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G Murakami

Publications and source records attributed to G Murakami.

At least 37 records · Page 2Linked to original sources
PubMed2001

Ramification pattern and topographical relationship between the portal and hepatic veins in the left anatomical lobe of the human liver.

Sixty-one human livers obtained from donated Japanese adult cadavers were dissected to reveal the ramification pattern of the portal and hepatic veins, and their topographical relationship in the left anatomical lobe. The segmental portal vein supplying S2 (P2) tended to form a single stem, whereas that of S3 (P3) was usually double. An intermediate branch between P2 and P3 was observed in 23.0% of livers. In spite of variation between livers, definite P2 and P3 were identified in 47 specimens. One tributary of the left hepatic vein (LHV) was usually present for drainage of S2, and two tributaries were present for S3 (sometimes also for S2 and/or S4). The latter two tributaries of the LHV and the two subsegmental branches of S3 showed three patterns of three-dimensional interdigitations. From these results, the portal vein system did not seem to have a two segmental composition (i.e., S2 and S3) in 23.0% of specimens, whereas the hepatic vein system did not have an intersegmental course in 23.4%. Thus, there were obvious limitations in using each system to determine the liver segment. Taking the overlapping cases into consideration, the left anatomical lobe of 41.0% of specimens did not seem to fit the definition of Couinaud's liver segment. In addition, four patterns of fissure vein (or scissural vein), > 5 mm in diameter at its terminal, were identified: (1) middle hepatic vein type (left median vein, 9.8%); (2) LHV type (left medial vein, 41.0%); (3) true fissure vein (3.3%); and (4) absent cases (45.9%). The former two types also suggested limitations of the hepatic vein system as an indicator of the segmental border.

Adult↗
PubMed2001

[Configuration of the liver segment observed in the frontal section including the origin of the left portal trunk at the hepatic hilum].

After preparing threparing the frontal section including the origin of the left portal trunk at the hepatic hilum, 60 human livers (35, entirely; 25, partly) were dissected to reveal segmental configuration and the supplying portal vein branches. We usually observed two combinations of segments, i.e., S2, 4, 5 and 8 or S2, 3, 4, 5 and 8, in the frontal section including the origin of the left portal trunk. However, S8 was sometimes absent in the section when S4 extended to the right and/or upper side. S2 was consistently located dorsal to S3 despite the fact that 11.7% of the specimens carried an unexpected configuration showing a "lower" S2 in combined with an "upper" S3 in the frontal section. The latter case was associated with specific S2 and S3 segmental branches maintaining horizontal courses along a common plane. S4, S5 and S8 were usually arranged from the ventral to the dorsal aspect in this order. Four types of ventral short branches originated at or near the primary portal divisions and supplied the hilar parenchyme adjacent to S4 and/or the anterior segment (S5 or S8). These ventral short branches tended to be associated with the variations of the primary division. Dissection of the liver after frontal section provided a better understanding of the segmental configuration rather than an approach from the hepatic hilum.

Aged↗
PubMed2000

Genetic defect in human X-linked agammaglobulinemia impedes a maturational evolution of pro-B cells into a later stage of pre-B cells in the B-cell differentiation pathway.

Surrogate light chains (lambda 5/VpreB) are selectively expressed in early precursors of B cells. B-cell defects in X-linked agammaglobulinemia (XLA) are caused by mutations in the gene for Bruton's tyrosine kinase. To elucidate the nature of early B-lineage cells in bone marrow (BM), samples from 13 XLA patients and 24 healthy controls of different ages were comparatively analyzed using an antihuman VpreB monoclonal antibody. Expression of surrogate light (SL) and mu-heavy chains were examined after cell membrane permeabilization because they are mainly expressed in the cytoplasm of early B-lineage cells. A flow cytometric analysis of normal BM identified 5 discrete cell types of B cells: mu(-)SL(++) (pro-B [B-cell progenitor]), mu(low)SL(++) (pre-B1a), mu(low)SL(+) (pre-B1b), mu(low)SL(- )(pre-B2), and mu(high)SL(- )(B). The large cells, presumably in cycling states, were enriched in pre-B1a cells. The frequencies of B-lineage cells in BM were higher in young children, and declined with advancing age. In contrast, XLA showed a profound reduction in BM B-lineage cells. In XLA BM, an expansion of pro-B cells with some small pre-B1a cells was marked, but other cells were negligible. These observations illustrate a B-cell maturation defect in XLA as well as a normal human B-cell differentiation pathway. The results suggest that the genetic defect in XLA may impede the evolution of pro-B cells beyond the earlier pre-B stage into the later stage of pre-B cells in B-cell development. (Blood. 2000;96:610-617)

Adolescent↗
PubMed2000

Morphometric study of the sphincter of oddi (hepatopancreatic) and configuration of the submucosal portion of the sphincteric muscle mass.

The sphincter of Oddi (SO) hepatopancreatic sphincter from 114 Japanese adults, especially the sphincteric muscle mass lying in the duodenal mucosal layer (the submucosal portion of the SO: SMSO), was measured macroscopically under a binocular microscope. The SMSO was classified into two types according to shape. The horizontal type (95/114) usually displayed a rod-like shape (6.0 mm at average diameter at the root) directed toward the anus and was situated on the duodenal muscle wall with the papillary orifice at or near the tip (anal side) of the SMSO. The horizontal type SMSO followed the underlying muscle wall widely ranging from 5.0 mm to 17.9 mm length (9.8 mm at average) and was attached to the wall by the loose connective tissue along the entire length. In the horizontal type, the extramural portion (the portion penetrating and outside of duodenal muscle of the SO) of the SO was very small. The vertical type (19/114) erected on the muscle wall vertically into the lumen of the duodenum. The average length and average maximum diameter of the vertical type were 6.0 mm and 6.2 mm, respectively. The extramural portion of the SO was thicker and tighter in the vertical type, which suggested that endoscopic sphincterotomy might preserve the length of the SO longer than endoscopic papillary balloon dilation (EPBD). Of the individuals in our study, 18% (19/114) had SO diameters <5 mm, a finding that may have implications for selection of balloon size in EPBD.

Aged↗
PubMed2000

Topographical relationships among the facial nerve, chorda tympani nerve and round window with special reference to the approach route for cochlear implant surgery.

The topographical relationships among the facial nerve (FN), chorda tympani nerve (CT), and round window (RW) in 22 temporal bone specimens were analyzed morphometrically in order to examine which route is widest through the facial recess between the FN and CT during cochlear implant surgery and in order to establish some criteria to assist in the evaluation of the best surgical approach. Two lines, i.e., the FN-RW line and CT-RW line, were speculated as limitations of a visual field for this surgery. According to the relative position of these structures, including the posterior wall of the external auditory canal (EAC) and an inserted pin-gage that indicates the hypothetical widest approach route, the relationships were classified into five types. Most frequently, the widest approach route through the facial recess did not point directly at the RW, but at the basal turn at the promontory. Moreover, this approach route crossed the FN-RW line in a posterior to anterior direction and the CT-RW line frequently crossed the posterior wall of the EAC. The latter seemed to provide a critical landmark for avoiding damage to the CT during cochlear implant surgery. Therefore, we recommend inserting the electrode into the basal turn.

Adolescent↗
PubMed2000

Posterior pulmonary lobe: segmental and vascular anatomy in human specimens.

The posterior pulmonary lobe (PPL) is defined by an aberrant fissure running horizontally on the costal surface of the lower lobe. We studied the frequency of the PPL, and the ramification of bronchi and vessels in the PPL, and so describe mainly these differences compared to the normal lung. Nineteen PPL cases (15 right and 4 left) were found in 273 (116 right and 157 left) human lung specimens. The incidence of PPL was 13% on the right side and 3% on the left side. The PPL frequently (right 87%, left 50%) corresponded to S(6) (superior segment). Analysis of the ramification of bronchi revealed that B(7) (medial basal bronchus) tended to form a common trunk with B* (subsuperior bronchus) or B(8) (anterior basal bronchus). Analysis of the ramification of veins revealed that V(6) (superior vein) tributaries were often double, and V(6) tended to disperse widely. Anomalies in which the segmental artery and vein communicated with other segments were found in seven cases (37%) (4 arteries and 3 veins, 6 right and 1 left) in PPL. These results show that the PPL does not always correspond to S(6) and frequently has an anomalous vessel from other segments. This is valuable surgical information, particularly in S(6) segmentectomy.

Bronchi↗
PubMed2000

Configuration of the right portion of the caudate lobe with special reference to identification of its right margin.

The configuration of the right portion of the caudate lobe (CL), and especially the exact location of its right margin, remains obscure. This study aimed to identify this right margin according to reliable landmarks suitable for use during clinical examinations and surgery: (1) the bifurcation of the right portal vein, (2) the end of the right hepatic vein, and (3) the notch on the gallbladder fossa. The plane defined by these three landmarks is called the right paracaval plane. Dissection of 55 livers demonstrated that the entire CL was usually contained within the left half of the specimen after cutting along the right paracaval plane (Type A: 65.4%, 36/55). However, its right portion sometimes extended beyond this plane into the right half of the liver (34.6%, 19/55), forming one or two islands when viewed from the paracaval plane (Types B and C). We found two separate marginal configurations among the 19 rightward extensions of the paracaval portion: a tree-like, deep protrusion (11/19) and a relatively smooth border (8/19). The present results suggest the existence of reliable landmarks that will allow a right-side limit for surgical resection of the CL to be established: (1) the right paracaval plane (60% reliability), (2) 10 mm to the right of the plane, including the terminal of the right hepatic vein (80% reliability), and (3) the widest margin, including the 30 mm to the right of the right paracaval plane, the right side running along the inferior vena cava, and the diaphragmatic surface around the end portions of the three main hepatic veins (100% reliability).

Aged↗
PubMed2000

Morphometric study of the medial aspect of the human maxillary sinus with special reference to the nasal fontanelle.

OBJECTIVE: The purpose of this study was to clarify configurations of the nasal fontanelle (NF) from the morphometrical point of view, especially variations of its four margins (anterior, posterior, superior, and inferior), for clinical application. METHODS: We used 136 sides of hemi-sectioned heads that were obtained from 119 donated Japanese cadavers (66 men and 53 women with an average age of 77.6+/-12.0). After mucosal examination, the specimens were boiled with a small amount of powdered soap and treated with protease. The residual mucous membrane was then gently removed. These specimens were originally made for our previous study describing variations of the uncinate process (Isobe M, Murakami G, Kataura A. Variations of the uncinate process of the lateral nasal wall with clinical implications, Clin. Anat. 1998;11:295-303). Different series of measurements were conducted based on surgical approaches and angles of observation. RESULTS: The superior margin of the NF is difficult to identify because the ethmoidal infundibulum, which leads the anterior end of the margin upward, often interrupts the superior margin. Because the inferior and posterior margins are modified by thin paper-like bony structures and because the anterior margin is disturbed by variations of the lacrimal bone and/or the inferior turbinate, they are also difficult to identify. Knowing these variables, we evaluated the NF morphometrically. The NF was located 12.6+/-4.3 mm posterior to the anterior nasal spine and 6.6+/-2.2 mm anterior to the sphenopalatine foramen. The size of the NF was 17.9+/-3.2 mm (anteroposterior axis) x 11.5+/-3.0 mm (inferosuperior axis). The lowest orbital floor was located 10 mm below the superior margin of the anterior NF (-10 mm), and the distance was therefore measured as -3.7+/-2.4 mm on average. Viewed from the maxillary sinus, the location of the NF varied along the anteroposterior axis, whereas it was located consistently at the most superior portion of the medial aspect of the sinus wall. CONCLUSION: During endoscopic sinus surgery for tumor resection in the maxillary sinus, a large and primary window should be prepared in the posterior NF, including partial removal of the uncinate process. Preparation of an additional window in the inferior meatus is preferable to enlargement of the primary window. Approaching the anterior NF should be avoided, if possible, due to its complicated configuration as well as its proximity to the orbital floor.

Aged↗
PubMed2000

Supraclavicular artery in Japanese: an anatomical basis for the flap using a pedicle containing a cervical, non-perforating cutaneous branch of the superficial cervical artery.

We investigated the morphology of the non-perforating cervical cutaneous branch in the lateral cervical triangle using 65 (130 sides) donated cadavers. We found the branch in 104 of the entire 130 sides (80.0%). In the majority (72.1%), the cutaneous branch did not cross the clavicle or acromion but supplied the dorsolateral cervical area. The branch was originated from the superficial cervical artery close to the posterior belly of the omohyoideus muscle and immediately lateral to the external jugular vein. The comitant vein, if present, drained into the external jugular vein. Our observations and measurements (length and diameter) suggested that the non-perforating cutaneous branch is useful for a pedicle of the dorsolateral cervical flap in Japanese people. However, detailed morphologies differ from the previous studies published in western countries.

Aged↗
PubMed2000

[A case of congenital cystic adenomatoid malformation of the lung in a 4-year-old child].

A case of congenital cystic adenomatoid malformation (CCAM) of the lung is reported. A 3-year-old boy was admitted for elevation of infiltrative shadow in the right lower lung field on a chest X-ray. The clinical diagnosis was emphysematous bullae with inflammation. After 6 months, he had recurrent infected bullae, and was admitted. He received chemotherapy with antibiotics prior to the operation. Right lower lobectomy was performed on February 2, 1998. The resected lung was composed of multiple cysts with thin wall measuring 10-60 mm in diameter. The histological examination of specimen revealed CCAM (Stocker type I), which is rare in this age. The patient has been well for 16 months postoperatively.

Child, Preschool↗
PubMed2000

Hepatic grooves and portal segmentation.

The aim of the present study was to examine the topographical relationship between the locations of the grooves and the borders of Couinaud's portal segments. We found 79 grooves on the diaphragmatic surfaces of 50 livers from 420 cadavers. Most grooves were located within segment VIII wholly (31/79) or partially (39/79). By contrast, only 11 grooves corresponded to the border between two segments (segments VIII/IV in 6 cases and segments VIII/VII in 5 cases). Diaphragmatic indentations (fold-like protrusions) into the groove were observed in 1 case. Our results suggest that the grooves did not form during the early embryonic period when intrahepatic vessels and ducts ramify, but that they formed during a later stage of diaphragmatic growth after establishment of the basic segmental configuration of the liver. The grooves do not seem to be critical landmarks for segmental borders of the liver.

Aged↗
PubMed2000

[Insect allergy].

Explore the source record for details and available documents.

Allergens↗
PubMed1999

First dorsal interosseous muscle of the foot and its innervation.

During dissection of the foot region, it is frequently found that some nerve branches run close to the tibial surface of the second metatarsal bone. To investigate the nerve branches, detailed dissection of the first dorsal interosseous muscle was performed in 10 Japanese adult feet with special reference to its innervation. In all specimens the muscle was clearly separated into lateral and medial parts. The branches ran between these parts and innervated the parts. The small dorsal region of the medial part of the muscle was also innervated by a branch of the deep peroneal nerve. Based on its innervation, the muscle appears to be composed of two elements from the flexores breves profundi and an element from the dorsal primordium. A possible schematic model of the origins of this muscle is proposed.

Adult↗
PubMed1999

Identification of segments VI and VII of the liver based on the ramification patterns of the intrahepatic portal and hepatic veins.

We describe the pattern of intrahepatic vessel ramification in the right posterior hepatic sector in a population of 197 adults. Each specimen was dissected from its visceral (inferior) surface in order to demonstrate variations in the distribution of the portal vein branches to the hepatic segments of the right lobe, especially to segments VI (S6) and VII (S7) as described by Couinaud. We also examine whether three hepatic veins, i.e., the right hepatic vein (RHV), middle hepatic vein (MHV), and the short hepatic vein (SHV), aid the identification of segmental portal branches in the lower posterior sector. Four major patterns of branching of the posterior sectorial trunk of the portal vein system are described. In group A (32.0%) a single posterior trunk formed an arch-like pattern sending multiple branches to S6 and S7 (P6 and P7). We named the multiple branches to the apparent S6 the inferoposterior portal branches. It was difficult to identify which of these branches were equivalent to P6. In group B (27.9%), the posterior sectorial trunk bifurcated to form P6 and P7. In most of the specimens in this group, therefore, we were able clearly to identify both S6 and S7 based on the portal vein system. In group C (6.6%), the trunk trifurcated to form P6, P7, and an intermediate branch, which supplied both segments or a gray zone between them. Group D (33.5%) included variations of the anterior segmental branches, and in specimens of this group, the anteromedial border of the sector was difficult to identify. Notably, the three-dimensional interdigitating topographical relationship of the hepatic veins and the portal branches was not evident in the lower posterior sector, since tributaries of the RHV and the portal branches followed similar courses and paralleled each other in the region and since the territory of the SHV was usually restricted to the superficial parenchyma near the inferior surface. In group A, tributaries of the RHV/SHV (>3 mm in diameter) passed between the inferoposterior portal branches in only 22.2%/14.3% of the specimens. Thus the hepatic veins often did not reveal which of the multiple inferoposterior branches was P6. Moreover, in the subset of Group B in which the segments were identified based on the portal vein ramification, tributaries of the RHV/SHV (>3 mm in diameter) showed the intersegmental interdigitating arrangement in only 32.0%/6.0% of the specimens. In addition, a thick tributary of the MHV, sometimes arising from S6, did not run along, but penetrated the S5/S6 border plane from the lateral to the medial side. Therefore, the three hepatic veins (RHV, SHV, MHV) often did not aid the identification of the liver segments in the region. Consequently, the less than ideal combinations of irregular configurations of the portal and hepatic venous systems suggest that the right posterior segments cannot be conclusively identified anatomically in 30-40% of cases. Other means of identification, such as the conventional proportional manner (the upper and lower halves of the posterior sector roughly correspond to S6 and S7) may be required.

Adult↗
PubMed1999

Vascular anatomy of the pancreaticoduodenal region: A review.

Vascular anatomy of the pancreaticoduodenal region has been the subject of numerous studies. However, several essential areas of confusion remain in interpretation of the vascular configuration. We note and discuss three key points in relation to this confusion: (1) a missing vascular arcade, (2) a rearrangement of the arcade by collateral and/or transverse vessels, and (3) a solitary vessel without an accompanying comites vein or artery. In addition, we consider that different interpretations as well as varying reported incidences depend on different "thresholds" when observations are made. Consideration of new aspects of vascular anatomy of the pancreaticoduodenal region is required for further improvement of surgical procedures. In terms of the selection of lymph node resection procedure, we discuss mainly the inferior arterial origin. Special attention should be paid to the ligation of inferior arteries because of the high incidence of the common trunk formation of the upper jejunal and inferior pancreaticoduodenal arteries. With regard to duodenum-preserving pancreatic head resection for benign tumors, our observations are introduced in view of either arterial or venous configuration. First, a communicating artery between the anterior and posterior arterial arcades is noted because of its possible critical role in blood supply to the papilla of Vater. Second, a venous drainage route from the duodenum to the retroperitoneal space in "normal" specimens is described.

Dissection↗
PubMed1999

Cartilage degeneration in talocrural and talocalcaneal joints from Japanese cadaveric donors.

In a study human cadavers, degenerative change (DC) was observed more frequently on articular surfaces of the talocrural joint (55. 8%) than on the articular surfaces of the talocalcaneal joint (29. 5%). In the talocrural joint, the anteromedial segments of the tibial plafond, talar dome, and the medial malleolar facet exhibited a high frequency of DC. Moreover, most DCs were found to coexist in multiple segments that often included both the tibial and talar sides. In the talocalcaneal joint, by contrast, DC tended to be distributed diffusely over the articular surfaces. If the DC occurred initially and progressed to a cartilage defect, it tended to be restricted to a certain portion of the talocalcaneal joint. Mirror-image lesions were observed much less frequently than expected in both the talocrural (28.3%) and talocalcaneal joint (25. 0%). Notably, these lesions were not usually observed even if the DC had progressed to a cartilage defect. We considered that the DC tended to advance to the adjacent segment on the same side rather than to the complementary segment on the opposite side. We demonstrated that the more multiple DC lesions were present in the talocrural joint, the more often DC occurred in the talocalcaneal joint. Consequently, we believe than multiplicity of DCs is more critical for the downward joint-to-joint progression of DC than is increased severity.

Adult↗
PubMed1999

Does the Adamkiewicz artery originate from the larger segmental arteries?

OBJECTIVE: The Adamkiewicz artery supplies most of the blood to the anterior spinal artery, which perfuses the anterior two thirds of the spinal cord. During operations for thoracoabdominal aortic aneurysm, detailed anatomic knowledge of the Adamkiewicz artery and its correlation with the intercostal and/or lumbar arteries is important to prevent postoperative paraplegia. METHODS: Minute dissection was performed on 102 formol-fixed adult cadavers without any history of circulatory disorders. The Adamkiewicz artery was found in the epidural space after laminectomy of the vertebrae. The entire course between the Adamkiewicz artery and the intercostal and/or lumbar artery was dissected carefully. The vertebral level, laterality, and mean diameter of all Adamkiewicz arteries were investigated. The correlation between the diameter of the Adamkiewicz artery and that of the intercostal and/or lumbar arteries was also determined. RESULTS: The mean number of Adamkiewicz arteries per cadaver was 1.3 +/- 0.65, and the mean diameter was 0.77 +/- 0.24 mm (range, 0.50 to 1.49 mm). Approximately 70% of the Adamkiewicz arteries originated from the intercostal and/or lumbar arteries on the left side, frequently at the T8-L1 vertebral level. There was no statistically significant correlation between the diameter of the Adamkiewicz artery and that of intercostal and/or lumbar arteries. CONCLUSION: This study provides evidence that, during operations on the thoracoabdominal aorta, the intercostal and/or lumbar arteries should be preserved, regardless of their diameter, to prevent postoperative paraplegia.

Adult↗