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41.
Demonstrations of both pro-apoptotic and pro-survival abilities of Fas (TNFRSF6/CD95/APO-1) have led to a shift from the exclusive “Fas apoptosis” to “Fas multisignals” paradigm and the acceptance that Fas-related therapies face a major challenge, as it remains unclear what determines the mode of Fas signaling. Through protein evolution analysis, which reveals unconventional substitutions of Fas tyrosine during divergent evolution, evolution-guided tyrosine-phosphorylated Fas proxy, and site-specific phosphorylation detection, we show that the Fas signaling outcome is determined by the tyrosine phosphorylation status of its death domain. The phosphorylation dominantly turns off the Fas-mediated apoptotic signal, while turning on the pro-survival signal. We show that while phosphorylations at Y232 and Y291 share some common functions, their contributions to Fas signaling differ at several levels. The findings that Fas tyrosine phosphorylation is regulated by Src family kinases (SFKs) and the phosphatase SHP-1 and that Y291 phosphorylation primes clathrin-dependent Fas endocytosis, which contributes to Fas pro-survival signaling, reveals for the first time the mechanistic link between SFK/SHP-1-dependent Fas tyrosine phosphorylation, internalization route, and signaling choice. We also demonstrate that levels of phosphorylated Y232 and Y291 differ among human cancer types and differentially respond to anticancer therapy, suggesting context-dependent involvement of Fas phosphorylation in cancer. This report provides a new insight into the control of TNF receptor multisignaling by receptor phosphorylation and its implication in cancer biology, which brings us a step closer to overcoming the challenge in handling Fas signaling in treatments of cancer as well as other pathologies such as autoimmune and degenerative diseases.  相似文献   
42.
This study was designed to investigate the effects of starvation and re‐feeding cycles on the growth performance and body chemical composition of Oncorhynchus mykiss juveniles. A total of 360 juveniles with initial mean weights (IW) of 8.46 ± 0.07 g (n = 360) were stocked into 400‐L tanks in triplicate for each group, with 30 juveniles per tanks. The control group received regular feed, as is the common practice. The three other groups were periodically starved: 1 day starvation followed by 6 days re‐feeding (S1), 2 days starvation followed by 5 days re‐feeding (S2) and 3 days starvation followed by 4 days re‐feeding (S3). The experiment lasted for 10 weeks, over the course of which the water flow rate was 4 L min?1 and the water quality parameters determined as: temperature 14.4 ± 1.1°C, oxygen 8.2 ± 0.4 mg L?1 and pH 7.5 ± 0.2. At the end of the study, S1 had the best growth performance (final weight, specific growth rate, average daily growth) of all test groups (P < 0.05). The lowest daily feed intake (DFI) and growth performance parameters were observed in S3 (P < 0.05), while protein efficiency ratio (PER), net protein utilization (NPU) and lipid efficiency ratio (LER) were higher in the S3 fish group than in the other groups (P < 0.05). Whole body protein and lipid contents were highest in S1 fish. The hepatosomatic index (HSI) and viscerosomatic index (VSI) were significantly different among groups (P < 0.05). Feed conversion ratio (FCR) was significantly lower in starvation groups S1, S2 and S3 than in the control (P < 0.05). Compensation coefficient (CC) values were higher than 1 in all starvation groups. The concluding indicate that rainbow trout exposed to 1 and 2 days of starvation in week cycles could achieve over compensation compared to the control. Additionally, partial growth compensation and improved feed utilization could be achieved in a starvation group within 3 days in a week, by beginning with the juvenile size over a 10‐week experimental period.  相似文献   
43.

The cooperation of Bacillus subtilis strain DKT and Comamonas testosteroni KT5 was investigated for biofilm development and toluenes and chlorobenzenes degradation. Bacillus subtilis strain DKT and C. testosteroni KT5 were co-cultured in liquid media with toluenes and chlorobenzenes to determine the degradation of these substrates and formation of dual-species biofilm used for the degradation process. Bacillus subtilis strain DKT utilized benzene, mono- and dichlorinated benzenes as carbon and energy sources. The catabolism of chlorobenzenes was via hydroxylation, in which chlorine atoms were replaced by hydroxyl groups to form catechol, followed by ring fission via the ortho-cleavage pathway. The investigation of the dual-species biofilm composed of B. subtilis DKT and C. testosteroni KT5 (a toluene and chlorotoluene-degrading isolate with low biofilm formation) showed that B. subtilis DKT synergistically promoted C. testosteroni KT5 to develop biofilm. The bacterial growth in dual-species biofilm overcame the inhibitory effects caused by monochlorobenzene and 2-chlorotoluene. Moreover, the dual-species biofilm showed effective degradability toward the mixture of these substrates. This study provides knowledge about the commensal relationships in a dual-culture biofilm for designing multispecies biofilms applied for the biodegradation of toxic organic substrates that cannot be metabolized by single-organism biofilms.

  相似文献   
44.
Susceptibility of Asian corn borer (ACB), Ostrinia furnacalis (Guenée) to Bacillus thuringiensis (Bt) Cry1Ab protein was studied between 2015 and 2016 with 11 ACB populations, collected from various geographical regions in Vietnam. A concentration range of Cry1Ab from 0.20 to 26.10 ng/cm2 of diet was evaluated against F1 ACB neonates using diet surface-overlay bioassays. Mortality data was recorded daily until seven days after infestation. Growth inhibition was recorded at the end of seven days. The median lethal concentration (LC50) varied ≈3-fold among the different populations, ranging from 0.58 to 1.83 ng/cm2 of diet with an overall mean of 0.86 ng/cm2 of diet. Even the lowest concentration of 0.20 ng/cm2 caused 73.53% growth inhibition. >90% growth inhibition was achieved at 0.82 ng/cm2 or higher concentrations. The results reflect natural variation in Bt susceptibility among ACB populations rather than variation caused by prior exposure to selection pressures. LC99 value (17.26 ng/cm2) was generated by pooling mortality data across different populations. The upper fiducial limit of LC99 (24.38 ng/cm2) could be a potential diagnostic dose for future resistance monitoring programs. The findings from this study suggest that ACB populations in Vietnam are highly susceptible to Cry1Ab protein. This is the first report of Cry1Ab susceptibility of different ACB populations in Vietnam and will serve as a baseline for future resistance monitoring work.  相似文献   
45.
Atopic dermatitis (AD) is a cutaneous disease resulting from a defective barrier and dysregulated immune response. The severity scoring of atopic dermatitis (SCORAD) is used to classify AD. Noninvasive imaging approaches supplementary to SCORAD were investigated. Cr:forsterite laser‐based microscopy was employed to analyze endogenous third‐harmonic generation (THG) and second‐harmonic generation (SHG) signals from skin. Imaging parameters were compared between different AD severities. Three‐dimensional reconstruction of imaged skin layers was performed. Finally, statistic models from quantitative imaging parameters were developed for predicting disease severity. Our data demonstrate that THG signal intensity of lesional skin in AD were significantly increased and was positively correlated with AD severity. Characteristic gray level co‐occurrence matrix (GLCM) values were observed in more severe AD. In the 3D reconstruction video, individual dermal papilla and obvious fibrosis in the upper papillary dermis were easily identified. Our estimation models could predict the disease severity of AD patients with an accuracy of nearly 85%. The THG signal intensity and characteristic GLCM patterns are associated with AD severity and can serve as quantitative predictive parameters. Our imaging approach can be used to identify the histopathological changes of AD objectively, and to complement the SCORAD index, thus improving the accuracy of classifying AD severity.   相似文献   
46.
Single-use technologies, in particular disposable bioreactor bags, have become integral within the biopharmaceutical community. However, safety concerns arose upon the identification of toxic leachable compounds derived from the plastic materials. Although the leachable bis(2,4-di-tert-butylphenyl)-phosphate (bDtBPP) has been previously shown to inhibit CHO cell growth, it is critical to determine if other compounds like this are still present in subsequent generations of films for industrial application. This study compares the performance of CHO cells, CHO-K1, and CHO-DP12, cultured in media conditioned in an older single-use bioreactor (SUB) film (F-1) and a newer generation film (F-2) from the same vendor. CHO cells cultured in media conditioned for 7 days in the F-1 film demonstrated significantly reduced growth and antibody productivity profiles when compared to controls and media conditioned for the same time period in the newer F-2 film. Proteomic profiling of CHO cells cultured in the F-1 conditioned media identified differentially expressed proteins involved in oxidative stress response as well as compromised ATP synthesis. These potentially metabolically compromised cells exhibited reduced oxidative phosphorylation activity as well as lower glycolytic metabolism, characteristic of slower growing cells. Nonvolatile and metal leachables analysis of film extracts by LC–MS revealed a reduction in the abundance of the analyzed leachates from F-2 films when compared to F-1 films including bDtBPP, potentially explaining improved CHO cell growth in F-2 conditioned media. Furthermore, in vitro endocrine disruptor testing of the known leachable revealed this molecule to possess the potential to act as an androgen antagonist. This study demonstrates an improvement in the materials composition used in modern generations of SUBs for safe application in the bioprocess.  相似文献   
47.
A series of Mn2+-doped zinc germinate ZGO:xMn2+ (x = 0–0.05) nanorods was synthesized successfully using a hydrothermal method. XRD revealed that crystal phases of the ZGO:xMn2+ were rhombohedral and in the R-3 space group. The Williamson–Hall equation was also used to explain the strain, nanocrystalline size, and stacking fault. Green LEDs were successfully fabricated by coating ZGO:Mn2+ nanorods onto UV-LED chips. For high color purity, CIE of the fabricated green LEDs were (0.2404, 0.5428), which made this material a promising candidate for fabrication of UV-based green LEDs.  相似文献   
48.
Magnetoreception is the ability of organisms to perceive magnetic fields in the surrounding environment and changes in its properties such as field direction, intensity and gradient, where the effect on organisms can manifest as an array of reactions. As the magnetic sense is found in many taxa, both evolutionarily young and old, it can be assumed that magnetoreception came into existence as one of the first sensory systems. Many studies on the effect of magnetic fields on fishes have considered both fishes that migrate for long distances and those that are more or less sedentary. Research has focused on tracing the perception of the geomagnetic field by fishes and understanding magnetic fields that are smaller and larger than the ambient Earth's geomagnetic field. The question of the effect of magnetic fields of values higher than the Earth's is gaining importance with the increasing effect of anthropogenic magnetic and electromagnetic fields in aquatic ecosystems. This review draws together the results of studies on the effect and reception of natural and human-generated magnetic fields on fishes at various stages of ontogeny, chronologically arranged from gametes, through embryonic development, embryonic and larval motor function, directional reactions of embryos and larvae, orientation of fishes, to the mechanisms of magnetic field reception. The present state of knowledge indicates a common nature of effect on various ontogenetic stages of fishes. However, understanding of the mechanisms of magnetic sense in fishes and its relevance for ecological outcomes highlights that further progress requires more detailed research.  相似文献   
49.
Background:Orcinol-β-D-glucoside, which is also known as orcinol glucoside, is a major phenolic glucoside compound in the rhizome of the Curculigo orchioides Gaertn. This compound has many medicinal properties such as being antioxidant, immunomodulatory, antiosteoporosis, stress relief, antidepressant, etc.Methods:Determination of reducing sugar content by Bertrand’s method, determination of lipid content by Soxhlet method, determination of vitamin C content by iodine titration, determination of enzyme activity catalase by titration with KMnO4. Quantification of Orcinol-β-D-glucoside was conducted by HPLC analysis.Results:The Orcinol-β-D-glucoside of C. orchioides in Thuy Bang mountain was highest. Besides, the content of reducing sugars, vitamin C, enzyme catalase, and lipids of C. orchioides differed significantly among sites. In which, the reducing sugar and vitamin C of C. orchioides in Ngu Binh mountain was highest. Whereas, enzyme catalase was also highest in Thuy Bang mountain. However, the lipid content of C. orchioides was also highest in Huong Tho mountain.Conclusion:The result will contribute to providing the scientific basis for the selection of breeding, planting, development of C. orchioides in Thua Thien Hue province, as well as other provinces in Vietnam and opening new research directions for applications in the future.Key Words: Antioxidants, Hypoxidaceae, Medicinal Plants, Vietnam  相似文献   
50.
Affinity Gel-UDP was utilized to purify GlcNAc:beta1,4Gal/GalNAc transferases (Ts) from human lymphoma spleen, ovarian tumor, and ovarian cancer sera. Mn(2+) was found to be an absolute requirement for activity. Two molecular species containing both beta1,4Gal/GalNAc-T activities were discernible when the purified ovarian tumor microsomal enzyme was subjected to Sephacryl S-100 HR column chromatography as well as native polyacylamide gel-electrophoresis. Acceptor specificity studies of the affinity-purified lymphoma spleen and ovarian tumor microsomal enzymes and the conventionally purified, as well as the cloned, bovine milk GlcNAc:beta1,4Gal-Ts using a number of synthetic acceptors showed that the beta(1,6)-linked GlcNAc moiety to alpha-GalNAc was the most efficient acceptor. As compared to the purified milk enzyme, the recombinant form exhibited sixfold GlcNAc:beta1,4 GalNAc-T activity and up to eightfold GlcNAc6SO3beta-:beta1,4Gal-T activity. Further, the recombinant enzyme catalyzed the transfer of GalNAc to the terminal beta-linked GlcNAc6SO3 moiety. Alpha-lactalbumin (alpha-LA) inhibited up to 85%, the transfer of Gal to the GlcNAc moiety linked either to Man or GlcNAc. On the contrary, alpha-LA had no significant influence on the transfer of GalNAc to the above acceptors. alpha-LA had no appreciable effect on the recombinant enzyme, except for the transfer of Gal or GalNAc to Glc. Both alpha- and beta-glucosides, as well as alpha-N-acetylglucosaminide, did not serve as acceptors.  相似文献   
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