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To investigate the effects of dietary fiber on follicular atresia in pigs fed a high-fat diet, we fed 32 prepubescent gilts a basal diet (CON) or a CON diet supplemented with 300 g/d dietary fiber (fiber), 240 g/d soy oil (SO), or both (fiber + SO). At the 19th day of the 4th estrus cycle, gilts fed the SO diet showed 112% more atretic follicles and greater expression of the apoptotic markers, Bax and Caspase-3, and these effects were reversed by the fiber diet. The abundance of short-chain fatty acid-producing microbes was decreased by the SO diet, but this effect was reversed by fiber treatment. Concentrations of serotonin and melatonin in the serum and follicular fluid were increased by the fiber diet. Overall, dietary fiber protected against high-fat feeding induced follicular atresia at least partly via gut microbiota-related serotonin–melatonin synthesis. These results provide insight into preventing negative effects on fertility in humans consuming a high-energy diet.
During pulsar navigation, the high-frequency noise carried by the pulsar profile signal reduces the accuracy of the pulse TOA (Time of Arrival) estimation. At present, the main method to remove signal noise by using wavelet transform is to redesign the function of the threshold and level of wavelet transform. However, the signal-to-noise ratio and other indicators of the filtered signal need to be further optimised, so a more appropriate wavelet basis needs to be designed. This paper proposes a wavelet basis design method based on frequency domain analysis to improve the denoising effect of pulsar signals. This method first analyses the pulsar contour signal in the frequency domain and then designs a Crab pulsar wavelet basis (CPn, where n represents the wavelet basis length) based on its frequency domain characteristics. In order to improve the real-time performance of the algorithm, a wavelet lifting scheme is implemented. Through simulation, this method analyses the pulsar contour signal data at home and abroad. Results show the signal-to-noise ratio can be increased by 4 dB, the mean square error is reduced by 61% and the peak error is reduced by 45%. Therefore, this method has better filtering effect.
Bile acids (BA) have emerged as signalling molecules regulating intestinal physiology. The importance of intestinal microbiota in production of secondary BA, for example, lithocholic acid (LCA) which impairs enterocyte proliferation and permeability, triggered us to determine the effects of oral probiotics on intestinal BA metabolism. Piglets were weaned at 28 d of age and allocated into control (CON, n 14) or probiotic (PRO, n 14) group fed 50 mg of Lactobacillus plantarum daily, and gut microbiota and BA profile were determined. To test the potential interaction of LCA with bacteria endotoxins in inducing damage of enterocytes, IPEC-J2 cells were treated with LCA, lipopolysaccharide (LPS) and LCA + LPS and expressions of genes related to inflammation, antioxidant capacity and nutrient transport were determined. Compared with the CON group, the PRO group showed lower total LCA level in the ileum and higher relative abundance of the Lactobacillus genus in faeces. In contrast, the relative abundances of Bacteroides, Clostridium_sensu_stricto_1, Parabacteroides and Ruminococcus_1, important bacteria genera in BA biotransformation, were all lower in the PRO than in the CON group. Moreover, PRO piglets had lower postprandial glucagon-like peptide-1 level, while higher glucose level than CON piglets. Co-administration of LPS and LCA led to down-regulated expression of glucose and peptide transporter genes in IPEC-J2 cells. Altogether, oral L. plantarum altered BA profile probably by modulating relative abundances of gut microbial genera that play key roles in BA metabolism and might consequently impact glucose homoeostasis. The detrimental effect of LCA on nutrient transport in enterocytes might be aggravated under LPS challenge.
The current study aimed to evaluate the association of major dietary patterns with anxiety in middle-aged adults in eastern China.
Dietary intake was assessed using a semi-quantitative FFQ. Binary logistic regression analysis was used to estimate OR and 95 % CI for anxiety according to quartiles of each dietary pattern score.
Evidence regarding the relationship between dietary patterns and anxiety in the Chinese population is scarce.
The study participants were 1360 Chinese adults aged 45–59 years, who participated in a health survey at the time of periodic check-up in the city of Linyi, Shandong Province, China.
Four major dietary patterns were identified by factor analysis: traditional Chinese, western, grains–vegetables and high-salt diets. After adjusting for potential confounders, participants in the highest quartile of the western pattern had greater odds for anxiety, compared with those in the lowest quartile (OR 1·35, 95 % CI 1·000, 3·086, P < 0·05). In contrast, participants in the highest quartile of the grains–vegetables pattern had lower odds for anxiety than did those in the lowest quartile (OR 0·78, 95 % CI 0·574, 1·000, P < 0·05). Moreover, no significant associations were observed between the traditional Chinese and high-salt patterns and the risk of anxiety.
Our findings indicate that the western pattern is associated with an increased risk, and the grains–vegetables pattern is associated with a decreased risk of anxiety.
We present a long-term seasonal tree ring cellulose oxygen isotope (δ18Oc) time series created by analyzing four segments (S1, S2, S3, and S4) per year during the period of 1951–2009 from southeastern Tibetan Plateau. This intraseasonal δ18Oc reveals the onset and mature phase of the summer monsoon precipitation in this region. Analysis indicates that the δ18Oc of S1 has the strongest correlation with precipitation during the regional monsoon onset (29–33 pentads, May 21–June 10, r = −0.69), and the δ18Oc values for S2, S3, and S4 correlate strongly with June, July, and August precipitation, respectively. Combined δ18Oc of S2, S3, and S4 shows the most robust correlation (r = −0.82) with the mature-phase monsoon precipitation (June-July-August, JJA), passing rigorous statistical tests for calibration and verification in dendroclimatology. These results demonstrate the feasibility in using long-term intraseasonal δ18Oc to reconstruct the Asian summer monsoon's intraseasonal variations.
We investigate the phased evolution and variation of the South Asian monsoon and resulting weathering intensity and physical erosion in the Himalaya–Karakoram Mountains since late Pliocene time (c. 3.4 Ma) using a comprehensive approach. Neodymium and strontium isotopic compositions and single-grain zircon U–Pb age spectra reveal the sources of the deposits in the east Arabian Sea, and show a combination of sources from the Himalaya and the Karakoram–Kohistan–Ladakh Mountains, with sediments from the Indian Peninsula such as the Deccan Traps or Craton. We interpret shifts in the sediment sources to have been forced by sea-level changes that correlate with South Asian monsoon rainfall variation since late Pliocene time. We collected 908 samples from the International Ocean Discovery Program Hole U1456A, which was drilled in the east Arabian Sea. Time series of hematite content and grain size of the sediments were examined downcore. We found South Asian monsoon precipitation and weathering intensity experienced three phases from late Pliocene time. Lower monsoon precipitation, with a lower variability and strong weathering intensity, occurred during 3.4–2.4 Ma; an increased and more variable South Asian monsoon rainfall, along with strengthened but fluctuating weathering intensity, occurred at 1.8–1.1 Ma; and a reduced rainfall with lower South Asian monsoon precipitation variability and moderate weathering intensity marked the period 1.1–0.1 Ma. Maximum entropy spectral analysis and wavelet transform show that there were orbital-dominated cycles of periods c. 100 and c. 41 ka in these proxy-based time series. We propose that the monsoon, sea level, global temperature and insolation together forced the weathering and erosion in SW Asia.
In the present work, an efficient route has been further explored to achieve the batch synthesis of inorganic fullerene (IF)-WS2 nanoparticles, and the self-lubricating film is conveniently prepared by coating these nanoparticles on the surface of metal substrates. The as-synthesized IF-WS2 nanoparticles have a closed hollow structure with an average particle size of about 50 nm and are evenly distributed in the self-lubricating film. Further friction tests show that the film has excellent friction properties, with its lowest friction coefficient of approximately 0.008, which can be mainly attributed to the unique hollow cage structure and a smaller particle size of the IF-WS2 nanoparticles.
Although alienation toward parents is important for children (for current mental health status or later interpersonal relationships in adulthood), it is undervalued and even lacks a standardized tool of assessment. Moreover, the large number of left-behind children in China is a cause of public concern. However, their experienced alienation toward their parents remains unclear, which may be important for early detection or intervention for behavioral problems in this population. Hence, the current study aimed to develop an alienation inventory for children and then use it to investigate the experienced alienation toward parents in Chinese left-behind children.
Two studies were carried out. Study 1 was designed to develop a standard inventory of alienation toward parents (IAP). In study 2, 8361 children and adolescents (6704 of them were left-behind status) of the Chongqing area, aged between 8 and 19 years old, were recruited for investigation. All participants were surveyed with a standard sociodemographic questionnaire, children's cognitive style questionnaire, children's depression inventory, adolescent self-rating life events checklist, and newly built IAP in study 1.
In study 1, we developed a two-component (communication and emotional distance) and 18-item (9 items for maternal or paternal form, respectively) IAP questionnaire. In study 2, exploratory factor analysis indicated an expected two-factor structure of IAP, which was confirmed by confirmatory factor analysis. The Cronbach's alpha coefficients showed a good reliability (0.887 and 0.821 for maternal and paternal form, respectively). Children with absent mother experienced the highest alienation toward parents. Boys as well as children aged 8–10 years old experienced higher alienation toward parents. Poor communication with parents (sparse or no connection), level of left-behind condition (parents divorced, been far away from parents), and psychosocial vulnerability (stressful life events, negative cognitive style) were risk factors of alienation toward parents.
The current study develops a two-factor (communication and emotional distance) IAP, which offers a reliable tool to assess experienced alienation of affection toward parents in children aged between 8 and 19 years old. Our result is the first investigation of experienced alienation and potential influential factors in Chinese left-behind children. The findings that children with absent mother experience higher alienation toward parents, as well as three recognized risk factors for alienation of affection toward parents (poor communication with absent parents, worse left-behind condition, and psychosocial vulnerability), give valuable guidance for parents who intend to leave or who are already leaving as well as for government policymaking.
The coronal heating problem is a long-standing perplexing issue. In this study, 13 solar activity indexes are used to investigate their phase relation with the sunspot number (SSN). Only three of them are found to statistically significantly lag the SSN (large-scale magnetic activity) by about one solar rotation period; the three indexes are total solar irradiance (TSI), the modified coronal index, and the solar wind velocity; the former two indexes may represent the long-term variation of energy quantity of the heated photosphere and corona, respectively. The Mount Wilson Sunspot Index (MWSI) and the Magnetic Plage Strength Index (MPSI), which reflect the large- and small-scale magnetic field activities, respectively, are also utilised to investigate their phase relations with the three indexes. The three indexes are found to be much more intimately related to MPSI than to MWSI, and MWSI statistically significantly leads TSI by about one rotation period. The heated corona is found to pulse perfectly in step with the small-scale magnetic activity rather than the large-scale magnetic activity; furthermore, combined with observations, our statistical evidence should thus attribute coronal heating firmly to small-scale magnetic activity phenomena, such as spicules, micro-flares, nano-flares, and others. The photosphere and the corona are synchronously heated, which should seemingly prefer magnetic reconnection heating to wave heating. In the long term, such a coronal heating way is inferred effective. Statistically, it is also small-scale magnetic activity phenomena that produce TSI enhancement. Coronal heating and solar wind acceleration are found to be synchronous, as standard models require.
This study aimed to examine the efficacy of combining paroxetine and mirtazapine v. switching to mirtazapine, for patients with major depressive disorder (MDD) who have had an insufficient response to SSRI monotherapy (paroxetine) after the first 2 weeks of treatment.
This double-blind, randomized, placebo-controlled, three-arm study recruited participants from five hospitals in China. Eligible participants were aged 18–60 years with MDD of at least moderate severity. Participants received paroxetine during a 2-week open-label phase and patients who had not achieved early improvement were randomized to paroxetine, mirtazapine or paroxetine combined with mirtazapine for 6 weeks. The primary outcome was improvement on the Hamilton Rating Scale for Depression 17-item (HAMD-17) scores 6 weeks after randomization.
A total of 204 patients who showed early non-response to paroxetine monotherapy were randomly assigned to receive either mirtazapine and placebo (n = 68), paroxetine and placebo (n = 68) or mirtazapine and paroxetine (n = 68), with 164 patients completing the outcome assessment. At week 8, the least squares (LS) mean change of HAMD-17 scores did not significantly differ among the three groups, (12.98 points) in the mirtazapine group, (12.50 points) in the paroxetine group and (13.27 points) in the mirtazapine plus paroxetine combination group. Participants in the paroxetine monotherapy group were least likely to experience adverse effects.
After 8 weeks follow-up, paroxetine monotherapy, mirtazapine monotherapy and paroxetine/mirtazapine combination therapy were equally effective in non-improvers at 2 weeks. The results of this trial do not support a recommendation to routinely offer additional treatment or a switch in treatment strategies for MDD patients who do not show early improvement after 2 weeks of antidepressant treatment.
The experiment was conducted to investigate the effects of dietary threonine (Thr) on growth performance and muscle growth, protein synthesis and antioxidant-related signalling pathways of hybrid catfish Pelteobagrus vachelli♀ × Leiocassis longirostris♂. A total of 1200 fish (14·19 (se 0·13) g) were randomly distributed into six groups with four replicates each, fed six diets with graded level of Thr (9·5, 11·5, 13·5, 15·4, 17·4 and 19·3 g/kg diets) for 56 d. Results showed (P < 0·05) that dietary Thr (1) increased percentage weight gain, specific growth rate, feed efficiency and protein efficiency ratio; (2) up-regulated growth hormone (GH), insulin-like growth factor 1 (IGF-1), proliferating cell nuclear antigen, myogenic regulation factors (MyoD, Myf5, MyoG and Mrf4) and myosin heavy chain (MyHC) mRNA levels; (3) increased muscle protein content via regulating the protein kinase B/target of rapamycin signalling pathway and (4) decreased malondialdehyde and protein carbonyl contents, increased catalase, glutathione-S-transferase, glutathione reductase and GSH activities, up-regulated mRNA levels of antioxidant enzymes related to NFE2-related factor 2 and γ-glutamylcysteine ligase catalytic subunit. These results suggest that Thr has a potential role to improve muscle growth and protein synthesis, which might be due to the regulation of GH-IGF system, muscle growth-related gene, antioxidative capacity and protein synthesis-related signalling pathways. Based on the quadratic regression analysis of specific growth rate, the Thr requirement of hybrid catfish (14·19–25·77 g) was estimated to be 13·77 g/kg of the diet (33·40 g/kg of dietary protein).
This study seeks to identify healthcare utilization patterns following symptomatic respiratory tract infections (RTIs) and the variables that may influence these patterns.
RTIs are responsible for the bulk of the primary healthcare burden worldwide. Yet, the use of health services for RTIs displays great discrepancies between populations. This research examines the influence of social demographics, economic factors, and accessibility on healthcare utilization following RTIs.
Structured interviews were administered by trained physicians at the households of informants selected by cluster randomization. Descriptive and multivariate binary logistic regression analysis was performed to assess healthcare utilization and associated independent variables.
A total of 60 678 informants completed the interviews. Of the 2.9% informants exhibiting upper RTIs, 69.5–73.9% sought clinical care. Healthcare utilization rates for common cold, influenza, nine acute upper RTIs, and overall RTIs demonstrate statistically significant associations with the variables of age, type of residence, employment, medical insurance, annual food expenditure, distance to medical facilities, and others. The odds ratios for healthcare utilization rates varied substantially, ranging from 0.026 to 9.364. More than 69% of informants with RTIs sought clinical interventions. These findings signify a marked issue with the large amount of healthcare for self-limited RTIs.
Synaptotagmin 1 (Syt1) is an abundant and important presynaptic vesicle protein that binds Ca2+ for the regulation of synaptic vesicle exocytosis. Our previous study reported its localization and function on spindle assembly in mouse oocyte meiotic maturation. The present study was designed to investigate the function of Syt1 during mouse oocyte activation and subsequent cortical granule exocytosis (CGE) using confocal microscopy, morpholinol-based knockdown and time-lapse live cell imaging. By employing live cell imaging, we first studied the dynamic process of CGE and calculated the time interval between [Ca2+]i rise and CGE after oocyte activation. We further showed that Syt1 was co-localized to cortical granules (CGs) at the oocyte cortex. After oocyte activation with SrCl2, the Syt1 distribution pattern was altered significantly, similar to the changes seen for the CGs. Knockdown of Syt1 inhibited [Ca2+]i oscillations, disrupted the F-actin distribution pattern and delayed the time of cortical reaction. In summary, as a synaptic vesicle protein and calcium sensor for exocytosis, Syt1 acts as an essential regulator in mouse oocyte activation events including the generation of Ca2+ signals and CGE.
This study explored how internet queries vary in facilitating monitoring of pertussis, and the effects of sociodemographic characteristics on such variation by city in Shandong province, China. We collected weekly pertussis notifications, Baidu Index (BI) data and yearly sociodemographic data at the city level between 1 January 2009 and 31 December 2017. Spearman's correlation was performed for temporal risk indices, generalised linear models and regression tree models were developed to identify the hierarchical effects and the threshold between sociodemographic factors and internet query data with pertussis surveillance. The BI was correlated with pertussis notifications, with a strongly spatial variation among cities in temporal risk indices (composite temporal risk metric (CTRM) range: 0.59–1.24). The percentage of urban population (relative risk (RR): 1.05, 95% confidence interval (CI) 1.03–1.07), the proportion of highly educated population (RR: 1.27, 95% CI 1.16–1.39) and the internet access rate (RR: 1.04, 95% CI 1.02–1.05) were correlated with CTRM. Higher RRs in the three identified sociodemographic factors were associated with higher stratified CTRM. The percentage of highly educated population was the most important determinant in the BI with pertussis surveillance. The findings may lead to spatially-specific criteria to inform development of an early warning system of pertussis infections using internet query data.
The microbiota–gut–brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients.
We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD.
The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890.
The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.
Maternal supraphysiological estradiol (E2) environment during pregnancy leads to adverse perinatal outcomes. However, the influence of oocyte exposure to high E2 levels on perinatal outcomes remains unknown. Thus, a retrospective cohort study was conducted to explore the effect of high E2 level induced by controlled ovarian stimulation (COH) on further outcomes after frozen embryo transfer (FET). The study included all FET cycles (n = 10,581) between 2014 and 2017. All cycles were categorized into three groups according to the E2 level on the day of the human Chorionic Gonadotropin trigger. Odds ratios (ORs) and their confidence intervals (CIs) were calculated to evaluate the association between E2 level during COH and pregnancy outcomes and subsequent neonatal outcomes. From our findings, higher E2 level was associated with lower percentage of chemical pregnancy, clinical pregnancy, ongoing pregnancy, and live birth as well as increased frequency of early miscarriage. Preterm births were more common among singletons in women with higher E2 level during COH (aOR1 = 1.93, 95% CI: 1.22–3.06; aOR2 = 2.05, 95% CI: 1.33–3.06). Incidence of small for gestational age (SGA) was more common in both singletons (aOR1 = 2.01, 95% CI: 1.30–3.11; aOR2 = 2.51, 95% CI: 1.69–3.74) and multiples (aOR1 = 1.58, 95% CI: 1.03–2.45; aOR2 = 1.99, 95% CI: 1.05–3.84) among women with relatively higher E2 level. No association was found between high E2 level during COH and the percentage of macrosomia or large for gestational age. In summary, oocyte exposure to high E2 level during COH should be brought to our attention, since the pregnancy rate decreasing and the risk of preterm birth and SGA increasing following FET.
Repetitive motion planning and control (RMPC) is a significant issue in the research of redundant robot manipulators. Moreover, noise from rounding error, truncation error, and robot uncertainty is an important factor that greatly affects RMPC schemes. In this study, the RMPC of redundant robot manipulators in a noisy environment is investigated. By incorporating the proportional and integral information of the desired path, a new RMPC scheme with pseudoinverse-type (P-type) formulation is proposed. Such a P-type RMPC scheme possesses the suppression of constant and bounded time-varying noises. Comparative simulation results based on a five-link robot manipulator and a PUMA560 robot manipulator are presented to further validate the effectiveness and superiority of the proposed P-type RMPC scheme over the previous one.
Permian faunal affinity in the Lhasa Block plays a critical role in reconstructing its paleogeographic evolution. Cisuralian and Guadalupian faunas have been described from the Lhasa Block, but very few Lopingian (late Permian) brachiopods have been reported so far. In this paper, a new diverse brachiopod fauna consisting of 17 species of 17 genera and an unidentifiable Orthotetoidea is described from the uppermost part of the Xiala Formation at the Aduogabu section in the central part of the Lhasa Block. The age of this fauna can be assigned to the Changhsingian (late Lopingian) as indicated by the associated foraminifers Colaniella parva (Colani, 1924) and Reichelina pulchra Miklukho-Maklay, 1954. Characteristic brachiopods include Spinomarginifera chengyaoyenensis Huang, 1932, Haydenella wenganensis (Huang, 1932), and Araxathyris cf. dilatatus Shen, He, and Zhu, 1992. They also generally suggest a Changhsingian age. Paleobiogeographically, this fauna is uniformly composed of typical Tethyan elements represented by Spinomarginifera Huang, 1932 and Haydenella Reed, 1944, and some cosmopolitan elements, but no typical cold-water taxa of Gondwanan affinity. This is in contrast to the contemporaneous brachiopod faunas from the Tethys Himalayan region that are characterized by typical cold-water taxa of Gondwanan affinity, e.g., Costiferina indica (Waagen, 1884), Retimarginifera xizangensis Shen et al., 2000, Neospirifer (Quadrospina) tibetensis Ding, 1962. Thus, it is strongly indicative that the Lhasa Block had drifted into a relatively warm-water regime during the Changhsingian. An analysis of the paleobiogeographic change of brachiopods in the Lhasa Block throughout the entire Permian further suggests that the Lhasa Block probably had rifted away from the northern peri-Gondwanan margin between the latest Cisuralian and middle Guadalupian, that is, the Neotethys Ocean had opened before middle Guadalupian.
Swelling deformation tests of Kunigel bentonite and its sand mixtures were performed in distilled water and NaCl solution. The salinity of NaCl solution has a significant impact on the swelling properties of bentonite, but not on its surface structure. The surface structure was characterized using the fractal dimension Ds. Based on the fractal dimension, a unique curve of the em–pe relationship (em is the void ratio of montmorillonite and pe is the effective stress) at full saturation was introduced to express the swelling deformation of bentonite–sand mixtures. In mixtures with a large bentonite content, the swelling deformation always followed the em–pe relationship. In mixtures with a small bentonite content, when the effective stress reached a threshold, the void ratio of montmorillonite em deviated from the unique em–pe curve due to the appearance of a sand skeleton. The threshold of vertical pressure for mixtures in different solutions and the maximum swelling strains were estimated using the em–pe relationship. The good agreement between estimates and experimental data suggest that the em–pe relationship might be an alternative method for predicting the swelling deformation of bentonite–sand mixtures in salt solution.
Paediatric Mycoplasma pneumoniae pneumonia (MPP) is a major cause of community-acquired pneumonia in China. Data on epidemiology of paediatric MPP from China are little known. This study retrospectively collected data from June 2006 to June 2016 in Beijing Children's Hospital, Capital Medical University of North China and aims to explore the epidemiological features of paediatric MPP and severe MPP (SMPP) in North China during the past 10 years. A total of 27 498 paediatric patients with pneumonia were enrolled. Among them, 37.5% of paediatric patients had MPP. In this area, an epidemic took place every 2–3 years at the peak, and the positive rate of MPP increased during these peak years over time. The peak age of MPP was between the ages of 6 and 10 years, accounting for 75.2%, significantly more compared with other age groups (χ2 = 1384.1, P < 0.0001). The epidemics peaked in September, October and November (χ2 = 904.9, P < 0.0001). Additionally, 13.0% of MPP paediatric patients were SMPP, but over time, the rate of SMPP increased, reaching 42.6% in 2016. The mean age of paediatric patients with SMPP (6.7 ± 3.0 years old) was younger than that of patients with non-SMPP (7.4 ± 3.2 years old) (t = 3.60, P = 0.0001). The prevalence of MPP and SMPP is common in China, especially in children from 6 to 10 years old. Paediatric patients with SMPP tend to be younger than those with non-SMPP. MPP outbreaks occur every 2–3 years in North China. September, October and November are the peak months, unlike in South China. Understanding the epidemiological characteristics of paediatric MPP can contribute to timely treatment and diagnosis, and may improve the prognosis of children with SMPP.