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1.
Zhonghua Yan Ke Za Zhi ; 60(8): 674-679, 2024 Aug 11.
Artículo en Chino | MEDLINE | ID: mdl-39085157

RESUMEN

Objective: To explore the corrective effects of a personalized corneal refractive surgery design that retains mild myopia in patients over 40 years old with refractive errors and presbyopia. Methods: A retrospective case series study was conducted, including 60 patients (120 eyes) over 40 years old who underwent corneal refractive surgery at Peking Union Medical College Hospital l from January 2023 to December 2023. The patients were divided into two groups based on their preference: Group A (retained mild myopia) and Group B (fully corrected), with 30 patients (60 eyes) in each group. Preoperative and postoperative visual acuity, subjective refraction, slit-lamp examination, corneal topography, and intraocular pressure were assessed at 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months after surgery. The effectiveness and safety indices were calculated based on visual acuity before and after surgery. The National Eye Institute Refractive Quality of Life questionnaire was used to evaluate patient satisfaction and postoperative visual symptoms. Results: There were no significant differences in preoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent (SE), corneal thickness, and intraocular pressure between the two groups (all P>0.05). At the final follow-up, the proportions of eyes with UDVA≥0.8 and≥1.0 were 93.3% (56/60) and 60.0% (36/60) in Group A, and 100% (60/60) and 83.3% (50/60) in Group B, respectively. The SE was significantly different between Group A [(-0.35±0.52) D] and Group B [(-0.07±0.55) D] (P<0.05). Near visual acuity was better in Group A than in Group B (P<0.05). The effectiveness indices were 0.96±0.23 and 0.99±0.12, and the safety indices were 1.02±0.11 and 1.02±0.07 for Groups A and B, respectively. Both groups had high overall satisfaction, but Group A had higher scores for near vision, reading, and computer screen viewing. Conclusion: The personalized corneal refractive surgery design that retains mild myopia provides good corrective effects for patients over 40 years old with refractive errors, improving patient satisfaction and quality of life.


Asunto(s)
Miopía , Presbiopía , Refracción Ocular , Agudeza Visual , Humanos , Presbiopía/cirugía , Estudios Retrospectivos , Miopía/cirugía , Adulto , Calidad de Vida , Satisfacción del Paciente , Córnea/cirugía , Resultado del Tratamiento , Masculino , Femenino , Procedimientos Quirúrgicos Refractivos/métodos , Topografía de la Córnea , Persona de Mediana Edad
2.
Int J Cosmet Sci ; 41(4): 398-404, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31194883

RESUMEN

BACKGROUND: Lactic acid sting test (LAST) is a classical method to identify sensitive skin. However, some subjects with self-perceived sensitive skin are negative for LAST. OBJECTIVE: To determine whether LAST scores are associated with specific phenotype of sensitive skin. METHODS: A total of 292 subjects with self-perceived sensitive skin were enrolled in this study. The Sensitive Scale was used to evaluate the severity of burning, stinging, itching, tautness, erythema and scaling based on 0-10 scale scores. In addition to the assessment of LAST scores, epidermal biophysical properties were measured using an MPA system. RESULTS: The Sensitive Scale scores of stinging, itching, tautness and scaling were significantly different between the LAST-positive and -negative groups. However, burning and erythema scores did not differ between the LAST-positive and -negative groups. LAST scores were positively correlated with the Sensitive Scale scores for stinging, itching, tautness and scaling, but not for burning and erythema scores. Moreover, LAST scores negatively correlated with stratum corneum hydration, but positively with transepidermal water loss (TEWL) rates. CONCLUSIONS: Lactic acid sting test scores positively correlated with TEWL rates. LAST scores could be used to identify subjects with sensitive skin characterized mainly by stinging and itching, but not those mainly by burning and erythema.


CONTEXTE: Le test de la piqûre d'acide lactique (LAST) est une méthode classique pour identifier les peaux sensibles. Cependant, certaines personnes s'évaluant ayant une peau sensible sont négatifs au test LAST. OBJECTIF: Déterminer si le score du LAST est associé à un phénotype spécifique de peau sensible. MÉTHODES: Au total, 292 personnes s'évaluant ayant une peau sensible ont été inclus dans cette étude. L'échelle de sensibilité a été utilisée pour évaluer la sévérité de la brûlure, du picotements, de la démangeaison, de la tension, de l'érythème et des desquamations basée sur une échelle de 0-10. En plus de l'évaluation du score LAST, les propriétés biophysiques épidermiques ont été mesurées à l'aide d'un système MPA. RÉSULTATS: Les scores de l'échelle de sensibilité pour le picotement, les démangeaisons, la tension et la desquamation étaient significativement différents entre la groupe LAST positif et celle du LAST négatif. Cependant, les scores de la brûlure et de l'érythème n'étaient pas différents entre les deux groupes. Le score LAST était positivement corrélé avec les scores de l'échelle de sensibilité du picotement, des démangeaisons, de la tension et des desquamations, mais pas pour la brûlure et l'érythème. En plus, les scores LAST étaient négativement corrélés avec l'hydratation du stratum corneum, mais positivement corrélés avec le taux de perte en eau transépidermique (TEWL). CONCLUSIONS: Les scores LAST étaient corrélés positivement avec le taux de perte en eau transépidermique. Les scores LAST pourraient être utilisés pour identifier les personnes avec la peau sensible caractérisée principalement le picotement et les démangeaisons, mais pas la brûlure et l'érythème.


Asunto(s)
Ácido Láctico/administración & dosificación , Piel/efectos de los fármacos , Adolescente , Adulto , Anciano , Fenómenos Biofísicos , China , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven
3.
Zhonghua Xue Ye Xue Za Zhi ; 40(7): 561-567, 2019 Jul 14.
Artículo en Chino | MEDLINE | ID: mdl-32397018

RESUMEN

Objective: To evaluate the clinical characteristics of T-cell acute leukemia/lymphoma (T-ALL) and explore the prognosis significance of early T-cell precursor leukemia/lymphoma. Methods: A cohort of 126 patients diagnosed with T-ALL from 2008 to 2014 in West China Hospital, Sichuan University were enrolled in this study. They were further categorized by immunophenotype according to the expression of T-cell lineage markers CD1a, CD8, CD5 and one or more stem cell or myeloid markers. The laboratory indicators and prognosis factors were also statistically analyzed. Results: Of all patients, the ratio of male to female was 2.5∶1, with the median age of 25 years old (range 14 to 77) . The percentage of ETP-ALL was up to 47.6%. T-ALL patients showed higher ratio in first clinical remission rate (CR(1)) than T-LBL ones (64.4% vs 30.8%, P=0.032) . Group with WBC count higher than 50×10(9)/L at presentation showed higher ration of achieving CR(1) than those lower than 50×10(9)/L (78.4% vs 50.9%, P=0.010) . In comparison with the non-ETP-ALL, ETP-ALL patients had older age of onset (P<0.001) , lower WBC count (P<0.001) , lower risk of CNS involvement (10.0% vs 30.2%, P=0.009) and slightly inferior overall survival (P=0.073) . T-cell lineage markers CD1a(-), CD8(-) and CD4(-) positive patients had higher CR(1) than their corresponding negative ones (P=0.002, P=0.000, P=0.001) , while CD33(-) and CD56(-) positive patients had lower ratio of achieving CR(1) than their negative ones, respectively (P=0.035, P=0.035) . Conclusion: Flow cytometry and associated markers for immunophenotyping was of significance in the diagnosis and prognosis monitoring of T-ALL/LBL. The percentage of ETP-ALL/LBL subtype was high in Chinese adolescent and adult T-ALL patients. ETP-ALL/LBL was a high risk subtype, which needs more precise standard for diagnosis and advanced therapies for better outcome.


Asunto(s)
Células Precursoras de Linfocitos T/citología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/diagnóstico , Adolescente , Adulto , Anciano , China , Femenino , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células T Precursoras/clasificación , Pronóstico , Adulto Joven
4.
Sci Rep ; 7(1): 15641, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29142278

RESUMEN

This study investigates the effects of restricted grazing time on forage selectivity and meat fatty acid deposition of lambs compared to a traditional grazing system. Results showed that the animals preferred to graze pasture species that were more palatable and lower in fibre, while demonstrating a partial preference for species with high protein levels. Leymus chinensis was more preferentially selected by lambs grazing pasture for shorter periods than longer periods. Lambs that grazed for 4 h per day had a high LNA (α-linolenic acid) intake. The accumulation of LNA and its elongation products in tissue was closely related to the LNA level in diet. Therefore, allowing lambs to graze for at least 4 h per day resulted in a meat fatty acid profile that is richer in health-promoting fatty acids. In particular, the highest DHA (docosahexaenoic acid) was observed in meat from lambs which grazed pasture for 4-h versus 8- and 12-h. It can be concluded that, in grassland systems, a healthier meat fatty acid profile for humans and the potential for better pasture management is achieved by limiting the grazing of lambs to 4 h per day rather than grazing over longer time periods.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Ácidos Grasos Omega-3/metabolismo , Ovinos/metabolismo , Crianza de Animales Domésticos , Animales , Dieta , Carne , Ácido alfa-Linolénico/metabolismo
5.
J Biol Regul Homeost Agents ; 31(3): 615-624, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28952293

RESUMEN

The molecular mechanisms underlying regulation of vascular endothelial growth factor (VEGF) in epithelial ovarian cancer (EOC) remain poorly defined. VEGF, a potent angiogenic factor, is up-regulated in a variety of cancers and contributes to angiogenesis in tumor tissues. The level of VEGF correlates with progression of malignancy. We previously reported that miR-92 is abnormally elevated in the plasma of EOC patients. Here, we tested the hypothesis that miR-92 inhibits von Hippel-Lindau gene product (VHL), a tumor suppressor gene, and in turn de-represses HIF-1α, a known key transcription factor for VEGF, to stimulate VEGF expression. Using a variety of biomedical methods including Western blot, RT-PCR, gene silencing, luciferase assay, and chromatin immunoprecipitation in both surgically-resected specimens and EOC cell culture, we established that EOC cells have elevated levels of HIF-1α and miR-92 expression, but the expression of VHL is reduced. We further demonstrated that miR-92 can target the VHL transcript to repress its expression. We also found that stabilized HIF-1α can form an active complex with transcriptional coactivator p300 and phosphorylated-STAT3 at the VEGF promoter to stimulate its expression. In addition, matrix metalloproteinases MMP-2 and MMP-9 are positively regulated by HIF-1α. These results suggest that miR-92 can potentially be considered as a novel therapeutical target in treatment of EOS.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , MicroARNs/biosíntesis , Neoplasias Ováricas/metabolismo , ARN Neoplásico/biosíntesis , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/biosíntesis , Línea Celular Tumoral , Femenino , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , MicroARNs/genética , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , ARN Neoplásico/genética , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Factores de Transcripción p300-CBP/genética , Factores de Transcripción p300-CBP/metabolismo
6.
Zhonghua Yan Ke Za Zhi ; 53(9): 689-693, 2017 Sep 11.
Artículo en Chino | MEDLINE | ID: mdl-28926887

RESUMEN

Objective: To observe the clinical characteristics of allergic conjunctivitis, and the correlations with skin prick test results. Methods: A retrospective study. Forty patients with positive skin prick test result were included. Patients underwent an ophthalmologic examination to identify their primary presenting signs and symptoms. The allergy types were divided into 5 groups. All dates were analyzed for the dependence, normality and homogeneity of variance. Chi-square test, Mann-Whitney U test, Kruskal-Wallis H test and Spearman correlation analysis were performed accordingly. Results: Among 40 patients, 18(45.0%) had a clinical diagnosis of seasonal allergic conjunctivitis, 14(35.0%) had perennial allergic conjunctivitis, 5(12.5%) had vernal keratoconjunctivitis, and 2(5.0%) had atopic keratoconjunctivits, and 1(2.5%) had giant papillary conjunctivitis. There was no significant difference in the number of symptoms and signs score among different types of allergic conjunctivitis, the score of itching and hyperemia had a positive relationship with the number of positive allergens (r=0.74, P<0.05. r=0.96, P<0.05). The primary symptoms and signs are itching and hyperemia; dust and pollens are the most common allergens. The more positive result of the test of the allergen, the more symptoms and signs encountered in terms of severity. Conclusion: Seasonal allergic conjunctivitis was the most prevalent disorder, the most important clinical characteristics of allergic conjunctivitis are itching and conjunctival congestion, the main allergens are dust and pollens, patients may be sensitive to multiple allergens. (Chin J Ophthalmol, 2017, 53: 689-693).


Asunto(s)
Conjuntivitis Alérgica , Alérgenos , Conjuntivitis Alérgica/diagnóstico , Humanos , Prevalencia , Estudios Retrospectivos , Pruebas Cutáneas
7.
Zhonghua Yan Ke Za Zhi ; 53(1): 18-22, 2017 Jan 11.
Artículo en Chino | MEDLINE | ID: mdl-28162195

RESUMEN

Objective: To study the safety, efficacy and tolerability of the usage of 0.1% bromfenac sodium eye drops in small incision lenticule extraction (SMILE). Methods: Prospective case control study. Three groups were observed, including 60 patients (60 eyes) undergoing SMILE for myopia. After surgery, 20 patients (20 eyes) were treated with 0.1% bromfenac sodium eye drops twice daily for 10 days, 20 patients (20 eyes) were treated with topical compound tobramycin eye drops 4 times daily for 10 days, and 20 patients (20 eyes) were treated with topical compound tobramycin eye drops 4 times daily for 3 days and 0.1% bromfenac sodium eye drops twice daily thereafter for 7 days. All of the patients were examined preoperatively and at 1 day, 10 days, 1 month and 3 months postoperatively, including visual acuity, intraocular pressure, topography and adverse reactions. The differences among the 3 groups were analyzed by the single factor analysis of variance. Results: There was no significant difference among the 3 groups in the uncorrected visual acuity at 10 days, 1 month and 3 months postoperatively (F=0.77, 0.30, 0.36. P=0.47, 0.75, 0.69) . The intraocular pressure in the dexamethasone group at 10 days, 1 month and 3 months postoperatively was higher than the other two groups with no significant difference (F=0.56, 0.98, 0.63. P=0.57, 0.38, 0.54) . The surface asymmetry index of patients was 0.33±0.10, 0.50±0.17 and 0.55±0.21 in the bromfenac sodium group, 0.33±0.08, 0.49±0.16 and 0.60±0.37 in the dexamethasone-bromfenac sodium group, and 0.31±0.12, 0.52±0.23 and 0.55±0.19 in the dexamethasone group; preoperatively and at 1 and 3 months, respectively. There was no significant difference among the 3 groups in the surface asymmetry index at 1 and 3 months postoperatively (F=0.09, 0.21. P=0.91, 0.81) . The surface regularity index of patients was 0.15±0.12, 0.34±0.18 and 0.40±0.18 in the bromfenac sodium group, 0.18±0.17, 0.33±0.26 and 0.33±0.26 in the dexamethasone-bromfenac sodium group, and 0.30±0.25, 0.41±0.28 and 0.34±0.29 in the dexamethasone group preoperatively and at 1 and 3 months, respectively. There was no significant difference among the 3 groups in the surface regularity index at 1 and 3 months postoperatively (F=0.74, 0.39. P= 0.48, 0.68) . In the bromfenac sodium group, one patient complained of binocular visual fatigue at 10 days, and one patient complained of dryness in one eye at 1 and 3 months. Conclusion: Bromfenac sodium eye drops can be used to replace corticosteroids after SMILE procedure with high safety and good tolerance. Satisfactory recovery of visual acuity, intraocular pressure and ocular surface could be achieved. (Chin J Ophthalmol, 2017, 53: 18-22).


Asunto(s)
Corticoesteroides/farmacología , Benzofenonas/farmacología , Bromobencenos/farmacología , Dexametasona/farmacología , Miopía/cirugía , Soluciones Oftálmicas/farmacología , Antibacterianos/farmacología , Estudios de Casos y Controles , Topografía de la Córnea , Esquema de Medicación , Femenino , Humanos , Presión Intraocular/efectos de los fármacos , Masculino , Estudios Prospectivos , Tobramicina/farmacología , Tonometría Ocular , Agudeza Visual/efectos de los fármacos
8.
J Helminthol ; 90(3): 359-63, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26123576

RESUMEN

We determined the prevalence and seasonality of infections by Fasciola of goats and bovine species (cattle and water buffalo) in Hubei and Anhui provinces of China. Faecal samples were collected at 2- to 3-month intervals from 200 goats in Hubei province and from 152 bovine species in Anhui province. All faecal samples were examined for the presence of parasites. We determined the nucleotide sequences of the first and second internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA (rDNA) of 39 Fasciola worms from Anhui province. The prevalence of Fasciola infection in goats ranged between 3.5 and 37.0%, with mean eggs per gram (EPG) ranging between 29.0 and 166.0. Prevalence and EPG exhibited downward trends over time with significant differences. The prevalence of Fasciola infection in cattle ranged between 13.3 and 46.2% (mean EPG, 36.4-100.0), and that of water buffalo ranged between 10.3 and 35.4% (mean EPG, 25.0-89.6), with a higher prevalence of infection and EPG from June to October compared with December to March. Analysis of ITS-1 and ITS-2 sequences revealed that F. hepatica and F. gigantica were present in all bovine species of Anhui province and that F. gigantica mainly infected water buffalo. This is the first demonstration of Fasciola infection in Hubei province and detection of F. hepatica and F. gigantica in Anhui province. The present study of Hubei province shows that mass treatment of livestock with closantel sodium injections in April and August/September controlled Fasciola infection effectively.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Fasciola/aislamiento & purificación , Fascioliasis/veterinaria , Enfermedades de las Cabras/epidemiología , Animales , Búfalos , Bovinos , Enfermedades de los Bovinos/parasitología , China/epidemiología , Análisis por Conglomerados , ADN de Helmintos/química , ADN de Helmintos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Fasciola/clasificación , Fasciola/genética , Fascioliasis/diagnóstico , Fascioliasis/parasitología , Heces/parasitología , Femenino , Enfermedades de las Cabras/parasitología , Cabras , Estudios Longitudinales , Masculino , Recuento de Huevos de Parásitos , Filogenia , Prevalencia , Estaciones del Año , Análisis de Secuencia de ADN
9.
Exp Clin Endocrinol Diabetes ; 121(8): 448-54, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23864493

RESUMEN

The incidence of gestational diabetes mellitus (GDM) has increased dramatically amongst multiethnic population. However, how gestational diabetes mellitus damages the developing embryo is still unknown. In this study, we used yolk sac membrane (YSM) model to investigate angiogenesis in the developing chick embryo. We determined that in the presence of high glucose, it retarded the growth and extension of the embryonic vascular plexus and it also reduced the density of the vasculature in yolk sac membrane model. Using the same strategy, we used the chorioallantoic membrane (CAM) as a model to investigate the influence of high glucose on the vasculature. We established that high glucose inhibited development of the blood vessel plexus and the blood vessels formed had a narrower diameter than control vessels. Concurrent with the abnormal angiogenesis, we also examined how it impacted cardiogenesis. We determined the myocardium in the right ventricle and left atrium were significantly thicker than the control and also there was a reduction in glycogen content in cardiomyocytes. The high glucose also induced excess reactive oxygen species (ROS) production in the cardiomyocytes. We postulated that it was the excess reactive oxygen species that damaged the cardiomyocytes resulting in cardiac hyperplasia.


Asunto(s)
Anomalías Cardiovasculares/inducido químicamente , Desarrollo Embrionario/efectos de los fármacos , Glucosa/efectos adversos , Animales , Anomalías Cardiovasculares/embriología , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/efectos de los fármacos , Edad Gestacional , Corazón/efectos de los fármacos , Corazón/embriología , Modelos Biológicos , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Neovascularización Fisiológica/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Saco Vitelino/irrigación sanguínea , Saco Vitelino/efectos de los fármacos
10.
Neuroscience ; 154(1): 304-14, 2008 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-18262366

RESUMEN

Using a microchemical approach, we measured changes of amino acid concentrations in the chinchilla caudal posteroventral cochlear nucleus (PVCN) after cochlear ablation to determine to what extent slow decreases of glutamate and aspartate concentrations after carboplatin treatment resulted from slower effects of cochlear damage in chinchillas than in rats and guinea pigs, as opposed to effects of carboplatin treatment being slower than those of cochlear ablation. Our results indicate that both factors are involved: decreases of glutamate and aspartate concentrations after cochlear ablation are much slower in chinchillas than in rats and guinea pigs, but they are much faster than the decreases after carboplatin treatment. Further, aspartate and glutamate concentrations in the chinchilla caudal PVCN decreased by larger amounts after cochlear ablation than in rats or guinea pigs, and there was a transient increase of aspartate concentration at short survival times. Detailed mapping of amino acid concentrations in the PVCN of a chinchilla with 1 month survival after cochlear ablation and a rat with 7 days' survival indicated that the reductions of glutamate and aspartate occurred throughout the PVCN but were somewhat larger in ventral and caudal parts in chinchilla. Any decreases in the adjacent granular region were very small. There were also sustained bilateral decreases in concentrations of other amino acids, notably GABA and glycine, in the caudal PVCN of cochlea-ablated chinchillas but not rats. The effects of cochlear ablation on the concentrations of most of these other amino acids in chinchilla caudal PVCN differed from those of carboplatin treatment. Thus, although a major effect of auditory nerve damage on the cochlear nucleus-decreases of glutamate and aspartate concentrations-occurs across species and types of lesions, the details of timing and magnitude and the effects on other amino acids can vary greatly.


Asunto(s)
Aminoácidos/metabolismo , Química Encefálica , Chinchilla/metabolismo , Cóclea/lesiones , Núcleo Coclear/metabolismo , Animales , Antineoplásicos/farmacología , Química Encefálica/efectos de los fármacos , Carboplatino/farmacología , Cromatografía Líquida de Alta Presión , Núcleo Coclear/efectos de los fármacos , Núcleo Coclear/patología , Electroquímica , Lateralidad Funcional , Masculino , Neurotransmisores/metabolismo , Ratas , Factores de Tiempo
11.
Phys Rev Lett ; 91(19): 197601, 2003 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-14611617

RESUMEN

A theory is developed for intermediate monoclinic (FE(m)) phases near morphotropic phase boundaries in ferroelectrics of complex oxides. It is based on the conformal miniaturization of stress-accommodating tetragonal domains under the condition of low domain-wall energy density. The microdomain-averaged lattice parameters are determined and attributed to the parameters of an adaptive monoclinic phase. The theory is applied to the temperature, electric field, and compositional dependent FE(m) lattice parameters. The predictions of the theory are rigidly obeyed over the entire FE(m) stability range.

12.
Plant Cell Rep ; 22(4): 268-73, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12920565

RESUMEN

The anther (tapetum)-specific gene BcA9 was isolated from Chinese cabbage, Brassica campestris L. ssp. pekinensis cv. Jangwon, using the Arabidopsis tapetum-specific A9 gene as a probe. The DNA and amino acid sequences of the coding region of the BcA9 gene showed high homology with A9 genes from Arabidopsis and B. napus. However, the DNA sequences of the 5' noncoding (promoter) region were different, except for the sequence from -281 to -89. To test the specific activity of this promoter, a plant expression vector, pGR011, was constructed by fusing the BcA9 promoter and the cytotoxic diphtheria toxin A-chain (DTx-A) gene. Several transgenic plants from cabbage, B. oleracea ssp. capitata, were obtained by way of Agrobacterium-mediated transformation. Southern blot analysis indicated that the tapetum-specific BcA9 promoter and DTx-A gene were successfully integrated into the genome of the transgenic cabbage. Under the control of the BcA9 promoter, expression of the cytotoxic DTx-A gene in the tapetal cells of the transgenic plants resulted in male sterile cabbages. Microscopic examination revealed that pollen grains in anthers of the male sterile cabbages had not developed normally, but the vegetative growth and phenotype showed no difference compared to wild-type plants.


Asunto(s)
Brassica/genética , Regiones Promotoras Genéticas , Secuencia de Bases , Brassica/fisiología , Clonación Molecular , ADN de Plantas , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente , Homología de Secuencia de Ácido Nucleico
13.
Artículo en Chino | MEDLINE | ID: mdl-12019443

RESUMEN

A 1949 bp cDNA fragment was amplified by RT-PCR from adult Schistosoma japonicum (Chinese strain) mRNA with 3 pair of primers that were designed according to published SmGCP gene encoding gynecophoral canal protein of Schistosoma mansoni and SjGCP1 gene encoding the conservative region of gynecophoral canal protein of Schistosoma japonicum. Sequence analysis indicated that this fragment, named SjGCP, with 85% identity to SmGCP, contained a complete open reading frame (ORF) of gynecophoral canal protein gene of Schistosoma japonicum (Chinese strain). The amino acid sequence shared 83.7% identity with gynecophoral canal protein of Schistosoma mansoni. This fragment was cloned into the expression vector pET28c(+) and subsequently expressed in Escherichia coli. SDS-PAGE revealed that the molecular weight of this expressed product was 80 kD. Western blotting showed that the recombinant protein reacted well with the rabbit serum immunized with Sj worm antigen, indicating that this expressed product had good antigenicity.


Asunto(s)
Glicoproteínas/genética , Proteínas del Helminto/genética , Schistosoma japonicum/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario/análisis , ADN de Helmintos/análisis , Escherichia coli , Expresión Génica , Glicoproteínas/biosíntesis , Proteínas del Helminto/biosíntesis , Datos de Secuencia Molecular , Schistosoma japonicum/metabolismo , Homología de Secuencia de Aminoácido
14.
J Viral Hepat ; 8(5): 322-30, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11555189

RESUMEN

Hepatitis B virus X (HBx) protein is a multifunctional protein that exerts dual activity on cell proliferation and death. Although HBx is thought to be a major determinant that leads to hepatocellular carcinoma, its pathophysiological role in humans remains to be established. Attempts have been made to evaluate the role of HBx in liver specimens derived from patients with chronic B viral hepatitis and hepatocellular carcinoma. Among 25 paired liver specimens of hepatocellular carcinoma and corresponding nontumour liver tissues, HBx mRNA was hardly detected and was significantly lower than other HBV transcripts. An immunohistochemical study demonstrated that expression of HBx protein was also lower than other HBV gene products. Interestingly, however, expression of HBx protein changed with the progression of chronic hepatitis. HBx was expressed in 5.0% of patients with chronic hepatitis without cirrhosis but increased to 44.8% in chronic hepatitis with cirrhosis. In contrast, only one (3.7%) of 27 hepatocellular carcinomas showed HBx positivity whereas 29.6% of surrounding nontumour tissues was still HBx-positive. These results suggest that HBx may play a major role at the promotion stage of carcinogenesis. Noticeably, HBx-positive cells were preferentially localized in the periportal region of chronic hepatitis or periphery of cirrhotic nodules where high necroinflammatory activity was accompanied. We found a positive correlation between HBx expression and periportal inflammatory activity (P < 0.001). Thus, HBx may potentiate cell destruction and regeneration of liver that provide an opportunity for the accumulation of genetic mutations, which contribute to multistep hepatocarcinogenesis.


Asunto(s)
Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/virología , Hepatitis B Crónica/patología , Hepatitis B Crónica/virología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Transactivadores/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Regulación Viral de la Expresión Génica , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/metabolismo , Hepatitis B Crónica/metabolismo , Hepatocitos/metabolismo , Hepatocitos/patología , Hepatocitos/virología , Humanos , Inmunohistoquímica , Inflamación/metabolismo , Inflamación/patología , Inflamación/virología , Neoplasias Hepáticas/metabolismo , ARN Viral/análisis , ARN Viral/genética , Transactivadores/genética , Proteínas Reguladoras y Accesorias Virales , Receptor fas/metabolismo
15.
Oncogene ; 19(45): 5163-72, 2000 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-11064453

RESUMEN

Hepatitis B virus X (HBx) protein implicated in the development of liver cancer may inhibit the function of p53 tumor suppressor protein through cytoplasmic retention of p53 protein. Here, we attempt to investigate whether the functional inhibition of p53 protein by HBx protein is reversible. First, we provide the evidence for the association of endogenous p53 protein with HBx by co-immunoprecipitation in stable Chang cells that express HBx protein in an inducible manner (ChangX-34). By immunofluorescence microscopy, the major location of p53 protein of ChangX-34 cells was confirmed at the nuclear periphery as well as in the cytoplasm where HBx protein is mainly expressed. Surprisingly, anticancer drug, adriamycin induces the nuclear translocation of p53 protein sequestered in the cytoplasm. This change is accompanied by the restoration of p53 activity, which results in increased transcriptional activity at the p53-responsive DNA elements as well as increase of p21WAF1 mRNA expression. Further, we observed the induction of cell death and G1 arrest in these cells upon adriamycin treatment regardless of HBx expression. Together, we demonstrate that functional inhibition of p53 protein through its cytoplasmic retention by HBx protein is reversible. These results may be extended into other tumors of which p53 activity is modulated by viral oncoproteins.


Asunto(s)
Doxorrubicina/farmacología , Antígenos de la Hepatitis B/metabolismo , Hígado/efectos de los fármacos , Transactivadores/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Antineoplásicos/farmacología , Compartimento Celular , Muerte Celular/efectos de los fármacos , Línea Celular , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Antígenos de la Hepatitis B/genética , Humanos , Hígado/citología , Regiones Promotoras Genéticas , Unión Proteica , Transporte de Proteínas , Proteínas Recombinantes/metabolismo , Transactivadores/genética , Transcripción Genética/efectos de los fármacos , Proteína p53 Supresora de Tumor/genética , Proteínas Reguladoras y Accesorias Virales
16.
Hepatogastroenterology ; 47(32): 371-4, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10791192

RESUMEN

BACKGROUND/AIMS: Acute liver failure either after liver resection or as part of underlying liver disease is still associated with high mortality. Hepatocyte transplantation in various forms has attracted attention recently. However, none of those reports have investigated the thorough and systematic analysis of effect of hepatocyte transplantation on acute liver failure induced by 90% hepatectomy. Therefore, we investigated systematic analysis of effect of hepatocyte transplantation on rats with acute liver failure. METHODOLOGY: Male Sprague-Dawley rats were used. Group I rats (n = 26) received intrasplenic injection of 2 x 10(7) hepatocytes in 0.3 mL Dulbecco's modified Eagle's medium (DMEM) 24 hours prior to 90% hepatectomy. Group II rats (n = 24) received intrasplenic injection of DMEM only. Twenty-two rats from group I and 20 from group II were observed for the determination of survival time. The remaining 8 (4/each group) rats were used to assess the liver function and regeneration. RESULTS: The hepatocyte bearing spleen revealed active glucose-6-phosphatase activity. In group I rats, the survival was longer and that group had more long-term survivors than those of group II controls. In group I, there was significant increase in the ratio of weight of remnant liver lobes to body weight. At 24 hours after hepatectomy, group I rats had improved biochemical parameters compared to those of group II rats. CONCLUSIONS: In rats with acute liver failure, intrasplenic hepatocyte transplantation acts as a bridge to support experimental rats from acute liver failure to liver regeneration, prolong survival in rats with acute liver failure and improve biochemical parameters.


Asunto(s)
Fallo Hepático Agudo/cirugía , Pruebas de Función Hepática , Trasplante de Hígado/patología , Trasplante Heterotópico/patología , Animales , Células Cultivadas/trasplante , Hepatectomía , Fallo Hepático Agudo/patología , Regeneración Hepática/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Bazo , Trasplante Homólogo
17.
J Korean Med Sci ; 15(6): 682-9, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11194195

RESUMEN

Radiation proctitis is a frequent acute complication encountered with pelvic irradiation. This study was aimed at establishing the optimal radiation dose for radiation-induced proctitis in rats. Female Wistar rats were used. The rectal specimens were examined morphologically at 5th and 10th day following 10-30 Gy irradiation in single fraction. With increasing dose, mucosal damage became worse, and there was a prominent reaction after > or =15 Gy. We selected 17.5 Gy as an optimal dose for radiation proctitis and examined specimens at day 1-14 and at week 4, 6, 8, and 12 after 17.5 Gy. The rectal mucosa revealed characteristic histological changes with time. An edema in lamina propria started as early as 1-2 days after irradiation and progressed into acute inflammation. On day 7 and 8, regeneration was observed with or without ulcer. Four weeks later, all regeneration processes have been completed with end result of either fibrosis or normal appearing mucosa. This study showed that the radiation injury of the rectum in rat develops in dose-dependent manner as it has reported in previous studies and suggested that 17.5 Gy in single fraction is the optimum dose to evaluate the protective effect of various medications for radiation proctitis in face of the clinical situation.


Asunto(s)
Proctitis , Recto/efectos de la radiación , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta en la Radiación , Femenino , Proctitis/etiología , Proctitis/mortalidad , Proctitis/patología , Ratas , Ratas Wistar , Recto/patología , Factores de Tiempo
18.
Clin Nucl Med ; 24(11): 874-9, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10551471

RESUMEN

PURPOSE: Resistance to chemotherapeutic drugs continues to be one of the major unsolved problems in the treatment of cancer. Multidrug resistance is defined as the ability of cells exposed to a single drug to develop resistance to a broad range of structurally and functionally unrelated drugs as a result of enhanced outward transport of drugs mediated by P-glycoprotein that is encoded by multidrug resistance genes. Recent evidence has shown that Tc-99m MIBI is a suitable transport substrate for P-glycoprotein. A potential advantage of Tc-99m MIBI SPECT is its superiority to diagnose noninvasively the presence of P-glycoprotein overexpression in vivo. In this study, the authors determined the association of enhanced MIBI efflux in Tc-99m MIBI SPECT with overexpression of P-glycoprotein in hepatocellular carcinoma. MATERIALS AND METHODS: Thirty-five patients with hepatocellular carcinoma were enrolled in the study. Tc-99m MIBI SPECT was performed 10 minutes after intravenous injection of 20 mCi Tc-99m MIBI. All patients had liver biopsy or surgery within 1 week of MIBI imaging. Immunohistochemical study of the biopsy or resected hepatocellular carcinoma specimens was performed using the avidin-biotin-peroxidase technique with monoclonal antibody JSB-1 directed against P-glycoprotein. RESULTS: On Tc-99m MIBI SPECT, 30 of 35 (85.7%) patients with hepatocellular carcinoma had no Tc-99m MIBI uptake in tumor lesions, whereas five patients with hepatocellular carcinoma had Tc-99m MIBI uptake in tumor lesions. P-glycoprotein expression was observed in tumor tissues of all the patients without Tc-99m MIBI uptake, whereas among the five patients with Tc-99m MIBI uptake, no P-glycoprotein expression was seen in tumor lesions (P < 0.015). CONCLUSION: Tc-99m MIBI SPECT is useful for noninvasively predicting the presence of MDR1 gene-encoded P-glycoprotein in patients with hepatocellular carcinoma.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Carcinoma Hepatocelular/diagnóstico por imagen , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/diagnóstico por imagen , Tecnecio Tc 99m Sestamibi , Tomografía Computarizada de Emisión de Fotón Único , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Carcinoma Hepatocelular/genética , Femenino , Genes MDR , Humanos , Técnicas para Inmunoenzimas , Hígado/metabolismo , Neoplasias Hepáticas/genética , Masculino , Persona de Mediana Edad , Radiofármacos
19.
Mol Cells ; 8(3): 310-7, 1998 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-9666468

RESUMEN

We previously showed that a 383 bp (-274 to approximately +109) promoter of a pollen-specific gene, GBAN215-6, had a property of a late gene in pollen development in transgenic tobacco plants. It drove GUS gene expression from uninucleate microspores to pollen tube growth of trinucleated cells. To more precisely characterize the specificity of the promoter, we placed the diphtheria toxin A-chain (DTx-A) coding region under the control of the GBAN215-6 promoter. Transgenic tobacco plants containing the GBAN215-6/DTx-1 were phenotypically normal until an early stage of flowering. The dehisced anthers do not contain pollen grains and the filament length of stamen was shorter than that of normal plants. Microscopic examination showed that ablation of pollen by the expression of DTx-A was variable. The transgenic tobacco plants containing one copy of the DTx-A gene show 50% aborted and 50% normal pollen, which suggests that this gene acts gametophytically. However, most of the transgenic plants with high copy number were male-sterile. When these male-sterile tobacco plants were backcrossed as female with pollen from wild-type tobacco plants, the fruit capsule sizes and seed yields of the next generation (BC1 lines) were severely reduced and the segregation of male-sterile to fertile plants in BC1 seeds was not Mendelian.


Asunto(s)
Brassica/genética , Hidrolasas de Éster Carboxílico/genética , Toxina Diftérica/genética , Genes de Plantas/genética , Nicotiana/genética , Fragmentos de Péptidos/genética , Plantas Tóxicas , Polen/genética , Fusión Artificial Génica , Brassica/enzimología , Fertilidad/genética , Gametogénesis/genética , Dosificación de Gen , Regulación Bacteriana de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente , Polen/citología , Polen/crecimiento & desarrollo , Regiones Promotoras Genéticas/genética , Proteínas Recombinantes/genética , Nicotiana/crecimiento & desarrollo
20.
J Korean Med Sci ; 13(3): 295-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9681809

RESUMEN

We report four cases of tubular adenoma of the gallbladder with spindle cell metaplasia. Three patients had solitary polyps in the gallbladder and the fourth had multiple (three) polyps. Only one patient who had a polyp of larger size had abdominal pain. Histologically, these tubular adenomas had characteristic morular foci composed of short spindle cells. These spindle cell components lacked intercellular bridges or cytoplasmic keratinization. Immunohistochemically, the spindle cells stained positively for one or more cytokeratins and negatively for vimentin, muscle actin and S-100 protein. Spindle cells are considered to represent the metaplastic component of the adenoma cells.


Asunto(s)
Adenoma/patología , Neoplasias de la Vesícula Biliar/patología , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma/patología , Femenino , Humanos , Masculino , Metaplasia/patología , Persona de Mediana Edad
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