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591.
Design,synthesis, antinociceptive,and anti-inflammatory properties of thiazolopyrimidine derivatives
Ten 2-(substituted benzylidene)-7-(4-chlorophenyl)-5-(furan-2-yl)-2H-thiazolo[3,2-a]pyrimidin-3(7H)-one derivatives were synthesized and evaluated. A series of heterocyclic, 2-(substituted benzylidene)-7-(4-chlorophenyl)-5-(furan-2-yl)-2H-thiazolo[3,2-a]pyrimidin-3(7H)-one were synthesized by reaction of 7-(4-chloro phenyl)-5-(furan-2-yl)-2H-thiazolo[3,2-a]pyrimidin-3(7H)-one with appropriately substituted aldehydes in the presence of anhydrous sodium acetate and glacial acetic acid. The antinociceptive activity was evaluated by tail-flick technique, anti-inflammatory activity was evaluated by carrageenan-induced paw edema test and their ulcerogenicity index was determined. The para-substituted methyl, hydroxy, fluoro, chloro, bromo, and nitro derivatives showed significant antinociceptive and anti-inflammatory activities. The detailed synthesis, spectroscopic data, and pharmacological screening of the synthesized compounds were reported. 相似文献
592.
This work was undertaken to ascertain the impact of different fluence rates of ultraviolet-B (UV-B) radiation on two cyanobacterial biofertilizers, Phormidium foveolarum and Nostoc muscorum, growing under copper toxicity. Copper (2 and 5?µmol?L?1) and high UV-B fluence rate (UV-BH; 1.0?µmol?m?2?s?1) decreased the growth, pigment content, photosynthetic oxygen yield, phosphate uptake, and acid phosphatase activity in both the strains analyzed after 24 and 72?h of experiments, and combined exposure further enhanced the toxic effects. Respiration and alkaline phosphatase activities were stimulated appreciably. The damaging effect was shown on the order on pigments: phycocyanin?>?chlorophyll a?>?carotenoids, and on photosystems: whole chain photosynthetic reaction?>?photosystem II?>?photosystem I. Partial recovery in the photosystem II activity in the presence of artificial electron donors; diphenyl carbazide (DPC), hydroxylamine (NH2OH), and manganese chloride (MnCl2) pointed out the interruption of electron flow on the oxidation side of photosystem II. Unlike UV-BH, low UV-B fluence rate (UV-BL; 0.1?µmol?m?2?s?1), rather than causing damaging effect partially, alleviated the toxic effects of Cu. This study suggests that the cyanobacterium P. foveolarum is less sensitive against UV-BH and excess Cu (2 and 5?µmol?L?1), thus P. foveolarum may be used as a biofertilizer for sustainable agriculture. 相似文献
593.
The marine environment is continuously subjected to chemical pollution, which may exert a detrimental effect on aquatic organisms. Biodiversity of marine invertebrates has been proven to be difficult to assess accurately using traditional morphological methods. Major problems include dearth of characters in many taxa. Hence, it is necessary to assess the eco-health of this marine invertebrate using reliable measurements of environmental quality as required in the present study. With the backdrop of information, the Pudhumadam coastal area was surveyed for the diversity of ruined/washed out gastropods species. As a competitor for space with gastropods, these barnacles settle on the conus for its food and habitat. In our study, the occurrence of acorn barnacles was observed on gastropod shells. The pink adult and many white small barnacles were noted on the shells. If these barnacles increase their habitat this may lead to destruction of diversity of gastropods. 相似文献
594.
The river Kali has been one of the major recipients of industrial effluents in the Muzaffarnagar district of western Uttar Pradesh. The present studies revealed the occurrence and bioaccumulation of heavy metals (Cd, Cr, Pb, Zn, Mn) in riverine water, sediment, and muscles of two fish species, Heteropneustis fossilis and Puntius ticto. Data showed that the order of occurrence of heavy metals was Pb > Zn > Mn > Cr > Cd in river water, Mn > Zn > Pb > Cr > Cd in sediment, Zn > Mn > Cr > Cd > Pb in Puntius ticto and Cr > Zn > Mn > Cd > Pb in Heteropneustis fossilis. Results indicate that the concentrations of Cd, Pb, and Zn in river water, Pb, Zn, and Mn in sediment, Cd, Cr, Pb, and Zn concentration in muscles of Puntius ticto and Cr, Pb, and Zn concentration in in muscles of Heteropneustis fossilis are higher than the permissible standard limits. The presence of heavy metals contributed to toxicity in different organs of fish in River Kali. The bioaccumulation of heavy metals in different biotic organisms in river ecosystem may have adverse consequences on humans and livestock. 相似文献
595.
AbstractThe in vivo genotoxic potential of bisphenol A using the comet assay in mice and in human sperm cells in vitro without metabolizing enzymes was studied. Male mice were exposed by oral gavage to the following doses of bisphenol A (0 125, 250 and 500?mg/kg body weight). DNA damage was investigated in liver, kidney, testes, urinary bladder, colon and lungs cells. In testicular cells, a significant increase in DNA strand breaks was observed in the lowest, but not in the medium or highest dose groups. Histopathological investigation of the testicular samples did not show any treatment dose-related effects. No DNA strand breaks were observed in any of the other investigated tissues. In human sperm cells in vitro, bisphenol A did not induce DNA strand breaks. 相似文献
596.
Removal of p-chlorophenol (pCP) from synthetic aqueous solutions was studied through adsorption on a biosorbent developed from chitosan (CS) and sodium alginate (SA), the natural cationic and anionic polysaccharides, respectively. Chitosan-coated sodium alginate beads were prepared and treated with calcium chloride solution in order to improve the stability as well as hydrophobic character. The resulting beads (CS/CA) were characterized using FTIR spectra, scanning electron microscopy (SEM), and BET surface analysis. The efficiency of this biosorbent in removing pCP from aqueous medium was studied under batch equilibrium and dynamic column flow experimental conditions. The binding capacity of the biosorbent was studied as a function of initial pH, contact time, initial concentration of adsorbate and amount of biomass. The data were fitted to pseudo-first-order, pseudo-second-order, and Weber–Morris models and found that the adsorption process followed pseudo-first-order kinetics. Further, the equilibrium data were fitted to Freundlich, Langmiur, and Dubinin–Radushkevich (D–R) adsorption isotherms and the isotherm constants were evaluated for adsorption of pCP. The maximum monolayer adsorption capacity of CS/CA beads was found to be 127 mg g?1. Column flow results were used to generate breakthrough curves. The experimental results suggested that the chitosan–calcium alginate blended biosorbent was effective for the removal of pCP from aqueous medium. 相似文献
597.
Alok Kumar Vikram Bhardwaj Jitendra Nath Tiwari Devendra Kumar Patel Dhruv Sen Singh Ram Lakhan Singh 《毒物与环境化学》2013,95(2):373-381
Amyotrophic lateral sclerosis (ALS), a progressive disorder that usually runs a fatal course within 2–5 years of onset, is characterized by loss of motor neurons in the cortex, brain stem, and spinal cord. In this study mercury (Hg) concentrations were determined in blood samples of 40 ALS patients, of whom 24 ALS patients were from the Ganga plain region and their metal levels were found to be significantly higher. In contrast, Hg levels in the 16 ALS patients from non-Ganga plain regions whose levels were similar to those of the control subjects. Mercury in stream water samples and freshly deposited stream sediment were determined in the locations of patients’ native residences along the Ganga plain region and metal levels were found to be higher than the threshold guideline values for Hg in stream waters recommended by WHO. The geo-accumulation index in selected sites of freshly deposited stream sediment ranged from moderate to highly polluted. The high levels of Hg observed in ALS patients may potentially alter the redox status of neuronal cell components and induce cell-death pathways. 相似文献
598.
Manoj Kumar Pathak Mohammad Fareed Vipin Bihari Mudium Mohan Krishna Reddy Devendra Kumar Patel Neeraj Mathur 《毒物与环境化学》2013,95(1):188-196
In this study, nerve conduction, organochlorine (OC) pesticide residues in blood and cholinesterase activity levels of pesticide sprayers employed in mango plantations at Lucknow, North India, were determined. Fifty-two sprayers from mango plantations who regularly spray mixture of pesticides like organophosphates (OP), OCs, and carbamates were considered as exposed group. Eighteen subjects with similar socio-economic status of exposed group, who do not handle pesticides, were selected as controls. Questionnaire-based interviews related to personal and occupational histories of the study subjects were carried out. Sprayers did not use any personal protective equipment during pesticide handling. The blood-pesticide analyses of sprayers show higher mean values of hexachlorohexane (HCH), γ-HCH, δ-HCH, total HCH, op-DDT compared with the controls. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activites were significantly reduced among sprayers. Risk of motor nerve conduction deficits was observed in sprayers with low AChE activity. Negative correlation of motor and sensory nerve conduction deficits was observed with the duration of exposure and age among sprayers. The study demonstrated that the prolonged exposure to mixture of pesticides, ergonomic factors, decline in cholinesterase activity may lead to nerve conduction dysfunction. The findings suggest the need for controlled use of pesticides in the plantation and indicated the need for training and implementation of hygiene practices like proper usage of personal protective equipments. 相似文献
599.
Chetan Kumar 《国际发展与全球生态学杂志》2013,20(5):532-542
The participatory approach in management of forests is now well established in forest policies of many developing countries. Incentives for different groups to participate have been argued by many to be desirable characteristics to promote participation. A key challenge for government and donor agencies is to develop better understanding of the incentives for different groups to be able to achieve and sustain their participation. Based on a case study of a joint forest management (JFM) programme in the northern state of Haryana in India, this paper highlights the relevance of understanding people's perception of the incentives. It specifically examines three hypotheses related to perceptions of villagers about incentives offered under the JFM programme and relates them to their participation in joint management. It concludes that a better understanding is likely to help in improving project implementation at the local level and the design of participatory forest management programmes more generally. 相似文献
600.
Subhash Chand Sharwan Singh Shinoj Parappurathu S. Dam Roy Anjani Kumar 《国际发展与全球生态学杂志》2013,20(4):335-345
In the past few decades, the tourism sector has emerged as a significant economic activity in island nations, particularly in tropical regions. However, most of the tropical islands face similar constraints, viz., threat to natural resources, chances of biopiracy, impact of climate change, population pressure and unsystematic tourist management. Ecotourism, as a concept, envisages promoting tourism with due regard to natural environment and ecological sanctity of the destination. Archipelago of Andaman and Nicobar (A&N) Islands is one of picturesque geographical creation in the Bay of Bengal, India, in tropical region and is an emerging tourist destination. It was observed that around 2.2 lakhs national and international tourists visit the A&N Islands annually. With tourism sector as an integral component, the service sector with share of 56% in gross state domestic product dominates the island economy. An analysis based on primary survey from various stakeholders associated with the sector revealed that factors such as economy in travel and boarding, availability of tourist facilities and comfort, safety, etc. were major factors that determined the choice of the tourists that visited the islands. The weights given by the tourists to the natural sites in A&N Islands revealed that the landscape topped list with 91.6% score by the visitors followed by beaches (91.3%), scenery (86.5%), reserved forests (84.6%), limestone caves (66.3%) and coral sights (65.8%). Coral sites were given weight of 65.8% of tourists, cultural and historical tourism products 85.4% for the natural history. Similarly, historical sites (83.7%), museums (78.6%) and heritage sites (72.8%) were also among top cites attraction. Recent initiatives by the Andaman administration gives due to care to sustainably develop the tourism infrastructure of the islands to harness the potential of eco-friendly tourism in this picturesque tourist haven. 相似文献