Piezoelectricity of bone and electrical callus

AbstractThe year 2012 is the 60th anniversary of the discoveries of the piezoelectricity of bone and electrical callus, which were reported by Dr. Iwao Yasuda of our department for the first time in 1953, only 8years after the end of World War II. The historians of the Japanese Orthopaedic Association have designated these accomplishments as “a great and proud Japanese achievement for orthopedics”. Amazingly, Dr. Yasuda carried out these studies while facilities and human resources were extremely lacking. His frontier spirit must have encouraged young researchers to overcome difficulties and develop innovative ideas. I believe that his outstanding creativity had been partly brought about by the fact that he was studying in Kyoto

<原著>軟骨細胞の分化における HSP70 の発現

To know the role of HSP70 in chondrocytes, HSP70 expressions under heat stress or in a nonstress condition were examined by using electrophoresis, immunohistochemistry, and in situ hybridization. As a result, HSP70 was observed in proliferating chondrocytes in the micro-mass cultures without heat stress. In this culture, chondrocytes maintained the terminal differentiation potency. On the other hand, HSP70 did not appear in the chondrocytes in the logarithmic growth phase of the monolayer culture. In growth plates in vivo, HSP70 expressions in the chondrocytes located in the resting and hypertrophic zones were observed with immunohistochemistry. Appearance of HSP70 mRNA was also confirmed by in situ hybridization in the proliferating zone of growth plate. HSP70 can be expressed not only in chondrocytes under heat stress but also in the cells without stress, and the expression would be related to the terminal differentiation of chondrocytes. HSP70 is surmised to promote hypertrophy and calcification by stopping protein synthesis in chondrocytes which possess terminal differentiation potency.軟骨細胞との関連が注目されている熱ショック蛋白質の発現を, 遠沈管培養軟骨細胞と骨端軟骨板を用いて, in vitro および in vivo で検索した. 温熱ストレス下のラﾂト軟骨細胞では, 少なくとも3種類の熱ショック蛋白質の発現がみとめられ, そのうち HSP70 の誘導量が最大であった. 非ストレス下では, 遠沈管培養軟骨細胞のうち肥大軟骨細胞様細胞への分化能を有すると考えられる細胞に HSP70 の発現が認められた骨端軟骨板においては, 肥大軟骨細胞で HSP70 が誘導されていた. また, HSP70 mRNA は肥大層に隣接する増殖層および静止層の軟骨細胞で観察された. このことは, 肥大軟骨細胞への分化能を有する軟骨細胞では, すでに HSP70 mRNA が誘導されていることを示している. これらの結果から, HSP70 の発現が軟骨細胞の分化と関係していることが推察された

A Neurophysiological Study on the Sympathetic Premotor Nuclei in the Pons and Medulla Oblongata

The aim of this study was to neurophysiologically demonstrate the activities of the premotor nuclei of sympathetic  vasomotion, by capturing the diachronic changes in the action potentials which are generated in  the pons and medulla oblongata. To do so, ten male Wistar rats weighing 300g were used as subjects.  Microelectrodes were inserted in the muscular branch of the sciatic nerve and the ventral side of the pons  and medulla oblongata, and the muscle sympathetic nerve activity (MSA) was induced. The regular spontaneous  action potentials, which synchronize with muscle sympathetic nerve activity, were observed in the  rostral ventrolateral medulla oblongata (RVLM), and the differences among the action potentials of individual  cells of the RVLM region noted. Autonomic postganglionic nerves are controlled in turn by preganglionic  nerves that originate from specific nuclei in the medulla. These nerves directly influence cardiovascular  function by regulating the rate and force of contraction of the heart and the diameter of blood  vessels. RVLM cells in fact exert a widespread control over the sympathetic outflow. We conclude from the  experiment that premotor nuclei of sympathetic vasomotion exist in the RVLM.

An Electrophysiological Experimental Study on the Spontaneous Sympathetic Nerve Activity in the Rostral Ventrolateral Medulla Oblongata

The sympathetic postganglionic nerve fibers, which are controlled by preganglionic fibers originating from  specific nuclei in the medulla oblongata, and the thoracic and upper lumbar segments of the spinal cord,  together with the local autoregulatory mechanisms and circulating hormones, directly influence the cardiovascular  function. Recently, the studies on the sympathetic preganglionic fibers have remarkably progressed,  and the anatomical (Strack et al., 1988), functional (Janig, 1985), and chemical (Krukoff, 1985)  characteristics of the synaptic input have been clarified. However, the peripheral sympathetic nerve activities  vary depending on the organs concerned (including the skin, muscle, or internal organs) as they have  their own physiological characteristics (Janig and McLachlan, 1986) including the response pattern to the  peripheral receptor stimulation. Many areas, including the histological and functional roles of the peripheral  part, nerve centers, and central pathway of the circulatory system, are still unknown. The peripheral sympathetic nerve activities in humans consist of the skin sympathetic activity (SSA) that  controls the sweat glands / skin vasomotion, and the muscle sympathetic activity (MSA) that controls the  vascular smooth muscles in the skeletal muscles, and each activity has different characteristics. SSA  involving regulation of the body temperature and MSA involving regulation of the blood pressure can be  separately recorded (Burke et al., 1977; Hagbarth et al., 1975; Vallbo et al., 1979; Wallin and Eckberg,  1982; Yatomi et al., 1989) from the sympathetic postganglionic efferent fibers by microneurography  (Hagbarth et al., 1972). By recording and comparing the action patterns and responses to stimulations of the premotor nuclei, along  with other vital rhythms, we hoped to clarify the complex mechanism of the sympathetic nerve activities  and to contribute in the treatment of disorders resulting from sympathetic dysfunction. We also report our  findings on the premotor nuclei that produce sympathetic preganglionic fiber activities by using topographic  mapping analysis of the changes in the central action potentials in the rostral ventrolateral medulla  oblongata (RVLM) region to visually capture the complicated action patterns to compare the cross correlations  with MSA and SSA using microneurography and ECG.

An experimental study on the peripheral autonomic nerve potential in the spinal cord injury model by microneurography

The purpose of the present investigation was to analyze the effects of spinal cord injury (SCI) on the  peripheral sympathetic nerve, skin sympathetic activity (SSA), and muscle sympathetic activity (MSA). To  do this sixteen male Japanese white rabbits weighing 1.0 kg-1.5 kg were used. The exposed spinal cord was  transected at various levels. Microelectrodes were placed on the muscular branch and on the cutaneous  branch, and they were separately induced using a 0.5 -5 kHz amplifier. The data were calculated with the  time reset integration value at 60 seconds. Results: It is usually satisfactory to considered that the peripheral sympathetic fibers from T1-3 generally  pass up through the sympathetic chain to the upper extremities, and that fibers from T9-11 pass up through  the sympathetic chain to the lower limbs. In the electrophysiological properties studied, the SSA could not  be recognized as a spontaneous activity. On the other hand, the MSA could be recognized as a spontaneous  regular activity which synchronizes with the R wave of the electrocardiogram. Conclusions: The MSA potentials synchronized with the heart rate, and they seem to correlate with the  body homeostasis. The existence of a central regulatory mechanism is suggested from those findings not  only in vital rhythms, such as the heart rate variability but also in the MSA.

A Case of Nonunion Avulsion Fracture of the Anterior Tibial Eminence

Avulsion fracture of the anterior tibial eminence is an uncommon injury. If bone union does not occur, knee extension will be limited by impingement of the avulsed fragment and knee instability will be induced by dysfunction of the anterior cruciate ligament (ACL). This report describes a 55-year-old woman who experienced an avulsion fracture of the right anterior tibial eminence during recreational skiing. Sixteen months later, she presented at our hospital with limitation of right knee extension. Plain radiography showed nonunion of the avulsion fracture region, and arthroscopy showed that the avulsed fragment impinged the femoral intercondylar notch during knee extension. The anterior region of the bony fragment was debrided arthroscopically until the knee could be extended completely. There was no subsequent instability, and the patient was able to climb a mountain 6 months after surgery. These findings indicate that arthroscopic debridement of an avulsed fragment for nonunion of an avulsion fracture of the anterior tibial eminence is a minimally invasive and effective treatment for middle-aged and elderly patients with a low level of sports activity

Analysis of heat shock proteins and cytokines expressed during early stages of osteoarthritis in a mouse model

SummaryObjective:Osteoarthritis (OA) is a debilitating disease of the joints. The joints of affected individuals are characterized by a progressive degeneration of articular cartilage leading to inflammation and pain. The expression of heat shock proteins (HSPs) is a ubiquitous self-protective mechanism of all cells under stress, furthermore, the synovium of osteoarthritic individuals contains high levels of cytokines. This study seeks to establish the role of HSPs and cytokines in OA.Methods:We have investigated the presence of HSPs and cytokines in articular cartilage during early stages of OA in a mouse that is known to develop spontaneous OA lesions (C57 black mouse). The articular cartilage from closely related mice (C57BL/6) was used as control. Messenger RNAs (mRNAs) for HSPs (HSP32, HSP47, HSP60, HSP70, HSP84 and HSP86) and cytokines [interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)] were detected by reverse transcription-polymerase chain reaction (RT-PCR).Results:The mRNA levels of HSP47, HSP70, HSP86, IL-6, and IFN-γ were up-regulated in the cartilage of C57 black mice, whereas, the level of expression of HSP32, HSP60, HSP84 and IL-1β remained unchanged. Furthermore, the expression of IL-1β, IL-6, TNF-α and IFN-γ mRNA was associated with expression of HSP60, HSP47, HSP70 and HSP70/HSP86 mRNA, respectively.Conclusions:The findings in this study suggest that chondrocytes are conditioned under non-physiological stress during early stages of OA, In addition, among HSPs, HSP70 was associated with two different highly expressed cytokines in C57 black mice, indicating the possible role of HSP70 as a characteristic indicator of early stage of OA

High Efficacy of Preoperative Low-Dose Radiotherapy with Sanazole (AK-2123) for Extraskeletal Ewing's Sarcoma: A Case Report

Extraskeletal Ewing's sarcoma is a rare soft tissue tumor that is morphologically indistinguishable from Ewing's sarcoma of bone. We report a case of extraskeletal Ewing's sarcoma with several systemic problems. A 69-year-old man presented with a 5-month history of a rapidly enlarging mass in the right thigh. Because preoperative radiotherapy with sanazole (AK-2123) contributed the tumor mass reduction down to 40% in size, the tumor was successfully resected with clear surgical margins and repaired with a musculocutaneous flap. The high efficacy of pre-operative low-dose radiotherapy with sanazole was histologically confirmed that the resected tumor specimen involved no viable tumor cells and showed 100% necrosis. Based on clinical outcomes in this case, the combined modality of pre-operative low-dose radiotherapy with hypoxic cell radiosensitizer and adequate surgical resection might provide for the useful clinical application of extraskeletal Ewing's sarcoma treatment