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1.
Hum Pathol ; 30(11): 1328-35, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10571513

RESUMO

Basal cell carcinoma (BCC) of the skin is a locally invasive, rarely metastasizing epithelial tumor. In the current study, the expression of E-cadherin, alpha- and beta-catenin and CD44V6 in normal epidermis and on BCC cells were investigated. A significantly reduced expression of alpha-catenin and CD44V6 and a slightly reduced expression of E-cadherin on BCC cells were observed compared with the overlying epidermis. Immunoelectron microscopy was used to investigate whether the decreased expression of E-cadherin and CD44V6 was due to either an absence or downregulation of specific membrane structures or due to an overall downregulation of these adhesion molecules in all membrane structures in BCC. E-cadherin and CD44V6 were expressed in adherens junctions, desmosomes, and complex interdigitating membrane structures both in normal epidermis and in BCC. A quantitative analysis showed that only a percentage of desmosomes was stained. In addition, the effect of pro-inflammatory cytokines, such as interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), was investigated in biopsy specimens of normal skin and BCC, using a biopsy culture system and immunohistochemistry. The expression of E-cadherin and CD44V6 was not significantly decreased after culturing BCC or normal skin biopsy specimens for 48 hours with or without recombinant human (rHu)IFN-gamma or rHuTNF-alpha. It may be concluded that the decreased expression of both E-cadherin and CD44V6, observed in light microscopy, was not attributable to the absence of specific specialized structures in BCC and most likely also not caused by downregulation by local cytokines, but rather by generic downregulation of both of these adhesion molecules during malignant transformation.


Assuntos
Caderinas/biossíntese , Carcinoma Basocelular/metabolismo , Proteínas do Citoesqueleto/biossíntese , Glicoproteínas/biossíntese , Receptores de Hialuronatos/biossíntese , Neoplasias Cutâneas/metabolismo , Pele/metabolismo , Transativadores , Idoso , Caderinas/metabolismo , Células Cultivadas , Feminino , Glicoproteínas/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Imuno-Histoquímica , Junções Intercelulares/metabolismo , Masculino , Microscopia Imunoeletrônica , Pessoa de Meia-Idade , alfa Catenina , beta Catenina
2.
J Pathol ; 187(3): 351-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10398091

RESUMO

Basal cell carcinomas (BCCs) of the skin show varying degrees of peritumoural inflammatory infiltrate consisting mainly of T cells, but lack an effective T-cell-mediated immune response. This may be caused by the absence of the major histocompatibility complex (MHC) class I and II antigens, intercellular adhesion molecule-1 (ICAM-1), CD40 and CD80 (B7.1). Interferon-gamma (IFN-gamma) is known to induce or up-regulate their expression on epithelial cells, whereas interleukin-10 (IL-10) down-regulates their expression. The induction and up-regulation of HLA-ABC, HLA-DR, ICAM-1, CD40, and CD80 in BCC and normal skin from BCC patients were investigated in a culture system using recombinant human IFN-gamma (rHuIFN-gamma). The levels of IL-10 were determined in the supernatants after culture. The results showed that only ICAM-1 expression was significantly up-regulated on BCC cells. However, in the normal epidermis of BCC patients and in the epidermis overlying the tumour nests, significant up-regulation of ICAM-1, and CD40, and CD80 and slight up-regulation of HLA-DR were observed. No changes in HLA-ABC expression were observed in either normal skin or BCC. High levels of IL-10 were present in the supernatants of BCC biopsies after culture. It may be concluded that it is highly likely that the presence of IL-10 in BCC is directly or indirectly responsible for the complete lack of expression of HLA-DR, ICAM-1, CD40 and CD80 and the inconsistent expression of HLA-ABC on BCC cells in situ and may be a way of escaping immune survillance.


Assuntos
Antígenos de Neoplasias/metabolismo , Carcinoma Basocelular/imunologia , Interferon gama/farmacologia , Interleucina-10/imunologia , Neoplasias Cutâneas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno B7-1/metabolismo , Antígenos CD40/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Antígenos HLA-DR/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Técnicas Imunoenzimáticas , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Células Tumorais Cultivadas , Regulação para Cima
3.
Dermatology ; 198(1): 18-25, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10026396

RESUMO

BACKGROUND: Systemic hyalinoses are genetic generalized fibromatoses characterized by an accumulation of hyalin in the dermis. Two distinctive syndromes are recognized in the literature: infantile systemic hyalinosis (ISH) and juvenile hyaline fibromatosis (JHF). ISH and JHF are sometimes difficult to separate since they show significant overlap. OBSERVATIONS: We report on 3 children from two unrelated families suffering from JHF. The first child is severely handicapped by joint contracture, massive hyperplasia of the gingivae, diffuse skin papules and subcutaneous nodules occupying the scalp, face, perianal area, palms, soles and chest. At the same age, the second child only shows pearly skin papules on the face, groin and perianal area and gingival hyperplasia without joint stiffness or any other subjective complaint. The third patient, a brother of the second child, developed mild skin abnormalities by the end of the first year. The occurrence in siblings and consanguinity in the second family suggests autosomal recessive inheritance. Histological skin examination in the 3 cases showed hyaline deposition in the dermis and abnormal ultrastructure of fibroblasts. Biochemical findings showed mucopolysaccharide abnormalities in both families. CONCLUSION: Our patients do not only illustrate the different expressions of JHF but also show some overlap with ISH, suggesting a common cause for both disorders. Genetic studies will finally answer this question.


Assuntos
Fibromatose Gengival/patologia , Neoplasias Cutâneas/patologia , Pré-Escolar , Saúde da Família , Feminino , Fibroma/genética , Fibroma/metabolismo , Fibroma/patologia , Humanos , Hialina/metabolismo , Lactente , Artropatias/patologia , Masculino , Pele/metabolismo , Pele/patologia , Pele/ultraestrutura , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo
7.
J Med Genet ; 35(10): 841-5, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9783709

RESUMO

A large Dutch family had been known for many years to be affected with skin tumours labelled as adenoma sebaceum, which were inherited in an autosomal dominant fashion. Since this skin sign is considered pathognomonic for tuberous sclerosis complex, the condition in the family was labelled accordingly, in the absence of further clinical features of tuberous sclerosis complex-like mental retardation or epilepsy. The skin changes started at early puberty with small eruptions around the nose and progressed to larger tumours, with considerable variation in severity. Some affected members had required plastic surgical reconstruction following excision. Linkage analysis in this family was performed for the two chromosomal regions involved in tuberous sclerosis complex on chromosomes 9q34 and 16p13, but no positive linkage was found. On critical re-evaluation of the clinical and pathological data and renewed assessment, the working diagnosis was changed to autosomal dominant cylindromatosis. The recently published candidate region for cylindromatosis on chromosome 16q12-13 was subsequently proven to be positively linked with a lod score of 3.02 with marker D16S308. Review of pathological specimens confirmed the diagnosis of cylindromatosis. DNA analysis of tumour tissue showed loss of heterozygosity for the cylindromatosis CYLD1 locus. These results confirm the candidate locus for cylindromatosis on chromosome 16q12-13.


Assuntos
Adenoma/genética , Cromossomos Humanos Par 16/genética , Neoplasias Faciais/genética , Neoplasias das Glândulas Sebáceas/genética , Neoplasias Cutâneas/genética , Esclerose Tuberosa/genética , Adenoma/diagnóstico , Adenoma/patologia , Cromossomos Humanos Par 9 , Diagnóstico Diferencial , Neoplasias Faciais/diagnóstico , Neoplasias Faciais/patologia , Feminino , Ligação Genética , Haplótipos , Humanos , Perda de Heterozigosidade , Masculino , Linhagem , Neoplasias das Glândulas Sebáceas/diagnóstico , Neoplasias das Glândulas Sebáceas/patologia , Neoplasias Cutâneas/patologia , Esclerose Tuberosa/diagnóstico
9.
J Pathol ; 184(2): 169-76, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9602708

RESUMO

The peritumoural inflammatory infiltrate in basal cell carcinoma (BCC) of the skin consists mainly of T lymphocytes which hardly invade the tumour nests. The absence of intercellular adhesion molecule-1 (ICAM-1) on BCC cells may explain the lack of tumour-infiltrating cells and the lack of an active cell-mediated immune response in this tumour. In this study, the induction of ICAM-1 was investigated in BCC biopsies using recombinant human interferon-gamma (rHuIFN-gamma). The expression of interferon-gamma receptors (IFN-gamma R) in the biopsies was also investigated. The results showed that BCC cells expressed ICAM-1 after incubation with rHuIFN-gamma, but to a lesser degree than normal epidermal cells. The levels of shed ICAM-1 were significantly increased in the culture supernatants of tumour biopsies compared with those from normal skin biopsies, after culturing in the presence of rHuIFN-gamma. The expression of IFN-gamma R was significantly decreased on the tumour cells compared with the overlying epidermis. The decreased expression of IFN-gamma R on the tumour cells and the shedding of ICAM-1 into the peritumoural stroma may be a plausible mechanism by which the tumour cells are protected against an active cell-mediated immune response.


Assuntos
Carcinoma Basocelular/imunologia , Molécula 1 de Adesão Intercelular/metabolismo , Interferon gama/farmacologia , Receptores de Interferon/metabolismo , Neoplasias Cutâneas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Cultura , Feminino , Humanos , Imunidade Celular , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Proteínas Recombinantes , Pele/imunologia , Células Tumorais Cultivadas , Regulação para Cima , Receptor de Interferon gama
10.
J Thorac Cardiovasc Surg ; 113(1): 165-72, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9011686

RESUMO

Human semilunar donor heart valves can be stored in banks, awaiting transplantation. To evaluate the result of the preservation protocols, a quantitative description of the tissue is necessary. In this study we investigated in a quantitative way the contractile properties of fresh and cryopreserved porcine isolated aortic heart valve leaflets in response to a number of endogenous vasoactive compounds. The responses of strips of the aortic wall were included for comparison. Contraction was measured isometrically in response to potassium (K+; 100 mmol/L), 5-hydroxytryptamine (1 nmol/L to 100 micromol/L), noradrenaline (1 nmol/L to 100 micromol/L), endothelin-1 (0.01 nmol/L to 0.3 micromol/L), and prostaglandin F(2alpha) (0.1 nmol/L to 10 micromol/L). The pharmacologic parameters E(MAX) (the maximal response expressed as a percentage of contraction to a 100 mmol/L dose of K+) and EC50 (the concentration that produces 50% of the maximal effect) were calculated for every compound (n = 6 to 7 each). We observed that all specimens contracted in response to potassium. Its magnitude in fresh leaflets equaled 1.6 +/- 0.14 mN compared with 26.6 +/- 2.6 mN in fresh aortic wall. Noradrenaline, endothelin-1, and prostaglandin F(2alpha) all caused contraction in valvular leaflets and aortic wall, whereas 5-hydroxytryptamine caused contraction in the valvular leaflets but relaxation in aortic wall. After cryopreservation, the response to K+ amounted to 24% of the response of the fresh specimens in valvular leaflets (n = 25) and 14% in aortic wall (n = 26). The values of E(MAX) and EC50 of the responses to noradrenaline, endothelin-1, and prostaglandin F(2alpha) remained unchanged. Although the physiologic relevance of contraction of valvular leaflets needs further study, its measurement may provide an additional model to verify the consequences of alternative methods of preservation.


Assuntos
Valva Aórtica/efeitos dos fármacos , Valva Aórtica/fisiologia , Criopreservação , Animais , Dinoprosta/farmacologia , Endotelina-1/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Norepinefrina/farmacologia , Potássio/farmacologia , Serotonina/farmacologia , Suínos
11.
Thromb Haemost ; 76(3): 333-8, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8883266

RESUMO

Erythromelalgia, a characteristic aspirin-responsive microvascular thrombotic complication in essential thrombocythemia (ET), may develop despite oral anticoagulant treatment or treatment with heparin, suggesting that the generation of thrombin is not a prerequisite for its development. To study this, a cross-sectional comparison of the plasma levels of thrombomodulin (TM), platelet factor 4 (PF4), beta-thromboglobulin (beta-TG), prothrombin fragment 1 + 2 (F1 + 2) and total degradation products of fibrin(ogen) (TDP) was made between 5 ET patients suffering from erythromelalgia, 16 asymptomatic ET patients and 20 control subjects, and after treatment with aspirin, respectively. Furthermore, 2 ET patients with a history of erythromelalgia were studied at regular time intervals after discontinuation of aspirin until erythromelalgia recurred. As compared with asymptomatic ET patients and control subjects erythromelalgia was characterized by significantly higher beta-TG and TM levels but no significant differences were detected in either F1 + 2 or TDP levels. Treatment of erythromelalgia with aspirin resulted in disappearance of erythromelalgic signs and symptoms, which was paralleled by a significant decrease of beta-TG and TM levels. Histopathologic and immunohistochemical analysis of biopsies derived from erythromelalgic skin areas of 2 ET patients showed that erythromelalgic thrombi stained positively for von Willebrand factor opposed to only a weak fibrin staining. Our data suggest that erythromelalgia is caused by the intravascular activation and aggregation of platelets with subsequent sludging or occlusion of the acral arterial microvasculature. The generation of thrombin appears not to be essential for the formation of these platelet thrombi, thereby giving a plausible explanation for the inefficacy of coumadin derivatives and heparin in the prevention and treatment of erythromelalgia in essential thrombocythemia.


Assuntos
Endotélio Vascular/fisiopatologia , Eritromelalgia/sangue , Ativação Plaquetária , Trombina/biossíntese , Trombocitose/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Aspirina/uso terapêutico , Estudos Transversais , Eritromelalgia/tratamento farmacológico , Feminino , Humanos , Masculino , Microcirculação/patologia , Pessoa de Meia-Idade , Pele/irrigação sanguínea , Pele/patologia , Trombocitose/tratamento farmacológico , Trombocitose/fisiopatologia
13.
Plast Reconstr Surg ; 97(1): 86-96, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8532810

RESUMO

Microsurgeons suspect that cigarette smoking reduces the survival of free vascularized flaps and replantations, but this has never been proven. This experimental study investigates the effect of smoking on free-flap survival. A fasciocutaneous epigastric flap was used in 30 rats as a free flap and in 30 rats as a pedicled flap. Of each group, 10 rats were smoked 6 weeks before and 2 weeks after surgery, 10 rats were smoked only 6 weeks before surgery, and 10 rats underwent the sham smoking procedure. Also, a distally based dorsal skin flap was cut in all rats, representing a random vascularized flap. Vitality and size of both flaps and patency of the vascular anastomoses were assessed 14 days after surgery. The epigastric flaps were monitored by laser Doppler flowmetry and thermometry during the experiment. Survival of the free vascularized epigastric flaps was significantly lower in smoking rats. All pedicled flaps except one survived. The epigastric flaps only necrosed or survived completely, exactly correlating to the patency of the vascular anastomoses. The mean surviving area of the dorsal flaps was best for nonsmoking rats, worse for only preoperatively smoking rats, and worst for preoperatively and postoperatively smoking rats. The differences were statistically significant. Postoperative laser Doppler flow differed significantly between surviving and dying flaps, affirming the value of laser Doppler flow monitoring in microvascular surgery. In conclusion, this study proves that smoking of cigarettes is detrimental to the survival of free vascularized flaps.


Assuntos
Sobrevivência de Enxerto , Fumar/efeitos adversos , Retalhos Cirúrgicos/métodos , Anastomose Cirúrgica , Animais , Temperatura Corporal/fisiologia , Cotinina/sangue , Fluxometria por Laser-Doppler , Masculino , Nicotina/sangue , Ratos , Ratos Wistar , Fumar/fisiopatologia , Estatísticas não Paramétricas , Grau de Desobstrução Vascular/efeitos dos fármacos
14.
Anticancer Res ; 16(1): 277-82, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8615621

RESUMO

The comparative study reported here was undertaken in order to resolve the discrepancies in the detection of cytokeratin (Ck) 8 reported in previous studies. The expression of Ck 8 was compared in 6 basal cell carcinomas (BCCs) using immunohistochemical and immunoelectron microscopic techniques and a panel of 4 different commercially available monoclonal antibodies (MoAbs). The results of this comparative study demonstrated not only that the consistent expression of Ck 8 using one of the MoAbs in immunohistochemistry was confirmed by immunoelectron microscopy, but that the inconsistent expression of Ck 8 observed using two other MoAbs was also confirmed. One of the MoAbs did not show any staining at all. The inability of this MoAb to detect the expression of Ck 8 using either of the techniques also indicated that this MoAb may be directed against an epitope of Ck8 that is not detectable in BCC in situ.


Assuntos
Carcinoma Basocelular/química , Queratinas/análise , Neoplasias Cutâneas/química , Idoso , Anticorpos Monoclonais , Carcinoma Basocelular/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia Imunoeletrônica , Pessoa de Meia-Idade , Neoplasias Cutâneas/patologia
16.
J Nucl Med ; 36(4): 620-2, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7699455

RESUMO

A patient with an aorticopulmonary paraganglioma was found to have normal plasma norepinephrine and epinephrine levels and elevated dopamine levels. Iodine-123-MIBG scintigraphy did not visualize this tumor. The same finding on a negative MIBG scan in two patients with exclusively dopamine-secreting chemodectomas has been previously reported. In our patient, [111In-DTPA-D-Phe1]-octreotide scintigraphy proved to be an effective imaging technique.


Assuntos
Corpos Aórticos/diagnóstico por imagem , Dopamina/metabolismo , Radioisótopos do Iodo , Iodobenzenos , Paraganglioma Extrassuprarrenal/diagnóstico por imagem , Paraganglioma Extrassuprarrenal/metabolismo , 3-Iodobenzilguanidina , Meios de Contraste , Feminino , Humanos , Radioisótopos de Índio , Pessoa de Meia-Idade , Cintilografia , Somatostatina/análogos & derivados
17.
Anticancer Res ; 15(2): 241-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7539235

RESUMO

The expression of low molecular weight cytokeratins (Cks) 7,8,18, 18 and high molecular weight cytokeratin 10 in 23 basal cell carcinomas (BCCs) was investigated using a panel of 14 different commercially available monoclonal antibodies (MoAbs) with specific anti-cytokeratin activity. Four of these MoAbs were directed against Ck 8. The results showed that Ck 8 was detected in all 23 BCCs using MoAb 4.1.18. Two of the MoAbs showed inconsistent staining for Ck 8 and one of them did not show any staining at all. Cytokeratins 7 and 19 were detected incosistently. Cytokeratins 18 and 10 were not detected in any of the 23 BCCs that were examined. The incosistent observations on the expression of Ck 8 in BCCs in this study could have been due to different epitopes of the different cytokeratins that were detected by the different MoAbs. The results of this study lead to recommendation that whenever possible a panel of different MoAbs directed against the same Ck(s) should be used in order to minimize the risk of obtaining incorrect experimental results.


Assuntos
Carcinoma Basocelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Queratinas/biossíntese , Proteínas de Neoplasias/biossíntese , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/imunologia , Feminino , Humanos , Queratinas/análise , Queratinas/imunologia , Masculino , Pessoa de Meia-Idade , Peso Molecular , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/imunologia
18.
Br J Radiol ; 68(805): 85-8, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7881890

RESUMO

Giant oesophageal polyp (GOP) is a very rare intraluminal tumour. It is usually a benign, fibrovascular polyp arising from the proximal third of the oesophagus. We describe a patient with such a polyp but with a histological diagnosis of hamartoma. Regurgitation of the polyp into the mouth, which can lead to asphyxia, is a feared complication. A barium swallow and oesophagoscopy are the common diagnostic procedures. The site of the polyp and its volume often define the method of resection.


Assuntos
Doenças do Esôfago/complicações , Neoplasias Esofágicas/etiologia , Hamartoma/complicações , Pólipos/etiologia , Adulto , Doenças do Esôfago/diagnóstico por imagem , Doenças do Esôfago/patologia , Esôfago/diagnóstico por imagem , Esôfago/patologia , Hamartoma/diagnóstico por imagem , Hamartoma/patologia , Humanos , Masculino , Radiografia
19.
Genitourin Med ; 69(2): 102-7, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8509088

RESUMO

OBJECTIVE: To study the localisation of treponemes and to analyse the inflammatory infiltrate in biopsy specimens from patients with primary or secondary syphilis, or early infectious yaws. MATERIALS AND METHODS: Skin biopsies originating from human lesions of primary (29x) or secondary (15x) syphilis (Rotterdam), or early yaws (18x) (West Sumatra) were studied. Different histochemical and immunohistochemical detection methods were used in this study. RESULTS AND CONCLUSION: The histochemical silver staining method according to Steiner revealed the presence of T. pallidum in all cases of primary syphilis studied. In 10 out of 14 cases of secondary syphilis, treponemes were demonstrated. With an immunofluorescence staining technique (IF) using anti-T. pallidum antiserum raised in rabbits (a-Tp), T. pallidum was demonstrated in 28 out of 29 cases of primary syphilis, and in 14 out of 14 studied cases of secondary syphilis. The silver staining method and IF showed identical localisations of T. pallidum (mainly in the dermal-epidermal junction zone or throughout the dermis). Using a-Tp antiserum in the indirect immunofluorescence technique, T. pertenue could be demonstrated in the dermis more often than with Steiner silver staining. However, epidermotropism of T. pertenue in yaws specimens was remarkable, compared with more mesodermotropism of T. pallidum; numbers of T. pertenue in the dermis were limited in all specimens. The dermal inflammatory infiltrate in primary and secondary syphilis was composed mainly of lymphocytes and plasma cells. In most cases more T (CD3 positive) cells than B (CD22 positive) cells were present. Regarding T cell subpopulations, in primary syphilis, T helper/inducer (CD4 positive) cells predominated in 86% of cases. In secondary syphilitic lesions, numbers of T helper/inducer cells were less frequent than or equal to T-suppressor/cytotoxic (CD8 positive) cells in 60% of cases. Remarkably, in yaws specimens the inflammatory infiltrate consisted mainly of IgG, but also IgA and IgM producing plasma cells. T or B lymphocytes were scarce, which is in sharp contrast with findings in syphilitic lesions.


Assuntos
Pele/microbiologia , Sífilis Cutânea/microbiologia , Treponema pallidum/isolamento & purificação , Bouba/microbiologia , Adolescente , Anticorpos Antibacterianos/análise , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Coloração pela Prata , Sífilis Cutânea/imunologia , Treponema pallidum/imunologia , Bouba/imunologia
20.
J Am Coll Cardiol ; 20(7): 1465-73, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1360479

RESUMO

OBJECTIVES: The safety and long-term results of directional coronary atherectomy in stented coronary arteries were determined. In addition, tissue studies were performed to characterize the development of restenosis. METHODS: Directional coronary atherectomy was performed in restenosed stents in nine patients (10 procedures) 82 to 1,179 days after stenting. The tissue was assessed for histologic features of restenosis, smooth muscle cell phenotype, markers of cell proliferation and cell density. A control (no stenting) group consisted of 13 patients treated with directional coronary atherectomy for restenosis 14 to 597 days after coronary angioplasty, directional coronary atherectomy or laser intervention. RESULTS: Directional coronary atherectomy procedures within the stent were technically successful with results similar to those of the initial stenting procedure (2.31 +/- 0.38 vs. 2.44 +/- 0.35 mm). Of five patients with angiographic follow-up, three had restenosis requiring reintervention (surgery in two and repeat atherectomy followed by laser angioplasty in one). Intimal hyperplasia was identified in 80% of specimens after stenting and in 77% after coronary angioplasty or atherectomy. In three patients with stenting, 70% to 76% of the intimal cells showed morphologic features of a contractile phenotype by electron microscopy 47 to 185 days after coronary intervention. Evidence of ongoing proliferation (proliferating cell nuclear antigen antibody studies) was absent in all specimens studied. Although wide individual variability was present in the maximal cell density of the intimal hyperplasia, there was a trend toward a reduction in cell density over time. CONCLUSIONS: Although atherectomy is feasible for the treatment of restenosis in stented coronary arteries and initial results are excellent, recurrence of restenosis is common. Intimal hyperplasia is a nonspecific response to injury regardless of the device used and accounts for about 80% of cases of restenosis. Smooth muscle cell proliferation and phenotypic modulation toward a contractile phenotype are early events and largely completed by the time of clinical presentation of restenosis. Restenotic lesions may be predominantly cellular, matrix or a combination at a particular time after a coronary procedure.


Assuntos
Angioplastia Coronária com Balão , Aterectomia Coronária/normas , Doença das Coronárias/cirurgia , Reoperação/normas , Stents , Actinas/química , Adulto , Idoso , Aterectomia Coronária/métodos , Bélgica , Biópsia , Contagem de Células , Divisão Celular , Angiografia Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Diagnóstico por Computador , Desenho de Equipamento/normas , Estudos de Viabilidade , Feminino , França , Humanos , Hiperplasia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/química , Músculo Liso Vascular/patologia , Músculo Liso Vascular/ultraestrutura , Países Baixos , Proteínas Nucleares/química , Fenótipo , Antígeno Nuclear de Célula em Proliferação , Recidiva , Reoperação/métodos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
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