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1.
The effects of cage fish farming on physico-chemical and bacteriological water quality in Lake Volta, Ghana, were investigated in 2013–2014. Farmed and unfarmed (control) areas of the lake were selected for monitoring. Nutrients, temperature, dissolved oxygen, conductivity, turbidity, pH, total coliforms, Pseudomonas and Vibrio spp. in the water were monitored monthly. Analyses of the water samples were carried out according to standard procedures. Physico-chemical quality of the water in both farm and control sites were within ranges typical of minimally impacted water and did not vary significantly between the two contrasting sites. The bacteriological analysis, however, revealed contamination of the lake water by fish farming. The bacterial counts at the farmed sites were significantly higher (p < 0.05) than those of the control sites, with figures at the farmed sites ranging from 132 to 1 708 cfu 100 ml?1 for total coliforms, 514 to 5 170 cfu 100 ml?1 Pseudomonas spp. and 14 to 516 cfu 100 ml?1 for Vibrio spp. The results suggested that cage fish farming has increased bacterial loads in the lake water, but has had minimal impact on its physico-chemical quality.  相似文献   
2.
This paper presents a software library, nicknamed BATS, for some basic sequence analysis tasks. Namely, local alignments, via approximate string matching, and global alignments, via longest common subsequence and alignments with affine and concave gap cost functions. Moreover, it also supports filtering operations to select strings from a set and establish their statistical significance, via z-score computation. None of the algorithms is new, but although they are generally regarded as fundamental for sequence analysis, they have not been implemented in a single and consistent software package, as we do here. Therefore, our main contribution is to fill this gap between algorithmic theory and practice by providing an extensible and easy to use software library that includes algorithms for the mentioned string matching and alignment problems. The library consists of C/C++ library functions as well as Perl library functions. It can be interfaced with Bioperl and can also be used as a stand-alone system with a GUI. The software is available at http://www.math.unipa.it/~raffaele/BATS/ under the GNU GPL.  相似文献   
3.
This paper presents a summary of reported cases of Serious Adverse Events (SAEs) following treatment with Mectizan® (ivermectin, Merck, Sharpe &; Dohme) in onchocerciasis mass treatment programs from January 1, 1989 to December 31, 2001 through a passive surveillance system. A total of 207 SAE cases were reported out of approximately 165 million reported treatments delivered during the period under review, giving rise to a cumulative incidence of 1 reported SAE per 800,000 reported treatments. The mean age was 40 years and 70% of the cases were males. The mean time between ivermectin intake and onset of illness was 1 day. For 57% of the cases (n = 118), that was their first exposure to ivermectin. The majority of cases were reported from Cameroon (n = 176; 85%) with peaks in the incidence of SAE reporting in 1989–1991 and 1994–1995 when the program expanded to ivermectin-naïve populations. Fifty-five percent of the cases from Cameroon (i.e. 97 out of 176 cases) were encephalopathic and were reported from the central-southern region of the country; two-thirds of these cases were 'probable' or 'possible' cases of Loa loa encephalopathy temporally related to ivermectin treatment. Reporting bias may explain some but not all of the differences in SAE reporting between the 34 onchocerciasis-endemic countries that have, or have had, mass treatment programs. Further research is needed to understand the apparent clustering of encephalopathy cases in central-southern Cameroon since L. loa infection alone probably does not explain the increased incidence of this type of SAE from this region.  相似文献   
4.
In this study we aimed to evaluate serum insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3) and growth hormone (GH) levels in children with congenital heart disease (CHD) and to determine if these parameters have any relationship to the cyanosis, nutritional status and the left ventricular systolic function. This study is prospective-randomized study which conducted in 94 CHD patients (36 girls and 58 boys, aged between one 1-192 months, 19 cyanotic CHD and 75 acyanotic CHD) and age-sex matched 54 children (26 girls and 28 boys) with no CHD. In the study group, 37 out of the 94 CHD patients (39.4%) and 16 out of the 54 controls (29.6%) had malnutrition. The difference between the cyanotic and acyanotic patients in respect to malnutrition was significant (57.9% and 34.6%, p<0.05). Serum IGF-1 levels were lower (41.8+/-3.9 microg/L, 106.9+/-17.9 microg/L respectively, p<0.001) and GH levels were higher (6.43+/-0.9 ng/ml, 3.87+/-0.5 respectively, p<0.05) in CHD patient group than the controls. Serum IGF-1 levels were significantly lower in cyanotic CHD patients than the acyanotic patients (17.2+/-3.2 microg/L, 48.7.0+/-4.6 microg/L respectively, p<0.001) and serum IGF-1 levels were both lower in acyanotic and cyanotic CHD patients than the controls (p<0.001 for both). Serum IGF-1 and GH levels were similar between the well-nourished CHD patients and CHD patients with malnutrition (p>0.05). In total study group, the most effective factors on serum IGF-1 levels was presence of CHD (p<0.001), in CHD patients, the presence of cyanosis is the most effective factor on serum IGF-1 level, the presence of malnutrition is the most effective factor on serum IGFBP-3 levels (p<0.01). In the acyanotic, cyanotic, and the entire CHD patient groups, we find no correlations between the serum IGF-1, IGFBP-3 levels and left ventricular systolic function measurements. But serum GH levels were negatively correlated with diastolic left ventricular interseptum diameter, diastolic left ventricular mass and left ventricular end-diastolic volume measurements in CHD patients. In conclusion, we determined that the most important factor on serum IGF-1 levels is cyanosis. Reduced IGF1 levels and decreased left ventricular mass with an elevated GH levels in CHD patients and these findings are prominent in the cases with cyanosis and malnutrition. For this reason we believe that chronic hypoxia plays a significant role in the pathogenesis of malnutrition and also we believe that IGF-1 deficiency seen in CHD patients may be responsible in the etiology of the decrease in left ventricular mass independently from GH.  相似文献   
5.
3,5-Diaryl pyrazolines analogs were synthesized and evaluated for their monoamine oxidase (MAO) inhibitory activity. The compounds were found reversible and selective towards MAO-A with selectivity index in the magnitude of 103–105. The docking studies were carried out to gain further structural insights of the binding mode and possible interactions with the active site of MAO-A. Interestingly, the theoretical (Ki) values obtained by molecular docking studies were in congruence with their experimental (Ki) values.  相似文献   
6.
Amikacin (AK) has nephrotoxic side effects. AK-induced nephrotoxicity may be the consequence of oxidative stress and so anti-oxidant agents could be useful in reducing AK toxicity. Caffeic acid phenethyl ester (CAPE) was recently shown to have free radical scavenging ability and it reduces lipid peroxidation. For this purpose, the rats were distributed into three groups: (I) injected with vehicle (control); (II) injected (i.p.) with 1.2 g kg(-1) AK at a single dose; (III) injected (i.p.) with AK plus 10 micromol kg(-1) CAPE. Renal morphology was investigated by light microscopy. Tissue samples and trunk blood were also obtained to determine renal malondialdehyde (MDA), blood urea nitrogen (BUN) and creatinine (Cr) levels. MDA production was found to be higher in rats given AK than among control rats. CAPE administration before AK injection caused a significant decrease in MDA production. Morphological tubule damage in rats given AK was severe in the renal cortex, whereas in rats given AK plus CAPE, no histological changes occurred. It is concluded that CAPE could be useful for reducing the nephrotoxic effects of AK. Copyright (c) 2005 John Wiley & Sons, Ltd.  相似文献   
7.
There has been a new interest in using aldehyde dehydrogenase (ALDH) activity as one marker for stem cells since the Aldefluor flow cytometry-based assay has become available. Diethylaminobenzaldehyde (DEAB), used in the Aldeflour assay, has been considered a specific inhibitor for ALDH1A1 isoform. In this study, we explore the effects of human ALDH isoenzymes, ALDH1A2 and ALDH2, on drug resistance and proliferation, and the specificity of DEAB as an inhibitor. We also screened for the expression of 19 ALDH isoenzymes in K562 cells using TaqMan Low Density Array (TLDA). We used lentiviral vectors containing the full cDNA length of either ALDH2 or ALDH1A2 to over express the enzymes in K562 leukemia and H1299 lung cancer cell lines. Successful expression was measured by activity assay, Western blot, RT-PCR, and Aldefluor assay. Both cell lines, with either ALDH1A2 or ALDH2, exhibited higher cell proliferation rates, higher clonal efficiency, and increased drug resistance to 4-hydroperoxycyclophosphamide and doxorubicin. In order to study the specificity of known ALDH activity inhibitors, DEAB and disulfiram, we incubated each cell line with either inhibitor and measured the remaining ALDH enzymatic activity. Both inhibitors reduced ALDH activity of both isoenzymes by 65-90%. Furthermore, our TLDA results revealed that ALDH1, ALDH7, ALDH3 and ALDH8 are expressed in K562 cells. We conclude that DEAB is not a specific inhibitor for ALDH1A1 and that Aldefluor assay is not specific for ALDH1A1 activity. In addition, other ALDH isoenzymes seem to play a major role in the biology and drug resistance of various malignant cells.  相似文献   
8.
9.
Propolis is a multi-functional bee product rich in polyphenols. In this study, the inhibitory effect of Anatolian propolis against SARS-coronavirus-2 (SARS-CoV-2) was investigated in vitro and in silico. Raw and commercial propolis samples were used, and both samples were found to be rich in caffeic acid, p-coumaric acid, ferulic acid, t-cinnamic acid, hesperetin, chrysin, pinocembrin, and caffeic acid phenethyl ester (CAPE) at HPLC-UV analysis. Ethanolic propolis extracts (EPE) were used in the ELISA screening test against the spike S1 protein (SARS-CoV-2): ACE-2 interaction for in vitro study. The binding energy values of these polyphenols to the SARS-CoV-2 spike and ACE-2 protein were calculated separately with a molecular docking study using the AutoDock 4.2.6 program. In addition, the pharmacokinetics and drug-likeness properties of these eight polyphenols were calculated according to the SwissADME tool. The binding energy value of pinocembrin was highest in both receptors, followed by chrysin, CAPE, and hesperetin. Based on the in silico modeling and ADME (absorption, distribution, metabolism, and excretion) behaviors of the eight polyphenols, the compounds exhibited the potential ability to act effectively as novel drugs. The findings of both studies showed that propolis has a high inhibitory potential against the Covid-19 virus. However, further studies are now needed.  相似文献   
10.
The object was to determine the influence of dietary vitamin E, selenium and their combination on the fatty acid con-tent of erythrocytes, bone marrow and spleen lipids of Akkaraman lambs. After supplementation for 15 days, the amount of all fatty acids was slightly higher (p < 0·05) in the vitamin E as compared to the control group, whereas the amount of longer fatty acids was significantly higher (p < 0·01, p < 0·001) in the selenium and combination groups. On the thirtieth day, the amount of all fatty acids was slightly high (p < 0·5) in all the supplemented groups in comparison with the control group. In the bone marrow lipids, the amount of longer fatty acids was decreased (p < 0·05, p < 0·01, p < 0·001) in the vitamin E and combination groups as compared to the control. Although the amount of some fatty acids was high (p < 0·05, p < 0·01) in the selenium group compared to the control, linoleic (18:2), linolenic (18:3) and the polyunsaturated fatty acids (PUFA) were lower (p < 0·05, p < 0·001). In the spleen lipids, the amount of longer fatty acids was slightly decreased (p < 0·05) in the vitamin E group as compared with the control; however the amount of longer fatty acids was significantly higher (p < 0·05, p < 0·01) in the selenium and combination groups in comparison to the control group. Thus dietary supplementation with selenium was more effective than dietary vitamin E supplementation in altering the fatty acid content of the erythrocyte, bone marrow and spleen lipids. © 1997 John Wiley & Sons, Ltd.  相似文献   
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