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1.
Neuropsychol Rehabil ; 29(1): 144-159, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28051902

RESUMEN

This study examined the use of the Hong Kong version of the Rivermead Behavioral Memory Test-Third Edition (RBMT-3) for older adults, and by presenting the optimal cut-off scores for patients with cognitive impairments, and for a group of peers who have functional everyday cognition. Hundred older adults residing in community dwellings were recruited from three non-government organisations and completed the RBMT-3: 29 patients with mild to moderate dementia, 34 persons at risk for MCI, and 37 matched older adults with everyday functional cognition for a healthy control group (NC). The test has excellent inter-rater (ICC [2, 1] = 0.997), intra-rater (ICC [3, 1] = 0), and parallel version (ICC [3, 1] = 0.990) reliabilities, as well as satisfactory internal consistency (Cronbach's alpha: 0.643-0.832). The scores of the MCI group were significantly lower than those of NC group in four subtests. The optimal cut-off scaled scores of ≤ 41.5, ≤ 102.5, and ≤ 131.5 are suggested for the RBMT-3 to discriminate between patients with mild and moderate dementia, mild dementia and MCI, and MCI and NC, with sensitivities 73%, 100% and 94.1%, respectively. This version is useful to differentiate those with or without risk of cognitive impairments.


Asunto(s)
Trastornos del Conocimiento/psicología , Trastornos del Conocimiento/rehabilitación , Pruebas de Memoria y Aprendizaje/normas , Terapia Ocupacional/métodos , Evaluación de Resultado en la Atención de Salud/métodos , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Hong Kong , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa/métodos , Psicometría , Reproducibilidad de los Resultados
2.
Crit Rev Microbiol ; 44(1): 40-78, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28423970

RESUMEN

Antimicrobial resistance of disease-related microorganisms is considered a worldwide prevalent and serious issue which increases the failure of treatment outcomes and leads to high mortality. Considering that the increased resistance to systemic antimicrobial therapy often needs of the use of more toxic agents, topical antimicrobial therapy emerges as an attractive route for the treatment of infectious diseases. The topical antimicrobial therapy is based on the absorption of high drug doses in a readily accessible skin surface, resulting in a reduction of microbial proliferation at infected skin sites. Topical antimicrobials retain the following features: (a) they are able to escape the enzymatic degradation and rapid clearance in the gastrointestinal tract or the first-pass metabolism during oral administration; (b) alleviate the physical discomfort related to intravenous injection; (c) reduce possible adverse effects and drug interactions of systemic administrations; (d) increase patient compliance and convenience; and (e) reduce the treatment costs. Novel antimicrobials for topical application have been widely exploited to control the emergence of drug-resistant microorganisms. This review provides a description of antimicrobial resistance, common microorganisms causing skin and soft tissue infections, topical delivery route of antimicrobials, safety concerns of topical antimicrobials, recent advances, challenges and future prospective in topical antimicrobial development.


Asunto(s)
Antibacterianos/administración & dosificación , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Administración Tópica , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/metabolismo , Farmacorresistencia Bacteriana , Humanos , Enfermedades Cutáneas Bacterianas/microbiología , Infecciones de los Tejidos Blandos/microbiología
3.
Epidemiol Infect ; 146(4): 496-507, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29446343

RESUMEN

Simulation models are used widely in pharmacology, epidemiology and health economics (HEs). However, there have been no attempts to incorporate models from these disciplines into a single integrated model. Accordingly, we explored this linkage to evaluate the epidemiological and economic impact of oseltamivir dose optimisation in supporting pandemic influenza planning in the USA. An HE decision analytic model was linked to a pharmacokinetic/pharmacodynamics (PK/PD) - dynamic transmission model simulating the impact of pandemic influenza with low virulence and low transmissibility and, high virulence and high transmissibility. The cost-utility analysis was from the payer and societal perspectives, comparing oseltamivir 75 and 150 mg twice daily (BID) to no treatment over a 1-year time horizon. Model parameters were derived from published studies. Outcomes were measured as cost per quality-adjusted life year (QALY) gained. Sensitivity analyses were performed to examine the integrated model's robustness. Under both pandemic scenarios, compared to no treatment, the use of oseltamivir 75 or 150 mg BID led to a significant reduction of influenza episodes and influenza-related deaths, translating to substantial savings of QALYs. Overall drug costs were offset by the reduction of both direct and indirect costs, making these two interventions cost-saving from both perspectives. The results were sensitive to the proportion of inpatient presentation at the emergency visit and patients' quality of life. Integrating PK/PD-EPI/HE models is achievable. Whilst further refinement of this novel linkage model to more closely mimic the reality is needed, the current study has generated useful insights to support influenza pandemic planning.


Asunto(s)
Antivirales/economía , Antivirales/uso terapéutico , Análisis Costo-Beneficio , Gripe Humana/tratamiento farmacológico , Modelos Económicos , Modelos Teóricos , Oseltamivir/economía , Oseltamivir/uso terapéutico , Adolescente , Adulto , Anciano , Niño , Preescolar , Costos de los Medicamentos , Femenino , Humanos , Lactante , Gripe Humana/epidemiología , Masculino , Persona de Mediana Edad , Pandemias , Años de Vida Ajustados por Calidad de Vida
5.
Anaesthesia ; 70(3): 282-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25347936

RESUMEN

When considering brachial plexus block as a practical alternative to general anaesthesia for upper limb surgery, the time to achieve complete sensory block is a clinically important variable. In this prospective randomised double-blind controlled trial, we investigated the hypothesis that addition of hyaluronidase to ropivacaine may reduce the time to achieve complete sensory block after axillary brachial plexus block. The patients were randomly assigned into a hyaluronidase group (n = 24) and a control group (n = 24). The hyaluronidase group received ropivacaine 0.5% with 100 IU.ml(-1) of hyaluronidase, and the control group received ropivacaine alone. The primary endpoint was the time to achieve complete sensory block. The hyaluronidase group demonstrated significantly shorter mean (SD) sensory block onset time (13.8 (6.0) min) compared with the control group (22.5 (6.3) min, p < 0.0001). Addition of hyaluronidase to ropivacaine resulted in a reduction in the time needed to achieve complete sensory block.


Asunto(s)
Amidas/administración & dosificación , Anestésicos Locales/administración & dosificación , Bloqueo del Plexo Braquial/métodos , Plexo Braquial/efectos de los fármacos , Hialuronoglucosaminidasa/administración & dosificación , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Ropivacaína , Factores de Tiempo
6.
J Bone Miner Metab ; 32(1): 48-55, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23636506

RESUMEN

Population-based studies have revealed a decline in the incidence of age-adjusted hip fractures in southern Chinese women during the past decade. To determine whether there was a secular change in population characteristics that accounted for this decline, we compared the bone mineral density (BMD) and lifestyle habits of two cohorts of women who were more than 50 years of age and who were recruited from 1995 to 2000 and 2005 to 2010. The BMD levels in the 2005-2010 cohort were significantly higher at the spine and hip and ranged from 3.6 to 17.8% among the different age groups. Additionally, a significantly lower prevalence of subjects with osteoporosis and osteopenia was observed. Longer reproductive years, higher levels of physical activity, higher estradiol and 25(OH) vitamin D levels, and lower alkaline phosphatase levels were found in the 2005-2010 cohort. After adjusting for bone-determining factors, significant differences were detected in the BMD levels at the lumbar spine, femoral neck, and total hip (4.17, 9.02, and 9.34%, respectively) in women >50 years of age but not in women ≤50 years of age. The secular increase in BMD and healthier lifestyles most likely led to the decline in the incidence of age-adjusted fractures.


Asunto(s)
Pueblo Asiatico , Densidad Ósea/fisiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , China/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis/epidemiología , Osteoporosis/fisiopatología , Prevalencia , Factores de Riesgo , Adulto Joven
8.
J Microencapsul ; 31(8): 754-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24963963

RESUMEN

l-ascorbic acid is an abundant water-soluble nutrient found in vegetables and fruits. It enhances the cell proliferation, which is helpful in wound healing process. However, it is relatively unstable and easily degraded under external environments including acidity, alkalinity, evaporation, heat, oxidization, light or moisture. Its storage remains challenged. This study reported the development of l-ascorbic acid microcapsules using the natural protein, gelatin, and the natural polysaccharide, agar, as the wall protection carrier. The physical properties including entrapment efficiency, particle size, surface morphology, chemical compositions and release profile were identified. The cell proliferation of l-ascorbic acid microcapsules was stronger than the free drug. Significant cell growth in microencapsulated l-ascorbic acid-treated human epithelial HaCaT cells was observed when compared with untreated control. Since cell proliferation and wound repair are closely related, it is believed that l-ascorbic acid microcapsules would effectively increase the potential effect of wound healing activity in human skin.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Proliferación Celular/efectos de los fármacos , Células Epiteliales/metabolismo , Cicatrización de Heridas/efectos de los fármacos , Ácido Ascórbico/química , Cápsulas , Línea Celular , Células Epiteliales/citología , Humanos
9.
Nat Genet ; 28(2): 173-7, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11381267

RESUMEN

Despite recent successes in cloning various animal species, the use of somatic cells as the source of donor nuclei has raised many practically relevant questions such as increased abortion rates, high birth weight and perinatal death. These anomalies may be caused by incomplete epigenetic reprogramming of donor DNA. Genome-wide demethylation occurs during early development, 'erasing' gamete-specific methylation patterns inherited from the parents. This process may be a prerequisite for the formation of pluripotent stem cells that are important for the later development. Here, we provide evidence that cloned bovine embryos may have impaired epigenetic reprogramming capabilities. We found highly aberrant methylation patterns in various genomic regions of cloned embryos. Cloned blastocysts closely resembled donor cells in their overall genomic methylation status, which was very different from that of normal blastocysts produced in vitro or in vivo. We found demethylation of the Bov-B long interspersed nuclear element sequence in normal embryos, but not in cloned embryos, in which the donor-type methylation was simply maintained during preimplantation development. There were also significant variations in the degree of methylation among individual cloned blastocysts. Our findings indicate that the developmental anomalies of cloned embryos could be due to incomplete epigenetic reprogramming of donor genomic DNA.


Asunto(s)
Metilación de ADN , Embrión de Mamíferos/fisiología , Fertilización In Vitro , Animales , Secuencia de Bases , Blastocisto , Bovinos , Clonación de Organismos , Islas de CpG , Fibroblastos , Masculino , Datos de Secuencia Molecular
10.
Anal Chem ; 83(19): 7492-9, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21863800

RESUMEN

Hydrogen/deuterium exchange coupled to mass spectrometry (HDX-MS) has emerged as a technique for studying glycoproteins, which are often refractory to classical methods. Glycan chains are generally assumed to exchange protons very rapidly, making them invisible to this technique. Here, we show that under conditions commonly used for HDX-MS, acetamido groups within glycan chains retain a significant amount of deuterium. Using mono- and polysaccharide standards along with glycopeptides from a panel of glycoproteins, we demonstrate that N-acetyl hexosamines, along with modified Asn side chains, are responsible for this effect. Model compounds for sialic acid also displayed similar exchange kinetics, but terminal sialic acids in the context of an entire glycan chain did not contribute to deuterium retention. Furthermore, the presence of sialic acid appears to enhance the exchange rate of the nearby N-acetyl glucosamines. The ability to detect deuterium exchange at the glycan level opens the possibility of applying HDX-MS to monitor glycan interactions and dynamics.


Asunto(s)
Medición de Intercambio de Deuterio , Glicoproteínas/química , Polisacáridos/química , Animales , Conformación de Carbohidratos , Bovinos , Humanos , Espectrometría de Masas
11.
Scand J Rheumatol ; 40(6): 411-21, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21867445

RESUMEN

OBJECTIVE: To ascertain the effect of rosuvastatin on carotid atherosclerosis and arterial stiffness in patients with rheumatoid arthritis (RA). METHODS: Fifty RA patients were randomized in a double-blind placebo-controlled trial to receive 10 mg rosuvastatin (n = 24) or placebo (n = 26). Patients were followed prospectively every 3 months for 12 months. Intima-media thickness (IMT), augmentation index (AIx), and subendocardial viability ratio (SEVR) were measured at baseline, 6 and 12 months. RESULTS: Rosuvastatin resulted in statistically significant reductions of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), apolipoprotein B (Apo B), and urate levels vs. placebo. However, rosuvastatin had no significant effect on changes in inflammatory markers, including C-reactive protein (CRP) levels [from 2.9 (1.4-11.0) to 3.1 (0.9-13.3) mg/L in the rosuvastatin group compared with from 5.8 (2.6-14.2) to 4.4 (1.2-12.3) mg/L in the placebo group]. Nonetheless, a significant improvement in the Disease Activity Score (DAS) and a reduction in fibrinogen level was observed at 6 and 12 months compared with baseline in the rosuvastatin group. The treatment group exhibited a significant increase in SEVR (from 157 ± 28% to 163 ± 33% in the rosuvastatin group compared with from 143 ± 18% to 143 ± 26% in the placebo group, p = 0.023), but no significant effect was observed in the changes in IMT and AIx. CONCLUSION: Our data suggest that rosuvastatin has a modest anti-inflammatory effect in RA patients with low disease activity in terms of reduction in DAS and fibrinogen level. Rosuvastastin may also improve subendocardial perfusion and lower the urate level.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Aterosclerosis/tratamiento farmacológico , Fluorobencenos/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Pirimidinas/uso terapéutico , Sulfonamidas/uso terapéutico , Rigidez Vascular/efectos de los fármacos , Apolipoproteínas B/sangre , Artritis Reumatoide/fisiopatología , Aterosclerosis/fisiopatología , Grosor Intima-Media Carotídeo , Estenosis Carotídea/diagnóstico por imagen , Colesterol/sangre , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Factores de Riesgo , Rosuvastatina Cálcica , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Rigidez Vascular/fisiología
12.
Water Sci Technol ; 63(10): 2309-15, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21977654

RESUMEN

Reverse osmosis (RO) desalination has been recognized as a promising method to solve the water shortage problem. Nevertheless, since it is energy intensive and has many problems associated with biofouling/fouling of RO membranes in RO plants, its commercial acceptance is still slow. Especially, as high levels of oxidizing agents negatively affect RO membrane efficiency and life span. So, there is a need to develop sensitive, selective, portable and rapid methods to determine oxidation-reduction potential (ORP) in feed solution. For developing a polymer ORP lab-on-a-chip (LOC), a microchannel patterned on a polymer substrate was successfully filled with 800 nm diameter silica beads using self-assembly bead packing technology. The measured ORPs using the three kinds of redox potential solutions were typically slightly lower than those of the nominal redox potential. But, all of the measurements should be deemed acceptable. The ORP LOC has also a much shorter response time than the conventional potentiometric sensor.


Asunto(s)
Dispositivos Laboratorio en un Chip , Oxidación-Reducción , Sistemas Microelectromecánicos , Nanopartículas , Potenciometría , Abastecimiento de Agua
13.
Parasitology ; 137(2): 241-9, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19930758

RESUMEN

To investigate the phylogeny of benign Theileria parasites, we determined the complete major piroplasm surface protein (MPSP) gene sequences for 6 benign theilerial organisms, including the first from tick. Sequences were analysed alongside published sequences for 39 benign Theileria parasites, using Bayesian inference and maximum parsimony. All MPSP sequences were 852 nucleotides, except for Gansu, Wuchangbuf, VB01, and VB01; Gansu contained 873 nucleotides, and the other 3 had 855. Deduced amino acid sequences contained 284 residues, except for Gansu (291) and Wuchangbuf, VB01, and VB01 (285 each). Pairwise comparisons showed identities among 45 theilerial MPSP sequences ranging from 70.9 to 99.8% for nucleotide and 71.0 to 100% for amino acid sequences. Our results clearly indicate that all global parasites, excluding Brisbane, were classified into 1 of 8 types; 6 types of Theileria exist in Korea. Each type, excluding Type 6, has several type-specific amino acid sequences. The phylogenetic tree derived from the nucleotide sequences showed 2 sister-group relationships, Type 2+Type 7 and Type 3+Brisbane, with a new branching pattern: (Type 6 (Type 8 ((Type 2, Type 7), (Type 1, (Type 4, (Type 5, (Type 3, Brisbane))))))). Our sequence data showed no geographical influence on worldwide Theileria parasite distribution.


Asunto(s)
Antígenos de Protozoos/genética , Enfermedades de los Bovinos/parasitología , Filogenia , Proteínas Protozoarias/genética , Theileria/clasificación , Theileria/genética , Theileriosis/parasitología , Garrapatas/parasitología , Secuencia de Aminoácidos , Animales , Antígenos de Protozoos/química , Bovinos , Datos de Secuencia Molecular , Proteínas Protozoarias/química , Análisis de Secuencia de ADN , Theileria/aislamiento & purificación
14.
Clin Exp Dermatol ; 35(1): 22-6, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19489850

RESUMEN

BACKGROUND: Atopic eczema (AE) is characterized by reduced skin hydration (SH) and impaired integrity of the skin. Proper emollient usage is an important facet of AE management and patients are encouraged to use emollients liberally. AIM: To evaluate whether the amount of emollient and skin cleanser used correlates with eczema severity, SH or transepidermal water loss (TEWL), and whether liberal usage alters disease severity, SH and TEWL. METHODS: We studied SH and TEWL at three common measurement sites on the forearm (antecubital flexure, 20 mm below the antecubital flexure, mid-forearm) and determined the SCORing Atopic Dermatitis (SCORAD) score, Nottingham Eczema Severity Score (NESS), Children's Dermatology Life Quality Index (CDLQI) and the amount of emollient and cleanser usage over a 2-week period in consecutive new patients seen at the paediatric skin clinic of a teaching hospital. RESULTS: In total, 48 subjects and 19 controls were recruited. Patients with AE had significantly higher TEWL and lower SH in the studied sites. Emollient and cleanser usage was significantly higher (P = 0.001 and P = 0.041, respectively) in patients with AE than in controls. The amount of emollient usage was correlated with NESS, SCORAD, CDLQI, TEWL and mid-forearm SH. No such correlation was found with cleanser usage. Regardless of SCORAD, prescribing 130 g/m(2)/week of emollient met the requirement of 95.8% of patients, and 73 g/m(2)/week met that of 85.4%; for the cleanser, prescribing 136 g/m(2)/week met the requirement of 91.7% of patients. Although skin dryness and SH were improved, there was no significant improvement in SCORAD or TEWL after 2 weeks. In terms of global acceptability of treatment, three-quarters of patients with AE and controls rated the combination of cream and cleanser as 'good' or 'very good'. CONCLUSIONS: Adequate amounts of emollient and bathing cleanser should be prescribed to patients with AE. These amounts can be conveniently estimated based on body surface area instead of the less readily available tools for disease severity, degree of SH or skin integrity. However, liberal usage of emollients and bathing cleanser alone does not seem to alter disease severity or TEWL within 2 weeks, implying that additional treatments are necessary to manage AE.


Asunto(s)
Eccema/tratamiento farmacológico , Emolientes/uso terapéutico , Cuidados de la Piel/normas , Administración Cutánea , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Cumplimiento de la Medicación , Calidad de Vida , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
15.
J Clin Pharm Ther ; 35(3): 343-50, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20831535

RESUMEN

OBJECTIVE: Our study aimed to assess the effectiveness of esomeprazole or rabeprazole in combination with amoxicillin and clarithromycin for the eradication of Helicobacter pylori in Hong Kong non-ulcer dyspepsia (NUD) patients. METHODS: A prospective clinical trial was conducted at the Alice Ho Miu ling Nethersole Hospital outpatient endoscopy center from June 2004 to December 2005. Participants received amoxicillin 1 g, clarithromycin 500 mg, and, esomeprazole 20 mg (EAC) or rabeprazole 20 mg (RAC), all given twice daily for 1 week. The H. pylori status was determined by the [13C] urea breath test at least 4 weeks after completion of the treatment. Mutation status of CYP2C19 in exon 4 and exon 5 associated with the poor metabolizer phenotype was determined. RESULTS: The intention-to-treat eradication rates in patients treated with RAC and EAC were 77% and 84.6% respectively, and per protocol-based eradication rates were 83.7% and 88.9% respectively. The eradication rates did not vary with CYP2C19 phenotype found. For clarithromycin-sensitive strains, the cure rates were statistically significant regardless of CYP2C19 polymorphism (P < 0.0001). CONCLUSION: Triple therapy with either EAC or RAC is effective for Hong Kong Chinese NUD patients with H. pylori infection. Success eradication was related to clarithromycin resistance and not CYP2C19 genotype.


Asunto(s)
2-Piridinilmetilsulfinilbencimidazoles/uso terapéutico , Antibacterianos/uso terapéutico , Esomeprazol/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , 2-Piridinilmetilsulfinilbencimidazoles/administración & dosificación , Adulto , Amoxicilina/administración & dosificación , Amoxicilina/uso terapéutico , Antibacterianos/administración & dosificación , Antiulcerosos/administración & dosificación , Antiulcerosos/uso terapéutico , Hidrocarburo de Aril Hidroxilasas/genética , Pueblo Asiatico/genética , Pruebas Respiratorias/métodos , Claritromicina/administración & dosificación , Claritromicina/uso terapéutico , Citocromo P-450 CYP2C19 , Farmacorresistencia Bacteriana , Dispepsia/tratamiento farmacológico , Dispepsia/microbiología , Esomeprazol/administración & dosificación , Femenino , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/aislamiento & purificación , Hong Kong , Humanos , Masculino , Persona de Mediana Edad , Mutación , Farmacogenética , Polimorfismo Genético , Estudios Prospectivos , Rabeprazol , Urea/metabolismo
16.
Sci Adv ; 6(18): eaaz8822, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32494683

RESUMEN

The influenza virus hemagglutinin (HA) fusion protein has long been viewed as a "spring-loaded" fusion machine whereby activation at low pH initiates a rapid and irreversible cascade of conformational changes that drives the membrane fusion reaction. This mechanism has shaped our understanding of how type 1 viral fusion proteins function as a whole. Experimental limitations have hindered efforts to expand our mechanistic and structural understanding of viral membrane fusion. Here, we used pulse-labeling hydrogen/deuterium exchange mass spectrometry and cryo-electron tomography to monitor and characterize the structural dynamics of HA during fusion activation on intact virions. Our data reveal how concurrent reorganizations at the HA1 receptor binding domain interface and HA2 fusion subunit produce a dynamic fusion intermediate ensemble in full-length HA. The soluble HA ectodomain transitions directly to the postfusion state with no observable intermediate.


Asunto(s)
Gripe Humana , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Hemaglutininas , Humanos , Concentración de Iones de Hidrógeno , Conformación Proteica , Virión/metabolismo
17.
Nat Commun ; 11(1): 2614, 2020 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-32457321

RESUMEN

Causal mechanisms for fluid injection-induced earthquakes remain a challenge to identify. Past studies largely established spatiotemporal correlations. Here, we propose a multi-process causal mechanism for injection-induced earthquakes through a case study of the 2017 Mw 5.5 induced earthquake near Pohang Enhanced Geothermal System, Korea, where detailed hydraulic stimulation and on-site seismicity monitoring data provide an unprecedented opportunity. Pore pressure modeling reveals that pore pressure changes initiate seismicity on critically stressed faults and Coulomb static stress transfer modeling reveals that earthquake interactions promote continued seismicity, leading to larger events. On the basis of these results, we propose the following causal mechanism for induced seismicity: pore pressure increase and earthquake interactions lead to fault weakening and ultimately triggering larger earthquakes later in the process. We suggest that it is prudent that pore pressure change, initial seismicity locations, and Coulomb static stress transfer from seismicity earlier in the sequence are assessed in real-time.

18.
Breast Cancer Res Treat ; 113(3): 529-35, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18327706

RESUMEN

OBJECTIVES: This is a single center, randomized, double-blind placebo-controlled study to evaluate the NK(1)-receptor antagonist, aprepitant, in Chinese breast cancer patients. The primary objective was to compare the efficacy of aprepitant-based antiemetic regimen and standard antiemetic regimen for the prevention of chemotherapy-induced nausea and vomiting (CINV) in patients who received moderately emetogenic chemotherapy. The secondary objective was to compare the patient-reported quality of life in these two groups of patients. PATIENTS AND METHODS: Eligible breast cancer patients were chemotherapy-naive and treated with adjuvant AC chemotherapy (i.e. doxorubicin 60 mg/m(2) and cyclophosphamide 600 mg/m(2)). Patients were randomly assigned to either an aprepitant-based regimen (day 1, aprepitant 125 mg, ondansetron 8 mg, and dexamethasone 12 mg before chemotherapy and ondansetron 8 mg 8 h later; days 2 through 3, aprepitant 80 qd) or a control arm which consisted of standard regimen (day 1, ondansetron 8 mg and dexamethasone 20 mg before chemotherapy and ondansetron 8 mg 8 h later; days 2 through 3, ondansetron 8 mg bid). Data on nausea, vomiting, and use of rescue medication were collected with a self-report diary, patients quality of life were assessed by self-administered Functional Living Index-Emesis (FLIE). RESULTS: Of 127 patients randomized, 124 were assessable. For CINV in Cycle 1 AC, there was no significant difference in the proportion of patients with reported complete response, complete protection, total control, 'no vomiting', 'no significant nausea' and 'no nausea'. The requirement of rescue medication appears to be lesser in patients treated with the aprepitant-based regimen compared to those with the standard regimen (11% vs. 20%; P = 0.06). Assessment of FLIE revealed that while there was no difference in the nausea domain and the total score between the two groups; however, patients receiving standard antiemetic regimen had significantly worse quality of life in the vomiting domain (mean score [SD] = 23.99 [30.79]) when compared with those who received the aprepitant-based regimen (mean score [SD] = 3.40 [13.18]) (P = 0.0002). Both treatments were generally well tolerated. Patients treated with the aprepitant-based regimen had a significantly lower incidence of neutropenia (53.2% vs. 35.5%, P = 0.0468), grade >or= 3 neutropenia (21.0% vs. 45.2, P = 0.0042) and delay in subsequent cycle of chemotherapy (8.1% vs. 27.4%, P = 0.0048). CONCLUSION: The aprepitant regimen appears to reduce the requirement of rescue medication when compared with the control regimen for prevention of CINV in patients receiving both an anthracycline and cyclophosphamide, and is associated with a better quality of life during adjuvant AC chemotherapy.


Asunto(s)
Antieméticos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Morfolinas/administración & dosificación , Náusea/tratamiento farmacológico , Ondansetrón/administración & dosificación , Vómitos/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos/efectos adversos , Aprepitant , Carcinoma Ductal de Mama/tratamiento farmacológico , China , Dexametasona/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Náusea/inducido químicamente , Calidad de Vida , Vómitos/inducido químicamente
19.
Science ; 262(5135): 902-5, 1993 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-8235613

RESUMEN

The shc oncogene product is tyrosine-phosphorylated by Src family kinases and after its phosphorylation interacts with the adapter protein Grb2 (growth factor receptor-bound protein 2). In turn, Grb2 interacts with the guanine nucleotide exchange factor for Ras, mSOS. Because several Src family kinases participate in T cell activation and Shc functions upstream of Ras, the role of Shc in T cell signaling was examined. Shc was phosphorylated on tyrosine after activation through the T cell receptor (TCR), and subsequently interacted with Grb2 and mSOS. The Src homology region 2 (SH2) domain of Shc directly interacted with the tyrosine-phosphorylated zeta chain of the TCR. Thus, Shc may couple TCR activation to the Ras signaling pathway.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Activación de Linfocitos , Proteínas de la Membrana/metabolismo , Proteínas Oncogénicas/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Línea Celular , Receptores ErbB/metabolismo , Proteína Adaptadora GRB2 , Proteínas de Unión al GTP/metabolismo , Humanos , Hibridomas , Datos de Secuencia Molecular , Fosforilación , Proteínas/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal , Proteínas Son Of Sevenless , Linfocitos T/metabolismo , Tirosina/metabolismo
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