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1.
Molecules ; 29(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38542919

RESUMEN

To improve the mess-specific activity of Co supported on zeolite catalysts in Fischer-Tropsch (FT) synthesis, the Co-MCM-22 catalyst was prepared by simply grinding the MCM-22 with nanosized Co3O4 prefabricated by the thermal decomposition of the Co(II)-glycine complex. It is found that this novel strategy is effective for improving the mess-specific activity of Co catalysts in FT synthesis compared to the impregnation method. Moreover, the ion exchange and calcination sequence of MCM-22 has a significant influence on the dispersion, particle size distribution, and reduction degree of Co. The Co-MCM-22 prepared by the physical grinding of prefabricated Co3O4 and H+-type MCM-22 without a further calcination process exhibits a moderate interaction between Co3O4 and MCM-22, which results in the higher reduction degree, higher dispersion, and higher mess-specific activity of Co. Thus, the newly developed method is more controllable and promising for the synthesis of metal-supported catalysts.

2.
Front Psychol ; 13: 764638, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35369176

RESUMEN

Objective: Investigating the mental health status of Chinese resident physicians during the 2019 new coronavirus outbreak. Methods: A cluster sampling method was adopted to collect all China-wide resident physicians during the epidemic period as the research subjects. The Symptom Checklist-90 self-rating scale was used to assess mental health using WeChat electronic questionnaires. Results: In total, 511 electronic questionnaires were recovered, all of which were valid. The negative psychological detection rate was 93.9% (480/511). Among the symptoms on the self-rating scale, more than half of the Chinese resident physicians had mild to moderate symptoms of mental unhealthiness, and a few had asymptomatic or severe unhealthy mental states. In particular, the detection rate of abnormality was 88.3% (451/511), obsessive-compulsive symptoms was 90.4% (462/511), the sensitive interpersonal relationship was 90.6% (463/511), depression abnormality was 90.8% (464)/511), anxiety abnormality was 88.3% (451/511), hostility abnormality was 85.3% (436/511), terror abnormality was 84.9% (434/511), paranoia abnormality was 86.9% (444/511), psychotic abnormalities was 89.0% (455/511), and abnormal sleeping and eating status was 90.8% (464/511). The scores of various psychological symptoms of pediatric resident physicians were significantly lower than those of non-pediatrics (p < 0.05). Conclusion: The new coronavirus epidemic has a greater impact on the mental health of Chinese resident physicians.

3.
Front Mol Biosci ; 8: 725308, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34651015

RESUMEN

With the development of high-throughput sequencing technology, the posttranscriptional mechanism of alternative splicing is becoming better understood. From decades of studies, alternative splicing has been shown to occur in multiple tissues, including the brain, heart, testis, skeletal muscle, and liver. This regulatory mechanism plays an important role in physiological functions in most liver diseases. Currently, due to the absence of symptoms, chronic pediatric liver diseases have a significant impact on public health. Furthermore, the progression of the disease is accelerated in children, leading to severe damage to their liver tissue if no precautions are taken. To this end, this review article summarizes the current knowledge of alternative splicing in pediatric liver diseases, paying special attention to liver damage in the child stage. The discussion of the regulatory role of splicing in liver diseases and its potential as a new therapeutic target is also included.

4.
Front Mol Biosci ; 8: 696319, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34568424

RESUMEN

As a pivotal regulator of 5' splice site recognition, U1 small nuclear ribonucleoprotein (U1 snRNP)-specific protein C (U1C) regulates pre-mRNA splicing by interacting with other components of the U1 snRNP complex. Previous studies have shown that U1 snRNP and its components are linked to a variety of diseases, including cancer. However, the phylogenetic relationships and expression profiles of U1C have not been studied systematically. To this end, we identified a total of 110 animal U1C genes and compared them to homologues from yeast and plants. Bioinformatics analysis shows that the structure and function of U1C proteins is relatively conserved and is found in multiple copies in a few members of the U1C gene family. Furthermore, the expression patterns reveal that U1Cs have potential roles in cancer progression and human development. In summary, our study presents a comprehensive overview of the animal U1C gene family, which can provide fundamental data and potential cues for further research in deciphering the molecular function of this splicing regulator.

5.
Sci Rep ; 11(1): 12760, 2021 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-34140531

RESUMEN

Eukaryotic cells can expand their coding ability by using their splicing machinery, spliceosome, to process precursor mRNA (pre-mRNA) into mature messenger RNA. The mega-macromolecular spliceosome contains multiple subcomplexes, referred to as small nuclear ribonucleoproteins (snRNPs). Among these, U1 snRNP and its central component, U1-70K, are crucial for splice site recognition during early spliceosome assembly. The human U1-70K has been linked to several types of human autoimmune and neurodegenerative diseases. However, its phylogenetic relationship has been seldom reported. To this end, we carried out a systemic analysis of 95 animal U1-70K genes and compare these proteins to their yeast and plant counterparts. Analysis of their gene and protein structures, expression patterns and splicing conservation suggest that animal U1-70Ks are conserved in their molecular function, and may play essential role in cancers and juvenile development. In particular, animal U1-70Ks display unique characteristics of single copy number and a splicing isoform with truncated C-terminal, suggesting the specific role of these U1-70Ks in animal kingdom. In summary, our results provide phylogenetic overview of U1-70K gene family in vertebrates. In silico analyses conducted in this work will act as a reference for future functional studies of this crucial U1 splicing factor in animal kingdom.


Asunto(s)
Filogenia , Ribonucleoproteína Nuclear Pequeña U1/genética , Secuencia de Aminoácidos , Animales , Eucariontes/genética , Perfilación de la Expresión Génica , Humanos , Unión Proteica , Dominios Proteicos , Factores de Empalme de ARN/genética , Factores de Empalme de ARN/metabolismo , ARN Mensajero/metabolismo , Ribonucleoproteína Nuclear Pequeña U1/química , Ribonucleoproteína Nuclear Pequeña U1/metabolismo , Homología de Secuencia de Aminoácido
6.
World J Gastroenterol ; 25(12): 1513-1523, 2019 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-30948914

RESUMEN

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is currently the outstanding cause of chronic liver disease in children and adolescents, especially in overweight and obese groups. Liver biopsy is the reference standard to diagnose NAFLD but invasive, thus it is not the best choice in clinical diagnosis and follow-up. Magnetic resonance (MR) is widely used in clinical trials to noninvasively quantify liver fat content in adults and children in foreign countries. While currently, it is rarely used in Chinese children and adolescents. We postulated that quantifying hepatic steatosis by MR could be extended to children and adolescents in China. AIM: To investigate the accuracy of MR imaging (MRI) in quantifying liver fat with MR spectroscopy (MRS) as a reference. A secondary goal was to assess the prevalence of NAFLD in overweight and obese Chinese children and adolescents. METHODS: There were 86 children and adolescents enrolled in this study, including 65 overweight and obese children and 21 healthy children. The participants underwent MRI and MRS. MRI and MRS were performed using multi-echo Dixon and HISTO sequences, respectively, to calculate hepatic proton density fat fraction (PDFF). Hepatic steatosis was diagnosed using MRS-PDFF > 5% as the threshold. Spearman's analysis was used to evaluate the correlation between MRI and MRS. The agreement between these two methods was assessed by Bland-Altman analysis. RESULTS: The MRI-PDFF in the MRS region of interest and the entire liver was 9.9% ± 10.3% with a range of 0.3%-39.9%, and 10.6% ± 9.4% with a range of 1.9%-38.9%, respectively. The MRS-PDFF was 9.1% ± 10.0%, with a range of 0.5%-37.8%. The incidence of hepatic steatosis detected by MRS-PDFF was 46.5% (40/86) of all participants, all of whom belonged to the overweight and obese group. Spearman's analysis indicated an excellent correlation between multi-echo Dixon and MRS (r > 0.9, P < 0.01). Bland-Altman analysis also demonstrated a good agreement between these two methods. CONCLUSION: Multi-echo Dixon shows an excellent correlation and agreement with MRS in quantifying liver fat content and could be a potential tool to detect hepatic steatosis in Chinese children and adolescents.


Asunto(s)
Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Sobrepeso/complicaciones , Adolescente , Biopsia , Niño , China/epidemiología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Hígado/patología , Masculino , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/patología , Prevalencia
7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 40(3): 378-384, 2018 Jun 28.
Artículo en Chino | MEDLINE | ID: mdl-29978796

RESUMEN

Objective To investigate the role of 17-MHz high-frequency linear array probe in detecting the microcalcification of papillary thyroid carcinoma (PTC) and its pathological basis. Methods The clinical data of 75 patients with PTC diagnosed by ultrasonography and pathology in China-Japan Friendship Hospital from January 2016 to January 2017 were analyzed. The detection rate of microcalcification was compared between 17-MHz high-frequency ultrasound and conventional ultrasound,and the imaging findings and pathological Results were analyzed. Results Among 93 thyroid nodules,the detection rate of PTC microcalcification by 17-MHz ultrasound was 74.2% (69/93),which was significantly higher than that of conventional ultrasound (59.1%,55/93) (χ2=4.742,P=0.029). The diagnostic sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of the conventional ultrasound and the 17-MHz ultrasound were 73.6% and 98.1%,60.0% and 57.5%,67.7% and 80.6%,70.9% and 75.4%,and 63.1% and 95.8%,respectively. Pathology confirmed the presence of microcalcification at 53 nodules,among which psammoma bodies were found in 10 nodules;in addition,all the psammoma bodies were located in the cell mass,whereas irregular calcium deposits were mainly in proliferated fibrous tissues. Conclusion sThe 17-MHz high-frequency ultrasound can increase the detection rate of microcalcification in thyroid nodules. The ultrasonic manifestations of microcalcification do not completely correspond to the psammoma bodies found in pathology;rather,they may represent the irregular calcium deposits on fibrous tissues.


Asunto(s)
Calcinosis/diagnóstico por imagen , Cáncer Papilar Tiroideo/diagnóstico por imagen , Neoplasias de la Tiroides/diagnóstico por imagen , Ultrasonografía , Humanos , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Nódulo Tiroideo/diagnóstico por imagen
8.
J Clin Ultrasound ; 44(6): 347-53, 2016 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-26890486

RESUMEN

PURPOSE: To evaluate the diagnostic efficacy of virtual touch tissue quantification (VTQ) and contrast-enhanced ultrasonography (CEUS), separately and in combination, in diagnosing malignant focal liver lesions (FLLs). METHODS: Forty-six patients with 55 FLLs (28 benign and 27 malignant) underwent both VTQ and CEUS. The diagnostic values of VTQ and CEUS, alone and in combination, were compared. RESULTS: The diagnostic sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of CEUS were 92.6% (25/27), 96.4% (27/28), 94.5% (52/55), 96.2% (25/26), and 93.1% (27/29), respectively. The diagnostic sensitivity, specificity, accuracy, PPV, and NPV of VTQ with a cutoff of 2.22 m/s were 51.9% (14/27), 85.7% (24/28), 69.1% (38/55), 77.8% (14/18), and 64.9% (24/37), respectively. The diagnostic sensitivity, specificity, accuracy, PPV, and NPV of VTQ and CEUS combined were 96.3% (26/27), 82.1% (23/28), 89.1% (49/55), 83.9% (26/31), and 95.8% (23/24), respectively. Comparing the accuracies of the three methods, the diagnostic values of CEUS and of the combination of CEUS with VTQ were significantly higher than those of VTQ alone (p ≤ 0.01). There was no significant difference between the combination of CEUS with VTQ and CEUS (p = 0.49). CONCLUSIONS: CEUS is superior to VTQ in diagnosing malignant FLLs. Adding VTQ to CEUS did not improve the diagnosis of FLLs. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:347-353, 2016.


Asunto(s)
Medios de Contraste , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Ultrasonografía/métodos , Diagnóstico Diferencial , Femenino , Humanos , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Pathobiology ; 76(4): 163-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19571605

RESUMEN

BACKGROUND: Genes involved in the TGF-beta signaling pathway are often altered in several types of cancers. The TGF-beta-resistant human colon cancer cell line HT-29 has inactivated TbetaRII and deficient expression of RUNX3 and Smad4, which are involved in the TGF-beta signaling pathway. METHODS: Western blot and immunocytochemistry were performed to confirm gene expression, the MTT assay to detect cell growth, flow cytometry to investigate the cell cycle and the TUNEL to detect cell apoptosis. RESULTS: In the absence of TGF-beta, Bim was upregulated, cell growth was inhibited and apoptosis was induced. TGF-beta treatment did not affect RUNX3 expression; however, the increase in Bim expression was significant and time dependent. Interestingly, Smad4 but not Smad2/3 was also upregulated upon exposure to TGF-beta. This was not the case after TGF-beta treatment of parent HT-29 cells. As expected, TGF-beta further inhibited cell growth and induced apoptosis in HT-29/RUNX3+ cells. CONCLUSION: Our data demonstrate that RUNX3 is involved in TGF-beta-dependent and -independent cell growth inhibition and apoptosis induction pathways.


Asunto(s)
Neoplasias del Colon/genética , Neoplasias del Colon/patología , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 3 del Factor de Unión al Sitio Principal/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Transducción de Señal , Proteína Smad4/metabolismo
10.
Zhonghua Zhong Liu Za Zhi ; 30(3): 170-3, 2008 Mar.
Artículo en Chino | MEDLINE | ID: mdl-18756929

RESUMEN

OBJECTIVE: To evaluate the anti-angiogenic activity of peptide 21 obtained by modification of tumstatin, and its inhibitory effect on the growth and metastasis of human ovarian cancer transplanted in nude mice. METHODS: The peptide 21 was purified by affinity chromatography. Human ovarian cancer SKOV3 cells were inoculated in nude mice and the transplanted tumor was treated with the peptide 21 to observe the tumor growth and metastasis. The microvessel density (MVD) and immunohistochemical staining index of PCNA, VEGF and MMP-2 and TIMP-2 were performed to assess the inhibitory effect of the peptide 21. RESULTS: In the nude mice at 21 days after peptide 21 treatment, the inhibition rate of tumor growth was 53.17%, the tumor microvessel density was significantly reduced (P <0.05), the expression of PCNA, VEGF and MMP-2 were significantly lower (P <0.01), and TIMP-2 expression was significantly higher (P <0.01) in comparison with that of control group. CONCLUSION: The peptide 21 generated in this study has a significant anti-angiogenetic activity, showing significant inhibitory effect on the growth of human ovarian cancer transplanted in nude mice. The mechanism of its inhibitory action on ovarian cancer growth may be mediated by reduction of neovascularization and reduction of expression of angiogenetic factors.


Asunto(s)
Autoantígenos/farmacología , Colágeno Tipo IV/farmacología , Neovascularización Patológica/prevención & control , Neoplasias Ováricas/patología , Péptidos/farmacología , Carga Tumoral/efectos de los fármacos , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/farmacología , Animales , Antígenos CD34/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacología , Autoantígenos/química , Línea Celular Tumoral , Colágeno Tipo IV/química , Femenino , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Neovascularización Patológica/patología , Neoplasias Ováricas/metabolismo , Péptidos/química , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Mol Cell Biochem ; 309(1-2): 117-23, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18008140

RESUMEN

Tumor suppressor p53 plays important roles in cell cycle regulation, apoptosis and DNA repair in different cell types including lung cancer. There are different p53 apoptotic pathways in high and low metastatic ability lung cancer cells. However, the exactly mechanism in the pathway is still unclear. Here we found that Annexin A2, a Ca2+ -dependent phospholipid-binding protein, is involved in p53-mediated apoptosis. First, by using mRNA differential display technique, down-regulated Annexin A2 expression was found in all cell lines transfected of Ad-p53 (adenoviral expression construct encoding wild type p53 gene) especially in highly metastatic Anip973 lung cancer cells. Then, decreased expression of Annexin A2 was further confirmed by Northern blot and Western blot analysis. At last, knock down of Annexin A2 by siRNA inhibited cellular proliferation in BE1 cell line with highly metastatic ability. Taken together, our results suggested that Annexin A2 may play roles in p53 induced apoptosis and it is also involved in regulation of cell proliferation.


Asunto(s)
Anexina A2/metabolismo , Apoptosis , Neoplasias Pulmonares/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Adenoviridae , Infecciones por Adenoviridae , Anexina A2/genética , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Metástasis de la Neoplasia
12.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 23(3): 231-2, 2005 Jun.
Artículo en Chino | MEDLINE | ID: mdl-16078465

RESUMEN

OBJECTIVE: To discuss the unsuccessful reasons and the preventive methods of the unsuccessful clinic cases. METHODS: The retrospective analysis was carried on the 80 prosthesis in 70 patients from 1994 to 2001 which were suffered with unsuccessful results after the restoration of the metal crowns and bridges. RESULTS: There were 68 teeth which had collapsed or broken. 20 teeth had the post loosing or shedding. Root breaking, food impaction, unharmony colors of porcelain and the changing color of gingival were 3, 3, 6 and 2 teeth. CONCLUSION: It is necessary to select suitable repairing materials and operate correctly for preventing the occurring of the unsuccessful results in the porcelain-fused-to-metal-crowns and bridges.


Asunto(s)
Coronas , Porcelana Dental , Humanos , Metales , Diente Molar , Estudios Retrospectivos , Raíz del Diente
13.
Zhonghua Nan Ke Xue ; 8(2): 125-6, 2002.
Artículo en Chino | MEDLINE | ID: mdl-12479028

RESUMEN

OBJECTIVES: To evaluate the effects of varicocele (VC) on IL-1 and NO levels in testes of rats with VC. METHODS: Male adult Wistar rats were divided into two groups randomly, VC group (n = 30) and pseudo-operation group (n = 20), and the levels of IL-1 and NO in the testes were determined and compared. RESULTS: The levels of IL-1 and No of left tests in VC group were higher than those in pseudo-operation group, respectively(P < 0.01). While the levels of IL-1 and NO of right testes between two groups were not significantly different (P > 0.05). More over, the level of IL-1 correlated significantly with that of NO(r = 0.572, P < 0.01). CONCLUSIONS: The results revealed that the changes of IL-1 and NO levels in the testes of rats with VC might be the reason which caused testes damage, disturbance of spermatogenesis and even infertility.


Asunto(s)
Interleucina-1/metabolismo , Óxido Nítrico/metabolismo , Testículo/metabolismo , Varicocele/metabolismo , Animales , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas Wistar , Testículo/ultraestructura
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