Possible early diagnosis of autism spectrum disorder — ScienceDaily

Measuring a set of proteins in the blood may enable earlier diagnosis of autism spectrum disorder (ASD), according to a study from the Peter O’Donnell Jr. Brain Institute at UT Southwestern Medical Center.

The research found that the levels of two proteins previously identified as potential markers for ASD could help scientists accurately diagnose the disorder in approximately 75 percent of the children studied. When the two proteins are measured together, the diagnostic accuracy increased to 82 percent.

The study published in the Journal of Neuroinflammation is among several recent and ongoing efforts to improve early diagnosis of ASD by shifting focus to biological measurements instead of behavioral symptoms.

Progress in this area could lead to earlier intervention and help limit the effects of the disorder, said Dr. Dwight German, study senior author and Professor of Psychiatry at UT Southwestern.

“ASD is a very heterogeneous disorder, and if we can identify biomarkers for even a subgroup of ASD patients, then that would be extremely helpful not only for early diagnosis but also for the development of therapeutics,” said Dr. German, whose latest research builds upon an ASD finding published last year in Scientific Reports.

ASD affects approximately 1 in 68 children in the U.S. The neurodevelopmental disorder is characterized by social interaction and communication challenges, and restricted and repetitive patterns of behavior.

Most cases are not diagnosed until about age 4, when communication and social disabilities become apparent. However, recent research offers hope that detection may be possible by age 1 by measuring brain growth.

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Education, access to seats might be better route, study author says — ScienceDaily

Laws that require increasingly older kids to sit in car safety seats appear to have limited impact, new research has found.

The same parents who already were buckling up kids appear most likely to switch to safety seats, leaving the same number of kids unrestrained, found a study published in the Journal of Policy Analysis and Management.

“These laws can be very appealing for legislators to pass, but our research calls into question their value,” said Lauren Jones, lead researcher and assistant professor of consumer sciences at The Ohio State University.

“Our study suggests that safety-conscious parents are likely to do what makes their child the safest but these laws don’t have much effect on other parents.”

Furthermore, higher fines (which reached as much as $500 as of 2016) didn’t appear to make much difference in raising the likelihood parents and other drivers complied with the laws, the study found.

In the last four decades, laws throughout the United States have steadily increased mandatory safety seat restraint ages. In the 1980s and 1990s, safety seat laws were the norm for kids up to age 2 or — at most — 3. By 2012, the average upper age requirement was 6 years old.

About 17 percent of children 7 years old and younger were in car safety seats before new laws expanded age requirements. That percentage jumped from 27 percent to almost half after stricter laws took effect, the researchers found.

But the percentage of unrestrained children — those with neither a seatbelt on nor strapped into a car seat — barely moved.

The new study found evidence that the laws saved lives, but that data was limited, Jones said. A best-case estimate showed that between one and 39 children may have survived annually because of safety seats.

“I think the laws have probably reduced fatalities, but probably not as much as most parents would assume,” Jones said. “Thank goodness childhood car crash deaths are something that happens relatively infrequently, but that also makes it harder to evaluate.”

Importantly, this study did not examine injuries or severity of injuries before and after passage of stricter laws. It’s possible that children’s injuries have declined because of more widespread use of safety seats, Jones said.

Jones and Nicolas Ziebarth of Cornell University used a national database of fatal crashes from 1975 to 2011 to examine “before” and “after” restraint use and fatalities.

To improve the quality of their evaluation, they analyzed law-mandated child safety seat use against use in three other groups: children in different states in the same year, children in the same state in different years and older children in the same state during the same year.

Regardless of the analysis, there was no evidence that safety seat laws significantly changed the percentage of children who go unrestrained, prompting Jones to conclude that resources might be better spent elsewhere.

The research estimates the net annual cost of the safety seat laws at $377 million. The researchers factored in 39 saved lives at an estimated value of $390 million per year and a cost of $200 per safety seat, or $767 million a year. Their rough estimate does not include other potential safety benefits, including reduced injury rates.

“It’s not a costless piece of legislation, especially for low-income families,” Jones said. “Education, particularly of young parents, and resources to help them afford seats could be more impactful policy tools.”

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Even perfectly clean hands can lead to MRSA transmission in NICU babies — ScienceDaily

Even if hospital workers practice perfect hand hygiene, MRSA can still spread among babies in the NICU, according to new research led by a Drexel University researcher.

Neal D. Goldstein, PhD, assistant research professor in the Dornsife School of Public Health, and his team of researchers decided to look at how the complex patient care environment of a neonatal intensive care unit (NICU) may lead to MRSA transmission. Focusing on hand hygiene — a top indicator of whether infections might spread in hospitals — the researchers examined transmission from baby to baby, with the hospital workers that come into contact with newborns standing as the link.

And as it turns out, even theoretically perfect compliance with hand hygiene won’t completely eliminate the chance for MRSA to spread: the averaged risk reduction was 86 percent.

“The biggest implication is that hospitals should not just rely upon hand hygiene alone for protecting patients from becoming colonized and possibility infected with a difficult-to-treat organism,” Goldstein said. “Rather, infection control is a multi-pronged strategy. It can incorporate early detection and measures to mitigate spread that include possible decolonization or using an antibiotic to treat a patient even before infection.”

The study, which was published in Infection Control & Hospital Epidemiology, used Methicillin-resistant Staphylococcus aureus (MRSA), a difficult to treat pathogen that can be deadly for people with weak or underdeveloped immune systems, as its subject.

“We wanted to focus on an organism that is frequently encountered in hospital environments,” Goldstein said. “In our vulnerable population of babies in the ICU, MRSA is of particular importance because about one third of babies that are colonized will go on to develop an invasive infection.”

In his simulation study, based out of Christiana Care’s NICU (in Newark, Delaware), Goldstein discovered that even if health workers had absolutely perfect hand hygiene, just under one in every 100 contacts between a baby and a hospital worker could still result in a MRSA transmission. During the average nine day stay, an infant is likely to have about 250 contacts with NICU workers that carry risk for MRSA transmission. While each contact is an opportunity for hygiene compliance, it is also potential for hygienic practices to break down.

“This sheds light on just how complex the patient care environment of a NICU is,” Goldstein said. “There are so many opportunities to potentially pass an organism between healthcare workers and their patients.”

Although it seemed that MRSA could not be completely wiped out through perfect hand hygiene, the study did show that the better hand hygiene was, the more it cut down on the spread of MRSA. The effect never quite leveled off, but continued to get better as hygiene levels improved.

When the team divided levels of hand hygiene into quartiles, the lowest level of cleanliness was associated with an averaged 29 percent decrease in MRSA prevalence when compared to no hand washing. And when the team looked at the two quartiles considered within the average range for hand hygiene of hospital workers, they found it correlated with a decrease in MRSA ranging between 51 and 67 percent.

However, having multiple lines of defense remains important.

“I think the reality is that infection control is not, nor can ever be, perfect,” Goldstein said. “You may follow all guidelines and suggested procedures, have 100 percent adherence to these interventions, and patients can still become colonized and possibly infected.”

So beyond hospitals practicing good hand hygiene and antimicrobial management, Goldstein suggests that efforts by people beyond hospital workers, including parents, visitors and the patients themselves (the non-infant patients, of course) can make a difference.

“We can follow hygiene procedures, use gowns or gloves as needed, keep a clean environment, not bring in possible fomites such as cell phones, watches, or jewelry, and be a watchdog for the hospital, requesting that healthcare workers do hand hygiene if we don’t see it being done,” Goldstein said. “Outside the hospital, patients and parents can be more vigilant in requesting and using antibiotics appropriately so as not to give rise to antimicrobial resistant organisms. We’re all participants in infection control, not just the clinicians.”

French scientists share preliminary findings about how the human body adapts to vibrations experienced while running — ScienceDaily

Running is one of the most popular sports in the world. More than 110 million people in the EU and the U.S. reported running recreationally in recent surveys; billions of dollars are spent globally each year to purchase running apparel and participate in races.

However, the sport’s devotees suffer from a surprisingly high rate of injury. According to one peer-reviewed medical study, nearly half of all recreational runners who train regularly will suffer from running-related injuries in a given year. One of the reasons for these injuries is that runners endure many shocks from the impact of running, and these cause vibrations that travel from the foot throughout the entire body.

Delphine Chadefaux, a post-doctoral researcher who focuses on acoustics and biomechanics, studies these repetitive shocks and investigates how runners adapt their running patterns according to running conditions. Chadefaux will share some of the insights from her research during Acoustics ’17 Boston, the third joint meeting of the Acoustical Society of America and the European Acoustics Association being held June 25-29, in Boston, Massachusetts.

“The way runners manage the three-dimensional components of the vibrations, especially in terms of frequency, is not well understood. It’s very difficult to measure the vibrations accurately,” Chadefaux explained. “The study looked at which biomechanical parameters runners adapt to tune the shock-induced vibrations according to different running conditions.”

Chadefaux measured the kinematics of the runners with a motion capture system. The vibrations were measured with small accelerometers placed on the skin at various points of interest, such as at the foot, knee, shank and hip.

“We wanted to understand how the vibrations were propagating and how the human body was adapting to them,” Chadefaux said. “While taking these measurements, runners were running on an indoor surface under controlled conditions. In the future, we would like to experiment with more realistic conditions by carrying out the experiment outdoors.”

“Preliminary results revealed that at various speeds the human body is changing to adapt to these vibrations and stabilize the energetics that are propagating to the upper part of the body. Whether you run slowly or quickly, the same processes are still at work to protect the upper area of the body,” Chadefaux said. “With that said, these are still early findings and more research is required to confirm them.”

The study can help fill an important gap in the research literature, according to Chadefaux. “Many of the studies involved in running or shoe development do not focus enough on shock propagation,” Chadefaux said. “We would eventually like to use the insights that we garner to advance the collective understanding of how to prevent running injuries and design better running shoes.”

Conducting the study was not without its challenges. There are many different techniques that had to be integrated so that researchers could gather kinematic, vibrational, electromyographic and dynamics data.

“The other challenge is the diversity of the runners’ bodies. Each one is fundamentally unique. Certainly, this makes the work a lot more interesting. When you try, however, to understand the significance that these differences might play in injury, it becomes apparent that the human body is like an experimental black box. You just can’t open it up and take it apart,” Chadefaux said.

Chadefaux’s work is not limited to running. She and her colleagues are also studying tennis, investigating how vibration induced by the tennis ball’s contact with the racket propagates through the human body.

“While we are in the initial stages of this work, we would like to understand more about the control of the human neuro-musculoskeletal system when exposed to vibration. It would be valuable to distinguish the relevant features of the vibration content which may provide a noteworthy feedback on performance, from the noisy part which can lead to injuries.”

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Cancer researchers overestimate reproducibility of preclinical studies — ScienceDaily

Cancer scientists overestimate the extent to which high-profile preclinical studies can be successfully replicated, new research publishing June 29 in the open access journal PLOS Biology by Jonathan Kimmelman and colleagues from McGill University suggests.

The findings are based on a survey in which both experts and novices were asked to predict whether mouse experiments in six prominent preclinical cancer studies conducted by the Reproducibility Project: Cancer Biology (RP:CB) would reproduce the effects observed in original studies.

On average, the researchers forecasted a 75% probability of replicating statistical significance, and a 50% probability of reproducing the same size effect as in the original study. Yet according to these criteria, none of the six studies already completed by the Reproducibility Project (the last of which was published this week in eLife) showed the same results previously reported.

One possible explanation for the optimism is that cancer scientists overestimate the replicability of major reports in their field. Another is that they underestimate the logistical and methodological complexity of independent laboratories repeating these techniques.

The work follows on numerous reports exploring biomedicine’s so-called reproducibility crisis. In the last 10 or 15 years, there have been mounting concerns that some of the techniques and practices used in biomedical research lead to inaccurate assessments of a drug’s clinical promise.

Given that not all studies reproduce, Kimmelman and his team wondered if cancer experts could at least sniff out which studies would not easily replicate. The finding that cancer researchers’ ability to do so “was really limited” suggests that there may be inefficiencies in the process by which science “self-corrects.”

There is however strong community concern that, due to process-related issues and potential methodological differences, the replication studies themselves may not be an entirely reliable measure of replication outcome. Kimmelman emphasizes that the findings don’t indicate that scientists who participated in the study don’t understand what’s going on their field — nor does it diminish the importance of funding research and making policy on the basis of scientific consensus. Some scientists were highly accurate in their predictions, and participants were new to forecasting, which can be challenging.

The results do, however, raise the possibility that training might help many scientists overcome certain cognitive biases that affect their interpretation of scientific reports.

“If the research community believes a finding to be reliable, it might start building on that finding only to later discover the foundations are rotten. If scientists suspect a claim to be spurious, they are more likely to test that claim directly before building on it.”

“This is the first study of its type, but it warrants further investigation to understand how scientists interpret major reports,” Kimmelman says. “I think there is probably good reason to think that some of the problems we have in science are not because people are sloppy at the bench, but because there is room for improvement in the way they interpret findings.”

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Elephantiasis on the decline in Cameroon — ScienceDaily

Lymphatic filariasis — a parasitic infection commonly known as elephantiasis — is among the 10 neglected tropical diseases that the World Health Organization (WHO) is aiming to eliminate by 2020. In Cameroon, large-scale annual mass drug administration efforts are successfully curbing rates of LF, researchers now report in PLOS Neglected Tropical Diseases.

In 2000, more than 120 million people were infected with LF, and 40 million were disfigured and incapacitated by the disease. The WHO has proposed a strategy to eliminate LF which includes mass drug administrations and disability prevention programs. In Cameroon, annual drug administrations of ivermectin and albendazole began in 2008.

In the new work, Joseph Kamgno, of the University of Yaoundé, Cameroon, and colleagues studied 5,292 children aged 5-8 from 97 communities in five health districts in Cameroon that achieved at least 65% drug coverage in six annual mass drug campaigns. The communities were assigned into three evaluation units based on WHO criteria. A blood sample from each child was tested for LF.

In the three evaluation units, 2, 8, and 11 cases of LF were detected, giving rates of 0.13%, 0.57%, and 0.45%. These rates were below WHO critical cut-off thresholds — which would be 18 cases in each evaluation unit — for stopping treatment.

“These results support the cessation of mass drug administration in these implementation units, but this decision needs further thinking,” the researchers say. It is possible for disease transmission to continue even when prevalence is very low, they add. “Post-mass drug administration surveillance activities should be organized to evaluate whether recrudescence can occur.”

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Neurotech experts call for new measures to ensure brain-controlled devices are beneficial and safe — ScienceDaily

As brain-controlled robots enter everyday life, an article published in Science states that now is the time to take action and put in place guidelines that ensure the safe and beneficial use of direct brain-machine interaction.

Accountability, responsibility, privacy and security are all key when considering ethical dimensions of this emerging field.

If a semi-autonomous robot did not have a reliable control or override mechanism, a person might be considered negligent if they used it to pick up a baby, but not for other less risky activities. The authors propose that any semi-autonomous system should include a form of veto control — an emergency stop — to help overcome some of the inherent weaknesses of direct brain-machine interaction.

Professor John Donoghue, Director of the Wyss Center for Bio and Neuroengineering in Geneva, Switzerland said: “Although we still don’t fully understand how the brain works, we are moving closer to being able to reliably decode certain brain signals. We shouldn’t be complacent about what this could mean for society. We must carefully consider the consequences of living alongside semi-intelligent brain-controlled machines and we should be ready with mechanisms to ensure their safe and ethical use.”

“We don’t want to overstate the risks nor build false hope for those who could benefit from neurotechnology. Our aim is to ensure that appropriate legislation keeps pace with this rapidly progressing field.”

Protecting biological data recorded by brain-machine interfaces (BMIs) is another area of concern. Security solutions should include data encryption, information hiding and network security. Guidelines for patient data protection already exist for clinical studies but these standards differ across countries and may not apply as rigorously to purely human laboratory research.

Professor Niels Birbaumer, Senior Research Fellow at the Wyss Center in Geneva (formerly at University of Tübingen, Germany) said: “The protection of sensitive neuronal data from people with complete paralysis who use a BMI as their only means of communication, is particularly important. Successful calibration of their BMI depends on brain responses to personal questions provided by the family (for example, “Your daughter’s name is Emily?”). Strict data protection must be applied to all people involved, this includes protecting the personal information asked in questions as well as the protection of neuronal data to ensure the device functions correctly.”

The possibility of ‘brainjacking’ — the malicious manipulation of brain implants — is a serious consideration say the authors. While BMI systems to restore movement or communication to paralysed people do not initially seem an appealing target, this could depend on the status of the user — a paralysed politician, for example, might be at increased risk of a malicious attack as brain readout improves.

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Controlling a single brain chemical may help expand window for learning language and music — ScienceDaily

Learning language or music is usually a breeze for children, but as even young adults know, that capacity declines dramatically with age. St. Jude Children’s Research Hospital scientists have evidence from mice that restricting a key chemical messenger in the brain helps extend efficient auditory learning much later in life.

Researchers showed that limiting the supply or the function of the neuromodulator adenosine in a brain structure called the auditory thalamus preserved the ability of adult mice to learn from passive exposure to sound much as young children learn from the soundscape of their world. The study appears June 30 in the journal Science.

“By disrupting adenosine signaling in the auditory thalamus, we have extended the window for auditory learning for the longest period yet reported, well into adulthood and far beyond the usual critical period in mice,” said corresponding author Stanislav Zakharenko, M.D., Ph.D., a member of the St. Jude Department of Developmental Neurobiology. “These results offer a promising strategy to extend the same window in humans to acquire language or musical ability by restoring plasticity in critical regions of the brain, possibly by developing drugs that selectively block adenosine activity.”

The auditory thalamus is the brain’s relay station where sound is collected and sent to the auditory cortex for processing. The auditory thalamus and cortex rely on the neurotransmitter glutamate to communicate. Adenosine was known to reduce glutamate levels by inhibiting this neurotransmitter’s release. This study also linked adenosine inhibition to reduced brain plasticity and the end of efficient auditory learning.

Researchers used a variety of methods to demonstrate that reducing adenosine or blocking the A1 adenosine receptor that is essential to the chemical messenger’s function changed how adult mice responded to sound.

Much as young children pick up language simply by hearing it spoken, researchers showed that when adenosine was reduced or the A1 receptor blocked in the auditory thalamus, adult mice passively exposed to a tone responded to the same tone stronger when it was played weeks or months later. These adult mice also gained an ability to distinguish between very close tones (or tones with similar frequencies). Mice usually lack this “perfect pitch” ability.

Researchers also showed that the experimental mice retained the improved tone discrimination for weeks.

“Taken together, the results demonstrated that the window for effective auditory learning re-opened in the mice and that they retained the information,” Zakharenko said.

Among the strategies researchers used to inhibit adenosine activity was the experimental compound FR194921, which selectively blocks the A1 receptor. If paired with sound exposure, the compound rejuvenated auditory learning in adult mice. “That suggests it might be possible to extend the window in humans by targeting the A1 receptor for drug development,” Zakharenko said.

Zakharenko and his colleagues also linked the age-related decline in ease of auditory learning to an age-related increase in an enzyme (ecto-5′-nucleotidase) involved in adenosine production in the auditory thalamus. Researchers reported that mature mice had higher levels than newborn mice of the enzyme and adenosine in the auditory thalamus. Deletion of this enzyme returned the adenosine level in adult mice to the level of newborn mice. Therefore, researchers are currently looking for compounds that target ecto-5′-nucleotidase as an alternative approach for extending the window of auditory learning.

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New study reveals key steps in CRISPR-Cas3 function at near-atomic resolution — ScienceDaily

Harvard Medical School and Cornell University scientists have generated near-atomic resolution snapshots of CRISPR that reveal key steps in its mechanism of action. The findings, published in Cell on June 29, provide the structural data necessary for efforts to improve the efficiency and accuracy of CRISPR for biomedical applications.

Through cryo-electron microscopy, the researchers describe for the first time the exact chain of events as the CRISPR complex loads target DNA and prepares it for cutting by the Cas3 enzyme. These structures reveal a process with multiple layers of error detection — a molecular redundancy that prevents unintended genomic damage, the researchers say.

CRISPR-Cas3 is a subtype of the CRISPR-Cas system, a widely adopted molecular tool for precision gene editing in biomedical research. Aspects of its mechanism of action, however, particularly how it searches for its DNA targets, were unclear and concerns about unintended off-target effects have raised questions about the safety of CRISPR-Cas for treating human diseases.

High-resolution details of these structures shed light on ways to ensure accuracy and avert off-target effects when using CRISPR for gene editing.

“To solve problems of specificity, we need to understand every step of CRISPR complex formation,” said Maofu Liao, assistant professor of cell biology at Harvard Medical School and co-senior author of the study. “Our study now shows the precise mechanism for how invading DNA is captured by CRISPR, from initial recognition of target DNA and through a process of conformational changes that make DNA accessible for final cleavage by Cas3.”

Target search

Discovered less than a decade ago, CRISPR-Cas is an adaptive defense mechanism that bacteria use to fend off viral invaders. This process involves bacteria capturing snippets of viral DNA, which are then integrated into its genome and which produce short RNA sequences known as crRNA (CRISPR RNA). These crRNA snippets are used to spot “enemy” presence.

Acting like a barcode, crRNA is loaded onto members of the CRISPR family of enzymes, which perform the function of sentries that roam the bacteria and monitor for foreign code. If these riboprotein complexes encounter genetic material that matches its crRNA, they chop up that DNA to render it harmless. CRISPR-Cas subtypes, notably Cas9, can be programmed with synthetic RNA in order to cut genomes at precise locations, allowing researchers to edit genes with unprecedented ease.

To better understand how CRISPR-Cas functions, Liao partnered with Ailong Ke of Cornell University. Their teams focused on type 1 CRISPR, the most common subtype in bacteria, which utilizes a riboprotein complex known as CRISPR Cascade for DNA capture and the enzyme Cas3 for cutting foreign DNA.

Through a combination of biochemical techniques and cryo-electron microscopy, they reconstituted stable Cascade in different functional states, and further generated snapshots of Cascade as it captured and processed DNA at a resolution of up to 3.3 angstroms — or roughly three times the diameter of a carbon atom.

Seeing is believing

In CRISPR-Cas3, crRNA is loaded onto CRISPR Cascade, which searches for a very short DNA sequence known as PAM that indicates the presence of foreign viral DNA.

Liao, Ke and their colleagues discovered that as Cascade detects PAM, it bends DNA at a sharp angle, forcing a small portion of the DNA to unwind. This allows an 11-nucleotide stretch of crRNA to bind with one strand of target DNA, forming a “seed bubble.”

The seed bubble acts as a fail-safe mechanism to check whether the target DNA matches the crRNA. If they match correctly, the bubble is enlarged and the remainder of the crRNA binds with its corresponding target DNA, forming what is known as an “R-loop” structure.

Once the R-loop is completely formed, the CRISPR Cascade complex undergoes a conformational change that locks the DNA into place. It also creates a bulge in the second, non-target strand of DNA, which is run through a separate location on the Cascade complex.

Only when a full R-loop state is formed does the Cas3 enzyme bind and cut the DNA at the bulge created in the non-target DNA strand.

The findings reveal an elaborate redundancy to ensure precision and avoid mistakenly chopping up the bacteria’s own DNA.

“To apply CRISPR in human medicine, we must be sure the system is accurate and that it does not target the wrong genes,” said Ke, who is co-senior author of the study. “Our argument is that the CRISPR-Cas3 subtype has evolved to be a precise system that carries the potential to be a more accurate system to use for gene editing. If there is mis-targeting, we know how to manipulate the system because we know the steps involved and where we might need to intervene.”

Setting the sights

Structures of CRISPR Cascade without target DNA and in its post-R-loop conformational states have been described, but this study is the first to reveal the full sequence of events from seed bubble formation to R-loop formation at high resolution.

In contrast to the scalpel-like Cas9, CRISPR-Cas3 acts like a shredder that chews DNA up beyond repair. While CRISPR-Cas3 has, thus far, limited utility for precision gene editing, it is being developed as a tool to combat antibiotic-resistant strains of bacteria. A better understanding of its mechanisms may broaden the range of potential applications for CRISPR-Cas3.

In addition, all CRISPR-Cas subtypes utilize some version of an R-loop formation to detect and prepare target DNA for cleavage. The improved structural understanding of this process can now enable researchers to work toward modifying multiple types of CRISPR-Cas systems to improve their accuracy and reduce the chance of off-target effects in biomedical applications.

“Scientists hypothesized that these states existed but they were lacking the visual proof of their existence,” said co-first author Min Luo, postdoctoral fellow in the Liao lab at HMS. “The main obstacles came from stable biochemical reconstitution of these states and high-resolution structural visualization. Now, seeing really is believing.”

“We’ve found that these steps must occur in a precise order,” Luo said. “Evolutionarily, this mechanism is very stringent and has triple redundancy, to ensure that this complex degrades only invading DNA.”

Trial counters current thinking about treatment effectiveness — ScienceDaily

Methicillin-resistant Staphylococcus aureus (MRSA) bacteria are resistant to multiple antibiotics and commonly cause skin infections that can lead to more serious or life-threatening infection in other parts of the body. In new findings published in The New England Journal of Medicine, researchers found that two common, inexpensive antimicrobials can help patients heal from MRSA skin abscesses. The findings suggest that current treatment options for MRSA still have a role, even as scientists continue to search for new antimicrobial products. The research was funded by the National Institute of Allergy and Infectious Diseases (NIAID), a part of the National Institutes of Health (NIH).

The study was conducted at hospitals across the United States and involved 796 children and adults with small, uncomplicated skin abscesses. All patients had their abscesses opened and drained as part of standard MRSA treatment. The patients were then sorted into three groups, each of which received a different, ten-day oral treatment regimen. One group received clindamycin, a second group received trimethoprim-sulfamethoxazole (TMP-SMX), and the third group received placebo.

The group treated with clindamycin had an 81.7 percent cure rate, and the group that received TMP-SMX had an 84.6 percent cure rate. The placebo group had a 62.9 percent cure rate. According to the researchers, the findings contradict a commonly held belief that antimicrobial treatment is little better than doing nothing for MRSA skin infections. It corroborates the findings of another NIAID-funded study demonstrating that TMP-SMX treatment resulted in better clinical outcomes than placebo for MRSA skin abscesses, and also upholds other findings that both clindamycin and TMP-SMX are equally beneficial in treating MRSA skin infections.

The researchers note, however, that the side effects of clindamycin and TMP-SMX (including nausea, diarrhea, and possible new Clostridium difficile infections) can be severe. In addition, some strains of Staphylococcus are resistant to clindamycin. The authors recommend that healthcare providers weigh the risks but not dismiss these antimicrobials out of hand as viable treatment options for MRSA skin abscesses.

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