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91.
The chemical composition of the essential oil obtained from the aerial flowering parts of Ziziphora clinopodioides subsp. bungeana (Juz.) Rech. f. was analyzed by GC and GC-MS. Thirty-two components representing 97.1% of the total oil were identified. Oxygenated monoterpenes (94.3%) were the predominant fraction of the oil with pulegone (65.2%), isomenthone (11.9%), 1,8-cineole (7.8%) and piperitenone (6.5%) as the main constituents. Antibacterial activity of the oil and also its two main components (pulegone and 1,8-cineole) were tested against seven bacteria. It was found that the oil exhibited interesting antibacterial activity against Staphylococcus epidermidis, S. aureus, Escherichia coli and Bacillus subtilis with MIC values of 3.75 mg/ml.  相似文献   
92.
Liu Y  Abdel Samad O  Zhang L  Duan B  Tong Q  Lopes C  Ji RR  Lowell BB  Ma Q 《Neuron》2010,68(3):543-556
Itch can be suppressed by painful stimuli, but the underlying neural basis is unknown. We generated conditional null mice in which vesicular glutamate transporter type 2 (VGLUT2)-dependent synaptic glutamate release from mainly Nav1.8-expressing nociceptors was abolished. These mice showed deficits in pain behaviors, including mechanical pain, heat pain, capsaicin-evoked pain, inflammatory pain, and neuropathic pain. The pain deficits were accompanied by greatly enhanced itching, as suggested by (1) sensitization of both histamine-dependent and histamine-independent itch pathways and (2) development of spontaneous scratching and skin lesions. Strikingly, intradermal capsaicin injection promotes itch responses in these mutant mice,?as opposed to pain responses in control littermates. Consequently, coinjection of capsaicin was no longer able to mask itch evoked by pruritogenic compounds. Our studies suggest that synaptic glutamate release from a group of peripheral nociceptors is required to sense pain and suppress itch. Elimination of VGLUT2 in these nociceptors creates a mouse model of chronic neurogenic itch.  相似文献   
93.
A phytochemical investigation on the ethyl acetate soluble fraction of Lonicera quinquelocularis (whole plant) led to the first time isolation of one new phthalate; bis(7-acetoxy-2-ethyl-5-methylheptyl) phthalate (3) and two new benzoates; neopentyl-4-ethoxy-3, 5-bis (3-methyl-2-butenyl benzoate (4) and neopentyl-4-hydroxy-3, 5-bis (3-methyl-2-butenyl benzoate (5) along with two known compounds bis (2-ethylhexyl phthalate (1) and dioctyl phthalate (2). Their structures were established on the basis of spectroscopic analysis and by comparison with available data in the literature. All the compounds (1–5) were tested for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities in dose dependent manner. The IC50 (50% inhibitory effect) values of compounds 3 and 5 against AChE were 1.65 and 3.43 µM while the values obtained against BChE were 5.98 and 9.84 µM respectively. Compounds 2 and 4 showed weak inhibition profile.  相似文献   
94.
Paracrine secretion of mediators may be the main route by which stem cells protect against injuries. Stem cells commonly secrete different bioactive molecules. In this study, we examined the hypothesis that administration of conditioned media of stem cells can diminish the burden of kidney injury. A mouse model of cisplatin-induced nephropathy was developed to test the putative renoprotective effects of conditioned media of human umbilical cord blood USSCs (unrestricted somatic stem cells) as well as mouse bone marrow MSCs (mesenchymal stem cells). None of these two types of conditioned medium could protect against kidney failure in terms of serum urea and creatinine, histopathologic examinations and physical activity score. Neither MSC- nor USSC-conditioned media were effective in protecting against kidney injury in our study. Possible explanations for our observations are offered, and related literature is reviewed.  相似文献   
95.
96.
A new strain, SD12, was isolated from tannery waste polluted soil and identified as Pseudomonas aeruginosa on the basis of phenotypic traits and by comparison of 16S rRNA sequences. This bacterium exhibited broad-spectrum antagonistic activity against phytopathogenic fungi. The strain produced phosphatases, cellulases, proteases, pectinases, and HCN and also retained its ability to produce hydroxamate-type siderophore. A bioactive metabolite was isolated from P. aeruginosa SD12 and was characterized as 1-hydroxyphenazine ((1-OH-PHZ) by nuclear magnetic resonance (NMR) spectral analysis. The strain was used as a biocontrol agent against root rot and wilt disease of pyrethrum caused by Rhizoctonia solani. The stain is also reported to increase the growth and biomass of Plantago ovata. The purified compound, 1-hydroxyphenazine, also showed broad-spectrum antagonistic activity towards a range of phytopathogenic fungi, which is the first report of its kind.  相似文献   
97.
Adoptive T cell therapy for cancer patients optimally requires participation of CD4 T cells. In this phase I/II study, we assessed the therapeutic effects of adoptively transferred IL-10- and IFN-γ-producing CD4 effector cells in patients with recurrent ovarian cancer. Using MUC1 peptide and IL-2 for ex vivo CD4 effector cell generation, we show that three monthly treatment cycles of autologous T cell restimulation and local intraperitoneal re-infusion-modulated T cell-mediated immune responses that were associated with enhanced patient survival. One patient remains disease-free, another patient experienced prolonged survival for nearly 16?months with recurrent disease, and two patients expired within 3-5?months following final infusion. Prolonged survivors showed elevated levels of systemic CD3(+)CD4(+)CD25(+) and CD3(+)CD4(+)CD25(-) T cells when compared to that of pre-treatment levels and similarly treated short-term survivors. Such cell populations among these patients contained variable levels of "Inducible" Tr1 (CD4(+)CD25(-)FoxP3(-)IL-10(+)) and "Natural" (CD4(+)CD25(+)CD45RO(+)FoxP3(+)) TReg cell numbers and ratios that were associated with prolonged and/or disease-free survival. Moreover, peptide-restimulated T cells from these patients showed an elevation in both IFN-γ production, memory cell phenotype, and select TNF family ligands associated with enhanced T cell survival and apoptosis-inducing activities. This suggests that intraperitoneally administered Th1-like cells, producing elevated levels of IL-10, may require and/or induce differential levels of distinct systemic TReg subpopulations that influence, in part, long-term tumor immunity and enhanced memory/effector CD4-mediated therapeutic potentials. Furthermore, treatment efficacy and enhanced memory cell phenotype did not appear to be dependent on TReg cell numbers but upon ratios of "Inducible" and "Natural" TReg subpopulations.  相似文献   
98.
Meloidoderita salina sp. n. is described and illustrated from the halophytic plant Atriplex portulacoides L. (sea purslane) growing in a micro-tidal salt marsh in the Mont-Saint-Michel Bay in France. This new species is the first member of Meloidoderita Poghossian, 1966 collected from a saline environment, and is characterized by the following features: sedentary mature females having a small swollen body with a clear posterior protuberance; slightly dorsally curved stylet, 19.9 µm long, with posteriorly sloping knobs; neck region irregular in shape and twisted; well developed secretory-excretory (S–E) pore, with markedly sclerotized S-E duct running posteriorly; prominent uterus bordered by a thick hyaline wall and filled with eggs. The adult female transforms into a cystoid. Eggs are deposited in both egg-mass and cystoid. Cystoids of Meloidoderita salina sp. n. display a unique sub-cuticular hexagonal beaded pattern. Male without stylet, pharyngeal region degenerated, S-E duct prominent, deirids small, developed testis 97.5 µm long, spicules 18.4 µm long, cloacal opening ventrally protruded, small phasmids posterior to cloaca opening and situated at 5.9 (3.2–7.7) µm from tail end, and conical tail ending in a rounded terminus marked with one (rarely two) ventrally positioned mucro. Additionally, some young malesof the new species were observed enveloped in the last J2 cuticle. Second-stage juvenile body 470 µm long, with a 16.4 µm long stylet, prominent rounded knobs set off from the shaft, hemizonid anterior and adjacent to S-E pore, small deirids located just above S-E pore level, genital primordium located at 68–77% of body length, phasmids small and located at about 19 µm from tail tip, and tail 38.7 µm long, tapering to finely pointed terminus with a finger-like projection. Phylogenetic analyses based on the nearly full length small subunit ribosomal DNA sequences of Meloidoderita salina sp. n. revealed a close relationship of the new species with Sphaeronema alni Turkina & Chizhov, 1986 and placed these two species sister to the rest of Criconematina.  相似文献   
99.
Proteinuria is a hallmark of chronic kidney disease (CKD) and cardiovascular disease (CVD), and a good predictor of clinical outcome. Selective endothelin A (ETA) receptor antagonist used with renin-angiotensin system (RAS) inhibitors prevents development of proteinuria in CKD. However, whether the improvement in proteinuria would have beneficial effects on CVD, independent of RAS inhibition, is not well understood. In this study, we investigated whether atrasentan, an ETA receptor antagonist, has renal and cardiovascular effects independent of RAS inhibition. Male Dahl salt sensitive (DSS) rats, at six weeks of age, received water with or without different doses of atrasentan and/or enalapril under high salt (HS) diet or normal diet (ND) for 6 weeks. At the end of 12th week, atrasentan at a moderate dose significantly attenuated proteinuria and serum creatinine without reducing mean arterial pressure (MAP), thereby preventing cardiac hypertrophy and improving cardiac function. ACE inhibitor enalapril at a dose that did not significantly lowered BP, attenuated cardiac hypertrophy while moderately improving cardiac function without reducing proteinuria and serum creatinine level. Nonetheless, combined therapy of atrasentan and enalapril that does not altering BP exerted additional cardioprotective effect. Based on these findings, we conclude that BP independent monotherapy of ETA receptor antagonist attenuates the progression of CKD and significantly mitigates CVD independent of RAS inhibition.  相似文献   
100.
在害虫治理中, 在消费或贮藏粮食加工产品的建筑设施或场所进行害虫防治需要将杀虫剂施用在各种基质表面上。为了测定不同基质表面上杀虫剂的药效, 将四纹豆象Callosobruchus maculatus (F.)成虫接触田间推荐剂量的阿维菌素、 溴氰菊酯和毒死蜱。结果表明: 施用在玻璃、 瓷砖、 塑料和纸盘表面上, 阿维菌素对四纹豆象成虫的致死率分别为63.33%, 22.41%, 12.9%和11.9%, 而溴氰菊酯在这4种基质表面上对四纹豆象成虫的致死率分别为 55%, 44.2%, 41.3%和 37.4%。在所有基质表面上接触毒死蜱, 四纹豆象成虫的死亡率均为100%。对数据进行的Probit 分析表明, 毒死蜱制剂在玻璃、 瓷砖、 塑料和纸盘上对四纹豆象成虫 的LC50 值分别为 8.66, 13.6, 29.16和 56.5 μg/mL, 阿维菌素制剂的相应数值分别为119.4, 446.2, 774.2 和 836.4 μg/mL, 溴氰菊酯制剂的相应数值分别为 1 008, 1 131, 1 210和 1 336 μg/mL。据此推断, 毒死蜱对四纹豆象的毒性最强, 且在玻璃、 瓷砖、 塑料和纸盘表面上的毒性依次降低。  相似文献   
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