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2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(6): 692-696, 2019 Jun 10.
Artículo en Chino | MEDLINE | ID: mdl-31238621

RESUMEN

Objective: To investigate the clinical characteristics of diabetic patients combined with acute myocardial infarction (AMI) and to compare the prognosis between diabetic and non- diabetic patients in 4-5 years after the onset of AMI. Methods: Followed the certain inclusive and exclusive criteria, a total of 420 patients with acute myocardial infarction were included and divided into diabetes group (group D) and non-diabetes group (group N) with numbers as 161 people and 259 respectively. Baseline data, clinical information, short-term outcome and long-term prognosis of the two groups were compared and analyzed. Results: Among the patients with diabetes, the average age was older (65.65±11.33 vs. 63.30±15.34), with fewer males (64.59% vs. 79.92%); and more likely to have other complications as hypertension (64.60% vs. 53.28%) or hyperlipidemia (42.24% vs. 26.25%). 59.29% of the patients in group D showed pathological changes in 3 major coronary arteries, which were significantly more than its counterpart (40.83%). The proportion of patients that had undergone the coronary artery bypass, grafting (11.11% vs. 5.31%) appeared also higher. There was no significant difference seen in the short-term outcomes between the two groups, but results from the long-term follow-up program showed that both the incidence of Major Adverse Cardiovascular Events (MACE) (50.67% vs. 27.72%) and the all-cause mortality (20.00% vs. 9.90%) in group D were higher than those appeared in group N (27.72%). Conclusions: Patients suffered from the combination of both diabetes and acute myocardial infarction appeared older in age, more in females, with more complications and the coronary artery lesions were more severe and wider. During hospitalization, no significant difference was seen regarding the short-term outcomes between the two groups but the results from long-term follow-up process showing that the risk of MACE events was significantly higher in patients with type2 diabetes.


Asunto(s)
Diabetes Mellitus/epidemiología , Infarto del Miocardio/epidemiología , China/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Pronóstico
3.
J Biol Regul Homeost Agents ; 33(3): 687-694, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31162036

RESUMEN

To investigate the effect of exogenous insulin-like growth factor-1 (IGF-1) on the healing of skin ulcers in diabetic rats, male Sprague Dawleys (SD) rats with back skin ulcers were selected and divided into control group, model group and IGF-1 treatment group which received different doses of IGF-1 (0.5, 1.0, 1.5, and 2.0mg/L). The results showed that the healing speed of the skin ulcers was significantly affected by IGF-1, which reduced the size of wound (P less than 0.05). The expression of MMP-9 was enhanced while the expression of TIMP-1 was decreased in diabetic rats with skin ulcers. The IGF-1 treatment helped to re¬store the normal expression of both MMP-9 and TIMP-1 in diabetic rats with skin ulcers, and diabetic skin ulcers in the 1.5 mg/L IGF-1 group showed the best healing. Histological examination showed that after 20 days, fibroblasts in the IGF-1 experimental group with an appropriate concentration increased and the numbers of fibroblasts and capillaries were significantly higher than those of the other groups. Moreover, there were obvious wound surface contractions and re-epithelialization, and the new epithelium moved to the center of the wound faster. Therefore, it is concluded that an appropriate concentration of IGF-1 can significantly promote the healing of skin ulcers in diabetic rats.


Asunto(s)
Diabetes Mellitus Experimental/patología , Factor I del Crecimiento Similar a la Insulina/farmacología , Úlcera Cutánea/tratamiento farmacológico , Cicatrización de Heridas , Animales , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Ratas , Ratas Sprague-Dawley , Piel , Inhibidor Tisular de Metaloproteinasa-1/metabolismo
4.
Sci Rep ; 9(1): 7828, 2019 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-31127125

RESUMEN

The potential applications of perovskite manganite R1-xAxMnO3 (R = rare earth element; A = Sr, Ca) thin films have been continuously explored due to their multi-functional properties. In particular, the optimally hole-doped La0.67Ca0.33MnO3 thin film demonstrates a colossal magneto-resistance that is beneficial to the performance of spintronic devices. To understand the effect of R and A ions on the material properties, we systematically measure the resistivity, magnetization, and electronic energy states for three optimally hole-doped R0.67A0.33MnO3 thin films with R = La, Sm and A = Sr, Ca. Various energy parameters are derived based on the X-ray absorption and X-ray photoelectron spectra, including the band gap, the charge frustration energy and the magnetic exchange energy. It is interesting to find that the replacement of La with Sm is more effective than that of Sr with Ca in terms of tuning the electrical property, the Curie temperature, and the band gap. The strain-induced reduction of the O 2p- Mn 3d hybridization and the interplay of R/A site disorder and strain effect are discussed. The results of this study provide useful information for the band design of perovskite oxide films.

5.
Sci Rep ; 9(1): 5160, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30914713

RESUMEN

This study probes the temperature-dependent strain that is strongly correlated with the orbital and magnetic structures of epitaxial films of Nd0.35Sr0.65MnO3 (NSMO) that are fabricated by pulsed laser deposition with two thicknesses, 17 (NS17) and 103 nm (NS103) on SrTiO3 (STO) substrate. This investigation is probed using X-ray diffraction (XRD) and absorption-based techniques, X-ray linear dichroism (XLD) and the X-ray magnetic circular dichroism (XMCD). XRD indicates a significant shift in the (004) peak position that is associated with larger strain in NS17 relative to that of NS103 at both 30 and 300 K. Experimental and atomic multiplet simulated temperature-dependent Mn L3,2-edge XLD results reveal that the stronger strain in a thinner NS17 film causes less splitting of Mn 3d eg state at low temperature, indicating an enhancement of orbital fluctuations in the band above the Fermi level. This greater Mn 3d orbital fluctuation can be the cause of both the enhanced ferromagnetism (FM) as a result of spin moments and the reduced Néel temperature of C-type antiferromagnetism (AFM) in NS17, leading to the FM coupling of the canted-antiferromagnetism (FM-cAFM) state in NSMO/STO epitaxial films at low temperature (T = 30 K). These findings are also confirmed by Mn L3,2-edge XMCD measurements.

6.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 53(3): 195-200, 2018 Mar 09.
Artículo en Chino | MEDLINE | ID: mdl-29972979

RESUMEN

Objective: To evaluate the effects of casein phosphopeptide-amorphic calcium phosphate (CPP-ACP) on enamel erosion using an improved in situ experimental protocol. Methods: Forty-eight enamel blocks were prepared from fresh-extracted human premolars and further embedded in the acrylic resins. The present study was divided into 2 parts. In part 1 of the study, two volunteers were recruited to test the availability and safety of the in situ erosion protocol. Customized intraoral appliance was made with 4 reservoirs containing the specimens for each volunteer. For each intraoral applicance, 2 reservoirs were made with the openings and the other 2 remained intact. All volunteers were instructed to drink 150 ml cola within 5 min using the gargling method after placing appliances intraorally for 2 h. After erosion, the appliances were remained undisturbed intraorally for 1 h until the next erosive attack. The in situ erosion cycles were performed 4 times daily over 7 d. In part 2 of the study, forty specimens were randomly divided into 2 groups (n=20): CPP-ACP group and control group. The surfaces of specimens in CPP-ACP group were pretreated with CPP-ACP for 3 min before in situ erosion, whereas the specimens in control group were pretreated with deionized water for 3 min. For each intraoral applicance, 4 reservoirs were made with openings. Ten healthy volunteers were recruited and the above-mentioned in situ erosion protocol was applied to test the effects of CPP-ACP on enamel erosion. The surface microhardness and surface microstructure of the samples were examined before and after erosion in both parts of the study. The data were statistically analyzed using ANOVA and LSD tests. Data were considered statistically significant at a level of P<0.05. Results: Significant surface softening was observed in all specimens after erosion (P<0.001). The surface microhardness in the CPP-ACP group and control group were (198.8±23.2) and (152.4±42.1) HV, respectively (P=0.040). The specimens in the CPP-ACP group showed significantly fewer changes in surface microstructure compared with those in the control group. Conclusions: Based on this in situ experimental protocol, short-time consuming of acid beverages would produce significant effects on the surface microhardness of the human enamel, whereas the application of CPP-ACP can increase the erosion resistance of the enamel.


Asunto(s)
Caseínas/farmacología , Esmalte Dental/efectos de los fármacos , Erosión de los Dientes/prevención & control , Bebidas Gaseosas/efectos adversos , Humanos , Distribución Aleatoria , Erosión de los Dientes/inducido químicamente , Remineralización Dental
7.
Genet Mol Res ; 15(1)2016 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-26909998

RESUMEN

We conducted a case-control study to assess the role of two IL10 gene polymorphisms (rs1800896 and rs1800872) in susceptibility to liver cirrhosis, and their association with chronic hepatitis B in a Chinese population. A case-control study was designed to investigate the association between functional polymorphisms of IL10 (rs1800896 and rs1800872) and the development of liver cirrhosis. Between March 2012 and March 2014, we recruited 241 patients with liver cirrhosis and 254 controls from Xianyang Central Hospital. Genotyping of IL10 rs1800896 and rs1800872 polymorphisms was carried out using the polymerase chain reaction coupled with restriction fragment length polymorphism. Using multivariate logistic regression analysis, we found that individuals with the AA genotype of IL10 rs1800896 showed an increased risk of liver cirrhosis compared with those with the GG genotype in a codominant model (OR = 2.01, 95%CI = 1.10-3.65). In dominant and recessive models, we found that the IL10 rs1800896 polymorphism was correlated with the development of liver cirrhosis (for the dominant model, OR = 1.46, 95%CI = 1.01-2.13; for the recessive model, OR = 1.72, 95%CI = 1.01-3.02). In summary, our study suggests that the IL10 rs1800896 polymorphism is associated with the development of liver cirrhosis.


Asunto(s)
Hepatitis B Crónica/genética , Interleucina-10/genética , Cirrosis Hepática/genética , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad/genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad
8.
Eur Rev Med Pharmacol Sci ; 18(22): 3464-7, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25491622

RESUMEN

OBJECTIVE: To explore the clinical effectiveness of continuous blood purification (CBP) in combination with ulinastatin for the treatment of thermoplegia. PATIENTS AND METHODS: Forty patients (28 men and 12 women) with severe heat stroke were admitted to our hospital's ICU department from June 2010 to August 2013. The patients were randomized into a treatment group (n=21; 15 men and six women, with an average age of 32.9 years) and control group (n=19; 13 men and six women, with an average age of 33.1 years). Patients in the control group underwent treatments of oxygen inhalation, dynamic ECG monitoring, physical cooling methods (ice caps or ice application), whereas patients in the treatment group, in addition to this treatment, were further treated with continuous blood purification in combination with ulinastatin. During administration, the content of one vial was dissolved in 100 mL of physiological saline for intravenous dripping for 1.5 hours. RESULTS: There were 18 cured cases, one case of sequelae of mild neurological disorders, and two deaths in the treatment group, with the cure rate of 90.48%. In comparison, there were 12 cured cases, three cases of sequelae of mild neurological disorders, and four deaths in the control group, with the cure rate of 78.95%. The overall response rates of rectal temperature drop were determined to be 95.24% and 73.68% for the treatment group and the control group, respectively. Based on the treatment outcomes data, multiple organ dysfunction syndrome (MODS) recovery, deaths and survival outcomes of patients in the treatment group was more favorable than that of the control group. This difference was statistically significant (p < 0.05). CONCLUSIONS: Continuous blood purification in combination with ulinastatin is effective in treating thermoplegia and warrants further investigation.


Asunto(s)
Glicoproteínas/administración & dosificación , Golpe de Calor/diagnóstico , Golpe de Calor/terapia , Hemofiltración/métodos , Adulto , Anciano , Terapia Combinada/métodos , Terapia Combinada/tendencias , Femenino , Hemofiltración/tendencias , Hospitalización/tendencias , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
9.
Nat Commun ; 5: 3522, 2014 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-24663109

RESUMEN

The success of semiconductor technology is largely ascribed to controlled impacts of strains and defects on the two-dimensional interfacial charges. Interfacial charges also appear in oxide heterojunctions such as LaAlO3/SrTiO3 and (Nd0.35Sr0.65)MnO3/SrTiO3. How the localized strain field of one-dimensional misfit dislocations, defects resulting from the intrinsic misfit strains, would affect the extended oxide-interfacial charges is intriguing and remains unresolved. Here we show the atomic-scale observation of one-dimensional electron chains formed in (Nd0.35Sr0.65)MnO3/SrTiO3 by the condensation of characteristic two-dimensional interfacial charges into the strain field of periodically arrayed misfit dislocations, using chemical mapping and quantification by scanning transmission electron microscopy. The strain-relaxed inter-dislocation regions are readily charge depleted, otherwise decorated by the pristine charges, and the corresponding total-energy calculations unravel the undocumented charge-reservoir role played by the dislocation-strain field. This two-dimensional-to-one-dimensional electronic condensation represents a novel electronic-inhomogeneity mechanism at oxide interfaces and could stimulate further studies of one-dimensional electron density in oxide heterostructures.

10.
Cell Death Dis ; 4: e793, 2013 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-24008737

RESUMEN

Chronic pulmonary obstructive disease (COPD) is the fourth leading cause of death worldwide, however, the pathogenic factors and mechanisms are not fully understood. Pulmonary emphysema is one of the major components of COPD and is thought to result from oxidative stress, chronic inflammation, protease-antiprotease imbalance and lung epithelial (LE) cell apoptosis. In our previous studies, COPD patients were noted to have higher levels of placenta growth factor (PlGF) in serum and bronchoalveolar lavage fluid than controls. In addition, transgenic mice overexpressing PlGF developed pulmonary emphysema and exposure to PlGF in LE cells induced apoptosis. Furthermore, intratracheal instillation of porcine pancreatic elastase (PPE) on to PlGF wild type mice induced emphysema, but not in PlGF knockout mice. Therefore, we hypothesized that PPE generates pulmonary emphysema through the upregulation of PlGF expression in LE cells. The elevation of PlGF then leads to LE cell apoptosis. In the present study, we investigated whether PPE induces PlGF expression, whether PlGF induces apoptosis and whether the downstream mechanisms of PlGF are related to LE cell apoptosis. We found that PPE increased PlGF secretion and expression both in vivo and in vitro. Moreover, PlGF-induced LE cell apoptosis and PPE-induced emphysema in the mice were mediated by c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) pathways. Given these findings, we suggest that the increase in PlGF and PlGF-induced JNK and p38 MAPK pathways contribute to PPE-induced LE cell apoptosis and emphysema. Regulatory control of PlGF and agents against its downstream signals may be potential therapeutic targets for COPD.


Asunto(s)
Apoptosis , Enfisema/patología , Células Epiteliales/patología , Pulmón/patología , Proteínas Gestacionales/metabolismo , Animales , Apoptosis/efectos de los fármacos , Enfisema/enzimología , Activación Enzimática/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/enzimología , Células Epiteliales/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Páncreas/enzimología , Elastasa Pancreática , Factor de Crecimiento Placentario , Proteínas Gestacionales/farmacología , Sus scrofa , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
11.
Br J Anaesth ; 110(1): 81-6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22986418

RESUMEN

BACKGROUND: Single-breath vital capacity inhalation induction with high concentration sevoflurane (SBVC-HC) is a rapid and 'needleless' technique, preferred and well tolerated in the cooperative child. The addition of nitrous oxide may speed up induction by its second gas effects. Previous studies done in children looking at the effect of N(2)O on this technique lacked power and showed conflicting results. This study aims to investigate the effect of N(2)O on induction time for SBVC-HC sevoflurane induction in children. METHODS: Eighty unpremedicated, ASA I and II children, aged 5-15 yr having elective surgical procedures under general anaesthesia, were recruited and randomized to: Group A: 8% sevoflurane in O(2) 6 litre min(-1), and Group B: 8% sevoflurane in N(2)O 4 litre min(-1) and O(2) 2 litre min(-1). The primary outcome was the time to 'loss of eyelash reflex'. The time to return of 'regular respiration' and 'conjugate gaze' were also noted. RESULTS: The difference in the 'time to loss of eyelash reflex' was small but statistically significant. Group B: mean duration 53.6 s, standard deviation (SD) 16.1, compared with Group A: 63.5 s, SD 16.1 (mean difference 9.9, 95% confidence interval 2.5-17.3, P=0.01). Differences in the time to return of 'regular breathing' and 'conjugate gaze' were not statistically significant. Patients receiving N(2)O had less excitatory movements (P=0.007), but incidence of other adverse events was low and did not differ significantly between both groups. More than 94% of children would choose this method of induction again in both groups. CONCLUSIONS: We conclude that for SBVC-HC sevoflurane induction in children, the addition of N(2)O resulted in faster loss of consciousness and reduced excitatory movements.


Asunto(s)
Anestesia por Inhalación/métodos , Anestésicos por Inhalación/administración & dosificación , Éteres Metílicos/administración & dosificación , Óxido Nitroso/administración & dosificación , Administración por Inhalación , Adolescente , Procedimientos Quirúrgicos Ambulatorios , Presión Arterial/efectos de los fármacos , Presión Arterial/fisiología , Niño , Preescolar , Determinación de Punto Final , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Oxígeno/sangre , Satisfacción del Paciente , Reflejo/efectos de los fármacos , Sevoflurano , Signos Vitales
12.
Oral Dis ; 19(5): 513-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23163860

RESUMEN

OBJECTIVE: Placenta growth factor (PlGF) is associated with the progression and prognosis of oral cancer. MATERIALS AND METHODS: This study used ELISA, quantitative polymerase chain reaction, and Western blotting to study the arecoline-stimulated (PlGF) protein or mRNA expression in human gingival epithelial S-G cells. RESULTS: Arecoline, a major areca nut alkaloid and an oral carcinogen, could stimulate PlGF protein synthesis in S-G cells in a dose- and time-dependent manner. The levels of PlGF protein secretion increased about 3.1- and 3.8-fold after 24-h exposure to 0.4 and 0.8 mM arecoline, respectively. Pretreatment with antioxidant N-acetyl-l-cysteine (NAC) and ERK inhibitor PD98059, but not NF-κB inhibitor Bay 11-7082, JNK inhibitor SP600125, p38 MAPK inhibitor SB203580, and PI3-K inhibitor LY294002, significantly reduced arecoline-induced PlGF protein synthesis. ELISA analyses demonstrated that NAC and PD98059 reduced about 43% and 38% of the arecoline-induced PlGF protein secretion, respectively. However, combined treatment with NAC and PD98059 did not show additive effect. Moreover, 10 µM curcumin and 4 mM NAC significantly inhibited arecoline-induced ERK activation. Furthermore, 10 µM curcumin completely blocked arecoline-induced PlGF mRNA expression. CONCLUSION: Arecoline-induced PlGF synthesis is probably mediated by reactive oxygen species/ERK pathways, and curcumin may be an useful agent in controlling oral carcinogenesis.


Asunto(s)
Arecolina/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Encía/citología , Proteínas Gestacionales/biosíntesis , Arecolina/antagonistas & inhibidores , Células Cultivadas , Curcumina/farmacología , Humanos , Factor de Crecimiento Placentario
13.
Int J Clin Pharmacol Ther ; 49(11): 705-8, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22011697

RESUMEN

The optimal steroid dosages in AECOPD are still under debate. Admission records of patients in our hospital from January to December 2008 due to a diagnosis of AECOPD were reviewed. More wheezing and tachypnea were noted in the patients with a maximal daily prednisolone dose more than 60 mg. The steroid dose was higher in AECOPD without pneumonia than those concurrent with pneumonia. Those who had concurrent pneumonia had a higher risk of nosocomial infections. The study reflects the heterogeneity of AECOPD and that steroid dosages were determined by the clinical evaluation of the severity of illness and bacterial infections.


Asunto(s)
Corticoesteroides/uso terapéutico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Aguda , Humanos , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos
14.
Int J Clin Pharmacol Ther ; 49(1): 49-50, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21176726

RESUMEN

Chemical pleurodesis is an effective treatment for persistent air leakage and secondary pneumothorax. We report the case of a 57-year-old man who presented with pneumothorax and was treated by tube thoracostomy. Because of malpositioning of the chest tube, the minocycline that was administered for pleurodesis was injected into the lung parenchyma instead, which induced chemical pneumonitis. A review of literature indicated that this is the first report of minocycline-associated chemical pneumonitis and its successful treatment.


Asunto(s)
Antibacterianos/efectos adversos , Minociclina/efectos adversos , Neumonía/inducido químicamente , Tubos Torácicos , Humanos , Masculino , Persona de Mediana Edad , Neumonía/diagnóstico por imagen , Neumonía/terapia , Radiografía Torácica
15.
Oral Dis ; 15(8): 602-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19619196

RESUMEN

OBJECTIVE: To investigate the incidence and risk factors of post-tooth extraction sepsis in patients without locoregional infection. SUBJECTS AND METHODS: We assessed all claim records of the Taiwanese National Health Insurance program in 2005. Admissions for patients aged > or =16 years containing a discharge diagnosis of sepsis, and who received tooth extraction within 14 days before the admission were identified. Patient charts were reviewed to confirm the diagnosis of sepsis and rule out other infection sources. The relationship between postextraction sepsis (PES) and clinical parameters was analyzed. RESULTS: Thirty-three of the 2 223 971 extraction cases met the criteria of PES, an incidence of 1.48 per 100 000, and seven patients (21.2%) died of the disease. Aging significantly increased the risk of PES (P < 0.001). Pre-existing comorbidities were found in 20 of the 33 cases, with diabetes mellitus and hematologic diseases the most common. The method, number, and position of extraction had no influence on PES incidence. Blood cultures were positive in 25 patients (75.8%) and isolates included species of the Streptococcus, Actinomyces, Klebsiella, Bacteroides, Prevotella, and Enterococcus genera. CONCLUSION: Tooth extraction is associated with a low but significant risk of postoperative sepsis, especially in the elderly and patients with underlying diseases.


Asunto(s)
Infección Focal Dental/epidemiología , Complicaciones Posoperatorias/epidemiología , Sepsis/epidemiología , Extracción Dental/efectos adversos , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Infección de la Herida Quirúrgica/epidemiología , Taiwán/epidemiología , Extracción Dental/estadística & datos numéricos , Adulto Joven
16.
Ultramicroscopy ; 108(10): 1200-4, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18571855

RESUMEN

We report here the successful fabrication of large-area size-tunable periodic arrays of cobalt and Co-silicide nanodots on silicon substrates by employing the colloidal nanosphere lithography (NSL) technique and heat treatments. The growth of low-resistivity epitaxial CoSi(2) was found to be more favorable for the samples with smaller Co nanodot sizes. The sizes of the epitaxial CoSi(2) nanodots can be tuned from 50 to 100 nm by varying the diameter of the colloidal spheres and annealing temperatures. The epitaxial CoSi(2) nanodots were found to grow with an epitaxial orientation with respect to the (001)Si substrates: [001]CoSi(2)//[001]Si and (200)CoSi(2)//(400)Si. From the results of planview HRTEM, XTEM, and SAED analysis, the epitaxial CoSi(2) nanodots were identified to be inverse pyramids in shape, and the average sizes of the faceted silicide nanodots were measured to decrease with annealing temperature. The observed results present the exciting prospect that with appropriate controls, the colloidal NSL technique promises to facilitate the growth of a variety of well-ordered silicide nanodots with selected shape, size, and periodicity.

17.
Thorax ; 63(6): 500-6, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18202163

RESUMEN

BACKGROUND: Vascular endothelial growth factor (VEGF) and its receptor may have an important role in the pathogenesis of emphysema. The effect of another angiogenic factor, placenta growth factor (PlGF), in chronic obstructive pulmonary disease (COPD) is unknown. METHODS: The serum levels of VEGF and PlGF in patients with COPD (n = 184), smokers (n = 212) and non-smokers (n = 159) and the bronchoalveolar lavage (BAL) fluid levels of VEGF and PlGF in another group (20 patients with COPD, 18 controls) were measured. In vitro cell culture experiments were performed to investigate the effect of PlGF on VEGF. RESULTS: The mean (SE) serum levels of PlGF were significantly higher in patients with COPD than in controls (27.1 (7.4) pg/ml vs 12.3 (5.1) pg/ml in smokers and 10.8 (6.3) pg/ml in non-smokers, p = 0.005). The levels of PlGF in BAL fluid were also significantly higher in patients with COPD than in controls (45.7 (12.3) pg/ml vs 23.9 (7.6) pg/ml, p = 0.005), associated with an increase in the cytokines tumour necrosis factor-alpha (TNF-alpha) and interleukin-8 (IL-8). In patients with COPD the levels of PlGF correlated inversely with forced expiratory volume in 1 s (FEV(1)) in serum (r = -0.59, p = 0.002) and in BAL fluid (r = -0.51, p = 0.001). While the serum levels of VEGF were the same in patients with COPD and controls, the BAL fluid levels were significantly lower in patients with COPD than in controls (127.5 (30.1) pg/ml vs 237.8 (36.1) pg/ml, p = 0.002). In cultured bronchial epithelial cells, proinflammatory cytokines induced an increase in the protein expression of both PlGF and VEGF. Continuous concomitant treatment with PlGF, TNF-alpha and IL-8 stimulation reduced VEGF expression and induced cell death. This phenomenon was suppressed by VEGF receptor inhibitor (CBO-P11). CONCLUSIONS: The serum and BAL fluid levels of PlGF are increased in patients with COPD and are inversely correlated with FEV(1). Concomitant treatment with PlGF, TNF-alpha and IL-8 causes detrimental effects on airway epithelial cells. These data suggest that bronchial epithelial cells can express PlGF, which may contribute to the pathogenesis of COPD.


Asunto(s)
Proteínas Gestacionales/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Anciano , Líquido del Lavado Bronquioalveolar/química , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Interleucina-8/metabolismo , Masculino , Factor de Crecimiento Placentario , Fumar/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Capacidad Vital/fisiología
18.
Int J Tuberc Lung Dis ; 11(12): 1290-5, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18034948

RESUMEN

BACKGROUND: Transient worsening of tuberculosis (TB) symptoms and lesions following anti-tuberculosis treatment (paradoxical response [PR]), has been described in human immunodeficiency virus (HIV) infected patients who undergo anti-tuberculosis treatment. The frequency and clinical presentations for PR in HIV-negative patients with pulmonary TB are unknown. OBJECTIVE: To determine the incidence of PR and its associated manifestations in a retrospective study of HIV-negative patients with pulmonary TB. RESULTS: Of 659 TB patients, 16 developed PR, with an incidence of 2.4%. The medium onset time of PR was 26 days. Recurrent fever was the most common clinical manifestation. Compared with 643 patients without PR, patients developing PR had significantly decreased haemoglobin, albumin, body mass index and baseline lymphocyte counts. There was a noticeable increase in the lymphocyte count during paradoxical deterioration in PR subjects than in the control group. Independent factors for developing PR included anaemia, hypoalbuminaemia, lymphopaenia and lymphocyte count increase during PR development. CONCLUSIONS: The clinical manifestations of PR in patients with pulmonary TB were different from those in patients with extra-pulmonary TB. Baseline anaemia, hypoalbuminaemia, lymphopaenia and a greater change in lymphocyte count were independent risk factors for developing PR.


Asunto(s)
Antituberculosos/uso terapéutico , Seronegatividad para VIH , Tuberculosis Pulmonar/tratamiento farmacológico , Distribución de Chi-Cuadrado , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
19.
Eur Respir J ; 23(6): 818-24, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15218992

RESUMEN

Genetic susceptibility to the development of chronic obstructive pulmonary disease (COPD) might depend on variation in the activities of enzymes that detoxify cigarette smoke products, such as microsomal epoxide hydrolase (mEPHX) and glutathione S-transferase (GST). It was investigated whether polymorphisms in these genes had any association with susceptibility to COPD and COPD severity. The genotypes of 184 patients with COPD and 212 control subjects were determined by polymerase chain reaction followed by restriction fragment length polymorphism analysis of the mEPHX, GSTM1, GSTT1 and GSTP1 genes. All subjects were smokers or exsmokers. The proportion of GSTM1-null genotypes was significantly higher in patients with COPD than in control subjects (61.4 versus 42.5%). No differences were observed in the frequency of polymorphic genotypes for mEPHX, GSTT1 and GSTP1. During combined analysis of genetic polymorphisms for mEPHX, GSTM1 and GSTP1, it was found that there are strong indicators for susceptibility to COPD (genotype combination with at least one mutant mEPHX exon-3 allele (histidine 113), GSTM1 null and homozygous for the GSTPI isoleucine 105 allele). The frequencies of homozygous mutant alleles of mEPHX exon 3 and the GSTMI-null genotype were significantly higher in patients with severe COPD (forced expiratory volume in one second of <35% of the predicted value). It is proposed that the combination of genetic variants including at least one mutant microsomal epoxide hydrolase exon-3 allele and glutathione S-transferase M1-null and homozygous isoleucine 105 glutathione S-transferase P1 genotypes are significant indicators of susceptibility to chronic obstructive pulmonary disease in the Taiwanese population. In addition, the homozygous variant of microsomal epoxide hydrolase exon 3 and the glutathione S-transferase M1-null genotype are independent risk factors for developing severe chronic obstructive pulmonary disease.


Asunto(s)
Epóxido Hidrolasas/genética , Glutatión Transferasa/genética , Polimorfismo Genético , Enfermedad Pulmonar Obstructiva Crónica/enzimología , Enfermedad Pulmonar Obstructiva Crónica/genética , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Oportunidad Relativa , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Fumar/efectos adversos , Taiwán
20.
Ultramicroscopy ; 98(2-4): 265-9, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15046807

RESUMEN

Apparent growth of amorphous layers during low temperature annealing was observed in low energy Ge(+)-implanted (001)Si by high-resolution transmission electron microscopy. The occurrence of abnormal growth is due to the randomization of heavily damaged regions beneath the original amorphous/crystalline interfaces. The randomization process is attributed to the strain, incurred by the presence of a high density of large Ge atoms in the heavily damaged Si substrate, relaxation to lower the free energy of the systems. The randomization upon annealing may be fruitfully applied to minimize the transient enhanced diffusion in shallow junction formation.

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