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141.
Length weight relationships (LWRs) were estimated for three gobiid species, Bathygobius meggitti(Hora & Mukerji, 1936), Acentrogobius dayi Koumans, 1941 and Cryptocentroides arabicus(Gmelin, 1789) (Perciformes: Gobiidae) collected from 13 localities of the Iranian intertidal coast of the Persian Gulf and Makran Sea in seven times from November 2015 to September 2017 using a hand net with mesh size 1.30 mm. The b values showed significant differences between males and females of all species except the C. arabicus. Bailey's t test revealed that b value significantly deviated from the expected cube value of 3 in three species.  相似文献   
142.
In this study, length‐length relationships (LLRs) and weight‐length relationships (WLRs) were established for a Carangidae species: Uraspis helvola and tow Flatfishes: Pseudorhombus elevatus and Psettodes erumei that are substantial marine fish species to commercial fisheries in Persian Gulf that are indigenous marine fish species in the region. Samples were collected by non‐selective fish bottom trawler with stretch mesh size of 4 centimeters at the cod‐end area, which helped us to obtain such a broad range size that included small, medium and large size classes during June to August 2017. Hitherto, the length‐weight model presented in this study for Pseudorhombus elevatus and Uraspis helvola were not documented on Fishbase. Additionally, new records of maximum length are presented as 64.5 and 30 centimeters for P. erumei and P. elevatus respectively. A comprehensive size distribution and highly significant fitted model (r2>0.95) in this research provides useful insight for future studies on fish biology, fisheries assessment and ecological modeling.  相似文献   
143.
Triterpenoid saponins are a diverse group of bioactive compounds, which are used for possessing of many biomedical and pharmaceutical products. Generally, squalene synthase (SQS) is defined as an emerging and essential branch point enzyme far from the major pathway of isoprenoids biosynthetic and a latent adjusting point, which manages carbon flux into triterpenes biosynthesis and sterols. The present study deals with the detailed characterization of SQS by bioinformatics approaches to evaluate physicochemical properties, structural characteristics including secondary and 3D structure prediction and functional analysis from eight plants related to Fabaceae family and Arabidopsis thaliana. Bioinformatics analysis revealed that SQS proteins have two transmembrane regions in the C-terminal. The predicted motifs were used to design universal degenerate primers for PCR analysis and other molecular applications. Phylogenetic analysis showed conserved regions at different stretches with maximum homology in amino acid residues within all SQSs. The secondary structure prediction results showed that the amino acid sequence of all squalene synthases had α helix and random coil as the main components. The reliability of the received model was confirmed using the ProSA and RAMPAGE programs. Determining of active site by CASTp proposes the possibility of using this protein as probable medication target. The findings of the present study may be useful for further assessments on characterization and cloning of squalene synthase.  相似文献   
144.
Catalytic combustion of hydrocarbons is an important technology to produce energy. Compared to conventional flame combustion, the catalyst enables this process to operate at lower temperatures; hence, reducing the energy required for efficient combustion. The reaction and activation energies of direct combustion of hydrocarbons (CH?→?C?+?H) on a series of metal surfaces were investigated using density functional theory (DFT). The data obtained for the Ag, Au, Al, Cu, Rh, Pt, and Pd surfaces were used to investigate the validity of the Brønsted-Evans-Polanyi (BEP) and transition state scaling (TSS) relations for this reaction on these surfaces. These relations were found to be valid (R2?=?0.94 for the BEP correlation and R2?=?1.0 for the TSS correlation) and were therefore used to estimate the energetics of the combustion reaction on Ni, Co, and Fe surfaces. It was found that the estimated transition state and activation energies (ETS?=??69.70 eV and Ea?=?1.20 eV for Ni, ETS?=??87.93 eV and Ea?=?1.08 eV for Co and ETS?=??92.45 eV and Ea?=?0.83 eV for Fe) are in agreement with those obtained by DFT calculations (ETS?=??69.98 eV and Ea?=?1.23 eV for Ni, ETS?=??87.88 eV and Ea?=?1.08 eV for Co and ETS?=??92.57 eV and Ea?=?0.79 eV for Fe). Therefore, these relations can be used to predict energetics of this reaction on these surfaces without doing the time consuming transition state calculations. Also, the calculations show that the activation barrier for CH dissociation decreases in the order Ag ? Au ? Al ? Cu ? Pt ? Pd ? Ni?>?Co?>?Rh?>?Fe.  相似文献   
145.

Background aims

Adipose tissue–derived mesenchymal stromal cells (AT-MSCs), widely known as multipotent progenitors, release several cytokines that support cell survival and repair. There are in vitro and in vivo studies reporting the regenerative role of AT-MSCs possibly mediated by their protective effects on functional islet cells as well as their capacity to differentiate into insulin-producing cells (IPCs).

Methods

On such a basis, our goal in the present study was to use three different models including direct and indirect co-cultures and islet-derived conditioned medium (CM) to differentiate AT-MSCs into IPCs and to illuminate the molecular mechanisms of the beneficial impact of AT-MSCs on pancreatic islet functionality. Furthermore, we combined in vitro co-culture of islets and AT-MSCs with in vivo assessment of islet graft function to assess whether co-transplantation of islets with AT-MSCs can reduce marginal mass required for successful islet transplantation and prolong graft function in a diabetic rat model.

Results

Our findings demonstrated that AT-MSCs are suitable for creating a microenvironment favorable for the repair and longevity of the pancreas β cells through the improvement of islet survival and maintenance of cell morphology and insulin secretion due to their potent properties in differentiation. Most importantly, hybrid transplantation of islets with AT-MSCs significantly promoted survival, engraftment and insulin-producing function of the graft and reduced the islet mass required for reversal of diabetes.

Conclusions

This strategy might be of therapeutic potential solving the problem of donor islet material loss that currently limits the application of allogeneic islet transplantation as a more widespread therapy for type 1 diabetes.  相似文献   
146.
Spexin (SPX) is a novel biomarker abundantly expressed in several animal and human tissues implicated in food intake and glucose control, respectively. As new roles for SPX are emerging, the present study explored for the first time, the associations of SPX to several cardiometabolic indices and inflammatory markers in pregnant women, a demographic not yet investigated with respect to SPX. A total of 117 Saudi women subdivided to those with gestational diabetes mellitus (GDM) (N?=?63) and those without (N?=?54) were included in this cross-sectional study. Anthropometry, glycemic, lipid, vitamin D, adipocytokines and inflammatory markers were measured consecutively at baseline and after the 2nd and 3rd trimesters. Age- and BMI adjusted comparisons revealed that levels of SPX were not significantly different in pregnant women with and without GDM. In all subjects, circulating levels of SPX showed modest associations with glucose (R?=?0.18; p?=?.08) and HOMA β (R?=??0.19; p?=?.09) as well as significant positive associations with total cholesterol (R?=?0.25; p?=?.02), LDL-cholesterol (R?=?0.25; p?=?.02), 25(OH)D (R?=?0.22; p?=?.04), albumin (R?=?0.30; p?<?.01) and IL1β (R?=?0.41; p?<?.01). Stepwise regression analysis also suggested that IL1β, leptin and albumin were the significant predictors of SPX. In summary, SPX levels modestly affect glucose and insulin sensitivity in pregnant women but is not associated with GDM and obesity. The significant association of SPX to ILβ warrants further investigation as to the role of SPX in immune modulation.  相似文献   
147.
Prangos ferulacea is one of the widely used, nutritional and popular fodders in livestock industry. This species is also considered as an important option in rangeland restoration and management. In this study, the comparative phytotoxic activity of aqueous and hydroalcoholic extracts obtained from different organs (flower, shoot and leaf) of P. ferulacea on proline content, seed germination and seedling growth of Trifolium resupinatum has been investigated. According to the results, the hydroalcoholic extract of P. ferulaceae flower possesses the highest total phenolic and flavonoid content and the uppermost phytotoxic effect on T. resupinatum. The extracts significantly decreased seed germination and seedling growth of T. resupinatum and increased the proline content. Our findings indicate that hydroalcoholic extract induced a stronger oxidative stress in T. resupinatum. Finally, based on the results, aqueous allelochemicals that originated from P. ferulacea played a significant role in the successful propagation and development of T. resupinatum in rehabilitated pastures. According to our results, the phytotoxicity effect of the hydroalcoholic extract was significantly higher than that of the aqueous extract. Since in nature, the allelopathic interaction between plants is closer to the aqueous method, primary evaluations of rangeland restoration using this method is suggested.  相似文献   
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High incidence of articular cartilage defects resulting from age-related degeneration or trauma injuries is a major problem worldwide. Limited self-regeneration ability of cartilage often leads to inappropriate biochemistry and structure of healed tissue. Considering Impairments of traditional treatments, cell-based therapies are promising. The rapid ex vivo expansion and chondrogenic differentiation capability make dental pulp stem cells (DPSCs) a favorable cell type for therapeutic application, however strategies in order to efficient cartilage tissue-like production are imperative. In the present study the potential role of hypoxia mimicking agent, cobalt chloride (CoCl2), on chondrogenic differentiation of human DPSCs was surveyed. Cell viability assay used to obtain the optimum dose and exposure time of CoCl2. DPSCs were differentiated in pellet culture system after CoCl2 pretreatment. Chondrogenic differentiation efficiency was evaluated by histological and immunohistological analyses. The results showed that CoCl2 led to increased pellet size, integrity and matrix deposition with organizations more resembled typical cartilage lacuna structure. Furthermore, CoCl2 could improve differentiation by elevated chondrogenic markers, glycosaminoglycans (GAGs) and collagen II expression. CoCl2 pretreatment mitigated hypertrophy, as well, which was reflected in decreased collagen X expression. Alkaline phosphatase (ALP) specific activity did not change significantly by CoCl2 preconditioning. Based on current study hypoxia mimicking agent, CoCl2, could be suggested to promote DPSCs chondrogenic differentiation.  相似文献   
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