effective screening test for endometrial pathology.

“We learned that when there is a lack of significant nuclear enlargement, we should take a step back. A diagnosis of ‘atypical endometrial cells present’ may be more appropriate than a ‘suspicious or positive’

1844

Avastin Improves Chemo for Refractory HER2-Negative Breast Cancer

In cases of refractory HER2-negative breast cancer, adding bevacizumab (Avastin) to common chemotherapies improves progression-free survival, randomized trial data show.

The data are from the RIBBON-2 trial, conducted in women who needed second-line chemotherapy for metastatic breast cancer. Adding bevacizumab to their chemo did not improve their overall survival, as was originally reported several years ago.

But for women with human epidermal growth factor receptor (HER)-2-negative metastatic disease, bevacizumab delayed disease progression and so might still “expand the treatment options,” said lead investigator Dr. Adam M. Brufsky of the University of Pittsburgh in an email to Reuters Health.

In an October 11th online paper in the Journal of Clinical Oncology, Dr. Brufsky and colleagues reported on 684 women who had previously received at least one cytotoxic treatment for local or distant spread of their HER2-negative tumors.

In RIBBON-2 they each received either a capecitabine-, taxane-, gemcitabine-, or vinorelbine-based chemotherapy regimen, and in addition the researchers randomly assigned them 2:1 to receive bevacizumab or placebo.

Median progression-free survival was 7.2 months in the bevacizumab group and 5.1 months in placebo patients, a significant difference. The objective response rate was also better with bevacizumab, although not significantly so (39.5% vs 29.6%).

One year survival rates were similar in the two arms of the study (69.5% vs 66.2%).

The proportion of women who withdrew from the study due to adverse effects was nearly twice as high in the intervention group (13.3% vs 7.2%). Serious adverse events were also more common with bevacizumab (24.5% vs 17.6%). However, there was no difference in the number of treatment-emergent deaths due to adverse events. The most common cause of death was disease progression.

“Taken together,” the investigators conclude, “these data provide a rationale for adding bevacizumab to second-line cytotoxic therapy for patients with HER2-negative metastatic breast cancer.”

Bevacizumab, however, has had trouble retaining its approval for metastatic breast cancer in the US.

http://www.medscape.com/viewarticle/752841

Bevacizumab initially received accelerated approval in 2008, but its efficacy was questioned and follow-up has not shown a survival improvement. In June of this year a U.S. Food and Drug Administration advisory panel ruled against use of the drug, which reportedly costs about $88,000 per patient per year.

Genentech, which makes the drug for Roche, has appealed and a final decision is expected from the FDA later this year.

Meanwhile, insurers in the U.S., among them Blue Shield of California, have stopped routinely covering new prescriptions for breast cancer patients.

In Europe too, there has been less controversy. Bevacizumab was approved there for use in combination with paclitaxel in 2007. Earlier this year European regulators reversed a previous decision and expanded its use to include administration in combination with capecitabine.

Doctors themselves are divided on the agent, with about 40% of those who responded to a small survey saying that they would continue to use the drug even if the FDA finally rejects it (see Reuters Health report of October 26, 2011).

The study by Dr. Brufsky and colleagues was supported by Genentech of South San Francisco, California. Dr. Brufsky acted in an advisory or consultant capacity but received no compensation from the company. A number of other authors received research funding or are employed by Genentech.

3410

Our Brains Are Mathematical Geniuses

According to Thomas Albright, the director of the Vision Center Laboratory from the Salk Institute, in California, the remote place retreat used by so many people in order to “turn off” their brains is in fact not what it seems. Albright, an expert in the functionality of the visual system explains that the change of scenery makes the brain assess the new information that it receives from the environment.  This includes the assessment of objects, movement and other spatial and temporal properties that the new scenery has.

Sergei Gepshtein, one of the researchers involved in the new study, says that in order to assess these new properties, the brain, can only use a limited amount of neurons. Questions arose around the mechanism that allows the brain to use a limited amount of neurons in an effective way. The research team, consisting of Albright, Gepshtein and Luis Lesmes, a scientist from the Schepens Eye Research Institute, published their new paper in the latest issue of the journal Proceedings of the National Academy of Sciences.

Champagne and Cognitive HealthThe expectations of several researchers haven’t been met in their own previous studies. Thus, the premise that a prolonged exposure to a new scenery would mean that the brain would be capable of detecting the most subtle details was disproved. The results obtained in some of the studies are contradictory. These results reveal that there is no correlation between the amount of time spent examining the environment and the amount of details the brain perceives and remembers. According to Albright, the results of the studies have shown four different types of reactions. The prolonged exposure to the environment had no effect for some people, whilst having an important effect on others. However, people also experienced an increased awareness for other details that weren’t subject of the study.

Gepshtein reveals that their study emerged from the asking of a new question, “What happens when you look at the problem of resource allocation from a system’s perspective?”. Due to the fact that the brain has a limited number of neurons that can be assigned to different tasks, only a part of them are used for the assessment of this new scenery. “As a result of allocating resources to a stimulus, you lose sensitivity to other things, which may or may not be familiar”, said Gepshtein. As a conclusion for their new finding, professor Albrigth says that if you want to improve your abilities in one thing, your ability to improve in other domains will diminish.

The published study reveals a mathematical point of view. According to the research team, the computations made by the visual system in order to accomplish the adaptation to a new scenery is very much alike the signal processing method described by Dennis Gabor. He received the Nobel Prize in physics in 1971 for his discovery in the field of signal processing. In their studies, Gabor and other contemporary scientists have shown that the content frequency and location of a signal are interdependent. It’s easy to understand and measure the location of a signal. However, the challenge is to measure its frequency at the same time. This is due to the fact that frequency takes a longer time to be accurately determined. This translates into a compromise: Either you have a precise measurement of the location of the signal, either you get a precise determination of its frequency, but a precise determination of both cannot be accomplished. In 1971, Gabor invented the “Gabor Filter”, which allows for the best measurement for both properties.

According to Gepshtein, the human brain uses a similar method as the Gabor Filter. “In human vision, stimuli are first encoded by neural cells whose response characteristics, called receptive fields, have different sizes”, noted Gepshtein, whilst adding that neural cells with larger receptive fields are more sensitive to the signals with a lower spatial frequency. This acts like a filter in the first stages of the visual pathway. This filter is responsible for the stimuli that are received and the ones that aren’t. A change of scenery leads to a change of filter, thus some of the stimuli that were previously received and analyzed are no longer detected, allowing the reception of other stimuli that were previously undetected. “When you see the entire filter, you discover that the pieces – the gains and losses – add up to a coherent pattern”, concluded Gepshtein. Albright added that this process happens whether or not you are consciously paying attention to the change of scenery. However, the adaptation is not an instantaneous process.

3694

Non-surgical Techniques may cure Barrett’s Esophagus

Researchers at Plymouth University Peninsula Schools of Medicine and Dentistry have made new discoveries about Barrett’s esophagus and gastroesophageal reflux disease. Although many studies have shown that these diseases are acquired conditions, apparently it seems that in fact the two are genetically determined, and that environmental factors contribute to a relatively small extent. The study, published in the leading journal Gastroenterology, indicates that in the future it is possible that Barrett’s esophagus and gastroesophageal reflux disease benefit from other treatments.
Gastroesophageal reflux disease and Barrett’s esophagus are two closely related medical conditions that arise due to the  irritating action of stomach acid in the esophageal lining. Reflux of stomach acid into the esophagus involves a weakening of the esophageal sphincter and this is favored by food, obesity etc. There are certain foods and drinks that can cause the lower esophageal sphincter incontinence such as chocolate, sodas, coffee etc. Obesity is another factor contributing to sphincter incontinence and gastric reflux. There have been studies that have shown that obesity is an important risk factor for Barrett’s esophagus due to increased abdominal pressure.

genetics

Barrett’s esophagus is considered a premalignant condition that is characterized by esophageal cell metaplasia. Generally people most at risk to develop Barrett’s esophagus are those who suffer from indigestion and heartburn long time. Although the risk of malignant transformation of Barrett’s esophagus in esophageal adenocarcinoma is relatively low, however the prognosis of this cancer is bad.

Treatment of Barrett’s esophagus is performed according to the degree of dysplasia and patient’s condition. Patients with Barrett esophagus are generally indicated for endoscopic mucosal resection or esophagectomy. But recent discoveries made on the genetic basis of this condition could result in the development of non-surgical therapies in the future. Up to date  besides mucosal resection and esophagectomy, there are several treatment options for Barrett’s esophagus: radiofrequency ablation, argon plasma coagulation, etc.

Professor Janusz Jankowski, one of the authors from Plymouth University Peninsula Schools of Medicine and Dentistry and Queen Mary University of London, said that recent studies that show that Barrett’s esophagus has a strong genetic determinism make an exciting contribution regarding non-surgical treatment options of this condition. He added that more research should be done until a non-surgical therapy will be available and that people should not ignore advice on diet and lifestyle. “The main success is that, before this, we would never have imagined Barrett’s Oesophagus as having the potential to be an immune-mediated disease in the way conditions such as rheumatoid arthritis, psoriasis and inflammatory bowel disease are “ it emphasises how little we really know,” he said.

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Gut microbiota may be the key for new method to lose weight

Researchers at Harvard in collaboration with Massachusetts General Hospital have made new discoveries that could help fight obesity. It appears that microbiota suffers some changes after gastric bypass surgery and that these microbes can help obese people lose weight faster. The study results, which were published in Science Translational Medicine, are promising but still there must be done more studies in order to replicate the results in humans. Peter Turnbaugh, a Bauer Fellow at Harvard’s Faculty of Arts and Sciences (FAS) Center for Systems Biology, and one of two senior authors of the paper, said that experiments made by them showed that the colonization of mice with altered microbial community led to weight loss by about 20% as much as if they had undergone bypass surgery. In addition, the mice were able to maintain a lower body fat.

Lee Kaplan, director of the Obesity, Metabolism and Nutrition Institute at MGH and the other senior author of the paper, added that their study showed that the specific effects of gastric bypass on microbial flora contributes to the ability to cause weight loss and that this discovery can be manipulated so that it becomes a valuable tool to treat obesity.

The  ability to obtain these effects without surgery would provide a new way to treat obesity and would be a valuable alternative for those who do want to undergo bypass surgery.

Obese

Obese

Turnbaugh said that although the study results were promising, however it will take time until these results are replicated in humans. He also said that this new method should not be seen as an alternative to replace exercise or going to the gym. In fact  every method of weight loss or diet should be accompanied by sports in order to obtain the best results. He added that it would be a big improvement if one day could provide an alternative that has the same effect as gastric bypass.

Previous studies have shown that the digestive tract of mice ( lean as owell as obese mice) is populated by two types of bacteria, Firmicutes and Bacteroidetes. After gastric bypass surgery,  microbial flora consists of other types of bacteria, that is Proteobacteria and Proteobacteria, Firmicutes is found in relatively low amounts. In addition, these changes appear rather quickly after gastric bypass surgery (after about a week) and are stable.

However, researchers wanted to mention that more studies should be done to clarify the exact mechanism by which microbial flora can help weight loss. “We think such studies will allow us to understand how host/microbial interactions in general can influence the outcome of a given diet,” Kaplan said.

3038

Vitamin D may help control glucose level in obese children

A new study led by researchers at the University of Missouri shows that vitamin D supplements can help obese, diabetic patients. It seems that vitamin D can help obese children to control their blood sugar and thus prevent the onset of diabetes. Vitamin D is one of four fat-soluble vitamins (A, D, E, K) and is essential in calcium metabolism in the body. It is well-known that vitamin D is essential for healthy bones, muscles and nerves. Vitamin D is the only vitamin that is formed in the skin by ultraviolet radiation, so vitamin D deficiency is rare. However it is possible a lack of vitamin D be detrimental to obese children.

It is known that in the past 30 years the rate of obesity in the United States has increased dramatically among children and adolescents. Obesity is a risk factor for diabetes, which is characterized by high levels of blood glucose. Catherine Peterson, associate professor of nutrition and year Exercise Physiology at MU, said vitamin D supplements had about the same effect as a hypoglycemic drug. She added that vitamin D supplements decreased the amount of insulin needed, which meant better blood glucose control.

Insulin

Insulin

Researchers made a study involving 35 obese pre-diabetic children and adolescents who received treatment at MU Adolescent Diabetes Obesity Program. All the 35 participants in the study had the same diet and physical activity and insufficient levels of vitamin D. They were randomized to receive either placebo or high-dose vitamin D supplement daily for six months. It seems that those who received an increased dose of vitamin D reduced the amount of insulin that usually took. Peterson said that the dosage of vitamin D that was used in the studies is not recommended to anyone. She said that clinicians should check vitamin D levels in obese patients because it is likely to be low. Increasing the amount of vitamin D may help control blood sugar and obesity that is associated with insulin resistance.

Peterson explained that vitamin D in obesity is not processed properly because it is trapped in adipose tissue and that this means that obese children should take  twice more vitamin D than their peers to maintain an appropriate level. “The vitamin gets stored in their fat tissues, which keeps it from being processed. This means obese individuals need to take in about twice as much vitamin D as their lean peers to maintain sufficient levels of vitamin D,” said Paterson.

2284

Heart defects may be caused by stress during pregnancy, according to study

The latest research reveals that congenital heart defects, some of the most common defects found in newborns, are caused by maternal stress (before and during pregnancy). It seems that maternal stress has consequences on fetal heart development. However, the study results, which were published in the journal Pediatrics, did not show a cause-effect association between maternal stress and congenital heart defects.

Dr. Edward McCabe, senior vice president and medical director of the March of Dimes, said that there are several studies showing an association between heart defects and stress. He said the studies regarding this issue should be continued. Congenital heart defects, some of the most common birth defects in new-borns, include conditions like atrial septal defect, ventricular defect or transposition of vessels. These defects may be surgically resolved after birth if timely discovered and diagnosed by pediatricians. However,  there are situations when these defects do not need surgery or situations when these defects are discovered too late when complications already appeared (pulmonary hypertension or heart failure), and surgery cannot fix them.

Over time there have been incriminated several factors responsible for the occurrence of these congenital heart defects: drugs, alcohol, smoking, radiation, viruses, prematurity. Genetic factors are involved in about 10% of cases of congenital heart defects (Down syndrome, Turner syndrome).

stress during pregnancy

Babies

Now researchers conducted a study in which they analyzed 1.8 one million children born in Denmark from 1978 to 2008 to see if congenital heart defects are due to certain factors. Mothers of these children were under stress before or during pregnancy (they lost a close relative at the time of conception or during pregnancy). It was found that women who suffered from stress before or during pregnancy had a slightly higher risk of giving birth to children with congenital heart defects. Study co-author Dr. Jorn Olsen, professor and chairman of the department of Epidemiology at the School of Public Health at the University of California, Los Angeles, said it is possible that these congenital heart defects run in families and that some members might have died because of those conditions.

Olsen explained that animal studies have shown that maternal stress during pregnancy affects embryonic development. He said that maternal stress may influence diet and this could adversely affect embryonic development. Another explanation could be that stress induces changes in DNA child in the womb. “This and other studies tell us to take care of pregnant women who experience severe stressful events shortly before or while they’re pregnant,” Olsen said.

2558

Reseachers uncover new findings about esophageal cancer

A recent study led by researchers at Dana-Farber Cancer Institute reveals new findings on esophageal adenocarcinoma, a cancer whose incidence has increased dramatically in recent years. The research comes with a possible explanation for this alarming increase in the incidence of esophageal adenocarcinoma.

Statistics show that over the last 30 years the incidence of esophageal cancer increased approximately about 600 times in the United States of America. It is believed that an important risk factor for esophageal adenocarcinoma is gastroesophageal reflux disease. Gastroesophageal reflux disease involves the presence of stomach acid into the esophagus, which damages the lining of the esophagus. This condition can sometimes result in Barrett’s esophagus which is a premalignant condition for esophageal cancer.

Cell

Cell

Adam Bass, MD, of Dana-Farber and the Broad Institute, who is co-senior author of the paper, said that esophageal adenocarcinoma, especially those located at the junction between the esophagus and stomach, was extremely rare 40 years ago but now there are about 15,000 new cases that occur each year in the United States. He pointed out the fact that unfortunately esophageal adenocarcinoma is a cancer with poor prognosis as 5-year survival rate is only 15%. Although the incidence has risen dramatically in recent decades, in terms of treatment there have not been many improvements. Bass explained that the purpose of the study was to find other genetic abnormalities that cause this type of cancer, to find new methods of early diagnosis and more effective treatment.

It is not clear why the incidence of esophageal adenocarcinoma has increased so much in recent years, although there are several assumptions in this regard. It seems that an important factor in the development of this cancer is obesity, especially in men. It seems that obesity causes increased abdominal pressure which causes  lower esophageal sphincter incontinence.

To find out more about the genetic basis of cancer of the esophagus researchers conducted a study in which they analyzed specific sections of DNA from 149 patients with esophageal adenocarcinoma. In addition, in 15 of these patients researchers sequenced the entire genome. Gad Getz, PhD, of the Broad Institute and Massachusetts General Hospital, co-author of the study, said the study revealed a pattern of DNA changes that has never been seen before. These DNA changes are in fact some mutations that occur in esophageal cells and it seems that these mutations are caused by reflux of stomach acid. “Identifying the mutated genes within these tumors will help us understand the underlying biology of the disease,” said Bass.

2231

 Children at higher risk to resistant staph infections during summer

According to a nationwide study led by researchers at the Johns Hopkins University School of Medicine, there is a specific seasonal tendency of resistant staphylococcal infections in adults and children. It seems that children are at greater risk of staphylococcal infections resistant to antibiotics during the summer, while adults have a greater risk in winter. The study is published in the  American Journal of Epidemiology.

Staphylococcus aureus is a Gram-positive bacteria that is normally found on the skin surface, about 25% of adults being carriers of S. aureus. But under certain conditions (immunosuppression, the presence of other systemic diseases), it can produce a series of superficial or deep, systemic or local infections, which sometimes can be fatal. It should be noted that Staphylococcus aureus is one of the most common pathogens involved in hospital infections. It is also worth saying that Staphylococcus releases some toxins, so this bacteria can generate not only infections but also intoxications.

staph infections

staph infections

Regarding this seasonal and age preference of treatment-resistant staphylococcal infections, Eili Klein, Ph.D., lead author on the study and a researcher at the Johns Hopkins Center for Advanced Modeling in the Social, Behavioral and Health Sciences, said they do not yet know why this trend occur. However, he believes that excessive use of antibiotics in winter may be the cause. It seems that the strain that infects adults in winter is usually acquired in hospitals and is more resistant to antibiotics. Summer strain of  MRSA ( methicilin resistant Staphilococcus aureus) that occurs especially in children during the summer is often a germ acquired in the community and resistant to fewer antibiotics.

Klein said that excessive prescribing of antibiotics can have negative effects. Antibiotic is quite common in winter, when the incidence of respiratory infections and the common cold is maximum. But inadequate administration of antibiotics to treat upper tract respiratory infections and colds contribute to the development of resistance. In addition, it is already known that antibiotics has no benefit when given to patients with influenza, because flu is given by a virus and not by a bacterium.

Staphylococcus is responsible for a range of infections such as skin infections (such as folliculitis, cellulitis, furuncle, erysipelas), respiratory tract infections (pneumonia, lung abscess), bone infection (osteomyelitis, arthrytis), etc.. These infections are difficult to treat because  Staphylococcus  is one of the germs that easily develops resistance to antibiotics. However, a targeted treatment applied correctly can cure staph infection.