Porphyromonas gingivalis-derived lipopolysaccharide causes excessive hepatic lipid accumulation via activating NF-κB and JNK signaling pathways.

BACKGROUND: Porphyromonas gingivalis is the main pathogen of periodontal disease affecting over half of the worldwide adult population. Recent studies have shown that P. gingivalis is related to the development of non-alcoholic fatty liver disease (NAFLD), a global major chronic liver disease, especially in developed countries. However, how P. gingivalis contributes to the pathogenesis of NAFLD has not been fully clarified. We aimed to conduct a preliminary exploration of the underlying mechanism of P. gingivalis infection in the development of NAFLD. METHODS: Human hepatocellular cells HepG2 were incubated with/without oleic acid (OA) and tested for lipid accumulation upon stimulation by lipopolysaccharide (LPS) derived from P. gingivalis or Escherichia coli. Intracellular lipid droplet formation was analyzed and quantified by Oil Red O staining. The involvement of signaling pathway molecules and pro-inflammatory cytokines related to NF-κB and MAPKs were examined with Western blot and quantitative real-time PCR (qRT-PCR) analyses and further evaluated with inhibitor treatment and RNA interference. RESULTS: HepG2 cells accumulated more intracellular lipids when stimulated with P. gingivalis LPS, as compared to cells treated with E. coli LPS or control. Further pathway analysis demonstrated that after stimulation with P. gingivalis LPS, cells displayed significantly upregulated MyD88 expression, increased phosphorylation of p65 and JNK, and more release of pro-inflammatory cytokines, such as IL-1, IL-8, and TNF-α. In addition, suppression of phosphorylation of p65 and JNK by inhibitors and RNA interference resulted in a reduction in lipid accumulation upon P. gingivalis LPS treatment. CONCLUSIONS: These results suggest that P. gingivalis-derived LPS may contribute to intracellular lipid accumulation and inflammatory reaction of HepG2 cells via the activation of NF-κB and JNK signaling pathways. This study offers a possible explanation to the functional involvement of P. gingivalis infection in the pathological progression of NAFLD. These findings may help design new treatment strategies in NAFLD.

The relationship between children's oral health-related behaviors and their caregiver's social support.

BACKGROUND: Social support might play a role in helping people adopt healthy behaviors and improve their health. Stronger social support from mothers has been found to be positively related to higher tooth brushing frequency in 1- to 3-year-old children. However, little is known regarding the relationship between the caregiver's social support and the oral health-related behaviors of 5-year-old children in China. This study aimed to investigate this relationship. METHODS: A cross-sectional study was conducted among 1332 5-year-old children and their caregivers in Guangzhou, southern China. Data were collected using questionnaires that were completed by the caregivers and the children's caries status were examined. The caregivers' social support was measured using the Social Support Rating Scale. The measurements of the children's oral health-related behaviors included the frequencies of sugary snack intake and tooth brushing, utilization of dental services, and patterns of dental visits. Univariate and multiple logistic regression analyses were used to analyze the relationships between the variables. RESULTS: No association was found between the caregiver's social support and the child's oral health-related behaviors in a multiple logistic regression analysis. However, other factors, particularly the oral health-related behaviors of the caregiver, were found to be significantly linked to the child's oral health-related behaviors. CONCLUSIONS: The oral health-related behaviors of 5-year-old children in Guangzhou are unrelated to the caregiver's social support but are related to other specific factors, particularly the caregiver's oral health-related behaviors.

Genetic polymorphisms of the sortase A gene and social-behavioural factors associated with caries in children: a case-control study.

BACKGROUND: Streptococcus mutans (S. mutans) is the primary etiological agent of dental caries. Sortase is a transpeptidase that anchors several surface proteins to the S. mutans cell wall and has been shown to play a major role in cariogenicity. The purpose of this study was to explore the genetic polymorphisms of the sortase gene (srtA) and the social-behavioural factors associated with dental caries in children with S. mutans. METHODS: In this case-control study, 121 S. mutans strains were separately selected from caries-free children and high-severity caries children for sequencing of the srtA gene. Social and behavioural data were collected by self-administered questionnaires. Genomic DNA was extracted from S. mutans strains and amplified by PCR to obtain the srtA gene. The purified PCR products were sequenced and analysed for mutations with ABI Variant Reporter software. The distribution of missense mutations and the mean of social-behavioural factors were compared between the groups. A multiple logistic regression model was used to control for confounding factors. RESULTS: The mutation frequencies at loci 168 (P = 0.023) and 470 (P = 0.032) were significantly different between the groups. The best-fitting model showed that greater age, high frequencies of solid sugar consumption, prolonged breastfeeding, a high proportion of visible plaque, and S. mutans with a T at locus 168 of the srtA gene were associated with high-severity caries in children (P < 0.05). Children carrying a G at locus 168 of S. mutans had a decreased risk for high-severity caries (OR = 0.32, 95% CI = 0.12-0.86) compared with those carrying a T. CONCLUSIONS: The present study suggested that the locus 168 missense mutation of the srtA gene may correlate with caries susceptibility in children with S. mutans. In addition, age, duration of breastfeeding, solid sugar consumption, and poor oral hygiene contributed to this complex disease.

Factors related to children's caries: a structural equation modeling approach.

BACKGROUND: Dental caries among preschool children is highly prevalent in many less-developed countries. METHODS: A model which explored the factors related to children's dental caries was tested in this study using structural equation modeling. Caregivers of children aged 5 years were surveyed on their socioeconomic status, and their oral health knowledge, attitudes and practices. In addition, information on their children's oral health practices, dental insurance and dental service utilization were collected. Examination of caries was conducted on all children who returned fully completed questionnaires. RESULTS: The results showed that socioeconomic factors influenced children's oral health practices through the impact of caregivers' oral health knowledge and practices; that caregivers' oral health knowledge affected children's oral health practices through the influence of caregivers' oral health attitudes and practices; and finally, that children's oral health practices were linked directly to their caries. CONCLUSION: The findings have important applications for promoting policies aimed at advancing children's oral health.

Relationship between children's oral health-related behaviors and their caregiver's sense of coherence.

BACKGROUND: Sense of coherence (SOC) is hypothesized to be an important psychological factor that enables people to cope with stressors and successfully maintain and improve health. Mother's SOC has been shown to be an important psychological factor associated with oral health and oral health-related behaviors of adolescents and 11- to 12-year-old children. However, little is known about the relationship between the caregiver's SOC and oral health-related behaviors of the preschool children. The objective of this study was to investigate the relationship between oral health-related behaviors of 5-year-old children in Southern China and SOC of their caregiver. METHODS: A cross-sectional study was conducted in a randomized sample of 1332 children aged 5 years and their caregivers in Guangzhou, Southern China. Data were collected through questionnaires completed by the caregivers. The Chinese short version of Antonovsky's SOC scale (13 items) was employed to assess the caregiver's SOC. The outcome variables were the child's oral health-related behaviors, including frequency of sugary snack intake, toothbrushing frequency, utilization of dental service, and pattern of dental visits. Multiple logistic regression was used to analyze the relationship between the variables. RESULTS: No association was found between the children's sugary snack intake and the mother's or the father's SOC. After adjustment for other significant factors related to the child's oral health-related behaviors, 8.9% of the children whose grandparents (as caregivers) had higher SOC scores had a lower frequency of sugary snack intake, compared with the children whose grandparents had lower SOC scores (OR = 0.61, 95% CI = 0.50-0.73, p = 0.008). The other measures of oral health-related behaviors of the child were not significantly associated with the caregiver's SOC. CONCLUSION: Sugary snack intake behavior of the 5-year-old children was not associated with the mother's or the father's SOC. It was associated with the SOC of their grandparents, who are a small group of the caregivers in China.

Genome sequence of Paenibacillus sp. strain Aloe-11, an endophytic bacterium with broad antimicrobial activity and intestinal colonization ability.

Paenibacillus sp. strain Aloe-11, a Gram-positive, spore-forming, facultatively anaerobic bacterium isolated from the root of Aloe chinensis in the southwest region of China, has excellent antibiotic activity and intestine colonization ability. Here, we present the 5.8-Mb draft genome sequence of Paenibacillus sp. strain Aloe-11.

Biodegradation and disintegration of expanded polystyrene by land snails Achatina fulica.

Despite increasing evidence of widespread plastic pollution in soil, it remains largely unknown about the fate of plastic influenced by soil animals. In this study, ingestion and biodegradation capability of expanded polystyrene (PS) foam was investigated in a globally distributed soil invertebrate, Achatina fulica. After 4-week exposure, 18.5 ± 2.9 mg polystyrene was ingested per snail, and egested microplastics (1.343 ± 0.625 mm) in feces with significant mass loss of mean 30.7%. Gel permeation chromatography analysis indicated a significant increase in weight-average molecular weight (Mw) and number-average molecular weight (Mn) of feces-residual PS, indicating limited extent depolymerization. Fourier transform infrared spectroscopy and proton nuclear magnetic resonance confirmed the formation of functional groups of oxidized intermediates. Suppression of gut microbes with oxytetracycline did not affect the depolymerization, indicating the independence of gut microbes. High-throughput sequencing analysis revealed significant shifts in the gut microbiome after ingestion of PS, with an increase of family Enterobacteriaceae, Sphingobacteriaceae, and Aeromonadaceae, suggesting that gut microorganisms were associated with PS biodegradation. These findings suggest that plastic litter can be disintegrated into microplastics and partially biodegraded by A. fulica, which highlights the significance of soil animals for the fate of plastic and its biodegradation in soil environments.

Prevalence of microplastics in animal-based traditional medicinal materials: Widespread pollution in terrestrial environments.

Microplastics (MPs) pollution is an emerging environmental and health concern. MPs have been extensively observed in the aquatic environment, yet rarely investigated in the terrestrial ecosystem, especially in relation to health risks. To evaluate potential MPs pollution in land-dwelling animal medicine materials, we collected 20 types of small animal-based medicinal materials and 10 types of available fresh terrestrial animals from eight different regions in China. MPs were found in all medicinal materials with an average incidence rate of 94.67%. The abundance of MPs was in the range of 1.80 ± 0.38 to 7.80 ± 0.83 items/individual or 1.59 ± 0.33 to 43.56 ± 9.22 items/g (dry weight), with polymer distribution by polyethylene terephthalate (40.45%), rayon (30.64%), polyethylene (10.11%), nylon (7.35%), polypropylene (5.93%), and polyvinyl chloride (5.52%). The majority of MPs were microfibers (84.68%), with 15.32% of fragments. Moreover, MPs were directly observed in the intestine, detected in all ten types of fresh medicinal animals with the abundance of 0.83 ± 0.35 to 3.42 ± 0.46 items/individual. Furthermore, significant positive correlations (R: 0.32-0.99, p < 0.05) of MPs characteristics were found between medicinal materials and fresh animals, including shape, size, color, and polymer distribution of MPs. The results support that MPs in the medicinal materials were likely derived from living animals. This study demonstrates the prevalence of MPs in animal-based, traditional medicinal materials, and also suggests widespread MPs pollution in terrestrial environments and latent health risks.

Uptake and adverse effects of polyethylene terephthalate microplastics fibers on terrestrial snails (Achatina fulica) after soil exposure.

Recent studies have demonstrated the occurrence of microplastic fibers (MFs) in soil environments. To determine whether MFs are harmful for soil biota, we evaluated toxic effects on terrestrial snails (Achatina fulica) after 28 d exposure to polyethylene terephthalate MFs at concentrations of 0.01-0.71 g kg-1 (dry soil weight). Digestion kinetics experiments on 24 snails showed that MFs can be ingested and excreted within 48 h. We found the appearance of cracks and deterioration on the surface of MFs after depuration by the digestive system. Prolonged exposure to 40 snails showed that 0.14-0.71 g kg-1 MFs caused an average reduction of 24.7-34.9% food intake and 46.6-69.7% excretion. 0.71 g kg-1 MFs induced significant villi damage in the gastrointestinal walls of 40% snails, but did not influence the histology of the liver and kidney. Moreover, 0.71 g kg-1 MFs exposure reduced glutathione peroxidase (59.3 ±â€¯13.8%) and total antioxidant capacity (36.7 ±â€¯8.5%), but elevated malondialdehyde level (58.0 ±â€¯6.4%) in the liver, which indicates oxidative stress is involved in the toxic mechanism. Our results suggest that MFs have adverse impacts on the fitness of soil organisms, and highlight the ecological risks of microplastic pollution in terrestrial ecosystems.

Preliminary investigation of seeding mesenchymal stem cells on biodegradable scaffolds for vascular tissue engineering in vitro.

We used epsilon-caprolactone/L-lactide (PCLA) as a biodegradable scaffold and bone marrow (BM) mesenchymal stem cells (MSCs) as seeding cells for vascular tissue engineering: we expected MSCs to grow in the scaffolds in a bioreactor. The MSCs we used were from the BM of dogs, and vascular scaffolds were carried out on the electrospinning process of PCLA copolymers. MSCs expressed CD44 and CD105 but did not express CD34 or CD14 at an identical time point. Scaffolds were nontoxic to cells and were favorable for the growth and migration of MSCs. After culture in a bioreactor with mechanical stimulation, cells completely covered the surfaces of PCLA scaffolds and penetrated or infiltrated into the inside of the scaffold structure.

Electrospinning of synthesized triblock copolymers of epsilon-caprolactone and L-lactide for the application of vascular tissue engineering.

Biodegradable triblock copolymers of epsilon-caprolactone and L-lactide with varying compositions and molecular weights have been synthesized. They were then used to fabricate compliant small-diameter tissue engineered vascular scaffolds by using an electrospinning technique. The in vitro and in vivo degradation of the ultrafine fabrics was monitored to be faster than their counterpart cast films. A favorable interaction between the scaffolds and the mouse fibroblast L929 cells was demonstrated via MTT assay. A confluent, adherent monolayer of canine mesenchymal stem cells was observed in the tubular scaffold lumen after culture in a bioreactor for 3 days. The scaffold mechanical strength was strong enough to be transplanted into the canine carotid artery.