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1.
Schweiz Arch Tierheilkd ; 154(5): 199-207, 2012 May.
Artigo em Alemão | MEDLINE | ID: mdl-22547335

RESUMO

The purpose of the present study was based upon the first diagnosed bovine cutaneous leishmaniasis in a cow in Switzerland in April 2009. We continued descriptively the search for other bovine cases in Switzerland. We carried out similar investigations in the original farm where the case had occurred, and in parallel also in the neighboring farm. Additionally, veterinary practitioners sent us an overall of 12 suspected cases of bovine leishmaniasis. Following diagnostic investigations, all cases were negative for Leishmania. The occurrence of this infection appears therefore to be a very rare event. Finally some differential diagnoses are discussed.


Assuntos
Doenças dos Bovinos/epidemiologia , Leishmaniose/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Autopsia/veterinária , Biópsia/veterinária , Bovinos , Doenças dos Bovinos/diagnóstico , Diagnóstico Diferencial , Cães , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Cabras , Cavalos , Leishmania/imunologia , Leishmaniose/diagnóstico , Leishmaniose/epidemiologia , Pele/patologia , Suíça/epidemiologia
2.
Neuroscience ; 158(3): 983-94, 2009 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-18621108

RESUMO

Regulation of the extracellular matrix by proteases and protease inhibitors is a fundamental biological process for normal growth, development and repair in the CNS. Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) are the major extracellular-degrading enzymes. Two other enzyme families, a disintegrin and metalloproteinase (ADAM), and the serine proteases, plasminogen/plasminogen activator (P/PA) system, are also involved in extracellular matrix degradation. Normally, the highly integrated action of these enzyme families remodels all of the components of the matrix and performs essential functions at the cell surface involved in signaling, cell survival, and cell death. During the inflammatory response induced in infection, autoimmune reactions and hypoxia/ischemia, abnormal expression and activation of these proteases lead to breakdown of the extracellular matrix, resulting in the opening of the blood-brain barrier (BBB), preventing normal cell signaling, and eventually leading to cell death. There are several key MMPs and ADAMs that have been implicated in neuroinflammation: gelatinases A and B (MMP-2 and -9), stromelysin-1 (MMP-3), membrane-type MMP (MT1-MMP or MMP-14), and tumor necrosis factor-alpha converting enzyme (TACE). In addition, TIMP-3, which is bound to the cell surface, promotes cell death and impedes angiogenesis. Inhibitors of metalloproteinases are available, but balancing the beneficial and detrimental effects of these agents remains a challenge.


Assuntos
Barreira Hematoencefálica/enzimologia , Isquemia Encefálica/enzimologia , Encefalite/enzimologia , Matriz Extracelular/enzimologia , Metaloproteinases da Matriz/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Animais , Autoimunidade/imunologia , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/fisiopatologia , Edema Encefálico/enzimologia , Edema Encefálico/imunologia , Edema Encefálico/fisiopatologia , Isquemia Encefálica/imunologia , Isquemia Encefálica/fisiopatologia , Morte Celular/imunologia , Encefalite/imunologia , Encefalite/fisiopatologia , Humanos , Metaloproteinases da Matriz/imunologia , Degeneração Neural/enzimologia , Degeneração Neural/imunologia , Degeneração Neural/fisiopatologia , Inibidores Teciduais de Metaloproteinases/imunologia
3.
Acta Neurochir Suppl ; 105: 89-93, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19066089

RESUMO

Intracerebral hemorrhage (ICH) leads to delayed cell death in the regions around the hemorrhagic mass. Apoptosis has been identified in the dying cells, but the mechanism involved is unclear. Others and us have shown that matrix metalloproteinases (MMPs) are increased in ICH and could directly contribute to cell death. Tissue inhibitor to metalloproteinases-3 (TIMP-3) facilitates apoptosis in cancer cells and neurons by inhibiting the shedding of tumor necrosis factor-alpha (TNF-alpha) death receptors, Fas and p55TNF receptor 1, by MMP-3 and TNF-alpha converting enzyme (TACE), respectively. Therefore, TIMP-3 may contribute to cell death in ICH. We adapted the bacterial collagenase-induced hemorrhage (CIH) model to the mouse. Adult C57Bl/6 and Timp-3 knockout mice had CIH. Expression of mRNA for TIMP-3 was determined by real-time PCR. Hemorrhage volume and numbers of apoptotic cells were measured by unbiased stereology. Timp-3 mRNA was similar in the knockout and wild-type mice prior to injury and induction of CIH failed to cause an increase in Timp-3 mRNA in the wild-type. Furthermore, there were no differences found in the hemorrhage size or in the numbers of apoptotic cells between the Timp-3 knockout or wild-type. We were unable to prove the hypothesis that TIMP-3 is involved cell death in CIH in the mouse.


Assuntos
Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/metabolismo , Colagenases , Inibidor Tecidual de Metaloproteinase-3/deficiência , Animais , Apoptose/genética , Contagem de Células , Hemorragia Cerebral/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Marcação In Situ das Extremidades Cortadas , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/metabolismo , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-3/genética
4.
Cell Death Differ ; 15(1): 143-51, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17962815

RESUMO

Tissue inhibitor of metalloproteinase-3 (TIMP-3) is a natural inhibitor of metalloproteinases involved in matrix degradation and ectodomain shedding of many cell-surface proteins, including death receptors and/or their ligands. In the present study, we examined the role of TIMP-3 in Fas-mediated neuronal cell death following cerebral ischemia, using both gene deletion and pharmacological approaches. In culture, exposure of primary cortical neurons to 2 h of oxygen-glucose deprivation (OGD) resulted in delayed neuronal cell death that was dependent on activation of the death receptor, Fas. Cortical cultures derived from timp-3(-/-) mice displayed partial resistance against OGD-induced neuronal cell death and also displayed increased shedding of Fas ligand (FasL) into the culture media, compared to wild-type control cultures. Both the increased neuroprotection and increased FasL shedding in timp-3(-/-) cultures were reversed by addition of exogenous metalloproteinase inhibitors, recombinant TIMP-3 or GM6001. In vivo, timp-3(-/-) mice showed marked resistance to a brief (30 min) middle cerebral artery occlusion (MCAO), but were not protected against more severe lesions induced by 90 min of MCAO. These studies demonstrate that TIMP-3 facilitates Fas-mediated neuronal cell death following OGD and plays a pro-apoptotic role in mild cerebral ischemia.


Assuntos
Apoptose , Isquemia Encefálica/fisiopatologia , Neurônios/citologia , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Receptor fas/metabolismo , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Caspase 3/metabolismo , Hipóxia Celular , Núcleo Celular/metabolismo , Células Cultivadas , Dipeptídeos/farmacologia , Proteína Ligante Fas/metabolismo , Masculino , Metaloproteases/antagonistas & inibidores , Metaloproteases/metabolismo , Camundongos , Camundongos Mutantes , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/metabolismo , Proteínas Recombinantes/farmacologia , Inibidor Tecidual de Metaloproteinase-3/farmacologia
6.
Rev Med Chil ; 133(1): 23-32, 2005 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-15768147

RESUMO

BACKGROUND: The long-term outcome of the pure form of WHO type V lupus membranous glomerulonephritis is apparently more benign than that of other forms of lupus glomerulonephritis. However 12% of such patients progress to terminal renal failure. The presence of proteinuria may be an indication of cytotoxic agents. AIM: To study the clinical long-term outcome of WHO type V lupus membranous glomerulonephritis. MATERIAL AND METHODS: A retrospective analysis of all kidney biopsies of a University Pathology Department, with the diagnosis of WHO type V lupus membranous glomerulonephritis. Review of medical records of patients with the disease and one clinical assessment of all living patients. RESULTS: Between 1973 and 2000, 703 kidney biopsies were done to patients with systemic lupus erythematosus. Of these, 40 were membranous glomerulonephritis and in 33 patients (28 women, age range 6-71 years), data on the evolution and survival was obtained. Nineteen had type Va and the rest type Vb nephritis. Two presented with renal failure and 11 with proteinuria over 3.5 g/24 h. The median follow-up since the renal biopsy was 63 months (range 1-316). At the end of follow-up, four had a creatinine clearance of less then 15 ml/h and four a clearance between 15 and 29 ml/h (one of these received a renal allograft). Eleven (33%) patients had died, mostly due to infections. Life expectancy at five years with a creatinine clearance over 15 ml/h was 75%. Bad prognostic factors were an elevated creatinine clearance over 15 ml/h was 75%. Bad prognostic factors were an elevated creatinine and high blood pressure at the moment of the biopsy. CONCLUSIONS: The clinical outcome of these patients was bad. Twelve percent reached a stage of terminal renal failure. This is in contrast with the 3% progression to a similar stage of proliferative glomerulonephritis treated with i.v. cyclophosphamide. New therapies for this condition must be sought.


Assuntos
Glomerulonefrite Membranosa , Nefrite Lúpica , Adolescente , Adulto , Idoso , Biópsia , Criança , Chile/epidemiologia , Feminino , Seguimentos , Glomerulonefrite Membranosa/tratamento farmacológico , Glomerulonefrite Membranosa/mortalidade , Glomerulonefrite Membranosa/patologia , Humanos , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/mortalidade , Nefrite Lúpica/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
7.
Rev. méd. Chile ; 133(1): 23-32, ene. 2005. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-398013

RESUMO

Background: The long-term outcome of the pure form of WHO type V lupus membranous glomerulonephritis is apparently more benign than that of other forms of lupus glomerulonephritis. However 12percent of such patients progress to terminal renal failure. The presence of proteinuria may be an indication of cytotoxic agents. Aim: To study the clinical long-term outcome of WHO type V lupus membranous glomerulonephritis. Material and methods: A retrospective analysis of all kidney biopsies of a University Pathology Department, with the diagnosis of WHO type V lupus membranous glomerulonephritis. Review of medical records of patients with the disease and one clinical assessment of all living patients. Results: Between 1973 and 2000, 703 kidney biopsies were done to patients with systemic lupus erythematosus. Of these, 40 were membranous glomerulonephritis and in 33 patients (28 women, age range 6-71 years), data on the evolution and survival was obtained. Nineteen had type Va and the rest type Vb nephritis. Two presented with renal failure and 11 with proteinuria over 3.5 g/24h. The median follow-up since the renal biopsy was 63 months (range 1-316). At the end of follow-up, four had a creatinine clearance of less then 15 ml/h and four a clearance between 15 and 29 ml/h (one of these received a renal allograft). Eleven (33percent) patients had died, mostly due to infections. Life expectancy at five years with a creatinine clearance over 15 ml/h was 75percent. Bad prognostic factors were an elevated creatinine clearance over 15 ml/h was 75percent. Bad prognostic factors were an elevated creatinine and high blood pressure at the moment of the biopsy. Conclusions: The clinical outcome of these patients was bad. Twelve percent reached a stage of terminal renal failure. This is in contrast with the 3percent progression to a similar stage of proliferative glomerulonephritis treated with i.v. cyclophosphamide. New therapies for this condition must be sought.


Assuntos
Adolescente , Adulto , Masculino , Humanos , Feminino , Criança , Pessoa de Meia-Idade , Glomerulonefrite Membranosa/mortalidade , Glomerulonefrite Membranosa/patologia , Glomerulonefrite Membranosa/tratamento farmacológico , Nefrite Lúpica/mortalidade , Nefrite Lúpica/patologia , Nefrite Lúpica/tratamento farmacológico , Biópsia , Chile/epidemiologia , Seguimentos
8.
Apoptosis ; 9(5): 649-56, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15314293

RESUMO

Cell surface death receptor-mediated neuronal apoptosis, which is a critical component of neurodegeneration, is modulated by matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Doxorubicin (Dox) induces neuronal death by the activation of death receptor pathways. Recently, we demonstrated that Dox-induced neuronal apoptosis is regulated by the balance of MMP-3 and TIMP-3 in rat cortical cultures. Inbred mouse strains exhibit differential susceptibility to cell death stimuli in vivo. Prior to employing transgenic approaches to further investigate the roles of TIMP-3 and MMP-3 in neuronal death, we examined whether inbred mice display strain-dependent vulnerability to Dox. We induced neuronal apoptosis with Dox in primary neuronal cultures established from cerebral cortices of embryonic day 15 C57BL/10 or C57BL/6 mice. Using fluorescence activated cell sorting for neurons, we found that C57BL/6 cortical cultures exhibit a 28% greater neuronal death following Dox treatment than C57BL/10. Real-time PCR of unstimulated cultures revealed that C57BL/10 cortical cultures have reduced basal mRNA levels encoding the pro-apoptotic proteins: Fas, FasL, and TIMP-3, but increased levels of the anti-apoptotic molecule MMP-3 as compared to C57BL/6. Furthermore, C57BL/10 cultures treated with Dox displayed an enhanced induction of mRNA transcripts that encode anti-apoptotic MMPs. These results show that C57BL/10 cortical cultures are more resistant to death receptor-mediated apoptotic cell death as compared to C57BL/6, and suggest that this difference is related to Fas, FasL, and MMP expression. Strain-dependent differences in response to apoptotic stimuli may be an important consideration for developing transgenic models of neurodegeneration.


Assuntos
Apoptose/efeitos dos fármacos , Córtex Cerebral/fisiologia , Doxorrubicina/farmacologia , Glicoproteínas de Membrana/metabolismo , Neurônios/citologia , RNA Mensageiro/genética , Receptor fas/metabolismo , Animais , Células Cultivadas , Córtex Cerebral/embriologia , Proteína Ligante Fas , Citometria de Fluxo , Glicoproteínas de Membrana/genética , Metaloproteases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie , Receptor fas/genética
9.
Rev. méd. Chile ; 132(6): 742-746, jun. 2004. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-384223

RESUMO

Acute interstitial nephritis is a mononuclear and sterile inflammation of the renal interstice caused by drugs, infections or immune phenomena. The clinical presentation is characterized by the triad of rash, fever and eosinophilia. We report a 32 years old man, in treatment with lamotrigine for depression, admitted to the hospital due to fever, abdominal pain, jaundice, cutaneus rash and malaise. Due to an oliguric renal failure of acute onset, a renal biopsy was done. The pathological study showed a granulomatous acute interstitial nephritis. He was started on hemodialysis and treated with cessation of the drug and corticosteroids, with complete recovery of the renal function (Rev Méd Chile 2004; 132: 742-6).


Assuntos
Humanos , Masculino , Adulto , Antidepressivos/efeitos adversos , Nefrite Intersticial/induzido quimicamente , Nefrite Intersticial/patologia , Doença Aguda , Rim/ultraestrutura
10.
Eur J Neurosci ; 18(5): 1050-60, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12956705

RESUMO

Metalloproteinase activity at the cell surface influences cellular sensitivity to extrinsic death vs. survival signals in a variety of cell types, through proteolytic shedding of cell surface signalling molecules. Tissue inhibitor of metalloproteinases-3 (TIMP-3) is a unique natural metalloproteinase inhibitor that plays a pro-apoptotic role through its ability to inhibit metalloproteinases that proteolytically cleave death receptors and their ligands from the cell surface. To study the convergence of metalloproteinase activity and death receptor signalling in neurons, we established an in vitro model of neuronal apoptosis utilizing the chemotherapeutic drug, doxorubicin (Dox). Primary cultures established from embryonic rat cerebral cortices displayed robust and selective neuronal apoptosis in response to Dox, an effect that was dependent on the activation of the death receptor, Fas. We demonstrate that both TIMP-3 and matrix metalloproteinase-3 (MMP-3) are constitutively expressed by primary cortical neurons in culture, and selectively modulated Fas-mediated neuronal apoptosis induced by Dox. Metalloproteinase inhibition by TIMP-3 was found to be necessary for Dox-induced neuronal death, whereas addition of active MMP-3 markedly attenuated apoptosis and diminished Fas-Fas ligand interaction at the cell surface. These observations implicate a physiological role for the balance of TIMP-3 and MMP-3 activity at the neuronal surface in regulating death receptor sensitivity. The convergence of metalloproteinase activity and death receptor signalling at the cell surface may influence neuronal cell death vs. survival decisions.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Doxorrubicina/farmacologia , Metaloproteinase 3 da Matriz/metabolismo , Neurônios/efeitos dos fármacos , Fenilalanina/análogos & derivados , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Animais , Antígenos CD/metabolismo , Western Blotting , Caspase 3 , Caspases/metabolismo , Contagem de Células , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Embrião de Mamíferos , Proteína Glial Fibrilar Ácida/metabolismo , Imunoglobulina G/farmacologia , Imuno-Histoquímica , Indóis/metabolismo , L-Lactato Desidrogenase/metabolismo , Metaloproteinase 3 da Matriz/imunologia , Neurônios/fisiologia , Fenilalanina/farmacologia , Fosfopiruvato Hidratase/metabolismo , Testes de Precipitina/métodos , RNA Mensageiro/biossíntese , Ratos , Ratos Endogâmicos WKY , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Tiofenos/farmacologia , Fatores de Tempo , Receptor fas/farmacologia
11.
Stroke ; 32(5): 1162-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11340226

RESUMO

BACKGROUND AND PURPOSE: Vascular disease causes multi-infarct dementia (MID) or Binswanger's disease (BD), the latter of which is a progressive form of vascular dementia (VaD) associated pathologically with fibrinoid and hyaline changes in brain arterioles with injury to the white matter. Clinically, BD patients have long-standing hypertension with disturbances of gait and intellect. Because matrix metalloproteinases (MMPs) are important in cerebral infarction, we hypothesized that disturbances in the MMPs may be involved in VAD: METHODS: Brain tissues from 5 patients with VaD of the BD or multi-infarct type (MID) were immunostained with antibodies to glial fibrillary acidic protein (GFAP), a microglial/macrophage cell marker (PG-M1), gelatinase A (MMP-2), stromelysin-1 (MMP-3), and gelatinase B (MMP-9). Control tissues were from 8 elderly patients: 4 with strokes without dementia and 4 without neurological diseases. RESULTS: PG-M1+ cells appeared around infarcts in patients with strokes without dementia and in patients with VAD: In 2 of the 3 BD patients, PG-M1 cells were prominent near damaged arterioles and scattered diffusely in white matter. MMP-2 was seen normally in perivascular macrophages and in astrocytic processes near blood vessels and was present in patients with strokes in reactive astrocytes. MMP-9 was rarely seen. MMP-3 was seen in PG-M1+ microglial/macrophage cells around the acute infarctions. In BD, MMP-3 persisted in tissue macrophages and disappeared in long-standing white matter gliosis. CONCLUSIONS: These observations suggest that MMPs may participate in the damage to the white matter associated with VAD: Microglia/macrophage-induced damage, which is amenable to treatment, may be a factor in the progressive forms of VAD:


Assuntos
Demência Vascular/metabolismo , Demência Vascular/patologia , Metaloproteinases da Matriz/metabolismo , Fibras Nervosas Mielinizadas/enzimologia , Fibras Nervosas Mielinizadas/patologia , Idoso , Antígenos de Diferenciação/metabolismo , Astrócitos/metabolismo , Astrócitos/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Infarto Cerebral/complicações , Infarto Cerebral/metabolismo , Infarto Cerebral/patologia , Demência Vascular/complicações , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Progressão da Doença , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/metabolismo , Gliose/patologia , Humanos , Imuno-Histoquímica , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Microglia/metabolismo , Microglia/patologia , Pessoa de Meia-Idade
12.
Urology ; 58(1): 105, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11445495

RESUMO

We report a case of a verrucous carcinoma of the renal pelvis after a long history of a renal pelvis stone. Only 1 case of verrucous carcinoma of the renal pelvis has been previously reported, and ours is the first case not associated with a horseshoe kidney.


Assuntos
Carcinoma Verrucoso/etiologia , Cálculos Renais/complicações , Neoplasias Renais/etiologia , Carcinoma Verrucoso/diagnóstico , Carcinoma Verrucoso/cirurgia , Feminino , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/cirurgia , Pelve Renal , Pessoa de Meia-Idade
13.
Ann Thorac Surg ; 71(3 Suppl): S150-5; discussion S183-4, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11265851

RESUMO

BACKGROUND: Two modifications of the surgical implantation protocol for the Penn State Total Artificial Heart (ETAH) were evaluated: Phrenic nerve ischemia was prevented by minimizing dissection and traction; and hemostasis was augmented and ETAH cuff anastomoses reinforced by using fibrin glue. METHODS: Thirteen Holstein calves underwent orthotopic surgical implantation of the Penn State ETAH between February 1998 and August 2000. Mean hemodynamic and laboratory chemistry variables from the first postoperative week were compared between calves receiving the original (n = 7) and modified (n = 6) protocol. RESULTS: Calves assigned to the modified protocol displayed an improvement in the Po2/FiO2 ratio compared to original (419.4 +/- 17.5 vs 336.3 +/- 35.4, respectively; p = 0.05). All additional parameters were equivalent between groups. The percent survival of animals receiving the modified protocol at 2, 4, and 12 weeks was higher than that of animals that underwent the original protocol. Original-protocol calf deaths consisting of hemothorax (n = 3), and respiratory failure (n = 1) were prevented in the modified protocol. CONCLUSIONS: Our results suggest that manipulations in surgical protocol may promote increased survival in calves implanted with the Penn State ETAH.


Assuntos
Coração Artificial , Implantação de Prótese/métodos , Animais , Bovinos , Causas de Morte , Coração Artificial/efeitos adversos , Hemodinâmica , Complicações Pós-Operatórias/epidemiologia , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Taxa de Sobrevida
14.
Ann Thorac Surg ; 71(3 Suppl): S156-61; discussion S183-4, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11265852

RESUMO

Management of patients with end-stage cardiac disease remains a vexing problem. Limitations in medical management and a fixed supply of donor organs for cardiac transplant have a continued impact on this growing population of patients. Mechanical circulatory support has proved very successful as a means of bridging patients to cardiac transplant when all medical options have been exhausted. The development of a chronic system of circulatory support has been underway at the Pennsylvania State University for nearly 30 years. These efforts have been recently merged with the industrial partnership with Arrow International toward the development of the LionHeart LVD-2000 (Arrow International, Reading, PA) completely implanted left ventricular support system. We present an overview of the system, details of implantation, a review of preclinical studies, and a synopsis of the first European implants. Early results have demonstrated the system to be safe, effective, and reliable. Transcutaneous energy transmission and the compliance chamber have been validated.


Assuntos
Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Animais , Desenho de Equipamento , Humanos , Implantação de Prótese/métodos , Fatores de Tempo
15.
Brain Res ; 893(1-2): 104-12, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11222998

RESUMO

Reperfusion damages the blood-brain barrier (BBB). Matrix metalloproteinases (MMPs) are associated with the opening of the BBB, but their cellular localization and activation mechanisms are uncertain. We used immunohistochemistry to determine the cellular localization of the MMPs in reperfused rat brain, and cell cultures to study their activation. Spontaneously hypertensive rats (SHR) had a 90 min middle cerebral artery occlusion (MCAO) followed by reperfusion for times from 3 h to 21 days. Frozen sections were immunostained with antibodies to gelatinase A (MMP-2), stromelysin-1 (MMP-3), and gelatinase B (MMP-9). Sham-operated control rats showed MMP-2 immunostaining in astrocytic processes next to blood vessels. After 3 h of the onset of reperfusion MMP-2 immunostaining increased in astrocytes. At 24 h immunoreactivity for MMP-3 and MMP-9 appeared. MMP-3 co-localized with activated microglia (Ox-42+) and ischemic neurons (NeuN+). MMP-9 immunostaining was seen at 48 h in endothelial cells, neutrophils, and neurons. At 5 and 21 days intense MMP-2 staining was seen in reactive astrocytes around the ischemic core. Studies of activation of the MMP were done in lipopolysaccharide (LPS)-stimulated astrocyte and microglia cultures. Stimulated astrocytes produced an activated form of MMP-2. When microglia were stimulated, they activated MMP-9. Immunostaining showed MMP-3 in cultures of enriched microglial cells. The hydroxymate-type, MMP inhibitor, BB-1101, blocked the activation of MMP-2 and MMP-9 by LPS in mixed glial cultures. We propose that MMP-2 is normally present in astrocytic end feet, and that during ischemia MMP-9 and MMP-3 are produced. MMP-3 in microglia/macrophages may be activating proMMP-9. Our results show that a differential expression of MMPs by astrocytes, microglia, and endothelial cells at the blood vessels is involved in the proteolytic disruption of the BBB.


Assuntos
Antígenos CD , Antígenos de Neoplasias , Antígenos de Superfície , Proteínas Aviárias , Proteínas Sanguíneas , Isquemia Encefálica/enzimologia , Encéfalo/metabolismo , Metaloproteinases da Matriz/metabolismo , Microglia/enzimologia , Traumatismo por Reperfusão/enzimologia , Animais , Basigina , Barreira Hematoencefálica/fisiologia , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Isquemia Encefálica/patologia , Células Cultivadas , Ativação Enzimática/fisiologia , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Glicoproteínas de Membrana/metabolismo , Microglia/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia
16.
Sci Total Environ ; 280(1-3): 17-37, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11763265

RESUMO

PCBs and other persistent organochlorine (OC) pesticides were analyzed in sediment cores collected from six lakes in Yukon Territory and one in northern British Columbia, Canada, with the objective of establishing sources and historical trends of these contaminants. DDT was found to be the most prominent OC in the sediment profiles of most of the lakes. Maximum sigmaDDT levels (3.47-2680 ng g(-1) dw) were observed in sediment slices dated to the 1950s from lakes near populated areas. In contrast, in more remote lakes (Hanson, Kusawa and Lindeman), the maximum sigmaDDT concentrations were observed in the sediments dated to the 1970s. Highest sigmaPCB and sigmaDDT concentrations were measured in sediments from Watson Lake, near a suspected PCB waste disposal site and in a region where DDT was heavily applied in the 1950s and 1960s. Elevated sigmaPCB concentrations [16.1-93.6 ng g(-1) dry weight (dw)] were also observed in sediments from lakes situated near populated areas, relative to Kusawa and Lindeman (11.1 and 12.7 ng g(-1) dw, respectively). Recent sigmaPCB fluxes ranged from 621 ng m(-2) y(-1) in Kusawa Lake to 16400 ng m(-2) y(-1) in Little Atlin Lake. The extremely high sedimentation rate (2050 g m(-2) y(-1)) in glacial fed Lindeman Lake gave rise to elevated fluxes of sigmaPCB (2410 ng m(-2) y(-1)) and other OCs, despite much lower concentrations in the sediment. Levels of hexachlorocyclohexanes (sigmaHCH), chlordane-related compounds (sigmaCHL), and chlorobenzenes (sigmaCBz) were in the low ng g(-1) (dw) range in all lake sediments, similar to concentrations previously reported for Arctic lakes in Canada, indicating that their major source was long range atmospheric transport. Contamination of the lakes with PCBs and DDT near populated areas of the Yukon Territory appears to be a result of regional activities rather than long range transport and deposition. The results also point to glacial runoff as a significant source of OCs to small, high elevation lakes (Lindeman), but not to larger lakes within the Yukon River drainage basin that are also affected by glacial sources (Kusawa, Laberge).


Assuntos
Poluentes Ambientais/análise , Sedimentos Geológicos/química , Inseticidas/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Gelo , Movimentos da Água , Yukon
17.
Plast Reconstr Surg ; 106(3): 721-5; discussion 726-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10987484

RESUMO

The temporary tarsorrhaphy suture is introduced as a simple effective technique to prevent scleral show or ectropion secondary to laser skin resurfacing or laser blepharoplasty. In all but severe cases of prior existing scleral show or ectropion, the temporary tarsorrhaphy suture has been completely effective. It is also successfully used to prevent scleral show and ectropion for patients with poor lid snap and loss of elasticity of the lower eyelid at the time of laser skin resurfacing and blepharoplasty. A 5-0 Prolene suture is placed through the gray line to approximate the upper and lower eyelids and is left in place for 5 days. This supports the lower eyelid during the critical period of dermal and epidermal regeneration and during the formation of new collagen and elastin.


Assuntos
Blefaroplastia/efeitos adversos , Ectrópio/prevenção & controle , Pálpebras/cirurgia , Terapia a Laser/efeitos adversos , Ritidoplastia/efeitos adversos , Técnicas de Sutura , Idoso , Ectrópio/etiologia , Feminino , Humanos , Esclera
18.
Foot Ankle Int ; 21(7): 596-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10919628

RESUMO

Osteoid osteomas of the foot and ankle are relatively rare and notoriously difficult to diagnose. Juxta-articular osteoid osteomas are more difficult to treat and often have a significant delay in diagnosis. We report a case of a juxta-articular osteoid osteoma of the tibial plafond. Once the diagnosis was made, excisional biopsy was performed percutaneously under computed tomography (CT) guidance as an outpatient in the radiology suite. The patient had complete resolution of symptoms and remains pain free at two years follow-up. CT guided resection can be a lower morbidity and more cost effective technique to treat this lesion than traditional methods.


Assuntos
Neoplasias Ósseas/cirurgia , Osteoma Osteoide/cirurgia , Tíbia/cirurgia , Tomografia Computadorizada por Raios X , Biópsia por Agulha/métodos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoma Osteoide/diagnóstico por imagem , Osteoma Osteoide/patologia , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tomografia Computadorizada por Raios X/métodos
20.
Artif Organs ; 24(5): 362-72, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10848677

RESUMO

The number of pediatric patients requiring some form of mechanical circulatory assistance is growing throughout the world because of new surgical procedures and the success of pediatric cardiac transplantation. However, the salvage rate for those patients requiring circulatory support may be as low as 25%. Despite the fact that Penn State's 70 cc pneumatic ventricular assist device has been used with a success rate of over 90% in more than 250 patients worldwide, efforts to scale down the pump have encountered difficulties. Animal experiments with a 15 cc version were unsuccessful, with explanted pumps showing extensive thrombus deposition within the pumping chamber. The materials used to fabricate the smaller pump as well as the basic operating principles are identical to the successful adult-sized version. It is therefore believed that reducing the size of the pump altered the internal flow field, and that fluid dynamic factors were responsible for the high degree of thrombus observed with the implanted devices. A dimensional analysis was conducted that revealed significant differences in both Reynolds (Re) and Strouhal (St) numbers between the successful and unsuccessful pumps. Two component laser Doppler velocimetry was then used to characterize the internal flow field quantitatively. Comparison with data from the 70 cc pump showed a reduction in wall shear stress and turbulence levels in the 15 cc pump that would yield an environment conducive to clot formation.


Assuntos
Coração Auxiliar , Hemorreologia , Adulto , Conversão Análogo-Digital , Animais , Materiais Biocompatíveis , Criança , Desenho de Equipamento , Transplante de Coração , Humanos , Fluxometria por Laser-Doppler , Reologia , Processamento de Sinais Assistido por Computador , Estresse Mecânico , Propriedades de Superfície , Procedimentos Cirúrgicos Operatórios , Trombose/etiologia
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