OBJECTIVE: To investigate the stability of epigallocatechin gallate ( EGCG) powder. METHODS: The content of the sample was determined by HPLC, and the factors affecting the stability of EGCG were studied according to the related guideline stated in China Pharmacopeia. RESULTS: The linear range of EGCG was 7. 76～ 77. 6? g? mL- 1( r=0. 999 9) , with average recovery at 101. 29% ( RSD=0. 76% ) . Exposed to strong illumination, high temperature and high humidity, the color of EGCG powder suffered variant degree of change, but its content experienced no marked change, and no new degraded substances was noted. CONCLUSION: EGCG powder had a sound stability.

Objective:To describe the detail sampling design,weighting,instruments,filed procedures and quality control methods of the epidemiological survey on dementia among community residents in Tongliao City.Methods:A three-stage disproportionate probability sampling design was used to investigate the inhabitants aged 65 years and over in Tongliao City,Inner Mongolia Autonomous Region.The 10/66 Dementia Research Group(10/66 DRG)assessment instruments were used to diagnose dementia,using computer-assisted personal interview mode in the selected older people.Comprehensive quality control methods were implemented throughout the field-work.Results:A total of 166 villages or communities were sampled from nine counties or districts in Tongliao Cit-y.Totally 4 345 older people were interviewed with 96.2％response rate.By calculating sampling design weights,non-response adjustment weights and post-stratification adjustment weights,these weights were multiplied and per-formed trimming adjustment and standardization adjustment to generate final weights.The 171 interviewers were well-trained and qualified to carry out filed interview.Quality control methods included computer data check,audio record check,and telephone check in order to ensure the quality of the survey.Conclusion:This survey is imple-mented using a rigorous sampling design and timely quality control methods,and uses the 10/66 DRG assessment instruments with satisfactory international validity and reliability as survey instruments,which has international cross-cultural comparability.It provides a valid and feasible methodology of epidemiological survey on dementia for further studies in different regions in China.

Interleukin-27 (IL-27), a heterodimeric cytokine, plays a protective role in diabetes. Ghrelin, a gastric hormone, provides a hunger signal to the central nervous system to stimulate food intake. The relationship between IL-27 and ghrelin is still unexplored. Here we investigated that signal transducer and activator of transcription 3 (STAT3)-mechanistic target of rapamycin (mTOR) signaling mediates the suppression of ghrelin induced by IL-27. Co-localization of interleukin 27 receptor subunit alpha (WSX-1) and ghrelin was observed in mouse and human gastric mucosa. Intracerebroventricular injection of IL-27 markedly suppressed ghrelin synthesis and secretion while stimulating STAT3-mTOR signaling in both C57BL/6J mice and high-fat diet-induced-obese mice. IL-27 inhibited the production of ghrelin in mHypoE-N42 cells. Inhibition of mTOR activity induced by siRNA or rapamycin blocked the suppression of ghrelin production induced by IL-27 in mHypoE-N42 cells. siRNA also abolished the inhibitory effect of IL-27 on ghrelin. IL-27 increased the interaction between STAT3 and mTOR in mHypoE-N42 cells. In conclusion, IL-27 suppresses ghrelin production through the STAT3-mTOR dependent mechanism.

Pancreatic cancer induced by mutation KRAS exhibited a higher risk of incidence, recurrence and mortality. C-Myc is downstream of KRAS and can be involved in the regulation of multiple oncogenic pathways and signaling pathways in pancreatic cancer. Over expressing of C-Myc promotes glycolysis and glutamine uptake in pancreatic cancer cells, promotes cell metabolism and proliferation, is an important factor driving the progress and maintenance of pancreatic cancer, and is related to chemotherapy and immunotherapy drug resistance. C-Myc also interacts with cell cyclin-dependent kinase(CDK) and non-coding RNA to regulate the proliferation, development and metastasis of pancreatic cancer. Therefore, targeting C-Myc was regarded as an effective strategy for the treatment of pancreatic cancer. The activation of C-Myc depends on heterodimerization with its partner MAX and thereby paly a role through binding to the canonical E-Box sequence 5’-CACGTG-3’. Researches showed direct targeting of C-Myc can inhibit the growth of pancreatic carcinoma,such as promoting the degradation of C-Myc, inhibiting the binding of C-Myc/MAX and blocking the binding of C-Myc/MAX to E-box. However, direct targeting has been proved challenging because of its special protein structure. Indirect targeting of C-Myc provided a new strategy for the treatment of pancreatic cancer. C-Myc can be indirected targeting through inhibiting transcription and translation of C-Myc, C-Myc-MAX heterodimerization and promote the ubiquitination and degradation of C-Myc, thus affects the occurrence, development and metastasis of pancreatic cancer.

Arrhythmogenic cardiomyopathy (ACM), a fatal heart disease characterized by fibroadipocytic replacement of cardiac myocytes, accounts for 20% of sudden cardiac death and lacks effective treatment. It is often caused by mutations in desmosome proteins, with Desmoglein-2 (DSG2) mutations as a common etiology. However, the mechanism underlying the accumulation of fibrofatty in ACM remains unknown, which impedes the development of curative treatment. Here we investigated the fat accumulation and the underlying mechanism in a mouse model of ACM induced by cardiac-specific knockout of Dsg2 (CS-Dsg2 ^-/-). Heart failure and cardiac lipid accumulation were observed in CS-Dsg2 ^-/- mice. We demonstrated that these phenotypes were caused by decline of fatty acid (FA) β-oxidation resulted from impaired mammalian target of rapamycin (mTOR) signaling. Rapamycin worsened while overexpression of mTOR and 4EBP1 rescued the FA β-oxidation pathway in CS-Dsg2 ^-/- mice. Reactivation of PPARα by fenofibrate or AAV9-Pparα significantly alleviated the lipid accumulation and restored cardiac function. Our results suggest that impaired mTOR-4EBP1-PPARα-dependent FA β-oxidation contributes to myocardial lipid accumulation in ACM and PPARα may be a potential target for curative treatment of ACM.