Immediate curative effects of exercise therapy in patients with myalgia of the masticatory muscles.

BACKGROUND: Exercise therapy is occasionally considered as an initial treatment for temporomandibular disorders. However, pain can be exacerbated during exercise therapy. OBJECTIVE: To investigate the immediate curative effects of exercise therapy in patients with masticatory muscle myalgia. METHODS: Fifty-nine patients with masticatory muscle myalgia were included. Therapists performed exercise therapy (stretched the painful masseter and/or cervical muscles along the direction of muscle contraction) in 10 rounds of traction, each lasting 10 s. The patient's pain-free maximum mouth opening distance and degree of pain (VAS value) before and immediately after exercise therapy were compared using the Wilcoxon signed-rank test. The Mann-Whitney U test was used for the subgroup comparisons. RESULTS: Mouth opening increased from 41 (IQR 38-43) to 46 (IQR 43-48) mm and pain alleviation from 48 (IQR 31-56) to 21 (IQR 10-56) immediately following exercise therapy (p < .001 for both). None of the patients experienced pain exacerbation or reduction in mouth opening post-exercise. No difference in mouth opening distance changes according to sex, painful side, painful site and therapist were observed (p > .05 for all). Pain reduction was greater in patients with unilateral pain (26, IQR 12-39) than those with bilateral (13, IQR 5-25) (p = .019). There were no differences in the change in the degree of pain according to sex, painful site and therapist (p > .05 for all). CONCLUSION: Exercise therapy immediately enlarged the mouth opening distance and reduced myalgia; therefore, it could be helpful in managing masticatory muscle myalgia.

Dental pulp stem cell-derived small extracellular vesicle in irradiation-induced senescence.

Small extracellular vesicles (sEV) facilitate signaling molecule transfer among cells. We examined the therapeutic efficacy of human dental pulp stem cell-derived sEV (hDPSC-sEV) against cellular senescence in an irradiated-submandibular gland mouse model. Seven-week-old mice were exposed to 25 Gy radiation and randomly assigned to control, phosphate-buffered saline (PBS), or hDPSC-sEV groups. At 18 days post-irradiation, saliva production was measured; histological and reverse transcription-quantitative PCR analyses of the submandibular glands were performed. The salivary flow rate did not differ significantly between the PBS and hDPSC-sEV groups. AQP5-expressing acinar cell numbers and AQP5 expression levels in the submandibular glands were higher in the hDPSC-sEV group than in the other groups. Furthermore, compared with non-irradiated mice, mice in the 25 Gy + PBS group showed a high senescence-associated-ß-galactosidase-positive cell number and upregulated senescence-related gene (p16INK4a, p19Arf, p21) and senescence-associated secretory phenotypic factor (MMP3, IL-6, PAI-1, NF-κB, and TGF-ß) expression, all of which were downregulated in the hDPSC-sEV group. Superoxide dismutase levels were lower in the PBS group than in the hDPSC-sEV group. In summary, hDPSC-sEV reduced inflammatory cytokine and senescence-related gene expression and reversed oxidative stress in submandibular cells, thereby preventing irradiation-induced cellular senescence. Based on these results, we hope to contribute to the development of innovative treatment methods for salivary gland dysfunction that develops after radiotherapy for head and neck cancer.

Peripheral Nerve Regeneration in a Novel Rat Model of Dysphagia.

The superior laryngeal nerve (SLN) is known to play an essential role in the laryngeal reflex and swallowing. Damage to the SLN causes difficulty swallowing, that is, dysphagia. We successfully developed a novel rat model of dysphagia by SLN injury, in which we could evaluate the neuroregenerative capacity of stem cell from human exfoliated deciduous teeth (SHED). The dysphagic rats exhibit weight loss and altered drinking patterns. Furthermore, SLN injury induces a delayed onset of the swallowing reflex and accumulation of laryngeal debris in the pharynx. This rat model was used to evaluate the systemic application of SHED-conditioned medium (SHED-CM) as a therapeutic candidate for dysphagia. We found that SHED-CM promoted functional recovery and significant axonal regeneration in SLNs through the polarization shift of macrophages from activated inflammatory macrophages (M1) to anti-inflammatory macrophages (M2) and angiogenesis. This chapter describes the establishment of SLN-injury induced dysphagia rat model and the preparation and application of SHED-CM.

First molecular identification of Strongyloides vituli in cattle in Japan and insights into the evolutionary history of Strongyloides parasites of ruminants.

Traditionally, Strongyloides nematode infecting cattle had been thought to be a single species, S. papillosus. Surprisingly, Eberhardt et al. in 2008 reported two, rather than one Strongyloides species infected cattle, with one being S. papillosus and the other S. vituli. However, there was no subsequent report to support their findings. In July 2018, a case of a sudden death of a calf believed to be due to heavy infection with S. papillosus at a dairy farm in Miyazaki Prefecture, Japan, was reported. One month after the initiation of a deworming program to prevent further sudden deaths, fecal specimens from 24 cattle housed in the same barn were examined. Eight samples were positive for Strongyloides eggs. For species determination, the nucleotide sequences of 18S rDNA (small subunit ribosomal DNA gene), rpl-10 (ribosomal protein L10 gene), and mitochondrial (mt) cox1 (cytochrome c oxidase subunit 1 gene) were obtained. Typing data for all three marker genes indicated the presence of both species, S. papillosus and S. vituli, in the fecal samples. To our knowledge, this study is the first to support the original report by Eberhardt et al. regarding the sympatric existence of S. papillosus and S. vituli in cattle, and to report the presence of S. vituli in Japan. Interestingly, phylogenetic analyses of both rpl-10 and mt cox1 sequences indicated a closer genetic relationship of S. vituli with S. venezuelensis (Strongyloides of rats) than with S. papillosus, shedding light on the speciation history of Strongyloides nematodes.

RNA Sequencing-Based Bulked Segregant Analysis Facilitates Efficient D-genome Marker Development for a Specific Chromosomal Region of Synthetic Hexaploid Wheat.

Common wheat originated from interspecific hybridization between cultivated tetraploid wheat and its wild diploid relative Aegilops tauschii followed by amphidiploidization. This evolutionary process can be reproduced artificially, resulting in synthetic hexaploid wheat lines. Here we performed RNA sequencing (RNA-seq)-based bulked segregant analysis (BSA) using a bi-parental mapping population of two synthetic hexaploid wheat lines that shared identical A and B genomes but included with D-genomes of distinct origins. This analysis permitted identification of D-genome-specific polymorphisms around the Net2 gene, a causative locus to hybrid necrosis. The resulting single nucleotide polymorphisms (SNPs) were classified into homoeologous polymorphisms and D-genome allelic variations, based on the RNA-seq results of a parental tetraploid and two Ae. tauschii accessions. The difference in allele frequency at the D-genome-specific SNP sites between the contrasting bulks (ΔSNP-index) was higher on the target chromosome than on the other chromosomes. Several SNPs with the highest ΔSNP-indices were converted into molecular markers and assigned to the Net2 chromosomal region. These results indicated that RNA-seq-based BSA can be applied efficiently to a synthetic hexaploid wheat population to permit molecular marker development in a specific chromosomal region of the D genome.

Clinical Study of Bone Regeneration by Conditioned Medium From Mesenchymal Stem Cells After Maxillary Sinus Floor Elevation.

OBJECTIVE: This clinical study was undertaken to evaluate the safety of use of the secretome of bone marrow-derived mesenchymal stem cells (MSC-CM) for maxillary sinus floor elevation (SFE). MATERIALS AND METHODS: MSC-CM was prepared from conditioned medium from human bone marrow-derived MSCs. Six partially edentulous patients were enrolled in the study. MSC-CM was mixed with porous beta-tricalcium phosphate (ß-TCP) and implanted in 4 patients (experimental group), whereas only ß-TCP was implanted in the other 2 patients (control group). Six months after SFE, bone biopsies and histological assessments were performed. RESULTS: Bone formation was clinically confirmed in all cases. Although Hounsfield units in computed tomography images were not significantly different between the groups, histological analysis revealed a significant difference in newly formed bone area between the groups. In particular, bone volume in the center of the augmented area was significantly greater in the MSC-CM group. Newly formed bone consisted of lamellar bone in the MSC-CM group but woven bone in the ß-TCP group. CONCLUSION: The secretome of bone marrow-derived mesenchymal stem cells (MSC-CM) was used safely and has great osteogenic potential for regenerative medicine of bone.

Angiogenesis in newly regenerated bone by secretomes of human mesenchymal stem cells.

BACKGROUND: For an effective bone graft for reconstruction of the maxillofacial region, an adequate vascular network will be required to supply blood, osteoprogenitor cells, and growth factors. We previously reported that the secretomes of bone marrow-derived mesenchymal stem cells (MSC-CM) contain numerous growth factors such as insulin-like growth factor (IGF)-1, transforming growth factor (TGF)-ß1, and vascular endothelial growth factor (VEGF), which can affect the cellular characteristics and behavior of regenerating bone cells. We hypothesized that angiogenesis is an important step for bone regeneration, and VEGF is one of the crucial factors in MSC-CM that would enhance its osteogenic potential. In the present study, we focused on VEGF in MSC-CM and evaluated the angiogenic and osteogenic potentials of MSC-CM for bone regeneration. METHODS: Cytokines in MSC-CM were measured by enzyme-linked immunosorbent assay (ELISA). Human umbilical vein endothelial cells (HUVECs) were cultured with MSC-CM or MSC-CM with anti-VEGF antibody (MSC-CM + anti-VEGF) for neutralization, and tube formation was evaluated. For the evaluation of bone and blood vessel formation with micro-computed tomography (micro-CT) and for the histological and immunohistochemical analyses, a rat calvarial bone defect model was used. RESULTS: The concentrations of IGF-1, VEGF, and TGF-ß1 in MSC-CM were 1515.6 ± 211.8 pg/mL, 465.8 ± 108.8 pg/mL, and 339.8 ± 14.4 pg/mL, respectively. Tube formation of HUVECs, bone formation, and blood vessel formation were increased in the MSC-CM group but decreased in the MSC-CM + anti-VEGF group. Histological findings suggested that new bone formation in the entire defect was observed in the MSC-CM group although it was decreased in the MSC-CM + anti-VEGF group. Immunohistochemistry indicated that angiogenesis and migration of endogenous stem cells were much more abundant in the MSC-CM group than in the MSC-CM + anti-VEGF group. CONCLUSIONS: VEGF is considered a crucial factor in MSC-CM, and MSC-CM is proposed to be an adequate therapeutic agent for bone regeneration with angiogenesis.

Periodontal tissue regeneration using the cytokine cocktail mimicking secretomes in the conditioned media from human mesenchymal stem cells.

Secretomes in the conditioned media from human mesenchymal stem cells (MSC-CM) were previously demonstrated to promote periodontal tissue regeneration. By mixing insulin-like growth factor-1, vascular endothelial growth factor-A, and transforming growth factor-ß1 which were included in MSC-CM, we made the cytokine cocktail (CC) mimicking MSC-CM, and then evaluated its efficacy on periodontal tissue regeneration. In vitro, CC promoted the migration of dog bone marrow-derived stem cells and periodontal ligament cells, and the tube formation of human umbilical vein endothelial cells. In vivo, class II furcation defects were surgically created at premolars in dogs. After 4 weeks of vinylpolysiloxane-induced inflammation, defects were filled with or without CC mixed in hydroxypropyl cellulose, or enamel matrix derivative (EMD). After 8 weeks, periodontal tissues were evaluated histologically and immunohistochemically. CC showed promotional effects on angiogenesis and formation of new bone and cementum. Osteogenesis by CC was greater than that by EMD and cementogenesis by CC was as well as that by EMD. CC may be promising for periodontal tissue regeneration.

A defined mix of cytokines mimics conditioned medium from cultures of bone marrow-derived mesenchymal stem cells and elicits bone regeneration.

OBJECTIVES: We previously reported that conditioned medium from cultures of bone marrow-derived mesenchymal stem cells have strong potential to accelerate bone regeneration. We now examine in vitro and in vivo a defined cytokine cocktail that mimics the effects of conditioned medium on bone regeneration. MATERIALS AND METHODS: A cocktail of recombinant human insulin-like growth factor-1, vascular endothelial growth factor-A and transforming growth factor-ß1 was prepared at concentrations similar to those in conditioned medium. Conversely, these cytokines were depleted from conditioned medium, and the effects of the cocktail, the conditioned medium and the cytokine-depleted conditioned medium on bone regeneration were evaluated in vitro and in vivo. RESULTS: The cytokine cocktail and conditioned medium enhanced cell migration, tube formation, and expression of osteogenic and angiogenic genes. Depletion of cytokines significantly decreased the effects of conditioned medium in vitro. Similarly, the cytokine cocktail and conditioned medium, but not cytokine-depleted medium, increased bone regeneration in damaged rat calvarial bone. Immunohistochemistry indicated that the cytokine cocktail and conditioned medium strongly enhanced recruitment of endogenous stem cells and endothelial cells. CONCLUSIONS: The data indicate that the cytokine cocktail and conditioned medium enhance the migration of stem cells and endothelial cells to damaged bone, and elicit osteogenesis and angiogenesis.

Fine mapping of Hch1, the causal D-genome gene for hybrid chlorosis in interspecific crosses between tetraploid wheat and Aegilops tauschii.

Hybrid chlorosis, one of the reproductive barriers between tetraploid wheat and its D-genome progenitor, Aegilops tauschii, inhibits normal growth of synthetic wheat hexaploids. Hybrid chlorosis appears to be due to an epistatic interaction of two loci from the AB and D wheat genomes. Our previous study assigned the causal D-genome gene for hybrid chlorosis, Hch1, to the short arm of chromosome 7D. Here, we constructed a fine map of 7DS near Hch1 using 280 F2 individuals from a cross of two wheat synthetic lines, one showing normal growth and the other showing hybrid chlorosis. The hybrid chlorosis phenotype was controlled by a single dominant allele of the Hch1 locus in the synthetic hexaploids. Hch1 was closely linked to four new markers within 0.2 cM, and may be localized near or within the two Ae. tauschii scaffolds containing the linked markers on 7DS. Comparative analysis of the Hch1 chromosomal region for Ae. tauschii, barley and Brachypodium showed that a local inversion occurred in the region proximal to Hch1 during the divergence between barley and Ae. tauschii, and that the Hch1 region on wheat 7DS is syntenic to Brachypodium chromosome 1. These observations provide useful information for further studies toward map-based cloning of Hch1.

Peripheral Nerve Regeneration by Secretomes of Stem Cells from Human Exfoliated Deciduous Teeth.

Peripheral nerve regeneration across nerve gaps is often suboptimal, with poor functional recovery. Stem cell transplantation-based regenerative therapy is a promising approach for axon regeneration and functional recovery of peripheral nerve injury; however, the mechanisms remain controversial and unclear. Recent studies suggest that transplanted stem cells promote tissue regeneration through a paracrine mechanism. We investigated the effects of conditioned media derived from stem cells from human exfoliated deciduous teeth (SHED-CM) on peripheral nerve regeneration. In vitro, SHED-CM-treated Schwann cells exhibited significantly increased proliferation, migration, and the expression of neuron-, extracellular matrix (ECM)-, and angiogenesis-related genes. SHED-CM stimulated neuritogenesis of dorsal root ganglia and increased cell viability. Similarly, SHED-CM enhanced tube formation in an angiogenesis assay. In vivo, a 10-mm rat sciatic nerve gap model was bridged by silicon conduits containing SHED-CM or serum-free Dulbecco's modified Eagle's medium. Light and electron microscopy confirmed that the number of myelinated axons and axon-to-fiber ratio (G-ratio) were significantly higher in the SHED-CM group at 12 weeks after nerve transection surgery. The sciatic functional index (SFI) and gastrocnemius (target muscle) wet weight ratio demonstrated functional recovery. Increased compound muscle action potentials and increased SFI in the SHED-CM group suggested sciatic nerve reinnervation of the target muscle and improved functional recovery. We also observed reduced muscle atrophy in the SHED-CM group. Thus, SHEDs may secrete various trophic factors that enhance peripheral nerve regeneration through multiple mechanisms. SHED-CM may therefore provide a novel therapy that creates a more desirable extracellular microenvironment for peripheral nerve regeneration.

Continuous Moniezia benedeni infection in confined cattle possibly maintained by an intermediate host on the farm.

Infection with Moniezia benedeni is sometimes found in confined cattle in Japan. Between October 2011 and January 2013, we monitored the fecal egg prevalence at a confined cattle farm in Miyazaki prefecture where continuous M. benedeni infection has been recognized for years to evaluate the possible infection routes. Fecal egg prevalence changed seasonally with the highest in October 2011 (27.3%: 9/33). This was followed by a gradual decrease until July 2012 (9.4%: 3/32) and then an increase between August to December 2012 when new egg-excreting cases were observed. The pattern of seasonal changes was similar to that reported previously for cattle kept in a barn with an outside playing yard. Although M. benedeni-infected mites were not found, we constantly detected an oribatid mite, Oribatula sakamorii Aoki, 1970, in the litter of cattle bedding from May to October 2012. This species belongs to a genus which has been reported to be a suitable intermediate host for M. benedeni, suggesting that M. benedeni infection may have been autonomously maintained at the farm via oribatid mites living in the cowshed. When infected cattle were treated with praziquantel, it was found that a single oral inoculation with a dose of 5 mg/kg was effective for deworming.

Effects on transcription of mutations in ygjD, yeaZ, and yjeE genes, which are involved in a universal tRNA modification in Escherichia coli.

The Escherichia coli ygjD gene is critical for the universal tRNA modification N(6)-threonylcarbamoyladenosine, together with two other essential genes, yeaZ and yjeE. This study showed that the transcription of the thr and ilv operons in ygjD mutants was increased through the inhibition of transcription attenuation and that dnaG transcription was reduced.