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1.
J Org Chem ; 85(15): 9454-9463, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32687362

RESUMO

Asymmetric construction of α-carbolinones with easily available starting materials has recently attracted considerable attention from the synthesis community, and the development of effective catalysis for this target is in great demand. Here, a bifunctional Brønsted base catalyzed asymmetric [3 + 3] cyclization of indolin-2-imines and α,ß-unsaturated N-acylated succinimides was developed by using the strategy of noncovalent bonding catalysis. With this organocatalytic protocol, a variety of tetrahydro-α-carbolinones bearing different substituents were synthesized with up to 99% yield and up to 96:4 er.

2.
J Exp Biol ; 221(Pt 19)2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30135088

RESUMO

RNA interference (RNAi) is a post-transcriptional gene silencing mechanism triggered by double-stranded RNA (dsRNA) that is homologous in sequence to the silenced gene and is conserved in a wide range of eukaryotic organisms. The RNAi mechanism has provided unique opportunities for combating honey bee diseases caused by various parasites and pathogens. Nosema ceranae is a microsporidian parasite of European honey bees, Apis mellifera, and has been associated with honey bee colony losses in some regions of the world. Here we explored the possibility of silencing the expression of a N. ceranae putative virulence factor encoding polar tube protein 3 (ptp3) which is involved in host cell invasion as a therapeutic strategy for controlling Nosema parasites in honey bees. Our studies showed that the oral ingestion of a dsRNA corresponding to the sequences of N. ceranae ptp3 could effectively suppress the expression of the ptp3 gene in N. ceranae-infected bees and reduce Nosema load. In addition to the knockdown of ptp3 gene expression, ingestion of ptp3-dsRNA also led to improved innate immunity in bees infected with N. ceranae along with an improvement in physiological performance and lifespan compared with untreated control bees. These results strongly suggest that RNAi-based therapeutics hold real promise for the effective treatment of honey bee diseases in the future, and warrant further investigation.


Assuntos
Abelhas/imunologia , Nosema/fisiologia , Proteínas de Protozoários/genética , Interferência de RNA , Animais , Criação de Abelhas , Abelhas/parasitologia , Imunidade Inata , Nosema/genética , Proteínas de Protozoários/metabolismo , RNA de Cadeia Dupla/administração & dosagem
3.
Chem Biol Drug Des ; 103(2): e14489, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38404216

RESUMO

Rapid restoration of perfusion in ischemic myocardium is the most direct and effective treatment for coronary heart disease but may cause myocardial ischemia/reperfusion injury (MIRI). Cinnamaldehyde (CA, C9H8O), a key component in the well-known Chinese medicine cinnamomum cassia, has cardioprotective effects against MIRI. This study aimed to observe the therapeutic effect of CA on MIRI and to elucidate its potential mechanism. H9C2 rat cardiomyocytes were pretreated with CA solution at 0, 10, and 100 µM, respectively and subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). Then the cell viability, the NF-κB and caspase3 gene levels, the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio, superoxide dismutase (SOD) level, reactive oxygen species (ROS) generation, 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA) were detected. The severity of DNA damage was assessed by tail moment (TM) values using alkaline comet assay. Besides, the DNA damage-related proteins and the key proteins of the Nrf2 pathway were detected by western blot. CA treatment increased the cell viability, GHS/GSSG ratio, SOD level, PARP1, Nrf2, PPAR-γ, and HO-1 protein levels of H9C2 cardiomyocytes, while reducing NF-κB, caspase3, ROS level, 4-HNE and MDA content, γ-H2AX protein level, and TM values. Inhibition of the Nrf2 pathway reversed the effect of CA on cell viability and apoptosis of OGD/R induced H9C2 cardiomyocytes. Besides, 100 µM CA was more effective than 10 µM CA. In the OGD/R-induced H9C2 cardiomyocyte model, CA can protect cardiomyocytes from MIRI by attenuating lipid peroxidation and repairing DNA damage. The mechanism may be related to the activation of the Nrf2 pathway.


Assuntos
Acroleína , Miócitos Cardíacos , Fator 2 Relacionado a NF-E2 , Oxigênio , Animais , Ratos , Acroleína/análogos & derivados , Acroleína/farmacologia , Apoptose , Dano ao DNA , Glucose/farmacologia , Dissulfeto de Glutationa/genética , Dissulfeto de Glutationa/metabolismo , Dissulfeto de Glutationa/farmacologia , Peroxidação de Lipídeos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Oxigênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
4.
Int Breastfeed J ; 19(1): 22, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570781

RESUMO

BACKGROUND: Healthcare providers play important roles in supporting breastfeeding. Although there has been insufficient actual breastfeeding support from healthcare providers in China, little research has been conducted to understand Chinese healthcare providers' perceived barriers to providing breastfeeding support, especially in rural China. This study aims to identify these perceived barriers to providing breastfeeding support in Northwestern rural China. METHODS: This study was conducted during the period from March 2018 to December 2018. Forty-one healthcare providers were recruited through purposive sampling in two rural counties in Northwest China that are in close proximity to each other and share similar demographic features. Participants included obstetrician-gynecologists, midwives, nurses, "village doctors", and township and village maternal and child health workers. Qualitative data were collected through one-on-one in-depth semi-structured interviews and focus group discussions. Transcripts were thematically analyzed. RESULTS: Analysis of interview data resulted in four themes that the participants perceived as barriers to supporting breastfeeding: (1) lack of medical resources, within which inadequate staffing, and lack of financial incentives were discussed, (2) lack of clear and specific responsibility assignment, within which no one takes the lead, and mutual buck-passing were discussed, (3) healthcare providers' lack of relevant expertise, within which lack of knowledge and skills, and low prestige of village healthcare providers were discussed, (4) difficulties in accessing mothers, within which medical equipment shortages reduce services utilization, mothers' housing situation, mothers' mobility, and cultural barriers were discussed. CONCLUSIONS: The study identified HCPs perceived barriers to providing breastfeeding support. Unique to China's Tri-Level Healthcare System, challenges like staffing and financial incentives are hard to swiftly tackle. Recommendations include mHealth enhancement and clarified responsibilities with incentives and tailored training. Further research is crucial to evaluate these strategies in rural Northwestern China and comparable underdeveloped areas nationwide.


Assuntos
Aleitamento Materno , Pessoal de Saúde , Gravidez , Feminino , Criança , Humanos , Pesquisa Qualitativa , Mães , China
5.
World J Gastroenterol ; 29(20): 3084-3102, 2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37346150

RESUMO

BACKGROUND: Capecitabine (CAP) is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation (LT) in clinical studies. Our previous study showed that metronomic CAP can cause the programmed death of T cells by inducing oxidative stress in healthy mice. Ferroptosis, a newly defined non-apoptotic cell death that occurs in response to iron overload and lethal levels of lipid peroxidation, is an important mechanism by which CAP induces cell death. Therefore, ferroptosis may also play an important role in CAP-induced T cell death and play an immunosuppressive role in acute rejection after trans-plantation. AIM: To investigate the functions and underlying mechanisms of antirejection effects of metronomic CAP. METHODS: A rat LT model of acute rejection was established, and the effect of metronomic CAP on splenic hematopoietic function and acute graft rejection was evaluated 7 d after LT. In vitro, primary CD3+ T cells were sorted from rat spleens and human peripheral blood, and co-cultured with or without 5-fluorouracil (5-FU) (active agent of CAP). The levels of ferroptosis-related proteins, ferrous ion concentration, and oxidative stress-related indicators were observed. The changes in mito-chondrial structure were observed using electron microscopy. RESULTS: With no significant myelotoxicity, metronomic CAP alleviated graft injury (Banff score 9 vs 7.333, P < 0.001), prolonged the survival time of the recipient rats (11.5 d vs 16 d, P < 0.01), and reduced the infiltration rate of CD3+ T cells in peripheral blood (6.859 vs 3.735, P < 0.001), liver graft (7.459 vs 3.432, P < 0.001), and spleen (26.92 vs 12.9, P < 0.001), thereby inhibiting acute rejection after LT. In vitro, 5-FU, an end product of CAP metabolism, induced the degradation of the ferritin heavy chain by upregulating nuclear receptor coactivator 4, which caused the accumulation of ferrous ions. It also inhibited nuclear erythroid 2 p45-related factor 2, heme oxygenase-1, and glutathione peroxidase 4, eventually leading to oxidative damage and ferroptosis of T cells. CONCLUSION: Metronomic CAP can suppress acute allograft rejection in rats by triggering CD3+ T cell ferroptosis, which makes it an effective immunosuppressive agent after LT.


Assuntos
Ferroptose , Transplante de Fígado , Ratos , Camundongos , Animais , Humanos , Capecitabina , Transplante de Fígado/efeitos adversos , Linfócitos T , Complicações Pós-Operatórias , Fluoruracila/farmacologia , Rejeição de Enxerto/prevenção & controle , Imunossupressores/farmacologia , Ferro
6.
Microorganisms ; 9(3)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673613

RESUMO

Nosema ceranae (Opisthosporidia: Microsporidia) is an emergent intracellular parasite of the European honey bee (Apis mellifera) and causes serious Nosema disease which has been associated with worldwide honey bee colony losses. The only registered treatment for Nosema disease is fumagillin-b, and this has raised concerns about resistance and off-target effects. Fumagillin-B is banned from use in honey bee colonies in many countries, particularly in Europe. As a result, there is an urgent need for new and effective therapeutic options to treat Nosema disease in honey bees. An RNA interference (RNAi)-based approach can be a potent strategy for controlling diseases in honey bees. We explored the therapeutic potential of silencing the sequences of two N. ceranae encoded spore wall protein (SWP) genes by means of the RNAi-based methodology. Our study revealed that the oral ingestion of dsRNAs corresponding to SWP8 and SWP12 used separately or in combination could lead to a significant reduction in spore load, improve immunity, and extend the lifespan of N. ceranae-infected bees. The results from the work completed here enhance our understanding of honey bee host responses to microsporidia infection and highlight that RNAi-based therapeutics are a promising treatment for honey bee diseases.

7.
Insect Sci ; 28(2): 457-471, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32112590

RESUMO

Workers of Apis cerana cerana undergo an in-hive nursing to outdoor foraging transition, but the genes underlying this age-related transition remain largely unknown. Here, we sequenced the head transcriptomes of its 7-day-old normal nurses, 18- and 22-day-old normal foragers, 7-day-old precocious foragers and 22-day-old over-aged nurses to unravel the genes associated with this transition. Mapping of the sequence reads to Apis mellifera genome showed that the three types of foragers had a greater percentage of reads from annotated exons and intergenic regions, whereas the two types of nurses had a greater percentage of reads from introns. Pair- and group-wise comparisons of the five transcriptomes revealed 59 uniquely expressed genes (18 in nurses and 41 in foragers) and 14 nurse- and 15 forager-upregulated genes. The uniquely expressed genes are usually low-abundance long noncoding RNAs, transcription factors, transcription coactivators, RNA-binding proteins, kinases or phosphatases that are involved in signaling and/or regulation, whereas the nurse- or forager-upregulated genes are often high-abundance downstream genes that directly perform the tasks of nurses or foragers. Taken together, these results suggest that the nurse-forager transition is coordinated by a social signal-triggered epigenetic shift from introns to exons/intergenic regions and the resulting transcriptional shift between the nurse- and forager-associated genes.


Assuntos
Abelhas/genética , Proteínas de Insetos/genética , Características de História de Vida , Transcriptoma , Animais , Abelhas/metabolismo , Perfilação da Expressão Gênica , Proteínas de Insetos/metabolismo
8.
Chin Med J (Engl) ; 130(16): 1945-1952, 2017 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-28776547

RESUMO

BACKGROUND: Current understanding of tumor biology suggests that breast cancer is a group of diseases with different intrinsic molecular subtypes. Anatomic staging system alone is insufficient to provide future outcome information. The American Joint Committee on Cancer (AJCC) expert panel updated the 8th edition of the staging manual with prognostic stage groups by incorporating biomarkers into the anatomic stage groups. In this study, we retrospectively analyzed the data from our center in China using the anatomic and prognostic staging system based on the AJCC 8th edition staging manual. METHODS: We reviewed the data from January 2008 to December 2014 for cases with Luminal B Human Epidermal Growth Factor Receptor 2 (HER2)-negative breast cancer in our center. All cases were restaged using the AJCC 8th edition anatomic and prognostic staging system. The Kaplan-Meier method and log-rank test were used to compare the survival differences between different subgroups. SPSS software version 19.0 (IBM Corp., Armonk, NY, USA) was used for the statistical analyses. RESULTS: This study consisted of 796 patients with Luminal B HER-negative breast cancer. The 5-year disease-free survival (DFS) of 769 Stage I-III patients was 89.7%, and the 5-year overall survival (OS) of all 796 patients was 91.7%. Both 5-year DFS and 5-year OS were significantly different in the different anatomic and prognostic stage groups. There were 372 cases (46.7%) assigned to a different group. The prognostic Stage II and III patients restaged from anatomic Stage III had significant differences in 5-year DFS (χ2 = 11.319, P= 0.001) and 5-year OS (χ2 = 5.225, P= 0.022). In addition, cases restaged as prognostic Stage I, II, or III from the anatomic Stage II group had statistically significant differences in 5-year DFS (χ2 = 6.510, P= 0.039) but no significant differences in 5-year OS (χ2 = 5.087, P= 0.079). However, the restaged prognostic Stage I and II cases from anatomic Stage I had no statistically significant differences in either 5-year DFS (χ2 = 0.440, P= 0.507) or 5-year OS (χ2 = 1.530, P= 0.216). CONCLUSIONS: The prognostic staging system proposed in the AJCC 8th edition refines the anatomic stage group in Luminal B HER2-negative breast cancer and will lead to a more personalized approach to breast cancer treatment.


Assuntos
Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Neoplasias da Mama/genética , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/genética , Estudos Retrospectivos , Adulto Jovem
9.
PLoS One ; 12(11): e0187505, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29125851

RESUMO

It has become increasingly clear that gut bacteria play vital roles in the development, nutrition, immunity, and overall fitness of their eukaryotic hosts. We conducted the present study to investigate the effects of gut microbiota disruption on the honey bee's immune responses to infection by the microsporidian parasite Nosema ceranae. Newly emerged adult workers were collected and divided into four groups: Group I-no treatment; Group II-inoculated with N. ceranae, Group III-antibiotic treatment, and Group IV-antibiotic treatment after inoculation with N. ceranae. Our study showed that Nosema infection did not cause obvious disruption of the gut bacterial community as there was no significant difference in the density and composition of gut bacteria between Group I and Group II. However, the elimination of gut bacteria by antibiotic (Groups III and IV) negatively impacted the functioning of the honey bees' immune system as evidenced by the expression of genes encoding antimicrobial peptides abaecin, defensin1, and hymenoptaecin that showed the following ranking: Group I > Group II > Group III > Group IV. In addition, significantly higher Nosema levels were observed in Group IV than in Group II, suggesting that eliminating gut bacteria weakened immune function and made honey bees more susceptible to Nosema infection. Based on Group IV having displayed the highest mortality rate among the four experimental groups indicates that antibiotic treatment in combination with stress, associated with Nosema infection, significantly and negatively impacts honey bee survival. The present study adds new evidence that antibiotic treatment not only leads to the complex problem of antibiotic resistance but can impact honey bee disease resistance. Further studies aimed at specific components of the gut bacterial community will provide new insights into the roles of specific bacteria and possibly new approaches to improving bee health.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Abelhas/microbiologia , Intestinos/microbiologia , Nosema/patogenicidade , Animais , Abelhas/genética , Interações Hospedeiro-Patógeno
10.
J Chin Med Assoc ; 79(5): 281-91, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26935853

RESUMO

BACKGROUND: In March 2009, the first reported case infected with influenza A (H1N1) virus was identified in Mexico. The World Health Organization officially declared the outbreak to be a pandemic on June 11, 2009. The objective of this study was to evaluate the efficacy and safety of traditional Chinese medicine (TCM) in the treatment of influenza A (H1N1) infection. METHODS: We electronically and manually searched electronic databases, reference lists, and conference compilations to identify randomized clinical trials that compared the treatment of influenza A (H1N1) using TCM with a control group receiving oseltamivir or antivirus therapy. The Jadad score was used to assess trial quality. Duration of viral shedding, time to defervescence, and effective rate were taken as outcome measurements; additionally, heterogeneity analysis and meta-analysis were performed. RESULTS: A total of 30 studies were included in our investigation, and these studies together included 3444 cases. Based on the Jadad score, each of these studies were divided as follows: high-quality studies (n = 3), medium-quality studies (n = 2), and low quality studies (n = 25). A meta analysis was performed, which indicated that the time to defervescence between the TCM treatment group and the control group was statistically significant, the duration of viral [Influenza A (H1N1)] shedding in the integrated Chinese and Western medicine subgroups was statistically significant, but it was not statistically significant between the two groups, the effective rate between the two groups was not statistically significant. A total of 18 studies described adverse drug reactions. CONCLUSION: The results of our study indicated that the mean time to defervescence in the TCM treatment group was less than noted in the control group, and that the duration of viral [Influenza A (H1N1)] shedding in the integrated Chinese and Western medicine subgroups was less than that noted in the control group. However, the available evidence does not consider the fact that the difference in duration of viral shedding and effective rate between the two groups was statistically similar. No obvious adverse events were reported in the included studies.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/tratamento farmacológico , Medicina Tradicional Chinesa , Adulto , Feminino , Humanos , Influenza Humana/virologia , Masculino , Medicina Tradicional Chinesa/efeitos adversos , Pessoa de Meia-Idade , Eliminação de Partículas Virais
11.
Dongwuxue Yanjiu ; 31(6): 675-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21174360

RESUMO

One specimen was collected from the main course of Lancangjiang River (upper reach of Mekong) in Guanlei Port, Xishuangbanna, Yunnan, China in April, 2008. It is identified as Dasyatis laosensis, a new record of Dasyatidae species in China. It could be distinguished from other Dasyatis species by a combination of the following characteristics: one enlarged venomous spine on the tail, ventral surface of body with orange marginal coloration, tail length greater than body length.


Assuntos
Rajidae/classificação , Animais , China , Ecossistema , Rajidae/anatomia & histologia
12.
Arch Insect Biochem Physiol ; 60(1): 1-12, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16116618

RESUMO

Phospholipase A(2) (PLA(2)) is one of the components of bee venom with a wide range of pharmacological functions. It operates as a major allergen working with other venom components to defend the colony from intruder. In the present study, the cDNA sequence of the Ac-pla(2) gene from cDNA library of the venom gland of Apis cerana was compared with the amplified corresponding region of genomic DNA. The result showed that the Ac-pla(2) gene consisted of four exons and three introns. Southern blot showed that the Ac-pla(2) gene was a single copy per haploid genome. The most active transcription period was during the first 8 days of adults, which correspondingly was the period of sharp increase of PLA(2) protein. ELISA analysis revealed that the PLA(2) was undetectable in pupal stage and the newly eclosed adult, but increased sharply to a maximum of 10-12 mug per honeybee by 8-10 days of adult life, followed by a gradual decrease to 8 mug for the rest of adult life. Transcriptional or post transcriptional regulation is the key step for Ac-pla(2) expression. The early secreted Ac-PLA(2) showed a low degree of post-translational modification; with increasing age, glycosylation was detected by Western blot and glycoprotein staining analysis. Different post-translational modifications were found among different individuals in A. cerana when compared to A. mellifera.


Assuntos
Venenos de Abelha/enzimologia , Abelhas , Regulação Enzimológica da Expressão Gênica , Fosfolipases A/genética , Fosfolipases A/metabolismo , Fatores Etários , Sequência de Aminoácidos , Animais , Sequência de Bases , Venenos de Abelha/genética , Southern Blotting , Western Blotting , China , Primers do DNA , DNA Complementar/genética , Ensaio de Imunoadsorção Enzimática , Componentes do Gene , Biblioteca Gênica , Glicoproteínas/metabolismo , Dados de Sequência Molecular , Fosfolipases A2 , Análise de Sequência de DNA
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 9(3): 284-286, 2001 Sep.
Artigo em Zh | MEDLINE | ID: mdl-12578609

RESUMO

The aim of this study was to investigate the initial time of platelet inhibiting effect of aspirin (ASA) and the effects of different doses on equilibrium of prostacyclin (PGI(2))-thromboxane B(2) (TXB(2)). The effects of 100 mg and 300 mg ASA on Platelet count, platelet aggregation rate, TXB(2) and PGI(2) were investigated using cross-compare way for 40 aspirin ingestion patients. The results showed that the platelet counts decreased to 33% after 30 minutes of single-dose ASA ingestion of 100 mg and to 25.6% after 60 minutes. TXB(2) and PGI(2) also decreased meanwhile. The platelet counts decreased to 39.5%, 35.5% and 26.6%, respectively with dose of 300 mg on day 1, 2 and 3. The platelet counts decreased to 38.1% and 39.5%, respectively, after 120 minutes with 100 and 300 mg ASA ingestion, without significent difference. In conclusion ASA began to inhibit platelet function after 30 minutes of ingestion, and gave the strongest inhibition after 60 minutes. Continuous ASA ingestion accumulates the inhibitory effect. The single-dose ASA ingestion of 100 and 300 mg have nearly the same inhibitory effects.

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