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Category Archives: Human Reproduction

Study reveals birth defects caused by flame retardant – University of Georgia

Research focuses on mans exposure prior to conception

A new study from the University of Georgia has shown that exposure to a now-banned flame retardant can alter the genetic code in sperm, leading to major health defects in children of exposed parents.

Published recently in Scientific Reports, the study is the first to investigate how polybrominated biphenyl-153 (PBB153), the primary chemical component of the flame retardant FireMaster, impacts paternal reproduction.

In 1973, an estimated 6.5 million Michigan residents were exposed to PBB153 when FireMaster was accidentally sent to state grain mills where it made its way into the food supply. In the decades since, a range of health problems including skin discoloration, headache, dizziness, joint pain and even some cancers have been linked to the exposure.

More striking, the children of those who were exposed seemed to experience a host of health issues as well, including reports of hernia or buildup in the scrotum for newborn sons and a higher chance of stillbirth or miscarriage among adult daughters.

Yet, little work has been done to understand how the chemical exposure could have impacted genes passed from an exposed father, said study author Katherine Greeson.

It is still a relatively new idea that a mans exposures prior to conception can impact the health of his children, said Greeson, an environmental health science doctoral student in Charles Easleys lab at UGAs College of Public Health and Regenerative Bioscience Center.

Most studies where a toxic effect is observed in children look only to the mothers and the same has been true of studies conducted on PBB153, she said.

Greeson and a team of researchers from UGA and Emory University used a unique combination of observational and laboratory approaches to demonstrate how PBB153 acted on sperm cells.

Typically, scientific studies are either epidemiological in nature and inherently observational or focus on bench science, but in this study, we did both, said Greeson.

This approach allowed the researchers to mimic the known blood exposure levels of PBB153 in a lab environment.

We were uniquely able to recreate this effect using our previously characterized human stem cell model for spermatogenesis, she said, which allowed us to study the mechanism that causes this effect in humans.

The team looked at the expression of different genes in their human spermatogenesis model after dosing with PBB153 and found marked alterations in gene expression between dosed and undosed cells, specifically at genes important to development, such as embryonic organ, limb, muscle, and nervous system development.

PBB153 causes changes to the DNA in sperm in a way that changes how the genes are turned on and off, said Greeson. PBB153 seems to turn on these genes in sperm which should be turned off, said Greeson, which may explain some of the endocrine-related health issues observed in the children of exposed parents.

Though the study used this model to directly replicate exposure to PBB153, Greeson says this approach could be used to better understand the impact of other environmental exposures on reproduction, including large-scale accidental exposures to toxic chemicals or everyday exposures.

Hopefully this work will lead to more studies combining epidemiology and bench science in the future, which will tell us more about why were seeing an effect from an environmental exposure in human populations and encourage experimental studies to more closely mimic human exposures, she said.

The study, Detrimental Effects of Flame Retardant, PBB153, Exposure on Sperm and Future Generations, published May 22. It is available online.

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Study reveals birth defects caused by flame retardant - University of Georgia

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The robustness of reciprocity: Experimental evidence that each form of reciprocity is robust to the presence of other forms of reciprocity – Science…

Prosocial behavior is paradoxical because it often entails a cost to ones own welfare to benefit others. Theoretical models suggest that prosociality is driven by several forms of reciprocity. Although we know a great deal about how each of these forms operates in isolation, they are rarely isolated in the real world. Rather, the topological features of human social networks are such that people are often confronted with multiple types of reciprocity simultaneously. Does our current understanding of human prosociality break down if we account for the fact that the various forms of reciprocity tend to co-occur in nature? Results of a large experiment show that each basis of human reciprocity is remarkably robust to the presence of other bases. This lends strong support to existing models of prosociality and puts theory and research on firmer ground in explaining the high levels of prosociality observed in human social networks.

This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited.

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The robustness of reciprocity: Experimental evidence that each form of reciprocity is robust to the presence of other forms of reciprocity - Science...

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Two anti-inflammatory drugs found that may inhibit Covid-19 virus reproduction – Hindustan Times

Two anti-inflammatory drugs, one prescribed for humans and another for animals, may inhibit a key enzyme in the replication or reproduction of the novel coronavirus that causes Covid-19, according to a study.

The study, published in the International Journal of Molecular Sciences, used computer techniques to analyse 6,466 drugs authorised by various drug agencies for both human and veterinary use.

The researchers from Universitat Rovira in Spain assessed whether these drugs could be used to inhibit the main protease of the virus (M-pro) enzyme, which plays an essential role in the replication of the virus.

They found that a human and a veterinary anti-inflammatory drug -- Carprofen and Celecoxib -- inhibit a key enzyme in the replication and transcription of the virus responsible for COVID-19.

Finding drugs that can inhibit the infection caused by SARS-CoV-2 is an essential step to finding the vaccine that can definitively bring the spread of the virus to an end, according to the researchers.

M-pro enzyme is responsible for cutting two polypeptides -- generated by the virus itself -- and generating a number of proteins that are essential for the reproduction of the virus, the researchers said.

Some of the trials coordinated by the World Health Organization against the COVID-19 pandemic also aim to inhibit M-pro using two antiretrovirals such as Lopinavir and Ritonavir, drugs initially designed to treat HIV, they said.

In the new study, the researchers predicted that seven of the 6,466 drugs analysed may inhibit M-pro.

The results have been shared with the international initiative of scientists, COVID Moonshot, which has selected two of these seven compounds -- Carprofen and Celecoxib -- in order to test their ability to inhibit M-pro in vitro, they said.

The findings show that at a concentration of 50 micromolar (M) of Celecoxib or Carprofen, the inhibition of the in vitro activity of M-pro enzyme is 11.90 and 4.0 per cent, respectively.

Both molecules could be used as a starting point for further lead optimisation to obtain even more potent derivatives, the researchers said.

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Two anti-inflammatory drugs found that may inhibit Covid-19 virus reproduction - Hindustan Times

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What Australian birds can teach us about choosing a partner and making it last – The Conversation AU

Love, sex and mate choice are topics that never go out of fashion among humans or, surprisingly, among some Australian birds. For these species, choosing the right partner is a driver of evolution and affects the survival and success of a bird and its offspring.

There is no better place than Australia to observe and study strategies for bird mate choice. Modern parrots and songbirds are Gondwanan creations they first evolved in Australia and only much later populated the rest of the world.

Here, well examine the sophisticated way some native birds choose a good mate, and make the relationship last.

For years, research has concentrated on studying birds in which sexual selection may be as simple as males courting females. Males might display extra bright feathers or patterns, perform a special song or dance or, like the bowerbird, build a sophisticated display mound.

In these species, females choose the best mate on the market. But the males do not stick around after mating to raise their brood.

Read more: How the Australian galah got its name in a muddle

These reproductive strategies apply only to about tiny proportion of birds worldwide.

Then there are lovers for a season, which account for another small percentage of songbirds. Males and females may raise a brood together for one season, then go their separate ways.

These are not real partnerships at all theyre simply markets for reproduction.

But what about the other birds those that raise offspring in pairs, just as humans often do? Those that form partnerships for more than a season, and in some cases, a lifetime?

More than 90% of birds worldwide fall into this joint parenting category and in Australia, many of them stay together for a long time. Indeed, Australia is a hotspot for these cooperative and long-term affairs.

This staggering figure has no equal in the animal kingdom. Even among mammals, couples are rare; only 5% of all mammals, including humans, pair up and raise kids together.

So how do long-bonding Australian birds choose partners, and whats their secret to relationship success?

The concept of assortative mating is often used to explain how humans form lasting relationships. As the theory goes, we choose mates with similar traits, lifestyle and background to our own.

In native birds that form long-lasting bonds, including butcherbirds, drongos and cockatoos, differences between the sexes are small or non-existent that is, they are monomorphic. Males and females may look alike in size and plumage, or may both sing, build nests and provide equally for offspring.

So, how do they choose each other, if not by colour, song, dance or plumage difference? Theres some research to suggest their choices are based on personality.

Many bird owners and aviculturists would attest that birds have individual personalities. They may, for example, be gentle, tolerant, submissive, aggressive, confident, curious, fearful or sociable.

Read more: Magpies can form friendships with people here's how

Research has not conclusively established which bird personalities are mutually attractive. But so far it seems similarities or familiarity, rather than opposites, attract.

Cockatiel breeders now even use personality assessments similar to those used for show dogs.

There is practical and scientific proof to support this approach. In breeding contexts, seemingly incompatible birds may be forced together. In such cases, they are unlikely to reproduce and may not even interact with each other. For example, research on Gouldian finches has shown that in mismatched pairs, stress hormone levels were elevated over several weeks, which delayed egg laying.

Conversely, well-matched zebra finch pairs have been shown to have greater reproductive success. Well designed experiments have also shown these birds to change human-assigned partners once free to do so, suggesting firm partner preferences.

Now to some extraordinary, little-known facets of behaviour in some native birds.

Bird bonds are not always or initially about reproduction. Most cockatoos take five to seven years to mature sexually. Magpies, apostlebirds and white winged choughs cant seriously think about reproducing until they are five or six years old.

In the interim, they form friendships. Some become childhood sweethearts long before they get married and reproduce.

Socially monogamous birds, such as most Australian cockatoos and parrots, pay meticulous attention to each other. They reaffirm bonds by preening, roosting and flying together in search of food and water.

Even not-so-cuddly native songbirds such as magpies or corvids have long term partnerships and fly, feed and roost closely together.

Bird species that pair up for life, and devote the most time to raising offspring, are generally also the most intelligent (when measured by brain mass relative to body weight).

Such species tend to live for a long time as well sometimes four times longer than birds of similar weight range in the northern hemisphere.

So why is this? The brain chews up lots of energy and needs the best nutrients. It also needs time to reach full growth. Parental care for a long period, as many Australian birds provide, is the best way to maximise brain development. It requires a strong bond between the parents, and a commitment to raising offspring over the long haul.

Read more: Bird-brained and brilliant: Australia's avians are smarter than you think

Interestingly, bird and human brains have some similar architecture, and the same range of important neurotransmitters and hormones. Some of these may allow long-term attachments.

Powerful hormones that regulate stress and induce positive emotions are well developed in both humans and birds. These include oxytocin (which plays a part in social recognition and sexual behaviour) and serotonin (which helps regulate and modulate mood, sleep, anxiety, sexuality, and appetite).

The dopamine system also strongly influences the way pair bonds are formed and maintained in primates including humans and in birds.

Birds even produce the hormone prolactin, once associated only with mammals. This plays a role in keeping parents sitting on their clutch of eggs, including male birds that share in the brooding.

Given the above, one is led to the surprising conclusion that cooperation, and long-term bonds in couples, is as good for birds as it is for humans. The strategy has arguably led both species to becoming the most successful and widely distributed on Earth.

With so many of Australias native birds declining in numbers, learning as much as possible about their behaviour, including how they form lasting relationships, is an urgent task.

Much of the information referred to in this article is drawn from Gisela Kaplans books Bird Bonds. See also Bird Minds and Tawny Frogmouth

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What Australian birds can teach us about choosing a partner and making it last - The Conversation AU

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Early isotopic evidence for maize as a staple grain in the Americas – Science Advances

Maize is a cultigen of global economic importance, but when it first became a staple grain in the Americas, was unknown and contested. Here, we report direct isotopic dietary evidence from 52 radiocarbon-dated human skeletons from two remarkably well-preserved rock-shelter contexts in the Maya Mountains of Belize spanning the past 10,000 years. Individuals dating before ~4700 calendar years before present (cal B.P.) show no clear evidence for the consumption of maize. Evidence for substantial maize consumption (~30% of total diet) appears in some individuals between 4700 and 4000 cal B.P. Isotopic evidence after 4000 cal B.P. indicates that maize became a persistently used staple grain comparable in dietary significance to later maize agriculturalists in the region (>70% of total diet). These data provide the earliest definitive evidence for maize as a staple grain in the Americas.

This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited.

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Early isotopic evidence for maize as a staple grain in the Americas - Science Advances

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Indira IVF to resume in-vitro fertilisation services – Express Healthcare

All safety protocols directed by authorities will be followed to ensure safety of patients, doctors, working staff

In March, the Human Fertilisation and Embryology Authority (HFEA) ordered to pause the IVF treatment procedures in the UK. After the massive Coronavirus hit,IVFclinics were asked to postpone its services amidst the lockdown. There has been too much fear about the patients contracting the virus and they are taking all the measures to curb it. Recently, European Society of Human Reproduction and Embryology, The American Society for Reproductive Medicine and Indian health department have asked clinics to start essential services in a phased manner with all necessary safety measures.

Working as per the guidelines provided by the authorities, Indira IVF has taken a decision to restart its in-vitro fertilisation (IVF) services. All 89 clinics are open for patients who are seeking treatment with all the precautionary measures as per the guidelines provided by the Government of India.

With the current number of cases increasing aggressively, hospitals and clinics are advised to remain vigilant in the safety protocols and take all the required safety measures. Relentless adherence to safety protocols is a must.

Keeping into consideration the current COVID-19 condition, Indira IVF is following all safety protocols directed by the authorities to ensure the safety of patients, doctors and the working staff.

To ensure a safe and clean environment, the company has come up with precautions including:

Mandatory checking of temperature for all who enter the premises

Self-declaration form by the patients to identify the high-risk patients

Proper precautionary measure should be taken by the patients, doctors, and staff like gloves, masks, and others

Regular disinfection of the hospital facility

Strict sanitisation protocols

Social distancing and entry only by prior appointment

Speaking about the same, Nitiz Murdia, Marketing Director, Indira IVFsaid In this difficult time, we are keeping our focus to minimise visits a patient makes to the clinic for IVF treatment by offering tele-consultation with the treating fertility specialist. We are also taking special precaution at all our 88 clinics across pan India to strictly follow health and hygiene guidelines issued by the government for the safety of our staff and our patients. To live with COVID-19 virus is now the new way to live life hence its our collective responsibility to take all the necessary precautions to safeguard our-self as well as our family members from this virus.

Fertility clinics have shut down its services since March after the lockdown was announced. But today, fertility hospitals are trying to resume their operations.The reopening is happening in phases with new safety measures being put in place.

Speaking about the present scenario,Dr Kshitiz Murdia, Chief Operating Officer, Indira IVFsaid The impact of Coronavirus has greatly affected infertile couples who have planned to undergo treatment in summers; due to lockdown conditions in the city, couples had to postpone their treatment. The good news is that now they will be able to re-start their treatment at Indira IVF clinics. To tackle the previous load of the IVF patients, we are giving priority to patients whose embryos were frozen with us but due to lockdown they couldnt undergo embryo transfer procedure followed by other patients.

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Indira IVF to resume in-vitro fertilisation services - Express Healthcare

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