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1.
Food Chem ; 306: 125615, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31622833

RESUMO

Phycocyanin (PC), a plant-based protein with interesting biological activity, is rarely directly applied in the food industry because it has structural and functional limitations. This study combined ultra-high-pressure (UHP) treatment with glycation to improve PC functionality and explored resulting structural changes using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, scanning electron microscopy, Fourier-transform infrared spectroscopy, circular dichroism, and UV-visible spectroscopy. The UHP treatment obviously improved the speed and degree of glycation and the composite-modified PC (CM-PC) showed high solubility and good emulsifying and foaming performance. Scanning electron microscopy images showed the CM-PC surface was loose and fluffy. Gel electrophoresis, Fourier-transform infrared spectroscopy, and circular dichroism results demonstrated that the content of α-helix decreased from 78.1% in PC to 26.6% in CM-PC, and hydroxyl groups were introduced. UV-visible spectroscopy showed that the mechanism of composite modification involved stretching of the PC and promotion of binding with sugars.

2.
Sensors (Basel) ; 19(21)2019 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-31717856

RESUMO

To improve the multi-speed adaptability of the powered prosthetic knee, this paper presented a speed-adaptive neural network control based on a powered geared five-bar (GFB) prosthetic knee. The GFB prosthetic knee is actuated via a cylindrical cam-based nonlinear series elastic actuator that can provide the desired actuation for level-ground walking, and its attitude measurement is realized by two inertial sensors and one load cell on the prosthetic knee. To improve the performance of the control system, the motor control and the attitude measurement of the GFB prosthetic knee are run in parallel. The BP neural network uses input data from only the GFB prosthetic knee, and is trained by natural and artificially modified various gait patterns of different able-bodied subjects. To realize the speed-adaptive control, the prosthetic knee speed and gait cycle percentage are identified by the Gaussian mixture model-based gait classifier. Specific knee motion control instructions are generated by matching the neural network predicted gait percentage with the ideal walking gait. Habitual and variable speed level-ground walking experiments are conducted via an able-bodied subject, and the experimental results show that the neural network control system can handle both self-selected walking and variable speed walking with high adaptability.

3.
Acta Pharmacol Sin ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31705124

RESUMO

Stem cell therapy represents the potential alternative effective strategy for some diseases that lack effective treatment currently. Correspondingly, it is crucial to establish high-sensitive and reliable quantification assay for tracing exogenous cell migration. In the present study, we first used both bioluminescence imaging (BLI) indirect labeling (human norepinephrine transporter-luciferase reporter system) and 89zirconium (89Zr)-hNSCs direct labeling combined with positron emission tomography/computer tomography (PET/CT) system for tracking human neural stem cells (hNSCs) migration into the brain via nasal administration in preclinical study. But the above two methods failed to give the biodistribution profile due to their low sensitivity. Considering its superior sensitivity and absolute quantitation capability, we developed and validated the droplet digital PCR (ddPCR) targeting species-specific gene in frozen and paraffin sections, slices, and whole blood with the sensitivity of 100-200 hNSCs. Accurate and high throughput quantification could be performed using ddPCR with the coefficient of variation (CVs) of lower quality control (LQC) below 30%. In combination with immunohistochemistry and ddPCR, we confirmed the migration of hNSCs into the brain via nasal administration, which supported the efficacy of hNSCs in MPTP-treated mice, an animal model of Parkinson's disease. In conclusion, the present study is the first to report the application of ddPCR in the pharmacokinetics profile description of tracking of hNSCs in preclinical studies.

4.
Pflugers Arch ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31709454

RESUMO

MicroRNA 495 (miR-495) has been discovered to be involved in the metabolism and immune response in human body. The purpose of this study was to investigate the effect of miR-495 on macrophage M1/M2 polarization and insulin resistance in type 2 diabetes (T2D). A T2D mouse model was established by feeding C57BL/6 mice with a high-fat diet (HFD). The expressions of M1/M2 polarization markers and miR-495 in peritoneal macrophages were determined by qRT-PCR or Western blot. Mouse insulin tolerance test (ITT) and glucose tolerance test (GTT) were performed, and the targeted binding effect between miR-495, fat mass, and obesity-associated gene (FTO) was verified by double luciferase gene reporter assay. The body weight, blood glucose content, and miR-495 expression in macrophages of the HFD group were remarkably higher than those of the normal diet (ND) group. Besides, miR-495 induced the transformation of macrophages into M1-type pro-inflammatory macrophages and enhanced the insulin resistance of T2D mice. More importantly, FTO was proved to be a direct target gene of miR-495 and silencing FTO could induce the transformation of macrophages into M1-type pro-inflammatory macrophages. These results demonstrated that miR-495 could promote the transformation of macrophages into M1-type pro-inflammatory macrophages by inhibiting the expression of its target gene FTO, and aggravate the insulin resistance and adipose tissue inflammation in T2D mice, which provided a certain theoretical basis for the targeted treatment of T2D.

5.
Biomolecules ; 9(12)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766534

RESUMO

Inflammatory bowel disease (IBD) is general term for ulcerative colitis and Crohn's disease, which is chronic intestinal and colorectal inflammation caused by microbial infiltration or immunocyte attack. IBD is not curable, and is highly susceptible to develop into colorectal cancer. Finding agents to alleviate these symptoms, as well as any progression of IBD, is a critical effort. This study evaluates the anti-inflammation and anti-tumor activity of 16-hydroxycleroda-3,13-dien-15,16-olide (HCD) in in vivo and in vitro assays. The result of an IBD mouse model induced using intraperitoneal chemical azoxymethane (AOM)/dextran sodium sulfate (DSS) injection showed that intraperitoneal HCD adminstration could ameliorate the inflammatory symptoms of IBD mice. In the in vitro assay, cytotoxic characteristics and retained signaling pathways of HCD treatment were analyzed by MTT assay, cell cycle analysis, and Western blotting. From cell viability determination, the IC50 of HCD in Caco-2 was significantly lower in 2.30 µM at 48 h when compared to 5-fluorouracil (5-FU) (66.79 µM). By cell cycle and Western blotting analysis, the cell death characteristics of HCD treatment in Caco-2 exhibited the involvement of extrinsic and intrinsic pathways in cell death, for which intrinsic apoptosis was predominantly activated via the reduction in growth factor signaling. These potential treatments against colon cancer demonstrate that HCD could provide a promising adjuvant as an alternative medicine in combating colorectal cancer and IBD.

6.
Int J Cardiol ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31767387

RESUMO

BACKGROUND: Systolic blood pressure increased in middle-aged person contributes significantly to the risk of major adverse cardiovascular events (MACE). Meanwhile, different patterns (short- or long-term change) of SBP increase may result in differential risk and lead to differences in predictive ability. METHODS: A total of 19,544 and 22,610 participants in the Fuxin Cardiovascular Cohort Study underwent measurement of SBP at 2 examinations for short- and long-term change study population. Cox proportional hazards models were used to relate future clinical outcomes with change in SBP. RESULTS: During a median follow-up period of 12.5 years, 1064 (772 stroke, 247 myocardial infarction, 528 CVD deaths) and 1316 (958 stroke, 301 myocardial infarction, 660 CVD deaths) MACE were identified during short- and long-terms SBP change, respectively. For SBP increased participants, short-term change in SBP was associated with future MACE (hazard ratio [HR]: 1.241 per 1-SD increase; 95% confidence interval [CI]: 1.146-1.344; P < 0.001), long-term change in SBP (HR: 1.218; 95% CI: 1.123-1.322; P < 0.001). For prehypertension participants, long-term changes conferred a strong impact than short-term. For hypertensive participants, short-term changes conferred a strong impact than long-term. CONCLUSIONS: Having a SBP rise in short- or long-term both confer an increased risk of MACE and its subgroups. Furthermore, short- and long-term SBP increase patterns adds different additional information beyond one single baseline examination. Change in SBP may be a prognostic surrogate marker and future studies are needed to clarify the possible mechanism for predicting MACE.

7.
J Hum Hypertens ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666663

RESUMO

This study aimed to investigate the effect of body mass index (BMI) changes on hypertension among rural areas of China. A population-based sample of 13,263 and 5944 rural Chinese people aged ≥35 years and without hypertension at baseline was included in our analysis of BMI changes (from (2004-2006) to 2008) and short- and long-term outcomes of hypertension (from 2008 to 2010 and 2010 to 2017). The participants were divided into four groups by a comprehensive cross-sectional combination according to baseline BMI (18.5-24 vs. ≥24 kg/m2) and follow-up changes (decreased vs. increased). Adjusted Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs). During a median follow-up period of 4.8 (short-term) and 11.7 (long-term) years, 2299 (17.33%) and 2020 (33.98%) participants developed hypertension, respectively. For participants with a baseline BMI ≥ 24 kg/m2, when BMI decreased in follow-ups, the multivariable-adjusted HRs (95% CI) of short-term hypertension were 0.898 (0.857-0.942). For baseline 18.5 kg/m2 ≤ BMI < 24 kg/m2, when BMI increased in follow-ups, the risks of short-term hypertension were 1.103 (1.068-1.139). We detected that BMI changes had a lower impact on the incidence of hypertension in long-term than short-term. Our study indicated that BMI changes were significantly associated with the incidence of hypertension for the short-term, and it had a stronger impact on short-term outcomes than long-term. Managing weight by lifestyle modification was particularly important for the primary prevention of hypertension in rural Chinese population.

8.
Int J Mol Sci ; 20(22)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31739570

RESUMO

The WRKY transcription factor superfamily is known to participate in plant growth and stress response. However, the role of this family in wheat (Triticum aestivum L.) is largely unknown. Here, a salt-induced gene TaWRKY13 was identified in an RNA-Seq data set from salt-treated wheat. The results of RT-qPCR analysis showed that TaWRKY13 was significantly induced in NaCl-treated wheat and reached an expression level of about 22-fold of the untreated wheat. Then, a further functional identification was performed in both Arabidopsis thaliana and Oryza sativa L. Subcellular localization analysis indicated that TaWRKY13 is a nuclear-localized protein. Moreover, various stress-related regulatory elements were predicted in the promoter. Expression pattern analysis revealed that TaWRKY13 can also be induced by polyethylene glycol (PEG), exogenous abscisic acid (ABA), and cold stress. After NaCl treatment, overexpressed Arabidopsis lines of TaWRKY13 have a longer root and a larger root surface area than the control (Columbia-0). Furthermore, TaWRKY13 overexpression rice lines exhibited salt tolerance compared with the control, as evidenced by increased proline (Pro) and decreased malondialdehyde (MDA) contents under salt treatment. The roots of overexpression lines were also more developed. These results demonstrate that TaWRKY13 plays a positive role in salt stress.

9.
J Int Assoc Provid AIDS Care ; 18: 2325958219888457, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31750768

RESUMO

BACKGROUND: Tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is a strong predictor of viral suppression in persons living with HIV (PLWH). Its association with antiretroviral therapy (ART) resistance remains unknown. METHODS: Blood was collected in PLWH receiving TDF-containing ART enrolled in a 48-week study. Tenofovir diphosphate/emtricitabine triphosphate (FTC-TP) were quantified from the same sample as HIV viral load (VL) in PLWH who developed resistance within ≤12 months. RESULTS: The study enrolled 807 participants, of whom 10 had new resistance-conferring mutations. Among these, median (interquartile range) TFV-DP and HIV VL were 956 (407-1510) fmol/punch and 9840 (513-68,200) copies/mL, respectively. Five had quantifiable FTC-TP in DBS. Based on previously published data, a TFV-DP concentration of 956 fmol/punch would have an adjusted odds of virologic suppression of 32.8 versus TFV-DP <350 fmol/punch, making viremia of ∼10,000 copies/mL an unexpected outcome. CONCLUSION: Moderately high TFV-DP in DBS (700-1249 fmol/punch) in PLWH with high viremia suggest that antiretroviral drug resistance might be present.

10.
BMC Cardiovasc Disord ; 19(1): 258, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747878

RESUMO

BACKGROUND: The new ACC/AHA hypertension guideline lower the definition of hypertension from 140/90 mmHg to 130/80 mmHg and eliminate the category of prehypertension thus increasing the prevalence of hypertension. A purpose of this study is to explore the applicability of the new guidelines in rural China. METHODS: In total, 3229 participants aged ≥35 years and free of stroke at baseline were followed for up to 4.8 years during 2012 to 2017 in a rural community-based prospective cohort study of Xifeng County. The hazard ratio (HR) and 95% Confidence interval (CI) of different blood pressure (BP) levels for risk of incident stroke were analyzed by multivariable Cox proportional hazard models. RESULTS: During the follow-up, 81 new strokes occurred among the 3229 participants. Compared with normal BP (Systolic BP (SBP)<120 mmHg and Diastolic BP (DBP)<80 mmHg), stage 2 hypertension (SBP ≥ 140 mmHg or DBP ≥ 90 mmHg) had approximately 2.1 greater risks for stroke (HR: 2.10, 95% CI: 1.13 to 3.91, P = 0.020). However, there was no significant association between elevated (SBP:120-129 mmHg and DBP<80 mmHg), stage1 hypertension (SBP:130-139 mmHg or DBP:80-89 mmHg) and stroke incidence (HR: 0.93, 95% CI: 0.33 to 2.61, P = 0.888; HR: 0.96, 95% CI: 0.46 to 2.02, P = 0.920, respectively). An increase of the SBP by 1-SD increases the risk for stroke by 56% (HR: 1.56, 95%CI: 1.29 to 1.88, P < 0.001). An increase of the SBP by 20 mmHg increases the risk for stroke by 51% (HR: 1.51, 95%CI: 1.27 to 1.80, P < 0.001). CONCLUSIONS: Compared with normal BP, the stage 2 hypertension based on 2017 ACC/AHA guideline significantly increases the risk of stroke incidence, but this association was not observed between elevated, stage1 hypertension and stroke incidence in Chinese rural adults.

11.
BMC Plant Biol ; 19(1): 506, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747904

RESUMO

BACKGROUND: Ethylene-responsive factors (ERFs) play important roles in plant growth and development and the response to adverse environmental factors, including abiotic and biotic stresses. RESULTS: In the present study, we identified 160 soybean ERF genes distributed across 20 chromosomes that could be clustered into eight groups based on phylogenetic relationships. A highly ABA-responsive ERF gene, GmERF75, belonging to Group VII was further characterized. Subcellular localization analysis showed that the GmERF75 protein is localized in the nucleus, and qRT-PCR results showed that GmERF75 is responsive to multiple abiotic stresses and exogenous hormones. GmERF75-overexpressing Arabidopsis lines showed higher chlorophyll content compared to WT and mutants under osmotic stress. Two independent Arabidopsis mutations of AtERF71, a gene homologous to GmERF75, displayed shorter hypocotyls, and overexpression of GmERF75 in these mutants could rescue the short hypocotyl phenotypes. Overexpressing GmERF75 in soybean hairy roots improved root growth under exogenous ABA and salt stress. CONCLUSIONS: These results suggested that GmERF75 is an important plant transcription factor that plays a critical role in enhancing osmotic tolerance in both Arabidopsis and soybean.

12.
BMC Nephrol ; 20(1): 435, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31771524

RESUMO

BACKGROUND: Experimental studies have demonstrated that hypersecretion of growth hormone (GH) is associated with development of glomerular sclerosis. However, clinical case of such condition is very rare. Here we presented a case of focal segmental glomerulosclerosis (FSGS) associated with acromegaly. CASE PRESENTATION: A 63-year-old man was diagnosed as nephrotic syndrome with minimal change disease for 2 years. Prednisone 1 mg/kg/day for 9 months led to no response. After admission, the second kidney biopsy indicated FSGS (NOS variant). On admission, his acromegalic features were noticed and he complained with a 20-year history of soft tissue swelling of hands and feet. Serum GH and insulin-like growth factor 1 (IGF-1) concentrations were both elevated significantly. An oral glucose tolerance test showed inadequate suppression of serum GH. The presence of a pituitary macroadenoma with a diameter of 1.4 cm by MRI confirmed the diagnosis of acromegaly. Then, the tumor was subtotally removed by trans-sphenoidal surgery. Partial remission of proteinuria was achieved 3 months after surgery and maintained during follow-up, with gradual reduce of corticosteroid. CONCLUSIONS: This rare case suggested that the hypersecretion of GH may participate, at least in part, in FSGS development and progression. Early diagnosis and treatment of acromegaly is beneficial.

13.
Org Lett ; 21(20): 8439-8443, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31596103

RESUMO

A straightforward approach for the assembly of different polysubstituted propiolamidnates via palladium-catalyzed multicomponent reaction of isocyanides, haloalkynes, and amines has been reported in which the C(sp)-C(sp2) and C(sp2)═N bonds were constructed in one pot. This reaction featured in high efficiency, excellent chemoselectivity, and good functional group compatibility. The synthetic utility of this method was also demonstrated.

14.
World J Surg ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31637507

RESUMO

BACKGROUND: The prognostic significance of preoperative plasma fibrinogen in patients with operable gastric cancer remains under debate. This study aimed to elucidate the prognostic value of fibrinogen in gastric cancer patients underwent gastrectomy. METHODS: A total of 4351 patients with gastric cancer collected from three comprehensive medical centers were retrospectively evaluated. Patients were categorized by minimum P value using X-tile, while the baseline confounders for fibrinogen was balanced through propensity score matching (PSM). The relationships between fibrinogen and other clinicopathologic features were evaluated, and nomogram was constructed to assess its prognostic improvement compared with TNM staging system. RESULTS: Fibrinogen was significantly correlated with macroscopic type, tumor differentiation, tumor size, and T and N stage. The factors, fibrinogen and T stage as well as N stage, were identified to be independent prognostic factors after PSM. Nomogram based on fibrinogen demonstrated a smaller Akaike information criterion (AIC) and a larger concordance index (C-index) than TNM staging system, illustrating that fibrinogen might be able to improve the prognostic accuracy. CONCLUSIONS: Preoperative plasma fibrinogen levels in gastric cancer patients were significantly correlated with tumor progression, which could be regarded as a reliable marker for survival prognostic prediction.

15.
J Biotechnol ; 306: 149-158, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31568802

RESUMO

Colorectal cancer is a leading cause of death in the world. Despite the progress in therapeutic development, there are still challenges in clinical practice. Nanomedicine has emerged as a solution to enhance traditional therapy. Gold nanoparticles (AuNP) have been demonstrated as potential appliance in treating cancers, yet few studies investigated the capacity of biopolymer-conjugated AuNP in colon cancer as well as examined the system in both cancer cell line and animal models. In this study, we designed the AuNP/biopolymer composite therapeutic system with a chemotherapy agent, doxorubicin (DOX). Two composites with different drug load were applied (referred to as AuPPPyA and AuPPPyB). The composites were characterized by UV spectrum, transmission electron microscope (TEM), zeta potential measurement, and cell cycle analysis. Both therapeutic systems exhibited superior cytotoxic effects compared to DOX alone group. Compatible results were also demonstrated in vivo, as tumor inhibition rate were 46.2% in AuPPPyA and 66.4% in AuPPPyB, which were both higher than that of DOX alone (30%). Cell cycle regulation mediated by our composites was also examined in our study. In conclusion, our data demonstrated that AuNP/biopolymer composites are powerful in treating KRAS gene mutated colorectal cancer, and the system could potentially contribute to other clinical refractory diseases in the future.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31595640

RESUMO

Single-ligand-based electronically conductive porous coordination polymers/metal-organic frameworks (EC-PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π-conjugated EC-MOF containing copper units with mixed trigonal ligands was developed: Cu3 (HHTP)(THQ) (HHTP=2,3,6,7,10,11-hexahydrotriphenylene, THQ=tetrahydroxy-1,4-quinone). The modulated conductivity (σ≈2.53×10-5  S cm-1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g-1 ) of the Cu3 (HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor.

17.
J Ethnopharmacol ; 248: 112306, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31626909

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine Leonurus japonicus Houtt. has a long history in the treatment of cardiovascular diseases. Stachydrine hydrochloride, the main bioactive ingredient extracted from Leonurus japonicus Houtt., has been shown to have cardioprotective effects. However, the underlying mechanisms of stachydrine hydrochloride haven't been comprehensively studied so far. AIM OF THE STUDY: The aim of this study was to investigate the protective role of stachydrine hydrochloride in heart failure and elucidate its possible mechanisms of action. MATERIALS AND METHODS: In vivo, transverse aorta constriction was carried out in C57BL/6J mice, and thereafter, 7.2 mg/kg telmisartan (a selective AT1R antagonist as positive control) and 12 mg/kg stachydrine hydrochloride was administered daily intragastrically for 4 weeks. Cardiac function was evaluated by assessing morphological changes as well as echocardiographic and haemodynamic parameters. In vitro, neonatal rat cardiomyocytes or adult mice cardiomyocytes were treated with stachydrine hydrochloride and challenged with phenylephrine (α-AR agonist). Ventricular myocytes were isolated from the hearts of C57BL/6J mice by Langendorff crossflow perfusion system. Intracellular calcium was measured by an ion imaging system. The length and movement of sarcomere were traced to evaluate the systolic and diastolic function of single myocardial cells. RESULTS: Stachydrine hydrochloride improved the cardiac function and calcium transient amplitudes, and inhibited the SR leakage and the amount of sparks in cardiac myocytes isolated from TAC mice. We also demonstrated that stachydrine hydrochloride could ameliorated phenylephrine-induced enhance in sarcomere contraction, calcium transients and calcium sparks. Moreover, our data shown that stachydrine hydrochloride blocked the hyper-phosphorylation of CaMKII, RyR2, PLN, and prevented the disassociation of FKBP12.6 from RyR2. CONCLUSION: Our results suggest that stachydrine hydrochloride exerts beneficial therapeutic effects against heart failure. These cardioprotective effects may be associated with the regulation of calcium handling by stachydrine hydrochloride through inhibiting the hyper-phosphorylation of CaMKII.

18.
Nat Commun ; 10(1): 4362, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554816

RESUMO

Direct structural information of confined CO2 in a micropore is important for elucidating its specific binding or activation mechanism. However, weak gas-binding ability and/or poor sample crystallinity after guest exchange hindered the development of efficient materials for CO2 incorporation, activation and conversion. Here, we present a dynamic porous coordination polymer (PCP) material with local flexibility, in which the propeller-like ligands rotate to permit CO2 trapping. This process can be characterized by X-ray structural analysis. Owing to its high affinity towards CO2 and the confinement effect, the PCP exhibits high catalytic activity, rapid transformation dynamics, even high size selectivity to different substrates. Together with an excellent stability with turnover numbers (TON) of up to 39,000 per Zn1.5 cluster of catalyst after 10 cycles for CO2 cycloaddition to form value-added cyclic carbonates, these results demonstrate that such distinctive structure is responsible for visual CO2 capture and size-selective conversion.

19.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3046-3056, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529880

RESUMO

This study evaluated the changes of spatial distribution of the constructive species Stipa breviflora in the desert steppe under different grazing intensities (control, light, moderate, and heavy grazing) in Siziwang, Inner Mongolia. The small-scale spatial distribution of S. breviflora was measured. Results showed that population density of S. breviflora was following the order: heavy grazing (27.81 individuals·m-2) > moderate grazing (22.17 individuals·m-2) > control (11.31 individuals·m-2) > light grazing (10.76 individuals·m-2). The moderate and heavy grazing significantly increased population density of S. breviflora. According to the model fitting by semi-variance function, the population density of S. breviflora under the control, light, moderate and heavy gra-zing treatments were consistent with the exponential model, spherical model, exponential model and spherical model, respectively. Results from spatial distribution pattern analysis showed that structural ratio of S. breviflora population was control (99.7%) > heavy grazing (94.7%) > light grazing (92.7%) > moderate grazing (87.9%). Such a result indicated that the spatial autocorrelation of the four treatments was high, which were mainly affected by structural factors. In comparison, S. breviflora population structure ratio under moderate grazing treatment was the smallest, and partly affected by random factors. Based on fractal dimension analysis, spatial structure of the four treatments was good with simple spatial distribution. With the increases of grazing intensity, the spatial distribution was simpler and more homogeneous. Combined with 2D and 3D views, both light and heavy grazing changed spatial distribution of S. breviflora population from gradient distribution to patch distribution and resulted in the reduction of spatial heterogeneity.


Assuntos
Ecossistema , Meio Ambiente , Herbivoria , Poaceae/fisiologia , China , Análise Espacial
20.
Pharmacol Res ; 149: 104459, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31541689

RESUMO

Gut microbiota and their metabolites (short-chain fatty acids, SCFAs) are associated with the pathogenesis of rheumatoid arthritis (RA). Total Clematis triterpenoid saponins (CTSs) prepared from Clematis mandshurica Rupr. possess therapeutic benefits for arthritic diseases. However, the poor pharmacokinetic properties of CTSs have obstructed the translation of these natural agents to drugs. Here, we examined the effects of CTSs on arthritis symptoms, gut microbiota and SCFAs in rats with collagen-induced arthritis (CIA). Our results showed that the arthritis index scores of CIA rats treated with CTSs were significantly lower than those of the model group. Most importantly, CTSs moderated gut microbial dysbiosis and significantly downregulated the total SCFA concentration in CIA rats. Compared to the control group, CTSs treatment have no significant side effects on the gut microbiota and SCFA metabolism in normal rats. Two differential analyses (LEfSe and DESeq2) were combined to study the details of the changes in gut microbiome, and twenty-four marker taxa at the genus level were identified via a comparison among control, model and CIA rats treated with high doses of CTSs. In particular, the mostly significantly increased gram-negative (G-) and decreased gram-positive (G+) genera in CIA rats were well restored by CTSs. The observed SCFA concentrations demonstrated that CTSs tend to maintain the balance of the gut microbiota. The data presented herein suggest that CTSs could ameliorate arthritis-associated gut microbial dysbiosis and may be potential adjuvant drugs that could provide relief from the gastrointestinal damage caused as a side effect of commonly used drugs.

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