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531.
IntroductionWe aimed to determine whether periodontal health deteriorates after bariatric surgery (BS).MethodsA search was performed in Medline and Embase, for prospective cohort studies with data on change in periodontal parameters after BS. Meta-analysis was performed with available data.ResultsThe results of 4 included studies consistently show significant (p < 0.05) worsening of bleeding on probing (4.21% (95% CI: 0.32, 8.11)), clinical attachment loss (0.16 mm (95% CI: 0.05, 0.27)), periodontal pocket depth (PPD) (0.14 mm (95% CI: 0.06, 0.23)) and percentage of PPD 4–5 mm: 1.72% (95% CI: 0.11, 3.34) 6 months after BS, but no change after 12 months.ConclusionsBS may have a transient negative effect on periodontal health.  相似文献   
532.

Objective

To investigate the trends in the prevalence of diagnosed celiac disease (CD), undiagnosed CD, and people without celiac disease avoiding gluten (PWAG) in the civilian noninstitutionalized US population from 2009 to 2014.

Patients and Methods

We studied the occurrence of CD and PWAG in the 2009 to 2014 National Health and Nutrition Examination Surveys. The serum of all participants aged 6 years or older from the National Health and Nutrition Examination Surveys from 2009 to 2014 was tested for CD serology at Mayo Clinic. Participants were interviewed for a diagnosis of CD and the use of a gluten-free diet (GFD). The design effects of the survey and sample weights were incorporated in all statistical analyses.

Results

In the US general population, the prevalence of CD did not change significantly from 0.7% (95% CI, 0.6%-0.8%) in 2009 to 2010 to 0.8% (95% CI, 0.4%-1.2%) in 2011 to 2012 to 0.7% (95% CI, 0.3%-1.0%) in 2013 to 2014. However, the prevalence of undiagnosed CD decreased from 0.6% in 2009 to 2010 to 0.3% in 2013 to 2014. In contrast, the prevalence of PWAG increased significantly from 0.5% (95% CI, 0.2%-0.9%) in 2009 to 2010 to 1.0% (95% CI, 0.6%-1.4%) in 2011 to 2012 to 1.7% (95% CI, 1.1%-2.4%) in 2013 to 2014 (P=.005 for trend).

Conclusion

Although the overall prevalence of CD remained stable from 2009 to 2014, the proportion of individuals with CD that is hidden considerably decreased. Moreover, the proportion of individuals without CD but following a GFD increased markedly from 2009 to 2014. Long-term health consequences of a GFD warrant further investigation.  相似文献   
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Lee JR  Chung WC  Kim JD  Lee KM  Paik CN  Jung SH  Jung JH  Lee YK  Han SW 《Gut and liver》2011,5(2):149-153

Background/Aims

Gastric epithelial dysplasia is considered a precancerous lesion with a variable clinical course. There is disagreement, however, regarding histology-based diagnoses, which has led to confusion in choosing a therapeutic plan. New objective markers are needed to determine which lesions progress to true malignancy. We measured LINE-1 methylation levels, which have been reported to strongly correlate with the global methylation level in gastric epithelial dysplasia and intramucosal cancer.

Methods

A total of 145 tissue samples were analyzed by two histopathologists. All tissues were excised by therapeutic endoscopic mucosal resection and paired with adjacent normal tissue samples. A modified long interspersed nucleotide elements-combined bisulfite restriction analysis (COBRA-LINE-1) method was used.

Results

Gastric epithelial dysplasia and intramucosal cancer tissues had significantly lower levels of LINE-1 methylation than adjacent normal gastric tissues. High-grade dysplasia and intramucosal cancer were distinguishable from low-grade dysplasia based on LINE-1 methylation levels. Furthermore, the distinction could be determined with high sensitivity and specificity, as shown by the receiver operating characteristic (ROC) curve (AUC, 0.82; 95% confidence interval, 0.74 to 0.88).

Conclusions

LINE-1 methylation levels may provide a diagnostic tool for identifying high-grade dysplasia and intramucosal cancer.  相似文献   
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The first and efficient syntheses of the naturally occurring prenylated stilbenes chiricanine A (2), arahypin-1 (3), trans-arachidin-2 (4), trans-arachidin-3 (5), and arahypin-5 (6) are described. Syntheses of 2 and 3 were accomplished by either a convergent sequence or a one-step reaction starting from pinosylvin. Syntheses of 4, 5, and 6 were achieved from (E)-3,5-bis-methoxymethyl-4'-triisopropylsilyloxystilbene obtained by a Horner-Wadsworth-Emmons reaction between a benzaldehyde possessing bis-methoxymethyl ether groups and a benzyl phosphonate with a triisopropylsilyloxy group.  相似文献   
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OBJECTIVES: The purpose of this study was to identify and characterise the neuropeptide content and the size of trigeminal ganglion (TG) neurons innervating the rat gingivomucosal tissue. DESIGN: Retrograde nerve tracer Fluorogold (FG) was injected into the gingiva (group 1, n=5) or applied into the gingival sulcus (group 2, n=5) of the first right maxillary molar. After 10 days, the ganglia were dissected and FG fluorescence was observed under UV light microscope. Expression of calcitonin gene-related peptide (CGRP) and substance P (SP) in FG-labelled neurons was investigated by immunohistochemistry. Cross-sectional areas of neuron cell bodies containing FG were determined. As a control group, approximately 1000 neuron cell bodies representing the entire TG neuron population was evaluated in five trigeminal ganglia. RESULTS: In group 1, the percentages of neurons containing CGRP (median 63%, range 48-72%) and SP (median 64%, range 54-64%) were significantly greater than in the control group (CGRP: median 43%, range 42-47% and SP: median 23%, range 21-27%). In group 2, only the percentage of neurons containing SP (median 50%, range 40-56%) was significantly greater than in the control group. FG-labelled neurons were predominantly small or medium sized (less than 1200 microm2). The neurons in the group 1 were significantly smaller than in group 2. In both experimental groups, immunopositive neurons were significantly smaller than immunonegative neurons. CONCLUSIONS: The majority of neurons in TG that innervate the rat gingivomucosa are small or medium sized and contain CGRP and SP.  相似文献   
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