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T Gonzalez

Publications and source records attributed to T Gonzalez.

29 records · Page 2Linked to original sources
PubMed1988

Identification and characterization of starvation-regulated genetic loci in Salmonella typhimurium by using Mu d-directed lacZ operon fusions.

We used the technique of Mu d-directed lac operon fusion formation in an effort to identify loci in Salmonella typhimurium which are transcriptionally regulated by nutrient starvation conditions. We identified lacZ operon fusions in eight genetic loci, all of which exhibited increased transcription when starved for two or more of the following nutrients: nicotinate, phosphate, ammonium, glucose, and sulfate. The loci have been designated stiA to stiH for starvation-inducible loci. Mutations in two sti loci (stiC and stiD) significantly decreased cell viability during prolonged periods of nicotinate starvation, stiA and stiD are linked and map at 30 min. The stiC, stiE, stiG, and stiH loci mapped at approximately 77, 43, 88, and 56 min, respectively, on the S. typhimurium linkage map.

Ammonia↗
PubMed1986

Global control in Salmonella typhimurium: two-dimensional electrophoretic analysis of starvation-, anaerobiosis-, and heat shock-inducible proteins.

The response of Salmonella typhimurium to various forms of environmental stress was examined by using O'Farrell two-dimensional gel electrophoresis. Polypeptides (a total of 110) which quantitatively increased during various starvations, anaerobiosis, or heat shock were identified and cataloged in reference to a standard polypeptide map. Although significant overlap was noted during comparison of proteins induced by different starvations, only a few proteins produced during heat shock or anaerobiosis were also identified as starvation inducible.

Anaerobiosis↗
PubMedDate not supplied

Library preparation of derivatives of 1,4,10,13-tetraoxa-7,16-diaza-cycloctadecane and their fluorescence behavior for signaling purposes.

In the present work, we report the library preparation on solid supports of 20 derivatives of 1,4,10,13-tetraoxa-7,15-diaza-cycloctadecane 1(a-e)(w,x,y,z) carrying a fluorescent dansyl group. The sensing fluorescence behavior of these materials toward alkali and alkali earth metal ions was studied by packing the beads into a conventional flow-through cell in a FIA (flow injection analysis) approach. The fluorescence emission of these materials' responses shows a fluorescence increase to Li+, Na+, K+, NH4+, Ca2+, and Mg2+ with maximum sensitivity for Mg2+ over the rest of the ions. The analytical potential of these materials is outlined, and the sensing response mechanism, based on a photoinduced electron-transfer process, is proposed.

Alkanes↗
PubMedDate not supplied

Erosive azotemic osteoarthropathy of the hands in chronic ambulatory peritoneal dialysis and hemodialysis.

OBJECTIVE: We studied the prevalence and significance of erosive azotemic osteoarthropathy (EAO) and its relationship with other osteoarticular abnormalities of dialysis-associated arthropathy (DAA). METHODS: 112 patients undergoing maintenance dialysis were studied: 63 hemodialysis (HD) and 49 continuous ambulatory peritoneal dialysis (CAPD). X-ray of the hands, shoulders, pelvis and cervical spine were examined for destructive spondyloarthropathy (SDA), bone cysts (BC), EAO and subperiosteal resorption. Beta 2-microglobulin (beta 2-m) and PTH were also measured. RESULTS: Fifteen patients (13%) had EAO, usually in several joints of the hands, DIPs being the most frequently affected. Both patients on HD and those on CAPD had EAO, although the prevalence was higher in the HD group, 12 (19%) vs. 3 (6%). Patients with EAO were older (p < 0.05) and had more carpal tunnel syndrome (CTS) (p < 0.05) and BC (p < 0.01). Only 3 out of 15 patients with EAO had severe secondary hyperparathyroidism (sHPTH) (PTH > 500), while 9/15 had neither radiologic nor laboratory evidence of sHPTH. No differences were found regarding the duration of dialysis, or beta 2-m or PTH level. CONCLUSION: EAO is not related to sHPTH and should be included within the spectrum of the clinical manifestations of DAA. Due to its location and radiologic picture, it is possible that etiologic factors leading to primary osteoarthritis may play a role in the development and evolution of EAO.

Adult↗