A nationwide survey was carried out in Korea to assess the prevalence of Shigella strains producing extended-spectrum beta-lactamases (ESBLs). From 1991 to 2002, 5,911 clinical strains were isolated and screened for resistance to extended-spectrum cephalosporins. Twenty of the Shigella isolates were ESBL positive, based on the synergistic effects between clavulanate and selected beta-lactams (c...

OBJECTIVES To investigate the diversity of plasmids that carry bla(TEM-52) genes among Escherichia coli and Salmonella enterica originating from animals, meat products and humans. METHODS A collection of 22 bla(TEM-52)-encoding plasmids was characterized by restriction fragment length polymorphism (RFLP), replicon typing (by PCR or replicon sequencing), susceptibility testing, assessment of p...

Based on the sample type, TEM imaging can be classified into cross-sectional TEM (XTEM) and planeview TEM (PTEM). The advantage of XTEM is that it shows stacked layer structures that reflect the manufacturing process steps. Plane-view TEM, on the other hand, is suitable for cases where either the exact defect location has not been isolated for XTEM or the anomaly has affected structures more la...

PURPOSE After total mesorectal excision (TME) for rectal cancer, pathology is standardized with margin status as a predictor for recurrence. This has yet to be implemented after transanal endoscopic microsurgery (TEM) and was investigated prospectively for T1 rectal adenocarcinomas. PATIENTS AND METHODS Eighty patients after TEM were compared to 75 patients after TME. The study protocol inclu...

Transmission electron microscopy (TEM) is a powerful tool for the investigation of the microstructure of materials, providing crystallographic information and composition at the nanometer scale. For such studies, samples should be transparent to the electron beam. In this review, TEM sample preparation techniques for different classes of materials, such as metals and alloys, multilayered coatin...

Transanal endoscopic microsurgery may be considered medically necessary for treatment of clinical T1 rectal adenocarcinomas than cannot be removed using other means of local excision and that meet all of the following criteria:  Located in the middle or upper part of the rectum  Well or moderately differentiated (G1 or G2)  Without lymphadenopathy or microscopic angiolymphatic invasion  Les...

Widespread use of beta-lactam antibiotics has promoted the evolution of beta-lactamase mutant enzymes that can hydrolyze ever newer classes of these drugs. Among the most pernicious mutants are the inhibitor-resistant TEM beta-lactamases (IRTs), which elude mechanism-based inhibitors, such as clavulanate. Despite much research on these IRTs, little is known about the structural bases of their a...