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Menani JV Barbosa SP De Luca LA De Gobbi JI Johnson AK 《American journal of physiology. Regulatory, integrative and comparative physiology》2002,282(3):R837-R841
Central cholinergic mechanisms are suggested to participate in osmoreceptor-induced water intake. Therefore, central injections of the cholinergic agonist carbachol usually produce water intake (i.e., thirst) and are ineffective in inducing the intake of hypertonic saline solutions (i.e., the operational definition of sodium appetite). Recent studies have indicated that bilateral injections of the serotonin receptor antagonist methysergide into the lateral parabrachial nucleus (LPBN) markedly increases salt intake in models involving the activation of the renin-angiotensin system or mineralocorticoid hormones. The present studies investigated whether sodium appetite could be induced by central cholinergic activation with carbachol (an experimental condition where only water is typically ingested) after the blockade of LPBN serotonergic mechanisms with methysergide treatment in rats. When administered intracerebroventricularly in combination with injections of vehicle into both LPBN, carbachol (4 nmol) caused water drinking but insignificant intake of hypertonic saline. In contrast, after bilateral LPBN injections of methysergide (4 microg), intracerebroventricular carbachol induced the intake of 0.3 M NaCl. Water intake stimulated by intracerebroventricular carbachol was not changed by LPBN methysergide injections. The results indicate that central cholinergic activation can induce marked intake of hypertonic NaCl if the inhibitory serotonergic mechanisms of the LPBN are attenuated. 相似文献
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Measurement of some Benzylisoquinoline Alkaloids in Different Organs of Persian Poppy during Ontogenetical Stages 下载免费PDF全文
Mahdi Rezaei Mohammad Reza Naghavi Abdol Hadi Hosseinzadeh Alireza Abbasi 《化学与生物多样性》2016,13(5):539-543
Papaver bracteatum, a perennial species, has been known as a rich source of thebaine and a potential alternative to Papaver somniferum for the production of codeine and some semisynthetic antagonist drugs. In this study, ion mobility spectrum (IMS) of the root, leaf, bottom part of stem, upper part of stem, capsule wall, petal, and capsule content during developmental stages of P. bracteatum including annual rosette, perennial rosette, bud initiation, pendulous bud, preflowering, and lancing were investigated. The IMS revealed thebaine, papaverine, and noscapine as the major components of the extracted alkaloids. Based on the results of the study it appears that, at least in part, there is a competition among the biosynthesis pathways of papaverine, noscapine, and morphinan alkaloids from a common source . Root and capsule wall were the most potent organs for extraction of thebaine, while lancing stage was the best developmental stage for thebaine exploitation. However, it seems that total biomass of root and capsule wall plays a key role in the final selection of favorite organ. Although papaverine and noscapine in the stem at preflowering stage had the most quantity, significant amounts were found in the capsule wall. In general, total alkaloid content of leaf was lower than the other plant parts. 相似文献
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Genetic variation and evolutionary origins of parthenogenetic Artemia (Crustacea: Anostraca) with different ploidies 下载免费PDF全文
Using two nuclear (ITS1 and Na+/K+ ATPase) and three mitochondrial (COI, 16S and 12S) markers, we determined the genetic variation and evolutionary relationship of parthenogenetic and bisexual Artemia. Our analyses revealed that mitochondrial genes had higher genetic variation than nuclear genes and that the 16S showed more variety than the other mitochondrial genes in parthenogenetic populations. Triploid parthenogens showed lower genetic variation than diploid ones, whereas the tetra‐ and pentaploids had greater genetic distance than diploid parthenogens. No shared haplotype was found between individuals of parthenogenetic populations and Asian bisexual species with the exception of Na+/K+ ATPase (Artemia tibetiana). Only mitochondrial markers can demonstrate phylogenetic relationships, and showed that the parthenogenetic Artemia is a polyphyletic group in which the diploid lineages share a common ancestor with Artemia urmiana while tetraploids are closely related to Artemia sinica. The triploid and pentaploid linages are likely to be directly derived from diploid and tetraploid parthenogens, respectively. Subsequently, west Asia is origin for di‐/triploids, and tetra‐/pentaploids rose from East Asia. 相似文献
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Razzaghi-Abyaneh M Shams-Ghahfarokhi M Eslamifar A Schmidt OJ Gharebaghi R Karimian M Naseri A Sheikhi M 《Mycopathologia》2006,161(4):245-249
The effects of Akacid plus, a novel guanidine-based polymer first introduced as a biocidal and disinfectant agent were studied on Aspergillus parasiticus growth and its aflatoxin (AF) productivity. The fungus was cultured on yeast extract-sucrose (YES) broth in presence of various twofold serial dilutions of 25% Akacid plus (1.5-96 microL/50 mL medium) and then incubated in shaking condition with 150 rev./min at 28 degrees C for 96 h. Based on obtained results, Akacid plus was found to significantly inhibit both growth and aflatoxin B1 (AFB1) synthesis in very low concentrations in a dose-dependent manner. Fungal growth inhibition was determined in the range of 9.6-99.6% in mycelia exposed to the total concentration range of 1.5-48 microL. A final concentration of 96 microL was necessary to completely inhibit the growth of fungus. Under similar conditions, AFB1 synthesis was found to be strongly inhibited by 8.1-98.0% in presence of 1.5-24 microL Akacid plus with a maximum of 100% by 48 microL concentration. With respect to the unique physico-chemical properties of Akacid plus, its marked inhibitory effects on A. parasiticus growth and its AFB1 synthesis shown for the first time in this study make it a promising candidate for application in prevention programmes of AF contamination of susceptible crops. 相似文献
17.
Danièle Giblot-Ducray Alireza Marefat Michael R. Gillings Neil M. Parkinson John P. Bowman Kathy Ophel-Keller Cathy Taylor Evelina Facelli Eileen S. Scott 《Systematic and applied microbiology》2009
Strains of Xanthomonas translucens have caused dieback in the Australian pistachio industry for the last 15 years. Such pathogenicity to a dicotyledonous woody host contrasts with that of other pathovars of X. translucens, which are characterized by their pathogenicity to monocotyledonous plant families. Further investigations, using DNA-DNA hybridization, gyrB gene sequencing and integron screening, were conducted to confirm the taxonomic status of the X. translucens pathogenic to pistachio. DNA-DNA hybridization provided a clear classification, at the species level, of the pistachio pathogen as a X. translucens. In the gyrB-based phylogeny, strains of the pistachio pathogen clustered among the X. translucens pathovars as two distinct lineages. Integron screening revealed that the cassette arrays of strains of the pistachio pathogen were different from those of other Xanthomonas species, and again distinguished two groups. Together with previously reported pathogenicity data, these results confirm that the pistachio pathogen is a new pathovar of X. translucens and allow hypotheses about its origin. The proposed name is Xanthomonas translucens pv. pistaciae pv. nov. 相似文献
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Daneshafrooz Afsoon Yuzbashian Emad Zarkesh Maryam Asghari Golaleh Mirmiran Parvin Hedayati Mehdi Abooshahab Raziyeh Fanaei S. Melika Khalaj Alireza 《Molecular biology reports》2022,49(1):163-169
Molecular Biology Reports - Adipose tissue (AT) is a passive reservoir for energy storage and an active endocrine organ responsible for synthesizing bioactive molecules called... 相似文献
20.
Vatandoost J Zomorodipour A Sadeghizadeh M Aliyari R Bos MH Ataei F 《Biotechnology progress》2012,28(1):45-51
The Drosophila γ-glutamyl carboxylase (dγC) has substrate recognition properties similar to that of the vertebrate γ-carboxylase (γC), and its carboxylated product yield, in vitro, was shown to be more than that obtained with the human enzyme. However, whether the Drosophila enzyme is able to γ-carboxylate the human vitamin K-dependent (VKD) proteins, such as the human coagulation factor IX (hFIX), as synthesized in cultured Drosophila cells was not known. To examine this possibility, the Drosophila Schnider (S2) cell line was transfected with a metallothionein promoter-regulated hFIX-expressing plasmid. After induction with copper ion, expression efficiency of the active hFIX was analyzed by performing enzyme-linked immunosorbent assey (ELISA) and coagulation test on the culture supernatant of the transfected S2 cells during 72 h of postinduction. In comparison with Chinese hamster ovary cell line, S2 cells showed higher (≈ 12-fold) expression level of the hFIX. The γ-carboxylation of the Drosophila-derived hFIX was confirmed by evaluation of the expressed protein, after being precipitated with barium citrate. The biological activity of the S2 cell-derived hFIX indicated the capability of S2 cells to fulfill the required γ-carboxylation of the expressed hFIX. Coexpression of the human γ-glutamyl carboxylases (hγC) was also shown to improve both expression and γ-carboxylation of the hFIX. This is the first in vivo data to describe the ability of the dγC to recognize the human-based propeptide as substrate, which is an essential step for production of biologically active γ-carboxylated VKD proteins. 相似文献