Biomedical subjects

M Shimada

Publications and source records attributed to M Shimada.

At least 541 records · Page 30Linked to original sources

PubMed1994

Characteristics of hepatocellular carcinoma originating in the caudate lobe.

Nine patients with hepatocellular carcinoma originating in the caudate lobe who underwent hepatic resection were studied. The caudate lobe was divided into three parts, according to the criteria of Kumon, including the Spiegel lobe, the paracaval portion and the caudate process. The tumors were located in the Spiegel lobe in four, the paracaval portion in four and the caudate process in one. Surgical procedures consisted of right hepatic lobectomy in one, central bisegmentectomy in one and caudate lobectomy in seven. The mean surgical time was 379 +/- 129 min; the mean estimated blood loss was 2,994 +/- 2,303 ml. The above-mentioned surgical risks were more clearly recognized in the paracaval portion than in the Spiegel lobe. In addition, most patients experienced significant post-operative complications. Six of eight patients with 6 mo or longer follow-up had recurrences, and two of six patients died. The characteristics of hepatocellular carcinoma in the caudate lobe were as follows: (a) a higher surgical risk, and more definite risk in the paracaval portion; and (b) a higher rate of early recurrence. A left lobectomy for the Spiegel lobe, a right or left trisegmentectomy for the paracaval portion and a right lobectomy for the caudate process would be ideal from the point of view of the portal supply of the caudate lobe. However, in cirrhotic patients either a caudate lobectomy or partial resection might be preferable because longer survival can be expected.

Aged↗

PubMed1994

Xanthogranulomatous cholecystitis masquerading as gallbladder carcinoma.

We herein present a case of xanthogranulomatous cholecystitis which involved both the liver and transverse colon, clinically mimicking gallbladder carcinoma. Such cases may sometimes be judged inoperable due to extensive extra-gallbladder invasion, and thus it is necessary for physicians to take this lesion into consideration when making a diagnosis. An intraoperative biopsy is necessary, therefore, even when the features seem to clearly indicate inoperable carcinoma.

Aged↗

PubMed1994

[Superior vena cava-right atrial appendage direct anastomosis for repair of partial anomalous pulmonary venous connection to superior vena cava].

Successful repair was performed for a 7-year-old male with a diagnosis of partial anomalous pulmonary venous connection (PAPVC) to superior vena cava (SVC) and superior sinus venosus atrial septal defect (ASD). The SVC was divided above the orifice of the anomalous pulmonary vein and the cephalad end of the SVC was anastomosed directly to the right atrial appendage. A patch was used to divert pulmonary venous flow from the orifice of the SVC through superior sinus venosus ASD into the left atrium. Postoperative course was uneventful with normal sinus rhythm. There was no evidence of vena caval or pulmonary venous obstruction. At 3-month after surgery, sinus node function was confirmed to be normal by electrophysiological study. This is useful alternative method for repair of PAPVC to high or middle SVC.

Anastomosis, Surgical↗

PubMed1994

Changes in regulating blood coagulation in hepatic resection with special references to soluble thrombomodulin and protein C.

The protein C anticoagulant pathway in hepatic resection was studied. The patients were divided into two groups--group 1 consisted of patients with a normal liver and group 2 consisted of patients with either hepatitic or a cirrhotic liver. Plasma protein C activity and soluble thrombomodulin were then sequentially measured during hepatectomy and in the early postoperative period. The protein C activity in group 1 decreased during hepatectomy and reached a low immediately after operation, and thereafter, recovered to near preoperative levels. However, the preoperative value in group 2 was lower than that in group 1 and the postoperative values were significantly lower than those in group 1 (p < 0.05). The level of soluble thrombomodulin in group 1 decreased during hepatectomy but later returned to preoperative levels. However, in group 2, the preoperative value was higher than that in group 1 and the postoperative values were greater than that of the preoperative values, while the values were significantly higher than those in group 1 (p < 0.05). During hepatectomy, hypercoagulability may contribute to the low levels of protein C and soluble thrombomodulin. The postoperative significant increase of soluble thrombomodulin may, thus, indicate the occurrence of endothelial injury in the remnant liver. The sequential measurements of both parameters can, therefore, be useful in detecting coagulopathy and endothelial injury in hepatic resection.

Aged↗

PubMed1994

Effect of nafamostat mesilate on coagulation and fibrinolysis in hepatic resection.

The effect of nafamostat mesilate on coagulation and fibrinolysis was investigated in a study of 22 patients with hepatocellular carcinoma who underwent a hepatic resection. The patients were divided into two groups: group 1, control (n = 11) and group 2, those with the intraoperative and postoperative use of nafamostat mesilate (0.2 to 0.4 milligram per kilogram per hour, n = 11). Nafamostat mesilate tended to suppress the coagulation expressed by thrombin-antithrombin III complex and fibrinopeptide A both during and immediately after operation. Moreover, nafamostat mesilate significantly suppressed the fibrinolysis expressed by euglobulin lysis activity both during and after operation. With regard to the initial stage of the fibrinolytic system, such as tissue-type plasminogen activator and plasminogen activator inhibitor-1, there was no difference between the groups. Therefore, the suppression of the euglobulin lysis activity may be caused by the inhibition of plasmin activity. There was no difference between the groups regarding operative blood loss. However, the rate of blood transfusion in group 2 was lower than that in group 1, and no fresh frozen plasma was required for the patients who lost over 2,000 milliliters of blood. Nafamostat mesilate can suppress euglobulin lysis activity both intraoperatively and postoperatively, and thus decrease the amount of blood transfusion needed. Therefore, at present, nafamostat mesilate seems to be one of the most useful agents for stabilizing the coagulant and fibrinolytic systems in hepatic resection.

Aged↗

PubMed1994

[Experimental hydrocephalus induced by intraplacental mumps virus inoculation].

Experimental production of congenital hydrocephalus was undertaken by inoculating mumps virus into pregnant hamsters intravenously or intraplacentally. When the mumps virus was inoculated intravenously on the 8th, 10th, 12th, or 14th day of gestation, some fetuses were aborted and those which could come to term did not develop hydrocephalus after birth. Offsprings from the mothers, which had had intraplacental inoculation on the 14th day of gestation, showed ventricular dilatation in about 28%. Histological examination revealed inflammatory infiltration on the surface of ependymal layers, subependymal edema and microglial activation in the underlying ependyma of the aqueduct. These findings were thought to have resulted from ependymitis caused by mumps virus. The transplacental infection of mumps virus is considered to be extremely rare. However, in such conditions as the placental barrier is impaired, mumps virus will possibly pass through the placenta, and will cause hydrocephalus to the infant.

Animals↗

PubMed1994

Repeat hepatectomy for recurrent hepatocellular carcinoma.

BACKGROUND: The significance of repeat hepatectomy for recurrent hepatocellular carcinoma remains controversial. Therefore the aim of this study was to reevaluate both the survival and the surgical risks of repeat hepatectomy. METHODS: The significance of repeat hepatectomy including the survival and the surgical risks for recurrent hepatocellular carcinoma were investigated with 21 patients who underwent a curative repeat hepatectomy during the period between May 1975 and July 1993. For a comparison of survival, 253 patients who underwent a curative primary hepatectomy during the period between April 1985 and July 1993 were used. Moreover, the preoperative liver function tests were also compared between the first and second hepatectomies. RESULTS: Regarding the preoperative liver function tests, the indocyanine green dye excretion rate at 15 minutes in the second hepatectomy (18.7% +/- 8.7%) was significantly higher than that in the first hepatectomy (14.7% +/- 5.9%). With regard to the surgical risks, there was no difference in the clinical parameters for blood loss, operation time, and the incidence of postoperative complications between the first and second hepatectomies. The postoperative hospital stay for the second hepatectomies was relatively shorter than that for the first hepatectomies. In addition, the patient's survival and disease-free survival after a curative repeat hepatectomy were almost identical to that after a curative primary hepatectomy. CONCLUSIONS: A curative repeat hepatectomy is thus considered to be the most effective therapeutic modality for recurrent hepatocellular carcinoma.

Adult↗

PubMed1994

Isolated hepatic caudate lobectomy.

BACKGROUND: Isolated caudate lobectomy is a challenging surgical procedure for which safe and reliable techniques have yet to be developed. METHODS: Isolated caudate lobectomy was performed by initial inflow control of the caudate lobe, full mobilization of the liver from the inferior vena cava by dividing all short hepatic veins, and parenchymal division dorsal to the major hepatic veins with a clockwise rotation of the liver while the liver was selectively devascularized by Pringle's maneuver and occlusion of the confluence of the major hepatic veins flush with the inferior vena cava. RESULTS: Two patients with cirrhosis underwent this procedure successfully without intraoperative hemodynamic instability or postoperative liver dysfunction. CONCLUSIONS: This technique allows safe and truly selective excision of the caudate lobe without the need for occlusion of the inferior vena cava or venovenous bypass.

Carcinoma, Hepatocellular↗

PubMed1994

Regional differences in glucose transport in the mouse hippocampus.

In order to observe glucose transport into the brain, 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-6-deoxyglucose (NBDG), a non-metabolizable and fluorescent glucose analogue, was injected intravenously into mice. After ascertaining that this glucose analogue is non-metabolizable in the brain, the NBDG contents in the blood and brain were measured quantitatively by spectrofluorimetry at 0, 0.5, 2, 5, 10 and 30 min after intravenous injection. The NBDG content in the blood decreased markedly with time, whereas in the brain it rapidly decreased, then gradually increased after 2 min. Glucose transport into the hippocampus was observed with a confocal laser scanning microscope. At 0.5 min, NBGD was seen to be highly concentrated on the vascular wall. Using the confocal mode, it was found that the fluorescence was unevenly distributed on the microvessel wall, suggesting local differences of glucose transport in the vascular wall. At 5 min, the fluoresent intensity of the vascular wall was markedly decreased, whereas relatively intense fluorescence was observed in the cerebral parenchyma of the stratum lacunosum-moleculare and stratum pyramidale of Ca3. At 10 min, a weak fluoresence was diffusely distributed in the hippocampus. As to the localization of NBDG in the brain, capillary endothelium (luminal and abluminal membrane), basement membrane, and the feet of the astrocytes are discussed.

4-Chloro-7-nitrobenzofurazan↗

PubMed1994

[A case of clinical Reye syndrome with symmetrical abnormal signal areas in the pons and thalami by MRI].

We report a two-year-old boy with clinical Reye syndrome. Brain CT disclosed symmetrical low-density areas in the pons and thalami, a part of which was recognized as being of high-intensity on both T1 and T2 weighted MRI. These lesions were suspected of being caused by vascular involvement, since the methemoglobin induced by bleeding may have contributed to the high-intensity regions. The lesions gradually disappeared within four months after the onset, and clinical symptoms also improved markedly without serious neurologic impairment. This case was characterized by the marked improvement in neurological and radiological findings in spite of the serious neurological involvement at onset.

Child, Preschool↗

PubMed1993

Isolation and expression of a cDNA encoding a male-specific rat sulfotransferase that catalyzes activation of N-hydroxy-2-acetylaminofluorene.

A cDNA (ST1C1 cDNA) encoding a N-hydroxyarylamine sulfotransferase (HAST-I) was isolated from a liver cDNA library of a male adult rat and was expressed in COS-1 cells. ST1C1 cDNA (1363 base pairs) encoded a protein of 304 amino acids with a molecular mass of 35,768 daltons, which shared 50.7 and 46.1% sequence identity with rat aryl (ST1A1 (PST-1)) and estrogen (rOST) sulfotransferases, respectively. N-terminal amino acid sequences of three digested polypeptide fragments of HAST-I were completely identical with two portions of the ST1C1 amino acid sequence. The profile of age- and sex-related expression of ST1C1 mRNA was quite consistent with changes in the sulfating activity of N-hydroxyarylamine and HAST contents in rat livers. ST1C1 expressed in COS-1 cells catalyzed a sulfation of N-hydroxy-2-acetylaminofluorene (N-OH-AAF) at a rate of 4.98 nmol/mg of protein/min and mediated PAPS (3'-phosphoadenosine-5'-phosphosulfate)-dependent DNA binding of N-OH-AAF. Although ASTIV was believed to be responsible for the activation of N-OH-AAF, ST1A1 encoding an arylsulfotransferase ASTIV, showed only a marginal activity in a sulfation and covalent binding of N-OH-AAF. These data clearly indicate that ST1C1 cDNA codes a new form of a male-dominant sulfotransferase (HAST) responsible for the bioactivation of N-hydroxyarylamines in rat livers.

Amino Acid Sequence↗

PubMed1993

Expression of platelet-derived growth factor beta receptor on human monocyte-derived macrophages and effects of platelet-derived growth factor BB dimer on the cellular function.

Platelet-derived growth factor (PDGF) plays an important role in the process of atherosclerosis which is characterized by the presence of macrophage-derived foam cells. In the present study, the induction of the mRNA of PDGF-beta receptor was demonstrated during cell differentiation of human monocyte-macrophages, whereas no mRNA was detected in the cells during the early days of culture. Flow cytometry analysis using antibodies specific for PDGF-beta receptor and CD14 showed the presence of both PDGF-beta receptor and CD14 on human monocyte-derived macrophages, whereas no PDGF-beta receptor was detected on human monocytes 4 h after cell adhesion to a culture dish. In the binding assay of PDGF-BB on human monocyte-derived macrophages, a saturable and high affinity binding site with Kd of 27.5 pM and Bmax of 23.3 fmol/mg of cell protein was demonstrated. When human monocytes were cultured in the presence of the protein kinase C inhibitor staurosporine, PDGF-beta receptor induction was inhibited, and tetradecanoylphorbol acetate enhanced PDGF-beta receptor expression in human monocyte-derived macrophages, indicating that PDGF-beta receptor expression is associated with maturation and differentiation of monocyte-macrophages through the activation of protein kinase C. In response to PDGF-BB homodimer, PDGF-beta receptor was phosphorylated, and thymidine uptake and inositol trisphosphate production were stimulated in monocyte-derived macrophages. Furthermore, PDGF-BB suppressed the production of macrophages colony-stimulating factor in macrophages. The expression of PDGF-beta receptor on human monocyte-derived macrophages suggests that PDGF influences the process of atherosclerosis by regulating the function of macrophages as well as smooth muscle cells in the vascular wall.

Animals↗

PubMed1993

[X-ray VTR analysis of esophagocardiac motion in cases of cervical dysphagia].

Using X-ray VTR motion analysis to diagnose a total of 103 cervical dysphagial cases, we obtained the following conclusions. Among these dysphagial cases, there were only 32 cases (31%) of clear organic or functional disease which we commonly considered to be the cause of dysphagia, and there were no less than 71 cases (69%) in which we could not identify the cause of the dysphagia. In 29 of these 71 cases, recording conditions of whole esophageal systole and diastole through the passage of contrast medium (Barium) were insufficient. We compared the remaining 42 cases with 42 normal cases, focussing on the lower esophagocardiac movement. In these dysphagial cases, angle of barium inflow tended to steepen statistically, and Barium discharge of the ampulla was tended towards incomplete discharge. In conclusion, this method is thought to contribute to the diagnosis of dysphagial cases except clear organic or functional diseases which we commonly consider to be the cause of the dysphagia.

Deglutition Disorders↗

PubMed1993

Overexpression of human lipoprotein lipase in transgenic mice. Resistance to diet-induced hypertriglyceridemia and hypercholesterolemia.

Lipoprotein lipase (LPL) is a key enzyme in the hydrolysis of triglyceride-rich lipoproteins. To determine the role of LPL in lipoprotein metabolism, we established three transgenic mouse lines overexpressing the human LPL gene; the highest expressor line, which transcribed human LPL mRNA in the heart, skeletal muscles, and adipose tissue, was used in this study. The transgenic mice had 5- and 1.7-fold higher LPL activity in adipose tissue and post-heparin plasma, respectively. Plasma triglyceride levels in transgenic mice were 24.2% of that in control mice, and gel filtration chromatography showed that very low density lipoprotein (VLDL) triglycerides were much reduced in transgenic mice. In the chemical analysis of plasma lipoproteins isolated by ultracentrifugation, we found that LDL particles were cholesterol-rich and HDL2 cholesterol was increased 1.4-fold in transgenic mice as compared to control mice. When we injected 125I-VLDL intravenously into transgenic mice, the clearance of 125I-VLDL and the conversion of VLDL to LDL was markedly enhanced as compared to control mice. Furthermore, the clearance of chylomicrons, estimated by both the fat loading and retinyl palmitate loading tests, was significantly enhanced in transgenic mice. After sucrose feeding, no increase in VLDL was observed in transgenic mice. When fed a high cholesterol diet, the development of hypercholesterolemia was suppressed in transgenic mice. These results suggested that LPL determined not only hydrolysis of triglyceride-rich lipoproteins but also lipolytic conversion, and that overexpression of LPL acted to protect against diet-induced hypertriglyceridemia as well as hypercholesterolemia.

Actins↗

PubMed1993

[X-ray VTR analysis for the inflowing movement of the contrast medium in the esophagocardiac region: the inflowing movement of contrast medium on healthy people].

The application of S-VHS video system has made it possible to easily detect the functional disease. Among several position, left posterior prone position where gravitational force could be ignored, and spontaneous, physiological movement could be registered in the recording of the esophagocardiac movement. Through the observation and the classification of the movement at this position, we evaluated the contribution of this method to the assessment, and the study of the functional diseases such as achalasia, hiatus hernia, and the study of the organic diseases such as carcinoma. In our present study on normal 60 cases, the time from the inflowing first phase to the inflowing interrupted phase in the last period becomes longer as the age of the subjects gets older. The continuous contractive period was divided into three types, shorter type, medium type and longer type. The shorter type seems to correspond to the type closer to hernia. The longer type is regarded as the type closer to achalasia.

Cardia↗

PubMed1993

Regulation of hyaluronate production by interleukin 1 in cultured human chorionic cells.

Human chorionic cells in culture synthesized and secreted a large amount of hyaluronate as well as tissue collagenase. When these cells were treated with human recombinant interleukin 1 alpha (hrIL-1), the biosynthesis and secretion of hyaluronate were predominantly accelerated, but those of sulfated glycosaminoglycans were not modulated. This promotive effect of hrIL-1 was not due to the increase in endogenous prostaglandins including prostaglandin E2 since cyclooxygenase inhibitors, indomethacin and diclofenac did not modulate the IL-1-mediated production of hyaluronate. On the other hand, the cotreatment of chorionic cells with hrIL-1 and cycloheximide suppressed the IL-1-mediated hyaluronate production, suggesting that protein, de novo, synthesis required for the enhancement of hyaluronate synthesis. Upon treatment with hrIL-1, the membrane bound-hyaluronate synthase activity was increased up to 5-fold in a time-dependent manner. On the other hand, when chorionic cells were treated with hrIL-1 and/or protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methyl-pyperadine hydrochloride (H7), the IL-1-mediated production of hyaluronate was effectively suppressed. Similarly, H7 effectively suppressed the protein kinase activator, 12-O-tetradecanoyl-phorbol-13-acetate-enhanced production of glycosaminoglycans with a similar extent. These results indicate that IL-1-induced acceleration of hyaluronate production was reflected on the increase in hyaluronate synthase activity, and that protein kinase C participates positively in the IL-1-signal transduction for the increased synthesis of hyaluronate in human chorionic cells.

Cells, Cultured↗

PubMed1993

Cholesteryl ester transfer protein deficiency caused by a nonsense mutation detected in the patient's macrophage mRNA.

Cholesteryl ester transfer protein (CETP) deficiency causes marked elevation of plasma high-density lipoproteins, termed hyperalphalipoproteinemia. Only one CETP mutation has been found previously, partly because the relative unavailability of CETP mRNA has hampered analysis. We demonstrated CETP mRNA expression in the monocyte-derived macrophages and identified a new CETP mutation by analyzing the macrophage mRNA of a homozygous patient with familial form of hyperalphalipoproteinemia. The nonsense mutation at codon 309 in exon 10 of the CETP gene was thought to delete the carboxy-terminal third and caused a decrease in the level of CETP mRNA. Our findings provide more evidence that CETP mutations may underlie a subset of familial hyperalphalipoproteinemia.

Base Sequence↗

PubMed1993

Effect of diabetes mellitus on hepatic resection.

We evaluated the effect of diabetes mellitus on mortality and morbidity after elective hepatic resections. Of 209 patients who underwent hepatic resections between April 1985 and July 1990, 49 (23.4%) were diabetic. Postoperative morbidity was more common among diabetics than among nondiabetics (75.5% vs 51.3%), mainly due to hepatic decompensation (55.1% vs 36.3%) and intraperitoneal sepsis (18.4% vs 6.3%). However, their incidence of hospital death (2% vs 2.5%), mean +/- SD postoperative hospital stay (36.1 +/- 20.2 days vs 29.4 +/- 28.2 days), and long-term survival were comparable with those of nondiabetics. Diabetics with and without complications were similar in preoperative or postoperative insulin requirement, duration of diabetes, and preoperative fasting glucose. Nevertheless, all eight patients with 24-hour urinary glucose excretion above 1 g developed complications. We conclude that diabetics are at a high risk of morbidity, but not of mortality after elective hepatic resection.

Adolescent↗