Integrative microbiome and metabolome profiles reveal the impacts of periodontitis via oral-gut axis in first-trimester pregnant women.

BACKGROUND: Periodontitis results from host-microbe dysbiosis and the resultant dysregulated immunoinflammatory response. Importantly, it closely links to numerous systemic comorbidities, and perplexingly contributes to adverse pregnancy outcomes (APOs). Currently, there are limited studies on the distal consequences of periodontitis via oral-gut axis in pregnant women. This study investigated the integrative microbiome-metabolome profiles through multi-omics approaches in first-trimester pregnant women and explored the translational potentials. METHODS: We collected samples of subgingival plaques, saliva, sera and stool from 54 Chinese pregnant women at the first trimester, including 31 maternal periodontitis (Perio) subjects and 23 Non-Perio controls. By integrating 16S rRNA sequencing, untargeted metabolomics and clinical traits, we explored the oral-gut microbial and metabolic connection resulting from periodontitis among early pregnant women. RESULTS: We demonstrated a novel bacterial distinguisher Coprococcus from feces of periodontitis subjects in association with subgingival periodontopathogens, being different from other fecal genera in Lachnospiraceae family. The ratio of fecal Coprococcus to Lachnoclostridium could discriminate between Perio and Non-Perio groups as the ratio of subgingival Porphyromonas to Rothia did. Furthermore, there were differentially abundant fecal metabolic features pivotally enriched in periodontitis subjects like L-urobilin and kynurenic acid. We revealed a periodontitis-oriented integrative network cluster, which was centered with fecal Coprococcus and L-urobilin as well as serum triglyceride. CONCLUSIONS: The current findings about the notable influence of periodontitis on fecal microbiota and metabolites in first-trimester pregnant women via oral-gut axis signify the importance and translational implications of preconceptional oral/periodontal healthcare for enhancing maternal wellbeing.

Three-Dimensional Printed Poly (Lactic-co-Glycolic Acid)-Magnesium Composite Scaffolds for the Promotion of Osteogenesis Through Immunoregulation.

Scaffolds play an important role in bone tissue engineering. The ideal engineered scaffold needs to be biocompatible, bioactive, and able to regulate immune cells to enhance bone regeneration. In this study, magnesium (Mg)-contained poly(lactic-co-glycolic acid) (PLGA) scaffolds (hereinafter, referred to as PLGA-2Mg) were fabricated by 3-dimensional printing using a mixture of PLGA and MgSO 4 powder. Poly(lactic-co-glycolic acid) scaffolds (hereinafter, referred to as PLGA) were also fabricated by 3-dimensional printing and were used as control. The biocompatibility, immunoregulatory ability, and osteogenic properties of PLGA-2Mg were analyzed and compared with those of PLGA. The results indicate that the incorporation of Mg increased the Young modulus and surface roughness of the scaffold, but did not affect its degradation. The PLGA-2Mg further promoted the adhesion and proliferation of MC3T3-E1 cells compared with PLGA, which indicates its improved biocompatibility and bioactivity. In addition, PLGA-2Mg inhibited the polarization of RAW 264.7 cells toward the M1 phenotype by down-regulating the IL-1ß , IL-6 , and iNOs gene expression when challenged with lipopolysaccharide stimulation. In contrast, it promoted the polarization of RAW 264.7 cells toward the M2 phenotype by up-regulating the TGF-ß , IL-10 , and Arg-1 gene expression without lipopolysaccharide stimulation. Finally, MC3T3-E1 cells were cocultured with RAW 264.7 cells and scaffolds using a transwell system. It was found that the expression level of osteogenic-related genes ( ALP , COL-1 , BMP2 , and BSP ) was significantly upregulated in the PLGA-2Mg group compared with that in the PLGA group. Consequently, PLGA-2Mg with increased biocompatibility and bioactivity can promote osteogenesis through immunoregulation and has the potential to be used as a novel scaffold in bone tissue engineering.

Diagnostic performance of the AAP/EFP classification and the CDC/AAP case definition among pregnant women and a practical screening tool for maternal periodontal diseases.

BACKGROUND AND OBJECTIVE: There is a limited number of studies on the performance assessment of the 2017 AAP/EFP classification and the CDC/AAP case definition among pregnant females. This study evaluated the agreement between these two systems and explored a practical tool for screening maternal periodontal diseases by general dentists. MATERIALS AND METHODS: Totally, 204 systemically healthy females at different phases of pregnancy underwent a full-mouth periodontal examination. Demographic characteristics, lifestyles, and systemic conditions were recorded. Referring to the CDC/AAP definition, the diagnostic performance of the AAP/EFP classification was evaluated by the area under the ROC curve (AUC) and statistical tests (e.g., Youden's index and kappa coefficient). Additionally, a modified scoring system of the FDI Periodontal Diseases Chairside Guide (FDI-CG) was formulated with the addition of pregnancy for testing accordingly. RESULTS: Overall, there were 22.1% of the participants in early phase of pregnancy (7-13 weeks) and 77.9% in late phase (34-36 weeks). The majority of them were below 35 years and non-smokers without gestational diabetes. Notably, 30.9% of subjects presented with Moderate/Severe periodontitis (CDC/AAP), and 35.8% with Stages II-IV periodontitis (AAP/EFP). Referring to the CDC/AAP definition, the AUC, Youden's index, and κ of the AAP/EFP classification were 0.979, 0.890, and 92.9%, respectively. The modified FDI-CG system improved the AUC (0.815), Youden's index (63.0%), and κ (0.544) with reference to the original one. CONCLUSIONS: This study shows that the AAP/EFP classification is in high agreement with the CDC/AAP definition among the pregnant women. The phases of pregnancy-integrated FDI scoring system may serve as a convenient screening tool for maternal periodontal diseases in general dental practice.

Periodontitis links to concurrent metabolic disorders and abnormal liver function in pregnant women.

OBJECTIVE: This cross-sectional study investigated the association of periodontitis with the metabolic status and hepatic function in pregnant women. MATERIALS AND METHODS: Full-mouth periodontal conditions, metabolic profiles, and hepatic function were assessed in 219 self-reported healthy pregnant females. The association of periodontal status with the systemic parameters was evaluated by parametric and non-parametric tests, and multivariate logistic regression analysis. RESULTS: Overall, periodontal status was positively associated with the metabolic profiles and hepatic function test results. The subjects with periodontitis exhibited higher levels of body mass index (BMI) (p < 0.01) and serum aspartate transaminase (AST) (p < 0.05), elevated diastolic blood pressure (DBP) (p < 0.05), and lower levels of high-density lipoprotein cholesterol (p < 0.05) than those of the counterparts. The periodontitis severity was strongly correlated with BMI and AST levels, and the extent of periodontal inflammation was related to DBP (p < 0.01). The periodontitis patients at 34-36 gestational weeks showed higher blood pressure and AST levels than those of non-periodontitis subjects (p < 0.05). CONCLUSION: Our findings on the notable links of periodontitis to concurrent metabolic disorders and abnormal liver function in pregnant women highlight the need of proactive integration of regular periodontal screening and healthcare in maternal programs for promoting optimal health and wellbeing of mothers-to-be and newborns.

Single and combined effects of microplastics and lead on the freshwater algae Microcystis aeruginosa.

Recently, the pollution of microplastics (MPs) in the global freshwater environment has become increasingly problematic, but there are few studies on the freshwater environment risks of MPs. The present study, therefore, has investigated the single and combined effects of MPs and lead (Pb) on the freshwater algal Microcystis aeruginosa. Results showed that Pb-only (>0.05 mg·L-1) promoted the growth of algal cells, while MPs-only (1 mg L-1) resulted in growth inhibition. However, compared with the corresponding concentration of Pb-only groups, the growth of algal cells was promoted in MPs + Pb treatments. MPs-only and Pb-only (0.5 mg L-1) both reduced the content of photosynthetic pigments and affected algal photosynthesis. The MPs-only treatment and MPs + Pb2+ (no pretreatment, 0.5 mg L-1 Pb2+) treatments showed significant cell aggregation. At the same time, MPs-only caused a significant increase in bound extracellular polysaccharides (bEPS), while 0.5 mg L-1 Pb reduced bEPS. Furthermore, under high Pb stress (0.5 mg L-1), the effects of combined MPs and Pb on chlorophyll content, antioxidant enzyme activity (peroxidase (POD), catalase (CAT)), and damage to algal cells were less compared to individual effects, and the combination of MPs and Pb had a synergistic effect on promoting aggregations of M. aeruginosa. These results demonstrate that single and combined effects of MPs and Pb can induce differential responses in the freshwater algal M. aeruginosa, which can have a significant impact on aquatic ecosystems.

Proposal and In-Depth Analysis of Emergency Treatment Procedures for Removing Fractured Abutments in Implants With Tapped-In Connections: Case Report.

In implant-supported prostheses, the most frequently reported mechanical complications after implant restoration are loosening or fracture of abutments or screws. Such complications have serious consequences, and removal of fractured abutments or screws is difficult. There are various methods to remove fractured abutment screws in implants with screwed-in connections. However, no approach has been reported to retrieve solid abutments in implants with a locking-taper implant-abutment connection, which are rarely observed in clinical settings. This study presents the case of a 62-year-old male patient with a fractured abutment in an upper-right second premolar implant. Abutment fracture is a common mechanical complication after dental implantation. Parafunctional habits and occlusal overloading may generate excessive occlusal forces, which increase the risk of mechanical complications. This report presents a series of emergency procedures for removing a fractured solid abutment and fabricating a new prosthesis to restore the edentulous area. In this retrospective analysis, the authors deeply consider the whole treatment, through which the deficiencies of the treatment are noted, and corresponding future directions are discussed. This case report presents a convenient approach to removing a solid abutment in a sudden emergency, discusses possible reasons for solid abutment fractures, designs a new rescue kit for easy retrieval of such abutments and summarizes a valid solution for removing fractured solid abutments.

Non-thermal plasma reduces periodontitis-induced alveolar bone loss in rats.

Periodontitis, a chronic infectious disease induced by microbial biofilm, is one of the most common diseases worldwide. Scaling and root planning (SRP) has always been recognized as the typical treatment. However, the therapeutic efficiency is often limited due to the intraoperative bleeding and the limitations of instruments. Non-thermal atmospheric plasma (NTP) appears to be a potential tool for periodontitis due to its promising biofilm degradation and decontamination effects. In this study, we investigated the role of NTP, as an adjuvant approach for the treatment of ligature-induced periodontitis in rats. Herein we showed that SRP or SRP-NTP application attenuated the periodontitis-induced alveolar bone loss, reflected by the increased BV/TV value and the decreased CEJ-AB distance, which might be related to the lower detection rate of periodontal pathogen in SRP and SRP-NTP groups. Besides, SRP-NTP rats showed less bone loss and lower CEJ-AB distance than that of SRP group at 30d post treatment, indicating a more comprehensive and long-lasting effect of SRP-NTP. A remarkable decrease of osteoclast number and lower expression of RANKL was also detected in SRP-NTP rats. In addition, expression of inflammatory-related cytokines such as TNF-α and IL-1ß decreased significantly in SRP-NTP group, while IL-10 level increased substantially. These results together illustrated that a combination of SRP and NTP treatment was an effective way to prevent periodontitis progress, which reduced alveolar bone loss and promoted periodontium restoration in ligature-induced periodontitis rats. In conclusion, non-thermal plasma treatment may be considered as a feasible and effective supplementary approach to control periodontitis.

Picometer-resolution dual-comb spectroscopy with a free-running fiber laser.

Dual-comb spectroscopy holds the promise as real-time, high-resolution spectroscopy tools. However, in its conventional schemes, the stringent requirement on the coherence between two lasers requires sophisticated control systems. By replacing control electronics with an all-optical dual-comb lasing scheme, a simplified dual-comb spectroscopy scheme is demonstrated using one dual-wavelength, passively mode-locked fiber laser. Pulses with a intracavity-dispersion-determined repetition-frequency difference are shown to have good mutual coherence and stability. Capability to resolve the comb teeth and a picometer-wide optical spectral resolution are demonstrated using a simple data acquisition system. Energy-efficient, free-running fiber lasers with a small comb-tooth-spacing could enable low-cost dual-comb systems.

Advances in osteoimmunomodulation of biomaterials after intrabone implantation: focus on surface hydrophilicity.

Biomaterials intended for intrabone implantation are extensively utilized in orthopedic and dental applications. Their surface properties, particularly hydrophilicity, significantly influence the biological interactions surrounding the implant, ultimately determining the implant's in vivo fate. Recently, the role of osteoimmunomodulation in these implantable biomaterials has been recognized for its importance in regulating biomaterial-mediated osteogenesis. Consequently, it is imperative to elucidate the correlation between hydrophilicity and the immune response for the development of osteoimmunomodulatory implants. Herein, this review highlights recent advances in osteoimmunomodulation of biomaterials after intrabone implantation from a novel perspective-surface hydrophilicity, and summarizes the series of immune reactions and subsequent bone remodeling that occur in response to hydrophilic implants, focusing on protein adsorption, the behaviors of major immune cells, and osteoimmunomodulation-enhanced angiogenesis and osteogenesis. Hydrophilic biomaterials have the capacity to alter the surrounding immune microenvironment and accelerate the process of material-tissue bonding, thereby facilitating the successful integration of biomaterials with tissue. Collectively, the authors hope that this article provides strategies for modulating hydrophilicity to achieve osteoimmunomodulatory performance and further promotes the development of novel implantable biomaterials for orthopedic and dental applications.

Novel Nonthermal Atmospheric Plasma Irradiation of Titanium Implants Promotes Osteogenic Effect in Osteoporotic Conditions.

Osteoporosis is a metabolic disease characterized by bone density and trabecular bone loss. Bone loss may affect dental implant osseointegration in patients with osteoporosis. To promote implant osseointegration in osteoporotic patients, we further used a nonthermal atmospheric plasma (NTAP) treatment device previously developed by our research group. After the titanium implant (Ti) is placed into the device, the working gas flow and the electrode switches are turned on, and the treatment is completed in 30 s. Previous studies showed that this NTAP device can remove carbon contamination from the implant surface, increase the hydroxyl groups, and improve its wettability to promote osseointegration in normal conditions. In this study, we demonstrated the tremendous osteogenic enhancement effect of NTAP-Ti in osteoporotic conditions in rats for the first time. Compared to Ti, the proliferative potential of osteoporotic bone marrow mesenchymal stem cells on NTAP-Ti increased by 180% at 1 day (P = 0.004), while their osteogenic differentiation increased by 149% at 14 days (P < 0.001). In addition, the results indicated that NTAP-Ti significantly improved osseointegration in osteoporotic rats in vivo. Compared to the Ti, the bone volume fraction (BV/TV) and trabecular number (Tb.N) values of NTAP-Ti in osteoporotic rats, respectively, increased by 18% (P < 0.001) and 25% (P = 0.007) at 6 weeks and the trabecular separation (Tb.Sp) value decreased by 26% (P = 0.02) at 6 weeks. In conclusion, this study proved a novel NTAP irradiation titanium implant that can significantly promote osseointegration in osteoporotic conditions.

Clinical phenotype and genetic function analysis of a family with hypomyelinating leukodystrophy-7 caused by POLR3A mutation.

Hypomyelinating leukodystrophy (HLD) is a rare genetic heterogeneous disease that can affect myelin development in the central nervous system. This study aims to analyze the clinical phenotype and genetic function of a family with HLD-7 caused by POLR3A mutation. The proband (IV6) in this family mainly showed progressive cognitive decline, dentin dysplasia, and hypogonadotropic hypogonadism. Her three old brothers (IV1, IV2, and IV4) also had different degrees of ataxia, dystonia, or dysarthria besides the aforementioned manifestations. Their brain magnetic resonance imaging showed bilateral periventricular white matter atrophy, brain atrophy, and corpus callosum atrophy and thinning. The proband and her two living brothers (IV2 and IV4) were detected to carry a homozygous mutation of the POLR3A (NM_007055.4) gene c. 2300G > T (p.Cys767Phe), and her consanguineous married parents (III1 and III2) were p.Cys767Phe heterozygous carriers. In the constructed POLR3A wild-type and p.Cys767Phe mutant cells, it was seen that overexpression of wild-type POLR3A protein significantly enhanced Pol III transcription of 5S rRNA and tRNA Leu-CAA. However, although the mutant POLR3A protein overexpression was increased compared to the wild-type protein overexpression, it did not show the expected further enhancement of Pol III function. On the contrary, Pol III transcription function was frustrated (POLR3A, BC200, and tRNA Leu-CAA expression decreased), and MBP and 18S rRNA expressions were decreased. This study indicates that the POLR3A p.Cys767Phe variant caused increased expression of mutated POLR3A protein and abnormal expression of Pol III transcripts, and the mutant POLR3A protein function was abnormal.

Effects of microplastics/nanoplastics on Vallisneria natans roots and sediment: Size effect, enzymology, and microbial communities.

Microplastics/nanoplastics (MNPs) pollution in different environmental media and its adverse effects on organisms have received increasing attention from researchers. This paper compares the effects of natural concentrations of three different sizes (20 nm, 200 nm, and 2 µm) of MNPs on Vallisneria natans and sediments. MNPs with smaller sizes adhere more readily to V. natans roots, further promoting root elongation. In addition, the larger the particle size of MNPs, the higher the reactive oxygen species level in the roots, and the malondialdehyde level increased accordingly. In the sediment, 20 nm, and 200 nm MNPs increased the activity of related enzymes, including acid phosphatase, urease, and nitrate reductase. In addition, the dehydrogenase content in the treated sediments increased, and the content changes were positively correlated with the size of MNPs. Changes in microorganisms were only observed on the root surface. The addition of MNPs reduced the abundance of Proteobacteria and increased the abundance of Chloroflexi. In addition, at the class level of species composition on the root surface, the abundance of Gammaproteobacteria under the 20 nm, 200 nm, and 2 µm MNP treatments decreased by 21.19%, 16.14%, and 17.03%, respectively, compared with the control group, while the abundance of Anaerolineae increased by 44.63%, 26.31%, and 62.52%, respectively. These findings enhance the understanding of the size effects of MNPs on the roots of submerged plants and sediment.

3D printing tablets for high-precision dose titration of caffeine.

Through 3D printing (3DP), many parameters of solid oral dosage forms can be customised, allowing for truly personalised medicine in a way that traditional pharmaceutical manufacturing would struggle to achieve. One of the many options for customisation involves dose titration, allowing for gradual weaning of a medication at dose intervals smaller than what is available commercially. In this study we demonstrate the high accuracy and precision of 3DP dose titration of caffeine, selected due to its global prevalence as a behavioural drug and well-known titration-dependent adverse reactions in humans. This was achieved using a simple filament base of polyvinyl alcohol, glycerol, and starch, utilising hot melt extrusion coupled with fused deposition modelling 3DP. Tablets containing 25 mg, 50 mg, and 100 mg doses of caffeine were successfully printed with drug content in the accepted range prescribed for conventional tablets (90 - 110%), and excellent precision whereby the weights of all doses showed a relative standard deviation of no more than 3%. Importantly, these results proved 3D printed tablets to be far superior to splitting a commercially available caffeine tablet. Additional assessment of filament and tablet samples were reviewed by differential scanning calorimetry, thermogravimetric analysis, HPLC, and scanning electron microscopy, showing no evidence of degradation of caffeine or the raw materials, with smooth and consistent filament extrusion. Upon dissolution, all tablets achieved greater than 70% release between 50 and 60 min, showing a predictable rapid release profile regardless of dose. The outcomes of this study highlight the benefits that dose titration with 3DP can offer, especially to more commonly prescribed medications that can have even more harmful withdrawal-induced adverse reactions.

The Potential Value of Probiotics after Dental Implant Placement.

Dental implantation is currently the optimal solution for tooth loss. However, the health and stability of dental implants have emerged as global public health concerns. Dental implant placement, healing of the surgical site, osseointegration, stability of bone tissues, and prevention of peri-implant diseases are challenges faced in achieving the long-term health and stability of implants. These have been ongoing concerns in the field of oral implantation. Probiotics, as beneficial microorganisms, play a significant role in the body by inhibiting pathogens, promoting bone tissue homeostasis, and facilitating tissue regeneration, modulating immune-inflammatory levels. This review explores the potential of probiotics in addressing post-implantation challenges. We summarize the existing research regarding the importance of probiotics in managing dental implant health and advocate for further research into their potential applications.

Distribution and potential ecological risks of microplastics in Zhushan Bay, China.

The interaction between microplastics (MPs) and microorganisms may alter the distribution of antibiotic resistance genes (ARGs) in water and increase the ecological risk of drinking water sources. To investigate the characteristics of MPs geographical distribution and its potential ecological risk in typical urban water, this study was conducted in Zhushan Bay, and we carried out a combination of tests to analyze the distribution of MPs and the migration changes of their surface microbial community composition and ARGs in different media by 16S rRNA gene high-throughput sequencing, non-targeted metabolomics and qPCR genomics in the near-shore (I), middle area (Ⅱ) and near-lake (Ⅲ) of Zhushan Bay. The results showed that MPs in fibrous form were dominant in the aquatic environment of Zhushan Bay; Polyurethane (PU) and Silicone were the main MPs types in Zhushan Bay. The abundance of MPs in the water of Zhushan Bay was winter > summer > autumn > spring; and in the sediment was winter > summer > autumn > spring, respectively. The distribution results of MPs in geographical location are as follows: In the water I > â…¡ > â…¢, sediment exhibited Ⅱ > â…¢ > I. The results indicate that physicochemical factors will affect the geographical distribution of MPs and their surface microbial community composition in the aquatic environment of Zhushan Bay. More cooperative behaviors and increased metabolically important pathways occurred in the microbial network on water-MPs compared to sediment-MPs. However, the microbial community in the sediment-MPs was more stable and had higher abundance of mobile genetic elements (MGEs). A total of 362 differential metabolites were detected, of which 193 were up-regulated and 19 down-regulated differential metabolites. blaTEM, Sul, and inti1 were prevalent in both the water and sediments of Zhushan Bay. Sul1 was most contaminated in ARGs. This study provides the latest field data and insights into MPs pollution in key aquatic environments.

Fast, long-scan-range pump-probe measurement based on asynchronous sampling using a dual-wavelength mode-locked fiber laser.

A simple, fast and long-scan-range pump-probe scheme is experimentally demonstrated using a dual-wavelength passively mode-locked fiber laser. The pulse trains from the dual-wavelength laser have a small difference in their repetition frequencies inherently determined by the intracavity dispersion. This enables the realization of the asynchronous sampling scheme with a tens-of-nanosecond-long delay range and a picosecond scan step at a millisecond scan speed. Instead of two synchronized ultrafast lasers in the traditional asynchronous sampling scheme, just one fiber laser is needed in our scheme, which could significantly simplify the system setup.

Promoting the adhesion of human gingival epithelial cells on titanium surface by non-thermal atmospheric plasma irradiation.

OBJECTIVES: This work aimed to study the biological behavior of human gingival epithelial cells (HGECs) irradiated by non-thermal atmospheric plasma (NTAP) on a titanium surface. METHODS: Cultured HGECs (3⁃5 generations) with the best activity were digested and treated for varying times (0, 10, 20, 30, and 60 s) by NTAP and then seeded on the surface of a titanium disc. The HGECs were cultured in oral keratinocyte medium and 1% penicillin/streptomycin solution. The cells were kept in an atmosphere of 5% CO2 at 37 ℃ and incubated for different times (4, 12, 24, and 48 h; n=5). Cell counting kit-8 (CCK-8) was used to detect cell adhesion capacity. Scanning electron microscopy (SEM) was conducted to observe the morphology of cells on titanium plates. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to evaluate the gene expression of adhesion-related molecules, such as Laminin α3, Integrin ß4, and Plectin. RESULTS: The number of adhered cells increased at 0­20 s, whereas that gradually decreased at 20⁃60 s. Therefore, cell culture at the two time points showed that HGECs adhesion reached the maximum when NATP was irradiated for 20 s. Compared with the control group, more cells in the treatment group adhered to the titanium surface at each time point (P<0.05). Cells in the treatment group showed more irregular polygons, more protrusions and pseudopods, and a larger cell diffusion area on the titanium surface than those in the control group. qRT-PCR showed that the expression levels of Laminin α3, Integrin ß4, and Plectin adhesion-related genes on the titanium surface in the treatment group were higher than those in the control group at each culture time point (P<0.05). Western blot showed that the expression levels of Laminin α3, Integrin ß4, and Plectin adhesion-related proteins on the titanium surface were higher in the treatment group than in the control group at 4 and 12 h. CONCLUSIONS: After NTAP treatment, the results showed that 20 s of treatment time could maximize the number of adhered cells on the titanium surface; change the cell adhesion morphology; and significantly upregulate the expression of adhesion-related genes and proteins of Laminin α3, Integrin ß4, and Plectin. Furthermore, it could promote the biological sealing effect of HGECs on the titanium surface.

Single and combined toxicity effects of nanoplastics and bisphenol F on submerged the macrophyte Hydrilla verticillata.

Nano- and microplastics pose severe risks to the ecological environment. Nanoplastics (NPs) not only directly affect aquatic organisms, but also adsorb to other pollutants, resulting in compound pollution. Bisphenol F (BPF), an endocrine-disrupting chemical, is increasingly replacing bisphenol A (BPA) and is therefore widely distributed in the environment. In this study, the toxic effects of polystyrene nanoplastics (PS-NPs) and BPF and their combined exposure on the submerged macrophytes Hydrilla verticillata (H. verticillata) and leaf biofilms, were investigated. Results showed that 10 mg/L PS-NPs and combined exposure to 10 mg/L PS-NPs and 10 mg/L BPF significantly decreased the relative growth rate and chlorophyll content of H. verticillata, whereas BPF exposure alone had no impact on the growth and the contents of photosynthetic pigments in H. verticillata. Individual and combined exposure to PS-NPs and BPF can trigger antioxidant responses such as increased activities of superoxide dismutase, peroxidase, and malondialdehyde, as well as higher levels of glutathione S-transferase and glutathione and decreased catalase activity. The results of the scanning electron microscopy (SEM) showed that the nanoplastics particles were adsorbed on the surface of plant leaves, explaining their toxic effects, whereas BPF increases the sorption of PS-NPs on the surface of H. verticillata, potentially leading to PS-NPs enrichment in the food chain. The diversity and richness of the microbial community were altered by exposure to PS-NPs and BPF individually and in combination. The current study is the first to assess the effects of PS-NPs and BPF exposure on the growth, physiological characteristics, and leaf biofilm properties of submerged macrophytes.

Combined toxic effects of enrofloxacin and microplastics on submerged plants and epiphytic biofilms in high nitrogen and phosphorus waters.

With the wide application of plastic products, microplastic pollution has become a major environmental issue of global concern. Microplastics in aquatic environments can interact with organic pollutants, causing a combined effect on submerged macrophytes. This study investigated the response mechanisms of the submerged plant Myriophyllum verticillatum and epiphytic biofilm to the antibiotic enrofloxacin, microplastics, and their combined exposure in a high nitrogen and phosphorus environment. The results indicated that Myriophyllum verticillatum was not sensitive to enrofloxacin of 1 mg L-1, while 10 and 50 mg L-1 enrofloxacin inhibited the uptake of nitrogen and phosphorus by the plants, as well as triggered oxidative stress in the plant leaves, causing irreversible damage to the plant cells. In addition, enrofloxacin altered the structure of the leaf epiphytic biofilm community. Interestingly, 1, 5, and 20 mg L-1 microplastics had no significant effect on the plant, while they facilitated the aggregation of microorganisms, increasing the abundance of the leaf epiphyte biofilm. The combination of enrofloxacin and microplastics induced a synergistic effect on Myriophyllum verticillatum. Specifically, the rate of nitrogen and phosphorus uptake by the plant was reduced, the content of photosynthetic pigments decreased, and antioxidant enzyme activity was further increased. In addition, the diversity of the leaf epiphytic biofilm community was similar to the single enrofloxacin exposure. These results demonstrated the differences between single and combined exposures and provided a new theoretical basis to evaluate the harmful effects of enrofloxacin and microplastics on submerged macrophytes.

Comparison of early osseointegration of non-thermal atmospheric plasma-functionalized/ SLActive titanium implant surfaces in beagle dogs.

Background: Hydrophilic dental implants are gaining increasing interest for their ability to accelerate bone formation. However, commercially available hydrophilic implants, such as SLActive™, have some major limitations due to their time-dependent biological aging and lower cost-effectiveness. The non-thermal atmospheric plasma (NTAP) treatment is a reliable way to gain a hydrophilic surface and enhance osseointegration. However, a few studies have been carried out to compare the osseointegration of NTAP-functionalized titanium implants and commercially available hydrophilic implants. Purpose: In this study, we compare the osseointegration abilities of the NTAP-functionalized titanium implant and Straumann SLActive. Material and methods: The NTAP effectiveness was examined using in vitro cell experiments. Then, six beagle dogs were included in the in vivo experiment. Straumann SLActive implants, SLA implants, and SLA implants treated with NTAP were implanted in the mandibular premolar area of dogs. After 2 w, 4 w, and 8 w, the animals were sacrificed and specimens were collected. Radiographic and histological analyses were used to measure osseointegration. Results: NTAP treatment accelerated the initial attachment and differentiation of MC3T3-E1 cells. In the in vivo experiment, bone parameters (e.g., BIC value and BV/TV) and volume of new bone of NTAP groups were close to those of the SLActive group. Additionally, although there was no statistical difference, the osseointegration of SLActive and NTAP groups was evidently superior to that of the SLA group. Conclusion: NTAP-functionalized implants enhanced cell interaction with material and subsequent bone formation. The osseointegration of the NTAP-functionalized implant was comparable to that of the SLActive implant at the early osseointegration stage.