Author Archives: Astron Lifesciences
Do not take undue stress in life and enjoy better quality, fertile sperm to maximize your chances.
Psychological stress is harmful to sperm and semen quality, affecting its concentration, appearance, and ability to fertilise an egg, a significant study says.
“Men who feel stressed are more likely to have lower concentrations of sperm in their ejaculate. The sperm they have are more likely to be misshapen or have impaired motility,” explained Pam Factor-Litvak, an associate professor of epidemiology at Columbia University’s Mailman school of public health.
Stress may trigger the release of steroid hormones called glucocorticoids, which could blunt levels of testosterone and sperm production.
Another possibility is oxidative stress that has been shown to affect semen quality and fertility.
“Stress has long been identified as having an influence on health. Our research suggests that men’s reproductive health may also be affected by their social environment,” added Teresa Janevic, an assistant professor at Rutgers University’s school of public health.
To understand this, researchers studied 193 men, ages 38 to 49, enrolled in the study of the environment and reproduction at the Kaiser Foundation Health Plan in Oakland, California, between 2005 and 2008.
The men completed tests to measure work and life stress on subjective scale (how they felt overall) and objective scale (life events behind the stress).
Measured subjectively or objectively, life stress degraded semen quality.
Workplace stress was not a factor, however the researchers say it may still affect reproductive health since men with job strain had diminished levels of testosterone.
Unemployed men had sperm of lower quality than employed men regardless of how stressed they were, said the study published online in the journal Fertility and Sterility.
India has an estimated 15-20 million asthmatics and doctors here feel that awareness and early diagnosis play a vital role in containing this chronic respiratory disease that has been surging fast in the last decade.
According to World Health Organisation estimates, between 100-150 million people worldwide suffer from asthma of which 15-20 million belong to India.
As per a WHO report on World Asthma Day today, the fundamental cause of asthma, that is characterised by recurrent attacks of breathlessness and wheezing is not completely understood, but the strongest risk factors for developing asthma include indoor allergens like dust mites in bedding and carpets.
Outdoor allergens that may cause asthma include pollens, tobacco smoke and chemical irritants, it said.
Dr Prahlad Prabhudesai, Chest specialist at Lilavati Hospital here cautioned that there may be some people who do not show qualities like breathlessness but may still be suffering from ‘silent Asthma’, which cannot be prevented as it is a hereditary disorder.
“There is no medicine available to prevent asthma. Only the attacks can be prevented. There are some patients who do not show any qualities of being an asthmatic. People who frequently sneeze or periodically cough may also be asthmatic. They need to get a diagnosis done at the earliest,” he said.
Speaking to PTI, Dr. Vyanketesh Joshi, Chief Trustee of Siddh Dhyan Foundation said that one can have a better chance of controlling asthma if diagnosed early.
“Asthma cannot be cured but it can be controlled. People suffering from asthma can learn to identify and avoid the things that trigger an episode and educate themselves about medication. With proper treatment, people with asthma can have fewer and less severe attacks,” Dr Joshi said.
World Asthma Day is celebrated round the world on the first Tuesday of May. It was first celebrated by Global Initiative For Asthma (GINA) in 1998 after its first ‘World Asthma Meeting’ in 1998. The Day is celebrated in order to raise awareness among public worldwide about the precaution and prevention of this bronchial condition.
The theme of this year concentrates on cause and effects of asthma: ‘You Can Control Your Asthma’.
The scientists at Arizona State University have found a rare atomic level change at the enzyme telomerase that holds secrets as to how we grow old.
The telomerase is a naturally occurring enzyme that maintains telomeres and prevents them from shortening during cell division. Telomeres are found at the ends of human chromosomes and are stretches of DNA which protect the genetic data.
“Telomerase is crucial for telomere maintenance and genome integrity. Mutations that disrupt telomerase function have been linked to numerous human diseases that arise from telomere shortening and genome instability,” explained Julian Chen, a professor of chemistry and biochemistry at Arizona State.
The telomeres keep chromosome ends from fraying and sticking to each other, which would destroy or scramble our genetic information.
“This shortening process is associated with aging, cancer and a higher risk of death,” scientists noted.
“We are particularly excited about this research because it provides, for the first time, an atomic level description of the protein-RNA interaction in the vertebrate telomerase complex,” Chen added.
The scientists in collaboration with the Chinese Academy of Sciences in Shanghai had conducted the crucial research, which will be published in the journal Nature Structural and Molecular Biology.
“We know prolonged use of corticosteroids in the treatment of asthma is a risk factor of osteoporosis, but we have not had definite data showing the relationship between asthma itself and bone loss,” explained Jae-Woo Jung of Seoul National University Medical Research Centre in South Korea.
“This study has shown a meaningful association between the two conditions even in the absence of previous oral corticosteroid use,” Jung added.
For the study, researchers examined more than 7,000 patients, 433 of which had airway hyper-responsiveness (AHR) or asthma.
Lumber spine and femur bone density was significantly lower in those with AHR or asthma, than those without the conditions, showed the findings of the research.
“Reasons can include corticosteroid use, low levels of vitamin D or even race,” said John Oppenheimer, an associate editor of the journal Annals of Allergy, Asthma & Immunology that published the study.
NEW DELHI: The waist size of your child can predict if he or she is likely to suffer from any metabolic disorder. This has been found in a multi-centre cross-sectional study done by the International Diabetes Federation. It was conducted on 10,842 children in Delhi, Chennai, Kolkata, Pune and Raipur.
Dr Archana Dayal Arya, paediatric endocrinologist at Sir Ganga Ram Hospital, New Delhi, and co-author of the study, said Metabolic Syndrome (MS) in children has been defined as the presence of high triglyceride levels in blood, low HDL cholesterol (good cholesterol), increased fasting blood glucose levels, high systolic blood pressure and waist circumference > 75th percentile. It results in increased risk of hypertension, type 2 diabetes mellitus, and atherosclerosis cardiovascular disease.
“It is shocking to see children as young as six years old with diseases like hypertension, diabetes mellitus and abnormalities in the lipid profile,” the doctor said.
The study found that the risk factor for Indian children for developing MS was at 70th waist circumference (WC) percentile, which is significantly lower than international proposed WC cutoff of 90th percentile.
Dr Anuradha Khadilkar, consultant paediatrician in Jehangir Hospital, Pune and corresponding author of the study, said primary or essential hypertension, commonly seen in adults, is becoming common in children, who are obese or overweight.
The study, which will be published in the forthcoming issue of the Journal of Paediatrics, found that 3.3 per cent or 358 children out of a total sample size of 10,842 were hypertensive.
A new study has found that chronic cigarette use affects your posture because it affects the brain systems. Postural instability is pretty common among alcohol dependent (AD) individuals, because alcohol damages that parts of the brain systems that maintain postural stability.
Thomas Paul Schmidt, a research associate in the department of radiology and biomedical imaging at the University of California San Francisco, and San Francisco Veterans Affairs Medical Center, said that anecdotal and empirical findings revealed that postural instabilities with eyes open or closed is common in treatment-seeking AD individuals.
During the study, Schmidt and his colleagues recruited AD participants from substance-abuse outpatient clinics and controls from the local community. To assess postural stability and balance, they administered an ataxia battery to 115 smoking and non-smoking AD individuals and to 74 smoking and non-smoking light/non-drinking controls. The researchers assessed subgroups of AD individuals at three testing sessions during abstinence from alcohol: one week, five weeks, and 34 weeks of abstinence.
They assessed all controls once, and a subset of the non-smoking controls was re-tested after 40 weeks. The researchers then used this data to find out if cigarette smoking affected postural stability in both the control and AD groups, and if postural stability is affected by smoking during alcohol abstinence.
Schmidt remarked that during the research it was revealed that non-smoking AD individuals showed marked improvement on a measure of postural stability over the course of eight months of abstinence.
The study has been published online in the journalism Alcoholism: Clinical and Experimental Research
Anopheles gambiae mosquitoes are the main transmitters of malaria, which affects around 200 million people every year. The females mate only once during their lives.
They store the sperm from this single mating in an organ called the spermatheca, from which they repeatedly take sperm over the course of their lifetime to fertilise the eggs that they lay. The female needs the sperm to stay healthy whilst they are in storage in the spermatheca, so that they are viable each time she uses them to reproduce.
The new research shows that the sperm are partly protected by the actions of an enzyme called HPX15. When the researchers interfered with HPX15 in female A gambiae mosquitoes in the laboratory, the females fertilised fewer eggs and therefore produced fewer offspring. This is the first time that scientists have discovered a mechanism that preserves the function of sperm in A gambiae.
The researchers, from Harvard School of Public Health, the University of Perugia and Imperial College London, believe that their insight could ultimately lead to a new weapon in the fight against malaria. This would work by disabling HPX15 to reduce female fertility and through that, reduce the number of malaria-carrying mosquitoes in circulation.
“Malaria kills over 650,000 people every year and we need to find new ways of tackling it, partly because mosquitoes continue to evolve ways of resisting our efforts,” Dr Robert Shaw, one of the lead authors of the research, said. “We are interested in cutting the numbers of malarial mosquitoes by impairing their ability to reproduce, and our new study suggests a way that we might be able to do this.
“There is no single magic bullet for tackling malaria, but making mosquitoes less fertile could provide us with a valuable weapon against the disease,” said Shaw. The study suggests that HPX15 may protect the stored sperm against potentially damaging molecules called free radicals, which are particularly abundant after a female takes a blood feed.
Ensuring that the sperm are healthy after blood-feeding is important for the female’s fertility as she reproduces after each feed, fertilising her eggs with sperm released from the spermatheca. The study was published in the journal Proceedings of the National Academy of Sciences.
Investigators analyzed 25 genes in postmortem brain tissue of children with and without autism. These included genes that serve as biomarkers for brain cell types in different layers of the cortex, genes implicated in autism and several control genes.
Their findings are published in the online edition of the New England Journal of Medicine.
“Building a baby’s brain during pregnancy involves creating a cortex that contains six layers,” said Eric Courchesne, Ph.D., professor of neurosciences and director of the Autism Center of Excellence at University of California, San Diego (UC San Diego).
“We discovered focal patches of disrupted development of these cortical layers in the majority of children with autism.”
The findings confirm the hypothesis that for some children with autism, the brain can sometimes rewire connections and the child can improve abilities — especially with early therapeutic intervention.
Rich Stoner, Ph.D., of the UC San Diego Autism Center of Excellence created a unique three-dimensional model visualizing brain locations where patches of cortex had failed to develop the normal cell-layering pattern.
“The most surprising finding was the similar early developmental pathology across nearly all of the autistic brains, especially given the diversity of symptoms in patients with autism, as well as the extremely complex genetics behind the disorder,” said Ed S. Lein, Ph.D.
During early brain development, each cortical layer develops its own specific types of brain cells, each with specific patterns of brain connectivity that perform unique and important roles in processing information.
As a brain cell develops into a specific type in a specific layer with specific connections, it acquires a distinct genetic signature or “marker” that can be observed.
The study found that in the brains of children with autism, key genetic markers were absent in brain cells in multiple layers.
“This defect,” Courchesne said, “indicates that the crucial early developmental step of creating six distinct layers with specific types of brain cells — something that begins in prenatal life — had been disrupted.”
“Equally important,” said the scientists, “these early developmental defects were present in focal patches of cortex, suggesting the defect is not uniform throughout the cortex.”
The brain regions most affected by focal patches of absent gene markers were the frontal and the temporal cortex, possibly illuminating why different functional systems are impacted across individuals with the disorder.
The frontal cortex is associated with higher-order brain function, such as complex communication and comprehension of social cues. The temporal cortex is associated with language.
The disruptions of frontal and temporal cortical layers seen in the study may underlie symptoms most often displayed in autistic spectrum disorders. The visual cortex — an area of the brain associated with perception that tends to be spared in autism — displayed no abnormalities.
“The fact that we were able to find these patches is remarkable, given that the cortex is roughly the size of the surface of a basketball, and we only examined pieces of tissue the size of a pencil eraser,” said Lein.
“This suggests that these abnormalities are quite pervasive across the surface of the cortex.”
Researching the origins of autism is challenging because it typically relies upon studying adult brains and attempting to extrapolate backwards.
“In this case,” Lein said, “we were able to study autistic and control cases at a young age, giving us a unique insight into how autism presents in the developing brain.”
“The finding that these defects occur in patches rather than across the entirety of cortex gives hope as well as insight about the nature of autism,” added Courchesne.
According to the scientists, such patchy defects, as opposed to uniform cortical pathology, may help explain why many toddlers with autism show clinical improvement with early treatment and over time.
The findings support the idea that in children with autism the brain can sometimes rewire connections to circumvent early focal defects, raising hope that understanding these patches may eventually open new avenues to explore how that improvement occurs.
Source: University of California, San Diego
Reviewed by John M. Grohol, Psy.D. on April 7, 2014
“This is a welcome discovery whatever the origin,” Mark Hulett from La Trobe Institute for Molecular Science in Melbourne was quoted as saying.
The molecule, found in nicotiana sylvestris (flowering tobacco) plant, forms a pincer-like structure that grips onto lipids present in the membrane of cancer cells.
It then effectively rips them open, causing the cell to expel its contents and explode.
According to researchers, this universal defence process could also potentially be harnessed for the development of antibiotic treatment for microbial infections.
The pre-clinical work is being conducted by the Melbourne biotechnology company Hexima. “The preliminary trials have looked promising,” said Hulett.
The study was published in the journal eLife.