Neural crest cells emerge from the dorsal region of the fusing neural tube in vertebrate embryos, then migrate throughout tissues to differentiate into various cell types, including osteoblasts. In adults, subsets of neural crest-derived cells (NCDCs) reside as stem cells and are considered to be useful cell sources for regenerative medicine. Previous studies have suggested that these NCDC subsets persist into adulthood in mammals, especially those cells within the craniofacial compartments. Recently, our group found that NCDCs were scattered throughout tissues of the palate, gingiva, tongue, hair follicle, submandibular glands, and buccal mucosa of adult mice. NCDCs from the buccal mucosa can also form neurosphere-like structures that have the capability to differentiate into osteoblasts in the presence of bone morphogenetic protein-2. In addition, NCDCs in adults have characteristic gene expression profiles, especially their cell surface molecules. Thus, cell sorting using several specific cell surface molecules has been proposed as a useful method for isolating NCDCs with high purity. Together, these results suggest that NCDCs reside in various adult oral and maxillofacial regions, and possess the potential to differentiate into osteoblastic cells, indicating that these cells in adults may be a useful source for bone regeneration strategies. In this review, we discuss the distribution, isolation and osteoblastic differentiation potential of NCDCs isolated from various adult tissue sources in the oral and maxillofacial regions.

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Propofol is a short-acting intravenous anesthetic agent. Dexmedetomidine, a highly selective α₂-adrenergic receptor agonist, has a well-known sedative effect. Both agents exhibit cytoprotective effects in the nervous system under ischemic conditions. Recently, the combination of propofol plus dexmedetomidine was used for the sedation of mechanically ventilated patients in an intensive care unit, but there are few experimental reports of the protective effects of the propofol plus dexmedetomidine combination in cells. Meanwhile, intraoperative brain ischemia–reperfusion induces endoplasmic reticulum (ER) stress-mediated apoptosis. The aim of the present study was to clarify molecular details underlying the neuroprotection afforded by the combination of propofol plus dexmedetomidine against thapsigargin (TG)-induced ER stress in human neuroblastoma SH-SY5Y cells, and whether the combination provided more efficient neuroprotection. TG was used to generate ER stress in SH-SY5Y cells. Cells were pretreated with propofol or dexmedetomidine, individually or in combination, for 1 h before cotreatment with TG for 20 h. There was a significant increase in [Ca²⁺]_i, caspase activation, and the expression of ER stress biomarkers in TG-induced apoptotic cells. The increase in [Ca²⁺]_i and the induction of ER stress by TG were suppressed by pretreatment with propofol, dexmedetomidine, and their combination. The dexmedetomidine-induced reduction in caspase activity and ER stress biomarkers was inhibited by pretreatment with an α₂-adrenergic receptor antagonist, but was enhanced by pretreatment with a cAMP inhibitor. Treatment with the propofol plus dexmedetomidine combination exhibited the strongest protection against TG-induced apoptosis. These results demonstrate that the combination of propofol plus dexmedetomidine at clinically relevant concentrations suppresses ER stress-induced apoptosis in neuroblastoma SH-SY5Y cells. The findings suggest that the combination of propofol plus dexmedetomidine within a clinically relevant concentration range may be used safely in patients.

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The aim of the present study was to test the hypothesis that a novel serum Helicobacter Pylori IgG kit derived from Japanese H. pylori strains, namely the Sphere Light H. pylori IgG J kit (SL-HP J), would enable discrimination of H. pylori infection status. In total, 273 patients were enrolled in the study and underwent endoscopic examination at Inui Clinic of Internal Medicine. Serum H. pylori IgG titers were measured using the SL-HP J kit. Current H. pylori infection was defined as positivity in at least one H. pylori test (rapid urease test, urease breath test, monoclonal stool antigen test, or histology), excluding serology. Naïve H. pylori infection was defined as negativity in all H. pylori tests and chronic atrophic gastritis (CAG), as determined by endoscopy. Previous H. pylori infection was defined as negativity for all H. pylori tests despite the presence of CAG. After testing, 134 patients were deemed to be naïve to H. pylori infection, 83 patients were diagnosed with current H. pylori infection, and the remaining 56 patients were diagnosed with previous H. pylori infection. Median (±quartile deviation) titers in patients with naïve, previous, and current H. pylori infection were 0.8±0.4, 2.1±2.3, and 24.8±22.7U/ml, respectively. The receiver operating characteristic (ROC) curve for naïve and previous H. pylori infection to classify naïve H. pylori infection showed an area under the curve (AUC) of 0.910, with 83% sensitivity and 82% specificity for a cut-off level of ＜1.6U/ml; the ROC curve for previous and current H. pylori infection to classify current H. pylori infection had an AUC of 0.969, with 96% sensitivity and 88% specificity for a cut-off level of ≥3.3U/ml. The present study shows that serum H. pylori IgG titers may be used to determine H. pylori infection status.

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Autografts, which are commonly used for alveolar bone regeneration, often utilize the ilium and jaw bones as alternative bone graft materials. Maxillary and mandibular bones are developmentally derived from neural crest-derived cells (NCDCs), while the majority of trunk and limb bones are derived from mesoblast cells. Consequently, the host bone graft material might differ in developmental origin from the recipient bone. With such a potential mismatch in practical terms, it is unclear whether genuine jaw bone can be regenerated. We hypothesized that bones derived from NCDCs and mesoblast cells show different capacities for in vivo bone healing. To investigate this proposal, we undertook bone graft experiments using a murine model. We first perforated a 2-mm diameter area in both the frontal and parietal bones, which are derived from NCDCs and mesoblast cells, respectively; then we grafted various source materials into each bone defect. Mice were euthanized at 2 weeks after grafting, and histological analyses and immunohistochemistry were performed to evaluate differences in bone healing based on the various combinations of graft and recipient bones. The frontal bone was found to heal faster than the parietal bone. Parietal bone defects transplanted with maxillary and mandibular bone grafts exhibited closure, whereas iliac and femoral bone grafts did not result in full healing. Immunostaining for osteopontin also demonstrated good bone regeneration in the parietal bone defects using maxillary and mandibular bone graft materials. These results suggest that maxilla and mandible bones exhibit NCDC properties with an enhanced healing potential. We conclude that maxillary and mandibular bones are effective bone graft and graft bed materials.

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At present, there is no way to definitely know whether microscopic residual tumors (R1 disease) are present following pancreatectomy performed for the treatment of pancreatic ductal adenocarcinoma (PDAC). Therefore, we investigated whether the expression of the glucose transporter-1 protein (GLUT-1) could be used as a prognostic indicator for R1 PDAC. We retrospectively examined the association between overall survival (OS), clinicopathological factors, and GLUT-1 expression in 68 patients with resectable PDAC (total PDAC group) and in a subset of 28 patients with R1 disease (R1 PDAC group). The presence of R1 disease significantly influenced the OS rates of patients in the total PDAC group, but GLUT-1 expression did not. However, the median OS time was significantly shorter for GLUT-1-positive patients in the R1 PDAC group. GLUT-1 expression was found to be an independent predictor of decreased survival time (P=0.020). We propose that GLUT-1 expression testing will facilitate development of treatment plans for R1 PDAC patients.

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The aim of this study was to assess the performance of virtual non-calcium images from dual-energy computed tomography (DECT), using dual-source CT (DSCT). Forty-one patients suspected of having traumatic vertebral fractures who underwent DSCT with virtual non-calcium imaging were included in this study. For comparison, radiation exposure was measured in 11 patients receiving DSCT with a radiation exposure reduction system, and in 14 patients receiving conventional multi-detector-row CT scans. Radiation exposure, detectability of fractures and visual image quality were assessed and compared between the groups. Radiation exposure was less with the non-calcium image than with the other methods. The CT number (x-ray absorption coefficient of a pixel in a CT) for the affected vertebrae was significantly higher than for normal vertebrae. When the threshold of the CT number was determined as -25.6 HU, the sensitivity was 100% and specificity was 92.6%. In most cases, the quality of the virtual non-calcium image was inferior to the fat-suppressed T2-weighted magnetic resonance images. The virtual non-calcium image technique obtained using DSCT can be a useful part of the clinical diagnosis of vertebral fractures.

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Transforaminal lumbar interbody fusion (TLIF) for both anterior/posterior and superior/inferior decompression of foramina can be indicated. The purpose of this study was to examine the outcome of unilateral TLIF and pedicle screw (PS) fixation for lumbar foraminal stenosis. The subjects were 24 consecutive patients who underwent monosegmental fusion for lumbar foraminal stenosis; there were 14 men and 10 women. All subjects underwent fusion at L5-S for unilateral L5 radiculopathy. A titanium cage was used in 10 subjects (titanium group) and a carbon or polyetheretherketone (PEEK) cage was used in 14 subjects (carbon/PEEK group). Clinical conditions and radiological findings were examined pre- and postoperatively, and at the final follow-up. The mean Roland and Morris Disability index improved from 8.5 preoperatively to 3.8 points. Excellent and good patient satisfaction was obtained in 2/3 of the patients. The mean disc height was increased by 2.0mm immediately after surgery and by 1.1mm at the final follow-up compared with the height before surgery. Subsidence of the cage of more than 3.0mm was observed in 60% patients of the titanium group and in 14% patients of the carbon/PEEK group (P<0.05). Unilateral TLIF and PS fixation was demonstrated to be less invasive for paravertebral muscles with a lower incidence of adjacent lumbar foraminal stenosis, resulting in a good outcome. Although there was no significant difference in clinical outcomes, subsidence of the cage was 4-fold higher in the titanium cage group than in patients receiving the carbon/PEEK cages. These findings indicate that unilateral TLIF and PS fixation are useful procedures.

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Herein we report on the long-term survival of a surgical case of typical carcinoid tumor and supraclavicular lymph node metastasis at initial diagnosis. The present study is a follow-up to a previously published case report. Initially, a 73-year-old man was admitted to hospital for evaluation of an enlarged lymph node in his right supraclavicular fossa. Serum progastrin-releasing peptide (ProGRP) concentrations were markedly elevated, and carcinoid was diagnosed by histopathological examination of the excised supraclavicular lymph node. The patient underwent right upper lobectomy and mediastinal lymph node dissection via median sternotomy. The final diagnosis was Stage IIIB (pT1aN3M0) typical carcinoid. Serum ProGRP concentrations decreased to within the normal range, and follow-up computed tomography, performed approximately 10 years after surgery, showed no recurrence. For this patient, radical resection of metastatic lymph nodes was an effective treatment for his typical lung carcinoid.

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