Publications by authors named "David Cech"

d-Arabinose-5-phosphate (A5P) isomerases (APIs) catalyze the interconversion of d-ribulose-5-phosphate and d-arabinose-5-phosphate. Various Gram-negative bacteria, such as the uropathogenic strain CFT073, contain multiple API paralogs (KdsD, GutQ, KpsF, and c3406) that have been assigned various cellular functions. The d-arabinose-5-phosphate formed by these enzymes seems to play important roles in the biosynthesis of lipopolysaccharide (LPS) and group 2 K-antigen capsules, as well as in the regulation of the cellular d-glucitol uptake and uropathogenic infectivity/virulence.

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D-Arabinose 5-phosphate isomerases (APIs) catalyze the interconversion of D-ribulose 5-phosphate and D-arabinose 5-phosphate (A5P). A5P is an intermediate in the biosynthesis of 3-deoxy-D-manno-octulosonate (Kdo), an essential component of lipopolysaccharide, the lipopolysaccharide found in the outer membrane of Gram-negative bacteria. The genome of the Gram-positive pathogen Listeria monocytogenes contains a gene encoding a putative sugar isomerase domain API, Q723E8, with significant similarity to c3406, the only one of four APIs from Escherichia coli CFT073 that lacks a cystathionine-β-synthase domain.

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Arabinose-5-phosphate isomerases (APIs) catalyze the interconversion of d-ribulose-5-phosphate and D-arabinose-5-phosphate, the first step in the biosynthesis of 3-deoxy-D-manno-octulosonic acid (Kdo), an essential component of the lipopolysaccharide in Gram-negative bacteria. Classical APIs, such as Escherichia coli KdsD, contain a sugar isomerase domain and a tandem cystathionine beta-synthase domain. Despite substantial effort, little is known about structure-function relationships in these APIs.

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Percutaneous sacroplasty is a procedure adapted from vertebroplasty, which is designed to ameliorate the painful morbidity associated with sacral insufficiency fractures without the invasiveness of open surgery. Early estimates of efficacy, according to several case reports and small series, appear promising, but the procedure is not without risk. Several cases of radiculopathy due to nerve root compression by extravasated polymethylmethacrylate (PMMA) have been reported.

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A 64-year-old man with a history of traumatic brain injury 4 years previously presented with progressive cognitive decline and gait abnormality. MRI revealed diffusion restriction in the bilateral centrum semiovale and multiple serpiginous flow voids. Cerebral angiogram revealed a total of six intracranial dural arteriovenous fistulas with separate fistulas of the right and left sphenoid bones, left clival plexus, right transverse sinus, right sigmoid sinus, and superior sagittal sinus.

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A 64-year-old man with a history of traumatic brain injury 4 years previously presented with progressive cognitive decline and gait abnormality. MRI revealed diffusion restriction in the bilateral centrum semiovale and multiple serpiginous flow voids. Cerebral angiogram revealed a total of six intracranial dural arteriovenous fistulas with separate fistulas of the right and left sphenoid bones, left clival plexus, right transverse sinus, right sigmoid sinus, and superior sagittal sinus.

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