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Background Burkholderia pseudomallei causes melioidosis, a serious illness that can be fatal if untreated or misdiagnosed. Culture from clinical specimens remains the gold standard but has low diagnostic sensitivity. Method In this study, we developed a rapid, sensitive and specific insulated isothermal Polymerase Chain Reaction (iiPCR) targeting bimA gene (Burkholderia Intracellular Motility A; BPSS1492) for the identification of B. pseudomallei. A pair of novel primers: BimA(F) and BimA(R) together with a probe were designed and 121 clinical B. pseudomallei strains obtained from numerous clinical sources and 10 ATCC non-targeted strains were tested with iiPCR and qPCR in parallel. Results All 121 B. pseudomallei isolates were positive for qPCR while 118 isolates were positive for iiPCR, demonstrating satisfactory agreement (97.71%; 95% CI [93.45–99.53%]; k = 0.87). Sensitivity of the bimA iiPCR/POCKIT assay was 97.52% with the lower detection limit of 14 ng/µL of B. pseudomallei DNA. The developed iiPCR assay did not cross-react with 10 types of non-targeted strains, indicating good specificity. Conclusion This bimA iiPCR/POCKIT assay will undoubtedly complement other methodologies used in the clinical laboratory for the rapid identification of this pathogen.

Background Left internal mammary artery (LIMA) grafting to the left anterior descending artery (LAD) is the most crucial step in any surgical coronary revascularization. It has been proved that using LIMA during coronary artery bypass grafting (CABG) resulted in better long term results in comparison to other conduits. With accumulation of data about failure and lower patency rates of vein grafts, the concept of total arterial revascularization (TAR) and multiple arterial revascularization (MAR) has developed to offer more physiological and durable conduits for CABG patients. Methods This study was conducted in the D epartment of C ardiothoracic S urgery, Sohag University Hospital, Egypt, between January 2012 and January 2017. 104 patients who underwent CABG during the initial experience were involved. They were divided into 2 groups, group A (MAR) 46 patients, and Group B (Conventional CABG) 58 patients. Demographic data, p reoperative risk factors, operative and post operative details were compared. Results With almost comparable preoperative demographic distribution and risk factors, results were comparable regarding post operative MI, incidence of deep sternal wound infection, number of distal anastomoses, postoperative bleeding, and the need for blood transfusion. Cross clamp time and total bypass time were slightly longer in group A than in group B with statistically significant difference. Conclusions Using multiple arterial grafts did not add a significant risk or time to the classic CABG. With accumulating evidence about better patency rate in arterial grafts, MAR is recommended especially in younger patients undergoing CABG.

These strains have heightened pathogenic potential for rapid dissemination to multiple tissues, including the central nervous system., Neurologic melioidosis is a serious, potentially fatal form of Burkholderia pseudomallei infection. Recently, we reported that a subset of clinical isolates of B. pseudomallei from Australia have heightened virulence and potential for dissemination to the central nervous system. In this study, we demonstrate that this subset has a B. mallei–like sequence variation of the actin-based motility gene, bimA. Compared with B. pseudomallei isolates having typical bimA alleles, isolates that contain the B. mallei–like variation demonstrate increased persistence in phagocytic cells and increased virulence with rapid systemic dissemination and replication within multiple tissues, including the brain and spinal cord, in an experimental model. These findings highlight the implications of bimA variation on disease progression of B. pseudomallei infection and have considerable clinical and public health implications with respect to the degree of neurotropic threat posed to human health.

Intracellular actin-based motility of the melioidosis pathogen Burkholderia pseudomallei requires the bacterial factor BimA. Located at one pole of the bacterium, BimA recruits and polymerizes cellular actin to promote bacterial motility within and between cells. Here, we describe an affinity approach coupled with mass spectrometry to identify cellular proteins recruited to BimA-expressing bacteria under conditions that promote actin polymerization. We identified a group of cellular proteins that are recruited to the B. pseudomallei surface in a BimA-dependent manner, a subset of which were independently validated with specific antisera including the ubiquitous scaffold protein Ras GTPase-activating-like protein (IQGAP1). IQGAP1 integrates several key cellular signaling pathways including those involved in actin dynamics and has been shown to be involved in the adhesion of attaching and effacing Escherichia coli to infected cells and invasion of host cells by Salmonella enterica serovar Typhimurium. Although a direct interaction between BimA and IQGAP1 could not be detected using either conventional pulldown or yeast two hybrid techniques, confocal microscopy revealed that IQGAP1 is recruited to B. pseudomallei actin tails in infected cells, and siRNA-mediated knockdown highlighted a role for this protein in controlling the length and actin density of B. pseudomallei actin tails.