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1.
Phytochemistry ; 216: 113873, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37769958

RESUMEN

Endophytes coevolve with plant hosts and thus are more probable to acquire the character (in favor) of producing undescribed bioactive metabolites. Consequently, the topic has been intensely investigated for over two decades, but endophytic metabolites with neuroprotective effect remain scarce. The study presents the discovery of eight undescribed (named solanapyrones U-Z and prosolanapyrones A and B) and six known pyrones (solanapyrones A-C and E-G) from the culture of Nigrospora oryzae, an endophytic fungus associated with Taxus chinensis var. mairei. The structures and absolute configurations of undescribed pyrones were elucidated by extensive spectroscopic analysis, modified Mosher's method, and induced circular dichroism (ICD) spectrum. Solanapyrones A and B and an undescribed pyrone (solanapyrone U) were demonstrated to be more neuroprotective than clenbuterol in inducing bone marrow mesenchymal stem cells (bMSCs) to secret nerve growth factor (NGF). The work updates the pyrone chemodiversity in nature and extends the biofunction repertoire of solanapyrone-related polyketides.


Asunto(s)
Ascomicetos , Taxus , Taxus/microbiología , Pironas/química , Dicroismo Circular
2.
Acta Trop ; 245: 106977, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37399980

RESUMEN

Fascioliasis, a global zoonotic parasitic disease, is mainly caused by Fasciola hepatica (F. hepatica) parasitizing in the livers of hosts, mainly humans and herbivores. Glutathione S-transferase (GST) is one of the important excretory- secretory products (ESPs) from F. hepatica, however, the regulatory roles of its Omega subtype in the immunomodulatory effects remain unknown. Here, we expressed F. hepatica recombinant GSTO1 protein (rGSTO1) in Pichia pastoris and analyzed its antioxidant properties. Then, the interaction between F. hepatica rGSTO1 and RAW264.7 macrophages and its effects on inflammatory responses and cell apoptosis were further explored. The results revealed that GSTO1 of F. hepatica owned the potent ability to resist oxidative stress. F. hepatica rGSTO1 could interact with RAW264.7 macrophages and inhibit its cell viability, furthermore, it may suppress the production of pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α, but promote the expression of anti-inflammatory cytokine IL-10. In addition, F. hepatica rGSTO1 may down-regulate the ratio of Bcl-2/Bax, and increase the expression of pro-apoptotic protein caspase-3, thereby eliciting the apoptosis of macrophages. Notably, F. hepatica rGSTO1 inhibited the activation of nuclear factor-κB (NF-κB) and mitogen­activated protein kinases (MAPKs p38, ERK and JNK) pathways in LPS-activated RAW264.7 cells, exerting potent modulatory effects on macrophages. These findings suggested that F. hepatica GSTO1 can modulate the host immune response, which provided new insights into the immune evasion mechanism of F. hepatica infection in host.


Asunto(s)
Fasciola hepatica , Fascioliasis , Glutatión Transferasa , Animales , Humanos , Ratones , Apoptosis , Citocinas/metabolismo , Fasciola hepatica/fisiología , Fascioliasis/metabolismo , Fascioliasis/parasitología , Fascioliasis/patología , Glutatión Transferasa/metabolismo , Macrófagos
3.
Front Public Health ; 11: 1170782, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37333524

RESUMEN

Objective: As China's population aging process accelerates, the expenditure of China's basic medical insurance fund for employees may increase significantly, which may threaten the sustainability of China's basic medical insurance fund for employees. This paper aims to forecast the future development of China's basic medical insurance fund for employees in the context of the increasingly severe aging of the population. Methods: This paper taking an empirical study from Shanghai as an example, constructs an actuarial model to analyze the impact of changes in the growth rate of per capita medical expenses due to non-demographic factors and in the population structure on the sustainability of the basic medical insurance fund for employees. Results: Shanghai basic medical insurance fund for employees can achieve the goal of sustainable operation in 2021-2035, with a cumulative balance of 402.150-817.751 billion yuan in 2035. The lower the growth rate of per capita medical expenses brought about by non-demographic factors, the better the sustainable operation of the fund. Conclusion: Shanghai basic medical insurance fund for employees can operate sustainably in the next 15 years, which can further reduce the contribution burden of enterprises, which lays the foundation for improving the basic medical insurance treatment for employees.


Asunto(s)
Administración Financiera , Seguro , Humanos , China/epidemiología , Dinámica Poblacional , Envejecimiento
4.
Front Public Health ; 11: 1111288, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37077185

RESUMEN

Introduction: Against the background of population aging and large-scale internal migration, this study uses an ordered logit with two-way fixed effects to examine the effect of children's internal migration on the subjective wellbeing of parents left behind. The study is based on the China Family Panel Studies database. Methods: Data were obtained from CFPS (China Family Panel Studies), and ordered logit with two-way fixed effects was used to test the total effect of children's internal migration on subjective wellbeing of parents left behind, and KHB test was used to separate intergenerational spiritual support and intergenerational financial support to examine the intergenerational support preferences of parents left behind. Results: The results show that children's internal migration has a significant negative effect on the subjective wellbeing of parents left behind, mainly through the reduction of intergenerational spiritual support. Furthermore, intergenerational financial support significantly mitigates this negative effect. There is heterogeneity in the direction of the total wellbeing effect across parents' preferences, as well as in the masking effect of financial support. However, the effect of financial support never fully offsets the effect of spiritual support. Discussion: To cope with the negative effects of children's internal migration on parents, positive measures should be taken to change parental preferences.


Asunto(s)
Envejecimiento , Padres , Humanos , Niño , Población Rural , China/epidemiología , Relaciones Padres-Hijo
5.
J Agric Food Chem ; 71(14): 5783-5795, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36977356

RESUMEN

4-Hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) is one of the most promising herbicide targets for the development of agricultural chemicals owing to its unique mechanism of action in plants. We previously reported on the co-crystal structure of Arabidopsis thaliana (At) HPPD complexed with methylbenquitrione (MBQ), an inhibitor of HPPD that we previously discovered. Based on this crystal structure, and in an attempt to discover even more effective HPPD-inhibiting herbicides, we designed a family of triketone-quinazoline-2,4-dione derivatives featuring a phenylalkyl group through increasing the interaction between the substituent at the R1 position and the amino acid residues at the active site entrance of AtHPPD. Among the derivatives, 6-(2-hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,5-dimethyl-3-(1-phenylethyl)quinazoline-2,4(1H,3H)-dione (23) was identified as a promising compound. The co-crystal structure of compound 23 with AtHPPD revealed that hydrophobic interactions with Phe392 and Met335, and effective blocking of the conformational deflection of Gln293, as compared with that of the lead compound MBQ, afforded a molecular basis for structural modification. 3-(1-(3-Fluorophenyl)ethyl)-6-(2-hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,5-dimethylquinazoline-2,4(1H,3H)-dione (31) was confirmed to be the best subnanomolar-range AtHPPD inhibitor (IC50 = 39 nM), making it approximately seven times more potent than MBQ. In addition, the greenhouse experiment showed favorable herbicidal potency for compound 23 with a broad spectrum and acceptable crop selectivity against cotton at the dosage of 30-120 g ai/ha. Thus, compound 23 possessed a promising prospect as a novel HPPD-inhibiting herbicide candidate for cotton fields.


Asunto(s)
4-Hidroxifenilpiruvato Dioxigenasa , Arabidopsis , Herbicidas , Herbicidas/química , Estructura Molecular , Relación Estructura-Actividad , 4-Hidroxifenilpiruvato Dioxigenasa/química , Arabidopsis/metabolismo , Gossypium/metabolismo , Quinazolinas/química
6.
Clin Nutr ; 41(12): 2706-2719, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36351362

RESUMEN

BACKGROUND & AIMS: The interplay among dietary intake, gut microbiota, gut metabolites and circulating metabolites in adolescents is barely known, not to mention sex-dependent pattern. We aimed to explore unique profiles of gut bacterial, gut metabolites and circulating metabolites from both genders of adolescents due to BMI and eating pattern. METHODS: Clinical indices, fecal gut microbiota, fecal and plasma metabolites, and diet intake information were collected in case-control sample matched for normal and obesity in girls (normal = 12, obesity = 12) and boys (normal = 20, obesity = 20), respectively. 16S rRNA gene sequencing and untargeted metabolomics was performed to analysis the signature of gut microbiota and metabolites. Unique profiles of girls associated with BMI and eating pattern was revealed by Spearman's correlations analysis, co-occurrence network analysis, Kruskal-Wallis test, and Wilcoxon rank-sum test. RESULTS: Gender difference was found between normal and obese adolescents in gut microbiota, fecal metabolites, and plasma metabolites. The Parabacteroides were only decreased in obese girls. And the characteristic of obese girls' and boys' cases in fecal and plasma was xanthine and glutamine, ornithine and LCA, respectively. Soy products intake was negatively associated with Parabacteroides. The predicted model has a higher accuracy based on the combined markers in obesity boys (AUC = 0.97) and girls (AUC = 0.97), respectively. CONCLUSIONS: Reduced abundance of Phascolarctobacterium and Parabacteroides, as well as the increased fecal xanthine and ornithine, may provide a novel biomarker signature in obesity girls and boys. Soy products intake was positively and negatively associated with Romboutsia and Parabacteroides abundance, respectively. And the combined markers facilitate the accuracy of predicting obesity in girls and boys in advance.


Asunto(s)
Microbioma Gastrointestinal , Obesidad Infantil , Adolescente , Humanos , Femenino , Masculino , Microbioma Gastrointestinal/genética , ARN Ribosómico 16S , Heces/microbiología , Metaboloma , Ingestión de Alimentos , Biomarcadores , Ornitina , Xantinas
7.
Carbohydr Polym ; 298: 120023, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36241256

RESUMEN

Polysaccharides are important constituents in Dolichos lablab hull. Herein, pectin-glucuronoxylan complex from D. lablab hull designated as DLHP-3 (D. lablab hull polysaccharide,) was prepared by ion exchange and gel permeation chromatography, and further characterized by acid degradation and enzymatic hydrolysis, methylation combined with GC-MS, NMR and MALDI-TOF-MS analysis. Both of pectin and glucuronoxylan regions were found in DLHP-3. The glucuronoxylan region consisted of a →4)-ß-Xylp-(1→ backbone with branches of α-GlcpA-(1→ substituted at O-2 site, and the ratio of xylose to glucuronic acid was about 5:1. Acetyl groups were mainly attached to O-3 site of →2,4)-ß-Xylp-(1→ residues. The main chain of pectin region could be represented by →4)-α-GalpA-(1→4)-α-GalpA-(1→ and →2)-α-Rhap-(1→4)-α-GalpA-(1→ with partial methyl-esterification. The side chains were deduced to embrace arabinan and arabinogalactan linked to rhamnogalacturonan-I region. Pectin was probably covalently bound to glucuronoxylan. Our findings uncovered the molecular structure of pectin-glucuronoxylan complex from D. lablab hull.


Asunto(s)
Dolichos , Dolichos/metabolismo , Ácido Glucurónico , Pectinas/química , Polisacáridos/química , Ramnogalacturonanos , Xilanos , Xilosa
8.
Front Pharmacol ; 13: 950368, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36081932

RESUMEN

Background: Traumatic spinal cord injury (t-SCI) is a severe injury that has a devastating impact on neurological function. Blood spinal cord barrier (BSCB) destruction following SCI aggravates the primary injury, resulting in a secondary injury. A series of experimental treatments have been proven to alleviate BSCB destruction after t-SCI. Methods: From a screen of 1,189 papers, which were retrieved from Pubmed, Embase, and Web of science, we identified 28 papers which adhered to strict inclusion and exclusion criteria. Evans blue (EB) leakage on the first day post-SCI was selected as the primary result. Secondary outcomes included the expression of tight junction (TJ) proteins and adhesion junction (AJ) proteins in protein immunoblotting. In addition, we measured functional recovery using the Basso, Beattie, Besnahan (BBB) score and we analyzed the relevant mechanisms to explore the similarities between different studies. Result: The forest plot of Evans blue leakage (EB leakage) reduction rate: the pooled effect size of the 28 studies was 0.54, 95% CI: 0.47-0.61, p < 0.01. This indicates that measures to mitigate BSCB damage significantly improved in reducing overall EB leakage. In addition TJ proteins (Occludin, Claudin-5, and ZO-1), AJ proteins (P120 and ß-catenin) were significantly upregulated after treatment in all publications. Moreover, BBB scores were significantly improved. Comprehensive studies have shown that in t-SCI, inhibition of matrix metalloproteinases (MMPs) is the most commonly used mechanism to mitigate BSCB damage, followed by endoplasmic reticulum (ER) stress and the Akt pathway. In addition, we found that bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exos), which inhibit the TIMP2/MMP signaling pathway, may be the most effective way to alleviate BSCB injury. Conclusion: This study systematically analyzes the experimental treatments and their mechanisms for reducing BSCB injury in the early stage of t-SCI. BMSC-Exos, which inhibit MMP expression, are currently the most effective therapeutic modality for alleviating BSCB damage. In addition, the regulation of MMPs in particular as well as the Akt pathway and the ER stress pathway play important roles in alleviating BSCB injury. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022324794.

9.
J Vet Res ; 66(2): 199-207, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35892103

RESUMEN

Introduction: Fasciola hepatica is a trematode infecting ruminants worldwide and occasionally affecting other animal species, including humans. It causes significant economic losses. Geographic distribution and patterns of infection must be considered before control and management measures are developed for this parasite. DNA molecular markers are useful for the identification of flukes and elucidation of their genetic evolution. Therefore, the population structure of F. hepatica was studied using this method in sheep in Xinjiang, China. Material and Methods: The molecular characteristics, genetic relationships within the population and dispersal patterns of F. hepatica isolates were analysed based on the cox1 and nad1 genes. The population structure of F. hepatica from three regions of Xinjiang was explored and a neutrality test was conducted. Results: The cox1 and nad1 genes have 21 and 42 variable sites, respectively, which can be classified into 34 and 33 haplotypes. Median-joining network and phylogenetic tree analyses showed that there was no significant variation in F. hepatica isolates between the three geographical regions. Analysis of variance revealed that the genetic variation of F. hepatica was mainly present within the populations. The neutrality test indicated that the populations were relatively stable but the Hami population may have undergone short-term expansion. Conclusion: This study revealed for the first time the molecular characteristics, genetic diversity and dispersal patterns of F. hepatica isolates from sheep in Xinjiang, thus providing new insights into the genetic variation and haplotype diversity of F. hepatica from indigenous sheep.

10.
J Hazard Mater ; 427: 128169, 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-34979386

RESUMEN

Traditionally, lead (Pb) in rice grains has been thought to be mostly derived from soil, and the contribution of aerosol Pb remains so far unknown. Based on a meta-analysis, we surprisingly found rice Pb content decreased proportionally with urban atmospheric Pb concentrations in major rice-growing provinces in China during 2001-2015, suggestive of the strong influence of long-range Pb transport on agricultural environment. With the combination of field survey, field experiment, as well as a predictive model, we confirmed high contribution of atmospheric exposure to rice grain Pb in China. We for the first time developed a predictive mathematical model which revealed that aerosol Pb accumulation ratios of rice grains were related to both grain weight and accumulation types. We successfully predicted the national-scale rice Pb in China on the basis of the public data of urban PM2.5 from 19 rice-growing provinces and proposed a seasonal atmospheric Pb limit of 0.20 µg m-3 based on the safe threshold level of Pb in rice, which was much lower than the current limit of 1 µg m-3 set in China.


Asunto(s)
Oryza , Contaminantes del Suelo , China , Grano Comestible/química , Plomo , Suelo , Contaminantes del Suelo/análisis
11.
Food Chem ; 368: 130772, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34399182

RESUMEN

Macrolepiota albuminosa (Berk.) Pegler is abundant in active polysaccharides, but little is known about their structures and solution properties. In this study, water-extracted polysaccharides from M. albuminosa (MAWP) were purified into three fractions with structural heterogeneity, which was attributed to the diversity in molecular weight, monosaccharide composition and linkage patterns, further affecting their solution properties. Methylation and NMR analysis revealed MAWP-60p and MAWP-70 were a 3-O-methylated glucomannogalactan and a previously unreported glucomannogalactan, whereas MAWP-80 was elucidated as a branched galactoglucan. Besides, three fractions exhibited random coil conformation in aqueous solution, while MAWP-60p had the highest viscosity due to its highest molecular weight, mean square radius of gyration (Rg) and O-methyl group attached to the backbone. The molecular weight, monosaccharide composition and glycosidic linkages might be the major contributors to the flexibility, molecular size and stereochemistry of mushroom polysaccharide chains.


Asunto(s)
Agaricales , Polisacáridos , Carbohidratos de la Dieta , Peso Molecular , Monosacáridos , Viscosidad
12.
Zookeys ; 1134: 52-73, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761111

RESUMEN

In the present paper, a new species of cynipid gall wasp, Andricuselodeoides Liu & Pang, is described from several provinces in southern China. The new species is closely related to the recently redescribed A.mairei (Kieffer, 1906). In addition to differences in adult and gall morphology, the new species is also readily separated by COI sequences, with a 6.2-8.9% genetic distance between populations of the new species and those of A.mairei. A contrasting difference in sex ratios was also observed between the two species, with A.elodeoides extremely female-biased (95.5-97.8% female) while A.mairei male-biased to more balanced (5.4-43.5% female). PCR screening for Wolbachia infection further revealed contrasting infection rates between populations of A.elodeoides and A.mairei: the Wolbachia infection rate was 0% in A.elodeoides and 100% in A.mairei. Cytoplasmic incompatibility induced by Wolbachia is proposed as a potential mechanism of speciation of the sympatric A.elodeoides and A.mairei.

13.
Biomedicines ; 9(12)2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34944561

RESUMEN

Kunitz-type proteins or peptides have been found in many blood-sucking animals, but the identity of them in leeches remained elusive. In the present study, five Kunitz-type peptides named WPK1-WPK5 were identified from the leech Whitmania pigra. Recombinant WPK1-WPK5 were expressed in Pichia pastoris GS115, and their inhibitory activity against Factor XIa (FXIa) was tested. WPK5 showed inhibitory activity against FXIa with an IC50 value of 978.20 nM. To improve its potency, the loop replacement strategy was used. The loop 1 (TGPCRSNLER) and loop 2 (QYGGC) in WPK5 were replaced by loop 1 (TGPCRAMISR) and loop 2 (FYGGC) in PN2KPI, respectively, and the resulting peptide named WPK5-Mut showed an IC50 value of 8.34 nM to FXIa, which is about 100-fold the potency of FXIa compared to that of WPK5. WPK5-Mut was further evaluated for its extensive bioactivity in vitro and in vivo. It dose-dependently prolonged APTT on both murine plasma and human plasma, and potently inhibited FeCl3-induced carotid artery thrombosis in mice at a dose of 1.5 mg/kg. Additionally, WPK5-Mut did not show significant bleeding risk at a dose of 6 mg/kg. Together, these results showed that WPK5-Mut is a promising candidate for the development of an antithrombotic drug.

14.
Gastroenterol Res Pract ; 2021: 2425356, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34367275

RESUMEN

BACKGROUND: KLF4 and KLF5 are members of the KLF transcription factor family, which play an important role in many gastrointestinal tumors. To gain a deeper insight into its function and role, bioinformatics was used to analyze the function and role of KLF4 and KLF5 in gastrointestinal tumors. METHODS: Data were collected from several online databases. Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN database analysis, Kaplan-Meier Plotter analysis, LOGpc system, the Pathology Atlas, and the STRING website were used to analyze the data. We download relevant data from TCGA and then perform GO enrichment and KEGG enrichment analysis. The effects of KLF5 on gastric cancer cell proliferation were measured by CCK-8 assay. The effect of KLF5 on the expression of CyclinD1 and MMP9 was detected by Western blot. RESULTS: KLF4 and KLF5 were differentially expressed in normal and tumor tissues of the gastrointestinal tract, and their differential expression is related to several genes or pathways. KEGG analysis showed that KLF5 was coexpressed with endocytosis-related genes. KLF5 promotes the proliferation of gastric cancer cells and the expression of metastasis-related molecules. CONCLUSION: KLF4 and KLF5 are of great significance for developing gastrointestinal tumors and can be used as therapeutic targets.

15.
J Glob Antimicrob Resist ; 27: 41-45, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34438107

RESUMEN

OBJECTIVES: Clostridium perfringens (C. perfringens) can cause intestinal diseases in livestock and humans, which seriously threatens the healthy development of animal husbandry and human food safety. Here, the characteristics of antimicrobial resistance and molecular typing of ruminant-borne strains of C. perfringens in Xinjiang, China were explored and profiled. METHODS: A total of 307 clinical feces collected from ruminants (cattle and sheep) with diarrheal symptoms were screened for C. perfringens. The recovered isolates were characterized in respect to their antimicrobial resistance pattern and molecular typing. RESULTS: A total of 109 isolates of C. perfringens were isolated from 307 clinical feces of ruminants, most of which displayed the multidrug resistance (MDR) phenotype. Demonstration of the quinolone-resistance gene was the highest among the isolates (70.6%). The multiplex PCR typing based on toxin genes showed that type A and type D strains made up 82.6% (90/109) and 17.4% (19/109), among which, the isolates carrying ß2 gene occupied 43.3% (39/90) of type A strains and 31.6% (6/19) of type D strains. These isolates were divided into 6 genotypes (I-VI) by enterobacterial repetitive intergenic consensus sequence-based PCR (ERIC-PCR) method. A total of 33 ST types (ST1-ST33) were identified by multilocus sequence typing (MLST) method. CONCLUSION: C. perfringens isolates with multidrug resistance (MDR) were frequent and circulating in ruminants. Among them, type A-Ⅰ-ST19 was the dominant genotype of C. perfringens, displaying obvious genetic diversity. This study provided important epidemiological data for the risk assessment of food safety associated with ruminant-borne C. perfringens in Xinjiang, China.


Asunto(s)
Infecciones por Clostridium , Clostridium perfringens , Animales , Antibacterianos/farmacología , Bovinos , China/epidemiología , Infecciones por Clostridium/epidemiología , Infecciones por Clostridium/veterinaria , Clostridium perfringens/genética , Farmacorresistencia Bacteriana , Tipificación de Secuencias Multilocus , Rumiantes , Ovinos
16.
Food Chem ; 359: 129899, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33965763

RESUMEN

A low methyl-esterified pectin (33.2% methyl-esterification degree) was isolated from the tuber of Dioscorea opposita Thunb., which was an edible and medicinal material in China. This pectin (Mw of 1.3 × 104 g/mol) contained the ~59.1% homogalacturonan (HG) and ~38.1% highly branched rhamnogalacturonan I (RG-I) region with possible side chains embracing arabinogalactan II, arabinan or arabinogalactan I. The fragments including HG backbone consisting of â†’ 4)-α-GalpA-(1 â†’ and â†’ 4)-α-GalpA-6-O-methyl-(1 â†’ with molar ratio of ~2:1, and repeating unit of arabinogalactan II side chain composed of α-Araf-(1 â†’ and â†’ 3,6)-ß-Galp-(1→, were speculated through methylation analysis and NMR spectra. However, the linkage pattern for RG-I backbone and side chains were indiscernible due to limited resolution of NMR spectra. Besides, the pectin adopted a flexible chain conformation in 0.1 M NaNO3 solution. These results provided a structural basis for study on polysaccharide from D. opposite, which was benefit for development of functional food of yam.


Asunto(s)
Dioscorea/química , Pectinas/aislamiento & purificación , Conformación de Carbohidratos , China , Galactanos/análisis , Galactanos/química , Galactanos/aislamiento & purificación , Pectinas/análisis , Pectinas/química , Plantas Medicinales/química , Polisacáridos/análisis , Polisacáridos/química , Polisacáridos/aislamiento & purificación
17.
Food Res Int ; 143: 110290, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33992390

RESUMEN

Nuclear magnetic resonance (NMR) has been widely used as an analytical chemistry technique to investigate the molecular structure and conformation of polysaccharides. Combined with 1D spectra, chemical shifts and coupling constants in both homo- and heteronuclear 2D NMR spectra are able to infer the linkage and sequence of sugar residues. Besides, NMR has also been applied in conformation, quantitative analysis, cell wall in situ, degradation, polysaccharide mixture interaction analysis, as well as carbohydrates impurities profiling. This review summarizes the principle and development of NMR in polysaccharides analysis, and provides NMR spectra data collections of some common polysaccharides. It will help to promote the application of NMR in complex polysaccharides of biochemical interest, and provide valuable information on commercial polysaccharide products.


Asunto(s)
Polisacáridos , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Conformación Molecular , Resonancia Magnética Nuclear Biomolecular
18.
Pol J Microbiol ; 70(4): 479-487, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35003279

RESUMEN

Salmonella enterica subsp. enterica serovar Typhimurium (ST) is an intracellularly parasitic bacterium. This zoonotic pathogen causes food poisoning and thus imposes a severe threat to food safety. Here, to understand the regulatory roles of the novel transcription factor STM0859 on the response of ST to environmental stress and biofilm formation, the STM0859 gene-deficient strain and the complementation strain ΔSTM0859/STM0859 were generated, respectively. Then, its capacity of responding to environmental stresses and biofilm (BF) formation ability under different stresses, including acid, alkali, high salt, cholate, and oxidative stresses was tested. We further analyzed the interaction between the STM0859 protein and the promoter of the acid stress response-related gene rcsB by performing an electrophoresis mobility shift assay (EMSA). The results showed that acid resistance and BF formation capacities of ST-ΔSTM0859 strain were significantly weaker, as compared with those of Salmonella Typhimurium SL1344 (ST-SL1344) wild strain (p < 0.01). Quantitative qRT-PCR analysis showed that the expression levels of acid stress and BF formation-related genes, rcsB and rpoS, of ST-ΔSTM0859 strain were significantly reduced at the transcription levels, while the transcription levels of these genes were fully restored in complementation strain ST-ΔSTM0859/STM0859. The results of EMSA showed that STM0859 was capable of binding the promoter DNA fragments of the rcsB gene, suggesting that STM0859 can promote the transcription of the rcsB gene through interaction with its promoter, thereby exerting an indirectly regulatory role on the adaptive responses to acid stress and BF formation of ST. This study provided new insights into the regulatory mechanisms of the LysR family factors on the tolerances of ST under adverse environmental stresses.


Asunto(s)
Salmonella typhimurium , Estrés Fisiológico , Proteínas Bacterianas/metabolismo , Biopelículas , Regulación Bacteriana de la Expresión Génica , Salmonella typhimurium/genética , Factores de Transcripción/genética
19.
J Vet Res ; 64(4): 509-515, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33367139

RESUMEN

INTRODUCTION: Gastrointestinal parasites are some of the most common pathogens which are seriously harmful to the camel's health. The infection status of gastrointestinal parasites in camels (Camelus bactrianus) in the Tianshan Mountains pastoral area in China is still unclear. The aim of this study was to investigate the species and infection intensity of gastrointestinal tract parasites in local camels. MATERIAL AND METHODS: A total of 362 fresh faecal samples were collected and examined for parasite eggs using the saturated saline floating and natural sedimentation method. The parasite eggs were subjected to morphological and molecular examination and identification, and the infection rate and mean intensity of the parasites were analysed. RESULTS: A total of 15 gastrointestinal tract parasite species' eggs were identified, with a detection rate of 100%. Ostertagia spp. (100%) and Trichostrongylus spp. (98.1%) were dominant. Camels were often coinfected by 5-14 species. The average number of eggs per gram of faeces was higher for Ostertagia spp. (298), Haemonchus contortus (176) and Nematodirus spp. (138). The number of species of parasites infecting young camels was significantly lower than that of adult camels, but the infection intensity in young camels was significantly higher. CONCLUSION: Gastrointestinal parasites were highly prevalent in camels from the Tianshan Mountains pastoral area in China. This finding provides important epidemiological data for the prevention and control of associated infections in camels.

20.
Vet World ; 13(5): 916-922, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32636588

RESUMEN

BACKGROUND AND AIM: As a tick-borne zoonotic pathogen, Ehrlichia canis has already posed a threat to public health and safety. This study aimed to clarify the prevalence and molecular characteristics of E. canis in pet dogs in Xinjiang, China. MATERIALS AND METHODS: A total of 297 blood samples of pet dogs and 709 skin ticks (Rhipicephalus sanguineus sensu lato) were subjected to molecular detection using PCR for E. canis 16S rRNA gene, and then, positive samples were amplified, sequenced, and phylogenetically analyzed for E. canis gp36 gene. RESULTS: The PCR detection showed that the positive rate of PCR was 12.12% (36/297) in blood samples and 15.23% (108/709) in tick samples, respectively. Based on the phylogenetic analysis of E. canis gp36 protein, these E. canis strains in different geographical regions of the world can be divided into Genogroup I and Genogroup II. Among them, the Xinjiang epidemic strain XJ-6 and 533, 36, 1055, Kasur1, and Jake strains were clustered into subgroup 1.1 of Genogroup I, while the XJ-2, XJ-21, and XJ-35 strains and the TWN1, TWN4, CM180, and CM196 strains were closely related and belonged to subgroup 2.2 of Genogroup II, displaying high genetic diversity. CONCLUSION: This is the first study focusing on the molecular epidemiology of E. canis infection in pet dogs, which revealed that E. canis infection had been occurred in Xinjiang, China. More importantly, this study confirmed that the substantial variability in immunoreactive protein gp36 from E. canis strains circulating in pet dogs.

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