Premaxillary Repositioning in the Severe Form of Bilateral Cleft Lip and Palate.

Severe forms of bilateral cleft lip and palate remain a challenging issue. Although nasoalveolar molding dramatically improves overall treatment success, the position of the premaxilla often remains dislocated. The authors attempted to relocate the malpositioned premaxilla into the correct position to obtain the correct three-dimensional (3D) maxillary arch structure and growth. Eight patients with severe bilateral cleft lip and palate were treated with premaxillary osteotomy for premaxilla repositioning. The position of the premaxilla was measured directly using cephalometry. Two raters including orthodontists evaluated the 3D (anteroposterior, transverse, and sagittal) outcomes. Regarding the long-term effects of premaxillary repositioning on midfacial growth, 3D computed tomography scan data were used, including the measurement of the SNA, SNB, and ANB angles according to the time period (T0: preoperative; T1: immediate postoperative; T2: long-term postoperative). All bilateral cleft lips and palates were satisfactorily repaired without any complications, including any premaxillary vascular compromise, nonunion, and occlusal instability. The average visual analog scale scores (0-5) of the anteroposterior, vertical, and transverse dimensions were 3.9, 3.7, and 3.2, respectively. Regarding the effect of premaxillary repositioning on midfacial hypoplasia, the change in the ANB between T1 and T2 was not significant, implying that premaxillary repositioning did not affect the long-term harmony between the maxilla and mandible (ANB of T2-T1: P = 0.1016) based on interim growth data at the time of follow-up and study completion. Premaxillary repositioning effectively corrected the malpositioned premaxilla and repaired the accompanying wide alveolar cleft, achieving successful restoration of maxillary arch coordination. In addition, premaxillary osteotomy after 8 years of age does not seem to cause significant maxillary retrusion.

Recent advances and clinical translation of liposomal delivery systems in cancer therapy.

The limitations of conventional cancer treatment are driving the emergence and development of nanomedicines. Research in liposomal nanomedicine for cancer therapy is rapidly increasing, opening up new horizons for cancer treatment. Liposomal nanomedicine, which focuses on targeted drug delivery to improve the therapeutic effect of cancer while reducing damage to normal tissues and cells, has great potential in the field of cancer therapy. This review aims to clarify the advantages of liposomal delivery systems in cancer therapy. We describe the recent understanding of spatiotemporal fate of liposomes in the organism after different routes of drug administration. Meanwhile, various types of liposome-based drug delivery systems that exert their respective advantages in cancer therapy while reducing side effects were discussed. Moreover, the combination of liposomal agents with other therapies (such as photodynamic therapy and photothermal therapy) has demonstrated enhanced tumor-targeting efficiency and therapeutic efficacy. Finally, the opportunities and challenges faced by the field of liposome nanoformulations for entering the clinical treatment of cancer are highlighted.

An investigation of the microstructure and mechanical properties of dental zirconia manufactured by digital light processing 3D printing.

OBJECTIVES: This study was performed to investigate the microstructure and mechanical properties of dental zirconia manufactured by digital light processing (DLP) 3D printing and the clinical application prospects of this material. METHODS: The experiment (DLP) group was zirconia manufactured by DLP 3D printing, and the control (MILL) group was milled zirconia. The density, grain size, and phase composition were measured to study the microstructure. Flexural strength was measured by using three-point bending tests, while Vickers hardness was determined through a Vickers hardness tester. Fracture toughness was tested using the single-edge V-notched beam method. RESULTS: Zirconia density of the DLP group was (6.019 8±0.021 3) g·cm-3, and the average grain size was (0.603 0±0.032 6) µm, but without statistical difference with the corresponding values of the MILL group (P>0.05). Tetragonal phase was found in the X-ray diffraction patterns of the DLP and MILL groups. The flexural strength of the DLP group was (1 012.7±125.5) MPa, and Vickers hardness was (1 238.5±10.8) HV1, which was slightly lower than that of the MILL group (P<0.05). The fracture toughness of the DLP group was (7.22±0.81) MPa·m1/2, which was not statistically different from that of the MILL group (P>0.05). CONCLUSIONS: Zirconia manufactured by DLP 3D printing had microstructure and mechanical properties similar to those of the milled zirconia. Only the flexural strength and the Vickers hardness of the experimental zirconia were slightly lower than those of the milled zirconia. Therefore, DLP-manufactured zirconia has a promising future for clinical use.

[Research progress in the relationship between Veillonella and oral diseases].

Veillonella species, known as the early colonizer of oral biofilm, are prevalent in oral microbiota. Seven Veillonella species have been isolated from oral cavity. Their distribution varies not only with different people but also with different sites in the oral cavity. Oral Veillonella are associated with oral diseases. They contribute to the adhesion of Streptococcus mutans and consume the lactate generated by streptococci. Veillonella species play an important role in the occurrence and development of periodontal diseases by providing adhesion sites for Porphyromonas gingivalis and boosting immune responses. The production of lipopolysaccharide and H2S is related to other oral diseases, such as pulpitis, periapical periodontitis, and halitosis. Several studies have been conducted on the relationship between Veillonella and oral diseases and the interaction between Veillonella and other pathological microorganisms, but limited knowledge is available at the molecular level. This article reviews the research progress in the relationship between Veillonella and oral infectious diseases, such as dental caries and periodontal diseases.

Human lung epithelial cells A549 epithelial-mesenchymal transition induced by PVA/Collagen nanofiber.

Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells lose their cell-cell contact to become mesenchymal stem cells, which is important on development and embryogenesis, wound healing, and cancer metastasis. This research aims to investigate the effect of topological cue as modulating factor on the EMT by tuning the diameter of electrospinning nanofiber. The cell-nanofiber interaction between human lung epithelial cell A549 and electrospinning nanofibers composed of polyvinyl alcohol (PVA) and type I collagen were investigated. The electrospinning of regenerated PVA/Collagen nanofibers were performed with water/acetic acid as a spinning solvent and glutaraldehyde as a chemical cross-linker. Parameterization on concentration, applied voltage and feeding rate was finalized to generate smooth nanofibers with good homogeneity. The scanning electron microscopy result demonstrated that A549 cell appropriately achieved extended morphology by the filopodia attaching to the surface of the nanofibrous mats. When the diameter changed from 90nm to 240nm, the A549 cell was correspondingly express varied EMT related genes. Gene expression analysis was conducted by qPCR using three typical markers for detecting EMT: N-cadherin (NCad), Vimentin (Vim), and Fibronectin (Fib). An increasing expression pattern was observed on cell culturing on 170nm sample with respect to cell cultured on 90nm and 240nm. This result indicated the 170nm PVA/Collagen nanofibers induce A549 cells to process epithelial-mesenchymal transition more seriously than those on 90nm or 240nm.

Different frequencies of Porphyromonas gingivalis infection in cancers of the upper digestive tract.

The high incidence rate of multiple carcinomas in the upper digestive tract is often explained in terms of involvement of the same underlying risk factors. It has been reported that the oral bacterium Streptococcus anginosus is associated with esophageal, gastric, and pharyngeal cancers. We previously reported occurrence of Porphyromonas gingivalis (P. gingivalis) DNA in esophagus cancer. In this study, the presence of P. gingivalis in specimens of various types of cancer from the upper digestive tract was investigated. Here we report that P. gingivalis was preferentially and frequently present in specimens of esophageal cancer as well as in those from dysplasia of the esophagus but rarely in matched noncancerous portions and are quite low or absent in cancers from the cardia or stomach. Therefore, it led us to propose that, the microorganism does not survive in conditions of high acidity. We then investigate the pH dependence of survival of P. gingivalis as well as the acid tolerance of it. We found that, exposure to acidic buffers of a wide range of pH values led to a decline in colony forming units of P. gingivalis, thus, providing a possible explanation for variations in frequencies of P. gingivalis infection in this study.

The pivotal role of fibrocytes and mast cells in mediating fibrotic reactions to biomaterials.

Almost all biomaterial implants are surrounded by a fibrotic capsule, although the mechanism of biomaterial-mediated fibrotic reactions is mostly unclear. To search for the types of cells responsible for triggering the tissue responses, we used poly-L glycolic acid polymers capable of releasing various reagents. We first identified that CD45(+)/Collagen 1(+) fibrocytes are recruited and resided within the fibrotic capsule at the implant interface. Interestingly, we found that the recruitment of fibrocytes and the extent of fibrotic tissue formation (collagen type I production) were substantially enhanced and reduced by the localized release of compound 48/80 and cromolyn, respectively. Since it is well established that compound 48/80 and cromolyn alter mast cell reactions, we hypothesized that mast cells are responsible for triggering fibrocyte recruitment and subsequent fibrotic capsule formation surrounding biomaterial implants. To directly test this hypothesis, similar studies were carried out using mast cell deficient mice, WBB6F1/J-Kit(W)/Kit(W-v)/, and their congenic controls. Indeed, mast cell deficient mice prompted substantially less fibrocyte and myofibroblast responses in comparison to C57 wild type mice controls. Most interestingly, subcutaneous mast cell reconstitution of WBB6F1/J-Kit(W)/Kit(W-v)/J mice almost completely restored the fibrocyte response in comparison to the C57 wild type response. These results indicate that the initial biomaterial interaction resulting in the stimulation of mast cells and degranulation byproducts not only stimulates the inflammatory cascade but significantly alters the downstream fibrocyte response and degree of fibrosis.

Novel polymeric scaffolds using protein microbubbles as porogen and growth factor carriers.

Polymeric tissue engineering scaffolds prepared by conventional techniques like salt leaching and phase separation are greatly limited by their poor biomolecule-delivery abilities. Conventional methods of incorporation of various growth factors, proteins, and/or peptides on or in scaffold materials via different crosslinking and conjugation techniques are often tedious and may affect scaffold's physical, chemical, and mechanical properties. To overcome such deficiencies, a novel two-step porous scaffold fabrication procedure has been created in which bovine serum albumin microbubbles (henceforth MB) were used as porogen and growth factor carriers. Polymer solution mixed with MB was phase separated and then lyophilized to create porous scaffold. MB scaffold triggered substantially lesser inflammatory responses than salt-leached and conventional phase-separated scaffolds in vivo. Most importantly, the same technique was used to produce insulin-like growth factor-1 (IGF-1)-eluting porous scaffolds, simply by incorporating IGF-1-loaded MB (MB-IGF-1) with polymer solution before phase separation. In vitro such MB-IGF-1 scaffolds were able to promote cell growth to a much greater extent than scaffold soaked in IGF-1, confirming the bioactivity of the released IGF-1. Further, such MB-IGF-1 scaffolds elicited IGF-1-specific collagen production in the surrounding tissue in vivo. This novel growth factor-eluting scaffold fabrication procedure can be used to deliver a range of single or combination of bioactive biomolecules to substantially promote cell growth and function in degradable scaffold.