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91.
The affinity and the density of peripheral-type benzodiazepine binding sites (PBzS) in tissues from the genital organs of female rats were studied during the oestrous cycle. When comparing PBzS density on the day of oestrus to PBzS density on the day of pro-oestrus, a significant increase was observed in the ovary (1.9-fold), oviduct (2.4-fold) and uterus (1.7-fold), but not in the kidney. Serum oestradiol also increased to a maximum on the day of pro-oestrus. The ovarian and uterine PBzS density and serum concentrations of oestradiol and progesterone were measured every 8 h between the days of dioestrus and pro-oestrus. Ovarian and uterine PBzS density increased to a maximal value at 01:00 and 09:00 h, respectively, on the day of pro-oestrus. However, a significant increase in PBzS density occurred in the ovary (P less than 0.02) and uterus (P less than 0.001) at 09:00 h on the day of pro-oestrus as compared to 09:00 h on the day of dioestrus. These changes were associated with an increase in serum oestradiol and progesterone concentrations. The affinity of PBzS in all tissues examined remained unaltered during the oestrous cycle. This study demonstrates that changes associated with the oestrous cycle occur in the density of PBzS in various genital organs.  相似文献   
92.

Background

Fifty random genetically unstudied families (limb-girdle muscular dystrophy (LGMD)/myopathy) were screened with a gene panel incorporating 759 OMIM genes associated with neurological disorders. Average coverage of the CDS and 10 bp flanking regions of genes was 99 %. All families were referred to the Neurosciences Clinic of King Faisal Specialist Hospital and Research Centre, Saudi Arabia. Patients presented with muscle weakness affecting the pelvic and shoulder girdle. Muscle biopsy in all cases showed dystrophic or myopathic changes. Our main objective was to evaluate a neurological gene panel as a first-line diagnostic test for LGMD/myopathies.

Results

Our panel identified the mutation in 76 % of families (38/50; 11 novel). Thirty-four families had mutations in LGMD-related genes with four others having variants not typically associated with LGMD. The majority of cases had recessive inheritance with homoallelic pathogenic variants (97.4 %, 37/38), as expected considering the high rate of consanguinity in the study population. In one case, we detected a heterozygous mutation in DNAJB responsible for LGMD-1E. Our cohort included seven different subtypes of LGMD2. Mutations of DYSF were the most commonly identified cause of disease followed by that in CAPN3 and FKRP. Non-LGMD myopathies were due to mutations in genes associated with congenital disorder of glycosylation (ALG2), rigid spine muscular dystrophy 1 (SEPN1), inclusion body myopathy2/Nonaka myopathy (GNE), and neuropathy (WNK1). Whole exome sequencing (WES) of patients who remained undiagnosed with the neurological panel did not improve our diagnostic yield.

Conclusions

Our neurological panel achieved a high clinical sensitivity (76 %) and is an effective first-line laboratory test in patients with LGMD and other myopathies. This sensitive, cost-effective, and rapid assay significantly assists clinical practice especially in these phenotypically and genetically heterogeneous disorders. Moreover, the application of the American College of Medical Genetics (ACMG) and Association for Molecular Pathology (AMP) guidelines applied in the classification of variant pathogenecity provides a clear interpretation for physicians on the relevance of such findings.
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93.
94.
This study’s objective was to assess a seasonal impact of industrial and sewage waste disposal on water quality of the river upstream Trimu Head. Considering the significance of the river, drain wastewater was analyzed during the summer and the winter seasons from pre-determined locations. Water quality parameters were recorded higher than the maximum permissible limits prescribed by WHO for freshwater bodies. Level of these Physio-chemical variables was higher in the winter due to the least amount of water from domestic sewage. Although some of these parameters indicated sedimentation hitherto the water quality of River Chenab was found very poor due to the pollution bestowed by tributary waste water from drains. Findings of this investigation suggest the importance of continuous monitoring and assessment to improve the water quality of the river. This study provides a baseline data which may be compared to assess any further deterioration in the water quality and may also be used to plan future monitoring and required restoration of habitat for the safe supply of fish to the population of this region.  相似文献   
95.
Abnormal ocular motility is a common clinical feature in congenital cranial dysinnervation disorder (CCDD). To date, eight genes related to neuronal development have been associated with different CCDD phenotypes. By using linkage analysis, candidate gene screening, and exome sequencing, we identified three mutations in collagen, type XXV, alpha 1 (COL25A1) in individuals with autosomal-recessive inheritance of CCDD ophthalmic phenotypes. These mutations affected either stability or levels of the protein. We further detected altered levels of sAPP (neuronal protein involved in axon guidance and synaptogenesis) and TUBB3 (encoded by TUBB3, which is mutated in CFEOM3) as a result of null mutations in COL25A1. Our data suggest that lack of COL25A1 might interfere with molecular pathways involved in oculomotor neuron development, leading to CCDD phenotypes.  相似文献   
96.
The marking of flowers with ephemeral scent is an underappreciated but vital element in the foraging behaviour of social bees. Using observational and experimental data, we tested whether a solitary bee (female Anthophora plumipes) uses scent marking while foraging on flowers of Cerinthe major in Portugal. Females used scent marks with at least two components that differed in their volatility and, furthermore, recognized the marks of different individuals. A very short-term component (<3 min) was attractive, resulting in the observed high level of immediate revisits: this component appeared to be adjusted according to the foraging needs of the moment. A longer-term component (<30 min) was initially repellent and matched the rate of nectar renewal; it, or the response to it, also appeared to be adjusted to the perceived level of nectar reward. There may be even longer-term effects associated with the specific foraging areas of individual bees. Observed differences in the way in which individuals responded to scent marks indicate that they may play a role as part of a dominance or exclusion mechanism among females. Copyright 2001 The Association for the Study of Animal Behaviour.  相似文献   
97.
N-terminal acetylation is a very common post-translational modification, although its role in regulating protein physical properties and function remains poorly understood. α-Synuclein (α-syn), a protein that has been linked to the pathogenesis of Parkinson disease, is constitutively N(α)-acetylated in vivo. Nevertheless, most of the biochemical and biophysical studies on the structure, aggregation, and function of α-syn in vitro utilize recombinant α-syn from Escherichia coli, which is not N-terminally acetylated. To elucidate the effect of N(α)-acetylation on the biophysical and biological properties of α-syn, we produced N(α)-acetylated α-syn first using a semisynthetic methodology based on expressed protein ligation (Berrade, L., and Camarero, J. A. (2009) Cell. Mol. Life Sci. 66, 3909-3922) and then a recombinant expression strategy, to compare its properties to unacetylated α-syn. We demonstrate that both WT and N(α)-acetylated α-syn share a similar secondary structure and oligomeric state using both purified protein preparations and in-cell NMR on E. coli overexpressing N(α)-acetylated α-syn. The two proteins have very close aggregation propensities as shown by thioflavin T binding and sedimentation assays. Furthermore, both N(α)-acetylated and WT α-syn exhibited similar ability to bind synaptosomal membranes in vitro and in HeLa cells, where both internalized proteins exhibited prominent cytosolic subcellular distribution. We then determined the effect of attenuating N(α)-acetylation in living cells, first by using a nonacetylable mutant and then by silencing the enzyme responsible for α-syn N(α)-acetylation. Both approaches revealed similar subcellular distribution and membrane binding for both the nonacetylable mutant and WT α-syn, suggesting that N-terminal acetylation does not significantly affect its structure in vitro and in intact cells.  相似文献   
98.
The chemical industry has come under increasing pressure to make chemical production more eco-friendly and independent to fossil resources. The development of industrial processes based on micro-organisms can especially help to eliminate the use or the generation of hazardous substances and can support the transition from dependence on fossil resources towards real sustainable and eco-safety industrial processes. The biocatalysts are the best solution given by nature that can be used to improve some biotechnological applications. In this research review, we report some peculiar properties of biocatalysts, implicated in a range of metabolic pathways and biotechnological tools.  相似文献   
99.
Leaves of fast‐growing, woody bioenergy crops often emit volatile organic compounds (VOC). Some reactive VOC (especially isoprene) play a key role in climate forcing and may negatively affect local air quality. We monitored the seasonal exchange of VOC using the eddy covariance technique in a ‘coppiced’ poplar plantation. The complex interactions of VOC fluxes with climatic and physiological variables were also explored by using an artificial neural network (Self Organizing Map). Isoprene and methanol were the most abundant VOC emitted by the plantation. Rapid development of the canopy (and thus of the leaf area index, LAI) was associated with high methanol emissions and high rates of gross primary production (GPP) since the beginning of the growing season, while the onset of isoprene emission was delayed. The highest emissions of isoprene, and of isoprene photo‐oxidation products (Methyl Vinyl Ketone and Methacrolein, iox), occurred on the hottest and sunniest days, when GPP and evapotranspiration were highest, and formaldehyde was significantly deposited. Canopy senescence enhanced the exchange of oxygenated VOC. The accuracy of methanol and isoprene emission simulations with the Model of Emissions of Gases and Aerosols from Nature increased by applying a function to modify their basal emission factors, accounting for seasonality of GPP or LAI.  相似文献   
100.
Cells have to maintain stable plasma membrane protein and lipid compositions under normal conditions and to remodel their plasma membranes in response to stimuli. This maintenance and remodeling require that integral membrane proteins at the plasma membrane that become misfolded, because of the relatively harsher extracellular milieu or carbohydrate and amino acid sequence changes, are degraded. We had previously shown that Derlin proteins, required for quality control mechanisms in the endoplasmic reticulum, also localize to endosomes and function in the degradation of misfolded integral membrane proteins at the plasma membrane. In this study, we show that Derlin proteins physically associate with sorting nexins that function in retrograde membrane transport from endosomes to the Golgi apparatus. Using genetic studies in Caenorhabditis elegans and ricin pulse-chase analyses in murine RAW264.7 macrophages, we show that the Derlin-sorting nexin interaction is physiologically relevant. Our studies suggest that at least some integral membrane proteins that are misfolded at the plasma membrane are retrogradely transported to the Golgi apparatus and ultimately to the endoplasmic reticulum for degradation via resident quality control mechanisms.  相似文献   
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