Control of the flagellation pattern in Helicobacter pylori by FlhF and FlhG.

FlhF and FlhG control the location and number of flagella, respectively, in many polar-flagellated bacteria. The roles of FlhF and FlhG are not well characterized in bacteria that have multiple polar flagella, such as Helicobacter pylori. Deleting flhG in H. pylori shifted the flagellation pattern where most cells had approximately four flagella to a wider and more even distribution in flagellar number. As reported in other bacteria, deleting flhF in H. pylori resulted in reduced motility, hypoflagellation, and the improper localization of flagella to nonpolar sites. Motile variants of H. pylori ∆flhF mutants that had a higher proportion of flagella localizing correctly to the cell pole were isolated, but we were unable to identify the genetic determinants responsible for the increased localization of flagella to the cell pole. One motile variant though produced more flagella than the ΔflhF parental strain, which apparently resulted from a missense mutation in fliF (encodes the MS ring protein), which changed Asn-255 to aspartate. Recombinant FliFN255D, but not recombinant wild-type FliF, formed ordered ring-like assemblies in vitro that were ~50 nm wide and displayed the MS ring architecture. We infer from these findings that the FliFN225D variant forms the MS ring more effectively in vivo in the absence of FlhF than wild-type FliF. IMPORTANCE Helicobacter pylori colonizes the human stomach where it can cause a variety of diseases, including peptic ulcer disease and gastric cancer. H. pylori uses flagella for motility, which is required for host colonization. FlhG and FlhF control the flagellation patterns in many bacteria. We found that in H. pylori, FlhG ensures that cells have approximately equal number of flagella and FlhF is needed for flagellum assembly and localization. FlhF is proposed to facilitate the assembly of FliF into the MS ring, which is one of the earliest structures formed in flagellum assembly. We identified a FliF variant that assembles the MS ring in the absence of FlhF, which supports the proposed role of FlhF in facilitating MS ring assembly.

A Tripartite Efflux System Affects Flagellum Stability in Helicobacter pylori.

Helicobacter pylori uses a cluster of polar, sheathed flagella for swimming motility. A search for homologs of H. pylori proteins that were conserved in Helicobacter species that possess flagellar sheaths but were underrepresented in Helicobacter species with unsheathed flagella identified several candidate proteins. Four of the identified proteins are predicted to form part of a tripartite efflux system that includes two transmembrane domains of an ABC transporter (HP1487 and HP1486), a periplasmic membrane fusion protein (HP1488), and a TolC-like outer membrane efflux protein (HP1489). Deleting hp1486/hp1487 and hp1489 homologs in H. pylori B128 resulted in reductions in motility and the number of flagella per cell. Cryo-electron tomography studies of intact motors of the Δhp1489 and Δhp1486/hp1487 mutants revealed many of the cells contained a potential flagellum disassembly product consisting of decorated L and P rings, which has been reported in other bacteria. Aberrant motors lacking specific components, including a cage-like structure that surrounds the motor, were also observed in the Δhp1489 mutant. These findings suggest a role for the H. pylori HP1486-HP1489 tripartite efflux system in flagellum stability. Three independent variants of the Δhp1486/hp1487 mutant with enhanced motility were isolated. All three motile variants had the same frameshift mutation in fliL, suggesting a role for FliL in flagellum disassembly.

Comparison of 13 C MRI of hyperpolarized [1-13 C]pyruvate and lactate with the corresponding mass spectrometry images in a murine lymphoma model.

PURPOSE: To compare carbon-13 (13 C) MRSI of hyperpolarized [1-13 C]pyruvate metabolism in a murine tumor model with mass spectrometric (MS) imaging of the corresponding tumor sections in order to cross validate these metabolic imaging techniques and to investigate the effects of pyruvate delivery and tumor lactate concentration on lactate labeling. METHODS: [1-13 C]lactate images were obtained from tumor-bearing mice, following injection of hyperpolarized [1-13 C]pyruvate, using a single-shot 3D 13 C spectroscopic imaging sequence in vivo and using desorption electrospray ionization MS imaging of the corresponding rapidly frozen tumor sections ex vivo. The images were coregistered, and levels of association were determined by means of Spearman rank correlation and Cohen kappa coefficients as well as linear mixed models. The correlation between [1-13 C]pyruvate and [1-13 C]lactate in the MRS images and between [12 C] and [1-13 C]lactate in the MS images were determined by means of Pearson correlation coefficients. RESULTS: [1-13 C]lactate images generated by MS imaging were significantly correlated with the corresponding MRS images. The correlation coefficient between [1-13 C]lactate and [1-13 C]pyruvate in the MRS images was higher than between [1-13 C]lactate and [12 C]lactate in the MS images. CONCLUSION: The inhomogeneous distribution of labeled lactate observed in the MRS images was confirmed by MS imaging of the corresponding tumor sections. The images acquired using both techniques show that the rate of 13 C label exchange between the injected pyruvate and endogenous tumor lactate pool is more correlated with the rate of pyruvate delivery to the tumor cells and is less affected by the endogenous lactate concentration.

Prevalence of ICU Delirium in Postoperative Pediatric Cardiac Surgery Patients.

OBJECTIVES: The objective of this study was to determine the prevalence of ICU delirium in children less than 18 years old that underwent cardiac surgery within the last 30 days. The secondary aim of the study was to identify risk factors associated with ICU delirium in postoperative pediatric cardiac surgical patients. DESIGN: A 1-day, multicenter point-prevalence study of delirium in pediatric postoperative cardiac surgery patients. SETTING: Twenty-seven pediatric cardiac and general critical care units caring for postoperative pediatric cardiac surgery patients in North America. PATIENTS: All children less than 18 years old hospitalized in the cardiac critical care units at 06:00 on a randomly selected, study day. INTERVENTIONS: Eligible children were screened for delirium using the Cornell Assessment of Pediatric Delirium by the study team in collaboration with the bedside nurse. MEASUREMENT AND MAIN RESULTS: Overall, 181 patients were enrolled and 40% (n = 73) screened positive for delirium. There were no statistically significant differences in patient demographic information, severity of defect or surgical procedure, past medical history, or postoperative day between patients screening positive or negative for delirium. Our bivariate analysis found those patients screening positive had a longer duration of mechanical ventilation (12.8 vs 5.1 d; p = 0.02); required more vasoactive support (55% vs 26%; p = 0.0009); and had a higher number of invasive catheters (4 vs 3 catheters; p = 0.001). Delirium-positive patients received more total opioid exposure (1.80 vs 0.36 mg/kg/d of morphine equivalents; p < 0.001), did not have an ambulation or physical therapy schedule (p = 0.02), had not been out of bed in the previous 24 hours (p < 0.0002), and parents were not at the bedside at time of data collection (p = 0.008). In the mixed-effects logistic regression analysis of modifiable risk factors, the following variables were associated with a positive delirium screen: 1) pain score, per point increase (odds ratio, 1.3; 1.06-1.60); 2) total opioid exposure, per mg/kg/d increase (odds ratio, 1.35; 1.06-1.73); 3) SBS less than 0 (odds ratio, 4.01; 1.21-13.27); 4) pain medication or sedative administered in the previous 4 hours (odds ratio, 3.49; 1.32-9.28); 5) no progressive physical therapy or ambulation schedule in their medical record (odds ratio, 4.40; 1.41-13.68); and 6) parents not at bedside at time of data collection (odds ratio, 2.31; 1.01-5.31). CONCLUSIONS: We found delirium to be a common problem after cardiac surgery with several important modifiable risk factors.

Sinorhizobium meliloti CtrA Stability Is Regulated in a CbrA-Dependent Manner That Is Influenced by CpdR1.

UNLABELLED: CbrA is a DivJ/PleC-like histidine kinase of DivK that is required for cell cycle progression and symbiosis in the alphaproteobacterium Sinorhizobium meliloti. Loss of cbrA results in increased levels of CtrA as well as its phosphorylation. While many of the known Caulobacter crescentus regulators of CtrA phosphorylation and proteolysis are phylogenetically conserved within S. meliloti, the latter lacks the PopA regulator that is required for CtrA degradation in C. crescentus. In order to investigate whether CtrA proteolysis occurs in S. meliloti, CtrA stability was assessed. During exponential growth, CtrA is unstable and therefore likely to be degraded in a cell cycle-regulated manner. Loss of cbrA significantly increases CtrA stability, but this phenotype is restored to that of the wild type by constitutive ectopic expression of a CpdR1 variant that cannot be phosphorylated (CpdR1(D53A)). Addition of CpdR1(D53A) fully suppresses cbrA mutant cell cycle defects, consistent with regulation of CtrA stability playing a key role in mediating proper cell cycle progression in S. meliloti. Importantly, the cbrA mutant symbiosis defect is also suppressed in the presence of CpdR1(D53A). Thus, regulation of CtrA stability by CbrA and CpdR1 is associated with free-living cell cycle outcomes and symbiosis. IMPORTANCE: The cell cycle is a fundamental process required for bacterial growth, reproduction, and developmental differentiation. Our objective is to understand how a two-component signal transduction network directs cell cycle events during free-living growth and host colonization. The Sinorhizobium meliloti nitrogen-fixing symbiosis with plants is associated with novel cell cycle events. This study identifies a link between the regulated stability of an essential response regulator, free-living cell cycle progression, and symbiosis.

Primary healthcare needs and barriers to care among Calgary's homeless populations.

BACKGROUND: Despite Canada's universal healthcare system, significant barriers impede individuals experiencing homelessness from accessing health services. Furthermore, there is a paucity in the qualitative literature describing how Canadians experiencing homelessness access health care services. Our objective was to qualitatively explore perceived healthcare needs and barriers among individuals experiencing homelessness in one large Canadian city - Calgary, Alberta. METHODS: We conducted a qualitative descriptive study that included open-ended interviews and focus groups with a variety of stakeholders who are involved in healthcare among Calgary's homeless populations. These included individuals experiencing homelessness (n = 11) as well as employees from several healthcare service providers for those experiencing homelessness (n = 11). Transcripts from these interviews were thematically analyzed by two analysts. RESULTS: Stakeholder interviews yielded several pervasive themes surrounding the health care needs of the homeless and barriers to accessing care. Some of the primary health care needs which were identified included mental health, addictions, and allied health as well as care that addresses the social determinants of health. Notably, it was difficult for many stakeholders to pinpoint specific health care priorities, as they identified that the health care needs among Calgary's homeless populations are diverse and complex, often even describing the needs as overwhelming. Types of barriers to primary care that were identified by stakeholders included: emotional, educational, geographical, financial and structural barriers, as well as discrimination. CONCLUSIONS: Our findings highlight the diverse primary health care needs of Calgary's homeless populations. Despite the fact that Canada has a universal publicly funded health care system, individuals experiencing homelessness face significant barriers in accessing primary care.

Mural and extramural venous invasion and prognosis in colorectal cancer.

BACKGROUND: Extramural venous invasion is a known independent predictor of poor prognosis after resection of colorectal adenocarcinoma, but the prognostic value of mural venous invasion alone and the association between venous invasion and prognosis within tumor stages has received little research attention. OBJECTIVE: This study aimed to determine whether associations between mural and extramural venous invasion and outcome differ among tumor stages after adjustment for other factors known to influence prognosis. DESIGN: This study is a retrospective analysis of prospectively collected data. SETTINGS: Data were drawn from a registry of 3040 consecutive patients undergoing resection between 1980 and 2005 under the care of specialist surgeons in a tertiary referral public hospital and an affiliated private hospital. A standardized protocol was used for the pathological assessment of specimens. MAIN OUTCOME MEASURES: The primary outcomes measured were overall survival, cancer-specific survival, and recurrence. RESULTS: There was no significant association between venous invasion and survival in stages A (n = 544) or B (n = 1078). In stage C (n = 899), overall survival time was significantly shorter in patients with mural invasion alone or extramural invasion (both p < 0.001) than in those without invasion, and this persisted after adjustment for other prognostic variables. Equivalent bivariate associations were found in stage D, but only the effect of extramural invasion persisted after adjustment. LIMITATIONS: Our findings arise from the experience of a single surgical group and may not be generalizable to other settings. Only hematoxylin and eosin staining was used. CONCLUSIONS: The association between venous invasion and prognosis was stage specific. Both mural venous invasion alone and extramural venous invasion independently predicted overall survival in patients with stage C tumors, but not in patients with stages A, B, or D tumors. Although mural invasion alone was rare, the separate reporting of both mural and extramural invasion in patients with stage C tumor is informative and desirable.

Proposed clinical operative synoptic report for ileocolic resection for Crohn's disease.

BACKGROUND: Crohn's disease patients may require multiple surgeries during their lifetime. Because operative reports are not standardized, information relevant to future management may not be documented. Synoptic reports used in other fields such as histopathology have proven to be effective and allow consistent documentation of results. The aim of this study was to retrospectively review the completeness of the operative reports for ileocolic Crohn's resections (ICR) and to propose a synoptic report. METHODS: A draft synoptic operative report for ICR for Crohn's disease was presented in the IBD multidisciplinary meeting and a Delphi process used to gain consensus for inclusion in the synoptic report. Retrospective analysis of consecutive ICR from January 2010 to April 2023 was undertaken to determine the presence of the standardized criteria. RESULTS: A total of 66 ICR were performed in 63 patients during the study period. No operation reports were excluded. The examination of bowel for macroscopic disease was partially documented in 88% cases. The extent of mesenteric resection and any difficulty encountered during dissection were poorly documented. The remaining length of small and large intestines was not documented in most operative reports. The clinical sections that were compulsory entrance in the electronic operative report achieved 100% compliance. CONCLUSION: This study has demonstrated that key information was often deficient in the operative report. This may have a significant impact on the future management of Crohn's patients and affects the interpretation of research outcomes. A proposed clinical synoptic operative report is easy to use and ensures compliance.

The Sinorhizobium meliloti sensor histidine kinase CbrA contributes to free-living cell cycle regulation.

Sinorhizobium meliloti is alternately capable of colonizing the soil as a free-living bacterium or establishing a chronic intracellular infection with its legume host for the purpose of nitrogen fixation. We previously identified the S. meliloti two-component sensor histidine kinase CbrA as playing an important role in regulating exopolysaccharide production, flagellar motility and symbiosis. Phylogenetic analysis of CbrA has highlighted its evolutionary relatedness to the Caulobacter crescentus sensor histidine kinases PleC and DivJ, which are involved in CtrA-dependent cell cycle regulation through the shared response regulator DivK. We therefore became interested in testing whether CbrA plays a role in regulating S. meliloti cell cycle processes. We find the loss of cbrA results in filamentous cell growth accompanied by cells that contain an aberrant genome complement, indicating CbrA plays a role in regulating cell division and possibly DNA segregation. S. meliloti DivK localizes to the old cell pole during distinct phases of the cell cycle in a phosphorylation-dependent manner. Loss of cbrA results in a significantly decreased rate of DivK polar localization when compared with the wild-type, suggesting CbrA helps regulate cell cycle processes by modulating DivK phosphorylation status as a kinase. Consistent with a presumptive decrease in DivK phosphorylation and activity, we also find the steady-state level of CtrA increased in cbrA mutants. Our data therefore demonstrate that CbrA contributes to free-living cell cycle regulation, which in light of its requirement for symbiosis, points to the potential importance of cell cycle regulation for establishing an effective host interaction.

The role of a student-run clinic in providing primary care for Calgary's homeless populations: a qualitative study.

BACKGROUND: Despite the increasing popularity of Student-Run Clinics (SRCs) in Canada, there is little existing literature exploring their role within the Canadian healthcare system. Generalizing American literature to Canadian SRCs is inappropriate, given significant differences in healthcare delivery between the two countries. Medical students at the University of Calgary started a SRC serving Calgary's homeless population at the Calgary Drop-In and Rehabilitation Centre (CDIRC). This study explored stakeholders' desired role for a SRC within Calgary's primary healthcare system and potential barriers it may face. METHODS: Individual and group semi-structured interviews were undertaken with key stakeholders in the SRC project: clients (potential patients), CDIRC staff, staff from other stakeholder organizations, medical students, and faculty members. Convenience sampling was used in the recruitment of client participants. Interview transcripts were analyzed using a coding template which was derived from the literature. RESULTS: Participants identified factors related to the clinic and to medical students that suggest there is an important role for a SRC in Calgary. The clinic was cited as improving access to primary healthcare for individuals experiencing homelessness. It was suggested that students may be ideally suited to provide empathetic healthcare to this population. Barriers to success were identified, including continuity of care and the exclusion of some subsets of the homeless population due to location. CONCLUSIONS: SRCs possess several unique features that may make them a potentially important primary healthcare resource for the homeless. Participants identified numerous benefits of the SRC to providing primary care for homeless individuals, as well as several important limitations that need to be accounted for when designing and implementing such a program.

FlgV forms a flagellar motor ring that is required for optimal motility of Helicobacter pylori.

Flagella-driven motility is essential for Helicobacter pylori to colonize the human stomach, where it causes a variety of diseases, including chronic gastritis, peptic ulcer disease, and gastric cancer. H. pylori has evolved a high-torque-generating flagellar motor that possesses several accessories not found in the archetypical Escherichia coli motor. FlgV was one of the first flagellar accessory proteins identified in Campylobacter jejuni, but its structure and function remain poorly understood. Here, we confirm that deletion of flgV in H. pylori B128 and a highly motile variant of H. pylori G27 (G27M) results in reduced motility in soft agar medium. Comparative analyses of in-situ flagellar motor structures of wild-type, ΔflgV, and a strain expressing FlgV-YFP showed that FlgV forms a ring-like structure closely associated with the junction of two highly conserved flagellar components: the MS and C rings. The results of our studies suggest that the FlgV ring has adapted specifically in Campylobacterota to support the assembly and efficient function of the high-torque-generating motors.

Mastery moderates the negative effect of stigma on depressive symptoms in people living with HIV.

Stigma continues to have a negative effect on the care, treatment, and support of people living with HIV. This study presents baseline data from 825 participants taking part in a cohort study that collects data on the clinical profile and social determinants of health of people with HIV. We performed multivariate regression analysis to evaluate whether mastery and social support moderated the negative effect of stigma on depressive symptoms. Stigma was associated with depressive symptoms after controlling for potential demographic and clinical confounders. In addition, higher levels of mastery and social support were associated with lower levels of depression. However, only mastery moderated the negative effects of stigma on depressive symptoms. For individuals with high levels of mastery, greater exposure to stigma does not translate into greater distress. Interventions targeting the mental health concerns of people with HIV should increase their focus on improving people' sense of personal control.

Toward Rapid Aspartic Acid Isomer Localization in Therapeutic Peptides Using Cyclic Ion Mobility Mass Spectrometry.

There is an increasing emphasis on the critical evaluation of interbatch purity and physical stability of therapeutic peptides. This is due to concerns over the impact that product- and process-related impurities may have on safety and efficacy of this class of drug. Aspartic acid isomerization to isoaspartic acid is a common isobaric impurity that can be very difficult to identify without first synthesizing isoAsp peptide standards for comparison by chromatography. As such, analytical tools that can determine if an Asp residue has isomerized, as well as the site of isomerization within the peptide sequence, are highly sought after. Ion mobility-mass spectrometry is a conformation-selective method that has developed rapidly in recent years particularly with the commercialization of traveling wave ion mobility instruments. This study employed a cyclic ion mobility (cIMS) mass spectrometry system to investigate the conformational characteristics of a therapeutic peptide and three synthetic isomeric forms, each with a single Asp residue isomerized to isoAsp. cIMS was able to not only show distinct conformational differences between each peptide but crucially, in conjunction with a simple workflow for comparing ion mobility data, it correctly located which Asp residue in each peptide had isomerized to isoAsp. This work highlights the value of cIMS as a potential screening tool in the analysis of therapeutic peptides prone to the formation of isoAsp impurities.

'Fight the parasite': raising awareness of cystic echinococcosis in primary school children in endemic countries.

BACKGROUND: Cystic echinococcosis (CE) is a widespread zoonosis and a significant economic concern and cause of morbidity in humans. A scarcity of education on the sources of CE infection and containment measures is considered to be a key factor responsible for persistent transmission within communities. Recently, edutainment approaches have captured the attention of health education (HE) professionals due to the benefits of integrating cognitive and emotional learning processes. METHODS: A study was carried out in Sardinia, Italy, between 2020 and 2022, amid the SARS-Covid-19 pandemic. The project, designed to involve primary school children (via remote or face-to-face learning depending on the evolving Covid-19 containment measures) consisted of four distinct phases: (i) creation of material for school children and teachers focused on cystic echinococcosis; (ii) pre-intervention evaluation of CE knowledge (i.e. True False Don't Know [TFD] pre-intervention questionnaire based on CE-related knowledge and practices); (iii) edutainment activity (e.g. interactive lessons enhanced by the comic booklet and the "Fight the parasite" cartoon video, hands-on educational activities and drawing activities on CE); and (iv) post-intervention evaluation of CE knowledge (via TFD post-intervention questionnaire [same questionnaire as used for the pre-intervention assessment] on CE-related knowledge and practices) and on-site edutainment tour in primary schools taking part to the project. RESULTS: The percentage of correct answers increased from 65% for the questionnaire administered pre-intervention to 87.9% for the same questionnaire administered post-intervention (χ2 = 648.12, df = 1, P < 0.0001), while the percentage of uncertain answers (i.e. 'I don't know') decreased from 23% pre-intervention to 5% post-intervention (χ2 = 603.44, df = 1, P < 0.0001). These differences indicate a significantly enhanced understanding of CE among participating school children after the intervention. CONCLUSIONS: The results of the present survey indicate that the use of digital educational tools, the use of video animations as a model for science communication, as well as other participatory teaching methods, enabled children to retain key knowledge of the routes of CE transmission and ways to prevent it.

The use of the radiographic appearance of the azygos vein to assess volume status in trauma patients.

BACKGROUND: The assessment of hypovolemia in victims of trauma is a critical aspect of resuscitation and care in the initial presentation of a patient. This study attempted to validate the use of the appearance of the azygos vein (AV) on initial chest radiographs as a parameter that may add to this initial assessment. METHODS: The design involved a blinded independent assessment of serial chest radiographs from consecutive trauma cases from January 21, 2008, until September 13, 2008, by a trained Radiologist and a Trauma Team Leader (TTL) and then comparing this assessment to mean arterial pressure (MAP) and heart rate estimates of volume status in serial severe trauma patients. This is an insensitive but specific measure of volume status. RESULTS: In this population with high prevalence of hypovolemia, the presence of an AV ≤ 0.5 cm yielded a sensitivity of 4.9% and 9.8% for the TTL and Radiologist, respectively, in patients with a mean arterial pressure <70 and heart rate >100. The specificity was 98.8% and 91.6%, which translates into a positive likelihood ratio of 4.08 and 1.17 for the TTL and Radiologist, respectively. The Kappa score for agreement between the two readers was 0.4. CONCLUSION: When a small AV can be seen by the TTL, it may be a useful adjunct to the assessment of volume status.

Inequalities in determinants of health among Aboriginal and Caucasian persons living with HIV/AIDS in Ontario: results from the Positive Spaces, Healthy Places Study.

OBJECTIVES: Aboriginal Canadians (i.e., First Nations, Inuit and Métis) are disproportionately affected by HIV/AIDS, and experience greater social and economic marginalization and poorer housing conditions. This study sought to understand the differences in the determinants of health and housing-related characteristics between samples of Aboriginal and Caucasian adults living with HIV/AIDS in Ontario. METHODS: We analyzed baseline demographic, socio-economic, health, and housing-related data from 521 individuals (79 Aboriginal and 442 Caucasian) living with HIV/AIDS and enrolled in the Positive Spaces, Healthy Places study. We compared the characteristics of Aboriginal and Caucasian participants to identify determinants of health and housing-related characteristics independently associated with Aboriginal ethnicity. RESULTS: Compared to Caucausian participants living with HIV, Aboriginal participants were more likely to be younger, female or transgender women, less educated, unemployed, and homeless or unstably housed. They were also more likely to have low incomes and to have experienced housing-related discrimination. In a multivariate model, gender, income, and experiences of homelessness were independently associated with Aboriginal ethnicity. CONCLUSION: Aboriginal individuals living with HIV/AIDS in our sample are coping with significantly worse social and economic conditions and are more likely to experience challenging housing situations than a comparison group of Caucasian individuals living with HIV/AIDS. To develop effective care, treatment and support strategies for Aboriginal peoples with HIV, it is critical to address and improve their socio-economic and housing conditions.

Novel Development of Predictive Feature Fingerprints to Identify Chemistry-Based Features for the Effective Drug Design of SARS-CoV-2 Target Antagonists and Inhibitors Using Machine Learning.

A unique approach to bioactivity and chemical data curation coupled with random forest analyses has led to a series of target-specific and cross-validated predictive feature fingerprints (PFF) that have high predictability across multiple therapeutic targets and disease stages involved in the severe acute respiratory syndrome due to coronavirus 2 (SARS-CoV-2)-induced COVID-19 pandemic, which include plasma kallikrein, human immunodeficiency virus (HIV)-protease, nonstructural protein (NSP)5, NSP12, Janus kinase (JAK) family, and AT-1. The approach was highly accurate in determining the matched target for the different compound sets and suggests that the models could be used for virtual screening of target-specific compound libraries. The curation-modeling process was successfully applied to a SARS-CoV-2 phenotypic screen and could be used for predictive bioactivity estimation and prioritization for clinical trial selection; virtual screening of drug libraries for the repurposing of drug molecules; and analysis and direction of proprietary data sets.

Neuropsychological case report of MCI reversion at one-year follow-up.

This report presents the neuropsychological profile of an older gentleman diagnosed with single-domain mild cognitive impairment (MCI) at baseline who reverted to normal cognitive functioning at 1-year follow-up. The case highlights important considerations for assessing and diagnosing MCI in clinical settings in the context of sizeable reversion rates that have been reported extensively in the literature. A 72-year-old gentleman presented to our Neuropsychology Clinic with subjective memory complaints. Per recommendation, the patient returned for follow-up testing 1-year later. A clinical interview, comprehensive battery of neuropsychological tests, and mood questionnaires were administered during both evaluations. At baseline, DSM-5 Mild Neurocognitive Disorder consistent with single-domain amnestic MCI was diagnosed based on several impaired scores on the California Verbal Learning Test, 2nd version (CVLT-II) and collateral report of subtle decline in functioning. At follow-up, all cognitive performances fell within normal limits. The patient no longer met criteria for Mild Neurocognitive Disorder. The present case study highlights important considerations when assessing and diagnosing MCI in the clinical setting. Repeat testing in clinical settings is underscored by the sizeable rate of MCI reversion reported in the literature. Important diagnostic and feedback considerations are discussed.

Macrophage killing of Leishmania amazonensis amastigotes requires both nitric oxide and superoxide.

The requirements for effective and efficient intracellular killing of Leishmania amazonensis by activated macrophages are unknown. Despite resistance to the arginase inhibitor LOHA by intracellular L. amazonensis amastigotes, enhanced replication did not account for the relative resistance of this parasite to macrophage activation. Herein we report that the presence of both superoxide and nitric oxide is necessary for efficient killing of L. amazonensis amastigotes within LPS/IFN-gamma-activated bone marrow-derived macrophages generated from C3H mice. Addition of an extracellular signal-regulated kinase (ERK) inhibitor to L. amazonensis-infected macrophages increased the ability of these activated macrophages to kill L. amazonensis amastigotes. This enhanced macrophage killing through addition of ERK inhibitor was abrogated by inhibition of superoxide or iNOS, whereas inhibiting superoxide had no effect on the killing of L. major. These results suggest that ERK activation may modulate effective macrophage killing, leading to the ability of L. amazonensis to resist elimination within activated macrophages.