Isolation of a genetic locus associated with metronidazole resistance in Helicobacter pylori

We examined the molecular mechanism of metronidazole resistance by constructing a lambda-Zap II phagemid expression library with genomic DNA from a metronidazole-resistance strain of Helicobacter pylori. Twenty-two clones were found to have elevated MTZ resistances in XLOLR strain of E. coli. Phagemids belonging to the twenty two clones were extracted and then retransformed into the XLOLR strain of E. coli. After MTZ selection, five clones could confer metronidazole resistance consistently. According to Southern hybridization and DNA sequencing, the five clones contained a same locus, recA. In addition, transforming the five clones into BL21 strain of E. coli produced a higher resistance to MTZ. Interestingly, electroporation of one of the five phagemid clones into two MTZ sensitive H. pylori yielded MTZ resistant strains. Comparing amino acid sequence in MTZ resistant with sensitive isolates revealed two point mutations at this locus. Above results suggest that mutation in recA may be associated with metronidazole resistance of H. pylori.     

Menadione-induced oxidative stress accelerates onset of Emory mouse cataract in vivo

This article takes issue with procedural reductionism, which is the inclination to reduce all matters of judgement and responsibility to the following of some procedure or rule. Two scenarios provide content for a discussion of professional discretion in the context of accountability. The author shows that in professional life there will always be situations that stand beyond the rules of procedures and require the unique judgement of the professional at the time. While this judgement may be determined by the facts available in a situation of uncertainty, it cannot be reduced to the facts (including facts about rules and procedures). The moral judgement will still have an essential indeterminancy about it.     

Serial cytological assay of micronucleus induction: a new tool to predict human cancer radiosensitivity

The role of the propeptide sequence and a disulfide bridge between sites 1 and 122 in chymotrypsin has been examined by comparing enzyme activities of wild-type and mutant enzymes. The kinetic constants of mutants devoid of the Cys1-Cys122 disulfide-linked propeptide show that this linkage is not important either for activity or substrate specificity. However this linkage appears to be the major factor in keeping the zymogen stable against non-specific activation. A comparison of zymogen stabilities showed that the trypsinogen propeptide is ten times more effective than the chymotrypsinogen propeptide in preventing non-specific zymogen activation during heterologous expression and secretion from yeast. This feature can also be transferred in trans to chymotrypsinogen; i.e. the chymotrypsin trypsin propeptide chimera forms a stable zymogen.     

Toward successful compliance with JCAHO standard NC.1

Recommendations resulting from a JCAHO survey can be a true blessing as they force nursing departments to assess critically their professional practice and documentation systems. Systematic preparation, begun at least two years prior to the survey, includes Nursing Administration, a Nursing Documentation Task Force and all staff nurses. Educational consultants assigned to each unit bring nurses up-to-date on nursing process and nursing diagnosis. Mock surveys and cross-training in chart review prepare staff nurses for confident participation in the accreditation process.     

Beyond the interpersonal circumplex in group psychotherapy: the structure and relationship to outcome of the Individual Group Member Interpersonal Process Scale

Development of a new scale to measure patient behavior in group psychotherapy, the Individual Group Member Interpersonal Process Scale (IGIPS), is described. This scale captures clinically important aspects of how patients act in group, including how they respond to the other group members. The IGIPS was applied to videotapes of the first four sessions of seven 15-session outpatient therapy groups (52 patients) in the Mental Health Department of a health maintenance organization. The scale was found to have five factors (Activity, Interpersonal Sensitivity, Comfort with Self, Self-Focus, and Psychological Mindedness). Patient behavior that was moderate on two IGIPS dimensions was connected with better outcome than was that of patients with more extreme behavior in either direction.     

Adopting a policy of reuse

In many firms' experience, reusing elements of proven systems designs and software is best done through a companywide program. Reuse means savings in design, testing, manufacturing and support. The author gives the basic information a company needs to get started. The author discusses the context for reuse, planning and strategy involved in a reuse program     

A neural network that predicts psychiatric length of stay

One hundred and twelve bilateral thyroidectomies for solitary thyroid nodules with suspected malignancy were performed. The incidence of malignancy in the 112 primary nodules was 42%. Twenty-nine of the 112 contralateral lobes (26%) contained malignancy, which was unsuspected in 80%. Of these 29, 20 were foci of papillary cancer < or = 5 mm and 9 were larger papillary tumors or follicular carcinoma. We analyzed these 112 patients to determine whether there was a simple method to identify those patients at risk for contralateral, unsuspected malignancy. With use of the AMES clinical staging retrospectively, 70 of the 112 patients were classified as having low-stage disease. Fifty percent (35) had cancers on the primary side and 27% (19) on the contralateral side. Of these 19 contralateral cancers, 14 were papillary cancers < or = 5 mm, 4 were papillary cancer > 5 mm and one was a 1.5 cm follicular carcinoma, a similar distribution as in the whole group of 112. When the AMES analysis then excluded those thought to be at risk for multicentricity or papillary carcinoma and examined female patients only with nonpapillary frozen sections, nonpapillary aspiration cytological results, and no history of radiation exposure, no further reduction in the proportion of contralateral cancers (7 of 26, 27%) was found. Fifty-five of the 112 patients underwent preoperative ultrasound scans. In those cases in whom the contralateral lobe had no intraoperative palpable or preoperative sonographic mass, 5 of 20 still had contralateral cancers, but all were papillary < or = 5 mm.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dissolved organic carbon of coal slurry transport water

The qualitative and quantitative occurrence and fate of dissolved organic carbon (DOC) leaching into coal slurry transport water was examined in laboratory-generated coal slurries and wastewaters from the Black Mesa coal slurry pipeline. Laboratory slurries were formulated for both western coals (Wyodak, Montana Rosebud and Black Mesa) and eastern coals (Illinois No. 6 and Pittsburgh No. 8). Sephadex G-25 elution profiles and ultrafiltration studies indicate that the majority of the organic compounds in western coal slurry wastewaters were lower (less than 1000) molecular weight species (62% for Wyodak and 74% for Montana Rosebud). Biochemical Oxygen Demand (BOD) for these particular wastewaters ranged from 50 to 150 mg l⁻¹ as determined through the use of an electrolytic respirometer. Also, there was a concomitant 51–74% reduction in the DOC levels in the wastewaters. This removal was primarily due to the removal of the lower (< 1000) molecular weight compounds by the seed inoculum. There was no evidence for the presence of mutagenic organics in the raw wastewater.     

Kinetic analysis of the crystallization of poly(p-phenylene sulphide)

Growth rates of spherulites were measured in poly(p-phenylene sulphide) crystallized from the melt and the quenched glass over the temperature range 100°C–280°C, possibly the most extensive overall range yet reported for any polymer and, as such, most propitious for study of régime III crystallization. For a medium M.wt. polymer, a régime II → III transition was obtained at 208°C using values of transport parameters common to many polymers ($\text{U1 = 1400}\text{cal mol}{}^{\mathrm{?1}}$, T_∞ ? T_g = 30°C) together with experimentally determined values of T⁰_m(315°C) and T_g(92°C). Under these conditions, the régime III/II slope ratio was found to be 2.07 (i.e. only 3.5% higher than predicted by régime theory), and reasonable estimates of surface free energies and of the work of chain folding were obtained. Other choices of the transport terms, including WLF and zero values, did not allow successful kinetic analyses. Although a régime I → II transition is predicted to occur at the high-temperature end of our growth-rate data, we found no experimental evidence for it. For a low M.wt. polymer, our analysis showed that régime III kinetics is obeyed at low temperatures, while at higher ones there is a continuous departure from that behaviour without, however, full attainment of régime II kinetics.