• Title/Summary/Keyword: Muscle spindle

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MORPHOLOGY OF THE TERMINAL ARBORS FROM THE MASSETERIC MUSCLE SPINDLE AFFERENTS IN THE TRIGEMINAL MOTOR NUCLEUS (삼차신경 운동핵에서 교근 근방추 구심성 신경섬유 종말지의 미세구조)

  • Lee, Kyung-Woo;Bae, Yong-Chul;Kim, Chin-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.16 no.3
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    • pp.321-347
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    • 1994
  • Muscle spindle afferents from masseter muscle were labelled by the intra-axonal HRP injection and were processed for light microscopic reconstruction. Regions containing terminal arbors scattered in the central portion of the masseteric motor neuron pool (type I a) and those restricted to 2-3 small portion of it (type II) were selected and processed for electronmicroscopic analysis with serial sections. The shape of the labelled boutons was dome or elongated shape. Scalloped or glomerulus shape with peripherial indentation containing pre or postsynaptic neuronal propiles, which is occasionally found in the trigeminal main sensory nucleus and spinal dorsal horn, was not observed. Both type Ia and type II boutons had pale axoplasm and contained clear, spherical vesicles of uniform size(dia : 49-52nm) and occasionally large dense cored vesicles(dia : 87-118nm). The synaptic vesicles were evenly distributed throughout the boutons although there was a slight tendency of vesicles to accumulate at the presynaptic site. The average of short and long diameter(short D. + long D./2) of type I a bouton was smaller than that of type II bouton. All the labelled boutons, which showed prominent postsynaptic density, large synaptic area and multiple synaptic contact, made asymmetrical synaptic contact with postsynaptic neuronal propiles. Most of the type Ia and type II boutons made synaptic contact with only one neuronal propile and boutons which shows synaptic contact or more neuronal propiles was not observed. Most of the type Ia boutons(87.2%) were presynaptic to the soma or proximal dendrite and a few remainder(12.8%) made synaptic contact with dendritic shaft or distal dendrite. In contrast, majority of type II boutons showed synaptic contact with dendritic shaft and remainder with soma or proximal dendrite. In conclusion, terminal boutons which participate in the excitatory monosynaptic jaw jerk reflex made synaptic contact with more proximal region of the neuron, and showed very simple synaptic connection, compared with those from the primary afferenst in the other region of the central nervous system such as spinal dorsal horn and trigeminal main sensory nucleus which assumed to be responsible for the mediating pain, tactile sensation, sensory processing or sensory discrimination.

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Impulse Trafficking in Neurons of the Mesencephalic Trigeminal Nucleus

  • Saito, Mitsuru;Kang, Young-Nam
    • International Journal of Oral Biology
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    • v.31 no.4
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    • pp.113-118
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    • 2006
  • In the primary sensory neuron of the mesencephalic trigeminal nucleus (MTN), the peripheral axon supplies a large number of annulospiral endings surrounding intrafusal fibers encapsulated in single muscle spindles while the central axon sends only a few number of synapses onto single ${\alpha}-motoneurons({\alpha}-MNs)$. Therefore, the ${\alpha}-{\gamma}$ linkage is thought to be very crucial in the jaw-closing movement. Spike activity in a ${\gamma}-motoneuron\;({\gamma}-MN)$ would induce a large number of impulses in single peripheral axons by activating many intrafusal fibers simultaneously, subsequently causing an activation of ${\alpha}-MNs$ in spite of the small number of synapses. Thus, the activity of ${\gamma}-MNs$ may be vital for modulation of jaw-closing movements. Independently of such a spindle activity modulated by ${\gamma}-MNs$, somatic depolarization in MTN neurons is known to trigger the oscillatory spike activity. Nevertheless, the trafficking of these spikes arising from the two distinct sources of MTN neurons is not well understood. In this short review, switching among multiple functional modes of MTN neurons is discussed. Subsequently, it will be discussed which mode can support the ${\alpha}-{\gamma}$ linkage. In our most recent study, simultaneous patch-clamp recordings from the soma and axon hillock revealed a spike-back-propagation from the spike-initiation site in the stem axon to the soma in response to a somatic current pulse. The persistent $Na^+$ current was found to be responsible for the spike-initiation in the stem axon, the activation threshold of which was lower than those of soma spikes. Somatic inputs or impulses arising from the sensory ending, whichever trigger spikes in the stem axon first, would be forwarded through the central axon to the target synapse. We also demonstrated that at hyperpolarized membrane potentials, 4-AP-sensitive $K^+$ current ($IK_{4-AP}$) exerts two opposing effects on spikes depending on their origins; the suppression of spike initiation by increasing the apparent electrotonic distance between the soma and the spike-initiation site, and the facilitation of axonal spike invasion at higher frequencies by decreasing the spike duration and the refractory period. Through this mechanism, the spindle activity caused by ${\gamma}-MNs$ would be safely forwarded to ${\alpha}-MNs$. Thus, soma spikes shaped differentially by this $IK_{4-AP}$ depending on their origins would reflect which one of the two inputs was forwarded to the target synapses.

Effects of High-heel Shoes on EMG Activities of Rectus Femoris and Biceps Femoris (신발 굽의 높이와 신발착용기간이 대퇴근육 활동량에 미치는 영향)

  • Park, Eun-Young;Kim, Won-Ho;Kim, Gyoung-Mo;Cho, Sang-Hyun
    • Physical Therapy Korea
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    • v.6 no.2
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    • pp.32-42
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    • 1999
  • This study was conducted to identify the effects of high-heel shoes on EMG activities of rectus femoris and biceps femoris in 28 healthy women. Subjects were composed of experimental group (wearing high-heel shoes) and control group (wearing low-heel shoes). Two groups participated in three conditions standing (bare foot wearing athletic shoes and 7.5 cm height shoes). In high-heel shoes condition, EMG activities of rectus femoris of control group were significantly lower than that of biceps femoris of experimental group, but EMG activities of both muscles of experimental group did not should significant difference. In bare foot standing condition, EMG activities of rectus femoris of experimental group were significantly lower than that of biceps femoris but EMG activities of both muscles of control group had no significant difference. These results showed that hamstring lengthening effects was produced when wearing high-heel shoes because the external knee extension moment was increased. In the short term, high-heel shoes effect on the increase of the biceps femoris activities by spindle reflex, but in the long term, the normal amplitude of the same muscle activities by Golgi tendon organ reflex.

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Calcifying Fibrous Tumor Mimicking a Foreign Body of the Stomach: A Case Report (위 내 이물로 오인한 석회화 섬유 종양 1예)

  • Jeong, Ji-Eun;Lee, Kyung-Hun;Sung, Hyun-Jung;Cho, Chang-Ho
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.1
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    • pp.57-63
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    • 2009
  • Calcifying fibrous tumors (CFTs) are unusual benign tumors of childhood, located primarily in soft tissues, pleura, and peritoneum. The cause and pathogenesis are unclear. We report a rare case of a CFT in a 2-year-old boy who presented with vomiting and abdominal distension. An abdominal X-ray showed an elliptical, calcific shadow in the LUQ area mimicking a foreign body. An internally protruding mass along the lesser curvature of the gastric body was an incidental finding during upper endoscopy, biopsies of which were negative. Abdominal CT showed a 4.5${\times}$3.2 cm soft tissue mass of the gastric wall with calcifications. A diagnosis of gastric submucosal mass was suspected and a wedge resection of the stomach was performed. On microscopic examination, the tumor was composed of whorls of dense hyalinized collagen bundles with a few fibroblasts. There were also amorphous dystrophic calcifications and nodular aggregates of mononuclear inflammatory cells. Immunohistochemically, spindle cells did not stain for anaplastic lymphoma kinase-1 (ALK-1), CK, smooth muscle actin (SMA), or desmin. Taken together, the mass was compatible with a CFT of the gastric wall. This is the first reported case of CFT in a Korean child.

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Multiple Pulmonary Benign Metastasizing Leiomyoma (다발성으로 폐에 발생한 양성 전이성 평활근종)

  • Chun, Joon-Kyung;Lee, Kyo-Seon;Song, Sang-Yun;Ahn, Byoung-Hee;Na, Kook-Ju
    • Journal of Chest Surgery
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    • v.40 no.11
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    • pp.789-792
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    • 2007
  • We report here a case of pulmonary benign metastasizing leiomyoma from the uterus in a 45 year old woman. The patient presented for investigation of multiple pulmonary nodules on a routine chest roentgenogram. The patient had undergone uterine myomectomy due to uterine leiomyoma 10 years earlier. We performed thoracoscopic wedge resection for definitive diagnosis. Histologically, spindle shaped smooth muscle cells appeared between collagen stroma, histology similar to that seen in uterine myoma. The tumor tissue tested positive for estrogen and progesterone receptors. The pathological findings were consistent with benign metastasizing leiomyoma. The patient was in pre-menopause. She received no specific treatment for lung tumors, and we did not found any changes in the lesions after one year follow up without any medication.

A Case of Gastric Schwannoma (위 신경초종 1예)

  • Choi Jae Hyuck;Chang Weon Young;Huh Jin Suk;Noh Jae Hyung;Sohn Tae Sung;Choi Sung Ho;Kim Sung;Kim Yong Il
    • Journal of Gastric Cancer
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    • v.2 no.2
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    • pp.101-104
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    • 2002
  • Schwannoma of the stomach is a rare controversial neoplasm which requires extensive studies to clarify its nature as a stromal tumor or leiomyoma. We describe the pathologic, immunohistochemical, and ultrastructural characteristics of schwannoma of the stomach in a 33-year-old woman. The tumor was a well-circumscribed submucosal mass located in the posterior wall of the midbody of the stomach. Microscopically, the cells were made up of fasciculating bundles of spindle cells featured with peripheral lymphoid cell cuffing. The tumor cells revealed a diffuse, strong immunoreactivity to S-100 protein and vimentin, but were negative to desmin and smooth muscle actin. They also had a focal positive reaction to glial fibrillary acidic protein. Ultrastructurally, many tumor cells showed a number of thin, elongated and interdigitating dendritic-cell-like processes, distinctly uniformed basal laminae, frequent cellular attachments, and microfilaments. These findings support the schwannian nature of the tumor.

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Benign Metastasizing Pulmonary Leiomyoma with Hemoptysis (객혈을 동반한 양성 전이성 폐 평활근종 1예)

  • Park, So Young;Lim, Eun Ju;Jang, Ji-Sun;Kim, Chang-Hwan;Jee, Hyun Keun;Cho, Sung Jin;Park, Yong Bum;Lee, Jae Young;Mo, Eun Kyung
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.1
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    • pp.92-96
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    • 2006
  • A benign metastasizing pulmonary leiomyoma(BMPL) is a rare disease that is usually detected years after a hysterectomy or myomectomy. Despite the benign pathological appearance, these tumors can metastasize and become clinically malignant. Recently, we experienced case of BMPL with hemoptysis. A 43-year-old woman, who had undergone a hysterectomy due to uterine leiomyoma 8 years ago, visited our department complaining of intermittent hemoptysis. A chest CT showed bilateral multiple nodular lesions. Video-associated thoracoscopy was performed. The resected small nodular lesion revealed the proliferation of spindle cells without mitosis or nuclear atypism. The lesions tested positive to the smooth muscle marker (actin) by immunohistochemical staining. Therefore, the multiple nodules were considered as benign metastasizing pulmonary leiomyoma from a uterine leiomyoma. GnRH analogue therapy was initiated. A chest CT showed that the size and number of pulmonary lesions did not change after 3 months, and the patient was symptom free.

Endoscopic Ultrasound-Guided Fine Needle Aspiration Cytology in the Diagnosis of a Gastrointestinal Stromal Tumor of the Stomach -A Case Report - (내시경 초음파 유도하에 세침흡인 세포검사로 진단한 위의 위장관 기질 종앙 1예 보고)

  • Kim, Lucia;Kim, Hyung-Gil;Chu, Young-Chae;Park, In-Suh;Choi, Suk-Jin;Han, Jee-Young;Kim, Sun-Hee;Lee, Don-Haeng;Kim, Joon-Mee
    • The Korean Journal of Cytopathology
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    • v.19 no.2
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    • pp.178-182
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    • 2008
  • We report here a case of a gastrointestinal stromal tumor (GIST) in the stomach that was diagnosed by endoscopic ultrasound-guided fine needle aspiration cytology (EUS-FNA). A 67 year old male patient underwent regular check-ups for five years due to the presence of a submucosal tumor that was found in the fundus of the stomach incidentally. EUS-FNA was performed to evaluate the tumor, which had increased in size from 1 cm to 2.8cm. A cytologic smear revealed cohesive sheets or clusters of spindle cells with elongated nuclei. Immunohistochemical staining revealed a strong positive reaction for c-kit and CD34, without any reaction for smooth muscle actin and Ki-67. Therefore, a diagnosis of GIST was made.

Multiple Cutaneous Leiomyoma Derived from the Mutation in Fumarate Hydratase Gene: A Case Report (푸마르산 수산화효소 유전자 결함에 따른 다발성 피부 평활근종의 치험례)

  • Kim, Yoong Soo;Tak, Kyoung Seok;Cho, Chung Nam;Chung, Chan Min;Oh, Suk Joon;Lee, Min Jin
    • Archives of Plastic Surgery
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    • v.34 no.5
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    • pp.659-662
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    • 2007
  • Purpose: Multiple skin leiomyoma and uterine myoma bearing autosomal dominant traits are benign smooth muscle tumors which originate in skin or female uterus. Skin leiomyoma occurs after gene mutation originating from arrector pili muscle of hair follicle where its clinical manifestations vary significantly from person to person. Our department hereby reports the histological findings and genetic evaluations of this very rare disease. Methods: A 57-year-old woman presented in our institute with multiple tumors in the left and central parts of her back that started to appear since 19 years ago. The patient was diagnosed as having uterine myoma 15 years ago and underwent hysterectomy. Biopsy has been done on the specimen, and genomic DNA was separated from Fumarate hydratase gene for it to go through PCR amplification. The results of PCR amplification were aligned by sequencer. Results: According to the results of biopsy, tumor cells were spindle-shaped and were aligned in a bundle where there was no dysplasia or mitosis. Moreover, these cells had abundant eosinophilic cytoplasm with elongated nucleus, and benign leiomyoma that showed positive reactions to SMA stain were found. In genetic examination, mutations such as heterozygous single nucleotide substitutions were found in alignments of amplified DNA. Conclusion: Multiple skin leiomyoma and uterine myoma are relatively uncommon diseases that are transmitted through autosomally dominant traits from genetic mutations. When a patient's chief complaint lies upon skin-colored or brown masses that occur in multiples appearing in the trunk or extremities with characteristic clinical symptoms and histological findings, and when the patient's family history is acknowledged such as skin or uterine leiomyoma or renal tumor, necessary genetic examination on multiple skin leiomyoma and uterine myoma could be done, and thereby precise diagnosis could also be made.

A Case of Benign Metastasizing Leiomyoma in the Lung (양성 전이성 폐 평활근종 1예)

  • Hwang, Jae-Kyung;Park, Kae-Young;Park, Jeong-Woong;Park, Jae-Kyung;Jeong, Seong-Hwan;Suh, Jun-Bum;Lee, Han-Kyung;Lee, Jae-Woong;Oh, Young-Ha;Nam, Gui-Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.2
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    • pp.231-236
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    • 2000
  • Benign metastasizing leiomyoma usually occurs in women and is associated with a past hysterectomy in 80% of the cases, which is a rare entity. The patient was a 39-year-old woman who complained of cough and sputum. She underwent hysterectomy because of benign leiomyoma ten years ago. Chest X-ray showed nodular lesion in the left lung field. Chest CT showed a 3cm sized round well defined mass at left hilum with mild indentation of segmental bronchi of left upper lobe and a small tiny nodule in right lower lung field. Nodular lesion of left upper 1000 was resected by thoracotomy. Pathological evaluation showed benign spindle-like cells having nuclei without cytotic atypia similar to those of benign leiomyoma. Immunohistochernical stainings for desmin and smooth muscle actin were positive. Therefore these nodules are considered as benign metastasizing leiomyoma from a uterine leiomyoma. We report this case with the review of literature.

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