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1.
Phytomedicine ; 130: 155735, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38810557

RESUMO

BACKGROUND: Gastric cancer (GC) is difficult to treat with currently available treatments. Securinine (SCR) has a lengthy history of use in the treatment of disorders of the nervous system, and its anticancer potential has been gaining attention in recent years. The aim of this study was to explore the repressive effect of SCR on GC and its fundamental mechanism. METHODS: The efficacy of SCR in GC cells was detected by MTT assays. Colony formation, flow cytometry and Transwell assays were used to assess the changes in the proliferation, apoptosis, cell cycle distribution, migration and invasion of GC cells after treatment. AGS (human gastric carcinoma cell)-derived xenografts were used to observe the effect of SCR on tumor growth in vivo. The molecular mechanism of action of SCR in GC was explored via RNA sequencing, bioinformatics analysis, Western blotting, molecular docking, and immunohistochemistry. RESULTS: SCR was first discovered to inhibit the proliferation, migration, and invasion of GC cells while initiating apoptosis and cell cycle arrest in vitro. It was also established that SCR has excellent anticancer effects in vivo. Interestingly, AURKA acts as a crucial target of SCR, and AURKA expression can be blocked by SCR. Moreover, this study revealed that SCR suppresses the cell cycle and the ß-catenin/Akt/STAT3 pathways, which were previously reported to be regulated by AURKA. CONCLUSION: SCR exerts a notable anticancer effect on GC by targeting AURKA and blocking the cell cycle and ß-catenin/Akt/STAT3 pathway. Thus, SCR is a promising pharmacological option for the treatment of GC.


Assuntos
Aurora Quinase A , Azepinas , Proteínas Proto-Oncogênicas c-akt , Fator de Transcrição STAT3 , Neoplasias Gástricas , beta Catenina , Neoplasias Gástricas/tratamento farmacológico , Humanos , Fator de Transcrição STAT3/metabolismo , Aurora Quinase A/metabolismo , Linhagem Celular Tumoral , Animais , beta Catenina/metabolismo , Azepinas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Compostos Heterocíclicos de Anel em Ponte/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Camundongos Nus , Dioxolanos/farmacologia , Camundongos Endogâmicos BALB C , Camundongos , Antineoplásicos Fitogênicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Carcinogênese/efeitos dos fármacos , Simulação de Acoplamento Molecular , Lactonas , Piperidinas
2.
Int J Gen Med ; 17: 863-870, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38463441

RESUMO

Purpose: To investigate the predictive value of hemoglobin (Hb) to red blood cell distribution width (RDW) (Hb/RDW) ratio in combination with serum sodium for major adverse cardiovascular events (MACE) in elderly acute heart failure patients with preserved ejection fraction at 30 days after discharge. Methods: 130 elderly acute heart failure patients with preserved ejection fraction were enrolled and followed up at 30 days after discharge. They were classified into the MACE group (n=11) and none-MACE group (n=119). On the day of admission, clinical baseline characteristics were measured and results from laboratory tests were gathered. The correlation and predictive value of Hb/RDW and serum sodium with the occurrence of MACE at 30 days after discharge in acute heart failure patients with preserved ejection fraction in the elderly were analyzed. Results: Spearman correlation analysis showed that the occurrence of MACE was negatively correlated with Hb/RDW, serum sodium (r=-0.209, r=0.291, p<0.05) and Hb/RDW (OR=0.484, 95% CI:0.254, 0.922), serum sodium (OR=0.779, 95% CI:0.646,0.939) were independent risk factors (p<0.05) analyzed by multifactorial logistic. Receiver operating characteristic curves (ROC) analysis showed that the area under the curve (AUC) for the prediction of MACE by Hb/RDW was 0.73, with an optimal threshold of 9.28, sensitivity 81.80%, specificity 70.60%, positive predictive value (PPV) 20.50%, negative predictive value (NPV) 97.70%; the AUC of serum sodium for predicting the occurrence of MACE was 0.76, with an optimal threshold of 140.35 mmol/L, sensitivity 90.90%, specificity 57.10%, PPV 16.40%, NPV 98.60%; and the AUC of Hb/RDW combined serum sodium to predict the occurrence of MACE was 0.83, with sensitivity 90.90%, specificity 78.20%, PPV 27.80% and NPV 98.90%. Conclusion: Hb/RDW and serum sodium had negative correlation with MACE and were independent risk factors of 30-day MACE; Hb/RDW combined with serum sodium can predict 30-day MACE occurrence in elderly acute heart failure patients with preserved ejection fraction.

3.
Prev Med ; 173: 107567, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37286090

RESUMO

According to the randomization method, 82 patients can be divided into two groups, the control group and the study group, each with 41 patients participating in the investigation. All patients in the control group were cared for, and the study group used a health education model. The treatment mode of each group needs to adopt adherence, and it is necessary to maintain a healthy diet, smoking cessation and alcohol cessation, and regular review during the treatment of regular exercise and emotional regulation. To enable patients to accurately grasp health knowledge during treatment, score self-management ability (ESCA), and maintain a level of satisfaction with care. (1) In the study group, the standard treatment of patients directly reached 97.56%, regular review reached 95.12%, regular exercise reached 90.24%, the degree of smoking cessation reached 92.68%. (2) The mastery of disease and health knowledge in the first group (95.12%) was significantly higher than that of (78.05%) (P < 0.05). (3) After the intervention, the first group scored higher for self-responsibility (27.07 ± 3.15), self-awareness (25.59 ± 3.11), health knowledge (40.38 ± 4.54), and self-care skills (36.45 ± 3.19). (4) The nursing satisfaction level of the first group was (92.68%), which was significantly higher than that of the other group (75.61%). According to the conclusions, it can be shown that health education for tumor patients can improve patients' compliance with treatment and mastery of disease health knowledge, which is conducive to improving patients' self-management ability.


Assuntos
Neoplasias Gastrointestinais , Nanopartículas , Humanos , Comportamentos Relacionados com a Saúde , Educação em Saúde , Nanopartículas/uso terapêutico , Cooperação do Paciente , Microambiente Tumoral
4.
bioRxiv ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38168344

RESUMO

Non-spiking sensory hair cells of the auditory and vestibular systems encode a dynamic range of graded signals with high fidelity by vesicle exocytosis at ribbon synapses. Ribeye, the most abundant protein in the synaptic ribbon, is composed of a unique A domain specific for ribbons and a B-domain nearly identical to the transcriptional corepressor CtBP2. CTBP2 and the B-domain of Ribeye contain a surface cleft that binds to proteins harboring a PXDLS/T peptide motif. Little is known about the importance of this binding site in synaptic function. Piccolo has a well-conserved PVDLT motif and we find that overexpressed Ribeye exhibits striking co-localization with Piccolo in INS-cells, while two separate mutants containing mutations in PXDLS/T-binding region, fail to co-localize with Piccolo. Similarly, co-transfected Ribeye and a piccolo fragment containing the PVDLT region co-localize in HEK cells. Expression of wild-type Ribeye-YFP in zebrafish neuromast hair cells returns electron densities to ribbon structures and mostly rescued normal synaptic transmission and morphological phenotypes in a mutant zebrafish lacking most Ribeye. By contrast, Ribeye-YFP harboring a mutation in the PXDLS/T-binding cleft resulted in ectopic electron dense aggregates that did not collect vesicles and the persistence of ribbons lacking electron densities. Furthermore, overexpression failed to return capacitance responses to normal levels. These results point toward a role for the PXDLS/T-binding cleft in the recruitment of Ribeye to ribbons and in normal synaptic function.

5.
Sci Rep ; 12(1): 22604, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585458

RESUMO

Precision radiotherapy needs to manage organ movements to prevent critical organ injury. The purpose of this study is to examine the feasibility of motion control of the lung by suppressing respiratory motion. The non-invasive high frequency oscillatory ventilation (NIHFOV) is a technique commonly used in the protection of lung for patients with acute lung disease. By using a very high respiratory frequency and a low tidal volume, NIHFOV allows gas exchange, maintains a constant mean airway pressure and minimizes the respiratory movements. We tested healthy volunteers NIHFOV to explore the optimal operational parameter setting and the best possible motion suppression achievable. This study was conducted with the approval of Institutional Review Boards of the Wuwei Cancer hospital (approval number: 2021-39) and carried out in accordance with Declaration of Helsinki. The study comprises two parts. Twenty three healthy volunteers participated in the first part of the study. They had 7 sessions of training with the NIHFOV. The duration of uninterrupted, continuous breathing under the NIHFOV and the optimal operational machine settings were defined. Eight healthy volunteers took part in the second part of the study and underwent 4-dimensional CT (4DCT) scanning with and without NIHFOV. Their respiratory waveform under free breathing (FB) and NIHFOV were recorded. The maximum range of motion of the diaphragm from the two scannings was compared, and the variation of bilateral lung volume was obtained to evaluate the impact of NIHFOV technique on lung volume. The following data were collected: comfort score, transcutaneous partial pressure of oxygen (PtcO2), transcutaneous partial pressure of carbon dioxide (PtcCO2), and pulse rate. Data with and without NIHFOV were compared to evaluate its safety, physiological impacts and effect of lung movement suppression. All the volunteers completed the training sessions eventlessly, demonstrating a good tolerability of the procedure. The median NIHFOV-on time was 32 min (22-45 min), and the maximum range of motion in the cephalic-caudal direction was significantly reduced on NIHFOV compared with FB (1.8 ± 0.8 cm vs 0.3 ± 0.1 cm, t = - 3.650, P = 0.003); the median range of motion was only 0.3 ± 0.1 cm on NIHFOV with a good reproducibility. The variation coefficient under NIHFOV of the right lung volume was 2.4% and the left lung volume was 9.2%. The PtcO2 and PtcCO2 were constantly monitored during NIHFOV. The medium PtcCO2 under NIHFOV increased lightly by 4.1 mmHg (interquartile range [IQR], 4-6 mmHg) compared with FB (t = 17.676, P < 0.001). No hypercapnia was found, PtcO2 increased significantly in all volunteers during NIHFOV (t = 25.453, P < 0.001). There was no significant difference in pulse rate between the two data sets (t = 1.257, P = 0.233). NIHFOV is easy to master in healthy volunteers to minimize respiratory movement with good tolerability and reproducibility. It is a feasible approach for lung motion control and could potentially be applied in accurate radiotherapy including carbon-ion radiotherapy through suppression of respiratory movement.


Assuntos
Ventilação de Alta Frequência , Humanos , Voluntários Saudáveis , Reprodutibilidade dos Testes , Pulmão/diagnóstico por imagem , Respiração
6.
Front Oncol ; 12: 1012863, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36568183

RESUMO

Introduction: A number of evidences have proved that "Nostoc commune" Vauch can improve human immunity and prevent diseases, however, the specific mechanism remains unclear. The biological activity of the main protein component of "Nostoc commune" Vauch extracellular matrix- a water-stress protein (WSP) still needs to be elucidated. Methods: In our study, we validated the role of WSP in gastric cancer metastasis at the cellular level, the organoid level and in mouse models, and also studied the role of EGFRVIII and downstream signaling molecules after WSP treatment. Results: We found that WSP can significantly inhibit the metastasis of gastric cancer cells. Interestingly, we found that the anti-metastasis ability of WSP on gastric cancer was related to membrane protein receptor EGFRVIII, which was realized by inhibiting the downstream EGFRVIII signaling pathway. In terms of mechanism, WSP can inhibit the downstream EGFRVIII signaling pathway Akt-PI3K and further inhibit the secretion of cancer-related metastasis proteins such as MMP2 and MMP9, thus, significantly affecting the metastasis of gastric cancer cells. Discussion: Given the anticancer properties of WSP, drug developers and manufacturers can further develop protein drugs for cancer patients using protein engineering techniques based on the properties of WSP.

7.
Science ; 378(6616): 186-192, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36227977

RESUMO

Studies of the proteome would benefit greatly from methods to directly sequence and digitally quantify proteins and detect posttranslational modifications with single-molecule sensitivity. Here, we demonstrate single-molecule protein sequencing using a dynamic approach in which single peptides are probed in real time by a mixture of dye-labeled N-terminal amino acid recognizers and simultaneously cleaved by aminopeptidases. We annotate amino acids and identify the peptide sequence by measuring fluorescence intensity, lifetime, and binding kinetics on an integrated semiconductor chip. Our results demonstrate the kinetic principles that allow recognizers to identify multiple amino acids in an information-rich manner that enables discrimination of single amino acid substitutions and posttranslational modifications. With further development, we anticipate that this approach will offer a sensitive, scalable, and accessible platform for single-molecule proteomic studies and applications.


Assuntos
Proteoma , Proteômica , Aminoácidos/química , Aminopeptidases , Peptídeos/química , Proteômica/métodos , Semicondutores , Análise de Sequência de Proteína/métodos
8.
Comput Intell Neurosci ; 2022: 2645528, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072734

RESUMO

To many hospitals' management as well as to patients, the nursing service is one of the most important aspects. Many diseases like sugar, blood pressure, urine passage, and gas are a little bit dangerous to handle by patients themselves. The earlier stage models are unable to give good services to patients; therefore, an advanced JHE: Effect of 1 + N extended nursing service is necessary to crossover the above limitations. Colostomy and colorectal cancers are very dangerous syndromes thus, disease monitoring is so difficult. In this research work, an extended JHE: Effect of 1 + N extended nursing service modeling is discussed with experimental modeling. Apart from conventional nursing care provided by the observation group, it was given online training as well as service providing. Self-efficacy and self-care competence were assessed in both groups 6 months after the discharge. Quality of life and mental health were also assessed. Besides, their dimensional and total self-care ability scores, and the observation group's self-efficacy ratings were substantially higher than those of the control group (P 0.05) after the intervention. It was observed that the intervention group's 6-month adjustment to the stoma was statistically more favorable than the control group's (P 0.001), and only the intervention group showed a significantly major change (P 0.001) between their two evaluations. This proposed methodology can improve the accuracy rate by 93.23%, and succussive treatment rate of 92.14% had been attained.


Assuntos
Colostomia , Serviços de Enfermagem , Colostomia/psicologia , Humanos , Qualidade de Vida , Autoeficácia
9.
J Environ Radioact ; 255: 107014, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36179460

RESUMO

The individual dose caused by airborne effluents varies with the height of the chimney. In order to reduce the individual dose caused by uranium enrichment facilities, the height of the chimney is optimized, and considering the impact of radioactive effluents within 5 km of the site, the Cairdos program is used to simulate and predict the long-term atmospheric diffusion factors and individual dose distribution.The results showed that 234U had a greater impact on individual dose contribution, and the long-term dispersion factor and the maximum individualdose appeared in the southeast-east (ESE) direction. The individual dose caused by 10 m, 30 m and 60 m chimneys was 6.78, 3.41 and 1.60 times that of the 80 m chimney, respectively. Therefore, increasing the height of the chimney can effectively reduce the individual dose. The peak value of the individual dose caused by the 150 m and 200 m chimneys was 0.39 and 0.32 times that of the 80 m chimney, respectively. Therefore, When the chimney height is higher than 80m, the extra high chimney can reduce the individual dose, but the decrease of the individual dose is significantly less than the increase of chimney height.


Assuntos
Monitoramento de Radiação , Urânio , Urânio/análise
10.
BMJ Open ; 12(7): e056685, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35777884

RESUMO

OBJECTIVE: The COVID-19 outbreak was first reported in Wuhan, China, and has been acknowledged as a pandemic due to its rapid spread worldwide. Predicting the trend of COVID-19 is of great significance for its prevention. A comparison between the autoregressive integrated moving average (ARIMA) model and the eXtreme Gradient Boosting (XGBoost) model was conducted to determine which was more accurate for anticipating the occurrence of COVID-19 in the USA. DESIGN: Time-series study. SETTING: The USA was the setting for this study. MAIN OUTCOME MEASURES: Three accuracy metrics, mean absolute error (MAE), root mean square error (RMSE) and mean absolute percentage error (MAPE), were applied to evaluate the performance of the two models. RESULTS: In our study, for the training set and the validation set, the MAE, RMSE and MAPE of the XGBoost model were less than those of the ARIMA model. CONCLUSIONS: The XGBoost model can help improve prediction of COVID-19 cases in the USA over the ARIMA model.


Assuntos
COVID-19 , Modelos Estatísticos , COVID-19/epidemiologia , China/epidemiologia , Previsões , Humanos , Incidência , Estados Unidos/epidemiologia
11.
Environ Sci Pollut Res Int ; 29(27): 41534-41543, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35094276

RESUMO

The COVID-19 outbreak emerged in Wuhan, China, and was declared a global pandemic in March 2020. This study aimed to explore the association of daily mean temperature with the daily counts of COVID-19 cases in Beijing, Shanghai, Guangzhou, and Shenzhen, China. Data on daily confirmed cases of COVID-19 and daily mean temperatures were retrieved from the 4 first-tier cities in China. Distributed lag nonlinear models (DLNMs) were used to assess the association between daily mean temperature and the daily cases of COVID-19 during the study period. After controlling for the imported risk index and long-term trends, the distributed lag nonlinear model showed that there were nonlinear and lag relationships. The daily cumulative relative risk decreased for every 1.0 °C change in temperature in Shanghai, Guangzhou, and Shenzhen. However, the cumulative relative risk increased with a daily mean temperature below - 3 °C in Beijing and then decreased. Moreover, the delayed effects of lower temperatures mostly occurred within 6-7 days of exposure. There was a negative correlation between the cumulative relative risk of COVID-19 incidence and temperature, especially when the temperature was higher than - 3 °C. The conclusions from this paper will help government and health regulators in these cities take prevention and protection measures to address the COVID-19 crisis and the possible collapse of the health system in the future.


Assuntos
COVID-19 , COVID-19/epidemiologia , China/epidemiologia , Cidades/epidemiologia , Humanos , Incidência , Temperatura , Fatores de Tempo
12.
Environ Sci Pollut Res Int ; 29(9): 13386-13395, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34595708

RESUMO

This study sought to identify the spatial, temporal, and spatiotemporal clusters of COVID-19 cases in 366 cities in mainland China with the highest risks and to explore the possible influencing factors of imported risks and environmental factors on the spatiotemporal aggregation, which would be useful to the design and implementation of critical preventative measures. The retrospective analysis of temporal, spatial, and spatiotemporal clustering of COVID-19 during the period (January 15 to February 25, 2020) was based on Kulldorff's time-space scanning statistics using the discrete Poisson probability model, and then the logistic regression model was used to evaluate the impact of imported risk and environmental factors on spatiotemporal aggregation. We found that the spatial distribution of COVID-19 cases was nonrandom; the Moran's I value ranged from 0.017 to 0.453 (P < 0.001). One most likely cluster and three secondary likely clusters were discovered in spatial cluster analysis. The period from February 2 to February 9, 2020, was identified as the most likely cluster in the temporal cluster analysis. One most likely cluster and seven secondary likely clusters were discovered in spatiotemporal cluster analysis. Imported risk, humidity, and inhalable particulate matter PM2.5 had a significant impact on temporal and spatial accumulation, and temperature and PM10 had a low correlation with the spatiotemporal aggregation of COVID-19. The information is useful for health departments to develop a better prevention strategy and potentially increase the effectiveness of public health interventions.


Assuntos
COVID-19 , China , Cidades , Análise por Conglomerados , Humanos , Incidência , Estudos Retrospectivos , SARS-CoV-2 , Análise Espaço-Temporal
13.
BMC Infect Dis ; 21(1): 839, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34412581

RESUMO

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is still attracting public attention because of its outbreak in various cities in China. Predicting future outbreaks or epidemics disease based on past incidence data can help health departments take targeted measures to prevent diseases in advance. In this study, we propose a multistep prediction strategy based on extreme gradient boosting (XGBoost) for HFRS as an extension of the one-step prediction model. Moreover, the fitting and prediction accuracy of the XGBoost model will be compared with the autoregressive integrated moving average (ARIMA) model by different evaluation indicators. METHODS: We collected HFRS incidence data from 2004 to 2018 of mainland China. The data from 2004 to 2017 were divided into training sets to establish the seasonal ARIMA model and XGBoost model, while the 2018 data were used to test the prediction performance. In the multistep XGBoost forecasting model, one-hot encoding was used to handle seasonal features. Furthermore, a series of evaluation indices were performed to evaluate the accuracy of the multistep forecast XGBoost model. RESULTS: There were 200,237 HFRS cases in China from 2004 to 2018. A long-term downward trend and bimodal seasonality were identified in the original time series. According to the minimum corrected akaike information criterion (CAIC) value, the optimal ARIMA (3, 1, 0) × (1, 1, 0)12 model is selected. The index ME, RMSE, MAE, MPE, MAPE, and MASE indices of the XGBoost model were higher than those of the ARIMA model in the fitting part, whereas the RMSE of the XGBoost model was lower. The prediction performance evaluation indicators (MAE, MPE, MAPE, RMSE and MASE) of the one-step prediction and multistep prediction XGBoost model were all notably lower than those of the ARIMA model. CONCLUSIONS: The multistep XGBoost prediction model showed a much better prediction accuracy and model stability than the multistep ARIMA prediction model. The XGBoost model performed better in predicting complicated and nonlinear data like HFRS. Additionally, Multistep prediction models are more practical than one-step prediction models in forecasting infectious diseases.


Assuntos
Febre Hemorrágica com Síndrome Renal , China/epidemiologia , Previsões , Febre Hemorrágica com Síndrome Renal/epidemiologia , Humanos , Incidência , Modelos Estatísticos , Estações do Ano
14.
Org Biomol Chem ; 15(7): 1642-1650, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28127599

RESUMO

In the field of chiral recognition, reported chiral discrimination by 1H NMR spectroscopy has mainly focused on various chiral analytes with a single chiral center, regarded as standard chiral substrates to evaluate the chiral discriminating abilities of a chiral auxiliary. Among them, chiral α-hydroxy acids, α-amino acids and their derivatives are chiral organic molecules involved in a wide variety of biological processes, and also play an important role in the area of preparation of pharmaceuticals, as they are part of the synthetic process in the production of chiral drug intermediates and protein-based drugs. In this paper, several α-hydroxy acids and N-Ts-α-amino acids were used to evaluate the chiral discriminating abilities of tetraaza macrocyclic chiral solvating agents (TAMCSAs) 1a-1d by 1H NMR spectroscopy. The results indicate that α-hydroxy acids and N-Ts-α-amino acids were successfully discriminated in the presence of TAMCSAs 1a-1d by 1H NMR spectroscopy in most cases. The enantiomers of the α-hydroxy acids and N-Ts-α-amino acids were assigned based on the change of integration of the 1H NMR signals of the corresponding protons. The enantiomeric excesses (ee) of N-Ts-α-amino acids 11 with different optical compositions were calculated based on the integration of the 1H NMR signals of the CH3 protons (Ts group) of the enantiomers of (R)- and (S)-11 in the presence of TAMCSA 1b. At the same time, the possible chiral discriminating behaviors have been discussed by means of the Job plots of (±)-2 with TAMCSAs 1b and proposed theoretical models of the enantiomers of 2 and 6 with TAMCSA 1a, respectively.


Assuntos
Aminoácidos/química , Hidroxiácidos/química , Aminoácidos/síntese química , Hidroxiácidos/síntese química , Compostos Macrocíclicos , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Solubilidade
15.
Cell Rep ; 15(12): 2784-95, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27292637

RESUMO

Synaptic ribbons are structures made largely of the protein Ribeye that hold synaptic vesicles near release sites in non-spiking cells in some sensory systems. Here, we introduce frameshift mutations in the two zebrafish genes encoding for Ribeye and thus remove Ribeye protein from neuromast hair cells. Despite Ribeye depletion, vesicles collect around ribbon-like structures that lack electron density, which we term "ghost ribbons." Ghost ribbons are smaller in size but possess a similar number of smaller vesicles and are poorly localized to synapses and calcium channels. These hair cells exhibit enhanced exocytosis, as measured by capacitance, and recordings from afferent neurons post-synaptic to hair cells show no significant difference in spike rates. Our results suggest that Ribeye makes up most of the synaptic ribbon density in neuromast hair cells and is necessary for proper localization of calcium channels and synaptic ribbons.


Assuntos
Canais de Cálcio/metabolismo , Elétrons , Proteínas do Olho/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Sinapses/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Capacitância Elétrica , Exocitose , Células Ciliadas Auditivas/metabolismo , Homozigoto , Ativação do Canal Iônico , Mutação/genética , Neurônios Aferentes/metabolismo , Técnicas de Patch-Clamp , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/ultraestrutura , Sinapses/ultraestrutura
16.
Proc Natl Acad Sci U S A ; 113(17): E2363-72, 2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-27071085

RESUMO

Mutations in polycystin-1 and transient receptor potential polycystin 2 (TRPP2) account for almost all clinically identified cases of autosomal dominant polycystic kidney disease (ADPKD), one of the most common human genetic diseases. TRPP2 functions as a cation channel in its homomeric complex and in the TRPP2/polycystin-1 receptor/ion channel complex. The activation mechanism of TRPP2 is unknown, which significantly limits the study of its function and regulation. Here, we generated a constitutively active gain-of-function (GOF) mutant of TRPP2 by applying a mutagenesis scan on the S4-S5 linker and the S5 transmembrane domain, and studied functional properties of the GOF TRPP2 channel. We found that extracellular divalent ions, including Ca(2+), inhibit the permeation of monovalent ions by directly blocking the TRPP2 channel pore. We also found that D643, a negatively charged amino acid in the pore, is crucial for channel permeability. By introducing single-point ADPKD pathogenic mutations into the GOF TRPP2, we showed that different mutations could have completely different effects on channel activity. The in vivo function of the GOF TRPP2 was investigated in zebrafish embryos. The results indicate that, compared with wild type (WT), GOF TRPP2 more efficiently rescued morphological abnormalities, including curly tail and cyst formation in the pronephric kidney, caused by down-regulation of endogenous TRPP2 expression. Thus, we established a GOF TRPP2 channel that can serve as a powerful tool for studying the function and regulation of TRPP2. The GOF channel may also have potential application for developing new therapeutic strategies for ADPKD.


Assuntos
Canais de Cátion TRPP/fisiologia , Amilorida/farmacologia , Animais , Cálcio/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Mutação/genética , Mutação Puntual/genética , Rim Policístico Autossômico Dominante/genética , Rutênio Vermelho/farmacologia , Canais de Cátion TRPP/efeitos dos fármacos , Canais de Cátion TRPP/genética , Peixe-Zebra/embriologia
17.
Org Chem Front ; 3(12): 1716-1724, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28191319

RESUMO

1H NMR spectroscopy is often used to discriminate enantiomers of chiral analytes and determine their enantiomeric excess (ee) by various chiral auxiliaries. In reported research, these studies were mainly focused on chiral discriminantion of chiral analytes with only one chiral center. However, many chiral compounds possessing two or more chiral centers are often found in natural products, chiral drugs, products of asymmetric synthesis and biological systems. Therefore, it is necessary to investigate their chiral discrimination by effective chiral auxiliaries using 1H NMR spectroscopy. In this paper, a new class of tetraaza macrocyclic chiral solvating agents (TAMCSAs) with two amide (CONH), two amino (NH) and two phenolic hydroxyl (PhOH) groups has been designed and synthsized for chiral discrimination towards dipeptide derivatives with two chiral centers. These dipeptide derivatives are important chiral species because some of them are used as clinical drugs and special dietary supplements for treatment of human diseases, such as L-alanyl-L-glutamine and aspartame. The results show that these TAMCSAs have excellent chiral discriminating properties and offer multiple detection possibilities pertaining to 1H NMR signals of diagnostic split protons. The nonequivalent chemical shifts (up to 0.486 ppm) of various types of protons of these dipeptide derivatives were evaluated with the assistance of well-resolved 1H NMR signals in most cases. In addition, enantiomeric excesses (ee) of the dipeptide derivatives with different optical compositions have been calculated based on integration of well-separeted proton signals. At the same time, the possible chiral discriminating behaviors have been discussed by means of Job plots, ESI mass spectra and a proposed theoretical model of (±)-G1 with TAMCSA 1c. Additionally, the association constants of enantiomers of (±)-G5 with TAMCSA 1a were calculated by employing the nonlinear curve-fitting method.

18.
Am J Transl Res ; 8(12): 5298-5308, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28078003

RESUMO

Atherosclerosis is an immune-mediated inflammatory process, which acts as the main cause of acute coronary syndrome (ACS). Regulatory CD4+CD25+FOXP3+T cells (Tregs) are thought to play a major role in inhibiting the formation and progression of atherosclerosis. However, the exact role played by Tregs in the pathogenesis of ACS is yet remained unclear. FOXP3 is a key regulator of Treg formation and function. Demethylation at the CpG-rich island of FOXP3 upstream enhancers can alter FOXP3 expression, and may affect Treg function during the development of ACS. This study investigated the immunosuppressive function and methylation status of a FOXP3 upstream enhancer in Tregs in ACS patients. Notably, Tregs from ACS patients exhibited a significantly lower immunosuppressive effect on Teffs. Furthermore, the methylation status of the FOXP3 upstream enhancer was significantly increased in ACS patients. Consistent with these observations, Tregs originated from ACS patients manifested significantly lower levels of FOXP3 mRNA. The immunosuppressive effect of Tregs on Teffs was compromised in ACS patients. Together, our data suggest that examination of the methylation status of the FOXP3 upstream enhancer might be a novel approach to diagnose ACS and to differentiate ACS subtypes.

19.
J Huazhong Univ Sci Technolog Med Sci ; 35(2): 271-277, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25877364

RESUMO

Speckle tracking echocardiography (STE) has been applied to the evaluation of cardiac contraction dysfunction. However, there were few studies on alteration of global and regional STE parameters in the process of myocardial hypertrophy and heart failure. In this study, STE was applied to evaluate the global and regional cardiac function under heart failure and hypertrophy in the mice model of pressure overload. Adult mice were subjected to mild or severe aortic banding with a 25 Gauge (G) or 27 G needle. After surgery, STE and conventional echocardiography were used in the sham group (n=10), mild trans-aortic banding (TAB) group (n=14) and severe TAB group (n=10) for 8 weeks. The results showed that the mice subjected to severe TAB showed a significant change in fractional shortening (FS), left ventricular (LV) mass, and left ventricular end diastolic diameter (LVEDD) (P<0.05 for each). Meanwhile, there were no significant differences in FS and LVEDD between the sham group and mild TAB group during the experimental procedures (P>0.05 for both). STE analysis revealed that longitudinal strain (LS) was significantly decreased in the severe TAB group as compared with the sham and mild TAB groups (P<0.05 for both) from the postoperative week 1. LS in the mild TAB group was reduced as compared to the sham group (P<0.05). Radial strain (RS) and circumferential strain (CS) were significantly decreased in the severe TAB group as compared to the sham group and the mild TAB group (P<0.05 for both) from the postoperative week 1 (P<0.05 for both). Compared to the sham group, CS in the mild TAB group maintained unchanged during the test period, and RS was reduced only on the postoperative week 6 (P<0.05). Finally, regional contraction dysfunction was analyzed in both hypertrophic and failing myocardium in longitudinal and radial directions. It was found that LS was largest in the apex region and RS was smallest in the apex region in the healthy and hypertrophic myocardium. It was also found that compared to the sham group, only base longitudinal strain in the mild TAB group was decreased. Each of regional strain in the severe TAB group was uniformly depressed in radial and longitudinal directions. It is concluded that STE has provided a non-invasive and highly feasible way to explore the global and regional contraction dysfunction in hypertrophic and heart failure myocardium in the murine model of pressure overload.


Assuntos
Cardiomegalia/fisiopatologia , Ecocardiografia/métodos , Insuficiência Cardíaca/fisiopatologia , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
Neuron ; 83(6): 1229-31, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25233300

RESUMO

What underlies the large variation in mEPSC amplitude in the auditory system? And is this variability important? In this issue of Neuron, Li et al. (2014) address the significance of large mEPSCs to auditory processing and Chapochnikov et al. (2014) describe a novel mechanism underlying them.


Assuntos
Potenciais Pós-Sinápticos Excitadores/fisiologia , Exocitose , Células Ciliadas Auditivas Internas/metabolismo , Células Ciliadas Auditivas/metabolismo , Modelos Neurológicos , Neurotransmissores/metabolismo , Transmissão Sináptica/fisiologia , Animais
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