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141.
Mutations in the valosin containing protein (VCP) gene cause hereditary Inclusion body myopathy (hIBM) associated with Paget disease of bone (PDB), frontotemporal dementia (FTD), more recently termed multisystem proteinopathy (MSP). Affected individuals exhibit scapular winging and die from progressive muscle weakness, and cardiac and respiratory failure, typically in their 40s to 50s. Histologically, patients show the presence of rimmed vacuoles and TAR DNA-binding protein 43 (TDP-43)-positive large ubiquitinated inclusion bodies in the muscles. We have generated a VCPR155H/+ mouse model which recapitulates the disease phenotype and impaired autophagy typically observed in patients with VCP disease. Autophagy-modifying agents, such as rapamycin and chloroquine, at pharmacological doses have previously shown to alter the autophagic flux. Herein, we report results of administration of rapamycin, a specific inhibitor of the mechanistic target of rapamycin (mTOR) signaling pathway, and chloroquine, a lysosomal inhibitor which reverses autophagy by accumulating in lysosomes, responsible for blocking autophagy in 20-month old VCPR155H/+ mice. Rapamycin-treated mice demonstrated significant improvement in muscle performance, quadriceps histological analysis, and rescue of ubiquitin, and TDP-43 pathology and defective autophagy as indicated by decreased protein expression levels of LC3-I/II, p62/SQSTM1, optineurin and inhibiting the mTORC1 substrates. Conversely, chloroquine-treated VCPR155H/+ mice revealed progressive muscle weakness, cytoplasmic accumulation of TDP-43, ubiquitin-positive inclusion bodies and increased LC3-I/II, p62/SQSTM1, and optineurin expression levels. Our in vitro patient myoblasts studies treated with rapamycin demonstrated an overall improvement in the autophagy markers. Targeting the mTOR pathway ameliorates an increasing list of disorders, and these findings suggest that VCP disease and related neurodegenerative multisystem proteinopathies can now be included as disorders that can potentially be ameliorated by rapalogs.  相似文献   
142.
Green synthesis of selenium nanoparticles (SeNPs) was achieved by a simple biological procedure using the reducing power of fenugreek seed extract. This method is capable of producing SeNPs in a size range of about 50–150 nm, under ambient conditions. The synthesized nanoparticles can be separated easily from the aqueous sols by a high-speed centrifuge. These selenium nanoparticles were characterized by UV–Vis spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and elemental analysis by X-ray fluorescence spectrometer (XRF). Nanocrystalline SeNPs were obtained without post-annealing treatment. FTIR spectrum confirms the presence of various functional groups in the plant extract, which may possibly influence the reduction process and stabilization of nanoparticles. The cytotoxicity of SeNPs was assayed against human breast-cancer cells (MCF-7). It was found that SeNPs are able to inhibit the cell growth by dose-dependent manner. In addition, combination of SeNPs and doxorubicin shows better anticancer effect than individual treatments.  相似文献   
143.
The hematoxylin and eosin stain is the most common method used in anatomic pathology, yet it is a method about which technologists ask numerous questions. Hematoxylin is a natural dye obtained from a tree originally found in Central America, and is easily converted into the dye hematein. This dye forms coordination compounds with mordant metals, such as aluminum, and the resulting lake attaches to cell nuclei. Regressive formulations contain a higher concentration of dye than progressive formulations and may also contain a lower concentration of mordant. The presence of an acid increases the life of the solution and in progressive solutions may also affect selectivity of staining. An appendix lists more than 60 hemalum formulations and the ratio of dye to mordant for each.  相似文献   
144.
Biological Invasions - Assessing the impacts of alien plant species is scientifically important and critical for supporting invasion-related policies. Generic Impact Scoring System (GISS) and...  相似文献   
145.

Objective

Infancy is a critical period during which rapid growth potentially programs future disease risk. Identifying the modifiable determinants of growth is therefore important. To capture the complexity of infant growth, we modeled growth trajectories from birth to six months in order to compare the genetic and environmental influences on growth trajectory parameters with single time-point measures at birth, three and six months of age.

Methods

Data were from Gemini, a population sample of 2402 UK families with twins. An average 10 weight measurements per child made by health professionals were available over the first six months. Weights at birth, three and six months were identified. Longitudinal growth trajectories were modeled using SITAR utilizing all available weight measures for each child. SITAR generates three parameters: size (characterizing mean weight throughout infancy), tempo (indicating age at peak weight velocity (PWV)), and velocity (reflecting the size of PWV). Genetic and environmental influences were estimated using quantitative genetic analysis.

Results

In line with previous studies, heritability of weight at birth and three months was low (38%), but it was higher at six months (62%). Heritability of the growth trajectory parameters was high for size (69%) and velocity (57%), but low (35%) for tempo. Common environmental influences predominated for tempo (42%).

Conclusion

Modeled growth parameters using SITAR indicated that size and velocity were primarily under genetic influence but tempo was predominantly environmentally determined. These results emphasize the importance of identifying specific modifiable environmental determinants of the timing of peak infant growth.  相似文献   
146.
Invasive plants pose substantial threats to protected areas globally. Although management can limit impacts, spread and reinvasion from neighbouring areas into protected areas are a major and an on‐going problem for land managers. However, identifying the main sources of propagules and the dimensions of invasion pathways is challenging. This study used population genetic markers [inter simple sequence repeats (ISSRs) and amplified fragment length polymorphisms (AFLPs)] to infer the source(s) of re‐colonization and dispersal patterns for a typical invader of riparian and terrestrial habitats (Lantana camara) along the Sabie‐Sand catchment, one of the most important river systems flowing into and across South Africa’s flagship protected area, the Kruger National Park (KNP). Results indicate that populations located along the lower reaches of the Sabie and Sand tributaries harboured substantially higher genetic diversity than those in the upper Sabie catchment. Bayesian assignments indicated that the upper Sabie tributary contributed far fewer propagules than the Sand tributary to the lower Sabie River. Current invasion patterns are due to a combination of a major flood event in 2000 and differences in the degree to which the upstream reaches were managed after the flooding. The major flood of 2000 effectively cleared lantana from the riparian areas. However, whereas on‐going management efforts against riparian species in the KNP have been effective, rendering the upper Sabie relatively clear of lantana, only a small part of the Sand tributary falls under jurisdiction of the KNP and has received consistent management attention. The reinvasion of the lower Sabie in the KNP was therefore almost entirely by propagules from the Sand tributary. The study highlights the important role that molecular tools can play in determining dispersal dynamics and directing invasive species management. For invasive plant species that invade both riparian habitats and landscapes away from rivers in protected areas, such as lantana, management must focus on all major sources of propagules to limit reinvasion.  相似文献   
147.
Abstract: Nautiloids of the superfamily Rutoceratoidea from the late Emsian (late Early Devonian) of the Prague Basin (Czech Republic) are commented upon. Species recognized include the hercoceratids Hercoceras mirum, H.? transiens, Ptenoceras proximum, P. nudum, P. minusculum and Anomaloceras anomalum, as well as the rutoceratids Adelphoceras bohemicum, Homoadelphoceras devonicans, Pseudorutoceras bolli and Goldringia? devonicans. In addition, four new species are described: Parauloceras regulare sp. nov., Roussanoffoceras chlupaci sp. nov., Otomaroceras sp. nov. and Goldringia sp. nov. Morphology and distribution patterns of Pragian and late Emsian rutoceratoid faunas from the Prague Basin are compared. They show that an increased diversity was accompanied by a higher level of specialization of rutoceratoids, which manifested itself in low abundance, increased facies dependence and greater variation in shell size during the Early Devonian. The evolution of sculpture and a contracted aperture, both regarded as protective adaptive features, was also examined, but no adaptive trend towards more pronounced sculpture and constriction of the aperture was found to have occurred in the Early Devonian. A more distinctive sculpture was, however, observed in shallow‐water assemblages of P. proximum in comparison with deeper‐water faunules, and two additional cephalopod species were examined in order to obtain comparative data. The presence of distinct sculpture patterns in coeval shallow‐ and deeper‐water assemblages suggests limited migration between them and consequently reflects some degree of territoriality in Devonian nautiloids. New data on early shell development in P. proximum are presented. During the Chote? Event, rutoceratoid generic diversity dropped dramatically, one family became extinct and the Early Devonian diversification of the group came to an end. The recovery of nautiloid faunas was slower than that of other cephalopods and associated, unrelated invertebrates. The absence of change in abundance patterns between Pragian and late Emsian rutoceratoid faunas, i.e. prior to and subsequent to ammonoid radiation, suggests that the appearance and radiation of the latter group in the early Emsian did not affect the structure of nautiloid assemblages, i.e. these two clades did not occupy the same niches.  相似文献   
148.
149.
Large-scale transient expression in mammalian cells is a rapid protein production technology often used to shorten overall timelines for biotherapeutics drug discovery. In this study we demonstrate transient expression in a Chinese hamster ovary (CHO) host (ExpiCHO-S™) cell line capable of achieving high recombinant antibody expression titers, comparable to levels obtained using human embryonic kidney (HEK) 293 cells. For some antibodies, ExpiCHO-S™ cells generated protein materials with better titers and improved protein quality characteristics (i.e., less aggregation) than those from HEK293. Green fluorescent protein imaging data indicated that ExpiCHO-S™ displayed a delayed but prolonged transient protein expression process compared to HEK293. When therapeutic glycoproteins containing non-Fc N-linked glycans were expressed in transient ExpiCHO-S™, the glycan pattern was unexpectedly found to have few sialylated N-glycans, in contrast to glycans produced within a stable CHO expression system. To improve N-glycan sialylation in transient ExpiCHO-S™, we co-transfected galactosyltransferase and sialyltransferase genes along with the target genes, as well as supplemented the culture medium with glycan precursors. The authors have demonstrated that co-transfection of glycosyltransferases combined with medium addition of galactose and uridine led to increased sialylation content of N-glycans during transient ExpiCHO-S™ expression. These results have provided a scientific basis for developing a future transient CHO system with N-glycan compositions that are similar to those profiles obtained from stable CHO protein production systems. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2724, 2019  相似文献   
150.
We report production of chlorophyll f and chlorophyll d in the cyanobacterium Chlorogloeopsis fritschii cultured under near-infrared and natural light conditions. C. fritschii produced chlorophyll f and chlorophyll d when cultured under natural light to a high culture density in a 20 L bubble column photobioreactor. In the laboratory, the ratio of chlorophyll f to chlorophyll a changed from 1:15 under near-infrared, to an undetectable level of chlorophyll f under artificial white light. The results provide support that chlorophylls f and d are both red-light inducible chlorophylls in C. fritschii.  相似文献   
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