RESUMEN
The process of enzymatic aging was studied in livers of adult and senescent rats for aldolase B. No "cross-reacting material" was found in livers of 27 to 30-month-old rats, estimated by the ratio aldolase activity-antigen amount. The activity towards the two substrates of aldolase, fructose 1,6-diphosphate and fructose 1-phosphate did not vary in senescent animals. Moreover, other physico-chemical properties of the enzyme such as thermal inactivation, immunological reactivity and Michaelis constant remain unchanged. These results provide arguments against the occurrence of errors in protein synthesis as a cause of aging.
Asunto(s)
Fructosa-Bifosfato Aldolasa/metabolismo , Hígado/enzimología , Envejecimiento , Animales , Femenino , Inmunodifusión , Isoenzimas/metabolismo , Cinética , Hígado/crecimiento & desarrollo , Masculino , Desnaturalización Proteica , Ratas , TemperaturaRESUMEN
A new method for the purification of human erythrocyte uridylyl transferase (UDPglucose: alpha-D-galactose-1-phosphate uridylyltransferase EC 2.7.7.12) is described. It consists of a hydrophobic purification step associated with hydroxyapatite chromatography and provided for the first time a purification of more than 45 000-fold with a high activity (15 I.U/mg) and a yield of 32%. We show that the enzyme is a dimer and has a molecular weight of 88 000. It can be resolved into three bands by isoelectric focusing with an apparent pI between 5.0 and 5.4. It could be shown by steady-state initial rate measurements that the interconversion of the two substrates of human transferase (Gal-1-P and UDP-glucose) follows ping-pong bi-bi kinetics, with Km values of 0.2 and 0.065 mM, respectively.
Asunto(s)
Eritrocitos/enzimología , Nucleotidiltransferasas/sangre , UDP-Glucosa-Hexosa-1-Fosfato Uridiltransferasa/sangre , Humanos , Cinética , Sustancias Macromoleculares , Peso Molecular , Temperatura , UDP-Glucosa-Hexosa-1-Fosfato Uridiltransferasa/aislamiento & purificaciónRESUMEN
We undertook cloning and sequencing of the 5' portion of the human aldolase A gene to elucidate the mechanisms that govern synthesis of its different mRNAs. The sequenced gene is the only active gene in human-rodent fibroblastic somatic hybrids, while the other aldolase A-related sequences are inactive. S1 mapping and primer extension analysis enabled us to demonstrate that three promoter regions were implicated in the initiation of different aldolase A mRNAs, differing only in their 5' non-coding extremities. A distal promoter, N (non-specific), governs the synthesis of a 5' non-coding region of 142 bases composed of two exons, N1 and N2, which are found in a variety of tissues. A median promoter, M (muscle), is only active in skeletal muscle, and initiates the transcription by a 5' non-coding exon of 45 bases. Finally, a proximal promoter, H (housekeeping), contained in a "G + C-rich island", permits transcription of three colinear mRNAs containing 172, 126 or 112 bases of 5' non-coding sequence; their expression seems ubiquitous. These three promoters are arranged in 1.5 X 10(3) base-pairs of DNA. Homologies between rat and human genomic sequences and the absence of homology between promoters or 5' non-coding exons of the same species exclude a recent duplication of the promoter regions.
Asunto(s)
Fructosa-Bifosfato Aldolasa/genética , Regiones Promotoras Genéticas , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Genes , Humanos , Células Híbridas , Datos de Secuencia Molecular , ARN Mensajero/genética , Ratas , Homología de Secuencia de Ácido NucleicoRESUMEN
Pyruvate kinase isozymic changes were studied in the adult hepatocyte cultures, by electrophoretic, kinetic and immunological methods. We were able to maintain parenchymal cells from normal adult rat liver in non-proliferating monolayer cultures up to 10 days. Hepatocytes appeared to contain a dominant PK I type up to 4-5 days of culture. After day 5, PK III type was regularly present with PK I and after 7 days PK III type was always the only isozyme detected in culture. It must be pointed out that, by the Ouchterlony method and sometimes by electrophoresis, concentrated extracts from freshly isolated hepatocytes or starting hepatocyte cultures did also contain Pyruvate kinase PK III type. These results suggest that Pyruvate kinase III is present but partly repressed in the adult parenchymal cells and becomes derepressed in culture.
Asunto(s)
Isoenzimas/aislamiento & purificación , Hígado/enzimología , Piruvato Quinasa/aislamiento & purificación , Envejecimiento , Animales , Células Cultivadas , Represión Enzimática , Feto , Fructosafosfatos/farmacología , Isoenzimas/inmunología , Cinética , Músculos/enzimología , Piruvato Quinasa/inmunología , Piruvato Quinasa/metabolismo , RatasRESUMEN
Uridylyl transferase (UDP glucose: alpha-D-galactose 1 phosphate uridylyl transferase, EC 2.7.7.12) has been purified 1350-fold from human liver to complete homogeneity. The purification procedure involved ammonium sulfate fractionation, batch treatment, chromatography on DEAE-cellulose, hexylagarose and hydroxylapatite. The specific activity of the homogeneous enzyme was 27 units/mg protein. The liver enzyme was compared to the red cell enzyme previously purified by us. The liver enzyme was similar to the red cell enzyme with respect to subunit molecular weight, kinetic studies and immunological properties. Differences in electrophoretic behaviour were found: the liver transferase has a more basic pI (between 5.5 and 5.8) than that of the erythrocyte enzyme (pI between 5.0 and 5.45). It is very likely that the liver uridylyl transferase and the red blood cell transferase are the same enzymes with post-translational modifications.
Asunto(s)
Eritrocitos/enzimología , Hígado/enzimología , Nucleotidiltransferasas/aislamiento & purificación , UDP-Glucosa-Hexosa-1-Fosfato Uridiltransferasa/aislamiento & purificación , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Humanos , Focalización Isoeléctrica , Cinética , Peso Molecular , UDP-Glucosa-Hexosa-1-Fosfato Uridiltransferasa/sangreRESUMEN
Forty patients with placenta accreta, increta, or percreta are presented. Clinical features revealed an average age of 29.5 years and an average parity of 3-2-1. Twenty-five had no antepartum complications. Nine were admitted with silent hemorrhage, of which 6 had a total placenta previa and 1 a low-lying previa. Postpartum hemorrhage occurred in 39% with an associated perinatal mortality of 25% and 1 maternal death. Histopathologic evaluations revealed the predominant factor to be an absent decidua. Etiologic in decidual deficiency was a previous cesarean section (12 patients). Therapy consisted of total abdominal hysterectomy in 38 patients.
Asunto(s)
Placenta Accreta/complicaciones , Adolescente , Adulto , Decidua/anomalías , Femenino , Humanos , Histerectomía , Placenta Accreta/etiología , Placenta Accreta/patología , Placenta Accreta/cirugía , Hemorragia Posparto/etiología , Embarazo , Hemorragia Uterina/etiologíaRESUMEN
OBJECTIVE: To evaluate endocervical curettage (ECC) and cone margin involvement in the management of adenocarcinoma in situ of the cervix. METHODS: Forty-two women with adenocarcinoma in situ without any associated invasive component underwent 49 cervical conizations. The ECC, cone margin involvement, and residual endocervical glandular disease were evaluated in a retrospective descriptive study. RESULTS: The patients ranged from 18 to 65 years old, with a median of 34 years and a mean of 37 years. Nineteen of 42 (45%) of the women presented with initial cervicovaginal cytology suggesting endocervical glandular abnormality. Twenty-seven patients (64%) had mixed lesions of adenocarcinoma in situ and squamous dysplasia noted in their cervical biopsy, conization, or hysterectomy specimens. Forty ECCs were performed at colposcopy or immediately after conization; 28 patients with ECCs subsequently underwent conization, and 12 underwent hysterectomy. Residual adenocarcinoma in situ was found in 18 (67%) of the 27 patients with negative ECCs and in ten of 13 women with positive ECCs. Residual adenocarcinoma in situ was found in two of seven patients with negative cone margins and seven of ten patients with positive margins. CONCLUSION: We found that negative ECCs and uninvolved cone margins in patients with cervical adenocarcinoma in situ were not reassuring of the absence of residual endocervical glandular disease in subsequent surgical specimens. Conservative management and subsequent surveillance of adenocarcinoma in situ should be undertaken with caution.
Asunto(s)
Adenocarcinoma/patología , Carcinoma in Situ/patología , Cuello del Útero/patología , Conización , Dilatación y Legrado Uterino , Neoplasias Primarias Múltiples/patología , Neoplasias del Cuello Uterino/patología , Adenocarcinoma/cirugía , Adolescente , Adulto , Anciano , Carcinoma in Situ/cirugía , Cuello del Útero/cirugía , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Neoplasia Residual , Neoplasias Primarias Múltiples/cirugía , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Neoplasias del Cuello Uterino/cirugíaRESUMEN
A clinical and histopathologic study of material from a series of 17 patients with basal cell carcinoma of the vulva are reviewed. The tumors occurred primarily in elderly patients (average age, 59 years), the majority of whom were Causasian. Presenting symptomatology consisted primarily of pruritus vulvae and/or the presence of a vulvar mass (79%) of long duration (average, 6 years, 7 months). The lesions were described grossly as ulcerations or masses located on the anterior labium majus. Etiologies were indeterminate although 2 patients had previously received vulvar irradiation. Therapy consisted primarily of wide local excision and was effective in that follow-up studies in 16 patients revealed no deaths attributable to basal cell carcinoma. These data indicate that basal cell carcinoma is a locally invasive nonmetastasizing tumor best treated by wide local excision providing the tumor edge does not extend to the margin of excision.
Asunto(s)
Carcinoma Basocelular , Neoplasias de la Vulva , Adulto , Factores de Edad , Anciano , Población Negra , Carcinoma Basocelular/patología , Carcinoma Basocelular/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Paridad , Neoplasias de la Vulva/patología , Neoplasias de la Vulva/cirugía , Población BlancaRESUMEN
BACKGROUND: Periumbilical extension of midline incision often results in an irregular, unaesthetic scar with beveled edges. TECHNIQUE: An Allis clamp is placed at the lateral margin of the umbilicus with subsequent medial traction. This straightens the proposed periumbilical incision, resulting in a symmetrical scar. EXPERIENCE: We have used this technique extensively over the past several years with excellent results and no adverse sequelae. CONCLUSION: This simple technique results in the symmetrically curvilinear, nonbeveled periumbilical extension of a midline incision.
Asunto(s)
Músculos Abdominales/cirugía , Procedimientos Quirúrgicos Ginecológicos/métodos , Femenino , Humanos , OmbligoRESUMEN
OBJECTIVE: To evaluate the clinical and pathologic presentation of mature cystic teratomas and the trends in management over a 14-year study period. METHODS: Tumor registry data and medical records between January 1, 1975 and December 31, 1989 were analyzed with respect to patient age, tumor size, bilaterality, malignant transformation, and treatment. RESULTS: Five hundred seventy-three tumors were removed from 517 patients. The median and mean (+/- standard deviation) age was found to be 30 and 32 +/- 11.3 years, respectively. Three hundred ten (60%) of the patients were asymptomatic. The mean tumor size was 6.4 +/- 3.5 cm. The bilaterality rate was 10.8%. The rate of torsion was 3.5%; larger tumors underwent torsion more frequently than smaller tumors (P = .029). The rate of malignant transformation was 0.17%. The mean cyst diameter for patients undergoing cystectomy was 5.7 +/- 2.4 cm; for oophorectomy, 8.0 +/- 4.1 cm; and for hysterectomy, 6.1 +/- 3.8 cm. Oophorectomies were performed for larger tumors when compared to cystectomies (P = .01). The number of hysterectomies was stable throughout the study period, whereas the number of oophorectomies decreased and the number of cystectomies increased markedly. Contralateral ovarian biopsy was common (48.5%) early in the study period. By 1989, the biopsy rate was less than 1%. CONCLUSIONS: We found the prevalence rates of symptomatic tumors, torsion, and malignant degeneration to be less than those previously reported by most other investigators. In addition, there has been an important change over the past 14 years in the management of these neoplasms, with an increased tendency for ovarian preservation, as evidenced by the more frequent use of cystectomy and a decrease in contralateral ovarian biopsy.
Asunto(s)
Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/patología , Teratoma/epidemiología , Teratoma/patología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Biopsia/estadística & datos numéricos , Biopsia/tendencias , Transformación Celular Neoplásica , Niño , Cistectomía/estadística & datos numéricos , Cistectomía/tendencias , Femenino , Humanos , Histerectomía/estadística & datos numéricos , Histerectomía/tendencias , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Ováricas/cirugía , Ovariectomía/estadística & datos numéricos , Ovariectomía/tendencias , Prevalencia , Estudios Retrospectivos , Teratoma/cirugía , Anomalía TorsionalRESUMEN
By isoelectrofocusing in thin-layer acrylamide-ampholine gel, normal human aldolase B has been resolved into 5 bands. Moreover we were able to specifically stain (after isoelectrofocusing) the mutated aldolase B in livers with hereditary fructose intolerance, and to show that only the 3 most anodic bands are seen. Some different hypotheses are discussed to account for the microheterogeneity of the normal aldolase B, and for the different isoelectrofocusing pattern found in livers with hereditary fructose intolerance.
Asunto(s)
Errores Innatos del Metabolismo de los Carbohidratos/enzimología , Intolerancia a la Fructosa/enzimología , Fructosa-Bifosfato Aldolasa/metabolismo , Hígado/enzimología , Intolerancia a la Fructosa/genética , Fructosa-Bifosfato Aldolasa/inmunología , Humanos , Focalización IsoeléctricaRESUMEN
We retrospectively analyzed 77 patients with stage II endometrial carcinoma treated with standard regimens of preoperative radiotherapy (RT) and surgery (S). The age range was 31-74 years with a median of 56.3 years. Thirty-three patients received 40 Gy whole pelvis RT followed by either radical or modified radical hysterectomy. Forty-four patients received 50 Gy whole pelvis RT and sequential intrauterine and intravaginal cesium-137 brachytherapy followed by a simple hysterectomy. Median follow-up was 111 months. No patient was lost to follow-up. The overall 5-year actuarial survival was 78%. There was no significant difference between the two treatment groups. Several prognostic variables were analyzed. Those with histologic grade I and II had 5-year survival of 89% and 83%, respectively, compared to 62% for grade III (P =0.045). The 5-year survival for microscopic cervical involvement was 87% compared to 59% for gross involvement (P= 0.008). Patients with negative or microscopic residual tumor in the surgical specimen and those with negative lymph nodes had less risk of treatment failure. Local failure occurred in only 9%. Major complications (3%) were seen only in the radical surgery group. Combined preoperative RT and S provide high cure rates with minimal complications for patients with stage II endometrial carcinoma. Patients with adverse prognostic factors are candidates for trials of more aggressive local and systemic therapy.
RESUMEN
Mitral valve prolapse is usually a benign condition, however, serious complications have been reported to be associated with it. A report of retinal artery occlusion associated with mitral valve prolapse and pregnancy is presented.
Asunto(s)
Embolia/complicaciones , Prolapso de la Válvula Mitral/complicaciones , Complicaciones Cardiovasculares del Embarazo , Oclusión de la Arteria Retiniana/etiología , Arteria Retiniana , Adulto , Aspirina/uso terapéutico , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/etiología , Anticonceptivos Orales/efectos adversos , Dipiridamol/uso terapéutico , Quimioterapia Combinada , Femenino , Humanos , EmbarazoRESUMEN
Extrarenal Wilms' tumors (nephroblastomas) are considered rare, with only 36 cases reported to date. A primary Wilms' tumor of the uterus has been reported on two previous occasions. A third case is presented and the histologic features and histogenesis of the tumor discussed.
Asunto(s)
Neoplasias Uterinas/patología , Tumor de Wilms/patología , Adulto , Femenino , Humanos , Histerectomía , Neoplasias Uterinas/cirugía , Tumor de Wilms/cirugíaRESUMEN
Three cases of sacrococcygeal teratoma of the neonate occurred during a two-year period in which approximately 6,000 live births occurred in our hospital. Two infants were delivered vaginally and one by cesarean section. One infant underwent immediate surgery and survived, whereas the other two were in too poor condition to warrant surgery. Early excision is the treatment of choice; radiotherapy and chemotherapy are not effective in the malignant variety of sacrococcygeal lesion.