Bioinformatic Analysis of Sulfotransferases from an Unexplored Gut Microbe, Sutterella wadsworthensis 3_1_45B: Possible Roles towards Detoxification via Sulfonation by Members of the Human Gut Microbiome.

Sulfonation, primarily facilitated by sulfotransferases, plays a crucial role in the detoxification pathways of endogenous substances and xenobiotics, promoting metabolism and elimination. Traditionally, this bioconversion has been attributed to a family of human cytosolic sulfotransferases (hSULTs) known for their high sequence similarity and dependence on 3'-phosphoadenosine 5'-phosphosulfate (PAPS) as a sulfo donor. However, recent studies have revealed the presence of PAPS-dependent sulfotransferases within gut commensals, indicating that the gut microbiome may harbor a diverse array of sulfotransferase enzymes and contribute to detoxification processes via sulfation. In this study, we investigated the prevalence of sulfotransferases in members of the human gut microbiome. Interestingly, we stumbled upon PAPS-independent sulfotransferases, known as aryl-sulfate sulfotransferases (ASSTs). Our bioinformatics analyses revealed that members of the gut microbial genus Sutterella harbor multiple asst genes, possibly encoding multiple ASST enzymes within its members. Fluctuations in the microbes of the genus Sutterella have been associated with various health conditions. For this reason, we characterized 17 different ASSTs from Sutterella wadsworthensis 3_1_45B. Our findings reveal that SwASSTs share similarities with E. coli ASST but also exhibit significant structural variations and sequence diversity. These differences might drive potential functional diversification and likely reflect an evolutionary divergence from their PAPS-dependent counterparts.

Use of bivalirudin for anticoagulation in pediatric extracorporeal membrane oxygenation (ECMO).

This study describes the use of bivalirudin in children on extracorporeal membrane oxygenation (ECMO). Pediatric patients receiving bivalirudin were compared to patients receiving heparin as the anticoagulant on ECMO. Data was collected for children under 18 years of age supported by ECMO from January 2016 to December 2019. Data collected included demographics, diagnosis, ECMO indication, type, and duration, indication for bivalirudin use, dose range, activated partial thromboplastin time (aPTT) levels, minor and major bleeding, hemolysis, and mortality. Forty pediatric patients received ECMO; eight received bivalirudin primarily for anticoagulation. The median age was 4 months (IQR 0.5, 92) in the heparin cohort, 0.6 months (IQR 0.0, 80.0) in the primary bivalirudin cohort. The indication for ECMO was respiratory in 5 patients (18%) in the heparin group versus 6 (75%) in the primary bivalirudin group, cardiac in 18 (67%) in heparin versus 1 (12.5%) in primary bivalirudin, and extracorporeal-cardiopulmonary resuscitation (E-CPR) in 4 (15%) in heparin versus 1 (12.5%) in primary bivalirudin. Bivalirudin was the initial anticoagulant for eight patients (66.6%) while three (25%) were switched due to concern for heparin-induced thrombocytopenia (HIT) and one (8%) for heparin resistance. The median time to achieve therapeutic aPTT was 14.5 hours compared to 12 hours in the heparin group. Sixty-five percent of aPTT values in the bivalirudin and 44% of values in the heparin group were in the therapeutic range in the first 7 days. Patients with primary bivalirudin use had significantly lower dose requirement at 12 (p = 0.003), 36 (p = 0.007), and 48 (p = 0.0002) hours compared to patients with secondary use of bivalirudin. One patient (12.5%) had major bleeding, and two patients (25%) required circuit change in the primary bivalirudin cohort. Bivalirudin may provide stable and successful anticoagulation in children. Further large, multicenter studies are needed to confirm these findings.

Symptoms of Depression, Anxiety, Post-Traumatic Stress Disorder, and Suicidal Ideation Among State, Tribal, Local, and Territorial Public Health Workers During the COVID-19 Pandemic - United States, March-April 2021.

Increases in mental health conditions have been documented among the general population and health care workers since the start of the COVID-19 pandemic (1-3). Public health workers might be at similar risk for negative mental health consequences because of the prolonged demand for responding to the pandemic and for implementing an unprecedented vaccination campaign. The extent of mental health conditions among public health workers during the COVID-19 pandemic, however, is uncertain. A 2014 survey estimated that there were nearly 250,000 state and local public health workers in the United States (4). To evaluate mental health conditions among these workers, a nonprobability-based online survey was conducted during March 29-April 16, 2021, to assess symptoms of depression, anxiety, post-traumatic stress disorder (PTSD), and suicidal ideation among public health workers in state, tribal, local, and territorial public health departments. Among 26,174 respondents, 52.8% reported symptoms of at least one mental health condition in the preceding 2 weeks, including depression (30.8%), anxiety (30.3%), PTSD (36.8%), or suicidal ideation (8.4%). The highest prevalence of symptoms of a mental health condition was among respondents aged ≤29 years (range = 13.6%-47.4%) and transgender or nonbinary persons (i.e., those who identified as neither male nor female) of all ages (range = 30.4%-65.5%). Public health workers who reported being unable to take time off from work were more likely to report adverse mental health symptoms. Severity of symptoms increased with increasing weekly work hours and percentage of work time dedicated to COVID-19 response activities. Implementing prevention and control practices that eliminate, reduce, and manage factors that cause or contribute to public health workers' poor mental health might improve mental health outcomes during emergencies.

Symptoms of Depression, Anxiety, Post-Traumatic Stress Disorder, and Suicidal Ideation Among State, Tribal, Local, and Territorial Public Health Workers During the COVID-19 Pandemic - United States, March-April 2021.

Increases in mental health conditions have been documented among the general population and health care workers since the start of the COVID-19 pandemic (1-3). Public health workers might be at similar risk for negative mental health consequences because of the prolonged demand for responding to the pandemic and for implementing an unprecedented vaccination campaign. The extent of mental health conditions among public health workers during the COVID-19 pandemic, however, is uncertain. A 2014 survey estimated that there were nearly 250,000 state and local public health workers in the United States (4). To evaluate mental health conditions among these workers, a nonprobability-based online survey was conducted during March 29-April 16, 2021, to assess symptoms of depression, anxiety, post-traumatic stress disorder (PTSD), and suicidal ideation among public health workers in state, tribal, local, and territorial public health departments. Among 26,174 respondents, 53.0% reported symptoms of at least one mental health condition in the preceding 2 weeks, including depression (32.0%), anxiety (30.3%), PTSD (36.8%), or suicidal ideation (8.4%). The highest prevalence of symptoms of a mental health condition was among respondents aged ≤29 years (range = 13.6%-47.4%) and transgender or nonbinary persons (i.e., those who identified as neither male nor female) of all ages (range = 30.4%-65.5%). Public health workers who reported being unable to take time off from work were more likely to report adverse mental health symptoms. Severity of symptoms increased with increasing weekly work hours and percentage of work time dedicated to COVID-19 response activities. Implementing prevention and control practices that eliminate, reduce, and manage factors that cause or contribute to public health workers' poor mental health might improve mental health outcomes during emergencies.

Histatin-1 Attenuates LPS-Induced Inflammatory Signaling in RAW264.7 Macrophages.

Macrophages play a critical role in the inflammatory response to environmental triggers, such as lipopolysaccharide (LPS). Inflammatory signaling through macrophages and the innate immune system are increasingly recognized as important contributors to multiple acute and chronic disease processes. Nitric oxide (NO) is a free radical that plays an important role in immune and inflammatory responses as an important intercellular messenger. In addition, NO has an important role in inflammatory responses in mucosal environments such as the ocular surface. Histatin peptides are well-established antimicrobial and wound healing agents. These peptides are important in multiple biological systems, playing roles in responses to the environment and immunomodulation. Given the importance of macrophages in responses to environmental triggers and pathogens, we investigated the effect of histatin-1 (Hst1) on LPS-induced inflammatory responses and the underlying molecular mechanisms in RAW264.7 (RAW) macrophages. LPS-induced inflammatory signaling, NO production and cytokine production in macrophages were tested in response to treatment with Hst1. Hst1 application significantly reduced LPS-induced NO production, inflammatory cytokine production, and inflammatory signaling through the JNK and NF-kB pathways in RAW cells. These results demonstrate that Hst1 can inhibit LPS-induced inflammatory mediator production and MAPK signaling pathways in macrophages.

Evolution of drug resistance in HIV protease.

BACKGROUND: Drug resistance is a critical problem limiting effective antiviral therapy for HIV/AIDS. Computational techniques for predicting drug resistance profiles from genomic data can accelerate the appropriate choice of therapy. These techniques can also be used to identify protease mutants for experimental studies of resistance and thereby assist in the development of next-generation therapies. Few studies, however, have assessed the evolution of resistance from genotype-phenotype data. RESULTS: The machine learning produced highly accurate and robust classification of resistance to HIV protease inhibitors. Genotype data were mapped to the enzyme structure and encoded using Delaunay triangulation. Estimates of evolutionary relationships, based on this encoding, and using Minimum Spanning Trees, showed clusters of mutations that closely resemble the wild type. These clusters appear to evolve uniquely to more resistant phenotypes. CONCLUSIONS: Using the triangulation metric and spanning trees results in paths that are consistent with evolutionary theory. The majority of the paths show bifurcation, namely they switch once from non-resistant to resistant or from resistant to non-resistant. Paths that lose resistance almost uniformly have far lower levels of resistance than those which either gain resistance or are stable. This strongly suggests that selection for stability in the face of a rapid rate of mutation is as important as selection for resistance in retroviral systems.

Comparison of a predefined dose increment nomogram with a percentage adjustment nomogram in patients receiving argatroban therapy.

OBJECTIVE: To determine the compliance with a predefined dose increment (PDI) nomogram compared with a percentage adjustment (PA) nomogram for the dose titration of argatroban therapy. DESIGN: This was a single-center, retrospective chart review. SETTING AND PARTICIPANTS: This study was conducted in a tertiary care teaching hospital. Patients were included if they received argatroban from 2013 to 2016. OUTCOME MEASURES: The primary safety outcome was the percentage of appropriate dose titrations. The secondary safety and efficacy outcomes included the median time to therapeutic activated partial thromboplastin time (aPTT), the median argatroban dose once therapeutic, and the median time in the therapeutic, subtherapeutic, and supratherapeutic aPTT ranges, as well as the bleeding and thrombotic events during hospitalization. RESULTS: Seventy-seven patients were included in the study. There was no statistically significant difference in the percentage of titrations performed appropriately (P = 0.17). The median time to goal aPTT, the dose when first therapeutic, and the time aPTT was subtherapeutic were similar in both the arms. The patients in the PDI arm were on argatroban for a median time of 55 hours compared with 110.5 hours for the patients in the PA arm (P = 0.001). The patients in the PA arm spent more time in the therapeutic range (P < 0.05) and less time in the supratherapeutic range (P < 0.005). CONCLUSION: Although there was no difference in the percentage of appropriate dose titrations, the patients in the PA arm spent more time on argatroban, had greater time in the therapeutic aPTT range, and had less time in the supratherapeutic aPTT range. Future studies that include a larger sample size, matching therapeutic aPTT ranges, and similar initial infusion rates would help evaluate further the outcomes between the PDI and PA nomograms.

The missing pieces in the jigsaw and need for cohesive research amidst coronavirus infectious disease 2019 global response.

Identifying the research needs and gaps amidst this COVID-19 travelling across the countries is absolutely important for finely improving on the way we think and act. The natural history of the disease as well as viral shedding in different stages of clinical illness needs to be known which helps in triaging the patients in hospital settings. Animal and environmental interface need to be studied for defining the high-risk situations. Transmission dynamics in community or hospital and defining the laboratory criteria for the case confirmation will be most crucial. Gene sequencing and validation and, suitable use of molecular based tests such as real-time polymerase chain reaction (qRT-PCR) should be clearly evaluated for diagnosis and/ or surveillance. The movement control strategy must be defined to prevent secondary transmission in healthcare as well as in community settings. Repurposing of drug molecules is an elegant strategy to develop therapeutics in the case of pandemics quickly. Unproven practices and treatment protocols should invite critical scrutiny on the basis of ethics. Socioeconomic status of the community is also an important determinant for the compliance and sustainable public health measures.

Outcomes associated with Clostridium difficile infection in patients with chronic liver disease.

Patients with chronic liver disease (CLD) have frequent exposure to Clostridium difficile infection (CDI) risk factors but the incidence and aetiology of CDI on this population is poorly understood. The aim of this study was to assess the incidence, disease presentation and outcomes of CDI in patients with underlying CLD. The Health Care and Utilization Project National Inpatient Sample (HCUP-NIS) 2009 dataset was used to identify patients with CLD who developed CDI along with matched non-CLD patients with CDI. Using the NIS dataset, the incidence rate of CDI was 189.4/10 000 discharges in CLD patients vs. 83.7/10 000 discharges in the non-CLD matched cohort (P < 0.001). Compared with non-CLD, comorbidity-matched controls with CDI, CLD patients with CDI had higher likelihood of in-hospital mortality (8.8% vs. 18.6%, P < 0.001), increased length of stay by 1.19 days (P < 0.001) and increased total costs by $8632 (P < 0.001). In separate analyses using a tertiary case database of hospitalised patients in Houston, Texas (2006-2016) with CLD and CDI (n = 41) compared with patients with CDI but not CLD (n = 111), CLD patients had significantly higher Charlson comorbidity index (P < 0.0001) but similar risk factors for CDI and CDI-related disease presentation compared with non-CLD patients. In conclusion, CDI-related risk factors were almost universally present in the CLD population. CDI resulted in worse outcomes in this population.

Pharmacist Outpatient Prescription Review in the Emergency Department: A Pediatric Tertiary Hospital Experience.

OBJECTIVES: This study aimed to assess the frequency, type, and potential severity of errors intercepted by pharmacists on review of discharge prescriptions in a pediatric emergency department (ED). METHODS: This was a retrospective, observational study conducted in the ED of a pediatric teaching hospital. A daily report of prescriptions from the previous day was reviewed by a pharmacist for safety and efficacy. If an intervention was deemed necessary, the prescriber was contacted for clarification. In situations where patient harm could occur, the physician performing follow-ups was contacted by phone. The interventions were categorized based on type and potential severity. Physician response rates and intervention acceptance rates were assessed. RESULTS: Approximately 23,600 prescriptions were reviewed during a 1-year period with 60 interventions (0.25% intervention rate). Of the 60 interventions, 3% were estimated to have no severity, 80% were estimated to have minor, 12% moderate, and 5% major potential severity. The most common types of interventions were optimization of therapy, drug overdose, or dose omission at 33%, 32%, and 14%, respectively. Eighty-five percent of physicians responded; 73% accepted the intervention whereas 27% provided a rationale for their decision. More importantly, valuable information was gained, allowing for implementation of system fixes to prevent future errors. On an average, pharmacists spent 45 minutes reviewing and clarifying prescriptions each day. CONCLUSIONS: Pharmacists in the ED can provide a valuable service by reviewing discharge prescriptions. A small amount of time dedicated to this service can lead to detection of clinically significant preventable medication errors and optimization of prescription therapy.

Stereospecific Formation of E- and Z-Disubstituted Double Bonds by Dehydratase Domains from Modules 1 and 2 of the Fostriecin Polyketide Synthase.

The dehydratase domain FosDH1 from module 1 of the fostriecin polyketide synthase (PKS) catalyzed the stereospecific interconversion of (3R)-3-hydroxybutyryl-FosACP1 (5) and (E)-2-butenoyl-FosACP1 (11), as established by a combination of direct LC-MS/MS and chiral GC-MS. FosDH1 did not act on either (3S)-3-hydroxybutyryl-FosACP1 (6) or (Z)-2-butenoyl-FosACP1 (12). FosKR2, the ketoreductase from module 2 of the fostriecin PKS that normally provides the natural substrate for FosDH2, was shown to catalyze the NADPH-dependent stereospecific reduction of 3-ketobutyryl-FosACP2 (23) to (3S)-3-hydroxybutyryl-FosACP2 (8). Consistent with this finding, FosDH2 catalyzed the interconversion of the corresponding triketide substrates (3R,4E)-3-hydroxy-4-hexenoyl-FosACP2 (18) and (2Z,4E)-2,4-hexadienoyl-FosACP2 (21). FosDH2 also catalyzed the stereospecific hydration of (Z)-2-butenoyl-FosACP2 (14) to (3S)-3-hydroxybutyryl-FosACP2 (8). Although incubation of FosDH2 with (3S)-3-hydroxybutyryl-FosACP2 (8) did not result in detectable accumulation of (Z)-2-butenoyl-FosACP2 (14), FosDH2 catalyzed the slow exchange of the 3-hydroxy group of 8 with [18O]-water. FosDH2 unexpectedly could also support the stereospecific interconversion of (3R)-3-hydroxybutyryl-FosACP2 (7) and (E)-2-butenoyl-FosACP2 (13).

Development and Validation of a Clostridium difficile Health-related Quality-of-Life Questionnaire.

GOALS AND BACKGROUND: Patients with Clostridium difficile infection (CDI) can experience long-term symptoms and poor quality of life due to the disease. Despite this, a health-related quality of life (HRQOL) instrument specific for patients with CDI does not exist. The aim of this study was to develop and validate a disease-specific instrument to assess HRQOL in patients with CDI. STUDY: A systematic literature review was conducted to identify HRQOL instruments and questions related to general health (n=3) or gastrointestinal disease (n=12) potentially related to CDI HRQOL. Removing duplicate questions and using direct patient or clinician interviews, a 36-item survey was developed. The survey was then tested using 98 patients with CDI and compared with the RAND Short-Form 36 (SF-36) Health Survey. Psychometric analysis techniques were used to identify domains and remove redundant items. RESULTS: Exploratory factor analysis identified 3 major domains (physical, mental, and social) with 4 associated subdomains. Survey overall and domain scores displayed good internal consistency (Cronbach α coefficient >0.87) and concurrent validity evidenced by significant correlation with SF-36 scores. The C. difficile survey scores were better able than the SF-36 to discriminate quality-of-life score differences in patients with primary versus recurrent CDI and increasing time since last episode of CDI. The final version contained 32 items related to the physical, mental, and social health of CDI patients. CONCLUSION: The properties of the newly developed Cdiff32 should make it appropriate to assess changes over time in HRQOL in patients with CDI.

Clinical practice patterns in hospitalized patients at risk for invasive candidiasis: role of antifungal stewardship programs in an era of rapid diagnostics.

BACKGROUND: Rapid diagnostic tests for Candida are becoming available that may supplement traditional microbiological identification. OBJECTIVE: Assess clinical practice patterns in patients with or at risk of candidiasis who may benefit from the use of rapid diagnostic tests. METHODS: This was a prospective cohort study of patients with candidemia or receiving systemic antifungals conducted at a university-affiliated tertiary care hospital. Time to initiation of therapy, Candida species, time to identification, and indications for antifungal use were assessed. RESULTS: A total of 162 patients with candidemia aged 58 ± 17 years were identified. Average time to yeast identification yeast was 2.2 ± 1.3 days and varied by Candida species (range = 0.6-7.9 days). Average time for patient to start antifungal therapy was 3.5 ± 2.1 days. In Monte Carlo simulations, average time to initiation of antifungal therapy was 0.6 ± 0.2 days for T2Candida, 2.6 ± 1.3 days for PNA-FISH (fluorescence in situ hybridization using peptide nucleic acid probes), and 2.5 ± 1.4 days for MALDI-TOF (matrix-assisted laser desorption/ionization time of flight). Use of T2Candida on the day of the blood culture collection resulted in 3136 to 6078 fewer doses of echinocandins annually per 5000 patients. CONCLUSION: Many interventions are possible for antifungal stewardship programs to improve care of patients at risk for systemic candidiasis, including rapid identification of yeast species and limiting unnecessary antifungal agents. Technology enabling rapid diagnosis of Candida will be paramount to appropriate, cost-effective treatment of patients with or at risk for candidiasis.

Ecological, beneficial, and pathogenic functions of the Type 9 Secretion System.

The recently discovered Type 9 Secretion System (T9SS) is present in bacteria of the Fibrobacteres-Bacteroidetes-Chlorobi superphylum, which are key constituents of diverse microbiomes. T9SS is instrumental in the extracellular secretion of over 270,000 proteins, including peptidases, sugar hydrolases, metal ion-binding proteins, and metalloenzymes. These proteins are essential for the interaction of bacteria with their environment. This mini-review explores the extensive array of proteins secreted by the T9SS. It highlights the diverse functions of these proteins, emphasizing their roles in pathogenesis, bacterial interactions, host colonization, and the overall health of the ecosystems inhabited by T9SS-containing bacteria.

Synthesis of versatile neuromodulatory molecules by a gut microbial glutamate decarboxylase.

Dysbiosis of the microbiome correlates with many neurological disorders, yet very little is known about the chemistry that controls the production of neuromodulatory molecules by gut microbes. Here, we found that an enzyme glutamate decarboxylase (BfGAD) of a gut microbe Bacteroides fragilis forms multiple neuromodulatory molecules such as γ-aminobutyric acid (GABA), hypotaurine, taurine, homotaurine, and ß-alanine. We evolved BfGAD and doubled its taurine productivity. Additionally, we increased its specificity towards the substrate L-glutamate. Here, we provide a chemical strategy via which the BfGAD activity could be fine-tuned. In future, this strategy could be used to modulate the production of neuromodulatory molecules by gut microbes.

Spatial organization of a soil cyanobacterium and its cyanosphere through GABA/Glu signaling to optimize mutualistic nitrogen fixation.

Soil biocrusts are characterized by the spatial self-organization of resident microbial populations at small scales. The cyanobacterium Microcoleus vaginatus, a prominent primary producer and pioneer biocrust former, relies on a mutualistic carbon (C) for nitrogen (N) exchange with its heterotrophic cyanosphere microbiome, a mutualism that may be optimized through the ability of the cyanobacterium to aggregate into bundles of trichomes. Testing both environmental populations and representative isolates, we show that the proximity of mutualistic diazotroph populations results in M. vaginatus bundle formation orchestrated through chemophobic and chemokinetic responses to gamma-aminobutyric acid (GABA) /glutamate (Glu) signals. The signaling system is characterized by: a high GABA sensitivity (nM range) and low Glu sensitivity (µM to mM), the fact that GABA and Glu are produced by the cyanobacterium as an autoinduction response to N deficiency, and by the presence of interspecific signaling by heterotrophs in response to C limitation. Further, it crucially switches from a positive to a negative feedback loop with increasing GABA concentration, thus setting maximal bundle sizes. The unprecedented use of GABA/Glu as an intra- and interspecific signal in the spatial organization of microbiomes highlights the pair as truly universal infochemicals.

A randomized, double-blind, placebo-controlled, crossover study of respiratory safety of lemborexant in moderate to severe obstructive sleep apnea.

STUDY OBJECTIVES: To evaluate the respiratory safety of lemborexant among adults and older adults with moderate to severe obstructive sleep apnea (OSA). METHODS: E2006-A001-113 (Study 113; NCT04647383) was a double-blind, two-period crossover, placebo-controlled study in adults (ages ≥ 45 to ≤ 90 years, n = 33) with moderate (apnea-hypopnea index [AHI] score ≥ 15 to < 30 events/h, n = 13) or severe (AHI ≥ 30 events/h, n = 20) OSA. Participants were randomized to lemborexant 10 mg (LEM10) or placebo (PBO) for two treatment periods of 8 nights with a ≥ 14-day washout period. AHI and peripheral oxygen saturation were evaluated after treatment on Day 1 (after a single dose) and Day 8 (after multiple doses). RESULTS: No significant differences in AHI were observed after single and multiple doses of LEM10 compared with PBO in participants with moderate to severe OSA (least-squares mean: single-dose LEM10, 41.7; PBO, 44.8; multiple-dose LEM10, 44.9; PBO, 45.7). In addition, there were no significant differences between treatments in peripheral oxygen saturation (least-squares mean: single-dose LEM10, 93.0; PBO, 93.1; multiple-dose LEM10, 93.1; PBO, 93.4). Further, there were no significant differences between treatments in percentage of total sleep time with peripheral oxygen saturation < 90%, < 85%, or < 80%. No significant differences were observed between treatments when AHI and peripheral oxygen saturation outcomes were analyzed by OSA severity. Altogether, 6/33 (18.2%) participants receiving LEM10, vs 3/33 (9.1%) PBO, reported treatment-emergent adverse events, mostly mild in severity. CONCLUSIONS: LEM10 demonstrated respiratory safety and was well tolerated with single-dose and multiple-dose administration in participants with moderate to severe OSA. This suggests that LEM may be a treatment option for patients with OSA and comorbid insomnia. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: A Study to Evaluate the Respiratory Safety of Lemborexant in Adult and Elderly Participants With Moderate to Severe Obstructive Sleep Apnea and in Adult and Elderly Participants With Moderate to Severe Chronic Obstructive Pulmonary Disease; URL: https://clinicaltrials.gov/ct2/show/NCT04647383; Identifier: NCT04647383. CITATION: Cheng JY, Lorch D, Lowe AD, et al. A randomized, double-blind, placebo-controlled, crossover study of respiratory safety of lemborexant in moderate to severe obstructive sleep apnea. J Clin Sleep Med. 2024;20(1):57-65.

Antimicrobial Resistance Profile in ICU Patients Across India: A Multicenter, Retrospective, Observational Study.

Background The pattern of antimicrobial resistance (AMR) changes with time and varies in countries and between hospitals within the same country. Physicians might thus benefit from information on regional resistance patterns of clinically significant bacterial isolates when deciding on the best empirical treatment. Numerous nosocomial infections are caused by multidrug-resistant (MDR) strains, notably methicillin-resistant Staphylococcus aureus (MRSA) strains, which are also linked to higher morbidity and death. Aim Evaluation of AMR profile in intensive care unit (ICU) patients of multiple tertiary care centers across India. Methods This was a multicenter, retrospective study based on electronic laboratory records of microbial isolates from clinical specimens from ICUs analyzed at microbiology laboratories of identified hospitals. Data of invasive sample records was collected from Microbiology labs of the identified hospitals within India and were aligned to WHO 5 Net standard reporting and as per Clinical & Laboratory Standards Institute (CLSI-2014) Guidelines for assessment. Data from 21556 samples were collected retrospectively from December 2021 to January 2010. Antibiotic susceptibility testing was done by using both the Kirby Baur disk diffusion method and the automated method (using the Vitek 2 compact system) as per CLSI (2014) guidelines. Results Of 21,556 enrolled patients, the majority (54.12%) were males and adults (62.07%). The median age was 58 years. Of 815 gram-positive bacteria reports, the commonest were S. aureus (552, 67.73%), Coagulase-negative Staphylococci (107, 13.13%), and Enterococcus spp. (105, 12.88%). For Coagulase-negative Staphylococci-positive samples, resistance was to penicillin (79, 73.83%), and erythromycin (73, 68.22%); and for S. aureus was to ciprofloxacin (361, 65.4%), and erythromycin (315,57.07%). Enterococcus spp. showed maximum resistance to erythromycin (73, 69.52%), followed by ampicillin, ciprofloxacin (68,64.76% each). Of 4,183 gram-negative bacteria reports, the commonest were Klebsiella pneumoniae (1,531, 36.6%), Escherichia coli (1,269, 30.34%), and Acinetobacter spp. (589, 14.08%), Pseudomonas aeruginosa (438, 14.08%), other Klebsiella spp. (174, 4.16%) and Enterobacter spp. (161, 3.85%). K. pneumoniae showed resistance to ciprofloxacin (1,001, 65.38%). E. coli showed resistance to ampicillin (918, 72.34%), and ciprofloxacin (798,62.88%); and Acinetobacter spp. to ceftazidime (525, 89.13%), and ciprofloxacin (507, 86.08%), while P. aeruginosa showed resistance to imipenem (234, 53.42%). Enterobacter spp. showed resistance to cefotaxime (129, 80.12%). MRSA samples showed resistance to phenoxymethylpenicillin (188, 35.54%) and benzylpenicillin (178, 33.46%). Conclusion Gram-negative bacteria were more common than gram-positive bacteria in causing antibiotic-resistant infections in ICU, with beta-lactams, fluoroquinolones, macrolides, and cephalosporins showing varied percentages of resistance. Fluoroquinolones, macrolides, and penicillin were noted to be highly resistant against gram-positive species. This indicates that evaluation based on MDR and antibiotic consumption patterns is imperative.

Decreasing Prescribing Errors in Antimicrobial Stewardship Program-Restricted Medications.

OBJECTIVES: Antimicrobial stewardship programs (ASPs) restrict prescribing practices to regulate antimicrobial use, increasing the risk of prescribing errors. This quality improvement project aimed to decrease the proportion of prescribing errors in ASP-restricted medications by standardizing workflow. METHODS: The study took place on all inpatient units at a tertiary care children's hospital between January 2020 and February 2022. Patients <22 years old with an order for an ASP-restricted medication course were included. An interprofessional team used the Model for Improvement to design interventions targeted at reducing ASP-restricted medication prescribing errors. Plan-Do-Study-Act cycles included standardizing communication and medication review, implementing protocols, and developing electronic health record safety nets. The primary outcome was the proportion of ASP-restricted medication orders with a prescribing error. The secondary outcome was time between prescribing errors. Outcomes were plotted on control charts and analyzed for special cause variation. Outcomes were monitored for a 3-month sustainability period. RESULTS: Nine-hundred ASP-restricted medication orders were included in the baseline period (January 2020-December 2020) and 1035 orders were included in the intervention period (January 2021-February 2022). The proportion of prescribing errors decreased from 10.9% to 4.6%, and special cause variation was observed in Feb 2021. Mean time between prescribing errors increased from 2.9 days to 8.5 days. These outcomes were sustained. CONCLUSIONS: Quality improvement methods can be used to achieve a sustained reduction in the proportion of ASP-restricted medication orders with a prescribing error throughout an entire children's hospital.

Intermediate partitioning kinetic isotope effects for the NIH shift of 4-hydroxyphenylpyruvate dioxygenase and the hydroxylation reaction of hydroxymandelate synthase reveal mechanistic complexity.

4-Hydroxyphenylpyruvate dioxygenase (HPPD) and hydroxymandelate synthase (HMS) are similar enzymes that catalyze complex dioxygenation reactions using the substrates 4-hydroxyphenylpyruvate (HPP) and dioxygen. Both enzymes decarboxylate HPP and then hydroxylate the resulting hydroxyphenylacetate (HPA). The hydroxylation reaction catalyzed by HPPD displaces the aceto substituent of HPA in a 1,2-shift to form 2,5-dihydroxyphenylacetate (homogentisate, HG), whereas the hydroxylation reaction of HMS places a hydroxyl on the benzylic carbon forming 3'-hydroxyphenylacetate (S-hydroxymandelate, HMA) without ensuing chemistry. The wild-type form of HPPD and variants of both enzymes uncouple to form both native and non-native products. We have used intermediate partitioning to probe bifurcating steps that form these products by substituting deuteriums for protiums at the benzylic position of the HPP substrate. These substitutions result in altered ratios of products that can be used to calculate kinetic isotope effects (KIE) for the formation of a specific product. For HPPD, secondary normal KIEs indicate that cleavage of the bond in the displacement reaction prior to the shift occurs by a homolytic mechanism. NMR analysis of HG derived from HPPD reacting with enantiomerically pure R-3'-deutero-HPP indicates that no rotation about the bond to the radical occurs, suggesting that collapse of the biradical intermediate is rapid. The production of HMA was observed in HMS and HPPD variant reactions. HMS hydroxylates to form exclusively S-hydroxymandelate. When HMS is reacted with R-3'-deutero-HPP, the observed kinetic isotope effect represents geometry changes in the initial transition state for the nonabstracted proton. These data show evidence of sp(3) hybridization in a HPPD variant and sp(2) hybridization in HMS variants, suggesting that HMS stabilizes a more advanced transition state in order to catalyze H-atom abstraction.