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Based on several samples of Middle and Late Triassic age, the authors describe a new family of spumellarian Radiolaria – Trimeridianellidae Dumitrica and Tekin, characterized by a three-fold symmetry, a first shell of triangular prism type with 6 primary rays originated at the edges of two bases of the prism, or 3 meridian arches with 3 equatorial rays, and growth of pyloniacean type. The family comprises 4 monospecific new genera (Enneacladus Dumitrica, Endoprisma Dumitrica, Trimeridianella Dumitrica and Tekin, and Tristylopyle Dumitrica), 4 new species and one left in open nomenclature. In spite of their spotty occurrences and low diversity, the authors attempt to trace the evolution of the family, which is considered to be the result of heterochrony in ontogenetic growth, mostly of paedomorphic type. The family seems to be related to the Middle Triassic family Patruliidae Dumitrica with which it shares in common the simple microsphere with 6 primary rays and the pyloniacean mode of growth. 相似文献
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Mutations in SLC34A2 cause pulmonary alveolar microlithiasis and are possibly associated with testicular microlithiasis 总被引:8,自引:0,他引:8 下载免费PDF全文
Corut A Senyigit A Ugur SA Altin S Ozcelik U Calisir H Yildirim Z Gocmen A Tolun A 《American journal of human genetics》2006,79(4):650-656
Pulmonary alveolar microlithiasis (PAM) is a rare disease characterized by the deposition of calcium phosphate microliths throughout the lungs. We first identified a PAM locus by homozygosity mapping to 4p15, then identified, by a candidate-gene approach, the gene responsible for the disease as SLC34A2 (the type IIb sodium-phosphate cotransporter gene), which is involved in phosphate homeostasis in several organs. We identified six homozygous exonic mutations in the seven unrelated patients with PAM we studied. Three of the mutations were frameshifts, one was a chain termination, one was an amino acid substitution, and one was a deletion spanning the minimal promoter and the first exon. Absence of functional protein product of the gene is compatible with calcium phosphate deposition in alveolar airspaces. We show that impaired activity of the phosphate transporter is presumably responsible for the microliths and that PAM is a recessive monogenic disease with full penetrance. Testicular microlithiasis (TM) is a disease that is more common than PAM. It is often associated with cancer and infertility. Since the gene we identified is also expressed in testis, we searched for mutations in subjects with TM. In 2 of the 15 subjects with TM we studied, we identified two rare variants, one synonymous and the other noncoding, that are possibly associated with the condition. 相似文献
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Hayden MR Karuparthi PR Habibi J Lastra G Patel K Wasekar C Manrique CM Ozerdem U Stas S Sowers JR 《Experimental biology and medicine (Maywood, N.J.)》2008,233(9):1109-1123
CONTEXT: The transgenic human islet amyloid polypeptide (HIP) rat model of type 2 diabetes mellitus (T2DM) parallels the functional and structural changes in human islets with T2DM. OBJECTIVE: The transmission electron microscope (TEM) was utilized to observe the ultrastructural changes in islet microcirculation. METHODS: Pancreatic tissue from male Sprague Dawley rats (2, 4, 8, 14 months) were used as controls (SDC) and compared to the 2-, 4-, 8- and 14-month-old HIP rat models. RESULTS: The 2-month-old HIP model demonstrated no islet or microcirculation remodeling changes when compared to the SDC models. The 4-month-old HIP model demonstrated significant pericapillary amyloid deposition and diminution of pericyte foot processes as compared to the SDC models. The 8-month-old model demonstrated extensive islet amyloid deposition associated with pericyte and beta-cell apoptosis when compared with SDC. The 14-month-old HIP model demonstrated a marked reduction of beta-cells and intra-islet capillaries with near complete replacement of islets by amyloidoses. Increased cellularity in the region of the islet exocrine interface was noted in the 4- to 14-month-old HIP models as compared to SDC. In contrast to intra-islet capillary rarefaction there was noticeable angiogenesis in the islet exocrine interface. Pericytes seemed to be closely associated with collagenosis, intra-islet adipogenesis and angiogenesis in the islet exocrine interface. CONCLUSION: The above novel findings regarding the microcirculation and pericytes could assist researchers and clinicians in a better morphological understanding of T2DM and lead to new strategies for prevention and treatment of T2DM. 相似文献
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Martin L?wer Bernhard Y. Renard Jos de Graaf Meike Wagner Claudia Paret Christoph Kneip ?zlem Türeci Mustafa Diken Cedrik Britten Sebastian Kreiter Michael Koslowski John C. Castle Ugur Sahin 《PLoS computational biology》2012,8(9)
Next generation sequencing (NGS) has enabled high throughput discovery of somatic mutations. Detection depends on experimental design, lab platforms, parameters and analysis algorithms. However, NGS-based somatic mutation detection is prone to erroneous calls, with reported validation rates near 54% and congruence between algorithms less than 50%. Here, we developed an algorithm to assign a single statistic, a false discovery rate (FDR), to each somatic mutation identified by NGS. This FDR confidence value accurately discriminates true mutations from erroneous calls. Using sequencing data generated from triplicate exome profiling of C57BL/6 mice and B16-F10 melanoma cells, we used the existing algorithms GATK, SAMtools and SomaticSNiPer to identify somatic mutations. For each identified mutation, our algorithm assigned an FDR. We selected 139 mutations for validation, including 50 somatic mutations assigned a low FDR (high confidence) and 44 mutations assigned a high FDR (low confidence). All of the high confidence somatic mutations validated (50 of 50), none of the 44 low confidence somatic mutations validated, and 15 of 45 mutations with an intermediate FDR validated. Furthermore, the assignment of a single FDR to individual mutations enables statistical comparisons of lab and computation methodologies, including ROC curves and AUC metrics. Using the HiSeq 2000, single end 50 nt reads from replicates generate the highest confidence somatic mutation call set. 相似文献
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Yildirim K Senel K Karatay S Sisecioglu M Kiziltunc A Ugur M Akcay F 《Cell biochemistry and function》2005,23(4):285-289
We conducted this study to assess serum soluble E-selectin (sE-selectin) levels and erythrocyte membrane Na(+)K(+) ATPase activity in patients with rheumatoid arthritis (RA) and correlate the levels with disease activity. Levels of sE-selectin were measured in the serum of 20 patients with RA and 20 control subjects by an enzyme-linked immunosorbant assay. Na(+)K(+) ATPase activity was determined by a colorimetric method in RA patients and healthy controls. There were no statistically significant differences between the two groups with respect to demographic data such as age and sex (p > 0.05). The serum levels of sE-selectin, ESR and C-reactive protein (CRP) in RA patients were significantly higher than in healthy controls (p < 0.001). Erythrocyte membrane Na(+)K(+) ATPase activity was significantly lower in the RA group than in the control group (p < 0.001). Correlation analysis revealed significant positive correlations between soluble E-selectin and ESR (r = 0.457; p < 0.05) and CRP (r = 0.682; p < 0.01) levels. There were statistically significant negative correlations between erythrocyte membrane Na(+)K(+) ATPase activity and ESR (r = -0.450; p < 0.05) and CRP (r = -0.446; p < 0.05) levels. Additionally, a significant negative correlations between sE-selectin and Na(+)K(+) ATPase activity was observed (r = -0.80; p < 0.001). These results show that decreases in erythrocyte membrane Na(+)K(+) ATPase activity and increases in sE-selectin are observed in RA, and that increased levels of sE-selectin may also reflect disease status or activity. 相似文献
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Yesim Güzey Aras Abdülkadir Tunç Belma Doğan Güngen Adil Can Güngen Yusuf Aydemir Bekir Enes Demiyürek 《Cognitive neurodynamics》2017,11(6):565-571
The purpose of this study was to investigate the effects of depression, anxiety and sleep disturbances on cognitive functions in chronic obstructive pulmonary disease (COPD) patients. In this prospective case-control study, demographic data, smoking history, depression, anxiety, sleep quality and cognitive status of 48 COPD patients and 36 healthy volunteers aged 40–90 years were recorded. The Beck depression inventory (BDI), the Beck anxiety inventory (BAI), and Pittsburgh Sleep Quality Index (PSQI) were used to assess depression, anxiety and sleep quality, respectively in COPD patients. Cognitive performance was studied by the mini-mental state examination. The mean age of patients with COPD was 65.3 ± 9.4 years, and disease duration was 9.6 ± 7.8 years. Male sex ratio, smoking, BDI score, BAI score, total PSQI score, sleep latency, sleep duration, average use of sleep aids and sleep disturbances in patients with COPD were significantly higher than the control group (p < 0.05). When cognitive impairment was compared by age, FVC, FEV, FEV/FVC, PEF values and smoking, no statistically significant relationship was found (p > 0.05). A statistically significant relationship was established between cognitive impairment and severity of disease, presence of anxiety, presence of depression and sleep quality. In our study, we found that sleep disorders, depression and anxiety comorbid with COPD increased cognitive impairment as well as the severity of disease. We believe that this finding is important in terms of reducing the risk of cognitive impairment, preventing misdiagnosis and treatment of the aforementioned comorbid diseases. 相似文献
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Ugur?M. Ayturk Javier?A. Couto Steven Hann John?B. Mulliken Kaitlin?L. Williams August?Yue Huang Steven?J. Fishman Theonia?K. Boyd Harry?P.W. Kozakewich Joyce Bischoff Arin?K. Greene Matthew?L. Warman 《American journal of human genetics》2016,98(4):789-795
Congenital hemangioma is a rare vascular tumor that forms in utero. Postnatally, the tumor either involutes quickly (i.e., rapidly involuting congenital hemangioma [RICH]) or partially regresses and stabilizes (i.e., non-involuting congenital hemangioma [NICH]). We hypothesized that congenital hemangiomas arise due to somatic mutation and performed massively parallel mRNA sequencing on affected tissue from eight participants. We identified mutually exclusive, mosaic missense mutations that alter glutamine at amino acid 209 (Glu209) in GNAQ or GNA11 in all tested samples, at variant allele frequencies (VAF) ranging from 3% to 33%. We verified the presence of the mutations in genomic DNA using a combination of molecular inversion probe sequencing (MIP-seq) and digital droplet PCR (ddPCR). The Glu209 GNAQ and GNA11 missense variants we identified are common in uveal melanoma and have been shown to constitutively activate MAPK and/or YAP signaling. When we screened additional archival formalin-fixed paraffin-embedded (FFPE) congenital cutaneous and hepatic hemangiomas, 4/8 had GNAQ or GNA11 Glu209 variants. The same GNAQ or GNA11 mutation is found in both NICH and RICH, so other factors must account for these tumors’ different postnatal behaviors. 相似文献