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1.
J Ethnopharmacol ; 264: 113021, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32479885

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Liver fibrosis is an outcome of many chronic liver diseases and often results in cirrhosis, liver failure, and even hepatocarcinoma. Xiaoyaosan decoction (XYS) as a classical Traditional Chinese Medicine (TCM) formula is used to liver fibrosis in clinical practice while its mechanism is unclear. AIM OF THE STUDY: The aim of this study was to investigate the anti-fibrosis effect of XYS and to explore the molecular mechanisms by combining network pharmacology and transcriptomic technologies. MATERIALS AND METHODS: The carbon tetrachloride (CCl4)-induced liver fibrosis rat were treated with three doses of XYS. The liver fibrosis and function were evaluated by histopathological examination and serum biochemical detection. The fibrosis related protein a-SMA and collagen I were assessed by Western blot. Different expressed genes (DEGs) between XYS-treated group and model group were analyzed. The herb-component-target network was constructed combined the network pharmacology. The predict targets and pathways were validated by in vitro and in vivo experiments. RESULTS: With XYS treatment, the liver function was significantly improved, and fibrotic changes were alleviated. The a-SMA and collagen I expression levels in the liver were also decreased in XYS-treated rats compared with CCl4 model rats. 108 active components and 42 targets from 8 herbs constituted herb-compound-target network by transcriptomics and network pharmacology analysis. The KEGG pathway and GO enrichment analyses showed that the FoxO, TGFß, AMPK, MAPK, PPAR, and hepatitis B and C pathways were involved in the anti-fibrosis effects of XYS. In the liver tissues, p-FoxO3a and p-Akt expression levels were significantly increased in the CCl4 model group but decreased in the XYS-treated group. The TGFß1/Smad pathway and Akt/FoxO3 pathway were verified in LX2 cells by inhibiting phosphorylation of Smad3 and Akt activity, respectively. CONCLUSIONS: Our findings suggested that XYS markedly alleviated CCl4-induced liver fibrosis in histopathological and serum liver function analyses, and this effect may occur via the TGFß1/Smad and Akt/FoxO signaling pathways.

2.
Chemistry ; 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32614093

RESUMO

Over the past decades, organometallic complexes with precious elements, such as ruthenium and iridium, are widely used as visible-light photoredox catalysts. Recently, more and more complexes based on earth-abundant and inexpensive elements have been used as sensitizers in photochemistry. Although the photoexcited state lifetimes of iron complexes are typically shorter than those of traditional photosensitizers, the utilization of iron catalysts in photochemistry has sprung up owing to their abundance, low price, nontoxicity, and novel properties, including exhibiting ligand to metal charge transfer states. This concept focuses on recent advances in light-driven iron catalysis in organic transformations, including iron/photoredox dual catalysis, light-induced iron photoredox catalysis and light-induced generation of active iron catalysts. The prospect for the future of this field is also discussed.

3.
Fertil Steril ; 114(2): 301-310, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32624215

RESUMO

OBJECTIVE: To evaluate a novel micro-straw as an efficient, simple method for freezing a small number of human spermatozoa for intracytoplasmic sperm injection (ICSI). DESIGN: Prospective cohort study. SETTING: Sperm bank. PATIENT(S): Men with severe oligozoospermia or azoospermia undergoing a total of 143 ICSI cycles at the CITIC-Xiangya Hospital of Reproduction and Genetics from June 1, 2015, to June 31, 2019, and 20 donors at the Hunan Province Human Sperm Bank from 2001 to 2016. INTERVENTION(S): Analysis of sperm samples and clinical outcomes after sperm use. MAIN OUTCOME MEASURE(S): Clinical information, including number of motile sperm before and after freezing, freeze-thaw survival rates, two-pronuclear fertilization rates, clinical pregnancy, and early pregnancy loss rates after sperm use. RESULT(S): In the feasibility experiment using the micro-straw, we found a freeze-thaw survival rate of 73% ± 8.3% and no difference in normal sperm morphology, normal acrosome integrity, or DNA fragmentation index between the micro-straw and 1.8-mL cryotubes. The prospective cohort included 1,325 cases, and we collected sperm from testicular, epididymis, and ejaculation sources. We observed motile sperm in 1,294 (97.6%) of 1,325 frozen-thawed samples. Postthaw sperm were available for ICSI in 140 (97.9%) of 143 of cycles. The fertilization, cleavage, and high-quality embryo rates were 1,007 (81.7%) of 1,233; 995 (98.8%) of 1,007; and 537 (53.9%) of 995, respectively. Sixty-nine (49%) clinical pregnancies were achieved, and the miscarriage rate was 6 (8.6%) of 69. CONCLUSION(S): The micro-straw is suitable and clinically useful for the cryopreservation of small numbers of spermatozoa.

4.
World J Gastroenterol ; 26(18): 2155-2165, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32476782

RESUMO

Nonalcoholic steatohepatitis (NASH) is the progressive subtype of non-alcoholic fatty liver disease and potentiates risks for both hepatic and metabolic diseases. Although the pathophysiology of NASH is not completely understood, recent studies have revealed that macrophage activation is a major contributing factor for the disease progression. Macrophages integrate the immune response and metabolic process and have become promising targets for NASH therapy. Natural products are potential candidates for NASH treatment and have multifactorial underlying mechanisms. Macrophage involvement in the development of steatosis and inflammation in NASH has been widely investigated. In this review, we assess the evidence for natural products or their active ingredients in the modulation of macrophage activation, recruitment, and polarization, as well as the metabolic status of macrophages. Our work may highlight the possible natural products that target macrophages as potential treatment options for NASH.

6.
J Environ Manage ; 254: 109810, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31698300

RESUMO

In order to predict the effects of climate change on the global carbon cycle, it is crucial to understand the environmental factors that affect soil carbon storage in grasslands. In the present study, we attempted to explain the relationships between the distribution of soil carbon storage with climate, soil types, soil properties and topographical factors across different types of grasslands with different grazing regimes. We measured soil organic carbon in 92 locations at different soil depth increments, from 0 to 100 cm in southwestern China. Among soil types, brown earth soils (Luvisols) had the highest carbon storage with 19.5 ±â€¯2.5 kg m-2, while chernozem soils had the lowest with 6.8 ±â€¯1.2 kg m-2. Mean annual temperature and precipitation, exerted a significant, but, contrasting effects on soil carbon storage. Soil carbon storage increased as mean annual temperature decreased and as mean annual precipitation increased. Across different grassland types, the mean carbon storage for the top 100 cm varied from 7.6 ±â€¯1.3 kg m-2 for temperate desert to 17.3 ±â€¯2.9 kg m-2 for alpine meadow. Grazing/cutting regimes significantly affected soil carbon storage with lowest value (7.9 ±â€¯1.5 kg m-2) recorded for cutting grass, while seasonal (11.4 ±â€¯1.3 kg m-2) and year-long (12.2 ±â€¯1.9 kg m-2) grazing increased carbon storage. The highest carbon storage was found in the completely ungrazed areas (16.7 ±â€¯2.9 kg m-2). Climatic factors, along with soil types and topographical factors, controlled soil carbon density along a soil depth in grasslands. Environmental factors alone explained about 60% of the total variation in soil carbon storage. The actual depth-wise distribution of soil carbon contents was significantly influenced by the grazing intensity and topographical factors. Overall, policy-makers should focus on reducing the grazing intensity and land conversion for the sustainable management of grasslands and C sequestration.


Assuntos
Carbono , Solo , Ciclo do Carbono , China , Pradaria , Poaceae
7.
Ann Transl Med ; 7(20): 587, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31807568

RESUMO

Background: Chronic fatigue syndrome (CFS), which is characterized by severe and disabling fatigue, has become an extensively concerned medical disorder in clinical practice. Due to the unclear etiology, current treatments are symptomatic or need assistance from psychology and kinesiology. Under the immature conditions in China, many patients would seek help from traditional Chinese medicine (TCM), in which Chinese herbal medicine (CHM) is one of the main interventions. Sijunzi Decoction (SJZD) is a classical formula and has been utilized in improving fatigue symptoms for a long time. However, lack of rigorously-designed randomized controlled trial limits its application and generalization in CFS management. Hence, we design this clinical trial to assess the effectiveness and safety of SJZD for CFS. Methods: This is a single-center, randomized, double-blind, placebo-controlled trial. Two hundred and twelve patients with CFS will be recruited from public and equally allocated to SJZD group and placebo group. Based on the general education, these two groups will receive corresponding drugs twice a day for consecutive 2 months. The follow-up period will be 1 month. The primary outcome will be the change of Chalder fatigue scoring after treatment. Secondary outcomes include the short form-36 physical function subscale (SF36-PF), spleen deficiency rating scale, quality of life and self-rated clinical global impression (CGI) scales. Discussion: The four ingredients of SJZD are Renshen (Radix Ginseng), Baizhu (Rhizoma Atractylodis Macrocephalae), Fulin (Poria) and Zhigancao (Radix Glycyrrhizae Preparata), which show potential to alleviate CFS on the foundation of available studies. The results of this trial will provide high-quality clinical evidence for the application of SJZD, and hope to further support a new TCM choice in CFS treatment. Trial registration: ISRCTN23930966 (ISRCTN registry, registered on 28th May, 2019).

8.
J Food Biochem ; 43(12): e13061, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31612542

RESUMO

The capsaicin in hot peppers is an important biological active substance that is widely used in food and medicine. In this work, six capsaicin derivatives such as N-(4-Hydroxy-3-acetophenone benzyl)acrylamide (A), 2-hydroxy-3-(octyloxy)phenyl-5-acrylamidemethylbenzene phenyl methanone (B), N-(2,5-dihydroxybenzene)acetamide (C), N-(5-acetamidemethyl benzene-2,4-dihydroxybenzene)acetamide (D), 4-acetamideme thylbenzene-2-benzylphenol (E), and N-(2-methyl-4-hydroxy-5-methylthiobenzene)acetamide (F) were synthesized via the Friedel-Crafts (F-C) alkylation reaction and were characterized using IR, 1 H NMR, and HRMS. The antioxidant activity of compounds was evaluated using the reducing power and DPPH radical (DPPH·) scavenging assays, and Vitamin C (Vc) was used as a control. The antibacterial activity was tested using minimum inhibition concentration (MIC) and antibacterial rate assays, and Escherichia coli and Staphylococcus aureus were used as the tested strain. The results showed that all six capsaicin derivatives had certain antioxidant and antibacterial activities, and the activities increased with increasing mass concentration. The best properties were obtained for compounds C and F; the antioxidant activity of compound C was similar to Vc and the MIC of compound F was 0.0313 mg/ml, its antibacterial rate was greater than 99% at 3 mg/ml. PRACTICAL APPLICATIONS: As a vegetable, peppers can be eaten fresh or processed to other forms such as pepper powder or pepper jam, and it is very popular because of its long history, unique flavor, and special functions. Our current study shows that capsaicin derivatives have good antioxidant and antibacterial activities, and therefore, the present study of capsaicin derivatives with good activity provides a good foundation for future applications in natural food additives and medicine.

9.
Biopreserv Biobank ; 17(1): 58-63, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30457887

RESUMO

BACKGROUND: Molecular research is increasingly dependent on high-quality biobanked biospecimens. Preanalytical variables in tissue processing and preservation may influence the RNA quality and research results. Hence, the effect of long-term storage and clinicopathological parameters on RNA quality needs to be elucidated. METHODS: Ninety gastric cancer tissue samples were collected and fresh-frozen in a -80°C freezer for 12 years (2006-2017). The histology was assessed and RNA integrity number (RIN) was detected by an Agilent 2100 Bioanalyzer. The impact of storage duration on RNA integrity and histomorphology was analyzed. The difference between RIN values and clinical variables was analyzed. Correlations between pathological parameters such as tumor cell percentage, stroma percentage, necrosis extent, cellularity, and RIN were assessed, respectively. RESULTS: Long-term storage at -80°C for 12 years did not adversely affect RNA integrity and histomorphology. RNA integrity was also not influenced by tumor location, estimated blood loss, cold/warm ischemia time, and surgical approach. However, RIN values were significantly correlated with the tumor cell percentage and stroma percentage. Gastric cancer tissues with higher tumor cell percentage or lower stroma percentage had higher RIN values. CONCLUSIONS: RNA quality of fresh-frozen gastric cancer tissues is influenced by clinical and histological parameters. Standard tissue collection procedure and histological quality control remain essential for tissue biobanking.


Assuntos
Isquemia Fria/efeitos adversos , RNA Neoplásico/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Idoso , Bancos de Espécimes Biológicos , Feminino , Humanos , Masculino , Controle de Qualidade , Estabilidade de RNA/genética , Manejo de Espécimes/efeitos adversos , Fatores de Tempo , Bancos de Tecidos
10.
J Am Chem Soc ; 140(50): 17338-17342, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30518213

RESUMO

Cross-electrophile couplings between two electrophiles are powerful and economic methods to generate C-C bonds in the presence of stoichiometric external reductants. Herein, we report a novel strategy to realize the first external-reductant-free cross-electrophile coupling via visible-light photoredox catalysis. A variety of tetraalkyl ammonium salts, bearing primary, secondary, and tertiary C-N bonds, undergo selective couplings with aldehydes/ketone and CO2. Notably, the in situ generated byproduct, trimethylamine, is efficiently utilized as the electron donor. Moreover, this protocol exhibits mild reaction conditions, low catalyst loading, broad substrate scope, good functional group tolerance, and facile scalability. Mechanistic studies indicate that benzyl radicals and anions might be generated as the key intermediates via photocatalysis, providing a new direction for cross-electrophile couplings.

11.
Front Oncol ; 8: 361, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30234020

RESUMO

The ectopic HLA-G expression in malignancies has been extensively explored and clinical significance of the molecule was widely acknowledged. Besides previously well-documented seven isoforms (HLA-G1~-G7), other novel isoforms of HLA-G have been reported but their clinical relavenace remians evaluated. In this study, lesion HLA-G expression in 379 case-matched serial section primary colorectal cancers (CRC) were evaluated with mAb 4H84 (recognizing an epitope in HLA-G α1 domain), and mAb 5A6G7 (recognizing an epitope encoded by intron 4), respectively. Data showed that HLA-G positive staining with mAbs 4H84 and 5A6G7 was 70.7 and 60.4%, respectively. When percentage of HLA-G expression detected with mAb 4H84 subtracted that with mAb 5A6G7, the difference (ΔHLA-G) with negative (ΔHLA-Gneg), comparable (ΔHLA-Gcom) and positive (ΔHLA-Gpos) were observed in 64 (16.9%), 159 (42.0%), and 156 (41.2%) cases, respectively. Noteworthy, unexpected immunostaining was observed in 44 (11.6%) lesions that no staining was detected with mAb 4H84 but positive with mAb 5A6G7 (4H84neg5A6G7pos). This staining pattern was unpredictable because all seven known HLA-G isoforms containing the α 1 domain could be recognized by the mAb 4H84. Moreover, patients with ΔHLA-Gneg had obviously better survival than those with ΔHLA-Gcom and ΔHLA-Gpos (p = 0.017), and ΔHLA-G could be an independent prognostic factor for CRC patients (p = 0.008). Our findings provides the first report that potential unidentified HLA-G isoforms is of distinct clinical significance in CRC patients.

12.
Chem Commun (Camb) ; 54(44): 5610-5613, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29770416

RESUMO

A direct and practical synthesis of important tetronic acids from easily available propargylic alcohols and carbon dioxide is reported for the first time. This transition-metal-free transformation features high atom- and step-economy, mild reaction conditions, good functional group tolerance and high yield. Preliminary mechanistic studies suggest that the reaction proceeds via cyclization to give alkylidene cyclic carbonate, ring-opening and re-cyclization processes.

13.
Org Lett ; 20(10): 3049-3052, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29717611

RESUMO

A selective oxy-alkylation of allylamines with unactivated alkyl bromides and CO2 via visible-light-driven palladium catalysis is reported. The commercially available Pd(PPh3)4 is used as the sole catalyst in this three-component reaction. A variety of tertiary, secondary, and primary alkyl bromides undergo reactions to generate important 2-oxazolidinones in high yields and selectivity. The mild reaction conditions, easy scalability, and facile derivatization of products provide great potential for application in organic synthesis and pharmaceutical chemistry.

14.
Chin Med ; 13: 65, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619503

RESUMO

Systems biology is an academic field that attempts to integrate different levels of information to understand how biological systems function. It is the study of the composition of all components of a biological system and their interactions under specific conditions. The core of systems biology is holistic and systematic research, which is different from the manner of thinking and research of all other branches of biology to date. Chinese herbal formulae (CHF) are the main form of Chinese medicine and are composed of single Chinese herbal medicines (CHMs) with pharmacological and pharmacodynamic compatibility. When single CHMs are combined into CHF, the result is different from the original effect of a single drug and can be better adapted to more diseases with complex symptoms. CHF represent a complex system with multiple components, targets and effects. Therefore, the use of systems biology is conducive to revealing the complex characteristics of CHF. With the rapid development of omics technologies, systems biology has been widely and increasingly applied to the study of the basis of the pharmacological substances, action targets and mechanisms of CHF. To meet the challenges of multiomics synthesis-intensive studies and system dynamics research in CHF, this paper reviews the common techniques of genomics, transcriptomics, proteomics, metabolomics, and metagenomics and their applications in research on CHF.

15.
Org Lett ; 20(1): 190-193, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29280636

RESUMO

A selective oxy-difluoroalkylation of allylamines with carbon dioxide (CO2) via visible-light photoredox catalysis is reported. These multicomponent reactions are efficient and environmentally friendly to generate a series of important 2-oxazolidinones with functionalized difluoroalkyl groups. The good functional group tolerance, broad substrate scope, easy scalability, mild reaction conditions, and facile functionalization of products provide great potential for application in organic synthesis and pharmaceutical chemistry.

16.
Angew Chem Int Ed Engl ; 56(48): 15416-15420, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-29024349

RESUMO

The first thiocarboxylation of styrenes and acrylates with CO2 was realized by using visible light as a driving force and catalytic iron salts as promoters. A variety of important ß-thioacids were obtained in high yields. This multicomponent reaction proceeds in an atom- and redox-economical manner with broad substrate scope under mild reaction conditions. Notably, high regio-, chemo-, and diasteroselectivity are observed. Mechanistic studies indicate that a radical pathway can account for the unusual regioselectivity.

17.
Angew Chem Int Ed Engl ; 56(49): 15683-15687, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29048716

RESUMO

Reported herein is a novel visible-light photoredox system with Pd(PPh3 )4 as the sole catalyst for the realization of the first direct cross-coupling of C(sp3 )-H bonds in N-aryl tetrahydroisoquinolines with unactivated alkyl bromides. Moreover, intra- and intermolecular alkylations of heteroarenes were also developed under mild reaction conditions. A variety of tertiary, secondary, and primary alkyl bromides undergo reaction to generate C(sp3 )-C(sp3 ) and C(sp2 )-C(sp3 ) bonds in moderate to excellent yields. These redox-neutral reactions feature broad substrate scope (>60 examples), good functional-group tolerance, and facile generation of quaternary centers. Mechanistic studies indicate that the simple palladium complex acts as the visible-light photocatalyst and radicals are involved in the process.

18.
Int J Biometeorol ; 61(10): 1885-1892, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28761981

RESUMO

Canopy temperature is a result of the canopy energy balance and is driven by climate conditions, plant architecture, and plant-controlled transpiration. Here, we evaluated canopy temperature in a rubber plantation (RP) and tropical rainforest (TR) in Xishuangbanna, southwestern China. An infrared temperature sensor was installed at each site to measure canopy temperature. In the dry season, the maximum differences (Tc - Ta) between canopy temperature (Tc) and air temperature (Ta) in the RP and TR were 2.6 and 0.1 K, respectively. In the rainy season, the maximum (Tc - Ta) values in the RP and TR were 1.0 and -1.1 K, respectively. There were consistent differences between the two forests, with the RP having higher (Tc - Ta) than the TR throughout the entire year. Infrared measurements of Tc can be used to calculate canopy stomatal conductance in both forests. The difference in (Tc - Ta) at three gc levels with increasing direct radiation in the RP was larger than in the TR, indicating that change in (Tc - Ta) in the RP was relatively sensitive to the degree of stomatal closure.


Assuntos
Hevea , Floresta Úmida , Temperatura , Mudança Climática , Hevea/fisiologia , Raios Infravermelhos , Folhas de Planta/fisiologia , Transpiração Vegetal , Estações do Ano , Árvores/fisiologia , Clima Tropical
19.
Org Lett ; 19(14): 3735-3738, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28686460

RESUMO

A phosphorylation of alkenyl and aryl C-O bonds at room temperature via photoredox/nickel dual catalysis is reported. By starting from easily available and inexpensive sulfonates, a variety of important alkenyl phosphonates and aryl phosphine oxides are generated in moderate to excellent yields. This method features mild reaction conditions, high selectivity, good functional group tolerance, wide substrate scope, and easy scalability.

20.
ChemSusChem ; 10(7): 1337-1340, 2017 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28256071

RESUMO

From ugly duckling to beautiful C1: Although CO2 may represent an ideal C1 source, it is challenging to use it as a raw material and direct carboxylation with CO2 has mainly been confined to highly reactive species. However, recent significant breakthroughs have been made in photochemical carboxylation of challenging, un-acidic, C(sp3 )-H bonds, including benzylic, allylic and amine C-H bonds.


Assuntos
Dióxido de Carbono/química , Carbono/química , Ácidos Carboxílicos/química , Hidrogênio/química , Processos Fotoquímicos , Catálise
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