Proteomics of Tear in Inactive Thyroid-Associated Ophthalmopathy

BACKGROUND

Thyroid-associated ophthalmopathy (TAO), one of the most common orbital diseases in adults, seriously reduces patients' quality of life. Although human tear proteomics identified many abnormal expressed proteins and proposed several pathogeneses of TAO, most of these studies focused on the active stage or mixed types in TAO. In this study we identified significantly changed proteins and preliminary revealed the potential signalling pathways and mechanisms of TAO with the late, inactive stage.

PATIENTS AND METHODS

Tears from TAO patients (n=6) with a CAS score < 3 and 6 control healthy subject were collected. The pooled tears were further fractionated using high pH reversed-phase chromatography, then submitted to LC-MS/MS and subsequent bioinformatic analysis.

RESULTS

Proteomic profiling identified 107 significantly changed proteins between the inactive stage of TAO patients and healthy cases. Among these proteins, 62 were upregulated, and 45 were downregulated in TAO cases compared to healthy individuals. Enrichment analysis revealed that the immune system, cell cycle, metabolism (carbohydrate metabolism and metabolism of cofactors and vitamins), protein synthesis and degradation might play a vital role in the progress of inactive TAO. The present investigation represents the first proteomic tear study of TAO patients in the inactive stage.

CONCLUSION

The results shed light on the differences between inactive TAO patients and healthy cases, thus enabling us to understand better the molecular mechanisms and potential targets for the treatment of inactive TAO.

Circular RNA ZNF292 affects proliferation and apoptosis of hepatocellular carcinoma cells by regulating Wnt/β-catenin pathway

OBJECTIVE

The purpose of this study was to explore the function of circular ribonucleic acid (circRNA) zinc finger protein 292 (ZNF292) in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

The expression of circRNA ZNF292 in Huh-7 cells was knocked down by small interfering RNAs (siRNAs), and the effect of circRNA ZNF292 knockdown on the proliferation of Huh-7 cells was analyzed by Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Then, flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) were adopted to analyze the impacts of circRNA ZNF292 knockdown on the cycle distribution and apoptosis of Huh-7 cells. Besides, the influences of circRNA ZNF292 knockdown on Wnt/β-catenin signaling pathway and its downstream molecules were detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting.

RESULTS

Compared with those in siRNA-normal control (NC) group, the proliferation of Huh-7 cells was significantly inhibited and their cloning ability was remarkably weakened (p<0.05), the proportion of cells in S phase was decreased while that in G1 phase was increased (p<0.05), the apoptosis rate of Huh-7 cells was higher and the number of apoptosis was larger in siRNA-2# knockdown group (p<0.05). Besides, in Huh-7 cells with circRNA ZNF292 knockdown, the expressions of Axin, β-catenin, phosphorylated signal transducer and activator of transcription 3 (p-STAT3), p-STAT5, Cyclin A and Cyclin-dependent kinase 2 (CDK2) were down-regulated, while the expressions of STAT3 and STAT5 did not change remarkably.

CONCLUSIONS

Knock downing circRNA ZNF292 leads to cell cycle arrest in G1 phase, thus suppressing cell proliferation and promoting cell apoptosis. The regulatory mechanism of circRNA ZNF292 may involve the regulation of cell cycle and related genes.

MiR-429-5p attenuates the migration and invasion of malignant melanoma by targeting LIMK1

OBJECTIVE

To investigate the potential effects of microRNA-429-5p (miR-429-5p) on the development of malignant melanoma (MM) and the relevant mechanism.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to detect the differential expression of miR-429-5p in MM tissues. The relationship between miR-429-5p expression and clinical pathological data of MM patients was analyzed. LIM kinase 1 (LIMK1) was verified as a downstream target of miR-429-5p by online prediction software, and the interaction between LIMK1 and miR-429-5p was verified by Dual-Luciferase reporter assay.

RESULTS

Compared with normal skin tissues, miR-429-5p was downregulated in MM tissues. MiR-429-5p expression was correlated with tumor size and stage of MM. Upregulation of miR-429-5p significantly inhibited protein expression of LIMK1 and reduced migration and invasion ability of MM cells. LIMK1 was involved in MM progression regulated by miR-429-5p.

CONCLUSIONS

MiR-429-5p attenuates migration and invasion in MM by targeting LIMK1. Hence, miR-429-5p/LIMK1 axis might be a potential therapeutic target for the treatment of MM.

Effects of non-drug interventions on depression, anxiety and sleep in COVID-19 patients: a systematic review and meta-analysis

OBJECTIVE

Patients with Coronavirus Disease 2019 (COVID-19) suffer from anxiety, depression and sleep disorders due to isolation treatment, among other reasons. Whether non-drug interventions can be alternative therapies for COVID-19 patients with anxiety, depression and sleep disorders is controversial. Therefore, we conducted a meta-analysis and systematic review to evaluate the effects of non-drug interventions on anxiety, depression and sleep in patients with COVID-19 to provide guidance for clinical application.

MATERIALS AND METHODS

We searched the following databases for randomized controlled trials (RCTs) from December 2019 to July 2020: China Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), Chongqing VIP Chinese Science and Technology Periodical Database (VIP), Wanfang, Cochrane Library, Web of Science, PubMed, MEDLINE and Embase. Two investigators independently screened the literature according to the inclusion and exclusion criteria, extracted data and evaluated the risk of bias in the included studies. Meta-analysis was performed using RevMan5.3 software.

RESULTS

A total of 5 articles with 768 subjects were included. Meta-analysis results indicated that non-drug interventions can reduce anxiety [SMD=-1.40, 95% CI (-1.62, -1.17), p<0.00001] and depression [SMD=-1.22, 95% CI (-2.01, -0.43), p=0.002] scores in patients with COVID-19. Descriptive analysis indicated that non-drug interventions can improve the sleep status of COVID-19 patients. Sensitivity analysis indicated that the meta-analysis results were stable. Egger's test and Begg's test showed no publication bias.

CONCLUSIONS

This meta-analysis found that non-drug interventions can reduce the anxiety and depression scores of patients with COVID-19. Due to the limitations of this study, more high-quality studies are needed to verify the findings, especially the effect of non-drug interventions on improving the sleep status of COVID-19 patients.

CTRP3 protects hippocampal neurons from oxygen-glucose deprivation-induced injury through the AMPK/Nrf2/ARE pathway

OBJECTIVE

C1q/TNF-related protein 3 (CTRP3), a member of CTRP family, has been found to have neuroprotective effect. In the current study, we investigated the protective role of CTRP3 in hippocampal neurons exposed to oxygen-glucose deprivation/reperfusion (OGD/R).

MATERIALS AND METHODS

The mRNA and protein levels of CTRP3 in OGD/R-stimulated hippocampal neurons were measured using qRT-PCR and western blot analysis, respectively. CCK-8 assay was performed to assess cell viability. ROS production was measured using the fluorescence probe 2',7'-dichlorofluorescein diacetate (H₂DCFDA). The activities of SOD and GPx were determined using ELISA. Cell apoptosis was assessed. Luciferase reporter assay was carried out to assess the activation of ARE). The levels of p-AMPK and Nrf2 were measured using western blot.

RESULTS

Our results showed that the expression of CTRP3 was significantly downregulated in hippocampal neuronal cells exposed to OGD/R. Overexpression of CTRP3 improved cell viability of OGD/R-induced hippocampal neurons. In addition, overexpression of CTRP3 attenuated the OGD/R-caused oxidative stress with decreased ROS production and increased activities of SOD and GPx. Moreover, CTRP3 caused a significant increase in bcl-2 expression and decreases in bax expression and caspase-3 activity. Furthermore, CTRP3 overexpression significantly upregulated the levels of p-AMPK and Nrf2, as well induced the activation of ARE in OGD-R-induced hippocampal neurons. CTRP3 upregulated the mRNA expression levels of HO-1, NQO-1 and GPx-3. Additionally, treatment with the inhibitor of AMPK partially reversed the neuroprotective effect of CTRP3 in OGD/R-exposed neurons.

CONCLUSION

CTRP3 exerted protective effect on OGD/R-induced cerebral injury, which was regulated by AMPK/Nrf2/ARE pathway.

Wolbachia infection in wild mosquitoes (Diptera: Culicidae): implications for transmission modes and host-endosymbiont associations in Singapore

Background

Wolbachia are intracellular bacterial endosymbionts found in most insect lineages. In mosquitoes, the influence of these endosymbionts on host reproduction and arboviral transmission has spurred numerous studies aimed at using Wolbachia infection as a vector control technique. However, there are several knowledge gaps in the literature and little is known about natural Wolbachia infection across species, their transmission modes, or associations between various Wolbachia lineages and their hosts. This study aims to address these gaps by exploring mosquito-Wolbachia associations and their evolutionary implications.

Methods

We conducted tissue-specific polymerase chain reaction screening for Wolbachia infection in the leg, gut and reproductive tissues of wild mosquitoes from Singapore using the Wolbachia surface protein gene (wsp) molecular marker. Mosquito-Wolbachia associations were explored using three methods—tanglegram, distance-based, and event-based methods—and by inferred instances of vertical transmission and host shifts.

Results

Adult mosquitoes (271 specimens) representing 14 genera and 40 species were screened for Wolbachia. Overall, 21 species (51.2%) were found positive for Wolbachia, including five in the genus Aedes and five in the genus Culex. To our knowledge, Wolbachia infections have not been previously reported in seven of these 21 species: Aedes nr. fumidus, Aedes annandalei, Uranotaenia obscura, Uranotaenia trilineata, Verrallina butleri, Verrallina sp. and Zeugnomyia gracilis. Wolbachia were predominantly detected in the reproductive tissues, which is an indication of vertical transmission. However, Wolbachia infection rates varied widely within a mosquito host species. There was no clear signal of cophylogeny between the mosquito hosts and the 12 putative Wolbachia strains observed in this study. Host shift events were also observed.

Conclusions

Our results suggest that the mosquito-Wolbachia relationship is complex and that combinations of transmission modes and multiple evolutionary events likely explain the observed distribution of Wolbachia diversity across mosquito hosts. These findings have implications for a better understanding of the diversity and ecology of Wolbachia and for their utility as biocontrol agents.

[Predictive value of two-dimentional shear wave elastography in posthepatoectomy liver failure]

Objective: To investigate the value of two-dimensional shear wave elastography (2D SWE) combined with clinical biochemical data in predicting posthepatoectomy liver failure (PHLF) in patients with hepatocellular carcinoma (HCC). Methods: A total of 274 HCC patients who underwent hepatectomy in Zhongshan Hospital Fudan University from January 2015 to January 2016 were retrospectively collected, including 235 males and 39 females, age 19-80 (56±11) years. All patients were confirmed to be HCC by postoperative pathology. The preoperative 2D SWE examination, laboratory examination results and intraoperative indicators were analyzed. According to the occurrence of PHLF after surgery, single factor analysis and multiple logistic regression analysis were performed on the above indicators to obtain a binary logistic regression model, and evaluate the diagnostic effect of the model on PHLF. In addition, 103 HCC patients from October 2019 to January 2020 were retrospectively collected as an external validation set, including 89 males and 14 females, age 23-80 (55±11) years old. Results: The liver stiffness measurement (LSM) obtained from 2D SWE, INR and Laminin (LN) were independent predictors of PHLF. The formula of prediction model PM=-15.451+0.095×LSM+11.7×INR+0.012×LN was obtained by combining above three factors. The area under the curve (AUC) of PHLF was 0.82, which was higher than that of end-stage liver disease model (MELD) score and Child-Pugh grading diagnosis of PHLF. The AUC of PHLF predicted by PM in the external validation group was 0.81. Conclusion: 2D SWE is helpful for clinicians to evaluate liver reserve function preoperatively and to predict the occurrence of PHLF in patients with HCC.

UPF1 alleviates the progression of glioma via targeting lncRNA CYTOR

OBJECTIVE

To uncover the role of UPF1 in alleviating the progression of glioma via targeting long non-coding RNA (lncRNA) CYTOR and underlying mechanism.

PATIENTS AND METHODS

A total of 30 glioma tissues surgically resected from glioma patients and 30 brain tissues were collected from brain trauma patients undergoing craniotomy during the same period. Relative levels of UPF1 and CYTOR in collected tissues were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Correlation between levels of UPF1 and CYTOR in glioma tissues was assessed, and the regulatory effects of UPF1/CYTOR on proliferative and invasive abilities in U87 and LN229 cells were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and transwell assay, respectively. In addition, the interaction between UPF1 and CYTOR was explored by RIP (RNA-Binding Protein Immunoprecipitation) assay. Through Actinomycin D treatment in U87 and LN229 cells, RNA stability of CYTOR influenced by UPF1 was determined. Finally, rescue experiments were conducted to ascertain the involvement of CYTOR in UPF1-regulated progression of glioma.

RESULTS

UPF1 was downregulated in glioma tissues and cells. A lower level of UPF1 was observed in glioma tissues in the more advanced stage with a larger tumor size. Besides, the overexpression of UPF1 markedly suppressed proliferation and invasion abilities of U87 and LN229 cells, and CYTOR was upregulated in glioma tissues and cells, which was negatively correlated with UPF1 level. Moreover, the overexpression of UPF1 decreased the half-life of CYTOR in glioma cells. Furthermore, the RIP assay confirmed the interaction between UPF1 and CYTOR. Rescue experiments finally confirmed that the overexpression of CYTOR partially reversed the inhibitory effects of UPF1 on proliferation and invasion abilities in glioma.

CONCLUSIONS

UPF1 is down-regulated in glioma and alleviates the progression of glioma via targeting CYTOR.

[Diagnostic accuracy of liver and spleen stiffness by two dimensional shear wave elastography for portal hypertension in hepatitis B-related cirrhosis]

Objective: To assess the diagnostic accuracy of liver and spleen stiffness measured by two dimensional shear wave elastography (2D-SWE) in hepatitis B-related cirrhosis. Methods: The clinical data of fifty-eight hepatitis B-related cirrhosis patients were collected in Zhongshan Hospital, Fudan University from September 2017 to April 2018. Pearson's correlation analyses were used to assess the relationship between liver/spleen stiffness (L-SWE and S-SWE) and hepatic venous pressure gradient (HVPG), as well as the comparison with serological model. The SWE diagnostic performances of Liver (L-SWE), Spleen (S-SWE) were also evaluated. Results: Of all 58 patients, 47 were found HVPG ≥10 mmHg, diagnosed as clinically significant portal hypertension (CSPH) and severe portal hypertension (SPH), which patients are at increased risk of developing complications. Thirty-four patients were found HVPG≥12 mmHg, diagnosed as SPH, which patients were at increased risk of variceal bleeding. Moderate positive correlation was found between L-SWE and HVPG (r=0.42, P<0.01), and S-SWE were significantly correlated with HVPG (r=0.68, P<0.01), while serological models and HVPG were slightly correlated (r=0.36 and 0.28, all P<0.01). The area under the receiver operating characteristic curves of L-SWE, S-SWE and the combination for CSPH were 0.78, 0.88 and 0.89. When L-SWE was>12.86 kPa or S-SWE was>35.73 kPa, patients were at increased risk of developing complications. The area under the receiver operating characteristic curves for SPH were 0.68, 0.81 and 0.77 and the S-SWE had the highest specificity, so when S-SWE was>41.5 kPa, patients were at increased risk of variceal bleeding. Conclusion: L-SWE and S-SWE are reliable and promising non-invasive parameters to assess CSPH and SPH.

Dietary supplementation with Bacillus subtilis DSM 32315 alters the intestinal microbiota and metabolites in weaned piglets

AIM

The study was conducted to investigate the effects of dietary Bacillus subtilis (BS) DSM 32315 on the intestinal microbiota composition and metabolites of weaned pigs.

METHODS AND RESULTS

Sixty-four piglets were allocated to two groups (control and BS), each group including eight replicates with four piglets. Dietary BS DSM 32315 increased (P < 0·05) the abundances of jejunal Leucobacter and Cupriavidus, ileal Thermus, Coprococcus and Bifidobacterium, as well as colonic Succiniclasticum; and increased the concentrations of ileal straight-chain fatty acids, colonic propionate, branched-chain fatty acids (BCFAs), and tyramine, but decreased (P < .05) the colonic indole concentration. The ileal and colonic microbial community structure tended to cluster into two groups. LEfSe analysis identified five microbial biomarkers in jejunum and eight biomarkers in ileum in the BS group, and three biomarkers in colon in the control group. The ileal Bifidobacterium abundance was positively correlated (P < 0·05) with isovalerate concentration, while the colonic Actinobacteria and Lactobacillus abundances were negatively correlated (P < 0·05) with indole concentration.

CONCLUSION

These findings suggest that dietary supplementation with BS DSM 32315 could alter the diversity, composition, and metabolites of intestinal microbiota in weaned piglets.

SIGNIFICANCE AND IMPACT OF THE STUDY

Weaned piglets are often accompanied with impaired gastrointestinal tract and intestinal disorder affecting their growth. This study demonstrated that dietary BS DSM 32315 presented a beneficial role in gut health via regulating intestinal microbiota composition and metabolites.

Activation of the STAT1 Pathway Accelerates Periodontitis in Nos3-/- Mice

Early studies on the etiology and pathogenesis of hypertension have shown that it has a considerable association with inflammation and the immune response as well as periodontitis. Clinical studies have also shown that hypertension can promote the periodontal tissue destruction caused by periodontitis. However, the underlying mechanisms remain unclear. This study aimed to explore the possible mechanisms of how hypertension aggravates periodontitis. Treatment with or without the signal transducer and activator of transcription 1 (STAT1) inhibitor fludarabine was performed in an endothelial nitric oxide synthase gene knockout-related (Nos3^-/-) mouse model with the hypertension phenotype of periodontitis induced by bacteria. Micro-computed tomography, immunohistochemistry, Western blot, quantitative reverse transcription polymerase chain reaction, immunofluorescence, and ELISA were performed. We demonstrated that Nos3^-/--related hypertension increases bone resorption and periodontal destruction in periodontitis lesion areas, which can be inhibited by the STAT1 inhibitor. Experimental data also showed that Nos3^-/- significantly increased macrophage infiltration and proinflammatory cytokine expression in the periodontitis lesion area, which is dependent on the angiotensin II-induced STAT1 pathway. Inhibition of STAT1 in vivo can decrease the expression of proinflammatory cytokines and macrophage infiltration. Furthermore, data in this study showed that Nos3^-/--related hypertension further downregulated the STAT3 anti-inflammatory function and its downstream chemokine expression in a STAT1-dependent manner. By applying RAW 264.7 and L929 cell lines and monocytes isolated from Nos3^-/- mice, we confirmed that activation of the STAT1 pathway inhibits STAT3 and its downstream pathway and promotes inflammatory cytokine expression in vitro. Collectively, our current study demonstrated that STAT1 plays an indispensable role in the Nos3^-/--related hypertension with aggravation of periodontitis, suggesting that STAT1 may be a key target for the treatment of periodontitis with hypertension.

Successful resolution of skin ulceration by itraconazole in an immunocompetent elderly patient

A 63-year-old patient was presented with faciocervical erythema and ulcers of 3 months duration. Pathological examination showed infiltration of inflammatory cells. Pathogenic microorganism cultivation was negative. However, empirical therapy with itraconazole proved effective.

Nonlinear plasma wavelength scalings in a laser wakefield accelerator

Laser wakefield acceleration relies on the excitation of a plasma wave due to the ponderomotive force of an intense laser pulse. However, plasma wave trains in the wake of the laser have scarcely been studied directly in experiments. Here we use few-cycle shadowgraphy in conjunction with interferometry to quantify plasma waves excited by the laser within the density range of GeV-scale accelerators, i.e., a few 10^{18}cm^{-3}. While analytical models suggest a clear dependency between the nonlinear plasma wavelength and the peak potential a_{0}, our study shows that the analytical models are only accurate for driver strength a_{0}≲1. Experimental data and systematic particle-in-cell simulations reveal that nonlinear lengthening of the plasma wave train depends not solely on the laser peak intensity but also on the waist of the focal spot.

Impact of Air Pollution and Trans-Boundary Haze on Nation-Wide Emergency Department Visits and Hospital Admissions in Singapore

Introduction: Air pollution is associated with adverse health outcomes. However, its impact on emergency health services is less well understood. We investigated the impact of air pollution on nation-wide emergency department (ED) visits and hospital admissions to public hospitals in Singapore. Materials and Methods: Anonymised administrative and clinical data of all ED visits to public hospitals in Singapore from January 2010 to December 2015 were retrieved and analysed. Primary and secondary outcomes were defined as ED visits and hospital admissions, respectively. Conditional Poisson regression was used to model the effect of Pollutant Standards Index (PSI) on each outcome. Both outcomes were stratified according to subgroups defined a priori based on age, diagnosis, gender, patient acuity and time of day. Results: There were 5,791,945 ED visits, of which 1,552,187 resulted in hospital admissions. No significant association between PSI and total ED visits (Relative risk [RR], 1.002; 99.2% confidence interval [CI], 0.995–1.008; P = 0.509) or hospital admissions (RR, 1.005; 99.2% CI, 0.996–1.014; P = 0.112) was found. However, for every 30-unit increase in PSI, significant increases in ED visits (RR, 1.023; 99.2% CI, 1.011–1.036; P = 1.24 × 10˗6) and hospital admissions (RR, 1.027; 99.2% CI, 1.010–1.043; P = 2.02 × 10˗5) for respiratory conditions were found. Conclusion: Increased PSI was not associated with increase in total ED visits and hospital admissions, but was associated with increased ED visits and hospital admissions for respiratory conditions in Singapore. Key words: Epidemiology, Healthcare utilisation, PSI, Public health, Time series

Expression and distribution of HIF-1α, HIF-2α, VEGF, VEGFR-2 and HIMF in the kidneys of Tibetan sheep, plain sheep and goat

BACKGROUND

The objective of this study was to detect the expression and distribution characteristics of five proteins (the hypoxia-inducible factor 1alpha [HIF-1a], HIF-2a, vascular endothelial growth factor [VEGF], VEGF-2 receptor [VEGFR-2] and hypoxia-induced mitogenic factor [HIMF]) in kidney of Tibetan sheep, plain sheep and goat. The results will provide the basic information for the comparative study of sheep breeds living at different altitudes.

MATERIALS AND METHODS

The kidney tissues were collected from healthy adult Tibetan sheep, plain sheep and goats and made into paraffin sections. Histological characteristics were assessed by haematoxylin and eosin staining. Expressions of HIF-1a, HIF-2a, VEGF, VEGFR-2 and HIMF proteins were measured by immunohistochemical staining.

RESULTS

Immunohistochemistry results showed that the positive expression signals of HIF-1a, HIF-2a, VEGF and VEGFR-2 were detected in epithelial cells of renal tubules and collecting tubules, renal corpuscles in the kidneys of the three sheep breeds. Positive expression signals of HIMF were detected in epithelial cells of proximal tubules and distal tubules in Tibetan sheep and epithelial cells of distal tubules in goat. Immunostaining intensity of HIF-1a, HIF-2a, VEGF and VEGFR-2 proteins in Tibetan sheep was significantly higher than that in both plain sheep and goat (p < 0.05). Immunostaining intensity of HIMF in Tibetan sheep was higher than goat (p < 0.05). Positive expression signals of HIMF were not detected in plain sheep.

CONCLUSIONS

The expression and distribution characteristics of HIF-1a, HIF-2a, VEGF, VEGFR-2 and HIMF in the studied kidney tissues suggested that these proteins may be related to the physiological regulation of Tibetan sheep kidney in hypoxia environment, and therefore might be important regulating proteins for Tibetan sheep to adapt to high altitude hypoxia environment.

Impact of Air Pollution and Trans-Boundary Haze on Nation-Wide Emergency Department Visits and Hospital Admissions in Singapore

INTRODUCTION

Air pollution is associated with adverse health outcomes. However, its impact on emergency health services is less well understood. We investigated the impact of air pollution on nation-wide emergency department (ED) visits and hospital admissions to public hospitals in Singapore.

MATERIALS AND METHODS

Anonymised administrative and clinical data of all ED visits to public hospitals in Singapore from January 2010 to December 2015 were retrieved and analysed. Primary and secondary outcomes were defined as ED visits and hospital admissions, respectively. Conditional Poisson regression was used to model the effect of Pollutant Standards Index (PSI) on each outcome. Both outcomes were stratified according to subgroups defined a priori based on age, diagnosis, gender, patient acuity and time of day.

RESULTS

There were 5,791,945 ED visits, of which 1,552,187 resulted in hospital admissions. No significant association between PSI and total ED visits (Relative risk [RR], 1.002; 99.2% confidence interval [CI], 0.995-1.008; P = 0.509) or hospital admissions (RR, 1.005; 99.2% CI, 0.996-1.014; P = 0.112) was found. However, for every 30-unit increase in PSI, significant increases in ED visits (RR, 1.023; 99.2% CI, 1.011-1.036; P = 1.24 × 10^-6 ) and hospital admissions (RR, 1.027; 99.2% CI, 1.010-1.043; P = 2.02 × 10^-5 ) for respiratory conditions were found.

CONCLUSION

Increased PSI was not associated with increase in total ED visits and hospital admissions, but was associated with increased ED visits and hospital admissions for respiratory conditions in Singapore.

P6215Limited functional capacity and physical activity associated with patient withdrawals from cardiac rehabilitation

Background

Cardiac rehabilitation (CR) assists patients with cardiovascular disease (CVD) in improving physical activity and effectively managing their health conditions. With numerous clinical benefits including reduced risks of mortality (by 25%) and all-cause hospitalizations (by 18% - 25%), CR has been strongly recommended by evidence-based clinical guidelines for secondary prevention of CVD. However, many CR participant withdraw and hence fail to fully benefit from their CR programme. To address this issue, knowledge on risk stratification of patients' characteristics to appropriate CR care pathways is important.

Purpose

The purpose of this study is to identify clinical baseline characteristics associated with patients who withdraw from a CR programme.

Methods

We retrospectively analysed patients who participated in the centre-based CR programmes of a research study in Queensland, Australia. The CR programmes provided structured sessions (training and education) once or twice a week for six weeks in community care centres. We compared the patients who withdrew from their CR programme (Group-W) with those who did not withdraw (or simply completion) (Group-C). Withdrawal was defined as discontinuing within the first four weeks of the CR programme. In the comparison, the one-way analysis of variance (ANOVA) and Fisher's exact test were used for analysing age and sex respectively. The analysis of covariance (ANCOVA) with an adjustment for age and sex was used for the body mass index (BMI), six-minute walk test (6WMT), and health-related quality of life (HeartQoL, ESC 2012), comprising physical (HeartQoL-Phy), emotional (HeartQoL-Emo), and global (HeartQoL-Glo) subscales. The study was approved by the Human Research Ethics Committee (Reference: HREC/16/QPAH/636).

Results

From Dec 2016 to Dec 2017, 600 outpatients with CVD were consented, and enrolled in the study. Seventy participants withdrew. Between the two groups (Group-W vs Group-C), no significant differences were found in age (64±12 years vs 65±10 years; p=0.4221), sex (Female, 31% vs 25%; p=0.2461) and BMI (30.5±6.2 vs 30.1±11.2; p=0.8211). The 6MWT distance was significantly lower in Group-W than Group-C (346±103 m vs 394±92 m; p=0.001). Significantly lower scores of HeartQoL-Phy (1.66±0.86 vs 1.93±0.74; p=0.0072) and HeartQoL-Glo scores (1.80±0.78 vs 2.02±0.67; p=0.0205) were found in Group-W. HeartQoL-Emo scores were lower in Group-W but the difference was not significant (2.19±0.73 vs 2.28±0.72; p=0.4550).

Conclusions

The levels of functional capacity measured by 6MWT and physical activity related quality of life were found to be significantly lower in withdrawal patients than those who completed their CR programme. The finding indicates that new care strategies, especially for patients with limited functional capacity and physical activity, are needed to improve the adherence and effectiveness of CR intervention in future studies.

Acknowledgement/Funding

CSIRO and Metro South Health

Effects of bisphenol A exposure on DNA integrity and protamination of mouse spermatozoa

BACKGROUND

Bisphenol A is widely used in the manufacture of polycarbonate plastics and has caused increasing concern over its potential adverse impacts on spermatogenesis. However, the effect of bisphenol A on spermiogenesis is yet to be explored.

OBJECTIVES

To evaluate whether bisphenol A has adverse effects on DNA integrity and protamination of spermatogenic cell.

MATERIALS AND METHODS

Newborn male mice were subcutaneously injected with bisphenol A (0.1, 5 mg/kg body weight, n = 15) or coin oil (control group, n = 20) daily from post-natal day 1 until 35. At post-natal day 70, epididymis caudal spermatozoa and testes were collected. Sperm count, sperm motility, and sperm morphology were analyzed. The sperm chromatin structure assay was performed to examine the sperm DNA fragmentation. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method was used to assess apoptosis of spermatogenic cells. The ultrastructural features of testicular sections were examined under a transmission electron microscope. Western blot and RT-PCR were used to detect the expression levels of transition protein (Tnp) 1 and Tnp2, protamine (Prm) 1 and Prm2 protein, and mRNA in mice testes.

RESULTS

Bisphenol A significantly reduced sperm counts, impaired sperm motility, and increased the percentage of malformed spermatozoa. Poor sperm chromatin integrity and increased TUNEL-positive spermatogenic cells were also observed in mice exposed to bisphenol A. Ultrastructural analysis of testes showed that bisphenol A exposure caused incomplete chromatin condensation, retention of residual cytoplasm, and abnormal acrosome formation. In addition, the relative expression levels of Tnp2 and Prm2 in mice testes decreased significantly in bisphenol A groups.

DISCUSSION AND CONCLUSION

Our findings identified that neonatal bisphenol A exposure may negatively contribute to the sperm quality in adult mice. Mechanistically, we showed that bisphenol A reduced sperm chromatin integrity along with increased DNA damage, which may be due to poor protamination of spermatozoa.