Secondary neurulation (SN) is a critical process to form the neural tube in the posterior region of the body including the tail. SN is distinct from the anteriorly occurring primary neurulation (PN); whereas the PN proceeds by folding an epithelial neural plate, SN precursors arise from a specified epiblast by epithelial-to-mesenchymal transition (EMT), and undergo self-renewal in the tail bud. They finally differentiate into the neural tube through mesenchymal-to-epithelial transition (MET). We here overview recent progresses in the studies of SN with a particular focus on the regulation of cell lineage, self-renewal, and EMT/MET. Cellular mechanisms underlying SN help to understand the functional diversity of the tail in vertebrates.

Secondary neurulation (SN) is a critical process to form the neural tube in the posterior region of the body including the tail. SN is distinct from the anteriorly occurring primary neurulation (PN); whereas the PN proceeds by folding an epithelial neural plate, SN precursors arise from a specified epiblast by epithelial-to-mesenchymal transition (EMT), and undergo self-renewal in the tail bud. They finally differentiate into the neural tube through mesenchymal-to-epithelial transition (MET). We here overview recent progresses in the studies of SN with a particular focus on the regulation of cell lineage, self-renewal, and EMT/MET. Cellular mechanisms underlying SN help to understand the functional diversity of the tail in vertebrates.

Ciliary neurotrophic factor (CNTF) is one of the important factors in neuronal survival. Mutation in CNTF gene was found first in Japanese. We analyzed the CNTF genotype of 187 healthy volunteer of Korean, and compared the frequency difference in CNTF gene mutation among Korean, Japanese, and other nations or race. The number of normal homozygote was 138 (73.8%), mutant homozygote 47 (25.1%), and mutant homozygote was 2 (1.1%). The mutated allele frequency of CNTF gene in Korean was 13.6%, which was not significantly different from that of other nations or race (10~20%).
Asian Continental Ancestry Group ; Ciliary Neurotrophic Factor* ; Continental Population Groups ; Gene Frequency ; Genotype ; Healthy Volunteers ; Homozygote ; Humans ; Neurons

The teleost fish has been widely used in creating neurodegenerative models. Here we describe the teleost medaka fish Parkinson's disease (PD) models we developed using toxin treatment and genetic engineering. 1-Methyl-4-phenyl-1,2,3,4-tetrahydropyridine (MPTP), 6-hydroxydopamine (6-OHDA), proteasome inhibitors, lysosome inhibitors and tunicamycin treatment in our model fish replicated some salient features of PD: selective dopamine cell loss and reduced spontaneous movement with the last three toxins producing inclusion bodies ubiquitously in the brain. Despite the ubiquitous distribution of the inclusion bodies, the middle diencephalic dopaminergic neurons were particularly vulnerable to these toxins, supporting the idea that this dopamine cluster is similar to the human substantia nigra. PTEN-induced putative kinase 1 (PINK1) homozygous mutants also showed reduced spontaneous swimming movements. These data indicate that medaka fish can serve as a new model animal of PD. In this review we summarize our previous data and discuss future prospects.
Animals ; Brain ; Dopamine ; Dopaminergic Neurons ; Genetic Engineering ; Humans ; Inclusion Bodies ; Lysosomes ; Oryzias ; Oxidopamine ; Parkinson Disease ; Phosphotransferases ; Proteasome Inhibitors ; Protein Kinases ; Substantia Nigra ; Swimming ; Tunicamycin

PURPOSE: The aim of this study was to elucidate whether intrasynovial corticosteroid injections for trigger digit reduced the volume of the tendon and pulley on high-resolution ultrasonography. METHODS: Twenty-three digits of 20 patients with trigger digit were included. Each affected finger was graded clinically according to the following classification: grade I for pre-triggering, grade II for active triggering, grade III for passive triggering, and grade IV for presence of contracture. Axial ultrasound examinations were performed before an intrasynovial corticosteroid injection and at an average of 31 days after the injection. The transverse diameter, thickness, and cross-sectional area of the tendon and the thickness of the pulley were measured by two independent, blinded researchers. RESULTS: At least 1 grade of improvement was achieved in this study group by the time of the second examination. The transverse diameter and cross-sectional area of the tendon and the thickness of the pulley significantly decreased (P < 0.05). CONCLUSION: The injection of a single dose of betamethasone improved clinical symptoms by reducing the volume of both the tendon and pulley, which may be related to the fact that tendon and pulley ruptures are delayed by corticosteroid injections.
Adrenal Cortex Hormones ; Betamethasone* ; Classification ; Contracture ; Fingers ; Humans ; Rupture ; Tendons* ; Trigger Finger Disorder* ; Ultrasonography*

The aim of the present study was to clarify whether ATP binding cassette transporters are refractory factors in head and neck cancer chemotherapy. For in vitro and in vivo chemotherapeutic studies, we employed a human salivary gland adenocarcinoma cell line (HSY) and a human oral squamous cell carcinoma cell line (SCCSK) with vincristine (VCR) at clinically equivalent doses. Western blot analysis, reverse transcription-polymerase chain reaction, in vivo evaluation in xenograft models inoculated with cultured carcinoma cell line and drug efflux analysis were performed. VCR-treated SCCSK and HSY cells, as well as xenografted SCCSK and HSY cells in tumor-bearing nude mice, were found to express MDR1/ABCB1 and MRP1/ ABCC1. In addition to MDR1 and MRP1 mRNA, HSY/VCR and its cloned cells expressed MRP7/ABCC10 mRNA, but SCCSK/VCR did not express MRP7. Furthermore, drug resistance to VCR and docetaxel decreased in HSY/VCR in the presence of a competitive MRP7 inhibitor, 17-beta-estradiol-(17-beta-D-glucuronide). These results indicate that MDR1 and MRP1 expression are refractory factors in head and neck cancer chemotherapy and suggest that induction of MRP7 expression is involved in drug resistance in salivary gland adenocarcinomas.

PURPOSE: It has been suggested that resonance frequency analysis (RFA) can measure changes in the stability of dental implants during osseointegration. This retrospective study aimed to evaluate dental implant stability at the time of surgery (primary stability; PS) and secondary stability (SS) after ossseointegration using RFA, and to investigate the relationship between implant stability and cortical bone thickness. METHODS: In total, 113 patients who attended the Tohoku University Hospital Dental Implant Center were included in this study. A total of 229 implants were placed in either the mandibular region (n = 118) or the maxilla region (n = 111), with bone augmentation procedures used in some cases. RFA was performed in 3 directions, and the lowest value was recorded. The preoperative thickness of cortical bone at the site of implant insertion was measured digitally using computed tomography, excluding cases of bone grafts and immediate implant placements. RESULTS: The mean implant stability quotient (ISQ) was 69.34±9.43 for PS and 75.99±6.23 for SS. The mandibular group had significantly higher mean ISQ values than the maxillary group for both PS and SS (P < 0.01). A significant difference was found in the mean ISQ values for PS between 1-stage and 2-stage surgery (P < 0.5). The mean ISQ values in the non-augmentation group were higher than in the augmentation group for both PS and SS (P < 0.01). A weak positive correlation was observed between cortical bone thickness and implant stability for both PS and SS in all cases (P < 0.01). CONCLUSIONS: Based on the present study, the ISQ may be affected by implant position site, the use of a bone graft, and cortical bone thickness before implant therapy.
Dental Implants ; Humans ; Maxilla ; Osseointegration ; Retrospective Studies ; Transplants

The importance of off the job training in surgical education are widely recognized. The Japanese Board of Cardiovascular Surgery has required a board candidate to do at least 30 hours of off the job training from 2017. U-40 Basic Lecture Course are held annually for young cardiovascular surgeon to learn about basic surgical skills. U-40 Advanced Lecture Course was started to provide opportunity to have more advanced hands-on lecture for young cardiovascular surgeon. However, after the COVID-19 pandemic, the opportunity to hold hands-on seminars are highly limited. In such circumstances, we held a hybrid hands-on seminar. We report details about the hybrid hands-on seminar.

Lenalidomide (LD) was reported to increase the risk of thromboembolism when it was used along with dexamethasone (DEX). Prophylactic administration of antithrombotic drugs against thromboembolism has been recommended for proper use of LD, but none of the recommendation is stated in the package insert. The purpose of this study was to elucidate the usage of acetylsalicylic acid (ASA) for lenalidomide medication in patients withmultiple myeloma. We used the MDV analyzer to investigate clinical data retrospectively. The investigation period was from October 1, 2016 to September 30, 2017. Subjects were outpatients aged 20 years or older who were recorded in clinical data as multiple myeloma. There were 7,590 outpatients with multiple myeloma. They were divided into 4 groups by the combined use situation of LD and DEX: LD/DEX non-use group (n＝5,462), DEX alone group (n＝632),LD alone group (n＝203), and LD/DEX together group (n＝1,293), respectively. The prevalence rate of thromboembolism was 7.3% in the DEX alone group and 16.9% in the LD/DEX together group (p＜0.0001). Among the LD/DEX together group, ASA was prescribed at 63.6% in the group without thromboembolism (n＝1,074). The prevalence rate of thromboembolism was higher in the LD/DEX combined group than in the DEX alone group. Considering these findings, risk management for thromboembolism caused by administration of antithrombotic drugs should be considered. It is necessary to create more evidence concerning the necessity of administration of antithrombotic drug in combination with LD/DEX medication.