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1.
Huan Jing Ke Xue ; 44(9): 4853-4862, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699804

RESUMO

Studies on runoff are crucial for the scientific allocation, utilization, and development of water resources and can provide an important basis for the prevention and control of flood and drought disaster, as well as water environmental pollution management. Affected by global warming, the frequency and intensity of extreme climate events, particularly extreme precipitation, have significantly changed in recent years, which can directly or indirectly impact runoff changes. In this study, we used the SWAT model to simulate the spatiotemporal variations in runoff in the Yangtze River Basin from 1965 to 2019 and analyzed the response of runoff to precipitation under extreme conditions. The results showed that the changes in total runoff in the Yangtze River Basin were not significantly different from 1965 to 2019. The total runoff and the mid-lower runoff in the basin experienced four stages of "dry-wet-dry-wet." Simulations revealed that under the 50-year extreme precipitation event, the increase in daily average runoff was 6200%, 21%, and 15% for the typical sub-basins of the upper, middle, and lower reaches of the Yangtze River, respectively. Additionally, the increase in monthly and annual average runoff was 355%, 5%, and 1.3% and 78%, 1%, and 0.24%, for upper, middle, and lower reaches of the Yangtze River, respectively. Moreover, under the 100-year extreme precipitation, the average daily runoff increasing rates were 8000%, 25%, and 17% for upper, middle, and lower reaches of the Yangtze River, respectively, compared to the monthly increase of 437%, 7%, and 1.5% and annual increase of 96%, 1.2%, and 0.28%, respectively. Our findings may improve the understanding of hydrological responses to climate change and provide valuable inferences to decision-makers and water managers for better allocation and management of water resources.

2.
Physiol Mol Biol Plants ; 29(1): 11-22, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36733836

RESUMO

Saline-alkali stress is a universal abiotic stress factor limiting fruit tree cultivation worldwide. Apple (Malus×domestica Borkh.) is one of the fruits with the largest yields worldwide. Tea crabapple (Malus hupehensis Rehd. var. pingyiensis Jiang) is a type of common apple rootstock in China. Because facultative apomixis occurs in this species, it is often used in molecular research. The present study investigated the molecular mechanism of the response of indoleacetic acid (IAA) and cytokinins [zeatin, trans-zeatin riboside (tZR), isopentenyladenine (iP), and isopentenyladenosine (iPA)] to mixed saline-alkali stress (MSAS) in tea crabapple leaves. The endogenous hormone content of tea crabapple leaves under MSAS was measured, and the expression of stress response-related genes was analyzed by RNA sequencing. The results showed that the concentration of IAA was initially higher and then lower than that in the control, whereas the concentration of zeatin, tZR, iP, and iPA was higher than that in the control. A total of 1262 differentially expressed genes were identified in the three comparison groups. Further analyses suggested that IAA and cytokinin biosynthetic genes were mostly upregulated in tea crabapple leaves, indicating that auxin and cytokinin signaling pathway regulation occurred in response to MSAS. These findings suggest that IAA and cytokinins play an important role in the response of tea crabapple to MSAS. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01275-4.

3.
Microb Biotechnol ; 16(4): 799-812, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36528874

RESUMO

Hypertension is a significant risk factor of cardiovascular diseases (CVDs) with high prevalence worldwide, the current treatment has multiple adverse effects and requires continuous administration. The glucagon-like peptide-1 receptor (GLP-1R) agonists have shown great potential in treating diabetes mellitus, neurodegenerative diseases, obesity and hypertension. Butyric acid is a potential target in treating hypertension. Yet, the application of GLP-1 analogue and butyric acid in reducing blood pressure and reversing ventricular hypertrophy remains untapped. In this study, we combined the therapeutic capability of GLP-1 and butyric acid by transforming Clostridium butyricum (CB) with recombinant plasmid pMTL007 encoded with hGLP gene to construct the engineered probiotics Clostridium butyricum-pMTL007-GLP-1 (CB-GLP-1). We used spontaneous hypertensive rat (SHR) models to evaluate the positive effect of this strain in treating hypertension. The results revealed that the intragastric administration of CB-GLP-1 had markedly reduced blood pressure and improved cardiac marker ACE2, AT2R, AT1R, ANP, BNP, ß-MHC, α-SMA and activating AMPK/mTOR/p70S6K/4EBP1 signalling pathway. The high-throughput sequencing further demonstrated that CB-GLP-1 treatments significantly improved the dysbiosis in the SHR rats via downregulating the relative abundance of Porphyromonadaceae at the family level and upregulating Lactobacillus at the genus level. Hence, we concluded that the CB-GLP-1 greatly improves blood pressure and cardiomegaly by restoring the gut microbiome and reducing ventricular hypertrophy in rat models. This is the first time using engineered CB in treating hypertension, which provides a new idea for the clinical treatment of hypertension.


Assuntos
Clostridium butyricum , Microbioma Gastrointestinal , Hipertensão , Probióticos , Ratos , Animais , Pressão Sanguínea/fisiologia , Peptídeo 1 Semelhante ao Glucagon/genética , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Ratos Endogâmicos SHR , Microbioma Gastrointestinal/fisiologia , Clostridium butyricum/metabolismo , Ácido Butírico/farmacologia , Hipertensão/terapia , Hipertrofia
4.
Neural Regen Res ; 18(3): 577-581, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36018180

RESUMO

Axon regeneration of central neurons is a complex process that is tightly regulated by multiple extrinsic and intrinsic factors. The expression levels of distinct genes are changed after central neural system (CNS) injury and affect axon regeneration. A previous study identified dusp2 as an upregulated gene in zebrafish with spinal cord injury. Here, we found that dual specificity phosphatase 2 (DUSP2) is a negative regulator of axon regeneration of the Mauthner cell (M-cell). DUSP2 is a phosphatase that mediates the dephosphorylation of JNK. In this study, we knocked out dusp2 by CRISPR/Cas9 and found that M-cell axons of dusp2-/- zebrafish had a better regeneration at the early stage after birth (within 8 days after birth), while those of dusp2+/- zebrafish did not. Overexpression of DUSP2 in Tg (Tol 056) zebrafish by single-cell electroporation retarded the regeneration of M-cell axons. Western blotting results showed that DUSP2 knockout slightly increased the levels of phosphorylated JNK. These findings suggest that knocking out DUSP2 promoted the regeneration of zebrafish M-cell axons, possibly through enhancing JNK phosphorylation.

5.
Nat Commun ; 12(1): 7168, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34887407

RESUMO

Krill and salps are important for carbon flux in the Southern Ocean, but the extent of their contribution and the consequences of shifts in dominance from krill to salps remain unclear. We present a direct comparison of the contribution of krill and salp faecal pellets (FP) to vertical carbon flux at the Antarctic Peninsula using a combination of sediment traps, FP production, carbon content, microbial degradation, and krill and salp abundances. Salps produce 4-fold more FP carbon than krill, but the FP from both species contribute equally to the carbon flux at 300 m, accounting for 75% of total carbon. Krill FP are exported to 72% to 300 m, while 80% of salp FP are retained in the mixed layer due to fragmentation. Thus, declining krill abundances could lead to decreased carbon flux, indicating that the Antarctic Peninsula could become a less efficient carbon sink for anthropogenic CO2 in future.


Assuntos
Ciclo do Carbono , Carbono/metabolismo , Euphausiacea/metabolismo , Água do Mar/análise , Animais , Regiões Antárticas , Fezes/química
7.
J Int Med Res ; 48(7): 300060520943792, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32721183

RESUMO

OBJECTIVE: To investigate the anti-proliferative and pro-apoptotic effects of curcumin on diffuse large B-cell lymphoma (DLBCL) cells and explore the mechanism. METHODS: OCI-LY7 cells were treated with curcumin (2.5, 5, 10, 20, and 40 µM) for 24, 48, or 72 hours. Cell viability and apoptosis were determined using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5 diphenyl tetrazolium bromide assay and TdT-mediated dUTP nick-end labeling staining, respectively. MiR-28-5p expression was detected via qRT-PCR. The binding site of miR-28-5p was predicted using online databases and verified using the dual-luciferase reporter assay. MiR-28-5p overexpression and inhibition were achieved via transfection with an miR-28-5p mimic and inhibitor, respectively. RESULTS: Curcumin decreased the viability of OCI-LY7 cells in a concentration- and time-dependent manner, and these effects were attenuated by miR-28-5p inhibition. MiR-28-5p expression was upregulated by curcumin. Curcumin increased the numbers of apoptotic cells and upregulated cleaved caspase-3 expression, and these effects were attenuated by miR-28-5p inhibition. The dual-luciferase reporter assay confirmed that miR-28-5p directly targets the 3'-untranslated region of BECN1. Curcumin downregulated BECN1 and microtubule-associated protein 1 light chain 3 beta-II/I expression and upregulated p62 expression. CONCLUSIONS: Our results described the curcumin exerted anti-proliferative and pro-apoptotic effects on OCI-LY7 cells through a mechanism potentially involving miR-28-5p.


Assuntos
Curcumina , Linfoma Difuso de Grandes Células B , MicroRNAs , Apoptose , Linhagem Celular Tumoral , Curcumina/farmacologia , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , MicroRNAs/genética
8.
Oncol Lett ; 16(1): 55-58, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29928386

RESUMO

The aim of the study was to investigate possible effects of p57 on the growth of the human MCF-7 and rat SHZ-88 breast cancer cell lines. Specific oligonucleotide sequences containing small hairpin structure were inserted into a small interfering RNA (siRNA) expression vector. The human MCF-7 and rat SHZ-88 breast cancer cell lines were transfected with recombinant plasmids. The p57 gene expression was blocked in the human MCF-7 breast and rat SHZ-88 breast cancer cells, using chemically modified siRNA. The p57 expression level was evaluated using quantitative polymerase chain reaction (qPCR) and western blot analysis. Immunofluorescence was conducted to detect p57 expression in the breast cancer cells. Tetrazolium blue (MTT) method was employed to detect the effect of p57 inhibition on the proliferation of the MCF-7 and SHZ-88 cell lines. Cell proliferation in the experimental group was significantly reduced. Immunofluorescence assay results showed p57 siRNA effectively inhibited the p57 level in the MCF-7 and SHZ-88 cells. RT-PCR results showed that 48 h after transfection, the p57 mRNA level in the transfected group was significantly lower compared with the control group. In conclusion, p57 effectively inhibited the proliferation of breast cancer after stable interference.

9.
Oncol Lett ; 15(5): 7076-7082, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29725431

RESUMO

microRNAs (miRNAs) perform various oncogenic or tumor suppressor functions in carcinogenesis. Currently, the underlying mechanisms of miRNAs in osteosarcoma (OS) are poorly understood. In the present study, it is demonstrated that expression of miR-544 was markedly upregulated in OS cells and clinical tissues. Furthermore, overexpression of miR-544 enhanced OS cell proliferation in vitro. Bioinformatics analysis indicated that miR-544 may target the 3'-untranslated region of axis formation inhibitor 2, which was validated using luciferase reporter gene assays. The present study demonstrated a vital role for miR-544 in promoting OS cell proliferation, indicating that it may represent a novel prognostic factor or therapeutic target for OS.

10.
Nutr J ; 15(1): 48, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27142520

RESUMO

BACKGROUND: The association between serum selenium levels and type 2 diabetes mellitus (T2DM) is controversial. We performed a systematic review and non-linear dose-response meta-analysis of observational studies to investigate the association in the present study. METHODS: A comprehensive literature search was conducted using MEDLINE and EMBASE databases. A pooled odds ratio (OR) and related 95 % confidence interval (95 % CI) for T2DM between the highest and lowest serum selenium categories, and a non-linear dose-response relationship between selenium and T2DM were estimated. RESULTS: A total of five studies (of 13,460 participants) were identified as meeting the inclusion criteria. The pooled OR indicated that there was a significantly higher prevalence of T2DM in the highest category of blood selenium compared with the lowest (OR = 1.63, 95 % CI: 1.04-2.56, P = 0.033). Moreover, a significant non-linear dose-response relationship was observed between serum selenium levels and T2DM (P < 0.001). Serum selenium levels were positively associated with T2DM in populations with relatively low serum selenium levels (<97.5 µg/l) and those with high serum selenium levels (>132.5 µg/l). CONCLUSIONS: The positive association between serum selenium levels and T2DM existed in populations with relatively low levels and high levels of serum selenium, indicating a likely U-shaped non-linear dose-response relationship between serum selenium and T2DM.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Selênio/sangue , Idoso , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , MEDLINE , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
11.
PLoS One ; 10(12): e0144785, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26658579

RESUMO

BACKGROUND: Patients' satisfaction has been considered as a crucial measurement of health care quality. Our objective was to develop a reliable and practical questionnaire for the assessment of in-patients' satisfaction in Chinese people, and report the current situation of in-patients' satisfaction in the central south area of China through a large-scale cross-sectional study. DESIGN: In order to generate the questionnaire, we reviewed previous studies, interviewed related people, held discussions, refined questionnaire items after the pilot study, and finally conducted a large cross-sectional survey to test the questionnaire. SETTING: This study was conducted in three A-level hospitals in the Hunan province, China. RESULTS: There were 6640 patients in this large-scale survey (another 695 patients in the pilot study). A factor analysis on the data from the pilot study generated four dimensions, namely, doctors' care quality, nurses' care quality, quality of the environment and facilities, and comprehensive quality. The Cronbach's alpha coefficients for each dimension were above 0.7 and the inter-subscale correlation was between 0.72 and 0.83. The overall in-patient satisfaction rate was 89.6%. CONCLUSION: The in-patient satisfaction questionnaire was proved to have optimal internal consistency, reliability, and validity.


Assuntos
Competência Clínica , Conhecimentos, Atitudes e Prática em Saúde , Satisfação do Paciente/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos , Adulto , China , Estudos Transversais , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Padrões de Prática em Enfermagem/ética , Padrões de Prática Médica/ética , Inquéritos e Questionários
12.
Mol Med Rep ; 7(2): 679-83, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23229157

RESUMO

The aim of the present study was to observe the effects of gene­activated matrix (GAM) on autograft healing of the anterior cruciate ligament. Forty­eight rabbits were randomly divided into groups A and B. Rabbits were used to construct models of anterior cruciate ligament reconstruction. In group A, transforming growth factor (TGF)­ß1 was locally injected into the bone tunnel, while in group B, empty vector was administered. Tendons were removed to observe histology and ultrastructure and to evaluate biomechanics at postoperative months 1, 3 and 6. Optical microscopy revealed increased numbers of fibroblasts and collagen fibers in group A at each time­point compared with B. Electron microscopy identified increased mitosis and abundance of fibroblasts, endoplasmic reticulum and mitochondria in group A at each time­point compared with B. No significant difference was identified in the biomechanical parameters between the 2 groups at postoperative month 1. At postoperative months 3 and 6, maximum force and elastic modulus were greater in group A compared with group B (P<0.0.5). No significant differences in other biochemical parameters were observed at these time­points. The healing ligament graft transfected with TGF­ß1 by GAM was observed to have improved tissue structure and biomechanical characteristics. The results of the current study may provide a theoretical basis for GAM application in ligament repair.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Tendões/cirurgia , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Feminino , Fibroblastos/patologia , Masculino , Microscopia Eletrônica , Coelhos , Tendões/patologia , Tendões/ultraestrutura , Fator de Crescimento Transformador beta1/farmacologia , Transplante Autólogo , Cicatrização/efeitos dos fármacos
14.
Zhongguo Zhong Yao Za Zhi ; 30(17): 1338-40, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16323542

RESUMO

OBJECTIVE: To study the polysaccharide of Condonopsis pilosula. METHOD: The polysaccharide, CPP-1, was purified by DE-52 cellulose and Sephadex G-200 gel column chromatography. Purity and molecular weight of the polysaccharide were determined by gel permeation chromatography. Methylation analysis, periodate oxidation and degradation, IR, 1H-NMR and 13C-NMR methods were adopted to elucidate the chemical structure. RESULT: The molecular weight of CPP-1 was estimated to be 7.5 x 10(4), and the structure of CPP-1 was a beta-(2 --> 1) linked beta-D-fructosan. CONCLUSION: CPP-1 was a neutral homosaccharide.


Assuntos
Codonopsis/química , Frutanos/química , Medicamentos de Ervas Chinesas/química
15.
Yao Xue Xue Bao ; 38(3): 199-202, 2003 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12830716

RESUMO

AIM: To study the chemical constituents of the pine needles from Pinus massoniana Lamb.. METHODS: Various chromatographic techniques were used for the separation and purification. The physicochemical properties and spectral data were used to elucidate the structures. RESULTS: Three compounds were isolated from the n-BuOH fraction of water-extracts. The structures were identified as (7S,8R)-4,9'-dihydroxyl-3, 3'-dimethyoxyl-7, 8-dihydrobenzofunan-1'-propanolneolignan-9-O-alpha- L-rhamnopyranoside (massonianoside D, 7), 4,4',9,9'-tetrahydroxyl-3,3'-dimethyoxyl-tetrahydrocyclolignan ((+)-isolariciresinol, 8) and 4,4',9'-trihydroxyl-3,3'-dimethyoxyl-tetrahydrocyclolignan-9-O-beta-D- xylopyranoside (isolariciresinol-9-O-xyloside, 9) on the basis of spectral data (ORD, UV, IR, MS, 1HNMR, 13CNMR, 1H-1HCOSY, HMQC and HMBC etc.). CONCLUSION: Compound 7 is a new compound, while compounds 8 and 9 were isolated from this plant for the first time.


Assuntos
Lignanas/isolamento & purificação , Monossacarídeos/isolamento & purificação , Pinus/química , Plantas Medicinais/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Lignanas/química , Lignanas/classificação , Lignina/química , Lignina/isolamento & purificação , Estrutura Molecular , Monossacarídeos/química , Naftóis/química , Naftóis/isolamento & purificação , Folhas de Planta/química
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