Unraveling the ties between irritable bowel syndrome and intestinal microbiota

Irritable bowel syndrome(IBS)is the most prevalent functional gastrointestinal disorder.It is a multifactoria disorder.Intestinal microbiota may cause the pathogenesis of IBS by contributing to abnormal gastrointestina motility,low-grade inflammation,visceral hypersensitivity,communication in the gut-brain axis,and so on.Previous attempts to identify the intestinal microbiota composition in IBS patients have yielded inconsistent and occasionally contradictory results.This inconsistency may be due to the differences in the molecular techniques employed,the sample collection and handling methods,use of single samples that are not linked to fluctuating symptoms,or other factors such as patients diets and phenotypic characterizations.Despite these difficulties,previous studies found that the intestina microbiota in some IBS patients was completely different from that in healthy controls,and there does appear to be a consistent theme of Firmicutes enrichment and reduced abundance of Bacteroides.Based on the differences in intestinal microbiota composition,many studies have addressed the roles of microbiotatargeted treatments,such as antibiotics and probiotics,in alleviating certain symptoms of IBS.This review summarizes the current knowledge of the associations between intestinal microbiota and IBS as well as the possible modes of action of intestinal microbiota in the pathogenesis of IBS.Improving the current level of understanding of host-microbiota interactions in IBS is important not only for determining the role of intestinal microbiota in IBS pathogenesis but also for therapeutic modulation of the microbiota.     

Combining Conventional Impressions and Intraoral Scans: A Technique for the Treatment of Complete Denture Patients with Flabby Tissue

The conventional method for impressions of flabby tissue uses modified trays and highly flowable materials, but mucostatic impressions are difficult to achieve due to the viscous and the elastic natures of impression materials. In this report, a technique is presented in which conventional impression and intraoral scanning for a fully edentulous patient with flabby tissue are combined. The definitive impression was obtained by applying appropriate pressure to each tissue area, and the denture can be maintained passively and stable at rest and during function.     

Gender Differences in Factors Associated with Perceived Need and Use of Korean Adolescents Mental Health Services

This study investigated the socio-demographic characteristics and emotional and behavioral factors associated with the perceived need and actual use of adolescent mental health services according to genders in Korea. We assessed 1,857 middle school students aged 14–16 years. We administered a self-reported questionnaire including questions on their socio-demographic data, Korean Youth Self Report, and self perceived need and actual use of mental health services. Overall, 11.6 % of the adolescents demonstrated a self perceived need for mental health services regarding their emotional or behavioral problems, while 2.1 % had sought mental health services. There were discrepancies between the perceived need and actual use. Most adolescents (81.6 %) used mental health services without self-perceived need, and only 3.3 % of adolescents with self-perceived need utilized mental health services. The perceived need of mental health services is positively influenced by the adolescent’s anxious/depressed problems in both genders. The use of them is negatively influenced by the withdrawn problem in adolescent boys, while positively influenced by the aggressive behavior in adolescent girls. To increase the actual use of mental health services more attention needs to be focused on their internalizing problems, such as anxious/depressed and withdrawn problems, in addition to externalizing problems in both genders.     

Validation of a Korean version of the Child Oral Health Impact Profile (COHIP) among 8- to 15-year-old school children

International Journal of Paediatric Dentistry 2012; 22: 292–301 Objectives. The purpose of this study was to assess reliability, discriminant validity, and convergent validity of the Oral Health Impact Profile (COHIP) Korean version in a representative community sample of 8‐ to 15‐year‐old Korean children. Methods. A Korean version of COHIP was developed according to the standard procedure of cross‐cultural adaptation of self‐reported instruments. A representative community sample of 2236 schoolchildren was selected by cluster sampling method. Results. Mean age of the participants was 11.8 years. Mean and median of the overall COHIP score were 103.3 (SD 13.3) and 106, respectively. Internal reliability and retest reliability were excellent with Chronbach’s alpha 0.88 and intraclass correlation coefficient 0.88. Face validity was confirmed with 98% of participants reporting the COHIP questionnaire was easy to answer. Nonclinical factors such as self‐rated oral health or satisfaction with oral health were significantly related with overall COHIP score and five subscale scores (P < 0.001) in a consistent manner. Children with carious permanent teeth and with orthodontic treatment need had highly significantly lower overall COHIP score (P < 0.01). Conclusion. The Korean version of the COHIP was successfully developed. The internal reliability, retest reliability, face validity, discriminant validity, and convergent validity of the COHIP Korean version were confirmed.     

Histone deacetylase 6 functions as a tumor suppressor by activating c-Jun NH2-terminal kinase-mediated beclin 1-dependent autophagic cell death in liver cancer

Ubiquitin-binding histone deacetylase 6 (HDAC6) is uniquely endowed with tubulin deacetylase activity and plays an important role in the clearance of misfolded protein by autophagy. In cancer, HDAC6 has become a target for drug development due to its major contribution to oncogenic cell transformation. In the present study we show that HDAC6 expression was down-regulated in a large cohort of human hepatocellular carcinoma (HCC) patients, and that low expression of HDAC6 was significantly associated with poor prognosis of HCC patients in 5-year overall, disease-free, and recurrence-free survival. Notably, we observed that ectopic overexpression of HDAC6 suppressed tumor cell growth and proliferation in various liver cancer cells, and elicited increased LC3B-II conversion and autophagic vacuole formation without causing apoptotic cell death or cell cycle inhibition. In addition, the sustained overexpression of HDAC6 reduced the in vivo tumor growth rate in a mouse xenograft model. It was also found that HDAC6 mediated autophagic cell death by way of Beclin 1 and activation of the LC3-II pathway in liver cancer cells, and that HDAC6 overexpression activated c-Jun NH2-terminal kinase (JNK) and increased the phosphorylation of c-Jun. In contrast, the induction of Beclin 1 expression was blocked by SP600125 (a specific inhibitor of JNK) or by small interfering RNA directed against HDAC6. CONCLUSION: Our findings suggest that loss of HDAC6 expression in human HCCs and tumor suppression by HDAC6 occur by way of activation of caspase-independent autophagic cell death through the JNK/Beclin 1 pathway in liver cancer and, thus, that a novel tumor suppressor function mechanism involving HDAC6 may be amenable to nonepigenetic regulation.