LncRNA RP11-301G19.1 is required for the maintenance of vascular smooth muscle cell contractile phenotype via sponging miR-17-5P/ATOH8 axis

Long noncoding RNAs (LncRNAs) play essential roles in regulating gene expression in various biological processes. However, the function of lncRNAs in vascular smooth muscle cell (VSMC) transformation remains to be explained. In this work, we discover that a new bone marrow protein (BMP) signaling target, lncRNA RP11-301G19.1, is significantly induced in BMP7-treated VSMCs through lncRNA microarray analysis. Addition of BMP signaling inhibitor LDN-193189 attenuates the expression of ACTA2 and SM-22α, as well as the mRNA level of RP11-301G19.1. Furthermore, lncRNA RP11-301G19.1 is critical to the VSMC differentiation and is directly activated by SMAD1/9. Mechanistically, knocking down of RP11-301G19.1 leads to the decrease of ATOH8, another BMP target, while the forced expression of RP11-301G19.1 reactivates ATOH8. In addition, miR-17-5p, a miRNA negatively regulated by BMP-7, contains predicted binding sites for lncRNA RP11-301G19.1 and ATOH8 3'UTR. Accordingly, overexpression of miR-17-5p decreases the levels of them. Together, our results revealed the role of lncRNA RP11-301G19.1 as a miRNA sponge to upregulate ATOH8 in VSMC phenotype transformation.

STSN-Net: Simultaneous Tooth Segmentation and Numbering Method in Crowded Environments with Deep Learning

Accurate tooth segmentation and numbering are the cornerstones of efficient automatic dental diagnosis and treatment. In this paper, a multitask learning architecture has been proposed for accurate tooth segmentation and numbering in panoramic X-ray images. A graph convolution network was applied for the automatic annotation of the target region, a modified convolutional neural network-based detection subnetwork (DSN) was used for tooth recognition and boundary regression, and an effective region segmentation subnetwork (RSSN) was used for region segmentation. The features extracted using RSSN and DSN were fused to optimize the quality of boundary regression, which provided impressive results for multiple evaluation metrics. Specifically, the proposed framework achieved a top F1 score of 0.9849, a top Dice metric score of 0.9629, and an mAP (IOU = 0.5) score of 0.9810. This framework holds great promise for enhancing the clinical efficiency of dentists in tooth segmentation and numbering tasks.

Convolutional neural network-assisted diagnosis of midpalatal suture maturation stage in cone-beam computed tomography

OBJECTIVES

The selection of treatment for maxillary expansion is closely related to the calcification degree of the midpalatal suture. A classification method for individual assessment of the morphology of midpalatal suture in cone-beam computed tomography (CBCT) is useful for evaluating the calcification degree. Currently, convolutional neural networks (CNNs) have been introduced into the field of oral and maxillofacial imaging diagnosis. This study validated the ability of CNN models in assessing the maturation stage of the midpalatal suture.

METHODS

The existing CNN model ResNet50 was trained to locate the CBCT transverse plane which contained a complete midpalatal suture. ResNet18, ResNet50, RessNet101, Inception-v3, and Efficientnetv2-s models were trained to evaluate the midpalatal suture maturation stage. Multi-class classification metrics, accuracy, recall, precision, F1-score, and area under the curve values from the receiver operating characteristic curve were used to evaluate the performance of the models, and gradient-weighted class activation map technology was utilised to visualise five midpalatal suture maturation stages for each model.

RESULTS

Resnet50 demonstrated an accuracy of 99.74 % in identifying the transverse plane that contained the complete midpalatal suture. The highest accuracies achieved on the two-stage, three-stage, and five-stage maturation classification tests were 95.15, 88.06, and 75.37 %, all of which exceeded the average accuracy of three experienced orthodontists.

CONCLUSIONS

The CNN model can locate the plane of the midpalatal suture in CBCT images and can assist clinicians in assessing the maturation stage of the midpalatal suture to select the means of maxillary expansion.

CLINICAL SIGNIFICANCE

The application of artificial intelligence on CBCT midpalatal suture plane localisation and maturation stage evaluation enhances diagnostic and treatment efficiency and accuracy of individual assessment of midpalatal suture calcification degree. Additionally, it assists the clinical palatal expansion technique in achieving ideal results.

Use and performance of artificial intelligence applications in the diagnosis of chronic apical periodontitis based on cone beam computed tomography imaging

OBJECTIVES

This study aims to investigate the diagnostic application of an artificial intelligence (AI) computer-aided diagnostic system based on a convolutional neural network algorithm in detecting chronic apical periodontitis in cone beam computed tomography (CBCT) images.

METHODS

CBCT raw data of 55 single root chronic apical pe-riodontitis taken in 2nd Dental Center of Peking University School and Hospital from 49 patients from January 2017 to December 2021 were collected, and the chronic apical periodontitis areas were identified by experienced clinicians ma-nually and segmented layer by layer in Materialise Mimics Medical Software. Deep learning of lesion characterization was conducted via AI 3D U-Net, and the network segmentation results were compared manually with the test sets in terms of intersection over union (IOU), Dice coefficient, and pixel accuracy (PA).

RESULTS

In our deep learning algorithm, the IOU for all actual true lesions in test set samples was 92.18%, and the Dice coefficient and the PA index were 95.93% and 99.27%, respectively. Lesion segmentation and volume measurements performed by humans and AI systems showed excellent agreement.

CONCLUSIONS

AI systems based on deep learning methods can be applied for detecting chronic apical periodontitis on CBCT images in clinical applications.

Factors associated with treatment escalation among MS specialists and general neurologists: Results from an International cojoint study

BACKGROUND

Previous studies in multiple sclerosis (MS) showed that therapeutic inertia (TI) affects 60-90% of neurologists and up to 25% of daily treatment decisions. The objective of this study was to determine the most common factors and attribute levels associated with decisions to treatment escalation in an international study in MS care.

METHODS

300 neurologists with MS expertise from 20 countries were invited to participate. Participants were presented with 12 pairs of simulated MS patient profiles described by 13 clinically relevant factors. We used disaggregated discrete choice experiments to estimate the weight of factors and attributes affecting physicians' decisions when considering treatment selection. Participants were asked to select the ideal candidate for treatment escalation from modest to higher-efficacy therapies.

RESULTS

Overall, 229 neurologists completed the study (completion rate: 76.3%). The top 3 weighted factors associated with treatment escalation were: previous relapses (20%), baseline expanded disability status scale [EDSS] (18%), and MRI activity (13%). Patient demographics and desire for pregnancy had a modest influence (≤ 3%). We observed differences in the weight of factors associated with treatment escalation between MS specialists and non-MS specialists.

CONCLUSIONS

Our results provide critical information on factors influencing neurologists' treatment decisions and should be applied to continuing medical education strategies.

Risk factors for postoperative cerebrospinal fluid leakage after transsphenoidal surgery for pituitary adenoma: a meta-analysis and systematic review

OBJECTIVE

Postoperative cerebrospinal fluid (CSF) leakage represents a challenge even for experienced pituitary surgeons. We aimed to quantitatively synthesize data from studies regarding the risk factors for postoperative CSF leakage after transsphenoidal surgery (TSS) for pituitary adenoma (PA).

METHODS

PubMed, Web of Science, The Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), Wanfang database, and VIP database were searched for case-control and cohort studies, focusing on the risk factors associated with postoperative CSF leakage after TSS for PA. Pooled odds ratios (ORs) and 95% confidence intervals were calculated to determine the risk factors.

RESULTS

A total of 34 case-control and cohort studies involving a total of 9,144 patients with PA were included in this systematic review. The overall rate of postoperative CSF leakage after TSS for PA was 5.6%. Tumor size, adenoma consistency, revision surgery, and intraoperative CSF leakage were independent risk factors for postoperative CSF leakage (ORs, 3.18-6.33). By contrast, the endoscopic approach showed a slight protective benefit compared with the microscopic approach in TSS (OR, 0.69).

CONCLUSIONS

This review provides a comprehensive overview of the quality of the evidence base, informing clinical staff of the importance of screening risk factors for postoperative CSF leakage after TSS for PA. More attention should be paid to PA patients at high risk for CSF leakage after TSS to reduce complications and improve prognosis.

Building on existing tools to improve chronic disease prevention and screening in public health: a cluster randomized trial

BACKGROUND

The BETTER (Building on Existing Tools to Improve Chronic Disease Prevention and Screening in Primary Care) intervention was designed to integrate the approach to chronic disease prevention and screening in primary care and demonstrated effective in a previous randomized trial.

METHODS

We tested the effectiveness of the BETTER HEALTH intervention, a public health adaptation of BETTER, at improving participation in chronic disease prevention and screening actions for residents of low-income neighbourhoods in a cluster randomized trial, with ten low-income neighbourhoods in Durham Region Ontario randomized to immediate intervention vs. wait-list. The unit of analysis was the individual, and eligible participants were adults age 40-64 years residing in the neighbourhoods. Public health nurses trained as "prevention practitioners" held one prevention-focused visit with each participant. They provided participants with a tailored prevention prescription and supported them to set health-related goals. The primary outcome was a composite index: the number of evidence-based actions achieved at six months as a proportion of those for which participants were eligible at baseline.

RESULTS

Of 126 participants (60 in immediate arm; 66 in wait-list arm), 125 were included in analyses (1 participant withdrew consent). In both arms, participants were eligible for a mean of 8.6 actions at baseline. At follow-up, participants in the immediate intervention arm met 64.5% of actions for which they were eligible versus 42.1% in the wait-list arm (rate ratio 1.53 [95% confidence interval 1.22-1.84]).

CONCLUSION

Public health nurses using the BETTER HEALTH intervention led to a higher proportion of identified evidence-based prevention and screening actions achieved at six months for people living with socioeconomic disadvantage.

TRIAL REGISTRATION

NCT03052959 , registered February 10, 2017.

A randomized surgical trial of mitral valve repair with leaflet resection versus leaflet preservation on functional mitral stenosis – primary results of the CAMRA CardioLink-2 trial

Background

The gold standard treatment for mitral valve regurgitation due to prolapse involves surgery with annuloplasty and either leaflet resection or leaflet preservation, with placement of artificial neochordae. It has been suggested that leaflet resection may be prone to functional mitral stenosis, whereby a patient may have a higher mitral gradient at peak exercise compared to a leaflet preservation strategy. Although both techniques are widely used, there has been no prospective randomized study conducted to compare these two techniques, particularly in regard to functional mitral stenosis.

Methods

A total of 104 patients with posterior leaflet prolapse were randomized to undergo mitral repair with either leaflet resection (N=54) or leaflet preservation (N=50) at 7 specialized Canadian cardiac centers. Patient age, proportion of female patients, and mean Society of Thoracic Surgeons risk score was 63.9±10.4 years, 19%, and 1.4% for those who underwent leaflet resection, and 66.3±10.8 years, 16%, and 1.9% for those who underwent leaflet preservation, respectively. The primary endpoint was the mean trans-mitral repair gradient at peak exercise 12-months after repair.

Results

Baseline characteristics were similar between the groups. At 12-months, the mean trans-mitral repair gradient at peak exercise in patients who underwent leaflet resection and preservation was 9.1±5.2 and 8.3±3.3 mmHg (P=0.4), respectively. The two groups had similar mean mitral valve gradient at rest (3.2±1.9 mmHg following resection and 3.1±1.1 mmHg following leaflet preservation, P=0.7). There was no between-group difference for the 6-minute walk distance (451±147 m and 481±95 m for the resection and preservation groups, respectively, P=0.3).

Conclusion

We report the first prospective surgical randomized trial to evaluate commonly used mitral valve repair strategies for posterior leaflet prolapse. Leaflet resection and leaflet preservation both yield acceptable results with no difference in postoperative valve gradient and functional status 12-months after surgical mitral valve repair.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Heart and Stroke Foundation of Canada

H3K18ac Primes Mesendodermal Differentiation upon Nodal Signaling

Cellular responses to transforming growth factor β (TGF-β) depend on cell context. Here, we explored how TGF-β/nodal signaling crosstalks with the epigenome to promote mesendodermal differentiation. We find that expression of a group of mesendodermal genes depends on both TRIM33 and nodal signaling in embryoid bodies (EBs) but not in embryonic stem cells (ESCs). Only in EBs, TRIM33 binds these genes in the presence of expanded H3K18ac marks. Furthermore, the H3K18ac landscape at mesendodermal genes promotes TRIM33 recruitment. We reveal that HDAC1 binds to active gene promoters and interferes with TRIM33 recruitment to mesendodermal gene promoters. However, the TRIM33-interacting protein p300 deposits H3K18ac and further enhances TRIM33 recruitment. ATAC-seq data demonstrate that TRIM33 primes mesendodermal genes for activation by maintaining chromatin accessibility at their regulatory regions. Altogether, our study suggests that HDAC1 and p300 are key factors linking the epigenome through TRIM33 to the cell context-dependent nodal response during mesendodermal differentiation.

•

The H3K18ac landscape changes at gene promoters during mesendodermal differentiation

•

Histone acetylation facilitates TRIM33 recruitment to the chromatin

•

HDAC1 and p300 are the key factors for nodal signaling crosstalk with epigenome

•

Chromatin accessibility at mesendodermal genes depends on TRIM33

P5602Comparison of innominate vs axillary artery cannulation for cerebral protection on neurocognitive outcomes in aortic surgery: a pre-specified analysis of the ACE CardioLink-3 randomised trial

Background

Success after aortic surgery depends on avoidance of neurocognitive dysfunction, thus novel adjuncts to proximal aortic surgery must be evaluated for efficacy of cerebral protection during circulatory arrest. We report the primary neurocognitive results from the ACE CardioLink-3 randomised controlled trial comparing innominate to axillary artery cannulation for cerebral protection (NCT02554032).

Methods

The primary safety endpoint was the proportion of patients with new radiologically severe ischaemic cerebral lesions found on post-operative versus pre-operative diffusion weighted magnetic resonance imaging (DW-MRI). Neurocognitive outcomes were assessed using the Mini-Mental State Exam (MMSE), and the Montreal Cognitive Assessment (MoCA). Continuous and binary outcomes were analysed using ANCOVA (controlling for baseline score) and chi-square/Fisher's exact tests.

Results

Of the 111 patients randomised, 102 patients were included in the primary safety per-protocol analysis. The primary safety outcome (significant new ischaemic lesions on DW-MRI) occurred in 34% in the innominate group and 38.8% in the axillary group (OR 0.81; 0.41 to 1.60; P=0.0009 for non-inferiority). Rates of post-operative stroke/transient ischaemic attack, seizure, delirium, and encephalopathy were similar between groups. The rate of patients with a post-operative MoCA score less than 26 was 44.9% and 39.1% in the innominate and axillary groups respectively (P=0.807). A post-operative MMSE score of less than 24 was observed in 2% vs. 6.5% of the patients in the innominate and axillary groups respectively (P=0.866). A >1-point decrease in the MoCA score from pre-operatively to post-operatively was seen in 32.7% and 34.8% in the innominate and axillary groups respectively (P=0.962). A >1-point decrease in the MMSE score from pre-to post-operative was observed in 20.4% in the innominate artery group compared with 30.4% in the axillary group (P=0.346).

Conclusion

Post-operative neurocognitive dysfunction and DW-MRI incidence of severe ischaemic lesions did not differ in patients randomised to innominate artery cannulation vs, conventional axillary artery cannulation, though the burden of new severe ischaemic lesions is high in both groups.

P3753Does empagliflozin modulate the autonomic system among patients with type 2 diabetes and coronary artery disease? Insights from the Holter sub-study of the EMPA-Heart CardioLink-6 Randomised Trial

Introduction

The mechanism behind how empagliflozin, a sodium-glucose co-transporter 2 (SGLT2) inhibitor, reduces all-cause and cardiovascular mortality among patients with type 2 diabetes (T2DM) and coronary artery disease (CAD) is unknown. Autonomic tone, as reflected by changes in heart rate variability (HRV), is an established prognosticator in patients with CAD and/or heart failure.

Purpose

To assess if empagliflozin treatment changes HRV in subjects with T2DM and CAD.

Methods

In the double-blind EMPA-Heart trial, 97 subjects with T2DM and CAD were randomised to empagliflozin 10 mg/day or placebo for 6 months and underwent 24-hour Holter monitoring at baseline and 6 months. Using automated algorithms, time and frequency HRV domain measures were obtained (standard deviation of NN intervals (SDNN); SD of the average NN intervals for each 5-minute segment (SDANN); root mean square of successive RR interval differences (rMSSD); % interval differences of successive NN intervals >50 ms (pNN50); ratio of low to high frequency (LF/HF)). Changes of these HRV parameters were calculated over 6 months. Between-group differences in HRV parameters were compared using ANCOVA.

Results

Complete Holter data (baseline and 6-month) were available for 68% (n=66) of the cohort. The average heart rate (HR) at baseline/6 months was 69.5±9.8 bpm/72.8±8.1 bpm and 76±10.4 bpm/76.5±10.6 in the placebo group and empagliflozin group, respectively. Both groups had similar changes in average HR over 6 months. Key Holter data are summarised in the table. SDNN and SDANN were higher in the placebo vs. empagliflozin group at 6 months; no significant difference was noted for all other measures.

Empagliflozin 10 mg/day (n=33) Placebo (n=33) Adjusted difference between Empagliflozin and Placebo (ANCOVA) Baseline, Mean (SD) 6-month, Mean (SD) Baseline, Mean (SD) 6-month, Mean (SD) Mean, (95% CI) P-value SDNN (ms) 100.49 (43.74) 98.05 (38.86) 109.35 (30.02) 125.08 (43.83) −18.55 (−34.28, −2.82) 0.022 SDANN (ms) 86.84 (39.34) 83.76 (35.53) 94.70 (28.52) 118.28 (77.41) −20.24 (−37.27, −3.21) 0.021 rMSSD (ms) 27.00 (11.84) 27.22 (13.48) 28.00 (11.58) 27.17 (9.38) −1.23 (−6.02, 3.55) 0.608 pNN50 (%) 7.81 (7.59) 8.32 (9.51) 8.26 (7.8) 6.93 (5.35) 0.51 (−2.61, 3.62) 0.746 LF/HF ratio 1.63 (0.52) 1.65 (0.51) 1.53 (0.43) 1.83 (0.82) −0.08 (−0.38, 0.22) 0.602

Conclusions

Among subjects with T2DM and CAD, changes in HRV over 6 months were similar in the empagliflozin and placebo arms suggesting that the mortality benefit conferred by empagliflozin is not associated with positive modulation of autonomic tone.

Acknowledgement/Funding

This trial was supported by an unrestricted investigator-initiated study grant from Boehringer Ingelheim.

Comparison of mRNA expression from Y-chromosome X-degenerate region genes in taurine cattle, yaks and interspecific hybrid bulls

The yattle (dzo) is an interspecific hybrid of the taurine cattle (Bos taurus) and the domestic yak (Bos grunniens). F₁ hybrid yattle bulls are sterile due to spermatogenic arrest and have misregulation of spermatogenesis genes in the testes. However, the expression pattern of Y chromosome-linked genes in cattle, yaks and yattle testes is still unknown. In this study, we analyzed the mRNA expression pattern of 10 genes known to be present as single copies in the X-degenerate region of the bovine male-specific region of the Y chromosome. Using male-specific primers and reverse transcription quantitative PCR, the ubiquitously transcribed tetratricopeptide repeat gene, Y-linked (UTY), oral-facial-digital syndrome 1, Y-linked (OFD1Y) and ubiquitin specific peptidase 9, Y-linked (USP9Y) genes were ubiquitously expressed and significantly more highly expressed in yattle than in cattle and yaks testes (P < 0.001). RNA binding motif protein, Y-linked (RBMY) had testes-specific expression, and eukaryotic translation initiation factor 1A, Y-linked (EIF1AY) was expressed mainly in testis, whereas yattle and cattle did not show significant differences with respect to the expression of RBMY and EIF1AY. Thus, based on the model of yattle bull sterility, the high expression of UTY, OFD1Y and USP9Y may be associated with yattle infertility.

A Continuous Random Walk Model With Explicit Coherence Regularization for Image Segmentation

Random walk is a popular and efficient algorithm for image segmentation, especially for extracting regions of interest (ROIs). One difficulty with the random walk algorithm is the requirement for solving a huge sparse linear system when applied to large images. Another limitation is its sensitivity to seeds distribution, i.e., the segmentation result depends on the number of seeds as well as their placement, which puts a burden on users. In this paper, we first propose a continuous random walk model with explicit coherence regularization (CRWCR) for the extracted ROI, which helps to reduce the seeds sensitivity, so as to reduce the user interactions. Then, a very efficient algorithm to solve the CRWCR model will be developed, which helps to remove the difficulty of solving huge linear systems. Our algorithm consists of two stages: initialization by performing one-dimensional random walk sweeping based on user-provided seeds, followed by the alternating direction scheme, i.e., Peaceman-Rachford scheme for further correction. The first stage aims to provide a good initial guess for the ROI, and it is very fast since we just solve a limited number of one-dimensional random walk problems. Then, this initial guess is evolved to the ideal solution by applying the second stage, which should also be very efficient since it fits well for GPU computing, and 10 iterations are usually sufficient for convergence. Numerical experiments are provided to validate the proposed model as well as the efficiency of the two-stage algorithm.

Ultrasound Elastography supplement assessing nodal status of magnetic resonance imaging staged cervical N0 patients with nasopharyngeal carcinoma

Background

To determine whether ultrasound elastography can distinguish reactive or metastatic small lymph nodes (sLN) of magnetic resonance imaging (MRI) staged cervical N0 patients with nasopharyngeal carcinoma (NPC).

Methods

A pilot study was performed involving the diagnostic performances of conventional high-frequency ultrasound (CHFU) and/or shear wave elastography (SWE) for predicting metastases in sLN of MRI-staged N0 NPC patients with reference to the histologically-proven ultrasound guided core needle biopsy (US-CNB). The diagnosis of CHFU was based on the superficial lymph node ultrasonic criteria with the five-point-scale (FPS). The mean (Emean), minimum (Emin) and maximum (Emax) of the elasticity indices were measured by SWE at the stiffest part of the sLN in kilopascal. Diagnostic performances were analyzed using a receiver operating curve (ROC) on a per-node basis. The authenticity of this article has been validated by uploading the key raw data onto the Research Data Deposit public platform (http://www.researchdata.org.cn), with the approval RDD number as RDDA2017000447.

Results

All 113 cervical sLN of 49 MRI-staged cervical N0 NPC patients underwent evaluation of CHFU and SWE; 38 sLN (FPS < 2) were regarded as benign, which were excluded from subsequent analysis due to none biopsy-proven. And 75 indeterminate sLN (FPS ≥ 2) were referred to US-CNB and revealed 15 (20%) metastases. All SWE elastic indices were significantly higher in malignant sLNs than in benign sLNs (p < 0.05). Moreover, Emax exhibited the highest diagnostic value (AUC:0.733 ± 0.067, p = 0.005) with excellent measurement reproducibility (ICC: 0.786; 95%CI: 0.684, 0.864). CHFU plus SWE was superior to CHFU or SWE alone for predicting metastases in sLN of MRI-staged N0 patients with NPC (p < 0.001).

Conclusions

CHFU plus SWE is an optional non-invasive modality to supplement MRI in assessing cervical nodal status of patients with NPC.

Electronic supplementary material

The online version of this article (10.1186/s40644-019-0199-3) contains supplementary material, which is available to authorized users.

Role of TRIM33 in Wnt signaling during mesendoderm differentiation

Tripartite motif 33 (TRIM33), a member of the transcription intermediate factor 1 (TIF1) family of transcription cofactors, mediates transforming growth factor-beta (TGF-β) signaling through its PHD-Bromo cassette in mesendoderm differentiation during early mouse embryonic development. However, the role of the TRIM33 RING domain in embryonic differentiation is less clear. Here, we report that TRIM33 mediates Wnt signaling by directly regulating the expression of a specific subset of Wnt target genes, and this action is independent of its RING domain. We show that TRIM33 interacts with β-catenin, a central player in Wnt signaling in mouse embryonic stem cells (mESCs). In contrast to previous reports in cancer cell lines, the RING domain does not appear to function as the E3 ligase for β-catenin, since neither knockout nor overexpression of TRIM33 had an effect on β-catenin protein levels in mESCs. Furthermore, we show that although TRIM33 seems to be dispensable for Wnt signaling through a reporter assay, loss of TRIM33 significantly impairs the expression of a subset of Wnt target genes, including Mixl1, in a Wnt signaling-dependent manner. Together, our results indicate that TRIM33 regulates Wnt signaling independent of the E3 ligase activity of its RING domain for β-catenin in mESCs.

Flavokawain A inhibits Cytochrome P450 in in vitro metabolic and inhibitory investigations

ETHNOPHARMACOLOGICAL RELEVANCE

Flavokawain A, the major chalcone in kava extracts, was served as beverages for informal social occasions and traditional ceremonials in most South Pacific islands. It exhibited strong antiproliferative and apoptotic effects against human prostate and urinary bladder cancer cells.

AIM OF THE STUDY

The current study was purposed to investigate the interaction between Flavokawain A and Cytochrome P450, including the inhibitory effects of Flavokawain A on predominant CYP450 isotypes and further clarified the inhibitory mechanism of FKA on CYP450 enzymes. Besides, study about identifying the key CYP450 isotypes responsible for the metabolism of FKA was also performed.

MATERIALS AND METHODS

In this study, probe-based assays with rat liver microsome system were used to characterize the inhibitory effects of FKA. Molecular docking study was performed to further explore the binding site of FKA on CYP450 isoforms. In addition, chemical inhibition experiments using specific inhibitors (a-naphthoflavone, quinidine, sulfamethoxazde, ketoconazole, omeprazole) were performed to clarify the individual CYP450 isoform that are responsible for the metabolism of FKA.

RESULTS

FKA showed significant inhibition on CYP1A2, CYP2D1, CYP2C6 and CYP3A2 activities with IC50 values of 102.23, 20.39, 69.95, 60.22μmol/L, respectively. The inhibition model was competitive, mixed-inhibition, uncompetitive, and noncompetitive for CYP1A2, CYP2D1, CYP2C6 and CYP3A2 enzymes. Molecular docking study indicated the ligand-binding conformation of FKA in the active site of CYP450 isoforms. The chemical inhibition experiments showed that the metabolic clearance rate of Flavokawain A decreased to 19.84%, 50.38%, and 67.02% of the control in the presence of ketoconazole, sulfamethoxazde and a-naphthoflavone.

CONCLUSION

The study showed that Flavokawain A has varying inhibitory effect on CYP450 enzymes and CYP3A2 was the principal CYP isoform contributing to the metabolism of Flavokawain A. Besides, CYP2C6 and CYP1A2 isoforms also play important roles in the metabolism of FKA. Our results provided a basis for better understanding the biotransformation of FKA and prediction of drug-drug interaction of FKA.

The VHL short variant involves in protein quality control

The von Hippel-Lindau (VHL) is the most important and frequently mutated gene in human clear cell renal cell carcinoma (ccRCC). In contrast to its long counterpart, the internal translational variant of VHL protein (VHLs) is evolutionarily conserved. Herein we present evidence that VHLs associates with ribosome complex via interaction with the large subunit 6 (RPL6). Manipulation of VHLs expression significantly alters protein synthesis, cell size and mitochondrial mass. VHLs deficiency leads to remarkable sensitivity to drug treatments eliciting nascent protein mis-folding and translational errors. The ubiquitination of nascent peptides are dramatically increased upon the ectopic over-expression of VHLs, which simultaneously co-localizes with proteasome and thus may facilitate the ubiquitin-proteasome mediated degradation. In summary, VHLs contributes to protein quality control in addition to its canonical function in maintaining homeostasis of hypoxia-induced factors alpha subunit (HIFα) in response to environmental oxygen supply.

A novel VHLα isoform inhibits Warburg effect via modulation of PKM splicing

Von Hippel-Lindau (VHL) is the most frequently mutated gene in clear cell renal carcinoma. Here, we identified a novel translational variant of VHL, termed VHLα, initiated from an alternative translational start site upstream and in frame with the ATG start codon. We showed that VHLα interacts with and regulates heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1), which consequently modulates pyruvate kinase transcript splicing and reprograms cellular glucose metabolism. Our study demonstrated that a novel VHL isoform may function as a tumor suppressor through inhibiting the Warburg effect.

[Effectiveness of bupropion and counseling for smoking cessation]

OBJECTIVE

To evaluate the effectiveness of bupropion for smoking cessation among Chinese smokers at a smoking cessation clinic.

METHODS

A prospective observational study was conducted in a hospital located in Beijing during 2008 and from 28 to 31 October 2014. A total of 287 smokers (265 men and 22 women) were assessed using data from structured questionnaires at baseline and were followed up at 1 and 6 months. Trained physician counselors provided free brief education and individual counseling sessions for all participants at the first visit. A total 131 participants were prescribed bupropion in addition to counseling. The counseling plus bupropion group was compared with the group who underwent counseling without bupropion. Outcomes were self-reported 7-day point prevalence abstinence rates at 1- and 6-month follow-up and continuous abstinence rates at 6-month follow-up. Smoking reduction rates at 1 and 6 months were also measured.

RESULTS

By intention-to-treat analysis, the 7-day point prevalence abstinence rate of the bupropion group at 1 and 6 months was higher than for the counseling-only group: at 1-month follow-up, 26.0% (34/131) vs. 15.4% (24/156), with OR (95% CI) 1.93(1.07-3.46); these rates at 6-month follow-up were 27.8% (35/131) vs. 15.4% (24/156), with OR (95% CI) 2.01(1.12-3.59). The 1-month continuous abstinence rate at 6 months was higher in the bupropion group: 26.0% (34/131) vs. 14.7% (23/156), with OR (95%CI) 2.03(1.12-3.66). Participants in the bupropion group also had a higher smoking reduction rate at 1 month than those in the counseling-only group: 55.0% (72/131) vs. 38.5% (60/156), with OR (95%CI) 1.95 (1.22-3.13).

CONCLUSION

Prescription of bupropion at this smoking cessation clinic was effective in doubling the quitting rates and smoking reduction rates among Chinese smokers.

A randomized trial testing the efficacy of modifications to the nutrition facts table on comprehension and use of nutrition information by adolescents and young adults in Canada

INTRODUCTION

Given the proposed changes to nutrition labelling in Canada and the dearth of research examining comprehension and use of nutrition facts tables (NFts) by adolescents and young adults, our objective was to experimentally test the efficacy of modifications to NFts on young Canadians' ability to interpret, compare and mathematically manipulate nutrition information in NFts on prepackaged food.

METHODS

An online survey was conducted among 2010 Canadians aged 16 to 24 years drawn from a consumer sample. Participants were randomized to view two NFts according to one of six experimental conditions, using a between-groups 2 x 3 factorial design: serving size (current NFt vs. standardized serving-sizes across similar products) x percent daily value (% DV) (current NFt vs. "low/med/high" descriptors vs. colour coding). The survey included seven performance tasks requiring participants to interpret, compare and mathematically manipulate nutrition information on NFts. Separate modified Poisson regression models were conducted for each of the three outcomes.

RESULTS

The ability to compare two similar products was significantly enhanced in NFt conditions that included standardized serving-sizes (p ≤ .001 for all). Adding descriptors or colour coding of % DV next to calories and nutrients on NFts significantly improved participants' ability to correctly interpret % DV information (p ≤ .001 for all). Providing both standardized serving-sizes and descriptors of % DV had a modest effect on participants' ability to mathematically manipulate nutrition information to calculate the nutrient content of multiple servings of a product (relative ratio = 1.19; 95% confidence limit: 1.04-1.37).

CONCLUSION

Standardizing serving-sizes and adding interpretive % DV information on NFts improved young Canadians' comprehension and use of nutrition information. Some caution should be exercised in generalizing these findings to all Canadian youth due to the sampling issues associated with the study population. Further research is needed to replicate this study in a more heterogeneous sample in Canada and across a range of food products and categories.

Mechanism of the reversal effect of mifepristone on drug resistance of the human cervical cancer cell line HeLa/MMC

We examined the ability of mifepristone to reverse the in vitro drug resistance of human cervical cancer cells resistant to mitomycin-C (HeLa/MMC) cells and investigated the mechanism of this effect. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to detect the drug resistance of HeLa/MMC cells and the reversed drug resistance in vitro. Expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and glucosylceramide synthase (GCS) were measured in HeLa and HeLa/MMC cells. The resistance index of HeLa/MMC cells on MMC was reduced from 5.02 to 1.46 after 10 mg/mL mifepristone exposure. A combination of mifepristone upregulated the Bax/Bcl-2 protein expression ratio and apoptosis in HeLa/MMC cells. GCS expression was significantly higher in HeLa/MMC cells than in HeLa cells (P < 0.01), but distinctly declined in both cell lines after mifepristone application (P < 0.01). Mifepristone reversed the resistance of HeLa/MMC cells to MMC in vitro; the overexpression of the GCS gene and the increased expression of apoptosis-related protein Bcl-2 may play important roles in the formation of multidrug resistance in cervical cancer.

Developing human capital for successful implementation of international marine scientific research projects

The oceans play a crucial role in the global environment and the sustainability of human populations, because of their involvement in climate regulation and provision of living and non-living resources to humans. Maintenance of healthy oceans in an era of increasing human pressure requires a high-level understanding of the processes occurring in the marine environment and the impacts of anthropogenic activities. Effective protection and sustainable resource management must be based, in part, on knowledge derived from successful research. Current marine research activities are being limited by a need for high-quality researchers capable of addressing critical issues in broad multidisciplinary research activities. This is particularly true for developing countries which will require the building of capacity for marine scientific research. This paper reviews the current activities aimed at increasing marine research capacity in developing and emerging countries and analyses the challenges faced, including: appropriate alignment of the research goals and societal and policy-relevant needs; training in multidisciplinary research; increasing capacity for overall synthesis of scientific data; building the capacity of technical staff; keeping highly qualified personnel in marine scientific research roles; cross-cultural issues in training; minimising duplication in training activities; improving linkages among human capital, project resources and infrastructure. Potential solutions to these challenges are provided, along with some priorities for action aimed at improving the overall research effort.

[Study of deletion and mutation of p16 gene in primary hepatocellular carcinoma]

OBJECTIVE

To investigate the role the deletion and mutation of p16 gene plays in the pathogenesis of human primary hepatocarcinoma.

METHODS

Thirty-one cases of human hepatocarcinoma, 31 cases of adjacent noncancerous liver cirrhosis and the leukocytes of 8 normal human subjects were analyzed for deletion and mutation in p16 gene exons 1, 2 and introns 1, 2 with comparative multiple PCR and PCR-SSCP.

RESULTS

Deletion of p16 gene exon 1 and partial intron 1 was found in 4 of 31 cases (13/%). No deletion of exon 2 or intron 2 was found. Three patterns of p16 gene intron 1 and 18 bp-flanking sequence in exon 2 at SSCP analysis were observed in hepatocellular carcinoma and corresponding adjacent noncancerous cirrhosis, and two patterns were found in human normal leukocyte DNA. No aberrant single strand at SSCP in p16 gene exon 1 or most part of exon 2 or intron 2 was detected.

CONCLUSION

Low frequency of deletion and rare mutation of p16 suppressor gene occurred in hepatocellular carcinoma.

Determination of 14 chemical constituents in the traditional Chinese medicinal preparation Huangqin-Tang by high performance liquid chromatography

The high performance liquid chromatographic (HPLC) method for the identification and determination of baicalin (BG), wogonoside (WG), oroxylin-A-glucoside (OG), baicalein (B), wogonin (W), orxylin-A (O), paeoniflorin (PF), glycyrrhizic acid (GL), glycyrrhetinic acid (GA), liquiritin (LG), isoliquirition (ILG), liquiritigenin (L), isoliquiritigenin (IL) and ononin (ON) in Huangqin-Tang [Chinese characters: see text] was established. The samples were separated with a Wakosil C18 column (4.6 x 150 mm) by linear gradient elution using A (MeOH-HAC 100:1, v/v)-B (Water-HAC 100:1, v/v) (0 min, 30:70; 15 min, 40:60; 30 min, 60:40; 45 min, 80:20; 60 min, 100:0) as the mobile phase at a flow-rate of 1.0 ml/min. The detection was by diode-array UV/Vis detector (DAD), and the wavelength was set at the range of 200-400 nm. Satisfactory results were obtained within 60 min for the simultaneous determination of the 14 constituents. The repeatability (RSD) of the method was generally less than 2% (n=5, interday and intraday). The recovery of BG was 96.9+/-1.71, WG was 98.9+/-2.99, PF was 99.7+/-0.52, LG was 95.3+/-2.67, GL was 96.7+/-3.44, and GA was 94.8+/-4.16, respectively.

Global analysis of gene expression in pulmonary fibrosis reveals distinct programs regulating lung inflammation and fibrosis

The molecular mechanisms of pulmonary fibrosis are poorly understood. We have used oligonucleotide arrays to analyze the gene expression programs that underlie pulmonary fibrosis in response to bleomycin, a drug that causes lung inflammation and fibrosis, in two strains of susceptible mice (129 and C57BL/6). We then compared the gene expression patterns in these mice with 129 mice carrying a null mutation in the epithelial-restricted integrin beta6 subunit (beta6(-/-)), which develop inflammation but are protected from pulmonary fibrosis. Cluster analysis identified two distinct groups of genes involved in the inflammatory and fibrotic responses. Analysis of gene expression at multiple time points after bleomycin administration revealed sequential induction of subsets of genes that characterize each response. The availability of this comprehensive data set should accelerate the development of more effective strategies for intervention at the various stages in the development of fibrotic diseases of the lungs and other organs.

Development of muscarinic analgesics derived from epibatidine: role of the M4 receptor subtype

Epibatidine, a neurotoxin isolated from the skin of Epipedobates tricolor, is an efficacious antinociceptive agent with a potency 200 times that of morphine. The toxicity of epibatidine, because of its nonspecificity for both peripheral and central nicotinic receptors, precludes its development as an analgesic. During the synthesis of epibatidine analogs we developed potent antinociceptive agents, typified by CMI-936 and CMI-1145, whose antinociception, unlike that of epibatidine, is mediated via muscarinic receptors. Subsequently, we used specific muscarinic toxins and antagonists to delineate the muscarinic receptor subtype involved in the antinociception evoked by these agents. Thus, the antinociception produced by CMI-936 and CMI-1145 is inhibited substantially by 1) intrathecal injection of the specific muscarinic M4 toxin, muscarinic toxin-3; 2) intrathecally administered pertussis toxin, which inhibits the G proteins coupled to M2 and M4 receptors; and 3) s.c. injection of the M2/M4 muscarinic antagonist himbacine. These results demonstrate that the antinociception elicited by these epibatidine analogs is mediated via muscarinic M4 receptors located in the spinal cord. Compounds that specifically target the M4 receptor therefore may be of substantial value as alternative analgesics to the opiates.

[Mutation analysis of the p15 gene exon 2 in human primary hepatocarcinoma]

To investigate the role p15 gene plays in the pathogenesis of human primary hepatocarcinoma, 35 human hepatocarcinomas, 35 cases of adjacent non-cancerous liver cirrhosis and the blood cells of 10 normal human were analyzed for somatic mutation in p15 gene with PCR-SSCP. One case of adjacent non-cancerous liver cirrhosis showed abnormal migration single strand. In the hepatocarcinomas and in the other cases of adjacent non-cancerous liver cirrhosis, no mutation was found. Cloning and sequencing of the amplified abnormal migration single strand DNA revealed that it contained a wild type exon 2 of p15 gene in 345 bp length. The results indicate that the inaction of p15 gene by point mutation is a very uncommon event in human hepatocarcinoma.

Factors regulating production of alpha-galactosidase from Bacillus sp. JF2

Certain factors affecting the production of cell-associated alpha-galactosidase by Bacillus sp. JF2 were investigated. The intention was to maximize alpha-galactosidase activity of potential commercial application, by consecutive optimization of growth media and conditions. The highest alpha-galactosidase activity was obtained when grown on melibiose, whereas sucrose inhibited the production of alpha-galactosidase, alpha-Galactosidase production was optimally active at pH 7.5 and 55 degrees C. It was identified that a soy effluent stream could be used as the best carbon source for alpha-galactosidase by Bacillus sp. JF2.

Estrogen-related receptor alpha 1 functionally binds as a monomer to extended half-site sequences including ones contained within estrogen-response elements

The human estrogen-related receptor alpha 1 (hERR alpha 1) is an orphan member of the steroid/thyroid hormone receptor superfamily. A cDNA encoding this protein was originally isolated on the basis of sequence similarity in its DNA-binding domain with estrogen receptor alpha (ER alpha). Previously, we reported the purification of hERR alpha 1 from HeLa cell nuclear extracts on the basis of its ability to bind two sites in the late promoter of simian virus 40 (SV40). We have now determined the primary structure and the DNA and protein binding specificities of hERR alpha 1 and developed in vivo and in vitro assays for its functional activities. hERR alpha 1 was found to bind as a monomer, with a high-affinity binding site containing the extended half-site sequence 5'-TCAAG-GTCA-3'. Binding sites for hERR alpha 1 were identified in many cellular promoters, including some that were previously shown to function as estrogen-response elements (EREs). hERR alpha 1 was shown to function as a sequence-specific repressor of the SV40 late promoter in both cell culture and cell-free transcription systems. It was also shown to interact with both ER alpha and the transcription factor TFIIB by direct protein-protein contacts. Thus, hERR alpha 1 may play a role in the response of some genes to estrogen via heterodimerization with ERs or competition with ERs for binding to EREs.

Direct modulation of simian virus 40 late gene expression by thyroid hormone and its receptor

Transcription of the late genes of simian virus 40 (SV40) is repressed during the early phase of the lytic cycle of infection of primate cells by the binding of cellular factors, called IBP-s, to the SV40 late promoter; repression is relieved after the onset of viral DNA replication by titration of these repressors (S. R. Wiley, R. J. Kraus, F. R. Zuo, E. E. Murray, K. Loritz, and J. E. Mertz, Genes Dev. 7:2206-2219, 1993). Recently, we showed that IBP-s consists of several members of the steroid/thyroid hormone receptor superfamily (F. Zuo and J. E. Mertz, Proc. Natl. Acad. Sci. USA 92:8586-8590, 1995). Here, we show that the thyroid hormone receptor TRalpha1, in combination with retinoid X receptor alpha (RXRalpha), is specifically bound at the transcriptional initiation site of the major late promoter of SV40. This binding repressed transcription from the SV40 late promoter by preventing the formation of pre-initiation complexes. Addition of the thyroid hormone 3,5,3'-L-triiodothyronine (T3) resulted in reversal of this repression in cotransfected CV-1 cells. Interestingly, repression did not occur when this thyroid response element (TRE) was translocated to 50 bp upstream of the major late initiation site. Binding of TRalpha1/RXRalpha heterodimers to this TRE induced bending of the promoter DNA. We conclude that hormones and their receptors can directly affect the expression of SV40, probably by affecting protein-protein and protein-DNA interactions involved in the formation of functional preinitiation complexes.

Simian virus 40 late gene expression is regulated by members of the steroid/thyroid hormone receptor superfamily

Transcription of the late genes of simian virus 40 (SV40) is repressed during the early phase of the lytic cycle of infection of binding of cellular factors, called IBP-s, to the SV40 late promoter; repression is relieved after the onset of viral DNA replication by titration of these repressors. Preliminary data indicated that one of the major components of IBP-s was human estrogen-related receptor 1 (hERR1). We show here that several members of the steroid/thyroid hormone receptor superfamily, including testis receptor 2, thyroid receptor alpha 1 in combination with retinoid X receptor alpha, chicken ovalbumin upstream promoter transcription factors 1 and 2 (COUP-TF1 and COUP-TF2), as well as hERR1, possess the properties of IBP-s. These receptors bind specifically to hormone receptor binding sites present in the SV40 major late promoter. Recombinant COUP-TF1 specifically represses transcription from the SV40 major late promoter in a cell-free transcription system. Expression of COUP-TF1, COUP-TF2, or hERR1 in monkey cells results in repression of the SV40 late promoter, but not the early promoter, in the absence of the virally encoded large tumor antigen. Overexpression of COUP-TF1 leads to a delay in the early-to-late switch in SV40 gene expression during the lytic cycle of infection. Thus, members of this superfamily can play major direct roles in regulating expression of SV40. Possibly, natural or synthetic ligands to these receptors can serve as antiviral drugs. Our findings also provide the basis for the development of assays to screen for the ligands to testis receptor 2 and hERR1.

[Simultaneous assay of Ca(2+)-ATPase and Na+, K(+)-ATPase activities of hemolysate by malachite green colorimetric method]

Activities of Ca(2+)-ATPase and Na+, K(+)-ATPase of hemolysate were simultaneously determined by a colorimetric method with malachite green dye. In the presence of Ca2+, EGTA or ouabain, inorganic phosphate released from ATP by hypotonic saponin-treated red cell lysate was used to estimate the activities of Ca(2+)-ATPase and Na2+, K(+)-ATPase. The method is simple, sensitive and stable for at least 4 h. The effects of concentration of saponin and Ca2+, the storage of hemolysate, and the activator and inhibitor of the enzymes on activity were discussed.

SV40 early-to-late switch involves titration of cellular transcriptional repressors

We have purified factors from HeLa cell nuclear extracts that bind to the transcriptional initiation site of the SV40 major late promoter (SV40-MLP). The resulting fraction consists predominantly of three proteins, collectively called initiator-binding protein of SV40 (IBP-s) with electrophoretic mobilities of approximately 45-55 kD. Gel mobility-shift and DNase I-protection analyses indicate that each of these three proteins associates with high affinity to sequences located at the initiation site and 55 bp downstream of it. IBP-s-binding sites with lower affinities are located at +5 and +30. Addition of purified IBP-s to a cell-free transcription system represses transcription from the SV40-MLP, but not the SV40 early promoter. SV40 mutants lacking the two strongest IBP-s-binding sites (1) are not repressed by the addition of IBP-s in vitro, (2) overproduce late RNA (relative to wild-type SV40) at low, but not high, template copy number in vitro, and (3) exhibit increased levels of late RNA at early, but not late, times after transfection into CV-1 cells. Therefore, IBP-s is a cellular repressor of transcription of the SV40-MLP that may, in large part, be responsible for the replication-dependent component of the early-to-late shift in SV40 gene expression. Partial amino acid sequence data obtained from the approximately 55-kD component of IBP-s indicate that it is hERR1, an orphan member of the steroid-thyroid hormone receptor superfamily. These findings suggest simple molecular mechanisms by which hormones may modulate expression of viral late genes. We speculate that activation of expression of the late genes of other viruses may occur by similar mechanisms.