RESUMEN
Despite the importance of relaxin to normal parturition in various species and its potential as an etiological agent in preterm delivery in women, knowledge regarding the mechanisms by which relaxin alters cervical connective tissue is extremely limited. An established in vitro model for human pregnancy cervix, human lower uterine segment fibroblasts, was used to determine the effects of relaxin as well as those of progesterone on the expression of matrix metalloproteinases and tissue inhibitor of metalloproteinase-1. The results demonstrate that relaxin is a positive regulator of matrix metalloproteinase expression, as it stimulates the expression of procollagenase protein and mRNA levels, stimulates prostromelysin-1 protein and mRNA levels, and inhibits tissue inhibitor of metalloproteinase-1 protein expression. Stimulation of procollagenase and prostromelysin-1 expression by relaxin does not involve phorbol-12-myristate-13-acetate- sensitive PKCs. Relaxin-stimulated tyrosine phosphorylation of the putative receptor and inhibition by a receptor tyrosine kinase inhibitor suggest that the relaxin receptor is probably a tyrosine kinase receptor. Inhibition of c-Raf protein expression using an antisense oligonucleotide inhibits relaxin regulation of matrix metalloproteinase and tissue inhibitor of metalloproteinase-1, suggesting that a signaling pathway involving c-Raf kinase mediates relaxin action.
Asunto(s)
Fibroblastos/enzimología , Metaloproteinasas de la Matriz/metabolismo , Proteínas Tirosina Quinasas/fisiología , Relaxina/farmacología , Transducción de Señal , Útero/enzimología , Células Cultivadas , Colagenasas/metabolismo , Inhibidores Enzimáticos/farmacología , Precursores Enzimáticos/metabolismo , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Inhibidores de la Metaloproteinasa de la Matriz , Metaloendopeptidasas/metabolismo , Fosforilación/efectos de los fármacos , Embarazo , Progesterona/farmacología , Proteína Quinasa C/fisiología , Proteínas Proto-Oncogénicas c-raf/fisiología , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Relaxina/fisiología , Transducción de Señal/fisiología , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Tirosina/metabolismo , Útero/citología , Útero/efectos de los fármacos , Útero/metabolismoRESUMEN
OBJECTIVE: To determine the incidence of early-pregnancy bleeding and spontaneous abortion (SAB) after various treatments for infertility and to assess whether bleeding is predictive of SAB. DESIGN: An historic cohort study of women who conceived after various treatments. SETTING: Hospital-based private practice. PATIENT(S): We studied 418 patients in whom 500 consecutive clinical pregnancies occurred. INTERVENTION(S): Patients were grouped according to the method of conception: ovulation induction, IVF, and other. The latter category included interventions not requiring ovulation induction, such as surgery and insemination. A fourth group of subjects who conceived independently of treatment was used as the control. MAIN OUTCOME MEASURE(S): Bleeding and pregnancy outcome (SAB, ectopic pregnancy, or ongoing pregnancy). RESULT(S): Rates of SAB did not differ among the treatment groups. SAB occurred significantly more often after bleeding than when bleeding did not occur (30.8% versus 19.8%, respectively). Bleeding was predictive of SAB only in patients <35 years old (odds ratio 2.4). CONCLUSION(S): Infertile women who conceive after reproductive therapy are not at increased risk for SAB compared with women who conceive naturally. There appears to be no association between previous diagnosis or treatment and the occurrence of SAB in previously infertile women. Bleeding is associated with a twofold relative risk of SAB.
Asunto(s)
Aborto Espontáneo/etiología , Infertilidad Femenina/terapia , Hemorragia Uterina/complicaciones , Estudios de Cohortes , Bases de Datos Factuales , Femenino , Fertilización In Vitro , Humanos , Infertilidad Femenina/complicaciones , Inducción de la Ovulación , Embarazo , Resultado del Embarazo , Estudios RetrospectivosRESUMEN
Obesity and diet affect the incidence and severity of various types of cancer, including colon cancer. It is not known whether obesity, independent of diet, is a risk factor for colon adenocarcinoma. We used azoxymethane (AOM) to induce colon cancer in mature genetically obese male Zucker rats (fa/fa) on low-fat crude diet (LFC, 10% fat) and their lean counterparts (Fa/fa and Fa/fa) on high-fat crude diet (HFC, 40% fat) for three months. At death visible tumors, histopathology, and colonic aberrant crypt (AC) formation were studied by blinded investigators. At death the obese animals were heavier (719 +/- 19 g; mean +/- SEM) than lean animals regardless of diet or genotype (Fa/fa-LFC:451 = 6 g; Fa/fa-HFC:441 +/-10 g; Fa/Fa-HFC:412 +/- 9 g; P < 0.001 vs fa/fa by ANOVA). All AOM-treated rats developed AC, compared to none of the saline-injected controls. Macroscopic adenocarcinoma developed in 8/9 obese rats on LFC (P < 0.001), compared to none in lean rats regardless of diet. Obese rats had significantly more AC (876 +/- 116) than any of the lean rats (Fa/fa-LFC:550 +/- 99; Fa/fa-HFC:325 +/- 37; Fa/Fa-HFC:360 +/- 36; P < 0.05 vs fa/fa). We conclude that obesity more than exposure to high-fat diet was associated with colon carcinogenesis in these rats.
Asunto(s)
Adenocarcinoma/patología , Neoplasias del Colon/patología , Obesidad/patología , Adenocarcinoma/inducido químicamente , Animales , Azoximetano , Transformación Celular Neoplásica/inducido químicamente , Transformación Celular Neoplásica/patología , Neoplasias del Colon/inducido químicamente , Dieta con Restricción de Grasas , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Masculino , Ratas , Ratas Zucker , Factores de RiesgoRESUMEN
Two siblings who were found to have deficiency of glutaryl-CoA dehydrogenase were identified by the presence of large amounts of 3-hydroxyglutaric acid in the urine. Patients with this disease, termed glutaric acidemia or glutaric acidemia Type I, usually present with large amounts of glutaric acid in the urine, and amounts of 3-hydroxyglutaric acid found are less. Patients were ataxic and dystonic. Intelligence was normal. 3-Hydroxyglutaric acid in the urine was quantified by organic acid analysis via gas chromatography mass spectrometry (GCMS) and by stable isotope-dilution (internal standard) GCMS. Glutaryl-CoA dehydrogenase activity in cultured fibroblasts was found to be 2% of the control level. The nature of the mutations was identified, and both patients were found to be compound heterozygotes for R227P, which changed an arginine to a proline, and E365K, which changed a glutamate to a lysine.
Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/genética , Glutaratos/orina , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Oxidorreductasas/deficiencia , Errores Innatos del Metabolismo de los Aminoácidos/orina , Secuencia de Bases , Niño , Cartilla de ADN , Femenino , Cromatografía de Gases y Espectrometría de Masas , Glutaril-CoA Deshidrogenasa , Humanos , Lactante , Masculino , Oxidorreductasas/genética , Estándares de ReferenciaRESUMEN
BACKGROUND: The optimal treatment of common bile duct (CBD) stones is controversial, and depends on local expertise, the patient's medical condition and the time of diagnosis. Current practice entails a wide variation in the duration of leaving T tubes in place, anywhere from 7 to 30 days, and in the time to postoperative cholangiogram. Here we present a new technique for T-tube placement and management of secondary or retained CBD calculi that reduces T-tube duration to
Asunto(s)
Neoplasias del Conducto Colédoco/cirugía , Drenaje/métodos , Adulto , Drenaje/instrumentación , Femenino , Humanos , Intubación , Masculino , Persona de Mediana EdadRESUMEN
Glutaric acidemia type I (GA1) is caused by mutations in the gene encoding the enzyme glutaryl-CoA dehydrogenase (GCD). Sixty-three pathogenic mutations identified by several laboratories are presented, 30 of them for the first time, together with data on expression in Escherichia coli and relationship to the clinical and biochemical phenotype. In brief, many GCD mutations cause GA1, but none is common. There is little if any relationship between genotype and clinical phenotype, but some mutations, even when heterozygous, seem especially common in patients with normal or only minimally elevated urine glutaric acid.
Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/genética , Glutaratos/sangre , Mutación , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Oxidorreductasas/genética , Genotipo , Glutaril-CoA Deshidrogenasa , Humanos , FenotipoRESUMEN
The structure of the human glutaryl coenzyme A dehydrogenase (GCD) gene was determined to contain 11 exons and to span approximately 7 kb. Fibroblast DNA from 64 unrelated glutaric acidemia type I (GA1) patients was screened for mutations by PCR amplification and analysis of SSCP. Fragments with altered electrophoretic mobility were subcloned and sequenced to detect mutations that caused GA1. This report describes the structure of the GCD gene, as well as point mutations and polymorphisms found in 7 of its 11 exons. Several mutations were found in more than one patient, but no one prevalent mutation was detected in the general population. As expected from pedigree analysis, a single mutant allele causes GA1 in the Old Order Amish of Lancaster County, Pennsylvania. Several mutations have been expressed in Escherichia coli, and all produce diminished enzyme activity. Reduced activity in GCD encoded by the A421V mutation in the Amish may be due to impaired association of enzyme subunits.
Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Oxidorreductasas/genética , Errores Innatos del Metabolismo de los Aminoácidos/epidemiología , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Células Cultivadas , Escherichia coli/genética , Fibroblastos/enzimología , Glutaratos/metabolismo , Glutaril-CoA Deshidrogenasa , Humanos , Pennsylvania , Mutación Puntual , Polimorfismo Genético , Análisis de Secuencia de ADNRESUMEN
Current evidence suggest an important role for increased repair of drug-induced DNA damage as one of the major mechanisms involved in tumor cell resistance to cis-DDP. In this study, we examined the DNA repair capacity and the activities of three DNA repair related proteins, namely, DNA polymerases alpha and beta, and total DNA ligase in cells of a malignant oligodendroglioma obtained from a patient before therapy and compared it with those of a specimen of the tumor acquired after the patient had failed cis-DDP therapy. DNA repair capacity was quantitated as the extent of reactivation of the chloramphenicol-O-acetyltransferase (CAT) gene in a eukaryotic expression vector that had been damaged and inactivated by prior treatment with cis-DDP and then transfected into the tumor cells. The extent of DNA-platinum adduct formation in the expression vector was determined by flameless atomic absorption spectrometry. The level of cis-DDP resistance of cells of the two tumors was determined with the capillary tumor stem cell assay. We observed a 2.8-fold increased capacity to repair Pt-DNA adducts and reactivate the CAT gene in cells of the tumor obtained after cis-DDP therapy, compared to cells of the untreated tumor. This was associated with increases of 9.4-fold and a 2.3-fold, respectively, in DNA polymerase beta and total DNA ligase activities in cells of the treated tumor. At 5 microM cis-DDP, there was a 5.9-fold increase in the in vitro cis-DDP resistance of post-therapy tumor cells relative to cells of the untreated tumor.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Cloranfenicol O-Acetiltransferasa/genética , Cisplatino/farmacología , ADN Ligasas/metabolismo , Reparación del ADN/efectos de los fármacos , ADN Polimerasa Dirigida por ADN/metabolismo , Glioma/enzimología , Línea Celular , Cisplatino/uso terapéutico , Daño del ADN/efectos de los fármacos , ADN Polimerasa I/metabolismo , ADN Polimerasa II/metabolismo , Resistencia a Medicamentos , Glioma/tratamiento farmacológico , Glioma/genética , Humanos , TransfecciónRESUMEN
Our objective was to evaluate and compare the efficacy and mechanisms of co-culturing mouse embryos with Vero cells in both Dulbecco's modified Eagle's medium/Ham's F12 (DMEM/F12) and human tubal fluid (HTF) culture medium. Two-cell CB6F1 mouse embryos were cultured either in the presence of Vero cells (group A) or in culture medium alone (group B). In DMEM/F12 significantly more morulae developed in group A than in group B on day 3 (91 versus 23%; P less than 0.01). In contrast, the mouse embryos grew rapidly in HTF and significant differences were noted only in later embryonic stages (on day 5; 86% and 50%, P less than 0.01 of group A and B respectively, hatching or hatched). Similar experiments using DF1 and ICR mouse strains also revealed enhanced embryo development in the presence of Vero cells. To determine whether the embryo-enhancing effects of Vero cells were due to the removal of toxins or to the secretion of embryotrophic factors, ICR mouse embryos were cultured in fresh media with cells (group A), without cells (group B) and in cell-free conditions using cell-conditioned media which were obtained in the presence (group C) or absence (group D) of embryos. These results demonstrated that completion of hatching was highest (52%; P less than 0.01) in group A after 6 days in culture. There were no significant differences between groups B, C and D (rates of total hatching 18, 17 and 17%, respectively). It is concluded that Vero cells improve the development of mouse embryos and this is likely to be due to removal of substances inhibitory to development.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Embrión de Mamíferos , Técnicas de Cultivo de Órganos/métodos , Células Vero/metabolismo , Animales , Medios de Cultivo , Ratones , Toxinas Biológicas/metabolismoRESUMEN
gamma-L-glutamyl-L-cysteinylglycine (GSH) has been shown to inactivate 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and quench DNA crosslink precursors of BCNU. Because of the central role of 2-chloroethyl-nitrosoureas in brain tumor chemotherapy, we investigated the intracellular GSH content and the expression of specific glutathione-S-transferases (GSTs) in three human malignant astrocytoma cell lines (UWR1, UWR2, and UWR3) of varying BCNU resistance to determine the interrelationship of these parameters with brain tumor BCNU resistance. GSH was assayed by ion-exchange high performance liquid chromatography after derivatization with 1-fluoro-2,4 dinitrobenzene. Both bulk and specific GST (acid, near-neutral, and basic) activities were examined using substrates that show high specificities to the different GSTs. Western blot analyses with antisera against GST-alpha, -mu, and -tau subunits were also performed on partially purified GST from the cells of each cell line. The results showed GSH content of 91, 46.5, and 28.3 nmol GSH/mg protein for UWR1, UWR2, and UWR3, respectively. Bulk GST activity (with 1-chloro-2,4-dinitrobenzene as substrate) also correlated with increasing BCNU resistance. Of the three GST classes examined by both substrate specificities and Western blotting, only the expression of the acidic form, GST-tau, correlated significantly with the rank order of BCNU resistance of the cell lines. GST-mu and -alpha were present in only trace amounts in all three cell lines.
Asunto(s)
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Carmustina/farmacología , Glutatión Transferasa/metabolismo , Glutatión/metabolismo , Astrocitoma/enzimología , Astrocitoma/patología , Western Blotting , Neoplasias Encefálicas/enzimología , Neoplasias Encefálicas/patología , Cisplatino/farmacología , ADN de Neoplasias/efectos de los fármacos , Resistencia a Medicamentos , Electroforesis en Gel de Poliacrilamida/métodos , Glutatión/análogos & derivados , Disulfuro de Glutatión , Humanos , Dodecil Sulfato de Sodio , Especificidad por Sustrato , Células Tumorales CultivadasRESUMEN
The production of DNA interstrand crosslinks (ISC) by BCNU and other bifunctional alkylators and the effects of these drugs on the repair of radiation-induced DNA-single strand breaks (SSB) were studied in two human glioblastoma used to assess both DNA-ISCs and DNA-SSBs. BCNU-treated UWR2 and UWR3 cells showed a significant BCNU dose-dependent increase in radiation-induced DNA-SSBs at 6 hrs post-drug treatment, and at 100 microM BCNU DNA-ISC was completely masked in UWR2 cells. There was no enhancement of radiation-induced DNA-SSBs in both cell lines after treatment with cis-DDP, CHZ, or MNU. In the capillary clonogenic cell assay, UWR2 cells were 3.2 times more resistant than UWR3 cells; 0(6)-methylguanine-DNA methyltransferase activity was also 1.8 times higher in UWR2 than in UWR3. Our data suggest caution in the use of the standard alkaline elution technique (with 6 hrs between drug exposure and irradiation) to measure BCNU-induced DNA-ISC induction in highly BCNU-resistant cell lines. We provide evidence that the synergism between BCNU and radiation in the generation of DNA-SSBs is the result of low DNA-SSB repair capacity of the cells, and is further potentiated by the carbamoylating action of BCNU.
Asunto(s)
Carmustina/farmacología , Daño del ADN , Reparación del ADN , ADN de Neoplasias/efectos de los fármacos , Alquilantes/farmacología , Línea Celular , Cisplatino/farmacología , Reactivos de Enlaces Cruzados , ADN de Neoplasias/genética , ADN de Neoplasias/efectos de la radiación , Resistencia a Medicamentos , Glioblastoma , Humanos , Cinética , Estreptozocina/análogos & derivados , Estreptozocina/farmacologíaRESUMEN
Fifteen patients with painful total hip prostheses were referred for nuclear medicine and roentgenographic arthrography studies to exclude loosening of the acetabular and/or the femoral component. A new radioisotopic technique suitable for the evaluation of both components was developed using dual-isotope single-photon tomography with 99mtechnetium methylene diphosphonate bone imaging and indium-111 diethylenetriaminepentacetic acid arthrography. Thirteen of the 15 subjects were subsequently treated with additional surgery. The surgical findings were compared with the nuclear medicine and roentgenographic results. The overall diagnostic accuracy of both arthrographic procedures was approximately 80%, but the roentgenographic arthrogram was more sensitive and the radionuclide arthrogram was more specific.
Asunto(s)
Artrografía/métodos , Prótesis de Cadera , Radioisótopos de Indio , Dolor Postoperatorio/diagnóstico por imagen , Ácido Pentético , Anciano , Femenino , Humanos , Yotalamato de Meglumina , Masculino , Persona de Mediana Edad , Falla de Prótesis , Cintigrafía , Medronato de Tecnecio Tc 99mRESUMEN
Sixty patients with active upper gastrointestinal bleeding were randomized to received either continuous intravenous infusions of vasopressin (29 patients) or placebo (31 patients) at a rate of 40 U/h. Six hours after beginning the study, 13 patients in the vasopressin group and 11 in the placebo group] had ceased bleeding (p = 0.46). By 24 hours. 17 patients in the vasopressin group and 14 in the placebo group had stopped bleeding (p = 0.30). Restriction of the analysis to patients bleeding from varices showed no advantage with vasopressin treatment after 6 or 24 hours. No consistent trend favoring use of vasopressin to stop hemorrhage was noted during the 30-month study period. There was little difference between the two groups in the number of patients needing surgery (13 on vasopressin, 18 on placebo; p = 0.30) or the number of deaths (eight on vasopressin, 11 on placebo; p = 0.51); the transfusion requirement was the same. In our patients, a continuous intravenous infusion of vasopressin neither controlled bleeding nor altered outcome.