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M A Akbarsha B Manivannan K S Hamid B Vijayan 《Indian journal of experimental biology》1990,28(5):421-426
Dry leaf powder of A. paniculata, when fed orally to male albino rats, at a dose level of 20 mg powder per day for 60 days, resulted in cessation of spermatogenesis, degenerative changes in the seminiferous tubules, regression of Leydig cells and regressive and/or degenerative changes in the epididymis, seminal vesicle, ventral prostate and coagulating gland. There was reduction in the weight and fluid content of the accessory glands. The treatment also resulted in accumulation of glycogen and cholesterol in the testis, and increased activities of lactate dehydrogenase in testis and alkaline phosphatase in testis and ventral prostate. The results suggest antispermatogenic and/or antiandrogenic effect of the plant. 相似文献
3.
Hamid Alinejad-Rokny Rassa Ghavami Modegh Hamid R. Rabiee Ehsan Ramezani Sarbandi Narges Rezaie Kin Tung Tam Alistair R. R. Forrest 《PLoS computational biology》2022,18(6)
Hi-C is a genome-wide chromosome conformation capture technology that detects interactions between pairs of genomic regions and exploits higher order chromatin structures. Conceptually Hi-C data counts interaction frequencies between every position in the genome and every other position. Biologically functional interactions are expected to occur more frequently than transient background and artefactual interactions. To identify biologically relevant interactions, several background models that take biases such as distance, GC content and mappability into account have been proposed. Here we introduce MaxHiC, a background correction tool that deals with these complex biases and robustly identifies statistically significant interactions in both Hi-C and capture Hi-C experiments. MaxHiC uses a negative binomial distribution model and a maximum likelihood technique to correct biases in both Hi-C and capture Hi-C libraries. We systematically benchmark MaxHiC against major Hi-C background correction tools including Hi-C significant interaction callers (SIC) and Hi-C loop callers using published Hi-C, capture Hi-C, and Micro-C datasets. Our results demonstrate that 1) Interacting regions identified by MaxHiC have significantly greater levels of overlap with known regulatory features (e.g. active chromatin histone marks, CTCF binding sites, DNase sensitivity) and also disease-associated genome-wide association SNPs than those identified by currently existing models, 2) the pairs of interacting regions are more likely to be linked by eQTL pairs and 3) more likely to link known regulatory features including known functional enhancer-promoter pairs validated by CRISPRi than any of the existing methods. We also demonstrate that interactions between different genomic region types have distinct distance distributions only revealed by MaxHiC. MaxHiC is publicly available as a python package for the analysis of Hi-C, capture Hi-C and Micro-C data. 相似文献
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Noor Khalidah Abdul Hamid Peace Onas Somdare Khadijah Abdullah Md Harashid Nurul Ain Othman Zulhisyam Abdul Kari Lee Seong Wei Mahmoud A.O. Dawood 《Saudi Journal of Biological Sciences》2022,29(5):3911
The purpose of this experiment was to examine the potential use of Carica papaya leaf extract as a supplement to promote growth and improve feed utilization in red hybrid tilapia. Five diets were formulated containing isolipidic (80 g/kg) and isonitrogenic (350 g/kg) levels. All feeds contained similar types and amounts of raw materials but differed in the inclusion of papaya leaf extract (0, 5, 10, 20 and 40 g/kg feed). The initial size of fish used was 2.3 ± 0.01 g. Each diet was performed in triplicate tanks, and the feeding period was 12 weeks. Fish fed diet containing 2% papaya leaf extract (PLE) had the highest final weight, 31.14 ± 1.47 g, followed by 1% PLE (27.27 ± 1.75 g). These two diets (1% and 2%) were also showed significant improvements of weight gain, SGR, and feed efficiency of the red hybrid tilapia (p < 0.05). However, papaya leaf extract did not affect the HSI, VSI, PER, digestive enzymes activity, blood composition, and survival rate. Supplementing the diets with papaya leaf extract lowered serum urea. Findings of this research suggest that adding papaya leaf extract to the diet of red hybrid tilapia improves growth and feed efficiency without adversely affecting blood parameters. Therefore, an inclusion level between 1% and 2% of the papaya leaf extract is recommended as a feed additive to promote red hybrid tilapia fry growth. 相似文献
5.
Hamid Hadi-Alijanvand Elizabeth A. Proctor Bahram Goliaei Nikolay V. Dokholyan Ali A. Moosavi-Movahedi 《PloS one》2012,7(10)
Prolyl hydroxylase domain 2 containing protein (PHD2) is a key protein in regulation of angiogenesis and metastasis. In normoxic condition, PHD2 triggers the degradation of hypoxia-inducible factor 1 (HIF-1α) that induces the expression of hypoxia response genes. Therefore the correct function of PHD2 would inhibit angiogenesis and consequent metastasis of tumor cells in normoxic condition. PHD2 mutations were reported in some common cancers. However, high levels of HIF-1α protein were observed even in normoxic metastatic tumors with normal expression of wild type PHD2. PHD2 malfunctions due to protein misfolding may be the underlying reason of metastasis and invasion in such cases. In this study, we scrutinize the unfolding pathways of the PHD2 catalytic domain’s possible species and demonstrate the properties of their unfolding states by computational approaches. Our study introduces the possibility of aggregation disaster for the prominent species of PHD2 during its partial unfolding. This may justify PHD2 inability to regulate HIF-1α level in some normoxic tumor types. 相似文献
6.
Hamid Reza Noori 《Journal of biological physics》2012,38(4):597-606
The phenomena related to brain function occur as the interplay of various modules at different spatial and temporal scales. Particularly, the integration of the dynamical behavior of cells within the complex brain topology reveals a heterogeneous multi-scale problem, which has, to date, mainly been addressed by methods of statistical physics such as mean-field approximations. In contrast, the present study introduces an abstract mathematical model of a deterministic nature that provides a robust integral transformation of the microscopic activities into macroscopic spatiotemporal patterns. The existence of the transformation operator is guaranteed by the convergence of a repetitive patching of the network domain with its fundamental domains that express the local topologies of the tissue. Depending on the choice of the local connectivity function, this framework represents a computationally efficient generalization of the classical Kirchhoff’s, Hebbian, and Hopfield’s approaches. The capabilities of this multi-scale method have been evaluated within the structure of the dorsal striatum of rats, a brain region with major involvement in motor and cognitive information processing. Numerical simulations suggest the formation of characteristic spatiotemporal patterns due to the activation of cholinergic interneurons. 相似文献
7.
Males of the predatory mirid bug Macrolophus caliginosus exploit plant volatiles induced by conspecifics as a sexual synomone 总被引:1,自引:0,他引:1
Hamid R. S. Moayeri Ahmad Ashouri Henrik F. Brødsgaard & Annie Enkegaard 《Entomologia Experimentalis et Applicata》2007,123(1):49-55
The olfactory responses of male and female Macrolophus caliginosus Wagner (Heteroptera: Miridae) adults towards volatiles from green bean plants previously exposed to feeding by conspecifics and to direct odours from conspecifics were tested in a Y-tube olfactometer. Female M. caliginosus did not respond to volatiles from plants exposed to mirid feeding or to odours emitted directly by adult mirids. In contrast, male mirid bugs were attracted both to volatiles from plants previously exposed to feeding by conspecific females and to odours emitted by conspecifics only with a marginally significant preference for the former. The gas chromatography-mass spectrometry analysis showed that mirid feeding induced the release of 11 additional compounds as compared to the volatiles emitted from clean plants. Three of these substances (5-ethyl-2(5H)-furanone, Z-3-hexenyl tiglate, and E,E-α-farnesene) were released only after feeding by females. Furthermore, 21 compounds were identified in volatiles emitted directly by mirids, 12 of which were unique to the mirids (i.e., not present in clean plants or plants previously exposed to mirid feeding). The results suggest that female-specific herbivore-induced plant volatiles play a role as mate-finding cues by the male mirids. The ecological implications of the findings are discussed, and the term ‘sexual synomone’ is introduced. 相似文献
8.
Javad Sajedianfard Zahra Behroozi Saeed Nazifi Hamid Rajaian 《International journal of peptide research and therapeutics》2013,19(2):93-98
The effect of oral administration of different doses of hydroalcoholic extract of silymarin on body weight, glucose concentration and indicators of oxidative stress superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and malondialdehyde (MDA) was investigated in the present study. Fifty adult male Wistar rats were used. The animals were divided into five groups and oral route of administration was used in control group (0.9 %, NaCl), control group patients (0.9 %, NaCl), diabetic group (100 mg/kg, silymarin), diabetic group (125 mg/kg, silymarin), diabetic group (250 mg/kg, silymarin) for 14 days with gavage. Diabetes was induced by a single injection of streptozotocin (45 mg/kg, i.p.). Before and 3 days after injection, and at 7 and 14 days of treatment, the fasting glucose level and weight were measured. At the end of 14 days, animals were anesthetized with ether and blood samples were taken by heart puncture and were analyzed for oxidative stress indicators. The results showed that hydroalcoholic extract of silymarin can increase the average body weight and decrease glucose and, at the end of 14 days, decrease MDA level and increase the level of antioxidant enzymes (SOD, GPX, CAT) in red blood cells in a dose-dependent manner (P < 0.05). In conclusion, the hydroalcoholic extract of silymarin has an overall beneficial effect on body weight, glucose level and oxidative stress. Therefore, silymarin may reduce oxidative stress via increasing antioxidant enzyme activity. 相似文献
9.
Shima Rajaei Saeed Karima Hessam Sepasi Tehrani Somayeh Shateri Somayeh Mahmoodi Baram Meisam Mahdavi Farzad Mokhtari Alimohammad Alimohammadi Abbas Tafakhori Abolfazl Amiri Vajiheh Aghamollaii Hamid Fatemi Masoumeh Rajabibazl Farzad Kobarfard Ali Gorji 《Journal of neurochemistry》2020,155(2):207-224
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