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1.
Phys Rev Lett ; 131(4): 043603, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566828

RESUMEN

We report the levitation of a superconducting lead-tin sphere with 100 µm diameter (corresponding to a mass of 5.6 µg) in a static magnetic trap formed by two coils in an anti-Helmholtz configuration, with adjustable resonance frequencies up to 240 Hz. The center-of-mass motion of the sphere is monitored magnetically using a dc superconducting quantum interference device as well as optically and exhibits quality factors of up to 2.6×10^{7}. We also demonstrate 3D magnetic feedback control of the motion of the sphere. The setup is housed in a dilution refrigerator operating at 15 mK. By implementing a cryogenic vibration isolation system, we can attenuate environmental vibrations at 200 Hz by approximately 7 orders of magnitude. The combination of low temperature, large mass, and high quality factor provides a promising platform for testing quantum physics in previously unexplored regimes with high mass and long coherence times.

2.
Clin Pharmacol Ther ; 81(4): 600-2, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17314925

RESUMEN

Historically females of all ages have been underrepresented in clinical research. Reasons for this exclusion are multifactorial and may possibly have their origins in regulation that forbid the participation of females of childbearing potential in the earliest phase clinical studies that support drug approval. Decades of female underrepresentation in clinical studies has resulted in inequality in the understanding, diagnosis, and treatment of disease between the sexes. Adequate numbers of both sexes is one approach which is likely to present overwhelming financial constraints. Advances in study design, statistical methodologies, and the promise of evolving technologies will lead to new tools that can foster a better understanding of the biology that governs sex and gender differences.


Asunto(s)
Ensayos Clínicos como Asunto/ética , Sujetos de Investigación , Mujeres , Femenino , Humanos , Masculino , Política Pública , Caracteres Sexuales , Estados Unidos , United States Food and Drug Administration
3.
Drug Discov Today Technol ; 4(2): 69-73, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-24980844

RESUMEN

Studying sex and gender differences is critical to understanding diseases that affect women solely, disproportionately or differently from men. Although inclusion of both sexes is essential in clinical research, advanced technology and analysis methods offer tools to define complex biological and physicochemical differences and improve prevention, diagnosis and treatments for diseases in women and men. This paper identifies the potential for biomarker development, pharmacogenetics and bioinformatics in research under the FDA Critical Path Initiative.:

4.
Circulation ; 101(12): 1396-402, 2000 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-10736283

RESUMEN

BACKGROUND: Hypertrophic cardiomyopathy is a myocardial disorder resulting from inherited sarcomeric dysfunction. We report a mutation in the myosin-binding protein-C (MyBP-C) gene, its clinical consequences in a large family, and myocardial tissue findings that may provide insight into the mechanism of disease. METHODS AND RESULTS: History and clinical status (examination, ECG, and echocardiography) were assessed in 49 members of a multigeneration family. Linkage analysis implicated the MyBP-C gene on chromosome 11. Myocardial mRNA, genomic MyBP-C DNA, and the myocardial proteins of patients and healthy relatives were analyzed. A single guanine nucleotide insertion in exon 25 of the MyBP-C gene resulted in the loss of 40 bases in abnormally processed mRNA. A 30-kDa truncation at the C-terminus of the protein was predicted, but a polypeptide of the expected size ( approximately 95 kDa) was not detected by immunoblot testing. The disease phenotype in this family was characterized in detail: only 10 of 27 gene carriers fulfilled diagnostic criteria. Five carriers showed borderline hypertrophic cardiomyopathy, and 12 carriers were asymptomatic, with normal ECG and echocardiograms. The age of onset in symptomatic patients was late (29 to 68 years). In 2 patients, outflow obstruction required surgery. Two family members experienced premature sudden cardiac death, but survival at 50 years was 95%. CONCLUSIONS: Penetrance of this mutation was incomplete and age-dependent. The large number of asymptomatic carriers and the good prognosis support the interpretation of benign disease.


Asunto(s)
Cardiomiopatía Hipertrófica/genética , Proteínas Portadoras/genética , Penetrancia , Adulto , Edad de Inicio , Anciano , Cardiomiopatía Hipertrófica/diagnóstico , Cromosomas Humanos Par 11 , Ecocardiografía , Electrocardiografía , Exones , Femenino , Ligamiento Genético , Genotipo , Heterocigoto , Humanos , Immunoblotting , Masculino , Persona de Mediana Edad , Mutación , Fenotipo
5.
J Clin Oncol ; 17(6): 1891-6, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10561230

RESUMEN

PURPOSE: Monitoring advanced malignant melanoma, serum levels of S100-beta (S100beta) and melanoma-inhibiting activity (MIA) were assessed for the ability to discriminate progressive from nonprogressive disease. S100beta and MIA were supposed to be superior to conventional variables, such as lactate dehydrogenase (LDH) level. PATIENTS AND METHODS: Seventy-one patients with stage IV malignant melanoma according to the criteria of the American Joint Committee on Cancer (AJCC) were included in the study. Results of restaging examinations were used as an independent reference standard for diagnosing progressive disease, and S100beta, MIA, LDH level, and erythrocyte sedimentation rate (ESR) were determined in venous blood just before restaging. Sensitivities and specificities of the parameters were calculated by logistic regression analysis. Discrimination ability was assessed by Somers' D(xy) rank correlation and the area under the receiver-operating characteristic curve (ROC-AUC). RESULTS: All tested serum parameters were significantly elevated in patients with progressive disease. The highest sensitivities according to the established thresholds were found for S100beta and MIA (91% and 88%, respectively). LDH had the highest specificity (92%). ESR was dropped from the analysis because of low specificity. In calculating Somers' D(xy) and ROC-AUC values, S100beta, MIA, and LDH showed high discrimination ability. By multiple logistic regression, LDH was identified to be the only statistically significant marker for progressive disease. S100beta and MIA did not provide additional significant information because of their high correlation with LDH with respect to clinical outcome. CONCLUSION: Elevated serum levels of S100beta, MIA, and LDH indicate current disease progression in AJCC stage IV melanoma. LDH was the most relevant overall parameter.


Asunto(s)
L-Lactato Deshidrogenasa/sangre , Melanoma/diagnóstico , Proteínas de Neoplasias/sangre , Estadificación de Neoplasias/métodos , Proteínas S100/sangre , Neoplasias Cutáneas/diagnóstico , Adulto , Anciano , Área Bajo la Curva , Biomarcadores de Tumor/sangre , Sedimentación Sanguínea , Progresión de la Enfermedad , Proteínas de la Matriz Extracelular , Femenino , Humanos , Modelos Logísticos , Masculino , Melanoma/sangre , Melanoma/enzimología , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Valores de Referencia , Sensibilidad y Especificidad , Neoplasias Cutáneas/sangre , Neoplasias Cutáneas/enzimología
6.
J Biochem Biophys Methods ; 19(2-3): 223-40, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2584609

RESUMEN

Human monoclonal antibodies against the transmembrane protein gp41 of HIV-1 were isolated and purified on a pilot scale. A purification scheme was established for the production of human monoclonal antibodies on the gram scale. 50 1 of culture supernatant can be treated in one purification cycle. The hybridomas were mass cultured in an airlift fermenter. The culture broth was clarified by microfiltration and chromatographed on CM-Sepharose fast flow and protein A Superose. Scale up of the high performance affinity chromatography from 1 ml protein A Superose up to 40 ml is described. All desalting steps were performed by gel filtration on Sephadex G-25 coarse. The yield of the whole purification procedure is in the range of 50-60%. The purity is higher than 99.9%. DNA and reverse transcriptase could not be detected. The whole method is designed as a basis for scale up to industrial scale. Results from quality control assays have proven the validity of this approach.


Asunto(s)
Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Anti-VIH/aislamiento & purificación , VIH-1/inmunología , Inmunoglobulina G/aislamiento & purificación , Western Blotting , Cromatografía de Afinidad/métodos , Cromatografía en Gel/métodos , Cromatografía por Intercambio Iónico/métodos , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Humanos , Hibridomas/inmunología , Inmunoglobulina G/análisis
7.
Eur J Pharm Sci ; 14(1): 63-7, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11457651

RESUMEN

The overproduction of biochemical mediators, and activation of leukocytes and endothelial cells, generated in thermally injured tissue, gives rise to both local and distant effects. The formation of short-lived, highly reactive metabolites, such as oxygen free radicals, increases with increasing tissue ischemia, and causes further cell damage. Human recombinant Cu/Zn-superoxide dismutase (rh-Cu/Zn-SOD), an enzyme which captures these radicals, may have a beneficial effect on the postburn inflammation processes. In this study, the influence of rh-Cu/Zn-SOD application to thermally injured tissue of rabbit backskin was examined. Three different delivery strategies were compared, pure or liposomally encapsulated enzyme, or intralesionally injected rh-Cu/Zn-SOD. For control, one animal group was treated with plain gel and another group was kept untreated. At 24 h following trauma a statistically significant difference in lesion sizes between the enzyme treated and control groups was observed. After 72 h tissue swelling had diminished significantly more in the rh-Cu/Zn-SOD treated groups as compared to the control animals. The best results were achieved by spreading liposomes encapsulating the enzyme onto the wounds. Our results suggest that local treatment of burn wounds with enzymatic radical scavengers such as rh-Cu/Zn-SOD has a beneficial effect on the extent of the postburn damage.


Asunto(s)
Quemaduras/tratamiento farmacológico , Depuradores de Radicales Libres/administración & dosificación , Depuradores de Radicales Libres/uso terapéutico , Superóxido Dismutasa/administración & dosificación , Superóxido Dismutasa/uso terapéutico , Animales , Quemaduras/patología , Composición de Medicamentos , Edema/tratamiento farmacológico , Edema/patología , Escherichia coli/metabolismo , Semivida , Liposomas , Tamaño de la Partícula , Conejos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/uso terapéutico , Piel/patología , Superóxido Dismutasa/biosíntesis
8.
Eur J Drug Metab Pharmacokinet ; 24(2): 169-76, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10510746

RESUMEN

Metabolism and disposition of most drugs used to treat malaria are substantially altered in malaria infection. Few data are available that specify effects of malaria infection on drug metabolism pathways in humans or animal model systems. In this report, studies were undertaken to determine the effect of Plasmodium berghei infection on cytochrome P-450 (CYP450) 2E1 and 3A2-mediated metabolism and enzyme expression in rat liver microsomes. Malaria infection (MAL) resulted in significant decreases in total cytochrome P-450 content (56%, P < 0.05) and NADPH cytochrome P-450 reductase activity (32%, P < 0.05) as compared to control (CON) rats. Chlorzoxazone 4-hydroxylase activity (CYP2E1-mediated) showed no significant difference between CON and MAL microsomes while testosterone 6-beta-hydroxylase activity (CYP3A2-mediated) was reduced by 41% (P < 0.05) in MAL. Enzyme kinetic studies and immunoblot analysis indicate that the loss of activity for CYP3A2 in malaria infection is due to significantly decreased CYP3A2 protein expression. The altered expression of CYP450s in malaria infection should be taken into account when treating patients with malaria in order to minimize drug-drug interactions or toxicity.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Hígado/metabolismo , Malaria/metabolismo , Microsomas Hepáticos/metabolismo , NADPH-Ferrihemoproteína Reductasa/metabolismo , Plasmodium berghei , Animales , Clorzoxazona/análisis , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Densitometría , Immunoblotting , Técnicas In Vitro , Hígado/enzimología , Malaria/enzimología , Masculino , Microsomas Hepáticos/enzimología , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , NADPH-Ferrihemoproteína Reductasa/genética , Plasmodium berghei/fisiología , Ratas , Ratas Sprague-Dawley , Esteroide Hidroxilasas/genética , Esteroide Hidroxilasas/metabolismo , Testosterona/análisis
9.
Urologe A ; 19(4): 226-30, 1980 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-7414768

RESUMEN

In patients with recurrent idiopathic nephrolithiasis we studied whether treatment with sodium cellulose phosphate leading to decreased intestinal calcium absorption could induce secondary hyperparathyroidism and whether thiazides which diminish calciuria would impair glucose tolerance. After removal of a actual kidney stone, 74 patients were treated for one year as follows: 25 (group 1) received conventional therapy (Nieron), 22 (group 2) received sodium cellulose phosphate, and 27 (group 3) received sodium cellulose phosphate plus hydrochlorothiazide. The period of one year was too short to evaluate the effectiveness of treatment regarding stone recurrence, however, a significant decrease in calciuria only was seen in group 3. With respect to the possibility to develop secondary hyperparathyroidism, group 2 and group 3 did not reveal any hints. In group 3, the thiazide treatment did not worsen glucose tolerance. Therefore, longer lasting studies with these drugs could be performed without evident danger to develop the mentioned side effects.


Asunto(s)
Calcio/metabolismo , Diabetes Mellitus/inducido químicamente , Hidroclorotiazida/efectos adversos , Hiperparatiroidismo Secundario/inducido químicamente , Cálculos Renales/tratamiento farmacológico , Celulosa/efectos adversos , Celulosa/análogos & derivados , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Hidroclorotiazida/uso terapéutico , Masculino , Recurrencia
15.
Clin Pharmacol Ther ; 86(4): 362-5, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19763116

RESUMEN

Approximately 3% of pregnant women take antidepressant medications. Information on the impact of antidepressants on short- and long-term maternal and offspring outcomes is highly desirable but neglected. The position that the dearth of treatment information is of greater concern than the risks to pregnant subjects involved in medical research is gaining support. Mandating the collection of reproductive outcome data in exposed childbearing women is an overdue step toward societal responsibility to our most vulnerable members.


Asunto(s)
Antidepresivos de Segunda Generación/efectos adversos , Ensayos Clínicos como Asunto , Trastorno Depresivo Mayor/tratamiento farmacológico , Selección de Paciente , Complicaciones del Embarazo/tratamiento farmacológico , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Antidepresivos de Segunda Generación/uso terapéutico , Femenino , Humanos , Embarazo , Resultado del Embarazo , Prevalencia , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico
16.
Clin Pharmacol Ther ; 83(1): 192-5, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17987048

RESUMEN

Our nationwide bioinformatics infrastructure used to detect important sex differences associated with medical product use is antiquated. The Food and Drug Administration (FDA) has embarked on an ambitious bioinformatics modernization effort that will improve our ability to assess the safety and effectiveness of new medical products. This, in turn, will improve our ability to detect important sex differences.


Asunto(s)
Biología Computacional/organización & administración , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , United States Food and Drug Administration/organización & administración , Salud de la Mujer , Ensayos Clínicos como Asunto , Seguridad de Productos para el Consumidor , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Difusión de la Información , Masculino , Selección de Paciente , Desarrollo de Programa , Medición de Riesgo , Factores Sexuales , Estados Unidos
19.
J Liposome Res ; 16(2): 113-25, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16753966

RESUMEN

Liposomes are potential drug carriers for pulmonary drug delivery: They can be prepared from phospholipids, which are endogenous to the respiratory tract as a component of pulmonary surfactant, and at an appropriate dose liposomes do not pose a toxicological risk to this organ. Among the various categories of drug that benefit from liposomal entrapment is the anti-inflammatory enzyme superoxide dismutase, thus prolonging its biological half-life. The delivery of liposomes by nebulization is hampered by stability problems, like physical and chemical changes that may lead to chemical degradation and leakage of the encapsulated drug. Here we present data of liposomes aerosolized with a novel electronic nebulizer based on a vibrating membrane technology (PARI eFlow), which amends drawbacks like liposomes degradation and product release. The data acquisition included aerosol properties such as aerodynamic particle size, nebulization efficiency, and liposome leakage upon nebulization. In conclusion, this study shows the ability of the PARI eFlow to nebulize high amounts of liposomal recombinant human superoxide dismutase with reduced vesicle disruption tested in an enclosing experimental protocol.


Asunto(s)
Liposomas/química , Nebulizadores y Vaporizadores , Superóxido Dismutasa/química , Vibración , Aerosoles , Sistemas de Liberación de Medicamentos , Estabilidad de Medicamentos , Estabilidad de Enzimas , Humanos , Tamaño de la Partícula , Estrés Mecánico
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