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1.
Rev. chil. obstet. ginecol. (En línea) ; 86(2): 137-151, abr. 2021. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1388643

RESUMO

OBJETIVO: Determinar el tiempo que requiere una curva de aprendizaje para diagnóstico ecográfico específico histopatológico en masas anexiales basándonos en cálculos estadísticos no influidos por la prevalencia según diferentes grados de experiencia. MÉTODOS: Estudio observacional, descriptivo, transversal. Se estudiaron imágenes de 108 masas anexiales. La prueba estándar de oro fue el reporte histopatológico definitivo. Se comparó el rendimiento diagnóstico de 4 examinadores con la siguiente experiencia en diagnóstico ecográfico de patología anexial: A > 20 años, B ≤ 20 hasta > 10 años, C ≤ 10 hasta > 5 años y D ≤ 5 años, analizando solo imágenes y sin datos clínicos de las pacientes, para emitir un diagnóstico específico a libre escritura. RESULTADOS: Prevalencia de masas malignas 17,2 % (15/87). Nivel de confianza en los examinadores se consideró según falta de respuesta diagnóstica: alto (<6 %) con experiencia de más de 10 años y moderado a bajo ≤ 10 años. Examinadores con más de 5 años siempre mostraron likelihood ratio positivo mayor a 10, exactitud diagnóstica mayor a 90 % y Odds ratio diagnóstica mayor a 46, no así para examinador con menor tiempo de experiencia, quién presentó resultados con mala utilidad clínica. El cambio de probabilidad de acierto específico pre-test a post-test mejoró consistentemente con los años de experiencia. CONCLUSIÓN: Se necesitarían más de 10 años de experiencia con especial dedicación a ecografía ginecológica avanzada para un rendimiento diagnóstico específico deseado junto con alta confianza en ecografía de masas anexiales.


OBJECTIVE: To determine the time required for a learning curve of histopathological specific ultrasound diagnosis in adnexal masses based on statistical calculations not influenced by prevalence according to different degrees of experience. METHODS: Observational, descriptive, cross-sectional study. Images of 108 adnexal masses were studied. The gold standard test was the definitive histopathological report. The diagnostic performance of 4 examiners with the following experience in ultrasound diagnosis of adnexal pathology: A > 20 years, B ≤ 20 to > 10 years, C ≤ 10 to > 5 years and D ≤ 5 years was compared, analyzing only images and blinded of clinical data of the patients, to issue a specific diagnosis with free writing. RESULTS: Prevalence of malignant masses 17.2% (15/87). The level of confidence in the examiners was considered according to the lack of diagnostic response: high (<6%) with experience of more than 10 years and moderate to low ≤ 10 years. The examiners with more than 5 years always showed likelihood ratio positive greater than 10, diagnostic accuracy greater than 90% and diagnostic Odds ratio greater than 46, not so for the examiner with less experience time who presented results with little clinical utility. The change in specific probability from pre-test to post-test improved consistently with years of experience. CONCLUSION: More than 10 years of experience with special dedication to advanced gynecological ultrasound are probably needed for a desired specific diagnostic performance coupled with high confidence in adnexal mass ultrasound.


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Ultrassom/educação , Doenças dos Anexos/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Radiologia/educação , Fatores de Tempo , Estudos Transversais , Probabilidade , Doenças dos Anexos/patologia , Competência Clínica , Curva de Aprendizado
2.
Rev. argent. dermatol ; 101(3): 131-140, set. 2020. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1288185

RESUMO

RESUMEN La histoplasmosis es una micosis profunda causada por el hongo dimorfo Histoplasma capsulatum (H. capsulatum). Ingresa al organismo principalmente por la vía inhalatoria en forma de microconidias, las cuales se transforman en elementos levaduriformes intracelulares, y luego se diseminan por vía hemática. La primoinfección en pacientes inmunocompetentes suele ser asintomática y de resolución espontánea, pero los pacientes inmunodeprimidos generalmente pueden presentar una enfermedad diseminada con compromiso mucocutáneo con pápulas, nódulos, gomas, úlceras de fondo granulomatoso serosanguinolento y costras. Se presenta un caso clínico de un paciente diabético inmunodeprimido con infección por H. capsulatum, en el cual se realiza diagnóstico a partir de las lesiones cutáneas.


SUMMARY Histoplasmosis is a deep mycosis caused by the dimorfo fungus Histoplasma capsulatum (H. capsulatum). Which enters the body mainly through the inhalation route in the form of microconidia which are transformed into intracellular levaduriform elements, and then disseminated by blood. The primary infection in immunocompetent patients is usually asymptomatic and spontaneously resolved, but immunocompromised patients can usually present with a disseminated disease with mucocutaneous involvement, with papules, nodules, gums, granulomatous serosanguinolent fundus ulcers and scabs. A clinical case of an immunocompromised diabetic patient with H. capsulatum infection is presented, in which diagnosis is made from the skin lesions.

3.
Big Data ; 8(4): 308-322, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32716641

RESUMO

This study proposes a novel bioinspired metaheuristic simulating how the coronavirus spreads and infects healthy people. From a primary infected individual (patient zero), the coronavirus rapidly infects new victims, creating large populations of infected people who will either die or spread infection. Relevant terms such as reinfection probability, super-spreading rate, social distancing measures, or traveling rate are introduced into the model to simulate the coronavirus activity as accurately as possible. The infected population initially grows exponentially over time, but taking into consideration social isolation measures, the mortality rate, and number of recoveries, the infected population gradually decreases. The coronavirus optimization algorithm has two major advantages when compared with other similar strategies. First, the input parameters are already set according to the disease statistics, preventing researchers from initializing them with arbitrary values. Second, the approach has the ability to end after several iterations, without setting this value either. Furthermore, a parallel multivirus version is proposed, where several coronavirus strains evolve over time and explore wider search space areas in less iterations. Finally, the metaheuristic has been combined with deep learning models, to find optimal hyperparameters during the training phase. As application case, the problem of electricity load time series forecasting has been addressed, showing quite remarkable performance.


Assuntos
Algoritmos , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Heurística , Modelos Teóricos , Pneumonia Viral/transmissão , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças , Humanos , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Probabilidade , Quarentena , SARS-CoV-2
4.
Rev. argent. dermatol ; 101(2): 61-70, jun. 2020. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1125823

RESUMO

RESUMEN Introducción: El carcinoma basocelular (CBC) es el cáncer humano más común. Es una neoplasia epitelial de malignidad limitada por un crecimiento lento y excepcional capacidad para dar metástasis a distancia. Es más frecuente en varones y en mayores de 40 años, foto tipos cutáneos I y II, una exposición solar intensa y prolongada, inmunosupresión y exposición a radiaciones ionizantes, ocurren de forma esporádica, aunque pueden ser hereditarios. Objetivo: Presentar un caso infrecuente de carcinoma basocelular en áreas no expuestas Presentación del caso: Paciente de 36 años, masculino, foto tipo III, sin antecedentes patológicos, medicamentosos, alérgicos y hereditarios; comerciante, sin antecedentes de exposición solar; consulta por lesión eritematosa en región antero-proximal del brazo derecho. Se observan otras dos lesiones, una en región pectoral derecha y otra en fosa ilíaca derecha; diagnóstico presuntivo CBC. Diagnóstico: Lesión 1: CBC. Lesión 2 y 3: CBC superficial. se solicita escisión quirúrgica convencional con ampliación de márgenes, la biopsia informa márgenes libres, se indican medidas de seguimiento y prevención. Conclusiones: se presenta un caso de CBC múltiples en áreas no expuestas a la radiación solar. Resulta fundamental el control y seguimiento de este paciente, pues tiene un alto riesgo de desarrollar melanoma.


ABSTRACT Introduction: Basal cell carcinoma (BCC) is the most common human cancer. It is an epithelial neoplasm of malignancy limited by slow growth and exceptional ability to metastasize at a distance. It is more frequent in men and in> 40 years, cutaneous phototypes I and II, a prolonged and intense solar exposure, immunosuppression and exposure to ionizing radiation, occur sporadically, although they can be hereditary. Objective: To present an infrequent case of basal cell carcinoma in unexposed areas Case presentation: Patient 36 years old, male, phototype III, without pathological, medicated, allergic and hereditary antecedents; merchant, not photo-exposed; consultation due to an erythematous lesion in the antero-proximal region of the right arm. Two other lesions are observed, one in the right pectoral region and the other in the right iliac fossa; presumptive diagnosis BCC. Diagnosis: Injury 1: BCC. Lesion 2 and 3: superficial BCC. conventional surgical excision with widening of margins is requested, biopsy reporting free margins, follow-up and prevention measures are indicated. Conclusions: a case with multiple CBC was presented in non-photoexposed areas without the clinic. Control and follow-up are essential given that they have a high risk of developing melanoma.

5.
Pediatr Transplant ; 20(6): 836-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27470315

RESUMO

West Nile Virus is an arbovirus that has rapidly spread throughout the United States since the first case was described in Queens, New York in 1999. There has been increasing reports of both community-acquired and organ-derived infections in renal transplant recipients. In immunocompromised individuals, WNV infection is a life-threatening disease with significant neurological morbidity. We report the only pediatric case of community-acquired WNV disease in a renal transplant recipient to undergo detailed long-term neuropsychological assessment. Increased surveillance and prompt treatment of WNV meningoencephalitis is critical, and our report highlights the effectiveness of immunosuppression reduction without compromising allograft outcomes.


Assuntos
Transplante de Rim , Meningoencefalite/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Febre do Nilo Ocidental/diagnóstico , Criança , Humanos , Hospedeiro Imunocomprometido , Masculino , Meningoencefalite/imunologia , Testes Neuropsicológicos , Complicações Pós-Operatórias/imunologia , Índice de Gravidade de Doença , Febre do Nilo Ocidental/imunologia
6.
Acta odontol. venez ; 52(2)2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-777792

RESUMO

Las lesiones híbridas son entidades poco frecuentes conformadas por elementos histopatológicos de distintas lesiones, la asociación de un Fibroma Osificante Central (FOC) con una Lesión Central de Células Gigantes (LCCG) es un ejemplo de ellas y representa el tipo más frecuentemente reportado en la literatura con diez casos hasta la fecha. A continuación presentamos el caso de una paciente de 24 años de edad, quien es referida al servicio de clínica estomatológica de la Facultad de Odontología, por presentar un aumento de volumen en la zona mandibular derecha que ocasiona asimetría facial, al examen intrabucal se observó una lesión tumoral de aproximadamente 2,5 cms. de diámetro y recubierta por mucosa bucal sana, que se extendía desde el canino inferior derecho hasta el segundo premolar del mismo lado (de 43 al 45). La paciente refiere una evolución de 3 meses y aparición posterior a un trauma. Se indican pruebas hematológicas y de vitalidad pulpar de los dientes involucrados, tomografía computarizada y biopsia Incisional, la cual concluye: LCCG asociada a FOC. Se trata con recesión quirúrgica total previo tratamiento endodóntico de los dientes involucrados y después de dos años la paciente se mantiene libre de recidiva. El reporte de este tipo de lesiones híbridas permitirá entender mejor en el futuro su comportamiento y a su vez brindar el tratamiento más adecuado a estos pacientes.


Hybrid lesions are rare entities formed by histopathological elements of different lesions, the association of a Central Ossifying Fibroma (COF) with a Central Giant Cell Lesion (CGCL) is an example of them and represents the most frequently reported type in the literature, only ten cases to date. We present the case of a 24 years female patient, who is referred to the dental clinic service to present a swelling in the right mandibular region causing facial asymmetry, the intra oral examination revealed a 2,5 cm lesion covered with healthy oral mucosa which extended from the distal aspect of lower right canine to the right second bicuspid, with 3 months evolution and associated to a trauma. Haematological tests, pulp vitality of involved teeth, CT scan and incisional biopsy were indicated, concluding a diagnosis of COF associated to CGCL. The decision was made to go for the surgical approach of the lesion with previous endodontic treatment of involved teeth and after two years the patient remains free of recurrence. The report of this type of hybrid lesions helps to understand their behavior and guides to the best treatment for these patients.


Assuntos
Humanos , Feminino , Adulto Jovem , Células Gigantes/patologia , Fibroma Ossificante/patologia , Granuloma de Células Gigantes/patologia , Fibroma Ossificante , Arcada Osseodentária , Procedimentos Cirúrgicos Bucais
7.
Rev. chil. obstet. ginecol ; 78(2): 129-133, 2013. tab
Artigo em Espanhol | LILACS | ID: lil-682342

RESUMO

Presentamos un caso de embarazo cornual o intersticial diagnosticado en forma precoz a través de ecografía transvaginal, tratado exitosamente, en forma conservadora, con dosis única sistémica de metotrexato.


We present a case of cornual or interstitial pregnancy diagnosed during early stage through transvaginal ultrasound, treated successfully with single systemic intramuscular methotrexate dose.


Assuntos
Humanos , Feminino , Gravidez , Adulto , Gravidez Ectópica/tratamento farmacológico , Metotrexato/administração & dosagem , Gravidez Ectópica , Metotrexato/uso terapêutico , Resultado do Tratamento
9.
Pediatr Nephrol ; 16(1): 82-4, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11198611

RESUMO

A 12-year-old African American male with homozygous sickle cell disease (SCD) was admitted with insidious onset of periorbital and scrotal edema. The initial evaluation failed to reveal any underlying monoclonal gammopathy, or cryoglobulinemia, or other systemic causes for the renal disease. A percutaneous renal biopsy was consistent with immunotactoid glomerulopathy (ITG), which is rare in children and is characterized histologically by fibrillar deposits in the glomeruli. Children can present with symptoms of nephrotic syndrome and progress to end stage renal disease. Our patient was treated with an ACE inhibitor and is currently free of edema and with normal renal function on follow-up at 1 year. Immunotactoid glomerulopathy should be considered in the differential diagnosis of nephrotic syndrome in children with sickle cell disease. Renal biopsy is indicated in children with sickle cell disease and nephrotic syndrome and ITG should be considered as potential cause. Although there is no effective treatment for this condition, ACE inhibitors can decrease the protein-uria and possibly delay the progression to end stage renal disease. The side effects related to the use of ACE inhibitors should be monitored. These include renal impairment, hyperkalemia, anemia, neutropenia, and angioedema. Since we have a short follow-up in our patient, the role and safety of ACE inhibitors in the management of ITG need further evaluation.


Assuntos
Anemia Falciforme/complicações , Nefropatias/complicações , Nefropatias/imunologia , Glomérulos Renais , Criança , Diagnóstico Diferencial , Humanos , Nefropatias/patologia , Glomérulos Renais/patologia , Masculino , Síndrome Nefrótica/etiologia
10.
Kidney Int ; 59(1): 238-45, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11135076

RESUMO

BACKGROUND: Epidemiological studies have suggested that low birthweight is a risk factor for the development of essential hypertension in adulthood, but the mechanism is unknown. METHODS: A rat model of intrauterine growth retardation was employed. Pregnant Sprague-Dawley rats were kept on 6% protein or on control isocaloric 20% protein diet from gestational day 12 until term. Systolic blood pressures of the offspring were monitored by the tail cuff method. Apoptosis was determined by the TUNEL method, cell proliferation by anti-Ki67 antibody, and the total number of glomeruli by the maceration method. Results are mean +/- SD. RESULTS: The kidney and body sizes of the offspring from the low-protein pregnancies (LP) were proportionately decreased at birth. Full catch-up growth occurred during the first two weeks of life. The kidneys were normal by standard histology but exhibited increased apoptosis without increased cell proliferation at eight weeks of age. The total number of glomeruli per kidney was decreased by 28% in males (P < 0.001) and by 29% in females (P < 0.01). By eight weeks of age, both male and female LP had systolic blood pressures that were 20 to 25 mm Hg higher than those of control animals (P < 0.001), and their 18-month survival was significantly decreased (44 vs. 93%, P < 0.01). During the prehypertensive stage, at four weeks of age, PRA in LP was low (1.7 +/- 1.4 vs. 19.7 +/- 5.5 ng/mL/hour in males, P < 0.0001; 4.9 +/- 2.2 vs. 14.9 +/- 7.2 ng/mL/hour in females, P < 0.0005), and aldosterone was high (93 +/- 15 vs. 54 +/- 27 pg/mL in males, P < 0. 005; 93 +/- 20 vs. 48 +/- 20 pg/mL in females, P < 0.0001). Smaller but significant differences persisted at eight weeks of age. CONCLUSIONS: Adult blood pressure profile is susceptible to prenatal programming by maternal low-protein diet in the rat. The mechanism may involve an altered renin-aldosterone axis and a deficit in total nephron number.


Assuntos
Proteínas Alimentares/administração & dosagem , Retardo do Crescimento Fetal/complicações , Hipertensão/etiologia , Prenhez/fisiologia , Envelhecimento/sangue , Envelhecimento/fisiologia , Aldosterona/sangue , Animais , Apoptose , Pressão Sanguínea , Creatina/sangue , Feminino , Rim/crescimento & desenvolvimento , Rim/fisiopatologia , Glomérulos Renais/patologia , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Valores de Referência , Renina/sangue , Análise de Sobrevida
11.
Clin Pediatr (Phila) ; 39(9): 529-33, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11005366

RESUMO

Nephrotoxicity, as evidenced by renal insufficiency is a well-known consequence of gentamicin therapy. We report two patients with gentamicin-induced syndrome of hypokalemic metabolic alkalosis and hypomagnesemia. Both had complete recovery of renal tubular function after cessation of antibiotic therapy. These cases emphasize the need to routinely monitor patients receiving gentamicin therapy for electrolyte abnormalities to avoid potential morbidity.


Assuntos
Alcalose/induzido quimicamente , Antibacterianos/efeitos adversos , Gentamicinas/efeitos adversos , Hipopotassemia/induzido quimicamente , Deficiência de Magnésio/induzido quimicamente , Injúria Renal Aguda/induzido quimicamente , Adulto , Antibacterianos/administração & dosagem , Infecção Hospitalar/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Gentamicinas/administração & dosagem , Humanos , Lactente , Injeções Intravenosas , Masculino , Resistência a Meticilina , Síndrome , Resultado do Tratamento
12.
Clin Exp Hypertens ; 22(3): 289-301, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10803734

RESUMO

The mechanism(s) by which dopamine inhibits Na+-K+-ATPase activity in the renal proximal tubule is still controversial. We studied the short-term effects of dopamine on the sodium pump in rat renal proximal tubule suspensions with the 86Rb uptake method. Dopamine and the D1-like agonist, SKF81297, initially stimulated Na+-K+-ATPase activity at 5 min and subsequently inhibited it at 10 min and 20 min; the inhibition by 10 microM dopamine at 20 min was 21.3 +/- 4.5%. The inhibitory effect of dopamine on Na+-K+-ATPase activity was mimicked by thymeleatoxin (a classical protein kinase C [PKC] agonist) while Sp-8-CPT-cAMPS (a protein kinase A [PKA] agonist) had no effect. However, the combination of the PKC and PKA agonists mimicked the biphasic effects of dopamine and SKF81297. Rp-8-CPT-cAMPS (a PKA inhibitor), U-73122 (a phospholipase C inhibitor), or calphostin C (a PKC inhibitor), blocked the dopamine-mediated biphasic effects on Na+-K+-ATPase activity. It is suggested that the biphasic effects of dopamine on Na+-K+-ATPase activity (an initial stimulation and a subsequent inhibition) are transduced by activating both PKA and PKC through a D1-like receptor.


Assuntos
Cardiotônicos/farmacologia , Dopamina/farmacologia , Túbulos Renais Proximais/metabolismo , Radioisótopos de Rubídio/farmacocinética , Animais , Benzazepinas/farmacologia , Colagenases/farmacologia , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Agonistas de Dopamina/farmacologia , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Transporte de Íons/efeitos dos fármacos , Túbulos Renais Proximais/diagnóstico por imagem , Túbulos Renais Proximais/efeitos dos fármacos , Masculino , Ésteres de Forbol/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Proteína Quinase C/efeitos dos fármacos , Proteína Quinase C/metabolismo , Pirrolidinonas/farmacologia , Cintilografia , Ratos , Ratos Endogâmicos WKY , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Tionucleotídeos/farmacologia , Fosfolipases Tipo C/antagonistas & inibidores
13.
Pediatr Nephrol ; 13(4): 298-300, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10454777

RESUMO

When focal segmental glomerulosclerosis (FSGS) has reached the stage of chronic renal insufficiency, further progression is usually considered inevitable. African-American patients are believed to exhibit a particularly aggressive form of FSGS. We have treated five African-American patients, aged 11-18 years, with FSGS and reduced renal function using intensive intravenous methylprednisolone protocol, combined with chlorambucil in three cases. All patients had a pretreatment creatinine clearance of less than 50 ml/min per 1.73 m2. Three patients responded with normalization of creatinine clearance and serum albumin levels and had no or only minimal proteinuria at latest follow-up. One patient showed no improvement and one patient progressed to end-stage renal disease. These findings indicate, for the first time, that even severe FSGS may respond to aggressive methylprednisolone with or without alkylating agent treatment, and that African-American race does not preclude a favorable response.


Assuntos
Anti-Inflamatórios/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Clorambucila/administração & dosagem , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Metilprednisolona/administração & dosagem , Adolescente , População Negra , Criança , Pré-Escolar , Quimioterapia Combinada , Feminino , Glomerulosclerose Segmentar e Focal/fisiopatologia , Humanos , Injeções Intravenosas , Masculino
14.
Ann Trop Paediatr ; 19(3): 297-300, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10715718

RESUMO

This case report describes nephrotic syndrome in a 7-year-old boy coincident with Toxocara canis infection. This rare association was confirmed by elevated Toxocara-specific IgM titres. Treatment with corticosteroids resulted in remission of renal symptoms as well as abatement of the T. canis infection. The relationship between T. canis infection and glomerular disease is still unclear; nephrotic syndrome may be another manifestation of T. canis infection.


Assuntos
Síndrome Nefrótica/complicações , Toxocara canis , Toxocaríase/complicações , Animais , Anticorpos Anti-Helmínticos/sangue , Criança , Glucocorticoides/uso terapêutico , Humanos , Masculino , Síndrome Nefrótica/tratamento farmacológico , Prednisolona/uso terapêutico , Toxocara canis/imunologia , Toxocaríase/tratamento farmacológico
15.
Am J Physiol ; 274(6): C1661-6, 1998 06.
Artigo em Inglês | MEDLINE | ID: mdl-9611132

RESUMO

To assess the role of distal nephron apical Na channel (ENaC) gene expression in Na wasting by the immature kidney, ENaC alpha-, beta-, and gamma-subunit mRNA levels were examined in the rat by RT-PCR. In microdissected nephron segments, all three ENaC subunit mRNAs were detected in the distal convoluted tubule, connecting tubule, cortical collecting duct, and outer medullary collecting duct. The inner medullary collecting duct and all other nephron segments were consistently negative. The mRNA levels were quantified in kidneys at different developmental stages by multiplex RT-PCR with "primer dropping," with endoplasmic reticulum-specific cyclophilin mRNA as an internal standard. All three ENaC mRNA levels were low or undetectable on gestational day 16 and only slightly higher 3 days before birth. A sharp rise was observed between 3 days before and 1-3 days after birth; the levels at postnatal days 1-3 were already similar to those of adult kidneys. The results suggest that ENaC subunit gene expression is not a limiting factor in the full-term newborn rat kidney, but low levels of expression may limit distal Na absorption in more immature kidneys, such as those of very premature human infants.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Rim/crescimento & desenvolvimento , RNA Mensageiro/metabolismo , Canais de Sódio/genética , Animais , Animais Recém-Nascidos , Rim/embriologia , Rim/metabolismo , Reação em Cadeia da Polimerase , DNA Polimerase Dirigida por RNA , Ratos , Ratos Sprague-Dawley
16.
Am J Physiol ; 268(2 Pt 2): F279-84, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7864167

RESUMO

In the brain, dopamine, via protein kinase A (PKA) activation of dopamine- and cAMP-regulated phosphoprotein (DARPP-32), inhibits protein phosphatase 1 (PP1) activity and keeps Na(+)-K(+)-adenosinetriphosphatase (ATPase) in its phosphorylated inactive state. In the present study, we examined the relationship among dopamine, PP1, and Na(+)-K(+)-ATPase activities in renal proximal tubules. PP1 activity in proximal tubules was not decreased by dopamine (5 x 10(-9)-10(-4) M), fenoldopam (5 x 10(-6) M), or norepinephrine (5 x 10(-7) M). In contrast, in the medullary thick ascending limb of Henle and in the brain striatum, PP1 activity was decreased by fenoldopam (5 x 10(-6) M). We also showed that the ability of dopamine (10(-6) M) to inhibit Na(+)-K(+)-ATPase activity in proximal tubules (assessed by ouabain-sensitive 86Rb uptake) occurred in the absence or presence of a sodium clamp with 5 microM monensin. Thus the inhibitory effect of dopamine on Na(+)-K(+)-ATPase activity in proximal tubules is not regulated by PP1 activity. Tautomycin and okadaic acid by themselves, at concentrations that inhibited PP1 activity, had no effect on Na(+)-K(+)-ATPase activity in proximal tubules. The ability of a dopamine D1 agonist, fenoldopam, to inhibit PP1 activity in brain striatum and in medullary thick ascending limb, but not in proximal tubules, suggests differential organ and nephron segment regulation of PP activity.


Assuntos
Dopamina/farmacologia , Túbulos Renais Proximais/enzimologia , Fosfoproteínas Fosfatases/metabolismo , Animais , Corpo Estriado/enzimologia , Fenoldopam/farmacologia , Medula Renal , Alça do Néfron/enzimologia , Masculino , Monensin/farmacologia , Norepinefrina/farmacologia , Ouabaína/farmacologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Proteína Fosfatase 1 , Ratos , Ratos Endogâmicos WKY , Rubídio/farmacocinética , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismo
17.
Clin Perinatol ; 19(1): 69-84, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1576775

RESUMO

Renal function can now be evaluated in utero and after birth. Most of the methods used to investigate suspected renal dysfunction or disease are not presently applicable to the fetus; however, prenatal and postnatal evaluation of renal function has assumed a greater importance as the consequences of birth before term become more apparent.


Assuntos
Doenças Fetais/diagnóstico , Nefropatias/diagnóstico , Testes de Função Renal/normas , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/urina , Taxa de Filtração Glomerular , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Recém-Nascido Prematuro , Nefropatias/diagnóstico por imagem , Nefropatias/urina , Testes de Função Renal/métodos , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/normas , Ultrassonografia , Urinálise
18.
J Cell Physiol ; 104(3): 403-13, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7419611

RESUMO

Hybrids between a tumorigenic Chinese hamster cell line (DC3F-aza) and normal mouse thymus cells very rapidly lost most of their mouse chromosomes, whereas hybrids between tumorigenic mouse cell lines (either Cl.1D of L cell line origin, or PCC4-aza 1 teratocarcinoma cells) and normal Chinese hamster thymus cells lost most of their hamster chromosomes. From three such fusion experiments, 20 cell lines were developed which all followed the same evolution, namely, the elimination of the majority of the chromosomes contributed by the normal thymus cell. In some hybrids, the elimination process resulted in the total absence of intact chromosomes contributed by the thymus cell parent. Such hybrids were distinguished from revertant parental cells growing in the selective medium by the presence of at least one enzyme in their cell extracts which displayed the electrophoretic mobility of the enzyme of the thymus cell parent. These observations, together with data from other reports, suggest that, as a rule, interspecific cell hybrids which develop upon fusion between normal diploid cells and tumorigenic cell lines maintain the chromosomes of the latter and eliminate preferentially many or most of the chromosomes contributed by the normal cell parents, independent of the respective species of the parental cells.


Assuntos
Deleção Cromossômica , Células Híbridas/citologia , Animais , Fusão Celular , Linhagem Celular , Cricetinae , Cricetulus , Citogenética , Cariotipagem , Camundongos , Neoplasias Experimentais , Timo/citologia
19.
Somatic Cell Genet ; 6(3): 419-33, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-7404272

RESUMO

Hybrids between PCC4-aza 1 teratocarcinoma cells and either thymus cells (PcT and RPcT hybrids) or Lc lymphocytic leukemia cells (PcLc hybrids) are carcinoma cells and when injected into hosts they produce tumors which are teratocarcinomas. PcT and RPcT hybrids) or Lc lymphocytic leukemia cells (PcLc hybrids) are carcinoma cells and when injected into hosts they produce tumors which are teratocarcinomas. PcT and RPcT hybrid tumors are well differentiated and include a large variety of somatic tissues. In most PcLc tumors, neuroectoderm differentiation is predomonant. Like the PCC4 parental cells, PcT, RPcT, and PcLc hybrids carry F9 embryonic antigens and do not express perceptible amounts of H-2 alloantigens. Nonexpression of the H-2d haplotype of the thymus cell parent in PcT hybrids is not due to the loss of chromosome 17 which carried the major histocompatibility complex.


Assuntos
Antígenos de Superfície/análise , Células Híbridas/citologia , Linfócitos/imunologia , Teratoma/imunologia , Animais , Antígenos de Neoplasias/análise , Diferenciação Celular , Antígenos H-2/análise , Células Híbridas/imunologia , Linfócitos/citologia , Camundongos , Neoplasias Experimentais/imunologia , Fenótipo , Teratoma/patologia
20.
Somatic Cell Genet ; 6(2): 171-86, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6967231

RESUMO

Hybrids formed in vivo between Cl.1D tumor cells and host cells have been shown to carry a copy of each chromosome pair contributed by the host cell parent (1). However, in these hybrids, the tissue type of the host cell parents remained unknown. In the present study, hybrids between the malignant Cl.1D fibroblasts and either normal diploid fibroblasts (CF hybrids) or normal thymocytes (CT hybrids) were examined. These hybrids produced tumors when injected into host mice. Metaphases of growing hybrid cell tumors were analyzed. Neither CF nor CT malignant hybrids showed loss of any specific chromosome pair contributed by the normal cell parent. Since elimination of any chromosome pair contributed by the diploid fibroblast parent is not a prerequisite for CF hybrid tumoral growth, it seems unlikely that malignancy of hybrids results from nonexpression of normal alleles of those genes putatively implied in malignancy of Cl.1D cells.


Assuntos
Cromossomos , Células Híbridas , Neoplasias Experimentais/genética , Aneuploidia , Animais , Bandeamento Cromossômico , Fibroblastos , Fibrossarcoma/genética , Cariotipagem , Células L , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos DBA , Neoplasias Experimentais/etiologia , Linfócitos T/ultraestrutura
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