Grafting of Anionic Decahydro-Closo-Decaborate Clusters on Keggin and Dawson-Type Polyoxometalates: Syntheses, Studies in Solution, DFT Calculations and Electrochemical Properties.

Herein we report the synthesis of a new class of compounds associating Keggin and Dawson-type Polyoxometalates (POMs) with a derivative of the anionic decahydro-closo-decaborate cluster [B10H10]2- through aminopropylsilyl ligand (APTES) acting as both a linker and a spacer between the two negatively charged species. Three new adducts were isolated and fully characterized by various NMR techniques and MALDI-TOF mass spectrometry, notably revealing the isolation of an unprecedented monofunctionalized SiW10 derivative stabilized through intramolecular H-H dihydrogen contacts. DFT as well as electrochemical studies allowed studying the electronic effect of grafting the decaborate cluster on the POM moiety and its consequences on the hydrogen evolution reaction (HER) properties.

Unprecedented coupling reaction between two anionic species of a closo-decahydrodecaborate cluster and an Anderson-type polyoxometalate.

A novel decahydrodecaborate-functionalized Anderson type polyoxometalate has been synthesized and characterized in solution by ESI-MS, various NMR techniques and electrochemical methods. DFT studies provide strong support to understand the properties of this hybrid system.

High-risk clones and novel sequence type ST4497 of Klebsiella pneumoniae clinical isolates producing different alleles of NDM-type and other carbapenemases from a single tertiary-care centre in Egypt.

Enterobacteria producing NDM carbapenemases represent a severe diagnostic and therapeutic challenge in healthcare settings. Infections caused by NDM-positive strains are usually associated with high mortality rates and very limited treatment options. A total number of 33 carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates were included in this study, comprising 30 recovered from clinical diagnostic samples and 3 cultured from screening rectal swabs taken at patient admission. Bacterial identification was performed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF/MS) and antibiotic susceptibility testing was performed by reference broth microdilution and a commercial automated method. Isolates were investigated for carbapenemase production using the ß-CARBA test, the modified carbapenem inactivation method (mCIM) and, for the 30 clinical isolates, by MALDI-TOF/MS, using the MBT STARⓇ-Carba IVD Kit. Carbapenem resistance genes were characterised by PCR and sequencing. Seven different blaNDM gene variants were identified in 94% of the isolates, whilst three variants of blaOXA-48-like were detected in 27% of the isolates. Most CRKP corresponded to high-risk clones (ST147, ST11 and ST15). Novel ST4497 is reported for the first time in this study as well as the first emergence of K. pneumoniae ST231 producing OXA-232 in Egypt. These results indicate an ongoing evolution of the blaNDM genes in our area and confirm the need for a maintained surveillance system in order to monitor the spread of these mobile blaNDM genes.

Herpes simplex virus type-2 in Egyptian patients with bladder cancer or cystitis.

The present study was designed to investigate the prevalence of herpes simplex virus type-2 (HSV-2) in Egyptian patients with bladder cancer or cystitis and to evaluate the performance of different diagnostic HSV-2 assays. The study included 50 patients: 27 with bladder cancer (group I), 23 with cystitis (group II) and 20 subjects as controls (group III). HSV-2 DNA was detected using polymerase chain reaction (PCR) on bladder tissue and buffy coat cells (BCC). Electron microscopic studies (EMS) on BCC and ELISAs for IgM, IgG and specific glycoprotein G-2 (gG-2) IgG were performed. HSV-2 DNA was detected by PCR on bladder tissue biopsies in 29.6% and 21.7% of group I and II respectively and it was also detected by PCR on BCC in 22.2% and 21.7% of group I and II respectively. EMS revealed HSV like particles in 16.6% of cases. IgG, specific gG-2 IgG and IgM were detected in 30%, 16% and 6% of cases respectively. The different assays were evaluated in relation to PCR on bladder tissue biopsies. The gG-2-based ELISA and EMS on BCC were found to be highly specific (97.3% and 100% respectively), with similar low sensitivity of approximately 54%. PCR on BCC was the most sensitive assay. The association of HSV-2 with bladder cancer is suggested especially in schistosomal patients.

Rapid identification of methicillin-resistant staphylococci bacteremia among intensive care unit patients.

Staphylococci represent the most commonly encountered blood culture isolates. With the spread of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) in hospitals, rapid and reliable methods for their detection are warranted in order to provide choice of appropriate antimicrobial therapy. This study evaluated 4 rapid methods directly from positive blood cultures in parallel with each other (on the same day) for identification of methicillin-resistant staphylococcal isolates, in addition to antimicrobial susceptibility testing (AST), to compare the workflow for each test and to reduce the turnaround time (TAT) in order to be presented as practical applications in our microbiology laboratory. A total of 56 bacteremic patients' blood cultures with Gram stains showing gram-positive cocci (GPC) in clusters were included. The following direct assays were evaluated: direct tube coagulase (DTC) test, analytical profile index (API)-Staph kit for species identification coupled with antimicrobial susceptibility testing (AST), latex agglutination for detection of PBP2a (PBP2a LA Assay), and cefoxitin disk diffusion assay. The direct results were compared with results obtained with isolated colonies using standard methods as well as detection of the mecA gene by PCR. DTC and API-staph exhibited sensitivities of 96% and 96.8% and specificity of 100% for direct identification of staphylococcal isolates. Both PBP2a LA and cefoxitin DD assays exhibited sensitivity of 100% for detection of both MRSA and MRCoNS and specificities of 100% and 75% (PBP2a assay) and 90% and 100% (cefoxitin DD) for identification of methicillin-sensitive isolates, respectively. For direct antimicrobial susceptibility testing (DAST), the overall error rate was 1.11%. In conclusion, direct identification and susceptibility testing by any of these assays yielded acceptable performance and timely results - 24 hours earlier than routine subculture - and can be easily incorporated into routine processing of positive blood cultures to improve the outcomes for the patient and the costs to hospitals. Therefore, it is recommended to use the method with high sensitivity and the shortest TAT.

Role of human papillomavirus types 16, 18, and 52 in recurrent cystitis and urinary bladder cancer among Egyptian patients.

BACKGROUND: Bladder cancer is a common malignancy in Egypt. Human papillomavirus (HPV) could have a possible etiologic role in bladder carcinogenesis. We aimed to estimate the prevalence of HPV-16, -18, and -52 in Egyptian patients with bladder cancer or recurrent cystitis, and to study the correlation of type-specific HPV-immunoglobulin (Ig)G with polymerase chain reaction (PCR) results and different clinicopathologic parameters. METHODS: This study was conducted on 60 inpatients of the Urosurgery Department at the Theodor Bilharz Research Institute (TBRI), who were identified histopathologically and clinically as cancer bladder (group I, 20 patients), cystitis (group II, 24 patients), and cancer bladder with cystitis (group III, 16 patients), and a fourth group of 20 healthy control subjects (for serologic testing). Patients were subjected to detection of HPV-16 and -18 DNA by PCR on bladder tissue biopsies (BTB) and buffy coat cells (BCC) and serum IgG antibodies to L1 capsids of HPV-16 and -52 IgG by enzyme-linked immunosorbent assay (ELISA). RESULTS: HPV-16 and -18 DNA were detected in BTB (30% and 10%, respectively) with significantly higher rates (44.4%) in bladder cancer than cystitis cases (11.11%), with significant association with schistosomal affection (78.6% and 25%, respectively) and recurrence (48%, HPV-16). There was a significant association of transitional cell carcinoma (TCC) with HPV-16 in 69.2% and 61.1% of BCC and BTB, respectively. Multiple HPV types 16, 18, and 52 were significantly higher than single types (79.2% and 20.8%, respectively). The observed absolute association between seropositivity of HPV-52 (11.7%) and HPV-16 (26.7%) was significantly associated with TCC in patient groups only. CONCLUSION: Our study confirmed the significant association of HPV-16, -18 and -52 with bladder cancer in Egyptian patients, with the suggestion of viral synergistic action in bladder carcinogenesis. Such HPV types were significantly associated with TCC tumors of low grade and high stage, with schistosomal affection and recurrence tendency. HPV serology would pave the way for better management and follow-up of patients and for optimal design and evaluation of HPV vaccination.

SEN virus infection in Egyptian patients with chronic hepatitis C and patients undergoing hemodialysis.

The SEN virus has been tentatively linked to transfusion-associated non-A to E hepatitis. The aim of the present study was to 1) determine the prevalence of SEN virus among Egyptian patients with hepatitis C virus (HCV)-related chronic liver disease and patients undergoing hemodialysis and 2) demonstrate the clinical effect of SEN virus infection on coexistent hepatitis C in terms of severity and probability of developing hepatocellular carcinoma. Polymerase chain reaction was used to detect SEN virus-D and SEN virus-H DNA in serum samples of 74 patients with HCV-related chronic liver disease, 45 uremic patients undergoing maintenance hemodialysis, and 28 healthy controls. SEN virus-D/H DNA was detected in 13.5% of patients with chronic liver disease, 11.1% of patients undergoing hemodialysis, and 7.1% of healthy controls, with no significant differences between patients and the control group. Clinical and biochemical measures did not significantly differ between SEN virus-infected and noninfected patients in the chronic liver disease group or the hemodialysis group. The rate of SEN virus infection was significantly higher in patients with chronic liver disease and hepatocellular carcinoma (33.3%) than in those with chronic liver disease only (8.5%) (P < .05). In conclusion, SEN virus does not seem to be a common infection in Egyptian patients. It has no apparent influence on the severity of coexistent HCV-related chronic liver disease but could be a risk factor for hepatocellular carcinoma in such patients. Further studies are needed to define the etiopathogenic role of SEN virus infection in the development of hepatocellular carcinoma.