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1.
Summary Sarcoidosis is a multisystem disease characterized by enhanced immune responses at sites of involvement. To elucidate the immunopathogenesis of ophthalmic lesions, cell infiltrates in biopsies from conjunctiva and other tissues involved (lungs, lymph nodes, skin) were studied in 26 patients with active sarcoidosis in order to define the surface phenotype and the distribution of cells in granulomatous lesions. Biopsy specimens were also stained for detection of immunoglobulins, complement and fibrinogen deposits. The data demonstrate a lymphocytes/macrophages interaction in the central core of granulomatous areas as the crucial event that initiates the maintains the state of inflammation: at all sites of disease activity is present a compartmentalization of T-cells expressing a helper-related phenotype which account for the great majority of infiltrating cells both in the early lesions (aggregate of macrophages surrounded by lymphocytic infiltrate) and in well-organized sarcoid granulomata. The presence of plasma cells and immunoglobulin deposits may represent an epiphenomenon in line with the helper infiltration, suggesting a local hyper-reactivity of the B-cells immune system. This study suggests some immunopathogenetic mechanisms leading to the formation and growth of conjunctival sarcoid granulomata.  相似文献   
2.
To further define the mechanisms responsible for the alpha-interferon (alpha-IFN) efficacy in the treatment of hairy cell leukemia (HCL), experiments were carried out to specify the cytotoxic events taking place following this type of therapy. Although an increased natural killer (NK) activity was demonstrable after alpha-IFN treatment, evidence has been provided that hairy cells were not specifically lysed either by fresh autologous/allogenic NK lymphocytes or by lymphokine activated killer (LAK) cells. This property could not be induced in vitro by alpha-IFN or by interleukin-2 (IL-2). Our data favour the hypothesis that the increase of NK cell activity observed following alpha-IFN therapy has not a direct antineoplastic effect but is likely to be of relevance for a non-specific enhancement of the host immune system. In alpha-IFN treated HCL this latter property may account for the better resistance to infections which usually represents the major cause of mortality in these patients.  相似文献   
3.
Giant cavernous hemangiomas: Diagnosis and surgical strategies   总被引:4,自引:0,他引:4  
From January, 1972 to June, 1989, 51 patients with liver hemangiomas (32 females and 19 males, mean age 35 years) were evaluated for surgical treatment. Diameters of the masses were 5 cm to 20 cm (median 8.5 cm). Nine of the patients had already been treated for cancer. Twenty-two (43.1%) of the 51 patients were symptomatic and 29 (56.9%) patients were asymptomatic. In 34 patients (66.7%) a definite diagnosis of hemangioma was made by scintiscan and/or ultrasound and/or computed tomography and/or angiography while in the remaining 17 (33.3%) patients the diagnosis was uncertain. The most common indications for resection were the presence of a symptomatic angioma, a symptomatic mass with an uncertain diagnosis, and/or lack of a definite pre-operative diagnosis. Surgery was performed on 25 patients. Ten anatomic and 15 atypical resections or enucleations were performed. There were no postoperative deaths. Two further patients, operated for probable hemangioma, were found to have primary hepatic malignancies. In the 26 unresected patients, no complications were observed during follow-up. In 3 patients, hemangioma enlargement was detected by ultrasound, but there were no symptoms. As cavernous liver hemangiomas are now more reliably diagnosed and their natural history is usually uneventful, surgery can be avoided in most cases. However, when a non-resection policy is adopted, an exact diagnosis is essential in order to rule out primary or metastatic cancer. Surgical exploration and treatment should be limited to symptomatic or complicated cases as well as to patients with an uncertain diagnosis.
Resumen Cincuenta y un pacientes con hemangiomas del higado (32 mujeres y 19 hombres, edad promedio 35 años) fueron valorados en cuanto a tratamiento quirúrgico en el período enero 1972 a junio de 1989; el diámetro de las lesiones oscilo entre 5 y 20 cm (promedio 8.5 cm). Nueve de los pacientes ya habían sido tratados por cáncer; 22/51 (43.1%) estaban sintomáticos y 29/51 (56.9%) eran asintomáticos. En 34/51 (66.7%) se hizo el diagnóstico definitivo de hemangioma mediante escintigrafia y/o ultrasonido y/o tomografía computadorizada y/o angiografia, en tanto que en los otros 17 pacientes (33.3%) el diagnóstico resultó incierto. Las indicaciones más comunes para resección fueron: presencia de un angioma sintomático, una masa asintomática con diagnóstico incierto y/o ausencia de diagnóstico preoperatorio definitivo. Se practicó cirugía en 25/51 pacientes, habiéndose realizado 10 resecciones anatómicas y 15 resecciones atípicas o enucleaciones. No hubo muertes postoperatorias. Otros dos pacientes operados por probable hemangioma demostraron tener neoplasias malignas hepáticas primarias. En los 26 pacientes no resecados no se observaron complicaciones durante el seguimiento; en tres casos se detectó ensanche del hemangioma en el examen con ultrasonido, pero no se presentaron síntomas. Puesto que actualmente los hemangiomas cavernosos del hígado pueden ser diagnosticados con mayor certeza y puesto que su historia natural generalmente está libre de complicaciones es posible evitar la cirugía en la mayoría de los casos. Sin embargo, cuando se pretenda adoptar una política de no resección es esencial establecer el diagnóstico exacto para excluir la posibilidad de un cáncer primario o metastásico. La exploración y el tratamiento quirúrgicos debe permanecer limitados a los hemangiomas sintomáticos o complicados, y en ningún caso deben significar riesgo para el paciente.

Résumé De Janvier 1972 à Juin 1989, 51 patients ayant un hémangiome du foie (32 femmes et 19 hommes, âge moyen 35 ans) ont été examinés en vue d'une exérèse chirurgicale. Le diamètre de la lésion variait entre 5 et 20 cm (médiane = 8.5 cm). Neuf des patients avaient déjà été traités pour un cancer; 22/51 (43.1%) étaient symptomatiques alors que 29/51 (56.9%) étaient asymptomatiques. Chez 34/51 patients (66.7%), le diagnostic définitif d'hémangiome a été confirmé par scintigraphie et/ou échographie et/ou tomodensitométrie, alors que chez les 17 autres (33.3%), le diagnostic était uncertain. Les indications d'une résection les plus fréquentes étaient: la présence d'un angiome symptomatique, une masse symptomatique avec un diagnostic uncertain, et/ou absence de diagnostic définitif préopératoire. Vingt-cinq des 51 patients ont été opérés. Il y a eu 10 résections anatomiques et 15 résections atypiques ou énucléations. Il n'y a pas eu de mortalité postopératoire. Deux autres patients, traités pour ce que l'on soupçonnait être une probalbe hémangiome du foie, avaient en fait un cancer hépatique. Chez les 26 patients non résequés, il n'y avait pas eu de complication. Chez trois patients, on a mis en évidence une augmentation de volume par l'échographie, mais ces modifications ne s'accompagnait d'aucune symptomatologie. Comme on peut faire le diagnostic d'hémangiome carverneux du foie avec plus de fiabilité qu'avant, et comme on sait que leur histoire naturelle est généralement bénigne, on peut le plus souvent surseoir à l'exérèse chirurgicale. Cependant, il importe de toujours faire le diagnositc avec certitude, de façon à éliminer un cancer primitif ou sécondaire du foie.
  相似文献   
4.
In the current study, we investigated the cytotoxic ability of peripheral blood mononuclear cells (PBMC) recovered from patients with acute nonlymphoblastic leukemia (ANLL) in complete remission (CR) against natural killer (NK)-sensitive, NK-resistant, autologous and allogeneic leukemic target cells taken at diagnosis. Our purpose was to define the role played by cytotoxic mechanisms in the control of leukemic cell growth in ANLL. Experiments were carried out at resting conditions and after in vitro activation with recombinant interleukin-2 (rIL-2) and anti-CD3 monoclonal antibody (moAb). At resting conditions, PBMC recovered from ANLL patients displayed a NK function that was not significantly different from controls (mean +/- standard error of the mean [SEM]: 21.9% +/- 3.9% versus control values of 27.5% +/- 2.9%; the P value was not significant [NS]), but they were unable to show cytotoxic activity against autologous and allogeneic leukemic cells. After in vitro boosting with rIL-2, PBMC were able to generate lymphokine activated killer (LAK) cells, as demonstrated by an increased killing of NK-resistant Daudi targets (16.3% +/- 2.7%). Although LAK activity was quantitatively lower than in control subjects (mean +/- SEM: 16.3% +/- 2.7% versus control values of 79.8% +/- 3.1%; P less than 0.001), it still exerted a cytotoxic effect against autologous and allogeneic leukemic cells. Similar results were obtained when anti-CD3 moAb was used as a stimulus in vitro. Our data suggest that nonspecific cytotoxic cells may be triggered to exert an in vitro cytotoxic effect on leukemic cells, which could possibly play a key role in vivo in the control of leukemic cell growth regulation.  相似文献   
5.
Transglutaminase (TGase) activity was reduced in intact mitogen-stimulated human peripheral blood lymphocytes (PBL) when compared to intact resting PBL. Moreover, a treatment of the same quiescent immunocompetent cells with purified liver TGase and Ca2+ completely suppressed the mitogen-induced blast transformation. A decrease in TGase activity in neoplastically transformed seminal vesicle epithelial cells with respect to their normal parent counterpart was also observed. Our data support the notion of a possible implication of TGase in cell proliferation and transformation.  相似文献   
6.
We studied superoxide anion (O2) generation by alveolar macrophages (AM) isolated from bronchoalveolar lavages (BAL) of patients with sarcoidosis, and assayed immediately after the isolation or after maintenance in culture for 2 days. In assays of cells freshly isolated from BAL, AM of patients with active sarcoidosis with a high-intensity lymphocytic alveolitis produced more O2- in response to phorbol myristate acetate than AM of patients with inactive sarcoidosis. Also, after 2 days of cultivation sarcoid AM were heterogeneous in their capability to metabolize oxygen, although both AM of active and inactive sarcoid patients produced higher amounts of O2- than AM of healthy subjects. In vitro treatment with recombinant interferon-gamma (rIFN-gamma) caused an enhancement of the capability of AM of inactive sarcoid patients to produce O2- in response to PMA. AM of patients with active sarcoidosis did not respond to rIFN-gamma when they already produced O2- vigorously. However, they became sensitive to the activating effect of rIFN-gamma after the down-modulation of their capability to produce O2-, that occurred upon prolonged cultivation. Monocytes isolated from blood of sarcoid patients and assayed immediately or after different times of cultivation did not produce more O2- than control monocytes and monocyte-derived macrophages, thus indicating that the activation of AM in sarcoidosis is likely a local phenomenon. These studies strengthen the notion that T lymphocyte-macrophage interaction is a critical event in the pathogenesis of sarcoidosis and establish that the enhanced capability to metabolize oxygen to highly reactive intermediates by AM is one of the consequence of this interaction.  相似文献   
7.
In this study we investigated the serum levels of a released soluble form of the interleukin-2 receptor (sIL-2R) in 42 patients with rheumatoid arthritis and in 12 cases of systemic lupus erythematosus. Data were evaluated in relationship to the clinical phase and compared with those observed in normal controls (N=56) and in osteoarthritis (N = 7). Increased levels were observed in both rheumatoid arthritis (mean ± SE, 604±49 U/ml) and systemic lupus erythematosus (1438±481 U/ml). These values were significantly higher than in control (256±15 U/ml;P<0.001) and in osteoarthritis (298±33 U/ml;P<0.001) groups. In addition, the highest values were associated with the active phases of both rheumatoid arthritis (active vs inactive, 771±78 vs 451±39 U/ml;P<0.001) and systemic lupus erythematosus (active vs inactive, 2108±489 vs 499±75 U/ml;P<0.001). Our findings suggest that the detection of sIL-2R in rheumatoid arthritis and in systemic lupus erythematosus may represent a good marker of disease activity, which indirectly indicates the ongoing activation and/or proliferation of immunoreactive cells which are involved in the pathogenetic events of these autoimmune conditions.  相似文献   
8.
9.
PURPOSE: The aim of this study was to compare the value of endoluminal ultrasonography (ELUS) with magnetic resonance imaging (MRI) for preoperative staging of rectal carcinoma. METHODS: Thirty-seven consecutive patients were examined by ELUS and MRI. Imaging results were compared with pathohistologic studies. A tumor extending beyond the bowel wall was considered to be positive and one within the bowel wall was considered negative. Lymph node involvement was considered present if nodes equal to or greater than 5 mm in diameter were found in the perirectal tissue. For evaluating the differences between the two methods, the Mc Nemar test was performed. RESULTS: T-Staging was correct in 88.2 percent (30/34) of patients by ELUS and in 82.3 percent (28/34) by MRI (difference not significant). N-Staging was correct in 80 percent (20/25) by ELUS and in 60 percent (15/25) by MRI (difference of borderline significance). A comprehensive preoperative staging (T + N) was made correctly in 68 percent (17/25) by ELUS and in 48 percent only (12/25) by MRI (difference not significant). CONCLUSIONS: We suggest that ELUS and MRI must be evaluated within the framework of established parameters when treatment modalities such as preoperative radiation therapy and local or radical surgical approach must be decided.  相似文献   
10.
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