Novel alternative tools for metastatic pheochromocytomas/paragangliomas prediction

OBJECTIVE

The existing prediction models for metastasis in pheochromocytomas/paragangliomas (PPGLs) showed high heterogeneity in different centers. Therefore, this study aimed to establish new prediction models integrating multiple variables based on different algorithms.

DESIGN AND METHODS

Data of patients with PPGLs undergoing surgical resection at the Peking Union Medical College Hospital from 2007 to 2022 were collected retrospectively. Patients were randomly divided into the training and testing sets in a ratio of 7:3. Subsequently, decision trees, random forest, and logistic models were constructed for metastasis prediction with the training set and Cox models for metastasis-free survival (MFS) prediction with the total population. Additionally, Ki-67 index and tumor size were transformed into categorical variables for adjusting models. The testing set was used to assess the discrimination and calibration of models and the optimal models were visualized as nomograms. Clinical characteristics and MFS were compared between patients with and without risk factors.

RESULTS

A total of 198 patients with 59 cases of metastasis were included and classified into the training set (n = 138) and testing set (n = 60). Among all models, the logistic regression model showed the best discrimination for metastasis prediction with an AUC of 0.891 (95% CI, 0.793-0.990), integrating SDHB germline mutations [OR: 96.72 (95% CI, 16.61-940.79)], S-100 (-) [OR: 11.22 (95% CI, 3.04-58.51)], ATRX (-) [OR: 8.42 (95% CI, 2.73-29.24)] and Ki-67 ≥ 3% [OR: 7.98 (95% CI, 2.27-32.24)] evaluated through immunohistochemistry (IHC), and tumor size ≥ 5 cm [OR: 4.59 (95% CI, 1.34-19.13)]. The multivariate Cox model including the above risk factors also showed a high C-index of 0.860 (95% CI, 0.810-0.911) in predicting MFS after surgery. Furthermore, patients with the above risk factors showed a significantly poorer MFS (P ≤ 0.001).

CONCLUSIONS

Models established in this study provided alternative and reliable tools for clinicians to predict PPGLs patients' metastasis and MFS. More importantly, this study revealed for the first time that IHC of ATRX could act as an independent predictor of metastasis in PPGLs.

The Impact of Testosterone on Alzheimer's Disease Are Mediated by Lipid Metabolism and Obesity: A Mendelian Randomization Study

BACKGROUND

To investigate the causal relationship between testosterone (BT) levels and Alzheimer's disease (AD) risk and to quantify the role of obesity and lipid metabolism as potential mediators.

METHODS

We used a two-sample, two-step MR to determine:1) the causal effect of BT levels on AD; 2) the causal effect of two lipid metabolites, obesity and LDLc on AD; and 3) the mediating effects of these metabolites. Pooled data for BT levels and lipid metabolism were obtained from the UK Biobank. AD data were obtained from the Alzheimer's Disease Project International Genomics Consortium, FinnGen Consortium, and UK Biobank study. Effect estimates from external genome-wide association study (GWAS) pooled statistics were obtained using inverse variance-weighted (IVW) MR analysis.

RESULTS

Higher levels of BT were associated with a reduced risk of AD (odds ratio [OR] 0.9992, 95% CI 0.9985-0.9998, P = 0.019), and there was a negative correlation with LDLc (OR 0.9208, 95% CI 0.8569-0.9895, P = 0.024) and obesity class 2 (OC2) (OR 0.7445, 95% CI 0.5873-0.9437, P = 0.014). Conversely, there was a positive correlation between LDLc (OR 1.0014, 95% CI 1.0000-1.0029, P = 0.043) and OC2 (OR 1.0005, 95% CI 1.0001-1.0009, P = 0.003) and AD. Mediation analysis showed that the indirect effect of BT levels on AD was achieved through LDLc and OC2, which accounted for 17% and 17% of the total effect, respectively.

CONCLUSION

Our study identified a causal role of BT levels in LDLc and OC2. BT levels may affect AD through LDLc and OC2 metabolic processes.

Evolution and transmission of antibiotic resistance is driven by Beijing lineage Mycobacterium tuberculosis in Vietnam

IMPORTANCE

Drug-resistant tuberculosis (TB) infection is a growing and potent concern, and combating it will be necessary to achieve the WHO's goal of a 95% reduction in TB deaths by 2035. While prior studies have explored the evolution and spread of drug resistance, we still lack a clear understanding of the fitness costs (if any) imposed by resistance-conferring mutations and the role that Mtb genetic lineage plays in determining the likelihood of resistance evolution. This study offers insight into these questions by assessing the dynamics of resistance evolution in a high-burden Southeast Asian setting with a diverse lineage composition. It demonstrates that there are clear lineage-specific differences in the dynamics of resistance acquisition and transmission and shows that different lineages evolve resistance via characteristic mutational pathways.

Causal association between aspirin use and risk of endometrioid carcinoma: a Mendelian randomization study

OBJECTIVE

The aim of the study was to investigate the causal relationship between aspirin use and the risk of endometrial endometrioid cancer (EEC) using two-sample Mendelian randomization (TSMR) and multivariable Mendelian randomization (MVMR) study.

MATERIALS AND METHODS

A TSMR analysis was conducted to estimate the potential causal relationship between aspirin use and the risk of EEC using genome-wide data from Genome-wide association study (GWAS). The causal association between aspirin use and EEC was further analyzed by MVMR analysis after adjusting for various factors such as obesity, hypertension, diabetes, and infertility. The single nucleotide polymorphism (SNP) data associated with aspirin use and EEC was obtained from the GWAS catalog database.

RESULTS

A total of six SNPs were included as instrumental variables in TSMR, which showed that taking aspirin reduced the risk of EEC [OR = 0.02, 95% CI = 0-0.28, p = 0.005, inverse variance weighted (IVW) method]. Besides, the results of the weighted median (WME) method, weighted mode, and simple mode were consistent with the results shown by the IVW method. After further using the MVMR method, the causal association of aspirin use and prevention of EEC onset remained significant after adjusting for the effects of obesity, hypertension, and diabetes (OR = 0.076, 95% CI = 0.007-0.793, p = 0.031). Sensitivity analyses, including heterogeneity, horizontal multiplicity, and leave-one-out tests, showed the reliability of the instrumental variables, proving that the results were reliable and not significantly biased.

CONCLUSIONS

Taking aspirin can reduce the risk of EEC morbidity, and it is expected to be of great significance for the early prevention and treatment of endometrial cancer by exploring the biological mechanism of aspirin on endometrioid cancer at a deeper level.

[Protective effect of recombinant Schistosoma japonicum cystatin against acute kidney injury associated with acute liver failure in mice]

OBJECTIVE

To evaluate the protective effect of recombinant Schistosoma japonicum cystatin (rSj-Cys) against acute kidney injury induced by acute liver failure and unravel the underlying mechanism, so as to provide insights into the clinical therapy of acute kidney injury.

METHODS

Twenty-four male C57BL/6J mice at ages of 6 to 8 weeks were randomly divided into the normal control group, rSj-Cys control group, lipopolysaccharide (LPS)/D-galactosamine (D-GaIN) model group and LPS/D-GaIN + rSj-Cys treatment group, of 6 mice each group. Mice in the LPS/D-GaIN group and LPS/D-GaIN + rSj-Cys group were intraperitoneally injected with LPS (10 μg/kg) and D-GaIN (700 mg/kg), and mice in the LPS/D-GaIN + rSj-Cys group were additionally administered with rSj-Cys (1.25 mg/kg) by intraperitoneal injection 30 min post-modeling, while mice in the rSj-Cys group were intraperitoneally injected with rSj-Cys (1.25 mg/kg), and mice in the normal control group were injected with the normal volume of PBS. All mice were sacrificed 6 h post-modeling, and mouse serum and kidney samples were collected. Serum creatinine (Cr) and urea nitrogen (BUN) levels were measured, and the pathological changes of mouse kidney specimens were examined using hematoxylin-eosin (HE) staining. Serum tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels were detected using enzyme-linked immunosorbent assay (ELISA), and the expression of inflammatory factors and pyroptosis-related proteins was quantified in mouse kidney specimens using immunohistochemistry. In addition, the expression of pyroptosis-related proteins and nuclear factor-kappa B (NF-κB) signaling pathway-associated proteins was determined in mouse kidney specimens using Western blotting assay.

RESULTS

HE staining showed no remarkable abnormality in the mouse kidney structure in the normal control group and the rSj-Cys control group, and renal tubular injury was found in LPS/D-GaIN group, while the renal tubular injury was alleviated in LPS/D-GaIN+rSj-Cys treatment group. There were significant differences in serum levels of Cr (F = 46.33, P < 0.001), BUN (F = 128.60, P < 0.001), TNF-α (F = 102.00, P < 0.001) and IL-6 (F = 202.10, P < 0.001) among the four groups, and lower serum Cr [(85.35 ± 32.05) μmol/L], BUN [(11.90 ± 2.76) mmol/L], TNF-α [(158.27 ± 15.83) pg/mL] and IL-6 levels [(56.72 ± 4.37) pg/mL] were detected in the in LPS/D-GaIN + rSj-Cys group than in the LPS/D-GaIN group (all P values < 0.01). Immunohistochemical staining detected significant differences in TNF-α (F = 24.16, P < 0.001) and IL-10 (F = 15.07, P < 0.01) expression among the four groups, and lower TNF-α [(106.50 ± 16.57)%] and higher IL-10 expression [(91.83 ± 5.23)%] was detected in the LPS/D-GaIN + rSj-Cys group than in the LPS/D-GaIN group (both P values < 0.01). Western blotting and immunohistochemistry detected significant differences in the protein expression of pyroptosis-related proteins NOD-like receptor thermal protein domain associated protein 3 (NLRP3) (F = 24.57 and 30.72, both P values < 0.001), IL-1β (F = 19.24 and 22.59, both P values < 0.001) and IL-18 (F = 16.60 and 19.30, both P values < 0.001) in kidney samples among the four groups, and lower NLRP3, IL-1β and IL-18 expression was quantified in the LPS/D-GaIN + rSj-Cys treatment group than in the LPS/D-GaIN group (P values < 0.05). In addition, there were significant differences in the protein expression of NF-κB signaling pathway-associated proteins p-NF-κB p-P65/NF-κB p65 (F = 71.88, P < 0.001), Toll-like receptor (TLR)-4 (F = 45.49, P < 0.001) and p-IκB/IκB (F = 60.87, P < 0.001) in mouse kidney samples among the four groups, and lower expression of three NF-κB signaling pathway-associated proteins was determined in the LPS/D-GaIN + rSj-Cys treatment group than in the LPS/D-GaIN group (all P values < 0.01).

CONCLUSIONS

rSj-Cys may present a protective effect against acute kidney injury caused by acute liver failure through inhibiting inflammation and pyroptosis and downregulating the NF-κB signaling pathway.

Design and quality control of large-scale two-sample Mendelian randomization studies

Background

Mendelian randomization (MR) studies are susceptible to metadata errors (e.g. incorrect specification of the effect allele column) and other analytical issues that can introduce substantial bias into analyses. We developed a quality control (QC) pipeline for the Fatty Acids in Cancer Mendelian Randomization Collaboration (FAMRC) that can be used to identify and correct for such errors.

Methods

We collated summary association statistics from fatty acid and cancer genome-wide association studies (GWAS) and subjected the collated data to a comprehensive QC pipeline. We identified metadata errors through comparison of study-specific statistics to external reference data sets (the National Human Genome Research Institute-European Bioinformatics Institute GWAS catalogue and 1000 genome super populations) and other analytical issues through comparison of reported to expected genetic effect sizes. Comparisons were based on three sets of genetic variants: (i) GWAS hits for fatty acids, (ii) GWAS hits for cancer and (iii) a 1000 genomes reference set.

Results

We collated summary data from 6 fatty acid and 54 cancer GWAS. Metadata errors and analytical issues with the potential to introduce substantial bias were identified in seven studies (11.6%). After resolving metadata errors and analytical issues, we created a data set of 219 842 genetic associations with 90 cancer types, generated in analyses of 566 665 cancer cases and 1 622 374 controls.

Conclusions

In this large MR collaboration, 11.6% of included studies were affected by a substantial metadata error or analytical issue. By increasing the integrity of collated summary data prior to their analysis, our protocol can be used to increase the reliability of downstream MR analyses. Our pipeline is available to other researchers via the CheckSumStats package (https://github.com/MRCIEU/CheckSumStats).

Disruption of Aldehyde Dehydrogenase 2 protects against bacterial infection

The ALDH2*2 (rs671) allele is one of the most common genetic mutations in humans, yet the positive evolutionary selective pressure to maintain this mutation is unknown, despite its association with adverse health outcomes. ALDH2 is responsible for the detoxification of metabolically produced aldehydes, including lipid-peroxidation end products derived from inflammation. Here, we demonstrate that host-derived aldehydes 4-hydroxynonenal (4HNE), malondialdehyde (MDA), and formaldehyde (FA), all of which are metabolized by ALDH2, are directly toxic to the bacterial pathogens Mycobacterium tuberculosis and Francisella tularensis at physiological levels. We find that Aldh2 expression in macrophages is decreased upon immune stimulation, and that bone marrow-derived macrophages from Aldh2 -/- mice contain elevated aldehydes relative to wild-type mice. Macrophages deficient for Aldh2 exhibited enhanced control of Francisella infection. Finally , mice lacking Aldh2 demonstrated increased resistance to pulmonary infection by M. tuberculosis , including in a hypersusceptible model of tuberculosis, and were also resistant to Francisella infection. We hypothesize that the absence of ALDH2 contributes to the host's ability to control infection by pathogens such as M. tuberculosis and F. tularensis , and that host-derived aldehydes act as antimicrobial factors during intracellular bacterial infections.

One sentence summary

Aldehydes produced by host cells contribute to the control of bacterial infections.

MUC5AC Genetic Variation Is Associated With Tuberculous Meningitis Cerebral Spinal Fluid Cytokine Responses and Mortality

BACKGROUND

The purpose of this study was to assess if single nucleotide polymorphisms (SNPs) in lung mucins MUC5B and MUC5AC are associated with Mycobacterium tuberculosis outcomes.

METHODS

Independent SNPs in MUC5B and MUC5AC (genotyped by Illumina HumanOmniExpress array) were assessed for associations with tumor necrosis factor (TNF) concentrations (measured by immunoassay) in cerebral spinal fluid (CSF) from tuberculous meningitis (TBM) patients. SNPs associated with CSF TNF concentrations were carried forward for analyses of pulmonary and meningeal tuberculosis susceptibility and TBM mortality.

RESULTS

MUC5AC SNP rs28737416 T allele was associated with lower CSF concentrations of TNF (P = 1.8 × 10-8) and IFN-γ (P = 2.3 × 10-6). In an additive genetic model, rs28737416 T/T genotype was associated with higher susceptibility to TBM (odds ratio [OR], 1.24; 95% confidence interval [CI], 1.03-1.49; P = .02), but not pulmonary tuberculosis (OR, 1.11, 95% CI, .98-1.25; P = .10). TBM mortality was higher among participants with the rs28737416 T/T and T/C genotypes (35/119, 30.4%) versus the C/C genotype (11/89, 12.4%; log-rank P = .005) in a Vietnam discovery cohort (n = 210), an independent Vietnam validation cohort (n = 87; 9/87, 19.1% vs 1/20, 2.5%; log-rank P = .02), and an Indonesia validation cohort (n = 468, 127/287, 44.3% vs 65/181, 35.9%; log-rank P = .06).

CONCLUSIONS

MUC5AC variants may contribute to immune changes that influence TBM outcomes.

Improving the solubility of pseudo-hydrophobic Alzheimer's Disease medicinal chemicals through co-crystal formulation

Natural products are ligands and potential inhibitors of Alzheimer's disease (AD) tau. Dihydromyricetin (DHM) is a CNS active natural product. Despite having signature polyphenolic character, DHM is ostensibly hydrophobic owing to intermolecular hydrogen bonds that shield hydrophilic phenols. Our research shows DHM becomes ionized at near-neutral pH allowing formulation of salts with transformed solubility. The MicroED co-crystal structure with trolamine reveals DHM salts as metastable solids with unlocked hydrogen bonding and a thermodynamic bent to solubilize in water. All salt formulations show better inhibitory activity against AD tau than the non-salt form, with efficacies correlating to enhanced solubilities. These results underscore the role of structural chemistry in guiding selection of solubilizing agents for chemical formulation. We propose DHM salts are appropriate formulations for research as dietary supplements to promote healthy aging by combating protein misfolding. Additionally, DHM is a suitable lead for medicinal chemistry and possible development of CNS pharmaceuticals.

Increased BMI and late-life mobility dysfunction; overlap of genetic effects in brain regions

BACKGROUND

How obesity earlier in life impacts upon mobility dysfunctions in late life is not well understood. Pernicious effects of excess weight on the musculoskeletal system and mobility dysfunctions are well-recognized. However, increasingly more data support the link of obesity to overall motor defects that are regulated in the brain.

OBJECTIVES

To assess the causal relationship between body mass index (BMI) at midlife and performance of the Timed Up-and-Go test (TUG) in late life among a population-based longitudinal cohort of Chinese adults living in Singapore.

METHODS

We evaluated genetic predispositions for BMI in 8342 participants who were followed up from measurement of BMI at average 53 years, to TUG test (as a functional mobility measure) 20 years later.

RESULTS

A robust 75.83% of genetically determined BMI effects on late-life TUG scores were mediated through midlife BMI (P_{indirect-effect} = 9.24 × 10^-21). Utilizing Mendelian randomization, we demonstrated a causal effect between BMI and functional mobility in late life (β_IVW = 0.180, P_IVW = 0.001). Secondary gene enrichment evaluations highlighted down-regulation of genes at BMI risk loci that were correlated with poorer functional mobility in the substantia nigra and amygdala regions as compared to all other tissues. These genes also exhibit differential expression patterns during human brain development.

CONCLUSIONS

We report a causal effect of obesity on mobility dysfunction. Our findings highlight potential neuronal dysfunctions in regulating predispositions on the causal pathway from obesity to mobility dysfunction.

The gene LpBCP increased NaHCO3 resistance by enhancing lignin or ROS scavenging in the Nicotiana benthamiana

Lilium pumilum is an excellent wildflower germplasm resource with high resistance to salinity stress. The gene LpBCP plays an important role in salinity tolerance of L. pumilum. Studying the molecular mechanism of salinity resistance in L. pumilum will provide insights into multiple aspects, including breeding better varieties, environmental protection, improving soil conditions, etc. Conventional methods were used to determine different physiological indicators of Nicotiana benthamiana after NaHCO₃ treatment, i.e. chlorophyll content, soluble phenol content and lignin content. RT-qPCR was carried out to find expression of LpBCP in different organs and under abiotic stresses. DAB was used to detect H₂ O₂ in leaves in situ. A yeast two-hybrid system was used to screen for LpBCP interacting proteins. LpBCP was cloned from bulbs of L. pumilum. The highest expression of LpBCP was in roots and bulbs of transgenic plants. LpBCP-overexpressed plants showed less wilting, compared to WT plants. LpBCP transgenic plants have higher chlorophyll, soluble phenol and lignin content, and lower relative conductivity under 500 mM NaHCO₃ stress. In addition, H₂ O₂ scavenging in transgenic plants was much improved, indicating increased resistance to NaHCO₃ stress. Thirteen LpBCP-interacting proteins were screened using the yeast two-hybrid method and five were associated with salt stress. Based on our findings, LPBCP could be a key gene that can be used to improve L. pumilum salt tolerance.

Abstract 2260: Non-alcoholic fatty liver disease polygenic risk score and risk of hepatocellular carcinoma in an East Asian population

Purpose: It is difficult to identify people with non-alcoholic fatty liver disease (NAFLD) who are at high risk for the development of hepatocellular carcinoma (HCC). A polygenic risk score (PRS) for hepatic fat derived from non-Asians has been reported to be associated with HCC risk in European populations. However, population level data of this risk in non-European populations are lacking.

Methods: Utilizing resources from the Singapore Chinese Health Study (SCHS), we examined the relationship between the previously published hepatic fat PRS (HFC-PRS) and HCC risk. We also constructed and evaluated a NAFLD-related PRS (NAFLD-PRS); the final version included SNPs in similar gene regions as the HFC-PRS but weighted by effect estimates for NAFLD among those with East Asian ancestry. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) of HCC incidence with both HFC-PRS and NAFLD-PRS.

Results: The HFC-PRS and NAFLD-PRS were highly correlated (Spearman r = 0.79, P &lt; 0.001). The highest quartiles of both the HFC-PRS and the NAFLD-PRS were associated with significantly increased risk of HCC with HR of 2.39 (95% CI 1.51, 3.78) and 1.77 (95% CI 1.15, 2.73), respectively, compared to their respective lowest quartile.

Conclusion: The HFC-PRS and the NAFLD-PRS may both be useful in stratifying Asian populations according to their risk of HCC. In addition, the association between the NAFLD-PRS, derived from East Asians, and HCC risk suggests a potential causal role for NAFLD in the development of HCC in this population.

Citation Format: Claire E. Thomas, Brenda Diergaarde, Allison L. Kuipers, Jennifer J. Adibi, Hung N. Luu, Xuling Chang, Rajkumar Dorajoo, Chew-Kiat Heng, Chiea-Chuen Khor, Renwei Wang, Aizhen Jin, Woon-Puay Koh, Jian-Min Yuan. Non-alcoholic fatty liver disease polygenic risk score and risk of hepatocellular carcinoma in an East Asian population [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2260.

Interaction between cigarette smoking and genetic polymorphisms on the associations with age of natural menopause and reproductive lifespan: the Singapore Chinese Health Study

STUDY QUESTION

Are there genetic variants that interact with smoking to reduce reproductive lifespan in East-Asian women?

SUMMARY ANSWER

Our study corroborates several recently identified genetic loci associated with reproductive lifespan and highlights specific genetic predispositions that may interact with smoking status to adversely affect reproductive lifespan in East-Asian women.

WHAT IS KNOWN ALREADY

Epidemiological data as well as evaluations on genetic predisposition to smoke indicate on the importance of smoking in adverse effects on reproductive lifespan in women. However, there are no previous smoking and gene interaction studies for reproductive traits in East-Asian women.

STUDY DESIGN, SIZE, DURATION

This population-based prospective cohort study comprised 11 643 East-Asian Chinese women with overlapping genome-wide genotyping and reproductive data.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We performed a genome-wide association study for reproductive lifespan in women (n = 11 643) from the Singapore Chinese Health Study (SCHS) and carried out a genome-wide interaction study to identify loci that interacted with smoking status to affect age of natural menopause and reproductive-time.

MAIN RESULTS AND THE ROLE OF CHANCE

Two known loci associated with menopause, rs113430717 (near HMCES, chromosome 3, Pmeta = 5.72 × 10-15) and rs3020136 (near RAD21, chromosome 8, Pmeta = 1.38 × 10-8) were observed beyond genome-wide levels of association with age at menopause in this study. For reproductive lifespan, the genome-wide association observed at rs79784106 (chromosome 3, Pmeta = 5.05 × 10-12) was in linkage disequilibrium with the menopause lead single-nucleotide polymorphism (SNP) (rs113430717). Four additional loci, first reported to be associated with menopause, were also associated with reproductive lifespan in our study (PAdj between 7.42 × 10-5 to 4.51 × 10-3). A significant interaction was observed between smoking and an East-Asian specific SNP, rs140146885, for reduced reproductive lifespan, per copy of the minor C allele (beta = -1.417 years, Pinteraction = 2.31 × 10-10). This interaction was successfully replicated in additional independent samples (beta = -1.389 years, Pinteraction = 6.78 × 10-3). Another known variant associated with menopause, rs11031006 (near FSHB), was also observed to interact with smoking status to reduce age at menopause in our dataset (beta = -0.450 years, Padj = 0.042).

LIMITATIONS, REASONS FOR CAUTION

The modest sample size of the replication datasets used likely affected the statistical power to firmly replicate all identified novel loci observed in our smoking interaction analyses.

WIDER IMPLICATIONS OF THE FINDINGS

Age of natural menopause and reproductive lifespan have clear genetic predispositions with distinct ethnic differences, and they may be adversely truncated by lifestyle factors such as smoking, which can pose a significant impact on the reproductive lifespan and future health outcomes in women.

STUDY FUNDING/COMPETING INTEREST(S)

The Singapore Chinese Health Study is funded by the National Medical Research Council, Singapore (NMRC/CIRG/1456/2016), National Institutes of Health (R01 CA144034 and UM1 CA182876) and National Research Foundation, Singapore (Project Number 370062002). W.-P.K. is supported by the National Medical Research Council, Singapore (MOH-CSASI19nov-0001). The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication. The authors do not report conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

The association of genetic susceptibility to smoking with cardiovascular disease mortality and the benefits of adhering to a DASH diet: The Singapore Chinese Health Study

BACKGROUND

Understanding the genetic predisposition to cardiovascular disease (CVD) may help to improve clinical intervention strategies. Lifestyle factors, such as diet, may differ among ethnic groups and may, in turn, modify individuals' risks to diseases.

OBJECTIVES

We examined the genetic predisposition to ever smoking in relation to CVD mortality and assessed whether such an association could be modified by dietary intake.

METHODS

A total of 23,760 Chinese adults from the Singapore Chinese Heath Study who were free of cancer and CVD at recruitment (1993-1998) were included in the study. A weighted genetic risk score (wGRS) was calculated to define the genetically determined regular smoking behavior (never or ever). Multivariable-adjusted Cox regression models were used to assess the association between the wGRS and CVD mortality. We also conducted a 1-sample Mendelian randomization analysis for ever smoking and CVD mortality.

RESULTS

Over a mean of 22.6 years of follow-up, 2301 CVD deaths were identified. A genetic predisposition to ever smoking was significantly associated with CVD mortality; the multivariable-adjusted HR of CVD mortality was 1.07 (95% CI: 1.03-1.12), with a per-SD increment in the wGRS. However, the Mendelian randomization analysis did not support a causal relationship between ever smoking and CVD mortality (OR, 1.13; 95% CI: 0.87-1.45). Additionally, the Dietary Approaches to Stop Hypertension (DASH) score significantly modified the association between the smoking wGRS and CVD mortality; the association between a genetic predisposition to smoking and CVD mortality was only observed among individuals with a low DASH score (P-interaction = 0.004).

CONCLUSIONS

A genetic predisposition to smoking was associated with CVD mortality in the Chinese population. In addition, we detected a significant interaction showing higher CVD mortality related to genetically determined smoking among those with lower DASH scores.

NAFLD polygenic risk score and risk of hepatocellular carcinoma in an East Asian population

It is difficult to identify people with nonalcoholic fatty liver disease (NAFLD) who are at high risk for developing hepatocellular carcinoma (HCC). A polygenic risk score (PRS) for hepatic fat (HFC-PRS) derived from non-Asians has been reported to be associated with HCC risk in European populations. However, population-level data of this risk in Asian populations are lacking. Utilizing resources from 24,333 participants of the Singapore Chinese Health Study (SCHS), we examined the relationship between the HFC-PRS and HCC risk. In addition, we constructed and evaluated a NAFLD-related PRS (NAFLD-PRS) with HCC risk in the SCHS. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of HCC incidence with both HFC-PRS and NAFLD-PRS. The HFC-PRS and NAFLD-PRS were highly correlated (Spearman r = 0.79, p < 0.001). The highest quartiles of both the HFC-PRS and the NAFLD-PRS were associated with significantly increased risk of HCC with HR of 2.39 (95% CI 1.51, 3.78) and 1.77 (95% CI 1.15, 2.73), respectively, compared with their respective lowest quartile. Conclusion: The PRS for hepatic fat content or NAFLD may be useful for assessing HCC risk in both Asian and European populations. The findings of this and prior studies support a potential causal role of genetically determined NAFLD in HCC development.

Genetic associations with healthy ageing among Chinese adults

The genetic basis of overall healthy ageing, especially among the East-Asian population is understudied. We conducted a genome-wide association study among 1618 Singapore Chinese elderly participants (65 years or older) ascertained to have aged healthily and compared their genome-wide genotypes to 6221 participants who did not age healthily, after a 20-year follow-up. Two genetic variants were identified (P_Meta < 2.59 × 10^-8) to be associated with healthy aging, including the LRP1B locus previously associated in long-lived individuals without cognitive decline. Our study sheds additional insights on the genetic basis of healthy ageing.

REL and BHLHE40 Variants Are Associated with IL-12 and IL-10 Responses and Tuberculosis Risk

The major human genes regulating Mycobacterium tuberculosis-induced immune responses and tuberculosis (TB) susceptibility are poorly understood. Although IL-12 and IL-10 are critical for TB pathogenesis, the genetic factors that regulate their expression in humans are unknown. CNBP, REL, and BHLHE40 are master regulators of IL-12 and IL-10 signaling. We hypothesized that common variants in CNBP, REL, and BHLHE40 were associated with IL-12 and IL-10 production from dendritic cells, and that these variants also influence adaptive immune responses to bacillus Calmette-Guérin (BCG) vaccination and TB susceptibility. We characterized the association between common variants in CNBP, REL, and BHLHE40, innate immune responses in dendritic cells and monocyte-derived macrophages, BCG-specific T cell responses, and susceptibility to pediatric and adult TB in human populations. BHLHE40 single-nucleotide polymorphism (SNP) rs4496464 was associated with increased BHLHE40 expression in monocyte-derived macrophages and increased IL-10 from peripheral blood dendritic cells and monocyte-derived macrophages after LPS and TB whole-cell lysate stimulation. SNP BHLHE40 rs11130215, in linkage disequilibrium with rs4496464, was associated with increased BCG-specific IL-2+CD4+ T cell responses and decreased risk for pediatric TB in South Africa. SNPs REL rs842634 and rs842618 were associated with increased IL-12 production from dendritic cells, and SNP REL rs842618 was associated with increased risk for TB meningitis. In summary, we found that genetic variations in REL and BHLHE40 are associated with IL-12 and IL-10 cytokine responses and TB clinical outcomes. Common human genetic regulation of well-defined intermediate cellular traits provides insights into mechanisms of TB pathogenesis.

A polygenic risk score improves risk stratification of coronary artery disease: a large-scale prospective Chinese cohort study

Aims

To construct a polygenic risk score (PRS) for coronary artery disease (CAD) and comprehensively evaluate its potential in clinical utility for primary prevention in Chinese populations.

Methods and results

Using meta-analytic approach and large genome-wide association results for CAD and CAD-related traits in East Asians, a PRS comprising 540 genetic variants was developed in a training set of 2800 patients with CAD and 2055 controls, and was further assessed for risk stratification for CAD integrating with the guideline-recommended clinical risk score in large prospective cohorts comprising 41 271 individuals. During a mean follow-up of 13.0 years, 1303 incident CAD cases were identified. Individuals with high PRS (the highest 20%) had about three-fold higher risk of CAD than the lowest 20% (hazard ratio 2.91, 95% confidence interval 2.43–3.49), with the lifetime risk of 15.9 and 5.8%, respectively. The addition of PRS to the clinical risk score yielded a modest yet significant improvement in C-statistic (1%) and net reclassification improvement (3.5%). We observed significant gradients in both 10-year and lifetime risk of CAD according to the PRS within each clinical risk strata. Particularly, when integrating high PRS, intermediate clinical risk individuals with uncertain clinical decision for intervention would reach the risk levels (10-year of 4.6 vs. 4.8%, lifetime of 17.9 vs. 16.6%) of high clinical risk individuals with intermediate (20–80%) PRS.

Conclusion

The PRS could stratify individuals into different trajectories of CAD risk, and further refine risk stratification for CAD within each clinical risk strata, demonstrating a great potential to identify high-risk individuals for targeted intervention in clinical utility.

Lipoprotein(a) as predictor of coronary artery disease and myocardial infarction in a multi-ethnic Asian population

BACKGROUND AND AIMS

The role of Lp(a) in multi-ethnic Asian populations with coronary artery disease (CAD) has not been well established. The aims of this study were (i) to investigate whether Lp(a) is a predictor of CAD, and (ii) amongst patients with CAD, to ascertain whether Lp(a) is a predictor of acute myocardial infarction (AMI) and severity of CAD.

METHODS

We compared three cardiovascular phenotypes from patients recruited at coronary angiography. CAD was defined as ≥50% coronary artery stenosis and subdivided into a group with AMI history (CAD+AMI+) and a group without (CAD+AMI-). Minimal CAD group (CAD-) was defined as normal or <30% coronary artery stenosis and no AMI. The severity of CAD was defined using the modified Gensini score.

RESULTS

We studied 2025 patients comprising 94.5% men and 61.4% of Chinese ethnicity. The median Lp(a) level was highest in CAD+AMI+, followed by CAD+AMI- and CAD- (26.2, 20.1, and 15.8 nmol/L respectively). Similarly, the frequency of patients with Lp(a) ≥120 nmol/L were in the same order (11.8%, 9.1% and 2.4%). Lp(a) levels were highest among Asian Indians, followed by Malays and Chinese patients (p < 0.001). Lp(a) levels and Lp(a) ≥120 nmol/L were significant predictors of CAD (Odds ratio (OR) = 1.12 per 10 nmol/L increment, p < 0.001, and OR = 5.41 p = 0.004 respectively). Among patients with CAD, higher Lp(a) levels were associated with increased AMI risk (OR = 1.02 per 10 nmol/L increment, p = 0.024). Lp(a) ≥120 nmol/L was positively associated with CAD severity (p = 0.020).

CONCLUSIONS

Plasma Lp(a) concentration is a positive predictor of CAD and AMI in a mostly male South East Asian population.

Midlife Leukocyte Telomere Length as an Indicator for Handgrip Strength in Late Life

BACKGROUND

Telomere attrition has been proposed as a hallmark of aging. We previously reported on the association between blood leukocyte telomere length (LTL) at midlife and risk of chronic diseases and mortality.

METHODS

In this study, we investigated the effect of midlife LTL and genetic proxies on 5 markers of aging outcomes, namely handgrip strength, timed up-and-go (TUG), Singapore-modified Mini-Mental State Examination (SM-MMSE) scores, anxiety, and depression indices, measured after a median 20-year follow-up in the Singapore Chinese Health Study (N = 9581).

RESULTS

We observed a significant association between midlife LTL and handgrip strength later in life (p = .004, padjust = .020), as well as a nominal significant association between midlife LTL and TUG later in life (p = .036, padjust = .180). The weighted Genetic Risk Score (wGRS) comprising 15 previously reported LTL reducing loci in East Asians was not significantly associated with handgrip strength. However, results from Structural Equation Modeling showed that the effect of this wGRS on handgrip strength was mediated through LTL (proportion of wGRS effect on handgrip strength mediated through LTL = 33.3%, p = .010).

CONCLUSIONS

Longer midlife LTL was associated with increased handgrip strength later in life.

[Fucoxanthin induces prostate cancer PC-3 cell apoptosis by causing mitochondria dysfunction and oxidative stress]

OBJECTIVE

To investigate the apoptosis- inducing effect of fucoxanthin in human prostate cancer PC-3 cells and the underlying mechanism.

OBJECTIVE

The viability and apoptosis of PC-3 cells treated with fucoxanthin were analyzed using commercial kits, and the mitochondrial membrane potential, mitochondrial morphology and mitochondrial superoxide were detected using fluorescence probe staining. The contents of ATP, H₂O₂, malondialdehyde (MDA), superoxide and the total antioxidant capacity of PC-3 cells were determined. The protein expressions of Bcl-2, Bax and cytochrome c were detected with Western blotting, and the activity of caspase-9 and caspase- 3/7 was detected using corresponding kits.

OBJECTIVE

Fucoxanthin significantly inhibited the viability of PC-3 cells in a time- and dose-dependent manner, and dose-dependently induced apoptosis of the cells (P < 0.05). Fucoxanthin-treated PC-3 cells showed significantly decreased mitochondrial membrane potential, mitochondrial fragmentation and increased superoxide level in the mitochondria (P < 0.05), and these effects of fucoxanthin were dose- dependent. Fucoxanthin dose-dependently decreased ATP level and the total antioxidant capacity of PC-3 cells, increased the contents of H₂O₂, MDA and superoxide (all P < 0.05), enhanced the protein expressions of Bax and cytochrome c in the cytoplasm, and lowered the protein expressions of Bcl-2 and cytochromes in the mitochondria (P < 0.05).

OBJECTIVE

Fucoxanthin induces apoptosis of PC-3 cells by triggering mitochondrial dysfunction to cause oxidative stress and by activating mitochondria-mediated apoptotic signaling pathways, suggesting its potential in prostate cancer treatment.

The association of genetically determined serum glycine with cardiovascular risk in East Asians

BACKGROUND AND AIMS

Glycine is involved in a wide range of metabolic pathways and increased circulating glycine is associated with reduced risk of cardio-metabolic diseases in Europeans but the genetic association between circulating glycine and cardiovascular risk is largely unknown in East Asians.

METHODS AND RESULTS

We conducted a genome-wide association study (GWAS) in Singaporean Chinese participants and investigated if genetically determined serum glycine were associated with incident coronary artery disease (CAD) (711 cases and 1,246 controls), cardiovascular death (1,886 cases and 21,707 controls) and angiographic CAD severity (as determined by the Modified Gensini score, N = 1,138).

CONCLUSION

Our study, a first in East Asians, suggest a protective role of glycine against CAD.

Genome-wide analysis identifies novel susceptibility loci for myocardial infarction

AIMS

While most patients with myocardial infarction (MI) have underlying coronary atherosclerosis, not all patients with coronary artery disease (CAD) develop MI. We sought to address the hypothesis that some of the genetic factors which establish atherosclerosis may be distinct from those that predispose to vulnerable plaques and thrombus formation.

METHODS AND RESULTS

We carried out a genome-wide association study for MI in the UK Biobank (n∼472 000), followed by a meta-analysis with summary statistics from the CARDIoGRAMplusC4D Consortium (n∼167 000). Multiple independent replication analyses and functional approaches were used to prioritize loci and evaluate positional candidate genes. Eight novel regions were identified for MI at the genome wide significance level, of which effect sizes at six loci were more robust for MI than for CAD without the presence of MI. Confirmatory evidence for association of a locus on chromosome 1p21.3 harbouring choline-like transporter 3 (SLC44A3) with MI in the context of CAD, but not with coronary atherosclerosis itself, was obtained in Biobank Japan (n∼165 000) and 16 independent angiography-based cohorts (n∼27 000). Follow-up analyses did not reveal association of the SLC44A3 locus with CAD risk factors, biomarkers of coagulation, other thrombotic diseases, or plasma levels of a broad array of metabolites, including choline, trimethylamine N-oxide, and betaine. However, aortic expression of SLC44A3 was increased in carriers of the MI risk allele at chromosome 1p21.3, increased in ischaemic (vs. non-diseased) coronary arteries, up-regulated in human aortic endothelial cells treated with interleukin-1β (vs. vehicle), and associated with smooth muscle cell migration in vitro.

CONCLUSIONS

A large-scale analysis comprising ∼831 000 subjects revealed novel genetic determinants of MI and implicated SLC44A3 in the pathophysiology of vulnerable plaques.

Low frequency variants associated with leukocyte telomere length in the Singapore Chinese population

The role of low frequency variants associated with telomere length homeostasis in chronic diseases and mortalities is relatively understudied in the East-Asian population. Here we evaluated low frequency variants, including 1,915,154 Asian specific variants, for leukocyte telomere length (LTL) associations among 25,533 Singapore Chinese samples. Three East Asian specific variants in/near POT1, TERF1 and STN1 genes are associated with LTL (Meta-analysis P 2.49×10-14-6.94×10-10). Rs79314063, a missense variant (p.Asp410His) at POT1, shows effect 5.3 fold higher and independent of a previous common index SNP. TERF1 (rs79617270) and STN1 (rs139620151) are linked to LTL-associated common index SNPs at these loci. Rs79617270 is associated with cancer mortality [HR95%CI = 1.544 (1.173, 2.032), PAdj = 0.018] and 4.76% of the association between the rs79617270 and colon cancer is mediated through LTL. Overall, genetically determined LTL is particularly associated with lung adenocarcinoma [HR95%CI = 1.123 (1.051, 1.201), Padj = 0.007]. Ethnicity-specific low frequency variants may affect LTL homeostasis and associate with certain cancers.

Integrating Narcissus-derived galanthamine production into traditional upland farming systems

Alzheimer's disease (AD) is a disorder associated with progressive degeneration of memory and cognitive function. Galantamine is a licenced treatment for AD but supplies of the plant alkaloid that it is produced from, galanthamine, are limited. This three-year system study tested the potential to combine Narcissus-derived galanthamine production with grassland-based ruminant production. Replicate plots of permanent pasture were prepared with and without bulbs of Narcissus pseudonarcissus sown as lines into the sward. Two different fertiliser regimes were imposed. The above-ground green biomass of N. pseudonarcissus was harvested in early spring and the galanthamine yield determined. In the second harvest year a split-plot design was implemented with lines of N. pseudonarcissus cut annually and biennially. All plots were subsequently grazed by ewes and lambs and animal performance recorded. Incorporation of N. pseudonarcissus into grazed permanent pasture had no detrimental effects on the health or performance of the sheep which subsequently grazed the pasture. There was no consistency to the effects of fertiliser rates on galanthamine yields. There was no difference in overall galanthamine yield if N. pseudonarcissus was cut biennially (1.64 vs. 1.75 kg galanthamine/ha for annual combined vs biennial cuts respectively; s.e.d = 0.117 kg galanthamine/ha; ns). This study verified the feasibility of a dual cropping approach to producing plant-derived galanthamine.

[Application of autologous platelet-rich plasma separation in cardiac valve replacement: a random clinical trial]

Objective: To examine the blood protective effect of autologous platelet-rich plasma separation for cardiac valve replacement under cardiopulmonary bypass. Methods: Sixty patients who underwent cardiac valve replacement under cardiopulmonary bypass from August 2018 to May 2019 in Shanghai Chest Hospital, Shanghai Jiao Tong University were randomly divided into control and treatment groups(each 30 cases). There were 33 males and 27 females, aged (52.0±8.4) years (range: 35 to 65 years). Autologous platelet separation was performed in the treatment group after anaesthesia administration and was completed before systemic heparinisation. Platelet separation was not performed in the control group. The thromboelastogram, blood routine, blood coagulation, perioperative fluid infusion, allogeneic blood transfusion, postoperative pleural fluid volume and postoperative fibrinogen were recorded before the operation, and 1 hour and 24 hours post operation. The two groups' data was compared by t test, Kruskal-Wallis test, Mann-Whitney U test or χ(2) test. Repeated measurement analysis of variance was used to compare platelet and coagulation indexes at different times. Results: The perioperative red blood cell transfusion of 0, 1~2, 3~4,>4 units with 6, 11, 1, 12 cases in treatment group and 14, 8, 6, 2 cases in control group (Z=-2.516, P=0.012). The postoperative fibrinogen of 0, 1, 2 units with 19, 2, 9 cases in treat group and 26, 2, 2 cases in control group (Z=-2.190, P=0.029). There was no significant difference in the cost of blood transfusion between the two groups during admission ((1 732±1 275) yuan vs. (1 176±941) yuan; t=-1.570, P=0.125). Conclusion: The use of autologous platelet-rich plasma separation can reduce the amount of allogeneic blood transfusion during valvular surgery under cardiopulmonary bypass.

Understanding the electric and nonelectric field components of the cation effect on the electrochemical CO reduction reaction

Electrolyte cations affect the activity of surface-mediated electrocatalytic reactions; however, understanding the modes of interaction between cations and reaction intermediates remains lacking. We show that larger alkali metal cations (excluding the thickness of the hydration shell) promote the electrochemical CO reduction reaction on polycrystalline Cu surfaces in alkaline electrolytes. Combined reactivity and in situ surface-enhanced spectroscopic investigations show that changes to the interfacial electric field strength cannot solely explain the reactivity trend with cation size, suggesting the presence of a nonelectric field strength component in the cation effect. Spectroscopic investigations with cation chelating agents and organic molecules show that the electric and nonelectric field components of the cation effect could be affected by both cation identity and composition of the electrochemical interface. The interdependent nature of interfacial species indicates that the cation effect should be considered an integral part of the broader effect of composition and structure of the electrochemical interface on electrode-mediated reactions.

Effect of plasma polyunsaturated fatty acid levels on leukocyte telomere lengths in the Singaporean Chinese population

BACKGROUND

Shorter telomere length (TL) has been associated with poor health behaviors, increased risks of chronic diseases and early mortality. Excessive shortening of telomere is a marker of accelerated aging and can be influenced by oxidative stress and nutritional deficiency. Plasma n6:n3 polyunsaturated fatty acid (PUFA) ratio may impact cell aging. Increased dietary intake of marine n-3 PUFA is associated with reduced telomere attrition. However, the effect of plasma PUFA on leukocyte telomere length (LTL) and its interaction with genetic variants are not well established.

METHODS

A nested coronary artery disease (CAD) case-control study comprising 711 cases and 638 controls was conducted within the Singapore Chinese Health Study (SCHS). Samples genotyped with the Illumina ZhongHua-8 array. Plasma n-3 and n-6 PUFA were quantified using mass spectrometry (MS). LTL was measured with quantitative PCR method. Linear regression was used to test the association between PUFA and LTL. The interaction between plasma PUFAs and genetic variants was assessed by introducing an additional term (PUFA×genetic variant) in the regression model. Analysis was carried out in cases and controls separately and subsequently meta-analyzed using the inverse-variance weighted method. We further assessed the association of PUFA and LTL with CAD risk by Cox Proportional-Hazards model and whether the effect of PUFA on CAD was mediated through LTL by using structural equation modeling.

RESULTS

Higher n6:n3 ratio was significantly associated with shorter LTL (p = 0.018) and increased CAD risk (p = 0.005). These associations were mainly driven by elevated plasma total n-3 PUFAs, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (p < 0.05). There was a statistically significant interaction for an intergenic single nucleotide polymorphism (SNP) rs529143 with plasma total n-3 PUFA and DHA on LTL beyond the genome-wide threshold (p < 5 ×  10^- 8). Mediation analysis showed that PUFA and LTL affected CAD risk independently.

CONCLUSIONS

Higher plasma n6:n3 PUFA ratio, and lower EPA and DHA n-3 PUFAs were associated with shorter LTL and increased CAD risk in this Chinese population. Furthermore, genetic variants may modify the effect of PUFAs on LTL. PUFA and LTL had independent effect on CAD risk in our study population.

Propranolol regulates ERK1/2 signaling pathway and promotes chronic wound healing in diabetic rats

OBJECTIVE

This study aimed to investigate if propranolol could regulate ERK1/2 signaling pathway and promote chronic wound healing in diabetic rats.

MATERIALS AND METHODS

Twenty-two rats were used to establish a diabetic chronic wound animal model. They were randomly separated into two groups: the propranolol group and the control group. The propranolol group was treated with propranolol ointment and the control group was treated with propranolol matrix cream to cover the wound surface. The expression of the p-ERK1/2 protein was detected by the Western Blot. RT-qPCR was used to detect the expression of VEGF. The concentrations of IL-6 and TNF-α were detected by ELISA.

RESULTS

The body weight of rats was significantly reduced after type 2 diabetes mellitus modeling. The healing rate of rats in the control group was significantly lower than that in the propranolol group (p<0.05). There was a significant increase in the expression of the p-ERK1/2 protein in the wound tissue of the propranolol group compared with that in the control group, except for the 11th day (p<0.05). The relative expression of Vascular Endothelial Growth Factor (VEGF) in the propranolol group was significantly higher than that in the control group on the 2nd day (p<0.05), while the relative expression of VEGF in the propranolol group was significantly increased on the 11th day after modeling (p<0.05). On the 20th day, the expressions of IL-6 and TNF-α in the propranolol group were significantly higher than those in the control group, and there were significant differences (p<0.05). It was found that the IL-6 and TNF-α expressions in the propranolol group reached the peak on the 11th day and then gradually decreased (p<0.05).

CONCLUSIONS

The results indicated that propranolol can accelerate the healing of diabetic wounds by regulating the expression of VEGF by phosphorylation of ERK1/2 protein, thus promoting chronic wound healing in diabetes.

Interaction between a haptoglobin genetic variant and coronary artery disease (CAD) risk factors on CAD severity in Singaporean Chinese population

Background

Haptoglobin (Hp) is a plasma protein with strong anti‐inflammation and antioxidant activities. Its plasma level is known to be inversely associated with many inflammatory diseases, including cardiovascular diseases. However, the association of HP genetic variants with coronary artery disease (CAD) severity/mortality, and how they interact with common CAD risk factors are largely unknown.

Methods

We conducted the analysis in a Singaporean Chinese CAD population with Gensini severity scores (N = 582) and subsequently evaluated the significant findings in an independent cohort with cardiovascular mortality (excluding stroke) as outcome (917 cases and 19,093 controls). CAD risk factors were ascertained from questionnaires, and stenosis information from medical records. Mortality was identified through linkage with the nationwide registry of births and deaths in Singapore. Linear regression analysis between HP genetic variant (rs217181) and disease outcome were performed. Interaction analyses were performed by introducing an interaction term in the same regression models.

Results

Although rs217181 was not significantly associated with CAD severity and cardiovascular mortality (excluding stroke) in all subjects, when stratified by hypertension status, hypertensive individuals with the minor T allele have more severe CAD (β = 0.073, SE = 0.030, p = 0.015) and non‐hypertensive individuals with the T allele have lower risk for mortality (odds ratio = 0.771 (0.607–0.980), p = 0.033).

Conclusion

HP genetic variant is not associated with CAD severity and mortality in the general population. However, hypertensive individuals with the rs217181 T allele associated with higher Hp levels had more severe CAD while non‐hypertensive individuals with the same allele had lower risk for mortality in the Chinese population.

Influence of roflumilast on sepsis mice through the JAK/STAT signaling pathway

OBJECTIVE

The aim of this study was to explore the influence of roflumilast on sepsis mice through the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway.

MATERIALS AND METHODS

A total of 36 Sprague-Dawley mice were randomly divided into normal group (n=12), model group (n=12) and roflumilast group (n=12). Mice in the normal group were fed normally. However, mice in the model group and roflumilast group were intraperitoneally injected with endotoxin to establish the sepsis mouse model. Furthermore, mice in the model group and roflumilast group were intraperitoneally injected with 0.9% sodium chloride and roflumilast once a day, respectively. After 7 d of intervention, mice were sampled. Lung tissue morphology was observed via hematoxylin-eosin (HE) staining, and the pathological score was given. The protein expression levels of JAK and STAT-3 were detected via Western blotting. The expression levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected via enzyme-linked immunosorbent assay (ELISA). Meanwhile, the mRNA expression levels of JAK, STAT-3, IL-6 and TNF-α were detected via quantitative Polymerase Chain Reaction (qPCR). The number of inflammatory cells in the lavage fluid was counted by a biochemical detector.

RESULTS

The survival rate of mice in the roflumilast group was significantly higher than that of the model group (p<0.05). The results of HE staining revealed that lung tissue morphology in roflumilast group was significantly improved when compared with the model group. Meanwhile, the pathological score in the roflumilast group was significantly lower than that of the model group (p<0.05). Western blotting showed that the protein expression levels of JAK and STAT-3 in the roflumilast group were markedly lower than those of the model group (p<0.05). According to the results of ELISA, the expression levels of IL-6 and TNF-α in the roflumilast group were remarkably lower than the model group (p<0.05). Further qPCR results manifested that the mRNA expression levels of JAK, STAT-3, IL-6 and TNF-α in the roflumilast group were significantly lower than those of the model group (p<0.05). Moreover, the number of neutrophils, monocytes and lymphocytes in the roflumilast group was significantly smaller than the model group.

CONCLUSIONS

Roflumilast can improve lung tissue morphology of sepsis mice by inhibiting the JAK/STAT signaling pathway.

Rapid isolation of non-aflatoxigenic Aspergillus flavus strains

In the present study, a method for screening non-aflatoxigenic Aspergillus flavus in soil samples collected from major peanut-growing regions of China was developed. The single colonies were picked and cultured on Aspergillus flavus and parasiticus agar (AFPA). If the reverse side of the colony on AFPA was orange-coloured, it was considered A. flavus or Aspergillus parasiticus. After the genomic DNA of each strain was extracted, 28S rRNA and calmodulin were amplified and sequenced to determine the species. The key gene, aflR, was amplified and digested via polymerase chain reaction-restriction fragment length polymorphism. The aflatoxigenic A. flavus and the non-aflatoxigenic A. flavus and A. parasiticus were distinguished by enzyme digestion of aflR. 156 strains of A. flavus were screened, which consisted of 135 aflatoxigenic and 21 non-aflatoxigenic strains. The aflatoxin producing ability of each strain was confirmed using solid-state fermentation experiments. Using the method developed in the present study, we confirmed that the non-aflatoxigenic A. flavus strains isolated lost their capacity to produce aflatoxins. Considering there could be some alterations in other functional genes, some non-aflatoxigenic strains could be identified inaccurately as aflatoxigenic strains, although that did not occur in the present study. The growth of non-aflatoxigenic A. flavus was observed, and the most rapidly growing non-aflatoxigenic strain was selected for plate confrontation assays and toxic mixed culture experiments. The inhibition rate of non-aflatoxigenic A. flavus against aflatoxigenic A. flavus was 55.4 and 72.6% in potato dextrose agar (PDA) plate and natural soybean medium, respectively. The screened non-aflatoxigenic A. flavus strains provide a microbial resource for biological control of aflatoxin contamination.

Downregulation of kynureninase restrains cutaneous squamous cell carcinoma proliferation and represses the PI3K/AKT pathway

BACKGROUND

The protein kynureninase (KYNU) has recently been reported to participate in the pathological processes of various diseases.

AIM

To explore the expression and the biological function of KYNU in cutaneous squamous cell carcinoma (cSCC).

METHODS

Expression of KYNU in cSCC cell lines and tissues was firstly evaluated based on the Gene Expression Omnibus and the Oncomine databases. Quantitative reverse transcription-PCR was performed to determine the mRNA expression of KYNU in cSCC cell lines. Small interfering RNA (siRNA) was used for silencing KYNU. The effect of KYNU on the growth and motility of cSCC cells was determined by cell counting kit-8, wound-healing and Transwell assays, and western blotting was used to determine the protein expression of KYNU, AKT, phosphoinositide 3-kinase (PI3K), phosphorylated (p)-AKT and p-PI3K.

RESULTS

KYNU was significantly upregulated in cSCC tissues and cell lines. Knockdown of KYNU using siRNA noticeably suppressed the proliferation, migration and invasion ability of SCL-1 cells (P < 0.01). Western blotting revealed that phosphorylation of AKT and PI3K was markedly inhibited after silencing KYNU. The ratios of p-AKT/AKT and p-PI3K/PI3K were significantly decreased in the si-KYNU group compared with the control group.

CONCLUSION

Depletion of KYNU could inhibit the growth of cSCC cells, possibly through modulating PI3K/AKT pathway. These data indicate that KYNU takes a key part in the malignant progression of cSCC, and could be considered as a promising therapeutic target for cSCC treatment.

Loci for human leukocyte telomere length in the Singaporean Chinese population and trans-ethnic genetic studies

Genetic factors underlying leukocyte telomere length (LTL) may provide insights into telomere homeostasis, with direct links to disease susceptibility. Genetic evaluation of 23,096 Singaporean Chinese samples identifies 10 genome-wide loci (P < 5 × 10-8). Several of these contain candidate genes (TINF2, PARP1, TERF1, ATM and POT1) with potential roles in telomere biology and DNA repair mechanisms. Meta-analyses with additional 37,505 European individuals reveals six more genome-wide loci, including associations at MPHOSPH6, NKX2-3 and TYMS. We demonstrate that longer LTL associates with protection against respiratory disease mortality [HR = 0.854(0.804-0.906), P = 1.88 × 10-7] in the Singaporean Chinese samples. We further show that the LTL reducing SNP rs7253490 associates with respiratory infections (P = 7.44 × 10-4) although this effect may not be strongly mediated through LTL. Our data expands on the genetic basis of LTL and may indicate on a potential role of LTL in immune competence.

Prevalence and Risk Factors for Frailty among Community-Dwelling Older People in China: A Systematic Review and Meta-Analysis

OBJECTIVE

To systematically assess the prevalence of frailty, including prefrailty, stratified prevalence according to frailty criteria, gender, age, and region, and the risk factors for frailty in China.

DESIGN

We conducted a systematic literature review and meta-analysis using articles available in 8 databases including PubMed, Cochrane Library, Web of Science, CINAHL Plus, China Knowledge Resource Integrated Database (CNKI), Wanfang Database, Chinese Biomedical Database (CBM), and Weipu Database (VIP).

SETTING

Cross-sectional and cohort data from Chinese community.

PARTICIPANTS

Community-dwelling adults aged 65 and older.

MEASUREMENTS

Two authors independently extracted data based upon predefined criteria. Where data were available we conducted a meta-analysis of frailty parameters using a random-effects model.

RESULTS

We screened 915 different articles, and 14 studies (81258 participants) were ultimately included in this analysis. The prevalence of frailty and prefrailty in individual studies varied from 5.9% to 17.4% and from 26.8% to 62.8%, respectively. The pooled prevalence of frailty and prefrailty were 10% (95% CI: 8% to 12%, I2 = 97.4%, P = 0.000) and 43% (95% CI: 37% to 50%, I2 = 98.0%, P = 0.000), respectively. The pooled frailty prevalence was 8% for the Fried frailty phenotype, 12% for the frail index, and 15% for the FRAIL scale. Age-stratified meta-analyses showed the pooled prevalence of frailty to be 6%, 15%, and 25% for those aged 65-74, 75-84, and ≥85 years old, respectively. The pooled prevalence of frailty was 8% for males and 11% for females. The pooled prevalence of frailty in Mainland China, Taiwan, and Hong Kong was 12%, 8%, and 14%, respectively. The pooled frailty prevalence was 10% in urban areas and 7% in rural areas. After controlling for confounding variables, increasing age (OR = 1.28, 95% CI: 1.2 to 1.36, I2 = 98.0%, P = 0.000), being female (OR = 1.29, 95% CI: 1.16 to 1.43, I2 =92.7%, P=0.000), activities of daily living (ADL) disability (OR = 1.72, 95% CI: 1.57 to 1.90, I2 = 99.7%, P = 0.000), and having three or more chronic diseases (OR = 1.97, 95% CI: 1.78 to 2.18, I2 = 97.5%, P = 0.000) were associated with frailty.

CONCLUSIONS

These findings of this review indicate an overall pooled prevalence of frailty among Chinese community-dwelling older people of 10%. Increasing age, being female, ADL disability, and having three or more chronic diseases were all risk factors for frailty. Further research will be needed to identify additional frailty risk factors in order to better treat and prevent frailty in the community.

Evaluation of androgen assay results using a curated Hershberger database

A set of 39 reference chemicals with reproducible androgen pathway effects in vivo, identified in the companion manuscript [1], were used to interrogate the performance of the ToxCast/Tox 21 androgen receptor (AR) model based on 11 high throughput assays. Cytotoxicity data and specificity confirmation assays were used to distinguish assay loss-of-function from true antagonistic signaling suppression. Overall agreement was 66% (19/29), with ten additional inconclusive chemicals. Most discrepancies were explained using in vitro to in vivo extrapolation to estimate equivalent administered doses. The AR model had 100% positive predictive value for the in vivo response, i.e. there were no false positives, and chemicals with conclusive AR model results (agonist or antagonist) were consistently positive in vivo. Considering the lack of reproducibility of the in vivo Hershberger assay, the in vitro AR model may better predict specific AR interaction and can rapidly and cost-effectively screen thousands of chemicals without using animals.

[Analysis of blood flow energy characteristics of pulsatile and non-pulsatile flow during extracorporeal circulation]

Objective: To analyze the magnitude of blood flow energy and characteristics of frequency domain between pulsatile flow and nonpulsatile flow during cardiopulmonary bypass and physiological flow. Methods: From January 2017 to December 2017, 60 cases of patients with mitral valve disease scheduled for mitral valve replacement or repair at Department of Cardiasurgery, Shanghai Chest Hospital, Shanghai Jiaotong University were randomly divided into 2 groups: pulsatile perfusion (PP) and non-pulsatile perfusion (NP). The magnitude of blood flow energy during pulsatile and non-pulsatile was calculated using energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE) while fast Fourier transformation (FFT) was used to perform power spectral density analysis to identify the frequency domain characteristics between artificial and physiological flow (prior to CPB). The data was analyzed by analysis of variance or t test. Results: At the different time-points after occlusion, the EEP and SHE in PP group were respectively 1.52 to 1.62 and 2.03 to 2.22 times higher than NP at the distal of artery filter. The power density analysis revealed that the blood flow energy of physiological pulsatile flow patterns was within 40 Hz and the ratio of low frequency energy was more than 90% before clamp. The spectral energy ratio of low frequency decreased in both group compared with physiological flow was more obvious in NP group at the radial artery. The ratio of estimated value of power density of PP and NP groups analysis showed the corresponding 0 to 5 Hz, 0 to 10 Hz, 0 to 40 Hz frequency range values measured at the radial artery and filter were 9.51, 4.68, 3.59 and 3.87, 2.69, 2.38 respectively after occulusion. In each frequency range, the energy of PP is higher than that of NP, and the lower the frequency, the greater the difference. The ratio of estimated value of power density of PP and NP groups for the three frequencies measured at the radial artery before and after occlusion were 2.86, 2.83, 2.75 and 14.70, 12.74, 9.85 respectively, and decreased significantly in NP group and low frequency energy. The ratio of estimated value of power density of PP and NP groups under the three different frequencies measured at the radial artery and filter were 26.35, 33.15, 37.36 and 37.41, 54.18, 56.64 respectively, in the conduction process from filter to radial artery, energy exhaustion is significant, especially in group NP. Conclusions: The PP provides significantly more energy than the NP whereby the PP is closer to the physiological pulsatile on the energy frequency structure and attenuation characteristics, with mainly low frequency energy of 0 to 5 Hz and weak energy attenuation. The energy loss of non-pulsatile flow is obvious, especially the low frequency energy.

Point-and-Shoot Strategy for Identification of Alcoholic Beverages

The lack of point-and-shoot detection methods of alcoholic beverages (ABs) available for ordinary people is a common cause of the overflow of various counterfeit ABs. Here, we, for the first time, provide a point-and-shoot identification for ABs via a smartphone. Using density functional theory, we find the binding ability of an ethylenediamine-functionalized polydiacetylene (P4) can reach a desirable trade-off among organic molecules in ABs. We therefore construct a versatile array consisting of P4 with different concentrations, which is able to generate unique color response patterns toward different ABs. The color response patterns are further analyzed by a custom-designed image processing algorithm based on machine learning. Finally, the identification of ABs can be achieved by capturing and analyzing the color pattern using an imaging recognition programmer on a smartphone, and the entire process is as fast as quick response (QR) code scanning. Our point-and-shoot strategy makes the identification of ABs accessible to every mobile phone user.