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1.
J Phys Condens Matter ; 33(11): 115702, 2020 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-33316790

RESUMEN

Charge distribution on every atom of carbon matter in four dimension forms (cluster, fullerene, atomistic carbon chain, nanotube, graphene, surface and solid) was investigated by the first-principles calculation. It is found that the charge distribution in most of these materials is inhomogeneous, even in one certain solid phase. We found that if one atom in carbon has different surrounding environment from another one nearby, they always have electron transfer, that is, they have different charge. In round C10 ring, C24 and C60 fullerenes, charge is zero, while charge is not zero in pentagon C10 ring, C30 and C70 fullerenes. At the ends of atomistic chains, nanotube or on the edges of graphenes, carbon atoms have larger positive or negative charge, while almost zero in the central parts. Charge is zero in diamond and graphite, while it is not zero in the high pressure solid phase hexagonite or on some carbon surfaces. The non-zero charge in carbon possibly means its non-zero valence.

2.
Eur Rev Med Pharmacol Sci ; 23(18): 7884-7891, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31599450

RESUMEN

OBJECTIVE: MiR-199 expression is associated with liver cancer. Bioinformatics analysis revealed that miR-199 has a complementary binding site to the 3'-UTR region of Snail mRNA. This study investigated whether miR-199 plays a role in regulating Snail expression and affecting epithelial-mesenchymal transition (EMT) and invasion of hepatoma cells. PATIENTS AND METHODS: The Dual-Luciferase reporter gene assay validated the targeted regulation between miR-199 and Snail. QRT-PCR was used to detect and compare the expression of miR-199 and Snail mRNA in human normal liver HL7702 cells, low metastatic MHCC97L cells, and high metastatic MHCC97H cells. MHCC97H cells were cultured in vitro and divided into two groups: miR-NC group and the miR-199 mimic group followed by the analysis of the expression of Snail, E-cadherin, and N-cadherin, as well as cell invasion ability by transwell assay. RESULTS: There was a targeted regulatory relationship between miR-199 and Snail mRNA. Compared with HL7702 cells, miR-199 expression was significantly decreased, and Snail expression was significantly increased in MHCC97L and MHCC97H cells, with more changes being observed in high metastatic MHCC97H cells. The transfection of miR-199 mimic significantly downregulated the expression of Snail and N-cadherin in MHCC97H cells, increased E-cadherin expression, inhibited the cell's EMT process, and invasion. CONCLUSIONS: The decrease of miR-199 expression plays a role in upregulating the expression of Snail and promoting EMT and invasion of hepatocarcinoma cells. The increase of the expression of miR-199 can inhibit the expression of Snail and inhibit the EMT process and invasion ability of hepatoma cells.


Asunto(s)
Transición Epitelial-Mesenquimal/efectos de los fármacos , Neoplasias Hepáticas/patología , MicroARNs/farmacología , Regiones no Traducidas 3'/genética , Cadherinas/metabolismo , Carcinoma Hepatocelular/genética , Estudios de Casos y Controles , Línea Celular Tumoral/metabolismo , Línea Celular Tumoral/patología , China/epidemiología , Biología Computacional/métodos , Regulación hacia Abajo , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , MicroARNs/genética , Invasividad Neoplásica/genética , Factores de Transcripción de la Familia Snail/genética , Regulación hacia Arriba
3.
Zhonghua Er Ke Za Zhi ; 56(3): 200-205, 2018 Mar 02.
Artículo en Chino | MEDLINE | ID: mdl-29518830

RESUMEN

Objective: To understand the outcome of asthma in children from urban area of Beijing and the factors associated with the outcome. Methods: A total of 497 children with asthma diagnosed in the epidemiological survey of childhood asthma in urban area of Beijing in 2010 were selected in this study. Telephone follow-up was conducted in 2016 to obtain information about asthma attack, emergency visit, hospitalization, medication and disease control, and data of comorbidities of allergic diseases from 1 year earlier. Enumeration data were compared using chi-square test, measurement data were compared by rank sum test. The multi-factor logistic regression analysis was employed for the relationship between the related factors and asthma, Kaplan-Meier survival analysis and COX regression was employed to understand the relationship between the related factors and the course of the disease. Results: Questionnaires were conducted in 366 children, of whom 66.7% (244/366) were male, and 33.3% (122/366) were female.Compared with 2010, the rate of asthma attack and emergency room visits in children in last 12 months were significantly lower (19.1%(70/366) vs. 57.1%(284/497), and 3.0% (11/366) vs.19.7% (98/497), χ(2)=125.910 and 53.352, both P<0.01). There was no significant change in the proportion of allergic rhinitis and atopic dermatitis in last 12 months compared with that 6 years ago (both P>0.05). The number of children with clinical remission (2 years and above) was 75.4% (276/366). The number of children without remission within 2 years was 24.6% (90/366). The majority of children without remission were less than 12 years old boys (52.4% (33/63) vs. 30.9% (56/181) , χ(2)=9.273, P<0.01) . The proportion of children without remission associated with allergic rhinitis (67.8%(61/90)), atopic dermatitis (30.0%(27/90)), first-degree relatives with asthma (68.9%(62/90)) was higher than that of children with remission (51.8%(143/276), 17.0%(47/276), and 54.7%(151/276), respectively, χ(2)=7.013, 7.079, 5.608, respectively, all P<0.05). The proportion of children without remission who used control drugs was (33.3%(30/90)), which was higher than that in children with remission (7.2%(20/276), χ(2)=39.158, P<0.01). Multiple logistic regression showed that boy (OR=2.402 (1.611-3.580), P<0.05), later onset (OR=4.339 (>3-6 years old vs. 0-3 years old), OR=2.630(>6 years old vs. 0-3 years old), χ(2)=18.512, 31.371, 6.510, all P<0.05) were independent risk factors for asthma remission. COX regression analysis showed that the use of control drugs (HR=0.705 (0.515-0.964), χ(2)=4.795, P<0.05) was the relevant factor in the course of the disease. Conclusions: With the increase of age, the incidence of asthma in children in Beijing city in recent 12 months reduced. Male and late onsets were independent risk factors for asthma remission. The use of control drugs was the relevant factor in the course of the disease.


Asunto(s)
Asma , Hospitalización , Asma/complicaciones , Asma/terapia , Beijing , Niño , Ciudades , Comorbilidad , Dermatitis Atópica , Eccema , Femenino , Estudios de Seguimiento , Humanos , Hipersensibilidad , Incidencia , Masculino , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Población Urbana
4.
Eur Rev Med Pharmacol Sci ; 19(10): 1749-53, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26044215

RESUMEN

A patient had right upper quadrant pain with sclera was transferred from emergency room to the hospital, she was proposed to have acute cholecystitis, gallstones, obstructive jaundice, and a four-year history of gallbladder stones. The NMR results showed that the gallbladder was significantly enlarged and the gallbladder wall was thickening irregularly. The liver morphology was not abnormal except with extensive intrahepatic bile duct dilatation. The MRCP results demonstrated that the intrahepatic bile ducts were significant expanded. The ERCP results showed that duodenal stenosis and extra-hepatic bile duct stenosis. We placed a plastic stent of 8.5Fr and 12 cm in length in the hepatic duct, and after biliary plastic stent placement, jaundice was rapidly reduced and liver function was improved significantly. A surgery was performed and the final pathologic diagnosis is a complication of Xanthogranulomatous cholecystitis with Mirizzi syndrome. After the surgery of cholecystectomy and a bile duct repair were performed, the patient was recovered well. Conclusively, if a patient was diagnosed as biliary stricture, a biliary metal stent should not be placed until pathological diagnosis of malignancy.


Asunto(s)
Colecistitis/complicaciones , Colecistitis/diagnóstico , Granuloma/complicaciones , Granuloma/diagnóstico , Síndrome de Mirizzi/complicaciones , Síndrome de Mirizzi/diagnóstico , Xantomatosis/complicaciones , Xantomatosis/diagnóstico , Anciano , Colecistitis/cirugía , Femenino , Granuloma/cirugía , Humanos , Síndrome de Mirizzi/cirugía , Xantomatosis/cirugía
5.
Neotrop Entomol ; 44(1): 68-76, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26013014

RESUMEN

Holcocerus hippophaecolus Hua et al (Lepidoptera: Cossidae) is an important boring pest that damages the sea buckthorn Hippophae rhamnoides. Larvae of H. hippophaecolus cause major losses of this shrub in Northern China, with severe economic and ecological consequences. In this study, we used scanning electron microscopy to investigate the typology, morphology, and distribution of sensilla on the antennae and ovipositor of H. hippophaecolus. In total, seven subtypes of sensilla were found on the antennae, i.e., chaetica, trichodea (two subtypes), basiconica (two subtypes), coeloconica, and Böhm bristles. In addition, three types of sensilla were detected on the ovipositor, i.e., chaetica, trichodea, and basiconica. The identification of these sensilla types could provide morphological evidence to facilitate a better understanding of the host location, mate finding, and oviposition processes of this important species.


Asunto(s)
Mariposas Nocturnas/anatomía & histología , Sensilos , Animales , Femenino , Masculino , Microscopía Electrónica de Rastreo , Oviposición
6.
Oecologia ; 152(2): 307-22, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17479298

RESUMEN

We continuously monitored CO(2) concentrations at three locations along an urban-to-rural gradient in the Salt Lake Valley, Utah from 2004 to 2006. The results showed a range of CO(2) concentrations from daily averages exceeding 500 p.p.m. at the city center to much lower concentrations in a non-urbanized, rural region of the valley. The highest values were measured in the wintertime and under stable atmospheric conditions. At all three sites, we utilized weekly measurements of the C and O isotope composition of CO(2) for a 1-year period to evaluate the CO(2) sources underlying spatial and temporal variability in CO(2) concentrations. The results of an inverse analysis of CO(2) sources and the O isotope composition of ecosystem respiration (delta(18) O (R)) showed large contributions (>50%) of natural gas combustion to atmospheric CO(2) in the wintertime, particularly at the city center, and large contributions (>60%) of biogenic respiration to atmospheric CO(2) during the growing season, particularly at the rural site. delta(18) O (R) was most enriched at the rural site and more isotopically depleted at the urban sites due to the effects of irrigation on ecosystem water pools at the urban sites. The results also suggested differences in the role of leaf versus soil respiration between the two urban sites, with seasonal variation in the contribution of leaf respiration at a residential site and relatively constant contributions of leaf respiration at the city center. These results illustrate that spatial and temporal patterns of urban CO(2) concentrations and isotopic composition can be used to infer patterns of energy use by urban residents as well as plant and soil processes in urban areas.


Asunto(s)
Contaminantes Atmosféricos/química , Dióxido de Carbono/química , Ecosistema , Isótopos de Carbono/química , Actividades Humanas , Consumo de Oxígeno , Plantas/metabolismo , Población Rural , Población Urbana , Utah , Emisiones de Vehículos , Agua/química , Contaminantes Químicos del Agua/química
7.
Brain Res ; 681(1-2): 65-74, 1995 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-7552293

RESUMEN

The a beta peptide is a neurotoxic peptide that accumulates in the brains of Alzheimer patients, but is also present in body fluids at subnanomolar levels. The potential effects of these low levels of a beta are unclear. We now show that one such action is to increase tyrosine phosphorylation in PC12 cells and olfactory neuroblasts. Application of a beta 25-35 or a beta 1-40 induces a dose-dependent increase in the tyrosine phosphorylation in both whole cells and in vitro. The increase in tyrosine phosphorylation is both rapid and sensitive, being stimulated by picomolar doses of a beta and occurring within 1 min of application. Calcium imaging experiments provide further support for the role of tyrosine phosphorylation in the action of a beta. While a beta does not alter calcium metabolism under basal conditions, the addition of a beta induces a rapid increase in cytoplasmic calcium in olfactory neuroblasts that have been treated with the tyrosine phosphatase inhibitor, sodium orthovanadate or in PC12 cells treated with nerve growth factor. These responses could be blocked by the tyrosine kinase inhibitor, herbimycin. These calcium responses displayed an obligate requirement for the presence of matrix proteins. The identification of a rapid, sensitive assay for the action of a beta may facilitate investigations of its mechanism of action.


Asunto(s)
Péptidos beta-Amiloides/farmacología , Calcio/metabolismo , Citosol/metabolismo , Tirosina/metabolismo , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Citosol/efectos de los fármacos , Colorantes Fluorescentes , Fura-2 , Immunoblotting , Cinética , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Bulbo Olfatorio/citología , Bulbo Olfatorio/efectos de los fármacos , Bulbo Olfatorio/metabolismo , Células PC12 , Fosforilación , Pruebas de Precipitina , Ratas
8.
Zhonghua Wai Ke Za Zhi ; 30(12): 710-2, 777, 1992 Dec.
Artículo en Chino | MEDLINE | ID: mdl-1339739

RESUMEN

Immunoregulatory function of peripheral blood monocytes was studied in 20 patients with colorectal cancer, by assaying interleukin 1 (IL-1) and prostaglandin E2 (PGE2) in the culture supernatant of lipopolysaccharide-stimulated monocytes. The results showed that IL-1 activity of the monocyte culture supernatant was decreased in the preoperative patients, compared with that of controls or postoperative groups; the PGE2 content of the culture supernatant of monocytes from the preoperative cases was increased, compared to normal controls or to the postoperative groups. Again, we found that there was significant negative correlation between IL-1 activity and the PGE2 content, with the activity of IL-1 the lowest and the content of PGE2 the highest in advanced colonic cancer patients.


Asunto(s)
Neoplasias del Colon/inmunología , Dinoprostona/metabolismo , Interleucina-1/inmunología , Monocitos/metabolismo , Neoplasias del Recto/inmunología , Adulto , Anciano , Escherichia coli , Femenino , Humanos , Interleucina-1/metabolismo , Lipopolisacáridos , Masculino , Persona de Mediana Edad
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