Dispersal behaviors stimulated by habitat alterations in golden snub-nosed monkeys(Rhinopithecus roxellana)in the Qinling Mountains, China

DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinling Mountains of China.

Mitochondrial ATP 6 and 8 polymorphisms in irritable bowel syndrome with diarrhea

AIM: To investigate mitochondrial ATP 6 and 8 poly-morphisms in the colon and ileum of patients with ir-ritable bowel syndrome with diarrhea (IBS-D). METHODS: Twenty-eight patients fulfilling the Rome Ⅲ criteria for IBS-D and 28 healthy subjects were in-vestigated. All study participants underwent screening colonoscopy and mucosal biopsies were obtained from the colon and/or terminal ileum. Genomic DNA was ex-tracted from specimens based on standard protocols. Mitochondrial ATP (MT-ATP) 6 and 8 genes in speci-mens were polymerase chain reaction amplified and sequenced. Sequencing data were analyzed via Variant Reporter Software and compared with the reference sequence from Genbank (accession No. NC_012920) to indicate possible polymorphisms. The protocol was registered at www.clinicaltrials.gov as NCT01028898. RESULTS: Twenty-five polymorphic sites of MT-ATP 6 and 8 genes were detected and 12 of them were missense mutations. A median of two polymorphic sites in MT-ATP genes was found in colon specimens of controls while a median of three polymorphic sites was noted in patients with IBS-D (Mann-Whitney test, P=0.012). The variants of the colon and ileum speci-mens from the same subjects were identical in all but one case. Symptom duration in IBS was not found to be a significant factor associated with the mtDNA polymorphism (Spearman correlation, P=0.592). The mitochondrial DNA change at 8860 was present in all cases of both groups. The frequency of the 8701 poly-morphism was found to be the second most frequent; however, no statistical difference was noted between the groups (χ2 test, P=0.584). CONCLUSION: Patients with IBS-D have a higher inci-dence of MT-ATP 6 and 8 polymorphisms than healthy subjects, implying that the mtDNA polymorphism may play a role in IBS-D.

Autofluorescence imaging endoscopy can distinguish non-erosive reflux disease from functional heartburn: A pilot study

AIM: To investigate whether autofluorescence imaging(Af I) endoscopy can distinguish non-erosive reflux disease(NERD) from functional heartburn(fh).METHODS: In this prospective observational trial, 127 patients presenting with typical reflux symptoms for > 6 mo were screened. All the participants underwent endoscopy, during which white light imaging(WLI) was followed by Af I. finally 84 patients with normal esophageal appearance on WLI were enrolled. It was defined as being suggestive of NERD if one or more longitudinal purple lines longer than one centimeter were visualized in the distal part of the esophagus during Af I endoscopy. Ambulatory 24-h multichannel intraluminal impedance and ph monitoring was also performed. After standard proton-pump inhibitor(PPI) tests, subjects were divided into an NERD group and an fh group and the diagnostic performance of Af I endoscopy to differentiate NERD from fh was evaluated.RESULTS: Of 84 endoscopy-negative patients, 36(42.9%) had a normal ph/impedance test. Of these, 26 patients with favorable responses to PPI tests were classified as having NERD. finally 10 patients were diagnosed with fh and the others with NERD. Altogether, 68(81.0%) of the 84 patients were positive on Af I endoscopy. In the NERD group, there were 67(90.5%) patients with abnormal esophageal findings on Af I endoscopy while only 1(10%) patient was positive on Af I endoscopy in the fh group. The sensitivity and specificity of AFI in differentiating NERD from FH were 90.5%(95%CI: 81.5%-96.1%) and 90.0%(95%CI: 55.5%-99.7%), respectively. Meanwhile, the accuracy, positive predictive value and negative predictive value of Af I in differentiating between NERD and fh were 90.5%(95%CI: 84.2%-96.8%), 98.5%(95%CI: 92.1%-99.9%) and 56.3%(95%CI: 30.0%-80.2%), respectively.CONCLUSION: Autofluorescence imaging may serve as a complementary method in evaluating patients with NERD and fh.

抗AD活性天然化合物的结构与功能

阿尔茨海默症(Alzheimer's disease, AD)已成为影响人类健康的第四大杀手,给全球公共健康带来重大影响与挑战.近年来,新型治疗AD药物的研制成为生命与健康领域的重要课题,如何发现具有抗AD活性的苗头分子和先导结构是其中的关键科学问题与技术难点.植物来源的天然化合物具有多骨架、多活性、多靶点的成药性特征.本文综述了AD的发病机制和具有抗AD活性的天然化合物的化学结构与功能,为新型抗AD药物的研制提供参考.

ERF4 interacts with and antagonizes TCP15 in regulating endoreduplication and cell growth in Arabidopsis

Endoreduplication is prevalent during plant growth and development,and is often correlated with large cell and organ size.Despite its prevalence,the transcriptional regulatory mechanisms underlying the transition from mitotic cell division to endoreduplication remain elusive.Here,we characterize ETHYLENE-RESPONSIVEELEMENTBINDING FACTOR 4(ERF4)as a positive regulator of endoreduplication through its function as a transcriptional repressor.ERF4 was specifically expressed in mature tissues in which the cells were undergoing expansion,but was rarely expressed in young organs.Plants overexpressing ERF4 exhibited much larger cells and organs,while plants that lacked functional ERF4 displayed smaller organs than the wild-type.ERF4 was further shown to regulate cell size by controlling the endopolyploidy level in the nuclei.Moreover,ERF4 physically associates with the class I TEOSINTE BRANCHED 1/CYCLOIDEA/PCF(TCP)protein TCP15,a transcription factor that inhibits endoreduplication by activating the expression of a key cell-cycle gene,CYCLIN A2;3(CYCA2;3).A molecular and genetic analysis revealed that ERF4promotes endoreduplication by directly suppressing the expression of CYCA2;3.Together,this study demonstrates that ERF4 and TCP15 function as a module to antagonistically regulate each other?s activity in regulating downstream genes,thereby controlling the switch from the mitotic cell cycle to endoreduplication during leaf development.These findings expand our understanding of how the control of the cell cycle is fine-tuned by an ERF4–TCP15 transcriptional complex.