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Hydrogen sulfide (H2S) has a comprehensive contribution to the normal operation and stability of organisms and is also present in environmental water samples and food deterioration. Thus, it is exceedingly promising and significant to develop a highly sensitive detection technique for tracing H2S. Inspired by this, we designed and synthesized a new fluorescent probe 2-[3-[2-[3-bromo-4-(2,4- dinitrobenzenesulfonate)] ethenyl]-5,5-dimethyl-2-cyclohexen-1-ylidene]propanedinitrile (SP-Br) for hydrosulfide ion detection by introducing bromine atom. Compared with reported H2S probes based on the same fluorescent parent, SP-Br has longer fluorescence emission (λem = 670 nm), shorter response time (3 min), lower detection limit (149 nM), and wider detection range (0-30 nM). SP-Br can emit weak yellow fluorescence, and the emission intensity at 670 nm is considerably enhanced in the presence of hydrosulfide ions. The identification mechanism of hydrosulfide ion by SP-Br was verified by high-resolution mass spectrometry, fluorescence, and UV-vis absorption spectroscopy. In addition, SP-Br has been successfully applied to the monitoring of actual water samples and beer samples and has certain development prospects and value in the fields of environmental pollution and food quality analysis.
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BACKGROUND: Gastric cancer (GC) is prevalent and aggressive, especially when patients have distant lung metastases, which often places patients into advanced stages. By identifying prognostic variables for lung metastasis in GC patients, it may be possible to construct a good prediction model for both overall survival (OS) and the cumulative incidence prediction (CIP) plot of the tumour. AIM: To investigate the predictors of GC with lung metastasis (GCLM) to produce nomograms for OS and generate CIP by using cancer-specific survival (CSS) data. METHODS: Data from January 2000 to December 2020 involving 1652 patients with GCLM were obtained from the Surveillance, epidemiology, and end results program database. The major observational endpoint was OS; hence, patients were separated into training and validation groups. Correlation analysis determined various connections. Univariate and multivariate Cox analyses validated the independent predictive factors. Nomogram distinction and calibration were performed with the time-dependent area under the curve (AUC) and calibration curves. To evaluate the accuracy and clinical usefulness of the nomograms, decision curve analysis (DCA) was performed. The clinical utility of the novel prognostic model was compared to that of the 7th edition of the American Joint Committee on Cancer (AJCC) staging system by utilizing Net Reclassification Improvement (NRI) and Integrated Discrimination Improvement (IDI). Finally, the OS prognostic model and Cox-AJCC risk stratification model modified for the AJCC system were compared. RESULTS: For the purpose of creating the OS nomogram, a CIP plot based on CSS was generated. Cox multivariate regression analysis identified eleven significant prognostic factors (P < 0.05) related to liver metastasis, bone metastasis, primary site, surgery, regional surgery, treatment sequence, chemotherapy, radiotherapy, positive lymph node count, N staging, and time from diagnosis to treatment. It was clear from the DCA (net benefit > 0), time-dependent ROC curve (training/validation set AUC > 0.7), and calibration curve (reliability slope closer to 45 degrees) results that the OS nomogram demonstrated a high level of predictive efficiency. The OS prediction model (New Model AUC = 0.83) also performed much better than the old Cox-AJCC model (AUC difference between the new model and the old model greater than 0) in terms of risk stratification (P < 0.0001) and verification using the IDI and NRI. CONCLUSION: The OS nomogram for GCLM successfully predicts 1- and 3-year OS. Moreover, this approach can help to appropriately classify patients into high-risk and low-risk groups, thereby guiding treatment.
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The MnSn monolayer synthesized recently is a novel two-dimensional ferromagnetic material with a hexagonal lattice, in which three Mn atoms come together to form a trimer, making it remarkably different from other magnetic two-dimensional materials. Most impressively, there occurs a sharp increase of the Curie temperature from 54 to 225 K when the number of layers increases from 1 to 3. However, no quantitative explanation has been reported in previous studies. Herein, by means of the first-principles calculation method and the Monte Carlo method, we demonstrate that strong interlayer ferromagnetic coupling plays an essential role in enhancing its critical temperature, which acts as a magnetic field to stabilize the ferromagnetism in MnSn multilayers. Our work not only explains the sharp increase of the Curie temperature of the MnSn film in experiments but also reveals that the interlayer coupling is a new routine to achieve high-temperature ferromagnetism in two-dimensional materials.
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OBJECTIVE: To investigate the relationship between 5-HT transporter gene-linked polymorphism (5-HTTPLR) and the clinical characters of premature ejaculation in Han Chinese population. METHODS: By case-control study approach, we set primary premature ejaculation (PPE) group (119 cases), secondary premature ejaculation (SPE) group (60 cases) with IELT < 1 min in more than 90% coitus and normal control group (90 cases) with IELT ≥ 3 min. The gene polymorphism of the 5-HTT was detected by polymerase chain reaction analysis in all the cases, and the gene frequency differences among the three groups were evaluated. RESULTS: The frequency of the genotype S/S was higher in PPE group than in normal control group(51.3% vs. 37.8%,P<0.01), and the frequency of genetype L/S was lower in PPE group than in normal vontrol group(28.6% vs. 34.4%,P<0.05).The S allele was higher in PPE group than in control group (P<0.05), but there was no difference between the SPE group and the normal control group. CONCLUSION: The 5-HTTLPR polymorphism is associated with PPE, which shows that genetics may play an important role in the occurrence of PPE but not of SPE. The etiology of PPE and SPE is different.
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Eyaculación/genética , Polimorfismo Genético/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Disfunciones Sexuales Fisiológicas/genética , Adulto , Estudios de Casos y Controles , China/etnología , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Pyrazoline derivatives have been used widely in dyeing industry as fluorescent whitening agents due to their excellent capability. According to Schellhammer theory of the relation between chemical structure and fluorescent quality, six new fluorescent compounds were designed and synthesized which contained the benzothiazole group in the 1-pyrazoline, the indole group in the 3-pyrazoline and the derivatives of phenyl in the 5-pyrazoline. The structure of target compounds was confirmed by IR, 1H NMR, MS and elementary analysis. The fluorescence spectra showed that these compounds had good fluorescence. They could absorb ultraviolet light at near 353 nm. The fluorescence maximum emission wavelengths were about 430-443 nm. It was a kind of promising fluorescence compounds. The largest fluorescence emission wavelength and the fluorescence intensity were related to the substituted group of the compounds. When the 6-Br group was introduced into benzothiazole, the fluorescence emission wavelength exhibited a blue shift, and the fluorescence intensity increased. Otherwise, the CH3 group was introduced into benzothiazole, the fluorescence emission wavelength red-shift occurred, and the intensity was lower. The fluorescence quantum yield of the compounds was little affected by the substituted group and polarity of the solvent The relative fluorescence intensity and fluorescence quantum yield were not directly related.
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OBJECTIVE: To evaluate the efficacy and safety of selective serotonin re-uptake inhibitors (SSRIs) in the treatment of premature ejaculation (PE). METHODS: From MEDLINE (Jan, 1950-Mar, 2008), EMBASE (Jan, 1980-Mar, 2008), The Cochrane Library (Issue 1, 2008) and CNKI (Jan, 1979-Mar, 2008), we retrieved and screened the randomized controlled trials (RCT) and randomized crossover trials (RT) as well as various related data, published and unpublished, on the treatment of PE with SSRIs. The methodological quality of the included trials was evaluated by 2 reviewers. Meta-analyses were conducted with RevMan 5.0 on the homogeneous studies. RESULTS: Totally 22 studies on 4 291 patients were included. Meta-analyses showed that after treated with sertraline, fluoxetine, paroxetine, citalopram, dapoxetine and fluvoxamine, the WMD (95% CI) values of the changes in intravaginal ejaculatory latency time (IELT) were 2.63 (1.80, 3.46), 2.21 (1.50, 2.92), 4.31 (2.71, 5.91), 3.82 (3.39, 4.25), 1.57 (1.31, 1.84) and 0.01 (0.71, 0.73) respectively; the RR (95% CI) values of the sexual satisfaction rate of the patients were 1.65 (1.12, 2.43), 2.93 (0.50, 17.31), 3.08 (2.27, 4.17), 2.48 (1.99, 3.09) and 2.93 (2.36, 3.65), and those of their partners were 1.47 (0.98, 2.21), 2.88 (0.38, 21.77), 4.81 (3.15, 7.36), 5.38 (3.75, 7.72) and 2.91 (1.09, 7.78) respectively for sertraline, fluoxetine, paroxetine, citalopram and dapoxetine. CONCLUSION: All the known SSRIs but fluvoxamine could prolong IELT, and some could improve the sexual satisfaction of both the patients and their partners, but their adverse effects should be noted. The moderate possibility of selection bias and publication bias in the included studies might have a negative impact on the evidence intensity of our results. We expect more reliable evidence from more randomized controlled trials.
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Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Disfunciones Sexuales Fisiológicas/tratamiento farmacológico , Humanos , MEDLINE , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
Dysfunction in alpha7 nicotinic acetylcholine receptor (nAChR), a member of the Cys-loop ligand-gated ion channel superfamily, is responsible for attentional and cognitive deficits in Alzheimer's disease (AD). To provide useful information for finding drug candidates for the treatment of AD, a study was carried out according to the following procedures. (1) DMXBA, a partial agonist of the alpha7 nAChR, was used as a template molecule. (2) To reduce the number of compounds to be considered, the similarity search and flexible alignment were conducted to exclude those molecules which did not match the template. (3) The molecules thus obtained were docked to alpha7 nAChR. (4) To gain more structural information, the molecular dynamics (MD) simulations were carried out for 9 most favorable agonists obtained by the aforementioned docking studies. (5) By analyzing the hydrogen bond interaction and hydrophobic/hydrophilic interaction, the following seven compounds were singled out as possible drug candidates for AD therapy: gx-50, gx-51, gx-52, gx-180, open3d-99008, open3d-51265, open3d-60247.