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871.
The effects of estrus synchronization with prostaglandin F (PGF) and Controlled Internal Drug Release Device (CIDR) on ensuing antral follicular development were documented and compared to natural estrous cycles of non-seasonal tropical goats. Two to six follicular waves were observed, with the three-follicular wave pattern being most frequently observed (58%), followed by four follicular waves (31.6%) per estrous cycle. There were no significant differences (p > 0.05) between the PGF- or CIDR-synchronized and natural estrous cycles nor between the synchronized and subsequent non-synchronized cycles in terms of the time of ovulation, the duration of inter-ovulatory intervals, daily numbers of antral follicles ≥3 mm in diameter, and the number of follicular waves per cycle in the goats of the present study.  相似文献   
872.
Diabetic nephropathy is a major cause of morbidity and mortality in diabetic patients. To prevent the development of this disease and to improve advanced kidney injury, effective therapies directed toward the key molecular target are required. In this paper, the efficacy of fenugreek to restore the kidney function of diabetic rats via its antioxidant and anti-inflammatory activities has been studied. Novel data showing the efficacy of fenugreek to attenuate progression of diabetic nephropathy and production of interleukin-6 (IL-6) in rats compared with a diabetic untreated group were obtained. Rats were classified into five groups; control, diabetic untreated, and three diabetic groups treated with fenugreek, rosiglitazone, and metformin. Treatment with fenugreek has been continued for 12 weeks. Fenugreek was found to significantly reduce the high levels of glucose, urea, creatinine, sodium, potassium, and IL-6 in serum compared with the diabetic untreated group. In addition, levels of malondialdehyde and IL-6 in the kidney homogenate were significantly reduced as a result of the fenugreek treatment compared with the diabetic untreated group. Moreover, concentration of GSH and the activity of both superoxide dismutase and catalase were considerably increased in the diabetic treated groups compared with the diabetic untreated group. Furthermore, glomerular mesangial expansion was reduced in the treated animal groups. These findings suggest a therapeutic potential of fenugreek against diabetic nephropathy, explain its antioxidative/anti-inflammatory properties and provide a direction for future research.  相似文献   
873.
The changes in crude protein, free amino acids, amino acid composition, protein solubility, protein fractionation and protein digestibility after germination of sorghum were investigated. Sorghum varieties (Dorado, Shandaweel-6, Giza-15) were soaked for 20 h followed by germination for 72 h; the results revealed that crude protein and free amino acids in raw sorghum varieties ranged from 10.62 to 12.46% and 0.66 to 1.03 mg/g, respectively. Shandaweel-6 was the highest variety in crude protein and free amino acids content. After germination, crude protein was decreased and free amino acids were increased. There was an increase in content of valine and phenylalanine amino acids after germination. On the other hand, there was a decrease in most of amino acids after germination. After germination protein solubility was significantly increased. Regarding protein fractions, there was an increase in albumin, globulin and kafirin proteins and a decrease in cross linked kafirin and cross linked glutelin after germination.  相似文献   
874.

Background

Home range is defined as the extent and location of the area covered annually by a wild animal in its natural habitat. Studies of African and Indian elephants in landscapes of largely open habitats have indicated that the sizes of the home range are determined not only by the food supplies and seasonal changes, but also by numerous other factors including availability of water sources, habitat loss and the existence of man-made barriers. The home range size for the Bornean elephant had never been investigated before.

Methodology/Principal Findings

The first satellite tracking program to investigate the movement of wild Bornean elephants in Sabah was initiated in 2005. Five adult female elephants were immobilized and neck collars were fitted with tracking devices. The sizes of their home range and movement patterns were determined using location data gathered from a satellite tracking system and analyzed by using the Minimum Convex Polygon and Harmonic Mean methods. Home range size was estimated to be 250 to 400 km2 in a non-fragmented forest and 600 km2 in a fragmented forest. The ranging behavior was influenced by the size of the natural forest habitat and the availability of permanent water sources. The movement pattern was influenced by human disturbance and the need to move from one feeding site to another.

Conclusions/Significance

Home range and movement rate were influenced by the degree of habitat fragmentation. Once habitat was cleared or converted, the availability of food plants and water sources were reduced, forcing the elephants to travel to adjacent forest areas. Therefore movement rate in fragmented forest was higher than in the non-fragmented forest. Finally, in fragmented habitat human and elephant conflict occurrences were likely to be higher, due to increased movement bringing elephants into contact more often with humans.  相似文献   
875.
Of 24 fungi belonging to more than five genera isolated from tubers of rotten Helianthus tuberosus, 11-inulinolytic active isolates were able to develop halo zones around their fungal colonies, indicating inulinase activity. Alternaria, Aspergillus, Fusarium, Pencillium and Trichoderma were the most common inulinolytic genera, representing more than 90?% of the total positive inulinolytic fungi. Aspergillus tamarii and Pencillium citrinum quantitatively recorded better growth (5.5 and 4.7?mg?ml?1) and inulinase production (21.53 and 20.15?U?ml?1) in submerged culture. The enzyme preparation showed also invertase activity. Aspergillus tamarii, as the most potent producer of inulinase, was identified using the Inter Transcribed Spacer marker. The sequence comparisons showed that our molecularly identified strain (GU295949) is related more closely to A. tamarii strains of the gene bank. Statistical screening using the fractional factorial Plackett-Burman design with 12 run was applied for screening ten variables, the low levels of pH (4.8), inoculum size (103 spore?g?1), NH4NO3 (1.0?mg?g?1) and MgSO4 (0.12?mg?g?1), were the most significant variables on A. tamarii inulinase production. The high inulinase/invertase ratio (1.841?C4.293) classified the enzyme preparation as inulinases, which can be used efficiently in production of fructose syrup from tubers of H. tuberosus.  相似文献   
876.
Loss and disproportionate gain of body weight often seen respectively in smokers and quitters are believed to be due to disrupted energy homeostasis induced by nicotine, the major constituent of cigarette smoke. Energy homeostasis is suggested to be regulated by the coordinated actions of peripheral adipose tissue derived leptin and the brain hypothalamic orexigenic neuropeptide Y (NPY). While the studies probing the role of leptin and NPY in weight modulating effect of nicotine have so far been inconsistent and based largely on animal systems, there is a paucity of data involving human subjects. Here we measured the plasma levels of orexigenic neuropeptide Y (NPY) and leptin in 35 non-smokers and 31 cigarette smokers before and three months after smoking cessation. Compared to non-smokers, smokers were leaner and had reduced NPY and leptin levels. Smoking cessation resulted in a significant weight gain and increased waist circumference accompanied by increased leptin and NPY levels. NPY levels were significantly correlated with body weight (r=0.43, p<0.05), BMI (r=0.41, p<0.05), and waist circumference (r=0.37, p<0.05), while leptin correlated with BMI (r=0.42, p<0.05) and waist circumference (r=0.39, p<0.05). Association of leptin with smoking status, but not that of NPY, was lost after controlling for anthropometric parameters. Weight modulating effect of cigarette smoke may thus involve its direct action on NPY, independent of leptin. Altered leptin levels in smokers and quitters may merely reflect changes in body weight or precisely fat mass.  相似文献   
877.
miR‐122 and miR‐192 were investigated as indicators of toxic liver injury caused by acetaminophen, but their role in idiosyncratic toxic liver injury remains controversial. So, this work aimed to assess and compare the expressions of miR‐122 and miR‐192 in two different types of toxic liver injury (intrinsic [acetaminophen] and idiosyncratic [diclofenac]). Forty male adult Wistar albino rats were divided into equal five groups, in which serum liver enzymes; microRNAs (miRNAs) expressions (miR‐122 and miR‐192) and histopathological findings were studied. The present study showed that (1) miR‐122 and miR‐192 are good serum biomarkers of toxic liver injury whatever its etiology, as their serum levels exhibited a significantly earlier increase and earlier return to normal baseline levels as compared to serum aminotransferase levels; (2) miR‐122 is more specific than miR‐192; and (3) both serum levels of miR‐122 and miR‐192 showed non‐significant differences in relation to the type of toxic liver injury.  相似文献   
878.
The genomic diversity and relationship among 56 Bacillus thuringiensis and Bacillus cereus type strains were investigated by multi-REP-PCR fingerprinting consisting of three PCR reactions targeting the enterobacterial ERIC1 and ERIC2 and the streptococcal BOXA1R consensus sequences. A total of 113 polymorphic bands were generated in the REP-PCR profiles that allowed tracing of a single dendrogram with three major groups. Bacillus cereus strains clustered together in the A and B groups. Most of the B. thuringiensis strains clustered in group C, which included groups of serovars with a within-group similarity higher than 40% as follows: darmstadiensis, israelensis, and morrisoni; aizawai, kenyae, pakistani, and thompsoni; canadensis, entomocidus, galleriae, kurstaki, and tolworthi; alesti, dendrolimus, and kurstaki; and finitimus, sotto, and thuringiensis. Multi-REP-PCR fingerprinting clustered B. thuringiensis serovars in agreement with previously developed multilocus sequence typing schemes, indicating that it represents a rapid shortcut for addressing the genetic relationship of unknown strains with the major known serovars.  相似文献   
879.
The non-pathogenic endophytic fungus, Fusarium oxysporum strain 162, originally isolated from the endorhiza of tomato roots, reduces damage caused by Meloidogyne incognita, by inhibiting juvenile penetration of and development in the root. However, little is known about the mode of action of this endophyte fungus against the nematode. This study aimed at investigating how the endophyte affects nematode motility and survival and if induced resistance plays a role in the relationship. In a previous study, F. oxysporum strain 162 decreased nematode penetration of tomato up to 60%. In experiments using a split-root chamber to test for induced resistance, nematode penetration, number of galls, and number of egg masses were investigated 2 and 5 weeks after nematode inoculation. Split-root plants treated with F. oxysporum strain 162 showed 26-45% less nematode penetration, 21-36% less galls and a 22-26% reduction in the number of egg masses in the roots not directly inoculated with the fungus when compared to untreated control plants in repeated tests. In conclusion, inoculation of tomato plants with the non-pathogenic fungal endophyte F. oxysporum strain 162 resulted in a signficant reduction of nematode infection, which was in part due to induced resistance in the first 2-3 weeks after fungal inoculation.  相似文献   
880.
MicroRNA (miRNA)-21 and miRNA-155 are important regulators of gene expression of different immunological molecules. This study aimed to investigate the role of miRNA-21 and miRNA-155 as biomarkers in asthma by comparing their serum expression levels in asthmatic patients to those in healthy controls and correlating their levels with serum IL-4. The expression levels of miRNA-21 and miRNA-155 were evaluated by quantitative RT-PCR. Serum levels of IL-4 were determined using ELISA. Asthmatic patients showed significantly higher serum miRNA-21 and miRNA-155 expression levels compared to controls. A statistically significant positive correlation between the expression levels of miRNA-21 and IL-4 serum levels in asthmatic patients was detected. Nonetheless, no correlation was detected between miRNA-155 expression and each of IL-4 and miRNA-21. A receiver operating characteristic curve analysis showed that at a cut-off value of 1.37, the sensitivity of miRNA-21 as an asthma biomarker was 100% and the specificity was 95%. At a cut-off value of 1.96, the sensitivity of miRNA-155 as an asthma biomarker was 100% and the specificity was 100%. It can be concluded that miRNA-21 and miRNA-155 are potential non-invasive biomarkers in the diagnosis of eosinophilic asthma and its response to therapy.  相似文献   
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