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The Iranian species in the Chrysis pulchella and C. varidens species groups are investigated. Six species are recognized, two of which are described for the first time: Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. and Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov.. Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. belongs to the C. pulchella group and is recognizable within this species group by its unique blue body coloration, scattered mesosoma punctures, polished pit row with elongated pits, and a small median tooth on the lateral edge of metasomal tergum 3. Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov. belongs to the C. varidens group and is recognizable by the usually colorless apical rim of metasomal tergum 3, and the unique shape of the anterior corners of the scutellum which are enlarged, thickened and directed backward covering the axillary trough. Dichotomous keys and distributional data for Iranian species included in these species groups are provided. Chrysis schwarzi Linsenmaier, 1968 is raised to species rank. The number of Iranian Chrysis species and subspecies is raised to 122.www.zoobank.org/urn:lsid:zoobank.org:pub:F419F860-3B90-4679-9A19-2CF5C255AE6B  相似文献   
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Mice deficient in brain-derived neurotrophic factor (BDNF) develop mature-onset obesity, primarily due to overeating. To gain insight into the mechanism of this hyperphagia, we characterized food intake, body weight, meal pattern, and meal microstructure in young and mature mice fed balanced or high-fat diets. Hyperphagia and obesity occurred in mature but not young BDNF mutants fed a balanced diet. This hyperphagia was mediated by increased meal number, which was associated with normal meal size, meal duration, and satiety ratio. In contrast, the high-fat diet induced premature development of hyperphagia and obesity in young BDNF mutants and a similar magnitude hyperphagia in mature mutants. This hyperphagia was supported by increased meal size and was accompanied by a reduced satiety ratio. Thus the mechanism underlying hyperphagia was present before significant weight gain, but whether it occurred, and whether meal frequency or meal size was altered to support it, was modulated by a process associated with aging and by diet properties. Meal pattern changes associated with the balanced diet suggested meal initiation, and the oropharyngeal positive feedback that drives feeding, were enhanced and might have contributed to overeating in BDNF mutants, whereas negative feedback was normal. Consistent with this hypothesis, meal microstructure revealed that all hyperphagic mutant groups exhibited increased intake rates at meal onset. Therefore, the central nervous system targets of BDNF actions may include orosensory brain stem neurons that process and transmit positive feedback or forebrain neurons that modulate its strength.  相似文献   
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"Candidatus Phytoplasma aurantifolia" is the causative agent of witches' broom disease in the Mexican lime tree (Citrus aurantifolia L.), and is responsible for major tree losses in Southern Iran and Oman. The pathogen is strictly biotrophic, and, therefore, completely dependent on living host cells for its survival. The molecular basis of compatibility and disease development in this system is poorly understood. We applied a proteomics approach to analyse gene expression in Mexican limes infected with "Ca. Phytoplasma aurantifolia". Leaf samples were collected from healthy and infected plants and were analysed using 2-DE coupled with MS. Among 800 leaf proteins that were detected reproducibly in eight biological replicates of healthy and eight biological replicates of infected plants, 55 showed a significant response to the disease. MS resulted in identification of 39 regulated proteins, which included proteins that were involved in oxidative stress defence, photosynthesis, metabolism, and the stress response. Our results provide the first proteomic view of the molecular basis of the infection process and identify genes that could help inhibit the effects of the pathogen.  相似文献   
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We previously reported that severe iron deficiency negatively affects bone microarchitecture. Here we determined whether marginal iron restriction that reflects some human consumption patterns could have similar consequences. Thirty-two weanling female rats were randomly divided into four groups and fed the following diets for 10 weeks: (i) iron-adequate, calcium-adequate (FeA:CaA), (ii) calcium-restricted (FeA:CaR), (iii) iron-restricted (FeR:CaA), and (iv) both calcium- and iron-restricted (FeR:CaR) diets. DEXA analysis revealed that CaR decreased bone mineral density (BMD), and FeR decreased whole-body bone mineral content (BMC). Iron-restricted and calcium-restricted groups had lower BMD than did their adequate counterparts. All treatment-restricted groups had lower BMD in the fourth lumbar (L-4) vertebrae than the FeA:CaA group. Vertebrae BMD was lower in all treatment groups compared to the control group, and for BMC, the CaR groups were lower than the CaA groups and the FeR groups were lower that the FeA groups, and BMC were lower in iron- and calcium-restricted groups. The microarchitecture of the L-4 vertebrae was compromised in FeA:CaR, FeR:CaA, and FeR:CaR: (i) the connectivity density was reduced by FeR and by CaR; and (ii) trabecular number was decreased and trabecular separation was increased by FeR. Cortical thickness of the femur was reduced by both FeR and CaR. Finite element analysis revealed that L-4 vertebrae from the FeR:CaA group had greater internal stress with an applied force than the FeA:CaA group and, thus, would be more likely to break. Chelation of iron in cultured osteoblast cells impaired mineralization but had no impact upon Type I collagen deposition. Iron depletion, similar to that occurring among some human populations, reduced bone strength and microarchitecture based on the in vivo and in vitro results reported here. Impaired mineralization with iron depletion appears to be a possible mechanism for the observed bone abnormalities.  相似文献   
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The genetic diversity among 10 Iranian bread wheat (Triticum aestivum) genotypes was analysed using 12 quality traits, 320 amplified fragment length polymorphisms (AFLP) polymorphic fragments, 491 simple sequence repeats (SSR) alleles and 294 proteome markers. The results revealed that the genotypes differed for quality traits, AFLP, SSR and proteome markers. The average genetic diversity based on quality traits (0.684 with a range of 0.266–0.997) was higher than AFLP (0.502 with a range of 0.328–0.717), SSR (0.503 with a range of 0.409–0.595) and proteome (0.464 with a range of 0.264–0.870) markers. Although there were apparent similarities between the groupings of particular genotypes, the overall correspondence between the distance matrices appeared to be rather low. In this study, the cluster analysis based on AFLP data showed the closest agreement with genotypes’ regions of origin or pedigree information. In addition to the genetic diversity assessment, specific proteins with known function were detected uniquely for the studied genotypes. Our results suggest that the classification based on quality traits and genotypic markers of these wheat genotypes will be useful for wheat breeders to plan crosses for positive traits.  相似文献   
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The rat provides valuable and sometimes unique models of human complex diseases. To fully exploit the rat models in biomedical research, it is important to have access to detailed knowledge of the rat genome organization as well as its relation to the human genome. Rat Chromosome 10 (RNO10) harbors several important cancer-related genes. Deletions in the proximal part of RNO10 were repeatedly found in a rat model for endometrial cancer. To identify functional and positional candidate genes in the affected region, we used radiation hybrid (RH) mapping and single- and dual-color fluorescence in situ hybridization (FISH) techniques to construct a detailed chromosomal map of the proximal part of RNO10. The regional localization of 14 genes, most of them cancer-related (Grin2a, Gspt1, Crebbp, Gfer, Tsc2, Tpsb1, Il9r, Il4, Irf1, Csf2, Sparc, Tp53, Thra1, Gh1), and of five microsatellite markers (D10Mit10, D10Rat42, D10Rat50, D10Rat72, and D10Rat165) was determined on RNO10. For a fifteenth gene, Ppm1b, which had previously been assigned to RNO10, the map position was corrected to RNO6q12-q13.  相似文献   
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We examined nitric oxide mediated regulation of pulmonary arterial and venous smooth muscle (PASM and PVSM, respectively): whether this inhibition is mediated via prejunctional receptors on adrenergic nerve endings; whether NO is neuronally derived; the relationship between degree of inhibition and vessel size; and identification of the signalling mechanisms involved. Canine pulmonary vascular tissues were generally quiescent, while human PASM exhibited spontaneous phasic activity. The nitric oxide (NO) synthesis inhibitor Nomega-nitro-L-arginine (L-NNA; 10(-4) M) increased tone and enhanced phasic activity. Electrical field stimulation (EFS) evoked contractions were markedly enhanced by L-NNA in an endothelium-dependent fashion, and antagonized by the NO donor S-nitroso-N-acetylpenicillamine (SNAP; 10(-7) to 10(-5) M). 8-Bromo-cGMP mimicked the effects of SNAP on basal tone and EFS contractions, while an inhibitor of soluble guanylate cyclase mimicked those of L-NNA. While mechanical responses to exogenously added norepinephrine (10(-9)-10(-4) M) were also enhanced by L-NNA and suppressed by SNAP, EFS-evoked excitatory junction potentials were unaffected by SNAP. We conclude that, in human and canine PASM and PVSM, there is a tonic generation of NO originating within the endothelium that does not mediate a prejunctional effect, but which acts postjunctionally to activate a cGMP-dependent pathway within the smooth muscle.  相似文献   
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