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1.
Summary A cloned cDNA partial copy of a soybean leghemoglobin mRNA was used to probe genomic DNA of four species of actinorhizal plants. Southern blot hybridization revealed the presence of sequences with homology to the leghemoglobin probe in DNA from Alnus glutinosa, Casuarina glauca, Ceanothus americanus and Elaeagnus pungens. The hybridization patterns of the restriction fragments revealed some fragment size conservation between the DNA of soybean and the DNA of four actinorhizal plants which are taxonomically unrelated to soybean or to each other. The results presented here indicate that globin gene sequences are much more widely distributed in the plant kingdom than has previously been thought. Furthermore, if sequence conservation is actually as high as the restriction fragment patterns suggest, the evolution of the DNA surrounding the globin sequences has been highly constrained.  相似文献   
2.
Hepatitis C virus (HCV) subtypes are pre-requisite to predict endemicity, epidemiology, clinical pathogenesis, diagnosis, and treatment of chronic hepatitis C infection. HCV genotypes 4 and 1 are the most prevalent in Saudi Arabia, however; less consensus data exist on circulating HCV subtypes in infected individuals. This study was aimed to demonstrate the virological surveillance, phylogenetic analysis, and evolutionary relationship of HCV genotypes 4 and 1 subtypes in the Saudi population with the rest of the world. Fifty-five clinical specimens from different parts of the country were analyzed based on 5′ untranslated region (5′ UTR) amplification, direct sequencing, and for molecular evolutionary genetic analysis. Pair-wise comparison and multiple sequence alignment were performed to determine the nucleotide conservation, nucleotide variation, and positional mutations within the sequenced isolates. The evolutionary relationship of sequenced HCV isolates with referenced HCV strains from the rest of the world was established by computing pairwise genetic distances and generating phylogenetic trees. Twelve new sequences were submitted to GenBank, NCBI database. The results revealed that HCV subtype 4a is more prevalent preceded by 1a in the Saudi population. Molecular phylogeny predicts the descendants’ relationship of subtype 4a isolates very close to Egyptian prototype HCV strains, while 1a isolates were homogeneous and clustering to the European and North American genetic lineages. The implications of this study highlight the importance of HCV subtyping as an indispensable tool to monitor the distribution of viral strains, to determine the risk factors of infection prevalence, and to investigate clinical differences of treatment outcomes among intergenotypic and intragenotypic isolates in the treated population.  相似文献   
3.

Aim

The development of anticancer drugs with specific targets is of prime importance in modern biology. This study investigates the angiopreventive and in vivo tumor inhibition activities of novel synthetic benzophenone–benzimidazole analogs.

Main methods

The multistep synthesis of novel benzophenone–benzimidazole analogs (8a–n) allowing substitution with methoxy, methyl and halogen groups at different positions on the identical chemical backbone and the variations in the number of substituents were synthesized and characterized. The newly synthesized compounds were further evaluated for cytotoxic and antiproliferative effects against Ehrlich ascites carcinoma (EAC) cells. The potent lead compounds were further assessed for antiangiogenic effects in a CAM model and a tumor-induced vasculature in vivo model. The effect of angioprevention on tumor growth was verified in a mouse model.

Key findings

The cytotoxicity studies revealed that compounds 8f and 8n are strongly cytotoxic. Analyzing the structure–activity relationship, we found that an increase in the number of methyl groups in addition to methoxy substitution at the para position of the benzoyl ring in compound 8n resulted in higher potency compared to 8f. Furthermore, neovessel formation in in vivo systems, such as the chorioallantoic membrane (CAM) and tumor-induced mice peritoneum models, was significantly suppressed and reflected the tumor inhibition observed in mice.

Significance

These results suggest the potential clinical application of compound 8n as an antiangiogenic drug for cancer therapy.  相似文献   
4.
5.
Sajida Khanum 《Phytochemistry》1985,24(7):1625-1626
Studies on the alkaloids from the leaves of Rhazya stricta have afforded a new alkaloid to which the structure 2-methoxy-1,2-dihydrorhazimine has been assigned.  相似文献   
6.
Fries rearrangement of substituted phenyl benzoates 1a-j to substituted hydroxy benzophenones 2a-j was achieved in excellent yield. Further benzoylation of 2a-j to benzoyloxy benzophenones 4a-n, a benzophenone analogue was achieved in good yield. All the newly synthesized compounds were evaluated for their anti-inflammatory activity and were compared with standard drugs. Out of the compounds studied, the compounds 4c, 4e, 4g, 4h and 4k with chloro and methyl substituents at para position showed more potent activity than the standard drugs at all doses tested.  相似文献   
7.
Benzoylation of (hydroxy phenyl) phenyl methanone 2a-g to benzoyl phenyl benzoates 4a-g, a benzophenone analogue, was achieved in good yield. All the newly synthesized compounds were evaluated for their phospholipase A2 [E.C. 3.1.1.4] and hyaluronidase [E.C. 3.2.1.35] enzyme inhibitory activity in snake venom as source and their structure-activity relationship with respect to different groups is reported for the first time. The in vitro PLA2 enzyme inhibitory activity and in vivo anti-inflammatory activity studies of benzoyl phenyl benzoates are illustrated.  相似文献   
8.
This study investigated dream narratives as reflections of the emotional and psychological states of earthquake survivors. Dreams and dreams imagery have reportedly been affected by the emotional and psychological trauma that the dreamer goes through. Dream narratives and dream content ratings used in earlier studies were utilized in this study. Narratives and content ratings were obtained from a sample of 27 volunteer survivors of the October 8, 2005 earthquake in Pakistan (Azad Kashmir area) and 27 volunteer controls from similar demographics. Three independent raters judged the dream narratives and dream content ratings. The judges rating were highly congruent (86.05). Findings revealed that the survivor group had more vivid, unpleasant, horrifying, and hostile dreams compared with the control group. However, there were no significant gender differences. The data suggest that a closer study of dreams can be used to understand the underlying trauma for effective interventions. In addition, interesting emergence of recurrent dreams was seen, which will be independently studied in future. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Cognition-enhancing activity of Bacopa monniera extract (BME) was evaluated against scopolamine-induced amnesic rats by novel object recognition test (NOR), elevated plus maze (EPM) and Morris water maze (MWM) tests. Scopolamine (2 mg/kg body wt, i.p.) was used to induce amnesia in rats. Piracetam (200 mg/kg body wt, i.p.) was used as positive control. BME at three different dosages (i.e., 10, 20 and 40 mg/kg body wt.) improved the impairment induced by scopolamine by increasing the discrimination index of NOR and by decreasing the transfer latency of EPM and escape latency of MWM tests. Our results further elucidate that BME administration has normalized the neurotransmitters (acetylcholine, glutamate, 5-hydroxytryptamine, dopamine, 3,4 dihydroxyphenylacetic acid, norepinephrine) levels that were altered by scopolamine administration in hippocampus of rat brain. BME administration also ameliorated scopolamine effect by down-regulating AChE and up-regulating BDNF, muscarinic M1 receptor and CREB expression in brain hippocampus confirms the potent neuroprotective role and these results are in corroboration with the earlier in vitro studies. BME administration showed significant protection against scopolamine-induced toxicity by restoring the levels of antioxidant and lipid peroxidation. These results indicate that, cognition-enhancing and neuromodulatory propensity of BME is through modulating the expression of AChE, BDNF, MUS-1, CREB and also by altering the levels of neurotransmitters in hippocampus of rat brain.  相似文献   
10.
The development of myeloperoxidase (MPO) inhibitors has been conducted using flufenamic acid as a lead compound. Computational docking of the drug and its analogs in the MPO active site was first attempted. Several molecules were then synthesized and assessed using three procedures for the measurement of their inhibiting activity: (i) the taurine assay, (ii) the accumulation of compound II, and (iii) the LDL oxidation by ELISA. Most of the synthesized molecules had an activity in the same range as flufenamic acid but none of them were able to inhibit the MPO-dependent LDL oxidation. The experiments however gave some useful indications for a rational conception of MPO inhibitors.  相似文献   
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