New York (IANS) - Psychosocial stress -- typically resulting from difficulty coping with challenging environments -- may work synergistically to put women at higher risk of developing coronary heart disease, a new study suggests.
The findings indicate that the effects of job strain and social strain -- the negative aspect of social relationships -- on women is a powerful one-two punch. Together they are associated with a 21 per cent higher risk of developing coronary heart disease.
"The Covid-19 pandemic has highlighted ongoing stresses for women in balancing paid work and social stressors," said researchers Yvonne Michael, Associate Professor at Drexel University in the US.
"My hope is that these findings are a call for better methods of monitoring stress in the workplace and remind us of the dual-burden working women face as a result of their unpaid work as caregivers at home," Michael added.
The study also found that high-stress life events, such as a spouse's death, divorce/separation or physical or verbal abuse, as well as social strain, were each independently linked with a 12 per cent and 9 per cent higher risk of coronary heart disease, respectively.
For the study, published in the Journal of the American Heart Association, the team used data from a nationally representative sample of 80,825 postmenopausal women.
In the current follow-up study, the researchers evaluated the effect of psychosocial stress from job strain, stressful life events and social strain (through a survey), and associations among these forms of stress, on coronary heart disease.
Nearly 5 per cent of the women developed coronary heart disease during the 14-year, seven-month study.
Coronary heart disease, the leading cause of death in the US, occurs with the heart's arteries become narrow and cannot bring sufficient oxygenated blood to the heart.
New York, April 3 (IANS) Researchers have identified the biological mechanism by which chronic stress impairs hair follicle stem cells, confirming long-standing observations that stress might lead to hair loss.
In a mouse study, published in the journal Nature, the researchers found that a major stress hormone puts hair follicle stem cells into an extended resting phase, without regenerating the follicle or the hair.A
The researchers identified the specific cell type and molecule responsible for relaying the stress signal to the stem cells and showed that this pathway can be potentially targeted to restore hair growth.
"The skin offers a tractable and accessible system to study this important problem in depth, and in this work, we found that stress does actually delay stem-cell activation and fundamentally changes how frequently hair follicle stem cells regenerate tissues," said researcher Ya-Chieh Hsu from Harvard University.
The hair follicle naturally cycles between growth and rest, a process fuelled by hair follicle stem cells. During the growth phase, hair follicle stem cells become activated to regenerate the follicle and hair, and hairs grow longer each day.
During the resting phase, the stem cells are quiescent and hairs shed more easily. Hair loss can occur if the hairs shed and the stem cells remain quiescent without regenerating new tissue.
The researchers studied a mouse model of chronic stress and found that hair follicle stem cells stayed in a resting phase for a very long time without regenerating tissues.A
A major stress hormone produced by the adrenal glands, corticosterone, was upregulated by chronic stress; giving mice corticosterone reproduced the stress effect on the stem cells.A
The equivalent hormone in humans is cortisol, which is often referred to as the "stress hormone."
Under normal conditions, hair follicle regeneration slows over time -- the resting phase becomes longer as the animals age.
But when the researchers removed the stress hormones, the stem cells' resting phase became extremely short and the mice constantly entered the growth phase to regenerate hair follicles throughout their life, even when they were old.
New York - A US-based survey has revealed that stress, increased free time and feelings of boredom may have contributed to an increase in the number of cigarettes smoked per day during the early months of the Covid-19 pandemic.
The findings, published in the International Journal of Environmental Research and Public Health, indicated that smokers who increased the number of cigarettes they smoked per day could be at greater risk of dependence and have a more difficult time quitting.
"Knowing the reasons for increased tobacco use and the motivations of those who successfully quit smoking can help us identify how to better address cessation efforts during the pandemic," said researcher Jessica Yingst, Assistant Professor at the Pennsylvania State University in the US.
For the study, the research team asked 291 smokers in Pennsylvania about their tobacco use patterns before and during the early months of the pandemic including how frequently they used tobacco products, reasons why their use patterns changed and whether they attempted to quit.
Nearly a third of smokers reporting increased use due to stress, increased free time and boredom. One participant stated, "Working at home allows me to smoke at will rather than being in a smoke-free environment for 8 hours per day."
In contrast, 10 per cent of participants decreased their tobacco use and attributed that to schedule changes, being around non-smokers such as children and health reasons.
Nearly a quarter of participants reported attempting to quit smoking during the pandemic. A third of those who attempted to quit conveyed that they did so to reduce their risk of poor outcomes should they become infected with Covid-19.
One participant stated, "I quit as soon as I came down with a fever and cough. Clearly, I am aware of how detrimental smoking is to my health; however, I did not consider how it could make me more vulnerable to Covid-19 and its effects. I was terrified and quit immediately."
Ultimately, seven people were successful in quitting all tobacco use. (Agency)
New York, Pregnant women who consumed caffeine as little as half a cup of coffee a day on an average had slightly smaller babies than pregnant women who did not consume caffeinated beverages, a new study revealed.
The study found corresponding reductions in size and lean body mass for infants whose mothers consumed below the 200 milligrams of caffeine per day -- about two cups of coffee -- believed to increase risks to the fetus.
Smaller birth size can place infants at higher risk of obesity, heart disease and diabetes later in life.
"Until we learn more, our results suggest it might be prudent to limit or forego caffeine-containing beverages during pregnancy," said researcher Katherine L. Grantz from the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development.
For the study, published in the JAMA Network Open,A the team analyzed data on more than 2,000 racially and ethnically diverse women at 12 clinical sites who were enrolled from 8 to 13 weeks of pregnancy.
From weeks 10 to 13 of pregnancy, the women provided a blood sample that was later analyzed for caffeine and paraxanthine, a compound produced when caffeine is broken down in the body.
Compared to infants born to women with no or minimal blood levels of caffeine, infants born to women who had the highest blood levels of caffeine at enrollment were an average of 84 grams lighter at birth (about three ounces), were 0.44 centimeters shorter (about .17 inches), and had head circumferences 0.28 centimeters smaller (about 0.11 inches).
Based on the women's own estimates of the beverages they drank, women who consumed about 50 milligrams of caffeine a day (equivalent to a half cup of coffee) had infants 66 grams (about 2.3 ounces) lighter than infants born to non-caffeine consumers. Similarly, infants born to the caffeine consumers also had thigh circumferences 0.32 centimeters smaller (about 0.13 inches).
The researchers noted that caffeine is believed to cause blood vessels in the uterus and placenta to constrict, which could reduce the blood supply to the fetus and inhibit growth. Similarly, researchers believe caffeine could potentially disrupt fetal stress hormones, putting infants at risk for rapid weight gain after birth and for later life obesity, heart disease and diabetes. (agency)
Tokyo, Increased allergic reactions may be tied to the corticotropin-releasing stress hormone (CRH), suggests a new study.
The hormone is the main element that drives the body's response to stress. It is also present in diseases that cause inflammation.
The study, published in the International Journal of Molecular Sciences, suggests that the findings may help clarify the mechanism by which CRH induces proliferation of mast cells (MC) -- agents involved in the development of allergies in the human nasal cavity.
"In my daily practice, I meet many patients with allergies who say their symptoms worsened due to psychological stress," said lead researcher Mika Yamanaka-Takaichi from the Osaka City University in Japan.
The team hypothesized that due to its role in inducing MC degranulation in human skin, "CRH may also be involved in stress-aggravated nasal allergies," the researchers said.
When the team added CRH to a nasal polyp organ culture, they saw a significant increase in the number of mast cells, a stimulation both of MC degranulation and proliferation, and an increase of stem cell factor (SCF) expression, a growth factor of mast cells, in human nasal mucosa- the skin of the nasal cavity.
In exploring possible therapeutic angles, "we saw the effect of CRH on mast cells blocked by CRHR1 gene knockdown, CRHR1 inhibitors, or an addition of SCF neutralizing antibodies," said Yamanaka-Takaichi.
In vivo, the team found an increase in the number of mast cells and degranulation in the nasal mucosa of mouse models of restraint stress, which was inhibited by the administration of CRHR1 inhibitor, antalarmin.
"In addition to understanding the effects stress has on our allergies, we have also found promising therapeutic potential in candidates like antalarmin," Yamanaka-Takaichi noted. (IANS)
Toronto - Infection with severe acute respiratory syndrome SARS-CoV-2 in pregnancy is associated with preeclampsia, stillbirth, preterm birth and other adverse outcomes, finds a new study.
The study, published in the Canadian Medical Association Journal, found double the risk of preterm birth and a 50 per cent increased risk of cesarean delivery in pregnant people with symptomatic Covid-19 than in those with asymptomatic Covid-19.
"Our findings suggest that pregnant people with Covid-19 have an increased risk of high blood pressure, stillbirth and preterm birth," said researcher Nathalie Auger from the University of Montreal in Canada.
"Their newborns are more likely to need intensive care. Pregnant people with severe Covid-19 symptoms have a particularly high risk of these complications," Auger added.
For the study, the team reviewed 42 studies involving 438,548 pregnant people from around the world to determine the association between SARS-CoV-2 infection and adverse pregnancy outcomes.
The study indicated that those with severe Covid-19 had a 4-fold higher risk of high blood pressure and preterm birth.
The researchers said that the reason for the increased risk of adverse outcomes is unclear, but could be because SARS-CoV-2 may lead to vasoconstriction and stimulate an inflammatory response affecting blood vessels.
"Our meta-analysis of recent good-quality cohort studies with comparative data does not align with these previous reviews, and provides clear evidence that symptomatic or severe Covid-19 is associated with a considerable risk of preeclampsia, preterm birth and low birth weight," the team said.
"Clinicians should be aware of these adverse outcomes when managing pregnancies affected by Covid-19 and adopt effective strategies to prevent or reduce risks to patients and fetuses," they noted. (IANS)