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PurposeWe reviewed the clinical experience of kidney transplant recipients diagnosed with severe acute respiratory syndrome coronavirus 2 infection in order to understand the impact of the current coronavirus disease 2019 (COVID-19) pandemic infection on transplant recipients. Given that early reports from heavily affected areas demonstrated a very high mortality rate amongst kidney transplant recipients, ranging between 30% and 40%, we sought to evaluate outcomes at a center with a high burden of cases but not experiencing acute crisis due to COVID-19.ProceduresIn this single center retrospective observational study, medical records of all kidney transplant recipients at the UCLA Medical Center were reviewed for a diagnosis of COVID-19 by polymerase chain reaction, followed by chart review to determine kidney transplant characteristics and clinical course.Main findingsA total of 41 kidney transplant recipients were identified with COVID-19 positive polymerase chain reaction. Recipients had been transplanted for a median of 47 months before diagnosis. The large proportion of infected individuals were minorities (Hispanic 65.9%, black 14.6%), on prednisone, tacrolimus, and mycophenolate mofetil (95.1%, 87.8%, and 87.8%, respectively), and had excellent allograft function (median 1.25 mg/dL). The most common presenting symptoms were fever, dyspnea, or cough. Most patients were hospitalized (63.4%); mortality was 9.8% and occurred only in patients in the intensive care unit. The most common treatment was reduction or removal of antimetabolite (77.8%). Approximately 26.9% presented with AKI.ConclusionsCOVID-19 infection in kidney transplant recipients results in a higher rate of hospitalization and mortality than in the general population. In an area with a high number of infections, the mortality rate was lower compared with earlier reports from areas experiencing early surge and strain on the medical system. Minorities were disproportionately affected. Future studies are needed to determine optimal approach to treatment and management of immunosuppression in kidney transplant recipients with COVID-19 infection.

BackgroundBK virus infection remains an important cause of loss of allograft function after kidney transplantation. We sought to determine whether polyfunctional T cells secreting multiple cytokines simultaneously, which have been shown to be associated with viral control, could be detected early after start of BK viremia, which would provide insight into the mechanism of successful antiviral control.MethodsPeripheral blood mononuclear cells collected during episodes of BK viral replication were evaluated by multiparameter flow cytometry after stimulation by overlapping peptide pools of BK virus antigen to determine frequency of CD8+ and CD4+ T cells expressing 1 or more cytokines simultaneously, as well as markers of T-cell activation, exhaustion, and maturation.ResultsBK virus controllers, defined as those with episodes of BK viremia of 3 months or less, had an 11-fold increase in frequency of CD8+ polyfunctional T cells expressing multiple cytokines, as compared with patients with prolonged episodes of BK viremia. Patients with only low level BK viremia expressed low frequencies of polyfunctional T cells. Polyfunctional T cells were predominantly of the effector memory maturation subtype and expressed the cytotoxicity marker CD107a.ConclusionsNoninvasive techniques for immune assessment of peripheral blood can provide insight into the mechanism of control of BK virus replication and may allow for future patient risk stratification and customization of immune suppression at the onset of BK viremia.

Interferon-gamma release assays have limited sensitivity for detecting latent tuberculosis infection. In this study, we determine if the addition of immunomodulators to the QuantiFERON-TB Gold In-Tube (QFT-GIT) increased test sensitivity without compromising specificity. We prospectively compared QFT-GIT results with and without incubation with 2 immunomodulators (lipopolysaccharide [LPS] and polyinosine-polycytidylic acid [PolyIC]) in 2 cohorts-113 culture-confirmed tuberculosis (TB) subjects in Hanoi, Vietnam, and 226 documented QFT-GIT-negative, low TB risk health care workers undergoing annual TB screening at a US academic institution. Sensitivity of the tests in TB subjects was 84.1% with the standard QFT-GIT and 85.8% and 74.3% after incubation with LPS and PolyIC, respectively. Specificity in low TB risk health care workers was 100% with the standard QFT-GIT by design and 86.7% with LPS and 63.3% with PolyIC. In conclusion, use of the 2 immunomodulators did not improve sensitivity of the QFT-GIT in TB patients and reduced specificity in low-risk health care workers.

This research paper focuses on examining the relationship between the cash conversion cycle (CCC) and the profitability of Food and Beverage (F&B) companies in Vietnam by utilizing quantitative models. Analyzing a sample of 23 companies in the period from 2015 to 2021, the study revealsthat a reduction in the CCC positively influences profitability, as measured by the return on assets (ROA) ratio. The study further dissects the impact of CCC’s components, including days payable outstanding (DPO), days inventory outstanding (DIO), and days sales outstanding (DSO), on profitability. Based on regression analysis results, the study recommends that companies under study endeavor to reduce the durations of DPO, DIO, DSO, and CCC to improve profitability. Implementing strategies to tighten credit policies and optimize capital utilization is suggested as a means to achieve this objective.

The manganese-promoted cobalt supported on gamma alumina was prepared following the incipient wetness impregnation method and employed as a catalyst for carbon dioxide reforming of methane. The addition of manganese has changed the physicochemical properties of the original material. The Co3O4 crystallite size was decreased from 12.14 to 8.66 nm, suggesting a higher metal dispersion. The activation of the catalyst precursor was more effective with less energy required. Notably, the carbon dioxide adsorption over the catalyst surface was greatly enhanced in the presence of 1 wt% manganese. Taken all together, the manganese-promoted catalyst showed an outperformance with higher activity and stability in comparison with the pristine. At 973 K, 1 atm, CH4/CO2 ratio of 1, the addition of 1 wt% Mn into 5Co/Al2O3 led to notable increases in CH4 (15.2%) and CO2 (17.68%) conversions. Also, the stability of Mn-promoted was much higher compared to pristine catalyst with only 0.3 wt% of undesirable coke formed. Meanwhile, it was 4.94 wt% in the case of 5Co/Al2O3 at the same operating condition. Furthermore, the role of carbon dioxide adsorption in carbon dioxide reforming of methane was investigated. At a proper combination of carbon dioxide activation and methane dissociation, the catalytic activity can be significantly enhanced with much lower activation energies for the feedstock gases. Nevertheless, when the adsorption of carbon dioxide was dominant, catalytic activity was much lower and the deactivation occurred rapidly. [ABSTRACT FROM AUTHOR]

The dnaX36(TS) mutant of Escherichia coli confers a distinct mutator phenotype characterized by enhancement of transversion base substitutions and certain (-1) frameshift mutations. Here, we have further investigated the possible mechanism(s) underlying this mutator effect, focusing in particular on the role of the various E. coli DNA polymerases. The dnaX gene encodes the x subunit of DNA polymerase III (Pol III) holoenzyme, the enzyme responsible for replication of the bacterial chromosome. The dnaX36 defect resides in the C-terminal domain V of [tau], essential for interaction of x with the a (polymerase) subunit, suggesting that the mutator phenotype is caused by an impaired or altered [alpha]-[tau] interaction. We previously proposed that the mutator activity results from aberrant processing of terminal mismatches created by Pol III insertion errors. The present results, including lack of interaction of dnaX36 with mutM, mutY, and recA defects, support our assumption that dnaX36-mediated mutations originate as errors of replication rather than DNA damagerelated events. Second, an important role is described for DNA Pol II and Pol IV in preventing and producing, respectively, the mutations. In the system used, a high fraction of the mutations is dependent on the action of Pol IV in a (dinB) gene dosage-dependent manner. However, an even larger but opposing role is deduced for Pol II, revealing Pol II to be a major editor of Pol III mediated replication errors. Overall, the results provide insight into the interplay of the various DNA polymerases, and of [tau] subunit, in securing a high fidelity of replication.

Research was conducted to examine the physiological role and the mechanism involved in the effects of amino acids on protein metabolism, target of rapamycin (TOR) activation and other events such as the multicellular clustering of adipocytes. The individual amino acids responsible for these effects were identified by focusing on the TOR substrate and translational repressor 4E-BP1. Results indicate that the mechanism used by amino acids to stimulate phosphorylation involved the interaction of leucine with a specific binding site.

Amorphous molybdenum sulfide (MoSx) is a promising alternative to Pt catalyst for the H2 evolution in water. However, it is suffered of an electrochemical corrosion. In this report, we present a strategy to tack this issue by embedding the MoSx catalyst within a porous poly(3,4‐ethylenedioxythiophene) (PEDOT) matrix. The PEDOT host is firstly grown onto a fluorine‐doped tin oxide (FTO) electrode by electrochemical polymerization of EDOT monomer in an acetonitrile solution to perform a porous structure. The MoSx catalyst is subsequently deposited onto the PEDOT by an electrochemical oxidation of [MoS4]2− monomer. In a 0.5 M H2SO4 electrolyte solution, the MoSx/PEDOT shows higher H2‐evolving catalytic activities (current density of 34.2 mA/cm2 at −0.4 V vs RHE) in comparison to a pristine MoSx grown on a planar FTO electrode having similar catalyst loading (24.2 mA/cm2). The PEDOT matrix contributes to enhance the stability of MoSx catalyst by a significant manner. As such, the MoSx/PEDOT retains 81 % of its best catalytic activity after 1000 potential scans from 0 to −0.4 V vs. RHE, whereas a planar MoSx catalyst is completely degraded after about 240 potential scans, due to its complete corrosion. [ABSTRACT FROM AUTHOR]

Hiện nay, ngành sản xuất các sản phẩm may mặc đóng góp một phần không nhỏ vào kim ngạch xuất khẩu Việt Nam. Tuy nhiên, phần lớn các công đoạn sản xuất ở nước ta hiện nay đều được thực hiện thủ công. Để nâng cao chất lượng và sản lượng các sản phẩm may mặc, việc tự động hóa các quy trình sản xuất là vấn đề cấp thiết. Bài báo này giới thiệu một thiết kế của hệ thống máy cắt vải tự động. Máy được thiết kế bao gồm một bàn máy ba bậc tự do và một hệ thống dao cắt rung, được dẫn động bởi hệ thống các động cơ AC servo. Một mô hình thực nghiệm được xây dựng để kiểm tra hệ thống bàn máy được thiết kế. Trong các hệ thống cắt vải, việc bố trí các mảnh cần cắt lên trên một tấm vật liệu để giảm thiểu vật liệu hao phí, được gọi là bài toán giác sơ đồ, là một vấn đề rất đáng được quan tâm. Trong nghiên cứu nay, hệ thống máy cắt vải sử dụng công cụ mã nguồn mở Deepnest, dựa trên thuật toán No Fit Polygon và giải thuật di truyền được, để xây dựng sơ đồ cắt tối ưu cho hệ thống. Kết quả nghiên cứu cho thấy thiết kế máy cắt vải được đề xuất trong bài báo này có thể đạt được hiệu năng cao với chi phí đầu tư thấp.

ABSTRACT: To evaluate the association between the single nucleotide polymorphism (SNP) rs227493 in the MEOX2 gene and nonsyndromic cleft palate only, this research was conducted as a case–control study by comparing a nonsyndromic cleft palate only group with an independent, healthy, and unaffected control group who were both examined by specialists. Based on clinical examination and medical records, we analyzed a total of 570 DNA samples, including 277 cases and 293 controls, which were extracted from dry blood spot samples collected from both the Odonto and Maxillofacial Hospital in Ho Chi Minh City and Nguyen Dinh Chieu Hospital in Ben Tre province, respectively. The standard procedures of genotyping the specific SNP (rs2237493) for MEOX2 were performed on a StepOne Realtime PCR system with TaqMan SNP Genotyping Assays. Significant statistical differences were observed in allelic frequencies (allele T and allele G) between the non‐syndromic cleft palate only and control groups in female subjects, with an allelic odds ratio of 1.455 (95% confidence interval: 1.026–2.064) and P < 0.05. These study findings suggest that nonsyndromic isolated cleft palate might be influenced by variation of MEOX2, especially SNP rs2237493 in Vietnamese females. [ABSTRACT FROM AUTHOR]

Introduction: Activated factor X (FXa) plays a central role in the coagulation cascade, whereas accumulating evidence illustrates that it mediates the development of vascular dysfunction through the activation of protease-activated receptor 2 (PAR2). We hypothesis that rivaroxaban (Riv), a direct FXa inhibitor, attenuates endothelial dysfunction in diabetic mice. Methods and results: Diabetes was induced by a single intraperitoneal injection of streptozotocin (STZ, 180mg/kg) to eight-week-old wild-type (WT) mice. Diabetic mice were fed a normal chow containing Riv (5 mg/kg/day) after STZ injection for 3 weeks. Mice fed non-supplemented chow served as the control. Induction of diabetes increased PAR2 expression in the aorta (P<0.05). Vascular reactivity assay showed that Riv administration attenuated endothelial dysfunction as determined by acetylcholine-dependent vasodilation compared with the control (P<0.001) without the alteration of blood glucose level. Western blot analysis demonstrated that Riv treatment promoted the phosphorylation of eNOSser1177 in the abdominal aorta compared with the control (P<0.001). We also induced diabetes to PAR2-deficient (PAR2-/-) mice by STZ injection. Induction of diabetes in PAR2-/- mice did not impair endothelial function and eNOSser1177 phosphorylation compared with non-diabetic group. Ex-vivo studies using aortic rings obtained from WT mice showed that FXa or PAR2 agonist significantly impaired endothelial function, however, aortic rings obtained from PAR2-/- mice did not show this response. In addition, endothelial dysfunction induced by FXa was ameliorated in presence of a JNK inhibitor, SP600125. In vitro studies using human umbilical vein endothelial cells (HUVEC) demonstrated that FXa promoted the phosphorylation of JNK and reduced the phosphorylation of eNOSser1177 (P<0.001 and P<0.05, respectively). SP600125 ameliorated impairment of eNOSser1177 phosphorylation induced by FXa in HUVEC (P<0.001). Conclusions: Rivaroxaban attenuates the development of endothelial dysfunction by the inhibition of the PAR2/JNK signaling pathway in diabetic mice. FXa-PAR2 signaling might be a potential therapeutic target for diabetes-induced endothelial dysfunction. [ABSTRACT FROM AUTHOR]

Xã hội hiện đại đòi hỏi con người phải có khả năng học tập một cách thường xuyên, liên tục, suốt đời. Mà cốt lõi của nó là khả năng tự học, tự phấn đấu của mỗi người nhằm nâng cao trình độ chuyên môn, nghiệp vụ, nâng cao chất lượng sống của bản thân. Đào tạo từ xa là một trong các phương thức có khả năng thỏa mãn những đòi hỏi này. Để xây dựng thành công xã hội học tập, phương thức đào tạo từ xa đã và đang được Đảng và Nhà nước ta quan tâm, phát triển, mở rộng. Điều đó được tiếp tục khẳng định tại Đại hội Đại biểu toàn quốc lần thứ XI Đảng Cộng sản ViệtNam: ?Đẩy mạnh phong trào khuyến học, khuyến tài, xây dựng xã hội học tập, mở rộng các phương thức đào tạo từ xa?? [1]. Đào tạo từ xa ở Trường Đại học Cần Thơ (ĐHCT) ra đời góp phần thực hiện chủ trương, đường lối phát triển giáo dục-đào tạo của Đảng và Nhà nước ở khu vực đồng bằng sông Cửu Long (ĐBSCL). Bài viết xin giới thiệu đôi nét về công tác đào tạo từ xa ở Trường ĐHCT, về một số khó khăn trong công tác này đồng thời đề xuất kiến nghị nhằm góp phần nâng cao chất lượng đào tạo từ xa của Trường ĐHCT nói riêng và cả nước nói chung.