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3.
Hosp Med ; 65(7): 426-30, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15287348

RESUMEN

This article briefly reviews the commonly used radiological investigations of the renal tract. The intravenous urogram (IVU) is a widely available imaging technique and one of the first-line investigations, yet is often poorly understood by junior medical teams. This article therefore discusses the IVU in detail, and reviews the common pathologies seen using this technique.


Asunto(s)
Enfermedades Renales/diagnóstico , Urografía/métodos , Humanos , Cálculos Renales/diagnóstico por imagen , Enfermedades Renales/diagnóstico por imagen , Neoplasias Renales/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X , Ultrasonografía , Sistema Urinario/anomalías
4.
Clin Exp Allergy ; 34(6): 952-7, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15196285

RESUMEN

BACKGROUND: If monotherapy with an intranasal corticosteroid can alleviate both nasal and ocular symptoms of allergic rhinitis, treatment may be simplified and costs may be reduced. OBJECTIVE: The purpose of this study was to evaluate the efficacy of once-daily fluticasone propionate (FP) aqueous nasal spray 200 microg compared with vehicle placebo and oral loratadine (LOR) 10 mg in reducing ocular symptoms associated with seasonal allergic rhinitis. METHODS: A total of 471 patients received vehicle placebo, LOR, or FP in this multi-centre, double-blind, double-dummy, randomized study. Patients were > or =12 years old with a history of seasonal allergic rhinitis and a positive skin test for a relevant allergen. During the baseline and treatment periods, patients rated the severity of eye itching, tearing, and redness via visual analogue scales that ranged from 0 (no symptoms) to 100 (most severe symptoms). The three ocular ratings were added to derive the total ocular symptom score (TOSS). Patients with a TOSS > or =120 on at least 4 of the 7 days before the randomization visit were enrolled. The primary outcome was the difference between FP and vehicle placebo in the mean change from baseline in the reflective TOSS overall (averaged over the 28-day treatment period). A difference between FP and vehicle placebo of 25.5 was considered clinically significant. RESULTS: The overall mean change from baseline in the TOSS was significantly greater in the FP group compared with vehicle placebo (clinically significant difference of 28.8; P<0.001) and compared with LOR (difference of 16.2; P=0.028). Overall mean (SEM) changes were -59.9 (5.4) for the placebo group, -72.5 (5.4) for the LOR group, and -88.7 (5.3) for the FP group. The FP treatment group also showed significantly greater overall mean changes in ocular itching, tearing, and redness compared with vehicle placebo (P<0.001) and compared with LOR (P< or =0.045). CONCLUSION: Patients treated with intranasal FP had clinically and statistically significant decreases in ocular symptom scores compared with vehicle placebo. Data also suggest that FP reduced ocular symptoms more than or comparable with oral LOR. Patients experiencing ocular symptoms associated with allergic rhinitis may benefit from monotherapy with intranasal FP.


Asunto(s)
Androstadienos/administración & dosificación , Glucocorticoides/administración & dosificación , Rinitis Alérgica Estacional/tratamiento farmacológico , Administración Tópica , Adulto , Aerosoles , Androstadienos/efectos adversos , Androstadienos/uso terapéutico , Método Doble Ciego , Femenino , Fluticasona , Glucocorticoides/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Estudios Prospectivos , Tamaño de la Muestra
5.
Occup Environ Med ; 60(1): 69-75, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12499461

RESUMEN

AIMS: To determine if exposure to dimethylisopropanolamine (DMIPA) and dimethylaminoethanol (DMAE) in a label printing plant was associated with visual disturbances and/or ocular changes. METHODS: Questionnaires, eye examinations (visual acuity, contrast sensitivity at 2.5% and 1.25% contrast, slit lamp biomicroscopy, and pachymetry), and industrial hygiene monitoring for DMIPA and DMAE were performed over a two week period. RESULTS: Eighty nine per cent of line workers reported having experienced blurry vision while at work in the past 12 months, compared to 12.5% of prime workers. A total of 108 full shift personal breathing zone (PBZ) air samples for the amines were collected. The mean time weighted average (TWA) concentration of DMIPA was significantly higher in the line division than in the prime division, as was the mean TWA concentration for total amines. The mean TWA concentration of DMAE was higher in the prime division than the line division. Higher levels of total amines were associated with increased risk of reporting blurry vision, halo vision, and blue-grey vision. The risk of corneal opacity rose with increasing exposure to total amines. The prevalence of corneal opacity also increased with increasing concentration of total amines. Median corneal thickness increased with increasing grades of corneal opacity. There was a statistically significant relation between total amine concentration and increased risk of reduced bilateral visual acuity and 2.5% contrast sensitivity. CONCLUSIONS: Exposure to tertiary amines was associated with blurry, halo, and blue-grey vision, corneal opacity, and decrements in visual acuity and contrast sensitivity at 2.5% contrast.


Asunto(s)
Aminas/efectos adversos , Opacidad de la Córnea/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Visión Ocular/efectos de los fármacos , Humanos , Impresión , Análisis de Regresión , Ventilación
6.
Ann Allergy Asthma Immunol ; 86(3): 286-91, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11289326

RESUMEN

BACKGROUND: The effectiveness of fluticasone propionate (FP) aqueous nasal spray in the treatment of rhinitis has been demonstrated in multiple controlled clinical studies. The onset of therapeutic effect of FP in these clinical trials appears to occur within 12 hours after administration of the initial dose. OBJECTIVE: This article presents an analysis from previous clinical trials that examined the efficacy of intranasal FP in patients with rhinitis to ascertain whether the time to onset of the therapeutic effect of this medication could be determined. METHODS: Completed randomized, double-blind, placebo-controlled studies with FP were evaluated to determine whether onset of effect could be evaluated based on the study designs. A study was deemed acceptable for evaluation of onset of effect if at least one evaluation of the intensity of nasal symptoms was completed within 12 hours after the initial dose of study medication and daily evaluations were made thereafter. Adult patients were included in the onset analysis if they received an initial FP dose of 200 microg. Pediatric patients who received an initial FP dose of 100 microg were also included. Onset of effect was evaluated by 1) examining the timepoints at which statistically significant differences were observed between FP and placebo in mean change from baseline for total nasal symptom score (TNSS); and by 2) using a binary probability model of success/failure to determine statistically significant differences from placebo. RESULTS: Twenty-two studies met the criteria to evaluate onset of therapeutic effect; 3,605 patients with rhinitis received FP and 2,271 patients received placebo. This database represents the largest compilation of data ever assembled to determine the onset of therapeutic effect of a corticosteroid nasal spray. Two studies used a "park design" to examine onset of effect; statistically significant differences in TNSS favoring FP were achieved at hours 2 to 4 and at hour 12, respectively. Using a binary probability model of success/failure for analysis of TNSS in the remaining 20 studies not specifically designed to evaluate onset of effect, numerically greater improvements in TNSS for FP compared with placebo were found in 19 of the 20 studies within 12 hours of the administration of the first dose (P < .001). Pairwise comparisons showed statistically significant improvement for TNSS within 12 hours postdose in five of the studies for FP compared with placebo and in none for placebo compared with FP. CONCLUSIONS: Onset of therapeutic effect occurs within 12 hours, and as early as 2 to 4 hours in some patients, after administration of the first dose of FP aqueous nasal spray.


Asunto(s)
Androstadienos/uso terapéutico , Antialérgicos/uso terapéutico , Antiinflamatorios/uso terapéutico , Rinitis/tratamiento farmacológico , Administración Intranasal , Adolescente , Adulto , Aerosoles/administración & dosificación , Aerosoles/uso terapéutico , Androstadienos/administración & dosificación , Antialérgicos/administración & dosificación , Antiinflamatorios/administración & dosificación , Método Doble Ciego , Fluticasona , Humanos , Modelos Estadísticos , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Tiempo
7.
Genes Chromosomes Cancer ; 31(2): 143-55, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11319802

RESUMEN

Previously we immortalized human, nontransformed prostate epithelial cells with SV40 large T-antigen (SV40TAg) and derived increasingly aggressive sublines from the immortalized line. The progression of the tumorigenic sublines to metastatic capacity was accompanied by the formation of an unbalanced translocation between chromosomes 16 and 19, resulting in loss of 19p and proximal 19q. To test whether the tumorigenic and/or metastatic phenotype was causally related to this genetic alteration, we restored a neo-tagged human chromosome 19 to M12 cells by microcell-mediated transfer and assessed their growth. In vitro, the resultant hybrids grew more slowly in monolayer culture and showed a significant reduction in anchorage-independent growth as compared to M12neo controls. In vivo, all mice (13/13) injected subcutaneously (SC) with control M12neo cells developed tumors after 9-15 days. In contrast, 9/15 mice injected SC with microcell-transferred chromosome 19 hybrid cells failed to form tumors, with 6/15 producing very small tumors after 120 days. Analysis of three of these six tumors showed consistent, new chromosomal changes. Furthermore, in one of the tumors, loss of a chromosome 19 was noted in 40% of the cells. After intraprostatic injections of the hybrid cells, only 2/7 mice developed microscopic tumors, with no metastases. These data suggest the presence of a gene or genes on chromosome 19 that function to suppress growth.


Asunto(s)
Cromosomas Humanos Par 19/genética , Cromosomas Humanos Par 19/metabolismo , Neoplasias de la Próstata/etiología , Neoplasias de la Próstata/genética , Supresión Genética/genética , Animales , Adhesión Celular , Técnicas de Cultivo de Célula , División Celular , Ensayo de Unidades Formadoras de Colonias , Análisis Citogenético , Células Epiteliales/citología , Células Epiteliales/metabolismo , Células Epiteliales/trasplante , Técnicas de Transferencia de Gen , Humanos , Células Híbridas/citología , Células Híbridas/metabolismo , Células Híbridas/trasplante , Inyecciones Subcutáneas , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/trasplante
8.
Arch Otolaryngol Head Neck Surg ; 127(2): 193-9, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11177038

RESUMEN

OBJECTIVE: To evaluate whether 1 year of continuous treatment with intranasal fluticasone propionate would lead to atrophy in the nasal mucosa compared with an active control, oral terfenadine. DESIGN: Prospective, randomized, multicenter, open-label, parallel-group study. SETTING: Two tertiary care academic institutions. PATIENTS: Seventy-five subjects older than 18 years with perennial allergic rhinitis. INTERVENTIONS: Patients received either fluticasone propionate aqueous nasal spray, 200 microg once daily, or terfenadine, 60 mg twice daily, for 1 year. Nasal biopsy specimens were obtained before and after 1 year of treatment and were evaluated for evidence of atrophy. MAIN OUTCOME MEASURES: Epithelial and collagen layer thickness of the nasal mucosa as assessed by light microscopy and the presence and degree of edema, and regularity of collagen fibrils as assessed by electron microscopy. Analyses were performed without knowledge of subject identity or treatment assignment. RESULTS: Neither fluticasone nor terfenadine treatment led to atrophy in the nasal mucosa by clinical or histologic observation. No significant changes from baseline were observed for any assessment of atrophy. In contrast to what would have been expected if atrophy were to occur, mean epithelial layer thickness in the fluticasone group significantly increased compared with terfenadine treatment (P = .03). CONCLUSIONS: Treatment with intranasal fluticasone for 1 year increases the thickness of the nasal epithelium as compared with a year's treatment with terfenadine and does not lead to atrophy in the nasal mucosa. The increased thickness in the fluticasone treatment may represent repair from epithelial damage caused by chronic allergic inflammation.


Asunto(s)
Androstadienos/administración & dosificación , Antialérgicos/administración & dosificación , Antialérgicos/efectos adversos , Antiinflamatorios/administración & dosificación , Antiinflamatorios/efectos adversos , Mucosa Nasal/efectos de los fármacos , Rinitis Alérgica Perenne/tratamiento farmacológico , Rinitis Alérgica Estacional/tratamiento farmacológico , Administración Intranasal , Administración Oral , Adulto , Androstadienos/efectos adversos , Atrofia , Femenino , Fluticasona , Glucocorticoides , Humanos , Masculino , Persona de Mediana Edad , Mucosa Nasal/patología , Estudios Prospectivos , Rinitis Alérgica Perenne/patología , Rinitis Alérgica Estacional/patología , Terfenadina/administración & dosificación
9.
J Fam Pract ; 47(2): 118-25, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9722799

RESUMEN

BACKGROUND: Intranasal corticosteroids and oral antihistamines are both effective in the treatment of seasonal allergic rhinitis, although the therapeutic value of administering the two types of agents concurrently has rarely been evaluated. This study was designed to compared the efficacy, safety, and impact on quality of life of fluticasone propionate aqueous nasal spray (FP ANS), loratadine, FP ANS plus loratadine, and placebo (an aqueous nasal spray plus tablet) in the treatment of seasonal allergic rhinitis during the mountain cedar allergy season in south central Texas. METHODS: Six hundred patients with seasonal allergic rhinitis were treated for 2 weeks with either FP ANS 200 microgram once daily, loratadine 10 mg once daily, the FP ANS and loratadine regimens combined, or placebo in a multicenter, randomized, double-blind, double-dummy, parallel-group study. RESULTS: Clinician- and patient-rated total and individual nasal symptom scores after 7 and 14 days of therapy and overall evaluations were significantly lower (P < .001) in the FP ANS and FP ANS plus loratadine groups compared with the loratadine only and placebo groups. Loratadine was not statistically different from placebo in clinician and patient symptom score ratings nor in overall clinician and patient evaluations. FP ANS plus loratadine and FP ANS monotherapy were comparable in efficacy in almost all evaluations; for some patient-rated symptoms the combination was found superior. Mean score changes in the Rhinoconjunctivitis Quality of Life Questionnaire from baseline to day 14 showed significantly greater improvement (P < .001) in quality of life in the FP ANS group than in the group of patients receiving loratadine only or placebo and no significant benefit was demonstrated in the FP ANS plus loratadine group over the FP ANS monotherapy group. No serious or unusual drug-related adverse events were reported. Combining loratadine with FP ANS did not alter the adverse events profile or frequency.


Asunto(s)
Androstadienos/uso terapéutico , Antiinflamatorios/uso terapéutico , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Loratadina/uso terapéutico , Rinitis Alérgica Estacional/tratamiento farmacológico , Administración Intranasal , Adolescente , Adulto , Anciano , Método Doble Ciego , Combinación de Medicamentos , Femenino , Fluticasona , Glucocorticoides , Humanos , Masculino , Persona de Mediana Edad , Polen/inmunología , Calidad de Vida , Rinitis Alérgica Estacional/inmunología , Texas
10.
Prostate ; 34(4): 275-82, 1998 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9496902

RESUMEN

BACKGROUND: The available human prostate cancer cell lines that are metastatic in athymic nude mice all have complex, highly aneuploid karyotypes. Other prostatic cells immortalized by transforming genes of SV40 or HPV and converted to tumorigenicity by additional genetic manipulation are not reported to be metastatic. METHODS: Tumorigenic sublines of human prostate epithelial cells previously immortalized by transfection with the SV40T antigen gene were obtained by sequential passage in male athymic nude mice. These sublines were evaluated histopathologically for tumorigenicity and metastasis in athymic nude mice after subcutaneous, intraperitoneal, and intraprostatic injection. Each subline was characterized by standard (GTG-banding) cytogenetic and FISH analysis, and RNase protection assays for androgen receptor expression. RESULTS: Two sublines produced metastases in lungs and the diaphragm of most mice after either intraprostatic or intraperitoneal injection. The M2205 subline formed large local tumors after intraprostatic injection. Cytogenetic aberrations present in the metastatic sublines, but not in the tumorigenic, nonmetastatic lines or the parental P69SV40T line, included dup(11)(q14q22), der(16) t (16;19) (q24;q13.1), which resulted in the loss of the short arm and proximal long arm of chromosome 19 (19q13.1-->19pter), and loss of the Y chromosome. None of the sublines expressed the androgen receptor. CONCLUSIONS: These cytogenetically defined, SV40T-immortalized human prostate epithelial cell lines, with distinct biological behaviors in vivo, provide additional tools for the genetic analysis of the emergence of metastatic capacity.


Asunto(s)
Antígenos Transformadores de Poliomavirus , Neoplasias Pulmonares/patología , Metástasis de la Neoplasia , Neoplasias de la Próstata/patología , Células Tumorales Cultivadas , Animales , Línea Celular Transformada , Transformación Celular Viral , Células Epiteliales , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Próstata/citología , Próstata/metabolismo , Neoplasias de la Próstata/genética
11.
Cancer Res ; 57(21): 4699-702, 1997 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-9354424

RESUMEN

Among the aprt mutations induced in confluence-arrested Chinese hamster ovary D422 cells by the topoisomerase II poison amsacrine, there was a reciprocal exchange between the aprt gene and an unrelated sequence, accompanied by a chromosomal translocation at the aprt locus. The breakpoints in both parental sequences were hot spots for amsacrine-stimulated DNA cleavage in vitro, and the novel junctions formed were precisely as expected for a mechanism involving reciprocal exchange of topoisomerase II subunits followed by resealing of the breaks and correction of mismatches in the cohesive ends. The results are consistent with a role for direct subunit exchange in the production of chromosomal translocations by topoisomerase poisons, although more complex models involving double-strand breakage and repair could produce reciprocal exchanges of similar specificity.


Asunto(s)
Adenina Fosforribosiltransferasa/genética , ADN-Topoisomerasas de Tipo II/genética , Reordenamiento Génico/genética , Eliminación de Secuencia , Translocación Genética , Amsacrina/farmacología , Animales , Antineoplásicos/farmacología , Secuencia de Bases , Células CHO/efectos de los fármacos , Mapeo Cromosómico , Cricetinae , Datos de Secuencia Molecular
12.
Proc Natl Acad Sci U S A ; 94(22): 12018-23, 1997 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-9342355

RESUMEN

Chromosomal translocations induced by ionizing radiation and radiomimetic drugs are thought to arise by incorrect joining of DNA double-strand breaks. To dissect such misrepair events at a molecular level, large-scale, bleomycin-induced rearrangements in the aprt gene of Chinese hamster ovary D422 cells were mapped, the breakpoints were sequenced, and the original non-aprt parental sequences involved in each rearrangement were recovered from nonmutant cells. Of seven rearrangements characterized, six were reciprocal exchanges between aprt and unrelated sequences. Consistent with a mechanism involving joining of exchanged double-strand break ends, there was, in most cases, no homology between the two parental sequences, no overlap in sequences retained at the two newly formed junctions, and little or no loss of parental sequences (usually

Asunto(s)
Adenina Fosforribosiltransferasa/genética , Daño del ADN , Recombinación Genética , Translocación Genética , Animales , Secuencia de Bases , Bleomicina/farmacología , Células CHO , Cricetinae , Radicales Libres , Reordenamiento Génico , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Mutagénesis , Mutágenos/farmacología , Análisis de Secuencia de ADN
13.
Ann Allergy Asthma Immunol ; 77(5): 407-15, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8933780

RESUMEN

BACKGROUND: Allergen-induced nasal responses are associated with the recovery of proinflammatory mediators and cytokines. In recent years, a distinct group of chemotactic cytokines, chemokines, has been the focus of intense investigation as to their possible role in the pathogenesis of allergic diseases. Although corticosteroids have been known to be effective in the treatment of allergic diseases, their mechanism(s) of action has not been fully elucidated. OBJECTIVES: To study the effect of topical fluticasone on the recovery of chemokines (IL-8, MIP-1 alpha, and RANTES) and other cytokines (IL-1 beta, IL-6, and GM-CSF) from nasal mucosa following allergen challenge. To correlate the improvement of rhinitis symptoms with cytokine levels during early-phase and late-phase allergic responses. METHODS: A randomized, double-blind, placebo-controlled crossover study of fluticasone propionate, 200 micrograms q d, was performed in ten subjects with allergic rhinitis. Allergen challenge was administered after 1 week of treatment. Nasal secretions were collected immediately after challenge and during the late-phase reactions; symptom scores were recorded simultaneously. Nasal cytokines were assayed by specific ELISA. RESULTS: The allergen challenge caused early-phase and late-phase allergic reactions and increased recovery of IL-1 beta, IL-6, IL-8, RANTES, MIP-1 alpha, and GM-CSF from the nasal mucosa. Intranasal fluticasone inhibited the allergen-induced increase in nasal symptoms. This was associated with decreases in cytokine recovery. A significant correlation was observed between decreases in cytokine levels and in symptom scores after treatment. CONCLUSION: Our results suggest that treatment with topical fluticasone propionate inhibits allergen-induced nasal responses and the associated increase in the production/secretion of chemokines and other proinflammatory cytokines.


Asunto(s)
Alérgenos/efectos adversos , Androstadienos/uso terapéutico , Antiinflamatorios/uso terapéutico , Quimiocinas/metabolismo , Citocinas/metabolismo , Mucosa Nasal/metabolismo , Rinitis Alérgica Estacional/metabolismo , Administración Tópica , Androstadienos/administración & dosificación , Animales , Antiinflamatorios/administración & dosificación , Estudios Cruzados , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Fluticasona , Glucocorticoides , Humanos , Ácaros/inmunología , Mucosa Nasal/efectos de los fármacos , Pruebas de Provocación Nasal , Polen/inmunología , Rinitis Alérgica Estacional/inducido químicamente , Rinitis Alérgica Estacional/tratamiento farmacológico
14.
Biochemistry ; 35(9): 3072-84, 1996 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-8608148

RESUMEN

Bacteriochlorophyll (BChl) structural requirements for formation of the core light-harvesting complex (LH1) and its structural subunit complex were examined by reconstitution with BChl analogs and the alpha- and beta-polypeptides of Rhodospirillum rubrum and Rhodobacter sphaeroides. Comparable results were obtained with most of the BChl analogs and the polypeptides of each bacterium, indicating the conservation of BChl binding sites. These systems showed the following common requirements for formation of the subunit complex and LH1: (1) Mg or a metal of similar size and coordination chemistry (e.g., Zn, Cd, Ni), (2) a bacteriochlorin oxidation state of the macrocyclic ring, (3) a 13(2)-carbomethoxy group, and (4) an intact ring V. Some structural features were not as critically important. For example, the subunit complex and LH1 could be formed with both sets of polypeptides and BChl b, as well as with analogs containing either short (ethanol) or long (phytol) esterifying alcohols. Two derivatives were identified that behave differently with the two sets of polypeptides. The 3-acetyl group is required to form LH1 in both bacteria, although a subunit-type complex was readily formed with [3-vinyl]BChl a and the polypeptides of Rs. rubrum but formed only slightly under special conditions with polypeptides of Rb. sphaeroides. [13(2)-OH]BChl a(p) formed both subunit- and LH1-type complexes with the alpha- and beta-polypeptides of Rb. sphaeroides but not with those of Rs. rubrum. Thus, some subtle differences in the BChl binding sites exist in the LH1 complexes of these two bacteria.


Asunto(s)
Proteínas Bacterianas , Bacterioclorofilas/metabolismo , Complejos de Proteína Captadores de Luz , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Rhodobacter sphaeroides/metabolismo , Rhodospirillum rubrum/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Dicroismo Circular , Sustancias Macromoleculares , Modelos Estructurales , Datos de Secuencia Molecular , Oxidación-Reducción , Unión Proteica , Conformación Proteica , Homología de Secuencia de Aminoácido , Espectrofotometría , Relación Estructura-Actividad
15.
Am J Med Genet ; 57(3): 429-36, 1995 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-7677146

RESUMEN

The heritability and heteromorphic appearance of chromosomal banding patterns induced through in situ digestion with the restriction enzyme AluI were studied by analyzing the chromosomes of 25 monozygotic and 25 dizygotic twin pairs selected at random from a juvenile twin registry. A total of 19 AluI banding variants were found to be heteromorphic, with the pericentromeric region of chromosome 3 and the satellites of chromosome 22 being most and least heteromorphic, respectively. As expected, the correlations of the semi-quantitative scores for each of the chromosomal variants were significantly higher between MZ twin pairs (ranging from 0.48 to 0.95) than DZ twin pairs (ranging from -0.02 to 0.69), suggesting that genetic factors play an important role in their appearance. This finding was confirmed in a model fitting analysis in which the heritabilities of the AluI-induced chromosome variants were found to range from 70 to 96% for 12/13 heteromorphisms studied. These consistent findings are significant in that these variants may be useful for family studies in clinical genetics.


Asunto(s)
Bandeo Cromosómico , Variación Genética , Adolescente , Adulto , Niño , Cromosomas Humanos , Desoxirribonucleasas de Localización Especificada Tipo II , Femenino , Humanos , Cariotipificación , Masculino , Gemelos Dicigóticos , Gemelos Monocigóticos
16.
Int J Cancer ; 58(5): 721-9, 1994 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8077059

RESUMEN

Our primary objectives were to: 1) develop a system for the study of prostatic tumor evolution; and 2) examine the role of the epidermal growth factor/epidermal growth factor receptor (EGF/EGFR) pathway in prostate tumor progression. Adult human prostate epithelial cells previously immortalized by transfection with the SV40 T antigen gene (P69SV40T) produced tumors in only 2/18 mice with a 6 month latency period. Reinjection of cells recovered from these tumors after 1 or 2 cycles of growth in nude mice produced tumors in 2/4 and 2/3 mice with markedly decreased latent intervals of 12, 25, 25 and 25 days each. The chromosomal complement of each tumor was human, consistently pseudodiploid, and retained the Y chromosome. In both anchorage-independent and adherent cell growth assays, EGF stimulated proliferation by approximately 2-fold in both the parental P69SV40T line and the tumor sublines. The tumor sublines expressed less EGFR protein than the parental line, as assessed by Western immunoblotting and flow cytometric analysis. Immunoprecipitation revealed increased production of the 18 and 25 kDa TGF-alpha precursors parallel to decreases in detectable EGFR. The growth of both the parental P69SV40T line and the tumor sublines was inhibited by a neutralizing antibody to TGF-alpha under serum-free defined conditions. Inclusion of the TGF-alpha neutralizing antibody consistently inhibited the proliferation of the tumor sublines more than P69SV40T in both proliferation and [3H]thymidine incorporation assays. This finding suggests that the increased tumorigenicity and decreased latent interval observed among the human prostate tumor cells is partially due to activation of the TGF-alpha/EGFR autocrine network.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Transformación Celular Neoplásica/patología , Receptores ErbB/metabolismo , Neoplasias de la Próstata/patología , Animales , Adhesión Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Humanos , Cariotipificación , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias de la Próstata/microbiología , Factor de Crecimiento Transformador alfa/metabolismo , Células Tumorales Cultivadas
17.
Am J Med Genet ; 47(8): 1218-22, 1993 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-7904793

RESUMEN

We have used 9 conventional RFLPs and 6 dinucleotide repeat polymorphisms on chromosome 21q to demonstrate that 17 of 19 cases of rea(21q21q) were consistent with isochromosomes i(21q) with the remaining 2 being true Robertsonian translocations. Eight of the 17 isochromosomes were of maternal origin and 9 cases were paternally derived. The 2 Robertsonian translocations were both maternally derived. Of the 17 isochromosomes, 7 were dicentric [idic(21q)] and 10 were monocentric [i(21q)]. Both rob(21q21q) were monocentric. Our findings agree with those made in 17 previously published cases of rea(21q21q). The parental origins of the i(21q) were equally divided between maternal (n = 17) and paternal (n = 15) origins. All 4 true rob(21q21q) reported to date are of maternal origin. Collectively, it appears that most homologous rearrangements of chromosome 21 are isochromosomes and only a small proportion are consistent with true Robertsonian translocations.


Asunto(s)
Cromosomas Humanos Par 21 , Síndrome de Down/genética , Translocación Genética , Adulto , Preescolar , Femenino , Humanos , Masculino , Linaje , Polimorfismo de Longitud del Fragmento de Restricción , Prohibitinas
18.
Am J Med Genet ; 43(6): 957-63, 1992 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-1357969

RESUMEN

Cytogenetic heteromorphisms and restriction fragment length polymorphisms were used to assign the parental origins of 30 de novo non-homologous Robertsonian translocations. The balanced and unbalanced translocations studied included 20 rob(14q21q) four rob(13q14q)four rob(15q21q) one rob(13q15q), and one rob(13q21q). Significantly more maternally (26/30) than paternally (4/30) derived de novo translocations were noted and all rob(14q21q) ascertained through unbalanced probands (20/20) were maternal in origin. Interestingly, 12/13 probands who were trisomic and informative for proximal chromosome 21q loci were homozygous for the markers tested. Segregation (2:1) of the Robertsonian translocation into one daughter cell in meiosis I and subsequent failure of the chromosome 21 chromatids to separate in meiosis II may account for our observation of homozygosity for proximal chromosome 21 loci in the majority of de novo rearrangements tested.


Asunto(s)
Translocación Genética , Cromosomas Humanos Par 21 , Citogenética , ADN/genética , Síndrome de Down/genética , Femenino , Humanos , Masculino , Meiosis/genética , Padres , Linaje , Polimorfismo de Longitud del Fragmento de Restricción
19.
Hum Genet ; 86(4): 375-82, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1671850

RESUMEN

The largest class of de novo chromosomal rearrangements in Down syndrome are rea(21q21q). Classically, these rearrangements have been termed Robertsonian translocations, implying an attachment of two different chromosome 21 homologues. Additionally, a Robertsonian translocation between two chromosomes 21 cannot be distinguished from an isochromosome composed of genetically identical arms by cytogenetic analyses. Therefore, we have used molecular techniques to differentiate between true Robertsonian translocations and isochromosomes. Samples were obtained from 12 probands, ascertained for de novo rearrangements between homologous chromosomes 21 [11 rea(21q21q) and 1 rea (21;21)(q22;q22)], their parents (n = 24) and available siblings (n = 7). The parental origins of the de novo rearrangements were assigned using molecular and cytogenetic analyses. Although not statistically significant, there was a two-fold increase in the number of paternally derived de novo rearrangements (n = 8) as compared with maternally derived rearrangements (n = 4). To distinguish between rob(21q21q) and i(21q), we used restriction fragment length polymorphisms (RFLPs) spanning the length of chromosome 21. Using all informative and partially informative RFLPs, we used the method of maximum likelihood to assign the most likely rearrangement definition (i or rob) and parental origin in each family. The maximum likelihood estimates indicated that all rearrangements tested (n = 8) were isochromosomes. C-banding revealed two centromeres in three cases indicating that a U-type exchange occurred between sister chromatids in these rearrangements. Our results suggest that the majority of de novo rea(21q21q) are isochromosomes derived from a single parental chromosome 21.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 21 , Células Cultivadas , Bandeo Cromosómico , Femenino , Humanos , Linfocitos/citología , Masculino , Linaje , Polimorfismo de Longitud del Fragmento de Restricción , Probabilidad , Prohibitinas
20.
Am J Hum Genet ; 37(6): 1049-61, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2934977

RESUMEN

An unusual nucleolar organizer region (NOR) heteromorphism was noted among 13 of 41 parents in whom nondisjunction leading to trisomy 21 was known to have occurred. In contrast, only one of these double NOR (dNOR) variants was found among the 41 normal spouses and none were seen among 50 control individuals. In two dNOR(+) families, a second child with trisomy 21 was conceived. In both families, the extra chromosome in each child was contributed by the parent who carried the dNOR variant and resulted from a recurrent meiosis I error. Our data suggest that the dNOR heteromorphism may play a role in meiotic nondisjunction and could be associated with as much as a 20-fold increased risk for having offspring with trisomy 21.


Asunto(s)
Síndrome de Down/genética , Variación Genética , Región Organizadora del Nucléolo , Niño , Femenino , Tamización de Portadores Genéticos , Humanos , Masculino , Meiosis , No Disyunción Genética , Linaje , Riesgo
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