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51.
52.
Islam MS Rahman MZ Khan SI Mahmud ZH Ramamurthy T Nair GB Sack RB Sack DA 《Microbiology and immunology》2005,49(8):779-784
The organization of the CTX prophage in environmental strains of Vibrio mimicus was investigated. Sixteen hundred non-sucrose fermenting vibrios were examined for ctx gene by hybridization. Out of 1,600 isolates, 6 V. mimicus isolates contained ctxA gene. The organization of CTX prophage was determined by RFLP using ctxA probe. The CTX prophage integrated at a single site in V. mimicus genome which was present as a single copy flanked by at least a single RS element. Ribotype pattern revealed that a particular clone of V. mimicus acquired the CTXPhi in the aquatic environment. This study demonstrated that V. mimicus could act as a reservoir of CTXPhi in the aquatic environment. 相似文献
53.
Huq A Sack RB Nizam A Longini IM Nair GB Ali A Morris JG Khan MN Siddique AK Yunus M Albert MJ Sack DA Colwell RR 《Applied and environmental microbiology》2005,71(8):4645-4654
The occurrence of outbreaks of cholera in Africa in 1970 and in Latin America in 1991, mainly in coastal communities, and the appearance of the new serotype Vibrio cholerae O139 in India and subsequently in Bangladesh have stimulated efforts to understand environmental factors influencing the growth and geographic distribution of epidemic Vibrio cholerae serotypes. Because of the severity of recent epidemics, cholera is now being considered by some infectious disease investigators as a "reemerging" disease, prompting new work on the ecology of vibrios. Epidemiological and ecological surveillance for cholera has been under way in four rural, geographically separated locations in Bangladesh for the past 4 years, during which both clinical and environmental samples were collected at biweekly intervals. The clinical epidemiology portion of the research has been published (Sack et al., J. Infect. Dis. 187:96-101, 2003). The results of environmental sampling and analysis of the environmental and clinical data have revealed significant correlations of water temperature, water depth, rainfall, conductivity, and copepod counts with the occurrence of cholera toxin-producing bacteria (presumably V. cholerae). The lag periods between increases or decreases in units of factors, such as temperature and salinity, and occurrence of cholera correlate with biological parameters, e.g., plankton population blooms. The new information on the ecology of V. cholerae is proving useful in developing environmental models for the prediction of cholera epidemics. 相似文献
54.
Wastewater-grown duckweed may be safely used as fish feed 总被引:2,自引:0,他引:2
Islam MS Kabir MS Khan SI Ekramullah M Nair GB Sack RB Sack DA 《Canadian journal of microbiology》2004,50(1):51-56
Duckweed has been used for the treatment of wastewater and as fish feed. A comparative study was carried out to determine (i) the efficacy of duckweed in treating hospital-based wastewater and (ii) the level of the microbial contamination of fish fed on wastewater-grown duckweed. There were two groups of ponds where fish farming was done. In one group of ponds (control ponds), duckweed that was grown using artificial fertilizer was used as fish feed; in another group (study ponds), wastewater-grown duckweed was used as fish feed. The faecal contamination of water, duckweed, and fish from study and control ponds were monitored by faecal coliform estimation. The presence of enteric pathogens among handlers, water, duckweed, and fish samples was also examined. It was observed that the faecal coliform counts of raw wastewater were 4.7 Log10 CFU/mL, which was reduced to <1 Log10 CFU/mL after treating with duckweed. There was no significant difference (P > 0.05) in faecal coliform counts in water collected from duckweed ponds and fish ponds of study and control areas. The wastewater-grown duckweed did not pose any health hazard to the handlers. These results demonstrated that the wastewater-treated duckweed may be safely used as fish feed. 相似文献
55.
Novel aspects of systems biology and clinical cytomics. 总被引:1,自引:0,他引:1
József Bocsi Anja Mittag Ulrich Sack Andreas O H Gerstner Markus J Barten Attila Tárnok 《Cytometry. Part A》2006,69(3):105-108
The area of Cytomics and Systems Biology became of great impact during the last years. In some fields of the leading cytometric techniques it represents the cutting edge today. Many different applications/variations of multicolor staining were developed for flow- or slide-based cytometric analysis of suspensions and sections to whole animal analysis. Multispectral optical imaging can be used for studying immunological and tumorigenic processes. New methods resulted in the establishment of lipidomics as the systemic research of lipids and their behavior. All of these development push the systemic approach of the analysis of biological specimens to enhance the outcome in the clinic and in drug discovery programs. 相似文献
56.
Leaf hydraulic conductance (K(leaf)) is a major determinant of photosynthetic rate in well-watered and drought-stressed plants. Previous work assessed the decline of K(leaf) with decreasing leaf water potential (Ψ(leaf)), most typically using rehydration kinetics methods, and found that species varied in the shape of their vulnerability curve, and that hydraulic vulnerability correlated with other leaf functional traits and with drought sensitivity. These findings were tested and extended, using a new steady-state evaporative flux method under high irradiance, and the function for the vulnerability curve of each species was determined individually using maximum likelihood for 10 species varying strongly in drought tolerance. Additionally, the ability of excised leaves to recover in K(leaf) with rehydration was assessed, and a new theoretical framework was developed to estimate how rehydration of measured leaves may affect estimation of hydraulic parameters. As hypothesized, species differed in their vulnerability function. Drought-tolerant species showed shallow linear declines and more negative Ψ(leaf) at 80% loss of K(leaf) (P(80)), whereas drought-sensitive species showed steeper, non-linear declines, and less negative P(80). Across species, the maximum K(leaf) was independent of hydraulic vulnerability. Recovery of K(leaf) after 1 h rehydration of leaves dehydrated below their turgor loss point occurred only for four of 10 species. Across species without recovery, a more negative P(80) correlated with the ability to maintain K(leaf) through both dehydration and rehydration. These findings indicate that resistance to K(leaf) decline is important not only in maintaining open stomata during the onset of drought, but also in enabling sustained function during drought recovery. 相似文献
57.
SIRT3 (sirtuin 3) modulates respiration via the deacetylation of lysine residues in electron transport chain proteins. Whether mitochondrial protein acetylation is controlled by a counter-regulatory program has remained elusive. In the present study we identify an essential component of this previously undefined mitochondrial acetyltransferase system. We show that GCN5L1 [GCN5 (general control of amino acid synthesis 5)-like 1; also known as Bloc1s1] counters the acetylation and respiratory effects of SIRT3. GCN5L1 is mitochondrial-enriched and displays significant homology with a prokaryotic acetyltransferase. Genetic knockdown of GCN5L1 blunts mitochondrial protein acetylation, and its reconstitution in intact mitochondria restores protein acetylation. GCN5L1 interacts with and promotes acetylation of SIRT3 respiratory chain targets and reverses global SIRT3 effects on mitochondrial protein acetylation, respiration and bioenergetics. The results of the present study identify GCN5L1 as a critical prokaryote-derived component of the mitochondrial acetyltransferase programme. 相似文献
58.
Schroeder GM Wei D Banfi P Cai ZW Lippy J Menichincheri M Modugno M Naglich J Penhallow B Perez HL Sack J Schmidt RJ Tebben A Yan C Zhang L Galvani A Lombardo LJ Borzilleri RM 《Bioorganic & medicinal chemistry letters》2012,22(12):3951-3956
5-Butyl-1,4-diphenyl pyrazole and 2-amino-5-chloro pyrimidine acylsulfonamides were developed as potent dual antagonists of Bcl-2 and Bcl-xL. Compounds were optimized for binding to the I88, L92, I95, and F99 pockets normally occupied by pro-apoptotic protein Bim. An X-ray crystal structure confirmed the proposed binding mode. Observation of cytochrome c release from isolated mitochondria in MV-411 cells provides further evidence of target inhibition. Compounds demonstrated submicromolar antiproliferative activity in Bcl-2/Bcl-xL dependent cell lines. 相似文献
59.
Christiane Fueldner Anja Mittag Jens Knauer Maria Biskop Pierre Hepp Roger Scholz Ulf Wagner Ulrich Sack Frank Emmrich Attila Tárnok Joerg Lehmann 《Arthritis research & therapy》2012,14(1):R8-9
Introduction
Suitable biomarkers are essential for therapeutic strategies in personalized medicine in terms of diagnosis as well as of prognosis. With highly specific biomarkers, it is possible, for example, to identify patients with poor prognosis, which enables early intervention and intensive treatment. The aim of this study was to identify and validate biomarkers and possible combinations for a prospective use in immunoscintigraphy, which may improve diagnosis of rheumatoid arthritis (RA) patients with consideration of inflammatory activity in the affected joints. Therefore, we tested several monoclonal antibodies (mAbs) directed against cellular-surface molecules on cells likely to be involved in the pathogenesis of RA.Methods
Synovial tissue from patients with long-standing RA (accompanied by synovitis with varying states of current activity) and patients with acute non-RA arthritis were stained for surface molecules on different cell types by using fluorochrome-labeled antibodies. Tissue analysis was done by laser scanning cytometry (LSC), and statistical evaluation, by discriminant analysis and ROC analysis.Results
CD11b, HLA-DR, CD90, and CD64 revealed significant differences between tissues from patients with RA and acute non-RA arthritis. Especially with the expression of CD64, both patient cohorts could be discriminated with high sensitivity and specificity. RA classification was improved by simultaneously investigating the expression of two or three different surface proteins, such as HLA-DR, CD90, and CD29 in the tissue. The simultaneous analysis of CD64 together with CD304 or the combination of CD11b and CD38 was suitable for the identification of RA patients with high current activity in synovitis.Conclusions
In this study, we showed that LSC is a novel reliable method in biomarker prevalidation in RA. Hence, identified mAbs in situ may allow their potential use in in vivo approaches. Moreover, we proved that biomarker-combination analysis resulted in better discrimination than did single-marker analysis. Combinations of these markers make a novel and reliable panel for the discrimination between RA and acute non-RA arthritis. In addition, further expedient combinations may be novel promising biomarker panels to identify current activity in synovitis in RA. 相似文献60.
R Hashim AM Khatib G Enwere JK Park R Reyburn M Ali NY Chang DR Kim B Ley K Thriemer AL Lopez JD Clemens JL Deen S Shin C Schaetti R Hutubessy MT Aguado MP Kieny D Sack S Obaro AJ Shaame SM Ali AA Saleh L von Seidlein MS Jiddawi 《PLoS neglected tropical diseases》2012,6(7):e1743