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1.
Curr Oncol ; 27(1): e53-e56, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32218668

RESUMO

Renal medullary carcinoma (rmc) is a rare and aggressive renal malignancy that usually presents at an advanced stage, has a poor prognosis, and is associated with sickle cell trait. We present a case of rmc including radiologic and pathology findings, treatment, and outcome. A review of the literature is also presented, with an emphasis on the association of rmc with sickle cell trait, which was an unknown diagnosis in our patient preoperatively.


Assuntos
Sobreviventes de Câncer/estatística & dados numéricos , Carcinoma Medular/complicações , Neoplasias Renais/complicações , Traço Falciforme/complicações , Adolescente , Carcinoma Medular/mortalidade , Criança , Feminino , Humanos , Neoplasias Renais/mortalidade , Masculino , Pessoa de Meia-Idade , Traço Falciforme/mortalidade , Traço Falciforme/patologia , Adulto Jovem
2.
Br J Cancer ; 120(8): 861-863, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30890774

RESUMO

African-American (AA) cancer patients have long-experienced worse outcomes compared to non-Hispanic whites (NHW). No studies to date have evaluated the prognostic impact of sickle cell trait (SCT) and other inherited haemoglobinopathies, of which several are disproportionately high in the AA population. In a cohort analysis of treated patients diagnosed with breast or prostate cancer in the linked SEER-Medicare database, the relative risk (RR) for ≥1 serious adverse events (AEs), defined as hospitalisations or emergency department visits, was estimated for 371 AA patients with a haemoglobinopathy (AA+) compared to patients without haemoglobinopathies (17,303 AA-; 144,863 NHW-). AA+ patients had significantly increased risk for ≥1 AEs compared to AA- (RR = 1.19; 95% CI 1.11-1.27) and NHW- (RR = 1.23; 95% CI 1.15-1.31) patients. The magnitude of effect was similar by cancer type, and in analyses of AA+ with SCT only. Our findings suggest a novel hypothesis for disparities in cancer outcomes.


Assuntos
Negro ou Afro-Americano , Hemoglobinopatias/epidemiologia , Neoplasias/epidemiologia , Traço Falciforme/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Hemoglobinopatias/sangue , Hemoglobinopatias/complicações , Hemoglobinopatias/patologia , Humanos , Masculino , Medicare , Neoplasias/sangue , Neoplasias/complicações , Neoplasias/patologia , Pacientes , Fatores de Risco , Programa de SEER , Traço Falciforme/sangue , Traço Falciforme/complicações , Traço Falciforme/patologia , Estados Unidos/epidemiologia , População Branca
3.
Pathol Int ; 69(4): 241-245, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30843648

RESUMO

Renal medullary carcinoma (RMC) is a rare and aggressive cancer associated with the sickle cell trait. The diagnosis of RMC depends on recognition of its histologic features and immunohistochemical deficiency of INI1, but correct diagnosis is sometimes difficult, especially if a patient's information on race, past, and family medical history is unclear. At present, this is the first report on RMC in Japan.


Assuntos
Carcinoma Medular/diagnóstico por imagem , Carcinoma de Células Renais/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Traço Falciforme/diagnóstico por imagem , Adulto , Carcinoma Medular/genética , Carcinoma Medular/patologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Japão , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , Proteína SMARCB1/metabolismo , Traço Falciforme/patologia , Tomografia Computadorizada por Raios X , Adulto Jovem
4.
Anticancer Res ; 38(6): 3757-3761, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29848739

RESUMO

Renal medullary carcinoma (RMC) is an aggressive high-grade renal cell carcinoma (RCC) associated almost exclusively with sickle cell trait or sickle cell disease. However, RCC with RMC features has rarely been reported in patients with no sickle cell trait or disease. Renal cell carcinoma unclassified with medullary phenotype (RCCU-MP) is a newly-coined term used by an international panel of experts to describe renal cell carcinoma showing morphologic and immunohistochemical features of renal medullary carcinoma in patients without sickle cell trait/disease. So far, only one study in the English literature has described five such cases. Here, we report a case with unique clinical and pathological features in a 76-year-old male patient without sickle cell trait. The patient had a history of colon cancer with liver and lung metastases and was found to have a new renal mass in his right kidney during the follow up. A right nephrectomy was performed and showed two separate masses (tumor 1 and tumor 2). Tumor 1 had histologic features of RMC and the tumor cells were positive for CK7, Pax8, and OCT4 and showed loss of nuclear INI1 expression. Tumor 1 was diagnosed as RCCU-MP (6.3 cm, pT3aNx, WHO/ISUP nuclear grade 3). Tumor 2 showed features of clear cell type of RCC (0.6 cm, pT1aNx, WHO/ISUP grade 2) with intact nuclear INI1 expression. Three-months post-nephrectomy, the patient developed lung metastasis of RCCU-MP. To the best of our knowledge, this was the first documented case with synchronous RCCU-MP and clear cell RCC presenting in a patient without sickle cell trait. Careful histologic assessment with a panel of immunohistochemical biomarkers was helpful to render a correct diagnosis for early aggressive treatment.


Assuntos
Carcinoma de Células Renais/patologia , Medula Renal/patologia , Neoplasias Renais/patologia , Rim/patologia , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/cirurgia , Humanos , Rim/metabolismo , Rim/cirurgia , Medula Renal/metabolismo , Medula Renal/cirurgia , Neoplasias Renais/metabolismo , Neoplasias Renais/cirurgia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Masculino , Nefrectomia/métodos , Fenótipo , Traço Falciforme/patologia
6.
J Hematol Oncol ; 10(1): 119, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28610635

RESUMO

BACKGROUND: Sickle cell disease (SCD) is a disorder of red blood cells (RBCs) expressing abnormal hemoglobin-S (HbS) due to genetic inheritance of homologous HbS gene. However, people with the sickle cell trait (SCT) carry a single allele of HbS and do not usually suffer from SCD symptoms, thus providing a rationale to treat SCD. METHODS: To validate gene therapy potential, hematopoietic stem cells were isolated from the SCD patient blood and treated with CRISPR/Cas9 approach. To precisely dissect genome-editing effects, erythroid progenitor cells were cloned from single colonies of CRISPR-treated cells and then expanded for simultaneous gene, protein, and cellular function studies. RESULTS: Genotyping and sequencing analysis revealed that the genome-edited erythroid progenitor colonies were converted to SCT genotype from SCD genotype. HPLC protein assays confirmed reinstallation of normal hemoglobin at a similar level with HbS in the cloned genome-edited erythroid progenitor cells. For cell function evaluation, in vitro RBC differentiation of the cloned erythroid progenitor cells was induced. As expected, cell sickling assays indicated function reinstitution of the genome-edited offspring SCD RBCs, which became more resistant to sickling under hypoxia condition. CONCLUSIONS: This study is an exploration of genome editing of SCD HSPCs.


Assuntos
Anemia Falciforme/genética , Anemia Falciforme/terapia , Sistemas CRISPR-Cas , Eritrócitos/metabolismo , Edição de Genes/métodos , Células-Tronco Hematopoéticas/metabolismo , Anemia Falciforme/patologia , Antígenos CD34/análise , Linhagem Celular , Células Cultivadas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Eritrócitos/citologia , Eritrócitos/patologia , Células Eritroides/citologia , Células Eritroides/metabolismo , Células Eritroides/patologia , Eritropoese , Terapia Genética/métodos , Genótipo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Hemoglobina Falciforme/análise , Hemoglobina Falciforme/genética , Hemoglobinas/análise , Hemoglobinas/genética , Humanos , Traço Falciforme/genética , Traço Falciforme/patologia
7.
Salvador; s.n; 2016. 61 p. ilus, tab, map.
Tese em Português | LILACS | ID: biblio-1001035

RESUMO

INTRODUÇÃO: A doença renal crônica (DRC) é uma doença grave que atinge cerca de 10% da população mundial. Devido à perda irreversível da função dos rins, os pacientes precisam do tratamento dialítico e desde 2010, no Brasil, a taxa de pacientes em diálise cresce de 3% cada ano. Cerca 93% do tratamento está financiado pelo SUS o que corresponde a 10% do orçamento do Ministério da Saúde. As principais causas de DRC no Brasil e no mundo são diabetes mellitus (DM) e hipertensão arterial sistêmica (HAS), seguido de glomerulopatias. As alterações podem ser complicadas por condições de hipóxia tecidual, as quais podem ser intensificadas pela doença falciforme. Os indivíduos com traço falciforme podem apresentar esse quadro clínico em condições extremas como um esforço físico intenso e prolongado. OBJETIVO: O objetivo deste estudo foi investigar a associação entre o traço falciforme e a progressão de DRC em Salvador-BA. MATERIAL E MÉTODOS: Foi desenvolvido um estudo de corte transversal, no qual no período de maio de 2014 até novembro de 2015...


INTRODUCTION: Chronic Kidney Disease (CKD) is a serious disease that affects about 10% of world population. It is due to irreversible loss of kidney function, so necessitating the patient’s need of dialysis treatment and since 2010, in Brazil, the rate of patients on dialysis is growing by 3% each year. About 93% of the treatment is funded by SUS which corresponds to 10% of the Health Ministry´s budget. The main causes of CKD in Brazil and in the world are diabetes mellitus and arterial hypertension, followed by glomerulopathies. The alterations can be complicated by conditions of tissue hypoxia, which can be intensified by the sickle cell disease. Individuals with sickle cell trait, although asymptomatic may present these clinical features in extreme conditions such as intense and prolonged physical activities. AIM: The aim of this study was to investigate the association between sickle cell trait and progression of CKD in patients on hemodialysis (HD) in Salvador, Bahia. MATERIAL AND METHODS: A cross-sectional cohort study was conducted from May 2014 to November 2015...


Assuntos
Humanos , Diálise Renal/métodos , Diálise Renal , Nefropatias/imunologia , Nefropatias/mortalidade , Nefropatias/patologia , Nefropatias/prevenção & controle , Traço Falciforme/diagnóstico , Traço Falciforme/patologia , Traço Falciforme/prevenção & controle
9.
Salvador; s.n; 2015. 61 p. ilus.
Tese em Português | LILACS | ID: biblio-870331

RESUMO

INTRODUÇÃO: A doença renal crônica (DRC) é uma doença grave que atinge cercade 10% da população mundial. Devido à perda irreversível da função dos rins, os pacientes precisam do tratamento dialítico e desde 2010, no Brasil, a taxa de pacientes em diálise cresce de 3% cada ano. Cerca 93% do tratamento está financiado pelo SUS o que corresponde a 10% do orçamento do Ministério da Saúde. As principais causas de DRC no Brasil e no mundo são diabetes mellitus (DM) e hipertensão arterial sistêmica (HAS), seguido de glomerulopatias. As alterações podem ser complicadas por condições de hipóxia tecidual, as quais podem ser intensificadas pela doença falciforme. Os indivíduos com traço falciforme podem apresentar esse quadro clínico em condições extremas como um esforço físico intenso e prolongado. OBJETIVO: O objetivo deste estudo foi investigar a associação entre o traço falciforme e a progressão de DRC em Salvador-BA. MATERIAL E MÉTODOS: Foi desenvolvido um estudo de corte transversal, no qual no período de maio de 2014 até novembro de 2015; foram incluídos 306 indivíduos portadores de DRC em programa de hemodiálise nos hospitais e clínicas de referência tais como, Instituto de Nefrologia e Diálise (INED), Hospital Ana Nery (HAN) e Hospital Geral Roberto Santos (HGRS) há no máximo três anos. cinco mililitros (mL) de sangue total foram coletados em cada paciente para a caracterização do perfil de hemoglobinas variantes pela técnica de cromatografia líquida de alta eficiência (HPLC). Como grupo controle, foram utilizados os resultados dos testes de triagem neonatal do APAE realizados em recém-nascidos em Salvador de 2012-2014. RESULTADOS: A frequência de HbAS foi significamente maior nos pacientes em hemodiálise (10,2%) em comparação ao grupo controle (5,05%) OR: 2,04 IC 95% (1,35–2,99). Quando comparamos os pacientes com DRC com e sem traço falciforme, não houve diferença em relação à distribuição do sexo (homens 57,6% vs 50%, respectivamente, p = 0,43). A média de idade não foi diferente entre os dois grupos (52 ± 1 anos vs 56 ± 2, p = 0,21).CONCLUSÕES: A frequência do traço falciforme é maior em pacientes portadores de DRC em programa de hemodiálise em comparação à população geral. Estudos que avaliam o impacto e fisiopatologia da doença renal em indivíduos portadores de traço falciforme podem fornecer informações importantes para desenvolvimento de estratégias de prevenção da progressão para estágio final da doença renal.


INTRODUCTION: Chronic Kidney Disease (CKD) is a serious disease that affects about 10% of world population. It is due to irreversible loss of kidney function, so necessitating the patient’s need of dialysis treatment and since 2010, in Brazil, the rate of patients on dialysis is growing by 3% each year. About 93% of the treatment is funded by SUS which corresponds to 10% of the Health Ministry´s budget. The main causes of CKD in Brazil and in the world are diabetes mellitus and arterial hypertension, followed by glomerulopathies. The alterations can be complicated by conditions of tissue hypoxia, which can be intensified by the sickle cell disease. Individuals with sickle cell trait, although asymptomatic may present these clinical features in extreme conditions such as intense and prolonged physical activities. AIM: The aim of this study was to investigate the association between sickle cell trait and progression of CKD in patients on hemodialysis (HD) in Salvador, Bahia. MATERIAL AND METHODS: A cross-sectional cohort study was conducted from May 2014 to November 2015. The subjects consisted of 394 of both sexes with chronic renal failure on hemodialysis sessions for up to three years and treated in hospitals and clinics of reference such as the Institute of Nephrology and Dialysis (INED), Ana Nery’s Hospital (HAN) and Roberto Santos General Hospital (HGRS). 5mls of whole blood was collected from each patient to characterize the hemoglobin variants profile by High Performance Liquid Chromatography (HPLC). As a control group, the results of neonatal screening tests of APAE performed on newborns in Salvador 2012-2014 were used. RESULTS: The frequency of HbAS was significantly higher in hemodialysis patients (10.2%) compared to the control group (5.05%) OR: 2.04 95% CI (1.35 to 2.99). When comparing patients with CKD with and without sickle cell trait, there was no difference in relation to the distribution of sex (men 57.6% vs 50%, respectively, p = 0.43). The mean age was not different between the two groups (52 ± 1 years vs 56 ± 2, p = 0.21)...


Assuntos
Humanos , Diálise Renal/métodos , Diálise Renal , Nefropatias/imunologia , Nefropatias/mortalidade , Nefropatias/patologia , Nefropatias/prevenção & controle , Traço Falciforme/diagnóstico , Traço Falciforme/patologia , Traço Falciforme/prevenção & controle
11.
J Pediatr Hematol Oncol ; 36(5): e285-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24517963

RESUMO

Renal medullary carcinoma (RMC) is a rare neoplasm of the kidney that has been recently described. It is almost exclusive to young patients of African descent and associated with sickle cell hemoglobinopathy, mainly sickle cell trait and hemoglobin sickle cell disease. The prognosis of RMC is very poor because of the highly aggressive behavior of this neoplasm and its resistance to conventional chemotherapy. Metastatic disease is almost universal at the time of presentation, and the malignancy is minimally responsive to a variety of regimens and/or modalities, including surgery, radiotherapy, chemotherapy, and biological immune-modulation therapy. We report the seventh case of a left RMC occurring in a white child with sickle cell trait, but with a localization of the tumor in the left kidney, considered a nonpredominant side for this type of tumor.


Assuntos
Carcinoma Medular/patologia , Neoplasias Renais/patologia , Traço Falciforme/complicações , Adolescente , Humanos , Masculino , Prognóstico , Traço Falciforme/patologia
12.
Free Radic Biol Med ; 67: 377-86, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24316370

RESUMO

Red blood cells (RBCs) contain large amounts of iron and operate in highly oxygenated tissues. As a result, these cells encounter a continuous oxidative stress. Protective mechanisms against oxidation include prevention of formation of reactive oxygen species (ROS), scavenging of various forms of ROS, and repair of oxidized cellular contents. In general, a partial defect in any of these systems can harm RBCs and promote senescence, but is without chronic hemolytic complaints. In this review we summarize the often rare inborn defects that interfere with the various protective mechanisms present in RBCs. NADPH is the main source of reduction equivalents in RBCs, used by most of the protective systems. When NADPH becomes limiting, red cells are prone to being damaged. In many of the severe RBC enzyme deficiencies, a lack of protective enzyme activity is frustrating erythropoiesis or is not restricted to RBCs. Common hereditary RBC disorders, such as thalassemia, sickle-cell trait, and unstable hemoglobins, give rise to increased oxidative stress caused by free heme and iron generated from hemoglobin. The beneficial effect of thalassemia minor, sickle-cell trait, and glucose-6-phosphate dehydrogenase deficiency on survival of malaria infection may well be due to the shared feature of enhanced oxidative stress. This may inhibit parasite growth, enhance uptake of infected RBCs by spleen macrophages, and/or cause less cytoadherence of the infected cells to capillary endothelium.


Assuntos
Antioxidantes/metabolismo , Eritrócitos/metabolismo , Glutationa/metabolismo , NADP/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Anemia Hemolítica/metabolismo , Anemia Hemolítica/patologia , Eritrócitos/patologia , Eritropoese , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/patologia , Humanos , Malária/metabolismo , Malária/prevenção & controle , Oxirredução , Estresse Oxidativo , Traço Falciforme/metabolismo , Traço Falciforme/patologia , Talassemia/metabolismo , Talassemia/patologia
13.
J Appl Physiol (1985) ; 113(4): 549-56, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22700803

RESUMO

To assess the effects of regular physical activity on muscle functional characteristics of carriers of sickle cell trait (SCT), 39 untrained (U) and trained (T) hemoglobin (Hb)AA (CON) and SCT subjects (U-CON, n = 12; U-SCT, n = 8; T-CON, n = 10; and T-SCT, n = 9) performed a graded exercise and a time to exhaustion (T(ex)) test, and were subjected to a muscle biopsy. Maximal power, total work performed during T(ex), citrate synthase and cytochrome c oxidase (COX) activities, respiratory chain complexes I and IV content, and capillary density (CD), diameter (COD), and surface area (CSA) were upregulated by the same proportion in T-CON and T-SCT compared with their untrained counterparts. These proportionally similar differences imply that the observed discrepancies between U-SCT and U-CON remained in the trained subjects. Specifically, both CD and COX remained and tended to remain lower, and both COD and CSA remained and tended to remain higher in T-SCT than in T-CON. Besides, carriers of SCT displayed specific adaptations with regular physical activity: creatine kinase activity; complexes II, III, and V content; and type I fiber surface area and capillary tortuosity were lower or unchanged in T-SCT than in U-SCT. In summary, our results show that 1) carriers of SCT adapted almost similarly to CON to regular physical activity for most of the studied muscle characteristics, 2) oxidative potential remains altered in physically active carriers of SCT compared with HbAA counterparts, and 3) the specific remodeling of muscle microvascular network persists in the trained state.


Assuntos
Capilares/fisiopatologia , Metabolismo Energético , Exercício Físico , Microcirculação , Contração Muscular , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/fisiopatologia , Traço Falciforme/fisiopatologia , Adaptação Fisiológica , Adulto , Biópsia , Citrato (si)-Sintase/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Teste de Esforço , Hemoglobina A/genética , Hemoglobina A/metabolismo , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , Heterozigoto , Humanos , Masculino , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Força Muscular , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Resistência Física , Fluxo Sanguíneo Regional , Comportamento Sedentário , Traço Falciforme/sangue , Traço Falciforme/genética , Traço Falciforme/metabolismo , Traço Falciforme/patologia , Fatores de Tempo , Adulto Jovem
15.
Blood Cells Mol Dis ; 47(2): 117-9, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21592828

RESUMO

Lighter cells from density fractionated erythrocytes of sickle cell disease (SCD) patients carry higher amount of externalized phosphatidylserine (PS) and cell surface glycophorins compared to the denser counterparts. Further analysis also revealed that the denser cells contained higher levels of fetal hemoglobin (HbF) compared to the lighter cells, supported by the presence of larger number of F-cells in these populations. In this report, we have found direct evidence on the higher survival of the HbF rich erythrocytes in SCD.


Assuntos
Anemia Falciforme/metabolismo , Membrana Celular/química , Eritrócitos/metabolismo , Hemoglobina Fetal/análise , Traço Falciforme/metabolismo , Adulto , Anemia Falciforme/patologia , Anexina A5/análise , Contagem de Células , Membrana Celular/metabolismo , Separação Celular , Criança , Envelhecimento Eritrocítico , Contagem de Eritrócitos , Eritrócitos/patologia , Citometria de Fluxo , Glicoforinas/análise , Humanos , Fosfatidilserinas/análise , Povidona , Traço Falciforme/patologia , Dióxido de Silício
17.
J Appl Physiol (1985) ; 109(3): 728-34, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20576843

RESUMO

Previous studies have shown that subjects with sickle cell trait (SCT), alpha-thalassemia (alpha-t), and the dual hemoglobinopathy (SCT/alpha-t) manifest subtle, albeit significant, differences during exercise. To better understand such differences, we assessed skeletal muscle histomorphological and energetic characteristics in 10 control HbAA subjects (C), 5 subjects with alpha-t (alpha-t), 6 SCT carriers (SCT) and 9 SCT carriers with alpha-t (SCT/alpha-t). Subjects underwent a muscle biopsy and also performed an incremental maximal exercise and a time to exhaustion test. There were no observable differences in daily energy expenditure, maximal power output (Pmax), or time to exhaustion at 110% Pmax (Tex) among the groups. Blood lactate concentrations measured at the end of the Tex, muscle fiber type distribution, and mean phosphofructokinase (PFK), lactate dehydrogenase (LDH), beta-hydroxyacyl-CoA-dehydrogenase (HAD), and citrate synthase (CS) activities were all similar among the four groups. However, SCT was associated with a lower cytochrome-c oxidase (COx) activity in type IIa fibers (P<0.05), and similar trends were observed in fiber types I and IIx. Trends toward lower creatine kinase (CK) activity (P=0.0702) and higher surface area of type IIx fibers were observed in SCT (P=0.0925). In summary, these findings support most of the previous observations in SCT, such as 1) similar maximal power output and associated maximal oxygen consumption (VO2max) values and 2) lower exercise performances during prolonged submaximal exercise. Furthermore, performances during short supramaximal exercise were not different in SCT. Finally, the dual hemoglobinopathy condition does not seem to affect muscle characteristics.


Assuntos
Metabolismo Energético , Tolerância ao Exercício , Músculo Esquelético/enzimologia , Músculo Esquelético/fisiopatologia , Traço Falciforme/enzimologia , Traço Falciforme/fisiopatologia , Talassemia alfa/enzimologia , Talassemia alfa/fisiopatologia , Adulto , Biomarcadores/sangue , Biópsia , Camarões , Teste de Esforço , Hemoglobinas Glicadas/metabolismo , Hemoglobinas Anormais/metabolismo , Humanos , Ácido Láctico/sangue , Masculino , Força Muscular , Músculo Esquelético/patologia , Consumo de Oxigênio , Traço Falciforme/genética , Traço Falciforme/patologia , Fatores de Tempo , Adulto Jovem , Talassemia alfa/genética , Talassemia alfa/patologia
18.
Am J Physiol Heart Circ Physiol ; 298(2): H375-84, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19915173

RESUMO

The influence of sickle cell trait and/or alpha-thalassemia on skeletal muscle microvascular network characteristics was assessed and compared with control subjects [hemoglobin (Hb) AA] in 30 Cameroonian residents [10 HbAA, 5 HbAA alpha-thalassemia (alpha-t), 6 HbAS, and 9 HbASalpha-t] matched for maximal work capacity and daily energy expenditure. Subjects performed an incremental exercise to exhaustion and underwent a muscle biopsy. Muscle fiber type and surface area were not different among groups. However, sickle cell trait (SCT) was associated with lower capillary density (P < 0.05), lower capillary tortuosity (P < 0.001), and enlarged microvessels (P < 0.01). SCT carriers had reduced counts of microvessels <5-microm diameter, but a higher percentage of broader microvessels, i.e., diameter >10 microm (P < 0.05). alpha-Thalassemia seemed to be characterized by a higher capillary tortuosity and unchanged capillary density and diameter. Thus, while SCT is a priori clinically benign, we demonstrate for the first time that significant remodeling of the microvasculature occurs in SCT carriers. These modifications may possibly reflect protective adaptations against hemorheological and microcirculatory dysfunction induced by the presence of HbS. The remodeling of the microvascular network occurs to a lesser extent in alpha-thalassemia. In alpha-thalassemic subjects, increased capillary tortuosity would promote oxygen supply to muscle tissues and might compensate for the lower Hb content often reported in those subjects.


Assuntos
Capilares/patologia , Músculo Esquelético/irrigação sanguínea , Traço Falciforme/patologia , Talassemia alfa/patologia , Adulto , Capilares/fisiopatologia , Estudos de Casos e Controles , Metabolismo Energético/fisiologia , Tolerância ao Exercício/fisiologia , Humanos , Masculino , Fluxo Sanguíneo Regional/fisiologia , Traço Falciforme/fisiopatologia , Resistência Vascular/fisiologia , Avaliação da Capacidade de Trabalho , Talassemia alfa/fisiopatologia
19.
Mod Pathol ; 20(9): 914-20, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17643096

RESUMO

We report seven cases of renal medullary carcinoma collected from several institutions in Brazil. In spite of a relatively high incidence of sickle cell trait in Brazil, this is a rare tumor. All patients were males between the ages of 8 and 69 years (mean 22 years). From the collected information, the most frequent presenting symptoms were gross hematuria and flank or abdominal pain. The duration of symptoms ranged from 1 week to 5 months. Most of the tumors were poorly circumscribed arising centrally in the renal medulla. Size ranged from 4 to 12 cm (mean 7 cm) and hemorrhage and necrosis were common findings. All seven cases described showed sickled red blood cells in the tissue and six patients were confirmed to have sickle cell trait. All cases disclosed the characteristic reticular pattern consisting of tumor cell aggregates forming spaces of varied size, reminiscent of yolk sac testicular tumors of reticular type. Other findings included microcystic, tubular, trabecular, solid and adenoid-cystic patterns, rhabdoid-like cells and stromal desmoplasia. A peculiar feature was suppurative necrosis typically resembling microabscesses within epithelial aggregates. The medullary carcinoma of the 69-year-old patient was associated with a conventional clear cell carcinoma. To our knowledge, this association has not been previously reported and the patient is the oldest in the literature. The survival after diagnosis or admission ranged from 4 days to 9 months. The 8-year-old African-Brazilian patient with a circumscribed mass is alive and free of recurrence 8 years after diagnosis. This case raises the question whether a periodic search for renal medullary carcinoma in young patients who have known abnormalities of the hemoglobin gene and hematuria could result in an early diagnosis and a better survival.


Assuntos
Carcinoma Medular/patologia , Medula Renal/patologia , Neoplasias Renais/patologia , Dor Abdominal/etiologia , Adolescente , Adulto , Idoso , Brasil , Antígeno Carcinoembrionário/análise , Carcinoma Medular/química , Carcinoma Medular/complicações , Carcinoma Medular/etiologia , Carcinoma Medular/mortalidade , Carcinoma Medular/terapia , Criança , Dor no Flanco/etiologia , Hematúria/etiologia , Humanos , Imuno-Histoquímica , Queratinas/análise , Medula Renal/química , Neoplasias Renais/química , Neoplasias Renais/complicações , Neoplasias Renais/etiologia , Neoplasias Renais/mortalidade , Neoplasias Renais/terapia , Masculino , Mucina-1/análise , Metástase Neoplásica , Fatores de Risco , Traço Falciforme/complicações , Traço Falciforme/patologia , Fatores de Tempo , Resultado do Tratamento , Vimentina/análise
20.
Med Hypotheses ; 68(5): 1065-70, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17097820

RESUMO

The precise role of erythrophagocytosis in sickle cell disease is not known. Using hematological data from three studies and 791 subjects comprising of eight epidemiological groups, we found a strong statistical support for the hypothesis that erythrophagocytosis is increased in sickle cell trait, that neutrophils and lymphocytes are the most likely cells involved in erythrophagocytosis in these subjects and that increased erythrophagocytosis may for a mechanistic explanation for an increased risk of vaso-occlusive crisis in sickle cell trait. Statistically, erythrophagocytosis was not increased in subjects with homozygous sickle cell disease. Our findings offer an interesting mechanistic implication about the presence of a strong autoimmune component of sickle cell trait that can be explained by the well recognized interplay between the receptor molecule signal regulatory protein-alpha (SIRP-alpha) on the phagocyte and its ligand, CD47, on the red blood cell. Our findings also support further and closer evaluation of the other hypothesized mechanisms by which neutrophils and lymphocytes partake in differential degree of erythrophagocytosis in subjects heterozygous for the sickle hemoglobin. Finally, translation of these findings into a clinical realm suggests that the extent of erythrophagocytosis, as measured by peripheral blood hematological indicators, can serve as an important indicator of the likelihood of future vaso-occlusive crisis events in subjects of sickle cell trait.


Assuntos
Anemia Falciforme/sangue , Eritrócitos/patologia , Modelos Biológicos , Modelos Estatísticos , Fagocitose , Antígenos de Diferenciação/imunologia , Antígeno CD47/imunologia , Eritrócitos/imunologia , Homozigoto , Leucócitos/fisiologia , Ligantes , Neutrófilos/fisiologia , Receptores Imunológicos/imunologia , Traço Falciforme/genética , Traço Falciforme/patologia
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