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991.
《Saudi Journal of Biological Sciences》2022,29(5):3899-3910
Trichophyton rubrum is one of the major disease causing pathogens in human; mainly it causes tinea pedis, tinea cruris and tinea corporis. Cytochrome P450 which considered to be an important protein that can impact ergosterol biosynthesis pathway. B. aegyptiaca is rich source of secondary metabolites with tremendous medicinal values and it has sweet pulp, leaves with spine, strong seed and oily kernel. The epicarp of the fruit was taken for this study to inhibit T. rubrum using in vitro and in silico techniques. The epicarp portion was extracted using various solvents and water. The anti-dermatophytic activity on T. rubrum of these extracts was assessed utilizing poison plate technique with 5 individual concentrations. The fractioned chloroform extract of epicarp had fully inhibited the growth of T. rubrum at 3 mg/ml. Further, the chloroform extract was subjected to LC-MS analysis, in total, 40 compounds were elucidated. Then, the derived compounds were included for predicting ADMETox properties using Qikprop module. From the analysis 40 compounds were identified to be eligible for docking process. Then the desirable compounds, drug Ketoconazole were subjected to docking analysis using Glide module of Schrödinger. It shows that Platyphylloside has better docking result than other compounds and drug Ketoconazole. Further, MD simulation was carried out for Ketoconazole-Cyp450 and Platyphylloside-CYP450 complexes using Desmond, Schrödinger. MD simulation study also confirmed that the Platyphylloside-CYP450 complex more stable. This study suggests that Platyphylloside may act as potential inhibitor and it could be further subjected to experimental analysis to inhibit the T. rubrum growth. 相似文献
992.
《Saudi Journal of Biological Sciences》2022,29(8):103311
Depression is a complex psychiatric disturbance involving many environmental, genetic, and epigenetic factors. Until now, genetic, and non-genetic studies are still on the way to understanding the complex mechanism of this disease, and there are still many questions that have not yet been answered. Depression includes a large spectrum of heterogeneous symptoms correlated to the deficit of a range of psychological, cognitive, and emotional processes, and it affects various age groups. It is classified into several types according to the severity of symptoms, time of occurrence, and time. Following the World Health Organization (WHO), depression attacks near 350 million persons globally. Several factors overlap in causing depression, including genetic and epigenetic factors, environmental conditions, various stresses, lack of some nutrients to which people are exposed, and excessive stress and abuse in childhood. This study included conducting surveys on depression and new treatment trends based on epigenetic factors associated with the occurrence of the disease. Epigenetic factors provide a completely novel dimension to therapeutic approaches as most diseases are not monogenic, and it is likely that the environment has a significant contribution. Epigenetic inheritance is included in many mental and psychiatric disorders such as depression. In general, epigenetic modifications could be summarized in 3 major points: DNA methylation, histone modification, and non-mediated regulation of RNA (ncRNA). This study also describes some genes associated with one of the depressive disorders using bioinformatics tools and gene bank and had the genes: SLC6A4, COMT, TPH2, FKBP5, MDD1, HTR2A, and MDD2. As in this study, the awareness of Saudi society about depression and its genetic and non-genetic causes was estimated. The results showed that an encouraging percentage of more than half of the research sample possessed correct information about this disorder. 相似文献
993.
Sharon L. Deem Fiona Maisels Richard G. Robbins 《European Journal of Wildlife Research》2005,51(1):60-62
A field necropsy was performed on a recently dead adult forest buffalo, Syncerus caffer nanus, found in the Nouabalé-Ndoki National Park, Republic of Congo. Based on the gross and histological lesions, the cause of death was determined to be conspecific fighting. Ectoparasites collected from this forest buffalo were Amblyomma sp. (larvae) and Rhipicephalus ziemanni Neumann. Endoparasites collected included a paramphistomid trematode, Carmyerius gregarius, and oocysts of Eimeria spp., paramphistomid eggs (presumably from C. gregarius), metastrongylid lungworm larvae, and strongylid eggs. Parasitic findings from this forest buffalo were compared to previous reports from savanna and forest buffalo. 相似文献
994.
Bjørn P. Kaltenborn Julius W. Nyahongo K. Margrethe Tingstad 《European Journal of Wildlife Research》2005,51(4):213-222
In many parts of Africa, illegal hunting is considered the most pressing issue in protected areas. Poaching has remained a persistent problem through the 50 year long history of Serengeti National Park. Around 2 million people live along the borders of the park. Poverty is widespread, and the population is increasing rapidly. In this paper we examine the local perceptions of importance and reasons for hunting, gender differences and opinions about mitigating measures among villagers around Serengetis Western Corridor. The data were collected through interviewing 590 persons in eight villages close to the borders of the park. Hunting is driven by the need to not only increase food supply and cash income, but also fulfil cultural and social needs. We also identified a proactive attitude in the rural communities towards reducing illegal hunting and more constructive relationships with the management authorities of the national park. The role of hunting in community life extends beyond the immediate poverty issue, and should be seen as an element in the larger development agenda of rural Tanzania and the quest for models for sustainable wildlife management. 相似文献
995.
The role of ammonia volatilization in controlling the natural 15N abundance of a grazed grassland 总被引:1,自引:0,他引:1
Although the variation in natural 15N abundance in plants and soils is well characterized, mechanisms controlling N isotopic composition of organic matter are still poorly understood. The primary goal of this study was to examine the role of NH3 volatilization from ungulate urine patches in determining 15N abundance in grassland plants and soil in Yellowstone National Park. We additionally used isotopic measurements to explore the pathways that plants in urine patches take up N. Plant, soil, and volatilized NH315N were measured on grassland plots for 10 days following the addition of simulated urine. Simulated urine increased 15N of roots and soil and reduced 15N of shoots. Soil enrichment was due to the volatilization of isotopically light NH3. Acid-trapped NH315N increased from –28 (day 1) to –0.3 (day 10), and was lighter than the original urea-N added (1.2). A mass balance analysis of urea-derived N assimilated by plants indicated that most of the N taken up by plants was in the form of ammonium through roots. However, isotope data also showed that shoots directly absorbed 15N – depleted NH3-N that was volatilized from simulated urine patches. These results indicate that NH3 volatilization from urine patches enriches grassland soil with 15N and shoots are a sink for volatilized NH3, which likely leads to accelerated cycling of excreted N back to herbivores. 相似文献
996.
Fine-scale variation in corticolous bryophyte communities was examined on the lower trunk of Antarctic beech (Nothofagus moorei) trees within microphyll fern forests of south-east Queensland. Analysis of the variation revealed that the composition and structure of the community altered with both the height above ground level and the direction of exposure. Patterns of distribution were thought to primarily reflect changes in the moisture availability on and around the basal trunk of Nothofagus moorei trees and the degree of desiccation tolerance exhibited by the various taxa. 相似文献
997.
998.
Nichole?N.?BargerEmail author Jayne?Belnap Dennis?S.?Ojima Arvin?Mosier 《Biogeochemistry》2005,75(3):373-391
In this study, we examined N gas loss as nitric oxide (NO) from N-fixing biologically crusted soils in Canyonlands National
Park, Utah. We hypothesized that NO gas loss would increase with increasing N fixation potential of the biologically crusted
soil. NO fluxes were measured from biologically crusted soils with three levels of N fixation potential (Scytonema-Nostoc-Collema spp. (dark)>Scytonema-Nostoc-Microcoleus spp. (medium)>Microcoleus spp. (light)) from soil cores and field chambers. In both cores and field chambers there was a significant effect of crust
type on NO fluxes, but this was highly dependent on season. NO fluxes from field chambers increased with increasing N fixation
potential of the biologically crusted soils (dark>medium>light) in the summer months, with no differences in the spring and
autumn. Soil chlorophyllasis Type a content (an index of N fixation potential), percent N, and temperature explained 40% of the variability in NO fluxes from
our field sites. Estimates of annual NO loss from dark and light crusts was 0.04-0.16 and 0.02-0.11-N/ha/year. Overall, NO
gas loss accounts for approximately 3-7% of the N inputs via N fixation in dark and light biologically crusted soils. Land
use practices have drastically altered biological soil crusts communities over the past century. Livestock grazing and intensive
recreational use of public lands has resulted in a large scale conversion of dark cyanolichen crusts to light cyanobacterial
crusts. As a result, changes in biologically crusted soils in arid and semi-arid regions of the western US may subsequently
impact regional NO loss. 相似文献
999.
Hominins, sedges, and termites: new carbon isotope data from the Sterkfontein valley and Kruger National Park 总被引:3,自引:0,他引:3
Sponheimer M Lee-Thorp J de Ruiter D Codron D Codron J Baugh AT Thackeray F 《Journal of human evolution》2005,48(3):301-312
Stable carbon isotope analyses have shown that South African australopiths did not have exclusively frugivorous diets, but also consumed significant quantities of C4 foods such as grasses, sedges, or animals that ate these foods. Yet, these studies have had significant limitations. For example, hominin sample sizes were relatively small, leading some to question the veracity of the claim for australopith C4 consumption. In addition, it has been difficult to determine which C4 resources were actually utilized, which is at least partially due to a lack of stable isotope data on some purported australopith foods. Here we begin to address these lacunae by presenting carbon isotope data for 14 new hominin specimens, as well as for two potential C4 foods (termites and sedges). The new data confirm that non-C3 foods were heavily utilized by australopiths, making up about 40% and 35% of Australopithecus and Paranthropus diets respectively. Most termites in the savanna-woodland biome of the Kruger National Park, South Africa, have intermediate carbon isotope compositions indicating mixed C3/C4 diets. Only 28% of the sedges in Kruger were C4, and few if any had well-developed rhizomes and tubers that make some sedges attractive foods. We conclude that although termites and sedges might have contributed to the C4 signal in South African australopiths, other C4 foods were also important. Lastly, we suggest that the consumption of C4 foods is a fundamental hominin trait that, along with bipedalism, allowed australopiths to pioneer increasingly open and seasonal environments. 相似文献
1000.
Santosh?Kumar?SarkarEmail author Asokkumar?Bhattacharya Sankar?Giri Badal?Bhattacharya Dipak?Sarkar Dulal?Chandra?Nayak Asish?Kumar?Chattopadhaya 《Wetlands Ecology and Management》2005,13(1):55-67
Annelida constitute a dominant functional component in soft-bottom macrobenthic communities and reveal a wide range of adaptability to different marine and coastal habitats. Analyses in different polychaete assemblages and their responses to habitat conditions reflect the biological effects of marine pollution and habitat disturbance. The present study is designed to study colonization and community structure of polychaetes in two ecologically distinct locations of the Sundarban Biosphere Reserve on the northeast coast of India. Polychaete assemblages are characteristically different at the two sites in the extreme northern (Ghusighata) and southern (Gangasagar) portions of the Biosphere Reserve. Levels of heavy metals in polychaete body tissues also reveal interspecific and regional variations. The predominant polychaete fauna exhibited a distinct and unique assemblage of two types: (i) Mastobranchus indicus – Dendronereides heteropoda in the sewage-fed substratum at Ghusighata and (ii) Lumbrinereis notocirrata – Ganganereis sootai – Glycera tesselata at Gangasagar at the mouth of the Hugli estuary where chronic anthropogenic stress and contamination with agricultural and industrial effluents occur. The faunistic composition of polychaetes and their potential for the accumulation of heavy metals from the ambient medium are distinctly different. The study demonstrates that textural composition of the sediments, together with hydrodynamic and geotechnical properties, seem to have the greatest control to quantify the differences of the polychaete community in the two study stations. An in-depth comparative study of polychaete community structure at multiple spatial scales is strongly recommended for future environmental impact assessment in this fragile environment. 相似文献