Fighting bacteria with bacteria: A biocompatible living hydrogel patch for combating bacterial infections and promoting wound healing.

Bacterial infections are among the most critical global health challenges that seriously threaten the security of human. To address this issue, a biocompatible engineered living hydrogel patch was developed by co-embedding engineered photothermal bacteria (EM), photosensitizer (porphyrin) and reactive oxygen species amplifier (laccase) in a protein hydrogel. Remarkably, the genetice engineered bacteria can express melanin granules in vivo and this allows them to exhibit photothermal response upon being exposed to NIR-II laser (1064 nm) irradiation. Besides, electrostatically adhered tetramethylpyridinium porphyrin (TMPyP) on the bacterial surface and encapsulated laccase (Lac) in protein gel can generate highly toxic singlet oxygen (1O2) and hydroxyl radical (·OH) in the presence of visible light and lignin, respectively. Interestingly, the engineered bacteria hydrogel patch (EMTL@Gel) was successfully applied in synergistic photothermal, photodynamic and chemodynamic therapy, in which it was able to efficiently treat bacterial infection in mouse wounds and enhance wound healing. This work demonstrates the concept of "fighting bacteria with bacteria" combining bacterial engineering and material engineering into an engineered living hydrogel path that can synergistically boost the therapeutic outcome. STATEMENT OF SIGNIFICANCE: Genetically engineered bacteria produce melanin granules in vivo, exhibiting remarkable photothermal properties. These bacteria, along with a photosensitizer (TMPyP) and a reactive oxygen species amplifier (laccase), are incorporated into a biocompatible protein hydrogel patch. Under visible light, the patch generates toxic singlet oxygen (1O2) and hydroxyl radical (·OH), demonstrates outstanding synergistic effects in photothermal, photodynamic, and chemodynamic therapy, effectively treating bacterial infections and promoting wound healing in mice.

Association between Periodontitis and Aortic Calcification: A Cohort Study.

The present study investigated the association between the presence of periodontitis and aortic calcification (AC) risk among Chinese adults. A total of 6059 individuals who underwent regular health check-ups and received a diagnosis of periodontitis between 2009 and 2016 were included. The outcome was AC, assessed by a chest low-dose spiral CT scan. Cox proportional hazards regression analysis was used to assess the association between periodontitis and AC risk after adjusting for several confounders. After a median follow-up period of 2.3 years (interquartile range: 1.03-4.97 years), 843 cases of AC were identified, with 532 (12.13%) and 311 (18.59%) patients in the non-periodontitis group and periodontitis group, respectively. Multivariate analyses demonstrated that, compared with those without periodontitis, the hazard ratio and 95% confidence interval for AC risk in participants with periodontitis was 1.18 (1.02-1.36) (P = .025) in the fully adjusted model. Stratified analyses showed that the positive relationship between periodontitis and AC was more evident in males and participants <65 years of age (pinteraction = .005 and .004, respectively). Our results show that the presence of periodontitis was positively associated with AC among Chinese adults, especially among males and younger participants.

Selective adsorption of antibiotics on aged microplastics originating from mariculture benefits the colonization of opportunistic pathogenic bacteria.

Microplastics and antibiotics widely coexist in the aquatic environment, especially in mariculture regions. However, antibiotics adsorbed on microplastics and their role in the colonization of microorganisms on microplastics are poorly understood. Therefore, in-situ aging experiments were conducted to investigate the impact of antibiotics and microplastics co-occurrence on microorganisms and assess their potential risks to human health. Results showed that antibiotics were adsorbed selectively on microplastics, with 29 investigated antibiotics (n = 40) detected in surrounding water but only 6 investigated antibiotics were adsorbed on microplastics. The concentration of antibiotics accumulated on microplastics was controlled by microplastic types and environmental conditions. For example, aged polypropylene (PP) had more developed pore structures resulting in higher adsorption of antibiotics than other microplastic types. High-throughput sequencing showed higher diversity and distinct composition of microorganisms attached to the microplastics than the surrounding water. Opportunistic pathogenic bacteria such as Mycobacterium possessed positive relationships with tetracycline and doxycycline on aged microplastics, which showed adsorbed antibiotics on aged microplastics could benefit some specific pathogens colonized on the microplastics and spread into unaffected ecosystems, marine organisms even humans. The health risk quotient (HQ) implied the potential human health risk of consuming commercial seafood polluted by antibiotics and microplastic loaded with antibiotics. This study revealed the interaction of antibiotics and microorganisms with aged microplastics in aquaculture systems, providing a novel insight into their synergistic effects on ecological and human health.

Vertical distribution and river-sea transport of microplastics with tidal fluctuation in a subtropical estuary, China.

The river-sea transport of microplastic with complex environmental conditions and diverse driving factors has received growing attention in the estuary. This research investigated the vertical distribution of microplastics in the water column and surface sediments and explored the effect of tidal variation on the transport of microplastics in Jiulong Estuary and Xiamen Bay, China. Results show that the microplastics in the estuary (630 ± 515 µm) was significantly larger than that in the bay (344 ± 420 µm, p < 0.01). Low-density microplastics are present in the whole water column, while high-density microplastics was apt to accumulate in the bottom water and surface sediment suggesting biofouling and material density of microplastics synergistic affect its vertical distribution. Every 1-2 h high-frequency samples collected in a whole tide found the increase of fine size (45-300 µm) and decrease of large size (>300 µm) in the flood tide, which implied fine microplastics were easily driven into the estuary from the bay at flood tide than large microplastics. The abundance of microplastics in the sediments decreased in the fast-rising and fast-falling period implies the tide influences the fragmentation and resuspension of microplastics in the estuary. Finally, the flux of microplastics entering Xiamen Bay was 53.5 t/month in the moderate flow month were estimated based on the abundance of different water layers instead of floating microplastics in the surface water.

[Environmental Process, Effects and Risks of Emerging Contaminants in the Estuary-Coastal Environment].

Human activities and global climate change have contributed substantially to the input of land-sourced pollutants into the aquatic environment, especially for emerging or newly identified contaminants, such as microplastics, emerging persistent organic pollutants, pharmaceuticals, and personal care products. The prevalence and toxicity of these emerging pollutants has raised continued concern for the health and safety of the public worldwide. A review of sources, distribution, interfacial transport processes of microplastics, per-and polyfluorinated compounds, antibiotics, and endocrine-disrupting chemicals and factors that influence their environmental behavior in the estuary-coastal environment have been included. The adverse ecological effects and health risks of these emerging contaminants to humans were also reviewed. Lastly, the direction of future research was provided regarding the environmental behavior of multiple emerging pollutants in the coastal environment and the health risks resulting from their interactions, supporting the prevention and control of marine pollution and the healthy development of the marine economy.

Hygiene practices among young adolescents aged 12-15 years in low- and middle-income countries: a population-based study.

BACKGROUND: Poor personal hygiene increases disease risk, however, the prevalence of hygiene practices among adolescents is poorly described in low- and middle-income countries (LMICs). We aimed to assess the hygiene practices among young adolescents in LMICs using data from the Global School-based Student Health Surveys (GSHS). METHODS: This population-based study analysed the GSHS data for adolescents aged 12-15 years from 75 LMICs. Data were collected between 2003 and 2015 using standardised, anonymous, self-reported questionnaires. This report focuses on hygiene related behaviours such as tooth brushing, washing hands after using the toilet, washing hands before eating and washing hands with soap. The weighted prevalence and 95% confidential intervals (CIs) for the hygiene practices, and overall and regional estimates were calculated with random-effects meta-analysis. RESULTS: A total of 181 848 young adolescents from 75 LIMCs with available hygiene data were analysed. The overall prevalence for never washing hands were 7.4% (95% confidence interval (CI) = 4.4-10.3) for before eating, 5.9% (95% CI = 3.8-7.9) for after using the toilet, and 9.0% (95% CI = 6.2-11.8) for with soap. For tooth brushing, the overall prevalence estimates were 8.6% (95% CI = 5.5-11.7) for never brushing teeth, 80.9% (95% CI = 74.7-87.1) for 1-3 times per day, and 9.7% (95% CI = 5.8-13.6) for >3 times per day. However, the prevalence of different hygiene practices varied significantly among countries and regions (all P values <0.001). Poor hygiene status, with a prevalence >20%, was still observed in several LMICs (eg, 12 countries for never washing hands and 4 for never brushing teeth). CONCLUSIONS: The hygiene practices of young adolescents aged 12-15 years were generally frequent, but poor status was still observed in several LMICs. These findings emphases the need for hygiene and health education targeting young adolescents in LMICs.

Diselenium-containing ultrathin polymer nanocapsules for highly efficient targeted drug delivery and combined anticancer effect.

The combination of selenium and pillararenes to prepare selenium-containing pillararene-based biomaterials is of great significance for the development of biomedicine. Herein, using a covalent self-assembly strategy, we successfully developed new diselenium-containing ultrathin polymer nanocapsules based on lateral cross-linked pillararenes. The new system exhibited a very potent anticancer effect; additionally, the incorporation of the cleavable redox diselenium bond into the polymer nanocapsules provided a smart nanocarrier for drug delivery. Moreover, the polymer nanocapsules were developed for anticancer drug targeting delivery by loading an anticancer drug and introducing the tumor-penetrating peptide RGD through the host-guest interaction strategy. The targeting DOX-loaded diselenium-containing polymer nanocapsules exhibited enhanced stability, self-anticancer effect, targeted delivery and controlled drug release, resulting in effective combined inhibition of tumor progression.