Rumen cellulosomics : divergent fiber-degrading strategies revealed by comparative genome-wide analysis of six ruminococcal strains

Peer reviewedPublisher PD

Complexity of the Ruminococcus flavefaciens FD-1 cellulosome reflects an expansion of family-related protein-protein interactions

This work was supported in part by the European Union, Area NMP.2013.1.1–2: Self-assembly of naturally occurring nanosystems: CellulosomePlus Project number: 604530, and by the EU Seventh Framework Programme (FP7 2007–2013) under the WallTraC project (Grant Agreement no 263916), and BioStruct-X (grant agreement no 283570). This paper reflects the author’s views only. The European Community is not liable for any use that may be made of the information contained herein. CMGAF is also supported by Fundação para a Ciência e a Tecnologia (Lisbon, Portugal) through grants PTDC/BIA-PRO/103980/2008 and EXPL/BIA-MIC/1176/2012. EAB is also funded by a grant (No. 1349/13) from the Israel Science Foundation (ISF), Jerusalem, Israel and by a grant (No. 2013284) from the U.S.-Israel Binational Science Foundation (BSF). E.A.B. is the incumbent of The Maynard I. and Elaine Wishner Chair of Bio-organic Chemistry.Peer reviewedPublisher PD

Applicability of a short/rapid 13C-urea breath test for Helicobacter pylori: retrospective multicenter chart review study

<p>Abstract</p> <p>Background</p> <p>Carbon labeled urea breath tests usually entail a two point sampling with a 20 to 30-minute gap. Our aim was to evaluate the duration of time needed for diagnosing <it>Helicobacter pylori </it>by the BreathID^®System.</p> <p>Methods</p> <p>This is a retrospective multicenter chart review study. Test location, date, delta over baseline, and duration of the entire test were recorded. Consecutively ¹³C urea breath tests results were extracted from the files over a nine year period.</p> <p>Results</p> <p>Of the 12,791 tests results, 35.1% were positively diagnosed and only 0.1% were inconclusive. A statistically significant difference in prevalence among the countries was found: Germany showing the lowest, 13.3%, and Israel the highest, 44.1%. Significant differences were found in time to diagnosis: a positive diagnosis had the shortest and an inconclusive result had the longest. Overall test duration averaged 15.1 minutes in Germany versus approximately 13 minutes in other countries. Diagnosis was achieved after approximately 9 minutes in Israel, Italy and Switzerland, but after 10 on average in the others. The mean delta over baseline value for a negative diagnosis was 1.03 ± 0.86, (range, 0.9 - 5), versus 20.2 ± 18.9, (range, 5.1 - 159.4) for a positive one.</p> <p>Conclusions</p> <p>The BreathID^®System used in diagnosing <it>Helicobacter pylori </it>can safely shorten test duration on average of 10-13 minutes without any loss of sensitivity or specificity and with no test lasting more than 21 minutes.</p

Automated stage discrimination of Parkinson’s disease

International audienceTreament plans for Parkinson’s disease are based on a disease stage scale, which is generally determined using a manual, observational procedure. Automated, sensor based discrimination saves labour and cost in clinical settings and may offer augmented stage determination accuracy. Previous automated devices were either cumbersome or costly and were not suitable for individuals who cannot walk without support.Since 2017, a device has been available that successfully detects Parkinson’s disease and operates for people who cannot walk without support. In the present study, the suitability of this device for automated discrimination of Parkinson’s disease stages is tested. The device consists of a walking frame fitted with sensors to simultaneously support walking and monitor patient gait. Sixty-five Parkinson’s disease patients in HYstages 1 to 4 and twenty-four heathy controls were subjected to supported timed up and go (TUG) tests, while using the walking frame. The walking trajectory, velocity, acceleration and force were recorded by the device throughout the tests. These physical parameters were converted into symptomic spatio-temporal quanitities that are conventionaly used in Parksinon’s disease gait assessment. An ANOVA Test extended by a confidence interval analysis indicated statistically significant seperability between HYstages for the following spatio-temporal quantities: TUG time (p<0.001), straight like walking time (p<0.001), turning time (p<0.001) and step count (p<0.001). A negative correlation was obtained for mean step velocity (p<0.001) and mean step length (p<0.001). Moreover, correlations were established between these, as well as additional spatio-temporal quanitities, and disease duration, levodopa dose, motor fluctuation, dyskinesia and the mobile part of the unified Parkinson’s disease rating scale. We have proven that stage discrimination of Parkinson’s disease can be automated, even to patients who cannot support themselves. A similar method might be successfully applied to other gait disorders

The Impact of COVID-19 Pandemic on Management and Outcome in Patients with Heart Failure

Background: The COVID-19 pandemic has adversely affected the provision of health care and disease management around the world. COVID-19 carries a high morbidity and mortality rate in elderly and people with comorbidities, including heart failure (HF). The present study addressed the clinical management and outcomes of HF patients during the pandemic. Methods: We evaluated the clinical management and survival rate of HF patients during the COVID-19 pandemic in Israel (March 2020–April 2021). Results: The cohort included 6748 patients with a diagnosis of HF during the study period. During this period, 843 HF patients (12.5%) were infected with COVID-19, and 194 died from COVID-19, a 23% mortality rate. Patients infected with COVID-19 had a higher percentage of diabetes and obesity. Predictors of mortality included age, male sex, reduced functional capacity, renal dysfunction, and absence of renin–angiotensin system inhibition. During the pandemic, there was a marked decrease in the usage of medical services in the cohort. Cardiovascular hospitalizations, all hospitalization, and emergency room visits were significantly decreased compared to the two years prior to the pandemic, particularly during the lockdowns. There was also an initial decrease in HF clinic visits. Mortality rates were very similar during the pandemic compared to previous years. There was a decline in non-COVID-19 deaths, which were replaced with deaths due to COVID-19. This may result from competing effects and reduced exposure to respiratory infections and other insults due to social distancing. Conclusions: Mortality rates in HF patients infected with COVID-19 were high. The COVID-19 pandemic resulted in the reduced usage of health services but without increased overall mortality

Elaborate cellulosome architecture of Acetivibrio cellulolyticus revealed by selective screening of cohesin–dockerin interactions

Cellulosic waste represents a significant and underutilized carbon source for the biofuel industry. Owing to the recalcitrance of crystalline cellulose to enzymatic degradation, it is necessary to design economical methods of liberating the fermentable sugars required for bioethanol production. One route towards unlocking the potential of cellulosic waste lies in a highly complex class of molecular machines, the cellulosomes. Secreted mainly by anaerobic bacteria, cellulosomes are structurally diverse, cell surface-bound protein assemblies that can contain dozens of catalytic components. The key feature of the cellulosome is its modularity, facilitated by the ultra-high affinity cohesin–dockerin interaction. Due to the enormous number of cohesin and dockerin modules found in a typical cellulolytic organism, a major bottleneck in understanding the biology of cellulosomics is the purification of each cohesin- and dockerin-containing component, prior to analyses of their interaction. As opposed to previous approaches, the present study utilized proteins contained in unpurified whole-cell extracts. This strategy was made possible due to an experimental design that allowed for the relevant proteins to be “purified” via targeted affinity interactions as a function of the binding assay. The approach thus represents a new strategy, appropriate for future medium- to high-throughput screening of whole genomes, to determine the interactions between cohesins and dockerins. We have selected the cellulosome of Acetivibrio cellulolyticus for this work due to its exceptionally complex cellulosome systems and intriguing diversity of its cellulosomal modular components. Containing 41 cohesins and 143 dockerins, A. cellulolyticus has one of the largest number of potential cohesin–dockerin interactions of any organism, and contains unusual and novel cellulosomal features. We have surveyed a representative library of cohesin and dockerin modules spanning the cellulosome’s total cohesin and dockerin sequence diversity, emphasizing the testing of unusual and previously-unknown protein modules. The screen revealed several novel cell-bound cellulosome architectures, thus expanding on those previously known, as well as soluble cellulose systems that are not bound to the bacterial cell surface. This study sets the stage for screening the entire complement of cellulosomal components from A. cellulolyticus and other organisms with large cellulosome systems. The knowledge gained by such efforts brings us closer to understanding the exceptional catalytic abilities of cellulosomes and will allow the use of novel cellulosomal components in artificial assemblies and in enzyme cocktails for sustainable energy-related research programs