Genetically engineered CXCR4-modified exosomes for delivery of miR-126 mimics to macrophages alleviate periodontitis.

Biofilm-related diseases are a group of diseases that tolerate antimicrobial chemotherapies and therefore are refractory to treatment. Periodontitis, a non-device chronic biofilm disease induced by dental plaque, can serve as an excellent in vivo model to study the important effects of host factors on the biofilm microenvironment. Macrophage activity is one of the key factors that modulate the progression of inflammation-driven destruction in periodontitis; therefore it is an important host immunomodulatory factor. In this study, the reduction of microRNA-126 (miR-126) with the recruitment of macrophages in periodontitis was confirmed in clinical samples, and a strategy for targeted delivery of miR-126 to macrophages was explored. Exosomes overexpressing the C-X-C motif chemokine receptor 4 (CXCR4) loaded with miR-126 (CXCR4-miR126-Exo) was successfully constructed, which reduced off-target delivery to macrophages and regulated macrophages toward the anti-inflammatory phenotype. In vivo local injection of CXCR4-miR126-Exo into sites of periodontitis in rats effectively reduced bone resorption and osteoclastogenesis and inhibited the progression of periodontitis. These results provide new insights for designing novel immunomodulatory factor targeted delivery systems to treat periodontitis and other biofilm-related diseases.

FGF8 and BMP2 mediated dynamic regulation of dental mesenchyme proliferation and differentiation via Lhx8/Suv39h1 complex.

The homeobox gene, LIM-homeobox 8 (Lhx8), has previously been identified as an essential transcription factor for dental mesenchymal development. However, how Lhx8 itself is regulated and regulates odontogenesis remains poorly understood. In this study, we employed an RNAscope assay to detect the co-expression pattern of Lhx8 and Suv39h1 in the dental mesenchyme, which coincided with the dynamic expression profiles of the early epithelium signal of Fibroblast Growth Factor 8 (FGF8) and the later mesenchymal signal Bone Morphogenetic Protein 2 (BMP2). Moreover, FGF8 activated Lhx8, whereas BMP2 repressed Lhx8 expression at the transcriptional level. The high expression of Lhx8 in the early dental mesenchyme maintained the cell fate in an undifferentiated status by interacting with Suv39h1, a histone-lysine N-methyltransferase constitutively expressed in the dental mesenchyme. Further in the ex vivo organ culture model, the knockdown of Suv39h1 significantly blocked the function of Lhx8 and FGF8. Mechanistically, Lhx8/Suv39h1 recognized the odontoblast differentiation-related genes and repressed gene expression via methylating H3K9 on their promoters. Taken together, our data here suggest that Lhx8/Suv39h1 complex is inversely regulated by epithelium-mesenchymal signals, balancing the differentiation and proliferation of dental mesenchyme via H3K9 methylation.

Structural insights into homotrimeric assembly of cellulose synthase CesA7 from Gossypium hirsutum.

Cellulose is one of the most abundant organic polymers in nature. It contains multiple ß-1,4-glucan chains synthesized by cellulose synthases (CesAs) on the plasma membrane of higher plants. CesA subunits assemble into a pseudo-sixfold symmetric cellulose synthase complex (CSC), known as a 'rosette complex'. The structure of CesA remains enigmatic. Here, we report the cryo-EM structure of the homotrimeric CesA7 from Gossypium hirsutum at 3.5-angstrom resolution. The GhCesA7 homotrimer shows a C3 symmetrical assembly. Each protomer contains seven transmembrane helices (TMs) which form a channel potentially facilitating the release of newly synthesized glucans. The cytoplasmic glycosyltransferase domain (GT domain) of GhCesA7 protrudes from the membrane, and its catalytic pocket is directed towards the TM pore. The homotrimer GhCesA7 is stabilized by the transmembrane helix 7 (TM7) and the plant-conserved region (PCR) domains. It represents the building block of CSCs and facilitates microfibril formation. This structure provides insight into how eukaryotic cellulose synthase assembles and provides a mechanistic basis for the improvement of cotton fibre quality in the future.

[Oral Health Management of Children during the Epidemic Period of Coronavirus Disease 2019].

Coronavirus disease 2019 (COVID-19) is becoming a major public health event affecting China and even the whole world. During the epidemic period of corona virus disease, appropriate oral health management and disease prevention of children is very important for children's oral and general health. In order to prevent the occurrence of cross-infection and epidemic spreading of COVID-19 during dental practice, the recommendations to parents include: not only training children to maintain hand hygiene at home, exercise appropriately, strengthen physical resistance, but also helping children develop good oral and diet habit such as effective brushing and flossing to avoid oral diseases and emergency. If non-emergency oral situation occur, parents could assist their child to take home based care such as rinsing to relieve the symptoms. When oral emergencies such as acute pulpitis, periapical periodontitis, dental trauma, oral and maxillofacial infections happen, parents and children should visit dental clinic in time with correct personal protection. During the epidemic period, children's oral emergencies should be treated in accordance with current guidelines and control of COVID-19.

[Screen and Function Study of the Key Regulative Odontogenic Genes in Mice].

OBJECTIVE: To screen the key odontogenic genes in mice and verify the odontogenic inducing effect on amniotic epithelial cells (WISH). METHODS: The spatially and temporally different expression of bone morphogenetic proteins 4 (BMP4), fibroblast growth factor 8 (FGF8), sonic hedgehog (SHH), lymphoid enhancer factor 1 (LEF1) proteins and their genes expression in the early odontogenesis stage (embryo day 10.5 (E10.5)、E11.5、E14.5) in fetal mice were detected by immunohistochemistry staining and quantitative real-time PCR (RT-qPCR). According to the results, we screened the probable key odontogenic genes. Then adding osteogenic inducing solution to induce non-odontogenic epithelium cells, WISH. After 3 weeks culture of non-odontogenic epithelial WISH for osteogenic induction, the epithelial-mesenchymal transformation cap ability was evaluated by using Alizarin (ALZ) red staining and RT-qPCR on the alkaline phosphatase ( ALP) mRNA expression level. Using germ layer recombination experiment to observe and verify whether the screened genes can induce non-odontogenic epithelium cells acquire odontogenesis ability. The recombined tissue grafts containing key genes were transplanted beneath the renal capsule of mice. RESULTS: The results of immunohistochemistry staining and RT-qPCR showed that on E10.5 BMP4 protein and gene were differently expressed in the first and second branchial arch epithelium, which synchronized the odontogenic capability transferring from epithelium to mesenchyme from E10.5-E14.5. Though the expression of FGF8 protein and gene existed such difference in the first and second branchial arch epithelium, there was no synchronization in transfer. The expression of LEF1 and SHH proteins and genes had neither difference nor synchronization. So far, we considered the BMP4 was the probable key odontogenic gene. Through 3 weeks' osteogenic induction, ALZ red stained positively and calcium nodules were observed in WISH, and the expression level of ALP mRNA increased. In the germ layer recombination experiment, exogenous BMP4 protein enabled the second branchial arch mesenchyme forming tooth-like structures after recombined with the second branchial arch epithelium or WISH. CONCLUSIONS: The proteins and genes of BMP4, FGF8, SHH and LEF1 are spatially and temporally differently expressed in the early tooth development stage in mice. The protein and gene of BMP4 are differently expressed between the first and second branchial arch epithelium and enables the non-odontogenic epithelium acquiring odontogenic ability. BMP4 is the possible key odontogenic gene.

Electron-acceptor loadings affect chloroform dechlorination in a hydrogen-based membrane biofilm reactor.

Chloroform (CF) can undergo reductive dechlorination to dichloromethane, chloromethane, and methane. However, competition for hydrogen (H2 ), the electron-donor substrate, may cause poor dechlorination when multiple electron acceptors are present. Common acceptors in anaerobic environments are nitrate (NO3- ), sulfate (SO42- ), and bicarbonate (HCO3- ). We evaluated CF dechlorination in the presence of HCO3- at 1.56 e- Eq/m2 -day, then NO3- at 0.04-0.15 e- Eq/m2 -day, and finally NO3- (0.04 e- Eq/m2 -day) along with SO42- at 0.33 e- Eq/m2 -day in an H2 -based membrane biofilm reactor (MBfR). When the biofilm was initiated with CF-dechlorination conditions (no NO3- or SO42- ), it yielded a CF flux of 0.14 e- Eq/m2 -day and acetate production via homoacetogenesis up to 0.26 e- eq/m2 -day. Subsequent addition of NO3- at 0.05 e- Eq/m2 -day maintained full CF dechlorination and homoacetogenesis, but NO3- input at 0.15 e- Eq/m2 -day caused CF to remain in the reactor's effluent and led to negligible acetate production. The addition of SO42- did not affect CF reduction, but SO42- reduction significantly altered the microbial community by introducing sulfate-reducing Desulfovibrio and more sulfur-oxidizing Arcobacter. Dechloromonas appeared to carry out CF dechlorination and denitrification, whereas Acetobacterium (homoacetogen) may have been involved with hydrolytic dechlorination. Modifications to the electron acceptors fed to the MBfR caused the microbial community to undergo changes in structure that reflected changes in the removal fluxes.

PLGA-based control release of Noggin blocks the premature fusion of cranial sutures caused by retinoic acid.

Craniosynostosis (CS), the premature and pathological fusion of cranial sutures, is a relatively common developmental disorder. Elucidation of the pathways involved and thus therapeutically targeting it would be promising for the prevention of CS. In the present study, we examined the role of BMP pathway in the all-trans retinoic acid (atRA)-induced CS model and tried to target the pathway in vivo via PLGA-based control release. As expected, the posterior frontal suture was found to fuse prematurely in the atRA subcutaneous injection mouse model. Further mechanism study revealed that atRA could repress the proliferation while promote the osteogenic differentiation of suture-derived mesenchymal cells (SMCs). Moreover, BMP signal pathway was found to be activated by atRA, as seen from increased expression of BMPR-2 and pSMAD1/5/9. Recombinant mouse Noggin blocked the atRA-induced enhancement of osteogenesis of SMCs in vitro. In vivo, PLGA microsphere encapsulated with Noggin significantly prevented the atRA-induced suture fusion. Collectively, these data support the hypothesis that BMP signaling is involved in retinoic acid-induced premature fusion of cranial sutures, while PLGA microsphere-based control release of Noggin emerges as a promising strategy for prevention of atRA-induced suture fusion.

Contribution of the mandible position to the facial profile perception of a female facial profile: An eye-tracking study.

INTRODUCTION: Studies concerning the visual attention of laypersons viewing the soft tissue facial profile of men and women with malocclusion are lacking. This study aimed to determine the visual attention to the facial profile of patients with different levels of mandibular protrusion and facial background attractiveness using an eye-tracking device. METHODS: The scanning paths of 54 Chinese laypersons (50% female, 50% male, aged 18-23 years) were recorded by an eye-tracking device when they observed composite female facial profile images (n = 24), which were combinations of different degrees of mandibular protrusion (normal, slight, moderate, and severe) and different levels of facial background attractiveness (attractive, average, and unattractive). Dependent variables (fixation duration and first fixation time) were analyzed using repeated-measures factorial analysis of variance. RESULTS: For normal mandibular profiles, the fixation duration of the eyes was significantly higher than that of other facial features (P <0.001). The lower face and nose received the least attention. As the degree of protrusion increased from slight to moderate, more attention was drawn to the lower face accompanied by less attention to eyes in the unattractive group (P <0.05). When protrusion degree increased from moderate to severe, attention shifted from nose to lower face significantly in the attractive group (P <0.05). Attention shift from eyes to lower face was also found in the average group when protrusion degree rose to moderate protrusion from normal profile (P <0.05). A significant interaction between facial attractiveness and mandibular protrusion was found in the lower face duration (P = 0.020). The threshold point (the point of mandibular protrusion degree that evoked attention to the lower face) of the attractive facial background was higher than that of the unattractive background. Once evoked, the effect of mandibular protrusion of the attractive group tended to be stronger than that of the unattractive group, though without statistical difference. CONCLUSIONS: Eyes are the most salient area. The increasing degree of mandibular protrusion tends to draw attention to the lower face from other facial features. Background attractiveness can modify this behavior.

Analysis of the influencing factors of PAEs volatilization from typical plastic products.

The primary emphasis of this research was to investigate the foundations of phthalate (PAEs) pollutant source researches and then firstly confirmed the concept of the coefficient of volatile strength, namely phthalate total content in per unit mass and unit surface area of pollutant sources. Through surveying and evaluating the coefficient of volatile strength of PAEs from typical plastic products, this research carried out reasonable classification of PAEs pollutant sources into three categories and then investigated the relationship amongst the coefficient of volatile strength as well as other environmental factors and the concentration level of total PAEs in indoor air measured in environment chambers. Research obtained phthalate concentration results under different temperature, humidity, the coefficient of volatile strength and the closed time through the chamber experiment. In addition, this study further explored the correlation and ratio of influencing factors that affect the concentration level of total PAEs in environment chambers, including environmental factors, the coefficient of volatile strengths of PAEs and contents of total PAEs in plastic products. The research created an improved database system of phthalate the coefficient of volatile strengths of each type of plastic goods, and tentatively revealed that the volatile patterns of PAEs from different typical plastic goods, finally confirmed that the coefficient of volatile strengths of PAEs is a major factor that affects the indoor air total PAEs concentration, which laid a solid foundation for further establishing the volatile equation of PAEs from plastic products.

Lhx6 and Lhx8: cell fate regulators and beyond.

As transcription factors of the lines (LIN)-11/Islet (Isl)-1/mitosis entry checkpoint (MEC)-3 (LIM)-homeobox subfamily, LIM homeobox (Lhx)6 and -8 are remarkably conserved and involved in the morphogenesis of multiple organ systems. Lhx6 and -8 play overlapping and distinctive roles, but in general act as cell fate mediators and in turn are regulated by several transcriptional factors, such as sonic hedgehog, fibroblast growth factors, and wingless-int (Wnt)/ß-catenin. In this review, we first summarize Lhx6 and -8 distributions in development and then explore how Lhx6 and -8 act as transcription factors and coregulators of cell lineage specification. Known Lhx6 and -8 functions and targets are outlined in neurogenesis, craniofacial development, and germ cell differentiation. The underlying mechanisms of Lhx6 and -8 in regulating cell fate remain elusive. Whether Lhx6 and -8 affect functions in tissues and organs other than neural, craniofacial, oocytes, and germ cells is largely unexplored. Taken together, Lhx6 and -8 are important regulators of cell lineage specification and may act as one of the pivotal mediators of stem cell fate. Undoubtedly, future investigations of Lhx6 and -8 biology will continue to yield fascinating insights into tissue development and homeostasis, in addition to their putative roles in tissue regeneration and ageing.

Objective method for evaluating orthodontic treatment from the lay perspective: An eye-tracking study.

INTRODUCTION: Currently, few methods are available to measure orthodontic treatment need and treatment outcome from the lay perspective. The objective of this study was to explore the function of an eye-tracking method to evaluate orthodontic treatment need and treatment outcome from the lay perspective as a novel and objective way when compared with traditional assessments. METHODS: The scanpaths of 88 laypersons observing the repose and smiling photographs of normal subjects and pretreatment and posttreatment malocclusion patients were recorded by an eye-tracking device. The total fixation time and the first fixation time on the areas of interest (eyes, nose, and mouth) for each group of faces were compared and analyzed using mixed-effects linear regression and a support vector machine. The aesthetic component of the Index of Orthodontic Treatment Need was used to categorize treatment need and outcome levels to determine the accuracy of the support vector machine in identifying these variables. RESULTS: Significant deviations in the scanpaths of laypersons viewing pretreatment smiling faces were noted, with less fixation time (P <0.05) and later attention capture (P <0.05) on the eyes, and more fixation time (P <0.05) and earlier attention capture (P <0.05) on the mouth than for the scanpaths of laypersons viewing normal smiling subjects. The same results were obtained when comparing posttreatment smiling patients, with less fixation time (P <0.05) and later attention capture on the eyes (P <0.05), and more fixation time (P <0.05) and earlier attention capture on the mouth (P <0.05). The pretreatment repose faces exhibited an earlier attention capture on the mouth than did the normal subjects (P <0.05) and posttreatment patients (P <0.05). Linear support vector machine classification showed accuracies of 97.2% and 93.4% in distinguishing pretreatment patients from normal subjects (treatment need), and pretreatment patients from posttreatment patients (treatment outcome), respectively. CONCLUSIONS: The eye-tracking device was able to objectively quantify the effect of malocclusion on facial perception and the impact of orthodontic treatment on malocclusion from the lay perspective. The support vector machine for classification of selected features achieved high accuracy of judging treatment need and treatment outcome. This approach may represent a new method for objectively evaluating orthodontic treatment need and treatment outcome from the perspective of laypersons.

Surface-chemistry effect on cellular response of luminescent plasmonic silver nanoparticles.

Cellular response of inorganic nanoparticles (NPs) is strongly dependent on their surface chemistry. By taking advantage of robust single-particle fluorescence and giant Raman enhancements of unique polycrystalline silver NPs (AgNPs), we quantitatively investigated effects of two well-known surface chemistries, passive PEGylation and active c-RGD peptide conjugation, on in vitro behaviors of AgNPs at high temporal and spatial resolution as well as chemical level using fluorescence and Raman microscopy. The results show that specific c-RGD peptide-αvß3 integrin interactions not only induced endosome formation more rapidly, enhanced constrained diffusion, but also minimized nonspecific chemical interactions between the NPs and intracellular biomolecules than passive PEGylation chemistry; as a result, surface enhanced Raman scattering (SERS) signals of c-RGD peptides were well resolved inside endosomes in the live cells, while Raman signals of PEGylated AgNPs remained unresolvable due to interference of surrounding biomolecules, opening up an opportunity to investigate specific ligand-receptor interactions in real time at the chemical level.

Influence of different polymers on crystallization tendency and dissolution behavior of cilnidipine in solid dispersions.

CONTEXT: Cilnidipine (CN) is a novel dihydropyridine calcium antagonist that is practically insoluble in aqueous media and exhibits a low oral bioavailability or limited clinical efficacy. OBJECTIVE: This study investigated the effects of three commercial and chemically diverse polymers - PVP, PVP/VA and Soluplus - on crystallization tendency and in vitro dissolution profiles of CN in order to determine an optimum carrier for composing the preferred solid dispersion (SD) of CN. METHODS: All these co-evaporated systems were characterized up to 3 months by thermoanalytical (DSC), crystallographic (POM, PXRD), microscopic (SEM) and spectroscopic (FTIR) techniques. RESULTS: The results showed that the polymers could be sorted by their effects of inhibiting CN crystallization in the ascending order: Soluplus, PVP/VA, PVP. The sequence was in accordance with that of the strength of drug-polymer hydrogen bonds revealed by FTIR spectra. It could be ascribed to relative hydrogen-bonding acceptor strengths of N-vinylpyrrolidone moiety in the polymer molecules. On the other hand, all the SDs showed enhanced dissolution profiles compared to pure CN alone. On their effects of enhancing CN dissolution, the polymers could be sorted in the descending order: Soluplus, PVP, PVP/VA. CONCLUSIONS: It implied that the dissolution behavior of CN could bear a close relationship to both hydration capacity and hydrogen-bonding interaction tendency of moieties of the polymers. It might suggest an optimal formulation for CN comprising both PVP and Soluplus.

[Comparison of the repair effects of Haiao oral biofilm alone or in combination with allogeneic bone graft in bone defects after jaw bone cyst surgery].

PURPOSE: To compare the repair effects of Haiao oral biofilm alone or in combination with allogeneic bone graft on bone defects after jaw bone cyst surgery. METHODS: A prospective study was conducted on 105 patients with bone defects after jaw bone cyst surgery who were admitted to Affiliated Hospital of Jiangnan University from November 2020 to July 2022. According to the random number table methods, the patients were divided into three groups: Haiao membrane group, allogeneic bone graft group and combination group. Among them, Haiao membrane group(35 patients) were repaired using Haiao oral biofilm; allogeneic bone group(35 patients) using allogeneic bone, while combined group (35 patients) using a combination of Haiao oral biofilm and allogeneic bone graft. The clinical basic data of three groups of patients were compared, including the healing effect at the incision, bone density at the bone defect, bone resorption and attachment loss. Statistical analysis was performed with SPSS 22.0 software package. RESULTS: There was no significant difference in general clinical data among the three groups (P＞0.05). The postoperative restoration effect of gingival soft tissue morphology in combined group was significantly better than that in Haiao membrane group and allogeneic bone graft group (P＜0.05). There was no significant difference in bone density at the bone defect site among the three groups before treatment(P＞0.05); 6 and 12 months after treatment, the bone density of the three groups was significantly improved (P＜0.05), and combined group was significantly higher than the other groups(P＜0.05). There was no significant difference in the vertical and lingual bone resorption levels among the three groups before treatment(P＞0.05); 6 and 12 months after treatment, the vertical and lingual bone resorption levels of the three groups were significantly reduced (P＜0.05), and combined group were significantly lower than the other groups (P＜0.05). There was no significant difference in attachment loss among the three groups before treatment(P＞0.05); 6 and 12 months after treatment, the attachment loss of the three groups decreased(P＜0.05), and combined group was significantly lower than the other groups(P＜0.05). CONCLUSIONS: The combination of Haiao oral biofilm and allogeneic bone graft has good repair effect in the treatment of bone defects after jaw bone cyst surgery, which is beneficial for the recovery of gingival soft tissue, improvement of bone density, reduction of bone resorption and attachment loss.

Diselenide-Containing Polymer Based on New Antitumor Mechanism as Efficient GSH Depletion Agent for Ferroptosis Therapy.

Glutathione (GSH) depletion-induced ferroptosis has emerged as a promising treatment for malignant cancer. It works by inactivating glutathione peroxidase 4 (GPX4) and facilitating lipid peroxidation. However, effectively delivering inducers and depleting intracellular GSH remains challenging due to the short half-lives and high hydrophobicity of small-molecule ferroptosis inducers. These inducers often require additional carriers. Herein, diselenide-containing polymers can consume GSH to induce ferroptosis for pancreatic cancer therapy. The diselenide bonds are controllably built into the backbone of the polycarbonate with a targeting peptide CRGD (Cys-Arg-Gly-Asp), which allows for self-assembly into stable nanoparticles (denoted CRNSe) for self-delivery. Significantly, at a concentration of 12 µg mL-1, CRNSe binds to the active site cysteine of GSH resulting in a thorough depletion of GSH. In contrast, the disulfide-containing analog only causes a slight decrease in GSH level. Moreover, the depletion of GSH inactivates GPX4, ultimately inducing ferroptosis due to the accumulation of lipid peroxide in BxPC-3 cells. Both in vitro and in vivo studies have demonstrated that CRNSe exhibits potent tumor suppressive ability with few side effects on normal tissue. This study validates the anti-tumor mechanism of diselenide-containing polymers in addition to apoptosis and also provides a new strategy for inherently inducing ferroptosis in cancer therapy.

Shape-Tunable Hollow Polysiloxane Nanoparticles Based on a Surfactant-Free Soft Templating Method and Their Application as a Drug Carrier.

A surfactant-free soft-templating method has been used to prepare polysiloxane hollow nanoparticles with a controllable shape. This method is simple and has the potential for large-scale preparation. For the first time, we successfully obtained hollow polysiloxane nanoparticles with different shapes, including eccentric hollow polysiloxane microspheres (EHPM), apple-like hollow polysiloxane microparticles (AHPM), and bowl-like hollow polysiloxane microparticles (BHPM), by simply changing the solvent. In this method, the hydrolyzed methyltriethoxysilane (MTES) not only stabilizes the system as a surfactant but also acts as a reactant for subsequent reactions, so no additional surfactant is needed. In addition, the formation mechanism of hollow polysiloxane microparticles with different shapes is also proposed: that is, MTES hydrolyzed under acidic conditions to form a surfactant, which changes the system from suspension to a stable oil-in-water emulsion. Then, under alkaline conditions, the hydrolyzed MTES polycondenses and nucleates at the oil-water interface. At the same time, with the process of polycondensation, the hydrolyzed MTES will migrate to the nucleation site driven by surface tension, thus forming an eccentric core/shell (solvent/polysiloxane) structure. Due to the different forces between hydrolyzed MTES and different solvents, the deviation degree of hollow in microspheres is different, thus forming particles with various morphologies. This synthesis method provides a new idea for the preparation of shapeable anisotropic hollow structures. Finally, we use AHPM to study the application of the drug load. The results show that the prepared hollow polysiloxane particles have a good drug loading capacity and release performance. It can be predicted that the shape-tunable hollow polysiloxane particles prepared by this method have broad application prospects in the field of drug delivery.

Accuracy of the Yakebot dental implant robotic system versus fully guided static computer-assisted implant surgery template in edentulous jaw implantation: A preliminary clinical study.

AIMS: To compare the accuracy of the Yakebot dental implant robotic system with that of fully guided static computer-assisted implant surgery (CAIS) template in edentulous implantation. MATERIALS AND METHODS: Thirteen patients with edentulous were recruited and divided into two groups: the Yake robotic system group (experimental) (n = 5) and the CAIS group (control) (n = 8). Postoperative cone-beam computed tomography (CBCT) was performed immediately, and the 3-dimensional positions of implants were obtained and compared with that in the preoperative design. The comparison showed platform, apical, depth, and angular deviations. A value of p < 0.05 was considered statistically significant. RESULTS: A total of 84 implants (36 in the robotic group and 48 in the CAIS group) were placed. The mean deviation at the implant platform, apex, depth, and angle in the CAIS group was 1.37 ± 0.72 mm, 1.28 ± 0.68 mm, 0.88 ± 0.47 mm, and 3.47 ± 2.02°, respectively. However, the mean deviation at the implant platform, apex, depth, and angle in the robotic group was 0.65 ± 0.25 mm, 0.65 ± 0.22 mm, 0.49 ± 0.24 mm, and 1.43 ± 1.18°, respectively. Significant differences in the four types of deviation (p < 0.05) between the two groups were observed. CONCLUSION: The accuracy of robotic system in edentulous implant placement was superior to that of the CAIS template, suggesting that robotic system is more accurate, safe, and flexible, can be considered a promising treatment in clinical practice.

Dialdehyde starch cross-linked aminated gelatin sponges with excellent hemostatic performance and biocompatibility.

Developing a hemostatic material suitable for rapid hemostasis remains a challenge. This study presents a novel aminated gelatin sponge cross-linked with dialdehyde starch, exhibiting excellent biocompatibility and hemostatic ability. This aminated gelatin sponge features hydrophilic surface and rich porous structure with a porosity of up to 80 %. The results show that the aminated gelatin sponges exhibit superior liquid absorption capacity and can absorb up to 30-50 times their own mass of simulated body fluid within 5 min. Compared with the commercial gelatin hemostatic sponge and non-aminated gelatin hemostatic sponge, the aminated gelatin hemostatic sponge can accelerate the hemostatic process through electrostatic interactions, demonstrating superior hemostatic performance in both in vitro and in vivo hemostasis tests. The aminated gelatin sponge can effectively control the hemostatic time within 80 s in the in vivo rat femoral artery injury model, significantly outperforming both commercial and non-aminated gelatin sponges. In addition, the aminated gelatin sponge also exhibits good biocompatibility and certain antibacterial properties. The proposed aminated gelatin sponge has very good application prospects for the management of massive hemorrhage.

Development of a tobramycin-loaded calcium alginate microsphere/chitosan composite sponge with antibacterial effects as a wound dressing.

Traditional dressings exhibit several disadvantages, as they frequently lead to bacterial infections, cause severe tissue adhesion and perform a relatively single function. Therefore, in this study, a composite sponge dressing with antibacterial properties and excellent physicochemical properties was developed. Six groups of tobramycin-loaded calcium alginate microspheres were prepared by changing the amount of tobramycin added, and the optimal group was selected. Then, seven groups of tobramycin-loaded calcium alginate microsphere/chitosan composite sponges were fabricated via a solvent blending process and a freeze-drying method. The surface morphology, physicochemical properties,in vitrodegradation properties,in vitrodrug release properties, antibacterial properties and cytotoxicity of the composite sponges were examined. Group 3.0 contained the best microspheres with the largest drug loading capacity, good swelling performance and cumulative drug release rate, obvious and sustained antibacterial activity, and good cytocompatibility. The tobramycin-loaded calcium alginate microsphere/chitosan composite sponges exhibited three-dimensional porous structures, and their porosity, swelling rate, water absorption and water retention rates and water vapor transmission rate met the standards needed for an ideal dressing. The comprehensive performance of the sponge was best when 20 mg of drug-loaded microspheres was added (i.e. group 20). The cumulative drug release rate of the sponge was 29.67 ± 4.14% at 7 d, the diameters of the inhibition zones against the three bacteria were greater than 15 mm, and L929 cell proliferation was promoted. These results demonstrated that the tobramycin-loaded calcium alginate microsphere/chitosan composite sponge with 20 mg of tobramycin-loaded microspheres shows promise as a dressing for infected wounds.

Elemental sulfur biorecovery from phosphogypsum using oxygen-membrane biofilm reactor: Bioreactor parameters optimization, metagenomic analysis and metabolic prediction of the biofilm activity.

This work investigated elemental sulfur (S0) biorecovery from Phosphogypsum (PG) using sulfur-oxidizing bacteria in an O2-based membrane biofilm reactor (MBfR). The system was first optimized using synthetic sulfide medium (SSM) as influent, then switched to biogenic sulfide medium (BSM) generated by biological reduction of PG alkaline leachate. The results using SSM had high sulfide-oxidation efficiency (98 %), sulfide to S0 conversion (∼90 %), and S0 production rate up to 2.7 g S0/(m2.d), when the O2/S ratio was ∼0.5 g O2/g S. With the BSM influent, the system maintained high sulfide-to-S0 conversion rate (97 %), and S0-production rate of 1.6 g S0/(m2.d). Metagenomic analysis revealed that Thauera was the dominant genus in SSM and BSM biofilms. Furthermore, influent composition affected the bacterial community structure and abundances of functional microbial sulfur genes, modifying the sulfur-transformation pathways in the biofilms. Overall, this work shows promise for O2-MBfR usage in S0 biorecovery from PG-leachate and other sulfidogenic effluents.