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The length–weight relationships (LWRs) for four little‐known shark species collected in the Persian Gulf and Oman Sea from March 2014 to September 2015 are presented, namely: Carcharhinus dussumieri, Carcharhinus macloti, Chiloscyllium arabicum, and Chaenogaleus macrostoma.  相似文献   
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Glutamate receptors in mesolimbic areas such as the nucleus accumbens, ventral tegmental area, prefrontal cortex (PFC), and hippocampus (HIP) are a component of the mechanisms of drug-induced reward and can modulate the firing pattern of dopaminergic neurons in the reward system. In addition, several lines of study have indicated that cAMP response element-binding protein (CREB) and c-fos have important role in morphine-induced conditioned place preference (CPP) induced by drugs of abuse, such as morphine, cocaine, nicotine, and alcohol. Therefore, in the present study, we investigated the changes in phosphorylated CREB (p-CREB) and c-fos induction within the nucleus accumbens (NAc), HIP, and PFC after intracerebroventricular (ICV) administration of different doses of CNQX or vehicle during extinction period or reinstatement of morphine-induced CPP. In all groups, the CPP procedure was done; afterward, the conditioning scores were recorded by Ethovision software. After behavioral test recording, we dissected out the NAc, HIP, and PFC regions and measured the p-CREB/CREB ratio and c-fos level by Western blot analysis. Our results showed that administration of CNQX significantly shortened the extinction of morphine CPP. Besides, ICV microinjection of CNQX following extinction period decreased the reinstatement of morphine CPP in extinguished rats. In molecular section, in treatment group, all mentioned factors were dose-dependently decreased in comparison with vehicle group (DMSO) after ICV microinjection of different doses of CNQX but not in pre-extinction microinjection. These findings suggested that antagonism of AMPA receptor decreased p-CREB/CREB ratio and c-fos level in the PFC, NAc, and HIP. Modulation of the drug memory reconsolidation may be useful for faster extinction of drug-induced reward and attenuation of drug-seeking behavior.  相似文献   
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Many viruses alter different stages of apoptosis of infected cells as a strategy for successful infection. Few studies have addressed mechanisms of equine herpesvirus 1 (EHV-1) strain-induced cell death. We investigated the effect of an abortigenic strain (AR8 strain) on heterologous Madin–Darby bovine kidney cells and homologous equine dermis (ED) cells cell lines. We compared morphologic and biochemical features of early and late apoptosis at different postinfection times. We investigated translocation of phosphatidylserine to the cell surface, nuclear fragmentation and changes in the cytoskeleton using flow cytometry and annexin V/propidium iodide staining, DNA laddering, terminal deoxynucleotidyl transferase UTP nick-end labeling assay and immunofluorescence staining of cytokeratin 18 cleavage. AR8 EVH-1 strain interfered with apoptosis in both cell lines, particularly during the middle stage of the replication cycle; this was more evident in ED cells. Although this antiapoptotic effect has been reported for other alpha herpesviruses, our findings may help elucidate how EHV-1 improves its infectivity during its cycle.  相似文献   
35.
Jailing of a side-branch is a known complication of stent implantation, and makes access to the side-branch difficult, especially if the stent is of the self-expanding type. Although plain balloon angioplasty is feasible for the jailed side-branches, the use of newer devices (a stent, Rotablation or atherectomy) has not been described. We describe a novel way of treating a side-branch jailed by a self-expanding stent by using stent implantation through the strut of a self-expanding stent.  相似文献   
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Background

Experimental studies support an important role for endothelial nitric oxide synthase (eNOS) in the regulation of angiogenesis. In humans, a common polymorphism exists in the eNOS gene that results in the conversion of glutamate to aspartate for codon 298. In vitro and in vivo studies have suggested a decreased NOS activity in patients with the Asp298 variant. We hypothesized that a genetic-mediated decreased eNOS activity may limit collateral development in patients with chronic coronary occlusions.

Methods

We selected 291 consecutive patients who underwent coronary angiography and who had at least one chronic (>15 days) total coronary occlusion. Collateral development was graded angiographically using two different methods: the collateral flow grade and the recipient filling grade. Genomic DNA was extracted from white blood cells and genotyping was performed using previously published techniques.

Results

Collateral development was lower in patients carrying the Asp298 variant than in Glu-Glu homozygotes (collateral flow grade: 2.64 ± 0.08 and 2.89 ± 0.08, respectively, p = 0.04; recipient filling grade: 3.00 ± 0.08 and 3.24 ± 0.07, respectively, p = 0.04). By multivariable analysis, three variables were independently associated with the collateral flow grade: female gender, smoking, and the Asp298 variant (p = 0.03) while the Asp298 variant was the sole variable independently associated with the recipient filling grade (p = 0.03).

Conclusion

Collateral development is lower in patients with the Asp298 variant. This may be explained by the decreased NOS activity in patients with the Asp298 variant. Further studies will have to determine whether increasing eNOS activity in humans is associated with coronary collateral development.  相似文献   
38.
Abstract The biochemical pathway and genetics of autotrophic ammonia oxidation have been studied almost exclusively in Nitrosomonas europaea. Terrestrial autotrophic ammonia-oxidizing bacteria (AAOs), however, comprise two distinct phylogenetic groups in the beta-Proteobacteria, the Nitrosomonas and Nitrosospira groups. Hybridization patterns were used to assess the potential of functional probes in non-PCR-based molecular analysis of natural AAO populations and their activity. The objective of this study was to obtain an overview of functional gene homologies by hybridizing probes derived from N. europaea gene sequences ranging in size from 0.45 to 4.5 kb, and labeled with 32P to Southern blots containing genomic DNA from four Nitrosospira representatives. Probes were specific for genes encoding ammonia monooxygenase (amoA and amoB), hydroxylamine oxidoreductase (hao), and cytochrome c-554 (hcy). These probes produced hybridization signals, at low stringency (30 degreesC), with DNA from each of the four representatives; signals at higher stringency (42 degreesC) were greatly reduced or absent. The hybridization signals at low stringency ranged from 20 to 76% of the total signal obtained with N. europaea DNA. These results indicate that all four functional genes in the ammonia oxidation pathway have diverged between the Nitrosomonas and Nitrosospira groups. The hao probe produced the most consistent hybridization intensities among the Nitrosospira representatives, suggesting that hao sequences would provide the best probes for non-PCR-based molecular analysis of terrestrial AAOs. Since N. europaea can also denitrify, an additional objective was to hybridize genomic DNA from AAOs with probes for Pseudomonas genes involved in denitrification. These probes were specific for genes encoding heme-type dissimilatory nitrite reductase (dNir), Cu-type dNir, and nitrous oxide reductase (nosz). No hybridization signals were observed from probes for the heme-type dNir or nosz, but Nitrosospira sp. NpAV and Nitrosolobus sp. 24-C hybridized, under low-stringency conditions, with the Cu-type dNir probe. These results indicate that AAOs may also differ in their mechanisms and capacities for denitrification.  相似文献   
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Cannabidiol (CBD) is a non-psychotomimetic compound with strong potential to decrease the psychostimulant’s rewarding effect with unclear receptors. Furthermore, as a part of the reward circuit, the hippocampus plays a crucial role in regulating the reward properties of drugs as determined by conditioned place preference (CPP). In the current research, CPP was used to evaluate the role of intra-CA1 microinjection of D1-like dopamine receptor antagonists in CBD's inhibitory effect on the acquisition and expression phases of methamphetamine (METH). Animals were treated by METH (1 mg/kg; sc) in a five-day schedule to induce CPP. To find out the impact of D1-like dopamine receptor antagonist, SCH23390, in the CA1 on the inhibitory influence of CBD on the acquisition of METH, the rats received intra-CA1 administration of SCH23390 (0.25, 1, and 4 µg/0.5 µl) following ICV treatment of CBD (10 µg/5 µl) over conditioning phase of METH. Furthermore, animals were given SCH23390 in the CA1 ensuing ICV microinjection of CBD (50 µg/5 µl) in the expression phase of METH to rule out the influence of SCH23390 on the suppressive effect of CBD on the expression of METH CPP. Intra-CA1 microinjection of SCH23390 abolished CBD's suppressive impact on both METH-induced CPP phases without any side effect on the locomotion. The current research disclosed that CBD inhibited the rewarding characteristic of METH via D1-like dopamine receptors in the CA1 region of the hippocampus.

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