Maintenance of adult stem cells from human minor salivary glands via the Wnt signaling pathway.

BACKGROUND: Xerostomia is a salivary gland dysfunction that negatively impacts the life quality of patients; however, there is no effective treatment for xerostomia. Bioengineered organs, generated using stem cells obtained from newborn salivary glands and ligated injury models, are a new organ transplantation strategy that could be feasible for xerostomia treatment. Reconstruction of salivary gland organoids by seed cells obtained from human minor salivary glands will offer theoretical fundaments and technology support for clinical application and organ regeneration research. Herein, we aimed to propose a new method for culturing and enriching adult human minor salivary gland stem cells in vitro in a three-dimensional (3D) environment via Wnt signaling activation. METHODS: Obtained and characterized human minor salivary gland stem cells (hMSGSCs) with self-organization ability were 3D-cultured to generate organoids. We examined hMSGSCs proliferation and colony formation using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays. Telomerase reverse transcriptase staining, flow cytometry, immunofluorescence assay, RNA isolation, RT-PCR, and qPCR were performed to assess hMSGSCs structure and the function of reconstructive organoids in vitro. RESULTS: hMSGSCs showed typical epithelial-like characteristics, such as positive for CD49f and cell KRT expression. hMSGSCs served as adult stem cells in salivary glands and could differentiate into acinar and duct cells. Upon the addition of Noggin, CHIR99021, and Wnt3A to the 3D culture system, hMSGSCs showed higher LGR5 expression and decreased AMY1B and MUC5B expression. Therefore, the Wnt and bone morphogenetic protein (BMP) pathways are important in regulating hMSGSCs self-organization and differentiation. CONCLUSIONS: We showed that the stem cell properties of hMSGSCs in a 3D culture system can be maintained by activating the Wnt signaling pathway and inhibiting the BMP signaling pathway. Our findings contribute new insights on salivary gland organoid generation in vitro.

Using gelatin/curcumin nano-fiber membranes as scaffolds in a subcutaneous model for tissue engineered cartilages.

Engineered cartilage has several applications in treating cartilage ossification, however, its use is restricted clinically. We explored the feasibility of engineered cartilage in constructing tissues using gelatin/curcumin nano-fiber membranes as scaffolds in subcutaneous models. We constructed cartilage with gelatin nano-fiber membrane (control group) and gelatin/curcumin nano-fiber membrane (experimental group) as scaffolds. After the material was implanted into the back of BALB/c mice, gross view observation was performed. Histological examination was performed 3 and 12 weeks after implantation in vivo, and cartilage formation at different time points was compared. Gross observation showed that compared to the control group, the vascularization of nearby tissues in the experimental group was significantly inhibited. The Scanning electron microscope observation showed that the chondrocytes in both groups adhered well. The growth curve of the chondrocytes showed that curcumin had no significant effect on cell growth. Histological observation showed that the cell-material complexes in both groups had cartilage lacuna formation at 3 and 12 weeks. However, compared with that of the control group, the experimental group showed obvious absorption and thicker cartilage matrix with more homogenization. Gelatin/curcumin scaffolds were successfully used to construct engineered cartilage tissues in subcutaneous animal models. Our findings demonstrate that curcumin-loaded scaffolds have great clinical applications.

Postoperative Complications of Box-Shift Osteotomy for Orbital Hypertelorism.

OBJECTIVE: To summarize and analyze the postoperative complications of box-shift osteotomy performed at our center for Chinese orbital hypertelorism patients from 2008 to 2017. METHOD: This retrospective study reviews the records of 78 patients with complete medical records and at least 2 years of postoperative follow-up data. Both radiologic and anthropometric assessments were conducted before, 1 month after and 2 years after surgery to evaluate the bony and soft-tissue alterations. Postoperative complications were recorded during hospitalization and at each follow-up visit and divided into 3 groups: acute complications that occurred within 1 month after surgery; early complications that occurred within 6 months after surgery; and long-term complications that occurred within 2 years after surgery. RESULTS: Both bony and soft-tissue alterations were significant at 1 month after surgery. The acute complications that occurred in our center included infection (12.8%), cerebrospinal fluid leakage (29.5%), epilepsy (2.6%), and nasal tip skin necrosis (1.3%). The early complications included strabismus (11.5%) and nasolacrimal duct obstruction (3.8%). The long-term complications included insufficient correction (55.1%), palpable metal implants (92.3%) and a drooping nasal tip (33.9%). Due to the insufficient correction and the continued growth of rib graft, the difference in the hypertelorism index and nasal length, between one month and 2 years postoperatively were statistically significant (P < 0.01). Other radiographic and anthropometric measurements changed with growth without a significance difference between 1 month and 2 years after surgery. CONCLUSION: In this study, we recorded all postoperative complications of box-shift osteotomy. The challenge of our future work is to identify methods for decreasing the incidence of these complications.

Understanding the ontogeny and succession of Bacillus velezensis and B. subtilis subsp. subtilis by focusing on kimchi fermentation.

Bacillus subtilis and B. velezensis are frequently isolated from various niches, including fermented foods, water, and soil. Within the Bacillus subtilis group, B. velezensis and B. subtilis subsp. subtilis have received significant attention as biological resources for biotechnology-associated industries. Nevertheless, radical solutions are urgently needed to identify microbes during their ecological succession to accurately confirm their action at the species or subspecies level in diverse environments, such as fermented materials. Thus, in this study, previously published genome data of the B. subtilis group were compared to exploit species- or subspecies-specific genes for use as improved qPCR targets to detect B. velezensis and B. subtilis subsp. subtilis in kimchi samples. In silico analyses of the selected genes and designed primer sequences, in conjunction with SYBR Green real-time PCR, confirmed the robustness of this newly developed assay. Consequently, this study will allow for new insights into the ontogeny and succession of B. velezensis and B. subtilis subsp. subtilis in various niches. Interestingly, in white kimchi without red pepper powder, neither B. subtilis subsp. subtilis nor B. velezensis was detected.

Red pepper powder is a crucial factor that influences the ontogeny of Weissella cibaria during kimchi fermentation.

Weissella cibaria has been found in Korean kimchi and other sources, including fermented foods, Greek salami, Spanish sausages, and animal and human excrement. W. cibaria was recently reported to show anticancer, immunomodulatory, anti-inflammatory and antioxidant properties. Nevertheless, fundamental ecological succession studies are required to scientifically confirm the probiotic action of W. cibaria under various conditions, such as fermentation. Therefore, in the present study, we mined the W. cibaria KACC11862 genome in search of species-specific genes to use as new PCR targets for the detection and quantification of W. cibaria in kimchi. The sensitivity and specificity of the identified primer set from the putative outer membrane protein gene for the detection of W. cibaria KACC11862 in kimchi were analysed. Primer set specificity was evaluated using genomic DNA from eight W. cibaria isolates, 10 different species of Weissella and 13 other reference lactic acid bacteria (LAB) strains. Interestingly, by using the qPCR assay developed herein, we found that red pepper powder markedly affects the ontogeny of W. cibaria during kimchi fermentation.

The influence of red pepper powder on the density of Weissella koreensis during kimchi fermentation.

Weissella koreensis is a psychrophilic bacterium that is the dominant species found in kimchi and exhibits anti-obesity effects via its production of ornithine. In this study, we mined the genome of W. koreensis KACC15510 to identify species-specific genes that can serve as new targets for the detection and quantification of W. koreensis in kimchi. A specific polymerase chain reaction (PCR) primer set for the membrane protein-encoding gene of W. koreensis KACC15510 was designed and investigated to quantify its sensitivity and specificity for detecting the bacterium in kimchi. The specificity of the primer set was evaluated using genomic DNA from eight isolates of W. koreensis, 11 different species of Weissella and 13 other reference lactic acid bacterium (LAB) strains. In addition, red pepper powder was observed to strongly influence the density of W. koreensis during kimchi fermentation.