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1.
Plant Cell Environ ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38516697

RESUMO

Stomatal movement is critical for water transpiration, gas exchange, and responses to biotic stresses. Abscisic acid (ABA) induces stomatal closure to prevent water loss during drought. We report that Arabidopsis CIPK8 negatively regulates ABA-mediated stomatal closure and drought tolerance. CIPK8 is highly enriched in guard cells and transcriptionally induced by ABA. Functional loss of CIPK8 results in hypersensitive stomatal closure to ABA and enhanced drought tolerance. Guard cell-specific downregulation of CIPK8 mimics the phenotype of cipk8 whereas guard cell-specific expression of a constitutive active CIPK8 (CIPK8CA) has an opposite effect, suggesting a cell autonomous activity of CIPK8. CIPK8 physically interacts with CBL1 and CBL9. Functional loss of CBL1 and CBL9 mimics ABA-hypersensitive stomatal closure of cipk8 whereas abolishes the effect of CIPK8CA, indicating that CIPK8 and CBL1/CBL9 form a genetic module in ABA-responsive stomatal movement. SlCIPK7, the functional homolog of CIPK8 in tomato (Solanum lycopersicum), plays a similar role in ABA-responsive stomatal movement. Genomic editing of SlCIPK7 results in more drought-tolerant tomato, making it a good candidate for germplasm improvement.

2.
Front Physiol ; 14: 1221898, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614760

RESUMO

Background: Exercise has emerged as an effective approach to promote individual health and has shown potential in aiding smoking cessation. However, the specific benefits of exercise in smoking cessation remain unclear, and conflicting findings across studies may be attributed to variations in study populations and intervention characteristics. This study aims to conduct a meta-analysis to evaluate the impact of exercise interventions on tobacco dependence in smokers and assess the effectiveness of exercise in facilitating smoking cessation. Methods: A comprehensive search was performed in databases including PubMed, Web of Science, Embase, The Cochrane Library, and Scopus to identify relevant randomized controlled trials published before 30 October 2022. The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines were followed during the review process. The quality of evidence (QoE) was assessed with GRADE (grading of recommendations, assessment, development and evaluations) methodology. Results: Acute exercise was found to significantly reduce smoking cravings [MD = -1.84, 95% CI (-2.92, -0.76), p < 0.001; SMD = -1.64, 95% CI (-2.22, -1.05), p < 0.001] and alleviate most withdrawal symptoms in smokers. However, there was no significant difference in the smoking cessation rate between the exercise group and the control group (p > 0.05). Exercise was associated with increased positive mood [SMD = 0.36, 95% CI (0.14, 0.58), p = 0.001] and reduced negative mood in smokers [SMD = -0.26, 95% CI (-0.39, -0.12), p < 0.001]. Conclusion: Acute exercise interventions effectively reduce cravings and withdrawal symptoms in smokers. However, long-term exercise interventions do not significantly improve the smoking cessation rate. Exercise can help reduce negative mood and enhance positive mood in smokers. Smokers with high levels of tobacco dependence may derive less benefit from exercise. Factors such as literature quality, exercise intervention characteristics, and exercise adherence may influence the effectiveness of interventions. Trial registration: This research protocol was registered in the International Prospective Register for Systematic Reviews (PROSPERO https://www.crd.york.ac.uk/PROSPERO/). Registration number: CRD42022326109.

3.
PLoS One ; 17(5): e0267831, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35639684

RESUMO

Lactobacillus plantarum (LP) has been shown to exhibit protective effects on intestinal barrier function in septic rats, although the regulatory mechanism has not been established. We determined whether LP imparts such protective effects in a lipopolysaccharide (LPS)-induced Caco2 cell monolayer model and whether cAMP-PKA signaling is the underlying mechanism of action. The cyclic adenosine monophosphate (cAMP) agonist, forskolin (FSK), and the protein kinase A (PKA) inhibitor, HT89, were used to study the protective effect of LP on the destruction of the tight junction (TJ) structure of cells treated with LPS and the corresponding changes in cAMP-PKA signaling. Our experimental results demonstrated that LP promoted the expression of TJ proteins between Caco2 cells after LPS treatment, and increased the electrical barrier detection (TEER) between Caco2 cells. Moreover, transmission electron microscopy (TEM) revealed that the TJ structural integrity of cells treated with LPS + LP was improved compared to cells treated with LPS alone. In addition, our findings were consistent between the FSK and LP intervention group, while HT89 inhibited LP influence. Taken together, our results indicate that LP has an improved protective effect on LPS-induced damage to the monolayer membrane barrier function of Caco2 cells and is regulated by the cAMP-PKA pathway.


Assuntos
Lactobacillus plantarum , Lipopolissacarídeos , Animais , Células CACO-2 , Colforsina/farmacologia , AMP Cíclico/fisiologia , Humanos , Intestinos , Lipopolissacarídeos/farmacologia , Ratos
4.
J Gastroenterol Hepatol ; 36(2): 455-466, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32667711

RESUMO

BACKGROUND AND AIM: 5-Lipoxygenase has been reported to enhance cell proliferation, migration, and invasion. Epithelial-mesenchymal transition is considered an important process for tumor metastasis and invasion. METHODS: The 5-lipoxygenase expression levels and the prognoses in patients with gastric cancer were evaluated by immunohistochemistry and by the log-rank test on Kaplan-Meier curves. We established 5-lipoxygenase-overexpressed and 5-lipoxygenase-silenced gastric cancer cells and measured migration, invasion, and epithelial-mesenchymal transition makers to examine the role of 5-lipoxygenase in gastric cancer in vitro. In vivo, 5-lipoxygenase-overexpressed gastric cancer cells were administered into mice by subcutaneous injection, intraperitoneal injection or splenic intravenous injection to study the proliferation or metastasis of 5-lipoxygenase in mice. Using the extracellular signal-regulated kinase pathway inhibitor U0126 and activator tumor growth factor-ß, we investigated the mechanism of epithelial-mesenchymal transition induced by 5-lipoxygenase in gastric cancer cells. RESULTS: 5-Lipoxygenase was upregulated in gastric cancer tissues and was related to poor overall survival in gastric cancer patients. 5-Lipoxygenase promoted gastric cancer cell proliferation, migration, and invasion and induced the process of epithelial-mesenchymal transition in gastric cancer cells. In the nude mouse model, mice with gastric cancer tumors overexpressing 5-LOX had a faster tumor growth rate and more severe abdominal and liver metastases than the control group. Inhibition of extracellular signal-regulated kinase signaling by U0126 or activation by tumor growth factor-ß neutralized the effect of 5-LOX overexpression or silencing on epithelial-mesenchymal transition. CONCLUSION: 5-Lipoxygenase promotes epithelial-mesenchymal transition in gastric cancer by activating the extracellular signal-regulated kinase signaling pathway.


Assuntos
Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/fisiologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Araquidonato 5-Lipoxigenase/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Expressão Gênica , Humanos , Camundongos , Invasividade Neoplásica/genética , Neoplasias Gástricas/metabolismo
5.
Plant Cell ; 32(12): 3812-3824, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32989172

RESUMO

Plant roots are sustained through meristem activity at the root tip. Two transcriptional pathways, one mediated by PLETHORAs (PLTs) and the other by SHORTROOT and SCARECROW, play major roles in root meristem development. The role of PLTs during root meristem development requires a concentration gradient, which is not only contributed by posttranslational regulation such as growth dilution and intercellular movement but also likely by a largely unknown fine-tuned transcriptional regulatory mechanism. We report here that Arabidopsis (Arabidopsis thaliana) JANUS positively regulates PLT1 expression in the root meristem by recruiting RNA polymerase II (Pol II) to PLT1 and by interacting with PLT1. JANUS-dependent recruitment of Pol II is inhibited through the competitive binding of JANUS by GRF-INTERACTING FACTOR1 (GIF1)/ANGUSTIFOLIA3, a transcriptional cofactor that negatively regulates PLT1 expression. Finally, GIF1 and JANUS, the antagonistic regulators of PLT1, both depend on Arabidopsis IMPORTIN ß4 for their nuclear accumulation. The combination of an importin and its two antagonistic cargos in PLT1 transcription may have logistic benefits in fine-tuning the transcription of PLT1 in root meristem.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Carioferinas/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Carioferinas/genética , Meristema/genética , Meristema/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Fatores de Transcrição/genética
6.
Plant Cell ; 32(4): 1270-1284, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32086364

RESUMO

Male and female gametophytes are generated from micro- or megaspore mother cells through consecutive meiotic and mitotic cell divisions. Defects in these divisions often result in gametophytic lethality. Gametophytic lethality was also reported when genes encoding ribosome-related proteins were mutated. Although numerous ribosomal proteins (RPs) have been identified in plants based on homology with their yeast and metazoan counterparts, how RPs are regulated, e.g., through dynamic subcellular targeting, is unknown. We report here that an Arabidopsis (Arabidopsis thaliana) importin ß, KETCH1 (karyopherin enabling the transport of the cytoplasmic HYL1), is critical for gametogenesis. Karyopherins are molecular chaperones mediating nucleocytoplasmic protein transport. However, the role of KETCH1 during gametogenesis is independent of HYPONASTIC LEAVES 1 (HYL1), a previously reported KETCH1 cargo. Instead, KETCH1 interacts with several RPs and is critical for the nuclear accumulation of RPL27a, whose mutations caused similar gametophytic defects. We further showed that knocking down KETCH1 caused reduced ribosome biogenesis and translational capacity, which may trigger the arrest of mitotic cell cycle progression and lead to gametophytic lethality.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Gametogênese Vegetal , Carioferinas/metabolismo , Proteínas Ribossômicas/metabolismo , Arabidopsis/genética , Arabidopsis/ultraestrutura , Pontos de Checagem do Ciclo Celular , Núcleo Celular/ultraestrutura , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Mutação com Perda de Função/genética , Óvulo Vegetal/metabolismo , Óvulo Vegetal/ultraestrutura , Pólen/crescimento & desenvolvimento , Pólen/ultraestrutura , Ligação Proteica , Biossíntese de Proteínas , Proteínas de Ligação a RNA/metabolismo , Ribossomos/metabolismo , Sementes/metabolismo , Sementes/ultraestrutura
7.
Front Plant Sci ; 11: 602701, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391314

RESUMO

Stomata are a key land plant innovation that permit the regulation of gaseous exchanges between the plant interior and the surrounding environment. By opening or closing, stomata regulate transpiration of water though the plant; and these actions are coordinated with acquisition of CO2 for photosynthesis. Stomatal movement is controlled by various environmental and physiological factors and associates with multiple intracellular activities, among which the dynamic remodeling of vacuoles plays a crucial role. Phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is critical for dynamic remodeling of vacuoles. Its production requires a PI(3,5)P2-metabolizing complex consisting of FAB1/PIKfyve kinases, SAC phosphatases, and the scaffolding protein VAC14. Although genetic or pharmacological downregulation of PI(3,5)P2 causes hyposensitivity to ABA-induced stomatal closure, whether the effect of PI(3,5)P2 on stomatal movement is cell-autonomous and the physiological consequences of its reduction were unclear. We report that downregulating Arabidopsis VAC14 specifically in guard cells by artificial microRNAs (amiR-VAC14) results in enlarged guard cells and hyposensitivity to ABA- and dark-induced stomatal closure. Vacuolar fission during stomatal closure is compromised by downregulating VAC14 in guard cells. Exogenous application of PI(3,5)P2 rescued the amiR-VAC14 phenotype whereas PI(3,5)P2 inhibitor YM201636 caused wild-type plants to have inhibited stomatal closure. We further show that downregulating VAC14 specifically in guard cells impairs drought tolerance, suggestive of a key role of guard cell-produced PI(3,5)P2 in plant fitness.

8.
J Minim Invasive Gynecol ; 26(1): 94-99, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29678756

RESUMO

STUDY OBJECTIVES: To evaluate the efficacy of a new crosslinked hyaluronan (NCH) gel in reducing the formation of intrauterine adhesions (IUAs) after dilation and curettage (D&C). DESIGN: Randomized controlled trial (Canadian Task Force classification I). SETTINGS: Six hospitals for maternal and child healthcare in China. PATIENTS: A total of 300 patients were randomized to undergo D&C for delayed miscarriage without previous history of D&C. Twenty-six patients (9%) were lost to follow-up and were excluded from the analysis. INTERVENTIONS: Women were randomly assigned to D&C alone (control group; n = 150) or D&C plus NCH gel application (NCH gel group; n = 150) with 1:1 allocation. MEASUREMENTS AND MAIN RESULTS: All patients were evaluated using the American Fertility Society classification of IUAs during follow-up diagnostic hysteroscopy, scheduled at 3 months after D&C procedure. The primary endpoint was the number of women with IUAs at 3 months, and the secondary endpoints were adhesion scores and severity of IUAs. Postoperative efficacy data were available for 274 women (137 in each group). Intrauterine adhesion formations were observed in 13 of the 137 women (9.5%) in the NCH gel group and in 33 of the 137 women (24.1%) in the control group (p = .0012; relative risk [RR], 0.3939; 95% confidence interval [CI], 0.2107-0.7153), a difference of 14.6% (95% CI, 5.92%-23.28%) between the 2 groups. The extent of intrauterine cavity involved, type of adhesion and menstrual pattern, and cumulative adhesion scores were significantly lower in the NCH gel group compared with the control group (p = .0007, .008, .0012, and .0006, respectively). The proportion of women with moderate to severe IUAs was significantly lower in the NCH gel group than that in the control group (1 of 137 [0.7%] vs 16 of 137 [11.7%]; p = .0002; RR, 0.0625; 95% CI, 0.0084-0.4648), a difference of 11.95% (95% CI, 5.39%-16.51%) between the 2 groups. CONCLUSIONS: The current study demonstrates that IUAs are frequently formed after D&C for delayed miscarriage in women without a previous history of D&C procedures, and the application of NCH gel significantly reduces IUA formation.


Assuntos
Aborto Espontâneo/cirurgia , Dilatação e Curetagem/efeitos adversos , Géis , Ácido Hialurônico/administração & dosagem , Aderências Teciduais/prevenção & controle , Doenças Uterinas/prevenção & controle , Adolescente , Adulto , China , Reagentes de Ligações Cruzadas/química , Dilatação , Método Duplo-Cego , Feminino , Humanos , Ácido Hialurônico/química , Histeroscopia/efeitos adversos , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Aderências Teciduais/cirurgia , Doenças Uterinas/cirurgia , Adulto Jovem
9.
Mol Med Rep ; 10(2): 593-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24858729

RESUMO

The transdermal delivery system (TDS) is able to obtain a systemic therapeutic effect by administration through the skin, which has low side effects and is able to maintain a sustained blood concentration. However, due to the barrier presented by the stratum corneum, numerous drugs have poor percutaneous permeability. Therefore, the improvement of skin permeability is key to TDS. The main method of promoting transdermal absorption is through the usage of penetration enhancers. Dimethyl sulfoxide (DMSO) is a commonly used penetration enhancer, which has anti­inflammatory analgesic effects and is able to penetrate the skin. Retinoic acid (RA) and lipolanthionine peptide (LP) may also benefit the permeation efficiency of TDS. Therefore, the present study examined the function of DMSO, RA and LP as penetration enhancers in TDS. Firstly, the optimum concentration of DMSO was confirmed by detecting the expression of the LacZ gene in vitro. Secondly, different combinations of LP, RA and DMSO were applied to mouse skin to analyze the penetration enhancer combination with the greatest efficacy. All the animals were divided into five groups: The RA + LP + DMSO + pORF­LacZ group, the RA + DMSO + pORF­LacZ group, the LP + DMSO + pORF­LacZ group, the DMSO + pORF-LacZ group and the control group. Skin was soaked in combinations of LP, RA and DMSO for seven days and then the pORF­LacZ plasmids were daubed onto the skin once daily three days. On the 11th day, all the animals were sacrificed by cervical dislocation and the skin and blood samples were collected. The blood samples were used to detect the expression of the LacZ gene by quantitative polymerase chain reaction and the skin samples were used to detect the expression of claudin­4 and zonula occluden­1 (ZO­1) proteins by immunohistochemistry and western blot analysis. The results demonstrated that the combination of LP, RA and DMSO exhibited the greatest transdermal delivery efficiency, which verified that RA and LP were able to increase the penetration effects. Following treatment with LP, the symptoms of dermal edema were relieved and the capillaries contracted, which suggested that LP was a safe and effective penetration enhancer able to reduce the side­effects caused by DMSO. The present study provides a guideline for the synthesis of novel penetration enhancers.


Assuntos
Peptídeos/farmacologia , Permeabilidade/efeitos dos fármacos , Receptor 2 Toll-Like/antagonistas & inibidores , Administração Cutânea , Animais , Claudina-4/metabolismo , Dimetil Sulfóxido/farmacologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos/genética , Plasmídeos/metabolismo , Pele/efeitos dos fármacos , Pele/patologia , Receptor 2 Toll-Like/metabolismo , Tretinoína/farmacologia , Proteína da Zônula de Oclusão-1/metabolismo
10.
AIDS Care ; 23(8): 988-97, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21390879

RESUMO

HIV-positive Latino and African-American young men who have sex with men (YMSM) have low rates of engagement and retention in HIV care. An evaluation of a youth-focused case management intervention (YCM) designed to improve retention in HIV care is presented. HIV-positive Latino and African-American YMSM, ages 18-24, who were newly diagnosed with HIV or in intermittent HIV care, were enrolled into a psychosocial case management intervention administered by Bachelor-level peer case managers at two HIV clinics in Los Angeles County, California. Participants met weekly with a case manager for the first two months and monthly for the next 22 months. Retention in HIV primary care at three and six months of follow-up was evaluated as were factors associated with retention in care. From April 2006 to April 2009, 61 HIV-positive participants were enrolled into the intervention (54% African-American, 46% Latino; mean age 21 years). At the time of enrollment into the intervention, 78% of the YMSM had a critical or immediate need for stable housing, nutrition support, substance abuse treatment, or mental health services. Among intervention participants (n=61), 90% were retained in primary HIV care at three months and 70% at six months. Among those who had previously been in intermittent care (n=33), the proportion attending all HIV primary care visits in the previous six months increased from 7% to 73% following participation in the intervention (p<0.0001). Retention in HIV care at six months was associated with increased number of intervention visits (p=0.05), more hours in the intervention (p=0.02), and prescription of HAART. These data highlight the critical needs of HIV-positive African-American and Latino YMSM and demonstrate that a clinic-based YCM can be effective in stabilizing hard-to-reach clients and retaining them in consistent HIV care.


Assuntos
Negro ou Afro-Americano , Administração de Caso/organização & administração , Hispânico ou Latino , Adesão à Medicação/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Infecções por HIV/tratamento farmacológico , Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade Masculina , Humanos , Masculino , Adulto Jovem
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