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41.

Purpose

Spondyloenchondrodysplasia is a rare immuno-osseous dysplasia caused by biallelic mutations in ACP5. We aimed to provide a survey of the skeletal, neurological and immune manifestations of this disease in a cohort of molecularly confirmed cases.

Methods

We compiled clinical, genetic and serological data from a total of 26 patients from 18 pedigrees, all with biallelic ACP5 mutations.

Results

We observed a variability in skeletal, neurological and immune phenotypes, which was sometimes marked even between affected siblings. In total, 22 of 26 patients manifested autoimmune disease, most frequently autoimmune thrombocytopenia and systemic lupus erythematosus. Four patients were considered to demonstrate no clinical autoimmune disease, although two were positive for autoantibodies. In the majority of patients tested we detected upregulated expression of interferon-stimulated genes (ISGs), in keeping with the autoimmune phenotype and the likely immune-regulatory function of the deficient protein tartrate resistant acid phosphatase (TRAP). Two mutation positive patients did not demonstrate an upregulation of ISGs, including one patient with significant autoimmune disease controlled by immunosuppressive therapy.

Conclusions

Our data expand the known phenotype of SPENCD. We propose that the OMIM differentiation between spondyloenchondrodysplasia and spondyloenchondrodysplasia with immune dysregulation is no longer appropriate, since the molecular evidence that we provide suggests that these phenotypes represent a continuum of the same disorder. In addition, the absence of an interferon signature following immunomodulatory treatments in a patient with significant autoimmune disease may indicate a therapeutic response important for the immune manifestations of spondyloenchondrodysplasia.
  相似文献   
42.
Hairy cell leukemia (HCL) is a chronic B-cell lymphoproliferative disorder with pathological manifestations usually including splenomegaly and panctopenia. Interferons (IFNs), specifically of the α subtypes have shown a significant anti-tumor effect in HCL patients, with improvement of hematological parameters within the first few months of treatment. However, the therapeutic effect of IFN-α is still rather limited. The mechanisms responsible for the beneficial action of IFN-α in HCL patients are unclear. A continuous line of cells (Eskol) from a patient diagnosed with HCL was established and shown to have several properties of HCL. Even though, Eskol cells are very resistant to anti-proliferative activity of IFN-α, Daudi cells, another human B-cell-derived cell line, are very sensitive to anti-proliferative activity of IFN-α and are commonly used as a model cell to test anti-proliferative effect of IFN-α. To understand the molecular reason(s) behind the observed obvious differences to IFN sensitivity of above cells, we have analyzed the expression levels of BCL2, caspase-1, Laminin and PARP in these cells. We found that Daudi cells do not express BCL2 at all, and probably because of that, these cells have constantly cleaved, and probably activated form of caspase-1. However, when we overexpresed BCL2 in these cells, they lost processed form of caspase-1 and became resistant to anti-proliferative activity of IFN-α. These results let us to suggest that IFN-α sensitivity of B-cell lymphomas, once again, depends on the presence or absence of BCL2.  相似文献   
43.
Methylmalonic acidemia (MMA) is an inherited organic acidemia usually present with recurrent episodes of acute illness. A typical episode is ushered in with ketonuria and vomiting, followed by acidosis, dehydration, and lethargy, leading, in the absence of aggressive treatment, to coma and death. We report an infant with MMA presented with diabetes symptoms. A 13-month-old girl complained of polydipsia, diuresis, and loss of weight. She had clinical signs of diabetic ketoacidosis such as dehydration, deep sighing respiration, smell of ketones, lethargy, and vomiting. Laboratory analysis showed hyperglycemia with acidosis and ketonuria. She was treated with parenteral fluid, electrolyte, and insulin infusion. Two days after her discharge, after having a meal rich in protein, she was brought unconscious with hepatomegaly, severe acidosis, ketonuria, and mild hyperammonemia. The absence of hyperglycemia and the presence of neurologic findings suggested organic acidemia. MMA was diagnosed because of methylmalonic aciduria and elevated C3 carnitine esters. Cranial magnetic resonance imaging (MRI) showed increased uptake of radiocontrast material in the basal ganglia bilaterally. A homozygous mutation in exon 4 of the MMAA gene was found in mutation analysis and confirmed the diagnosis of cblA-deficient MMA. Neurologic regression was improved with treatment of low-protein diet, vitamin B12, and l-carnitine. In patients born to consanguineous parents who admit during infancy with severe acidosis refractory to treatment, organic acidemias should be kept in mind, even they have high blood glucose. The definitive diagnosis is important because it may allow a specific treatment and a favorable evolution to prevent the sequelae.  相似文献   
44.
The objectives of this study were to determine whether type-2 diabetes was associated with a higher bone mineral density (BMD) in men and women and to evaluate the differences in mineral metabolism between diabetic and normal subjects by using biochemical bone turnover markers. In this study, 52 patients (37 females/15 males) aged 41-64 with type-2 diabetes mellitus and 48 nondiabetic control subjects (34 females/14 males) were evaluated. In men, BMD was significantly higher in diabetics at the forearm (p <0.05), whereas in women tended to be higher at the hip (p=0.002). Serum osteocalcin (p<0.0001), bone alkaline phosphatase (BAP) (p<0.05) and carboxyterminal telopeptide (CTx) (p<0.05) were higher in the control group than in diabetics. In men, serum osteocalcin (p<0.05) and CTx (p<0.005) and, in women, serum osteocalcin (p<0.0001) and BAP (p<0.05) were lower in diabetic subjects. In conclusion, our findings suggest that although bone formation is decreased in type-2 diabetes, diabetic patients are not susceptible to bone resorption. This low bone turnover can slow the rate of bone loss and cause a higher bone density than expected for their age.  相似文献   
45.
Yavuz O  Cam M  Bukan N  Guven A  Silan F 《Acta histochemica》2003,105(3):261-266
The aim of the present study was the evaluation of possible protective effects of melatonin against beta-cell damage in streptozotocin-induced diabetes in rats. Malondialdehyde levels and glutathione peroxidase activity were measured in pancreatic homogenates. Pancreatic beta-cells were examined by immunohistochemical methods. Streptozotocin was injected intraperitoneally at a single dose of 60 mg/kg for induction of diabetes. Melatonin (200 microg/kg/day, ip) was injected for 3 days prior to administration of streptozotocin; these injections were continued until the end of the study (4 weeks). Streptozotocin induced a significant increase in malondialdehyde levels (p < 0.01) and a significant decrease in glutathione peroxidase activity (p < 0.05) in pancreatic tissue. Degeneration of islet cells and weak immunohistochemical staining of insulin was observed in diabetic rats. Treatment of diabetic rats with melatonin markedly reduced malondialdehyde production (p < 0.05) and increased glutathione peroxidase activity (p < 0.01) without affecting hyperglycemia. Increased staining of insulin and preservation of islet cells were apparent in the melatonin-treated diabetic rats. These data suggest that melatonin treatment has a therapeutic effect in diabetes by reduction of oxidative stress and preservation of pancreatic beta-cell integrity.  相似文献   
46.
Small plaque parapsoriasis (SPP) is one of the cutaneous T-cell lymphoproliferative disorders. The aim of the present study was to show the antigenic profile of a subset of dendritic cells and lymphocytes in SPP in comparison with normal cells to provide data on the role of these two cell types in the pathogenesis of SPP. Skin biopsy specimens of lesions were obtained from 8 patients with SPP. Biopsies of the healthy skin from 9 control individuals were also analyzed. Immunohistochemistry was performed on the frozen tissue sections to reveal binding of anti-HLA Class II, anti-CD1a, anti-CD4, anti-CD8, anti-CD44, anti-CD45, and anti-CD68 monoclonal antibodies. There was a statistically significant increase in the number of CD1a(+), Langerhans cells (LCs), HLA-DR-immunoreactive and, CD1a-positive dermal dendritic cells and CD68(+) macrophages in the SPP group (p=0.008, 0.008, 0.002 and <0.0009, respectively). The number of lymphocytes positive for CD4, CD8 and CD45 was significantly higher than normal in the SPP group (p=0.015, <0.0009 and <0.0009, respectively). Our study demonstrates that both peptide- and lipid-based antigens are involved in the persistent antigenic exposure in SPP. Dendritic cells play a pivotal role in SPP by presenting antigens by both LC and dermal dendritic cells via MHC Class II and CD1a molecules. The CD68(+) macrophages are thought to be involved in the immune response in this pathology as an antigen-presenting cell.  相似文献   
47.
Gol M  Akan P  Dogan E  Karas C  Saygili U  Posaci C 《Maturitas》2006,53(3):252-259
OBJECTIVES: To investigate the effects of conjugated equine estrogen (CEE), CEE plus medroxyprogesterone acetate (MPA), CEE plus Nomegestrol acetate (NA), and raloxifene on serum high sensitivity C-reactive protein (hs-CRP) and homocysteine (Hcy) levels in healthy postmenopausal women. MATERIALS: One hundred seven healthy postmenopausal women were recruited in a prospective, randomized, and placebo-controlled 6 months study. Of these, 18 were hysterectomized and received daily oral 0.625 mg CEE. Eighty nine non-hysterectomized women were randomly allocated to one of four groups: a group (22 patients) treated with CEE, 0.625 mg/daily plus MPA 2.5 mg/daily; a group (22 patients) treated with CEE, 0.625 mg/daily plus NA 5 mg/daily; a group (23 patients) treated with raloxifene hydrochloride, 60 mg once daily; and a placebo group (22 patients). Hcy and hs-CRP were measured at baseline and at 3 and 6 months. RESULTS: CEE (20%, P=0.03) and CEE+MPA (59%, P=0.006) increased serum hs-CRP levels significantly, whereas CEE+NA decreased serum hs-CRP by 25% (P=0.01). Raloxifene had no significant effect on serum hs-CRP levels during and after the treatment. In all active treatment groups serum Hcy levels decreased significantly compared to baseline and placebo. CONCLUSIONS: Conjugated equine estrogen, hormone replacement therapies, and raloxifene lower serum Hcy levels to a comparable extent in postmenopausal women. Hs-CRP, as a cardiovascular risk factor, is not influenced by raloxifene, whereas CEE and CEE plus MPA significantly increase hs-CRP levels. Treatment with CEE plus NA reduces serum hs-CRP levels.  相似文献   
48.
This study aimed to analyze NKX3.1 expression in tissue samples of benign prostate hyperplasia (BPH) and in three different prostate cancer categories. The correlation of NKX3.1 expression with clinical and pathologic features of patients having undergone radical prostatectomy also was investigated. NKX3.1 expression was determined in tissue samples obtained from four different histopathological categories: (1) from patients treated with transurethral prostatectomy for BPH (n = 26), (2) localized prostate cancer patients subjected to radical prostatectomy (n = 38), (3) biopsy samples from prostate cancer patients who were metastatic at the initial admission (n = 10), and (4) tissue samples of prostate cancer patients administered antiandrogens, but who had undergone transurethral prostatectomy for infravesical obstruction (n = 11). Standard immunohistochemical staining was performed using an antiserum raised against recombinant human NKX3.1. Staining was seen in all categories of prostatic tissues. Immunohistochemistry staining scores were lower in prostate cancer patients. The staining scores were significantly higher in patients with BPH compared to metastatic or localized prostate cancer patients. Staining scores of patients with BPH and of those under antiandrogen therapy were similar. No significant correlation was found between NKX3.1 expression and tumor volume, Gleason sum scores, the presence of extraprostatic extension, tumor stage, or serum PSA. NKX3.1 expression is significantly decreased in prostate cancer patients when compared to BPH. However, the decline of NKX3.1 expression was not correlated with prostate cancer progression and was not associated with advanced stage. Thus, NKX3.1 expression is not a clinically valuable prognostic factor.  相似文献   
49.

Objective:

The aim of this study was to evaluate the degree of microbial contamination in packaged gutta-percha cones before and during use in clinical conditions.

Material and Methods:

Sealed packages of #15-40 gutta-percha cones were opened under aseptic laboratory conditions. Two gutta-percha cones from each size were randomly drawn and added to tubes containing glass beads and 750 μL of saline. The tubes were vortexed, serially diluted and samples of 250 μL were cultured on agar plates. The plates were incubated at 37°C for 3 days and colonies were counted. The initially sampled packages were distributed to 12 final year dental students. The packages were collected at the end of the first and the third clinical practice days and sampled as described above.

Results:

Baseline microbial counts did not exceed 3 CFU. At the end of the first and the third day, additional contamination was found in five and three of the packages, respectively. The ratio of contaminated packages at the first day and the third day was not significantly different (z-test; p > 0.05). The numbers of microorganisms cultured at the first day (8 ± 9.9 CFU) and the third day (4.5 ± 8.3 CFU) were not significantly different (Wilcoxon signed-rank test; p > 0.05). No significant correlation was found between the number of filled root canals and cultured microorganisms at either the first day (Spearman''s rho; r = 0.481, p = 0.113) or the third day (r = -0.034, p = 0.917).

Conclusions:

Gutta-percha cones taken directly from manufacturer''s sealed package harbored microorganisms. Clinical use of the packages has been found to be associated with additional contamination of the gutta-percha cones. The counts of cultured microorganisms did not correlate well with the number of filled root canals.  相似文献   
50.
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