• International Journal of Oral Biology
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• v.32 no.4
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• pp.153-160
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• 2007

The superficial dorsal horn, particularly substantia gelatinosa (SG) in the spinal cord, receives inputs from small-diameter primary afferents that predominantly convey noxious sensation. Reactive oxygen species (ROS) are toxic agents that may be involved in various neurodegenerative diseases. Recent studies indicate that ROS are also involved in persistent pain through a spinal mechanism. In the present study, whole cell patch clamp recordings were carried out on SG neurons in spinal cord slice of young rats to investigate the effects of hydrogen peroxide on neuronal excitability and excitatory synaptic transmission. In current clamp condition, tert-buthyl hydroperoxide (t-BuOOH), an ROS donor, depolarized membrane potential of SG neurons and increased the neuronal firing frequencies evoked by depolarizing current pulses. When slices were pretreated with phenyl-N-tert-buthylnitrone (PBN) or ascorbate, ROS scavengers, t-BuOOH did not induce hyperexcitability. In voltage clamp condition, t-BuOOH increased the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs), and monosynaptically evoked excitatory postsynaptic currents (eEPSCs) by electrical stimulation of the ipsilateral dorsal root. These data suggest that ROS generated by peripheral nerve injury can modulate the excitability of the SG neurons via pre- and postsynaptic actions.

• Annals of Clinical Neurophysiology
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• v.13 no.2
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• pp.101-105
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• 2011

Neurolymphomatosis, an uncommon manifestation of non-Hodgkin's lymphoma, is lymphomatous infiltration of peripheral nerves. We confirmed the diagnosis of neurolymphomatosis in a 75-year old woman with a history of complete remission of diffuse large B cell type lymphoma on the nasal cavity seven years ago. She complained of painful weakness of left leg and took the electrophysiologic study, extremity ultrasonography, fluorodeoxyglucose PET-CT, and extremity MRI serially. She was diagnosed as neurolymphomatosis by targeted posterior tibial nerve mass biopsy.

• The Korean Journal of Pain
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• v.26 no.2
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• pp.177-180
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• 2013

Trigeminal neuralgia (TN) is characterized by recurrent paroxysms of unilateral facial pain that typically is severe, lancinating, and activated with cutaneous stimulation. There are two types of TN, classical TN and atypical TN. The pain nature of classical TN are the same as those described above, whereas atypical TN is characterized by constant, burning pain. We describe the case of a 49-year-old male presenting with right-sided facial pain. The patient was diagnosed with temporomandibular joint disorder at a dental clinic and was on medical treatment, but his symptoms worsened gradually. He was referred to our pain clinic for further evaluation. Radiologic evaluation, including MRI, showed a parapharyngeal tumor. For the relief of TN, a right mandibular nerve (V3) root block was performed at our pain clinic, and then he was scheduled for radiation and chemotherapy.

• Applied Microscopy
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• v.28 no.4
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• pp.563-575
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• 1998

To investigate the changes during the differentiation of the cerebral neurons of chick embryo of tne embryogenic day (ED) 7 and 8, the ultrastructural changes in the cerebral neurons, the activity of dehydronases (LDH, MDH and SDH), protein expression profile and adenosine triphosphate concentration were analyzed. In ED 7 chick embryos, relatively large nucleus, centrally located nucleolus, evenly spread chromatin over nucleoplasm, and prominent nuclear envelope were observed. Oval-shaped mitochondria with well-developed cristae were present over entire cytoplasm. In ED 8 chick embryos, evenly spread chromatin over nucleoplasm, and prominent nuclear envelope were observed. In the cytoplasm, well-developed rough endoplasmic reticulum and Golgi complex were observed. In ED 7 chick embryos and ED 8 chick embryos, 31 polypeptide bands and 34 polypeptide bands were observed, respectively. The activities of dehydrogenases were lower in ED 7 chick embryos than in ED 8 chick embryos. LDH activity was 8.16 (ED 7) and 9.28 (ED 8), MDH activity was 7.98 (ED 7) and 10.10 (ED 8), and SDH activity was 5.49 (ED 7) and 7.14 (ED 8) respectively. The ATP concentration remained unchanged over ED 7 and 8.

• The Korean Journal of Pain
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• v.35 no.2
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• pp.160-172
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• 2022

Background: The authors established an in vitro model of diabetic neuropathy based on the culture system of primary neurons and Schwann cells (SCs) to mimic similar symptoms observed in in vivo models of this complication, such as impaired neurite extension and impaired myelination. The model was then utilized to investigate the effects of insulin on enhancing neurite extension and myelination of diabetic neurons. Methods: SCs and primary neurons were cultured under conditions mimicking hyperglycemia prepared by adding glucose to the basal culture medium. In a single culture, the proliferation and maturation of SCs and the neurite extension of neurons were evaluated. In a co-culture, the percentage of myelination of diabetic neurons was investigated. Insulin at different concentrations was supplemented to culture media to examine its effects on neurite extension and myelination. Results: The cells showed similar symptoms observed in in vivo models of this complication. In a single culture, hyperglycemia attenuated the proliferation and maturation of SCs, induced apoptosis, and impaired neurite extension of both sensory and motor neurons. In a co-culture of SCs and neurons, the percentage of myelinated neurites in the hyperglycemia-treated group was significantly lower than that in the control group. This impaired neurite extension and myelination was reversed by the introduction of insulin to the hyperglycemic culture media. Conclusions: Insulin may be a potential candidate for improving diabetic neuropathy. Insulin can function as a neurotrophic factor to support both neurons and SCs. Further research is needed to discover the potential of insulin in improving diabetic neuropathy.

• Archives of Plastic Surgery
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• v.49 no.6
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• pp.724-728
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• 2022

Various flaps are used to reconstruct skin and soft tissue defects of the vulva following resection of malignancies. Whenever possible, reconstruction using local flaps is the standard treatment. Here, we describe vulvar defect reconstruction using keystone flaps. Standard keystone flaps are based on randomly located vascular perforators. However, we designed a keystone flap that includes perforators of three named arteries (the anterior labial artery of the external pudendal artery, cutaneous branches of the obturator artery, and posterior labial artery of the internal pudendal artery) and the pudendal nerve, which accompanies the internal pudendal artery. Four patients with squamous cell carcinoma and extramammary Paget's disease of the vulva underwent radical vulvectomy and keystone flaps including perforators of three arteries. Depending on the morphology of the defects, keystone flaps were used with different designs. For elliptical and unilateral vulvar defects, a standard keystone flap was designed, and for defects on both sides of the vulva, a double opposing keystone flap was used. For oval defects, the omega variant keystone flap was designed, and when the morphology of the defect needed rotation of the flap, a rotational keystone flap was designed. All the patients showed good function and sensation, with an acceptable cosmetic appearance.

• Natural Product Sciences
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• v.28 no.1
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• pp.1-5
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• 2022

Two 2H-1-benzopyran derivatives, methyl 8-hydroxy-2,2-dimethyl-2H-1-benzopyran-5-carboxylate (1) and methyl 8-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carboxylate (2), including a new compound (1) were isolated from the twigs of Chaenomeles sinensis. Their chemical structures were characterized based on analysis of NMR data including ¹H and ¹³C, COSY, HSQC, and HMBC and HRMS data. The isolated compounds (1 and 2) were assessed for their anti-neuroinflammatory activity by measuring inhibition levels of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells and for their neurotrophic activity by the secretion of nerve growth factor (NGF) in C6 cells. Compounds 1 and 2 exhibited powerful anti-neuroinflammatory effects with IC₅₀ values of 17.14 and 19.30 μM, respectively, without cell toxicity, and also showed moderate effects on the stimulation of NGF secretion levels with 113.15 ± 3.54 and 130.20 ± 8.03%, respectively. The biosynthetic pathway of 1 and 2 was proposed that they would be derived from a protocatechuic acid and an isoprenyl unit.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.84-89
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• 2019

Schwannomas are benign neoplasms with a Schwann cell origin. A plexiform schwannoma is a rare variant of a schwannoma with a plexiform or multinodular growth pattern. The condition occurs mostly as a solitary lesion in the skin or subcutaneous tissue, or uncommonly located in the deep soft tissue. We report a rare case of recurred multiple plexiform schwannomas arising from the posterior tibial nerve and its branch, which was located in a deep anatomic location and accompanied by a bony deformity.

• Journal of Yeungnam Medical Science
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• v.40 no.4
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• pp.328-334
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• 2023

An aging population and changes in dietary habits have increased the incidence of diabetes, resulting in complications such as diabetic foot ulcers (DFUs). DFUs can lead to serious disabilities, substantial reductions in patient quality of life, and high financial costs for society. By understanding the etiology and pathophysiology of DFUs, their occurrence can be prevented and managed more effectively. The pathophysiology of DFUs involves metabolic dysfunction, diabetic immunopathy, diabetic neuropathy, and angiopathy. The processes by which hyperglycemia causes peripheral nerve damage are related to adenosine triphosphate deficiency, the polyol pathway, oxidative stress, protein kinase C activity, and proinflammatory processes. In the context of hyperglycemia, the suppression of endothelial nitric oxide production leads to microcirculation atherosclerosis, heightened inflammation, and abnormal intimal growth. Diabetic neuropathy involves sensory, motor, and autonomic neuropathies. The interaction between these neuropathies forms a callus that leads to subcutaneous hemorrhage and skin ulcers. Hyperglycemia causes peripheral vascular changes that result in endothelial cell dysfunction and decreased vasodilator secretion, leading to ischemia. The interplay among these four preceding pathophysiological factors fosters the development and progression of infections in individuals with diabetes. Charcot neuroarthropathy is a chronic and progressive degenerative arthropathy characterized by heightened blood flow, increased calcium dissolution, and repeated minor trauma to insensate joints. Directly and comprehensively addressing the pathogenesis of DFUs could pave the way for the development of innovative treatment approaches with the potential to avoid the most serious complications, including major amputations.

• Anatomy and Cell Biology
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• v.56 no.4
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• pp.482-493
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• 2023

Understanding the anatomy of suprascapular area helps the clinicians and surgeons in management of any disability at the shoulder region. This work aimed to clear the different morphological and morphometrical types of suprascapular notch (SSN). Unknown 120 dry human scapulae of both sides and 60 formalin-embalmed cadaveric upper limbs (40 males and 20 females) were used in the present study. Three main morphological forms of SSN were reported: J, U, and V-shaped. J-shaped notch showed the highest incidence followed by U-shaped then V-shaped one. Morphometrically, type (III) notch was the most prevalent in both dry bones and cadavers, while the incidence of type (II) was the lowest form. Also, the measurements of superior transverse diameter, middle transverse diameter and vertical dimension of the different types of the notch showed no side or sex significant difference. The suprascapular foramen with ossified superior transverse scapular ligament (STSL) was seen in 5.8% of dry bones and 10% of cadaveric specimens. Fan and band-shaped ossified transverse scapular ligaments were reported. Absence of SSN was seen in 10.8% of dry bones, 7.5% of male and 10% of female specimens with left side predominance. V-shaped, absence, and ossified STSL were considered as predisposing factors of suprascapular nerve entrapment syndrome. Knowledge of the morphology and morphometric parameters of SSN is of great clinical significance for anatomists, radiologists, physiotherapists, orthopedics and neurosurgeons to perform good diagnosis and best planning for surgical or arthroscopic interventions within the shoulder region.