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91.
Anwar J Shafique U Waheed-uz-Zaman un Nisa Z Munawar MA Jamil N Salman M Dar A Rehman R Saif J Gul H Iqbal T 《International journal of phytoremediation》2011,13(5):410-420
Adsorption is an environmental friendly process for removal and/or recovery of heavy metals from wastewater. In recent years, it has been substantiated as a popular technique to treat industrial waste effluents, with significant advantages. In this work, batchwise removal of chromium (III) ions from water by Polyalthia longifolia leaves was studied as a function of adsorbent dose, pH, contact time, and agitation speed. Surface characteristics of the leaves were evaluated by recording IR spectra. The Langmuir, Freundlich, and Temkin adsorption isotherms were employed to explain the sorption process. It was found that one gram of leaves can remove 1.87 mg of trivalent chromium when working at pH 3.0. It has been concluded that Polyalthia longifolia leaves can be used as cost-effective and benign adsorbents for removal of Cr(III) ions from wastewater. 相似文献
92.
Kangwana BP Kedenge SV Noor AM Alegana VA Nyandigisi AJ Pandit J Fegan GW Todd JE Brooker S Snow RW Goodman CA 《PLoS medicine》2011,8(5):e1000437
Background
It has been proposed that artemisinin-based combination therapy (ACT) be subsidised in the private sector in order to improve affordability and access. This study in western Kenya aimed to evaluate the impact of providing subsidized artemether–lumefantrine (AL) through retail providers on the coverage of prompt, effective antimalarial treatment for febrile children aged 3–59 months.Methods and Findings
We used a cluster-randomized, controlled design with nine control and nine intervention sublocations, equally distributed across three districts in western Kenya. Cross-sectional household surveys were conducted before and after the delivery of the intervention. The intervention comprised provision of subsidized packs of paediatric ACT to retail outlets, training of retail outlet staff, and community awareness activities. The primary outcome was defined as the proportion of children aged 3–59 months reporting fever in the past 2 weeks who started treatment with AL on the same day or following day of fever onset. Data were collected using structured questionnaires and analyzed based on cluster-level summaries, comparing control to intervention arms, while adjusting for other covariates. Data were collected on 2,749 children in the target age group at baseline and 2,662 at follow-up. 29% of children experienced fever within 2 weeks before the interview. At follow-up, the percentage of children receiving AL on the day of fever or the following day had risen by 14.6% points in the control arm (from 5.3% [standard deviation (SD): 3.2%] to 19.9% [SD: 10.0%]) and 40.2% points in the intervention arm (from 4.7% [SD: 3.4%] to 44.9% [SD: 11.7%]). The percentage of children receiving AL was significantly greater in the intervention arm at follow-up, with a difference between the arms of 25.0% points (95% confidence interval [CI]: 14.1%, 35.9%; unadjusted p = 0.0002, adjusted p = 0.0001). No significant differences were observed between arms in the proportion of caregivers who sought treatment for their child''s fever by source, or in the child''s adherence to AL.Conclusions
Subsidizing ACT in the retail sector can significantly increase ACT coverage for reported fevers in rural areas. Further research is needed on the impact and cost-effectiveness of such subsidy programmes at a national scale.Trial Registration
Current Controlled Trials ISRCTN59275137 and Kenya Pharmacy and Poisons Board Ethical Committee for Clinical Trials PPB/ECCT/08/07. Please see later in the article for the Editors'' Summary 相似文献93.
Dworeck T Petri AK Muhammad N Fioroni M Schwaneberg U 《Protein expression and purification》2011,77(1):75-79
Membrane protein isolation is a challenging problem. In fact especially their extraction from the respective membrane is difficult and often goes along with losses in yield. Usually expensive detergents are needed to extract the target protein from the membrane. Therefore finding an efficient overexpression and extraction method and an alternative to detergents is desirable. In this study we describe a new and fast method to express, extract and purify an engineered variant of the FhuA protein (FhuA Δ1-159) that acts as passive diffusion channel, using a diblock copolymer as an alternative to detergents like octyl-POE (n-octylpolyoxyethylene). The N-terminal leader sequence, facilitating the protein's transport to the outer membrane was deleted (FhuA Δ1-159 Δsignal), resulting in protein accumulation in easy to isolate inclusion bodies. Urea was used to solubilise the unfolded protein and dialysis against phosphate-buffer containing the commercially available diblock copolymer PE-PEG[Polyethylene-Poly(ethyleneglycol)] lead to protein refolding. Circular dichroism spectroscopy revealed a high β-sheet percentage within the refolded protein secondary structure indicating the successful reconstitution of FhuA Δ1-159 Δsignal native state. Furthermore the channel functionality of FhuA Δ1-159 Δsignal was verified by measuring the in and out-flux through the protein when inserted into liposome membrane, using the HRP/TMB (HRP=Horse Radish Peroxidase, TMB=3,3',5,5'-tetramethylbenzidine) assay system. 相似文献
94.
Temperature and malaria trends in highland East Africa 总被引:1,自引:0,他引:1
Stern DI Gething PW Kabaria CW Temperley WH Noor AM Okiro EA Shanks GD Snow RW Hay SI 《PloS one》2011,6(9):e24524
There has been considerable debate on the existence of trends in climate in the highlands of East Africa and hypotheses about their potential effect on the trends in malaria in the region. We apply a new robust trend test to mean temperature time series data from three editions of the University of East Anglia's Climatic Research Unit database (CRU TS) for several relevant locations. We find significant trends in the data extracted from newer editions of the database but not in the older version for periods ending in 1996. The trends in the newer data are even more significant when post-1996 data are added to the samples. We also test for trends in the data from the Kericho meteorological station prepared by Omumbo et al. We find no significant trend in the 1979-1995 period but a highly significant trend in the full 1979-2009 sample. However, although the malaria cases observed at Kericho, Kenya rose during a period of resurgent epidemics (1994-2002) they have since returned to a low level. A large assembly of parasite rate surveys from the region, stratified by altitude, show that this decrease in malaria prevalence is not limited to Kericho. 相似文献
95.
The aim of this study was to determine the cytotoxic and apoptotic effects of erythrocarpine E (CEB4), a limonoid extracted from Chisocheton erythrocarpus on human oral squamous cell carcinoma. Based on preliminary dimethyl-2-thiazolyl-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays, CEB4 treated HSC-4 cells demonstrated a cytotoxic effect and inhibited cell proliferation in a time and dose dependent manner with an IC(50) value of 4.0±1.9 μM within 24 h of treatment. CEB4 was also found to have minimal cytotoxic effects on the normal cell line, NHBE with cell viability levels maintained above 80% upon treatment. Annexin V-fluorescein isothiocyanate (FITC), poly-ADP ribose polymerase (PARP) cleavage and DNA fragmentation assay results showed that CEB4 induces apoptosis mediated cell death. Western blotting results demonstrated that the induction of apoptosis by CEB4 appeared to be mediated through regulation of the p53 signalling pathway as there was an increase in p53 phosphorylation levels. CEB4 was also found to up-regulate the pro-apoptotic protein, Bax, while down-regulating the anti-apoptotic protein, Bcl-2, suggesting the involvement of the intrinsic mitochondrial pathway. Reduced levels of initiator procaspase-9 and executioner caspase-3 zymogen were also observed following CEB4 exposure, hence indicating the involvement of cytochrome c mediated apoptosis. These results demonstrate the cytotoxic and apoptotic ability of erythrocarpine E, and suggest its potential development as a cancer chemopreventive agent. 相似文献
96.
Bibi NS Gavara PR Soto Espinosa SL Grasselli M Fernández-Lahore M 《Biotechnology progress》2011,27(5):1329-1338
The preparation of megaporous bodies, with potential applications in biotechnology, was attempted by following several strategies. As a first step, naive and robust scaffolds were produced by polymerization of selected monomers in the presence of a highly soluble cross‐linker agent. Ion‐exchange function was incorporated by particle embedding, direct chemical synthesis, or radiation‐induced grafting. The total ionic capacity of such systems was 1.5 mmol H+/g, 1.4 mmol H+/g, and 17 mmol H+/g, respectively. These values were in agreement with the ability to bind model proteins: observed dynamic binding capacity at 50% breakthrough was ?7.2 mg bovine serum albumin/g, ?7.4 hen egg‐white lysozyme (HEWL) mg/g, and ?108 HEWL mg/g. In the later case, total (static) binding capacity reached 220 mg/g. It was observed that the structure and size of the megapores remained unaffected by the grafting procedure which, however, allowed for the highest protein binding capacity. Lysozyme supported on grafted body showed extensive clarification activity against a Micrococcus lysodekticus suspension in the flow‐through mode, i.e., 90% destruction of suspended microbial cells was obtained with a residence time ≈ 18 min. Both protein capture and biocatalysis applications are conceivable with the 3D‐megaporous materials described in this work. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011 相似文献
97.
98.
Kanaani J Prusiner SB Diacovo J Baekkeskov S Legname G 《Journal of neurochemistry》2005,95(5):1373-1386
While a beta-sheet-rich form of the prion protein (PrPSc) causes neurodegeneration, the biological activity of its precursor, the cellular prion protein (PrPC), has been elusive. We have studied the effect of purified recombinant prion protein (recPrP) on rat fetal hippocampal neurons in culture. Overnight exposure to Syrian hamster or mouse recPrP, folded into an alpha-helical-rich conformation similar to that of PrPC, resulted in a 1.9-fold increase in neurons with a differentiated axon, a 13.5-fold increase in neurons with differentiated dendrites, a fivefold increase in axon length, and the formation of extensive neuronal circuitry. Formation of synaptic-like contacts was increased by a factor of 4.6 after exposure to recPrP for 7 days. Neither the N-terminal nor C-terminal domains of recPrP nor the PrP paralogue doppel (Dpl) enhanced the polarization of neurons. Inhibitors of protein kinase C (PKC) and of Src kinases, including p59Fyn, blocked the effect of recPrP on axon elongation, while inhibitors of phosphatidylinositol 3-kinase showed a partial inhibition, suggesting that signaling cascades involving these kinases are candidates for transduction of recPrP-mediated signals. The results predict that full-length PrPC functions as a growth factor involved in development of neuronal polarity. 相似文献
99.
Baig S Damian RT Morales-Montor J Olecki P Talhouk J Hashmey R White AC 《The Journal of parasitology》2005,91(5):983-987
Cysticercosis is caused by Taenia spp. metacestodes, which must survive in the host tissues to complete their life cycle. Their survival depends on their control of host immune responses. Because many parasites use proteases to modulate host responses, we examined culture media from Taenia crassiceps metacestodes for protease activity using peptide substrates. We identified prominent aminopeptidase activity at neutral pH, which was inhibited by chelating agents and partially inhibited by the aminopeptidase inhibitor, bestatin. Endopeptidase substrates were optimally cleaved at slightly acidic pH and endopeptidase activity was inhibited by cysteine protease inhibitors. Gel filtration FPLC and subsequent visualization by silver staining revealed a metallo-aminopeptidase of molecular weight 21 kDa and cysteine proteases of Mr 70 and 64 kDA. Recombinant IL-2 was digested when incubated with parasite culture supernatants, but not with control media. IL-2 degradation was completely inhibited by 1,10 phenanthroline and partially inhibited by bestatin, suggesting that a metallo-aminopeptidase was responsible. Incubation of human IgG with culture supernatants resulted in complete degradation of IgG, which was blocked by cysteine protease inhibitors. These observations demonstrate that Taenia spp. metacestodes secrete a number of proteolytic enzymes, which may target molecules from the host immune system and assist in evasion of the host immune response. 相似文献
100.
Slotnick MJ Nriagu JO Johnson MM Linder AM Savoie KL Jamil HJ Hammad AS 《Biological trace element research》2005,107(2):113-126
Exposure to environmental contaminants is complicated by factors related to socioeconomic status, diet, and other culturally
conditioned risk behaviors. Determination of a trace element profile in toenails can be used as a tool in biomonitoring the
exposure history or assessing the deficiency of a particular element in a study population, which can lead to a better understanding
of environmental and disease risks. Toenail clippings from 259 Arab Americans (163 adults, 96 children) residing in a highly
industrialized area were analyzed for Al, V, Cr, Mn, Co, Ni, Cu, As, Se, Mo, Cd, Ba, Tl, and Pb using an inductively coupled
plasma-mass spectrometer. Mean concentrations were compared with published values, and the influence of age, gender, and other
demographic factors were explored. Elevated levels of Ni in this population warrant further investigation. Significant differences
in the mean concentration of Al, V, Cr, Mn, Cd, Pb, and Se exist between toenails of adults and children. Pearson correlation
coefficients reveal strong significant associations among Cd, Cr, and Tl (p<0.05), in addition to other elements. These investigations provide insight into exposures and factors influencing exposures
in this population while adding to the growing fund of knowledge surrounding use of toenails as a marker of exposure. 相似文献