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41.
Vasopressin V1a receptors (V1aR) were found in the cerebellum but their functional role has not been determined. As V1aR are engaged in the central regulation of the cardiovascular system and anxiogenic behavior and their role increases in the heart failure and stress, we decided to find out whether expression of V1aR is altered after myocardial infarction and chronic stressing. RT-PCR and Western blot analysis were performed to determine V1aR mRNA and protein expression in the cerebellum of four groups of rats (control sham-operated, infarcted, chronically stressed and infarcted chronically stressed). The myocardial infarct was produced by left coronary artery ligation, and chronic stressing by exposing the rat for four weeks to different types of mild stressors. The rats were sacrificed four weeks after the myocardial surgery or sham operation. Expressions of V1aR mRNA and protein were significantly lower in the infarcted and infarcted chronically stressed rats than in the sham-operated controls and chronically stressed not infarcted rats. No significant differences were found between the sham-operated controls and chronically stressed rats and between the infarcted rats and infarcted rats exposed to chronic stressing. It is concluded that V1aR mRNA and protein expressions are significantly down-regulated in the rats with the post-infarct heart failure but they are not affected by mild chronic stressing.  相似文献   
42.
Prostate, bladder and kidney cancers remain the most common cancers of the urinary tract. Despite improved primary prevention, detection and treatment, the incidence of age-related cancers of the urinary tract is likely to rise as a result of global population ageing. An association of diet with prostate, bladder and kidney carcinogenesis is plausible since the majority of metabolites, including carcinogens, are excreted through the urinary tract. Moreover, large regional differences in incidence rates of urologic tumours exist throughout the world. These rates change when people relocate to different geographic areas, which is suggestive of a strong environmental influence. As a result of these observations, numerous studies have been conducted to assess the effects of diet and nutritional status in kidney, bladder and prostate carcinogenesis. Here, we review the literature assessing the effect of diet and nutritional status on urological cancer risk, which has attracted the most interest.  相似文献   
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Chronic neutrophilic leukemia (CNL) relates to mutational CSF3R activation with membrane proximal CSF3R mutations such as T618I as driver mutations, but the significance of truncating mutations is not clarified. In CNL, concomitant mutations promote disease progression, but insight into longitudinal acquisition is incomplete. In this study, we investigated the role of co-occurring germline and somatic CSF3R mutations in CNL, and assessed the impact of clonal evolution on transformation to acute leukemia. We employed sequential next generation sequencing and SNP array karyotyping to assess clonal evolution in CNL of early manifestation age based on a 33-year-old patient. Germline vs. somatic mutations were differentiated using a sample from the hair follicle. To investigate a potential predisposition for CNL development and progression by germline CSF3R-W791*, allelic localizations were evaluated. We detected a somatic CSF3R-T618I mutation at 46% variant allele frequency (VAF) at the time of CNL diagnosis, which co-occurred with a CSF3R-W791* truncation at 50% VAF in the germline. Evaluation of allelic localization revealed CSF3R-T618I and W791* on the same allele. A concomitant ASXL1 mutation at 39% VAF increased to 48% VAF upon transformation to mixed phenotype acute leukemia (MPAL), which has both myeloid and lymphoid features. Clonal evolution further involved expansion of the CSF3R double-mutant clone to 90% VAF via copy neutral loss of heterozygosity on chromosome 1p and the emergence of a RUNX1 mutant subclone. Allogeneic transplantation induced complete remission. This study highlights that CNL not only transforms to AML but also to MPAL. The molecular evolution is especially interesting with a CSF3R-W791* mutation in the germline and acquisition of CSF3R-T618I on the same allele compatible with increased susceptibility for mutation acquisition facilitating RUNX1-related clonal transformation.  相似文献   
45.
With the continuing growth of waste sulfur production from the petroleum industry processes, its utilization for the production of useful, low-cost, and environmentally beneficial materials is of primary interest. Elemental sulfur has a significant and established history in the modification of bitumen binders, while the sulfur-containing high-molecular compounds are limited in this field. Herein, we report a novel possibility to utilize the sulfur/organic copolymers obtained via the inverse vulcanization process as modifiers for bitumen binders. Synthesis and thermal characterization (TGA-DSC) of polysulfides derived from elemental sulfur (S8) and unsaturated organic species (dicyclopentadiene, styrene, and limonene) have been carried out. The performance of modified bitumen binders has been studied by several mechanical measurements (softening point, ductility, penetration at 25 °C, frass breaking point, adhesion to glass and gravel) and compared to the unmodified bitumen from the perspective of normalized requirements concerning polymer-modified bitumen. The interaction of bitumen binder with sulfur/organic modifier has been studied by means of FTIR spectroscopy and DSC measurements. The impact of the modification on the performance properties of bitumen has been demonstrated. The bitumen binders modified with sulfur/organic copolymers are in general less sensitive to higher temperatures (higher softening point up to 7 °C), more resistant to permanent deformations (lower penetration depth), and more resistant to aging processes without intrusive deterioration of parameters at lower temperatures. What is more, the modification resulted in significantly higher adhesion of bitumen binders to both glass (from 25% up to 87%) and gravel surfaces in combination with a lower tendency to form permanent deformations (more elastic behavior of the modified materials).  相似文献   
46.
When treating historical beeswax seals, it seems a natural choice to use materials as similar to the original as possible. The properties of analogous recent materials, however, differ from those of the aged ones, not to mention the fact that the exact composition of the particular sealing wax is usually uncertain. In order to obtain the material of desired properties, recent beeswax is often combined with various additives, including petroleum waxes, or even replaced by mixtures based solely on these products. Within this study, the relevant properties of Permulgin 3274, a ceresin-type wax, were compared with the characteristics of recent and historical beeswaxes. The aim was to evaluate its advantages and limitations, in terms of its possible use for the conservation of beeswax seals. The properties studied were comprised of the chemical composition, thermal properties, mechanical properties, possibilities of colour adjustment and ageing properties. Permulgin 3274′s workability was evaluated by conservators from the National Archives in Prague. The results indicate that, from the technological point of view, Permulgin 3274 could be considered a welcome alternative to the use of traditional conservation mixtures.  相似文献   
47.
Poly-ɛ-caprolactone (PCL) is now widely studied in relation to the engineering of bone, cartilage, tendons, and other tissues. Standard histological protocols can destroy the carefully created trabecular and honeycomb-like architecture of PCL scaffolds, and could lead to scaffold fibers swelling, resulting in the displacement or compression of tissues inside the scaffold. The aim of this study was to modify a standard histopathological protocol for PCL scaffold preparation and evaluate it on porous cylindrical PCL scaffolds in a rat model. In 16 inbred Wag rats, 2 PCL scaffolds were implanted subcutaneously to both inguinal areas. Two months after implantation, harvested scaffolds were first subjected to μCT imaging, and then to histopathological analysis with standard (left inguinal area) and modified histopathological protocols (right inguinal area). To standardize the results, soft tissue percentages (STPs) were calculated on scaffold cross-sections obtained from both histopathological protocols and compared with corresponding µCT cross-sections. The modified protocol enabled the assessment of almost 10× more soft tissues on the scaffold cross-section than the standard procedure. Moreover, STP was only 1.5% lower than in the corresponding µCT cross-sections assessed before the histopathological procedure. The presented modification of the histopathological protocol is cheap, reproducible, and allows for a comprehensive evaluation of PCL scaffolds while maintaining their trabecular, honeycomb-like structure on cross-sections.  相似文献   
48.
Malignant melanoma is a high aggressive malignancy in humans and causes 60–80% of deaths from skin cancer. Defect in an intrinsic pathway of apoptosis via overexpression of Mcl-1 is responsible for malignant melanoma development and progression, and also for resistance to chemotherapeutic agents. MIM1 is a specific low molecular Mcl-1 protein inhibitor that is able to induce Mcl-1-dependent cancer cells death. Here, we examined the effect of MIM1 as well as MIM1 and dacarbazine (DTIC) mixture on cell viability, apoptosis, and cell cycle progression in COLO829 melanoma cells. Cell viability was performed by the WST-1 assay. Analysis of apoptosis as well as cell cycle progression was determined by fluorescence image cytometer NucleoCounter NC-3000. The obtained results demonstrated that the MIM1 exhibited high cytotoxicity against melanotic melanoma cells and induced mitochondrial membrane breakdown, GSH depletion, and DNA fragmentation. Additionally, MIM1 enhanced the proapoptotic effect of DTIC toward melanoma cells; furthermore, a mixture of these drugs caused cell cycle arrest at G2/M phase in COLO829 cells. Taken together, these data provide, for the first time, evidence that a low molecular weight Mcl-1 inhibitor—MIM1 may be a promising agent with antitumor and proapoptotic properties toward melanoma cells.  相似文献   
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Torrefaction is one of the methods of thermal treatment of biomass, which allows obtaining a product of better quality in the form of biochar. The aim of the paper was to analyze the possibility of using goldenrod (Solidago canadensis, Solidago gigantea) for the production of biochar. The torrefaction process involved the vegetative and generative parts as well as the whole plant at temperatures of 250 °C and 275 °C, for 3 h. Next, the physicochemical properties of the raw material and biochar were determined, namely moisture content, ash content, volatile matter content, calorific value, and heat of combustion. The bulk density of raw biomass and biochar was also determined. It was found that after biomass torrefaction, the ash content, calorific value, and heat of combustion increased, while volatile matter content decreased. It has been observed that in both the case of raw biomass and biochar, the plant species and the sampled parts have a significant impact on the ash content, volatile matter content, calorific value, and heat of combustion.  相似文献   
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