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21.

Purpose  

To compare macroporous alginate scaffolds with Matrigel for culturing frozen-thawed human primordial follicles in organ culture.  相似文献   
22.
Ticks (n = 663) and fleas (n = 470) collected from domestic animals from southeastern Tunisia were screened for Rickettsia infection using reverse line blot assay. Evidence of spotted fever group Rickettsia was obtained. We detected Rickettsia felis in fleas, Rickettsia massiliae Bar 29 and the Rickettsia conorii Israeli spotted fever strain in ticks, and Rickettsia conorii subsp. conorii and Rickettsia spp. in both arthropods. The sensitivity of the adopted technique allowed the identification of a new association between fleas and R. conorii subsp. conorii species. The presence of these vector-borne Rickettsia infections should be considered when diagnosing this disease in humans in Tunisia.  相似文献   
23.
Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disease of motile cilia. Even though PCD is widely studied, North‐African patients have been rarely explored. In this study, we aim at confirming the clinical diagnosis and explore the genetic spectrum of PCD in a cohort of Tunisian patients. Forty clinically diagnosed patients with PCD belonging to 34 families were recruited from Tunisian pediatric departments. In each proband, targeted capture PCD panel sequencing of the 40 PCD genes was performed. PCD panel sequencing identified bi‐allelic mutations in 82% of the families in eight PCD genes. Remarkably, 23.5% of patients carried the same c.2190del CCDC39 mutation. Single nucleotide polymorphism profiling in six unrelated patients carrying this mutation has revealed a founder effect in North‐African patients. This mutation is estimated to date back at least 1,400–1,750 years ago. The identification of this major allele allowed us to suggest a cost‐effective genetic diagnostic strategy in North‐African patients with PCD.  相似文献   
24.
Duplications of the long arm of the X chromosome are rare. The infantile phenotype shares some resemblance with the Prader-Willi syndrome, presenting severe psychomotor retardation, facial dysmorphic features with a broad face, a small mouth and a thin pointed nose, hypotonia, urogenital malformation and proneness to infections. We report a boy with an additional Xq27-qter chromosome segment translocated onto the short arm of chromosome 3. The karyotype was 46,XY,der(3)t(X;3)(q27.3; p26.3)mat. This cryptic unbalanced X-autosome translocation resulted in Xq27-qter functional disomy and a deletion 3p26.3. A detailed analysis of the constitutional chromosomal changes in the patient was performed using array-CGH, FISH and PCR. The aim was to characterize the size and the location of the duplication Xq27-qter (8.18 Mb) and of the deletion 3p26.3 (1.05 Mb), to establish phenotype-genotype correlations and to offer genetic counselling.  相似文献   
25.
Partial trisomy 9p is one of the most common detected autosomal structural anomalies, so the phenotype-genotype correlation of this rearrangement has been well described. Despite variation in size of the 9p duplications, trisomy 9p syndrome is characterized by typical dysmorphic features and a variable but constant psychomotor and mental retardation. Previously reported phenotype genotype correlation studies proposed that the critical region for phenotype is located in 9p22. We report here on a new patient with partial trisomy 9p13.3→9pter in an 8-year-old boy with typical trisomy 9p dysmorphic features but a normal mental development. Cytogenetics investigations showed that our patient karyotype was 47,XY,+ der(22)t(9;22)(p13.q11) inherited by a 3:1 disjunction of a maternal reciprocal translocation t(9;22)(p13.q11). FISH and array CGH analysis were used to better characterize duplicated chromosomal regions and showed a large duplication of chromosome 9p13.3→9pter associated to microduplication in 22q11.1. The size of the duplications in chromosomes 9p and 22q were estimated about 33.9 and 2.67 Mb, respectively. The comparison between this case and those reported in the literature allows us to support that all syndromes show variability and that not all partial trisomies 9p are associated with intellectual disability.  相似文献   
26.

Purpose

Our aim was to evaluate in anaplastic thyroid carcinoma (ATC) patients the value of 18F-FDG PET/CT compared with total body computed tomography (CT) using intravenous contrast material for initial staging, prognostic assessment, therapeutic monitoring and follow-up.

Methods

Twenty consecutive ATC patients underwent PET/CT for initial staging. PET/CT was performed again during follow-up. The gold standard was progression on imaging follow-up (CT or PET/CT) or confirmation with another imaging modality.

Results

A total of 265 lesions in 63 organs were depicted in 18 patients. Thirty-five per cent of involved organs were demonstrated only with PET/CT and one involved organ only with CT. In three patients, the extent of disease was significantly changed with PET/CT that demonstrated unknown metastases. Initial treatment modalities were modified by PET/CT findings in 25% of cases. The volume of FDG uptake (≥300 ml) and the intensity of FDG uptake (SUVmax ≥18) were significant prognostic factors for survival. PET/CT permitted an earlier assessment of tumour response to treatment than CT in 4 of the 11 patients in whom both examinations were performed. After treatment with combined radiotherapy and chemotherapy, only the two patients with a negative control PET/CT had a confirmed complete remission at 14 and 38 months; all eight patients who had persistent FDG uptake during treatment had a clinical recurrence and died.

Conclusion

FDG PET/CT appears to be the reference imaging modality for ATC at initial staging and seems promising in the early evaluation of treatment response and follow-up.  相似文献   
27.
28.
It is generally believed that some human miscarriages result from embryotoxic factors existing in the sera. To study the embryotoxicity of such sera, 3.5-day-old mouse blastocysts were cultured for 72 h on 80% sera from different groups of women. After 72 h there was no blastocystic development in 53.2% of the cases grown on sera from women after two or more miscarriages, and none in 33.6% of the blastocysts grown on sera from women after one miscarriage, as compared with 8.2% and 12% respectively on control sera. Sera from women with miscarriages were divided into 'high risk' (50% or more embryotoxicity) and 'low risk' (less than 50% embryotoxicity) sera. The 'high risk' sera from two or more miscarriages caused an average of 72.1% undevelopment, while the 'low risk' sera (less than 50% embryotoxicity) from the same group caused 33.6% undevelopment. The 'high risk' sera from one miscarriage were embryotoxic to 55.8% of the blastocysts and the 'low risk' sera from the same group caused only 8.7% undevelopment. No significant differences were found in the mean serum concentrations of folic acid, zinc and copper of many of the experimental groups, in comparison with controls. The embryotoxic factor/s which exist in the 'high risk' sera from women with miscarriages are still not known.  相似文献   
29.
Oral lichen planus (OLP) is a chronic autoimmune disease of unknown etiology that affects the skin and mucosae, including the oral cavity. The disease is characterized by lacy, thin white lines on a violaceous background on the oral mucosa, usually on the inside of the cheeks. The disease is also characterized by chronic inflammation and is often associated with severe pain and a burning sensation in the mouth. The etiopathogenesis of lichen planus is complex, with the involvement of T lymphocytes, mast cells, intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex class II antigens. The immunologic process results in vacuolar degeneration, lysis of basal cells and, ultimately, liquefaction of the basal cells. The precipitating factors of OLP can be: stress, particular foods, dental plaque, systemic illness and poor oral hygiene. Often no medication is necessary for benign disease. In the case of severe pain and the burning sensation, high potency topical corticosteroids remain the most reliably effective treatment. Other available treatments are topical cyclosporine, tacrolimus, retinoids and other immunosuppressive agents. Systemic corticosteroids may be indicated in patients whose condition is unresponsive to topical corticosteroids. However, OLP remains a challenging disease to treat, in spite of the numerous treatments tried in the patient population.  相似文献   
30.
Short-term methotrexate therapy in psoriasis: a study of 197 patients   总被引:2,自引:0,他引:2  
Methotrexate (MTX) is one of the most effective antipsoriatic drugs available. Although it is undeniably hepatotoxic, it can be used safely in most patients with severe psoriasis if established guidelines are followed. Current opinion on the monitoring of hepatic damage is divided, however, and the need for repeated liver biopsies during MTX therapy is being re-examined. We have used MTX in a short-term protocol in our patients with psoriasis for the past 20 years, and have recently attempted to minimize or eliminate the need for liver biopsies using this regimen. Data on 244 psoriatics who were given MTX from 1981 to 2000 have been reviewed. Our protocol entailed the use of weekly oral MTX at the full therapeutic dose during episodes of peak disease activity, with tapering off of MTX when the disease subsided in response to treatment combined with natural/seasonal remission. Intensive topical and heliotherapy were encouraged throughout to facilitate the earliest possible drug withdrawal and the longest possible drug-free interval before the next relapse. Strict inclusion criteria were applied before starting MTX. A total of 243 cycles of MTX therapy have been given to 197 evaluable patients. More than 75% improvement occurred in 88% of patients in 8.5 +/- 5.1 weeks. The mean cumulative dose was 709.3 +/- 369.2 mg and the mean duration of follow-up was 16.5 +/- 9.1 months. Fifteen (6.1%) patients had serious adverse effects requiring the cessation of therapy. Only three patients had deranged liver function tests. Thirty-four pre-MTX and 13 post-MTX liver biopsies were taken, which revealed grade I or II changes that were nonprogressive. Our experience with short-term MTX therapy has enabled us to safely administer MTX to our patients with minimal recourse to liver biopsy. In developing countries, where advanced noninvasive methods for the assessment of liver damage are unaffordable or unavailable, this interrupted, short-term regimen may present an acceptable and safe method of using MTX in carefully selected patients with severe psoriasis.  相似文献   
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