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11.
Bortezomib is a chemotherapeutic agent used to treat several cancers; however, it exhibits severe side effects in testicular tissue. We investigated the use of agomelatine to prevent testicular tissue damage caused by bortezomib. We used 36 male Sprague-Dawley rats divided randomly into six equal groups: group 1, no treatment control; group 2, agomelatine treatment only; group 3, bortezomib treatment only for 48 h; group 4, bortezomib + agomelatine treatment for 48 h; group 5, bortezomib treatment only for 72 h; and group 6, bortezomib + agomelatine treatment for 72 h. After treatments, the rats were sacrificed and testicular tissue was harvested. Lipid oxidation (LPO) and superoxide dismutase (SOD) levels in the tissues were determined using biochemical methods. Tissue samples also were examined using histopathological and immunohistochemical techniques. The LPO level was increased, while the SOD level was decreased in the bortezomib treated groups. We found that agomelatine treatment normalized LPO and SOD activities in the bortezomib treated groups. In the spermatogonia and Sertoli cells, the staining density of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) and caspase 3 were decreased in the bortezomib + agomelatine groups at both 48 and 72 h compared to bortezomib only treated groups. We observed maturation arrest, basal membrane thickening, increase in inflammatory cells and connective tissue, and edema between germ cells in the bortezomib only treated groups. By contrast, normal basal membrane, less edema and more normal maturation were observed in the bortezomib + agomelatine groups at 48 and 72 h. We found that agomelatine reduced the damaging effects of bortezomib. The use of agomelatine to prevent bortezomib induced testicular tissue damage in human patients should be investigated further.  相似文献   
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Reverse genetic screens have driven gene annotation and target discovery in model organisms. However, many disease‐relevant genotypes and phenotypes cannot be studied in lower organisms. It is therefore essential to overcome technical hurdles associated with large‐scale reverse genetics in human cells. Here, we establish a reverse genetic approach based on highly robust and sensitive multiplexed RNA sequencing of mutant human cells. We conduct 10 parallel screens using a collection of engineered haploid isogenic cell lines with knockouts covering tyrosine kinases and identify known and unexpected effects on signaling pathways. Our study provides proof of concept for a scalable approach to link genotype to phenotype in human cells, which has broad applications. In particular, it clears the way for systematic phenotyping of still poorly characterized human genes and for systematic study of uncharacterized genomic features associated with human disease.  相似文献   
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We report 26 individuals from ten unrelated families who exhibit variable expression and/or incomplete penetrance of epilepsy, learning difficulties, intellectual disabilities, and/or neurobehavioral abnormalities as a result of a heterozygous microdeletion distally adjacent to the Williams-Beuren syndrome region on chromosome 7q11.23. In six families with a common recurrent ∼1.2 Mb deletion that includes the Huntingtin-interacting protein 1 (HIP1) and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein gamma (YWHAG) genes and that is flanked by large complex low-copy repeats, we identified sites for nonallelic homologous recombination in two patients. There were no cases of this ∼1.2 Mb distal 7q11.23 deletion copy number variant identified in over 20,000 control samples surveyed. Three individuals with smaller, nonrecurrent deletions (∼180–500 kb) that include HIP1 but not YWHAG suggest that deletion of HIP1 is sufficient to cause neurological disease. Mice with targeted mutation in the Hip1 gene (Hip1−/−) develop a neurological phenotype characterized by failure to thrive, tremor, and gait ataxia. Overall, our data characterize a neurodevelopmental and epilepsy syndrome that is likely caused by recurrent and nonrecurrent deletions, including HIP1. These data do not exclude the possibility that YWHAG loss of function is also sufficient to cause neurological phenotypes. Based on the current knowledge of Hip1 protein function and its proposed role in AMPA and NMDA ionotropic glutamate receptor trafficking, we believe that HIP1 haploinsufficiency in humans will be amenable to rational drug design for improved seizure control and cognitive and behavioral function.  相似文献   
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The Ras small GTPase functions as a signaling node and is activated by extracellular stimuli. Upon activation, Ras interacts with a spectrum of functionally diverse downstream effectors and stimulates multiple cytoplasmic signaling cascades that regulate cellular proliferation, differentiation, and apoptosis. In addition to the association of Ras with the plasma membrane, recent studies have established an association of Ras with Golgi membranes. Whereas the effectors of signal transduction by activated, plasma membrane-localized Ras are well characterized, very little is known about the effectors used by Golgi-localized Ras. In this study, we report the identification of a novel Ras-interacting protein, Rain, that may serve as an effector for endomembrane-associated Ras. Rain does not share significant sequence similarity with any known mammalian proteins, but contains a Ras-associating domain that is found in RalGDS, AF-6, and other characterized Ras effectors. Rain interacts with Ras in a GTP-dependent manner in vitro and in vivo, requires an intact Ras core effector-binding domain for this interaction, and thus fits the definition of a Ras effector. Unlike other Ras effectors, however, Rain is localized to perinuclear, juxta-Golgi vesicles in intact cells and is recruited to the Golgi by activated Ras. Finally, we found that Rain cooperates with activated Raf and causes synergistic transformation of NIH3T3 cells. Taken together, these observations support a role for Rain as a novel protein that can serve as an effector of endomembrane-localized Ras.  相似文献   
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Most estrous cycles in cows consist of 2 or 3 waves of follicular activity. Waves of ovarian follicular development comprise the growth of dominant follicles some of which become ovulatory and the others are anovulatory. Ovarian follicular activity in cows during estrous cycle was studied with a special reference to follicular waves and the circulating concentrations of estradiol and progesterone. Transrectal ultrasound examination was carried out during 14 interovulatory intervals in 7 cows. Ovarian follicular activity was recorded together with assessment of serum estradiol and progesterone concentrations. Three-wave versus two-wave interovulatory intervals was observed in 71.4% of cows. The 3-wave interovulatory intervals differed from 2-wave intervals in: 1) earlier emergence of the dominant follicles, 2) longer in length, and 3) shorter interval from emergence to ovulation. There was a progressive increase in follicular size and estradiol production during growth phase of each wave. A drop in estradiol concentration was observed during the static phase of dominant anovulatory follicles. The size of the ovulatory follicle was always greater and produced higher estradiol compared with the anovulatory follicle. In conclusion, there was a predominance of 3-wave follicular activity that was associated with an increase in length of interovulatory intervals. A dominant anovulatory follicle during its static phase may initiate the emergence of a subsequent wave. Follicular size and estradiol concentration may have an important role in controlling follicular development and in determining whether an estrous cycle will have 2 or 3-waves.  相似文献   
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The O-antigen chain from the lipopolysaccharide of Helicobacter pylori strain UA861 was determined to be composed of an elongated type 2 N - acetyllactosamine backbone, -[-->3)-beta-D-Gal-(1-->4)-beta-D-GlcNAc-(1- ]n-->, with approximately half of the GlcNAc units carrying a terminal alpha-d-Glc residue at the O -6 position. The O-chain of H.pylori UA861 was terminated by a N -acetyllactosamine [beta-D-Gal-(1-->4)-beta-D- GlcNAc] (LacNAc) epitope and did not express terminal Lewis X or Lewis Y blood-group determinants as previously found in other H.pylori strains. The absence of terminal Lewis X and Lewis Y blood-group epitopes and the replacement of Fuc by Glc as a side chain in the O- chain of H.pylori UA861 represents yet another type of lipopolysaccharide structure from H.pylori species. These structural differences in H.pylori lipopolysaccharide molecules carry implications with regard to possible different pathogenic events between strains and respective hosts.   相似文献   
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The first Australian record of the lily thrips, Liothrips vaneeckei Priesner, is reported from a bulb farm in Warragul South, Victoria. It is an occasional pest of Lilium bulbs, both in the field and in storage, particularly in the USA and several European countries, and is also infrequently found in considerable numbers on the corms of orchids.  相似文献   
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