ADAM10 inhibits the interaction between IL-17 and HMGB1 in Buerger's disease.

OBJECTIVE: Buerger's disease is a rare disease that causes critical limb ischemia; however, the underlying pathophysiological mechanism remains unclear. Therefore, we investigated the interaction between interleukin (IL)-17 and high-mobility group protein B 1 (HMGB1) and determined whether A disintegrin and metalloproteinase 10 (ADAM10) inhibit this interaction. PATIENTS AND METHODS: The study population included 15 patients with Buerger's disease and 10 healthy donors without a history of giving peripheral blood samples. Cytokine levels were measured using a luminex multiplex assay in plasma. Flow cytometry was used to analyze the subtypes of helper T (Th) cells among peripheral blood mononuclear cells (PBMCs). The effect of ADAM10 on PBMCs was analyzed in vitro. RESULTS: The levels of inflammatory cytokines and production of pathogenic Th cells were found to be higher in Korean patients with Buerger's disease. IL-17 treatment induced HMGB1 associated molecules. HMGB1 also induced IL-17 and Th17 associated transcription factors in Buerger's patients. We observed that ADAM10 regulates the interaction between IL-17 and HMGB1 via advanced glycation end products (RAGE)/nuclear factor-kappa B (NF-kB) pathway in patients with Buerger's disease. CONCLUSIONS: This study suggests that IL-17 and HMGB1 cytokines contribute to the pathogenesis of Buerger's disease. These results indicate that ADAM10 alleviates inflammation in Buerger's disease via the HMGB1 and RAGE/NF-κB signaling pathway and provides insights into the molecular basis of and a potential therapeutic strategy for Buerger's disease.

The Usefulness of Electronic Health Records From Preventive Youth Healthcare in the Recognition of Child Mental Health Problems.

Background and Objectives: Early identification of child mental health problems (MHPs) is important to provide adequate, timely treatment. Dutch preventive youth healthcare monitors all aspects of a child's healthy development. We explored the usefulness of their electronic health records (EHRs) in scientific research and aimed to develop prediction models for child MHPs. Methods: Population-based cohort study with anonymously extracted electronic healthcare data from preventive youth healthcare centers in the Leiden area, the Netherlands, from the period 2005-2015. Data was analyzed with respect to its continuity, percentage of cases and completeness. Logistic regression analyses were conducted to develop prediction models for the risk of a first recorded concern for MHPs in the next scheduled visit at age 3/4, 5/6, 10/11, and 13/14 years. Results: We included 26,492 children. The continuity of the data was low and the number of concerns for MHPs varied greatly. A large number of determinants had missing data for over 80% of the children. The discriminatory performance of the prediction models were poor. Conclusions: This is the first study exploring the usefulness of EHRs from Dutch preventive youth healthcare in research, especially in predicting child MHPs. We found the usefulness of the data to be limited and the performance of the developed prediction models was poor. When data quality can be improved, e.g., by facilitating accurate recording, or by data enrichment from other available sources, the analysis of EHRs might be helpful for better identification of child MHPs.

Mask-induced dermatoses during the COVID-19 pandemic: a questionnaire-based study in 12 Korean hospitals.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, various adverse skin reactions to long-term mask wearing have been reported. AIM: To assess the clinical features of mask-induced dermatoses and to recommend prevention and treatment options. METHODS: From April to August 2020, questionnaires including topics such as demographic information, pre-existing skin disorders, reported mask-related symptoms, daily mask-wearing duration and frequency, types of masks used and whether the participant was a healthcare worker, were distributed to patients in 12 hospitals. Dermatologists assessed skin lesions, confirmed diagnosis and recorded treatments. RESULTS: Itchiness was the most frequent symptom, mostly affecting the cheeks. The most common skin disease was new-onset contact dermatitis (33.94%), followed by new-onset acne (16.97%) and worsening of pre-existing acne (16.97%). Daily wearing of masks was significantly (P = 0.02) associated with new-onset contact dermatitis. More than half of patients with pre-existing skin problems experienced disease worsening while wearing masks. Longer duration of wearing (> 6 h/day, P = 0.04) and use of cotton masks (P < 0.001) significantly increased acne flare-up. Healthcare workers had a higher incidence of skin disease. Skin lesions were generally mild and well tolerated with topical treatment. The study had some limitations: the effect of seasonal characteristics and other risk factors were not assessed, and the patients were visiting dermatological clinics and had interest in their skin status, thus, there may have been selection bias. CONCLUSION: Mask-induced/-triggered dermatoses contribute to increase the dermatological burden during the pandemic.

A study of the microbiological profile of filler-induced skin necrosis.

Skin necrosis is one of the most severe complications following filler injections, and can result in permanent aesthetic defects. Although an increasing number of studies have addressed the management of dermal filler complications, no study has described the spectrum of microbial pathogens. The aim of this study was to delineate the bacterial profile and prognostic factors of filler-related skin necrosis by reviewing the clinical and microbiological features of these patients. A retrospective medical record review of patients undergoing treatment for skin necrosis induced by fillers was conducted. In total, 10 cases were identified, with injection sites being the nasolabial fold (70%; n = 7), nasal dorsum (20%; n = 2) and nasal tip (10%; n = 1). Reviewing the culture results, the true culture-positive rate was found to be 50% after cases of contamination were excluded. To avoid permanent sequelae, all physicians should be aware of possible secondary infections when treating filler-induced skin necrosis.

Analysis of local invasion and regional spread in malignant sublingual gland tumour: Implications for surgical planning.

Malignant tumours arising from the sublingual glands are very rare, and the extent and frequency of local invasion or regional spread in malignant sublingual gland tumour (MSLT) has not been fully studied due to the disease rarity. To provide comprehensive features of local and regional spread of MSLT, we reviewed 20 surgical cases for detailed pathological analyses among 26 cases diagnosed as having primary MSLT. Adenoid cystic carcinoma (ACC) was the most common pathological subtype, followed by mucoepidermoid carcinoma. Disease-free and overall survivals at 5 years were 76.1 % and 77.7 %, respectively. High-grade malignant tumours and grade 2-3 ACC accounted for 41.7 % and 85.7 %. Clinical and pathological extraparenchymal extensions were found in 34.6 % and 80.0 %, respectively. Tumour invasion to the lingual nerve and submandibular gland/ductal system were also detected in 40.0 % and 28.6 %. The incidences of lingual nerve invasion in ACC and ACC ≥4 cm were 30.8 % and 42.9 %. Regional nodal involvement occurred in seven of 26 cases, and all metastatic lymph nodes were found in neck levels Ib and IIa. In summary, a significant portion of MSLT cases consisted of high-grade tumours and grade 2-3 ACC; therefore local invasion into adjacent structures should be cautiously evaluated in cases of MSLT.

Prenylflavonoids isolated from Macaranga tanarius stimulate odontoblast differentiation of human dental pulp stem cells and tooth root formation via the mitogen-activated protein kinase and protein kinase B pathways.

AIM: To identify odontogenesis-promoting compounds and examine the molecular mechanism underlying enhanced odontoblast differentiation and tooth formation. METHODOLOGY: Five different nymphaeols, nymphaeol B (NB), isonymphaeol B (INB), nymphaeol A (NA), 3'-geranyl-naringenin (GN) and nymphaeol C (NC) were isolated from the fruit of Macaranga tanarius. The cytotoxic effect of nymphaeols on human DPSCs was observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The effect of nymphaeols on odontoblast differentiation was analysed with Alizarin Red S staining and odontoblast marker expression was assessed using real-time polymerase chain reaction and Western blot analysis. The molecular mechanism was investigated with Western blot analysis. In order to examine the effect of INB on dentine formation in the developing tooth germ, INB-soaked beads were placed under the tooth bud explants in the collagen gel; thereafter, the tooth bud explant-bead complexes were implanted into the sub-renal capsules for 3 weeks. Tooth root formation was analysed using micro-computed tomography and histological analysis. Data are presented as mean ± standard error (SEM) values of three independent experiments, and results are compared using a two-tailed Student's t-test. The data were considered to have statistical significance when the P-value was less than 0.05. RESULTS: Three of the compounds, NB, INB, and GN, did not exert a cytotoxic effect on human DPSCs. However, INB was most effective in promoting the deposition of calcium minerals in vitro (P < 0.001) and induced the expression of odontogenic marker genes (P < 0.05). Moreover, this compound strongly induced the phosphorylation of mitogen-activated protein (MAP) kinases and protein kinase B (AKT) (P < 0.05). The inhibition of p38 MAP, c-Jun N-terminal kinase (JNK), and AKT substantially suppressed the INB-induced odontoblast differentiation (P < 0.001). In addition, isonymphaeol B significantly induced the formation of dentine and elongation of the tooth root in vivo (P < 0.05). CONCLUSIONS: Prenylflavonoids, including INB, exerted stimulatory effects on odontoblast differentiation and tooth root and dentine formation via the MAP kinase and AKT signalling pathways. These results suggest that nymphaeols could stimulate the repair processes for dentine defects or injuries.

Vesicular glutamate transporter-immunopositive axons that coexpress neuropeptides in the rat and human dental pulp.

AIM: To examine the type of vesicular glutamate transporter (VGLUT)-immunopositive (+) axons that coexpress neuropeptides in the rat and human dental pulp, which may help understand peripheral mechanism of pulpal inflammatory pain in rats and humans. METHODOLOGY: The trigeminal ganglia (TG) and the dental pulp of the maxillary molar teeth from three male Sprague-Dawley rats weighing 300-330 g and dental pulps of three healthy human (male) maxillary premolar teeth from three 16 to 28-year-old patients extracted for orthodontic treatment were used. The type of VGLUT + axons that coexpress substance P (SP)- and/or calcitonin gene-related peptide (CGRP) and parvalbumin in the rat TG and in the axons of the rat and the human dental pulp was examined by double fluorescence immunohistochemistry and quantitative analysis. Results were analyzed using one-way anova and the Kruskal-Wallis test. RESULTS: SP and CGRP were expressed in many human VGLUT1 + pulpal axons but not in the rat VGLUT1 + TG neurons and pulpal axons (P < 0.05). SP and CGRP were expressed in a considerable number of human VGLUT2 + pulpal axons and also in many rat TG neurons and pulpal axons. The fraction of VGLUT1 + axons expressing parvalbumin was about three times higher in the rat than in the human dental pulp (P < 0.05). CONCLUSIONS: These findings suggest that the types of VGLUT + axons, which release neuropeptides, may be different between the rat and the human dental pulp, raising a possibility that peripheral mechanism of pulpal inflammatory pain may be different between rats and humans.

A simple and efficient method of generating HCMV pp65-specific T cells using overlapping peptides.

The methods for expansion of human cytomegalovirus (HCMV)-specific T lymphocytes are limited due to the complex culture process, long culture duration, and human leukocyte antigen (HLA) restriction. Here, we report that in vitro stimulation with pp65 kDa phosphoprotein (pp65)-derived overlapping synthetic peptides rapidly generates large numbers of HCMV-specific cytotoxic T lymphocytes from peripheral blood mononuclear cells (PBMCs) regardless of HLA type. Treatment of PBMCs from healthy volunteers expressing HLA-A*02:01 or HLA-A*24:02 with 138 pp65 overlapping peptides (OLP) resulted in an expansion of HCMV pp65 NLVPMVATV (NLV) pentamer-specific CD8+ T lymphocytes that expressed interferon (IFN)-γ, but the pp65 NLV peptide did not generate HCMV-specific CD8+ T lymphocytes in PBMCs obtained from an HLA-A*24:02 donor due to HLA restriction. The OLP-induced T lymphocytes specific for HCMV derived from PBMCs of HLA-A*02:01- and HLA-A*24:02-expressing donors showed effective cytolytic responses against target cells loaded with OLP or the NLV epitope, but pp65 NLV peptide-induced T lymphocytes did not. Phenotypic analyses demonstrated that OLP increased the frequency of CD3+ CD8+ cells, but not CD3+ CD4+, CD14+, or CD56+ cells, in donor PBMCs. Thus, this study provides evidence that in vitro stimulation with OLP efficiently generates sufficient numbers of HCMV pp65-specific cytotoxic T lymphocytes for adoptive cell therapy. Keywords: human cytomegalovirus; cytotoxic T lymphocyte; overlapping peptides; pp65; cytotoxicity.

Controlling spin current polarization through non-collinear antiferromagnetism.

The interconversion of charge and spin currents via spin-Hall effect is essential for spintronics. Energy-efficient and deterministic switching of magnetization can be achieved when spin polarizations of these spin currents are collinear with the magnetization. However, symmetry conditions generally restrict spin polarizations to be orthogonal to both the charge and spin flows. Spin polarizations can deviate from such direction in nonmagnetic materials only when the crystalline symmetry is reduced. Here, we show control of the spin polarization direction by using a non-collinear antiferromagnet Mn3GaN, in which the triangular spin structure creates a low magnetic symmetry while maintaining a high crystalline symmetry. We demonstrate that epitaxial Mn3GaN/permalloy heterostructures can generate unconventional spin-orbit torques at room temperature corresponding to out-of-plane and Dresselhaus-like spin polarizations which are forbidden in any sample with two-fold rotational symmetry. Our results demonstrate an approach based on spin-structure design for controlling spin-orbit torque, enabling high-efficient antiferromagnetic spintronics.

Comparison of the diagnostic performance of the 2017 and 2018 versions of LI-RADS for hepatocellular carcinoma on gadoxetic acid enhanced MRI.

AIM: To compare the diagnostic performance of the 2017 (v2017) and 2018 versions (v2018) of the Liver Imaging-Reporting and Data System (LI-RADS) for hepatocellular carcinoma (HCC) using gadoxetic acid-enhanced magnetic resonance imaging (Gd-EOB-MRI) and to evaluate the effect in v2018. MATERIALS AND METHODS: Treatment-naive patients at high-risk for HCC who underwent Gd-EOB-MRI were included. The LI-RADS categories were assigned according to v2017 and v2018. The diagnostic performances were compared between v2017 and v2018 according to the size and combination of imaging features. RESULTS: A total of 117 patients with 137 observations were identified, including 89 HCCs; 76.2% (64/84) of observations with threshold growth were re-classified as subthreshold growth when using v2018 instead of v2017. The final categories changed in nine (14%) cases. For the combination of LR-5/LR-5V, there were no significant differences in sensitivity and specificity between the two versions (sensitivity, 64% versus 58.4%; specificity, 87.5% versus 85.4%; all p>0.05). For the combination of LR-4 and LR-5/5V, the diagnostic performance of v2018 was inferior to that of v2017 when considering only major features (accuracy, 86.1% versus 80.3%, respectively; p=0.013), particularly in observations measuring 10-20 mm, but was comparable after adding the ancillary features (accuracy, 86.9% versus 86.1%, respectively; p=1.00). CONCLUSION: In LI-RADS v2018, although a considerable number of observations re-classified subthreshold growth, changes in the assigned categories were insignificant; overall diagnostic performance was comparable to that of v2017, but v2018 might emphasise the value of ancillary features in combination with major features for determining the probability of HCC.

Anisotropic spin-orbit torque generation in epitaxial SrIrO3 by symmetry design.

Spin-orbit coupling (SOC), the interaction between the electron spin and the orbital angular momentum, can unlock rich phenomena at interfaces, in particular interconverting spin and charge currents. Conventional heavy metals have been extensively explored due to their strong SOC of conduction electrons. However, spin-orbit effects in classes of materials such as epitaxial 5d-electron transition-metal complex oxides, which also host strong SOC, remain largely unreported. In addition to strong SOC, these complex oxides can also provide the additional tuning knob of epitaxy to control the electronic structure and the engineering of spin-to-charge conversion by crystalline symmetry. Here, we demonstrate room-temperature generation of spin-orbit torque on a ferromagnet with extremely high efficiency via the spin-Hall effect in epitaxial metastable perovskite SrIrO3 We first predict a large intrinsic spin-Hall conductivity in orthorhombic bulk SrIrO3 arising from the Berry curvature in the electronic band structure. By manipulating the intricate interplay between SOC and crystalline symmetry, we control the spin-Hall torque ratio by engineering the tilt of the corner-sharing oxygen octahedra in perovskite SrIrO3 through epitaxial strain. This allows the presence of an anisotropic spin-Hall effect due to a characteristic structural anisotropy in SrIrO3 with orthorhombic symmetry. Our experimental findings demonstrate the heteroepitaxial symmetry design approach to engineer spin-orbit effects. We therefore anticipate that these epitaxial 5d transition-metal oxide thin films can be an ideal building block for low-power spintronics.

Isostructural metal-insulator transition in VO2.

The metal-insulator transition in correlated materials is usually coupled to a symmetry-lowering structural phase transition. This coupling not only complicates the understanding of the basic mechanism of this phenomenon but also limits the speed and endurance of prospective electronic devices. We demonstrate an isostructural, purely electronically driven metal-insulator transition in epitaxial heterostructures of an archetypal correlated material, vanadium dioxide. A combination of thin-film synthesis, structural and electrical characterizations, and theoretical modeling reveals that an interface interaction suppresses the electronic correlations without changing the crystal structure in this otherwise correlated insulator. This interaction stabilizes a nonequilibrium metallic phase and leads to an isostructural metal-insulator transition. This discovery will provide insights into phase transitions of correlated materials and may aid the design of device functionalities.

Unique Raman Spectroscopic Fingerprints of B-Cell Non-Hodgkin Lymphoma: Implications for Diagnosis, Prognosis and New Therapies.

OBJECTIVE: Raman spectroscopy is a non-invasive laser-based technique that identifies molecular chemical composition of tissues and cells. The objective of the work was to demonstrate that unique Raman spectroscopic fingerprints of B-cell non-Hodgkin lymphoma cells could be distinguished from normal B-cells. METHODS: Normal B-cells and B-cell non-Hodgkin lymphoma cells were mounted on aluminum slides and analyzed by Raman spectroscopy using Asymmetric Least Squares and Principal Component Analysis. RESULTS: Clustering by Principal Component Analysis differentiated normal B-cells from B-cell non-Hodgkin lymphoma cells as well as between the different B-cell non-Hodgkin lymphoma cell types. CONCLUSIONS: Raman spectroscopy technology provided a different paradigm in analyzing tumor cells which could be used for diagnosis as well as contribute new information on unique characteristics of cancer cells to understand pathogenesis and potential novel treatments.

Low rates of osteoporosis treatment after hospitalization for hip fracture in Hawaii.

We evaluated osteoporosis treatment and DEXA utilization rates of patients who were admitted for hip fracture in a single healthcare system in Hawaii from 2015 to 2016. We found that osteoporosis treatment and DEXA utilization rates were low, highlighting a critical gap in osteoporosis care after admission for hip fracture. INTRODUCTION: The objective of this study was to evaluate osteoporosis care after an admission for hip fracture at three community hospitals within a single healthcare system in Hawaii. METHODS: A retrospective chart review was conducted (n = 428) of patients ≥ 50 years and hospitalized for hip fractures between January 1, 2015, and May 31, 2016, at three major hospitals within Hawaii Pacific Health, a large healthcare system in Hawaii. Basic demographics were collected, and medications prescribed were quantified and described within 1 year of hip fracture. Logistic regression was used to evaluate the association between collected variables and the odds of osteoporosis treatment. RESULTS: Only 115 (26.9%) patients were prescribed a medication for osteoporosis as a secondary prevention within a year of hospitalization for hip fracture. DEXA scans were performed in 137 (32.0%) patients. Most of the treated patients were prescribed oral bisphosphonates. Treatment facility, female gender, and higher BMI were found to be predictive factors for osteoporosis treatment. CONCLUSION: The use of osteoporosis medication for secondary prevention after admission for hip fracture in Hawaii is low. Efforts need to be made to improve treatment rates, especially among males.

Identification of small droplets of photosynthetic squalene in engineered Synechococcus elongatus PCC 7942 using TEM and selective fluorescent Nile red analysis.

To identify microbial squalene that has been widely used in various industrial applications, intracellular formation of photosynthetic squalene was investigated using the previously engineered Synechococcus elongatusPCC 7942 strain. Unlike the proposed localization of squalene in the membrane bilayer, small droplets were identified in the cytoplasm of S. elongatusPCC 7942 as squalene using transmission electron microscopy analysis. Determination of the diameters of the squalene droplets with manual examination of 1016 droplets in different squalene-producing strains indicated larger squalene droplets in larger cells. Based on the observation of a sole droplet of squalene in a cyanobacterium, fluorescent Nile red was used for the selective staining of squalene. The fluorescent intensities were correlated with squalene contents determined using gas chromatography-mass spectrometry. Photosynthetic squalene was identified as a small droplet in S. elongatusPCC 7942, and this noninvasive quantitative method could be useful to promote high-throughput strain development for squalene production. SIGNIFICANCE AND IMPACT OF THE STUDY: Engineering of Cyanobacteria has focused on sustainable production of squalene by converting CO2 . Before improving the photosynthetic squalene production, we characterized formation of squalene, showing small droplets in the cytoplasm instead of single granule. Based on the finding and the analysis, this study has provided valuable evidences how further metabolic engineering strategies should apply to enhance the production yield.

The distribution of calbindinD-28k and parvalbumin immunoreactive neurons in the somatosensory area of the pigeon pallium.

GABAergic interneurons regulate the degree of glutamatergic excitation and output of projection neurons. In this study, we investigated the distribution of calbindinD-28k (CB) and parvalbumin (PV) in the somatosensory area of the pigeon pallium using immunohistochemical method. Our results show that anatomical structures of the somatosensory area of the pigeon pallium consisted of several subdivisions including the hyperpallium, intercalated hyperpallium, mesopallium, nidopallium and basorostralis. Neuronal density was significantly higher in the intercalated hyperpallium and basorostralis than that in the other subdivisions. The density of the CB immunoreactive neurons was generally similar in all the subdivisions; however, the density of PV immunoreactive neurons was particularly prominent in the basorostralis compared with that in the other subdivisions. In addition, the mean proportion of PV immunoreactive neurons to total neurons was higher than that in the CB immunoreactive neurons in all the subdivisions. In brief, our present study shows that PV immunoreactive neurons in the somatosensory area of the pigeon pallium were significantly abundant compared with CB immunoreactive neurons. This finding needs more studies regarding CB- and PV-related functions in the somatosensory area of the avian pallium.

Oral cancer: A multicenter study.

BACKGROUND: To determine the prevalence and clinicopathologic features of the oral cancer patients. MATERIAL AND METHODS: Biopsy records of the participating institutions were reviewed for oral cancer cases diagnosed from 2005 to 2014. Demographic data and site of the lesions were collected. Sites of the lesion were subdivided into lip, tongue, floor of the mouth, gingiva, alveolar mucosa, palate, buccal/labial mucosa, maxilla and mandible. Oral cancer was subdivided into 7 categories: epithelial tumors, salivary gland tumors, hematologic tumors, bone tumors, mesenchymal tumors, odontogenic tumors, and others. Data were analyzed by descriptive statistics using SPSS software version 17.0. RESULTS: Of the 474,851 accessioned cases, 6,151 cases (1.30%) were diagnosed in the category of oral cancer. The mean age of the patients was 58.37±15.77 years. A total of 4,238 cases (68.90%) were diagnosed in males, whereas 1911 cases (31.07%) were diagnosed in females. The male-to-female ratio was 2.22:1. The sites of predilection for oral cancer were tongue, labial/buccal mucosa, gingiva, palate, and alveolar mucosa, respectively. The three most common oral cancer in the descending order of frequency were squamous cell carcinoma, non-Hodgkin lymphoma and mucoepidermoid carcinoma. CONCLUSIONS: Although the prevalence of oral cancer is not high compared to other entities, oral cancer pose significant mortality and morbidity in the patients, especially when discovered late in the course of the disease. This study highlights some anatomical locations where oral cancers are frequently encountered. As a result, clinicians should pay attention to not only teeth, but oral mucosa especially in the high prevalence area as well since early detection of precancerous lesions or cancers in the early stage increase the chance of patient being cured and greatly reduce the mortality and morbidity. This study also shows some differences between pediatric and elderly oral cancer patients as well as between Asian and non-Asian oral cancer patients.

Solid pseudopapillary neoplasm of the pancreas with liver metastasis initially misinterpreted as benign haemorrhagic cyst.

Solid pseudopapillary neoplasm (SPN) of the pancreas is considered a low-malignant neoplasm with a good prognosis. However, 5% to 15% of patients with SPNs develop metastatic disease, most commonly in the liver. Metastatic hepatic malignancies that show pseudocystic features are rare. Here we describe the case of a middle-aged female with a cystic liver metastasis from SPN. To the best of our knowledge, SPN with a single cystic liver metastasis has not been described, although these tumours frequently undergo haemorrhagic-cystic degeneration. Thus, in these patients the marked cystic change could be misinterpreted as a benign lesion.

The location of projection neurons to the biceps brachii muscle in the telencephalon of the pigeon.

Few studies regarding the anatomical distribution of motor neurons innervating muscles of the arm have been demonstrated in avian brains. The purpose of this study was to finely determine the localization of cerebral neurons innervating the biceps brachii muscle in the pigeon. The cholera toxin B subunit (CTB) was employed as a retrograde tracer to determine the location of neurons controlling the biceps brachii muscle in the telencephalon following intramuscular injection in male pigeons (n = 7), which were killed 14 days after intramuscular injection with CTB. We found that CTB-labelled neurons were located contralaterally in the hyperpallium apicale of the rostral telencephalon and that most of the CTB-labelled neurons were pyramidal in shape. This study shows that CTB is easily taken up by nerve terminals which innervate the biceps brachii muscle of the pigeon and that cerebral motor neurons controlling the biceps brachii muscle are located in the hyperpallium apicale.