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991.
BACKGROUND: Generalised prepubertal periodontitis is a rare entity that is usually a consequence of severe systemic diseases. Chronic granulomatous disease is one of the extremely rare inherited immunodeficiency diseases, which predisposes the patient to recurrent severe bacterial and fungal infections. AIM: The purpose of this report is to describe a 5-year old male patient suffering from prepubertal periodontitis associated with chronic granulomatous disease, who was referred to the Department of Periodontology for treatment of severe gingival inflammation. METHODS: A detailed past history was obtained and thorough clinical and laboratory examinations were performed. RESULTS: Medical tests revealed the only immunodeficiency sign as the extremely low burst test result. The patient was diagnosed as having an autosomal recessive (AR) form of chronic granulomatous disease. He was put on prophylactic treatment with trimethoprim-sulfamethoxazole (TMP-SMX) and also a periodontal maintenance regimen with regular 1-month intervals. CONCLUSION: This case report emphasises the importance of the differential diagnosis of severe immunodeficiency in the background of prepubertal periodontitis. 相似文献
992.
BACKGROUND: The aim of the present study was to investigate the level of transforming growth factor-beta 1 (TGF-beta 1) in gingival crevicular fluid (GCF) samples of cyclosporin A (CsA)-treated patients and to compare the results with control groups. METHODS: Fourteen renal transplant patients exhibiting severe CsA-induced gingival overgrowth, 10 patients with chronic gingivitis, and 10 subjects with clinically healthy periodontium were included in the study. In CsA-treated patients, GCF samples were harvested from sites exhibiting gingival overgrowth (CsA GO+) and sites not exhibiting gingival overgrowth (CsA GO-). The TGF-beta 1 levels in a total of 96 GCF samples from the 34 participants were analyzed by enzyme-linked immunosorbent assay. The results were expressed in terms of total amount (pg/2 sites) and concentration (ng/ml). RESULTS: TGF-beta 1 total amounts in CsA GO+ and CsA GO- sites were similar and significantly higher than that of healthy sites (P < 0.02 and P < 0.01, respectively). The total amount of TGF-beta 1 was also higher in gingivitis sites compared to the healthy sites, but the difference was not statistically significant (P > 0.05). CsA GO+ and CsA GO- sites exhibited higher total amount and concentration of TGF-beta 1 than that of gingivitis sites, but the differences were insignificant (P > 0.05). CONCLUSIONS: The results of the present study support the theory that CsA increases the synthesis of TGF-beta 1 in GCF. However, since the difference between CsA GO+ and CsA GO- sites was not statistically significant, it seems unlikely that GCF TGF-beta 1 level is the sole factor responsible for the CsA-induced gingival overgrowth. Complex interactions between various mediators of inflammation and tissue modeling are possibly involved in the pathogenic mechanisms of this side effect. 相似文献
993.
Flowable resin materials have been suggested as liners beneath packable composites to improve marginal integrity. This investigation evaluated the effect of low-viscosity liners on microleakage in Class II packable composite restorations. Twenty Class II cavities were prepared in extracted third molars for each of four packable composites (Heliomolar HB, Prodigy Condensable, Surefil and Tetric Condense). Ten restorations were placed for each material with their corresponding bonding agent per manufacturer's suggestion; in addition, 10 were placed with the flowable liner recommended by the manufacturer for that material. Samples were finished, stored in distilled water for at least 24 hours and thermocycled for 1,000 cycles between 5 degrees and 55 degrees C with a one-minute dwell time. Apices were sealed with epoxy cement and the teeth were varnished to within 1 mm of the margins. Samples were placed in 0.5% basic fuschin dye for 24 hours, rinsed, embedded in resin and sectioned to produce multiple sections. Microleakage was rated (0-4 ordinal scale) at both the occlusal and cervical margins. Data were analyzed with Kruskal-Wallis ANOVA for main effect and ranked sum analysis for pairwise testing (alpha = 0.05). All materials, either separately or in combination with a flowable liner, had greater leakage scores at the cervical margin compared to the occlusal margin. All packable systems tested did not yield a reduction in microleakage with the use of a flowable liner in vitro; however, the packable system with the flowable compomer used as a liner yielded significantly less overall microleakage compared to the three systems that used a resin composite liner. 相似文献
994.
The effect of hydroxyurea on rabbit subconjunctival fibroblast culture and use of hydroxyurea in rabbits after glaucoma filtration surgery. 总被引:1,自引:0,他引:1
I Yücel G Bagci Y Duranoglu A Oztürk G Aksu G Lüleci 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1999,213(5):311-319
In an in vitro study, rabbit subconjunctival fibroblasts were cultured and the effects of an antineoplastic drug, hydroxyurea (HU), on fibroblast proliferation and fibroblast attachment was investigated. The effects of HU were compared with those of mitomycin C (MMC). Different concentrations of HU and MMC were added to culture medium. The HU doses which led to 50% of inhibition (ID(50)) and the dose which led to about 90% of inhibition (subtoxic high dose, STHD) were determined to be 8 and 1,000 microg/ml, respectively. ID(50) of MMC and its STHD which led to about 100% inhibition were found to be 0.01 and 1 microg/ml, respectively. Reversibility studies revealed that inhibition disappeared depending on the dose and incubation period of both HU and MMC. In an in vivo study, glaucoma filtration surgery (GFS) was performed in rabbits which were treated with HU (treatment group) and distilled water (control group). Tissue samples were taken from the subconjunctival area treated at 1 h, 1 day, 5 days and 30 days postoperatively. The biopsy specimens were then placed in tissue culture media. Fibroblast outgrowth rates detected in the HU group were found to be significantly lower than those in the control group in the specimens taken at the end of the first hour. The difference was significant on culture days 9-15 in the biopsy specimens taken on day 1 while it was not significant in those taken on days 5 and 30. 相似文献
995.
996.
Truncated N-terminal fragments of huntingtin with expanded glutamine repeats form nuclear and cytoplasmic aggregates in cell culture 总被引:11,自引:12,他引:11
Cooper JK; Schilling G; Peters MF; Herring WJ; Sharp AH; Kaminsky Z; Masone J; Khan FA; Delanoy M; Borchelt DR; Dawson VL; Dawson TM; Ross CA 《Human molecular genetics》1998,7(5):783-790
Huntington's disease (HD) is a progressive neurodegenerative disorder
caused by an expanding CAG repeat coding for polyglutamine in the
huntingtin protein. Recent data have suggested the possibility that an
N-terminal fragment of huntingtin may aggregate in neurons of patients with
HD, both in the cytoplasm, forming dystrophic neurites, and in the nucleus,
forming intranuclear neuronal inclusion bodies. An animal model of HD using
the short N-terminal fragment of huntingtin has also been found to have
intranuclear inclusions and this same fragment can aggregate in vitro . We
have now developed a cell culture model demonstrating that N-terminal
fragments of huntingtin with expanded glutamine repeats aggregate both in
the cytoplasm and in the nucleus. Neuroblastoma cells transiently
transfected with full-length huntingtin constructs with either a normal or
expanded repeat had diffuse cytoplasmic localization of the protein. In
contrast, cells transfected with truncated N-terminal fragments showed
aggregation only if the glutamine repeat was expanded. The aggregates were
often ubiquitinated. The shorter truncated product appeared to form more
aggregates in the nucleus. Cells transfected with the expanded repeat
construct but not the normal repeat construct showed enhanced toxicity to
the apoptosis- inducing agent staurosporine. These data indicate that
N-terminal truncated fragments of huntingtin with expanded glutamine
repeats can aggregate in cells in culture and that this aggregation can be
toxic to cells. This model will be useful for future experiments to test
mechanisms of aggregation and toxicity and potentially for testing
experimental therapeutic interventions.
相似文献
997.
998.
Idiopathic CD4+ T cell lymphocytopenia with the absence of B cells and CD8+28+ cells in peripheral blood 总被引:2,自引:0,他引:2
The absence of B cells and a severe decrease in CD8+28+ cells were observed in two female children with CD4+ T cell lymphocytopenia.
Idiopathic (primary) CD4+ lymphocytopenia is a rare entity and its pathogenesis and genetics are not yet known. The literature
was reviewed, in particular for severe alterations in B and CD8+28+ cells and for the role of NF-kappa B and p56lck in the immunopathogenesis. Whether the underlying mechanism in idiopathic CD4+ lymphocytopenia is found or not, these patients
who present with severe symptoms of a combined immunodeficiency must be treated with intravenous immunoglobin regularly until
they have a compatible donor for bone marrow transplantation.
Received: 4 May 2001 / Accepted: 10 October 2002
Correspondence to N. Kutukculer 相似文献
999.
KAS Lim MF Borg M Schultz M Rice AE Potter 《Journal of Medical Imaging and Radiation Oncology》2005,49(6):516-518
Glomus tumours are uncommon neoplasms. Very rarely do they present in the paediatric age group. We describe a case of bilateral glomus tumours in a 13‐year‐old girl that were successfully treated with radiotherapy. The patient remains well 8 years after completion of treatment. 相似文献
1000.