Search

Novel Coronavirus, COVID-19 discovered in December, 2019 in Wuhan, China started a world-wide epidemic. It is not clear till now what is the pathogenesis of this virus infection in human or the exact strategies of host immune response in combating this novel threat to human beings. However, morbidity and mortality of COVID-19 infections vary widely from asymptomatic, mild to deadly critical. Strangely, children were found to be protected from severe or deadly critical infections, while elderly and immunocompromised adults are most affected badly by this virus. It is necessary to disclose the possible viral and host interactions that lead to such variable morbid effects among patients of COVID-19 infections. [ABSTRACT FROM AUTHOR]

Introduction: There is a need for a reliable, time-saving, and specific detection assay for coliforms, environmental E. coli, and Enterobacteriaceae worldwide. Aim: To innovate a new principle of phage-based rapid diagnostic test for detecting E. coli bacteria in short time and low titer. Materials and Methods: A phage mixture of 200 E. coli specific phages, including 22 specific for Enterohaemorrhagic E.coli (EHEC), were used in a new detection platform, a phage-based Adenylate Kinase Bioluminescence Assay (AKBA). Ten EHEC E. coli and 30 universal E.coli isolates were used for AKBA assay. Results: AKBA showed positive detection of E.coli bacteria at 103 CFU in just 20 minutes. The phage-based detection was highly specific at strain level of E.coli. The sensitivity and specificity of AKBA was 74% and 78%, respectively. Conclusion: A rapid and strain-specific diagnostic test was prepared for E.coli by using coliphages. The significance and impact of the study shows that it might be feasible to formulate a phage-based assay against any Gram negative or positive bacteria using the same approaches of the current AKBA assay with slight modifications. [ABSTRACT FROM AUTHOR]

Streptococcus bovis (S. bovis) bacteria are associated with colorectal cancer and adenoma. S. bovis is currently named S. gallolyticus. 25 to 80% of patients with S. bovis/gallolyticus bacteremia have concomitant colorectal tumors. Colonic neoplasia may arise years after the presentation of bacteremia or infectious endocarditis of S. bovis/gallolyticus. The presence of S. bovis/gallolyticus bacteremia and/or endocarditis is also related to the presence of villous or tubular-villous adenomas in the large intestine. In addition, serological relationship of S. gallolyticus with colorectal tumors and direct colonization of S. gallolyticus in tissues of colorectal tumors were found. However, this association is still under controversy and has long been underestimated. Moreover, the etiological versus non-etiological nature of this association is not settled yet. Therefore, by covering the most of up to date studies, this review attempts to clarify the nature and the core of S. bovis/gallolyicus association with colorectal tumors and analyze the possible underlying mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Background: It was hypothesized that the observed slight immunostimulatory effect of the 23-valent pneumococcal polysaccharide (pneumo-23) vaccine might be due to the presence of low levels of zwitterionic motifs. Therefore, it was hypothesized further that introducing zwitterionic motifs experimentally into polysaccharides of pneumo-23 vaccine might render it an effective immunostimulatory agent. Objective: This study was conducted to assess the in vitro immunostimulatory effect of zwitterionized pneumo-23 (Z-P23) vaccine compared with the nonzwitterionized commercial pneumo-23 (C-P23) vaccine. Methods: In vitro proliferation, ELISA-based in vitro cytokine synthesis (interleukin [IL]-2, interferon [IFN]-γ, and IL-10), and immunofluorescence microscopy-based immune cell profiling (CD4+, CD8+, and CD21+ cells) assays were used to evaluate the immunostimulatory effect of Z-P23 on peripheral blood mononuclear cells (PBMC) of immunosuppressed cancer (IC) patients and healthy control subjects in comparison with PBMC exposed to C-P23, concanavalin A (positive control), and phosphate-buffered saline (PBS) (negative control). Results: Z-P23 induced proliferation of PBMC in the IC (81.1%) and control (75.1%) groups significantly higher than that achieved with concanavalin A in the IC group (51.0%; P = 0.01) but not in the control group (89.2%; P = NS). This was also significantly higher than that achieved with C-P23 in the IC (4.8%; P < 0.001) and control (6.2%; P < 0.001) groups. Z-P23 induced IL-2 and IFN-γ synthesis in the IC group (0.61 and 0.45 ng/mL, respectively) significantly more than that with C-P23 (0.4 and 0.45 ng/mL; P = 0.002 and P <0.001), concanavalin A (0.45 and 0.31 ng/mL; P = 0.021 and P = 0.03), and PBS (0.41 and 0.29 ng/mL; P = 0.005 and P = 0.04) but not the control group. Z-P23 induced expansion of CD4+, CD8+, and CD21+ lymphocytes (39.3%, 42.7%, and 8.1%, respectively) in the IC group higher than that with C-P23 (28.3%, 30.1%, and 5.5%; P = 0.01, P = 0.003, and P = NS), concanavalin A (27.2%, 35.8%, and 4.1%; P = 0.02, P = 0.048, and P = 0.035), and PBS (25.6%, 31.9%, and 4.2%; P = 0.018, P = 0.02, and P = 0.045). Conclusion: The in vitro immunostimulatory potential of Z-P23 was clearly observed on PBMC of IC patients as well as, to a lesser extent, healthy control subjects, stimulating the synthesis of core cytokines of T-helper 1, and primarily inducing CD4+ and CD8+T cells. [Copyright &y& Elsevier]

Background: Colorectal cancer (CRC) has long been associated with bacteremia and/or endocarditis by Streptococcus gallolyticus member bacteria (SGMB) but the direct colonization of SGMB along with its molecular carcinogenic role, if any, has not been investigated. We assessed the colonization of SGMB in CRC patients with history of bacteremia (CRC-w/bac) and without history of bacteremia (CRC-wo/bac) by isolating SGMB from feces, mucosal surfaces of colorectum, and colorectal tissues and detecting SGMB DNA, via PCR and in situ hybridization (ISH) assays targeting SodA gene in colorectal tissues. Moreover, mRNA of IL1, IL-8, COX-2, IFN-γ, c-Myc, and Bcl-2 in colorectal tissues of studied groups was assessed via ISH and RT-PCR. Results: SGMB were found to be remarkably isolated in tumorous (TU) and non-tumorous (NTU) tissues of CRCw/ bac, 20.5% and 17.3%, and CRC-wo/bac, 12.8% and 11.5%, respectively while only 2% of control tissues revealed SGMB (P < 0.05); such contrast was not found in mucosal and fecal isolation of SGMB. The positive detection of SGMB DNA in TU and NTU of CRC-w/bac and CRC-wo/bac via PCR, 48.7%, 35.9%, 32.7%, and 23%, respectively, and ISH, 46.1%, 30.7%, 28.8%, and 17.3%, respectively, was higher than in control tissues, 4 and 2%, respectively (P < 0.05). SGMB count measured via quantitative PCR of SGMB DNA in terms of copy number (CN), in TU and NTU of CRC-w/bac and CRC-wo/bac, 2.96-4.72, 1.29-2.81, 2.16-2.92, and 0.67-2.07 log10 CN/g respectively, showed higher colonization in TU than in NTU and in CRC-w/bac than in CRC-wo/bac (P < 0.05). The PCR-based mRNA ratio and ISH-based percentage of positively stained cells of IL-1, 1.77 and 70.3%, COX-2, 1.63 and 44.8%, and IL-8, 1.73 and 70.3%, respectively, rather than IFN-g, c-Myc, and Bcl-2, were higher in SGMB positive patients than in control or SGMB negative patients (P < 0.05). Conclusions: The current study indicated that colorectal cancer is remarkably associated with SGMB; moreover, molecular detection of SGMB in CRC was superior to link SGMB with CRC tumors highlighting a possible direct and active role of SGMB in CRC development through most probably inflammation-based sequel of tumor development or propagation via, but not limited to, IL-1, COX-2, and IL-8. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to comparatively elucidate the underlying molecular pathways and clinicopathological criteria in schistosomal bladder tumor (SBT) versus nonschistosomal bladder tumor (NSBT). Methods: This study explored the role of p53, p16, bcl-2, ki-67, c-myc, Rb and EGFR, by using Immunohistochemistry assay, in 45 SBT and 39 NSBT patients in comparison with 16 schistosomal chronic cystitis (SC), 28 non-schistosomal chronic cystitis (NSC), and 20 normal control (CTL) subjects. The studied markers in SBT and NSBT were correlated with different clinicopathological criteria namely, tumor histopathology, grading, invasiveness, stage, and presentation of the disease. Results: SBT was associated with high grade invasive squamous cell carcinoma (SCC) while NSBT was associated with lower grade less invasive transitional cell carcinoma (TCC). The expression of p53, bcl-2, c-myc, and EGFR was higher in SBT than in NSBT while Rb was higher in NSBT than in SBT. However, p16 and ki-67 were not different between SBT and NSBT. The profile of molecular markers in SC was similar to NSC except for EGFR which was higher in SC than in NSC. Both SC and NSC showed higher level of p53, bcl-2, ki-67, and EGFR than in CTL group while p16, Rb, and c-myc were not different. p53 was associated with high grade SCC in both SBT and NSBT. Bcl-2 was associated with high grade invasive tumors in SBT and NSBT. P16 was associated with low grade, late stage, and recurrent SBT and high grade, invasive, late stage, and recurrent NSBT. Rb was associated with SCC in SBT, invasive tumors in NSBT, and late stage and recurrent presentation in both SBT and NSBT. C-myc was associated with high grade, invasive, and late stage SBT and SCC, high grade, invasive, and late stage NSBT. EGFR was associated with invasive SCC in SBT and invasive, high grade, and late stage TCC in NSBT. ki-67 was associated with invasive SBT and high grade late stage NSBT. Conclusion: SBT and NSBT showed distinct molecular profile of tumor development and progression which can be taken into consideration in fine adjusting the anti-cancer therapy for SBT and NSBT. [ABSTRACT FROM AUTHOR]