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81.
Effect of resin disinfectants-I3 and -I5 on Giardia muris and Giardia lamblia. 总被引:3,自引:1,他引:2 下载免费PDF全文
The resin-I5 column developed in our laboratories rendered aqueous suspensions containing up to 5 X 10(4) cysts of Giardia muris or Giardia lamblia per ml incapable of excystation. The inhibition of excystation was effective at both 4 and 25 degrees C. The addition of Na2S2O3 to column eluates containing cysts appeared to partially reverse the disinfectant action, and the reversal was more pronounced at 4 degrees C than at 25 degrees C. In contrast, the rapid removal of cysts from the column eluates by centrifugation and filtration or the use of other reductants, notably cysteine and glutathione, did not similarly reverse the disinfectant properties of the column. Based on these data, we suggest that the disinfecting agent is acquired by the cyst in its passage through the resin column and that either the disinfecting agent or its reaction can be partially and specifically neutralized by Na2S2O3. We hypothesize that the time between disinfectant acquisition and activity is a function of the thickness of the Giardia cyst wall and consequently takes longer at the lower temperature. Nevertheless, resin-I5 appears to inactivate a larger number of cysts in a shorter period of time with lower residual halogen levels than do agents of other published methods. 相似文献
82.
83.
Genetic characterization of the Klebsiella pneumoniae waa gene cluster, involved in core lipopolysaccharide biosynthesis 下载免费PDF全文
Regué M Climent N Abitiu N Coderch N Merino S Izquierdo L Altarriba M Tomás JM 《Journal of bacteriology》2001,183(12):3564-3573
A recombinant cosmid containing genes involved in Klebsiella pneumoniae C3 core lipopolysaccharide biosynthesis was identified by its ability to confer bacteriocin 28b resistance to Escherichia coli K-12. The recombinant cosmid contains 12 genes, the whole waa gene cluster, flanked by kbl and coaD genes, as was found in E. coli K-12. PCR amplification analysis showed that this cluster is conserved in representative K. pneumoniae strains. Partial nucleotide sequence determination showed that the same genes and gene order are found in K. pneumoniae subsp. ozaenae, for which the core chemical structure is known. Complementation analysis of known waa mutants from E. coli K-12 and/or Salmonella enterica led to the identification of genes involved in biosynthesis of the inner core backbone that are shared by these three members of the Enterobacteriaceae. K. pneumoniae orf10 mutants showed a two-log-fold reduction in a mice virulence assay and a strong decrease in capsule amount. Analysis of a constructed K. pneumoniae waaE deletion mutant suggests that the WaaE protein is involved in the transfer of the branch beta-D-Glc to the O-4 position of L-glycero-D-manno-heptose I, a feature shared by K. pneumoniae, Proteus mirabilis, and Yersinia enterocolitica. 相似文献
84.
Claudia Palladino Verónica Briz José María Bellón Francisco J. Climent Santiago J. de Ory María José Mellado María Luisa Navarro José T. Ramos Nuno Taveira María Isabel de José María ángeles Mu?oz-Fernández on the behalf of the CoRISpeS-Madrid Cohort Working Group 《PloS one》2014,9(5)
Objectives
To investigate the duration of sequential HAART regimens and predictors of first-line regimen discontinuation among HIV-1 vertically infected children and adolescents.Design
Multicentre survey of antiretroviral-naïve patients enrolled in the HIV-Paediatric Cohor,t CoRISpeS-Madrid Cohort, Spain.Methods
Patients with a follow-up of ≥1 month spent on HAART, with available baseline CD4 count and HIV-viral load (VL) were included. Time spent on sequential HAART regimens was estimated and multivariable regression was used to identify predictors of time to first-line regimen discontinuation.Results
104 patients were followed for a median 8 years after starting HAART among 1996–2012; baseline %CD4 was 21.5 (12.3–34.0)and viral load was 5.1 (4.6–5.6) log10 copies/mL. Patients received a mean of 1.9 regimens. Median time on first-line HAART (n = 104) was 64.5 months; second HAART (n = 56) 69.8 months; and third HAART (n = 21) 66.5 months. Eleven (11%) patients were lost to follow-up while on first-line HAART and 54% discontinued (cumulative incidence of 16% and 38% by 1 and 3-year, respectively). The main predictor of first-line regimen discontinuation was suboptimal adherence to antiretrovirals (AHR: 2.60; 95% CI: 1.44–4.70).Conclusions
Adherence to therapy was the main determinant of the duration of the first-line HAART regimen in children. It is important to identify patients at high risk for non-adherence, such as very young children and adolescents, in provide special care and support to those patients. 相似文献85.
86.
Ten isolates of Salmonella infantis (serologically typed) were found in litter and runoff collected from two experimental feedlots near the Kansas State University campus. Pathogenic implications are discussed relative to recreation water sites. Agricultural runoff maybe a source of viable salmonellae. 相似文献
87.
Immunological properties of rat phosphoglycerate mutase isozymes 总被引:1,自引:0,他引:1
In mammalian tissues three phosphoglycerate mutase (D-phosphoglycerate 2,3-phosphomutase, EC 5.4.2.1) isozymes result from the homo-dimeric and hetero-dimeric combinations of two subunits (types M and B). Whereas rabbit antisera against type M subunit (purified from rat muscle) and against type BB isozyme (purified from rat brain) possessed a high degree of specificity, both antisera reacted with type BB and MM isozymes, as demonstrated by immunoneutralization and ELISA. Both the M subunit and B subunit were more immunoreactive than their respective dimeric isozymes. Subunits type M and B may possess common antigenic determinants, and some of these determinants may be sterically hindered in their dimeric structures. 相似文献
88.
Ferran Roca Carbonell Erwin Martin Hernandez Ocampo Jose Maria Aragonès Pascual Eulalia Soler Fina Clapera Joan Espaulella Panicot 《Revista espa?ola de geriatría y gerontología》2014
Introduction
The aim of this study is to determine clinical features and interventions in patients attended in our hospital falls prevention unit.Material and methods
Medical records and evaluation protocols from October 2010 to June 2012 were reviewed. Results are expressed in means and standard deviation.Results
We studied 68 patients: 53 came due to falls (77.9%), and 15 (22%) due to gait disorders. The mean age was 77.6±7.9. Number of women: 63 (92.6%). Previous Barthel Index was 94/100, cognitive impairment 23 (33.8%), polypharmacy 69.1%, orthostatic hypotension 18 (26.4%). Walking speed 0.66± 0.19 m/s and Time up and go to (TUG) 16.6±4.5 s. Post-urography detected vestibular dysfunction in 34 patients (77%). Clinical cause of fall and/or gait disorder was multifactorial in 33 (48.5%), Parkinsonism 19 (27.9%), chronic pain/arthropathy 8 (11.4%), and vestibular syndrome 8 (11.4%). Two-thirds (45; 66.1%) of the patients began Physical therapy, and vitamin D was given to 47 (69.1%). Phone calls were made to patients and/or their relatives and noted that after 3 months of the treatment: 48 (70.5%) had no fall; 59 (86.7%) patients followed the recommendations, and 57 (83.8%) were satisfied.Conclusions
In this sample of older patients, mostly female with a good functional and cognitive condition, the causes of the falls were multifactorial in the half of the cases, and the post-urography detected vestibular changes in the half of the patients. 相似文献89.
Monteleone G Franchi L Fina D Caruso R Vavassori P Monteleone I Calabrese E Naccari GC Bellinvia S Testi R Pallone F 《Cell death and differentiation》2006,13(2):202-211
Recent studies have suggested that 5-aminosalicylic acid (5-ASA) inhibits colorectal cancer (CRC) development. However, the mechanism underlying the antineoplastic effect of 5-ASA remains unknown. We here examined the effect of 5-ASA on epidermal growth factor receptor (EGFR) activation, a pathway that triggers mitogenic signals in CRC cells. We show that 5-ASA inhibits EGFR activation, through a mechanism that does not rely on CRC cell death induction. 5-ASA enhances the activity, but not expression, of phosphorylated (p)-EGFR-targeting phosphatases (PTPs), and treatment of cells with PTP inhibitors abrogates the 5-ASA-mediated EGFR dephosphorylation. Both SH-PTP1 and SH-PTP2 interact with EGFR upon 5-ASA treatment. However, knockdown of SH-PTP2 but not SH-PTP1 by small interference RNAs prevents the 5-ASA-induced EGFR dephosphorylation. Finally, we show that 5-ASA attenuates p-EGFR in ex vivo organ cultures of CRC explants. Data indicate that 5-ASA disrupts EGFR signalling by enhancing SH-PTP2 activity, and suggest a mechanism by which 5-ASA interferes with CRC growth. 相似文献
90.
Pacheco R Oliva H Martinez-Navío JM Climent N Ciruela F Gatell JM Gallart T Mallol J Lluis C Franco R 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(10):6695-6704
Adaptive immune responses begin after productive immunosynaptic contacts formation established in secondary lymphoid organs by dendritic cells (DC) presenting the Ag to T lymphocytes. Despite its resemblance to the neurosynapse, the participation of soluble small nonpeptidic mediators in the intercellular cross-talk taking place during T cell-DC interactions remains poorly studied. In this study, we show that human DC undergoing maturation and in contact with T cells release significant amounts of glutamate, which is the main excitatory neurotransmitter in mammalians. The release of glutamate is nonvesicular and mediated by the DC-expressed Xc- cystine/glutamate antiporter. DC-derived glutamate stimulating the constitutively expressed metabotropic glutamate receptor 5 impairs T cell activation. However, after productive Ag presentation, metabotropic glutamate receptor 1 is expressed in T cells to mediate enhanced T cell proliferation and secretion of Th1 and proinflammatory cytokines. These data suggest that, during T cell-DC interaction, glutamate is a novel and highly effective regulator in the initiation of T cell-mediated immune responses. 相似文献