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91.
Von Recklinghausen neurofibromatosis (NF1) is an autosomal dominant disorder with a prevalence about 1/3,000 (1/2,000-1/5,000 in various population-based studies). About 30-50% of cases are sporadic, resulting from a new mutation. NF1 is fully penetrant by mid-childhood, stigmata, and medical problems (neurological, dermatological, endocrine, ophthalmological, oncological) are highly variable. Advanced paternal age (APA) has been known to increase the risk of new germline mutations that contribute to the presence of a variety of genetic diseases in the human population. The trend in developed countries has been toward higher parental age due to various reasons. In a cross-sectional study, in two university hospital centers, data on parental age of 103 children (41 female) born between 1976 and 2005 with sporadic NF1 were analyzed. Parental age at birth was compared with the Czech general population matched to birth year. The mean NF1 sporadic case paternal age at birth was 32.0 years (95% CI 30.7-33.3 years) compared with 28.8 years (95% CI 28.6-29.1 years) in the general population (P?相似文献   
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We developed and assessed the diagnostic value of a novel quantitative nested real-time (QNRT) PCR assay targeting the internal transcribed spacer region of ribosomal DNA (rDNA) in a guinea pig model of invasive pulmonary aspergillosis. Groups of 5 immunosuppressed animals that were infected using an aerosol chamber with Aspergillus fumigatus conidia were humanely terminated 1 h postinoculation and at days 3, 5, 7, and 11 postchallenge, and lung tissue, bronchoalveolar lavage (BAL) fluid, whole blood, and serum samples were collected. The QNRT PCR results obtained with the serum and BAL fluid were compared to those achieved with galactomannan and (1→3)-β-d-glucan assays. High fungal burden levels were detected by QNRT PCR in both lung tissue and BAL fluid in all infected animals at each time point, and the sensitivity of each assay in BAL fluid was 100% by day 3 and remained so through the remainder of the study. The sensitivity of detection of fungi in whole blood and serum samples was significantly lower, and some samples remained negative by all three assays despite the advanced stage of the infection. From these data, we can conclude that this novel QNRT PCR method was highly sensitive for the detection of A. fumigatus from different types of samples in this model. In addition, BAL fluid samples appeared to be the most suitable for the early diagnosis of invasive pulmonary aspergillosis. When testing serum, the use of a combination of available assays may increase the possibility of early detection of this opportunistic mycosis.  相似文献   
94.

Purpose  

Inactivating germline mutations in the RET proto-oncogene are the major genetic cause of Hirschsprung’s disease (HD). In some cases, HD can be associated with medullary thyroid carcinoma (MTC) that is commonly caused by activating RET mutations.  相似文献   
95.
The growth-associated protein 43 (GAP-43) is known as a marker of regenerating nerve fibers and their continuous remodeling in the adult human skin. The purpose of this pilot study was to investigate a possible role for GAP-43 in the detection of the early stages of small-fiber neuropathy in patients with type 2 diabetes mellitus (DM2) as compared with a well- established and validated parameter - intra-epidermal nerve fiber density (IENFD) of protein gene product 9.5 (PGP 9.5) immunoreactive intra-epidermal C fibers. In a group of 21 patients with DM2 within three years of diagnosis (13 men, 8 women; mean age 53.9±12.8; range 30-74) and a group of 17 healthy volunteers (8 men, 9 women; mean age 55.8±8.5; range 45-70 years), skin punch biopsies were taken from a distal calf and double immunostained with both PGP 9.5 and GAP-43. In healthy controls, 96.8% of 629 PGP 9.5 immunoreactive fibers were immunostained with GAP-43; the proportion of PGP 9.5 intra-epidermal nerve fibers immunoreactive for GAP-43 in control subjects ranged from 86.5 to 100%. In DM2 patients, IENFD was significantly lower compared to controls (median, 1.5 vs. 11.2/mm; p<0.001). The proportion of GAP-43 immunoreactive intraepidermal nerve fibers was significantly lower in DM2 patients compared to healthy controls (73.6% of 337 PGP 9.5 positive fibers; p<0.001); ranged from 0 to 98.1%. In conclusion, these results show that impaired regeneration of intra-epidermal C fibers in the early stages of type 2 diabetes mellitus, as indicated by GAP-43, might be a marker of incipient diabetic neuropathy.  相似文献   
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97.
Ribosomal protein S19 (RPS19) is currently the only gene associated with Diamond-Blackfan anemia (DBA), a rare congenital pure red cell aplasia characterized by normochromic macrocytic anemia, reticulocytopenia, and normocellular bone marrow with a selective deficiency of erythroid precursors. RPS19 is mutated in 25% of DBA patients, but its role in DBA pathogenesis remains elusive. We have identified a novel heterozygous microdeletion in RPS19 in a DBA patient presenting with profound anemia after birth. The deletion of 18 nucleotides (233-250; A in start codon is +1) in exon 4 leads to the elimination of 6 amino acids 78IYGGRQ83, affecting the most conserved stretch of three amino acids (YGG) in RPS19. The mutated allele was not detected in the patient's family members, indicating de novo mutation. Both alleles were expressed at the same level. Using an immunofluorescence technique, the mutated RPS19 protein localized to nucleoli, and its intracellular distribution did not differ from the wild-type RPS19. The deletion of only a few amino acids of this protein with a preserved reading frame is rare, and this type of a mutation could be very helpful in further experiments to define the role of the RPS19 protein in DBA pathogenesis.  相似文献   
98.
99.
Ovarian cancer is the fifth leading cause of cancer death in women. Absence of a reliable biomarker precludes early diagnosis of the disease. To identify new proteins with potential diagnostic or prognostic value for the therapy of ovarian cancer we performed comparative proteomic analysis of sera from ovarian cancer patients and healthy women. We analyzed serum samples from 10 patients diagnosed with epithelial ovarian cancer and 10 age-matched healthy women. To decrease the extremely wide dynamic range of protein concentrations in serum we used combinatorial hexapeptide libraries. Serum samples were then subjected to proteomic 2-DE analysis. Three proteins with differential abundance were found and identified by mass spectrometry: α-1-antitrypsin, apolipoprotein A-IV and retinol-binding protein?4. Identification of α-1-antitrypsin and apolipoprotein A-IV confirms previous studies but the identification of significantly decreased levels of RBP4 in ovarian cancer patients represents a novel observation. We verified the decrease of RBP4 levels in ovarian cancer patient sera by two independent methods and determined absolute RBP4 concentrations in patients and healthy women. We excluded possible non-cancer factors that could be responsible for the observed RBP4 decrease. We propose a connection of RBP4 with epithelial ovarian cancer and advocate the potential of RBP4 as a candidate diagnostic or prognostic biomarker.  相似文献   
100.
Conclusion: Patients with chronic obstructive pulmonary disease (COPD) more frequently suffer from nasal symptoms as well as upper respiratory tract obstruction compared with the healthy population. Objective: The relationship between chronic rhinosinusitis and bronchial asthma has been studied in detail in the past. In recent years, a limited number of authors have also studied involvement of the nose and paranasal sinuses in patients with COPD. Methods: This was an observational cross-sectional study with subsequent prospective assessment; 42 patients with COPD were included. The control group consisted of 12 healthy subjects. All patients with a history of rhinitis or rhinosinusitis and patients with previous surgery of the nose and sinuses were excluded from the study. Clinical variables evaluated were nasal symptoms (SNAQ-11 questionnaire), nasal endoscopy, nasal patency (active rhinomanometry), and computed tomography of paranasal sinuses. Results: In the COPD group, there was a higher occurrence of nasal symptoms and pathological findings on nasal endoscopy compared with the control group. The overall nasal airflow was higher in the control group (compared with COPD patients) and the overall nasal resistance was higher in the COPD group (compared with controls). Pathological opacity of one or more sinuses was confirmed in 38% of COPD patients.  相似文献   
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