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1.
Objective: To test the mosquitocidal potential of leaf extracts of Pouteria campechiana prepared with different solvents and elucidate the structure of an isolated mosquitocidal compound. Methods: The leaf extracts of Pouteria campechiana prepared with three solvents(petroleum benzene, ethyl acetate and acetone) and potential bioactive fractions were tested against various stages of Aedes aegypti and Culex quinquefasciatus by using the WHO protocols, and the chemical profile and its functional groups were identified by GC-MS and Fourier transmissioninfrared spectroscopy(FT-IR). The structure of bioactive compound was characterized by nuclear magnetic resonance(NMR) spectral technique. Results: The preliminary phytochemical results revealed the presence of alkaloids, amino acids, flavonoids, quinones, saponins, steroids, tannins, and terpenoids in the acetone extract. A significant toxic potential was observed in the acetone extract against both Aedes aegypti and Culex quinquefasciatus mosquitoes. The acetone extract exhibits remarkable larvicidal(LC_(50): 12.232 μg/mL and LC_(90): 63.970 μg/mL), pupicidal(LC_(50): 18.949 μg/mL and LC_(90): 167.669 μg/m L) and adulticidal(LC_(50): 20.689 μg/mL and LC_(90): 72.881 μg/mL) effects against Aedes aegypti. Furthermore, the same extract was subjected to isolation of bioactive compound by GCMS and FT-IR analysis. GC-MS results showed the presence of 5 major compounds, and octacosane(18.440%) was detected as the predominant compound. The FT-IR result of acetone extract demonstrated the presence of various functional groups like alkanes/alkynes, ester, aromatic and amides. The NMR spectrum results of isolated compound were well matched to glycoside linked flavonoids. Based on the chromatography and spectral techniques the isolate molecule was identified as myricitrin by FT-IR and nuclear magnetic resonance spectral data. Conclusion: The isolated compound myricitrin possesses a significant toxic effect in all stages of Aedes aegypti and Culex quinquefasciatus mosquito's with lowest LC_(50) and LC_(90) values.  相似文献   
2.
In our search for new anticancer drugs, a series of binuclear ruthenium(III) thiosemicarbazone complexes of the type [RuCl2(EPh3)]2L (where E = P/As; L = binucleating monobasic tridentate thiosemicarbazone ligand) have been synthesized. Structural features were determined by various physico-chemical and spectral techniques. The interactions of these complexes with CT-DNA were investigated by absorption spectral study, indicates that the binuclear ruthenium(III) complexes form adducts with DNA and has intrinsic binding constant in the range of 1.0 × 104–7.9 × 104 M?1. The free radical scavenging activity of binuclear ruthenium(III) complexes have been determined by their interaction with the stable DPPH free radical. All the complexes exhibited significant antiproliferative activity against human breast cancer line, MCF-7. This research may provide knowledge that is an excellent backdrop for the rational design of promising drugs.  相似文献   
3.
The recommended operative management of unruptured sinus of Valsalva aneurysm consists of closure of the mouth of the aneurysm with or without aortic valve surgery. We report a case of unruptured aneurysm producing right ventricular outflow tract obstruction. Closure of the mouth of the aneurysm failed to relieve the obstruction, which was subsequently achieved by excising the aneurysmal wall overlying the outflow tract.  相似文献   
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5.
The medical records of 238 patients treated for mandibular fractures at Sri Ramachandra Dental College and Hospital, India, over a period of 4 years were reviewed. Of the total 238 patients with mandibular fractures, 81% were males, and 19% were females. The majority of the patients were 21 to 30 years of age. Road traffic accidents, especially people traveling on motorcycles, accounted for 73% of all patients, with a high prevalence during the month of September and on Saturdays. The most common area of fracture was in the parasymphysis region (35.2%) followed by the condyle region (22.6%).  相似文献   
6.
The pathogenesis of glycerol-induced myoglobinuric acute renal failure involves ischemia, vascular congestion and reactive oxygen metabolites. In this study, we have investigated for the first time, the role of ferulic acid in attenuating glycerol-induced nephrotoxicity. Male Wistar rats were injected intramuscularly with 8?mL/kg body weight of 50% glycerol, glycerol?+?ferulic acid at the dose of 5, 10, 15, 20 and 25?mg/kg body weight. After 24?h, the rats were sacrificed and the kidneys were removed for histological and immunohistochemical studies. Furthermore, determinations of lipid peroxidation (LPO) as well as antioxidant enzymes were also analyzed; blood, urine samples were collected in order to quantify renal function and nitric oxide generation, respectively. Glycerol-induced rats showed a significant increase in the level of urinary markers assessed in serum as well as kidney and these were reversed upon ferulic acid treatment. A significant increase in urine nitric oxide, serum as well as kidney LPO, decrease in activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and reduced glutathione were observed in glycerol-induced rats. Immunohistochemical study in glycerol-induced rats demonstrated an increase in the level of nuclear factor-kappaB (NF-κB). All these effects induced by glycerol were reduced upon treatment with ferulic acid in a dose-dependent manner. To conclude, ferulic acid enhances antioxidants and decreases NF-κB, thereby protecting the cells against stress induced by glycerol.  相似文献   
7.
Dendritic cells (DCs) are potent antigen-presenting cells and are capable of activating naive T cells. Gene transfer of tumor antigen and cytokine genes into DCs could be an important strategy for immunotherapeutic applications. Dendritic cells derived from peripheral blood monocytes do not divide and are therefore poor candidates for gene transfer by Moloney murine leukemia virus (Mo-MuLV)-based retroviral vectors. Lentiviral vectors are emerging as a powerful tool for gene delivery into dividing and nondividing cells. A three-plasmid expression system pseudotyped with the envelope from vesicular stomatitis virus (VSV-G) was used to generate lentiviral vector particles expressing enhanced green fluorescent protein (EGFP). Peripheral blood monocyte-derived DCs were cultured in the presence of GM-CSF and IL-4 and transduced with lentiviral or Mo-MuLV-based vectors expressing EGFP. FACS analysis of lentiviral vector-transduced DCs derived either from normal healthy volunteers or from melanoma patients demonstrated transduction efficiency ranging from 70 to 90% compared with 2-8% using Mo-MuLV-based vectors pseudotyped with VSV-G. Comparison of lentiviral vectors expressing EGFP driven by CMV or human PGK promoters showed similar levels of transgene expression. Lentiviral vector preparations produced in the absence of HIV accessory proteins transduced DCs at efficiencies equal to vectors produced with accessory proteins. Alu-HIV-1 LTR PCR demonstrated the genomic integration of the lentiviral vector in the transduced DCs. Transduced cells showed characteristic dendritic cell phenotype and strong allostimulatory capacity and maintained the ability to respond to activation signals such as CD40 ligand and lipopolysaccharide. These results provide evidence that lentiviral vectors are efficient tools for gene transfer and expression in monocyte-derived DCs that could be useful for immunotherapeutic applications.  相似文献   
8.
The involvement of brain monoamine systems in the discriminative stimulus effects of methamphetamine (MA) was studied in squirrel monkeys by evaluating the effects of differentially selective monoamine uptake inhibitors alone and in combination. In monkeys discriminating i.m. injections of 0.3 mg/kg MA from saline, methamphetamine (0.01-0.3 mg/kg), and dopamine transporter (DAT) inhibitors, including 1-[2-(bis(4-fluorophenyl)-methoxy)ethyl]-4-(3-phenylpropyl)piperazine (GBR 12909; 1.0-17.8 mg/kg) and its analogs AM2502 (1.0-17.8 mg/kg), AM2506 (1.0-30.0 mg/kg), AM2515 (1.0-17.8 mg/kg), and AM2517 (1.0-5.6 mg/kg), produced dose-related increases in responding on the MA-associated lever and, at the highest doses, full substitution. The time course of MA-like effects was similar for equivalent (3.0 mg/kg) doses of GBR 12909 and its most potent analog, AM2517. Unlike the DAT blockers, the selective 5-hydroxytryptamine (serotonin) uptake inhibitor clomipramine (1.0-10.0 mg/kg) and the selective norepinepherine (NE) uptake inhibitor desipramine (1.0-10 mg/kg) produced responding primarily on the saline lever. The selective NE uptake inhibitor nisoxetine partially substituted at the highest dose tested (10.0 mg/kg). Pretreatment with GBR 12909 or AM2517 enhanced the discriminative stimulus effects of MA, shifting the dose-effect curve leftward. The NE uptake inhibitors desipramine or nisoxetine also enhanced the discriminative stimulus effects of MA, whereas clomipramine only attenuated them. These results support the view that dopaminergic mechanisms play a prominent role in the discriminative stimulus effects of MA in monkeys, whereas involvement of serotonergic and noradrenergic systems may be limited to a modulatory role.  相似文献   
9.
High incidence rates have been reported for parastomal hernias after colostomies, particularly end colostomies. In addition to cosmetic disfigurement, parastomal hernias also cause several functional problems in stoma management, and their repair becomes essential. While a variety of open techniques have been described for their management, including the extreme step of stoma relocation, laparoscopic techniques offer a viable and possibly better option. We present a case of parastomal hernia and describe our technique of repair.  相似文献   
10.
Progress toward clinical application of ESC-derived hematopoietic cellular transplantation will require rigorous evaluation in a large animal allogeneic model. However, in contrast to human ESCs (hESCs), efforts to induce conclusive hematopoietic differentiation from rhesus macaque ESCs (rESCs) have been unsuccessful. Characterizing these poorly understood functional differences will facilitate progress in this area and likely clarify the critical steps involved in the hematopoietic differentiation of ESCs. To accomplish this goal, we compared the hematopoietic differentiation of hESCs with that of rESCs in both EB culture and stroma coculture. Initially, undifferentiated rESCs and hESCs were adapted to growth on Matrigel without a change in their phenotype or karyotype. Subsequent differentiation of rESCs in OP9 stroma led to the development of CD34(+)CD45(-) cells that gave rise to endothelial cell networks in methylcellulose culture. In the same conditions, hESCs exhibited convincing hematopoietic differentiation. In cytokine-supplemented EB culture, rESCs demonstrated improved hematopoietic differentiation with higher levels of CD34(+) and detectable levels of CD45(+) cells. However, these levels remained dramatically lower than those for hESCs in identical culture conditions. Subsequent plating of cytokine-supplemented rhesus EBs in methylcellulose culture led to the formation of mixed colonies of erythroid, myeloid, and endothelial cells, confirming the existence of bipotential hematoendothelial progenitors in the cytokine-supplemented EB cultures. Evaluation of four different rESC lines confirmed the validity of these disparities. Although rESCs have the potential for hematopoietic differentiation, they exhibit a pause at the hemangioblast stage of hematopoietic development in culture conditions developed for hESCs.  相似文献   
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