Gastrin-releasing peptide expression and its effect on the calcification of developing mouse incisor.

Gastrin-releasing peptide (GRP) is considered to be one of the cancer growth factors. This peptide's receptor (GRPR) is known as a G protein-coupled receptor, regulating intracellular calcium storage and releasing signals. This study is the first to investigate the function of GRP during mouse incisor development. We hypothesized that GRP is one of the factors that affects the regulation of calcification during tooth development. To verify the expression pattern of GRP, in situ hybridization was processed during incisor development. GRP was expressed at the late bell stage and hard tissue formation stage in the epithelial tissue. To identify the genuine function of GRP during incisor development, a gain-of-function analysis was performed. After GRP overexpression in culture, the phenotype of ameloblasts, odontoblasts and predentin was altered compared to control group. Moreover, enamel and dentin thickness was increased after renal capsule transplantation of GRP-overexpressed incisors. With these results, we suggest that GRP plays a significant role in the formation of enamel and dentin by regulating ameloblasts and predentin formation, respectively. Thus, GRP signaling is strongly related to calcium acquisition and secretion during mouse incisor development.

Role of region-distinctive expression of Rac1 in regulating fibronectin arrangement during palatal shelf elevation.

Palatal shelf elevation is a crucial process in palate development, with the contribution of various factors. Disturbances in any factor during this process result in cleft palate. Prior to palatal shelf elevation starting from embryonic day 12.5, the Rac1 expression level in the bend region of the mid-palatal shelf progressively increases and the cell densities in the bend and groove regions gradually become higher than those in the middle region. The comparative decrease of cell density in the middle region is correlated with a gradual alteration of the arrangement of fibronectin (FN) fibers, whereas the bend and groove regions with higher cell densities maintain ring-like FN arrangements. Rac1 overexpression alters the fibrillar FN arrangement in the middle region to the ring-like arrangement by increasing cell density. This alteration is sufficient to induce the failure of palatal shelf elevation, ultimately leading to cleft palate. Furthermore, the inhibition of FN delays palatal shelf elevation. Thus, the spatiotemporal expression of Rac1 plays an impressive role in palatal shelf elevation by regulating FN arrangement within the palatal shelf.

Morphological and molecular changes associated with Pitchfork during mouse palate development.

Mammalian palate development is regulated by complex processes. Many cellular and molecular events, such as cell proliferation, apoptosis, cell migration and the epithelial mesenchymal transition, regulate proper palate development and some abnormalities in palate development lead to cleft palate. Various developmental disorders, such as cleft palate and disorders of the lung, kidney and heart, are known to be associated with ciliary defects. Pitchfork, a mouse embryonic node gene, is associated with ciliary targeting complexes located at the basal body during primary cilia disassembly. To determine the function of Pitchfork during palate development, we examine Pitchfork expression patterns and morphological changes in the developing secondary palate after Pitchfork over-expression. From embryonic day 12.5 (E12.5) to E13.5 in mice, Pitchfork was highly expressed in the developing mouse secondary palate. Morphological differences were observed in vitro in cultured palates in the Pitchfork over-expression group compared with the control group. Pitchfork over-expression induced primary cilia disassembly during palate development. Sonic hedgehog and Patched1 expression levels and palatine rugae morphology were altered in the over-expressed Pitchfork group during palate development. Thus, the proper expression levels of Pitchfork might play a pivotal role in normal secondary palate morphogenesis.

Analysis of Factors Related to Distal Proximal Caries on the Distal Surface of the Mandibular Second Molar Induced by an Impacted Mandibular Third Molar.

OBJECTIVE: To analyze the factors related to distal proximal caries of the mandibular second molar (MSM) induced by an impacted mandibular third molar (MTM). METHODS: A total 500 panoramic radiographs of patients with impacted MTMs who were treated in the Department of Stomatology of the Affiliated Hospital of Yanbian University between October 2017 and October 2019 were selected. Descriptive and bivariate analyses were conducted, and the diagnosis of caries in the MSM and the position of the MTM were evaluated. RESULTS: The posterior margin space of the MSM was larger in males (13.5 mm) than females (11.1 mm, P < 0.001) and correlated with the MTM's impacted depth and eruption degree (P < 0.001). The prevalence of distal proximal caries of the MSM was 37.6%, and a χ 2 test showed that age, impacted depth, impacted direction, impacted angle, degree of occurrence, and CEJ distance were correlated with caries in the distal adjacent surface of the MSM (P < 0.001). Logistic multivariate analysis showed that the impacted depth was at position A or B, the impacted direction was mesioangular, and the impacted angle was <80°. Distal adjacent caries of MSMs were prone to occur when entirely or partially emergent. CEJ distance was not an independent factor for caries. The severity of caries in an MSM's distal adjacent surface had statistical significance on the impacted depth and impacted angle (P < 0.001). CONCLUSION: The posterior margin space of the MSM influences the impacted condition of the MTM. Preventive extraction can be considered if the impacted angle is <80°, especially in the case of a fully or partially emergent MTM at position A or B and mesioangular impacted areas.

Apigenin Inhibits Proliferation, Migration, and Invasion of Human Tongue Carcinoma Tca8113 Cells Through Regulating the MAPK Signaling Pathways.

OBJECTIVE: This study aimed to examine the effects of apigenin (API) on the proliferation, migration, and invasion of human tongue squamous cell carcinoma Tca8113 cells and explore its probable mechanisms. METHODS: After treating Tca8113 cells with API, the cell proliferation, migration, and invasive capacities were identified by tetrazolium salt colorimetry (MTT) assay, cell scratch test, and Transwell chamber test. Cellular immunofluorescence staining was used to localize mitogen-activated protein kinase 1 (MAPK1) and extracellular regulated protein kinase (ERK) 1/2 proteins. Western blot was used to detect the variations of the related protein expression levels. RESULTS: 1)Through the MTT assay, API significantly inhibited cell proliferation (P<0.01). 2) In the cell scratch test, the distance of lateral migration after the API treatment was significantly shorter compared to the control group (P<0.01). 3) The invasion rate in the lower chamber of the Transwell chamber was lower in the API group (P<0.01). 4) Cellular immunofluorescence staining presented that the total-MEKK1 was localized in the cytoplasm, p-MEKK1 was localized in the nuclear membrane and cytoplasm, and p-ERK1/2 was localized in the cytoplasm and nucleus. ⑤ After API was applied to cells, the expressions of p-MEKK1 and p-ERK1/2 proteins significantly reduced (P<0.01). CONCLUSION: Apigenin (API) significantly inhibits the proliferation, migration, and invasion of Tca8113 cells and its mechanism may be associated with the MAPK signaling pathway.

TGF-ß downregulation overcomes gemcitabine resistance in oral squamous cell carcinoma.

OBJECTIVE: The aim of this study was to explore the mechanisms by which oral cancer acquires resistance to gemcitabine. METHODS: Oral squamous cell carcinoma (OSCC) cells were treated with gemcitabine upon infection or with a lentivirus harboring short hairpin RNA (shRNA) targeted to transforming growth factor-ß (TGF-ß). Then, Western blot, ELISA, migration assay, MTT assay, and animal experiments were used to explore the mechanism of resistance to gemcitabine treatment. RESULTS: After the treatment of non-transfected cells with gemcitabine, NF-κB and AKT activities were increased, which may have induced the OSCC resistance to gemcitabine. Then, we found that TGF-ß downregulation effectively reduced NF-κB and AKT phosphorylation levels after the administration of gemcitabine and increased the OSCC sensitivity to gemcitabine, resulting in cell death and the blunting of OSCC resistance to gemcitabine. The EMT was also reduced by TGF-ß downregulation combined with gemcitabine treatment. CONCLUSION: Cellular levels of TGF-ß constitute an important factor in gemcitabine resistance and TGF-ß silencing might represent a novel and potent strategy for overcoming OSCC resistance to gemcitabine.

The correlative hypotheses between Pitchfork and Kif3a in palate development.

It is well known that dysfunction of primary cilia during embryonic development causes a range of developmental disorders such as cleft lip and palate, lung, kidney and heart disease. Both Pitchfork and Kinesin family member 3a (Kif3a) are associating with primary cilia, but whether there is a correlation between them are still inconclusive. Our research confirmed that Pitchfork over-expression induced lateral cleft palate and primary cilia disassembly during palate development. We also demonstrated that Sonic hedgehog (Shh) and Patched1 (Ptc1) expression levels were altering in the over-expressed Pitchfork group during palate development. Then we observed by consulting a vast amount of literature that specific knockout of the Kif3a also induced lateral cleft palate and expended the expression domains of Shh and Gli1 during palate development. Furthermore, loss of the Kif3a results in disassembly of the primary cilia and eventually leads to abnormal palatal development. Finally, we found that both Pitchfork and Kif3a are accumulating at the basal body and ciliary necklace during the early phase of cilia assembly and disassembly and both of them are involved in ciliary transport. Based on the above evidence, we hypotheses that there may be a potential correlation between Pitchfork and Kif3a, that could regulate primary cilia disassembly during palate development.

Use of Gold Nanoparticle Fertilizer Enhances the Ginsenoside Contents and Anti-Inflammatory Effects of Red Ginseng.

Red ginseng, a steamed and sun-dried ginseng, is a popular health-promoting food in Korea and other Asian countries. We introduced nanofertilizer technology using gold nanoparticles in an effort to develop red ginseng with an elevated level of ginsenosides, the main active compounds of ginseng. Shoots of 6-year-old ginseng plants were fertilized three times with colloidal gold nanoparticle sprays. Red ginseng extract was prepared from the main roots. The concentrations of gold and ginsenosides were measured following gold nanoparticle treatment. To evaluate the anti-inflammatory effects, mouse peritoneal macrophages of male BALB/c mouse were stimulated with lipopolysaccharide plus interferon-γ in the presence of extracts from red ginseng with or without gold nanoparticle treatment. The content of ginsenosides, such as Rg1, Re, Rf, and Rb1, increased in ginseng treated with gold nanofertilizer whereas the steaming process increased only the levels of Rd and Rg3. The levels of nitric oxide, inducible nitric oxide synthase, and interleukin-6, but not tumor necrosis factor-α, were more suppressed in macrophages treated with extract from gold nanoparticle-treated red ginseng. Our results show that the use of a colloidal gold nanoparticle fertilizer improved the synthesis of ginsenosides in ginseng and enhanced the anti-inflammatory effects of red ginseng. Further research is required to elucidate the causal factors for the gold-induced change in ginsenoside synthesis and to determine the in vivo effect of gold nanoparticle-treated ginseng.

[Polymorphism of KIR gene family in Korean ethnic group of Jilin area].

OBJECTIVE: To analyze the polymorphism of natural killer cell immunoglobulin-like receptor (KIR)gene and the characteristics of its genotypes and haplotypes in Korean ethnic group of Jilin area, and to compare with that of Han nationality. METHODS: DNA samples randomly collected from 214 Han and 160 Korean populations were genotyped with PCR-SSP method, and KIR genotypes and haplotypes were assigned according to the standard model by Hsu et al. RESULTS: All individuals contain KIR 3DL3, KIR 2DL4, KIR 3DL2 with the genotype frequency of 100%; the most common genotypes were 2DL1, 2DL3, 3DL1, 3DP1(*)003 and 2DP1; the genotypes with low frequency were 2DL2, 2DS2, 2DS3, 3DP1(*)001/002/004. Thirty-nine different KIR genotype and 16 haplotypes had been found in Korean and Han individuals. The most common KIR genotypes were AJ and AF with frequency of 18.1%, 19.4% and 31.8%, 19.6%, respectively. The most common KIR haplotype was haplotype 2 with frequency of 41.8% (n = 127) and 51.2% (n = 216) (P < 0.05), respectively. CONCLUSION: KIR gene distribution in Jilin Korean ethnic group showed some common features of KIR gene polymorphisms in Chinese Han population, but also showed this nation's unique characteristics of KIR gene polymorphism.