[show abstract][hide abstract] ABSTRACT: We investigated forty-five head halves of 25 Japanese cadavers in order to obtain precise anatomical knowledge of the courses and distribution of the branches of the mandibular nerve positionally related to the lateral pterygoid muscle. After complete removal of the bony elements, several patterns of the positional relationships between the lateral pterygoid and surrounding nerves were noted. The lateral pterygoid is innervated by branches of the anterior and middle deep temporal nerves, the main trunk of the mandibular nerve and the auriculotemporal nerve, and by branches originating from the forks of these nerves. In two specimens, the buccal nerve was composed of the root from the common trunk with the anterior deep temporal nerve and the root of the middle deep temporal nerve. Based on the positional relationships between the masticatory muscles and the branches of the mandibular nerve, the lateral pterygoid is located in the center of the muscles. Variations in the nerve routes related to the lateral pterygoid are considered to reflect the variability of the differentiation patterns of the anlage of the muscle.
European Journal of anatomy, ISSN 1136-4890, Vol. 7, Nº. 1, 2003 (Ejemplar dedicado a: Supplement 1.), pags. 5-14. 01/2012;
[show abstract][hide abstract] ABSTRACT: We dissected 50 head halves of 25 Japanese cadavers (10 males, 15 females) to investigate the innervations of the levator veli palatini (LVP) and superior constrictor pharyngis. The branches supplying the LVP were classified into the following three types according to their origins: supplying branches that originated from the pharyngeal branch of the glossopharyngeal nerve (type I, four sides, 8%), branches that originated from a communicating branch between the pharyngeal branches of the glossopharyngeal and vagus nerves (type II, 36 sides, 72%), and those that originated from the pharyngeal branch of the vagus nerve (type III, 10 sides, 20%). In previous studies, supplying branches of type I were seldom described. Regarding the innervation of the superior constrictor, some variations were observed, and we consider it likely that there is a close relationship between these variations and the type of innervation of the LVP.
Surgical and Radiologic Anatomy 05/2004; 26(2):100-5. · 1.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: The c-Mpl, thrombopoietin (TPO) receptor specificially controls megakaryocytic growth and differentiation. TPO increased the c-mpl promoter activity determined by a transient expression system using a vector containing the luciferase gene as a reporter in the human megakaryoblastic cell line CMK. The maximal promoter activity of c-mpl was obtained 24 hr after pretreatment with TPO for 3 hr and then declined with time. This increase was completely abolished by protein kinase C (PKC) inhibitors (GF109203, calphostin C and H7). Phorbol 12-myristate 13-acetate (PMA) treatment led to an increase in c-mpl promoter activity. These results demonstrate that the promoter activity of c-mpl is modulated by transcription through a PKC-dependent pathway.
[show abstract][hide abstract] ABSTRACT: The striated sphincter of the male urethra, the so-called rhabdosphincter, contributes significantly to urethral closure pressure. It is generally agreed that the somatic nerve fibers from the pudendal nerve innervate the rhabdosphincter, and the autonomic nerve fibers innervate the smooth muscle of the urethra. Although it is difficult to clearly identify the rhabdosphincter macroscopically, we minutely investigated the nerve branches to the urethral sphincter muscle region in 10 male pelvic halves. In addition, the origins and courses of the pudendal plexus in 88 male pelvic halves were investigated. To this region were given branches of the pudendal nerve and the pelvic plexus. The branches from the pelvic plexus to the region generally originated from S4 as the lowest branch of the pelvic splanchnic nerve, and ran along the rectal attachment of the levator ani. The caudal root of the pelvic splanchnic nerve formed a common trunk with the nerve to the levator ani (94%). Various connections were sometimes observed between the pudendal nerve and the branches medial to the levator ani. It is suggested that the somatic nerve fibers from the nerve to the levator ani or from the pudendal nerve might also join the nerve branches to the region from the pelvic plexus.
Surgical and Radiologic Anatomy 01/2003; 25(5-6):387-92. · 1.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: The aim of this study was to improve surgical techniques for arthroscopically-assisted anterior cruciate ligament (ACL) reconstruction with minimal sensory disturbance in the infrapatellar and anterior lower leg regions. Thirteen patients with sensory disturbance were examined neurologically, and 51 lower limbs of 26 adult cadavers were examined anatomically to investigate the nerve branches supplying the regions. The region of sensory disturbance was supplied by branches of the medial femoral cutaneous nerve and the saphenous nerve, and the nerves showed a complementary distribution area. After detailed investigation of the positional relationships between the nerve branches and the skin incisions of the operative procedure, it was found that at least one branch of both nerves ran across the longitudinal skin incision (80%) for tendon harvest in the above-mentioned reconstruction. The complicated anatomic variations of the nerve branches preclude their absolute avoidance in any surgical incision, and a completely safe zone could not be found in the present study. However, an oblique incision for the tendon harvest rather than the typical longitudinal incision should be considered to minimize the sensory disturbance.
Surgical and Radiologic Anatomy 01/2003; 25(3-4):192-9. · 1.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: A nervous branch which passes through a small canal in the sphenozygomatic suture is sometimes observed during dissection. To examine the origin, course and distribution of this nervous branch, 42 head halves of 21 Japanese cadavers (11 males, 10 females) and 142 head halves of 71 human dry skulls were used. The branch was observed in seven sides (16.7%); it originated from the communication between the lacrimal nerve and the zygomaticotemporal branch of the zygomatic nerve or from the trunk of the zygomatic nerve. In two head halves (4.8%), the branch pierced the anterior part of the temporalis muscle during its course to the skin of the anterior part of the temple. The small canal in the suture was observed in 31 head halves (21.8%) of the dry skulls. Although this nervous branch is inconstantly observed, it should be called the temporal branch of the zygomatic nerve according to the constant positional relationship to the sphenoid and zygomatic bones. According to its origin, course and distribution, this nervous branch may be considered to be influential in zygomatic and retro-orbital pain due to entrapment and tension from the temporalis muscle and/or the narrow bony canal. The French version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00276-002-0027-4.
Surgical and Radiologic Anatomy 06/2002; 24(2):113-6. · 1.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: The superfine flip-chip interconnection was evaluated on the chip on chip (COC) structure with the daisy chain patterns. The electroplated Au bumps allocated on the periphery of the Si chip in 20μm-pitch were applied to the experiments. The underfill resin incorporated with the hyperfine filler particles achieved the acceptable reliability in the temperature cycling test (TCT) of the micro joints. The results showed no failure over 1,000 cycles with the optimized underfill resin. The finite element method (FEM) analysis found that the hyperfine filler particles in the underfill resin could reduce the equivalent plastic strain of micro-Au-bumps less than 1.0%, especially concentrated around the center of the interconnection at the bonding interface during TCT. In addition, the results in TCT with the optimized underfill resin were superior to the results with no underfill resin even as the results on COC structure. In case of the result with no underfill, it was found that the breakage occurred in the different mode as the results with the underfill resin, which was supposed from the dissimilar distribution of the strain due to the difference of the coefficient of thermal expansion (CTE) between the Au bumps and the Si devices.
Electronic Components and Technology Conference, 2002. Proceedings. 52nd; 02/2002
[show abstract][hide abstract] ABSTRACT: Mechanical effects of copper through-vias formed in silicon dies in a three dimensional module, in which four bare-dies with copper through-vias are vertically stacked and electrically connected through the copper-vias and metal bumps, were numerically and experimentally studied. To examine the mechanical effects caused by the existence of the copper through-vias in a rigid silicon-chip, a series of stress analyses, related simple mechanical tests, and reliability tests were carried out. All these results show that the copper through-via has unique effects on the stress distribution caused by thermal mismatch and on the interconnection reliability in the 3D die-stacked module. In particular, it was found that the developed micro copper through-via is reliable because the stress distribution due to thermal load is close to the hydrostatic pressure condition, and enhances chip-to-chip interconnection reliability because the copper-via restrains the plastic deformation of a gold bump during temperature cycling.
Electronic Components and Technology Conference, 2002. Proceedings. 52nd; 02/2002
[show abstract][hide abstract] ABSTRACT: It is reported that the stay in the space develops anemia, thrombocytopenia, and altered function and structure of red blood cell. The mechanism of these abnormalities was not clarified yet. The cloning of the thrombopoietin (TPO), followed by the analysis of TPO and c-mpl (its cellular receptor) knockout mice confirmed its role as the primary regulator of thrombopoiesis. TPO has been shown to stimulate both megakaryocyte colony growth from marrow progenitor cells and the maturation of immature megakaryocyte to form functional platelet. This process includes the massive cytoskeletal rearrangement, such as proplatelet formation and fragmentation of proplatelet. In this study we have focused on the production of thrombopoietic growth factors in mice those were exposed to gravity change by parabolic flight (PF).
Biological Sciences in Space 11/2001; 15(3):302-3.
[show abstract][hide abstract] ABSTRACT: Form deprivation myopia in chicks is a widely accepted model to study visually-regulated postnatal ocular growth. The chick sclera has a cartilaginous layer as well as the fibrous layer found in mammals. It appears that a dynamic relationship exists between these two layers during visual deprivation-induced growth. The changes in the fibrous sclera of myopic eyes, however, have not been previously described. This investigation is focused on the comparative morphological analyses of the cartilaginous and fibrous scleral changes in myopic chick eyes. The fibrous scleral changes in the posterior segment of myopic eyes were examined in detail using light and electron microscopy, and the expression of growth factors was analysed by immunohistochemistry. In the posterior segment of myopic eyes the border between the cartilaginous and fibrous layers was indistinct because of collagen bundles of the fibrous sclera that spread into the cartilaginous sclera, whereas in control eyes the distinction was clear. Various types of transitional cells, from fibroblast-like mesenchymal cells to chondrocytes, were found in the border between the cartilaginous and fibrous layers. Collagen fibrillar diameters of the fibrous sclera in the posterior segment of myopic eyes were smaller than in control, whereas those in the equatorial segment were almost the same in myopic and control eyes although the distribution of sizes was obviously different. Thus, changes in the fibrous sclera in myopic eyes of chicks seem to be similar to scleral changes in myopic eyes of mammals. The cells in the posterior sclera of myopic eyes were more intensely immunostained for TGF-beta and IGF-II than control, whereas no immunoreaction of TGF-alpha could be detected in either control or myopic eyes. These results suggest that the structural characteristics of the posterior sclera are different from those of the anterior and equatorial segments. Undifferentiated mesenchymal cells might be concentrically distributed exclusively in the innermost layer of posterior fibrous sclera. TGF-beta and IGF-II might influence cell growth, differentiation, and migration in the exaggerated scleral growth accompanying myopia.
Experimental Eye Research 11/2001; 73(4):533-46. · 3.03 Impact Factor
[show abstract][hide abstract] ABSTRACT: The patient was a 46-year-old man with a history of syncope attack after diarrhea. Nonsustained polymorphic ventricular tachycardia (PVT) initiated by short-coupled premature ventricular complex was detected by Holter monitoring. No organic heart disease was found, and the QT interval during sinus rhythm was normal. It was thought that the PVT might be related to hypokalemia, so electrophysiological studies were performed under the condition of hypokalemia (K=3.4mmol/L), after potassium loading (K=4.2mmol/L) and after oral amiodarone therapy. Under the condition of hypokalemia, nonsustained PVT occurred spontaneously, and the monophasic action potential duration at 90% repolarization (MAPD90) at the right ventricular apex was very short (175 ms). The MAPD90 returned to normal after loading potassium (230ms) and after oral amiodarone therapy (240ms), and PVT no longer occurred. With continued oral amiodarone and spironolactone therapy, the patient has been free of syncope attack over a follow-up period of 5 years.
Japanese Circulation Journal 09/2001; 65(8):757-60.
[show abstract][hide abstract] ABSTRACT: Apoptosis in regressive primary (deciduous) dental primordia was examined in the embryos of Suncus murinus, which is a monophyodont. The primary tooth germs of S. murinus are temporarily formed and disappear during the embryonic period before they are calcified. Most primary tooth germs reach the bell stage and degenerate by embryonic day 22 (E22). Light microscopy on haematoxylin-eosin-stained sections revealed that intensely labelled granular substances are frequently present in the epithelial portion (enamel organs) of the deciduous tooth germs during the period from E18 to E20. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labelling method, computer-assisted three-dimensional reconstructions, and electron microscopy confirmed that these variable-sized granular substances are similar to apoptotic cells or bodies. Apoptotic structures were mainly found in the primary tooth germ located on the buccal surface of the secondary (successional) tooth germ. These results lead to the conclusion that apoptosis is closely associated with the involution and disappearance of the deciduous tooth germ in S. murinus. A primary tooth germ was observed on the buccal side of all the corresponding successional tooth germs, although the buccal surface of the secondary tooth germ of third upper molar teeth developed only to epithelial thickening without mesenchymal condensation. The findings, therefore, suggest that apoptosis is responsible for disappearance of the primary dental primordia during tooth development in S. murinus.
Archives of Oral Biology 08/2001; 46(7):649-60. · 1.55 Impact Factor
[show abstract][hide abstract] ABSTRACT: This paper reports the quantitative evaluation of the H-reflex exhibited by parabolic flight with exposure to micro and high-gravity. With respect to previous findings in parabolic flights and short-term space missions, the analysis focused on reflex activity in weightlessness. The aim of this study was to investigate the effect of gravity on H-reflex and motor evoked potentials (MEP) in soleus muscle (SOL) during parabolic flight.
Journal of gravitational physiology: a journal of the International Society for Gravitational Physiology 08/2001; 8(1):P97-9.
[show abstract][hide abstract] ABSTRACT: It is reported that the stay in the space develops anemia, thrombocytopenia, and altered function and structure of red blood cell. The mechanism of these abnormalities was not clarified yet. Therefore, it is necessary to elucidate the mechanism of the effect of the gravity change on the thrombocytopoiesis, which plays the important role for the hemostasis, using animal models. The cloning of thrombopoietin (TPO), followed by the analysis of TPO and c-mpl (its cellular receptor) knockout mice confirmed its role as the primary regulator of thrombopoiesis. TPO has been shown to stimulate both megakaryocyte colony growth from marrow progenitor cells and the maturation of immature megakaryocyte to form functional platelet. This process includes the massive cytoskeletal rearrangement, such as proplatelet formation and fragmentation of proplatelet. In this study we have focused on the thrombopoiesis in mice those were exposed to gravity change by parabolic flight (PF).
Journal of gravitational physiology: a journal of the International Society for Gravitational Physiology 08/2001; 8(1):P63-4.
[show abstract][hide abstract] ABSTRACT: During examination of the positional relationships between the lateral pterygoid and the temporalis muscles and the innervating nerves, an aberrant muscle was observed in three of 66 head halves. The aberrant muscle originated from the medial surface of the anteromedial muscle bundle of the temporalis (Shimokawa et al. 1998, Surg. Radiol. Anat. 20:329-334) and inserted into the inferolateral surface of the lower head of the lateral pterygoid. Due to its location, origin and insertion this aberrant muscle slip is considered to correspond to the pterygoideus proprius described by Henle (1858, Handbuch der Anatomie des Menschen). Based on the innervation findings, the present aberrant muscle might be considered as a remnant muscle bundle between the anteromedial muscle bundle of the temporalis and the lateral pterygoid during differentiation of the lateral masticatory muscle anlage.
[show abstract][hide abstract] ABSTRACT: It has been well known that balance instabilities after long-term exposure to microgravity (e.g., Anderson et al. 1986) or bedrest (BR) can be related to alterations and/or adaptations to postural control strategies. Little is known, however, how the reduced muscular activity affects the activation pattern of the lower limb muscles during quiet standing (QS). The purpose of this study was to investigate whether or not any changes in the lower limb muscle activation patterns during QS would occur after BR.
Journal of gravitational physiology: a journal of the International Society for Gravitational Physiology 08/2001; 8(1):P85-6.