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11.
Synovial fluids from patients with rheumatoid arthritis (13 cases), ankylosing spondylitis (six), psoriatic arthritis (two), osteoarthritis (three) and rubella arthritis (four) contain interleukin-1 (Il-1) activity as measured in the CH3/He mouse thymocyte assay. That this activity is Il-1 was shown by: (i) the time course of thymocyte stimulation; (ii) failure of PHA blast cells to absorb out the activity; (iii) molecular weight of 15,000-20,000 daltons, and (iv) ability to stimulate prostaglandin E2 production from synovial cells. These results indicate that IL-1 is an important mediator in the inflammatory pathway of different types of joint disease.  相似文献   
12.
The discovery of nucleated erythrocytes in maternal circulationprovides a potential source for non-invasive prenatal diagnosis.We have evaluated the use of a three-stage procedure to determinethe number of cells that are of fetal rather than maternal origin.First, monoclonal antibodies specific for CD45 and CD14 wereused in conjunction with a magnetic (MACS) column to depleteunwanted leukocytes from maternal blood. This was followed bya positive MACS enrichment for nucleated erythrocytes, usingan anti-CD71 (transferrin receptor) monoclonal antibody. Todiscriminate between fetal nucleated erythrocytes and thoseof maternal origin, enriched fractions were simultaneously stainedwith an anti-fetal haemoglobin (HbF) antibody and hybridizedwith probes specific for X and Y chromosomes. Samples were thensubjected to blind analysis along with negative control samplesfrom non-pregnant volunteers. Using this dual analysis, we wereable to determine that less than one nucleated erythrocyte perml of maternal blood was of fetal origin. Small numbers of thesefetal cells were found in 87.5% of pregnancies, ranging from6 to 35 weeks gestational age. Comparison of HbF and X/Y probedata also suggests that the fetal cells are less suitable forfluorescence in-situ hybridization (FISH) analysis than similarpreparations from other sources. cell separation methods/fluorescence in-situ hybridization/hereditary diseases/polymerase chain reaction/pregnancy  相似文献   
13.
In this study the intensity of expression of major histocompatibility complex (MHC) class I and II antigens, adhesion molecule i.e. ICAM-1, epidermal growth factor receptor i.e. EGFr, T cell marker and cytokeratin were compared in oral squamous cell carcinoma (OSCC) and in the benign ameloblastoma of the jaws. The results showed that: a) There was strong expression of both monomorphic and of polymorphic class I MHC antigens (90% of cases) in both basal and suprabasal cells of controls from normal mucose. b) Whereas up to 4% of OSCCs and 27% of ameloblastomas showed complete loss of monomorphic class I antigens, the frequency of polymorphic class I abnormalities was even more marked in both tumour types. c) Strong expression of class II MHC antigens and of ECFr was observed in the basal cells of most normal controls. d) Both class II (50% of cases) and ICAM-1 (30% of cases) showed strong expression in OSCC but not in ameloblastoma. The statistical values between OSCC and normal basal cells for class II and ICAM-1 were not significant whilst the corresponding values for OSCC compared with ameloblastoma were p<0.001 and p<0.001. In the case of OSCC, there were a large number of infiltrating T cells expressing activation marker i.e. class II antigen. e) Strong expression of EGFr was seen in more than 90% of the OSCC cases compared with only 16% of ameloblastomas (0.01

0.001). Our working hypothesis to explain these abnormalities is that although both tumour types (more so in the case of ameloblastoma) have in place an escape mechanism from the immune system, the overexpression of EGFr in OSCC may in part be responsible for the more aggressive behaviour of the malignancy compared with the locally invasive but benign ameloblastoma.  相似文献   

14.
A chemically induced syngeneic hamster tumour model of human oral squamous cell carcinoma (OSCC) was used to investigate the possible influence of locally transplanted growing rumours on the immune system of the recipient. Cell activation and cell cytotoxicity assays were performed in vitro using the colorimetric MTT assay to measure any possible changes. The fast growing nature of the tumour model if grafted locally as a fragment was confirmed but not if injected as a single cell suspension (SCS). Stimulation (Concanavalin A) of spleen cells from normal and from tumour bearing animals showed that there was a minor though statistically significant decrease in the mitogenic response of the latter. Thus, the respective stimulatory indices (SI) were 4.06+/-1.61 and 2.06+/-0.87 (0.02

0.01). No significant difference was observed when spleen cells were stimulated with interleukin-2 (IL-2), although there was a similar trend. Pre-immunisation of animals with irradiated autologous SCS three weeks prior to grafting, resulted in a significant decrease in the tumour growth rate of subsequently grafted tumour. Thus, the mean If: SD (weight of takes in mg) for the successful takes of untreated (n=10) and treated (n=9) groups were 52.0+/-52.2 and 25.7+/-19.4 (0.02

0.05) respectively. The number of cases with no tumour takes were 2 of 10 (20%) and 6 of 9 (66%) respectively. In a separate experiment groups of 5 animals were immunized with an increasing number of cells as irradiated SCS, the results of which demonstrated an inverse correlation between the rate of tumour growth and the number of injected tumour cells. The addition of irradiated SCS to IL-2 activated normal spleen cells (LAK cells) in vitro led to a dose-related decrease in the efficiency of cytotoxicity of latter when tested against an xenogeneic super-sensitive surrogate tumour target cell line (Fen cells). Thus, the percent killing by IL-2-activated normal spleen cells was 56.4%. The corresponding mean values for IL-2 activated normal spleen cells in the presence of tumour SCS at 25/1 and 50/1 ratios were 35.9% (p<0.05) and 11.9% (p<0.001) respectively. Ln an attempt to establish the presence of T suppressor cells, spleen cells from tumour bearing animals were injected concomitantly with SCS into 5 recipients. After four weeks no tumour growth had occurred. In conclusion we demonstrated that the presence of injected or grafted tumour had only a minor effect on systemic immune function but induced a strong local anergic effect. This local anergic effect was demonstrable as blocking of LAK activity and thus perhaps allowed suppression of the functional activities of incoming immunocompetent cells.  相似文献   

15.
The authors report a series of 68 cases of renal cancer observed over a 9-year period. Patients consisted of 33 women (49%) and 35 men (51%), with a mean age of 53 years (range: 23-85 years). The clinical features were polymorphic, dominated by loin pain (44%), haematuria (37%), a lumbar mass (19%), alteration of the general state (7%). The diagnosis was established by ultrasonography in 59 patients and CT-scan in 63 patients. The mean tumour diameter was 11 cm (4-22 cm) and two cases presented bilateral tumours. The time to diagnosis ranged from 1 month to 7 years. Staging reflected the advanced stage of the cancer. Treatment was surgical for 58 patients (58%). A lumbar incision was performed, in 40% of cases. Radical nephrectomy was performed in 82%, and partial nephrectomy was performed in 3% of patients. Histological examination of the specimen showed renal cell carcinoma in 75% of cases. The lymph nodes removed were invaded in 20% of cases. The mean follow-up was 29 months (6 to 84 months), normal at one year for 44 patients (86%) and at 5 years for 16 patients (31%). Tumour recurrence in the renal compartment was observed in 2 patients (4%). Asynchronous metastases occurred in 11 patients (21.5%) after 21 months. (range: 12-48 months). The overall 5-year survival was 100% T1, 69% T2 and 50% T3.  相似文献   
16.
Placement alkaline phosphatase (PLAP) is one of the cellular phosphatases (ALP) expressed in patients with testis cancers, particularly in seminomas. Using various techniques including Western blot and high-performance liquid chromatography (HPLC) systems and ATC2, a newly developed specific anti-PLAP monoclonal antibody (Mab), the presence of active form of PLAP in lysates prepared from testis tumour fragment and tumour cell lines, was studied. This was carried out following isolation of PLAP from biological samples using CNBr Sepharose-conjugated ATC2 beads. The results showed that: (1) The target for the newly developed Mab ATC2 was PLAP. (2) The ATC2-conjugated bead system was an efficient method for isolating pure PLAP. (3) Diethylamine (DEA), in contrast to urea and glycine, was the most efficient for separation of PLAP from ATC2-conjugated beads, as the isolated molecule did not lose any phosphatase activity and there was very little uncoupling of the ATC2 Mab from the beads. (4) ATC2-conjugated CNBr beads could pick up PLAP from a solution containing standard PLAP and lysates prepared from tumour cell lines or testis tissue fragments positive for the PLAP. (5) HPLC profile of testis tumour lines and testis tumours showed two distinct peaks with ALP activity, one at retention time 7-8 min (corresponding to 95 kDa molecule) and one at 12-13 min corresponding to 70 kDa molecule). These data demonstrated the potential use of various biochemical methods in combination with HPLC for isolation of the fully functional molecules with ALP activity from different samples including lysates prepared from patients with testis cancer. The nature of ALP activity at 95 kDa is being investigated as no such molecule has been reported previously. These techniques might have an important implication for an early detection of germ cell tumours, particularly in patients with equivocal ultrasound.  相似文献   
17.
18.
Langerhans cell histiocytose is a rare condition in childhood. It presents in different ways ranging from a single bony disease to a multisystemic disease involving vital organs. CASE REPORT: We report a case of single bone involvement revealed by torticollis in an eight-year-old boy. The diagnosis was evocated on radiological findings and confirmed by histologic aspects. After a period of 2,5 years, this child is in total spontaneous remission. CONCLUSION: Torticollis must be explored and watched. Eosinophilic granuloma can be a rare aetiology in children. The outcome is often favorable.  相似文献   
19.
The use of laser to treat cutaneous lesions began with Dr. Leon Goldman and his coworkers in 1963. Ten years later, these authors described promising effects on angiomas using the continuous-wave neodymium:yttrium–aluminum–garnet laser. In 1983, Anderson et al. proposed the photothermolysis theory. The selective destruction of vascular lesions is based on this principle, and it is still a guide for treatment of vascular lesions. Over the past 25 years, laser treatment of cutaneous vascular lesions has progressed significantly. Vascular lasers such as argon, tunable dye, krypton, and copper vapor were used in the past and were associated not only with risk of scarring but also hyper- and hypopigmentation. Since then, new devices were developed in order to minimize these side effects. This article presents an overview and update of the current available treatment of cutaneous vascular lesions and covers future directions for vascular laser technology.  相似文献   
20.
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