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121.
The present study was aimed to investigate the effect of nerolidol on the development of kindling and associate oxidative stress and behavioral comorbidities. Kindling was induced by repeated injections of a sub-convulsive dose of pentylenetetrazol (PTZ-35 mg/kg; i.p.), at an interval of 48?±?2 h for 43 days (21 injections). Nerolidol was administered daily in three doses (12.5, 25 and 50 mg/kg) along with alternate day PTZ injection. To access behavioral comorbidities, animals were subjected to tail suspension test (TST) and passive shock avoidance (PSA) test to evaluate the associated depression and memory impairment respectively on the last day of PTZ administration. Following behavioral assessment, neurotransmitter level and oxidative stress markers were evaluated in brain. The results showed that nerolidol significantly suppressed the progression of kindling. Also, nerolidol ameliorates the kindling associated depression and memory impairment as indicated by decreased immobility time and increased step down latency, respectively, as compared to vehicle control animals. Further, these behavioral observations were complimented with corresponding neurochemical and oxidative stress markers changes. In conclusion, the results of present study showed that nerolidol treatment has protective effect against PTZ-induced kindling and associated oxidative stress and behavioral comorbidities. 相似文献
122.
A. A. Lagunin D. S. Druzhilovsky A. V. Rudik D. A. Filimonov D. Gawande K. Suresh R. Goel V. V. Poroikov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2016,10(1):43-54
Applicability of our computer programs PASS and PharmaExpert for prediction of biological activity spectra of rather complex and structurally diverse phytocomponents of medicinal plants, both separately and in combinations has been evaluated. For this purpose we have created the web-resource containing known information about structural formulas and biological activity of 1906 phytocomponents of 50 Ayurvedic medicinal plants used in Traditional Indian Medicine (TIM) (http://ayurveda.pharmaexpert.ru). The PASS training set was updated by addition of information about structure and biological activity of 946 natural compounds; then the training procedure and validation were performed, to estimate the quality of PASS prediction. It was shown that the differences between the average accuracy of prediction obtained in leave-5%-out cross-validation (94.467%) and in leave-one-out cross-validation (94.605%) are very small thus demonstrating high predictive ability of the program. Results of biological activity spectra prediction for all phytocomponents included in our database coincided in 83.5% of cases with known experimental data. Additional types of biological activity predicted with high probability indicate further promising directions for further studies of certain phytocomponents of some medicinal plants. The analysis of prediction results of sets of phytocomponents in each of 50 medicinal plants was made by the PharmaExpert software. Based on this analysis, we found that the combination of phytocomponents from Passiflora incarnata may exhibit nootropic, anticonvulsant, and antidepressant effects. Experiments carried out in mice models confirmed the predicted effects of P. incarnata extracts. 相似文献
123.
Comparison of the bronchoconstrictor and cardiovascular effects of some tachykinins in guinea pigs 总被引:2,自引:0,他引:2
The effects of three tachykinins [substance P (SP), physalaemin (PH), and eledoisin-related peptide (ERP)] were investigated in anesthetized paralyzed guinea pigs. We measured airway resistance (R) and dynamic thoracic elastance (E) with a computerized technique, and blood pressure via a carotid artery. Tachykinins injected iv or intra-aortically (ia) induced dose-dependent increases in R and E, 4 times greater on iv than ia injection. They did not give rise to tachyphylaxis. As a bronchoconstrictor, PH was 5.0X and ERP 1.8X more potent than SP; time to peak response was longer for PH than for ERP and SP; and hypotensive responses, which were of similar magnitude for all three substances, lasted longest after PH. Bronchoconstrictor responses were unaltered by bilateral vagotomy, atropine, mecamylamine, and mepyramine. Morphine reduced PH-induced increases in R (P less than 0.01) and E (P less than 0.05), which were not reversed by naloxone, and capsaicin treatment 1 week before the experiments reduced both SP- and PH-induced increases in E (P less than 0.05). [D-Pro2,D-Trp7,9]-SP reduced ERP-induced increases in R and E, and [D-Arg1,D-Pro2,D-Trp7,9,Leu11]-SP reduced both SP- and PH-induced increases in R and E. We conclude that PH is the most potent bronchoconstrictor of the tachykinins tested. Tachykinin-induced bronchospasm is 'non-reflex' arising via a direct effect on airway smooth muscle; the release of histamine, acetylcholine, or other tachykinins is not involved in the responses. [D-Pro2,D-Trp7,9]-SP is more effective at SP-E receptors, and [D-Arg1,D-Pro2,D-Trp7,9,Leu11]-SP at SP-P receptors; both types of receptor are located all along the airways. 相似文献
124.
Decomposition of two species of Salvina, S. molesta Mitchell and S. cucullata Roxb. was studied for 220 days by the litter bag method. Salvinia molesta decomposes faster in the initial stages and S. cucullata in the later stages of decomposition. The release of nutrients is rapid during the first seven days and is ascribed to leaching. The rate of release of nutrients differs in the two species, with higher rates for P, Ca and Mg in S. molesta and for N in S. cucullata. 相似文献
125.
A new species, Anaphalis himachalensis (Asteraceae) is described from the Lahaul-Spiti district of Himachal Pradesh in North-West Himalayas. 相似文献
126.
Protoplasts of uniform size were prepared from mononucleated conidiospores of Sporotrichum thermophile. Conidia were preincubated in glucose yeast extract medium at 45 C for 4 h. The conidia were collected resuspended in buffer containing 0.6 M KCl (as stabilizer), and incubated with Novozyme SP249 and Cellulase CP at 37 C for 6 h. The protoplasts were separated from cell wall fragments and intact conidia by centrifugation over 50% sucrose. The purified protoplasts were regenerated in glucose yeast extract broth after 7 h of incubation at 45 C. 相似文献
127.
128.
The relationships between applied pure moments at the occiput (C0) and the resulting rotations at the atlanto-occipital (C0-C1) and atlanto-axial (C1-C2) joints are quantified. In axial twist, with a moment of 0.3 Nm, a mean rotation of about 2.5 degrees and 23.3 degrees was observed at C0-C1 and C1-C2 units respectively. Both the atlas and axis contributed to produce lateral bending motion. The ratio between extension and flexion rotations at C0-C1 was 2.5:1. Lateral bending and axial rotations were strongly coupled to each other. The occipito-atlanto-axial complex exhibited a large 'neutral zone' compared to lower cervical spine segments. The likely clinical significance of these findings are discussed. 相似文献
129.
A collection of strains containing genetically linked alternating antibiotic resistance elements for genetic mapping of Escherichia coli. 总被引:165,自引:1,他引:164
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M Singer T A Baker G Schnitzler S M Deischel M Goel W Dove K J Jaacks A D Grossman J W Erickson C A Gross 《Microbiological reviews》1989,53(1):1-24
We present a collection of 182 isogenic strains containing genetically linked antibiotic resistance elements located at approximately 1-min intervals around the Escherichia coli chromosome. At most positions both Tn10 (Tetr) and TN10kan (Kanr) elements are available, so that the collection contains a linked set of alternating antibiotic resistance markers. The map position of each insertion has been aligned to the E. coli genetic map as well as to the Kohara ordered clone bank. These strains are designed to be used in a rapid two-step mapping system in E. coli. In the first step, the mutation is localized to a 5- to 15-min region of the chromosome by Hfr mapping with a set of Hfr strains containing either Tn10 or Tn10kan elements located 20 min from their respective origins of transfer. In the second step, the mutation is localized to a 1-min region by P1 transduction, with a collection of isogenic insertion strains as donors. We discuss the uses of this collection of strains to map and eventually to clone a variety of mutations in E. coli. 相似文献
130.
Summary A patient with partial trisomy 22 (PT22) is presented. Inheritance is presumed to be due to secondary nondisjunction in her mother, who has a balanced translocation t(11;22)(q25;q13). The problem of the phenotypic heterogeneity observed with this chromosome change is discussed. 相似文献