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101.
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Satam  Shalaka  Satam  Pratik  Pacheco  Jesus  Hariri  Salim 《Cluster computing》2022,25(4):2767-2778
Cluster Computing - The rapid deployment of the Internet of Things (IoT) devices have led to the development of innovative information services, unavailable a few years ago. To provide these...  相似文献   
103.

The objective of this study was to evaluate the effects of different natural ventilation systems and explant types on the growth and volatile compound content of Lippia gracilis cultured in vitro. The treatments consisted of four membrane systems (without membrane, with one, two, and four porous membranes) and two explant types (nodal segments with and without a pair of leaves). The evaluation of growth, photosynthetic pigments and chemical analysis of the volatile fraction were performed at 35 days of cultivation in half strength MS basal medium. Natural ventilation systems significantly influenced the in vitro growth and volatile fraction of L. gracilis. Explants with a pair of leaves obtained the best experimental responses. The natural ventilation system with four membranes provided the best growth parameters and leaf area response of L. gracilis explants with leaves. The photosynthetic pigments decreased with an increase in the number of porous membranes in the culture flask. Variations in the number, content, and profile of volatile compounds under the influence of natural ventilation systems were observed. Major constituents such as ρ-cymene, γ-terpinene, thymol, carvacrol, and E-caryophyllene, regardless of experimental conditions, were identified. The highest carvacrol and thymol contents were observed in plantlets grown in culture flasks with four porous membranes. To maximize the content of carvacrol and thymol from the in vitro culture of L. gracilis, explants with a pair of leaves and four porous membranes in culture flasks are recommended for use.

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104.
The aim of this study was to investigate the daily rhythms of hematological, biochemical and enzymatic parameters of the blood of a nocturnal model of fish (Lophiosilurus alexandri) bred in the laboratory (F1). Thirty-six juveniles were stocked in six tanks of a recirculation aquaculture system for 20 days. The fish were exposed to a light:dark cycle of 12:12 h and were fed 1% of biomass twice a day with commercial diet. The daily rhythms of hematological, biochemical and enzymatic parameters were then measured at six sampling times “zeitgeber time = ZT” at four-hour intervals under light:dark 12:12 h (lights on = ZT0, at 8.00 a.m). No differences were observed to alkaline phosphatase, glucose, cortisol, aspartate aminotransferase, superoxide dismutase, total protein and hematocrit (p > 0.05). However, white blood cell count, Lymphocytes (LYN), Neutrophils (NEU), Eosinophil and Neutrophils to Lymphocytes ratio were significant different between sample times (p < 0.05). Also, a significant difference in alanine transaminase was observed, with a peak of production at nighttime. In contrast, glutathione peroxidase peaked at 8:00. Uric acid, magnesium and Calcium (Ca++) showed statistically significant differences (p < 0.05). A significant difference was observed (p < 0.05), with a peak of albumin at 08:00 and triglycerides at 12:00, while cholesterol was low (p < 0.05) at 08:00 and higher from 12:00 to 04:00. Cosinor analysis revealed also rhythmicity to SOD, UA, Mg and Ca++, ALB and CHO (p < 0.05). In conclusion, the time of day must be considered a key factor when using blood parameters as biomarkers for disease, health and welfare in the L. alexandri aquaculture.  相似文献   
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Alexander disease (AxD) is a rare and fatal neurodegenerative disorder caused by mutations in the gene encoding glial fibrillary acidic protein (GFAP). In this report, a mouse model of AxD (GFAPTg;Gfap+/R236H) was analyzed that contains a heterozygous R236H point mutation in murine Gfap as well as a transgene with a GFAP promoter to overexpress human GFAP. Using label-free quantitative proteomic comparisons of brain tissue from GFAPTg;Gfap+/R236H versus wild-type mice confirmed upregulation of the glutathione metabolism pathway and indicated proteins were elevated in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which had not been reported previously in AxD. Relative protein-level differences were confirmed by a targeted proteomics assay, including proteins related to astrocytes and oligodendrocytes. Of particular interest was the decreased level of the oligodendrocyte protein, 2-hydroxyacylsphingosine 1-beta-galactosyltransferase (Ugt8), since Ugt8-deficient mice exhibit a phenotype similar to GFAPTg;Gfap+/R236H mice (e.g., tremors, ataxia, hind-limb paralysis). In addition, decreased levels of myelin-associated proteins were found in the GFAPTg;Gfap+/R236H mice, consistent with the role of Ugt8 in myelin synthesis. Fabp7 upregulation in GFAPTg;Gfap+/R236H mice was also selected for further investigation due to its uncharacterized association to AxD, critical function in astrocyte proliferation, and functional ability to inhibit the anti-inflammatory PPAR signaling pathway in models of amyotrophic lateral sclerosis (ALS). Within Gfap+ astrocytes, Fabp7 was markedly increased in the hippocampus, a brain region subjected to extensive pathology and chronic reactive gliosis in GFAPTg;Gfap+/R236H mice. Last, to determine whether the findings in GFAPTg;Gfap+/R236H mice are present in the human condition, AxD patient and control samples were analyzed by Western blot, which indicated that Type I AxD patients have a significant fourfold upregulation of FABP7. However, immunohistochemistry analysis showed that UGT8 accumulates in AxD patient subpial brain regions where abundant amounts of Rosenthal fibers are located, which was not observed in the GFAPTg;Gfap+/R236H mice.  相似文献   
107.
Colyophilization or codrying of subtilisin Carlsberg with the crown ethers 18-crown-6, 15-crown-5, and 12-crown-4 substantially improved enzyme activity in THF, acetonitrile, and 1,4-dioxane in the transesterification reactions of N-acetyl-L-phenylalanine ethylester and 1-propanol and that of (+/-)-1-phenylethanol and vinylbutyrate. The acceleration of the initial rate, V(0), ranged from less than 10-fold to more than 100-fold. All crown ethers activated subtilisin substantially, which excludes a specific macrocyclic effect from being responsible. The secondary structure of subtilisin was studied by Fourier-transform infrared (FTIR) spectroscopy. 18-Crown-6 and 15-crown-5 led to a more nativelike structure of subtilisin in the organic solvents employed when compared with that of the dehydrated enzyme obtained from buffer alone. However, the high level of activation with 12-crown-4 where this effect was not observed excluded overall structural preservation from being the primary cause of the observed enzyme activation. The conformational mobility of subtilisin was investigated by performing thermal denaturation experiments in 1,4-dioxane. Although only a small effect of temperature on subtilisin structure was observed for the samples prepared with or without 12-crown-4, both 18-crown-6 and 15-crown-5 caused the enzyme to denature at quite low temperatures (38 degrees C and 56 degrees C, respectively). No relationship between this property and V(0) was evident, but increased conformational mobility of the protein decreased its storage stability. The possibility of a "molecular imprinting" effect was also tested by removing 18-crown-6 from the subtilisin-18-crown-6 colyophilizate by washing. V(0) was only halved as a result of this procedure, an effect insignificant compared with the ca. 80-fold rate enhancement observed prior to washing in THF. This suggests that molecular imprinting is likely the primary cause of subtilisin activation by crown ethers, as recently suggested.  相似文献   
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Circular dichroism and fluorescence spectroscopy have been employed to study the urea unfolding mechanism of a recombinant form of the major core protein of feline immunodeficiency virus (FIV-rp24) and its native tryptophan mutants. The equilibrium denaturation curves indicate the existence of two transitions. The first unfolding transition most likely reflects the denaturation of the carboxy-terminal region of FIV-rp24. Consequently, the second transition, where the changes in fluorescence are produced, should reflect the denaturation of the amino-terminal region. If the intermediate observed upon urea denaturation is an on-pathway species, the data described herein can reflect the sequential and independent loss of structure of the two domains that this type of proteins possesses.  相似文献   
110.
In 1997, an epizootic in Taiwan, Province of China, was caused by a type O foot-and-mouth disease virus which infected pigs but not cattle. The virus had an altered 3A protein, which harbored a 10-amino-acid deletion and a series of substitutions. Here we show that this deletion is present in the earliest type O virus examined from the region (from 1970), whereas substitutions surrounding the deletion accumulated over the last 29 years. Analyses of the growth of these viruses in bovine cells suggest that changes in the genome in addition to the deletion, per se, are responsible for the porcinophilic properties of current Asian viruses in this lineage.  相似文献   
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