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131.
This study was conducted to investigate the effect of katuk (Sauropus androgynus L. Merr) on growth, non-specific immune and diseases resistance against Vibrio alginolyticus in grouper (Epinephelus coioides). Grouper juveniles (mean weight 10.97 ± 1.99 g, and length 9.67 ± 0.33 cm) were separated into four groups and cultivated in 100-L tank. Each group was fed with diets containing 0, 1.0, 2.5 and 5.0 g/kg herbs diet twice daily. Fish were sampled for non-specific immune parameters at 0, 1, 2, 4, 7, 14 and 30 days. Results showed that fish received S. androgynus at 1.0 and 2.5 g/kg diets affected the growth and non-specific immune responses. Weight gain, specific growth rate, respiratory burst activity, phagocytosis and reactive oxygen species significantly increased in fish administered with 1.0 and 2.5 g/kg S. androgynus diets. The mortality rate after V. alginolyticus challenge decreased in fish fed with 1.0 g/kg S. androgynus extract. Thus, this study indicated that administration of grouper with S. androgynus supplemented diets can affect the growth performances, diseases resistance and enhances non-specific immune responses.  相似文献   
132.
Batatasin-III (3,3′-dihydroxy-5-methoxybibenzyl) produced by Empetrum hermaphroditum has been identified as the main metabolite responsible for the chemical interference exerted by the shrub on the surrounding vegetation in the boreal forest of northern Sweden. In earlier studies, batatasin-III has been found to be present in both soil and soil solutions. However, to understand the actual mechanisms by which batatasin-III may interact, we need to know more about the fate and behaviour of the compound in soil. In order to achieve this, we firstly evaluated the efficiency of different extraction methods in recovering batatasin-III from Empetrum humus and found that the highest yield was obtained using ethyl acetate (6.57 ± 20 μg g−1 HDM, least square mean ± SE). In contrast, no detectable amounts of batatasin-III were obtained when extracting the humus with distilled water, 0.125 M citric acid or 0.05 M NaOH. Secondly, we performed a series of experiments in which the recovery of batatasin-III was determined from humus samples exposed to different treatments. In summary, the recovery of batatasin-III was found to be initially strongly dependent on humus type (i.e. humus collected from under a cover of Empetrum, Vaccinium or forest herbs) as well as the temperature and the length of the incubation period. The amount of recovered batatasin-III was in general highest from the Empetrum humus and lowest from the herb humus, contrary to our hypothesis that microorganisms might be better adapted to batatasin-III in humus of the Empetrum origin than in humus of other origin. Regardless of humus type, the recovery was generally higher at +2 °C than at +18 °C suggesting that microbial degradation of batatasin-III did occur. However, when the recovery of batatasin-III from sterile and non-sterile humus was compared, microbial degradation was found to be of minor importance. In addition, no phenolic degradation products of batatasin-III were detected after batatasin-III had been added to non-sterile humus. The obtained results suggest that batatasin-III, when released into humus, becomes physically trapped by organic matter and metabolized by soil microbes to a less extent.  相似文献   
133.
Global species range dynamics are intrinsically influenced by the interplay between human activities and climate compatibility. Snowflake coral (Carijoa riisei) is a soft octacoral species that belongs to the family Clavulariidae and can rapidly grow to colonise new habitats. This species has successfully colonised numerous habitats, displacing native species and disrupting the ecological balance in the introduced habitats. Recent investigations into species invasions in aquatic ecosystems suggest that anthropogenic activities and climate change will accelerate the introduction, establishment, and spread of invasive species to new habitats. In this study, we utilised ensemble species distribution modelling to investigate shifts in the invasive potential of Snowflake coral in current and future climatic settings on a global scale. Future distribution was forecasted using four Representative Concentration Pathways (RCPs 2.6, 4.5, 6.0, and 8.5) across two periods (2040–2050 and 2090–2100). The results accurately predicted the known distributional range of the species. Temperature, distance to the port, and bathymetry were identified as the three most significant predictor variables. The low and medium habitat suitability regions increased in all scenarios and periods. In the high habitat suitability category, only RCP 4.5 and RCP 6.0 in the 2090–2100 period exhibited an increase in percentage area. Under the worst-case climate scenario, RCP 8.5 (2090–2100), the high-suitability regions displayed a surprising decline in area percentage, which can be attributed to the temperature thresholds of the species. Our findings indicate that the species has a greater potential to spread under current climatic conditions than previously reported, and its expansion may further accelerate in the future. This highlights the urgent need for more intensive surveys employing advanced detection tools and the implementation of proactive management measures to protect vulnerable ecosystems that could be impacted by this species.  相似文献   
134.
《Genomics》2022,114(4):110401
BackgroundTreatment of lung cancer is getting more personalized nowadays and medical practitioners are moving away from conventional histology-driven empirical treatments, platinum-based chemotherapy, and other invasive surgical resections and have started adopting alternate therapies in which therapeutic targets are patient's molecular oncogenic drivers.AimThe aim of the current study is to extract meaningful information from the online somatic mutation data (retrieved from cBioPortal) of 16 most significantly mutated oncogenes in non-small-cell lung cancer (NSCLC), namely EGFR, NRAS, KRAS, HER2 (ERBB2), RET, MET, ROS1, FGFR1, BRAF, AKT1, MEK1 (MAP2K1), PIK3CA, PTEN, DDR2, LKB1 (STK11) and ALK, for improving our understanding of the pathobiology of the lung cancer that can aid decision-making on critical clinical and therapeutic considerations.MethodsUsing an integrated approach comprising 4 steps, the oncogenic potential of 661 missense non-synonymous single nucleotide polymorphisms (nsSNPs) in 16 genes was ascertained using 2059 NSCLC (1575 lung adenocarcinomas, 484 lung squamous cell carcinomas) patients' online mutation data. The steps used comprise sequence/structure homology-based prediction, scoring of conservation of mutated residues and positions, prediction of resulting molecular and functional consequences using machine-learning and structure-guided approach.ResultsOut of a total of 661 nsSNPs analyzed, a set of 29 nsSNPs has been identified as conserved high confidence mutations in 10 of 16 genes relevant to the under study. Out of 29 conserved high confidence nsSNPs, 4 nsSNPs (EGFR N1094Y, BRAF M620I, DDR2 R307L, ALK P1350T) have been found to be putative novel rare genetic markers for NSCLC.ConclusionsThe current study, the first of its kind, has provided a list of deleterious non-synonymous somatic mutations in a selected pool of oncogenes that can be considered as a promising target for future drug design and therapy for patients with lung adenocarcinomas and squamous cell carcinomas.  相似文献   
135.
Cellulolytic myxobacterium Sorangium can efficiently degrade cellulose materials. The cellulolytic activities are linked to cellular surfaces and organized into a large complex, which is presumed to be the protuberant structures that were found on the growing cell surfaces. The separated cellulolytic complex was determined to be 1000–2000 kDa from gel chromatogram, and contained at least cellulase and xylanase activities. The separated complex was unstable and could release smaller fractions when they stored in solution at refrigerator. There were more than ten bands on SDS-PAGE after the complex was heat-treated with SDS. The HPLC chromatogram of the complex on DIOL-300 column also supports the result.  相似文献   
136.
Studies on vulnerability, a fairly new research paradigm inspired by global environmental change, are expanding to support scientific decision-making for developing sustainable, resilient territorial space at the regional level. The goal of this research is to reveal the vulnerability of a human-environment coupled system and its interaction mechanisms amidst a changing environment. This study started with the vulnerability scoping diagram (VSD) conceptual model and built up a research framework of territorial spatial vulnerability according to the three structural elements of ecological protection, agricultural production and urban construction. Following the requirements for intelligent computing, we introduced particle swarm optimization and BP neural network learning algorithms to evaluate the vulnerability of Shenzhen's territory. We also introduced flow cytometry to analyze the mechanism of Shenzhen's territorial spatial vulnerability driven by human and natural forces. The results showed that the territorial spatial vulnerability of Shenzhen was low under various functional orientations. Among them, ecological protection-oriented territorial spatial vulnerability was high in the west and low in the east and followed an inverted U-shaped trend in the north-south direction. Agricultural production-oriented territorial spatial vulnerability was high in the east and low in the west, high in the north and low in the south. Urban construction-oriented territorial spatial vulnerability was high in the west and low in the east, high in the north and low in the south. Under the complex orientation of the gigantic human-environment coupled system, the vulnerability of territory was symmetrical and balanced in the north-south direction and fluctuated with an overall declining trend in the east-west direction. In vulnerability, ecological protection, agricultural production and urban construction systems independently accounted for 35.642%, 38.209%, and 26.149% of the territorial spatial vulnerability, respectively.  相似文献   
137.
The phytochemical investigation of Salacia impressifolia (Miers) A. C. Smith led to the isolations of 15 compounds, including triterpene quinonemethides, which are employed as the common characteristic constituents of the Celastraceae family. Pristimerin (9) and tingenone (12) were isolated as the main compounds in the studied tissues. Additionally, friedelane, lupane, oleanane, and ursane triterpenoids were also isolated. All of them were isolated from this plant for the first time.  相似文献   
138.
We have previously observed that in common carp (Cyprinus carpio), administration of β-glucan (MacroGard®) as feed additive leads to a lower expression of pro-inflammatory cytokines suggesting that this immunostimulant may be preventing an acute and potentially dangerous response to infection, particularly in the gut. However, in general, mechanisms to detect and eliminate pathogens must also be induced in order to achieve an efficient clearance of the infection. Protection against viral diseases acquired through β-glucan-supplemented feed has been extensively reported for several experimental models in fish but the underlining mechanisms are still unknown. Thus, in order to better characterize the antiviral action induced by β-glucans in fish, MacroGard® was administered daily to common carp in the form of supplemented commercial food pellets. Carp were fed for a period of 25 days prior to intra-peritoneal injection with polyinosinic:polycytidylic acid (poly(I:C)), a well-known double-stranded RNA mimic that triggers a type-I interferon (IFN) response. Subsequently, a set of immune related genes, including mx, were analysed by real-time PCR on liver, spleen, head kidney and mid gut tissues. Results obtained confirmed that treatment with β-glucan alone generally down-regulated the mRNA expression of selected cytokines when compared to untreated fish, while mx gene expression remained stable or was slightly up-regulated. Injection with poly(I:C) induced a similar down-regulated gene expression pattern for cytokines in samples from β-glucan fed fish. In contrast, poly(I:C) injection markedly increased mx gene expression in samples from β-glucan fed fish but hardly in samples from fish fed control feed. In an attempt to explain the high induction of mx, we studied Toll-like receptor 3 (TLR3) gene expression in these carp. TLR3 is a prototypical pattern recognition receptor considered important for the binding of viral double-stranded RNA and triggering of a type-I IFN response. Through genome data mining, two sequences for carp tlr3 were retrieved (tlr3.1 and tlr3.2) and characterized. Constitutive gene expression of both tlr3.1 and tlr3.2 was detected by real-time PCR in cDNA of all analysed carp organs. Strikingly, 25 days after β-glucan feeding, very high levels of tlr3.1 gene expression were observed in all analysed organs, with the exception of the liver. Our data suggest that β-glucan-mediated protection against viral diseases could be due to an increased Tlr3-mediated recognition of ligands, resulting in an increased antiviral activity of Mx.  相似文献   
139.
Dandy–Walker malformation (DWM) is a rare intracranial congenital abnormality that affects the cerebellum and some of its components; particularly cerebellar vermis, fourth ventricle and is characterized by an enlarged posterior fossa. Although there is an extensive list of signs attributed to DWM, final diagnosis is solely dependent on imaging techniques as there are no signs that are characteristic of DWM. This article reports a case with DWM who was diagnosed by magnetic resonance imaging.  相似文献   
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