Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Acta Crystallogr C Struct Chem ; 79(Pt 2): 36-42, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36739608

RESUMEN

Two binary cocrystals of 1,4-diiodotetrafluorobenzene (1,4-DITFB, C6F4I2) and 1,3,5-trifluoro-2,4,6-triiodobenzene (1,3,5-TITFB, C6F3I3) with the flexible 2-{[(naphthalen-2-yl)methyl]sulfanyl}pyridine 1-oxide (NTPO, C16H13NOS) molecule were successfully prepared and characterized by X-ray diffraction and quantum chemistry calculation methods. X-ray diffraction analysis reveals that the conformation of the flexible NTPO molecule has been changed significantly after introducing the 1,4-DITFB or 1,3,5-TITFB molecule into the NTPO lattice. Also the formation of the binary cocrystals is driven mainly by robust C-I...-O-N+ halogen bonds and π-hole...π-bond interactions, and they possess `sandwich' structural frameworks. Moreover, interaction energy analysis and AIM analysis were used to explore the contribution of different fragments to the structural stability and the corresponding electronic properties, which reveals that the robust halogen bonds with shorter bonding lengths [2.768 (4) and 2.789 (3) Å] are suggested to be covalent to a certain degree.

2.
Animals (Basel) ; 12(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35565572

RESUMEN

Kudoa (Myxosporea: Multivalvulida) parasites are critical pathogens in marine and freshwater fish associated with significant economic losses and reduced market prices caused by post-mortem myoliquefaction or numerous cysts on muscles. In the present study, large yellow croakers infected by Kudoa were found during fish disease surveillance in China in November 2020 and used for morphological observation and characterization using light DIC microscopy and electron microscopy. Numerous creamy-white oval plasmodia were observed in muscles and on the surface of brain cartilage, gill arches, and serosal surfaces. The spores were considerably longer and thicker than previously reported Kudoa, with protruding polar filaments (PFs) in the mature spores, fingertip-shaped apical projections (APs), and polar capsules. Phylogenetic analyses with SSU rDNA, LSU rDNA, and mitochondrial DNA showed that the Kudoa-infected sample (LcK-2020) had the highest similarity to Kudoa iwatai reported in Japan. Based on the morphological characterization and phylogenetic analysis, it could be concluded that the sample LcK-2020 was infected by Kudoa iwatai, which would be the first report of Kudoa iwatai infection in large yellow croaker in China.

3.
Front Psychol ; 13: 793483, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35360560

RESUMEN

Student-teacher relationships (STRs) have been examined by many studies. However, an omission still exists, the existing scales are not appropriate for studying STRs in private colleges because of the special character of these schools. This paper presents the development and validation of Private-College Student-Teacher Relationship Scale (PCSTRS), the first instrument to evaluate student-teacher relationships (STRs) in private colleges. The PCSTRS has six dimensions: trust, interaction, intimacy, care, approval, and comfort. In our main study, the validity and reliability of the six-factor PCSTRS model were demonstrated. The result of internal consistency coefficient indicated the high reliability of the scale, and the result of concurrent validity indicated the significant correlational relationships between the PCSTRS with other STR measures. In supplementary study, the PCSTRS was administered to 360 participants to confirm the applicability of PCSTRS and investigate the relation of STRs and students' traits, performance, and wellbeing, as well as the differences between the private school and the public school in this relation; the analyses revealed that there were significant differences in trust, intimacy, and care between private and public colleges; positive correlations were found between STRs and self-esteem, self-efficacy, academic performance, extracurricular activity involvement, and subjective wellbeing. Present research firstly develops the PCSTRS, examined the reliability and validity, and provides the proposed nomological network among related constructs.

4.
Chemistry ; 28(2): e202103336, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34791726

RESUMEN

Rapid capture of 129 I with high volatility and toxicity in the environment has attracted much attention. Herein we reported a firstly synthesized nonporous material: pyridine N-oxides (NTPO and ATPO) as iodine adsorbent. Both of NTPO and ATPO exhibit remarkable performance on the adsorption of iodine in aqueous solution, vapor state and organic solvents. Upon the capture of iodine, pyridine N-oxides were transformed to binary cocrystals combined with the pyridine N-oxides and iodine which is driven by halogen bond between iodine and oxygen atoms. Moreover, pyridine N-oxides shows high chemical, thermal and moisture stability.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117428, 2020 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-31376727

RESUMEN

Room temperature phosphorescence (RTP) materials have become a hot topic in fields of organic light-emitting dioes, biological sensing and imaging. The present work reports firstly that 1,3,5-trifluoro-2,4,6-triiodobenzene (TITFB) can act as a simple pure organic NIR phosphor due to its novel function in promoting n-π∗ transition. Also, TITFB crystal has longer phosphorescence lifetime than other ordinary multiiodoluminophors and TITFB powder. Based on the TITFB crystal structure, σ-hole and π-hole capture mechanism of n-electron is proposed, i.e., the excited state energy is decreased and n-electrons are stabilized to cause slower radiative decay rate due to the restriction of σ-hole and π-hole bond. Both computational and experimental studies support the mechanism. The new electron-capture mode is more conducive to understanding pure organic ultralong lifetime RTP.

6.
Jpn J Radiol ; 37(10): 701-709, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31401722

RESUMEN

OBJECTIVES: To evaluate quantitative three-dimensional (3D) dynamic contrast-enhanced ultrasound (DCE-US) in the assessment of tumor angiogenesis using an orthotropic liver tumor model. METHODS: Nine New Zealand white rabbits with liver orthotropic VX2 tumors were established and imaged by two-dimensional (2D) and 3D DCE-US after SonoVue® bolus injections. The intraclass correlation coefficients of perfusion parameters, including peak intensity (PI), mean transit time, time to peak, and area under the curve, were calculated based on time-intensity curve. The percentage area of microvascular (PAMV) and the expression of vascular endothelial growth factor (VEGF) were both evaluated by immunohistochemical analysis and weighted by the tumor activity area ratio. Correlations between quantitative and histologic parameters were analyzed. RESULTS: The reproducibility of 3D DCE-US quantitative parameters was excellent (ICC 0.91-0.99); but only PI showed high reproducibility (ICC 0.97) in 2D. None of the parameters of quantitative 2D DCE-US were significantly correlated with weighted PAMV or VEGF. For 3D DCE-US, there was a positive correlation between PI and weighted PAMV (r = 0.74, P = 0.04) as well as VEGF (r = 0.79, P = 0.02). CONCLUSION: Quantitative parameters of 3D DCE-US show feasibility, higher reproducibility and accuracy for the assessment of tumor angiogenesis using an orthotropic liver tumor model compared with 2D DCE-US.


Asunto(s)
Medios de Contraste , Aumento de la Imagen/métodos , Imagenología Tridimensional/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Neovascularización Patológica/diagnóstico por imagen , Ultrasonografía/métodos , Animales , Modelos Animales de Enfermedad , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Neoplasias Hepáticas/patología , Neovascularización Patológica/patología , Conejos , Reproducibilidad de los Resultados
7.
Dig Dis Sci ; 61(9): 2522-34, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27146412

RESUMEN

BACKGROUND/AIM: Obstructive jaundice (OJ) is frequently complicated by infections and has been associated with increased bacterial translocation, intestinal epithelial hyperpermeability, and oxidative stress, but the mechanism remains unclear. The potential effect of resveratrol (Res) on modifying intestinal epithelial dysfunction was evaluated both in vitro and in vivo. METHODS: Caco-2 cells (in vitro) and male Wistar rats (n = 60; in vivo) were used to evaluate the role of Res on intestinal epithelial dysfunction. Hydrogen peroxide was used to induce oxidative stress in the Caco-2 cells. In bile duct-ligated group, OJ was successfully established on Day 7 after bile duct ligation, whereas sham-operated and vehicle-treated rats served as controls. Western blot and RT-qPCR were performed to analyze TJ proteins expression in epithelium isolated from rat intestine. RESULTS: Intestinal hyperpermeability was associated with decreased expression and phosphorylation of occludin and zonula occluden (ZO-1), but increased oxidation in Caco-2 cells and the intestinal epithelium. Res treatment increased the epithelial expression and phosphorylation of occludin and ZO-1 in a concentration-dependent manner. Moreover, Res which protected Caco-2 cells from H2O2-induced oxidative damage clearly reduced malondialdehyde level and intracellular reactive oxygen species accumulation, but increased the expression levels of superoxide dismutase and heme oxygenase-1 (HO-1). Further studies showed that Res also inhibited H2O2-induced protein kinase C activity and p38 phosphorylation. Interestingly, these effects of Res were abolished by the HO-1 inhibitor zinc protoporphyrin or knockdown of HO-1 by siRNA. CONCLUSIONS: Res protected gut barrier function possibly by initiating HO-1-dependent signaling which is essential for common expression of key tight junction proteins. It also provides a rationale to develop Res clinical applications of intestinal disorders.


Asunto(s)
Antioxidantes/farmacología , Hemo-Oxigenasa 1/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Ictericia Obstructiva/genética , Estrés Oxidativo/efectos de los fármacos , Estilbenos/farmacología , Uniones Estrechas/efectos de los fármacos , Animales , Conductos Biliares/cirugía , Western Blotting , Células CACO-2 , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Técnicas In Vitro , Mucosa Intestinal/metabolismo , Ictericia Obstructiva/metabolismo , Ligadura , Masculino , Malondialdehído/metabolismo , Ocludina/efectos de los fármacos , Ocludina/metabolismo , Permeabilidad/efectos de los fármacos , Fosforilación/efectos de los fármacos , Proteína Quinasa C/efectos de los fármacos , Proteína Quinasa C/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Resveratrol , Uniones Estrechas/metabolismo , Regulación hacia Arriba , Proteína de la Zonula Occludens-1/efectos de los fármacos , Proteína de la Zonula Occludens-1/metabolismo
8.
Zhonghua Zhong Liu Za Zhi ; 34(6): 446-9, 2012 Jun.
Artículo en Chino | MEDLINE | ID: mdl-22967447

RESUMEN

OBJECTIVE: To evaluate the H. pylori and Epstein-Barr virus infection in cardiac and distal gastric adenocarcinoma tissues in residents in Cixian county, a high risk area of esophageal cancer in Hebei province, and to explore the putative role of H. pylori and Epstein-Barr virus infection in the carcinogenesis of adenocarcinoma at different subsites of stomach. METHODS: H. pylori and Epstein-Barr virus latent membrane protein 1 (EBV-LMP1) immunopositivities were determined by Elivision(TM) plus immunohistochemical staining in 190 gastric adenocarcinoma tissues including 144 cases of cardiac adenocarcinoma and 46 cases of distal gastric adenocarcinoma. The relationship between H. pylori and Epstein-Barr virus infection and the subsite, Laurén type as well as other clinicopathological features of gastric adenocarcinoma were analyzed. RESULTS: No significant difference was found between the H. pylori detection rates in cardiac and distal gastric adenocarcinomas(56.9% vs. 65.2%, P > 0.05). The detection rate of H. pylori in intestinal type was significantly higher than that in the diffuse type distal gastric adenocarcinomas (71.8% vs. 28.6%, P < 0.05). No positive expression of EBV-LMP1 was found in the gastric adenocarcinomas in this study. CONCLUSIONS: No significant differences in H. pylori and EBV-LMP1 infections were found between cardiac and distal gastric adenocarcinomas in Cixian county. H. pylori infection is related with the intestinal type of distal gastric adenocarcinoma.


Asunto(s)
Adenocarcinoma , Cardias , Infecciones por Virus de Epstein-Barr/patología , Infecciones por Helicobacter/patología , Neoplasias Gástricas , Adenocarcinoma/microbiología , Adenocarcinoma/patología , Adenocarcinoma/virología , Anciano , China , Femenino , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Neoplasias Gástricas/virología , Proteínas de la Matriz Viral/metabolismo
9.
Zhonghua Zhong Liu Za Zhi ; 32(9): 671-5, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-21122381

RESUMEN

OBJECTIVE: To study the possible role of JNK1, Raf-1 and Livin in the carcinogenesis of sporadic colorectal tubular adenoma. METHODS: Immunohistochemical staining was used to detect the expression of JNK1, Raf-1 and Livin proteins in 65 sporadic colorectal tubular adenomas with dysplasia of varying degrees and 22 colorectal tubular adenoma with cancerous area. RESULTS: In normal colorectal mucosa, colorectal tubular adenoma with dysplasia and colorectal tubular adenoma with cancerous area, the positive rate of JNK1, Raf-1 and Livin expression was increased gradually. The positive expression of JNK1, Raf-1 and Livin was all significantly higher in the cases of colorectal tubular adenoma with dysplasia or with cancerous area than that in normal colorectal mucosa (P < 0.05), and the positive expression of JNK1, Raf-1 and Livin was significantly higher in colorectal tubular adenoma with cancerous area than that in colorectal tubular adenoma with dysplasia of different degrees (P < 0.05). In the cases of colorectal tubular adenoma with dysplasia of varying degrees, the positive expression of Raf-1 was increased along with the increasing dysplasia degree of colorectal tubular adenoma (P < 0.05). Coexpression of JNK1, Raf-1 and Livin increased gradually in the carcinogenesis of sporadic colorectal tubular adenoma, while positive correlation was found among the expressions of JNK1, Raf-1 and Livin. CONCLUSION: JNK1, Raf-1 and Livin may be involved in the carcinogenesis of sporadic colorectal tubular adenoma.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adenoma/patología , Transformación Celular Neoplásica , Neoplasias Colorrectales/patología , Proteínas Inhibidoras de la Apoptosis/metabolismo , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogénicas c-raf/metabolismo , Adenoma/metabolismo , Adulto , Carcinoma/metabolismo , Carcinoma/patología , Neoplasias Colorrectales/metabolismo , Femenino , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patología
10.
Zhonghua Zhong Liu Za Zhi ; 29(7): 514-7, 2007 Jul.
Artículo en Chino | MEDLINE | ID: mdl-18069631

RESUMEN

OBJECTIVE: To investigate the possible role of STAT3 and p38 in the carcinogenesis of sporadic colorectal tubular adenoma. METHODS: The expression of STAT3 and p38 at protein level was studied in 107 sporadic colorectal tubular adenomas with different dysplasia (SCTA-D) or with cancerous changes (SCTA-Ca) by immunohistochemical staining method, meanwhile the expression of STAT3 at mRNA level was detected by in situ hybridization. RESULTS: Immunohistochemical staining results showed that the positive expression rate of STAT3 and p38 was 12.0%, 59.0%, 91.7% and 8.0%, 47.0%, 91.7% in normal colorectal mucosa (NCM), SCTA-D and SCTA-Ca, respectively, with a statistically significant difference of STAT3 and p38 expression among the SCTA-D, SCTA-Ca and NCM (P < 0.05). The expression of STAT3 and p38 was positively correlated with the degree of dysplasia from mild to severe SCTA-D (P < 0.05). In situ hybridization results showed that the positive expression rate of STAT3 at mRNA level in NCM, SCTA-D and SCTA-Ca was 8.00%, 51.8% and 100.0%, respectively, with a statistically significant difference among these either (P < 0.05). The positive expression of STAT3 at mRNA level was not only positively correlated with the degree of dysplasia (P < 0.05), but also with the expression of p38 (P < 0.05). CONCLUSION: STAT3 and p38 may be involved in the carcinogenesis of sporadic colorectal tubular adenoma.


Asunto(s)
Adenoma/metabolismo , Neoplasias Colorrectales/metabolismo , Lesiones Precancerosas/metabolismo , Factor de Transcripción STAT3/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adenoma/patología , Transformación Celular Neoplásica/metabolismo , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , Humanos , Mucosa Intestinal/metabolismo , Lesiones Precancerosas/patología , ARN Mensajero/metabolismo , Factor de Transcripción STAT3/genética , Proteínas Quinasas p38 Activadas por Mitógenos/genética
11.
Gynecol Oncol ; 103(1): 226-33, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16631235

RESUMEN

OBJECTIVES: Chemokine CXCL12 and its unique receptor CXCR4 have been recently implicated in cancer metastasis. Our goal was to explore expression of CXCL12 and CXCR4 protein in normal ovarian surface epithelium, primary tumors and paired metastases of epithelial ovarian cancer as well as its association with clinicopathological features. We also wanted to test if expression of CXCR4 has prognostic value in epithelial ovarian cancer patients. METHOD: Sections from 6 normal ovarian surface epithelium, 44 primary epithelial ovarian tumors and 30 paired metastatic tumors in omentum were evaluated for CXCL12 and CXCR4 expression using immunohistochemistry (IHC). RESULTS: All samples of normal ovarian surface epithelium were negative for CXCL12 and CXCR4 protein. Ovarian cancer cells mainly showed cytoplasmic staining of CXCL12 and CXCR4. CXCL12 and CXCR4 staining were detected in 40/44 (91%) and 26/44 (59%) patients with primary epithelial ovarian tumors respectively. CXCR4 expression in primary tumors had no significant correlation with lymph nodes metastasis. However, if we combined CXCR4 expression in primary tumors with metastatic tumors, a significant correlation with lymph nodes metastasis was found (P = 0.018). The intensity of CXCL12 staining correlated with ascites (P = 0.014). The rate of CXCR4 expression in refractory and recurrent group (81% versus 28%, P = 0.0008) was significantly higher than that in no-recurrent group. After a median follow-up of 37 months, CXCR4 expression was found associated with an unfavorable prognosis with significantly reduced median disease progression-free survival and overall survival of 15 and 27 months (P = 0.0004, P = 0.017) respectively. Median time-to-event was not reached in patients with negative CXCR4 staining. In multivariate analysis, CXCR4 expression and residual tumor size emerged as independent prognostic factors in epithelial ovarian cancer patients. CONCLUSIONS: This article provides the first evidence that CXCR4 expression could be an independent prognostic factor for epithelial ovarian cancer patients.


Asunto(s)
Quimiocinas CXC/biosíntesis , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/patología , Receptores CXCR4/biosíntesis , Adulto , Anciano , Quimiocina CXCL12 , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Células Epiteliales/patología , Femenino , Humanos , Persona de Mediana Edad , Tasa de Supervivencia
12.
Zhonghua Zhong Liu Za Zhi ; 25(4): 372-5, 2003 Jul.
Artículo en Chino | MEDLINE | ID: mdl-12921570

RESUMEN

OBJECTIVE: To study the expression of EP-CAM, beta-catenin in the carcinogenesis of squamous cell carcinoma of uterine cervix. METHODS: The expressions of EP-CAM and beta-catenin were detected with immunohistochemical stain in 14 cases of normal cervical squamous epithelium, 32 cases of cervical intraepithelial neoplasia (CIN) and 38 cases of cervical invasive squamous cell carcinoma. RESULTS: The over-expression rates of EP-CAM were 0, 7.1%, 20.0%, 62.5% and 55.3% for normal cervical epithelium, CINI, CINII, CINIII and carcinoma groups. The EP-CAM over-expression rates in CINIII and cervical carcinoma groups were significantly higher than those in normal epithelium and CINI groups (P < 0.001). No aberrant expression of beta-catenin was shown in normal cervical epithelium, while the aberrant expression rates of beta-catenin in CINI, CINII, CINIII and cervical carcinoma group were 28.6%, 40.0%, 62.5% and 84.2%. The aberrant expression rate of beta-catenin increased with the increase in degree of CIN and development of cervical carcinoma. The over-expression rate of EP-CAM was reversely related to the differentiation of cervical squamous cell carcinoma (P < 0.001). CONCLUSION: EP-CAM and beta-catenin may be involved in the carcinogenesis of squamous cell carcinoma of uterine cervix. The over-expression of EP-CAM and aberrant expression of beta-catenin may serve as markers of squamous carcinogenesis of uterine cervix.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Moléculas de Adhesión Celular/metabolismo , Proteínas del Citoesqueleto/metabolismo , Transactivadores/metabolismo , Displasia del Cuello del Útero/metabolismo , Neoplasias del Cuello Uterino/metabolismo , Biomarcadores de Tumor , Cadherinas/metabolismo , Cuello del Útero/citología , Cuello del Útero/metabolismo , Progresión de la Enfermedad , Células Epiteliales/metabolismo , Epitelio/metabolismo , Femenino , Humanos , beta Catenina
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...