Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.727
Filtrar
1.
Methods Mol Biol ; 2074: 67-80, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31583631

RESUMO

Identifying residue-residue contacts in protein-protein interactions or complex is crucial for understanding protein and cell functions. DCA (direct-coupling analysis) methods shed some light on this, but they need many sequence homologs to yield accurate prediction. Inspired by the success of our deep-learning method for intraprotein contact prediction, we have developed RaptorX-ComplexContact, a web server for interprotein residue-residue contact prediction. Given a pair of interacting protein sequences, RaptorX-ComplexContact first searches for their sequence homologs and builds two paired multiple sequence alignments (MSA) based on genomic distance and phylogeny information, respectively. Then, RaptorX-ComplexContact uses two deep convolutional residual neural networks (ResNet) to predict interprotein contacts from sequential features and coevolution information of paired MSAs. RaptorX-ComplexContact shall be useful for protein docking, protein-protein interaction prediction, and protein interaction network construction.

2.
Int J Mol Sci ; 20(21)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683916

RESUMO

Although metabolic perturbations are sensitive indicators for low-dose toxic effects, the metabolic mechanisms affected by rac-metalaxyl and metalaxyl-M in mammals from a metabolic profiling perspective remain unclear. In this study, the metabolic perturbations and toxic effects of rac-metalaxyl and metalaxyl-M in mice were carefully investigated using integrative nuclear magnetic resonance (NMR) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) based metabolomics. Histopathology, NMR-based untargeted urine profile, multivariate pattern recognition, metabolite identification, pathway analysis, UPLC-MS/MS based targeted serum amino acids, and tryptophan pathway analysis were determined after rac-metalaxyl and metalaxyl-M exposure, individually. Histopathology indicated that metalaxyl-M induced greater hepatocellular inflammatory, necrosis, and vacuolation in mice than rac-metalaxyl at the same exposure dosage. The metabolic perturbations induced by rac-metalaxyl and metalaxyl-M were directly separated using partial least-squares discriminant analysis (PLS-DA). Furthermore, metabolite identification and pathway analysis indicated that rac-metalaxyl mainly induced ten urine metabolite changes and four pathway fluctuations. However, metalaxyl-M induced 19 urine metabolite changes and six pathway fluctuations. Serum amino acids and tryptophan pathway metabolite changes induced by rac-metalaxyl and metalaxyl-M were also different even at the same exposure level. Such results may provide specific insight into the metabolic perturbations and toxic effects of rac-metalaxyl and metalaxyl-M, and contribute to providing available data for health risk assessments of rac-metalaxyl and metalaxyl-M at a metabolomics level.

3.
Psychol Med ; : 1-12, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31685046

RESUMO

BACKGROUND: The microbiota-gut-brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients. METHODS: We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD. RESULTS: The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890. CONCLUSIONS: The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.

5.
BMC Bioinformatics ; 20(1): 556, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703550

RESUMO

BACKGROUND: As whole-genome sequencing is becoming a routine technique, it is important to identify a cost-effective depth of sequencing for such studies. However, the relationship between sequencing depth and biological results from the aspects of whole-genome coverage, variant discovery power and the quality of variants is unclear, especially in pigs. We sequenced the genomes of three Yorkshire boars at an approximately 20X depth on the Illumina HiSeq X Ten platform and downloaded whole-genome sequencing data for three Duroc and three Landrace pigs with an approximately 20X depth for each individual. Then, we downsampled the deep genome data by extracting twelve different proportions of 0.05, 0.1, 0.15, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 and 0.9 paired reads from the original bam files to mimic the sequence data of the same individuals at sequencing depths of 1.09X, 2.18X, 3.26X, 4.35X, 6.53X, 8.70X, 10.88X, 13.05X, 15.22X, 17.40X, 19.57X and 21.75X to evaluate the influence of genome coverage, the variant discovery rate and genotyping accuracy as a function of sequencing depth. In addition, SNP chip data for Yorkshire pigs were used as a validation for the comparison of single-sample calling and multisample calling algorithms. RESULTS: Our results indicated that 10X is an ideal practical depth for achieving plateau coverage and discovering accurate variants, which achieved greater than 99% genome coverage. The number of false-positive variants was increased dramatically at a depth of less than 4X, which covered 95% of the whole genome. In addition, the comparison of multi- and single-sample calling showed that multisample calling was more sensitive than single-sample calling, especially at lower depths. The number of variants discovered under multisample calling was 13-fold and 2-fold higher than that under single-sample calling at 1X and 22X, respectively. A large difference was observed when the depth was less than 4.38X. However, more false-positive variants were detected under multisample calling. CONCLUSIONS: Our research will inform important study design decisions regarding whole-genome sequencing depth. Our results will be helpful for choosing the appropriate depth to achieve the same power for studies performed under limited budgets.

6.
J Neurosci ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676602

RESUMO

Transient receptor potential vanilloid subtype 1 (TRPV1) is a nonselective cationic channel activated by painful stimuli such as capsaicin and noxious heat, and enriched in sensory neurons of the pain pathway. During inflammation, chemical mediators activate protein kinases (such as PKC) that phosphorylate TRPV1 and thereby enhance its function, with consequent increases in nociceptor sensitization. However, the causal relationships between TRPV1 phosphorylation and pathological pain remain unexplored. To directly investigate the roles of one specific TRPV1 phosphorylation event in vivo, we genetically altered a major PKC phosphorylation site, mouse TRPV1 S801, to alanine. The TRPV1 expression pattern in sensory neurons of S801A knock-in (KI) mice was comparable to that in wildtype (WT) controls. However, sensitization of capsaicin-mediated currents following the activation of PKC was substantially impaired in sensory neurons from KI mice. Thermal hyperalgesia induced by PMA or burn injury in KI was identical to WT. Inflammatory thermal hyperalgesia was only marginally attenuated in KI mice. In contrast, PMA-evoked nocifensive responses and sensitization of capsaicin responses were significantly attenuated in the hindpaws of KI mice. Ongoing pain from inflamed masseter muscle was also reduced in KI mice, and was further inhibited by the TRPV1 antagonist AMG9810. These results suggest that PKC-mediated phosphorylation of TRPV1 S801 contributes to inflammation-mediated sensitization of TRPV1 to ligand, but not heat, in vivo Further, this suggests that interference with TRPV1 S801 phosphorylation might represent one potential way to attenuate inflammatory pain, yet spare basal sensitivity and produce fewer side effects than more general TRPV1 inhibition.SIGNIFICANCE STATEMENTTRPV1 has been considered a potential target for pain intervention. Global inhibitors of TRPV1 function, however, produce side effects which could compromise their clinical utility. By precisely removing a unique PKC phosphorylation site (TRPV1 S801) in mice through CRISPR/Cas9 editing, we provide in vivo evidence for a highly specific inhibition that leaves basal TRPV1 function intact, yet alleviates some forms of hyperalgesia. These findings support inhibition of TRPV1 S801 phosphorylation as a potential intervention for pain management.

7.
BMC Musculoskelet Disord ; 20(1): 520, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699056

RESUMO

BACKGROUND: Nutritional factors including vitamin D, magnesium, and fat are known to affect bone mineral accrual. This study aimed to evaluate associations between dietary nutrient intakes (both macronutrients and micronutrients) and bone mineral density (BMD) in children and adolescents. METHODS: Data for this cross-sectional, population-based study were derived from the National Health and Nutrition Examination Survey (NHANES). Participants aged from 8 to 19 years were included. The primary outcome was femoral neck BMD. RESULTS: Multivariate analyses revealed that for participants aged 8 to 11, daily sodium intake was significantly and positively associated with femoral neck BMD (B = 0.9 ×  10- 5, p = 0.031); in particular, subgroup analyses by sex found that in male participants aged 8-11, daily total cholesterol intake (B = 5.3 × 10- 5, p = 0.030) and calcium intake (B = - 2.0 × 10- 5, p < 0.05) were significantly associated with femoral neck BMD in a positive and negative manner, respectively, but neither were observed in female participants of this age group. In contrast, daily intakes of vitamin D and magnesium were significantly and positively associated with femoral neck BMD in female participants aged 8-11 (B = 246.8 × 10- 5 and 16.3 × 10- 5, p = 0.017 and 0.033, respectively). For participants aged 16 to 19, daily total fat intake was significantly and negatively associated with femoral neck BMD (B = - 58 × 10- 5, p = 0.048); further stratification by sex found that magnesium and sodium intakes were significantly and positively associated with femoral neck BMD only in females of this age group (B = 26.9 × 10- 5 and 2.1 × 10- 5, respectively; both p < 0.05). However, no significant associations between daily nutrient intakes and femoral neck BMD were identified in participants aged 12-15 before or after subgroup stratification. CONCLUSION: The study found that associations of specific nutrition-related variables with BMD of the femoral neck is dependent upon age and gender.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31701580

RESUMO

In this study, we investigated the effects of Saccharomyces cerevisiae (SC), Bacillus subtilis (BS) and Enterococcus faecalis (EF), singly and in combination, on the dry matter intake (DMI), milk production and composition, and faecal microflora of Saanen dairy goats. Fifty goats were randomly divided into five groups: (a) basal diet (control); (b) basal diet + SC; (c) basal diet + BS; (d) basal diet + EF; and (e) basal diet + mixed probiotics. Each treated animal received 5 g/d of probiotics for a total administration of 5 × 1,011 CFU/goat per day. The inclusion of B. subtilis and E. faecalis in the diet of lactating Saanen goats increased DMI (p < .05). Enhanced milk yield was observed with BS and EF. Milk fat percentage was significantly increased by feeding mixed probiotics compared with the control (p < .05); supplying SC, BS and mixed probiotics enhanced the protein percentage (p < .05). The milk lactose percentage in the SC and BS groups was higher than in the control (p < .05). The amount of milk total solids was higher after feeding EF or mixed probiotics than in the control group (p < .05). Non-fat solids showed no notable differences among groups (p > .05). There was no significant influence on gut bacterial abundance and diversity from adding these three probiotics, singly or in combination. Bacteroidales, Escherichia-Shigella and Christensenellaceae abundances were decreased by supplying these probiotics but Succinivibrionaceae increased. In conclusion, there were positive influences of probiotic feed supplementation on intake, milk performance and intestinal microecology.

9.
J Clin Microbiol ; 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578261

RESUMO

Vaccination with inactivated vaccines is still the main measure to control foot-and-mouth disease (FMD) in endemic areas, and the level of neutralizing antibody in vaccinated animals is directly related to their protection against virus challenge. Currently, neutralizing antibody is mainly detected using virus neutralization test (VNT) based on cell culture, which is laborious, time-consuming and requiring restrictive biocontainment facilities. In this study, two broadly neutralizing antibodies (bnAbs) E46 and F128 were successfully produced using single B cell isolation techniques from peripheral blood mononuclear cells (PBMCs) of bovine sequentially immunized with three topotypes of foot-and-mouth disease virus (FMDV) serotype O. Based on these bnAbs, a blocking ELISA for detecting neutralizing antibodies (NA-ELISA) against FMDV serotype O was developed. The specificity and sensitivity of the test were estimated as 99.21% and 100%, respectively. A significant correlation (P<0.01) was observed between the NA-ELISA titers and the VNT titers for all sera from vaccinated animals and for all tested strains, suggesting that NA-ELISA could detect neutralizing antibodies against FMDV serotype O strains of wide antigenic and molecular diversity, and could be used for the evaluation of protective immunity.

10.
Bioinformatics ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31593235

RESUMO

MOTIVATION: Genome diagnostics have gradually become a prevailing routine for human healthcare. With the advances in understanding the causal genes for many human diseases, targeted sequencing provides a rapid, cost-efficient and focused option for clinical applications, such as SNP detection and haplotype classification, in a specific genomic region. Although nanopore sequencing offers a perfect tool for targeted sequencing because of its mobility, PCR-freeness, and long read properties, it poses a challenging computational problem of how to efficiently and accurately search and map genomic subsequences of interest in a pool of nanopore reads (or raw signals). Due to its relatively low sequencing accuracy, there is no reliable solution to this problem, especially at low sequencing coverage. RESULTS: Here, we propose a brand new signal-based subsequence inquiry pipeline as well as two novel algorithms to tackle this problem. The proposed algorithms follow the principle of subsequence dynamic time warping and directly operate on the electrical current signals, without loss of information in base-calling. Therefore, the proposed algorithms can serve as a tool for sequence inquiry in targeted sequencing. Two novel criteria are offered for the consequent signal quality analysis and data classification. Comprehensive experiments on real-world nanopore datasets show the efficiency and effectiveness of the proposed algorithms. We further demonstrate the potential applications of the proposed algorithms in two typical tasks in nanopore-based targeted sequencing: SNP detection under low sequencing coverage, and haplotype classification under low sequencing accuracy. AVAILABILITY: The project is accessible at https://github.com/icthrm/cwSDTWnano.git, and the presented bench data is available upon request.

12.
Phys Chem Chem Phys ; 21(41): 22819-22830, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31608353

RESUMO

We performed a density functional theory (DFT) study on X-ray photoelectron (XPS) and absorption (XAS) spectra of graphitic carbon nitride (g-C3N4) nanosheets at the N and C K-edges. A combined cluster-periodic approach was employed to calculate XPS spectra, in which the core ionic potential (IP) of the solid 2D material was computed by subtracting the work function (obtained with periodic conditions) from the gas phase IP (obtained with large cluster models). With amino-terminated supermolecules of different sizes, we obtained convergent spectra and provide new assignments for 5 nitrogen [1 sp2; 4 sp3 (bridging, tertiary, and primary/secondary amino nitrogens)] and 4 carbon (all bonded with three nitrogens) local structures. A good agreement with experiments was obtained, with the N1s (C1s) main peak position differing by 0.1-0.2 eV (0.5-0.8 eV). Our simulations show that N1s XPS of pure g-C3N4 contains only two major features at 398.6 and 401.2 eV, contributed from sp2-N and sp3-N, respectively. The chemical shifts of all sp3-N are so close (deviating by 0.3-0.6 eV) that terminal amino groups -NHx (x = 1, 2) will only be distinguished in high-resolution measurements. In C1s XPS, all carbons show similar (deviation < 0.2 eV) IPs, as determined by the same nearest neighbors. We further excluded the effect of shake-up satellites that may change our XPS interpretations by equivalent core hole time-dependent DFT (ECH-TDDFT) simulations. The effect of vibronic coupling is small (redistribution is only 0.1-0.3 eV to the higher-energy region) in the N1s edge as estimated from the asymmetric main peak shape, and negligible in the C1s edge. Quicker size convergence was found in XAS than XPS. In N1s XAS, we identified a weak π* spectral feature at 400-401 eV for both -NHx and tertiary nitrogens. Our study provides a clear theoretical reference for X-ray spectral fingerprints of different local structures, which is useful for analysis of g-C3N4 based materials with various designed or unavoidable structural modifications. We also highlight our combined cluster-periodic approach in calculating the K-edge XPS spectra of general 2D materials which predicts accurate absolute values.

13.
Cell Death Dis ; 10(11): 799, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641102

RESUMO

Following publication of this article [1], it was realized that an error was made in typesetting which resulted in a change in the ordering of the last two authors. The correct ordering of the authors for the paper is as follows:Mao Zhang, Shihai Liu, Mei-Sze Chua, Haoran Li, Dingan Luo, Sheng Wang, Shun Zhang, Chuandong Sun (*) & Bing Han (*)[(*) indicates corresponding author]An amendment to this paper has been published and can be accessed via a link at the top of the paper.

14.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(10): 992-997, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31642433

RESUMO

OBJECTIVE: To study the association of Nod-like receptor protein 3 (NLRP3) inflammasome with inflammatory response in the acute stage and coronary artery lesion (CAL) in children with Kawasaki disease (KD). METHODS: A total of 42 children with KD who were hospitalized from January to October 2017 were enrolled as the KD group, among whom 9 had CAL (CAL group) and 33 had no CAL (NCAL group). Fifteen age- and gender-matched children with pneumonia and pyrexia were enrolled as the pneumonia-pyrexia group. Fifteen healthy children were enrolled as the healthy control group. Real-time PCR was used to measure the mRNA expression of NLRP3 inflammasome (NLRP3, ASC and caspase-1) in peripheral blood mononuclear cells. The Spearman rank correlation test was used to investigate the correlation of NLRP3 mRNA expression with serum levels of C-reactive protein, erythrocyte sedimentation rate, interleukin-6, interleukin-1ß, procalcitonin, albumin and prealbumin. RESULTS: The KD group had significantly higher mRNA expression of NLRP3, ASC and caspase-1 in the acute stage than the pneumonia-pyrexia and healthy control groups (P<0.05). The CAL group had significantly higher mRNA expression of NLRP3 than the NCAL group (P<0.05). NLRP3 mRNA expression was correlated with C-reactive protein, interleukin-6, interleukin-1ß, and prealbumin levels in children with KD in the acute stage (rs=0.449, 0.376, 0.427, and -0.416 respectively; P<0.05). CONCLUSIONS: NLRP3 inflammasome may participate in inflammatory response in the acute stage and the development of CAL in children with KD.

15.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(10): 1049-1054, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31642443

RESUMO

OBJECTIVE: To study the changes and significance of apoptosis signal-regulating kinase 1 (ASK1) in left ventricular remodeling in FVB/N mice. METHODS: A total of 54 FVB/N mice were randomly divided into 4 groups: 0 d group with 8 mice, 7 d group with 10 mice, 14 d group with 16 mice, and 21 d group with 20 mice. A model of cardiac remodeling was established by intraperitoneal injection of isoproterenol (ISO) at a daily dose of 30 mg/kg, and the 7 d, 14 d, and 21 d groups were injected for 7, 14, and 21 consecutive days respectively. The 0 d group was given intraperitoneal injection of an equal volume of normal saline. Echocardiography was used to measure left ventricular posterior wall thickness at end diastole (dLVPW) and the ratio of heart weight to tibia length (HW/TL) was measured. Hematoxylin-eosin staining was used to measure left ventricular myocardial fiber diameter. Picric-Sirius red staining was used to measure myocardial collagen deposition area in the left ventricle. Quantitative real-time PCR was used to measure the mRNA expression of ASK1, type I collagen (collagen I), and B-type natriuretic peptide (BNP). The mortality rate was observed for each group. RESULTS: There were gradual increases in HW/TL, myocardial fiber diameter, and dLVPW after 0, 7, and 14 days of ISO injection (P<0.05). There were no significant changes in HW/TL ratio and dLVPW from days 14 to 21 of ISO injection (P>0.05), while there was a significant reduction in myocardial fiber diameter (P<0.05), which was similar to the value on day 7 (P>0.05). There were significant increases in myocardial collagen deposition area and the mRNA expression of collagen I, ASK1, and BNP after 0, 7, 14, and 21 days of ISO injection, which reached the peaks on day 21 (P<0.01). The mRNA expression of ASK1 was positively correlated with myocardial collagen deposition area and the mRNA expression of collagen I and BNP and had a weak correlation with HW/TL, myocardial fiber diameter, and dLVPW. There was a significant increase in the mortality rate of the mice over the time of ISO injection. CONCLUSIONS: The expression of ASK1 in the myocardium is closely associated with left ventricular remodeling. The increase of ASK1 expression may lead to the aggravation of left ventricular remodeling, and the mechanism of which needs further study.

16.
Scand J Clin Lab Invest ; : 1-12, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31663373

RESUMO

Osteosarcoma is a malignant bone tumor with extremely high invasion, metastasis and mortality. The prognosis of patients with osteosarcoma remains poor. The ErbB receptor family was found to be overexpressed in human cancers and associated with poor prognosis. However, the role of ErbB receptor family in osteosarcoma has not been fully understood. The present study aimed to investigate the clinicopathological and prognostic significances of ErbB receptors in primary osteosarcoma. Western blot (WB), reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and fluorescence in situ hybridization (FISH) were used to detect the protein and gene expression of ErbB receptors in 60 primary osteosarcoma specimens and 30 non-neoplastic bone tissues. WB and RT-qPCR analyses showed that the protein and mRNA expression levels of EGFR, ErbB3 and ErbB4 in osteosarcoma specimens were significantly higher than those in non-neoplastic bone tissues. Seventeen (28.33%), 15 (25.00%) and 15 (25.00%) osteosarcoma specimens presented with amplification of EGFR, ErbB3 and ErbB4 gene, respectively, which were significantly higher compared with non-neoplastic bone tissues. The amplification of ErbB3 and ErbB4 in osteosarcoma was associated with advanced surgical stage. The amplification of EGFR, ErbB3, ErbB4 and the co-amplification of EGFR-ErbB3, EGFR-ErbB4, ErbB3-ErbB4 was linked with poor response to chemotherapy and distant metastasis. The amplification of EGFR, ErbB3 and ErbB4, as well as their co-amplification demonstrated independent prognostic values for reduced survival time of osteosarcoma patients and may serve as potential therapeutic targets for osteosarcoma patients in the future.

17.
Nat Plants ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31636399

RESUMO

Soil-borne fungal pathogens that cause crop disease are major threats to agriculture worldwide. Here, we identified a secretory polysaccharide deacetylase (PDA1) from the soil-borne fungus Verticillium dahliae, the most notorious plant pathogen of the Verticillium genus, that facilitates virulence through direct deacetylation of chitin oligomers whose N-acetyl group contributes to host lysine motif (LysM)-containing receptor perception for ligand-triggered immunity. Polysaccharide deacetylases are widely present in fungi, bacteria, insects and marine invertebrates and have been reported to possess diverse functions in developmental processes rather than virulence. A phylogenetics analysis of more than 5,000 fungal proteins with conserved polysaccharide deacetylase domains showed that the V. dahliae PDA1-containing subtree includes a large number of proteins from the Verticillium genus as well as the Fusarium genus, another group of characterized soil-borne fungal pathogens, suggesting that soil-borne fungal pathogens have adopted chitin deacetylation as a major virulence strategy. We showed that a Fusarium PDA1 is required for virulence in cotton plants. This study reveals a substantial virulence function role of polysaccharide deacetylases in pathogenic fungi and demonstrates a subtle mechanism whereby deacetylation of chitin oligomers converts them to ligand-inactive chitosan, representing a common strategy of preventing chitin-triggered host immunity by soil-borne fungal pathogens.

18.
Drug Des Devel Ther ; 13: 3529-3538, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31631977

RESUMO

Objective: Chondrocyte apoptosis has also been strongly correlated with the severity of cartilage damage and matrix depletion in an osteoarthritis (OA) joint. Therefore, pharmacological inhibitors of apoptosis may provide a novel treatment option for patients with OA. Aucubin, a natural compound isolated from Eucommia ulmoides, has been proved to possess antioxidative and anti-apoptotic properties. However, anti-osteoarthritis effect of aucubin in animal model and anti-apoptotic response of aucubin in OA chondrocytes remain unclear. This study aimed to determine whether aucubin could slow progression of OA in a mouse model and inhibit the IL-1ß-induced chondrocyte apoptosis. Methods: OA severity and articular cartilage degradation were evaluated by Safranin-O staining, Hematoxylin-eosin (H&E) staining, and Osteoarthritis Research Society International (OARSI) standards. Chondrocyte viability was observed by Cell Counting Kit-8 (CCK8) and live/dead cells assay; the apoptotic rate of chondrocytes was evaluated by flow cytometry (FCM) with Annexin V-FITC/PI kit. Mediators of apoptosis were tested by Western blot of Bax, caspase-3, caspase-9, and Bcl-2 expression. The intracellular levels of Reactive oxygen species (ROS) were assessed by the probe of 2,7-Dichlorofluorescin diacetate (DCFH-DA). Results: The articular cartilage in the limb with destabilization of the medial meniscus (DMM) exhibited early OA-like manifestations characterized by proteoglycan loss, cartilage fibrillation, and erosion, with lower OARSI score. Oral administration of aucubin remarkably attenuated the loss of proteoglycan and the articular cartilage erosion and decreased the OARSI scores underwent DMM surgery. Aucubin treatment significantly reverses IL-1ß-induced cytotoxicity and attenuated the IL-1ß-induced chondrocyte apoptosis. In addition, aucubin can significantly inhibit mediators of apoptosis in rat primary chondrocytes. Furthermore, aucubin remarkably attenuated the IL-1ß-induced intracellular ROS production. Conclusion: Our findings suggest that aucubin has a protective effect on articular cartilage and slowing progression of OA in a mouse model. This protective effect may result from inhibiting chondrocyte apoptosis and excessive ROS production.

19.
Inorg Chem ; 58(20): 13892-13901, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31565936

RESUMO

Four diplatinum(II) complexes with the formula [Pt(pypm)(µ-Fn)]2 (2, 3a-c) bearing both a pyridine-pyrimidinate chelate and formamidinate bridge, where (pypm)H and FnH stand for 5-(pyridin-2-yl)-2-(trifluoromethyl)pyrimidine and functional formamidines with various substituents of iPr (n = 1), Ph (n = 2), C6H4tBu (n = 3), and C6H4CF3 (n = 4), were synthesized en route from a mononuclear intermediate represented by [Pt(pypm)Cl(F1H)] (1). Single-crystal X-ray diffraction studies confirmed the structure of 1 and 3a comprised of an individual "Pt(pypm)" unit and two "Pt(pypm)" units with a Pt···Pt distance of 2.8845(2) Å, respectively. Therefore, in contrast to the structured emission of mononuclear 1 with the first vibronic peak wavelength at 475 nm, all other diplatinum complexes with shortened Pt···Pt separation exhibited greatly red shifted and structureless metal-metal to ligand charge transfer (MMLCT) emission that extended into the near-infrared region in solid states. Their photophysical characteristics were measured under three distinctive morphological states (i.e., crystals, sublimed powders, and vacuum-deposited thin films) by steady-state UV-vis spectroscopy, while retention of Pt···Pt interactions in deposited thin films of 2 and 3a-c was confirmed using Raman spectroscopy, demonstrating lowered Pt···Pt stretching at 80-200 cm-1. Most importantly, complexes 3a-c exhibited a gradual red shift with the trends crystals < sublimed powders < vacuum-deposited thin films, a result of increased intermolecular π-π stacking interactions and Pt···Pt interactions, while crystalline samples exhibited the highest luminescence among all three morphological states due to the fewest defects in comparison to other morphologies. Finally, 3b was selected as a nondoped emitter for the fabrication of NIR-emitting OLEDs, giving an electroluminescence peak at 767 nm and a maximum external quantum efficiency of 0.14% with negligible roll-off.

20.
J Dairy Sci ; 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31629528

RESUMO

The objective of this study was to develop a novel immobilized system using kefir lactic acid bacteria and sugar cane pieces for the production of fermented milk. Lactobacillus kefiranofaciens HL1, Lactobacillus kefiri HL2, Leuconostoc mesenteroides HL3, and Lactococcus lactis HL4 were isolated from Taiwanese kefir grains and immobilized on pieces of sugar cane using adsorption. Scanning electron micrographs of the cell-immobilized sugar cane pieces (CISCP) showed that the microorganisms were embedded within the porous structures of the sugar cane pieces. During 28 cycles of repeated batch fermentation, viable cells on both sugar cane pieces and fermented products were maintained at 10 log cfu/g (cfu/mL). Random amplified polymorphic DNA PCR analysis revealed that Leu. mesenteroides HL3 (29-43%) and Lc. lactis HL4 (31-49%) were predominant on the CISCP, and the fermented samples had 79% Lc. lactis HL4. When tracking fermentation parameters, the data on the microbial, chemical, and physical properties of the fermented milk suggested that the CISCP had stable fermentative ability over the course of successive fermentations. We found an enhancement of the acid-producing ability of CISCP as the number of fermentations increased, with a significant growth in titratable acidity from 0.65 to 0.81% by the end.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA