Rationale: Uncontrolled inflammatory innate response and impaired adaptive immune response are associated with clinical severity in patients with Coronavirus disease 2019 (COVID-19).

Objectives: To compare the immunopathology of COVID-19 acute respiratory distress syndrome (ARDS) to that of non-COVID-19 ARDS, and to identify biomarkers associated with mortality in patients with COVID-19 ARDS.

Methods: Prospective observational monocenter study. Immunocompetent patients diagnosed with RT-PCR-confirmed SARS-CoV-2 infection and ARDS admitted between March 8 and March 30, 2020 were included and compared with patients with non-COVID-19 ARDS. The primary clinical endpoint of the study was mortality at day 28. Flow cytometry analyses and serum cytokines measurements were performed at days 1-2 and 4-6 of ICU admission.

Measurements and main results: As compared with patients with non-COVID-19 ARDS (n=36), those with COVID-19 (n=38) were not significantly different regarding age, gender, and SOFA and SAPS II scores but exhibited a higher day-28 mortality (34% vs 11%, p=0.030). COVID-19 patients showed profound and sustained T CD4+ (p=0.002), CD8+ (p<0.0001) and B (p<0.0001) lymphopenia, higher HLA-DR expression on monocytes (p<0.001) and higher serum concentrations of EGF, GM-CSF, IL-10, CCL2/MCP-1, CCL3/MIP-1a, CXCL10/IP-10, CCL5/RANTES, and CCL20/MIP-3a. After adjusting on age and SOFA, serum CXCL10/IP-10 (p=0.047) and GM-CSF (p=0.050) were higher and naso-pharyngeal RT-PCR cycle threshold values lower (p=0.010) in COVID-19 patients who were dead at day-28.

Conclusions: Profound global lymphopenia and a "chemokine signature" were observed in COVID-19 ARDS. Increased serum concentrations of CXCL10/IP-10 and GM-CSF, together with higher naso-pharyngeal SARS-CoV-2 viral load, were associated with day-28 mortality. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Keywords: SARS-CoV-2, COVID-19, ARDS, chemokines, cytokines.

The northern state of Amazonas is among the regions in Brazil most heavily affected by the COVID-19 epidemic and has experienced two exponentially growing waves, in early and late 2020. Through a genomic epidemiology study based on 250 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes from different Amazonas municipalities sampled between March 2020 and January 2021, we reveal that the first exponential growth phase was driven mostly by the dissemination of lineage B.1.195, which was gradually replaced by lineage B.1.1.28 between May and June 2020. The second wave coincides with the emergence of the variant of concern (VOC) P.1, which evolved from a local B.1.1.28 clade in late November 2020 and replaced the parental lineage in <2 months. Our findings support the conclusion that successive lineage replacements in Amazonas were driven by a complex combination of variable levels of social distancing measures and the emergence of a more transmissible VOC P.1 virus. These data provide insights to understanding the mechanisms underlying the COVID-19 epidemic waves and the risk of dissemination of SARS-CoV-2 VOC P.1 in Brazil and, potentially, worldwide.

<A<em>b</em>stractText>To examine the cross-sectional associations <em>b</em>etween regional tau, <em>β</em>-amyloid (A<em>β</em>), and cortical thickness and neuropsychological function across the preclinical and clinical spectrum of Alzheimer disease (AD).</A<em>b</em>stractText><p><div>(<em>b</em>)METHODS</<em>b</em>)</div>We included 106 participants from the Swedish Biomarkers for Identifying Neurodegenerative Disorders Early and Relia<em>b</em>ly (BioFINDER) study, of whom 33 had preclinical AD (A<em>β</em>-positive cognitively normal individuals), 25 had prodromal AD (A<em>β</em>-positive mild cognitive impairment), and 48 had pro<em>b</em>a<em>b</em>le AD dementia. All underwent [¹⁸F]flortaucipir (tau) and structural MRI (cortical thickness), and 88 of 106 underwent [¹⁸F]flutemetamol (A<em>β</em>) PET. Linear regression models adjusted for age, sex, and education were performed to examine associations <em>b</em>etween 7 regions of interest and 7 neuropsychological tests for all 3 imaging modalities.</p><p><div>(<em>b</em>)RESULTS</<em>b</em>)</div>In preclinical AD, [¹⁸F]flortaucipir, <em>b</em>ut not [¹⁸F]flutemetamol or cortical thickness, was associated with decreased glo<em>b</em>al cognition, memory, and processing speed (range standardized <em>β</em> = 0.35-0.52, <i>p</i> &<em>lt</em>; 0.05 uncorrected for mu<em>lt</em>iple comparisons). In the com<em>b</em>ined prodromal AD and AD dementia group, <em>b</em>oth increased [¹⁸F]flortaucipir uptake and reduced cortical thickness were associated with worse performance on a variety of neuropsychological tests (most regions of interest survived correction for mu<em>lt</em>iple comparisons at <i>p</i> &<em>lt</em>; 0.05), while increased [¹⁸F]flutemetamol uptake was specifically associated with lower scores on a delayed recall memory task (<i>p</i> &<em>lt</em>; 0.05 uncorrected for mu<em>lt</em>iple comparisons). The strongest effects for <em>b</em>oth [¹⁸F]flortaucipir and cortical thickness on cognition were found in the lateral and medial parietal cortex and lateral temporal cortex. The effect of [¹⁸F]flutemetamol on cognition was generally weaker and less region specific.</p><p><div>(<em>b</em>)CONCLUSION</<em>b</em>)</div>Our findings suggest that tau PET is more sensitive than A<em>β</em> PET and measures of cortical thickness for detecting early cognitive changes in preclinical AD. Furthermore, <em>b</em>oth [¹⁸F]flortaucipir PET and cortical thickness show strong cognitive correlates at the clinical stages of AD.</p>

<A<em>b</em>stractText>To identify predictors of pulmonary fi<em>b</em>rosis development <em>b</em>y com<em>b</em>ining follow-up thin-section CT findings and clinical features in patients discharged after treatment for COVID-19.</A<em>b</em>stractText><A<em>b</em>stractText>This retrospective study involved 32 confirmed COVID-19 patients who were divided into two groups according to the evidence of fi<em>b</em>rosis on their latest follow-up CT imaging. Clinical data and CT imaging features of all the patients in different stages were collected and analyzed for comparison.</A<em>b</em>stractText><p><div>(<em>b</em>)RESULTS</<em>b</em>)</div>The latest follow-up CT imaging showed fi<em>b</em>rosis in 14 patients (male, 12; female, 2) and no fi<em>b</em>rosis in 18 patients (male, 10; female, 8). Compared with the non-fi<em>b</em>rosis group, the fi<em>b</em>rosis group was older (median age: 54.0 years vs. 37.0 years, <i>p</i> = 0.008), and the median levels of C-reactive protein (53.4 mg/L vs. 10.0 mg/L, <i>p</i> = 0.002) and interleukin-6 (79.7 pg/L vs. 11.2 pg/L, <i>p</i> = 0.04) were also higher. The fi<em>b</em>rosis group had a longer-term of hospitalization (19.5 days vs. 10.0 days, <i>p</i> = 0.001), pulsed steroid therapy (11.0 days vs. 5.0 days, <i>p</i> &<em>lt</em>; 0.001), and antiviral therapy (12.0 days vs. 6.5 days, <i>p</i> = 0.012). More patients on the worst-state CT scan had an irregular interface (59.4% vs. 34.4%, <i>p</i> = 0.045) and a parenchymal <em>b</em>and (71.9% vs. 28.1%, <i>p</i> &<em>lt</em>; 0.001). On initial CT imaging, the irregular interface (57.1%) and parenchymal <em>b</em>and (50.0%) were more common in the fi<em>b</em>rosis group. On the worst-state CT imaging, interstitial thickening (78.6%), air <em>b</em>ronchogram (57.1%), irregular interface (85.7%), coarse reticular pattern (28.6%), parenchymal <em>b</em>and (92.9%), and pleural effusion (42.9%) were more common in the fi<em>b</em>rosis group.</p><A<em>b</em>stractText>Fi<em>b</em>rosis was more likely to develop in patients with severe clinical conditions, especially in patients with high inflammatory indicators. Interstitial thickening, irregular interface, coarse reticular pattern, and parenchymal <em>b</em>and manifested in the process of the disease may <em>b</em>e predictors of pulmonary fi<em>b</em>rosis. Irregular interface and parenchymal <em>b</em>and could predict the formation of pulmonary fi<em>b</em>rosis early.</A<em>b</em>stractText>

The progeny of mice treated with lymphotoxin (LT)-beta receptor (LTbetaR) and Ig (LTbetaR-Ig) lack Peyer's patches but not mesenteric lymph nodes (MLN). In this study, we used this approach to determine the importance of Peyer's patches for induction of mucosal IgA Ab responses in the murine gastrointestinal tract. Immunohistochemical analysis revealed that LTbetaR-Ig-treated, Peyer's patch null (PP null) mice possessed significant numbers of IgA-positive (IgA+) plasma cells in the intestinal lamina propria. Further, oral immunization of PP null mice with OVA plus cholera toxin as mucosal adjuvant resulted in Ag-specific mucosal IgA and serum IgG Ab responses. OVA-specific CD4+ T cells of the Th2 type were induced in MLN and spleen of PP null mice. In contrast, when TNF and LT-alpha double knockout (TNF/LT-alpha-/-) mice, which lack both Peyer's patches and MLN, were orally immunized with OVA plus cholera toxin, neither mucosal IgA nor serum IgG anti-OVA Abs were induced. On the other hand, LTbetaR-Ig- and TNF receptor 55-Ig-treated normal adult mice elicited OVA- and cholera toxin B subunit-specific mucosal IgA responses, indicating that both LT-alphabeta and TNF/LT-alpha pathways do not contribute for class switching for IgA Ab responses. These results show that the MLN plays a more important role than had been appreciated until now for the induction of both mucosal and systemic Ab responses after oral immunization. Further, organized Peyer's patches are not a strict requirement for induction of mucosal IgA Ab responses in the gastrointestinal tract.

We determined the complete nucleotide sequence of the toxB gene (375 base pairs in length), which encodes the B subunit of heat-labile enterotoxin produced from Escherichia coli pathogenic for humans (hLT). The amino acid sequence of the B subunit of hLT was deduced from the nucleotide sequence. Consequently, it has become possible to study the homology between the B subunits of three similar toxins: hLT, LT produced from E. coli pathogenic for piglets (pLT), and cholera toxin (the latter two sequences have been reported by others). The three B subunits are all 103 amino acids in length. A comparison of the toxB gene and the eltB gene, which encodes the B subunit of pLT, showed a 98% homology at the nucleotide level and a 95% homology at the amino acid (of a precursor) level, indicating the possibility that the two genes share a common ancestor. With respect to the B-subunit sequences, the homologies between hLT and pLT, between hLT and cholera toxin, and between pLT and cholera toxin were 96, 81, and 79%, respectively. Several large common sequences are conserved by the three peptides. In contrast, no sequences are present in both pLT and cholera toxin but missing in hLT.

As a result of failed induction of T cell tolerance to pancreatic B cells, non-obese diabetic (NOD) mice develop spontaneous autoimmune insulin-dependent diabetes mellitus (IDDM). The thymic stroma, which plays a crucial role in thymic T cell maturation, undergoes extensive premature disorganization in NOD mice, so it is of interest to examine NOD T cell development. In this study, both major and minor developmental populations of thymocytes of NOD/Lt mice were studied and compared to those of BALB/c, C57BL/6 and CBA mice by multiparameter flow cytometry (FACS). These results are described in detail and reveal that most thymocyte subsets were normally represented, including alphaTcR-CD4-CD8- (triple negative; TN), alphabetaTcR-CD4+CD8- and alphabetaTcR-CD4-CD8+ (immature single positive; ISP), alphabetaTcR-/lowCD4+CD8+ (double positive; DP) and alphabetaTcR+CD4+CD8- and alphabetaTcR+CD4-CD8+ (mature single positive; SP) as well as gammadelta T cells. However, NOD mice exhibited a marked deficiency of thymic alphabetaTcR+CD4-CD8- (alphabeta+DN) T cells. alphabeta+DN T cells, which are included among NK1+ T cells in C57BL/6 mice, produce large amounts of IL-4 on primary stimulation. Given the potential significance of NKT cells in immunoregulation, it is possible that the scarcity of these cells in NOD mice plays a role in the pathogenesis of IDDM.

Lymphotoxin-alpha-deficient (LT-alpha-/-) mice manifest congenital absence of lymph nodes (LNs) and Peyer's patches and disturbed spleen follicle structure. The splenic white pulp areas show loss of discrete T and B lymphocyte zones, of follicular dendritic cell (FDC) clusters, and of germinal centers (GCs). Tumor necrosis factor receptor I-deficient (TNFR-I-/-) mice show similar absence of FDC clusters and GCs but retain segregation of T and B cell zones. Rarely are mesenteric LNs found in LT-alpha-/- mice. These mesenteric LNs show segregation of T and B cell zones similar to wild-type mice. In contrast, mesenteric LNs in TNFR-I-/- mice manifest grossly disturbed organization of T and B cells. Both LT-alpha-/- and TNFR-I-/- mice lacked FDC clusters in LNs and spleen. Interestingly, although both LT-alpha-/- and TNFR-I-/- mice that had been immunized with sheep red blood cells failed to form GCs in the spleen, they both developed GC-like clusters of peanut agglutinin-positive (PNA+) cells in their LNs. Furthermore, when lethally irradiated recombination activating gene (RAG)-1-deficient (RAG-1(-/-)) mice that had received spleen cells from LT-alpha-/- mice were immunized with sheep red blood cells, they failed to generate PNA+ clusters in the reconstituted spleen but showed robust PNA+ clusters in the reconstituted LNs. These data demonstrate that the signals that regulate the development of distinct T and B cell zones as well as the signals that regulate B cell activation to produce clusters of PNA+ cells differ between the spleen and LNs.

The lymphotoxin (LT) beta receptor plays a critical role in secondary lymphoid organogenesis and the classical and alternative NF-kappaB pathways have been implicated in this process. IKKalpha is a key molecule for the activation of the alternative NF-kappaB pathway. However, its precise role and target genes in secondary lymphoid organogenesis remain unknown, particularly with regard to high endothelial venules (HEV). In this study, we show that IKKalpha(AA) mutant mice, who lack inducible kinase activity, have hypocellular lymph nodes (LN) and nasal-associated lymphoid (NALT) tissue characterized by marked defects in microarchitecture and HEV. In addition, IKKalpha(AA) LNs showed reduced lymphoid chemokine CCL19, CCL21, and CXCL13 expression. IKKalpha(AA) LN- and NALT-HEV were abnormal in appearance with reduced expression of peripheral node addressin (PNAd) explained by a severe reduction in the HEV-associated proteins, glycosylation-dependent cell adhesion molecule 1 (GlyCAM-1), and high endothelial cell sulfotransferase, a PNAd-generating enzyme that is a target of LTalphabeta. In this study, analysis of LTbeta(-/-) mice identifies GlyCAM-1 as another LTbeta-dependent gene. In contrast, TNFRI(-/-) mice, which lose classical NF-kappaB pathway activity but retain alternative NF-kappaB pathway activity, showed relatively normal GlyCAM-1 and HEC-6ST expression in LN-HEV. In addition, in this communication, it is demonstrated that LTbetaR is prominently expressed on LN- and NALT-HEV. Thus, these data reveal a critical role for IKKalpha in LN and NALT development, identify GlyCAM-1 and high endothelial cell sulfotransferase as new IKKalpha-dependent target genes, and suggest that LTbetaR signaling on HEV can regulate HEV-specific gene expression.

Two bacterial products that have been demonstrated to function as mucosal adjuvants are cholera toxin (CT), produced by various strains of Vibrio cholerae, and the heat-labile enterotoxin (LT) produced by some enterotoxigenic strains of Escherichia coli. Although LT and CT have many features in common, they are clearly distinct molecules with biochemical and immunologic differences which make them unique. The goal of this study was to determine the basis for these biological differences by constructing and characterizing chimeric CT-LT molecules. Toxin gene fragments were subcloned to create two constructs, each expressing the enzymatically active A subunit of one toxin and the receptor binding B subunit of the other toxin. These hybrid toxins were purified, and the composition and assembly of CT A subunit (CT-A)-LT B subunit (LT-B) and LT A subunit (LT-A)-CT B subunit (CT-B) were confirmed. Hybrids were evaluated for enzymatic activity, as measured by the accumulation of cyclic AMP in Caco-2 cells, and the enterotoxicity of each toxin was assessed in a patent-mouse assay. The results demonstrated that LT-A-CT-B induces the accumulation of lower levels of cyclic AMP and has less enterotoxicity than either wild-type toxin or the other hybrid. Nonetheless, this hybrid retains adjuvant activity equivalent to or greater than that of either wild-type toxin or the other hybrid when used in conjunction with tetanus toxoid for intranasal immunization of BALB/c mice. Importantly, the ability of LT to induce a type 1 cytokine response was found to be a function of LT-A. Specifically, LT-A-CT-B was able to augment the levels of antigen-specific gamma interferon (IFN-gamma) and interleukin 5 to levels comparable to those achieved with native LT, while CT-A-LT-B and native CT both produced lower levels of antigen-specific IFN-gamma. Thus, these toxin hybrids possess unique biological characteristics and provide information about the basis for differences in the biological activities observed for CT and LT.

Human mesenchymal stem cells (MSC) strongly repress activated T-cell proliferation through the production of a complex set of soluble factors, including the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO), which is induced by IFN-gamma. Conversely, MSCs support survival of follicular lymphoma (FL) B cells, in particular after exposure to tumor necrosis factor-alpha (TNF) and lymphotoxin-alpha1beta2 (LT). The role of MSCs on normal and malignant B-cell growth in steady-state and inflammatory conditions remains to be fully explored. We show here that resting MSCs sustain activated normal B-cell proliferation and survival, whereas IFN-gamma-conditioned MSCs mediate IDO-dependent B-cell growth arrest and apoptosis. IFN-gamma, TNF, and LT are significantly overexpressed by the microenvironment of invaded FL-lymph nodes, but their relative expression patterns are highly heterogeneous between samples. In vitro, IFN-gamma abrogates the B-cell supportive phenotype induced by TNF and LT on MSCs. Moreover, IFN-gamma overrules the growth promoting effect of MSCs on primary purified FL B cells. Altogether, these results underline the crucial role of the cytokine context in the local crosstalk between malignant cells and their microenvironment and provide new insights into our knowledge of the FL cell niche that emerges as a new promising target for innovative therapeutic strategies.

METHODS

Between 1988-1997, the total number of liver transplantations performed in the US more than doubled from 1,713-4,158, and the number of centers performing liver transplantations increased from 59-107. In recent years, the yearly net gain in the number of operating centers has slowed, and the differences in LT volume across centers has remained stable.

RESULTS

During the first year following transplantation, patient survival was approximately the same for adults and children, while retransplantation-free survival was poorest among children. Thereafter, survival declined more rapidly among adults than among children.

UNASSIGNED

The estimated cumulative probability of a pediatric recipient surviving for 10 years following transplantation was .80, and surviving for 10 years without retransplantation was .59. In general, few deaths or retransplantations were observed more than 4 years after the initial transplantation. Factors independently associated with patient and retransplantation-free survival among children were year of transplantation, recipient age, being on life support while awaiting transplantation, primary liver disease, serum creatinine, total bilirubin, donor age, donor race, and warm ischemic time. Recipient race, a multi-organ transplant procedure, and serum albumin level were significantly associated with patient survival only. The use of a reduced-size or split liver for transplantation in children was independently associated with retransplantation-free survival, but not with patient survival.

UNASSIGNED

The estimated cumulative probability of an adult recipient surviving for 10 years following transplantation was .61, and surviving for 10 years without retransplantation was .46 with the median retransplantation-free survival time estimated at 9.2 years. Factors independently associated with patient and retransplantation-free survival among adults were year of transplantation, recipient age, recipient race, recipient location awaiting transplantation, primary liver disease, serum creatinine and albumin levels, hepatitis B surface antigen status, donor age, donor anti-CMV status, warm ischemic time, sex match, pretransplant ventilator or inotrope use, and recipient anti-HCV status. Pre-transplant bilirubin level, a multi-organ transplant procedure, and the finding of an incidental tumor were significantly associated with patient survival; and donor race, ABO match, and uncontrolled variceal bleeding were associated with retransplantation-free survival.

Human placentae and two of the cell types in placentae (cytotrophoblasts and macrophages) were examined by RT-PCR for transcripts of the eight TNF superfamily ligands known to induce death of activated immune cells, tumour cells, and virus-infected cells (TNFalpha, LT alpha, LT beta, FasL, TRAIL, TWEAK, LIGHT, 4-1BBL). Transcripts for all ligands were detected in term placenta but LT alpha and 4-1BBL were not detected in first trimester placenta. Although term cytotrophoblasts contained mRNAs specific for TNF alpha, LT alpha, TWEAK, and 4-1BBL, messages encoding LT beta, FasL, TRAIL, and LIGHT were absent. In term placental macrophages, messages for all ligands except 4-1BBL were present. Transcripts for the 14 receptors to which the ligands bind, six of which contain death-domains (TNFR1, Fas, DR3, DR4, DR5, DR6), were also identified using RT-PCR. Term and first trimester placentae contained transcripts for all receptors except 4-1BB. Although term cytotrophoblasts lacked receptor mRNA encoding 4-1BB and OPG, term placental macrophages lacked DcR1 and OPG. Detection of nearly all the death-inducing TNF superfamily ligands and their receptors in human placentae implies that these powerful cytokines contribute to programmed or activated cell death in this organ.

Although the combination of lamivudine (LAM) and high-dose intravenous (IV) hepatitis B immunoglobulin (HBIG) is very effective in preventing hepatitis B virus (HBV) recurrence after liver transplantation (LT), the major limitation of this regimen is its high cost. A more cost-effective, convenient and widely accepted regimen is urgently needed. We evaluated the safety and efficacy of another strategy using LAM and individualized low-dose intramuscular (IM) HBIG. Between May 2002 and December 2009, a total of 254 adult patients undergoing LT for HBV-related benign end-stage liver diseases received this regimen in our center. The mean follow-up of these patients was 41.2 +/- 22.7 months. Their 1-, 3- and 5-year survival rates were 85.3%, 77.4% and 76.4%, respectively, and 1-, 3- and 5-year HBV recurrence rates were 2.3%, 6.2% and 8.2%. Fourteen patients experienced posttransplant HBV recurrence. Pretransplant high viral load and posttransplant prednisone withdrawal time were observed to be associated with recurrence. In conclusion, combination therapy with LAM and individualized low-dose IM HBIG provides a safe and effective prophylaxis against HBV recurrence after LT at about 5% of the cost of conventional high-dose IV HBIG regimens.

BACKGROUND

Recent evidence suggests that bone marrow lesions (BMLs) play a pivotal role in knee osteoarthritis (OA). The aims of this study were to determine: 1) whether baseline BML presence and/or severity predict site-specific cartilage defect progression and cartilage volume loss; and 2) whether baseline cartilage defects predict site-specific BML progression.

METHODS

A total of 405 subjects (mean age 63 years, range 52 to 79) were measured at baseline and approximately 2.7 years later. Magnetic resonance imaging (MRI) of the right knee was performed to measure knee cartilage volume, cartilage defects (0 to 4), and BMLs (0 to 3) at the medial tibial (MT), medial femoral (MF), lateral tibial (LT), and lateral femoral (LF) sites. Logistic regression and generalized estimating equations were used to examine the relationship between BMLs and cartilage defects and cartilage volume loss.

RESULTS

At all four sites, baseline BML presence predicted defect progression (odds ratio (OR) 2.4 to 6.4, all P < 0.05), and cartilage volume loss (-0.9 to -2.9% difference per annum, all P < 0.05) at the same site. In multivariable analysis, there was a significant relationship between BML severity and defect progression at all four sites (OR 1.8 to 3.2, all P < 0.05) and BML severity and cartilage volume loss at the MF, LT, and LF sites (β -22.1 to -42.0, all P < 0.05). Additionally, baseline defect severity predicted BML progression at the MT and LF sites (OR 3.3 to 3.7, all P < 0.01). Lastly, there was a greater increase in cartilage volume loss at the MT and LT sites when both larger defects and BMLs were present at baseline (all P < 0.05).

CONCLUSIONS

Baseline BMLs predicted site-specific defect progression and cartilage volume loss in a dose-response manner suggesting BMLs may have a local effect on cartilage homeostasis. Baseline defects predicted site-specific BML progression, which may represent increased bone loading adjacent to defects. These results suggest BMLs and defects are interconnected and play key roles in knee cartilage volume loss; thus, both should be considered targets for intervention.

(<em>b</em>)Rationale</<em>b</em>): Chest computed tomography (CT) has <em>b</em>een used for the coronavirus disease 2019 (COVID-19) monitoring. However, the imaging risk factors for poor clinical outcomes remain unclear. In this study, we aimed to assess the imaging characteristics and risk factors associated with adverse composite endpoints in patients with COVID-19 pneumonia. (<em>b</em>)Methods</<em>b</em>): This retrospective cohort study enrolled patients with la<em>b</em>oratory-confirmed COVID-19 from 24 designated hospitals in Jiangsu province, China, <em>b</em>etween 10 January and 18 Fe<em>b</em>ruary 2020. Clinical and initial CT findings at admission were extracted from medical records. Patients aged &<em>lt</em>; 18 years or without availa<em>b</em>le clinical or CT records were excluded. The composite endpoints were admission to ICU, acute respiratory failure occurrence, or shock during hospitalization. The volume, density, and location of lesions, including ground-glass opacity (GGO) and consolidation, were quantitatively analyzed in each patient. Mu<em>lt</em>ivaria<em>b</em>le logistic regression models were used to identify the risk factors among age and CT parameters associated with the composite endpoints. (<em>b</em>)Resu<em>lt</em>s</<em>b</em>): In this study, 625 la<em>b</em>oratory-confirmed COVID-19 patients were enrolled; among them, 179 patients without an initial CT at admission and 25 patients aged &<em>lt</em>; 18 years old were excluded and 421 patients were included in analysis. The median age was 48.0 years and the male proportion was 53% (224/421). During the follow-up period, 64 (15%) patients had a composite endpoint. There was an association of older age (odds ratio [OR], 1.04; 95% confidence interval [CI]: 1.01-1.06; <i>P</i> = 0.003), larger consolidation lesions in the upper lung (Right: OR, 1.13; 95%CI: 1.03-1.25, <i>P</i> =0.01; Left: OR,1.15; 95%CI: 1.01-1.32; <i>P</i> = 0.04) with increased odds of adverse endpoints. (<em>b</em>)Conclusion</<em>b</em>): There was an association of older age and larger consolidation in upper lungs on admission with higher odds of poor outcomes in patients with COVID-19.

We utilized clostridial toxins (with known specificities for inhibition of GTPases) to ascertain the contribution of candidate GTPases in physiologic insulin secretion from beta cells. Exposure of normal rat islets or isolated beta (HIT-T15) cells to Clostridium difficile toxins A and B catalyzed the glucosylation (and thereby the inactivation) of Rac, Cdc42, and Rho endogenous to beta cells; concomitantly, either toxin reduced glucose- or potassium-induced insulin secretion from rat islets and HIT cells. Treatment of beta cells with Clostridium sordellii lethal toxin (LT; which modified only Ras, Rap, and Rac) also reduced glucose- or potassium-induced secretion. However, clostridial toxin C3-exoenzyme (which ADP-ribosylates and inactivates only Rho) was without any effect on either glucose- or potassium-induced insulin secretion. These data suggest that Cdc42, Rac, Ras, and/or Rap (but not Rho) may be needed for glucose- or potassium-mediated secretion. The effects of these toxins appear to be specific on stimulus-secretion coupling, since no difference in metabolic viability (assessed colorimetrically by quantitating the conversion of the tetrazolium salt into a formazan in a reduction reaction driven by nutrient metabolism) was demonstrable between control and toxin (A or LT)-treated beta cells. Toxin (A or LT) treatment also did not alter glucose- or potassium-mediated rises in cytosolic free calcium concentrations ([Ca2+]i), suggesting that these GTPases are involved in steps distal to elevations in [Ca2+]i. Recent findings indicate that the carboxyl methylation of Cdc42 is stimulated by only glucose, whereas that of Rap (Kowluru et al., J Clin Invest 98: 540-555, 1996) and Rac (present study) are regulated by glucose or potassium. Together, these findings provide direct evidence, for the first time, that the Rho subfamily of GTPases plays a key regulatory role(s) in insulin secretion, and they suggest that Cdc42 may be required for early steps in glucose stimulation of insulin release, whereas Rap and/or Rac may be required for a later step(s) in the stimulus-secretion coupling cascade (i.e. Ca2+-induced exocytosis of insulin).

The B subunit of Escherichia coli heat labile enterotoxin (LT-B) is a potent oral immunogen with potential for use as a vaccine, a carrier molecule to deliver antigens to gut-associated lymphoid tissues, and possibly an adjuvant to make coadministered vaccines more effective. LT-B produced in plants was shown to be functional and immunogenic in animals and humans. In this work, we show that maize-derived LT-B is strongly associated with starch granules in endosperm. Using immunogold labeling/electron microscopy, cell fractionation, and protein analysis techniques, we observed that LT-B protein could be detected both internally and externally in starch granules. This strong association confers an effective copurification of the antigen with the starch fraction of maize kernels, thermostability desirable in maize processing, and resistance to peptic degradation in simulated gastric fluid digests, an important attribute for an orally delivered antigen.

The burnout syndrome is characterized by emotional exhaustion, depersonalization, and reduced personal achievement. Uncertainty exists about the prevalence of burnout among medical and surgical residents. Associations between burnout and gender, age, specialty, and geographical location of training are unclear. In this meta-analysis, we aimed to quantitatively summarize the global prevalence rates of burnout among residents, by specialty and its contributing factors. We searched PubMed, PsycINFO, Embase, and Web of Science to identify studies that examined the prevalence of burnout among residents from various specialties and countries. The primary outcome assessed was the aggregate prevalence of burnout among all residents. The random effects model was used to calculate the aggregate prevalence, and heterogeneity was assessed by I² statistic and Cochran's Q statistic. We also performed meta-regression and subgroup analysis. The aggregate prevalence of burnout was 51.0% (95% CI: 45.0-57.0%, I² = 97%) in 22,778 residents. Meta-regression found that the mean age (β = 0.34, 95% CI: 0.28-0.40, p &lt; 0.001) and the proportion of males (β = 0.4, 95% CI = 0.10-0.69, p = 0.009) were significant moderators. Subgroup analysis by specialty showed that radiology (77.16%, 95% CI: 5.99-99.45), neurology (71.93%, 95% CI: 65.78-77.39), and general surgery (58.39%, 95% CI: 45.72-70.04) were the top three specialties with the highest prevalence of burnout. In contrast, psychiatry (42.05%, 95% CI: 33.09-51.58), oncology (38.36%, 95% CI: 32.69-44.37), and family medicine (35.97%, 95% CI: 13.89-66.18) had the lowest prevalence of burnout. Subgroup analysis also found that the prevalence of burnout in several Asian countries was 57.18% (95% CI: 45.8-67.85); in several European countries it was 27.72% (95% CI: 17.4-41.11) and in North America it was 51.64% (46.96-56.28). Our findings suggest a high prevalence of burnout among medical and surgical residents. Older and male residents suffered more than their respective counterparts.

Purpose: Acalabrutinib, a highly selective, potent, Bruton tyrosine kinase inhibitor, was evaluated in this global, multicenter, randomized, open-label, phase III study in patients with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL).

Methods: Eligible patients, aged ≥ 18 years with R/R CLL, were randomly assigned 1:1 centrally and stratified by del(17p) status, Eastern Cooperative Oncology Group performance status score, and number of prior lines of therapy. Patients received acalabrutinib monotherapy or investigator's choice (idelalisib plus rituximab [I-R] or bendamustine plus rituximab [B-R]). The primary end point was progression-free survival (PFS) assessed by an independent review committee (IRC) in the intent-to-treat population. Key secondary end points included IRC-assessed overall response rate, overall survival, and safety.

Results: From February 21, 2017, to January 17, 2018, a total of 398 patients were assessed for eligibility; 310 patients were randomly assigned to acalabrutinib monotherapy (n = 155) or investigator's choice (n = 155; I-R, n = 119; B-R, n = 36). Patients had received a median of two prior therapies (range, 1-10). After a median follow-up of 16.1 months (range, 0.03-22.4 months), median PFS was significantly longer with acalabrutinib monotherapy (PFS not reached) compared with investigator's choice (16.5 months [95% CI, 14.0 to 17.1 months]; hazard ratio, 0.31 [95% CI, 0.20 to 0.49]; P < .0001). Estimated 12-month PFS was 88% (95% CI, 81% to 92%) for acalabrutinib and 68% (95% CI, 59% to 75%) for investigator's choice. Serious adverse events occurred in 29% of patients (n = 44 of 154) treated with acalabrutinib monotherapy, 56% (n = 66 of 118) with I-R, and 26% (n = 9 of 35) with B-R. Deaths occurred in 10% (n = 15 of 154), 11% (n = 13 of 118), and 14% (n = 5 of 35) of patients receiving acalabrutinib monotherapy, I-R, and B-R, respectively.

Conclusion: Acalabrutinib significantly improved PFS compared with I-R or B-R and has an acceptable safety profile in patients with R/R CLL.

Introduction: Existing socioeconomic and racial disparities in healthcare access in New York City have likely impacted the public health response to COVID-19. An ecological study was performed to determine the spatial distribution of COVID-19 testing by ZIP code Tabulation Area and investigate if testing was associated with race or SES.

Methods: Data were obtained from the New York City coronavirus data repository and 2018 American Community Survey 5-year estimates. A combined index of SES was created using principal component analysis and incorporated household income, gross rent, poverty, education, working class status, unemployment, and occupants per room. Multivariable Poisson regressions were performed to predict the number of total tests and the ratio of positive tests to total tests performed, using the SES index, racial composition, and Hispanic composition as predictors.

Results: The number of total tests significantly increased with the increasing proportion of white residents (β=0.004, SE=0.001, p=0.0032) but not with increasing Hispanic composition or SES index score. The ratio of positive tests to total tests significantly decreased with the increasing proportion of white residents in the ZIP code Tabulation Area (β= -0.003, SE=0.000 6, p&lt;0.001) and with increasing SES index score (β= -0.001 6, SE=0.0007, p=0.0159).

Conclusions: In New York City, COVID-19 testing has not been proportional to need; existing socioeconomic and racial disparities in healthcare access have likely impacted public health response. There is urgent need for widespread testing and public health outreach for the most vulnerable communities in New York City.

Objective: Diabetes may unfavorably influence the outcome of coronavirus disease 19 (COVID-19), but the determinants of this effect are still poorly understood. In this monocentric study, we aimed at evaluating the impact of type 2 diabetes, comorbidities, plasma glucose levels, and antidiabetes medications on the survival of COVID-19 patients.

Research design and methods: This was a case series involving 387 COVID-19 patients admitted to a single center in the region of Lombardy, the epicenter of the severe acute respiratory syndrome coronavirus 2 pandemic in Italy, between 20 February and 9 April 2020. Medical history, pharmacological treatments, laboratory findings, and clinical outcomes of patients without diabetes and patients with type 2 diabetes were compared. Cox proportional hazards analysis was applied to investigate risk factors associated with mortality.

Results: Our samples included 90 patients (23.3%) with type 2 diabetes, who displayed double the mortality rate of subjects without diabetes (42.3% vs. 21.7%, P &lt; 0.001). In spite of this, after correction for age and sex, risk of mortality was significantly associated with a history of hypertension (adjusted hazard ratio [aHR] 1.84, 95% CI 1.15-2.95; P = 0.011), coronary artery disease (aHR 1.56, 95% CI 1.04-2.35; P = 0.031), chronic kidney disease (aHR 2.07, 95% CI 1.27-3.38; P = 0.003), stroke (aHR 2.09, 95% CI 1.23-3.55; P = 0.006), and cancer (aHR 1.57, 95% CI 1.08-2.42; P = 0.04) but not with type 2 diabetes (P = 0.170). In patients with diabetes, elevated plasma glucose (aHR 1.22, 95% CI 1.04-1.44, per mmol/L; P = 0.015) and IL-6 levels at admission (aHR 2.47, 95% CI 1.28-4.78, per 1-SD increase; P = 0.007) as well as treatments with insulin (aHR 3.05, 95% CI 1.57-5.95; P = 0.001) and β-blockers (aHR 3.20, 95% CI 1.50-6.60; P = 0.001) were independently associated with increased mortality, whereas the use of dipeptidyl peptidase 4 inhibitors was significantly and independently associated with a lower risk of mortality (aHR 0.13, 95% CI 0.02-0.92; P = 0.042).

Conclusions: Plasma glucose levels at admission and antidiabetes drugs may influence the survival of COVID-19 patients affected by type 2 diabetes.