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91.
Sohail Ejaz Khaleeq Anwar Robina Taj Muhammad Ashraf 《Central European Journal of Biology》2014,9(3):298-308
Angiogenesis is the formation of new blood vessels from the existing blood vessels and is involved in both physiological and pathological events. Pathological angiogenesis provokes in several important diseases as in inflammatory diseases, ischemic conditions, diabetic neuropathy and cancer. The discovery of new drugs from phyto-chemicals has a long history and anti-angiogenic agents from plant sources provide a platform for the development of phyto-medicines to treat/control pathological angiogenesis. The current project was designed to determine the efficacy of different concentrations of aqueous extract from Opuntia dillenii (OD) on angiogenesis by employing chicken chorioallantoic membrane (CAM) assay. Computer based 3D image probing was utilized to quantify anti-angiogenic effects of OD extract. Extremely aggravated dose dependent anti-angiogenic response was recorded in all groups treated with OD extract with significant reduction (P<0.01) in total area, diameter of the primary, secondary, tertiary blood vessels and capillary plexuses. Analysis of 3D parameters of OD treated CAMs revealed deteriorated angular spectrum and reduction in the height of Abbott curves. In addition, histological data revealed thinning of ectodermal layer and damaged extracellular matrix. The results spotlight that OD extract possess considerable anti-angiogenic potential and further characterization/isolation of diverse phyto-chemicals would turn up with the discovery of novel phyto-agents to control/mitigate pathological angiogenesis. 相似文献
92.
Background
Isodon rugosus is used traditionally in the management of hypertension, rheumatism, tooth-ache and pyrexia. Present study was arranged to investigate I. rugosus for phytoconstituents, phytotoxic and cytotoxic activities to explore its toxicological, pharmacological potentials and to rationalize its ethnomedicinal uses. Briefly, qualitative phytochemical analysis of the plant extracts were carried out for the existence of alkaloids, flavonoids, saponins, oils, glycosides, anthraquinones, terpenoids, sterols and tannins. Plant crude methanolic extract (Ir.Cr), its subsequent fractions; n-hexane (Ir.Hex), chloroform (Ir.Chf), ethyl acetate (Ir.EtAc), aqueous (Ir.Aq) and saponins (Ir.Sp) in different concentrations were tested for phytotoxic and cytotoxic activities using radish seeds and brine shrimps (Artemia salina) respectively. The phytotoxic activity was determined by percent root length inhibition (RLI) and percent seeds germination inhibition (SGI) while the cytotoxicity was obtained with percent lethality of the brine shrimps.Results
Ir.Cr was tested positive for the presence of alkaloids, glycosides, flavonoids, oils, terpenoids, saponins, tannins and anthraquinones. Among different fractions Ir.Sp, Ir.Chf, Ir.EtAc, and Ir.Cr were most effective causing 93.55, 89.32, 81.32 and 58.68% inhibition of seeds in phytotoxicity assay, with IC50 values of 0.1, 0.1, 0.1 and 52 μg/ml respectively. Similarly, among all the tested samples, Ir.Sp exhibited the highest phytotoxic effect causing 91.33% root length inhibition with IC50 of 0.1 μg/ml. Ir.Sp and Ir.Chf were most effective against brine shrimps showing 92.23 and 76.67% lethality with LC50 values of 10 and 12 μg/ml respectively.Conclusions
It may be inferred from the current investigations that I. rugosus contains different secondary metabolites and is a potential source for the isolation of natural anticancer and herbicidal drug molecules. Different fractions exhibited phytotoxic and cytotoxic activities, thus providing pharmacological basis for ethnomedicinal uses of this plant. 相似文献93.
Present study provides an easy and efficient protocol for large scale clonal propagation of Coleus forskohlii, a threatened medicinal plant of commercial importance. Basal leaf lamina excised from upper three nodes of shoot was used as explant and its size, position, orientation and season of collection were initially optimized to select the most responsive explant condition. Enhanced shoot production and proliferation has been achieved on medium containing 2 μM BA + 0.1 μM NAA wherein, a highest number of 35 shoots/explant were produced. The regenerated shoots of varied length (3–5 cm) were transferred to root induction medium comprising of IBA, NAA and IAA (1–5 μM) in half-strength MS medium to determine the most suitable shoot length for proper root induction. Rooted plantlets were acclimatized in field conditions after proper hardening. Histological analysis was also carried out to confirm the nature of origin of shoot buds from leaf explants. 相似文献
94.
Anwar Rayan 《Journal of molecular modeling》2010,16(2):183-191
Human G-protein coupled receptors (hGPCRs) comprise the most prominent family of validated drug targets. More than 50% of
approved drugs reveal their therapeutic effects by targeting this family. Accurate models would greatly facilitate the process
of drug discovery and development. However, 3-D structure prediction of GPCRs remains a challenge due to limited availability
of resolved structure. The X-ray structures have been solved for only four such proteins. The identity between hGPCRs and
the potential templates is mostly less than 30%, well below the level at which sequence alignment can be done regularly. In
this study, we analyze a large database of human G-protein coupled receptors that are members of family A in order to optimize
usage of the available crystal structures for molecular modeling of hGPCRs. On the basis of our findings in this study, we
propose to regard specific parts from the trans-membrane domains of the reference receptor helices as appropriate template for constructing models of other GPCRs, while other
residues require other techniques for their remodeling and refinement. The proposed hypothesis in the current study has been
tested by modeling human β2-adrenergic receptor based on crystal structures of bovine rhodopsin (1F88) and human A2A adenosine
receptor (3EML). The results have shown some improvement in the quality of the predicted models compared to Modeller software. 相似文献
95.
Faisal Imam Manju Sharma Naif Obaid Al-Harbi Mohammad Rashid Khan Wajhul Qamar Muzaffar Iqbal Mohammad Daud Ali Nemat Ali Md. Khalid Anwar 《Saudi Journal of Biological Sciences》2021,28(4):2041-2048
First-line antituberculosis (anti-TB) compounds have been considered as proven components of the Directly Observed Treatment-Short course (DOTS). Drug therapy against tuberculosis has been categorized as I, II, or III following the Revised National Tuberculosis Control Program guidelines. Anti-TB are drugs are quite common and show limited adverse effects. However, first-line anti-TB compounds mediated DOTS therapy and were found with several complications. Thus, those drugs have been discontinued. Therefore, the present study was designed to find out the possible impact of socioeconomic, income, and educational status on the adverse effects of drugs and their therapeutic episodes in patients targeted with a combination of tuberculosis intervention. This study found that an increased incidence of tuberculosis was found in patients who have finished high school, contributing to a high percentage of adverse effects. Notably, adverse events were shown maximally in poor patients compared with rich- or high-income patients. On the contrary, a high prevalence of adverse events was shown to be increased in partially skilled workers compared with full-skilled workers. Consequently, adversely considerable events were implicated to be raised in patients associated with minimal socioeconomic class. Such interesting factors would help in monitoring such events in experimental patients. 相似文献
96.
Ohta H Khan MA Nagai I Umemoto N Hamasaki T Ozoe Y 《Archives of insect biochemistry and physiology》2005,59(3):150-160
Tyramine (TA), a biogenic amine, attenuates intracellular cAMP production by acting on its receptor in insects. Several non-biogenic amines were examined for their actions on native and heterologously expressed silkworm TA receptors. 5-(4-Hydroxyphenyl)oxazole, which showed an attenuating effect on cAMP production in silkworm-head membranes, did not attenuate forskolin-stimulated cAMP production in HEK-293 cells expressing the silkworm TA receptor, although the compound bound to the cloned receptor. 2-Phenylethylamines (2-PEAs), which showed positive and negative effects on cAMP production in silkworm-head membranes, inhibited [3H]TA binding to the cloned TA receptor. 2-Chloro-2-(4-chlorophenyl)ethylamine was the most potent inhibitor of [3H]TA binding among the 2-PEAs tested, with an IC50 of 30.4 nM. This compound acted as an antagonist and abolished TA-attenuation of forskolin-stimulated cAMP production in the cloned TA receptor. The discrepancy in the effects of the non-biogenic amines on the native and cloned TA receptors remains to be further examined. A newly synthesized 2-PEA, 2-chloro-2-(4-hydroxyphenyl)ethylamine, attenuated forskolin-stimulated cAMP production in the cloned TA receptor, indicating that the para-hydroxy group is important for the agonist action. 相似文献
97.
Peng HM Morishima Y Jenkins GJ Dunbar AY Lau M Patterson C Pratt WB Osawa Y 《The Journal of biological chemistry》2004,279(51):52970-52977
It is established that neuronal nitric-oxide synthase (nNOS) is ubiquitylated and proteasomally degraded. The proteasomal degradation of nNOS is enhanced by suicide inactivation of nNOS or by the inhibition of hsp90, which is a chaperone found in a native complex with nNOS. In the current study, we have examined whether CHIP, a chaperone-dependent E3 ubiquitin-protein isopeptide ligase that is known to ubiquitylate other hsp90-chaperoned proteins, could act as an ubiquitin ligase for nNOS. We found with the use of HEK293T or COS-7 cells and transient transfection methods that CHIP overexpression causes a decrease in immunodetectable levels of nNOS. The extent of the loss of nNOS is dependent on the amount of CHIP cDNA used for transfection. Lactacystin (10 microM), a selective proteasome inhibitor, attenuates the loss of nNOS in part by causing the nNOS to be found in a detergent-insoluble form. Immunoprecipitation of the nNOS and subsequent Western blotting with an anti-ubiquitin IgG shows an increase in nNOS-ubiquitin conjugates because of CHIP. Moreover, incubation of nNOS with a purified system containing an E1 ubiquitin-activating enzyme, an E2 ubiquitin carrier protein conjugating enzyme (UbcH5a), CHIP, glutathione S-transferase-tagged ubiquitin, and an ATP-generating system leads to the ubiquitylation of nNOS. The addition of purified hsp70 and hsp40 to this in vitro system greatly enhances the amount of nNOS-ubiquitin conjugates, suggesting that CHIP is an E3 ligase for nNOS whose action is facilitated by (and possibly requires) its interaction with nNOS-bound hsp70. 相似文献
98.
99.
Anwar A Knaggs J Service KM McLaren GW Riordan P Newman C Delahay RJ Cheesman C Macdonald DW 《Journal of wildlife diseases》2006,42(1):179-181
Antibodies to Toxoplasma gondii were detected in samples collected from 90 live-trapped adult Eurasian badgers (Meles meles) sampled at three sites (two agricultural and one woodland) in southern England. Serum was tested using a qualitative latex agglutination test procedure and 63 of 90 (70%) badgers tested positive for T. gondii antibodies. Antibody prevalence varied between the sites; 67% and 77% of badgers from agricultural sites and 39% from a nonagricultural site tested positive. 相似文献
100.