A scan which shows how brain regions interact may help diagnose migraines, depression, bipolar disorder and many other ailments of the brain, scientists say. A study published in the journal Neuron shows that a kind of brain scan called functional connectivity MRI (fcMRI) can reliably detect fundamental differences in how individual brains are wired.
The technique could potentially be used to distinguish healthy people from those with brain diseases or disorders, and provide insight into variations in cognitive ability and personality traits. “This is a step towards realising the clinical promise of functional connectivity MRI,” said Steven Petersen, a professor at the Washington University School of Medicine in the US.
“Before we can develop diagnostic tests based on fcMRI, we need to know what it is actually measuring. We show here that it’s not measuring what you’re thinking, but how your brain is organised. That opens the door to an entire new field of clinical testing,” Petersen said.
Researchers analysed data from more than 10 hours of fcMRI scans on nine people, collected in 10 separate one-hour sessions for each person. During the scans, each person performed tasks related to vision, memory, reading or motor skills, or rested quietly. Functional MRI scans generate a dynamic map of the outer surface of the brain, showing changing hot spots of activity over time. To create a functional connectivity map, postdoctoral researcher Caterina Gratton divided the brain’s surface into 333 regions and identified areas that became active and inactive in unison.
She then constructed brain network maps for each individual, showing patterns of correlation between parts of the brain. The sheer quantity of data available on each person allowed her to analyse how much an individual’s brain networks changed from day to day and with different mental tasks.”Brain networks captured by fcMRI are really about the individual,” Gratton said. “Whether someone’s watching a movie or thinking about her breakfast or moving her hands makes only a small difference. You can still identify that individual by her brain networks with a glance,” she said.
The consistency of the fcMRI scans makes them a promising diagnostic tool, researchers said. Although the technique’s potential to identify brain disorders and diseases was noted years ago, fcMRI-based diagnostic tests have yet to make their way into doctors’ offices. Progress has been stymied by confusion over whether the scans reflect fundamental, stable features of the brain, or if they change with every passing thought. The researchers found that the technique was powerful enough to distinguish people who were extraordinarily alike.
Higher salt intake can cause gastrointestinal bloating, says study
People report more gastrointestinal bloating when they eat a diet high in salt, a study has found.
Researchers at the Johns Hopkins Bloomberg School of Public Health in the US re-analysed data from a large clinical trial conducted two decades ago, and found that high sodium intake increased bloating among trial participants.
“Bloating is one of the leading gastrointestinal complaints in the US and can be exacerbated in some people by a high-fiber diet. Our results suggest that they might be able to reduce that bloating, without compromising on healthy fiber, by lowering their sodium intake,” said Noel Mueller, senior author of the study.
Bloating is estimated to affect up to a third of US adults overall, and more than 90 per cent of those with irritable bowel syndrome, according to the study.
Bloating features a buildup of excess gas in the gut. The production of gas can be attributed to gas-producing gut bacteria breaking down fiber. There is also some evidence that sodium can stimulate bloating.
The study, published in the American Journal of Gastroenterology, is the first to examine sodium as a cause of bloating in the context of low- and high-fiber diets.
The study analysed data from the DASH-Sodium trial, conducted at four clinical centres during 1998-99. It tested the DASH diet, a high-fiber diet which is relatively low in fat and high in fruits, nuts, and vegetables, against a low-fiber control diet.
Each of the two diets was tested at three levels of sodium, and the 412 participants all had high blood pressure at the trial start.
The trial was set up chiefly to determine the effect of dietary sodium and other factors on blood pressure, but included data on participants’ reports of bloating — data that Mueller and his colleagues analysed for the new study.
The team found that prior to the trial, 36.7 per cent of the participants reported bloating, which is more or less in line with national surveys of bloating prevalence.
They found too that the high-fiber DASH diet increased the risk of bloating by about 41 percent, compared to the low-fiber control diet — and men were more susceptible to this effect, compared to women.
But the scientists also determined that sodium was a factor in bloating. When they combined data from the DASH and control diets, and compared the highest level of sodium intake to the lowest, they found that the high-sodium versions of those diets collectively increased the risk of bloating by about 27 per cent compared to the low-sodium versions.
The key implication is that reducing sodium can be an effective way to reduce bloating — and in particular may be able to help people maintain a healthy, high-fiber diet.
Second-hand smoking dangerous:study
A recent study has discovered a link between second-hand smoking and development of chronic kidney disease (CKD).
The study, published in the Clinical Journal of the American Society of Nephrology, found out that exposure to second-hand smoking increases the risk of various diseases and the researchers investigated the link between exposure to second-hand smoking and CKD.
The study included 131,196 never-smokers who participated in the Korean Genome and Epidemiology Study from 2001 to 2014. Participants were classified into 3 groups based on the frequency of second-hand smoke exposure as assessed with survey questionnaires: no-exposure, less than 3 days per week of exposure, and 3 or more days per week of exposure.
Participants with less than three days per week and those with three or more days per week of exposure had 1.48-times and 1.44-times higher odds of having CKD when compared with participants with no second-hand cigarette exposure
“Second-hand smoke exposure at home or in the workplace is still prevalent despite legislative actions prohibiting public smoking.
This exposure was found to be clearly related with CKD, even with less-frequent amounts of second-hand smoke exposure,” said Jung Tak Park, the lead researcher.
Vitamin C may lower BP, sugar levels in diabetics
Taking vitamin C supplements can help diabetics by lowering elevated blood sugar levels throughout the day, a study has found.
The research, published in the journal Diabetes, Obesity and Metabolism, also found that vitamin C lowered blood pressure in people with type 2 diabetes, suggesting benefits for heart health too. According to Glenn Wadley from Deakin University in Australia, the results may help millions currently living with the health condition.
”We found that participants had a significant 36 per cent drop in the blood sugar spike after meals. This also meant that they spent almost three hours less per day living in a state of hyperglycaemia,” Wadley said. “This is extremely positive news as hyperglycaemia is a risk factor for cardiovascular disease in people living with type 2 diabetes,” he said.
“We also found that the proportion of people with hypertension halved after taking the vitamin C capsules, with both their systolic and diastolic blood pressure levels dropping significantly,” Wadley added. The dose of vitamin C used in the study was about 10 times the normal dietary intake and readily available from most health food stores, researchers said.
“Vitamin C’s antioxidant properties can help counteract the high levels of free radicals found in people with diabetes, and it’s encouraging to see this benefits a number of the disease’s common comorbidities, such as high blood pressure,” he said. “While physical activity, good nutrition and current diabetes medications are standard care and very important for managing type 2 diabetes, some people can find it tough to manage their blood glucose levels even with medication,” he added.