The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis (Bromeliaceae) has sterile branch apice...The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis (Bromeliaceae) has sterile branch apices that project outward from the inflorescence. In this study, we evaluate the functional role of sterile apices as support systems for bird foraging behavior. We recorded bird visitation and flower probing in the presence and absence of sterile branches during the spring seasons of 2021 and 2024. The results revealed that experimental plants with excised branches received fewer bird visits and flower probings than control plants, indicating that sterile branches play an important role in the nectar-feeding behavior of passerine birds in P. chilensis.展开更多
Epigenetics is the discipline of regulating cellular activity through chemical modification or modulation of noncoding RNAs without altering the nucleotide sequence.Studies on this topic include the exploration of DNA...Epigenetics is the discipline of regulating cellular activity through chemical modification or modulation of noncoding RNAs without altering the nucleotide sequence.Studies on this topic include the exploration of DNA methylation,histone modification,noncoding RNA regulation,and chromatin remodeling.Derived from the apical tissues of young permanent teeth,stem cells from apical papilla are odontogenic adult stem cells with high proliferation,self-renewal capacity,and differentiation potential.These cells play crucial roles in root formation and development.This article focuses on the two epigenetic regulatory mechanisms of histone modifications and non-coding RNA.This review summarizes,generalizes,and evaluates the status of research on the epigenetic regulation of the multidirectional differentiation of stem cells from the apical papilla,aiming to explore the mechanisms underlying the multidirectional differentiation process of these stem cells.展开更多
BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical chal...BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical challenge.Enhancer of zeste homolog 2(EZH2),a histone H3 lysine 27 methyltransferase,regulates osteogenesis through epigenetic mechanisms,but its role in SCAPs remains unclear.We hypothesized that EZH2 modulates SCAP osteogenic differentiation via interaction with lysine demethylase 2B(KDM2B),offering a target for therapeutic intervention.AIM To investigate the functional role and molecular mechanism of EZH2 in SCAP osteogenic differentiation.METHODS SCAPs were isolated from healthy human third molars(n=6 donors).Osteogenic differentiation was assessed via Alizarin red staining and alkaline phosphatase assays.EZH2 overexpression/knockdown models were established using lentiviral vectors.Protein interactions were analyzed by co-immunoprecipitation,transcriptomic changes via microarray(Affymetrix platform),and chromatin binding by chromatin immunoprecipitation-quantitative polymerase chain reaction.In vivo bone formation was evaluated in immunodeficient mice(n=8/group)transplanted with SCAPs-hydroxyapatite scaffolds.Data were analyzed using Student’s t-test and ANOVA.RESULTS EZH2 overexpression increased osteogenic markers and mineralized nodule formation.In vivo,EZH2-overexpressing SCAPs generated 10%more bone/dentin-like tissue.Co-immunoprecipitation confirmed EZH2-KDM2B interaction,and peptide-mediated disruption of this binding enhanced osteogenesis.Transcriptome analysis identified 1648 differentially expressed genes(971 upregulated;677 downregulated),with pathway enrichment in Wnt/β-catenin signaling.CONCLUSION EZH2 promotes SCAP osteogenesis via antagonistic interaction with KDM2B,and targeted disruption of this axis offers a translatable strategy for bone regeneration.展开更多
Hypertrophic cardiomyopathy(HCM)is a primary myocardial disease characterized by myocardial hypertrophy,excluding other cardiovascular or systemic/metabolic causes of ventricular wall thickening.Apical hypertrophic ca...Hypertrophic cardiomyopathy(HCM)is a primary myocardial disease characterized by myocardial hypertrophy,excluding other cardiovascular or systemic/metabolic causes of ventricular wall thickening.Apical hypertrophic cardiomyopathy(ApHCM)represents a special form of ventricular hypertrophy predominantly affecting the left ventricular apex below the papillary muscles,typically without significant left ventricular outflow tract obstruction.[1,2]ApHCM often coexists with mild coronary artery abnormalities,[3]and reports of acute myocardial infarction with coronary artery stenosis in ApHCM or HCM patients are uncommon.展开更多
Aims: This article describes the apical infection in endodontically treated tooth 4.5 that spread to adjacent tooth 4.4. Case Report: A 52-year-old woman was referred for the presence of radiolucency extending from to...Aims: This article describes the apical infection in endodontically treated tooth 4.5 that spread to adjacent tooth 4.4. Case Report: A 52-year-old woman was referred for the presence of radiolucency extending from tooth 4.5 and mental foramen. Spontaneous symptoms were present. Tooth 4.5 showed poor-quality endodontics. The vitality of tooth 4.4 was negative, even though no mechanical trauma had been reported, nor was caries present. Both teeth were sensitive to percussion. Endodontic re-treatment of 4.5 and endodontic treatment of 4.4 were performed in a single visit. A large amount of endodontic sealer squeezed mesially from the root of tooth 4.5, where a partial horizontal root fracture was hypothesized. 6-, 12-, and 18-month radiographic follow-ups, by both periapical and cone-beam computed tomography (CBCT) analyses, showed incomplete osseous healing. CBCT excluded root fracture on 4.5. Local symptoms were still present. Clinical and radiological conditions led to extractions, and a cystic lesion was enucleated for histopathologic analyses. Histopathologic diagnosis was a periapical cyst. The supposed partial horizontal root fracture of 4.5 was actually a large lateral canal. Although the root canal treatments followed high standards in terms of quality, a persistent chronic infection developed histologically. The cystic lesion was one consistent reason for the unsuccessful healing of 4.5.展开更多
Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages an...Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages and manifests in adults with a suspicion of typical ECG changes of giant T wave inversion in left precordial leads. Transthoracic echocardiography is the mainstay of non-invasive diagnosis and provides a heterogeneous appearance of its morphological features with a spade-shaped LV (left ventricular) cavity. Background of this case study describes the apical HCM in an asymptomatic male at the age of 54 years old and also predicts the mixed and mid-ventricular forms of left ventricular HCM at this region of Thoothukudi in India.展开更多
AIM:To investigate whether miRNA-155(miR-155)dysregulates apical junctional complex(AJC)protein expression in experimental severe acute pancreatitis(SAP).METHODS:Twenty-four male BALB/c mice were randomly assigned to ...AIM:To investigate whether miRNA-155(miR-155)dysregulates apical junctional complex(AJC)protein expression in experimental severe acute pancreatitis(SAP).METHODS:Twenty-four male BALB/c mice were randomly assigned to two groups:the SAP group(n=12)receiving sequential intraperitoneal injection of 50μg/kg caerulein and 10 mg/kg lipopolysaccharide over 6h,and the control group(n=12)receiving intraperitoneal injection of normal saline.Animals were sacrificed3 h following the last injection for collection of blood samples and pancreas and distal ileal segment specimens.Routine pancreas and intestine histology was used to assess SAP pathology and intestinal epithelial barrier damage.Levels of serum amylase,diamine oxidase(DAO),and tumor necrosis factor(TNF)-αwere determined using commercial kits.Total RNA samples were isolated from intestinal epithelial specimens and reversely transcribed into cDNA.miR-155 and RhoA mRNA expression profiles were determined using quantitative real-time polymerase chain reaction.Target genes for miR-155 were predicted using the miRTarBase database,RNA22 and PicTar computational methods.Western blotting was performed to quantitate the protein expression levels of the target gene RhoA,as well as zonula occludens(ZO)-1 and E-cadherin,two AJC component proteins.RESULTS:Intraperitoneal injection of caerulein and lipopolysaccharide successfully induced experimental acute pancreatic damage(SAP vs control,10.0±2.0vs 3.2±1.2,P<0.01)and intestinal epithelial barrier damage(3.2±0.7 vs 1.4±0.7,P<0.01).Levels of serum amylase(21.6±5.1 U/mL vs 14.3±4.2 U/mL,P<0.01),DAO(21.4±4.1 mg/mL vs 2.6±0.8 mg/mL,P<0.01),and TNF-α(61.0±15.1 ng/mL vs 42.9±13.9 ng/mL,P<0.01)increased significantly in SAP mice compared to those in control mice.miR-155 was significantly overexpressed in SAP intestinal epithelia(1.94±0.50 fold vs 1.03±0.23 fold,P<0.01),and RhoA gene containing three miR-155-specific binding sites in the three prime untranslated regions was one of the target genes for miR-155.RhoA(22.7±5.8 folds vs 59.6±11.6 folds,P<0.01),ZO-1(46±18 folds vs68±19 folds,P<0.01),and E-cadherin proteins(48±15 folds vs 77±18 folds,P<0.01)were underexpressed in SAP intestinal epithelia although RhoA mRNA expression was not significantly changed in SAP(0.97±0.18 folds vs 1.01±0.17 folds,P>0.05).CONCLUSION:TNF-α-regulated miR-155 overexpression inhibits AJC component protein syntheses of ZO-1,and E-cadherin by downregulating post-transcriptional RhoA expression,and disrupts intestinal epithelial barrier in experimental SAP.展开更多
As a cell cycle regulator, the Myb-related CDC5 protein was reported to be essential for the G2 phase of the cell cycle in yeast and animals, but little is known about its function in plants. Here we report the functi...As a cell cycle regulator, the Myb-related CDC5 protein was reported to be essential for the G2 phase of the cell cycle in yeast and animals, but little is known about its function in plants. Here we report the functional characterization of the CDC5 gene in Arabidopsis thaliana. Arabidopsis CDC5 （AtCDC5） is mainly expressed in tissues with high cell division activity, and is expressed throughout the entire process of embryo formation. The AtCDC5 loss-of-function mutant is embryonic lethal. In order to investigate the function of AtCDC5 in vivo, we generated AtCDC5-RNAi plants in which the expression of AtCDC5 was reduced by RNA interference. We found that the G2 to M （G2/M） phase transition was affected in the AtCDC5-RNAi plants, and that endoreduplication was increased. Additionally, the maintenance of shoot apical meristem （SAM） function was disturbed in the AtCDC5-RNAi plants, in which both the WUSCHEL （WUS）- CLAVATA （CLV） and the SHOOT MERISTEMLESS （STM） pathways were impaired. In situ hybridization analysis showed that the expression of STMwas greatly reduced in the shoot apical cells of the AtCDC5-RNAi plants. Moreover, cyclinB1 or Histone4 was found to be expressed in some of these cells when the transcript of STM was undetectable. These results suggest that AtCDC5 is essential for the G2/M phase transition and may regulate the function of SAM by controlling the expression ofSTMand WUS.展开更多
AIM To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy(HCM).METHODS We prospectively assessed 20 patient...AIM To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy(HCM).METHODS We prospectively assessed 20 patients(mean age 53 ± 16 years,range:18-81 years,10 were male),with apical HCM. We measured global longitudinal peak systolic strain(GLPSS) in the midwall and endocardium of the left ventricle. RESULTS The diastolic thickness of the 4 apical segments was 16.25 ± 2.75 mm. All patients had a normal global systolicfunction with a fractional shortening of 50% ± 8%. In spite of supernormal left ventricular(LV) systolic function,midwall GLPSS was decreased in all patients,more in the apical(-7.3% ±-8.8%) than in basal segments(-15.5% ±-6.93%),while endocardial GLPPS was significantly greater and reached normal values(apical:-22.8% ±-7.8%,basal:-17.9% ±-7.5%). CONCLUSION This study shows that two-dimensional strain was decreased mainly confined to the mesocardium,while endocardium myocardial deformation was preserved in HCM and allowed to identify subclinical LV dysfunction. This transmural heterogeneity in systolic strain had not been previously described in HCM and could be explained by the distribution of myofibrillar disarray in deep myocardial areas. The clinical application of this novel finding may help further understanding of the pathophysiology of HCM.展开更多
Barrett's esophagus (BE) is characterized by intestinal metaplasia with the differentiated epithelium replaced by another type of epithelium morphologically similar to normal intestinal epithelium. The metaplasia ...Barrett's esophagus (BE) is characterized by intestinal metaplasia with the differentiated epithelium replaced by another type of epithelium morphologically similar to normal intestinal epithelium. The metaplasia is preceded by bile and acid reflux into the esophagus. BE is a premalignant condition associated with increased risk of esophageal cancer, especially esophageal adenocarcinoma. The Caudal-related homeodomain transcription factors Caudal-related homeodomain transcription factor CDX1 and CDX2 are expressed exclusively in the small and large intestine, playing important roles in proliferation and differentiation of intestinal epithelial cells. Ectopic expression of CDX1 and CDX2 occurs in BE. The apical sodium-dependent bile acid transporter (ASBT) is expressed primarily in terminal ileum where it is a key factor for intestinal reabsorption of bile salts. In addition to upregulation of CDX1 and CDX2, ASBT expression is up-regulated in BE. Furthermore, both CDX1/CDX2 and ASBT expressions are down-regulated in high-grade esophageal dysplasia. The alteration of the above-mentioned factors calls for attention: what is the relationship between CDXs and ASBT aberrant expression in BE? In this commentary, we discuss this issue on basis of the recent study done by Ma et al .展开更多
Apical hypertrophic cardiomyopathy(AHCM) is a relatively rare morphologic variant of HCM in which the hypertrophy of myocardium is localized to the left ventricular apex. Symptoms of AHCM might vary from none to other...Apical hypertrophic cardiomyopathy(AHCM) is a relatively rare morphologic variant of HCM in which the hypertrophy of myocardium is localized to the left ventricular apex. Symptoms of AHCM might vary from none to others mimic coronary artery disease including acute coronary syndrome, thus resulting in inappropriate hospitalization. Transthoracic echocardiography is the firstline imaging technique for the diagnosis of hypertrophic cardiomyopathies. However, when the hypertrophy of the myocardium is localized in the ventricular apex might results in missed diagnosis. Aim of this paper is to review the different imaging techniques used for the diagnosis of AHCM and their role in the detection and comprehension of this uncommon disease.展开更多
It is vital to determine the effective photoperiods of maize for making full use of tropical germplasm, which is the foundation for determining the effect of latitude and planting date on the development of photoperio...It is vital to determine the effective photoperiods of maize for making full use of tropical germplasm, which is the foundation for determining the effect of latitude and planting date on the development of photoperiod-sensitive maize cultivars. The objective of this study is to determine the photoperiod-sensitive inductive phase using reciprocal transfer between long- day （LD） （15 h d^-1） and short-day conditions （SD） （9 h d^-1）. For Huangzao 4 and CML288, days to tassel and pollen shedding were recorded, and stem apical meristems （SAM） were observed by a laser scanning confocal microscope. The results show that the seedlings are insensitive to photoperiod when they are very young （juvenile）. However, after this period, LD delays flowering and increases the leaf numbers below the inflorescence, and the length of the interval of the photoperiod-sensitive inductive phase is longer under LD conditions than under SD conditions. Transferred from SD to LD, plants show a sudden decrease in leaf numbers once sufficient SD has been received for flower commitment. While transferred from LD to SD, plants have a continuous increase in leaf numbers during the photoperiod sensitive inductive phase under LD conditions. At the same time, when plants are competent to flowers, the obvious morphology is the elongation of maize SAM. There is an obvious variance of the photoperiod sensitive phase under LD and SD conditions in different maize.展开更多
We describe a patient with asymptomatic apical hypertrophic cardiomyopathy(AHCM)who later developed cardiac arrhythmias,and briefly discuss the diagnostic modalities,differential diagnosis and treatment option for thi...We describe a patient with asymptomatic apical hypertrophic cardiomyopathy(AHCM)who later developed cardiac arrhythmias,and briefly discuss the diagnostic modalities,differential diagnosis and treatment option for this condition.AHCM is a rare form of hypertrophic cardiomyopathy which classically involves the apex of the left ventricle.AHCM can be an incidental finding,or patients may present with chest pain,palpitations,dyspnea,syncope,atrial fibrillation,myocardial infarction,embolic events,ventricular fibrillation and congestive heart failure.AHCM is frequently sporadic,but autosomal dominant inheritance has been reported in few families.The most frequent and classic electrocardiogram findings are giant negative T-waves in the precordial leads which are found in the majority of the patients followed by left ventricular(LV)hypertrophy.A transthoracic echocardiogram is the initial diagnostic tool in the evaluation of ACHM and shows hypertrophy of the LV apex.AHCM may mimic other conditions such as LV apical cardiac tumors,LV apical thrombus,isolated ventricular non-compaction,endomyocardial fibrosis and coronary artery disease.Other modalities,including left ventriculography,multislice spiral computed tomography,and cardiac magnetic resonance imagings are also valuable tools and are frequently used to differentiate AHCH from other conditions.Medications used to treat symptomatic patients with AHCM include verapamil,beta-blockers and antiarrhythmic agents such as amiodarone and procainamide.An implantable cardioverter defibrillator is recommended for high risk patients.展开更多
Apical periodontitis, dominated by dense inflammatory infiltrates and increased osteoclast activities, can lead to alveolar bone destruction and tooth loss. It is believed that miRNA participates in regulating various...Apical periodontitis, dominated by dense inflammatory infiltrates and increased osteoclast activities, can lead to alveolar bone destruction and tooth loss. It is believed that miRNA participates in regulating various biological processes, osteoclastogenesis included. This study aims to investigate the differential expression of miRNAs in rat apical periodontitis and explore their functional target genes. Microarray analysis was used to identify differentially expressed miRNAs in apical periodontitis. Bioinformatics technique was applied for predicting the target genes of differentially expressed miRNAs and their biological functions. The result provided us with an insight into the potential biological effects of the differentially expressed miRNAs and showed particular enrichment of target genes involved in the MAPK signaling pathways. These findings may highlight the intricate and specific roles of miRNA in inflammation and osteoclastogenesis, both of which are key aspects of apical periodontitis, thus contributing to the future investigation into the etiology, under- lying mechanism and treatment of apical periodontitis.展开更多
Calcium hydroxide（CH） is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files（K file, pre-curved ...Calcium hydroxide（CH） is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files（K file, pre-curved K file, EndoActivator, Ultrasonic file, pre-curved ultrasonic file, F file and needle irrigation alone） with apical transportation. Standardized models of curved canal with such apical transportation or not were set up before applying CH to root canal for 7 days. Seven techniques described above were used for its removal. Then the roots were disassembled and digital photos were taken. The ratio of residual CH in the overall canal surface was calculated using the image analyzer image pro plus 6.0. The data were analyzed using one-way ANOVA with post hoc Tukey test. Results revealed that CH was effectively removed（P〈0.05） by using all 6 mechanical methods except irrigation alone. In curved root canals with apical transportation, EndoActivator, pre-curved ultrasonic file and F file were found to be more effective in removing CH than the other four file（P〈0.001）, while there was no significant difference among EndoActivator, pre-curved ultrasonic file and F file groups（P〉0.05）. The percentage of residual CH in the canal with apical transportation was higher than that in the canal without apical transportation（P〈0.05）. In conclusion, CH can be hardly removed completely. Canal with apical transportation will result in insufficient CH removal. EndoActivator, pre-curved ultrasonic file and F file are more effective in the curved root canal with apical transportation.展开更多
To investigate the prevalence of Enterococcus faecalis in saliva and filled root canals of patients requiring endodontic retreatment for apical periodontitis.Patients with apical periodontitis who were referred for en...To investigate the prevalence of Enterococcus faecalis in saliva and filled root canals of patients requiring endodontic retreatment for apical periodontitis.Patients with apical periodontitis who were referred for endodontic retreatment were examined.The type and quality of the restoration,symptoms,quality of obturation were recorded.During retreatment,an oral rinse sample and root canal sample were cultured using brain-heart infusion agar and bile esculinazide agar to select for E.faecalis.The 16S rRNA technique was used to identify E.faecalis.A total of 32 women and 22 men（mean age：38 years;s.d.：11 years） and 58 teeth were studied.The prevalence of E.faecalis was 19% in the saliva and 38% in the root canals.The odds that root canals harbored E.faecalis were increased if the saliva habored this bacterium（odds ratio59.7;95% confidence interval51.8-51.6;P,0.05）.Teeth with unsatisfactory root obturation had more cultivable bacterial species in root canals than teeth with satisfactory root obturation（P,0.05）.E.faecalis is more common in root canals of teeth with apical periodontitis than in saliva.The prevalence of E.faecalis in root canals is associated with the presence of E.faecalis in saliva.展开更多
基金supported by grants FONDECYT 1180850 and 1231757 to RM.
文摘The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis (Bromeliaceae) has sterile branch apices that project outward from the inflorescence. In this study, we evaluate the functional role of sterile apices as support systems for bird foraging behavior. We recorded bird visitation and flower probing in the presence and absence of sterile branches during the spring seasons of 2021 and 2024. The results revealed that experimental plants with excised branches received fewer bird visits and flower probings than control plants, indicating that sterile branches play an important role in the nectar-feeding behavior of passerine birds in P. chilensis.
文摘Epigenetics is the discipline of regulating cellular activity through chemical modification or modulation of noncoding RNAs without altering the nucleotide sequence.Studies on this topic include the exploration of DNA methylation,histone modification,noncoding RNA regulation,and chromatin remodeling.Derived from the apical tissues of young permanent teeth,stem cells from apical papilla are odontogenic adult stem cells with high proliferation,self-renewal capacity,and differentiation potential.These cells play crucial roles in root formation and development.This article focuses on the two epigenetic regulatory mechanisms of histone modifications and non-coding RNA.This review summarizes,generalizes,and evaluates the status of research on the epigenetic regulation of the multidirectional differentiation of stem cells from the apical papilla,aiming to explore the mechanisms underlying the multidirectional differentiation process of these stem cells.
基金Supported by National Key Research and Development Program,No.2022YFA1104401Beijing Natural Science Foundation,No.7222075+1 种基金CAMS Innovation Fund for Medical Sciences,No.2019RU020Innovation Research Team Project of Beijing Stomatological Hospital,No.CXTD202204.
文摘BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical challenge.Enhancer of zeste homolog 2(EZH2),a histone H3 lysine 27 methyltransferase,regulates osteogenesis through epigenetic mechanisms,but its role in SCAPs remains unclear.We hypothesized that EZH2 modulates SCAP osteogenic differentiation via interaction with lysine demethylase 2B(KDM2B),offering a target for therapeutic intervention.AIM To investigate the functional role and molecular mechanism of EZH2 in SCAP osteogenic differentiation.METHODS SCAPs were isolated from healthy human third molars(n=6 donors).Osteogenic differentiation was assessed via Alizarin red staining and alkaline phosphatase assays.EZH2 overexpression/knockdown models were established using lentiviral vectors.Protein interactions were analyzed by co-immunoprecipitation,transcriptomic changes via microarray(Affymetrix platform),and chromatin binding by chromatin immunoprecipitation-quantitative polymerase chain reaction.In vivo bone formation was evaluated in immunodeficient mice(n=8/group)transplanted with SCAPs-hydroxyapatite scaffolds.Data were analyzed using Student’s t-test and ANOVA.RESULTS EZH2 overexpression increased osteogenic markers and mineralized nodule formation.In vivo,EZH2-overexpressing SCAPs generated 10%more bone/dentin-like tissue.Co-immunoprecipitation confirmed EZH2-KDM2B interaction,and peptide-mediated disruption of this binding enhanced osteogenesis.Transcriptome analysis identified 1648 differentially expressed genes(971 upregulated;677 downregulated),with pathway enrichment in Wnt/β-catenin signaling.CONCLUSION EZH2 promotes SCAP osteogenesis via antagonistic interaction with KDM2B,and targeted disruption of this axis offers a translatable strategy for bone regeneration.
文摘Hypertrophic cardiomyopathy(HCM)is a primary myocardial disease characterized by myocardial hypertrophy,excluding other cardiovascular or systemic/metabolic causes of ventricular wall thickening.Apical hypertrophic cardiomyopathy(ApHCM)represents a special form of ventricular hypertrophy predominantly affecting the left ventricular apex below the papillary muscles,typically without significant left ventricular outflow tract obstruction.[1,2]ApHCM often coexists with mild coronary artery abnormalities,[3]and reports of acute myocardial infarction with coronary artery stenosis in ApHCM or HCM patients are uncommon.
文摘Aims: This article describes the apical infection in endodontically treated tooth 4.5 that spread to adjacent tooth 4.4. Case Report: A 52-year-old woman was referred for the presence of radiolucency extending from tooth 4.5 and mental foramen. Spontaneous symptoms were present. Tooth 4.5 showed poor-quality endodontics. The vitality of tooth 4.4 was negative, even though no mechanical trauma had been reported, nor was caries present. Both teeth were sensitive to percussion. Endodontic re-treatment of 4.5 and endodontic treatment of 4.4 were performed in a single visit. A large amount of endodontic sealer squeezed mesially from the root of tooth 4.5, where a partial horizontal root fracture was hypothesized. 6-, 12-, and 18-month radiographic follow-ups, by both periapical and cone-beam computed tomography (CBCT) analyses, showed incomplete osseous healing. CBCT excluded root fracture on 4.5. Local symptoms were still present. Clinical and radiological conditions led to extractions, and a cystic lesion was enucleated for histopathologic analyses. Histopathologic diagnosis was a periapical cyst. The supposed partial horizontal root fracture of 4.5 was actually a large lateral canal. Although the root canal treatments followed high standards in terms of quality, a persistent chronic infection developed histologically. The cystic lesion was one consistent reason for the unsuccessful healing of 4.5.
文摘Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages and manifests in adults with a suspicion of typical ECG changes of giant T wave inversion in left precordial leads. Transthoracic echocardiography is the mainstay of non-invasive diagnosis and provides a heterogeneous appearance of its morphological features with a spade-shaped LV (left ventricular) cavity. Background of this case study describes the apical HCM in an asymptomatic male at the age of 54 years old and also predicts the mixed and mid-ventricular forms of left ventricular HCM at this region of Thoothukudi in India.
基金Supported by The research grants from Shanghai Municipal Science and Technology CommissionNo.114119b2900+1 种基金Shanghai Municipal Key Laboratory of Pancreatic DiseaseNo.P2012006
文摘AIM:To investigate whether miRNA-155(miR-155)dysregulates apical junctional complex(AJC)protein expression in experimental severe acute pancreatitis(SAP).METHODS:Twenty-four male BALB/c mice were randomly assigned to two groups:the SAP group(n=12)receiving sequential intraperitoneal injection of 50μg/kg caerulein and 10 mg/kg lipopolysaccharide over 6h,and the control group(n=12)receiving intraperitoneal injection of normal saline.Animals were sacrificed3 h following the last injection for collection of blood samples and pancreas and distal ileal segment specimens.Routine pancreas and intestine histology was used to assess SAP pathology and intestinal epithelial barrier damage.Levels of serum amylase,diamine oxidase(DAO),and tumor necrosis factor(TNF)-αwere determined using commercial kits.Total RNA samples were isolated from intestinal epithelial specimens and reversely transcribed into cDNA.miR-155 and RhoA mRNA expression profiles were determined using quantitative real-time polymerase chain reaction.Target genes for miR-155 were predicted using the miRTarBase database,RNA22 and PicTar computational methods.Western blotting was performed to quantitate the protein expression levels of the target gene RhoA,as well as zonula occludens(ZO)-1 and E-cadherin,two AJC component proteins.RESULTS:Intraperitoneal injection of caerulein and lipopolysaccharide successfully induced experimental acute pancreatic damage(SAP vs control,10.0±2.0vs 3.2±1.2,P<0.01)and intestinal epithelial barrier damage(3.2±0.7 vs 1.4±0.7,P<0.01).Levels of serum amylase(21.6±5.1 U/mL vs 14.3±4.2 U/mL,P<0.01),DAO(21.4±4.1 mg/mL vs 2.6±0.8 mg/mL,P<0.01),and TNF-α(61.0±15.1 ng/mL vs 42.9±13.9 ng/mL,P<0.01)increased significantly in SAP mice compared to those in control mice.miR-155 was significantly overexpressed in SAP intestinal epithelia(1.94±0.50 fold vs 1.03±0.23 fold,P<0.01),and RhoA gene containing three miR-155-specific binding sites in the three prime untranslated regions was one of the target genes for miR-155.RhoA(22.7±5.8 folds vs 59.6±11.6 folds,P<0.01),ZO-1(46±18 folds vs68±19 folds,P<0.01),and E-cadherin proteins(48±15 folds vs 77±18 folds,P<0.01)were underexpressed in SAP intestinal epithelia although RhoA mRNA expression was not significantly changed in SAP(0.97±0.18 folds vs 1.01±0.17 folds,P>0.05).CONCLUSION:TNF-α-regulated miR-155 overexpression inhibits AJC component protein syntheses of ZO-1,and E-cadherin by downregulating post-transcriptional RhoA expression,and disrupts intestinal epithelial barrier in experimental SAP.
基金Acknowledgments The authors thank Dr Liying Du （Peking University, China） for technical help on the flow cytometric analysis. The authors also thank Dr Zhongchi Liu （University of Maryland, USA）, Dr Chun-Ming Liu （Institute of Botany CAS, China）, Dr Terry Matthew （University of Southampton, UK）, Professor Daochun Kong （Peking University, China） and Dr Naomi Nakayama （Yale University, USA） for critical comments and valuable discussion. This work was supported by the National Natural Science Foundation of China （GN 30625002 to L-J Qu）.
文摘As a cell cycle regulator, the Myb-related CDC5 protein was reported to be essential for the G2 phase of the cell cycle in yeast and animals, but little is known about its function in plants. Here we report the functional characterization of the CDC5 gene in Arabidopsis thaliana. Arabidopsis CDC5 （AtCDC5） is mainly expressed in tissues with high cell division activity, and is expressed throughout the entire process of embryo formation. The AtCDC5 loss-of-function mutant is embryonic lethal. In order to investigate the function of AtCDC5 in vivo, we generated AtCDC5-RNAi plants in which the expression of AtCDC5 was reduced by RNA interference. We found that the G2 to M （G2/M） phase transition was affected in the AtCDC5-RNAi plants, and that endoreduplication was increased. Additionally, the maintenance of shoot apical meristem （SAM） function was disturbed in the AtCDC5-RNAi plants, in which both the WUSCHEL （WUS）- CLAVATA （CLV） and the SHOOT MERISTEMLESS （STM） pathways were impaired. In situ hybridization analysis showed that the expression of STMwas greatly reduced in the shoot apical cells of the AtCDC5-RNAi plants. Moreover, cyclinB1 or Histone4 was found to be expressed in some of these cells when the transcript of STM was undetectable. These results suggest that AtCDC5 is essential for the G2/M phase transition and may regulate the function of SAM by controlling the expression ofSTMand WUS.
文摘AIM To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy(HCM).METHODS We prospectively assessed 20 patients(mean age 53 ± 16 years,range:18-81 years,10 were male),with apical HCM. We measured global longitudinal peak systolic strain(GLPSS) in the midwall and endocardium of the left ventricle. RESULTS The diastolic thickness of the 4 apical segments was 16.25 ± 2.75 mm. All patients had a normal global systolicfunction with a fractional shortening of 50% ± 8%. In spite of supernormal left ventricular(LV) systolic function,midwall GLPSS was decreased in all patients,more in the apical(-7.3% ±-8.8%) than in basal segments(-15.5% ±-6.93%),while endocardial GLPPS was significantly greater and reached normal values(apical:-22.8% ±-7.8%,basal:-17.9% ±-7.5%). CONCLUSION This study shows that two-dimensional strain was decreased mainly confined to the mesocardium,while endocardium myocardial deformation was preserved in HCM and allowed to identify subclinical LV dysfunction. This transmural heterogeneity in systolic strain had not been previously described in HCM and could be explained by the distribution of myofibrillar disarray in deep myocardial areas. The clinical application of this novel finding may help further understanding of the pathophysiology of HCM.
文摘Barrett's esophagus (BE) is characterized by intestinal metaplasia with the differentiated epithelium replaced by another type of epithelium morphologically similar to normal intestinal epithelium. The metaplasia is preceded by bile and acid reflux into the esophagus. BE is a premalignant condition associated with increased risk of esophageal cancer, especially esophageal adenocarcinoma. The Caudal-related homeodomain transcription factors Caudal-related homeodomain transcription factor CDX1 and CDX2 are expressed exclusively in the small and large intestine, playing important roles in proliferation and differentiation of intestinal epithelial cells. Ectopic expression of CDX1 and CDX2 occurs in BE. The apical sodium-dependent bile acid transporter (ASBT) is expressed primarily in terminal ileum where it is a key factor for intestinal reabsorption of bile salts. In addition to upregulation of CDX1 and CDX2, ASBT expression is up-regulated in BE. Furthermore, both CDX1/CDX2 and ASBT expressions are down-regulated in high-grade esophageal dysplasia. The alteration of the above-mentioned factors calls for attention: what is the relationship between CDXs and ASBT aberrant expression in BE? In this commentary, we discuss this issue on basis of the recent study done by Ma et al .
文摘Apical hypertrophic cardiomyopathy(AHCM) is a relatively rare morphologic variant of HCM in which the hypertrophy of myocardium is localized to the left ventricular apex. Symptoms of AHCM might vary from none to others mimic coronary artery disease including acute coronary syndrome, thus resulting in inappropriate hospitalization. Transthoracic echocardiography is the firstline imaging technique for the diagnosis of hypertrophic cardiomyopathies. However, when the hypertrophy of the myocardium is localized in the ventricular apex might results in missed diagnosis. Aim of this paper is to review the different imaging techniques used for the diagnosis of AHCM and their role in the detection and comprehension of this uncommon disease.
文摘It is vital to determine the effective photoperiods of maize for making full use of tropical germplasm, which is the foundation for determining the effect of latitude and planting date on the development of photoperiod-sensitive maize cultivars. The objective of this study is to determine the photoperiod-sensitive inductive phase using reciprocal transfer between long- day （LD） （15 h d^-1） and short-day conditions （SD） （9 h d^-1）. For Huangzao 4 and CML288, days to tassel and pollen shedding were recorded, and stem apical meristems （SAM） were observed by a laser scanning confocal microscope. The results show that the seedlings are insensitive to photoperiod when they are very young （juvenile）. However, after this period, LD delays flowering and increases the leaf numbers below the inflorescence, and the length of the interval of the photoperiod-sensitive inductive phase is longer under LD conditions than under SD conditions. Transferred from SD to LD, plants show a sudden decrease in leaf numbers once sufficient SD has been received for flower commitment. While transferred from LD to SD, plants have a continuous increase in leaf numbers during the photoperiod sensitive inductive phase under LD conditions. At the same time, when plants are competent to flowers, the obvious morphology is the elongation of maize SAM. There is an obvious variance of the photoperiod sensitive phase under LD and SD conditions in different maize.
文摘We describe a patient with asymptomatic apical hypertrophic cardiomyopathy(AHCM)who later developed cardiac arrhythmias,and briefly discuss the diagnostic modalities,differential diagnosis and treatment option for this condition.AHCM is a rare form of hypertrophic cardiomyopathy which classically involves the apex of the left ventricle.AHCM can be an incidental finding,or patients may present with chest pain,palpitations,dyspnea,syncope,atrial fibrillation,myocardial infarction,embolic events,ventricular fibrillation and congestive heart failure.AHCM is frequently sporadic,but autosomal dominant inheritance has been reported in few families.The most frequent and classic electrocardiogram findings are giant negative T-waves in the precordial leads which are found in the majority of the patients followed by left ventricular(LV)hypertrophy.A transthoracic echocardiogram is the initial diagnostic tool in the evaluation of ACHM and shows hypertrophy of the LV apex.AHCM may mimic other conditions such as LV apical cardiac tumors,LV apical thrombus,isolated ventricular non-compaction,endomyocardial fibrosis and coronary artery disease.Other modalities,including left ventriculography,multislice spiral computed tomography,and cardiac magnetic resonance imagings are also valuable tools and are frequently used to differentiate AHCH from other conditions.Medications used to treat symptomatic patients with AHCM include verapamil,beta-blockers and antiarrhythmic agents such as amiodarone and procainamide.An implantable cardioverter defibrillator is recommended for high risk patients.
基金supported by JCPT2011-9 and SKLODSCU 20130012 to XDZNSFC grant 81200760 and SKLODSCU 20130014 to LWZ
文摘Apical periodontitis, dominated by dense inflammatory infiltrates and increased osteoclast activities, can lead to alveolar bone destruction and tooth loss. It is believed that miRNA participates in regulating various biological processes, osteoclastogenesis included. This study aims to investigate the differential expression of miRNAs in rat apical periodontitis and explore their functional target genes. Microarray analysis was used to identify differentially expressed miRNAs in apical periodontitis. Bioinformatics technique was applied for predicting the target genes of differentially expressed miRNAs and their biological functions. The result provided us with an insight into the potential biological effects of the differentially expressed miRNAs and showed particular enrichment of target genes involved in the MAPK signaling pathways. These findings may highlight the intricate and specific roles of miRNA in inflammation and osteoclastogenesis, both of which are key aspects of apical periodontitis, thus contributing to the future investigation into the etiology, under- lying mechanism and treatment of apical periodontitis.
基金supported by the National Natural Science Foundation of China(No.81200781)
文摘Calcium hydroxide（CH） is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files（K file, pre-curved K file, EndoActivator, Ultrasonic file, pre-curved ultrasonic file, F file and needle irrigation alone） with apical transportation. Standardized models of curved canal with such apical transportation or not were set up before applying CH to root canal for 7 days. Seven techniques described above were used for its removal. Then the roots were disassembled and digital photos were taken. The ratio of residual CH in the overall canal surface was calculated using the image analyzer image pro plus 6.0. The data were analyzed using one-way ANOVA with post hoc Tukey test. Results revealed that CH was effectively removed（P〈0.05） by using all 6 mechanical methods except irrigation alone. In curved root canals with apical transportation, EndoActivator, pre-curved ultrasonic file and F file were found to be more effective in removing CH than the other four file（P〈0.001）, while there was no significant difference among EndoActivator, pre-curved ultrasonic file and F file groups（P〉0.05）. The percentage of residual CH in the canal with apical transportation was higher than that in the canal without apical transportation（P〈0.05）. In conclusion, CH can be hardly removed completely. Canal with apical transportation will result in insufficient CH removal. EndoActivator, pre-curved ultrasonic file and F file are more effective in the curved root canal with apical transportation.
基金supported by the National Natural Science Foundation of China(Grant Nos. 30840091 and 81000428)
文摘To investigate the prevalence of Enterococcus faecalis in saliva and filled root canals of patients requiring endodontic retreatment for apical periodontitis.Patients with apical periodontitis who were referred for endodontic retreatment were examined.The type and quality of the restoration,symptoms,quality of obturation were recorded.During retreatment,an oral rinse sample and root canal sample were cultured using brain-heart infusion agar and bile esculinazide agar to select for E.faecalis.The 16S rRNA technique was used to identify E.faecalis.A total of 32 women and 22 men（mean age：38 years;s.d.：11 years） and 58 teeth were studied.The prevalence of E.faecalis was 19% in the saliva and 38% in the root canals.The odds that root canals harbored E.faecalis were increased if the saliva habored this bacterium（odds ratio59.7;95% confidence interval51.8-51.6;P,0.05）.Teeth with unsatisfactory root obturation had more cultivable bacterial species in root canals than teeth with satisfactory root obturation（P,0.05）.E.faecalis is more common in root canals of teeth with apical periodontitis than in saliva.The prevalence of E.faecalis in root canals is associated with the presence of E.faecalis in saliva.
