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1.
Vet Pathol ; 50(2): 274-80, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22895538

RESUMEN

ß-Catenin, encoded by the ctnnb1 gene, plays a critical role in intercellular adhesion, and its altered expression has been implicated in tumor progression in humans and animals. The aims of this study were to examine the alterations in ß-catenin expression in canine melanoma as well as the causes of these changes (eg, E-cadherin or exon 3 mutations) and to compare identified changes between skin and oral melanomas. Forty-two primary canine skin and oral melanoma tissue samples were used in the study. The expression levels of ctnnb1 and the levels of E-cadherin/ß-catenin complex in the tissues were determined by semiquantitative RT-PCR and immunohistochemistry, respectively. The mutational status of ß-catenin exon 3 was examined by DNA sequencing. RT-PCR revealed higher levels of ctnnb1 expression in oral melanoma tissues compared with normal melanocytes, irrespective of sex or histopathological appearance of the tissue (ie, amelanotic vs melanotic). Immunohistochemistry revealed simultaneous loss of membrane E-cadherin/ß-catenin complex and cytoplasmic accumulation of both proteins in 37 cases (84%). Intranuclear ß-catenin was also detected in all tissues with reduced membrane ß-catenin expression. In mutational analyses, one amelanotic oral melanoma showed 13 single nucleotide polymorphisms (SNPs); however, after protein translation, all the SNPs were silent mutations. The present study demonstrates that dysregulation of E-cadherin/ß-catenin complexes is involved in both types of canine melanotic tumors and that the disruption of E-cadherin/ß-catenin complexes and increased ß-catenin may induce tumor progression and malignancy.


Asunto(s)
Cadherinas/metabolismo , Enfermedades de los Perros/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Melanoma/veterinaria , Neoplasias de la Boca/veterinaria , Neoplasias Cutáneas/veterinaria , beta Catenina/metabolismo , Animales , Análisis Mutacional de ADN/veterinaria , Perros , Inmunohistoquímica/veterinaria , Melanoma/metabolismo , Neoplasias de la Boca/metabolismo , Polimorfismo de Nucleótido Simple/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Neoplasias Cutáneas/metabolismo , Estadísticas no Paramétricas , beta Catenina/genética
2.
Rhinology ; 51(3): 280-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23943738

RESUMEN

BACKGROUND: Isolated sphenoid sinus disease (ISSD) is rare. Fungus ball (FB) is the third most common ISSD. We analysed the characteristics of isolated sphenoid FB based on demographic data, presenting symptoms, preoperative computed tomography (CT), magnetic resonance imaging (MRI), and treatment outcomes. METHODOLOGY: From 1999 to 2012, 29 patients were identified with isolated sphenoid FB. Demographic data; clinical characteristics; endoscopic, CT, and MRI findings and treatment outcomes were retrospectively analysed. RESULTS: The most common symptom was headaches, which were localized in various regions of the brain. Other symptoms were uncommon. The most common CT findings were sclerosis, calcification, enlarged sinus and total opacification. On T2-weighted MRI images, we most commonly observed signal void. Endoscopic transnasal paraseptal sphenoidotomy was performed in all patients, and for most, this was performed under local anaesthesia. No recurrence was observed in any patient. CONCLUSION: Isolated sphenoid FB is predominantly observed in older women, and it is characterised by headaches and sclerosis of the sinus wall observed on CT scans. In cases of isolated sphenoid FB, endoscopic transnasal paraseptal sphenoidotomy can be successfully performed under local anaesthesia, which may facilitate rapid recovery and a low morbidity rate.


Asunto(s)
Micosis/diagnóstico , Micosis/cirugía , Seno Esfenoidal/microbiología , Sinusitis del Esfenoides/diagnóstico , Sinusitis del Esfenoides/cirugía , Adulto , Anciano , Endoscopía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Micosis/microbiología , Estudios Retrospectivos , Sinusitis del Esfenoides/microbiología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
3.
Vet Pathol ; 47(2): 285-91, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20139375

RESUMEN

The Wnt/beta-catenin signal transduction pathway is important in many developmental processes and during tumorigenesis. beta-Catenin acts as a signal transducer. To investigate whether the Wnt/beta-catenin signal transduction pathway is involved in canine cutaneous melanomagenesis, 18 formalin-fixed paraffin-embedded canine cutaneous melanotic tumor tissues were examined. For cloning and sequencing of the full-length canine ctnnb1 gene encoding beta-catenin, conserved sequences of the human and mouse ctnnb1 gene were used to design the primers. For analysis of expression and translocation of beta-catenin in canine cutaneous melanotic tumors, semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry were performed. The canine ctnnb1 sequence showed a high degree of similarity to those of human and mouse. Semiquantitative RT-PCR showed a substantial increase in expression of ctnnb1 mRNA in canine cutaneous melanotic tumors compared to normal canine melanocytes, regardless of whether the tumor was benign or malignant. Immunohistochemistry revealed cytoplasmic accumulation of beta-catenin in melanotic tumors. In melanoma tissues, nuclear translocation of beta-catenin was also observed. The present study demonstrated that abnormal intracellular accumulation and substantially increased expression of beta-catenin are involved in canine cutaneous melanotic tumor.


Asunto(s)
Enfermedades de los Perros/patología , Melanoma/veterinaria , Neoplasias Cutáneas/veterinaria , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Secuencia de Aminoácidos , Animales , Enfermedades de los Perros/genética , Enfermedades de los Perros/metabolismo , Perros , Femenino , Regulación Neoplásica de la Expresión Génica , Inmunohistoquímica/veterinaria , Masculino , Melanoma/metabolismo , Melanoma/patología , Datos de Secuencia Molecular , ARN Neoplásico/química , ARN Neoplásico/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Alineación de Secuencia , Análisis de Secuencia de ADN , Transducción de Señal , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Estadísticas no Paramétricas , beta Catenina/genética
4.
J Small Anim Pract ; 48(10): 579-83, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17490446

RESUMEN

This case report describes the diagnosis of secondary malignant lymphoedema in two dogs that had undergone a mastectomy. A remarkable severe oedematous lesion associated with lameness in the right hindlimb was observed in both cases. Diagnostic imaging examinations, including direct pedal lymphangiography (case 1) and lymphoscintigraphy (case 2), showed obstruction of lymph flow in the lymphatics of the right hindlimbs. Although the recommended medical management and physiotherapy had been applied to resolve the problems, oedema did not improve in the damaged region in both cases. Results of histopathological examinations suggested that the cause of the obstructed lymph flow was neoplastic cells in the lymphatics of the right hindlimb in both dogs.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Linfedema/veterinaria , Mastectomía/veterinaria , Complicaciones Posoperatorias/veterinaria , Animales , Carcinoma/secundario , Carcinoma/cirugía , Carcinoma/veterinaria , Diagnóstico Diferencial , Enfermedades de los Perros/sangre , Enfermedades de los Perros/fisiopatología , Perros , Femenino , Miembro Posterior , Cojera Animal/etiología , Linfedema/complicaciones , Linfedema/diagnóstico , Neoplasias Mamarias Animales/patología , Neoplasias Mamarias Animales/cirugía , Metástasis de la Neoplasia , Complicaciones Posoperatorias/diagnóstico
5.
Lung Cancer ; 30(3): 187-92, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11137203

RESUMEN

STUDY OBJECTIVES: Cell lysis and tumor necrosis release cytokeratin, a tumor marker of lung cancer, into the serum. The serum cytokeratin level can also be elevated in benign cavitary lung diseases. The purpose of this study was to evaluate whether Cyfra 21-1 can differentiate malignant lung diseases from benign diseases with cavitary lesions. DESIGN: This study is a retrospective review of the case records of patients with lung lesions seen during a 4-year period from January 1993 to May 1996. SETTING AND PATIENTS: Serum Cyfra 21-1 levels were measured in 306 patients with lung cancer (n = 143) or benign lung disease (n = 163). The patients were grouped according to radiologic evidence of cavitary lung lesions. Lung cancer included both non-small cell (n = 123) and small cell (n = 20) lung cancers, and the benign diseases include tuberculosis (n = 87), abscess (n = 26), pneumonia (n = 4), and others (n = 46). MEASUREMENTS AND RESULTS: Although Cyfra 21-1 clearly differentiated cavitary lung cancer (15.0, 9.1-29.8 ng/ml, median and interquartile range, n = 39) from benign cavitary disease (P < 0.001), and noncavitary lung cancer from benign noncavitary disease (1.7, 0.9-2.6 ng/ml, n = 108, P < 0.001), it could not differentiate noncavitary lung cancer (5.0, 2.1-12.4 ng/ml, n = 104) from benign cavitary diseases (3.3, 1.4-8.3 ng/ml, n = 55, P = 0.45). CONCLUSIONS: Serum Cyfra 21-1 is a useful tumor marker for differentiating benign from malignant lung diseases. However, different cutoff values are needed, depending on the presence of cavitary lesions. We recommend cutoff values of 30 ng/ml for cavitary lung diseases and 6 ng/ml for noncavitary lung diseases. If there are no radiologic data, a cutoff value of 15 ng/ml is recommended.


Asunto(s)
Antígenos de Neoplasias/análisis , Biomarcadores de Tumor/análisis , Enfermedades Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Queratina-19 , Queratinas , Masculino , Persona de Mediana Edad , Valores de Referencia , Estudios Retrospectivos , Sensibilidad y Especificidad
6.
Cancer Biother Radiopharm ; 15(4): 381-6, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11041023

RESUMEN

Neuron-specific enolase (NSE) and lactate dehydrogenase (LDH) are tumor markers of small cell lung cancer (SCLC) which were reported to predict outcome of patients with SCLC. We previously reported that dipyridamole-modulated Tc-99m sestamibi (dipyridamole-MIBI) single photon emission computed tomography (SPECT) could predict the response to chemotherapy in SCLC patients. The purpose of this study was to compare dipyridamole-MIBI and pretreatment serum levels of NSE and LDH for the prediction of response to chemotherapy in SCLC. Twenty-eight SCLC patients underwent dipyridamole-MIBI SPECT 3 to 7 days before starting chemotherapy (80 mg/m2 etoposide and 80 mg/m2 cisplatin every 3 or 4 weeks for at lease two cycles). Serum levels of NSE and LDH were also measured at the same day of the imaging. Tomographic images before and after 0.84 mg/kg dipyridamole infusion were acquired 1 hour after injection of 370 (10 mCi) and 1,110 (30 mCi) MBq MIBI, respectively. The response to chemotherapy was grouped as specified as complete (CR), partial response (PR), no change (NC), and progressive disease (PD), according to the change in tumor size on chest roentgenography and CT. Patients showing CR and PR were classified as responders, and those who showed NC and PD were considered nonresponders. Among the 28 patients, 15 were responders (2 CR, 13 PR) and 13 were nonresponders (11 NC, 2 PD). The change of tumor-to-normal lung ratio (T:NL) after infusion of dipyridamole was significantly higher in responders as compared with nonresponders (0.38 +/- 0.64 vs. -0.38 +/- 0.50, respectively, p = 0.002). However, pretreatment serum NSE and LDH levels did not correlate with the response to chemotherapy. Increase of T:NL after dipyridamole infusion was a strong negative predictor of chemotherapeutic response in SCLC patients, while NSE and LDH could not predict it.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma de Células Pequeñas/sangre , Carcinoma de Células Pequeñas/diagnóstico por imagen , L-Lactato Deshidrogenasa/sangre , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/diagnóstico por imagen , Fosfopiruvato Hidratasa/sangre , Tecnecio Tc 99m Sestamibi , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Pequeñas/tratamiento farmacológico , Dipiridamol/administración & dosificación , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas
7.
J Vet Med Sci ; 63(3): 269-74, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11307926

RESUMEN

To examine in vivo effects of egg white derivatives (EWD), the numbers of peripheral blood cells and neutrophil phagocytosis were evaluated in cats injected intramuscularly with cyclophosphamide (CPA). There were no changes in the number of red blood cells (RBC) or packed cell volume (PCV) values regardless of oral administration of EWD or injection of CPA, but the numbers of platelets, white blood cells (WBC) and neutrophils in cats administered EWD significantly increased (p<0.05 to 0.01) when compared with those in control cats which received saline solution. In addition, the administration of EWD resulted in a significant enhancement in the phagocytic activity of neutrophils (p<0.01) when compared to control cats, suggesting that EWD has a stimulating effect on leukocyte progenitors. The numbers of platelets, WBC and neutrophils, and the phagocytic activity of neutrophils in cats injected with CPA alone were significantly lower (p<0.05 to 0.01) than those in control cats. However, co-administration of EWD to cats injected with CPA resulted in a significant increase in the numbers of platelets, WBC and neutrophils (p<0.05 to 0.01), and in the phagocytic response of neutrophils (p<0.01) when compared to cats injected with CPA alone. Therefore, these results suggest that co-administration of EWD may be effective in reducing some possible side effects in animals treated with immunosuppressive or antitumor agents.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Ciclofosfamida/efectos adversos , Proteínas del Huevo/inmunología , Inmunosupresores/efectos adversos , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Animales , Plaquetas/citología , Plaquetas/efectos de los fármacos , Gatos , Proteínas del Huevo/farmacología , Recuento de Eritrocitos/veterinaria , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Femenino , Hematócrito/veterinaria , Huésped Inmunocomprometido/efectos de los fármacos , Huésped Inmunocomprometido/inmunología , Recuento de Leucocitos/veterinaria , Masculino , Fagocitosis/efectos de los fármacos , Fagocitosis/inmunología , Recuento de Plaquetas/veterinaria
8.
Meat Sci ; 45(3): 405-10, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22061477

RESUMEN

This research was conducted to find restriction fragment length polymorphism (RFLP) markers related to growth performance and meat quality of Korean Native Cattle. DNA was extracted from the blood of Korean Native Cattle steers and Southern blot analysis of genomic DNA digested with restriction enzymes was performed using a bovine growth hormone (GH) cDNA probe. The restriction enzyme that detected RFLPs most frequently was TaqI. Digested fragments with TaqI revealed 6.15, 5.2, 4.5, 4.3, 2.6, 2.4, 1.6, 0.5, 0.3 and 0.2 kb bands. The most frequent band was 1.6 kb, which was exhibited in 11 out of 15 animals. In GH-TaqI RFLP, the 4.3 kb band was correlated with average daily gain (p = 0.021) and carcass weight (p = 0.035). No markers related to meat quality were found.

9.
J Vet Intern Med ; 28(2): 429-36, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24372863

RESUMEN

BACKGROUND: An excess of intra-abdominal fat is observed frequently in dogs with hyperadrenocorticism (HAC). Adipokine dysregulation is a possible cause of complications related to visceral obesity, but little information is available on adipokine in dogs with naturally occurring HAC. OBJECTIVES: To examine the differences in the circulating adipokines concentrations in overweight dogs with and without pituitary-dependent HAC (PDH). ANIMALS: Thirty healthy dogs and 15 client-owned dogs with PDH. METHODS: Case-controlled observational study, which enrolled 15 overweight dogs diagnosed with PDH and 30 otherwise healthy dogs of similar body condition score. Nine of 15 dogs with PDH were treated with low-dose trilostane twice daily and reassessed after treatment. RESULTS: The serum leptin (P < .0001) and insulin (P < .0001) concentrations were significantly higher in the PDH group (leptin, 22.8 ± 8.8 [mean ± SD]; insulin, 9.1 ± 6.1) than the healthy group (leptin, 4.9 ± 3.7; insulin, 1.9 ± 0.9). However, there were no significant differences in the adiponectin, resistin, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-10, and IL-18 levels between the 2 groups. In the PDH group, the serum cortisol concentrations had a linear association with the leptin concentrations, and there were significant decreases in the leptin (P = .0039) and insulin (P = .0039) levels after trilostane treatment. However, the leptin and insulin levels remained higher after trilostane treatment than in healthy control dogs with similar body condition score. CONCLUSIONS AND CLINICAL IMPORTANCE: Hypercortisolemia in dogs with PDH might upregulate the circulating leptin levels. However, a large population-based study will be necessary to determine whether the upregulation of leptin is involved directly with the complications caused by HAC.


Asunto(s)
Adipoquinas/sangre , Hiperfunción de las Glándulas Suprarrenales/veterinaria , Enfermedades de los Perros/sangre , Adipoquinas/fisiología , Hiperfunción de las Glándulas Suprarrenales/sangre , Hiperfunción de las Glándulas Suprarrenales/tratamiento farmacológico , Hiperfunción de las Glándulas Suprarrenales/fisiopatología , Animales , Estudios de Casos y Controles , Dihidrotestosterona/análogos & derivados , Dihidrotestosterona/farmacología , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/fisiopatología , Perros/sangre , Perros/fisiología , Inhibidores Enzimáticos/uso terapéutico , Femenino , Hidrocortisona/sangre , Hidrocortisona/fisiología , Insulina/sangre , Insulina/fisiología , Leptina/sangre , Leptina/fisiología , Masculino
10.
J Vet Intern Med ; 27(1): 91-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23167780

RESUMEN

BACKGROUND: Trilostane is commonly used to treat pituitary-dependent hyperadrenocorticism (PDH) in dogs. There are differing opinions regarding the dose and frequency of trilostane administration in dogs with PDH. OBJECTIVES: To compare the efficacy of 2 trilostane protocols in the treatment of dogs with PDH. ANIMALS: Sixteen client-owned dogs with PDH and a body weight <5 kg. METHODS: Prospective observational study. Group A (n=9; low-dose treatment group) received 0.78 ± 0.26 mg of trilostane/kg PO every 12 h and group B (n = 7; high-dose treatment group) 30 mg of trilostane/dog PO every 24 h. All of the dogs were reassessed at 2, 4, 8, 12, 16, and 24 weeks after the initiation of treatment. RESULTS: An improvement in both ACTH-stimulated serum cortisol concentrations and clinical signs occurred more slowly in group A than in group B; however, after 20 weeks of treatment, 2/7 dog in group B had clinical signs and abnormal laboratory findings consistent with hypoadrenocorticism. At 24 weeks, an improvement in the clinical findings of all of the dogs in both groups was detected. CONCLUSIONS AND CLINICAL IMPORTANCE: In dogs with PDH, twice-daily administration of low-dose trilostane is an effective approach to the management of PDH. In addition, our results suggest fewer potential adverse effects if trilostane is administered twice daily in the lower dose.


Asunto(s)
Hiperfunción de las Glándulas Suprarrenales/veterinaria , Dihidrotestosterona/análogos & derivados , Enfermedades de los Perros/tratamiento farmacológico , Inhibidores Enzimáticos/uso terapéutico , Enfermedades de la Hipófisis/veterinaria , Hiperfunción de las Glándulas Suprarrenales/tratamiento farmacológico , Animales , Peso Corporal , Dihidrotestosterona/administración & dosificación , Dihidrotestosterona/uso terapéutico , Perros , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/administración & dosificación , Hidrocortisona/sangre , Enfermedades de la Hipófisis/tratamiento farmacológico
11.
J Clin Pathol ; 61(8): 962-4, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18663059

RESUMEN

Aggressive angiomyxoma (AAM) is a rare mesenchymal neoplasm that usually occurs in the pelvic-perineal region. Only two cases of AAM occurring outside this region have been reported. The case of AAM reported here originated from lung. A 70-year-old woman was admitted for evaluation of an incidentally detected pulmonary mass on chest radiography. Tumour resection under the thoracoscopy was performed. Pathological examination revealed microscopical features that were characteristic of AAM. The features were oval- to spindle-shaped tumour cells in a myxoid stroma, hyalinised thick vessels, and characteristic immunophenotype. The differential diagnosis of AAM and other mesenchymal neoplasms of lung is also discussed.


Asunto(s)
Neoplasias Pulmonares/patología , Mixoma/patología , Anciano , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Mixoma/diagnóstico por imagen , Mixoma/cirugía , Tomografía Computarizada por Rayos X
13.
Toxicol Appl Pharmacol ; 110(2): 251-8, 1991 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-1891772

RESUMEN

Subcutaneous injection of sodium dichromate into male Sprague-Dawley rats immediately produced a variety of metabolic changes in a dose-dependent manner. Serum lactate and glucose were significantly increased after dichromate treatment, reaching maximum levels at 15 and 30 min, respectively. Then, the toxicity progressively diminished. In contrast, a steady increase in blood urea nitrogen (BUN) concentration was caused by dichromate, reaching maximum levels at 60 min after the administration; elevated BUN levels were sustained for several hours thereafter. Unlike KCN (5 mg/kg, ip) and As2O3 (5 mg/kg, ip), dichromate rapidly decreased serum insulin within 15 min after intoxication in doses of 20 and 40 mg/kg; hypoinsulinemia lasted 60 min. However, insulin levels returned to the normal range at 120 min after treatment. Dichromate-induced metabolic disturbance was also observed in the 24 hr-fasted rats, the response of which was similar to normal rats except for later hyperglycemia. In both cases, the duration time was short (30 to 60 min). Adrenalectomy and insulin pretreatment had no effect on dichromate-induced hyperglycemia. These results suggest that dichromate-induced metabolic disturbance results from the concomitant effects of a sudden decrease in serum insulin level and its direct inhibitory effect on carbohydrate metabolism. In addition, the characteristic biphasic pattern of metabolic disturbance might be related to metabolic fate of dichromate in vivo.


Asunto(s)
Arsenicales , Glucemia/metabolismo , Cromatos/toxicidad , Insulina/sangre , Lactatos/sangre , Óxidos , Piruvatos/sangre , Animales , Arsénico/toxicidad , Trióxido de Arsénico , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Relación Dosis-Respuesta a Droga , Insulina/metabolismo , Insulina/farmacología , Secreción de Insulina , Masculino , Cianuro de Potasio/toxicidad , Ratas , Ratas Endogámicas , Valores de Referencia , Factores de Tiempo
14.
Arch Toxicol ; 65(7): 537-41, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1781735

RESUMEN

A comparison of the effects of intraperitoneal and subcutaneous routes of administration of sodium dichromate on nephrotoxicity in rats was studied. Dichromate when injected subcutaneously (SC group) produced a higher degree of nephrotoxicity than when administered intraperitoneally (IP group). It caused severe progressive proteinuria followed by polyuria and glucosuria, reaching maximum levels at 3 days after treatment in the SC group, whereas it produced mild proteinuria without glucosuria in the IP group. The dose-dependent increases in blood urea nitrogen (BUN) and creatinine concentrations, shown in the SC group, were not observed in the IP group. However, between the two groups, there were no great differences in either the urinary excretion rate of chromium or the electrophoretic patterns of urinary protein in the day 1 urine specimens. Pretreatment of phenobarbital (PB) had no remarkable effect on the dichromate-induced nephrotoxicity. In contrast, it potentiated dichromate-induced hepatotoxicity, the indices of which were the elevation in serum alanine aminotransferase (ALT) activity and hepatic lipid peroxide formation. These results suggest that the dependence of dichromate-induced nephrotoxicity on the route of administration is related to the chemical forms of chromium reaching the kidney, and the necrotizing property of dichromate results from its metabolic fate in vivo.


Asunto(s)
Cromatos/toxicidad , Enfermedades Renales/inducido químicamente , Alanina Transaminasa/sangre , Animales , Biotransformación , Nitrógeno de la Urea Sanguínea , Cromatos/farmacocinética , Cromo/orina , Creatinina/sangre , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Enfermedades Renales/metabolismo , Hígado/metabolismo , Masculino , Fenobarbital/uso terapéutico , Ratas , Ratas Endogámicas , Distribución Tisular
15.
Arch Biochem Biophys ; 227(2): 580-6, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6320729

RESUMEN

The nature of chloride ion as an activator of angiotensin-converting enzyme was studied by a series of kinetic experiments with hog plasma enzyme preparation. The enzyme required the presence of chloride ion for its full catalytic activity, but its requirement of monovalent anion was not absolute. The KA value for the enzyme-chloride binding was estimated to be about 150 mM in all cases regardless of the peptide substrates employed. In the presence of chloride ion, the activity of the enzyme was increased, but its optimum pH was shifted gradually to the alkaline region up to pH 8.2 depending on the concentration of chloride ion. In addition, in the presence of chloride ion, the apparent Km values were reduced markedly while the Vmax values were not much altered; for example, for the hydrolysis of angiotensin I decapeptide, the Km value decreased by a factor of 50 while only an 18% increase in Vmax was observed when the enzyme was saturated with chloride ion. The result suggests that chloride ion acts as a conformational modifier inducing the affinity of synergistic binding of substrate.


Asunto(s)
Cloruros/farmacología , Peptidil-Dipeptidasa A/sangre , Regulación Alostérica , Animales , Aniones/farmacología , Activación Enzimática/efectos de los fármacos , Concentración de Iones de Hidrógeno , Cinética , Modelos Químicos , Porcinos
16.
Arch Toxicol ; 64(8): 644-9, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2090032

RESUMEN

The effect of sodium dichromate on cellular metabolism was investigated. Intraperitoneal injection of sodium dichromate into the rat (20 or 40 mg/kg) caused significant increases in serum lactate, pyruvate, and creatinine concentrations within 15 min after intoxication. Severe hyperglycemia occurred thereafter, as a result of increased hepatic glycogenolysis, which was seen in the first 2 h after dichromate. However, liver glycogen was resynthesized in 24 h-fasted rats after glucose refeeding. Dichromate decreased serum total amino acids, with a consequent increase in blood urea nitrogen (BUN) concentration. Unlike HgCl2 (2 mg/kg, i.p.), As2O3 (5 mg/kg, i.p.), and KCN (5 mg/kg, i.p.), dichromate showed the largest metabolic disturbance only in the early period after treatment. In addition, dichromate produced cyanosis, which appeared during the period of the accelerated glycolysis and breakdown of creatinine phosphate. Regardless of chemical species, only the hexavalent chromium compounds had an effect on the cellular metabolism. Trivalent chromium compounds had no effect at all. These results suggest that dichromate possesses a characteristic dual action on cellular metabolism, which might be related to its metabolic fate.


Asunto(s)
Cromatos/toxicidad , Compuestos de Sodio , Aminoácidos/sangre , Animales , Cromo/toxicidad , Cianosis/inducido químicamente , Prueba de Tolerancia a la Glucosa , Lactatos/metabolismo , Ácido Láctico , Glucógeno Hepático/análisis , Masculino , Piruvatos/metabolismo , Ácido Pirúvico , Ratas , Ratas Endogámicas
17.
Arch Toxicol ; 66(9): 646-51, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1482288

RESUMEN

Ascorbate treatment 30 min prior to sodium dichromate (20 or 30 mg/kg, s.c.) shows higher potency than that of glutathione (GSH) in protecting against both the metabolic disturbance and nephrotoxicity induced by dichromate. However, ascorbate treatment after 2 h of dichromate intoxication had no effect on dichromate-induced blood urea nitrogen (BUN) elevation 3 days after intoxication. In contrast, dichromate-induced glucosuria, which reached maximum levels at 3 days after treatment, was significantly decreased by GSH or N-acetyl cysteine (NAC) treatment, even if its administration was after 24 h of dichromate intoxication. Pretreatment with GSH depletors such as diethyl maleate (DEM) and buthionine sulfoximine (BSO) had no effect on dichromate-induced nephrotoxicity. GSH levels in the liver and kidney were not affected at 3 h after dichromate treatment. However, dichromate significantly increased tissue GSH levels with a marked increase in liver per kidney GSH ratio at 24 h after treatment, if food was withheld subsequent to dichromate treatment, indicating that GSH biosynthesis resulted from the accelerated protein breakdown. These results suggest that GSH-mediated dichromate reduction is not a kinetically favorable pathway in vivo; however, GSH plays an important role in protection against dichromate-induced nephrotoxicity. In addition, the cellular metabolism of dichromate in the early period after treatment is important in the pathogenesis of its nephrotoxicity.


Asunto(s)
Cromatos/toxicidad , Glutatión/fisiología , Enfermedades Renales/patología , Animales , Ácido Ascórbico/farmacología , Cromatos/metabolismo , Glutatión/farmacología , Riñón/patología , Enfermedades Renales/inducido químicamente , Masculino , Oxidación-Reducción , Ratas , Ratas Sprague-Dawley , Compuestos de Sulfhidrilo/farmacología
18.
Catheter Cardiovasc Interv ; 50(1): 34-9, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10816277

RESUMEN

One of the major limitations in coronary intervention is restenosis. This study was aimed to identify clinical, angiographic, and procedural factors that may be related to the second restenosis (SR). We studied 101 patients who underwent more than two follow-up coronary angiograms after two coronary interventions between January 1996 and December 1998 in Chonnam University Hospital (out of 4,092 total coronary interventions in 3,030 patients during the same period). The patients were divided into two groups according to the evidence of SR. Fifty-two patients (group A: 57+/-10 years, M:F = 44:8) who had SR and the other 49 patients (group B: 54+/-9 years, M:F = 44:5) without SR were analyzed. Clinical features, angiographic characteristics, coronary interventional procedures, and other risk factors were compared between two groups by univariate analysis and multivariate stepwise logistic regression analysis was performed for the predictive factors for SR. The clinical variables of age, sex, clinical diagnosis, and risk factors were not different between two groups. The lesion severer than B(2) by AHA/ACC classification were associated with SR (P<0.05). Recurrent angina as an indication for follow-up angiography was associated with SR (P<0.01). Predictive factors associated with SR were patient's subjective symptom and lesion severer than type B(2) according to AHA/ACC classification.


Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Enfermedad Coronaria/terapia , Anciano , Análisis de Varianza , Angioplastia Coronaria con Balón/métodos , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Recurrencia , Retratamiento , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Stents , Tasa de Supervivencia
19.
J Korean Med Sci ; 16(4): 509-11, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11511799

RESUMEN

A 61-yr-old male patient presented with severe chest pain with cardiogenic shock due to an extensive anterolateral myocardial infarction. Two-dimensional echocardiogram showed severe left ventricular systolic dysfunction (ejection fraction=17%). Emergent coronary angiogram obtained immediately after placing temporary pacing electrode revealed total thrombotic occlusion in the left main stem. We performed direct coronary intervention using kissing balloon technique with the aid of Abciximab (ReoPro) infusion. Residual stenosis with thrombus remained even after high pressure balloon dilatations, therefore we placed two stents, one in the ostia of left anterior descending (LAD) and the other in left circumflex artery (LCX). Coronary angiogram after kissing stents showed improved LAD and LCX flows without residual stenosis. Chest pain resolved and blood pressure normalized after coronary intervention. The whole procedure time was 15 min. Follow-up coronary angiogram taken one week later showed patent previous stented arteries, and echocardiography demonstrated 40% of left ventricular ejection fraction. The clinical course for one-year follow-up was uneventful.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Enfermedad Coronaria/terapia , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Stents , Abciximab , Humanos , Masculino , Persona de Mediana Edad
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