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1.
Dalton Trans ; 52(44): 16184-16188, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37870873

RESUMO

Various naphthalenediimide (NDI) based electron donor-acceptor coordination polymers (D-A CPs) have been constructed and used to explore charge transfer (CT) and electron transfer (ET) behaviors. Up to now, significant progress has been made in the interface contact and electron donor-acceptor ability matching mechanism, while the electronic density effect of the electron donors on the CT and ET behaviors is still not known. Herein, two NDI-based D-A CPs, [Cd2(H2NDI)(IPA)2(H2O)2] (1) and [Cd2(H2NDI)(IPA-OH)2(H2O)2] (2), are constructed using an NDI-based ligand and two aromatic carboxylic acid ligands (H2NDI = 2,7-bis(3,5-dimethyl) dipyrazol-1,4,5,8-naphthalene tetracarboxydiimide, H2IPA = isophthalic acid; and H2IPA-OH = 5-hydroxyisophthalic acid). UV-vis and EPR spectroscopy and DFT calculations analyses reveal that the occurrence of themal electron transfer (TET) in 1 and 2 results from the HOMO of the IPA and IPA-OH lying higher than the LUMO of the NDI. Meanwhile, compared to 1, the UV-vis absorption spectrum of 2 exhibits a significant red shift, which suggests higher electron density of the donor and more electron transfer pathways are beneficial for the occurrence of intermolecular CT. After UV light irradiation, the comparison of the photochromic behavior of 1 and 2 confirms the negative effect of the stronger CT on photoinduced electron transfer (PET). The present study illustrates the delicate modulating effect of electron density on the CT and ET behaviors in D-A CPs.

2.
J Dig Dis ; 20(10): 532-538, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31390161

RESUMO

OBJECTIVES: Some Western reports have shown a proximal shift in colorectal cancer (CRC), but there are few studies in China. This study aimed to provide more information for the management and screening of CRC by investigating trends in the anatomic distribution of CRC among the Chinese population in recent years. METHODS: A retrospective study was conducted on patients with CRC admitted to the Digestive Endoscopy Center of Tianjin Medical University General Hospital between January 2000 and December 2017. Patients were divided into a left-sided colorectal cancer (LSCRC) group and a right-sided colon cancer (RSCC) group. The detection rates of LSCRC and RSCC based on patients' age and sex, and on the time periods were analyzed. RESULTS: A total of 2319 cases were diagnosed with CRC among 75 183 consecutive patients. The prevalence of CRC showed a significant reduction from 2000-2008 to 2009-2017 (3.8% vs 2.7%, P < .001). The proportion of RSCC presented a downtrend from 2000-2008 to 2009-2017 (40.6% vs 37.7%, P > .05). There were slightly more RSCCs in female patients than in male patients, with no significant difference (40.9% vs 36.5%, P > .05). The proportion of RSCC in patients aged ≥50 years was similar to that in younger patients. The alarming symptoms between LSCRC and RSCC showed a significant difference (P < .05). CONCLUSIONS: In the present study, the prevalence of CRC declined significantly with time. However, there did not appear to be a rightward shift in CRC among the patients in Tianjin over the past 18 years.


Assuntos
Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer/estatística & dados numéricos , China/epidemiologia , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores Sexuais
3.
Chem Sci ; 10(14): 3949-3955, 2019 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-31015934

RESUMO

Metal-organic frameworks (MOFs) have emerged as one of the most fascinating libraries of porous materials. In spite of their myriad merits, practical application of most MOFs is restricted due to their high preparation cost because of the complicated organic ligands involved. To address this limitation, we propose to use simple and cheap organic precursors to synthesize MOFs with complicated ligands via "one-pot" in situ reactions of these precursors along with the formation of new MOFs. In this work, we have carefully screened several organic reactions, through which target ligands were generated in situ from easily available reactants during the MOF construction. With this "one-pot" approach, the fabrication of a series of novel MOFs by integrating the organic covalent bond and the coordinate bond has thus been realized through the judicious selection of organic reactions, which effectively simplifies the MOF synthesis process and thus reduces the cost.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 201: 119-127, 2018 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-29742486

RESUMO

Cadmium-caused environmental pollution and diseases have always been worldwide problems. Thus it is extremely urgent to establish a cheap, rapid, simple and selective detection method for trace cadmium in drinking water. In this study, a fluorescence "turn-on" method based on ethylene diamine tetraacetic acid (EDTA)-etched CdTe@CdS quantum dots (QDs) was designed to detect Cd2+. High resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) were utilized for chemical and structural characterization of the as-prepared QDs. Based on chemical etching of EDTA on the surface of CdTe@CdS QDs, specific Cd2+ recognition sites were produced, and then results in fluorescence quenching. The introduction of Cd2+ could identify these sites and restore the fluorescence of the EDTA-QDs system. Under the optimum conditions, the nanoprobe shows a linear response range from 0.05 to 9 µM with a very low detection limit of 0.032 µM. In addition, the reported fluorescence probe in this work displays a good selectivity for trace Cd2+ over other metal ions and an admirable practicability in real water samples.

5.
World J Gastroenterol ; 22(45): 10038-10044, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-28018111

RESUMO

AIM: To analyse the clinical features of patients with the serrated lesions in the upper gastrointestinal tract (UPGI) tract. METHODS: Patients who underwent routine esophagogastroduodenoscopy (EGD) at the Digestive Endoscopy Centre of General Hospital, Tianjin Medical University between January 2011 and December 2015 were consecutively recruited. Patients with UPGI serrated lesions were consecutively identified. The patients' demographics and histopathology were recorded. The colorectal findings for patients who underwent colonoscopy simultaneously or within six months were also extracted from the colonoscopy database. In addition, we analysed differences in colorectal neoplasia detection between the study patients and randomly selected patients matched for age and gender who did not exhibit serrated lesions and who also underwent colonoscopy in the same period. RESULTS: A total of 21 patients out of 98746 patients (0.02%) who underwent EGD were confirmed to have serrated lesions with predominantly crenated, sawtooth-like configurations. The mean age of the 21 patients was (55.3 ± 17.2) years, and 11 patients were male (52.4%). In terms of the locations of the serrated lesions, 17 were found in the stomach (including 3 in the cardia, 9 in the corpus and 5 in the antrum), 3 were found in the duodenum, and 1 was found in the esophagus. Serrated lesions were found in different mucosal lesions, with 14 lesions were detected in polyps (8 hyperplastic polyps and 6 serrated adenomas with low grade dysplasia), 3 detected in Ménétrier gastropathy, 3 detected in an area of inflammation or ulcer, and 1 detected in the intramucosal carcinoma of the duodenum. In addition, colonoscopy data were available for 18 patients, and a significantly higher colorectal adenoma detection rate was observed in the UPGI serrated lesions group than in the randomly selected age- and gender-matched group without serrated lesions who also underwent colonoscopy in the same period (38.9% vs 11.1%, OR = 5.091, 95%CI: 1.534-16.890, P = 0.010). The detection rate of advanced adenoma was also higher in the UPGI serrated lesions group (22.2% vs 4.2%, OR = 6.571, 95%CI: 1.322-32.660, P = 0.028). CONCLUSION: Serrated lesions in the UPGI were detected in various mucosal lesions with different pathological morphologies. Moreover colonoscopy is recommended for the detection of concurrent colorectal adenoma for these patients.


Assuntos
Adenoma/epidemiologia , Carcinoma in Situ/epidemiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Duodenais/epidemiologia , Neoplasias Esofágicas/epidemiologia , Pólipos Intestinais/epidemiologia , Neoplasias Gástricas/epidemiologia , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma in Situ/patologia , Colonoscopia , Neoplasias Colorretais/patologia , Neoplasias Duodenais/patologia , Endoscopia do Sistema Digestório , Neoplasias Esofágicas/patologia , Feminino , Humanos , Pólipos Intestinais/patologia , Masculino , Pessoa de Meia-Idade , Pólipos/epidemiologia , Pólipos/patologia , Estudos Retrospectivos , Neoplasias Gástricas/patologia
6.
World J Gastroenterol ; 22(36): 8137-48, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27688655

RESUMO

Serotonin (5-HT) and the serotonin transporter (SERT) have earned a tremendous amount of attention regarding the pathogenesis of irritable bowel syndrome (IBS). Considering that enteric 5-HT is responsible for the secretion, motility and perception of the bowel, the involvement of altered enteric 5-HT metabolism in the pathogenesis of IBS has been elucidated. Higher 5-HT availability is commonly associated with depressed SERT mRNA in patients with IBS compared with healthy controls. The expression difference of SERT between IBS patients and healthy controls might suggest that SERT plays an essential role in IBS pathogenesis, and SERT was expected to be a novel therapeutic target for IBS. Progress in this area has begun to illuminate the complex regulatory mechanisms of SERT in the etiology of IBS. In this article, current insights regarding the regulation of SERT in IBS are provided, including aspects of SERT gene polymorphisms, microRNAs, immunity and inflammation, gut microbiota, growth factors, among others. Potential SERT-directed therapies for IBS are also described. The potential regulators of SERT are of clinical importance and are important for better understanding IBS pathophysiology and therapeutic strategies.


Assuntos
Regulação da Expressão Gênica , Síndrome do Intestino Irritável/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Serotonina/metabolismo , Humanos , Inflamação , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Mucosa Intestinal/patologia , Polimorfismo Genético , RNA Mensageiro/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Transdução de Sinais , Regulação para Cima
7.
Chin Med J (Engl) ; 129(20): 2427-2433, 2016 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-27748334

RESUMO

BACKGROUND: Colorectal serrated polyp is considered as histologically heterogeneous lesions with malignant potential in western countries. However, few Asian studies have investigated the comprehensive clinical features of serrated polyps in symptomatic populations. The aim of the study was to evaluate the features of colorectal serrated polyps in a Chinese symptomatic population. METHODS: Data from all consecutive symptomatic patients were documented from a large colonoscopy database and were analyzed. Chi-square test or Fisher's exact test and logistic regression analysis were used for the data processing. RESULTS: A total of 9191 (31.7%) patients were detected with at least one colorectal polyp. The prevalence of serrated polyps was 0.53% (153/28,981). The proportions of hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), and traditional serrated adenoma (TSA) of all serrated polyps were 41.2%, 7.2%, and 51.6%, respectively, which showed a lower proportion of HP and SSA/P and a higher proportion of TSA. Serrated polyps appeared more in males and elder patients while there was no significant difference in the subtype distribution in gender and age. The proportions of large and proximal serrated polyps were 13.7% (21/153) and 46.4% (71/153), respectively. In total, 98.9% (89/90) serrated adenomas were found with dysplasia. Moreover, 14 patients with serrated polyps were found with synchronous advanced colorectal neoplasia, and large serrated polyps (LSPs) (odds ratio: 3.446, 95% confidence interval: 1.010-11.750, P < 0.05), especially large HPs, might have an association with synchronous advanced neoplasia (AN). CONCLUSIONS: The overall detection rate of colorectal serrated polyps in Chinese symptomatic patient population was low, and distribution pattern of three subtypes is different from previous reports. Moreover, LSPs, especially large HPs, might be associated with an increased risk of synchronous AN.


Assuntos
Neoplasias do Colo/diagnóstico , Neoplasias do Colo/epidemiologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Adulto , Distribuição por Idade , Idoso , Distribuição de Qui-Quadrado , Colonoscopia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência
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