RESUMO
Weanling male Wistar rats fed a choline-deficient diet develop acute kidney injury. Menhaden oil, which is a very important source of omega-3 fatty acids, has a notorious protective effect. The mechanism of this protection is unknown; one possibility could be that menhaden oil changes renal lipid profile, with an impact on the functions of biological membranes. The aim of this work was to study the renal lipid profile in rats fed a choline-deficient diet with menhaden oil or vegetable oil as lipids. Rats were divided into 4 groups and fed four different diets for 7 days: choline-deficient or choline-supplemented diets with corn and hydrogenated oils or menhaden oil. Serum homocysteine, vitamin B12, and folic acid were analyzed. Renal lipid profile, as well as the fatty acid composition of the three oils, was measured. Choline-deficient rats fed vegetable oils showed renal cortical necrosis. Renal omega-6 fatty acids were higher in rats fed a cholinedeficient diet and a choline-supplemented diet with vegetable oils, while renal omega-3 fatty acids were higher in rats fed a choline-deficient diet and a choline-supplemented diet with menhaden oil. Rats fed menhaden oil diets had higher levels of renal eicosapentaenoic and docosahexaenoic acids. Renal myristic acid was increased in rats fed menhaden oil. The lipid renal profile varied quickly according to the type of oil present in the diet.
Assuntos
Injúria Renal Aguda/metabolismo , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/farmacologia , Óleos de Peixe/administração & dosagem , Óleos de Peixe/farmacologia , Rim/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Injúria Renal Aguda/etiologia , Animais , Colina/administração & dosagem , Deficiência de Colina/complicações , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Rim/patologia , Masculino , Ácido Mirístico/metabolismo , Óleos de Plantas/administração & dosagem , Óleos de Plantas/farmacologia , Ratos WistarRESUMO
Weanling Sprague-Dawley rats were fed on a choline-deficient diet with hydrogenated vegetable oil and corn oil as lipids develop acute renal failure. Pathogenesis of the latter is controversial and an ischemic mechanism has been proposed. Arachidonic acid derivatives are involved in the regulation of vascular tonus. Vasospasm could be due to an increase in tromboxane A2-mediated vasoconstriction or to a decrease in prostacyclin-induced vasodilatation. Enzymes involved in the synthesis of both compounds are tromboxane A2- and prostacyclin-synthase respectively. The aim of this study was to identify the variable number tandem repeats (VNTR) in the promoter region of prostacyclin synthase gene and verify if there exists a relationship between the occurrence of VNTR in those choline-deficient rats which die because of acute renal failure and those which do not. We verified the presence of the VNTR in the prostacyclin synthase rat gene, but we did not find any difference in the molecular weight of the alleles between experimental and control rats. Renal reparation of the acute kidney injury due to choline deficiency in some rats is not related with differences in VNTR in the promoter region of the prostacyclin synthase gene.
Assuntos
Deficiência de Colina/genética , Sistema Enzimático do Citocromo P-450/genética , Oxirredutases Intramoleculares/genética , Repetições Minissatélites , Regiões Promotoras Genéticas , Injúria Renal Aguda/fisiopatologia , Animais , Dieta , Feminino , Humanos , Masculino , Gravidez , Ratos , Ratos Sprague-DawleyRESUMO
Weanling Sprague-Dawley rats were fed on a choline-deficient diet with hydrogenated vegetable oil and corn oil as lipids develop acute renal failure. Pathogenesis of the latter is controversial and an ischemic mechanism has been proposed. Arachidonic acid derivatives are involved in the regulation of vascular tonus. Vasospasm could be due to an increase in tromboxane A2-mediated vasoconstriction or to a decrease in prostacyclin-induced vasodilatation. Enzymes involved in the synthesis of both compounds are tromboxane A2- and prostacyclin-synthase respectively. The aim of this study was to identify the variable number tandem repeats (VNTR) in the promoter region of prostacyclin synthase gene and verify if there exists a relationship between the occurrence of VNTR in those choline-deficient rats which die because of acute renal failure and those which do not. We verified the presence of the VNTR in the prostacyclin synthase rat gene, but we did not find any difference in the molecular weight of the alleles between experimental and control rats. Renal reparation of the acute kidney injury due to choline deficiency in some rats is not related with differences in VNTR in the promoter region of the prostacyclin synthase gene.
Assuntos
Humanos , Masculino , Animais , Feminino , Gravidez , Ratos , Deficiência de Colina/genética , Oxirredutases Intramoleculares/genética , /genética , Dieta , Repetições Minissatélites , Ratos Sprague-DawleyRESUMO
Weanling Sprague-Dawley rats were fed on a choline-deficient diet with hydrogenated vegetable oil and corn oil as lipids develop acute renal failure. Pathogenesis of the latter is controversial and an ischemic mechanism has been proposed. Arachidonic acid derivatives are involved in the regulation of vascular tonus. Vasospasm could be due to an increase in tromboxane A2-mediated vasoconstriction or to a decrease in prostacyclin-induced vasodilatation. Enzymes involved in the synthesis of both compounds are tromboxane A2- and prostacyclin-synthase respectively. The aim of this study was to identify the variable number tandem repeats (VNTR) in the promoter region of prostacyclin synthase gene and verify if there exists a relationship between the occurrence of VNTR in those choline-deficient rats which die because of acute renal failure and those which do not. We verified the presence of the VNTR in the prostacyclin synthase rat gene, but we did not find any difference in the molecular weight of the alleles between experimental and control rats. Renal reparation of the acute kidney injury due to choline deficiency in some rats is not related with differences in VNTR in the promoter region of the prostacyclin synthase gene.(AU)
Assuntos
Humanos , Masculino , Animais , Feminino , Gravidez , Ratos , Deficiência de Colina/genética , Sistema Enzimático do Citocromo P-450/genética , Oxirredutases Intramoleculares/genética , Dieta , Repetições Minissatélites , Ratos Sprague-DawleyRESUMO
Lymph node mapping and sentinel lymph node biopsy are currently used to stage patients with cutaneous malignant melanoma. Immunohistochemical stains contribute to the detection of micrometastases; however, molecular biology techniques are associated with better diagnostic sensitivity. Sixty sentinel lymph nodes were included in this study. The primary lesions were malignant melanoma stage I or II, with a follow-up of longer than 2 years. Sentinel lymph nodes were studied with hematoxylin-eosin, immunohistochemistry for S-100 and HMB-45, and molecular biology techniques (reverse transcription (RT)-PCR) for the detection of tyrosinase messenger RNA. In 15 of 60 cases (25%), tyrosinase was detected by RT-PCR; three of these cases were also positive by immunohistochemistry. The population was divided into three groups: (i) hematoxylin-eosin-/immunohistochemistry+/molecular biology techniques+ (3 cases); (ii) hematoxylin-eosin-/immunohistochemistry-/molecular biology techniques+ (12 cases); (iii) hematoxylin-eosin-/immunohistochemistry-/molecular biology techniques- (45 cases). Correlation of the groups with overall survival showed the following: (i) 2 of 3 patients died (67%); (ii) 5 of 12 died (42%), and (iii) all 45 patients are alive, with no lymphadenectomy and a median follow-up of 84 months. The inclusion of molecular biology techniques appears to be of great value for the detection of sentinel lymph node micrometastases in patients with cutaneous malignant melanoma. In our series, those patients who showed negativity with all the three methods had a null recurrence rate. Therefore, this triple negativity could be a positive prognostic factor for overall survival. Our findings suggest the possibility of molecular oncological staging, which would allow the selection of patients with submicroscopic metastases for a complete treatment.
Assuntos
Melanoma/patologia , Metástase Neoplásica/diagnóstico , Estadiamento de Neoplasias/métodos , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias , Feminino , Humanos , Imuno-Histoquímica , Linfonodos/metabolismo , Linfonodos/patologia , Masculino , Melanoma/mortalidade , Melanoma/cirurgia , Antígenos Específicos de Melanoma , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/biossíntese , Monofenol Mono-Oxigenase/genética , Proteínas de Neoplasias/biossíntese , Prognóstico , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas S100/biossíntese , Sensibilidade e Especificidade , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/cirurgiaRESUMO
INTRODUCTION: Lymph node status in patients with cutaneous malignant melanoma is the most important prognostic factor. Patients with clinically positive nodes (stage III) should undergo therapeutic lymphadenectomy; however, the surgical approach to the regional disease in patients with negative clinical examination (stage I and II) is still controversial. Selective lymphadenectomy consists of the intraoperative identification of the first node in the nodal basin, the sentinel lymph node (SLN). Routine examination, serial sectioning, and immunohistochemistry may underestimate the presence of tumor cells. PCR is a molecular biology technique that may be useful for the detection of malignant melanoma nodal metastases in the SLN. AIM: The aim of this study was to use tyrosinase messenger RNA (mRNA) amplification for the detection of micrometastases in fresh frozen SLNs. METHODS: 46 hematoxylin-eosin (HE)-negative sentinel node samples from 42 patients with malignant melanoma were included in this study. Formalin-fixed paraffin-embedded sections were immunostained with S-100 protein and HMB-45. A central portion of the node was submitted for PCR. This method was accomplished with a combination of reverse transcription and amplification of the tyrosinase complementary DNA and double- round PCR (nested reverse transcriptase [RT]-PCR). RESULTS: In 1 of the 42 SLN-negative patients, immunohistochemistry stains allowed the detection of micrometastases. With molecular biology, 14 of the 42 SLN patients were positive (33%); in another 12 (29%), only the nested RT-PCR was positive. Of the 42 patients, 24 were put into 3 groups and followed for a 5-year period with 1, 7, and 16 patients, respectively, in the groups. The first group involved 1 patient who had provided 2 SLN samples that were found to be SLN-positive using both techniques, immunohistochemistry stains and nested RT-PCR (he had hepatic metastasis and died 24 months after diagnosis). The second group, with only nested RT-PCR positive SLN samples, included 7 of 12 patients who were followed and had a median survival of 37 months; 4 died of widespread metastatic disease, the other 3 patients had event-free survival, but 1 consented to undergo a therapeutic lymphadenectomy as a result of a positive test. The last group consisting of 16 of 32 patients, with complete 5-year survival, who were SLN-negative with both techniques, immunohistochemistry stains and nested RT-PCR. Fourteen of the 16 (88%) were event-free survival during the follow-up, and 2 had local relapse. CONCLUSION: Tyrosinase mRNA amplification may be a negative prognostic factor for the detection of micrometastases in fresh frozen SLNs using molecular biology techniques.
Assuntos
Linfonodos/patologia , Metástase Linfática/diagnóstico , Melanoma/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Neoplasias Cutâneas/patologia , Seguimentos , Humanos , Linfonodos/cirurgia , Melanoma/mortalidade , Monofenol Mono-Oxigenase/genética , Estadiamento de Neoplasias , RNA Mensageiro/análise , Neoplasias Cutâneas/mortalidade , Taxa de SobrevidaRESUMO
El estudio del ganglio centinela (GC) es esencial en pacientes con melanoma maligno cutáneo estadio I y II ya que provee información indispensable para la correcta estadificación y tratamiento cuando se detectan micrometástasis (linfadenectomía selectiva). Los protocolos para el manejo de los GC deben incluir métodos complementarios que permitan aumentar al máximo la sensibilidad para la detección de micrometástasis, teniendo en cuenta que esta demostrado que con el estudio rutinario se obtiene un número importante de falsos negativos. Estudiamos 240 GC pertenecientes a 162 pacientes con melanoma maligno cutáneo estadios I y II. Los mismos fueron hemiseccionados intraoperatoriamente seleccionándose una lonja central para el estudio de biología molecular, la que fue consevada a -70ºC. El resto del material fue procesado rutinariamente obteniéndose cortes seriados para hematoxilina-eosina (HE) e inmunohistoquímica (IHQ). Los anticuerpos utilizados fueron HMB-45 (DAKO, 1:50) y proteína S-100 (Biogenex, 1:400). 39 GC negativos con HE fueron estudiados con el método de reacción en cadena de polimerasa-transcriptasa reversa (RT-PCR) para la detección del ARNm de la tirosinasa. Se realizaron los controles negativos, positivos y de la integridad del ARN. La presencia de micrometástasis fue correlacionada con el grosor del melanoma cutáneo menor o mayor de 1,5 mm... (TRUNCADO)(AU)
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Melanoma/cirurgia , Melanoma/epidemiologia , Melanoma/mortalidade , Melanoma/terapia , Metástase Linfática/diagnóstico , Linfonodos/patologia , Excisão de Linfonodo , Hematoxilina , Imuno-Histoquímica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Mensageiro , Monofenol Mono-Oxigenase , Estadiamento de Neoplasias , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/mortalidadeRESUMO
El estudio del ganglio centinela (GC) es esencial en pacientes con melanoma maligno cutáneo estadio I y II ya que provee información indispensable para la correcta estadificación y tratamiento cuando se detectan micrometástasis (linfadenectomía selectiva). Los protocolos para el manejo de los GC deben incluir métodos complementarios que permitan aumentar al máximo la sensibilidad para la detección de micrometástasis, teniendo en cuenta que esta demostrado que con el estudio rutinario se obtiene un número importante de falsos negativos. Estudiamos 240 GC pertenecientes a 162 pacientes con melanoma maligno cutáneo estadios I y II. Los mismos fueron hemiseccionados intraoperatoriamente seleccionándose una lonja central para el estudio de biología molecular, la que fue consevada a -70ºC. El resto del material fue procesado rutinariamente obteniéndose cortes seriados para hematoxilina-eosina (HE) e inmunohistoquímica (IHQ). Los anticuerpos utilizados fueron HMB-45 (DAKO, 1:50) y proteína S-100 (Biogenex, 1:400). 39 GC negativos con HE fueron estudiados con el método de reacción en cadena de polimerasa-transcriptasa reversa (RT-PCR) para la detección del ARNm de la tirosinasa. Se realizaron los controles negativos, positivos y de la integridad del ARN. La presencia de micrometástasis fue correlacionada con el grosor del melanoma cutáneo menor o mayor de 1,5 mm... (TRUNCADO)
