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211.
El-Bestawy E Hussein H Baghdadi HH El-Saka MF 《Journal of industrial microbiology & biotechnology》2005,32(5):195-203
The present work compared chemical and biological treatment methods to achieve the most efficient treatment for the reduction or elimination of phosphorus and nitrogen from mixed industrial–domestic wastewaters. Batch chemical precipitation by ferric chloride and aluminum sulfate (alum) and a continuous biological suspended growth system were investigated as well as the optimum operating conditions. Concerning chemical treatment, Alum generally achieved a higher removal efficiency percentage for the investigated pollutants compared with FeCl3 at their optimum pH and dose, especially with chemical oxygen demand (COD). FeCl3 treatment achieved success only with phosphorus removal, while none of the COD, 5-day biochemical oxygen demand (BOD5), total nitrogen (TN) and N–NH3 achieved acceptable treatment and remained above the maximum permissible limits (MPL). Thus, for such wastewaters, alum is more efficient than FeCl3. Biological treatment exhibited higher efficiencies, particularly towards nitrogen. TN removal increased by increasing the flow rate to 30–60 l/day. N–NH3 removal was effective at the slowest flow rate and decreased with increasing flow rate, while an opposite trend was recorded for N–NO3. At all flow rates, phosphorus levels were below the accepted MPL for discharging into natural systems. Moreover, there was a general trend for the proposed biological treatment to achieve a high removal efficiency for BOD5 and COD, bringing them to acceptable levels to be released into watercourses safely, especially at the slowest flow rates. Thus, integration between the proposed chemical and biological treatment is highly recommended, producing high-quality effluents acceptable by the environmental law. 相似文献
212.
Surfactant protein D binds selectively to Klebsiella pneumoniae lipopolysaccharides containing mannose-rich O-antigens 总被引:2,自引:0,他引:2
Sahly H Ofek I Podschun R Brade H He Y Ullmann U Crouch E 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(6):3267-3274
Surfactant protein D (SP-D) plays important roles in the regulation of innate immune responses in the lung. We have previously shown that SP-D can agglutinate and enhance the macrophage-dependent killing of specific unencapsulated phase variants of Klebsiella pneumoniae. In the present studies, we used 16 clinical isolates of Klebsiella representing four O-serotypes and examined the interaction of SP-D with their isolated LPSs. Although SP-D bound to the core oligosaccharide of rough LPS from all isolates, it selectively bound to smooth forms of LPS expressed by O-serotypes with mannose-rich repeating units in their O-polysaccharides. SP-D was more potent in agglutinating unencapsulated phase variants of O-serotypes expressing these SP-D "reactive" O-polysaccharides, and more effectively inhibited the adhesion of these serotypes to lung epithelial cells. This novel anti-adhesion activity required the multimerization of trimeric SP-D subunits (dodecamers). Klebsiella serotypes expressing "nonreactive" LPS O-Ags were isolated at a significantly higher frequency from patients with K. pneumoniae. Our findings suggest that SP-D plays important roles in the clearance of opportunistic Gram-negative bacteria and contributes to known serotypic differences in the pathogenicity of Klebsiella through specific interactions with O-polysaccharides. 相似文献
213.
214.
Tailor-made olefinic medium-chain-length poly[(R)-3-hydroxyalkanoates] by Pseudomonas putida GPo1: batch versus chemostat production 总被引:1,自引:0,他引:1
Hartmann R Hany R Pletscher E Ritter A Witholt B Zinn M 《Biotechnology and bioengineering》2006,93(4):737-746
Functionalized medium-chain-length polyhydroxyalkanoates (mclPHAs) have gained much interest in research on biopolymers because of their ease of chemical modification. Tailored olefinic mclPHA production from mixtures of octanoic acid and 10-undecenoic acid was investigated in batch and dual (C,N) nutrient limited chemostat cultures of Pseudomonas putida GPo1 (ATCC 29347). In a batch culture, where P. putida GPo1 was grown on a mixture of octanoic acid (58 mol%) and 10-undecenoic acid (42 mol%), it was found that the fraction of aliphatic monomers was slightly lower in mclPHA produced during exponential growth than during late stationary phase. Thus, the total monomeric composition changed over time indicating different kinetics for the two carbon substrates. Chemostat experiments showed that the dual (C,N) nutrient limited growth regime (DNLGR) for 10-undecenoic acid coincided with the one for octanoic acid. Five different chemostats on equimolar mixtures of octanoic acid and 10-undecenoic acid within the DNLGR revealed that the monomeric composition of mclPHA was not a function of the carbon to nitrogen (C(0)/N(0)) ratio in the feed medium but rather of the dilution rate. The fraction of aliphatic monomers in the accumulated mclPHA was slightly lower at high dilution rates and increased towards low dilution rates, again indicating different kinetics for the two carbon substrates in P. putida GPo1. 相似文献
215.
Probabilistic disease classification of expression-dependent proteomic data from mass spectrometry of human serum. 总被引:6,自引:0,他引:6
We have developed an algorithm called Q5 for probabilistic classification of healthy versus disease whole serum samples using mass spectrometry. The algorithm employs principal components analysis (PCA) followed by linear discriminant analysis (LDA) on whole spectrum surface-enhanced laser desorption/ionization time of flight (SELDI-TOF) mass spectrometry (MS) data and is demonstrated on four real datasets from complete, complex SELDI spectra of human blood serum. Q5 is a closed-form, exact solution to the problem of classification of complete mass spectra of a complex protein mixture. Q5 employs a probabilistic classification algorithm built upon a dimension-reduced linear discriminant analysis. Our solution is computationally efficient; it is noniterative and computes the optimal linear discriminant using closed-form equations. The optimal discriminant is computed and verified for datasets of complete, complex SELDI spectra of human blood serum. Replicate experiments of different training/testing splits of each dataset are employed to verify robustness of the algorithm. The probabilistic classification method achieves excellent performance. We achieve sensitivity, specificity, and positive predictive values above 97% on three ovarian cancer datasets and one prostate cancer dataset. The Q5 method outperforms previous full-spectrum complex sample spectral classification techniques and can provide clues as to the molecular identities of differentially expressed proteins and peptides. 相似文献
216.
Background
cMYC regulates approximately 15% of human genes and is involved in up to 20% of all human cancers. Reports discussing cMYC protein expression in thyroid carcinomas are limited, with controversies pertaining to cMYC expression patterns noted in the literature. The aims of the current study were to clarify patterns and intensities of cMYC expression in follicular cell-derived thyroid carcinomas across a spectrum of cancer morphologies and disease aggressivities, to correlate cMYC with BRAFV600E expression, and to evaluate the potential role of cMYC in progression of well-differentiated thyroid carcinomas into less well-differentiated carcinomas.Methods
Immunohistochemical studies using specific monoclonal antibodies for cMYC and BRAFV600E were performed on tissue microarrays built from follicular cell-derived thyroid carcinomas (25 papillary, 24 follicular, 24 oncocytic variant of follicular, and 21 undifferentiated). In addition, cMYC IHC testing was also performed on whole tissue tumor sections from a subset of patients. Nodular hyperplasia cases were used as non-neoplastic controls. Appropriate positive and negative controls were included.Results
cMYC was expressed almost exclusively in a nuclear fashion in both thyroid carcinomas and nodular hyperplasias. cMYC expression was weakly positive in both nodular hyperplasias and well-differentiated carcinomas. The majority of undifferentiated carcinomas (UDCs) showed strong nuclear cMYC positivity. PTC cases that were positive for cMYC (6/25) harbored the BRAF V600E mutation. A correlation was confirmed between cMYC intensity and tumor size in UDCs. UDC cases that developed out of well-differentiated thyroid carcinomas showed frank overexpression of cMYC in the undifferentiated tumor components.Conclusions
Our study suggests that nuclear overexpression of cMYC correlates with tumorigenesis / dedifferentiation in follicular cell derived thyroid carcinomas, a concept that has not been shown before on whole tissue sections.217.
218.
Dennis H. Lau Melissa E. Middeldorp Anthony G. Brooks Anand N. Ganesan Kurt C. Roberts-Thomson Martin K. Stiles Darryl P. Leong Hany S. Abed Han S. Lim Christopher X. Wong Scott R. Willoughby Glenn D. Young Jonathan M. Kalman Walter P. Abhayaratna Prashanthan Sanders 《PloS one》2013,8(10)
Background
Recent community-based research has linked aortic stiffness to the development of atrial fibrillation. We posit that aortic stiffness contributes to adverse atrial remodeling leading to the persistence of atrial fibrillation following catheter ablation in lone atrial fibrillation patients, despite the absence of apparent structural heart disease. Here, we aim to evaluate aortic stiffness in lone atrial fibrillation patients and determine its association with arrhythmia recurrence following radio-frequency catheter ablation.Methods
We studied 68 consecutive lone atrial fibrillation patients who underwent catheter ablation procedure for atrial fibrillation and 50 healthy age- and sex-matched community controls. We performed radial artery applanation tonometry to obtain central measures of aortic stiffness: pulse pressure, augmentation pressure and augmentation index. Following ablation, arrhythmia recurrence was monitored at months 3, 6, 9, 12 and 6 monthly thereafter.Results
Compared to healthy controls, lone atrial fibrillation patients had significantly elevated peripheral pulse pressure, central pulse pressure, augmentation pressure and larger left atrial dimensions (all P<0.05). During a mean follow-up of 2.9±1.4 years, 38 of the 68 lone atrial fibrillation patients had atrial fibrillation recurrence after initial catheter ablation procedure. Neither blood pressure nor aortic stiffness indices differed between patients with and without atrial fibrillation recurrence. However, patients with highest levels (≥75th percentile) of peripheral pulse pressure, central pulse pressure and augmentation pressure had higher atrial fibrillation recurrence rates (all P<0.05). Only central aortic stiffness indices were associated with lower survival free from atrial fibrillation using Kaplan-Meier analysis.Conclusion
Aortic stiffness is an important risk factor in patients with lone atrial fibrillation and contributes to higher atrial fibrillation recurrence following catheter ablation procedure. 相似文献219.
Giorgio Tasca Julien Yockell Lelievre Qing Qiu Kerri Ritchie John Little Anne Trinneer Ann Barber Livia Chyurlia Hany Bissada Andreé Gruslin 《PloS one》2013,8(12)
Intro
Binge eating disorder (BED) affects 3.5% of the population and is characterized by binge eating for at least 2 days a week for 6 months. Treatment options include cognitive behavioral therapy, interpersonal psychotherapy, and pharmacotherapy which are associated with varied success.Little is known about the biology of BED. Since there is evidence that the insulin like growth factor system is implicated in regulation of body weight, insulin sensitivity and feeding behavior, we speculated it may be involved in BED.Methods
A cross-sectional comparison was made between three groups of women: overweight with BED, overweight without BED and normal weight without BED. Women were assigned to Group Psychodynamic Interpersonal Psychotherapy. Blood was collected before therapy, at completion and at 6months follow up for evaluation of IGF-II using Western blot.Results
97 overweight women with BED contributed to the cross-sectional comparison. The two control groups comprised 53 overweight women without BED, and 50 age matched normal weight women without BED. Obese women had significantly lower Big IGF-II than normal weight women, p = .028; Overweight women with BED had higher Mature IGF-II than normal weight women, p<.05.Big IGF-II showed a significant decreasing slope from pre- to post- to six months post-group psychological treatment, unrelated to changes in BMI (p = .008).Conclusion
Levels of IGF-II isoforms differed significantly between overweight and normal weight women. Overweight women with BED display abnormal levels of circulating IGF-II isoforms. BED is characterized by elevated mature IGF-II, an isoform shown to carry significant bioactivity. This finding is not related to BMI or to changes in body weight. The results also provide preliminary evidence that BIG IGF-II is sensitive to change due to group psychological treatment. We suggest that abnormalities in IGF-II processing may be involved in the neurobiology of BED. 相似文献220.
Asfour IA Fayek M Raouf S Soliman M Hegab HM El-Desoky H Saleh R Moussa MA 《Biological trace element research》2007,120(1-3):1-10
The present study was undertaken to explore the effect of administration of high doses of sodium selenite on the expression
of Bcl-2 in patients with non-Hodgkin’s lymphoma (NHL). Fifty patients with newly diagnosed NHL were randomly divided into
two groups. Group A-I received standard chemotherapy whereas group A-II received adjuvant sodium selenite 0.2 mg kg−1 day−1 for 30 days in addition to chemotherapy. Enzyme-linked immunosorbent assay was used to assess Bcl-2 at the time of diagnosis
and after therapy in the two groups. Sodium selenite administration resulted in significant decline of Bcl-2 level after therapy
in group A-II (8.6 ± 6.9 ng/ml vs 3 6.9 ± 7.9 ng/ml, P < 0.05). Also, complete response reached 60% in group A-II compared to 40% in group A-I. Significant increase in CD4/CD8
ratio was noticed in group A-II compared to group A-I after therapy (1.45 ± 0.36 vs 1.10 ± 0.28 p 0.04). Overall survival
time in months was significantly longer in complete remission patients in group A-II (21.87 ± 1.41) compared to group A-I
(19.70 ± 1.95) (p = 0.01). It is concluded that sodium selenite administration at the dosage and duration chosen acts as a downregulator of
Bcl-2 and improves clinical outcome. 相似文献