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    A study conducted by researchers in the US found that losing just one hour of rest could kill people's desire to help others, even relatives and close friends. The team noted that a bad night appeared to dampen activity in the part of the brain that encouraged social behaviour. "We discovered that sleep loss acts as a trigger of asocial behaviour, reducing the innate desire of humans to help one another," said Prof Matthew Walker, co-author of the study at the University of California. "In a way, the less sleep you get, the less social and more selfish you become."
    The researchers suggest that a chronic sleep deficit could harm social bonds and compromise the altruistic instincts that shape society. "Considering the essentiality of humans helping in maintaining cooperative, civilised societies, together with the robust erosion of sleep time over the last 50 years, the ramifications of these discoveries are highly relevant to how we shape the societies we wish to live in," said Walker.
    The team examined the willingness of 160 participants to help others with a "self-reported altruism questionnaire", which they completed after a night's sleep. Participants responded to different social scenarios on a scale from "I would stop to help" to "I would ignore them". In one experiment involving 24 participants, the researchers compared answers from the same person after a restful night and after 24 hours without sleep. The results revealed a 78% decline in self-reported eagerness to help others when tired.

(Sascha Pare. www.theguardian.com 23.08.2022. Adaptado.)

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    Because it is locked away inside the skull, the brain is hard to study. Looking at it requires finicky machines which use magnetism or electricity or both to bypass the bone. There is just one tendril of brain tissue that can be seen from outside the body without any mucking about of this sort. That is the retina. Look into someone’s eyes and you are, in some small way, looking at their brain.

    This being so, a group of researchers decided to study the structure of the eye for signs of cognitive decline. Changes in the brain, they reasoned, might lead to changes in the nervous tissue connected to it. They focused on a part of the eye called the retinal nerve-fibre layer (RNFL). This is the lowest layer of the retina and serves to link the light-sensitive tissue above to the synapses which lead to the brain. The team’s results show that people with a thin RNFL are more likely to fail cognitive tests than those with a thick one. They are also more likely to suffer cognitive decline as they age.

(www.economist.com, 30.06.2018. Adaptado.)

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Does a C-section affect the baby’s immune system?

The natural birth process can be messy, stressful, and long remembered by both moms and dads. However, there is an unexplained link between decreasing rates of vaginal delivery and increasing rates of chronic inflammatory and metabolic disease in children growing up in today’s world.

Nowadays, 20% of Cesarean sections performed worldwide have no medical justification. Although often preferred by both patients and obstetricians, Cesarean sections are not risk-free and might have a hidden impact on the baby immune system.

During the natural birth process, the baby is exposed to microorganisms from the mother. This normal exposure process has been connected to healthy gut microbiome growth, further affecting baby immune system development. Nevertheless, it is unclear whether disruption of the exposure process occurring during cesarean section affects gut microbiome formation in neonates.

A recent study published in Nature Communications determined whether the mode of delivery does affect the baby immune system. The researchers examined stool samples taken one to five days after the birth of 33 babies born by either vaginal or cesarean deliveries. They performed an analysis of the genetic material from uncultured microorganisms found in these samples. This method allows the detection of numerous bacterial strains and the evaluation of any differences in bacterial classification among samples.

The study found differences in the microbiome of babies born naturally or by a Cesarean section. Stool samples of babies delivered by Cesarean section lacked the bacteria present in samples taken from naturally born babies. In addition, the researchers extracted an immune stimulating factor called lipopolysaccharide (LPS) from the samples. This bacteria-derived substance is known to cause chronic inflammatory disease and metabolic disease in children and adults.

They used extracted LPS to stimulate cultured immune cells and quantifies the expression of several inflammationcausing factors. Interestingly, the study discovered that LPS isolated from stool samples of naturally born babies stimulates higher levels of inflammation-related substances secretion. On the other hand, LPS isolated from stool samples of babies delivered by Cesarean section had lower inflammatory effects.

The results suggest that Cesarean section procedures divert the process of gut microbiome development to alternative pathways. This alteration might underlie the increase in the prevalence of chronic inflammatory and metabolic diseases in developed countries.

It seems that the mode of delivery might have lifelong influences on a newborn’s health.

Adaptado de: https://medicalnewsbulletin.com/c-section-babyimmune-system/ Acessado em 02 de março de 2020.

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New material could replace plastic or glass in construction of energy-efficient homes

Nicola Davis

    In an era of glass and steel construction, wood may seem old-school. But now researchers say they have given wood a makeover to produce a material that is not only sturdy, but also transparent and able to store and release heat. The researchers say the material could be used in the construction of energy-efficient homes, and that they hope to develop a biodegradable version soon to increase its eco-friendly credentials as an alternative to plastic, glass or even cement.

    “We prepared a material that is multifunctional since it can transmit light very well and also it can store heat. We combined these two functions in a single material,” said Céline Montanari of the KTH Royal Institute of Technology in Stockholm. Montanari is presenting the work at the spring national meeting of the American Chemical Society in Orlando.

    To produce the material, the team built on previous work in which they took balsa wood and removed its lignin – a component of wood that gives it strength and colour. Acrylic, which is non-biodegradable and water-repellent, was introduced into the remaining tissues where it filled both the tiny pores left by the removal of lignin and the hollow vessels that carried water in the tree. That, said Montanari, not only helped maintain the wood’s structure but also restored its strength and improved its optical properties. The upshot was a frosted-looking wood-based material.

    In the latest work, the acrylic was mixed with another substance called polyethylene glycol, which permeates wood well. Crucially, polyethylene glycol also has another feature: when it is heated it absorbs energy and melts, but when temperatures fall it hardens, releasing energy in the process. The team say this property means their wood-based material, which goes from semi-transparent to transparent when warmed, could be used to make buildings more energy-efficient, with energy captured from the sun during the day released later into the interior.

    However, Montanari said there was plenty of work still to do – including replacing the acrylic with a biodegradable alternative for some applications, scaling up production of the material, and carrying out computer models of buildings to see how transparent wood compares with glass.

(www.theguardian.com/environment/2019/apr/03/scientists-inventtransparent-wood-in-search-for-eco-friendly-building-material. Adaptado)

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The drugs don’t work: what happens after antibiotics?

Antibiotic resistance is growing so fast that routine surgery could soon become impossible. But scientists are fighting back in the battle against infection

1- The first antibiotic that didn’t work for Debbi Forsythe was trimethoprim. In March 2016, Forsythe, a genial primary care counsellor from Morpeth, Northumberland, contracted a urinary tract infection. UTIs are common: more than 150 million people worldwide contract one every year. So when Forsythe saw her GP, they prescribed the usual treatment: a three-day course of antibiotics. When, a few weeks later, she fainted and started passing blood, she saw her GP again, who again prescribed trimethoprim.

2- Three days after that, Forsythe’s husband Pete came home to find his wife lying on the sofa, shaking, unable to call for help. He rushed her to A&E. She was put on a second antibiotic, gentamicin, and treated for sepsis, a complication of the infection that can be fatal if not treated quickly. The gentamicin didn’t work either. Doctors sent Forsythe’s blood for testing, but such tests can take days: bacteria must be grown in cultures, then tested against multiple antibiotics to find a suitable treatment. Five days after she was admitted to hospital, Forsythe was diagnosed with an infection of multi-drug-resistant E coli, and given ertapenem, one of the so-called “last resort” antibiotics.

3- It worked. But damage from Forsythe’s episode has lingered and she lives in constant fear of an infection reoccurring. Six months after her collapse, she developed another UTI, resulting, again, in a hospital stay. “I’ve had to accept that I will no longer get back to where I was,” she says. “My daughter and son said they felt like they lost their mum, because I wasn’t who I used to be.” But Forsythe was fortunate. Sepsis currently kills more people in the UK than lung cancer, and the number is growing, as more of us develop infections immune to antibiotics.

4- Antimicrobial resistance (AMR) – the process of bacteria (and yeasts and viruses) evolving defense mechanisms against the drugs we use to treat them – is progressing so quickly that the UN has called it a “global health emergency”. At least 2 million Americans contract drug-resistant infections every year. So-called “superbugs” spread rapidly, in part because some bacteria are able to borrow resistance genes from neighbouring species via a process called horizontal gene transfer. In 2013, researchers in China discovered E coli containing mcr-1, a gene resistant to colistin, a last-line antibiotic that, until recently, was considered too toxic for human use. Colistin-resistant infections have now been detected in at least 30 countries.

5- “In India and Pakistan, Bangladesh, China, and countries in South America, the resistance problem is already endemic,” says Colin Garner, CEO of Antibiotic Research UK. In May 2016, the UK government’s Review on Antimicrobial Resistance forecast that by 2050 antibiotic-resistant infections could kill 10 million people per year – more than all cancers combined.

6- “We have a good chance of getting to a point where for a lot of people there are no [effective] antibiotics,” Daniel Berman, leader of the Global Health team at Nesta, told me. The threat is difficult to imagine. A world without antibiotics means returning to a time without organ transplants, without hip replacements, without many now-routine surgeries. It would mean millions more women dying in childbirth; make many cancer treatments, including chemotherapy, impossible; and make even the smallest wound potentially lifethreatening. As Berman told me: “Those of us who are following this closely are actually quite scared.”

7- Bacteria are everywhere: in our bodies, in the air, in the soil, coating every surface in their sextillions. Many bacteria produce antibiotic compounds – exactly how many, we don’t know – probably as weapons in a microscopic battle for resources between different strains of bacteria that has been going on for billions of years. Because bacteria reproduce so quickly, they are able to evolve with astonishing speed. Introduce bacteria to a sufficiently weak concentration of an antibiotic and resistance can emerge within days. Penicillin resistance was first documented in 1940, a year before its first use in humans. (A common misconception is that people can become antibioticresistant. They don’t – the bacteria do.)

Oliver Franklin-Wallis Sun 24 Mar 2019 In: https://www.theguardian.com/global/2019/mar/24/ the-drugs-dont-work-what-happens-after-antibiotics

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Is alkaline water really better for you?

    Despite the claims, there’s no evidence that water marketed as alkaline is better for your health than tap water. “It’s all about marketing,” said Tanis Fenton, a registered dietitian and epidemiologist at Cumming School of Medicine at the University of Calgary. “There is no science to back it up.”

    The pH scale indicates whether a liquid is more acidic (lower pH) or alkaline (higher pH). Pure water has a neutral pH of 7, while tap water has some natural variation depending on its mineral content. Most bottled waters are slightly acidic, and sodas and juices are even more so. Bottled waters marketed as being alkaline typically claim to have a pH between 8 and 10. Some are from springs or artesian wells and are naturally alkaline because of dissolved minerals. Others are made with an ionizing process, and water ionizing machines are also marketed for home use.

    Alkaline water companies make vague claims that it will “energize” and “detoxify” the body and lead to “superior hydration.” And some claim that ionized water can prevent everything from headaches to cancer. Nevertheless, there’s no evidence that drinking water with a higher pH can change the pH of your body, or even that this outcome would provide benefits. Blood is tightly regulated at around pH 7.4, while the stomach, which secretes hydrochloric acid to digest proteins and kill food-borne pathogens, is very acidic, with a pH of 1.5 to 3.5. If you drink water that is slightly alkaline, Dr. Fenton said, the hydrochloric acid in the stomach quickly neutralizes it before it’s absorbed into the blood.

    Several small studies funded by companies that sell alkaline water suggest that it could improve hydration in athletes, but any potential benefits were modest, and an easier way to improve hydration is just to drink more water. And a 2016 review of research by Dr. Fenton and a colleague found no evidence that alkaline water or an alkaline diet could treat or prevent cancer.

    A study published last year found that adopting a plantbased diet and drinking alkaline water worked as well as medications to alleviate the symptoms of laryngopharyngeal reflux, a severe form of acid reflux in which stomach acid travels all the way up to the throat. “I think that it can be a helpful tool for patients to help with their symptoms while they’re transitioning to a more plant-based diet,” said Dr. Craig Zalvan, the study’s lead author and a laryngologist at Phelps Hospital in Sleepy Hollow, N.Y. But he believes that most of the improvement in his patients comes from dietary changes rather than alkaline water. Once symptoms improve, he says there’s no need to keep drinking alkaline water.

(Alice Callahan. www.nytimes.com, 27.04.2018. Adaptado.)