Culture

Hornwort genomes could lead to crop improvement

image: Researchers sequenced the genomes of three hornworts, including this Anthoceros agrestis. These ancient plants hold evolutionary secrets that could help crops grow more efficiently with less fertilizer.

Image: 
Image Eftychis Frangedakis

ITHACA, NY, March 13, 2020 -- Some 500 million years ago - when our continents were likely connected in a single land mass and most life existed underwater - hornworts were one of the first groups of plants to colonize land. But biologists have never understood much about the genetics of these ancient plants, which have very unique biology.

Fay-Wei Li from the Boyce Thompson Institute, Péter Szövényi from the University of Zurich and researchers from across the globe sequenced the genomes of three hornworts, illuminating the dawn of land plants. The group also discovered genes that likely underpin the plants' special methods of acquiring carbon and nitrogen.

The findings could lead to the development of crops that produce higher yields with the use of less synthetic fertilizer.

"We know life is basically built by carbon, nitrogen and phosphorus - those are key to increasing agricultural yields," said Li, BTI faculty member and a corresponding author of the paper. "If we can unlock hornworts' secrets, then we might be able to transfer those traits to agriculturally important plants."

The results were published in the journal Nature Plants on March 13.

The research team began the project in 2011, said Szövényi, a researcher at the University of Zurich and the other corresponding author of the paper. "It took us three years to figure out how hornworts can be grown and pushed through their sexual life cycle under laboratory conditions, and another three years to properly assemble and annotate their genomes."

One of the researchers' goals was to find genes that play a role in hornworts' method of concentrating carbon dioxide inside chloroplasts, which boosts the plants' ability to make sugar. Hornworts are unique among land plants in this capability, but some species of algae share the trait. The team thus compared the hornwort genomes with those of algae and found one gene, LCIB, that is shared by the two groups of plants but not with other land plants.

"If this carbon-concentrating mechanism could be installed in crop plants, then they could grow larger with the same amount of fertilizer," said Li, who is also an adjunct assistant professor of plant biology at Cornell University.

The group also identified 40 genes that may promote the hornworts' source of nitrogen, which comes from a symbiotic relationship with cyanobacteria. "That's a really unique function," Li said. "Very few plants can do this."

If crop plants could be developed to have a similar symbiotic relationship with cyanobacteria, then farmers could use less nitrogen fertilizer, said Li. Such a reduction in fertilizer could benefit the environment because excess agricultural nitrogen frequently enters waterways, where it can cause deadly algal blooms.

Li plans to further study these genes as part of a recent EDGE grant from the National Science Foundation, which seeks to develop technologies for determining the functions of hornwort genes. "Once we have the genetic tools then we will be able to investigate the roles of these genes in hornworts' unconventional ways of sourcing carbon and nitrogen," Li said.

The research also shed light on the evolution of early land plants. Hornworts, liverworts and mosses were among the first plants to colonize land, but how the three groups were related had not been clear.

"In terms of the relationship of land plants, there has been a huge debate of where hornworts sit," Li said. "Here, we have strong evidence that hornworts, liverworts and mosses are all more closely related to each other than they are to vascular plants. We also show that liverworts and mosses are more closely related to each other than to hornworts."

"The data we generated fill a really important gap in how we try to understand the evolution of land plants," added Li.

Credit: 
Boyce Thompson Institute

Coronavirus spreads quickly and sometimes before people have symptoms, study finds

Infectious disease researchers at The University of Texas at Austin studying the novel coronavirus were able to identify how quickly the virus can spread, a factor that may help public health officials in their efforts at containment. They found that time between cases in a chain of transmission is less than a week and that more than 10% of patients are infected by somebody who has the virus but does not yet have symptoms.

In the paper in press with the journal Emerging Infectious Diseases, a team of scientists from the United States, France, China and Hong Kong were able to calculate what's called the serial interval of the virus. To measure serial interval, scientists look at the time it takes for symptoms to appear in two people with the virus: the person who infects another, and the infected second person.

Researchers found that the average serial interval for the novel coronavirus in China was approximately four days. This also is among the first studies to estimate the rate of asymptomatic transmission.

The speed of an epidemic depends on two things -- how many people each case infects and how long it takes cases to spread. The first quantity is called the reproduction number; the second is the serial interval. The short serial interval of COVID-19 means emerging outbreaks will grow quickly and could be difficult to stop, the researchers said.

"Ebola, with a serial interval of several weeks, is much easier to contain than influenza, with a serial interval of only a few days. Public health responders to Ebola outbreaks have much more time to identify and isolate cases before they infect others," said Lauren Ancel Meyers, a professor of integrative biology at UT Austin. "The data suggest that this coronavirus may spread like the flu. That means we need to move quickly and aggressively to curb the emerging threat."

Meyers and her team examined more than 450 infection case reports from 93 cities in China and found the strongest evidence yet that people without symptoms must be transmitting the virus, known as pre-symptomatic transmission. According to the paper, more than 1 in 10 infections were from people who had the virus but did not yet feel sick.

Previously, researchers had some uncertainty about asymptomatic transmission with the coronavirus. This new evidence could provide guidance to public health officials on how to contain the spread of the disease.

"This provides evidence that extensive control measures including isolation, quarantine, school closures, travel restrictions and cancellation of mass gatherings may be warranted," Meyers said. "Asymptomatic transmission definitely makes containment more difficult."

Meyers pointed out that with hundreds of new cases emerging around the world every day, the data may offer a different picture over time. Infection case reports are based on people's memories of where they went and whom they had contact with. If health officials move quickly to isolate patients, that may also skew the data.

"Our findings are corroborated by instances of silent transmission and rising case counts in hundreds of cities worldwide," Meyers said. "This tells us that COVID-19 outbreaks can be elusive and require extreme measures."

Credit: 
University of Texas at Austin

Call for older people in poor countries to be considered in global responses to COVID-19

Current guidance on coronavirus "largely ignores" the implications for public health and clinical responses in light of those most at risk, according to an international group of global health experts.

Writing in the British Medical Journal, researchers from the University of East Anglia (UEA), London School of Hygiene & Tropical Medicine (LSHTM) and Samson Institute for Ageing Research (SIFAR), Cape Town, lead calls for an age perspective to be included explicitly in national and global planning on covid-19, as well as the urgent formation of an expert group on older people to support with guidance and response to the virus.

In their editorial, Prof Peter Lloyd-Sherlock of UEA, Prof Shah Ebrahim and Prof Martin McKee of LSHTM, and Dr Leon Geffen at SIFAR note that the largest numbers of deaths will occur among older people in low and middle-income countries (LMICs). These countries contain 69 per cent of the global population aged 60 and over, and health systems which are less extensive and less focussed on the needs of older people than in high-income countries.

Prof Lloyd-Sherlock, professor of social policy and international development at UEA, said: "The global response to coronavirus must be directed towards those groups who will face the most devastating consequences. So far, this has not happened. We are facing an unprecedented and enormous wave of mortality among older people in these countries."

In LMICs the risk of infection for older people will be high because living arrangements are often cramped and overcrowded. Increasing numbers of older people in LMICs live in nursing homes or similar facilities, where conditions are often poor and regulation weak.

The researchers say social distancing policies must consider the already precarious existence of many older people, particularly those living alone or dependent on others for care and support. These people may face barriers to obtaining food and other essential supplies if quarantine conditions become more widespread.

As in high-income countries, the risk of dying from covid-19 in LMICs increases sharply with age and the vast majority of deaths observed are in people over the age of 60, especially those with chronic conditions such as cardiovascular disease.

The capacity of health systems in LMICs to screen, let alone treat, the virus will be very limited: in South Africa each test costs around US$75 -this exceeds total annual government per capita health spending in many LMICs. Even before covid-19 emerged, older people already faced significant barriers of access to health services and support, including affordability, and age based discrimination.

The researchers add: "It will not be easy to deal with these problems, especially in settings where there is often weak public health infrastructure, a lack of gerontological expertise at all levels of the health system, and limited trust in government.

"However, a first step would be to recognise that these problems exist. An age perspective should be included explicitly in the development of national and global planning for covid-19, and a global expert group on older people should be formed to support with guidance and response to the virus in both residential facilities and home settings.

"As new knowledge emerges, this group can identify and evaluate cost effective therapies and interventions that respond to the particular needs of older people in LMICs living in challenging settings, where formal health service infrastructure is limited."

They conclude: "Previously, some of the authors have argued that global health priority setting is institutionally ageist. Covid-19 offers an opportunity to prove us wrong."

Credit: 
University of East Anglia

Oncotarget: DNA methylation of MMPs and TIMPs in atherothrombosis process in carotid plaques

image: Differentially methylated levels of cg04316754 (MMP24). (A) Boxplot: differentially methylated status of cg04316754. X-axis indicates sample type, in each cohort. Y-axis indicates DNA methylation levels (β-values = 0-1).0 = 0% methylation status, 1 = 100% methylation status. (B) Statistically significant differentially methylated CpG sites in plaque tissue, annotation and statistical results in the three cohorts.

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Correspondence to - Cristina Gallego-Fabrega - cristina.gallego.fabrega@gmail.com, Jerzy Krupinski - jkrupinski@mutuaterrassa.es, and Israel Fernandez-Cadenas - israelcadenas@yahoo.es

Oncotarget Volume 11, Issue 10 reported that the statistically associated Cp G sites were analyzed in blood samples from two separate atherothrombotic stroke cohorts, ischemic stroke-cohort 1: 37 atherothrombotic patients and 6 controls, ischemic stroke-cohort 2: 80 atherothrombotic patients and 184 controls.

The results suggest different DNAm status of MMP24 between stable and unstable atherothrombotic carotid plaques, and between atherothrombotic stroke and controls in blood samples.

Dr. Israel Fernandez-Cadenas from Stroke Pharmacogenomics and Genetics, Sant Pau Research Institute, Barcelona, Spain, Dr. Jerzy Krupinski from the Neurology, Hospital Universitari Mútua de Terrassa/Fundacio Docència i Recerca MútuaTerrassa, Terrassa, Spain as well as the Centre for Biomedicine, Manchester Metropolitan University, Manchester, UK & Dr. Cristina Gallego-Fabrega also from the Neurology, Hospital Universitari Mútua de Terrassa/Fundacio Docència i Recerca MútuaTerrassa, Terrassa, Spain as well as the Stroke Pharmacogenomics and Genetics, Sant Pau Research Institute, Barcelona, Spain said, "Arteriosclerosis is the underlying pathology in most cases of cardiovascular disease (CVD), including ischemic stroke (IS), contributing to major mortality in Western countries."

"Arteriosclerosis is the underlying pathology in most cases of cardiovascular disease (CVD), including ischemic stroke (IS), contributing to major mortality in Western countries"

- Dr. Israel Fernandez-Cadenas, Stroke Pharmacogenomics and Genetics, Sant Pau Research Institute & Dr. Jerzy Krupinski from the Neurology, Hospital Universitari Mútua de Terrassa/Fundacio Docència i Recerca MútuaTerrass and the Centre for Biomedicine, Manchester Metropolitan University & Dr. Cristina Gallego-Fabrega also from the Neurology, Hospital Universitari Mútua de Terrassa/Fundacio Docència i Recerca MútuaTerrassa and the Stroke Pharmacogenomics and Genetics, Sant Pau Research Institute

MMPs and TIMPs have raised considerable interest within atherosclerosis and IS research community, as they represent an attractive target for the use of current drugs and the development of novel ones, aimed at blocking MMP activity.

Some studies have observed associations between protein plasma levels of MMPs, TIMPs, atheromatous plaque instability, stroke progression.

Here, the authors present a characterization of DNAm status of the MMP and TIMP gene families in donor-matched stable and ulcerated carotid artery atherosclerotic plaques and whole blood in atherothrombotic stroke patients and controls.

The Fernandez-Cadenas/Krupinski/Gallego-Fabrega Research Team concluded, in their Oncotarget Research Article, "we characterized MMPs and TIMPs DNAm patterns in atheromatous plaque, which led us to observe significant differences between stable and ulcerated portions in plaque tissue for MMP24 and TIMP2. Differences in MMP24 were also observed in blood samples between atherothrombotic stroke patients and healthy controls. The generalized hypermethylation found in ulcerated portions and samples from healthy controls is in line with other methylation studies. Functional analysis of the implications of methylation levels changes in MMP24 and TIMP2 have in their expression levels are needed to link this finding with the biopathology of plaque destabilization. Studies with larger sample size, to confirm our results."

Credit: 
Impact Journals LLC

Oncotarget: MicroRNA (miR) dysregulation during Helicobacter pylori-induced gastric

image: Illustration of the putative interactions between Tregs, Toll-like receptors (TLRs), and microRNAs in Helicobacter-induced inflammation, highlighting the special importance of miR-155.

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Correspondence to - Christian Prinz - christian.prinz@helios-kliniken.de

Oncotarget Volume 11, Issue 10 reported that dysregulation of noncoding micro RNA molecules has been associated with immune cell activation in the context of Helicobacter pylori-induced gastric inflammation as well as carcinogenesis, but also with downregulation of mismatch repair genes, and may interfere with immune checkpoint proteins that lead to the overexpression of antigens on gastric tumor cells.

Among the many micro RNAs involved in gastric inflammation, adenocarcinoma development and immune checkpoint regulation, mi R-155 is notable in that its upregulation is considered a key marker of chronic gastric inflammation that predisposes a patient to gastric carcinogenesis.

Dr. Christian Prinz from the Lehrstuhl für Innere Medizin1, University of Witten gGmbH, Helios Universitätsklinikum said, "Increasing evidence suggests that microRNA (miRNA) dysregulation has critical impacts on development, as well as inflammation and cancer development"

"Increasing evidence suggests that microRNA (miRNA) dysregulation has critical impacts on development, as well as inflammation and cancer development"

- Dr. Christian Prinz, Lehrstuhl für Innere Medizin1, University of Witten gGmbH, Helios Universitätsklinikum

Notably, it seems that human gastrointestinal cancer can be better classified using mi RNA expression profiles than mRNA or protein expression profiles.

Using a new bead-based flow cytometric mi RNA expression profiling method, they performed a systematic expression analysis of 217 mammalian mi RNAs from 334 samples, including multiple human cancers.

Furthermore, they successfully identified poorly differentiated tumors based on mi RNA expression profiles, whereas the classification of the same samples using messenger RNA profiles was highly inaccurate.

Many mi RNAs exhibit differential regulation in cancer, for example, mi R-34a is involved in p53-mediated apoptosis in pancreatic cancer, and nine mi RNAs are upregulated in primary breast cancer, including mi R-21, mi R-181b, and mi R-155.

The Prinz Research Team concluded in their Oncotarget Research Perspective, "clinical strategies aiming to prevent miR-155 overexpression (i. e., via silencer RNAs) may thus represent a promising method of controlling cancer growth (e. g., by allowing DNA repair), especially in pre-malignant lesions or during the early stages of gastric cancer."

Credit: 
Impact Journals LLC

How sperm unpack dad's genome so it can merge with mom's

image: Immediately after a sperm fertilizes an egg, the SPRK1 enzyme leads the first step in untangling a sperm's genome, kicking out special packing proteins called protamines, which opens up the paternal DNA and allows for major reorganization -- all in a matter of hours.

Image: 
Lan-Tao Gou

A sperm enters an egg, an embryo develops and eventually a baby is born. But back up a second -- how does the mother's half-genome actually merge with the father's half-genome to form one new human genome? Turns out researchers don't really know that much about these relatively brief, yet crucial, incipient moments in fertilization.

Researchers at University of California San Diego School of Medicine have discovered that the enzyme SPRK1 leads the first step in untangling a sperm's genome, kicking out special packing proteins, which opens up the paternal DNA and allows for major reorganization -- all in a matter of hours.

The study published March 12, 2020 in Cell.

"In this study, we were simply interested in answering a fundamental question about the beginning of life," said senior author Xiang-Dong Fu, PhD, Distinguished Professor in the Department of Cellular and Molecular Medicine at UC San Diego School of Medicine. "But in the process we've uncovered a step that might malfunction for some people, and contribute to a couple's difficulty conceiving. Now that we know SPRK1 plays a role here, its potential part in infertility can be further explored."

Sperm can be up to 20 times smaller than a normal cell in the body. And while sperm carry only half as much genetic material as a regular cell, it needs to be folded and packaged in a special way in order to fit. One way nature does this is by replacing histones -- proteins around which DNA is wound, like beads on a necklace -- with a different type of protein called protamines.

Fu's team has long studied SPRK1 for a completely different reason: its ability to splice RNA, an important step that enables the translation of genes to proteins. They previously showed that SPRK1 is over-activated in colon cancer, and they developed inhibitors to dampen the enzyme.

But back in 1999, shortly after Fu published a paper that first described the enzyme's role in RNA splicing, a research group in Greece noted similarities in the sequence of amino acid building blocks that make up SPRK1 substrates (the proteins upon which the enzyme acts) and protamine. Fu thought about it for years, but didn't have the expertise and tools to study sperm development. In 2015, Lan-Tao Gou, PhD, was interviewing for a position as postdoctoral researcher when Fu realized that with Gou's experience in spermatogenesis, he finally had the right person for the job.

"I said to Lan-Tao, let's do something nobody else is doing. I have a theory and you have the expertise," Fu said. "So we borrowed the equipment we needed and leveraged the core facilities we have here at UC San Diego.

"And, surprisingly, everything we tried supported our hypothesis -- SRPK1 leads a double life, swapping protamines for histones once sperm meets egg."

According to Fu, SPRK1 most likely started out playing this role in early embryogenesis, then later evolved the ability to splice RNA. In this way, SPRK1 gets to stick around even when it's no longer needed for embryogenesis.

Fu, Gou and team next want to determine the signals that instruct sperm to synchronize with the maternal genome.

"We have a ton of new ideas now," Fu said. "And the better we understand every step in the process of spermatogenesis, fertilization and embryogenesis, the more likely we are to be able to intervene when systems malfunction for couples struggling with reproductive issues."

Credit: 
University of California - San Diego

UM professor helps Malaysia develop conservation areas, protect species

Editor's Note: This release has been removed upon request of the submitting institution. For more information please contact Jenny Lavey, Jenny.lavey@mso.umt.edu.

Journal

Conservation Biology

DOI

10.1111/cobi.13450

Credit: 
The University of Montana

Oncotarget: Prognostic and predictive factors in pancreatic cancer

image: Summary of prognostic factors of metastatic pancreatic ductal adenocarcinoma: The figure shows on the left side the predictive markers discussed in the article and on the right the prognostic ones.

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Correspondence to - Fabrizio Citarella - f.citarella@unicampus.it

Oncotarget Volume 11, Issue 10 reported that there are not standardized predictive biomarkers able to identify patients who benefit most from treatments.

The aim of this review is to provide an overview of prognostic and predictive markers used in clinical practice and to explore the most promising fields of research in terms of treatment selection and tailored therapy in pancreatic cancer.

Dr. Fabrizio Citarella from the Department of Medical Oncology, University Campus Bio-Medico, Rome 00128, Italy said, "Pancreatic ductal adenocarcinoma (PDAC) is the 12th most frequent cancer in the world and it is the 4th cause of cancer-related death in Western Countries, with a mortality rate almost equal to its incidence and a 5-year survival rate of 5–7%."

"Pancreatic ductal adenocarcinoma (PDAC) is the 12th most frequent cancer in the world and it is the 4th cause of cancer-related death in Western Countries, with a mortality rate almost equal to its incidence and a 5-year survival rate of 5–7%."

- Dr. Fabrizio Citarella, Department of Medical Oncology, University Campus Bio-Medico

This review covers:

HISTOPATHOLOGICAL CHARACTERISTICS
MOLECULAR FACTORS
MICROSATELLITE INSTABILITY
GLYPICAN-1 (GPC1)-EXPRESSING CIRCULATING EXOSOMES
microRNA AND LONG NON-CODING RNA
CIRCURLATING TUMOR DNA AND CIRCULATING TUMOR CELLS
CA19-9
INFLAMMATORY MARKERS
NOMOGRAMS AND PROGNOSTIC SCORES
MECHANISMS OF DRUG RESISTANCE, and
BRCA 1 AND 2

The Citarella Research Team concluded, in their Oncotarget Research Article, "In a changing landscape consisting of new chemotherapy regimens, immunotherapy, and target therapies, the identification of prognostic and predictive factors is needed in view of personalized medicine which aim to choose the best therapy for the right patient. Further studies are needed to better understand pancreatic cancer biology and to identify prognostic and predictive factors, which could help clinicians to stratify pancreatic cancer patients and improve their prognosis."

Credit: 
Impact Journals LLC

Mercury's 400 C heat may help it make its own ice

video: There's ice on Mercury, where daytime temperatures reach 400 degrees Celsius, or 750 degrees Fahrenheit. A new study says that the Vulcan heat on the planet closest to the sun likely helps make some of that ice.

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NASA / Georgia Tech / Guberman / Brumfield

It is already hard to believe that there is ice on Mercury, where daytime temperatures reach 400 degrees Celsius, or 750 degrees Fahrenheit. Now an upcoming study says that the Vulcan heat on the planet closest to the sun likely helps make some of that ice.

As with Earth, asteroids delivered most of Mercury's water, the scientific consensus holds. But the extreme daytime heat could be combining with the minus 200-degree Celsius cold in nooks of polar craters that never see sunlight to act as a gigantic ice-making chemistry lab, say researchers at the Georgia Institute of Technology.

The chemistry is not too complicated. But the new study models it onto complex conditions on Mercury, including solar winds that pelt the planet with charged particles, many of which are protons key to that chemistry. The model presents a feasible path for water to arise and collect as ice on a planet rife with all the necessary components.

"This is not some strange, out of left field idea. The basic chemical mechanism has been observed dozens of times in studies since the late 1960s," said Brant Jones, a researcher in Georgia Tech's School of Chemistry and Biochemistry and the paper's first author. "But that was on well-defined surfaces. Applying that chemistry to complicated surfaces like those on a planet is groundbreaking research."

Hot, simple chemistry

Minerals in Mercury's surface soil contain what are called hydroxyl groups (OH), which are generated mainly by the protons. In the model, the extreme heat helps to free up the hydroxyl groups then energizes them to smash into each other to produce water molecules and hydrogen that lift off from the surface and drift around the planet.

Some water molecules are broken down by sunlight or rise far above the planet's surface, but other molecules land near Mercury's poles in permanent shadows of craters that shield the ice from the sun. Mercury does not have an atmosphere and thus no air that would conduct heat, so the molecules become a part of the permanent glacial ice housed in the shadows.

"It's a little like the song Hotel California. The water molecules can check in to the shadows but they can never leave," said Thomas Orlando, a professor in Georgia Tech's School of Chemistry and Biochemistry and the study's principal investigator. Orlando co-founded the Georgia Tech Center for Space Technology and Research.

"The total amount that we postulate that would become ice is 1013 kilograms (10,000,000,000,000 kg or 11,023,110,000 tons) over a period of about 3 million years," Jones said. "The process could easily account for up to 10 percent of Mercury's total ice."

The researchers will publish their results in Astrophysical Journal Letters on Monday, March 16, 2020. The research was funded by the NASA Solar System Exploration Research Virtual Institute (SSERVI) program and the NASA Planetary Atmospheres program.

Spacecraft confirms ice

In 2011, a NASA probe began orbiting Mercury and confirmed signals typical of glacial ice near the poles. The MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft sent back images and data that corroborated previous signatures for ice picked up years earlier by Earth-based radar.

The ice was dingy and lurked in permanent shadows in polar craters on Mercury, which is pocked by meteorite and asteroid scars much like Earth's moon. In fact, similarities between the two orbs, including their sizes, have led to many comparisons, including the probability of water ice on both.

Humans have found faint signs of possible ice on the moon but have found ice with near absolute certainty and in comparative abundance on Mercury. That has triggered some head-scratching: If asteroids, comets, and meteorites pummeled Mercury and the moon with water, what accounts for the difference in ice present? Did Mercury receive some water in a way that wouldn't work on the moon?

"The process in our model would not be anywhere near as productive on the moon. For one, there's not enough heat to significantly activate the chemistry," Jones said.

In a separate project, Orlando's lab is engineering a system based on the same chemistry to create water on the moon for future astronaut stations to be located there.

'Big magnetic tornados'

Protons from solar winds are more plentiful on Mercury than on Earth, where a mighty magnetic field whips solar wind particles, including protons, back out into space. Mercury's field is only about 1 percent as strong, and it swirls protons down onto the surface.

"These are like big magnetic tornados, and they cause huge proton migrations across most of the surface of Mercury over time," Orlando said.

The protons implant themselves into the soil all over the planet about 10 nanometers deep, forming in the minerals the hydroxyl groups (OH), which diffuse to the surface, where the heat does the rest.

"I would concede that plenty of the water on Mercury was delivered by impacting asteroids," Jones said. "But there's also the question of where asteroids laden with water got that water. Processes like these could have helped make it."

"A comet or asteroid actually doesn't need to carry water because the collision alone with a planet or moon can also make water," Orlando said. "Mercury and the moon are always being hit by small meteoroids, so this is happening all the time."

Credit: 
Georgia Institute of Technology

Evidence clearly favors taxing sugary drinks -- new study

image: Professor Nick Wilson
Department of Public Health
University of Otago, Wellington

Image: 
University of Otago

New Zealand should follow the UK and more than 30 other countries in introducing a tax on sugary drinks to tackle obesity and reduce deaths from chronic diseases, leading researchers say.

In a review of recent international and New Zealand research on the impact of food and beverage taxes, the researchers identify the strong level of scientific evidence showing such taxes work.

The lead author, Professor Nick Wilson from the University of Otago, Wellington, says the UK's Soft Drinks Industry Levy, known as the 'sugar tax', introduced in April 2018, has prompted manufacturers to significantly reduce the amount of sugar they add to soft drinks.

"Imposing a levy on soft drinks would be in line with the Government's priorities on improving well-being and protecting child health, and would be consistent with New Zealand's approach to taxing tobacco and alcohol to reduce the burden of harm from these products."

Another one of the authors, Professor Boyd Swinburn from the University of Auckland's School of Population Health, says dietary risk factors and high body mass index are leading causes of health loss in New Zealand, when death and disability are combined.

"In this country, around a third of adults are obese, and diet-related diseases, such as heart disease, cancer and diabetes are major causes of premature death."

Professor Swinburn says diet-related diseases are a particular burden for Māori and Pasifika and are a major cause of ethnic inequalities in health in New Zealand.

A sugar tax would help the government achieve its goals of preventing obesity in children and young people and reducing health inequities for Māori and Pacific peoples, he says.

"A tax could provide greater benefit to Māori and Pacific populations because of greater price sensitivity, and among children and young people because of their higher consumption of sugar-sweetened drinks."

The nutritional content of processed food is largely unregulated in New Zealand, with no limit to the amount of sugar, salt or saturated fat which can be added.

"None of the damage to the health of New Zealanders and the public health system costs associated with processed food are specifically paid for by the food industry, with the costs largely borne by the taxpayer-funded health system, and by the individuals and their families."

Professor Wilson says a 20 per cent tax on sugar-sweetened beverages would raise an estimated NZ$40 million a year, which could be recycled back into the community.

"The government could use the money to fund free fully-subsidised healthy breakfasts and lunches in all low-income schools and early childhood education centres, and ensure adequate drinking water fountains were provided in all public spaces."

The findings of this review form the basis of the position of the Health Coalition Aotearoa, a new non-governmental organisation which includes New Zealand health workers and researchers with expertise in nutrition.

Credit: 
University of Otago

Early blood marker may predict future risk of kidney transplant failure

Highlight

In a study of kidney transplant recipients, the composition of certain immune cells in the blood 1 year after kidney transplantation was linked with a patient's subsequent risk of kidney transplant failure.

Washington, DC (March 12, 2020) -- A newly discovered blood marker may help physicians predict which patients who recently underwent kidney transplantation are at risk of experiencing organ rejection several years later. The findings appear in an upcoming issue of JASN.

Immunosuppressive medications are essential for keeping a kidney transplant recipient's immune system from attacking the transplanted organ, but in many cases, rejection eventually occurs. Predicting kidney transplant failure may help clinicians intervene before it's too late, but this requires a better understanding of individual patients' immune responses.

By analyzing blood samples from 284 kidney transplant recipients who were followed for a median of 8.3 years, a team led by Nicolas Degauque, PhD (Université de Nantes and CHU Nantes, in France) found that the composition of immune cells called CD8+ memory T cells 1 year after kidney transplantation was linked with a patient's subsequent risk of kidney transplant failure. The investigators also found that specific CD8+ memory T cells called effector memory expressing CD45RA cells play a major role in initiating multiple immune-related processes that lead to kidney transplant failure.

"The identification of at-risk kidney transplants is based on clinical metrics already measured in the standard of care of patients and on the quantification of blood subsets of CD8+ cells that could be easily transferable in the routine monitoring of kidney transplant recipients," said Dr. Degauque. "The findings are important because early identification of at-risk kidney transplant recipients is critical to allow physicians to adapt their care by either increasing the frequency of patient monitoring or by introducing new therapeutics adapted to patients' own risks."

The results also indicate that effector memory expressing CD45RA cells may be promising targets for new treatment or prevention strategies against organ rejection.

Credit: 
American Society of Nephrology

Rates of at-risk drinking and unhealthy nutrition in Germany vary across regions

Rates of at-risk alcohol consumption are higher in the South and East of Germany, compared to the North and West, according to a study published in the open access journal BMC Public Health. However, compared to West Germany, people in East Germany eat more healthily, while rates of smoking and lack of physical activity appear to be similar across regions.

Josefine Atzendorf, the corresponding author said: "Previous studies on lifestyle risk factors generally focused on age- or gender-specific differences. However, there are indicators that smoking, nutrition, alcohol consumption and physical activity also vary across regions. We examined how these behaviours differed according to sociodemographic factors, and between North, South, East and West Germany."

Using data on 9,204 people living in Germany, the authors found that East Germany had the highest prevalence for at-risk alcohol consumption (18.3% of the population), followed by South Germany (16.7%), West Germany (14.6%) and North Germany (13.9%). At-risk alcohol consumption was defined as drinking 12 grams or more of ethanol per day for women and 24 grams or more for men. Women were less likely to drink alcohol at at-risk levels than men, but individuals with higher education were more likely to report at-risk alcohol consumption than individuals with lower education.

Unhealthy nutrition was most prevalent in West Germany (70.6%) and least prevalent in East Germany (66.7%), while prevalence of physical activity did not differ between regions. Women were more likely to report lower physical activity but less likely to report unhealthy nutrition than men. Individuals with higher education were more likely to report lower physical activity but less likely to report unhealthy nutrition than individuals with lower education.

Daily smoking, defined as having smoked at least one cigarette, cigar, pipe or cigarillo per day in the past 30 days, was equally distributed across all four regions. Women and individuals with higher education were less likely to smoke on a daily basis.

The authors used data on 5,090 women and 4,114 men aged 18 to 64 from the 2015 Epidemiological Survey of Substance Abuse, which assessed the substance use among the general population in Germany at regular intervals between 1980 and 2015. Participants were asked about their daily smoking, diet, alcohol consumption and physical activity.

The authors caution that the use of self-reported data may have introduced bias towards socially desirable answers. Hence, the prevalence of unhealthy behaviors may have been underestimated. The observational nature of the study does not allow for conclusions about cause and effect.

Josefine Atzendorf said: "Our results indicate that health-promoting strategies to reduce lifestyle risk factors in Germany are currently insufficient. Our findings could provide starting points for the development or adjustment of health policies, considering differences between regions. However, for smoking and low physical activity, where no regional differences exist, prevention and intervention measures should focus on Germany as a whole."

Credit: 
BMC (BioMed Central)

Racial and ethnic disparities in insurance access impact maternal-infant health

ANN ARBOR, Mich. -- Black, Hispanic and indigenous women are more likely to have gaps in insurance around the time of pregnancy than white women, a new study suggests.

Nearly half of all black, Hispanic, and Indigenous women had discontinuous insurance coverage between preconception and after delivering their babies compared to about a fourth of white women, according to the research in Obstetrics and Gynecology.

Spanish-speaking Hispanic women had the lowest rates of steady insurance, with nearly one in 10 not being insured at all between preconception and the postpartum period.

The study comes as women from racial and ethnic minority backgrounds face greater risks of maternal morbidity - unexpected outcomes of labor and delivery that negatively impact a woman's health - and mortality associated with childbirth. Black and indigenous women are two to four times more likely to die from pregnancy-related causes compared with white peers.

"Racial and ethnic disparities in maternal and child health outcomes are a national public health crisis," says senior author Lindsay Admon, M.D., M.Sc., an obstetrician-gynecologist at Michigan Medicine's Von Voigtlander Women's Hospital.

"We found that disruptions in insurance coverage disproportionately affect racial and ethnic minority women. In the United States, insurance coverage is an important prerequisite for accessing healthcare.

"Throughout the most critical periods of pregnancy, we identified wide racial-ethnic disparities related to women's ability to access to preconception, prenatal, and postpartum care."

Admon notes that the findings are especially relevant as the Centers for Disease Control and Prevention has identified lack of access to quality healthcare as a key contributor to pregnancy-related deaths.

Researchers analyzed data from 107,921 women in 40 states between 2015 to 2017 to establish insurance status at three at time points, including the month before conception, at the time of delivery and 60 days after birth.

Admon's previous research finds that women of color and those of Hispanic heritage had higher rates of severe birth-related health issues than non-Hispanic white women even if they were otherwise healthy.

Disparities in Insurance Access

Income gaps between white and black populations play a big factor in insurance disparities. Nearly half of black, non-Hispanic women in the study had household incomes below the federal poverty level, which were linked to higher rates of Medicaid coverage during pregnancy.

Among the biggest factors for disrupted care is Medicaid discontinuity, authors say. Pregnancy-related Medicaid coverage is only offered for up to 60 days after a baby's birth, but there are bipartisan federal and state efforts to extend the coverage to a year.

"Medicaid stability before and after pregnancy is critical for ensuring continuity of coverage and access to care for women of color," says lead author Jamie Daw, Ph.D., researcher with the Department of Health Policy and Management at Columbia University.

"Extending pregnancy Medicaid to one year after birth is likely to reduce racial disparities in insurance disruptions and ultimately, disparities in postpartum health."

Improving coverage before conception is also critical in identifying underlying health issues that may negatively affect a mother or baby's health.

"We know that complications associated with preexisting conditions chronic conditions such as heart disease, high blood pressure, and substance use are among the leading causes of maternal morbidity and mortality," says Admon, who is also a researcher at the University of Michigan Institute for Healthcare Policy and Innovation.

"It's important for women to have quality health coverage and care to manage these conditions to have the best chance of a healthy pregnancy."

"Medicaid stability before and after pregnancy is critical for ensuring continuity of coverage and access to care for women of color," says lead author Jamie Daw, Ph.D., researcher with the Department of Health Policy and Management at Columbia University.

"Extending pregnancy Medicaid to one year after birth is likely to reduce racial disparities in insurance disruptions and ultimately, disparities in postpartum health."

Improving coverage before conception is also critical in identifying underlying health issues that may negatively affect a mother or baby's health.

"We know that complications associated with preexisting conditions chronic conditions such as heart disease, high blood pressure, and substance use are among the leading causes of maternal morbidity and mortality," says Admon, who is also a researcher at the University of Michigan Institute for Healthcare Policy and Innovation.

"It's important for women to have quality health coverage and care to manage these conditions to have the best chance of a healthy pregnancy."

Credit: 
Michigan Medicine - University of Michigan

US study reports rate of suicidal ideation in children, and risk and protective factors

Around eight in every 100 children (8.4%; 673/7,994) aged 9-10 years in the USA report suicidal ideation (temporarily or regularly thinking about, considering, or planning suicide), according to a new nationally representative observational study of almost 8,000 children aged 9-10 years in the USA, published in The Lancet Psychiatry journal.

Importantly, less than two in every 100 (1.3%; 107/7,994) children aged 9-10 years reported a suicide attempt in the study, and around one in 100 (0.9%; 75/7,994) had past or current suicidal plans.

The study, which is the largest of its kind in the USA, identifies important risk and protective factors associated with childhood suicidal ideation which could be used to identify vulnerable children and plan interventions to promote mental health in school and at home.

"While a minority (around 8%) of 9-10 year olds express suicidal thoughts, the robust associations shown in this study with psychological problems (mostly anxiety and depressive problems) and family conflict provide practitioners with important information as to how they can intervene to help children and their families," says Dr Sophia Frangou from Icahn School of Medicine at Mount Sinai, USA, who co-led the research. "The same applies to the protective influences which involve higher parental supervision (ie, knowing where children are, what they are doing, and with whom) and positive school engagement, which are actionable and modifiable." [1]

She continues: "Although the best way of offering support to children is unclear, current evidence suggests that school-based programmes which aim to increase awareness, like the Mental Health Packs for Schools initiative in the UK, are likely to be successful public health interventions for reducing both suicidal behaviours and suicidal ideation." [1]

In the USA, suicide is the second leading cause of death in 10-14-year-olds, and the number of children's hospital admissions for suicidal thoughts or self-harm has more than doubled over the last decade, increasing from 0.67% in 2008 to 1.79% in 2015. However, suicidal thoughts and behaviours among children have to date received comparatively little attention compared to older age groups.

The researchers based their findings on data from 7,994 children (average age 9.9 years) taking part in the Adolescent Brain Cognitive Development (ABCD) study--which is following the largest nationally representative sample of 9-10 year-olds living in the USA [2].

To measure suicidal ideation for each child, caregivers and children were independently asked about current wellbeing and suicidal history as well as personal, family, and social characteristics using questionnaires.

Modelling was used to quantify the association between suicidal ideation and a wide array of personal, family, and social characteristics in children who had caregiver-reported (654 children) or child-reported (684 children) experiences of suicidal ideation (including 198 cases in which caregivers and children were in agreement on reports of suicide ideation), and those who had never expressed suicidal thoughts or behaviours according to caregiver and self-reports (6,854 children).

Although suicide planning and suicide attempts are relatively rare, the researchers found that factors associated with an increase in risk of suicidal thoughts included psychological problems (odds ratio [OR] 1?7-4?8, 95% CI 1?5-7?4) and exposure to child-reported family conflict (OR 1?4-1?8, 95% CI 1?1-2?5) [3].

Children, and particularly boys, who experienced suicidal ideation also reported on average spending around an hour longer using screen-based devices at weekends. However, the authors caution that more research is needed to understand whether the relationship between screen time and suicide ideation is causal (eg, the result of increased exposure to cyberbullying or negative social comparisons) or correlative (eg, linked with social withdrawal or avoidance).

Greater parental supervision (ie, knowing where children are, what they are doing, and with whom) and a child's positive view of school (ie, children who liked going to school) were identified as having a strong protective effect against suicide ideation, possibly because they can aid the development of identity, self-esteem, and resilience.

Importantly, the researchers only noted agreement between caregiver and child reports of suicide ideation in 17% of cases (198/1,140 children), indicating that suicidal thoughts and behaviours in children cannot be reliably assessed by parental report alone.

"Fears of stigmatisation, communication difficulties, and lack of social and family support may mean young children feel less comfortable talking about their mental health," explains senior co-author Dr Beatriz Luna from the University of Pittsburgh, USA. "This disconnect underscores the need for separate and independent assessment of suicide risk in children and parents." [1]

The authors note several limitations including that experience of suicidal thoughts and behaviours were based on self-reported data, which might not be accurate; and due to the cross-sectional nature of the ABCD data at this point, they are unable to address questions about the evolution of suicidal thoughts and behaviours over time. Additionally, because of the rarity of suicide attempts, it was not possible to distinguish between factors associated with suicidal thoughts and acts.

Writing in a linked Comment, lead author Dr Rory O'Connor (who was not involved in the study) from the University of Glasgow, UK, says, "If we are to develop effective suicide prevention interventions, it is essential that we identify and target these childhood risks. In particular, greater effort to protect children from early life adverse experiences is vital, given that family conflict was associated with between a 30% and 75% increased risk of suicidality, even when taking into account the effect of psychopathology...A key focus for future research should be factors that facilitate as well as impede the transition from suicidal thoughts to acts of suicide."

Credit: 
The Lancet

AMA Manual of Style updates coronavirus nomenclature

In December 2019, an outbreak of respiratory illness caused by a novel (new) coronavirus was identified in Wuhan, Hubei Province, China. Since then various organizations and media outlets have struggled to identify the respiratory illness correctly.

The AMA Manual of Style, written by editors of the JAMA Network and published by Oxford University Press, has released guidance on the terminology.

The AMA Manual of Style addresses coronavirus (CoV) in section 14.14.3, Virus Nomenclature, which includes information on Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus (SARS-CoV).

The International Committee on Taxonomy of Viruses (ICTV) Coronaviridae Study Group has determined that the new virus belongs to the existing species severe acute respiratory syndrome-related coronavirus. Thus, the new virus name recommended is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

The World Health Organization has named the new disease coronavirus disease 2019 (COVID-19).

For more information contact:
stylemanual@jamanetwork.org

Credit: 
Oxford University Press USA