Mass online training of health care workers during COVID-19: approach, impact, and outcomes for over 10,000 health care providers.

OBJECTIVES: COVID-19 revealed major shortfalls in healthcare workers (HCWs) trained in acute and critical care worldwide, especially in low-resource settings. We aimed to assess mass online courses' efficacy in preparing HCWs to manage COVID-19 patients and to determine whether rapidly deployed e-learning can enhance their knowledge and confidence during a pandemic. STUDY DESIGN: Retrospective cohort study. METHODS: This international retrospective cohort study, led by a large Academic Medical Centre (AMC), was conducted via YouTube and the AMC's online learning platform. From 2020 to 2021, multidisciplinary experts developed and deployed six online training courses based on the latest evidence-based management guidelines. Participants were selected through a voluntary sample following an electronic campaign. Training outcomes were assessed using pre-and post-test questionnaires, evaluation forms, and post-training assessment surveys. Kirkpatrick's Model guided training evaluation to measure self-reported knowledge, clinical skills, and confidence improvement. We also captured the number and type of COVID-19 patients managed by HCWs after the trainings. RESULTS: Every 22.8 reach/impression and every 1.2 engagements led to a course registration. The 10,425 registrants (56.8% female, 43.1% male) represented 584 medical facilities across 154 cities. The largest segments of participants were students/interns (20.6%) and medical officers (13.4%). Of the 2169 registered participants in courses with tests, 66.9% completed post-tests. Test scores from all courses increased from the initial baseline to subsequent improvement post-course. Participants completing post-training assessment surveys reported that the online courses improved their knowledge and clinical skills (83.5%) and confidence (89.4%). Respondents managed over 19,720 COVID-19 patients after attending the courses, with 47.7% patients being moderately/severely ill. CONCLUSIONS: Participants' confidence in handling COVID-19 patients is increased by rapidly deploying mass training to a substantial target population through digital tools. The findings present a virtual education and assessment model that can be leveraged for future global public health issues, and estimates for future electronic campaigns to target.

A Clinicopathological Study of Various Oral Cancer Diagnostic Techniques.

Oral cancer is one of the most commonly occurring malignant tumors in the head and neck regions with high incident rate and mortality rate in the developed countries than in the developing countries. Generally, the survival rate of cancer patients may increase when diagnosed at early stage, followed by prompt treatment and therapy. Recently, cancer diagnosis and therapy design for a specific cancer patient have been performed with the advanced computer-aided techniques. The responses of the cancer therapy could be continuously monitored to ensure the effectiveness of the treatment process that hardly requires diagnostic result as quick as possible to improve the quality and patient care. This paper gives an overview of oral cancer occurrence, different types, and various diagnostic techniques. In addition, a brief introduction is given to various stages of immunoanalysis including tissue image preparation, whole slide imaging, and microscopic image analysis.

Massive expanding hematoma of the chin following blunt trauma.

Posttraumatic hematoma of the face is common and usually self-limiting in nature. We report an unusual massive expanding hematoma of the chin within 9 h following a blunt trauma with no associated injuries or fracture.

Estimation of salivary ß-glucuronidase activity as a marker of periodontal disease: A case control study.

AIM: The aim of the present study was to estimate the salivary ß-glucuronidase level in healthy and diseased periodontium and to correlate the level with clinical measurement. MATERIALS AND METHODS: 70 patients were included in this study with the age ranging from 30 to 65 years. Both males and females were included. They were divided into two groups: Control having healthy periodontium (n = 20) and experimental having diseased periodontium (n = 50). The parameters recorded were probing pocket depth, probing attachment level, gingival index, ß-glucuronidase activity in the saliva, number of white blood cells, neutrophils, lymphocytes count, and platelet count. RESULTS: It was observed that there was an increase in the level of salivary ß-glucuronidase in the experimental subjects than in the control patients, and a significant positive linear relationship existed between salivary ß-glucuronidase level and probing pocket depth in the experimental group. CONCLUSION: Level of salivary ß-glucuronidase increases during inflammation in the periodontium.

Coupling endoplasmic reticulum stress to the cell-death program: a novel HSP90-independent role for the small chaperone protein p23.

The endoplasmic reticulum (ER) is the principal organelle for the biosynthesis of proteins, steroids and many lipids, and is highly sensitive to alterations in its environment. Perturbation of Ca(2+) homeostasis, elevated secretory protein synthesis, deprivation of glucose or other sugars, altered glycosylation and/or the accumulation of misfolded proteins may all result in ER stress, and prolonged ER stress triggers cell death. Studies from multiple laboratories have identified the roles of several ER stress-induced cell-death modulators and effectors through the use of biochemical, pharmacological and genetic tools. In the present work, we describe the role of p23, a small chaperone protein, in preventing ER stress-induced cell death. p23 is a highly conserved chaperone protein that modulates HSP90 activity and is also a component of the steroid receptors. p23 is cleaved during ER stress-induced cell death; this cleavage, which occurs close to the carboxy-terminus, requires caspase-3 and/or caspase-7, but not caspase-8. Blockage of the caspase cleavage site of p23 was associated with decreased cell death induced by ER stress. Immunodepletion of p23 or inhibition of p23 expression by siRNA resulted in enhancement of ER stress-induced cell death. While p23 co-immunoprecipitated with the BH3-only protein PUMA (p53-upregulated modulator of apoptosis) in untreated cells, prolonged ER stress disrupted this interaction. The results define a protective role for p23, and provide further support for a model in which ER stress is coupled to the mitochondrial intrinsic apoptotic pathway through the activities of BH3 family proteins.

Signaling lymphocytic activation molecule is expressed on CD40 ligand-activated dendritic cells and directly augments production of inflammatory cytokines.

Dendritic cells (DC) comprise a key part of the innate immune system that, upon activation, profoundly influences the nature of the adaptive T cell response. In this study, we present evidence that signaling lymphocytic activation molecule (SLAM), a molecule first identified in activated T and B cells, is strongly up-regulated in DC activated through CD40, as well as in response to inflammatory stimuli, including polyinosinic polycytidylic acid and LPS. mRNA encoding both membrane-bound and soluble secreted isoforms of SLAM was detected in CD40 ligand-activated DC, comprising two of the four known SLAM isoforms. Expression of membrane-bound SLAM protein peaked at 12 h poststimulation with CD40 ligand, gradually returning to baseline levels after 6 days. SLAM up-regulation appears to be a direct result of the induction of DC maturation, as inflammatory cytokines released during this process do not affect SLAM expression. Functionally, engagement of SLAM enhances DC production of IL-12 and IL-8, while having no effect on production of IL-10. Because SLAM is involved in the activation of T cells, the expression of SLAM on DC may provide a bidirectional signaling mechanism in which interacting DC and T cells are simultaneously and synergistically activated to mount proinflammatory Th1 responses.

The A' and F' pockets of human CD1b are both required for optimal presentation of lipid antigens to T cells.

CD1 proteins are unique in their ability to present lipid Ags to T cells. Human CD1b shares significant amino acid homology with mouse CD1d1, which contains an unusual putative Ag-binding groove formed by two large hydrophobic pockets, A' and F'. We investigated the function of the amino acid residues that line the A' and F' pockets of CD1b by engineering 36 alanine-substitution mutants and analyzing their ability to present mycobacterial glycolipid Ags. Two lipid Ags presented by CD1b were studied, a naturally occurring glucose monomycolate (GMM) isolated from mycobacteria, which contains two long alkyl chains (C54-C62 and C22-C24) and synthetic GMM (sGMM), which includes two short alkyl chains (C18 and C14). We identified eight residues in both the A' and F' pockets that were involved in the presentation of both GMM and sGMM to T cells. Interestingly, four additional residues located in the distal portion of the A' pocket were required for the optimal presentation of GMM, but not sGMM. Conversely, nine residues located between the center of the groove and the F' pocket were necessary for the optimal presentation of sGMM, but not GMM. These data indicate that both the A' and F' pockets of human CD1b are required for the presentation of lipid Ags to T cells.

Molecular recognition of human CD1b antigen complexes: evidence for a common pattern of interaction with alpha beta TCRs.

Ag-specific T cell recognition is mediated through direct interaction of clonotypic TCRs with complexes formed between Ag-presenting molecules and their bound ligands. Although characterized in substantial detail for class I and class II MHC encoded molecules, the molecular interactions responsible for TCR recognition of the CD1 lipid and glycolipid Ag-presenting molecules are not yet well understood. Using a panel of epitope-specific Abs and site-specific mutants of the CD1b molecule, we showed that TCR interactions occur on the membrane distal aspects of the CD1b molecule over the alpha1 and alpha2 domain helices. The location of residues on CD1b important for this interaction suggested that TCRs bind in a diagonal orientation relative to the longitudinal axes of the alpha helices. The data point to a model in which TCR interaction extends over the opening of the putative Ag-binding groove, making multiple direct contacts with both alpha helices and bound Ag. Although reminiscent of TCR interaction with MHC class I, our data also pointed to significant differences between the TCR interactions with CD1 and MHC encoded Ag-presenting molecules, indicating that Ag receptor binding must be modified to accommodate the unique molecular structure of the CD1b molecule and the unusual Ags it presents.

An antimicrobial activity of cytolytic T cells mediated by granulysin.

Cytolytic T lymphocytes (CTLs) kill intracellular pathogens by a granule-dependent mechanism. Granulysin, a protein found in granules of CTLs, reduced the viability of a broad spectrum of pathogenic bacteria, fungi, and parasites in vitro. Granulysin directly killed extracellular Mycobacterium tuberculosis, altering the membrane integrity of the bacillus, and, in combination with perforin, decreased the viability of intracellular M. tuberculosis. The ability of CTLs to kill intracellular M. tuberculosis was dependent on the presence of granulysin in cytotoxic granules, defining a mechanism by which T cells directly contribute to immunity against intracellular pathogens.

Down-regulation of CD1 on antigen-presenting cells by infection with Mycobacterium tuberculosis.

Intracellular pathogens have developed efficient evasion strategies to survive the defenses of the host immune system. In this study, we describe a new escape mechanism utilized by Mycobacterium tuberculosis that involves the down-regulation of the Ag-presenting molecule CD1 from the cell surface of CD1+ APCs. The loss of CD1 from the cell surface is associated with a complete inhibition of the ability of the infected cells to present Ag to CD1-restricted T cells. The down-regulation of Ag-presenting molecules on CD1+ APC by infection with M. tuberculosis is unique for CD1, since the expression of the classical Ag-presenting molecules MHC class I and MHC class II is not influenced. Our data show that efficient down-regulation of CD1 requires infection of the cells with live mycobacteria, since heat killing of the bacteria completely abrogates the effect. The observed down-regulation is not due to the secretion of cytokines or other host- or pathogen-derived factors. Investigation of upstream events responsible for the down-regulation of CD1 revealed that infection with live M. tuberculosis decreased the steady state CD1-mRNA levels. This study introduces a novel evasion mechanism of M. tuberculosis that could contribute to persistence of intracellular infection by avoiding immune recognition.

Molecular interaction of CD1b with lipoglycan antigens.

The ability of human CD1b molecules to present nonpeptide antigens is suggested by the T cell recognition of microbial lipids and lipoglycans in the presence of CD1b-expressing antigen-presenting cells. We demonstrate the high-affinity interaction of CD1b molecules with the acyl side chains of known T cell antigens, lipoarabinomannan, phosphatidylinositol mannoside, and glucose monomycolate. Furthermore, CD1b-antigen binding was optimal at acidic pH, consistent with the known requirement for endosomal acidification in CD1b-restricted antigen presentation. The mechanism for CD1b-ligand interaction involves the partial unfolding of the alpha helices of CD1b at acidic pH, revealing a hydrophobic binding site that could accommodate lipid. These data provide direct evidence that the CD1b molecule has evolved unique biochemical properties that enable the binding of lipid-containing antigens from intracellular pathogens.

The tyrosine-containing cytoplasmic tail of CD1b is essential for its efficient presentation of bacterial lipid antigens.

CD1b is an antigen-presenting molecule that mediates recognition of bacterial lipid and glycolipid antigens by specific T cells. We demonstrate that the nine-amino acid cytoplasmic tail of CD1b contains all of the signals required for its normal endosomal targeting, and that the single cytoplasmic tyrosine is a critical component of the targeting motif. Mutant forms of CD1b lacking the endosomal targeting motif are expressed at high levels on the cell surface but are unable to efficiently present lipid antigens acquired either exogenously or from live intracellular organisms. These results define the functional role of the CD1b targeting motif in a physiologic setting and demonstrate its importance in delivery of this antigen-presenting molecule to appropriate intracellular compartments.

Transient and selectable transformation of the parasitic protist Trichomonas vaginalis.

We have developed methods to transiently and selectably transform the human-infective protist Trichomonas vaginalis. This parasite, a common cause of vaginitis worldwide, is one of the earlier branching eukaryotes studied to date. We have introduced three heterologous genes into T. vaginalis by electroporation and have used the 5' and 3' untranslated regions of the endogenous gene alpha-succinyl CoA synthetase B (alpha-SCSB) to drive transcription of these genes. Transient expression of two reporter proteins, chloramphenicol acetyltransferase (CAT) or luciferase, was detected when electroporating in the presence of 50 microg closed-circular construct. Optimal levels of expression were observed using approximately 2.5 x 10(8) T. vaginalis cells and 350 volts, 960 microFd for electroporation; however, other conditions also led to significant reporter gene expression. A time course following the expression of CAT in T. vaginalis transient transformants revealed the highest level of expression 8-21 hr postelectroporation and showed that CAT activity is undetectable using TLC by 99 hr postelectroporation. The system we established to obtain selectable transformants uses the neomycin phosphotransferase (neo) gene as the selectable marker. Cells electroporated with 20 microg of the NEO construct were plated in the presence of 50 microg/ml paromomycin and incubated in an anaerobic chamber. The paromomycin-resistant colonies that formed within 3-5 days were cultivated in the presence of drug and DNA was isolated for analyses. The NEO construct was shown to be maintained episomally, as a closed-circle, at between 10-30 copies per cell. The ability to transiently and selectably transform T. vaginalis should greatly enhance research on this important human parasite.

Detailed angiographic analysis of high-speed mechanical rotational atherectomy in human coronary arteries.

BACKGROUND: Several types of atherectomy devices have been developed recently for treatment of patients with ischemic heart disease. METHODS AND RESULTS: Mechanical rotational atherectomy (MRA) using a high-speed rotational burr (Rotablator) was performed on 116 lesions in 104 patients. MRA alone was performed in 27 lesions (23%), and conventional balloon angioplasty (PTCA) was performed after MRA in 89 lesions (77%). Diameter stenosis decreased from 70 +/- 13% before MRA to 54 +/- 23% after MRA, and the final diameter stenosis (after MRA alone or with adjunctive PTCA) was 30 +/- 20% (P < .001). Minimal lumen diameter increased from 1.0 +/- 0.5 mm before MRA to 1.4 +/- 0.7 mm after MRA, and the final minimal lumen diameter was 2.3 +/- 0.7 mm (P < .001). MRA resulted in a decrease in diameter stenosis of 20% or more in 44% of lesions, and the final diameter stenosis (after MRA alone or after PTCA) was less than 50% in 75% of lesions. Considering the small diameter of available burrs, the magnitude of lumen enlargement was equal to 91% of the burr diameter, and only 9% of the burr diameter was "lost" due to elastic recoil or spasm. These angiographic results were obtained despite the presence of complex lesion morphology, including the presence of calcification in 17% of lesions and ostial location in 26% of lesions. Significant angiographic complications included abrupt closure (13 lesions, 11.2%), no reflow (8 lesions, 7%), severe coronary vasospasm (16 lesions, 13.8%), and guide wire fracture (3 lesions, 2.7%). There were no coronary artery perforations. Adjunctive therapy, including salvage PTCA, thrombolytic agents, and vasodilators, was successful in treating angiographic complications in 42 of 49 lesions (86%). Clinical complications included Q-wave myocardial infarction (5 patients, 4.8%), non-Q-wave myocardial infarction (3 patients, 2.9%), femoral vascular injury requiring surgery (3 patients, 2.9%) or blood transfusion (8 patients, 7.7%), abrupt closure requiring emergency bypass graft surgery (2 patients, 1.9%), and in-hospital death (1 patient, 1.0%). Angiographic follow-up (mean follow-up interval, 5.0 +/- 2.0 months) was available in 84% of successfully treated patients and revealed a restenosis rate of 51%, defined as a residual diameter stenosis of more than 50%. There was no significant difference in restenosis rates between de novo lesions (50%) and restenosis (54%) lesions. CONCLUSIONS: These data suggest that for the treatment of most coronary stenoses, PTCA is required after MRA to achieve satisfactory lumen enlargement or to salvage complications. Angiographic complications appear to be more common after MRA, and salvage PTCA often is required to manage these device-induced complications. The combination of MRA and PTCA does not prevent restenosis.