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1.
Chronically Trypanosoma cruzi infected "I" rats and syngeneic naive recipients, transferred with a T cell enriched spleen cell population from infected donors, develop an attenuated arthritis when challenged with complete Freund's adjuvant. We report that cyclophosphamide, 40 mg/kg body weight, given 48 h before induction, was able to reestablish or exacerbate adjuvant arthritis in infected and control rats, respectively. Although the T cell enriched spleen cells from infected donors continued to down regulate adjuvant arthritis in syngeneic recipients given cyclophosphamide 48 h before cell transfer, treatment of infected donors with cyclophosphamide, 48 h before cell collection, prevented these cells from exerting such effect when transferred to healthy recipients receiving no cyclophosphamide. It is suggested that cyclophosphamide may primarily affect a suppressor cell population, present in the infected host, with regulatory activity on adjuvant arthritis.  相似文献   
2.
Immunoblot assays showed that mycobacterial fibronectin-binding antigens are important targets of the humoral immune response in tuberculosis and leprosy. Using culture filtrate antigens of Mycobacterium tuberculosis, strong reactivity with the fibronectin-binding of 30-31 kD (Fn 30-31) was demonstrated in 55.9% of tuberculosis sera and in 56.5% of lepromatous leprosy sera. Sera from patients with tuberculoid leprosy and control sera gave very weak binding. Reactivity of tuberculosis and lepromatous leprosy sera with the fibronectin-binding antigen of 58-60 kD (Fn 58-60) was less conspicuous. The ability to react with fibronectin of the antigens of 58-60 and 30-31 kD was demonstrated by parallel labelling with a fibronectin-biotin conjugate. Fn 30-31 was purified to homogeneity by a two-step procedure and used for ELISA. Positive titres were found in 63% out of 65 tuberculosis sera and in 60.5% out of 43 lepromatous leprosy sera. Antibody titres in lepromatous leprosy sera were higher than in tuberculosis sera. Our observations indicate indirectly that M. leprae possess a highly immunogenic molecule homologous to M. tuberculosis Fn 30-31, which elicits a high antibody response in lepromatous leprosy but not in tuberculoid leprosy. In this investigation, direct evidence for the presence of this antigen in M. leprae was obtained by immunochemistry of lepromatous leprosy lesions with a monospecific antibody raised against M. tuberculosis Fn 30-31.  相似文献   
3.
It has previously been shown that, in the heterozygous state, mutations in the SOX9 gene cause campomelic dysplasia (CD) and the often associated autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one recurrent mutation were characterized in one SOX9 allele each, and in one case, no mutation was found. Four missense mutations are all located within the high mobility group (HMG) domain. They either reduce or abolish the DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense and three frameshift mutations identified, two leave the C-terminal transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or almost completely intact. When tested in cell transfection experiments, the recurrent nonsense mutation Y440X, found in two patients who survived for four and more than 9 years, respectively, exhibits some residual transactivation ability. In contrast, a frameshift mutation extending the protein by 70 residues at codon 507, found in a patient who died shortly after birth, showed no transactivation. This is apparently due to instability of the mutant SOX9 protein as demonstrated by Western blotting. Amino acid substitutions and nonsense mutations are found in patients with and without XY sex reversal, indicating that sex reversal in CD is subject to variable penetrance. Finally, none of 18 female patients with XY gonadal dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP assays, providing evidence that SOX9 mutations do not usually result in XY sex reversal without skeletal malformations.   相似文献   
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Thromboembolic phenomena have been described in patients with thalassaemia intermedia and major, although there are relatively few epidemiological data on the overall frequency of these complications. To obtain more insight into the risk and mechanism of venous thromboembolism in thalassaemia, the aims of this study were: (i) to establish retrospectively the prevalence of thromboembolic events in a large group of adults with thalassaemia intermedia and major during a follow up period of 10 years; (ii) to measure in subgroups of these patients sensitive markers of activation of coagulation and fibrinolysis enzymes; and (iii) to look for possible procoagulant mechanisms. A high prevalence of thromboembolic events was found, particularly in splenectomized patients with thalassaemia intermedia (29%). These patients had high plasma levels of markers of coagulation and fibrinolysis activation. Furthermore, thalassaemic red cells and erythroid precursors from splenectomized patients with thalassaemia intermedia had an enhanced capacity to generate thrombin. To evaluate the role of splenectomy per se on procoagulant activity, we evaluated the capacity to form thrombin in healthy individuals who had been splenectomized for trauma. They produced the same amount of thrombin as non-splenectomized controls. In conclusion, the results of this study show the existence of a hypercoagulable state in splenectomized patients with thalassaemia intermedia and that their red and erythroid cells are capable of acting as activated platelets in thrombin generation.  相似文献   
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Clinical Rheumatology - Evidence for Chagas disease reactivation (CDR) in rheumatologic patients under rheumatologic treatments (RTs) is scarce. To screen and follow-up patients with rheumatic...  相似文献   
8.
Zusammenfassung In dieser Arbeit wurden die Gebisse von 31 männlichen und 45 weiblichen Dysgnathieträgern mit Hilfe des Berliner Meßsystems vermessen und die Ergebnisse mit Hilfe eines Computers ausgewertet. Es erfolgt der Vergleich der Parameter zwischen Probanden mit Progenie, Kreuzbiß, offenem Biß und Schmalkiefer. Die Veränderung der Werte wurden longitudinal in den Hauptentwicklungsstufen Milchgebiß, Wechselgebiß und im bleibenden Gebiß untersucht. Dabei werden auch nach der Behandlung noch zwischen den Anomaliegruppen bei einzelnen Werten signifikante Unterschiede gefunden.
Summary In this study dental plaster casts of 31 male and 45 female subjects were measured using the Berlin measurement system and evaluated with the aid of a computer. The parameters of subjects with class III malocclusion, crossbite, open bite and class II/1 malocclusion were compared. The changes were studied longitudinally in the main developmental stages, namely the deciduous, mixed and permanent dentitions. Significant differences were found also following treatment between the malocclusion groups.

Résumé On a mesuré les dentures de 31 hommes et 45 femmes présentant des dysgnathies à l'aide du système de mesure mis au point à Berlin; les valeurs ainsi établies on fait l'objet d'un traitement sur ordinateur. On a procédé à la comparaison des paramètres des sujets atteints de prognathie inférieure, occlusion croisée, béance et endognathie. On a étudié la modification des valeurs de manière longitudinale, en suivant les principales étapes d'évolution: denture lactéale, denture mixte et denture permanente. L'examen a permis, même après le traitement, d'établir, pour chacune des valeurs, des différences importantes d'un groupe d'anomalie à l'autre.
  相似文献   
9.
Ameloblastoma is a benign odontogenic tumor of epithelial origin. It is locally aggressive with unlimited growth capacity and has a high potential for malignant transformation as well as metastasis. Ameloblastoma has no established preventive measures although majority of patients are between ages 30 and 60 years. Molecular and genetic factors that promote oncogenic transformation of odontogenic epithelium to ameloblastoma are strongly linked to dysregulation of multiple genes associated with mitogen‐activated protein kinase, sonic hedgehog, and WNT/β‐catenin signaling pathways. Treatment of ameloblastoma is focused on surgical resection with a wide margin of normal tissue because of its high propensity for locoregional invasion; but this is often associated with significant patient morbidity. The relatively high recurrence rate of ameloblastoma is influenced by the type of molecular etiological factors, the management approach, and how early the patient presents for treatment. It is expected that further elucidation of molecular factors that orchestrate pathogenesis and recurrence of ameloblastoma will lead to new diagnostic markers and targeted drug therapies for ameloblastoma.  相似文献   
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