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1.
PLoS One ; 15(4): e0223304, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32302310

RESUMEN

INTRODUCTION: Sea-level rise is a consequence of climate change that can impact the ecological and physiological changes of coastal, ground-dwelling species. Sea-level rise has a potential to inundate birds, rodents, spiders, and insects that live on the ground in coastal areas. Yet, there is still much to be learned concerning the specifics of these impacts. The red imported fire ant Solenopsis invicta (Buren) excavates soil for its home and is capable of surviving flooding. Because of their ground-dwelling life history and rapid reproduction, fire ants make an ideal model for discovery and prediction of changes that may be due to sea-level rise. There are up to 500,000 individuals in a colony, and these invasive ants naturally have a painful sting. However, observations suggest that colonies of fire ants that dwell in tidally-influenced areas are more aggressive with more frequent stings and more venom injected per sting (behavioral and physiological changes) than those located inland. This may be an adaption to sea-level rise. Therefore, the objective of this study is to elucidate differences in inland and coastal defensiveness via micro-dissection and comparison of head width, head length, stinger length, and venom sac volume. But first because fire ants' ability to raft on brackish tidal water is unknown, it had to be determined if fire ants could indeed raft in brackish water and examine the behavior differences between those flooded with freshwater vs. saltwater. METHODS: To test the coastal-aggression hypothesis, inland colonies and coastal colonies, which experience relatively greater amounts of flooding, specifically regular tidal and windblown water and oscillations (i.e. El Nino Southern Oscillation) from the Gulf of Mexico, were collected. To mimic sea-level rise, the colonies were flooded in salinities that correspond to both their collection site and conditions found in a variety of locales and situations (such as storm surge from a tropical storm). Individual ants were immediately taken from each colony for dissection before flooding, 1-hour into flooding, and 24-hours into flooding. RESULTS AND DISCUSSION: Fire ants use their venom to defend themselves and to communicate alarm or aggression. Dissections and measurement of heads, venom sacs, and stingers revealed both coastal and inland colonies experience an increase in venom sac volume after 24 hours; in fact coastal colonies increased their venom volume by 75% after 24 h of flooding Whether this venom sac enlargement is due to diffusion of water or venom sac production is unknown. These ground-dwelling ants exhibit physiological and behavioral adaptations to ongoing sea-level rise possibly indicating that they are responding to increased flooding. Fire ants will raft on high-salinity water; and sea-level rise may cause stings by flooded ants to be more severe because of increased venom volume.


Asunto(s)
Adaptación Fisiológica , Hormigas/fisiología , Elevación del Nivel del Mar , Animales , Venenos de Artrópodos/metabolismo , Conducta Animal , Ecosistema
2.
Cancer Res ; 61(21): 8022-31, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11691828

RESUMEN

The cytokine hepatocyte growth factor/scatter factor (HGF/SF) protects epithelial and cancer cells against DNA-damaging agents via a pathway involving signaling from c-Met --> phosphatidylinositol-3- kinase --> c-Akt. However, the downstream alterations in gene expression resulting from this pathway have not been established. On the basis of cDNA microarray and semiquantitative RT-PCR assays, we found that MDA-MB-453 human breast cancer cells preincubated with HGF/SF and then exposed to Adriamycin (ADR), a DNA topoisomerase II inhibitor, exhibit an altered pattern of gene expression, as compared with cells treated with ADR only. [HGF/SF+ADR]-treated cells showed altered expression of genes involved in the DNA damage response, cell cycle regulation, signal transduction, metabolism, and development. Some of these alterations suggest mechanisms by which HGF/SF may exert its protective activity, e.g., up-regulation of polycystic kidney disease-1 (a survival-promoting component of cadherin-catenin complexes), down-regulation of 51C (an inositol polyphosphate-5-phosphatase), and down-regulation of TOPBP1 (a topoisomerase IIB binding protein). We showed that enforced expression of the cdc42-interacting protein CIP4, a cytoskeleton-associated protein for which expression was decreased in [HGF/SF+ADR]-treated cells, inhibited HGF/SF-mediated protection against ADR. The cDNA microarray approach may open up new avenues for investigation of the DNA damage response and its regulation by HGF/SF.


Asunto(s)
Neoplasias de la Mama/genética , Daño del ADN/fisiología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Factor de Crecimiento de Hepatocito/farmacología , Antibióticos Antineoplásicos/farmacología , Neoplasias de la Mama/metabolismo , Doxorrubicina/farmacología , Perfilación de la Expresión Génica , Humanos , Proteínas Asociadas a Microtúbulos/fisiología , Antígenos de Histocompatibilidad Menor , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas/efectos de los fármacos
4.
J Am Acad Dermatol ; 45(2): 187-95, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11464179

RESUMEN

BACKGROUND: Isotretinoin is very frequently the drug of choice for the management of severe recalcitrant nodular acne. Recently, a new micronized and more bioavailable formulation of isotretinoin has been developed that permits once-daily administration in lower doses than usually used with standard isotretinoin (Accutane), regardless of whether it is taken with or without food. OBJECTIVE: Our purpose was to determine whether micronized isotretinoin and standard isotretinoin are clinically equivalent. METHODS: In this multicenter, double-blind, double-dummy study, 600 patients with severe recalcitrant nodular acne were treated with either 0.4 mg/kg of micronized isotretinoin once daily without food (n = 300) or 1.0 mg/kg per day of standard isotretinoin in two divided doses with food (n = 300). Lesion counts were monitored over 20 weeks. RESULTS: Both treatment groups in this well-controlled clinical trial experienced an equivalent reduction in the number of total nodules (facial plus truncal). In addition, an equivalent proportion of patients achieved 90% clearance of the total number of nodules. Both formulations had similar results for other efficacy variables. CONCLUSION: Once-daily use of the micronized and more bioavailable formulation of isotretinoin under fasted conditions is clinically equivalent to the standard twice-daily formulation under fed conditions in the treatment of severe recalcitrant nodular acne.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Isotretinoína/administración & dosificación , Acné Vulgar/patología , Adolescente , Adulto , Disponibilidad Biológica , Niño , Formas de Dosificación , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Isotretinoína/farmacocinética , Masculino , Persona de Mediana Edad , Comprimidos
5.
J Am Acad Dermatol ; 45(2): 196-207, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11464180

RESUMEN

BACKGROUND: Isotretinoin is a very effective drug for treating severe recalcitrant nodular acne. A new micronized formulation of isotretinoin has been shown to be clinically equivalent to standard isotretinoin with improved bioavailability and minimal food effect. The safety profile of the micronized formulation has not been described previously. OBJECTIVE: The objective of this article is to report the incidence and intensity of adverse events found in a comparative, double-blind efficacy study that showed clinical equivalence of the new micronized formulation of isotretinoin and the standard isotretinoin formulation (Accutane). METHODS: Six hundred patients with severe recalcitrant nodular acne were treated with micronized isotretinoin (n = 300) under fasted conditions or standard isotretinoin (n = 300) under fed conditions. One cohort received single daily doses of 0.4 mg/kg of micronized isotretinoin without food and the other cohort received 1.0 mg/kg per day of standard isotretinoin in two divided doses with food. Adverse events were monitored during 20 weeks of drug therapy. RESULTS: The proportion of adverse events in most body systems was generally lower in patients receiving micronized isotretinoin than in those receiving standard isotretinoin. CONCLUSION: Micronized isotretinoin appears to have a safety profile similar to that of standard isotretinoin and to carry a lower risk of mucocutaneous events and hypertriglyceridemia.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Isotretinoína/efectos adversos , Acné Vulgar/patología , Afecto/efectos de los fármacos , Disponibilidad Biológica , Depresión/inducido químicamente , Formas de Dosificación , Método Doble Ciego , Esquema de Medicación , Cefalea/inducido químicamente , Humanos , Isotretinoína/administración & dosificación , Isotretinoína/farmacocinética , Lípidos/sangre , Pruebas de Función Hepática , Membrana Mucosa/efectos de los fármacos , Piel/efectos de los fármacos , Comprimidos , Xeroftalmia/inducido químicamente
6.
Leuk Lymphoma ; 40(3-4): 287-94, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11426550

RESUMEN

Adult T-cell leukemia/lymphoma (ATL) is frequently a very aggressive malignancy with a poor survival despite aggressive multiagent chemotherapy. The combination of the antiretroviral drug zidovudine (AZT) and interferon alpha (IFNalpha) has been reported to induce remissions in patients with ATL. The purpose of this study was to evaluate the clinical response and toxicity following administration of a combination of IFNalpha-2b and AZT in patients with human T-cell lymphotropic virus type I (HTLV-I)-associated ATL. Eighteen patients with ATL (chronic. crisis, acute or lymphoma type) were treated with the combination of AZT (50 - 200 mg orally 5 times a day) and IFNalpha-2b (2.5 - 10 million units subcutaneously daily). Three patients had objective responses lasting more than one month. One patient had a clinical complete remission, lasting 21.6 months and two patients had partial remissions lasting 3.7 and 26.5 months. Six patients were not considered evaluable for response due to short and/or interrupted periods of treatment. Seventeen patients have died with a median survival time after initiation of therapy of 6 months. Neutropenia and thrombocytopenia were the dose limiting toxicities. In conclusion, the response rate in this study was lower than noted in the two previous published series. This may be due to the amount and type of prior treatment our patients had received.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Interferón-alfa/administración & dosificación , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , Zidovudina/administración & dosificación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Supervivencia sin Enfermedad , Femenino , Humanos , Interferón alfa-2 , Interferón-alfa/toxicidad , Leucemia-Linfoma de Células T del Adulto/complicaciones , Leucemia-Linfoma de Células T del Adulto/mortalidad , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neutropenia/inducido químicamente , Proteínas Recombinantes , Inducción de Remisión , Pruebas Cutáneas , Trombocitopenia/inducido químicamente , Resultado del Tratamiento , Zidovudina/toxicidad
7.
Clin Immunol ; 99(1): 94-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11286545

RESUMEN

X-linked agammaglobulinemia (XLA), caused by mutations in Bruton's tyrosine kinase (BTK), typically presents in early childhood. We report here the case of a male diagnosed at age 23 years with hypogammaglobulinemia, originally classified as common variable immunodeficiency (CVID). On further analysis at age 40, flow cytometric analysis of lymphocytes showed only 0.1% B cells and Western blot analysis showed a deficiency of BTK protein in peripheral blood mononuclear cells, indicating the patient has XLA. BTK cDNA and genomic DNA analysis revealed a splice site mutation at the 3' end of intron 13. Multiple abnormally spliced mRNA species were identified, one of which was predicted to produce a protein with a 24-amino-acid insertion between the SH2 and kinase domains. In vitro kinase assay of this product showed weak kinase activity, perhaps resulting in milder than usual disease. XLA can present in adult males, and sporadic cases may be misdiagnosed as CVID.


Asunto(s)
Agammaglobulinemia/genética , Ligamiento Genético , Proteínas Tirosina Quinasas/genética , Cromosoma X , Adulto , Agammaglobulinemia Tirosina Quinasa , Humanos , Masculino , Empalme del ARN , ARN Mensajero/análisis
8.
J Cutan Med Surg ; 5(1): 37-42, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11281433

RESUMEN

BACKGROUND: Topical clindamycin and benzoyl peroxide have each demonstrated clinical efficacy in the treatment of acne vulgaris. When used in tandem, they promise greater efficacy than either individual agent through their antibacterial and anti-inflammatory effects. OBJECTIVE: To determine the efficacy and safety of combination benzoyl peroxide/ clindamycin compared with benzoyl peroxide or benzoyl peroxide/erythromycin in the treatment of acne. METHODS: In this randomized, 10-week, multicenter, single-blind trial, 492 patients with moderate to moderately severe acne were treated twice daily with 5% benzoyl peroxide/1% clindamycin, 5% benzoyl peroxide, or 5% benzoyl peroxide/3% erythromycin and assessed every 2 weeks. RESULTS: Compared with benzoyl peroxide, benzoyl peroxide/clindamycin demonstrated significantly greater reductions in inflammatory lesions (p = 0.04) and significantly greater overall improvement as assessed by physicians (p < or = 0.04) and patients (p < 0.001). Benzoyl peroxide/clindamycin demonstrated a nonsignificant trend for greater efficacy compared to benzoyl peroxide/erythromycin. Dry skin was the most frequent (< or = 7.3%) adverse event with all three therapies. CONCLUSION: Benzoyl peroxide/clindamycin demonstrated improved efficacy and similar tolerability; to benzoyl peroxide used alone and was similar to benzoyl peroxide/ erythromycin, making this combination product an effective alternative antimicrobial therapy for acne.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Antibacterianos/administración & dosificación , Peróxido de Benzoílo/administración & dosificación , Clindamicina/administración & dosificación , Eritromicina/administración & dosificación , Administración Tópica , Adolescente , Combinación de Medicamentos , Femenino , Geles , Humanos , Masculino , Método Simple Ciego
9.
Endocrinology ; 142(1): 98-107, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11145571

RESUMEN

Interferon-tau (IFNtau), a type I IFN produced by sheep conceptus trophectoderm, is the signal for maternal recognition of pregnancy. Although it is clear that IFNtau suppresses transcription of the estrogen receptor alpha and oxytocin receptor genes and induces expression of various IFN-stimulated genes within the endometrial epithelium, little is known of the signal transduction pathway activated by the hormone. This study determined the effects of IFNtau on signal transducer and activator of transcription (STAT) activation, expression, DNA binding, and transcriptional activation using an ovine endometrial epithelial cell line. IFNtau induced persistent tyrosine phosphorylation and nuclear translocation of STAT1 and -2 (10 min to 48 h), but transient phosphorylation and nuclear translocation of STAT3, -5a/b, and -6 (10 to <60 min). IFNtau increased expression of STAT1 and -2, but not STAT3, -5a/b, and -6. IFN-stimulated gene factor-3 and STAT1 homodimers formed and bound an IFN-stimulated response element (ISRE) and gamma-activated sequence (GAS) element, respectively. IFNtau increased transcription of GAS-driven promoters at 3 h, but suppressed their activity at 24 h. In contrast, the activity of an ISRE-driven promoter was increased at 3 and 24 h. These results indicate that IFNtau activates multiple STATs and has differential effects on ISRE- and GAS-driven gene transcription.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Endometrio/fisiología , Células Epiteliales/fisiología , Interferón Tipo I/farmacología , Proteínas Gestacionales/farmacología , Transactivadores/genética , Transactivadores/metabolismo , Transcripción Genética/fisiología , Animales , Núcleo Celular/metabolismo , Células Cultivadas , Endometrio/citología , Células Epiteliales/citología , Femenino , Interferón Tipo I/fisiología , Factor 3 de Genes Estimulados por el Interferón , Luciferasas , Fosforilación , Proteínas Gestacionales/fisiología , Regiones Promotoras Genéticas , Transporte de Proteínas , Proteínas Recombinantes de Fusión/análisis , Factor de Transcripción STAT1 , Factor de Transcripción STAT2 , Ovinos , Transducción de Señal , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos , Transfección
10.
Curr Allergy Asthma Rep ; 1(6): 558-65, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11892085

RESUMEN

X-linked, or Bruton's, agammaglobulinemia (XLA) was described in 1952 as the congenital inability to form antibodies. Patients were typically infants or young children with recurrent, severe bacterial infections. Other, milder cases of hypogammaglobulinemia were considered "acquired," and often presented later in life. Since the discovery of the defective gene in XLA in 1993, it has been shown that a significant number of male patients with sporadic or acquired hypogammaglobulinemia actually have XLA. We present here a case of atypical XLA and discuss similar cases in the literature. We conclude that any male with hypogammaglobulinemia, regardless of age of presentation, might have XLA. Males with low B-cell numbers are particularly likely to have XLA and should have Bruton's tyrosine kinase levels assessed.


Asunto(s)
Agammaglobulinemia/diagnóstico , Adulto , Agammaglobulinemia/genética , Agammaglobulinemia/inmunología , Linfocitos B/inmunología , Análisis Mutacional de ADN , Progresión de la Enfermedad , Humanos , Recuento de Linfocitos , Masculino , Mutación , Proteínas Tirosina Quinasas/genética , Cromosoma X/genética
11.
Curr Opin Allergy Clin Immunol ; 1(6): 525-33, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11964736

RESUMEN

The Wiskott-Aldrich syndrome is an inherited X-linked disorder characterized by immune deficiency, eczema, and thrombocytopenia with small platelets. The mutated protein, Wiskott-Aldrich syndrome protein, is an activator of actin cytoskeletal reorganization in hematopoietic cells. Members of the Wiskott-Aldrich syndrome protein family are being shown to be key integrators of cell signalling and cytoskeletal organization in many eukaryotic cell types. This review focuses on recent discoveries that reveal in increasing detail how Wiskott-Aldrich syndrome protein and its related proteins operate.


Asunto(s)
Citoesqueleto/metabolismo , Activación de Linfocitos/inmunología , Proteínas/metabolismo , Síndrome de Wiskott-Aldrich/fisiopatología , Humanos , Proteínas/genética , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/inmunología , Proteína del Síndrome de Wiskott-Aldrich
12.
Cutis ; 68(4 Suppl): 34-40, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11845946

RESUMEN

Adapalene gel 0.1% is approved for use in the treatment of acne vulgaris. A new cream formulation, adapalene cream 0.1%, has been developed. Our objective was to evaluate the efficacy and tolerability of adapalene cream 0.1% in comparison with its cream vehicle, applied once daily for 12 weeks to patients with facial acne vulgaris. We used a 12-week, multicenter, randomized, double-blind, vehicle-controlled, comparative phase 3 study of adapalene cream 0.1% and cream vehicle. The study enrolled 237 patients (125 males and 112 females), aged 12 through 30 years, with mild-to-moderate acne vulgaris. Adapalene cream 0.1% demonstrated superior efficacy compared with its cream vehicle. Significantly lower numbers of total inflammatory and noninflammatory lesion counts were observed at the end of the study period in patients using adapalene cream 0.1% as opposed to those using cream vehicle (P<.05 compared with baseline, for all 3 parameters). Adapalene cream 0.1% caused more cutaneous side effects than the cream vehicle, but these were tolerated in most patients. In summary, the results of this study indicate that adapalene cream 0.1% demonstrates superior efficacy over cream vehicle for the treatment of acne vulgaris. Adapalene cream 0.1% also has excellent tolerability and is associated with a low incidence of cutaneous adverse events.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Antiinflamatorios no Esteroideos/uso terapéutico , Fármacos Dermatológicos/uso terapéutico , Naftalenos/uso terapéutico , Adapaleno , Administración Tópica , Adolescente , Adulto , Niño , Método Doble Ciego , Femenino , Humanos , Masculino , Vehículos Farmacéuticos/administración & dosificación , Sensibilidad y Especificidad , Resultado del Tratamiento
13.
J Biol Chem ; 275(11): 7854-61, 2000 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-10713100

RESUMEN

The Wiskott-Aldrich syndrome is an inherited X-linked immunodeficiency characterized by thrombocytopenia, eczema, and a tendency toward lymphoid malignancy. Lymphocytes from affected individuals have cytoskeletal abnormalities, and monocytes show impaired motility. The Wiskott-Aldrich syndrome protein (WASP) is a multi-domain protein involved in cytoskeletal organization. In a two-hybrid screen, we identified the protein Cdc42-interacting protein 4 (CIP4) as a WASP interactor. CIP4, like WASP, is a Cdc42 effector protein involved in cytoskeletal organization. We found that the WASP-CIP4 interaction is mediated by the binding of the Src homology 3 domain of CIP4 to the proline-rich segment of WASP. Cdc42 was not required for this interaction. Co-expression of CIP4 and green fluorescent protein-WASP in COS-7 cells led to the association of WASP with microtubules. In vitro experiments showed that CIP4 binds to microtubules via its NH(2) terminus. The region of CIP4 responsible for binding to active Cdc42 was localized to amino acids 383-417, and the mutation I398S abrogated binding. Deletion of the Cdc42-binding domain of CIP4 did not affect the colocalization of WASP with microtubules in vivo. We conclude that CIP4 can mediate the association of WASP with microtubules. This may facilitate transport of WASP to sites of substrate adhesion in hematopoietic cells.


Asunto(s)
Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas/metabolismo , Síndrome de Wiskott-Aldrich , Sitios de Unión , Técnica del Anticuerpo Fluorescente , Humanos , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/aislamiento & purificación , Antígenos de Histocompatibilidad Menor , Pruebas de Precipitina , Unión Proteica , Proteínas/aislamiento & purificación , Tubulina (Proteína)/aislamiento & purificación , Técnicas del Sistema de Dos Híbridos , Proteína del Síndrome de Wiskott-Aldrich , Proteína de Unión al GTP cdc42/metabolismo , Dominios Homologos src
14.
Gene Ther ; 6(6): 1170-4, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10455421

RESUMEN

Boys affected with Wiskott-Aldrich syndrome (WAS) present with variable association of thrombocytopenia, eczema and immune deficiency. If untreated, WAS patients may succumb to intracerebral hemorrhages, severe infections or malignancies. Allogeneic bone marrow transplantation (BMT) can cure all aspects of the disease, but HLA-identical donors are not available to all patients and mismatched BMTs are unfortunately associated with high mortality and morbidity. The good success of HLA-matched BMT, however, makes WAS a potential candidate for hematopoietic stem cell gene therapy. WAS patients carry mutations of the Wiskott-Aldrich syndrome protein gene encoding WASP, a 502-amino acid proline-rich protein with demonstrated involvement in the organization of the actin cytoskeleton. To verify the feasibility of genetic correction for this disease, the WASP cDNA was expressed in EBV-immortalized B cell lines obtained from WAS patients using a retroviral vector. Transduced WAS cells showed levels of WASP expression similar to those found in cells from normal donors, without detectable effects on viability or growth characteristics. In addition, retrovirus-mediated expression of WASP led to improvement of cytoplasmic F-actin expression and formation of F-actin-positive microvilli, a process shown to be defective in untransduced WAS cell lines. These preliminary results indicate a potential use for retrovirus-mediated gene transfer as therapy for WAS.


Asunto(s)
Actinas/metabolismo , Terapia Genética/métodos , Mutación/genética , Síndrome de Wiskott-Aldrich/genética , Linfocitos B/metabolismo , Western Blotting , Línea Celular , Vectores Genéticos , Humanos
15.
J Immunol ; 162(8): 5019-24, 1999 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10202051

RESUMEN

Wiskott-Aldrich syndrome (WAS) is an X-linked recessive disorder characterized by thrombocytopenia, eczema, immune deficiency, and a proclivity toward lymphoid malignancy. Lymphocytes of affected individuals show defects of activation, motility, and cytoskeletal structure. The disease gene encodes a 502-amino acid protein named the WAS protein (WASP). Studies have identified a number of important interactions that place WASP in a role of integrating signaling pathways with cytoskeletal function. We performed a two-hybrid screen to identify proteins interacting with WASP and cloned a proline-rich protein as a specific WASP interactor. Our clone of this protein, termed WASP interacting protein (WIP) by others, shows a difference in seven amino acid residues, compared with the previously published sequence revealing an additional profilin binding motif. Deletion mutant analysis reveals that WASP residues 101-151 are necessary for WASP-WIP interaction. Point mutant analyses in the two-hybrid system and in vitro show impairment of WASP-WIP interaction with three WASP missense mutants known to cause WAS. We conclude that impaired WASP-WIP interaction may contribute to WAS.


Asunto(s)
Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Mutación Missense , Proteínas/genética , Proteínas/metabolismo , Síndrome de Wiskott-Aldrich/genética , Animales , Clonación Molecular , Proteínas del Citoesqueleto , Análisis Mutacional de ADN , Humanos , Células Híbridas , Péptidos y Proteínas de Señalización Intracelular , Ensayo de Unión Radioligante , Saccharomyces cerevisiae/genética , Eliminación de Secuencia , Proteína del Síndrome de Wiskott-Aldrich
16.
J Pathol ; 185(1): 99-107, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9713366

RESUMEN

The Wiskott-Aldrich syndrome (WAS) is a rare X-linked recessive disorder characterized by eczema, thrombocytopenia, and immunodeficiency. An allelic variant of the disease is characterized by isolated thrombocytopenia (XLT). The gene responsible for WAS/XLT (WASP) encodes for a 502 amino acid protein (WASP) that is possibly involved in actin binding and cytoskeleton organization. The expression of WASP and the distribution of F-actin and alpha-actinin (which binds to and stabilizes actin filaments) have been analysed in lymphoblastoid cell lines from six patients with WAS and one with XLT. Western blot and immunocytochemistry did not reveal WASP expression in four WAS patients, whereas two WAS patients (with a moderate clinical course) expressed trace amounts of mutant WASP. In contrast, the XLT patient expressed normal amounts of WASP. Furthermore, cell lines from WAS and XLT patients also markedly differed in F-actin polymerization and alpha-actinin distribution. In particular, severe defects of cytoplasmic F-actin expression and of F-actin-positive microvillus formation, and impaired capping of alpha-actinin, were observed in all patients who lacked WASP. As a whole, the degree of impairment of WASP protein expression in WAS/XLT seems to correlate with anomalies of cytoskeletal organization, strongly supporting a role for WASP in the regulation of F-actin polymerization.


Asunto(s)
Actinas/metabolismo , Proteínas/metabolismo , Síndrome de Wiskott-Aldrich/metabolismo , Actinina/metabolismo , Linfocitos B/metabolismo , Biopolímeros , Western Blotting , Línea Celular Transformada , Transformación Celular Viral , Estudios de Cohortes , Análisis Mutacional de ADN , Expresión Génica , Herpesvirus Humano 4 , Humanos , Técnicas para Inmunoenzimas , Proteínas/genética , Trombocitopenia/genética , Trombocitopenia/metabolismo , Síndrome de Wiskott-Aldrich/genética , Proteína del Síndrome de Wiskott-Aldrich
17.
J Am Acad Dermatol ; 38(6 Pt 2): S87-94, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9631990

RESUMEN

BACKGROUND: Onychomycosis is a prevalent infection of the nail caused primarily by dermatophytes. Fluconazole is active in vitro against the most common pathogens, penetrates into the nail bed, and is clinically effective in the treatment of a wide variety of fungal infections. OBJECTIVE: The purpose of this study was to assess the safety and efficacy of oral fluconazole 150, 300, and 450 mg administered once weekly compared with placebo in the treatment of distal subungual onychomycosis of the fingernail caused by dermatophytes. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled study enrolling 349 patients with onychomycosis of the fingernails. Clinical and mycologic efficacy as well as measures of safety were assessed monthly for a maximum of 9 months of treatment, with additional safety visits occurring at weeks 2 and 6. For inclusion, patients were required to have clinically and mycologically documented onychomycosis of the fingernail caused by dermatophytes with at least 25% involvement of the target fingernail. After end of therapy, patients with improved or cured fingernails entered a blinded 6-month follow-up without drug treatment during which efficacy was assessed every 2 months. Efficacy was assessed by clinical (visual) and mycologic (microscopic and culture) measures. Clinical measures included assessments of the percentage of target nail involvement, measurement of the distance from the nail fold to the proximal onychomycotic border, and signs and symptoms of onychomycosis. RESULTS: Fluconazole was significantly superior to placebo in eradicating clinical and mycologic symptoms of onychomycosis, both at the end of active treatment and at 6 months after treatment (p=0.0001 for all efficacy measures). At the end of therapy, 91% to 100% of patients in the fluconazole groups were judged clinical successes, defined as reduction of the affected area of the target nail to less than 25% or cure, compared with 8% for placebo. Clinical cure rates at end of therapy were 76%, 85%, and 90% for fluconazole 150, 300, and 450 mg, respectively, compared with 3% for placebo. These clinical success and cure rates were largely maintained or improved during follow-up. Clinical relapse in cured patients during the follow-up period was very low (1.5% to 3.3%). Fluconazole demonstrated mycologic eradication rates of 89% to 100% at the end of treatment and 90% to 99% at the end of follow-up; for placebo the rates were 8% and 12%, respectively. CONCLUSION: Fluconazole administered once weekly is safe and effective in eradicating distal subungual onychomycosis of the fingernail caused by dermatophytes.


Asunto(s)
Antifúngicos/administración & dosificación , Antifúngicos/efectos adversos , Fluconazol/administración & dosificación , Fluconazol/efectos adversos , Onicomicosis/tratamiento farmacológico , Adolescente , Adulto , Anciano , Arthrodermataceae/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Dermatosis de la Mano/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
18.
J Am Acad Dermatol ; 38(6 Pt 2): S95-102, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9631991

RESUMEN

BACKGROUND: Fluconazole is a bis-triazole antifungal agent approved for the treatment of oropharyngeal, esophageal, and vaginal candidiasis, serious systemic candidal infections, and cryptococcal meningitis. OBJECTIVE: The purpose of this study was to evaluate three different durations of once-weekly fluconazole for the treatment of onychomycosis of the toenail caused by dermatophytes. METHODS: In a multicenter, randomized, double-blind, parallel, placebo-controlled trial, 384 patients with distal subungual onychomycosis of the toenail received fluconazole, 450 mg once weekly, or placebo for 4, 6, or 9 months. For inclusion, patients were required to have mycologically confirmed distal subungual onychomycosis of the toenail with a large toenail at least 25% clinically affected but having at least 2 mm of healthy nail between the nail fold and the proximal onychomycotic border. Efficacy was assessed by clinical and mycologic (microscopic and microbiologic) measures at screening, at every treatment visit starting at month 3, and at months 2, 4, and 6 after therapy. Observed or volunteered adverse events were recorded and classified at all visits. RESULTS: At the end of treatment, very significantly superior clinical and mycologic results were achieved in all fluconazole groups compared with placebo (p=0.0001). This superiority was largely maintained over 6 months of follow-up. The clinical and mycologic responses of the 9-month treatment duration were significantly superior to the 4- and 6-month durations. Similar percentages of patients in the fluconazole and placebo groups reported adverse experiences for all three durations of the study. CONCLUSION: Results of this study support the efficacy and safety of fluconazole in the treatment of distal subungual onychomycosis of the toenail.


Asunto(s)
Antifúngicos/administración & dosificación , Antifúngicos/efectos adversos , Fluconazol/administración & dosificación , Fluconazol/efectos adversos , Onicomicosis/tratamiento farmacológico , Adolescente , Adulto , Anciano , Arthrodermataceae/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Dermatosis del Pie/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
19.
J Am Acad Dermatol ; 38(6 Pt 2): S110-6, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9631993

RESUMEN

BACKGROUND: Fluconazole has proven to be safe and effective for a variety of superficial and systemic fungal infections. Preliminary analysis of extensive Phase III studies suggests that it is very effective for the treatment of onychomycosis. Its pharmacokinetic properties, including low molecular weight and high water-solubility, suggest a unique ability to penetrate the nail. This feature is likely to account in part for fluconazole's effectiveness in the treatment of onychomycosis. OBJECTIVE: Determinations of plasma and fingernail concentrations of fluconazole were performed as part of a larger study comparing the safety and efficacy of once-weekly fluconazole (150, 300, and 450 mg) to placebo in the treatment of distal subungual onychomycosis of the fingernails caused by dermatophytes. The relationship between fluconazole concentrations and efficacy was also examined. METHODS: Pharmacokinetic studies were performed by means of plasma and fingernail samples from 133 patients, a subset of 349 patients participating in a double-blind, placebo-controlled clinical trial of fluconazole administered in once-weekly doses of 150, 300, or 450 mg until cure of onychomycosis or for a maximum of 9 months. Blood and fingernail samples for pharmacokinetic analysis were taken at baseline, at week 2, and at monthly intervals during the treatment phase of the study. Patients considered clinically cured or improved also participated in a 6-month follow-up study. During this phase, patients were monitored and samples taken every 2 months. RESULTS: Significant amounts of fluconazole were detected in the earliest fingernail samples taken (after 2 weeks of treatment). After two weekly doses, 30% to 33% of steady-state concentrations had been achieved in healthy nails and 22% to 29% in affected nails. Steady state was achieved in 3 to 5 months. Fluconazole concentration in nails as well as plasma followed dose-proportional pharmacokinetics. Nail:plasma ratios in affected nails were 0.4 to 0.6 at 2 weeks and 1.7 to 1.8 at 6 months. Fluconazole concentrations fell slowly after drug discontinuation and were still detectable 4 months after end of treatment. A statistically significant correlation was found between steady-state concentration and clinical and global outcomes. CONCLUSION: Fluconazole rapidly penetrates the fingernail, where it is retained at detectable levels for at least 4 months after drug discontinuation. A significant correlation exists between fluconazole concentration in the fingernails and clinical and global outcomes.


Asunto(s)
Antifúngicos/administración & dosificación , Antifúngicos/farmacocinética , Fluconazol/administración & dosificación , Fluconazol/farmacocinética , Onicomicosis/tratamiento farmacológico , Onicomicosis/metabolismo , Adulto , Anciano , Antifúngicos/sangre , Esquema de Medicación , Femenino , Fluconazol/sangre , Dermatosis de la Mano/tratamiento farmacológico , Dermatosis de la Mano/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Uñas/metabolismo , Factores de Tiempo
20.
Int J Dermatol ; 37(2): 142-4, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9542676

RESUMEN

A 4-week, double-blind, randomized clinical trial, comparing the efficacy and safety of clobetasol propionate emollient cream 0.05% and its vehicle, was conducted at four private dermatology clinics in 81 non-hospitalized patients (> or = 12 years old) with moderate-to-severe atopic dermatitis covering 2% or more of their body surface. All patients had at least one lesion 2 cm or more in diameter. Three signs/symptoms of target lesions (erythema, pruritus, and induration/papulation) were scored by investigators on a scale of 0-3 (in 0.5-point increments; 0 = absent, 1 = mild, 2 = moderate, and 3 = severe); the total of the three scores had to be > or = 6 for patients to qualify for study entry. Patients were excluded if they were immunocompromised, pregnant, or nursing; had skin atrophy, telangiectasia or striae in skin areas to be treated; or had received topical treatments for atopic dermatitis within 1 week prestudy, intramuscular triamcinolone within 6 weeks prestudy, or long-term systemic corticosteroid usage within 6 months prestudy. Patients were randomized in a 1:1 ratio to receive either clobetasol propionate emollient 0.05% twice daily (n = 41), or the emollient vehicle twice daily (n = 40), for 4 weeks. A fingertip unit, equaling approximately 0.5 g in males and 0.43 g in females (enough to cover approximately 2% of the body), was used to measure and apply a thin film of study drug to the affected areas. The efficacy was evaluated by investigators and patients on days 4, 8, 15, and 29 after initiation of therapy, and 2 weeks after the end of treatment (day 43). Investigators performed a physician's gross assessment based on the percentage improvement of the target lesion. They also rated changes from baseline in mean severity scores for six individual signs/symptoms (erythema, pruritus, induration/papulation, lichenification, erosion/oozing/crusting, and scaling/dryness) and for total signs/symptoms according to the severity scoring system described above. Patients rated their response to treatment as excellent, good, fair, poor, or worse. Laboratory assessments were made on days 15, 29, and (if necessary) day 43.


Asunto(s)
Antiinflamatorios/uso terapéutico , Clobetasol/análogos & derivados , Dermatitis Atópica/tratamiento farmacológico , Emolientes/uso terapéutico , Administración Tópica , Adolescente , Antiinflamatorios/administración & dosificación , Antiinflamatorios/efectos adversos , Clobetasol/administración & dosificación , Clobetasol/efectos adversos , Clobetasol/uso terapéutico , Método Doble Ciego , Emolientes/administración & dosificación , Emolientes/efectos adversos , Glucocorticoides , Humanos , Pomadas , Seguridad , Resultado del Tratamiento
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