Category Archives: Human Reproduction

The Cabinet is to propose terms of reference for a Special Joint Oireachtas Committee to report with recommendations on international surrogacy.

It will be given four months to complete its work.

The committee will be provided with an issues paper drafted by officials in the Departments of Justice, Health and Children, in consultation with relevant ministers and their officials, to assist the committee in its deliberations.

The recommendations of the committee will then be considered by the Minister for Health as the Assisted Human Reproduction Bill progresses through the legislative process.

It is expected that any necessary legislative provisions which arise out of the committee's examination will be inserted into the Assisted Human Reproduction Bill at committee stage.

The Department of Justice says the Government has committed to dealing with international surrogacy.

It notes that while the Department of Health has responsibility for the forthcoming Health (Assisted Human Reproduction) Bill, issues which arise from international surrogacy, including commercial surrogacy in other jurisdictions, "raise important questions in respect of rights and ethics, and concern areas of law that intersect across the remits of several government departments".

The statement adds that there has been "substantial work and engagement on this issue" since the formation of the Government between Ministers Helen McEntee, Hildegarde Naughton, Stephen Donnelly and Roderic OGorman and the Attorney General and their respective officials.

The memorandum is expected to be brought to Cabinet in the coming weeks.

It will propose how to consider the issues relating to international surrogacy and how to subsequently introduce legislative change.

The joint memo will be brought to Government by the Ministers for Justice, Health and Children.

Meanwhile, surrogacy advocates have described as "bonkers" that surrogacy legislation has not been put in place in Ireland as they join families protesting at Leinster House to highlight their frustration at the slow pace of progress.

A spokesperson for Irish Families Through Surrogacy said they are concerned that a new draft bill on assisted human reproduction will exclude international surrogacy and leave families and children without any legal protection.

Speaking on RT's Today with Claire Byrne, Cathy Wheatley said: "We want our children to be afforded the same provisions as every child in Ireland and have a legal relationship with both parents."

She added that "there are ways forward ... time has moved on, England legislated in 1985 for surrogacy and it is bonkers that in 2021 we have no legislation".

Ms Wheatley said that they want guarantees that international surrogacy will be included in the bill.

"All we are asking for is to create an ethical framework so that everyone is protected," she said.

Ms Wheatley said the first commission on surrogacy was introduced in 2000 and the issue has been "kicked down the road" since then, with ten committees looking at the issue.

She said that the families "know the Government will do the right thing", but that plans to set up another committee will not be enough.

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Families protest over slow pace of surrogacy laws - RTE.ie

There's an odd twist to human physiology not seen in any other primatethat makes giving birth more complicated for our species. Now, a study using biomechanical modelling on gait and posture has provided some insights into this long-standing mystery.

The narrow shape of the human birth canal is kinked at the inlet, so that contractions of the mother must rotate the baby's big brain and wide shoulders nearly 90 degrees to fit into the pelvis.

Imagine sliding a foot into a tight boot with a twisted entrance and you've got a rough idea of how challenging this can be. If the baby gets stuck, it can endanger both the life of the mother and child. In fact, this is thought to occur inas many as 6 percent of all births worldwide.

So what's the advantage? Surprisingly, for such a key element in the reproduction of our very species, we're still trying to figure that out.

(Stansfield et al., BMC Biology, 2021)

Above:The rotational birth of humans. A) shows the head turning about 90 to fit into the largest dimension of the pelvic plane; B) shows the layers of the birth canal.

Today, some of the most fundamental parts of human pregnancy are a complete mystery. We don't know, for instance, why our species undergoes such long and dangerous labors compared to other mammals.

Traditionally, it is thought the human pelvis is shaped the way it is to make walking easier.Evolutionarily speaking, the advantages of bipedal movement on a daily basis were clearly worth the extra risks that came with having narrow hips and big-brained babies.

In the new study, extensive biomechanical models of the pelvic floor suggest the shape of the birth canal doesn't help us walk so much as it helps us stand up.

"We argue that the transverse elongation of the pelvic inlet has evolved because of the limits on the front-to-back diameter in humans imposed by balancing upright posture, rather than by the efficiency of the bipedal locomotion", says Philipp Mitteroecker, who was also involved in this study."

If the inlet from the womb to the birth canal was a deeper oval, a baby could slide right through without very many fussy movements at all, as they do in other primates.

But in a human, this would require the pelvis to tilt at an even greater degree than it already does, which would add a deeper curve to the lower back.

Ultimately, the new models suggest that extra curve would compromise the stability and health of our spines, which is possibly why the inlet to the birth canal evolved a new shape instead.

In comparison, other primates, like chimpanzees, can afford to have a deeper inlet to the pelvis because they are mostly on all fours and aren't putting a lot of weight on their hips. To get through to the birth canal, chimpanzee young only have to twist their heads a little.

The human baby, by comparison, has to move their body nearly 90 degrees to face the mother's spine to fit through the tight ellipsoid.

Even after this tricky maneuver, it's not a straight slide into the world. The outlet of the human birth canal is also shaped slightly different to primates. It requires the baby to once again turn to get its shoulders out, which are widest on a different axis to the head.

The models run by researchers suggest the outlet of the birth canal is shaped this way to better support the pelvic floor.

If the lower birth canal had an outlet that was wider still, the results indicate it would help pelvic floor stability even more; however, it would ultimately make childbirth too risky. The final twist would be too hard for the head and shoulders to shimmy through.

"Our results provide a novel evolutionary explanation for the twisted shape of the human birth canal," the authors conclude.

It's an intriguing idea from a well-thought out model, but real-world research will be needed to determine if this is really why humans are born with a twist and a shout.

Evolutionary studies, for instance, have shown female Neanderthals had birth canals more similar to chimpanzees, which suggests twisting is a uniquely human and relatively recent evolutionary development.

Given that Neanderthals also stood and walked on two feet, it would be interesting to compare the biomechanics of ancient humans to figure out why the modern human pelvis stands out.

The study was published in BMC Biology.

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Human Birth Canals Are Seriously Twisted. Researchers Think They've Figured Out Why - ScienceAlert

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This article was exclusively written forThe European Stingby Mr. Natan Q. A. da Silva, a 5th year medical student from Brazil and Ms. Maria L. C. Meurer, a 4thyear medical student of UNING, Brazuk. They are affiliated with the International Federation of Medical Students Associations (IFMSA), cordial partner of The Sting. The opinions expressed in this piece belong strictly to the writer and do not necessarily reflect IFMSAs view on the topic, nor The European Stings one.

Faced with a pandemic, the mental health of younger people can be harmed, as social isolation which is beneficial for containing COVID-19 has the potential to result in psychological damage for children and adolescents. Most young people have a milder infection against the virus, but they are more psychologically impacted by changes in their social environment.

Quarantine was adopted as a preventive measure to prevent an increase in the number of those contaminated by Sars-CoV-2. This condition, together with uncertainties about the future, such as unemployment and online classes, cause emotional instability and anxiety in most young people. This whole situation is well exemplified by the following sentence from Tedros Adhanom Ghebreyesus Director General of the World Health Organization (WHO) The indirect effects of COVID-19 on children and adolescents can be greater than the number of deaths directly caused by the virus. In other words, we should be concerned about the direct effects of COVID-19, without underestimating the indirect effects that this disease can cause.

The pandemic imposed some psychosocial challenges for the youth, mainly exposed by the loss of freedom, lack of a routine in schools (in person) and restriction of socializing with friends. Worries, fears, anxiety, changes in sleep, appetite and mood are possible consequences of changes in the child-juvenile psychosocial sphere.

Another point that should be highlighted is suicidal ideation in young people who already suffer from some mental disorder, as social isolation, the theme of death/illness, economic crisis and changes in family dynamics can present themselves as triggering factors in the suicidal spectrum. All these points mentioned are found and aggravated by the pandemic.

Going through this situation as a young student during the pandemic period, I was able to experience this in practice, not only experiencing the feeling of anxiety, but uncertainty about the troubled period we are living in, the future job market, my own social life practically non-existent and its direct consequences on the quality of life and study. Currently, after a year of experiencing the pandemic, I see my life and my friends still trying to adapt to this new reality, witnessing a much more lonely form of youth.

Bibliography

HOSPITAL SANTA MNICA.Hospital Santa Mnica. 2020. Available from: <https://hospitalsantamonica.com.br/os-efeitos-da-quarentena-na-saude-mental-de-criancas-e-adolescentes/>. Access on: 24 jun. 2021.

Available from: <https://www.cremepe.org.br/2020/11/23/ensino-hibrido-ou-100-remoto/>. Access on: 24 jun. 2021.

FIOCRUZ.FIOCRUZ. 2020. Available from: <https://portal.fiocruz.br/documento/covid-19-e-saude-da-crianca-e-do-adolescente>. Access on: 24 jun. 2021.

About the authors

Natan Q. A. da Silva is a 5th year medical student from Brazil; he is a participant in the Academic Leagues of Cardiology, Orthopedics, Human Reproduction and Traumatology.

Maria L. C. Meurer is a 4thyear medical student of UNING and a member of IFMSA Brazil. She is interested in human rights and medicine and her hobbies include reading and participating in extension activities from her university.

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The mental health of young people in the pandemic - The European Sting

There were 113 cases of Covid-19 in the community today, down from yesterdays record high of 206 - New Zealands highest number since the pandemic began. Video / NZ Herald

ANALYSIS:

Now that American kids aged 5 to 11 are eligible for Covid-19 vaccination and the number of fully vaccinated people in the US is rising, many people may be wondering what the endgame is for Covid-19.

Early on in the pandemic, it wasn't unreasonable to expect that SARS-CoV-2 (the virus that causes Covid-19) might just go away, since historically some pandemic viruses have simply disappeared.

For instance, SARS-CoV, the coronavirus responsible for the first SARS pandemic in 2003, spread to 29 countries and regions, infecting more than 8000 people from November 2002 to July 2003. But thanks to quick and effective public health interventions, SARS-CoV hasn't been observed in humans in almost 20 years and is now considered extinct.

On the other hand, pandemic viruses may also gradually settle into a relatively stable rate of occurrence, maintaining a constant pool of infected hosts capable of spreading the virus to others. These viruses are said to be "endemic".

Examples of endemic viruses in the United States include those that cause the common cold and the seasonal flu that appear year after year. Much like these, the virus that causes Covid-19 likely won't die out, and most experts now expect it to become endemic.

We are a team of virologists and immunologists from the University of Colorado Boulder studying animal viruses that infect humans. An essential focus of our research is to identify and describe the key adaptations that animal viruses require to persist in the human population.

So why did the first SARS virus from 2003 (SARS-CoV) go extinct while this one (SARS-CoV-2) may become endemic?

The ultimate fate of a virus depends on how well it maintains its transmission. Generally speaking, viruses that are highly contagious, meaning that they spread really well from one person to the next, may never die out on their own because they are so good at finding new people to infect.

When a virus first enters a population with no immunity, its contagiousness is defined by scientists using a simple mathematical term, called R0. This is also referred to as the reproduction number. The reproduction number of a virus represents how many people, on average, are infected by each infected person.

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For example, the first SARS-CoV had an R0 of about 2, meaning that each infected person passes the virus to two people on average. For the Delta variant strain of SARS-CoV-2, the R0 is between 6 and 7.

The goal for public health authorities is to slow the rate by which viruses spread. Universal masking, social distancing, contact tracing and quarantines are all effective tools to reduce the spread of respiratory viruses. Since SARS-CoV was poorly transmissible, it just took a little bit of public health intervention to drive the virus to extinction. Given the highly transmissible nature of the Delta variant, the challenge for eliminating the virus will be much greater, meaning that the virus is more likely to become endemic.

It's clear that SARS-CoV-2 is very successful at finding new people to infect, and that people can get infected after vaccination. For these reasons, the transmission of this virus is not expected to end. It's important that we consider why SARS-CoV-2 moves so easily from one person to the next, and how human behaviour plays into that virus transmission.

SARS-CoV-2 is a respiratory virus that is spread through the air and is efficiently transmitted when people congregate. Critical public health interventions, like mask use and social distancing, have been key in slowing the spread of disease. However, any lapse in these public health measures can have dire consequences.

For instance, a 2020 motorcycle rally brought together nearly 500,000 people in Sturgis, South Dakota, during the early phases of the pandemic. Most of the attendees were unmasked and not practicing social distancing. That event was directly responsible for an increase in Covid-19 cases in the state of South Dakota and nationwide. This shows how easily the virus can spread when people let their guard down.

The virus that causes Covid-19 is often associated with superspreading events, in which many people are infected all at once, typically by a single infected individual.

In fact, our own work has shown that just 2 per cent of the people infected with Covid-19 carry 90 per cent of the virus that is circulating in a community. These important "supercarriers" have a disproportionately large impact on infecting others, and if they aren't tracked down before they spread the virus to the next person, they will continue to sustain the epidemic. We currently don't have a nationwide screening programme in the US geared toward identifying these individuals.

Finally, asymptomatically infected people account for roughly half of all infections of Covid-19. This, when coupled with a broad range of time in which people can be infectious two days before and 10 days after symptoms appear affords many opportunities for virus transmission, since people who don't know they are sick generally take few measures to isolate from others.

The contagious nature of SARS-CoV-2 and our highly interconnected society constitute a perfect storm that will likely contribute to sustained virus spread.

Given the considerations discussed above and what we know about Covid-19 so far, many scientists believe that the virus that causes Covid-19 will likely settle into endemic patterns of transmission. But our inability to eradicate the virus does not mean that all hope is lost.

Our post-pandemic future will heavily depend on how the virus evolves over the coming years. SARS-CoV-2 is a completely new human virus that is still adapting to its new host. Over time, we may see the virus become less pathogenic, similar to the four coronaviruses that cause the common cold, which represent little more than a seasonal nuisance.

Global vaccination programmes will have the greatest impact on curbing new cases of the disease. However, the SARS-CoV-2 vaccine campaign so far has touched only a small percentage of people on the planet. In addition, breakthrough infections in vaccinated people still occur because no vaccine is 100 per cent effective. This means that booster shots will likely be needed to maximise vaccine-induced protection against infection.

With global virus surveillance and the speed at which safe and effective vaccines have been developed, we are well poised to tackle the ever-evolving target that is SARS-CoV-2. Influenza is endemic and evolves quickly, but seasonal vaccination enables life to go on as normal. We can expect the same for SARS-CoV-2 eventually.

Four seasonal coronaviruses circulate in humans endemically already. They tend to recur annually, usually during the winter months, and affect children more than adults. The virus that causes Covid-19 has not yet settled down into these predictable patterns and instead is flaring up unpredictably around the globe in ways that are sometimes difficult to predict.

Once rates of SARS-CoV-2 stabilise, we can call it endemic. But this transition may look different based on where you are in the world. For instance, countries with high vaccine coverage and plentiful boosters may soon settle into predictable spikes of Covid-19 during the winter months when the environmental conditions are more favorable to virus transmission. In contrast, unpredictable epidemics may persist in regions with lower vaccination rates.

Sara Sawyer is a professor of molecular, cellular and developmental biology at the University of Colorado Boulder; Arturo Barbachano-Guerrero is a postdoctoral researcher in virology at the University of Colorado Boulder; Cody Warren is a postdoctoral fellow in virology and immunology at the University of Colorado Boulder.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Covid 19 Delta outbreak: Is Covid here to stay? Biologists explain what it means for a virus to become endemic - New Zealand Herald

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Bacteriophages are viruses that infect bacteria and play a potential role in the evolution of life.

Viruses have a bad reputation. They are responsible for the COVID-19 pandemic and a long list of maladies that have plagued humanity since time immemorial. Is there anything to celebrate about them?

Many biologists like me believe there is, at least for one specific type of virus namely, bacteriophages, or viruses that infect bacteria. When the DNA of these viruses is captured by a cell, it may contain instructions that enable that cell to perform new tricks.

Bacteriophages, or phages for short, keep bacterial populations in check, both on land and at sea. They kill up to 40% of the oceans bacteria every day, helping control bacterial blooms and redistribution of organic matter.

Bacteriophages are viruses that kill specific types of bacteria.

Their ability to selectively kill bacteria also has medical doctors excited. Natural and engineered phages have been successfully used to treat bacterial infections that do not respond to antibiotics. This process, known as phage therapy, could help fight antibiotic resistance.

Recent research points to another important function of phages: They may be natures ultimate genetic tinkerers, crafting novel genes that cells can retool to gain new functions.

Bacteriophage caspids can carry extra DNA that the virus can tinker with.

Phages are the most abundant life form on the planet, with a nonillion thats a 1 with 31 zeroes after it of them floating around the world at any moment. Like all viruses, phages also have high replication and mutation rates, meaning they form many variants with different characteristics each time they reproduce.

Most phages have a rigid shell called a capsid that is filled with their genetic material. In many cases, the shell has more space than the phage needs to store the DNA essential for its replication. This means that phages have room to carry extra genetic baggage: genes that are not actually necessary for the phages survival that it can modify at will.

To see how this plays out, lets take a deeper look at the phage life cycle.

Phages come in two main flavors: temperate and virulent. Virulent phages, like many other viruses, operate on an invade-replicate-kill program. They enter the cell, hijack its components, make copies of themselves and burst out.

Temperate phages, on the other hand, play the long game. They fuse their DNA with the cells and may lay dormant for years until something triggers their activation. Then they revert to virulent behavior: replicate and burst out.

Many temperate phages use DNA damage as their trigger. Its sort of a Houston, we have a problem signal. If the cells DNA is being damaged, that means the DNA of the resident phage is likely to go next, so the phage wisely decides to jump ship. The genes that direct phages to replicate and burst out are turned off unless DNA damage is detected.

Virulent phages follow the lytic cycle of viral reproduction, destroying their hosts as soon as they complete replication. Temperate phages, on the other hand, follow the lysogenic cycle and stay dormant inside their hosts DNA until theyre triggered to burst out. Credit: CNX OpenStax/Wikimedia Commons

Bacteria have retooled the mechanisms controlling that life cycle to generate a complex genetic system that my collaborators and I have been studying for over two decades.

Bacterial cells are also interested in knowing if their DNA is getting busted. If it is, they activate a set of genes that attempt to repair the DNA. This is known as the bacterial SOS response because, if it fails, the cell is toast. Bacteria orchestrate the SOS response using a switch-like protein that responds to DNA damage: It turns on if there is damage and stays off if there isnt.

Perhaps not surprisingly, bacterial and phage switches are evolutionarily related. This prompts the question: Who invented the switch, bacteria or viruses?

Our previous research and work by other researchers indicates that phages got there first. In our recent report, we discovered that the SOS response of Bacteroidetes, a group of bacteria that comprise up to a half of the bacteria living in your gut, is under control of a phage switch that was retooled to implement the bacterias own complex genetic programs. This suggests that bacterial SOS switches are in fact phage switches that got retooled eons ago.

When a temperate phage infects a bacterial cell and integrates its genome with the cells DNA, it typically lays dormant until its triggered to burst out of the cell. But once the phages DNA is part of the bacteriums, mutations can disrupt the phages genetic material and render it inactive. This means that when DNA damage occurs, the phage wont be able to reform itself and burst out. Over time, the bacterium may adapt the phages switch to control its own SOS response genes. Credit: Miquel Snchez-Osuna/Created with BioRender.com

Its not just bacterial switches that appear to be phage inventions. Beautiful detective work has shown that a bacterial gene needed for cell division also arose through domestication of a phage toxin gene. And many bacterial attack systems, such as toxins and the genetic guns used to inject them into cells, as well as the camouflage they use to evade the immune system, are known or suspected to have phage origins.

OK, you may think, phages are great, but the viruses that infect us are certainly not cool. Yet there is mounting evidence that the viruses that infect plants and animals are also a major source of genetic innovation in these organisms. Domesticated viral genes have been shown, for instance, to play a key role in the evolution of mammalian placentas and in keeping human skin moist.

Recent evidence suggests that even the nucleus of a cell, which houses DNA, could have also been a viral invention. Researchers have also speculated that the ancestors of todays viruses may have pioneered the use of DNA as the primary molecule for life. Not a small feat.

So while you may be used to thinking of viruses as the quintessential villains, they are arguably natures powerhouses for genetic innovation. Humans are likely here today because of them.

Written by Ivan Erill, Associate Professor of Biological Sciences, University of Maryland, Baltimore County.

Originally published on The Conversation.

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Viruses Are Both the Villains and Heroes of Life As We Know It Natures Powerhouses for Genetic Innovation - SciTechDaily