Conversation cards© a useful tool in pediatric weight management — ScienceDaily

Increasing numbers of children and adolescents struggle with obesity, a challenging and complex health issue. Likewise, health care providers can find it challenging to effectively counsel families on weight management. To this end, Conversation Cards© were developed to help families think about and prioritize key challenges regarding pediatric weight management. They also create points of reference for providers, which could help to create treatment plans for families based on their priorities. Using Conversation Cards©, researchers from the University of Alberta conducted a study that reviewed the way families use the cards and how their card selections aligned with family characteristics.

Data for this cross-sectional study were retrieved from a clinic providing care for 2- to 17-year-olds with overweight or obesity. Families were introduced to Conversation Cards© at a monthly, group-based orientation session after they were referred for care by local physicians and nurse practitioners.

Among 146 participants, families selected an average of 10 cards, with an equal proportion of positive (e.g., Ongoing contact with our clinician keeps us motivated) and negative (e.g., I feel overwhelmed and lack support) statements. The most popular card choices reflected families’ readiness to make healthy changes, preference for involving children and adolescents in clinical discussions, the importance of children and adolescents in sharing their thoughts, wanting to learn how to make healthy foods fun, and desire for a specially trained fitness instructor to work with children and adolescents.

“The needs and preferences of families relating to motivation and clinical support, especially across socioeconomic groups, revealed the complexity of patient- and family-level priorities that providers can address,” lead author Maryam Kebbe, BSc, said.

Factors such as age and socioeconomic status had interesting effects on attitudes in the study. For example, compared with children, a greater proportion of adolescents disliked exercise and bought fast food in the absence of their parents. Likewise, compared with their counterparts, a greater proportion of parents with a higher level of education and lower household income reported that setting goals helped them to remain motivated; those with lower incomes also reported that their finances limited what they could do. A greater proportion of parents with a lower level of education also reported financial limitations in registering their sons and daughters in sports.

“Offering families services that align with their readiness, motivation, and ability to participate actively in pediatric weight management is ideal. Conversation Cards© may be useful to complement existing processes and procedures for both providers and families,” Kebbe added.

Although Conversation Cards© were helpful for families in establishing their priorities with health care providers, further research using this tool is needed. Several other projects are underway, including whether the Conversation Cards© can be used effectively for goal setting and enhancing motivation to change habits over time.

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Scientists begin to unravel how the protein tau transitions from a soluble liquid state to solid fibrous tangles — ScienceDaily

While much about Alzheimer’s disease remains a mystery, scientists do know that part of the disease’s progression involves a normal protein called tau, aggregating to form ropelike inclusions within brain cells that eventually strangle the neurons. Yet how this protein transitions from its soluble liquid state to solid fibers has remained unknown — until now.

Discovering an unsuspected property of tau, UC Santa Barbara physical chemist Song-I Han and neurobiologist Kenneth S. Kosik have shed new light on the protein’s ability to morph from one state to another.

Remarkably, tau can, in a complex with RNA, condense into a highly compact “droplet” while retaining its liquid properties. In a phenomenon called phase separation, tau and RNA hold together, without the benefit of a membrane, but remain separate from the surrounding milieu. This novel state highly concentrates tau and creates a set of conditions in which it becomes vulnerable to aggregation. Kosik and Han outline their discoveries in the journal PLOS Biology.

“Our findings, along with related research in neurodegeneration, posit a biophysical ‘smoking gun’ on the path to tau pathology,” said Kosik, UCSB’s Harriman Professor of Neuroscience and co-director of the campus’s Neuroscience Research Institute. “The signposts on this path are the intrinsic ability of tau to fold into myriad shapes, to bind to RNA and to form compact reversible structures under physiologic conditions, such as the concentration, the temperature and the salinity.”

The researchers found that, depending on the length and shape of the RNA, up to eight tau molecules bind to the RNA to form an extended fluidic assembly. Several other proteins like tau are known to irreversibly aggregate in other neurodegenerative diseases such as amyotrophic lateral sclerosis, more commonly known as Lou Gehrig’s disease.

“There is an interesting relationship between intrinsically disordered proteins that are predisposed to become neurodegenerative — in this case tau — and this phase separation state,” said Han, a professor in UCSB’s Department of Chemistry and Biochemistry. “Is this droplet stage a reservoir that protects tau or an intermediate stage that helps transform tau into a disease state with fibrils or both at the same time? Figuring out the exact physiological role of these droplets is the next challenge.”

Subsequent analysis will consist of an intensive search for the counterpart of tau droplets in living cells. In future work, the researchers also want to explore how and why a cell regulates the formation and dissolution of these droplets and whether this represents a potential inroad toward therapy.

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Three Gorges Dam alters downstream schistosomiasis rates — ScienceDaily

The Three Gorges Dam is a massive hydroelectric dam that spans the Yangtze River in central China and became fully operational in 2010. Ecological changes caused by the dam have altered the distribution of snails — including those that carry the Schistosoma parasites — researchers now report in PLOS Neglected Tropical Diseases.

The Three Gorges Dam (TGD) is the world’s largest power station and is known to have far-reaching impacts on the environment and ecology in a vast area of China. The Dongting Lake is the first lake on the Yangtze after the dam, and is particularly impacted. The area around the lake is also one of the most severe schistosomiasis endemic areas in China. Schistosomiasis is a parasitic disease that’s spread by infected freshwater snails.

In the new work, Hongzhuan Tan, of the Central South University, China, and colleagues collected data on snail distribution and human schistosomiasis infection in areas around the Dongting Lake and used existing hydrological data from 12 monitoring sites along the Yangtze. They then analyzed the impact of ecological changes from the dam on snail distribution and schistosomiasis rates.

Following the opening of the dam, they found, the volume of annual runoff into Dongting Lake declined by 20.85% and the sediment volume discharged into the lake declined by 73.9%. In turn, the mean density of living snails decreased by 94.35% and human rates of schistosomiasis decreased from 3.38% in 2003 to 0.44% in 2015, a reduction of 86.98%. The researchers hypothesize that low water levels in the summer and high levels in the winter led the lake to become an unsuitable environment for snails.

“Given that the impact of TGD on snail distribution and schistosomiasis prevalence in Dongting Lake area is much more complex, prolonged and in-depth studies are needed to address these issues for the effective control of snails in Dongting Lake area,” the researchers say.

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Snakebites cost Sri Lanka more than $10 million annually — ScienceDaily

Snakebites are a major public health problem in many rural communities around the world, often requiring medical care and affecting victims’ ability to work. Every year, snakebites cost the Sri Lankan government more than 10 million USD, and lead to economic loss of nearly 4 million USD for individuals, according to a new study in PLOS Neglected Tropical Diseases.

The victims of snakebites in poor rural communities in Asia, Africa, and Latin America are often young individuals who are earning a wage and have a considerable remaining life expectancy. Moreover, they often work in farming or other labor intensive jobs that they must take time off from in order to recover from a bite.

In the new work, David Lalloo, of the Liverpool School of Tropical Medicine, UK, and colleagues from the University of Kelaniya used data from a nation-wide household survey conducted in Sri Lanka in 2013 and 2013 to estimate the number of snake bites and deaths from snake bites annually. To estimate the costs of the bites, they used additional household questionnaires and information gathered from hospital cost accounting systems.

79% of victims, the study found, suffered economic loss after a snake bite, with a median out of pocket cost of $11.82 and a median loss of income of $28.57 for those employed and $33.21 for those self-employed. To put this in context, the mean per capita income per month for people living in the rural areas studied was only $74 USD. The total annual economic burden on households was $3.8 USD. In addition, each year, the bites cost the national healthcare system $10.3 million USD — which is 0.7% of the country’s total healthcare costs — and lead to more than 11,000 years’ worth of disability time, the researchers calculated. The numbers were comparable to Sri Lanka’s annual spending on meningitis and dengue.

“It is unlikely that these costs will reduce in the near future as there is no indication that the high incidence of bites is declining,” the researchers say. “Even more concerning is the economic burden that snakebite places on victims and their households… It is highly likely in Sri Lanka that snakebite drives the same catastrophic costs for the poor as many other diseases.”

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Identical twins may exchange T cells through cord blood before birth — ScienceDaily

Key immune system cells produced before birth may survive well into adulthood, according to new research published in PLOS Computational Biology.

The findings provide new insights into the immune system’s T cells, each of which possesses receptor proteins that allow it to recognize a specific pathogen. Throughout life, every person maintains a unique but highly diverse set of different T cells with receptors that recognize different pathogens. This enables protection against a wide range of diseases.

Since unique T cell receptors are created through a random process of DNA arrangement, even genetically identical twins differ in their precise set of distinct T cells. However, previous studies have shown that identical twins share more T cell receptors than would be statistically expected.

In the new study, Mikhail Pogorelyy and colleagues from the Ecole normale supérieure in Paris, and the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, address this excess of T-cell clone sharing between genetically identical twins.

The team used a statistical model of T cell receptor formation to analyze receptor DNA sequences in blood samples from adult pairs of identical twins. The analysis suggests that the degree of T-cell clone sharing between twins is greater than can be explained simply by shared genomes. Instead, the scientists propose, twin embryos may exchange T cells through cord blood before birth.

“As a result, the immune system of one twin has cells that were generated in the other twin and vice versa,” says study co-author Thierry Mora.

These findings, combined with further statistical analysis of T cell receptor DNA sequences from unrelated adults of varying ages, suggest that some T cell clones created before birth may persist in the body for about 40 years. “This longevity of clones implies that any 40 year old person can still have clones that were produced before birth,” Mora says.

These results could shed new light on the observation that the exact same T cell receptors are sometimes found in multiple unrelated adults. If T cell clones created before birth can stick around for decades, they might account for a substantial amount of shared T cells between any two unrelated people. Indeed, the diversity of T cell receptors generated before birth is known to be lower than in adults, increasing the odds of two unrelated people sharing the same receptor.

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Study finds two distinct patterns of metastatic spread in human colorectal cancer — ScienceDaily

A study led by Massachusetts General Hospital (MGH) investigators has found that the traditional model for the spread of carcinoma, the deadliest form of cancer — from the primary tumor, to nearby lymph nodes, to other organs — may not apply in all cases. In their report in the July 7 issue of Science, the researchers describe finding that, for the majority of colorectal cancer patients in the study, “distant” metastases originated directly from the primary tumor, independent of any lymph node metastases.

“Our results provide the first evidence in humans that the century-old ‘lymph node metastases are precursors of distant metastases’ model does not apply to all or even most colorectal cancers,” says lead and corresponding author Kamila Naxerova, PhD, of the Edwin L. Steele Laboratories for Tumor Biology in the MGH Department of Radiation Oncology. “These findings fill an important gap in our knowledge of metastatic disease evolution and have the potential to guide improvements in the clinical management of lymph node metastases.”

The current study is a follow-up to a 2014 report in which Naxerova and her colleagues described a simple assay that could reveal evolutionary relationships between tumors at various sites in a patient’s body. Based on analysis of small, mutation-prone segments of the genome called polyguanine (poly-G) repeats, that study found that relationships between primary and metastatic tumors were different in each case — for example, in some patients metastatic spread occurred early and in others late in tumor development. The assay was also able to identify specific areas within a primary tumor that had been the source of specific metastases, based on their genetic profiles.

Treatment for most solid tumors now incorporates what are called TNM — primary tumor (T), nodal metastasis (N), and distant metastasis (M) — staging schemes. Patients with lymph node metastases are known to have a higher likelihood of developing distant metastases, implying a link between the two. But in several recent clinical trials the removal of metastatic lymph nodes did not always improve patient survival, casting doubt on the relationship between nodal and distant metastasis. To better understand relationships between primary tumors and the two types of metastases, the researchers used poly-G typing to analyze more than 200 tissue samples of primary tumors, lymph node metastases and distant metastases from 17 patients with colorectal cancer.

In 35 percent of these patients, the results indicated that both lymph node and distant metastases had arisen from the same cell type in the primary tumor, findings compatible with the scenario of spread from the primary tumor to lymph nodes and then to distant sites. However, in 65 percent of patients, poly-G typing showed that lymph node and distant metastases cell types were different and matched different cell types within the primary tumor, indicating independent origins for these metastasis types.

Naxerova says, “We now suspect that lymph node metastases simply indicate the presence of an aggressive primary tumor, rather than being directly responsible for the formation of distant metastases. Now we need to investigate whether clinical outcomes for patients whose lymphatic and distant metastases have common origins are different from those of patients whose metastases have distinct evolutionary origins. If there is a difference, our assay might be a useful prognostic test in the future.” Naxerova is a Research Fellow at the Edwin L. Steele Laboratories and at the Division of Genetics at Brigham and Women’s Hospital and Harvard Medical School.

Rakesh K. Jain, PhD, director of the Steele Labs, Cook Professor of Radiation Oncology (Tumor Biology) at Harvard Medical School, and senior author of the Science paper, says, “Lymph nodes are usually considered as contributors to distant metastases. Yet multiple retrospective and prospective studies have shown that complete dissection of lymph nodes does not confer survival advantage in a number of malignancies. Our study provides the first direct genetic evidence towards resolving this enigma.”

Study co-author Jochen K. Lennerz, MD, PhD, of the Center for Integrated Diagnostics in the MGH Department of Pathology, adds, “Typing, grading, and staging — our traditional cancer assessment tools — cannot account for the relationships between cancer at multiple sites. Now, we have a new, effective way of looking at disseminated cancer. Given that this test is cost-effective, we are excited to bring it to the clinic as soon as possible.”

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Exposing newborn mice to general anesthetic disrupts brain development — ScienceDaily

The U.S. Food and Drug administration (FDA) has recently issued a safety advisory warning that exposure to anesthetic and sedative drugs during the period of time between the third trimester of prenatal development and the first three years of life may have lasting adverse effects on cognitive function. New research publishing July 6 in the open access journal PLOS Biology by Eunchai Kang, David Mintz and colleagues now shows that early postnatal mice exposed to isoflurane — a standard and widely used inhaled general anesthetic agent — leads to chronic, abnormal activation of the mTOR pathway, a signaling system critical for normal brain development.

The researchers, based in The Johns Hopkins University School of Medicine, Baltimore, focused on the hippocampus, a brain region that is critical for learning and memory. The hippocampus contains a large number of neurons that develop in the early postnatal period, and which might thus vulnerable be to perturbation by anesthetic exposure.

15 day-old mice were exposed to clinically relevant doses of isoflurane and the effects on the subsequent development of the hippocampus were recorded. The structures of one class of neurons (the dentate gyrus granule cells) were found to be substantially altered. Specifically, the branches or dendrites of the neurons were almost twice the length of those in untreated animals, suggesting that the anesthetic caused an abnormal acceleration in their growth. In addition they saw a significant reduction in the number of mature dendritic spines — structures on the dendrites where synapses are found.

To see whether these changes were associated with an effect on learning, the treated and untreated mice were subjected to two standard behavioral tests (an object-place recognition test and a Y-maze test). The isoflurane-treated mice performed significantly worse in both tests.

The authors went on to show that pharmacologic inhibition of the mTOR pathway with the drug rapamycin protects mice from both the abnormal structural changes in the brain and the learning deficits associated with isoflurane exposure. This study thereby links the adverse effects of early developmental anesthetic exposure with mTOR, which in turn has been previously implicated in numerous neurodevelopmental cognitive disorders including autism and Fragile-X mental retardation, thus suggesting a molecular mechanism by which anesthetics might have adverse effects on brain development.

The FDA advisory warning is based on the findings of both human and animal studies. Some epidemiological research conducted in human populations reveals a correlation between exposure to anesthesia and worsened performance on school assessments, an increase in billing codes relevant to learning disorders, and deficits in neuropsychological testing. These findings are difficult to interpret by themselves, given that exposure to general anesthesia implies that an individual has had a prior medical condition and has undergone surgery. However, when the epidemiological findings are considered along with rodent studies such as this one, which unequivocally demonstrate that exposure to anesthetics during key periods of brain development results in worsened performance on behavioral tests of learning and memory, a causal link in humans seems likely. The FDA safety advisory calls for further research on this topic to clarify the risk to patients.

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New method to fight malaria found by scientists — ScienceDaily

Scientists have discovered a new way to slow down malaria infections, providing a possible new target for antimalarial drugs. The team are already working with pharmaceutical companies to use this knowledge to develop new antimalarials — an important step in the battle against drug resistant malaria.

When malaria parasites invade red blood cells, they form an internal compartment in which they replicate many times before bursting out of the cell and infecting more cells. In order to escape red blood cells, the parasites have to break through both the internal compartment and the cell membrane using various proteins and enzymes.

Scientists at the Francis Crick Institute and The London School of Hygiene & Tropical Medicine have identified a key protein involved in this process. Disrupting this protein reduces the efficiency of parasite escape, slowing down the rate of infection. The research, published in PLOS Pathogens was funded by Cancer Research UK, the Medical Research Council and Wellcome.

“The parasite sits in its internal compartment inside the cell, surrounded by lots of proteins, a bit like a baby surrounded by amniotic fluid,” says Mike Blackman, Group Leader at the Francis Crick Institute. “We focused on the most common protein, known as SERA5, assuming that it probably has an important role since there is so much of it.”

The team used genetic tools to knock out the gene responsible for producing SERA5 in malaria parasites and then took time-lapse video of the cells under a microscope. They found that the parasites broke through the membranes faster than normal but many got stuck on their way out, meaning that they were less likely to invade other red blood cells.

“Malaria parasites don’t survive for long outside red blood cells, so if they get stuck on their way out, they might die before they have a chance to infect another cell,” says Christine Collins, researcher at the Francis Crick Institute and first-named author of the paper. “We found that parasites lacking SERA5 were about half as efficient as normal parasites at escaping and infecting new cells.”

The team are now working with GSK to see if SERA5 or one of the enzymes that it controls could be a potential drug target.

“Drug resistant malaria is a huge problem, so there is a real push to develop new drugs that work in a different way,” says Mike. “None of the current antimalarials work by preventing the parasites from escaping red blood cells, so we think that the proteins and enzymes that help the parasites break free could be valuable new targets that we can design drugs for.”

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Games found to improve conceptual math skills, but gains may not carry over to primary school — ScienceDaily

What is the best way to help poor schoolchildren succeed at math? A study co-authored by researchers at MIT, Harvard University, and New York University now sheds light on the ways preschool activities may — or may not — help children develop cognitive skills.

The study, based on an experiment in Delhi, India, engaged preschool children in math games intended to help them grasp concepts of number and geometry, and in social games intended to help them cooperate and learn together.

The results contained an unexpected wrinkle. Children participating in the math games did retain a superior ability to grasp those concepts more than a year later, compared to children who either played only the social games or did not participate. However, the exercises did not lead to better results later, when the children entered a formal classroom setting.

“It’s very clear you have a significant improvement in the math skills” used in the games, says Esther Duflo, the Abdul Latif Jameel Professor of Poverty Alleviation and Development Economics at MIT and co-author of the study. “We find that the gains are persistent … which I think is quite striking.”

However, she adds, by the time the children in the study were learning formal math concepts in primary school, such as specific number symbols, the preschool intervention did not affect learning outcomes.

“All the kids [in primary school] had learned, but they had learned [those concepts] equally,” says Duflo, who is a co-founder of MIT’s Abdul Latif Jameel Poverty Action Lab (J-PAL), which conducts field experiments, often in education, around the globe.

A paper detailing the results of the study, “Cognitive science in the field: A preschool intervention durably enhances intuitive but not formal mathematics,” is being published in the journal Science.

The authors are Duflo; Moira R. Dillon, an assistant professor in New York University’s Department of Psychology; Harini Kannan, a postdoc at J-PAL South Asia; Joshua T. Dean, a graduate student in MIT’s Department of Economics; and Elizabeth Spelke, a professor of psychology and researcher at the Laboratory for Developmental Studies at Harvard University.

It’s a numbers game

The results bear on the question of how early-childhood educational interventions can help poor children access the same educational concepts that more privileged children have before entering primary school.

Spelke, an expert in cognitive development among children, notes that around age 5, children “transition from developing knowledge in a common-sense, spontaneous manner, to going to school, where they have to start grappling with formal subjects and building formal skills.” She adds that this can be a highly challenging transition for children living in poverty whose parents had no schooling themselves.

To address that, the researchers developed a field experiment involving 1,540 children, who were 5 years old on average and enrolled in 214 Indian preschools.

Roughly one-third of the preschool children were put in groups playing math games exposing them to concepts of number and geometry. For instance, one game the children played allowed them to estimate numbers on cards and sort the cards on that basis.

Another one-third of the preschool children played games that focused on social content, encouraging them to, for instance, estimate the intensity of emotional expressions on cards and sort the cards on that basis. In all, the games were “fun, fast-paced, and social” and “encouraged a desire to play together,” Dillon says.

Meanwhile, the final one-third of the preschoolers had no exposure to either type of game; these children formed another control group for the study.

The researchers then followed up on the abilities of children from all three groups, soon after the intervention, as well as six and 12 months later. They found that even after the first year of primary school, children who had played the math games were better at the skills that those games developed, compared to children from the other groups. The intervention using social games had effects on social skills but did not produce a comparable effect on math skills; the effects of the math games were specific to their math content.

Despite these effects, the early exposure to numerical concepts such as one-to-one correspondence, and geometrical concepts such as congruence and parallelism did not produce an advantage for the first group of students when it came to achievement in primary school. As the paper states, “Although the math games caused persistent gains in children’s non-symbolic mathematical abilities, they failed to enhance children’s readiness for learning the new symbolic content presented in primary school.”

Not adding up

The researchers have been analyzing why the intervention did not produce improvements in school results. One possibility, Duflo observes, is that children in Delhi primary schools learn math in a rote style that may not have allowed the experiment’s set of games to have an effect. Kids in these schools, she observes, “are [only] learning to sing ‘1 times 1 is 1, 1 times 2 is 2.'” For this reason, Duflo notes, the greater understanding of the concepts provided by the preschool math games might be more beneficial when aligned with a different kind of curriculum.

Or, Spelke puts it, “the negative thing that we learned” from the study is that lab work is not necessarily “sufficient to establish what actually causes knowledge to grow in the mind of a child, over timespans of years in the environments in which children live and learn.”

With that in mind, the research team is designing follow-up studies in which the games will segue more seamlessly into the curriculum being used in a particular school district.

“We want to include in the games themselves some element of bridging between the intuitive knowledge of mathematics and the formal knowledge they will be actually exposed to,” Duflo says. J-PAL is currently engaged in developing projects along these lines in both India and the U.S.

The larger goal of helping disadvantaged preschool children remains intact, Duflo emphasizes: “If we could take the poorest kids and instead of sending them to school with a [learning deficit], because they haven’t been to preschool or been to very good preschools, or their parents have not been able to help them out in the schoolwork, why couldn’t we try to use the best cognitive science available and bring them to school with a slight advantage?”

Ceria-zirconia nanoparticles as enhanced multi-antioxidants are effective in sepsis treatment — ScienceDaily

During sepsis, cells are swamped with reactive oxygen species generated in an aberrant response of the immune system to a local infection. If this fatal inflammatory path could be interfered, new treatment schemes could be developed. Now, Korean scientists report in the journal Angewandte Chemie that zirconia-doped ceria nanoparticles act as effective scavengers of these oxygen radicals, promoting a greatly enhanced surviving rate in sepsis model organisms.

Sepsis proceeds as a vicious cycle of inflammatory reactions of the immune system to a local infection. Fatal consequences can be falling blood pressure and the collapse of organ function. As resistance against antibiotics is growing, scientists turn to the inflammatory pathway as an alternative target for new treatment strategies. Taeghwan Heyon from Seoul National University, Seung-Hoon Lee at Seoul National University Hospital, South Korea, and collaborators explore ceria nanoparticles for their ability to scavenge reactive oxygen species, which play a key role in the inflammatory process. By quickly converting between two oxidation states, the cerium ion can quench typical oxygen radical species like the superoxide anion, the hydroxyl radical anion, or even hydrogen peroxide. But in the living cell, this can only happen if two conditions are met.

The first condition is the size and nature of the particles. Small, two-nanometer-sized particles were coated by a hydrophilic shell of poly(ethylene glycol)-connected phospholipids to make them soluble so that they can enter the cell and remain there. Second, the cerium ion responsible for the quenching (Ce(3+)) should be accessible on the surface of the nanoparticles, and it must be regenerated after the reactions. Here, the scientists found out that a certain amount of zirconium ions in the structure helped, because “the Zr(4+) ions control the Ce(3+)-to-Ce(4+) ratio as well as the rate of conversion between the two oxidation states,” they argued.

The prepared nanoparticles were then tested for their ability to detoxify reactive oxygen species, not only in the test tube, but also in live animal models. The results were clear, as the authors stated: “A single dose of ceria-zirconia nanoparticles successfully attenuated the vicious cycle of inflammatory responses in two sepsis models.” The nanoparticles accumulated in organs where severe immune responses occurred, and they were successful in the eradication of reactive oxygen species, as evidenced with fluorescence microscopy and several other techniques. And importantly, the treated mice and rats had a far higher survival rate.

This work demonstrates that other approaches in sepsis treatment than killing bacteria with antibiotics are possible. Targeting the inflammatory signal pathways in macrophages is a very promising option, and the authors have shown that effective scavenging of reactive oxygen species and stopping inflammation is possible with a suitably designed chemical system like this cerium ion redox system provided by nanoparticles.

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