RESUMO
BACKGROUND: BK polyomavirus-associated nephropathy (PyVAN) is an important complication after kidney transplantation. Prevalence ranges from 1% to 10%, and graft loss occurs in approximately 50% of the cases. There is no effective treatment, so early viral detection with immunosuppression tapering is the current strategy to prevent PyVAN. AIMS: To verify the frequency of PyVAN in a single center and evaluate the response to immunosuppressive adjustments through graft survival analysis. METHODS: Retrospective evaluation of a cohort of kidney transplant recipients with biopsy-proven PyVAN, compared with no-PyVAN patients regarding clinical aspects, immunosuppression, and graft survival over at least 2 years. RESULTS: There were 1404 kidney transplants analyzed in the study period, 58 with biopsy-proven PyVAN. Cumulative incidence was 4.1%. Median time from transplantation to PyVAN diagnosis was 6 (1-41) months. PyVAN was associated with recipient male gender (P = .041) and deceased donation (P = .005). Graft survival was inferior for PyVAN compared to no-PyVAN patients, 81.8% vs 75.2%, P = .019. Thirteen (22.4%) PyVAN patients lost their grafts, nine (15.5%) losses attributed to BKPyV infection. Three patients with BKPyV-associated graft losses were submitted to a successful second kidney transplant, with no evidence of viral replication during follow-up. CONCLUSION: PyVAN still is an important cause of kidney graft failure. Even though implementing active vigilance and immunosuppressive adjustment, this real-life single-center study demonstrated inferior graft survival in PyVAN patients compared to non-PyVAN.
Assuntos
Rejeição de Enxerto/virologia , Nefropatias/virologia , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/etiologia , Infecções Tumorais por Vírus/etiologia , Adulto , Vírus BK/patogenicidade , Feminino , Sobrevivência de Enxerto , Humanos , Terapia de Imunossupressão/efeitos adversos , Rim/patologia , Rim/virologia , Nefropatias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Infecções por Polyomavirus/complicações , Estudos Retrospectivos , Fatores Sexuais , Transplante Homólogo/efeitos adversos , Infecções Tumorais por Vírus/complicações , Viremia , Adulto JovemRESUMO
BACKGROUND: Kidney injury molecule-1 (KIM-1) is expressed in tubular epithelial cells after injury and may have a role in the development of renal graft fibrosis. In this study we evaluated the molecular and protein expressions of KIM-1 in dysfunctional allografts and also mRNA KIM-1 expression in urine as potential biomarkers of graft fibrosis. METHODS: Protein and mRNA levels in renal tissue and urinary sediment cells of 69 kidney transplant recipients that undertook for-cause graft biopsies were evaluated by immunohistochemistry and real-time polymerase chain reaction. The histopathology was classified according to the 2007 Banff schema. RESULTS: KIM-1 protein expression was increased in biopsies with interstitial fibrosis and tubular atrophy (IF/TA) compared with biopsies showing acute calcineurin inhibitor nephrotoxicity (CIN) (P <0.05). Kidney tissue KIM-1 mRNA signaling (in) was increased in biopsies with IF/TA compared with all other groups (P <0.05). In the urine cells KIM-1 mRNA was also increased in patients with IF/TA compared with patients with acute CIN (P <0.05). Significant correlations were found between KIM-1 protein and mRNA levels in tissue, between mRNA expressions in tissue and urine and between protein tissue expression and gene expression in the urine. CONCLUSIONS: KIM-1 seems to be a marker of kidney graft fibrosis. Urinary KIM-1 mRNA may become a useful non-invasive biomarker of the injuries that can trigger intra-graft fibrotic processes, such as interstitial fibrosis and tubular atrophy.
Assuntos
Regulação da Expressão Gênica , Rejeição de Enxerto/genética , Transplante de Rim/efeitos adversos , Túbulos Renais/patologia , Glicoproteínas de Membrana/genética , RNA Mensageiro/urina , Receptores Virais/genética , Adulto , Aloenxertos , Atrofia/patologia , Biomarcadores/análise , Biópsia por Agulha , Estudos de Coortes , Feminino , Rejeição de Enxerto/patologia , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Imuno-Histoquímica , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/patologia , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e EspecificidadeRESUMO
Malakoplakia is an unusual chronic inflammatory disease related to prior urinary tract infection. It is characterized by the presence of macrophages with foamy cytoplasm exhibiting larger PAS positive inclusions that stain for calcium and iron. Malakoplakia affects renal allograft and is associated with severe morbidity. Herein, the authors report a new case of renal graft malakoplakia in a 23-year-old female patient. The patient received a living-related donor renal transplantation with a high immunological risk. Plasmapheresis and intravenous immunoglobulin (i.v. Ig) treatment, pre- and post-transplant, and induction with rabbit anti-thymocyte globulins were used due to presence of donor specific antibodies and positive B cross match by flow cytometry. The patient had an early urinary tract infection with a good outcome. On Day 36 post-transplant (PO), the patient returned to the clinic with fever, graft pain and acute renal dysfunction leading to hemodialysis. Escherichia coli (E. coli) was present in the blood and urine culture. At the time, the renal biopsy revealed numerous sheets of macrophages with foamy, eosinophilic cytoplasm showing several PAS positive granules and large inclusions that stained strongly with hematoxylin, calcium (von Kossa method) and iron (Prussian blue). The patient was diagnosed with malakoplakia related to a kidney transplant. Despite prolonged treatment with antibiotics, determined by a susceptibility test, the patient did not recover renal function and remained on dialysis.
Assuntos
Infecções por Escherichia coli/etiologia , Transplante de Rim/efeitos adversos , Malacoplasia/etiologia , Infecções Urinárias/etiologia , Antibacterianos/uso terapêutico , Biópsia , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/terapia , Feminino , Histocompatibilidade , Humanos , Imunossupressores/efeitos adversos , Doadores Vivos , Malacoplasia/diagnóstico , Malacoplasia/terapia , Diálise Renal , Infecções Urinárias/diagnóstico , Infecções Urinárias/terapia , Adulto JovemRESUMO
Refractory celiac disease is an uncommon condition which might be associated to poor prognosis. It is often treated with immunosuppressive medications, with poor results. It is divided in type 1 and type 2, the latter carrying a high risk for lymphoma and mortality. A case of a 41 year old female patient with refractory celiac disease type 2 is reported. She was treated with oral budesonide for six months, achieving histological remission.
Assuntos
Doença Celíaca , Adulto , Budesonida , Doença Celíaca/diagnóstico , Feminino , HumanosRESUMO
Lipoprotein glomerulopathy (LPG) is an uncommon cause of nephrotic syndrome and/or kidney failure. At microscopy, LPG is characterized by the presence of lipoprotein thrombi in dilated glomerular capillaries due to different ApoE mutations. ApoE gene is located on chromosome 19q13.2, and can be identified in almost all serum lipoproteins. ApoE works as a protective factor in atherosclerosis due its interaction with receptor-mediated lipoprotein clearance and cholesterol receptor. Most common polymorphisms include ApoE2/2, ApoE3/2, ApoE3/3, ApoE4/2, ApoE4/3, and ApoE4/4. All age-groups can be affected by LPG, with a discrete male predominance. Compromised patients typically reveal dyslipidemia, type III hyperlipoproteinemia, and proteinuria. LPG treatment includes fenofibrate, antilipidemic drugs, steroids, LDL aphaeresis, plasma exchange, antiplatelet drugs, anticoagulants, urokinase, and renal transplantation. Recurrence in kidney graft suggests a pathogenic component(s) of extraglomerular humoral complex resulting from abnormal lipoprotein metabolism and presumably associated to ApoE.
Assuntos
Nefropatias/patologia , Nefropatias/terapia , Adulto , Apolipoproteínas E/genética , Pré-Escolar , Feminino , Humanos , Hipolipemiantes/uso terapêutico , Nefropatias/complicações , Nefropatias/genética , Falência Renal Crônica/etiologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Mutação , Fatores Sexuais , Resultado do TratamentoRESUMO
A case of cryptococcosis due to capsule-deficient Cryptococcus is presented, in which culturing of the clinical specimen and tests for capsular antigen in cerebrospinal fluid and serum were negative. The histopathological techniques evaluated were hematoxylin-eosin, Grocott methenamine silver, Mayers mucicarmine and Fontana-Masson. The diagnosis of cryptococcosis due to capsule-deficient Cryptococcus was confirmed by means of the Fontana-Masson technique and by direct immunofluorescence. The potential of the histochemical techniques is discussed.
Assuntos
Criptococose/patologia , Pneumopatias Fúngicas/patologia , Coloração e Rotulagem/métodos , Adulto , Feminino , HumanosRESUMO
IgG4-related disease (IgG4RD) is a recent inflammatory process of supposed autoimmune etiology, which is characterized by elevated serum IgG4 levels, dense lymphoplasmacytic infiltration rich in IgG4-positive plasma cells and storiform fibrosis. Tubulointerstitial nephritis is the most common renal manifestation, with different degrees of kidney dysfunction and variable clinical findings. Herein, the authors describe a new case of IgG4 tubulointerstitial nephritis (IgG4TN), and discuss clinic and pathologic criteria. Male patient, 72 years-old, was admitted on hospital service with clinical complaint of asthenia, loss of strength, emaciation, and anosmia. Previous history included type 2 diabetes mellitus. Laboratorial data included normochromic anemia, proteinuria, and creatinine elevation. Bilateral kidney ultrassonography/computed tomography revealed a heterogenous parenchyma, with diffuse irregular dense zones, areas of fibrosis on upper poles, and hydronephrosys. Kidney biopsy showed a dense interstitial lymphoplasmacytic infiltrate, with more than 50 plasma cell per high power field, irregular areas of fibroblastic and collagenous fibrosis, focal tubulitis, and normal glomeruli. Immunofluorescence revealed mild granular deposition of C3c and IgG in the tubular basement membrane. Immunohistochemestry was positive for CD138, lambda and Kappa light chains, and IgG4 (around forty five IgG4 positive plasma cells per high power field). IgG4 serum level was increased. The diagnosis of IgG4TN was then established. The patient received corticotherapy and strict control of glycemia with insulin, with marked improvement of symptoms and creatinine levels.
Assuntos
Imunoglobulina G , Nefrite Intersticial/diagnóstico , Nefrite Intersticial/imunologia , Idoso , Brasil , Humanos , MasculinoRESUMO
SUMMARY Refractory celiac disease is an uncommon condition which might be associated to poor prognosis. It is often treated with immunosuppressive medications, with poor results. It is divided in type 1 and type 2, the latter carrying a high risk for lymphoma and mortality. A case of a 41 year old female patient with refractory celiac disease type 2 is reported. She was treated with oral budesonide for six months, achieving histological remission.
Assuntos
Humanos , Masculino , Feminino , Doença Celíaca/diagnóstico , BudesonidaRESUMO
Neuroparacoccidiodimycosis (NPDM) is an uncommon granulomatous disease, which more frequently affects immunocompromised male patients over 30 years of age in the course of chronic lung disease. Paracoccidioides brasiliensis (PB) is an endemic fungus in Brazil, and grows as thick-walled yeast (with round to oval bodies) measuring 10 µm to 60 µm in diameter. Neuroparacoccidiodimycosi may develop many years after transmission and/or primary lung involvement. The authors describe a case of NPDM affecting a male patient, 52 years of age, farmer, heavy smoker, with clinical complaint of headache, asthenia, seizures, and prostration in the previous nine months. Upon physical examination, the patient presented regular general condition, without other relevant physical alterations. Computed tomography (CT) showed multiple bilateral pulmonary nodules associated to enlargement of the mediastinal lymph node. Magnetic resonance imaging (MRI) and CTscans of the central nervous system showed six heterogeneous nodular lesions compromising the frontal and parietal lobes, the largest one measuring 3.8 3.2 3.2 cm. The hypothesis of a neoplastic process compromising the lung and brain was considered. A biopsy of the mediastinal lymph node showed epithelioid granulomas, which exhibited round, thin-walled fungal structures in Grocott silver stain. The stereotactic biopsy of the frontal lesion was constituted by necrotic tissue admixed with some round to oval, thin-walled fungi measuring 10 µm to 60 µm, compatible with PB (identified on Grocott silver stain/confirmed in culture). The diagnosis of NPDM was then established. The employed therapeutic regimen was intravenous amphotericin B, itraconazole, and sulfamethoxazole-trimetropin. After ninety days of clinical follow-up, no episodes of seizures/neurological deficits were identified, and a marked decrease in the number and size of the lung and brain lesions were found.
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Paracoccidioidomicose/terapia , Hospedeiro Imunocomprometido , Infecções Fúngicas do Sistema Nervoso Central/cirurgia , Antifúngicos/uso terapêutico , Paracoccidioides , Paracoccidioidomicose/diagnóstico por imagem , Infecções Fúngicas do Sistema Nervoso Central/diagnóstico por imagemRESUMO
A retrospective analysis of sixteen patients with pulmonary nodules diagnosed as histoplasmoma by histopathologic evidence of Histoplasma capsulatum var capsulatum was done in an endemic area for histoplasmosis. Brazilian literature was reviewed. All patients were white, nine were men, mean age at diagnosis was 50.8 years. Six (37.5%) patients had a relevant epidemiologic story. The pulmonary nodules were 0.7-2.7 cm in diameter, presenting as granulomatous lesions with caseous necrosis. Twelve (75%) patients had solitary nodules. Histoplasmoma as a rule is a solitary nodule of up to 3 cm in an asymptomatic patient. The diagnosis is made from histopathologic evidence of the fungus, which is accomplished using a special fungus stain, Gomori-Grocott methenamine silver. Cultures or seromycology do not help the diagnosis.
Assuntos
Histoplasmose/patologia , Pneumopatias Fúngicas/patologia , Nódulo Pulmonar Solitário/patologia , Adolescente , Adulto , Idoso , Animais , Brasil , Criança , Feminino , Histoplasma/isolamento & purificação , Humanos , Pneumopatias Fúngicas/microbiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Nódulo Pulmonar Solitário/microbiologiaRESUMO
Introduction Angiosarcoma (AG) is a malignant mesenchymal neoplasm that predominantly affects the soft tissues and, to variable degrees, expresses themorphological and functional characteristics of the endothelium. The incidence of sarcomas of the central nervous system(CNS) is low (0.5% to 2.7%), and AGs involving the brain are even rarer. Case Description A 45-year-old male patient presented with complaints of headache, nausea, and vomiting. An examination showed bilateral papilledema and a right lung pleurotomy. The patient's previous history included drug addiction, pulmonary tuberculosis, lung abscess, pleural empyema, and pulmonary artery embolization for severe hemoptysis. Computed tomography/magnetic resonance imaging scans revealed a large intra-axial lesion extending into the right parietal and temporal lobes, with hemorrhagic zones. The patient underwent surgical resection of the lesion. Microscopy showed a poorly-differentiated, high-grade malignant tumor composed of plump/epithelioid cells forming small vascular spaces and solid nests, compatible with AG.In the postoperative period, the patient developed recurrent hemoptysis. A biopsy of the tissues adjacent to the pleurotomy determined the diagnosis of pulmonary AG. At 30 days after the resection, the patient died from hemoptysis, hemothorax, lung atelectasis, and intracranial hypertension related to the recurrence of the brain tumor. Conclusion Angiosarcoma is a rare neoplasia related to short survival due to the high proliferative index, which must be considered in patients presenting hemorrhagic tumors. No specific genetic abnormalities have been described for this neoplasia.
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose Pulmonar/etiologia , Anemia , Hemangiossarcoma/cirurgia , Hemangiossarcoma/complicações , Prognóstico , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias do Sistema Nervoso Central/diagnóstico , Hemangiossarcoma/fisiopatologia , Hemangiossarcoma/diagnóstico por imagem , Metástase NeoplásicaRESUMO
Abstract Lipoprotein glomerulopathy (LPG) is an uncommon cause of nephrotic syndrome and/or kidney failure. At microscopy, LPG is characterized by the presence of lipoprotein thrombi in dilated glomerular capillaries due to different ApoE mutations. ApoE gene is located on chromosome 19q13.2, and can be identified in almost all serum lipoproteins. ApoE works as a protective factor in atherosclerosis due its interaction with receptor-mediated lipoprotein clearance and cholesterol receptor. Most common polymorphisms include ApoE2/2, ApoE3/2, ApoE3/3, ApoE4/2, ApoE4/3, and ApoE4/4. All age-groups can be affected by LPG, with a discrete male predominance. Compromised patients typically reveal dyslipidemia, type III hyperlipoproteinemia, and proteinuria. LPG treatment includes fenofibrate, antilipidemic drugs, steroids, LDL aphaeresis, plasma exchange, antiplatelet drugs, anticoagulants, urokinase, and renal transplantation. Recurrence in kidney graft suggests a pathogenic component(s) of extraglomerular humoral complex resulting from abnormal lipoprotein metabolism and presumably associated to ApoE.
Resumo A glomerulopatia por lipoproteínas (GLP) é uma patologia rara que causa síndrome nefrótica e/ou insuficiência renal. Na microscopia, a GLP é caracterizada pela presença de trombos de lipoproteínas em capilares glomerulares dilatados devido a diferentes mutações no gene da ApoE. O gene da ApoE está localizado no cromossomo 19q13.2 e pode ser identificado em quase todas as lipoproteínas séricas. A ApoE age como fator de proteção na arterioesclerose por conta de sua interação com a depuração de lipoproteínas mediada por receptores e com o receptor de colesterol. Dentre os polimorfismos mais comuns destacam-se ApoE2/2, ApoE3/2, ApoE3/3, ApoE4/2, ApoE4/3 e ApoE4/4. A GLP pode acometer indivíduos de todas as faixas etárias, com discreta predominância do sexo masculino. Pacientes afetados tipicamente apresentam dislipidemia, hiperlipoproteinemia tipo III e proteinúria. O tratamento da GLP é conduzido com fenofibrato, antilipêmicos, corticosteroides, LDL-aferese, troca de plasma, antiplaquetários, anticoagulantes, uroquinase e transplante renal. Recidiva no enxerto renal indica a existência de componentes patogênicos do complexo humoral extraglomerular resultante de metabolismo lipoproteico anômalo, possivelmente associado a ApoE.
Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Adulto , Pessoa de Meia-Idade , Nefropatias/patologia , Nefropatias/terapia , Apolipoproteínas E/genética , Fatores Sexuais , Transplante de Rim , Resultado do Tratamento , Nefropatias/complicações , Nefropatias/genética , Falência Renal Crônica/cirurgia , Falência Renal Crônica/etiologia , Mutação , Hipolipemiantes/uso terapêuticoRESUMO
BACKGROUND: Gastric adenocarcinoma is more often found in men over 50 years in the form of an antral lesion. The tumor has heterogeneous histopathologic features and a poor prognosis (median survival of 15% in five years). AIM: To estimate the relationship between the presence of nodal metastasis and other prognostic factors in sporadic gastric adenocarcinoma. METHOD: Were evaluated 164 consecutive cases of gastric adenocarcinoma previously undergone gastrectomy (partial or total), without clinical evidence of distant metastasis, and determined the following variables: topography of the lesion, tumor size, Borrmann macroscopic configuration, histological grade, early or advanced lesions, Lauren histological subtype, presence of signet ring cell, degree of invasion, perigastric lymph node status, angiolymphatic/perineural invasion, and staging. RESULTS: Were found 21 early lesions (12.8%) and 143 advanced lesions (87.2%), with a predominance of lesions classified as T3 (n=99/60, 4%) and N1 (n=62/37, 8%). The nodal status was associated with depth of invasion (p<0.001) and tumor size (p<0.001). The staging was related to age (p=0.048), histological grade (p=0.003), and presence of signet ring cells (p = 0.007), angiolymphatic invasion (p = 0.001), and perineural invasion (p=0.003). CONCLUSION: In gastric cancer, lymph node involvement, tumor size and depth of invasion are histopathological data associated with the pattern of growth/tumor spread, suggesting that a wide dissection of perigastric lymph nodes is a fundamental step in the surgical treatment of these patients.
Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/secundário , Neoplasias Gástricas/patologia , Idoso , Estudos Transversais , Feminino , Humanos , Metástase Linfática , Masculino , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Carga TumoralRESUMO
Lipoprotein glomerulopathy (LPG) is a rare autosomal recessive glomerulopathy associated with the deposition of lipoprotein thrombi in the capillary lumina due to apoE gene mutations. Abnormal plasma lipoprotein profile and marked increase in serum apoliprotein E (apoE) are characteristic clinical data. The compromised patients can present nephrotic syndrome, hematuria, and progressive renal failure. Herein, the authors present the first described case of LPG in a Brazilian male patient, 11 years, who presented with a steroid-resistant nephrotic syndrome. Renal function was normal. Kidney biopsy showed markedly enlarged glomerulus, with dilated capillary loops and weak eosinophilic lipoprotein thrombi in the capillary lumina. Interstitium, tubules, arteries, and veins showed normal histologic aspect. Genotypic study for the apoE gene showed the presence of the alleles E3 and E4. The diagnosis of LPG was then performed. The patient received lipid-lowering treatment. After 2 years of follow-up, renal function is gradually decreasing, with persisting heavy proteinuria, despite a marked decrease in serum cholesterol and triglycerides levels.
Assuntos
Nefropatias/diagnóstico , Brasil , Criança , Humanos , Nefropatias/complicações , Masculino , Síndrome Nefrótica/etiologia , Doenças RarasRESUMO
INTRODUCTION: Pre-implantation kidney biopsy is a decision-making tool when considering the use of grafts from deceased donors with expanded criteria, implanting one or two kidneys and comparing this to post-transplantation biopsies. The role of histopathological alterations in kidney compartments as a prognostic factor in graft survival and function has had conflicting results. OBJECTIVE: This study evaluated the prevalence of chronic alterations in pre-implant biopsies of kidney grafts and the association of findings with graft function and survival in one year post-transplant. METHODS: 110 biopsies were analyzed between 2006 and 2009 at Santa Casa de Porto Alegre, including live donors, ideal deceased donors and those with expanded criteria. The score was computed according to criteria suggested by Remuzzi. The glomerular filtration rate (GFR) was calculated using the abbreviated MDRD formula. RESULTS: No statistical difference was found in the survival of donors stratified according to Remuzzi criteria. The GFR was significantly associated with the total scores in the groups with mild and moderate alterations, and in the kidney compartments alone, by univariate analysis. The multivariate model found an association with the presence of arteriosclerosis, glomerulosclerosis, acute rejection and delayed graft function. CONCLUSION: Pre-transplant chronic kidney alterations did not influence the post-transplantation one-year graft survival, but arteriosclerosis and glomerulosclerosis is predictive of a worse GFR. Delayed graft function and acute rejection are independent prognostic factors.
Assuntos
Sobrevivência de Enxerto , Transplante de Rim , Rim/patologia , Rim/fisiologia , Adulto , Biópsia , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos , Fatores de TempoRESUMO
ABSTRACT Despite the advances in knowledge of the neoplasm behavior, the exact understanding of the biological processes that involve the malignant tumors is not yet fully elucidated. Mechanisms such as subversion of phagocytosis, cytokines and chemokines expression, blocking of immunity and apoptosis regulation are recognized ways of tumor survival. Several of these mechanisms are also used as survival strategies of microorganisms. This article makes an analogy and compares the biological behavior of bacteria, viruses and neoplasms, showing several common points in their mechanisms of growth and survival, questioning cancer as a distinct living organism and introducing the hypothesis of synergy between viruses and bacteria in the development of neoplasms. Up to now, there are no experimental studies that effectively investigate the association between more than one microorganism as an etiologic factor of cancer.
RESUMO Apesar dos avanços no conhecimento do comportamento das neoplasias, o entendimento exato dos processos biológicos que envolvem os tumores malignos ainda não está totalmente elucidado. Mecanismos como subversão da fagocitose, expressão de citoquinas e quimiocinas, bloqueio da imunidade e regulação da apoptose são vias conhecidas de sobrevivência dos cânceres. Vários desses mecanismos também são utilizados como estratégias de sobrevivência de microrganismos. Este artigo faz uma analogia e compara o comportamento biológico das bactérias, dos vírus e das neoplasias, mostrando vários pontos em comum nos seus mecanismos de crescimento e sobrevivência, questionando o câncer como um organismo vivo distinto e introduzindo a hipótese de sinergia entre vírus e bactérias no desenvolvimento das neoplasias. Não há, até o momento, estudos experimentais que investiguem efetivamente a associação entre mais de um microrganismo como fator etiológico do câncer.
RESUMO
PURPOSE: To design an animal model of ischemia-reperfusion (I/R) in kidneys and evaluate the role that predetermined ranges of local hypothermia plays on markers of stress-oxydative as well as on histologic sections. METHODS: Twenty eight male rats Wistar, under general anesthesia, undergone right nephrectomy (G0, control group) followed by left kidney ischemia during 40 min. Four temperatures groups were designed, with seven animals randomized for each group: normothermic (G1, ±37ºC), mild hypothermia (G2, 26ºC), moderate hypothermia (G3, 15ºC) and deep hypothermia (G4, 4ºC). Left kidney temperature was assessed with an intraparenchymal probe. Left nephrectomy was performed after 240 min of reperfusion. After I/R a blood sample was obtained for f2-IP. Half of each kidney was sent to pathological evaluation and half to analyze CAT, SOD, TBARS, NO3, NO2. RESULTS: Histopathology showed that all kidneys under I/R were significantly more injured than the G0 (p<0.001). TBARS had increased levels in all I/R groups compared with the G0 (p<0.001). CAT had a significant difference (p<0.03) between G1 and G4. Finally, no difference was found on SOD, NO3, NO2 nor on f2-IP. CONCLUSION: This model of I/R was efficient to produce oxidative-stress in the kidney, showing that 4ºC offered significant decrease in free radicals production, although tissue protection was not observed.
Assuntos
Hipotermia Induzida , Isquemia/metabolismo , Rim/irrigação sanguínea , Estresse Oxidativo/fisiologia , Traumatismo por Reperfusão/metabolismo , Animais , Biomarcadores , Radicais Livres/metabolismo , Rim/metabolismo , Rim/patologia , Peroxidação de Lipídeos , Masculino , Modelos Animais , Nefrectomia , Óxido Nítrico/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , Fatores de TempoRESUMO
A 33-year old caucasian man was investigated for pain in the right flank, proteinuria, hemathuria and an elevated serum creatinine level. He also presented an abnormal ultrasonography, which revealed asymmetric kidneys. Through renal biopsy, the diagnosis of oligomeganephronia (OMN) was confirmed. OMN is a very rare form of renal hypoplasia, and late-onset in adulthood is even rarer. In the pediatric population, OMN leads to end-stage-renal-failure(ESRF) in a few years. This is the sixth case related in the literature of a late-onset OMN who have not yet developed ESRF.