HCMV-miR-US33-5p promotes apoptosis of aortic vascular smooth muscle cells by targeting EPAS1/SLC3A2 pathway

Background

In patients with acute aortic dissection (AAD), increased vascular smooth muscle cell (VSMC) apoptosis has been found. Human cytomegalovirus (HCMV)-miR-US33-5p was significantly increased in the plasma of patients with AAD. However, the roles of miR-US33-5p in human aortic VSMC (HA-VSMC) apoptosis remain to be elucidated.

Methods

In the current study, cell apoptosis was analyzed by flow cytometry, cell proliferation by CCK-8 assay, and differentially expressed genes by RNA sequencing. Luciferase reporter assay was used for binding analysis between miR-US33-5p and endothelial PAS domain protein 1 (EPAS1), and EPAS1 and amino acid transporter heavy chain, member 2 (SLC3A2). The enrichment degree of SLC3A2 promoter DNA was analyzed by chromatin immunoprecipitation assay. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and immunoblotting were performed for measuring messenger RNA (mRNA) and protein levels, respectively.

Results

It was found that HCMV infection inhibited proliferation but promoted HA-VSMC apoptosis by upregulating HCMV-miR-US33-5p. Transfection of HCMV-miR-US33-5p mimics the significant effect on several signaling pathways including integrin signaling as shown in the RNA sequencing data. Western blotting analysis confirmed that HCMV-miR-US33-5p mimics suppression of the activity of key factors of the integrin signal pathway including FAK, AKT, CAS, and Rac. Mechanistic study showed that HCMV-miR-US33-5p bound to the 3′-untranslated region of EPAS1 to suppress its expression, leading to suppression of SLC3A2 expression, which ultimately promoted cell apoptosis and inhibited cell proliferation. This was confirmed by the findings that silencing EPAS1 significantly reduced the SLC3A2 expression and inhibited proliferation and key factors of integrin signal pathway.

Conclusions

HCMV-miR-US33-5p suppressed proliferation, key factors of integrin signal pathway, and EPAS1/SLC3A2 expression, but promoted HA-VSMC apoptosis. These findings highlighted the importance of HCMV-miR-US33-5p/EPAS1/SCL3A2 signaling and may provide new insights into therapeutic strategies for AAD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-022-00340-w.

Women-specific risk factors and risk of incident atrial fibrillation in UK Biobank

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and carries a large morbidity and mortality risk. Recent evidence suggests differences in epidemiology and pathophysiology of AF between women and men and underscores a poorer prognosis of AF among women. This calls for further investigation regarding the impact of women-specific risk factors on AF development.

Purpose

To investigate the association between women-specific risk factors and new-onset AF.

Methods

235,191 women (mean [standard deviation] age: 55.7 [8.1] years) free of AF and without a history of hysterectomy and/or bilateral oophorectomy from the UK Biobank were included. Various women-specific risk factors were assessed from 2006 to 2010. Follow-up of new-onset AF occurred through October 2020. Cox proportional hazards analyses were performed to investigate prospective associations between each risk factor and incident AF. Additionally, natural splines were used to identify any potential nonlinear associations.

Results

After a median follow-up of 11.6 (interquartile range: 10.9–12.3) years, 4,629 (2%) women experienced new-onset AF. In fully adjusted models, having experienced irregular menstrual cycle was significantly associated with increased new-onset AF risk [hazard ratio (HR); 95% confidence interval (CI): 1.34; 1.01-1.79]. In addition, nonlinear associations were found between menopausal age, menarcheal age, number of live births, and number of total reproductive years with incident AF. Compared to the reference, early menopause (menopause <45 years of age) or delayed menopause (>60 years) significantly increased risks of incident AF (HR; 95CI: 1.24; 1.10-1.39 and 1.34; 1.01-1.78, respectively). Compared to the reference, both early menarche (menarche ≤11 years) and late menarche (menarche ≥13 years) were associated with AF incidence (HR; 95CI: 1.10; 1.00-1.21 and 1.08; 1.00-1.17, respectively). Compared to women with one or two children, having no children (HR; 95CI: 1.13; 1.04-1.24), or more than six children (HR; 95%CI: 1.67; 1.03-2.70) were associated with higher AF risks. Having reproductive years ≤20 years was significantly associated with incident AF (HR; 95CI: 1.74; 1.07-2.86).

Conclusions

Having experienced early or delayed menopause, early or late menarche, or irregular menstrual cycles conferred higher risks of incident AF among women in the UK Biobank. Interestingly, both nulliparity and multiparity, compared to having one or two children, were associated with an increased AF risk. Our results highlight the importance of knowledge regarding the reproductive history of women in devising screening strategies for AF prevention.

Fate of thiamethoxam from treated seeds in mesocosms and response of aquatic invertebrate communities

Thiamethoxam is a neonicotinoid insecticide widely applied in the Canadian Prairies. It has been detected in surface waters of agro-ecosystems, including wetlands, but the potential effects on non-target invertebrate communities in these wetlands have not been well characterized. In an effort to understand better the fate of thiamethoxam in wetlands and the response of invertebrates (zooplankton and emergent insects), model systems were used to mimic wetland flooding into planted fields. Outdoor mesocosms were treated with a single application of thiamethoxam-treated canola seeds at three treatment levels based on a recommended seeding rate (i.e., 6 kg/ha; 1×, 10×, and 100× seeding rate) and monitored over ten weeks. The mean half-life of thiamethoxam in the water column was 6.2 d. There was no ecologically meaningful impact on zooplankton abundances or community structure among treatments. Statistically significant differences were observed in aquatic insect abundance between control mesocosms and the two greatest thiamethoxam treatments (10× and 100× seeding rate). The observed results indicate exposure to thiamethoxam at environmentally relevant concentrations likely does not represent a significant ecological risk to abundance and community structure of wetland zooplankton and emergent insects.

Multidimensional, High Precision Measurements of Beam Single Spin Asymmetries in Semi-inclusive π^{+} Electroproduction off Protons in the Valence Region

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π^{+} SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q^{2} ranging from 1-7  GeV^{2}. In particular, the structure function ratio F_{LU}^{sinϕ}/F_{UU} has been determined, where F_{LU}^{sinϕ} is a twist-3 quantity that can reveal novel aspects of emergent hadron mass and quark-gluon correlations within the nucleon. The data's impact on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.

Predictive Value of Geriatric Nutritional Risk Index in Older Adult Cancer Patients

BACKGROUND AND AIMS

To compare the association of geriatric nutritional risk index (GNRI) and controlling nutritional status (CONUT) scores with malnutrition, and to study their association with clinical outcomes in older adult cancer patients.

METHODS

This retrospective analysis was conducted on 854 older adult cancer patients collected from 34 hospitals in 18 cities in China between June and September 2014. Anthropometric and hematological examination results at admission were collected, and subjective global assessment was used. Clinical outcomes, such as complications, length of hospital stays, and hospital costs, were recorded. Receiver operating characteristic curves were used to evaluate the accuracy of the two nutritional assessment tools for malnutrition. The association between GNRI and CONUT score and clinical outcomes was analyzed using the chi-square test, t-test, or rank sum test.

RESULTS

Among 854 patients with cancer, the prevalence of malnutrition was 42.7%. Compared with subjective global assessment, the GNRI had a significantly higher accuracy than the CONUT score in predicting malnutrition (area under the curve 0.704, 95% confidence interval, 0.658 - 0.750, P < 0.001). The GNRI was significantly associated with the occurrence of complications (χ2 = 4.985, P = 0.026), and low GNRI (≤98) was associated with a longer length of hospital stay (t = -2.179, P = 0.030).

CONCLUSIONS

The GNRI may be used to assess malnutrition in older adult cancer patients and can predict poor clinical outcomes in these patients.

The global prevalence of sexual violence against pregnant women: a systematic review and meta-analysis

When committed against pregnant women, sexual violence may have adverse health consequences for both the mother and the unborn child. To date, no studies have systematically summarized the global prevalence of sexual violence against pregnant women. We conducted a comprehensive search of PubMed, Embase and Web of Science from inception dates to January 2021 for studies reporting the prevalence of sexual violence against pregnant women. Prevalence was estimated using a random-effects meta-analysis. Heterogeneity was evaluated using the I² statistic. Differences by study level characteristics were estimated through subgroup analysis and meta-regression. A total of 10 cross-sectional studies (a total of 8,439 participants) were included. The pooled proportion of sexual violence was 0.31 (95% CI: 0.22-0.40). Subgroup analyses showed higher prevalence of sexual violence against pregnant women in the 2010-2019 period (0.35, 95% CI0.15-7.53) and developing countries (0.32, 95% CI0.19-0.45). Almost one in three (31%) pregnant women around the world has been a victim of sexual violence in their lifetime. Sexual violence against pregnant women continues to be a major public health challenge. The global prevalence of sexual violence against pregnant women warrants the collective attention of the entire society.

Standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery for sacrocolpopexy

We describe the standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery (vNOTES) for sacrocolpopexy in women with uterine prolapse. In this video, we demonstrate the key techniques: identifying the right hypogastric nerve (rHN) before opening the pelvic peritoneum; removing the fat and loose connective tissue along the rHN to expose the presacral fascia; incising the presacral fascia to reach the presacral space to expose the middle sacral vasculature and the anterior longitudinal ligament (ALL) of the first sacral vertebra (S1) below the promontory; attaching the mesh to the ALL to avoid vessel injury; and completing the peritonealisation.

Study on a new manner of the magnetization switching actuated by a unidirectional pulse current

A new writing scheme with a unidirectional pulse current is proposed for spin transfer torque (STT) based magnetic random-access memory (MRAM). To investigate the feasibility of the writing scheme, bilayered nano-pillars composed of a soft layer with small in-plane shape anisotropy and a hard layer with either large perpendicular anisotropy (PMA) or in-plane anisotropy (IMA) are designed and their switching behaviors are studied. It is found that in either type of bilayered nano-pillars, with the aid of the attached hard layer, the magnetization of the soft layer can be switched back and forth under a unidirectional pulse current. In an IMA/IMA nano-pillar, the magnetization of the free layer (FL) can achieve excellent alignment, which is in contrast to the IMA/PMA nano-pillar. By optimizing the dimensions and magnetic parameters of the IMA/IMA nano-pillar, a decently low switching current density (4.3 × 10¹¹A m^-2) and ultrashort switching time (<1 ns) can be reached. Based on these results, the unidirectional writing scheme is practical if an IMA/IMA bilayer is used to replace the FL in a magnetic tunnel junction. Considering that a unidirectional writing scheme can enable the application of materials with high spin polarization such as half metals, and avoid the injection of writing current into junction using a special design, it may be very promising for STT-MRAM.

Imaging-based body fat depots and new-onset atrial fibrillation in general population

Background

Obesity is a well-established risk factor for incident atrial fibrillation (AF). Whether different body fat depots differentially associate with AF development remains largely unknown.

Purpose

We aimed to investigate the associations between various body fat depots and the risk of new-onset AF among middle-aged and elderly individuals from general population.

Methods

In the prospective population-based cohort study, body composition was assessed using dual-energy X-ray absorptiometry (DXA) and total body mass, lean mass, fat mass, android and gynoid fat were analyzed (N=3468). Liver fat and epicardial fat were assessed using computed tomography (CT) (N=2145). A body fat score was defined by adding tertiles of each fat depot. All participants were followed for the occurrence of AF until 1st Jan. 2014. Principle component analysis was conducted to identify body fat distribution patterns. Time-to-event analyses were performed using Cox proportional hazards regression analysis. Hazard ratios (HR) and 95% confidence-intervals (95% CI), adjusted for cardiovascular risk factors, were calculated.

Results

Mean (standard deviation) of age for participants in DXA study and CT study was 74.42 (6.85) and 68.66 (6.41) years, respectively. AF incidence rate was 13.1 per 1000 person-years during a median follow-up time of 9.62 years. In the adjusted model, fat mass (HR; 95% CI: 1.33; 1.05–1.68), lean mass (1.40; 1.15–1.72), gynoid fat mass (1.36; 1.12–1.65), and total body mass (1.51; 1.21–1.89) were significantly associated with new-onset AF. Of note, android-to-gynoid fat ratio was inversely associated with incident AF (HR; 95% CI: 0.81; 0.70–0.94). Larger body fat score was associated with increased risk of incident AF (P for trend &lt;0.01). Two fat distribution patterns were identified. Adherence to the fat- and gynoid fat- pattern (P for trend = 0.035), but not muscle- and visceral fat- pattern (P for trend = 0.35), was significantly associated with larger risk of new-onset AF.

Conclusions

Various body fat depots were associated with new-onset AF. Larger values of total body mass carried the highest risk for incident AF. The inverse association between android to gynoid fat ratio with AF presents a novel finding. A significant dose-response relationship between body fat accumulation and risk of new-onset AF was observed, implying a collective impact of fat depots on AF development. Findings also suggest that various fat depots, characterized by different fat distribution patterns, may exert differential combined effect on the risk of incident AF.

Funding Acknowledgement

Type of funding sources: None. Fat depots and atrial fibrillation

Constipation is associated with worse prognosis of thrombolytic AIS: a single-center prospective study

Background and purpose

Previous clinical studies have found that constipation was associated with the prognosis of ischemic stroke patients. This information may provide new ideas for thrombolytic AIS (acute cerebral arterial thrombosis) patients' short-term prognostic assessment. Our study was designed to investigate the risk factors of constipation and its association with the prognosis in thrombolytic AIS patients.

Methods

The prospective cohort study included 97 AIS patients treated with intravenous thrombolysis. Three days without defecation in thrombolytic patients was recorded as constipation in clinic. The risk factors for constipation included demographics, clinical characteristics, laboratory parameters and partial treatments. Scores of NIHSS and mRS and length of stay (LOS) in ICU and hospital were used to evaluate the effect of constipation on patients' neurological function and short-term prognosis.

Results

The incidence of constipation was 49.48% in the first three days after intravenous thrombolysis. The use of stomach tube and antibiotics made patients more prone to constipation (odds ratio OR: 5.01, 95% CI: 2.04–12.32, P=0.000; odds ratio: 6.06, 95% CI: 2.35–15.61, P=0.000). The occurrence of constipation resulted in significantly longer ICU and hospital LOS (2.29±1.63 versus 4.75±4.22, P=0.000; 11.08±10.01 versus 15.73±12.36, P=0.044). Moreover, constipation worsened the thrombolytic AIS patients' short-term neurological recovery (mRS at 3 months: 1.53±1.72 versus 2.41±1.92, P=0.02). Oral probiotics for constipation during hospitalization not only prolonged patients' stay in the ICU (2.91±2.28 versus 6.44±4.88, P=0.003), but also resulted in poorer short-term neurological functional outcomes (mRS at 3 months: 1.57±1.53 versus 3.26±1.91, P=0.002).

Conclusions

The occurrence of constipation in the first three days was associated with the longer ICU and hospital stay and a worse short-term prognosis, suggesting that constipation may be a predictor of thrombolytic AIS patients' prognosis. Further studies of constipation and its appropriate therapy strategy are needed to solve the plight of thrombolytic AIS with constipation.

Funding Acknowledgement

Type of funding sources: None.

Distribution and risk profile of atrial fibrillation patterns among women and men from the general population

Background

In a clinical setting, atrial fibrillation (AF) subgroups are defined, including paroxysmal, persistent, and permanent AF. These subgroups differ in terms of clinical characteristics, management strategy, and long-term outcomes. Application of clinical classifications in population-based settings is challenging as they are based on the duration of symptoms, recurrence, and treatment.

Purpose

We aim to develop an objective and standardized classification for AF patterns in the general population and examine the associated cardiovascular risk profiles and outcomes for the identified AF patterns.

Methods

Participants with only one reported AF episode were categorized as single-documented AF, if at least two separate AF episodes were reported as multiple-documented AF and as longstanding persistent AF if at least two consecutive ECG's at the research center showed AF, not followed by an ECG showing sinus rhythm. We fitted mixed effect models with age as time scale to characterize sex-specific cardiovascular risk factor trajectories preceding each AF pattern. We further used Cox proportional hazard modelling to describe the risk of coronary heart disease (CHD), heart failure (HF), stroke, and all-cause mortality following AF.

Results

We included 14,620 men and women aged ≥45 years. 1137 participants were categorized as single-documented AF, 208 as multiple-documented AF, and 57 as longstanding persistent AF. We identified significant differences in the preceding trajectories of weight, body mass index, systolic blood pressure, diastolic blood pressure, waist circumference, hip circumference, and waist-hip ratio with various AF patterns. In general, both men and women with persistent-elevated levels of these risk factors were prone to longstanding persistent AF.

AF was associated with a large risk for subsequent CHD, HF, stroke, and mortality in the general population. Among the different AF patterns, single-documented AF conferred the largest risk of CHD [hazard ratio, 95% confidence interval: 1.92 (1.19–3.03)] and mortality [1.70 (1.41–2.07)] as compared to multiple-documented AF, and as compared to longstanding persistent AF [1.45 (0.72–2.90) and 3.66 (2.25–5.95), respectively].

Conclusion

We developed a classification for AF patterns within a general population. We identified differences in risk factor trajectories preceding each AF pattern, which implies differences in pathophysiological mechanisms underlying AF. Participants with single-documented AF showed worse prognosis than those with multiple AF episodes. This might be due to the subgroup definition, since participants should live for a longer period of time to be categorized in the multiple-documented AF and longstanding persistent AF groups. This can also imply that participants suffering from multiple AF episodes are more frequently monitored, and treated for other risk factors. However, this could also suggest that singular AF episodes are not as innocent as commonly thought.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): - Erasmus MC Mrace grant. - Netherlands Organization for the Health Research and Development (ZonMw) Figure 1Figure 2. Progosis of various AF patterns

Prognostic nutrition index predicts outcomes in critically ill stroke patients: a database-based cohort study

Background

Although there are many indicators to assess nutritional status, a more comprehensive and objective indicator is still needed in clinical practice. In this study, we evaluated the relationship between the prognostic nutritional index (PNI) and clinical outcomes in patients with critically ill stroke.

Methods

Subjects who were diagnosed as stroke in the Beth Israel Deaconess Medical Center between 2001 and 2012 were identified from the Medical Information Mart for Intensive Care (MIMIC) III database. PNI was calculated as 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (per mm3). The multivariate logistic regression and the Cox regression analysis were performed to assess the impact of PNI on 3-month and 4-year mortality in stroke patients.

Results

A total of 624 subjects were included in this study. Compared with the high-PNI group, those in the Low PNI group had lower body mass index (BMI), hemoglobin, neutrophil count, lymphocyte count and albumin. On the contrary, Age, Blood urea nitrogen (BUN), Creatinine (Cre), simplified acute physiologic scoreII (SAPSII) score and sequential organ failure assessment (SOFA) score of the low PNI group were higher than the high PNI group. After adjusting for other confounders, PNI was independently associated with 3-month mortality (adjusted odds ratio = 1.910; 95% confidence interval, 1.244–2.933; P=0.003). By the Kaplan-Meier analysis, patients in the low PNI group presented significantly shorter survival time and higher death rate. The Cox regression model indicated low PNI as an independent risk factor of 4-year all-cause mortality of stroke patients (hazard ratio = 1.824; 95% CI, 1.340–2.483; P&lt;0.001).

Conclusions

Low PNI is independently associated with short-term and long-term prognosis in patients with critically ill stroke.

Funding Acknowledgement

Type of funding sources: None.

Trajectories of metabolic risk factors and risk of new-onset atrial fibrillation among men and women

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia with major public health impact. Obesity and hypertension are among the most important risk factors to AF development. The link between AF and its pathogenetic factors are complex and comprehensive assessment of the impact of various long-term trajectories of anthropometric measures and blood pressure on incident AF among men and women is sparse.

Purpose

To investigate sex-specific trajectories of various anthropometric measures and blood pressure at population level, and further assess the impact of these trajectories on incident AF.

Methods

We included 5263 participants (mean age 72.1 years) with available repeated assessments measured 2 to 4 times for weight, body mass index (BMI), hip circumference (HC), waist circumference (WC), waist-to-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP) and mean arterial pressure (MAP). Latent class linear mixed model with age as the time scale were fitted to identify the potential various classes in each risk factor. Cox proportional hazards regression models were used to assess the association between risk factors' trajectories and risk of new-onset AF, with the most favorable trajectory as a reference. Models were adjusted for traditional cardiovascular risk factors.

Results

2159 (41.0%) of all participants were men. Median follow-up time was 9.76 years during which the incidence rate of AF was 16.2 per 1000 person-years for men, and 11.3 per 1000 person-years for women. In full-adjusted model, various trajectories of BMI, HC, and MAP were significantly associated with incident AF among men, and trajectories of weight, BMI, WC, HC, SBP, PP and MAP were significantly associated with incident AF among women. For BMI, persistent-increasing BMI trajectory carried the highest risk for AF with hazard ratio (HR) and 95% confidence interval (95% CI) of 1.39 (1.05–1.85) in men and 1.60 (1.19–2.15) in women. Also, persistently increasing trajectories of weight [1.69 (1.20–2.37)], WC [1.39 (1.04–1.86)] and HC [1.56 (1.05–2.34)] among women conferred the largest risks. For SBP, the persistently hypertensive trajectory carried the largest risk for AF among women [2.06 (1.25–3.39)], while intensively increasing SBP trajectory conferred the largest risk among men [1.34 (0.89–2.02)], albeit non-significant. Similar associations were observed for MAP among men and women; associated risks were 1.77 (1.25–2.51) for the persistent-hypertensive trajectory in women and 1.64 (1.16–2.33) for the intensive-increasing trajectory in men.

Conclusions

Various trajectories of metabolic risk factors were associated with new-onset AF among men and women. Sex-specific associations between SBP and MAP with AF could imply the differential long-term impact of vascular function on AF development among men and women. This highlights the importance of sex-specific preventive strategies for AF in general population.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Gender and Prevention grant, ZonMwCSC scholarship for PhD research

Genome shuffling of Lactobacillus plantarum 163 enhanced antibacterial activity and usefulness in preserving orange juice

Lactic acid bacteria have been used to inhibit the growth of spoilage bacteria in food and animal feeds. For instance, Lactobacillus plantarum 163 can inhibit efficiently the growth of both gram-positive and gram-negative bacteria. In our study, the antibacterial activity of L. plantarum 163 was further improved significantly by genome shuffling. The optimal conditions for protoplast formation and regeneration were 20 mg ml^-1 lysozyme and 5 mg ml^-1 mutanolysin for 30 min at 37°C using 0·5 mol l^-1 sucrose as stabilizer. The protoplasts were inactivated under ultraviolet light for 120 s or heated at 58°C for 20 min. After two rounds of genome shuffling, the inhibitory activity of strain F2-14 was improved by 2·45- and 1·99-fold, respectively, as compared to their parent strains. The prepared antibacterial peptides supernatant (APS) was added to the orange juice to inhibit spores of Alicyclobacillus acidoterrestris (SAA) at 45 and 28°C. Results showed that the growth of A. acidoterrestris was significantly inhibited, and the decrease in total soluble solids, OD value and pH value was also delayed. After treatment with APS, the thermal sensitivity of spores was increased and its D value was reduced to 13·78, 3·87 and 1·47 min at 80, 90 and 95°C respectively.

What is an appropriate caesarean delivery rate for China: a multicentre survey

Objective

To assess the current status of caesarean delivery (CD) in China, propose reference CD rates for China overall, and by regions, investigate the main indications for CDs and identify possible areas for safe reduction.

Design

A multicentre cross‐sectional study.

Setting

A total of 94 hospitals across 23 provinces in China.

Population

A total of 73 977 randomly selected deliveries.

Methods

We used a modified Robson classification to characterise CDs in subgroups and by regions, and the World Health Organization (WHO) C‐Model to calculate reference CD rates.

Main outcome measures

CD rates in China.

Results

In 2015–2016, the overall CD rate in China was 38.9% (95% CI 38.6–39.3%). Considering the obstetric characteristics of the population, the multivariable model‐based reference CD rate was estimated at 28.5% (95% CI 28.3–28.8%). Accordingly, an absolute reduction of 10.4% (or 26.7% relative reduction) may be considered. The CD rate varied substantially by region. Previous CD was the most common indication in all regions, accounting for 38.2% of all CDs, followed by maternal request (9.8%), labour dystocia (8.3%), fetal distress (7.7%) and malpresentation (7.6%). Overall, 12.7% of women had prelabour CDs, contributing to 32.8% of the total CDs.

Conclusions

Nearly 39% of births were delivered by caesarean in China but a reduction of this rate by a quarter may be considered attainable. Repeat CD contributed more than one‐third of the total CDs. Given the large variation in maternal characteristics, region‐specific or even hospital‐specific reference CD rates are needed for precision management of CD.

Tweetable abstract

The caesarean rate in 2015–2016 in China was 38.9%, whereas the reference rate was 28.5%.

The caesarean rate in 2015–2016 in China was 38.9%, whereas the reference rate was 28.5%.

Linked article This article is commented on by M Varner, p. 148 in this issue. To view this mini commentary visit https://doi.org/10.1111/1471-0528.16953.

Whole genome survey and genetic markers development of crocodile flathead Cociella crocodilus

Flatheads in family Platycephalidae are ecologically and commercially important marine fish species in the Indo-West Pacific. Due to similar morphological characters, the taxonomy and phylogenetics of flatheads are in confusion. Studies on phylogenetics and molecular marker development are required to discriminate congeners of flatheads. In the present study, we performed whole genome survey sequencing of crocodile flathead Cociella crocodilus to provide genomic information and genetic markers of this species. In total, 54.03 Gb of clean genomic data were generated. The genome size was estimated to be 732.99 Mb with the heterozygosity ratio of 0.73% and the repeat sequence ratio of 33.48%. The preliminary assembled genome sequences were 794.07 Mb with contig N50 of 1504 bp. We detected 2 624 875 genome-wide SNPs with transition/transversion ratio of 1.422. A total of 313 842 microsatellite motifs were identified, most of which were dinucleotide motifs with a frequency of 74.89%. In addition, we assembled the complete mitogenome of C. crocodilus and subsequent phylogenetic analysis were performed. Phylogenetic analyses revealed numbers of polyphyletic groups in family Platycephalidae. The reported genomic data and genetic markers in our study should be useful in further phylogeny and phylogenomics studies of flathead species.

Two atypical gram-negative bacteria-binding proteins are involved in the antibacterial response in the pea aphid (Acyrthosiphon pisum)

The activation of immune pathways is triggered by the recognition of pathogens by pattern recognition receptors (PRRs). Gram-negative bacteria-binding proteins (GNBPs)/β-1,3-glucan recognition proteins (βGRPs) are a conserved family of PRRs in insects. Two GNBPs are predicted in the genome database of pea aphids; however, little is known about their functions in the aphid immune system. Here, we show that pea aphid GNBPs possess domain architectures and sequence features distinct from those of typical GNBPs/βGRPs and that their expression is induced by bacterial infection. Knockdown of their expression by dsRNA resulted in lower phenoloxidase activity, higher bacterial loads and higher mortality in aphids after infection. Our data suggest that these two atypical GNBPs are involved in the antibacterial response in the pea aphid, likely acting as PRRs in the prophenoloxidase pathway.

CodY, ComA, DegU and Spo0A controlling lipopeptides biosynthesis in Bacillus amyloliquefaciens fmbJ

AIM

In the study, we investigated the regulatory effects of these genes (codY, comA, degU and spo0A) on the biosynthesis of three lipopeptides (bacillomycin D, fengycin and surfactin) in Bacillus amyloliquefaciens.

METHODS AND RESULTS

The codY, comA, degU and spo0A genes in B. amyloliquefaciens fmbJ were knocked out. The results showed that the productions of bacillomycin D were significantly reduced compared with that of fmbJ. Their deletion induced great changes in the levels of transcripts specifying metabolic pathways, quorum sensing system and substance transport system in fmbJ. Moreover, overexpression of these genes improved the productions of bacillomycin D. In particular, the overexpression of spo0A enhanced bacillomycin D yield up to 648·9 ± 60·9 mg l^-1 from 277·3 ± 30·5 mg l^-1 . In addition, the yields of surfactin in fmbJΔcodY and fmbJΔdegU were significantly improved, and the regulatory factor CodY had no significant effect on the synthesis of fengycin.

CONCLUSIONS

These genes positively regulated the expression of bacillomycin D and fengycin synthase genes in strain fmbJ. However, codY and degU negatively regulated surfactin biosynthesis. Moreover, it was found that CodY had a concentration dependence on bacillomycin D synthesis. Spo0A might play a direct regulatory role in the synthesis and secretion of bacillomycin D.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study indicated that genetic engineering of regulatory genes was an effective strategy to improve the yields of antimicrobial lipopeptides and provided promising strains for industrial production of lipopeptides.

Validation of the Construct of Intrinsic Capacity in a Longitudinal Chinese Cohort

OBJECTIVES

We examined the structure and predictive ability of intrinsic capacity in a cohort of Chinese older adults.

METHODS

We used data from the MrOS and MsOS (Hong Kong) study, which was designed to examine the determinants of osteoporotic fractures and health in older Chinese adults. We analysed baseline and the 7-year follow-up data using exploratory factor analysis, confirmatory factor analysis (CFA), and mediation analysis.

RESULTS

The study consisted of 3736 participants at baseline (mean 72.2 years), with 1475 in the 7-year follow-up. Bi-factor CFA revealed five sub-factors labelled as 'cognitive', 'locomotor', 'vitality', 'sensory', and 'psychological' and one general factor labelled as 'intrinsic capacity'. The model fits the data well, with Root Mean Square Error of Approximation (RMSEA)=0.055 (90% CI=0.053-0.058) for the 5-factor model and RMSEA=0.031 (90% CI=0.028-0.035) for the bi-factor model. Significantly lower intrinsic capacity scores were found in older age groups, women, as well as those who had lower levels of education, lower subjective social status, reported more chronic diseases, or a higher number of IADL limitations (All p<0.0001). Intrinsic capacity had a direct effect in predicting incident IADL limitations at the 7-year follow-up (β=-0.21, p<0.001). The effect was larger than the direct effect of the number of chronic diseases on incident IADL limitations (β=0.05, not significant).

CONCLUSIONS

This study supports the construct and predictive validity of the proposed capacity domains of intrinsic capacity. The findings could inform the development of an intrinsic capacity score that would facilitate implementation of the concept of intrinsic capacity in clinical practice.

Association of Frailty Status with Risk of Fall among Middle-Aged and Older Adults in China: A Nationally Representative Cohort Study

OBJECTIVES

To investigate the association between frailty status and risk of fall among middle-aged and older Chinese people.

DESIGN

A nationally representative prospective cohort study.

SETTING AND PARTICIPANTS

The study included 13,877 community-dwelling participants aged 45 years and above from the China Health and Retirement Longitudinal Study.

METHODS

Frailty status was identified by the frailty index of health deficit accumulation. 34 variables at baseline were selected to calculate the frailty index. We excluded participants with incomplete information in construction of the frailty index at baseline. Falls were measured based on the respondents' self-report. We used a logistic regression model to estimate the associations between the frailty status and risk of fall, and subgroup analyses and sensitivity analyses were further conducted.

RESULTS

Of 13,877 participants, 2310 (16.6%) had falls during the observation period. 9027 (65.0%) participants were classified as robust, 4019 (29.0%) participants were classified as pre-frail, and 831 (6.0%) participants were classified as frail. Our results indicated per 0.01 increment in the frailty index was significantly associated with an increased risk of fall among middle-aged and older participants (OR: 1.52, 95%CI: 1.45-1.60). Such association was stronger when frailty was presented as a categorical variable, with an OR of 1.75 (95%CI: 1.59-1.93) for pre-frail and 3.04 (95%CI: 2.60-3.56) for frail. The area under the curve of the logistic model was 0.612 (95%CI: 0.600-0.625). Each 0.01 increment of the frailty index was association with a higher risk of fall among middle-aged (45-59years) participants (OR: 1.44, 95%CI: 1.29-1.60) than among older (≥60 years) participants (OR: 1.28, 95%CI: 1.16-1.41) at baseline (p=0.015 for interaction).

CONCLUSION

Frailty was significantly associated with an increased risk of fall among community-dwelling middle-aged and older people in China. It is necessary to screen and recognize frailty status to prevent falls among middle-aged and older adults.

Chicory fibre improves reproductive performance of pregnant rats involving in altering intestinal microbiota composition

AIM

Chicory fibre (CF) is rich in fructan, which always functions as a quality dietary fibre source during mammalian pregnancy; however, its effect on reproductive performance remains unclear.

METHODS AND RESULTS

40 pregnant SD rats were randomly allotted to receive one of four diets: basal diet (control group), basal diet + 5% CF, basal diet + 10% CF, and basal diet + 15% CF, respectively. We found that CF significantly increased the number born alive and total litter birth weight (P < 0·05), increased the expression of intestinal tight junction proteins, mucins and antimicrobial peptides, accompanied by the increase of villi height and the decrease of crypts depth of pregnant SD rats (P < 0·05). We also observed that CF markedly increased the acetic acid, propanoic acid, butyric acid and total SCFAs concentrations in caecum contents and promoted the expression of SCFAs-related receptors (P < 0·05). Notably, rats fed CF increased the relative abundance of Bacteroidetes (P < 0·001), decreased the relative abundance of Firmicutes and Proteobacteria, while markedly lowered the Firmicutes/ Bacteroidetes ratio (F/B ratio) (P < 0·05). Intriguingly, the number born alive and total litter birth weight were positively correlated with some probiotics and negatively correlated with other harmful bacteria by Pearson correlation analysis.

CONCLUSION

Collectively, CF can enhance intestinal barrier function and maintain intestinal health, and may improve reproductive performance by altering intestinal microbiota composition.

SIGNIFICANCE AND IMPACT OF THE STUDY

Adding suitable dietary fibre to the diet can improve the reproductive performance of sows. Indeed, there exist various problems in the application of traditional dietary fibres, including high insoluble fibre content and anti-nutritional factor level, and mycotoxin contamination. This study demonstrates that dietary CF supplementation improves reproductive performance and intestinal health. Thus, CF can be applied in pregnancy animals as a new dietary fibre additive in animal husbandry.