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41.
A subset of over-expressed microRNAs (miRNAs) identified in parathyroid carcinomas (Ca) compared to normal glands belongs to C19MC, a cluster on chromosome 19q13.4 involved in stem cell biology and tumourigenesis. In this study, the expression of C19MC-MIR371-3 clusters and the molecular mechanisms presiding their modulation were investigated in a series of six normal parathyroids, 24 adenomas (Ad), 15 Ca and five matched metastases. The general expression levels of C19MC or MIR371-3 clusters in Ad lesions did not differ from normal glands, while they distinguished Ad from Ca at unsupervised hierarchical cluster analysis (P=0.0008). MIR517C showed the most significant difference in expression between Ca and Ad (P=0.0003) and it positively correlated with serum calcium, parathormone and tumour weight. In regard to the molecular mechanism determining C19MC cluster activation, we could detect C19MC copy number (CN) gain in ten Ca (67%) extending distal to the MIR371-3 cluster in almost all samples. Conversely, only four Ad (16%) showed C19MC amplification, with one case presenting distal genomic aberration to MIR371-3. Globally, CN variations of 19q13.4 loci were significantly associated with MIR517C up-regulation (P=0.006). Opposite to normal glands where C19MC promoter was methylated, hypomethylation occurred in 15 out of 30 analysed tumours. Though the epigenetic status did not correlate with C19MC miRNA expression levels, loss of C19MC promoter methylation was significantly associated with Ca and metastatic disease (P=0.01). In conclusion, C19MC cluster aberrations are a characteristic of Ca with respect to Ad. Altogether, these evidences point towards a role for 19q13.4 miRNA clusters as oncogenes in parathyroid tumourigenesis.  相似文献   
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We evaluated the efficacy of clodronate for treating active erosive osteoarthritis of the hand and to compare it with hydroxychloroquine. Group A consisted of 24 patients treated for 24 months with clodronate 300 mg i.v. for 7 days, followed by clodronate i.m. 100 mg for 14 days every 3 months. Group B comprised 14 patients treated with hydroxychloroquine 400 mg daily for 30 days, followed by 200 mg daily for the next 11 months. In group A, 21/24 patients completed the trial and obtained significant pain reduction (p < 0.001), Dreiser’s score (p = 0.012), and number of tender joints (p = 0.011). Strength of right (p = 0.04) and left (p = 0.016) hands, physician’s global assessment (p ≤ 0.001), and patient’s global assessment (p = 0.021) improved. In group B, 8/14 patients completed 12 months of the study, which showed the inefficacy of hydroxychloroquine and its lack of acceptance by patients (worsening pain and patient’s global assessment). Therefore, enrolment was stopped. Differences between groups showed a pain decreasing trend for group A and a slightly increasing one for group B (p = 0.018). Physician and patient global assessments showed a strong increase in group A compared with group B (p < 0.001). Clodronate is effective in erosive osteoarthritis; hydroxychloroquine seems to be ineffective.  相似文献   
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BackgroundPancPRO is a computer program that estimates the risk of pancreatic cancer for asymptomatic individuals based on a genetic model of susceptibility and the familial incidence of cancer.AimTo evaluate the distribution of the familial risk in a series of incident cases of pancreatic adenocarcinoma.Materials and methodsThe lifetime risk of pancreatic cancer was calculated by PancPro for a hypothetical 40-year-old son of 570 consecutive probands with pancreatic cancer.ResultsThe 570 risk values were included between 1% and 13%. The distribution was bimodal, with the antimode located at risk = 7.5%. Considering a 10-fold risk over the general population as a threshold for including a subject in a surveillance program, 19 families (3.3%) would be selected, totalling 92 first-degree relatives with age >40 years.ConclusionsPancPro is a valid instrument to rank families based on risk of pancreatic cancer.  相似文献   
44.
A number of effective therapies for the treatment of osteoporosis have become available in recent years. However, uncertainty exists regarding their long-term use and effectiveness. Bisphosphonate treatment, unlike hormone replacement, denosumab or teriparatide, is associated with benefits extended even after treatment discontinuation. The extended benefits are most apparent for alendronate (ALN) and zoledronate (ZOL). A drug holiday might be considered in patients at low-moderate risk and who have been fully compliant with treatment, and who have had a response to treatment. In patients at low-moderate risk of fractures the decision to consider a drug holiday should be balanced also with the safety profile of each treatment.  相似文献   
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BACKGROUND: Exhaled breath contains thousands of volatile organic compounds (VOCs) that could serve as biomarkers of lung disease. Electronic noses can distinguish VOC mixtures by pattern recognition. OBJECTIVE: We hypothesized that an electronic nose can discriminate exhaled air of patients with asthma from healthy controls, and between patients with different disease severities. METHODS: Ten young patients with mild asthma (25.1 +/- 5.9 years; FEV(1), 99.9 +/- 7.7% predicted), 10 young controls (26.8 +/- 6.4 years; FEV(1), 101.9 +/- 10.3), 10 older patients with severe asthma (49.5 +/- 12.0 years; FEV(1), 62.3 +/- 23.6), and 10 older controls (57.3 +/- 7.1 years; FEV(1), 108.3 +/- 14.7) joined a cross-sectional study with duplicate sampling of exhaled breath with an interval of 2 to 5 minutes. Subjects inspired VOC-filtered air by tidal breathing for 5 minutes, and a single expiratory vital capacity was collected into a Tedlar bag that was sampled by electronic nose (Cyranose 320) within 10 minutes. Smellprints were analyzed by linear discriminant analysis on principal component reduction. Cross-validation values (CVVs) were calculated. RESULTS: Smellprints of patients with mild asthma were fully separated from young controls (CVV, 100%; Mahalanobis distance [M-distance], 5.32), and patients with severe asthma could be distinguished from old controls (CVV, 90%; M-distance, 2.77). Patients with mild and severe asthma could be less well discriminated (CVV, 65%; M-distance, 1.23), whereas the 2 control groups were indistinguishable (CVV, 50%; M-distance, 1.56). The duplicate samples replicated these results. CONCLUSION: An electronic nose can discriminate exhaled breath of patients with asthma from controls but is less accurate in distinguishing asthma severities. CLINICAL IMPLICATION: These findings warrant validation of electronic noses in diagnosing newly presented patients with asthma.  相似文献   
50.
Covalent bonding of 7-chloro-4-quinolylazo-octamethoxypillar[5]arene molecules to silylated quartz substrates readily produced a new chromogenic reusable pillararene-coated quartz slide, for the direct UV detection of “transparent” analytes in solution. This device provides an analyte-selective optical response towards linear (di)amines with a highly reproducible optical read-out.

Pillar[5]arene-decorated quartz slides for the direct detection of linear amines and diamines are now available.  相似文献   
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