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Biomedical subjects

Y Shimada

Publications and source records attributed to Y Shimada.

At least 415 records · Page 23Linked to original sources
PubMed1994

Alpha-fetoprotein-producing early gastric cancer accompanying liver cirrhosis: a case report.

A rare case of alpha-fetoprotein (AFP)-producing early gastric cancer with liver cirrhosis is presented. A 61-year-old man was admitted to Shimane Medical University Hospital in 1988 because of abnormal liver function test results suggestive of liver cirrhosis with mild elevation of AFP. Liver cirrhosis was confirmed laparoscopically and histologically. Gastric cancer was found in fluoroscopic and endoscopic studies. After partial gastrectomy, the serum AFP level fluctuated transiently within normal limits, and then gradually increased soon after the operation. Therefore, complication of hepatocellular carcinoma was suspected, but no tumor in the liver was detected by any imaging examination, including angiography. Two years after the operation, swelling of abdominal periaortic lymph nodes was noted at a periodic checkup, but still no hepatic tumor was found. At this point, AFP-producing gastric cancer was suspected, and an AFP staining test was carried out on the tissue of the resected specimen. AFP-positive cells were recognized immunohistochemically. Thus, we diagnosed the condition as post-operative recurrence of an AFP-producing gastric cancer accompanying liver cirrhosis.

Adenocarcinoma↗
PubMed1994

Epidural blood flow during prostaglandin E1 or trimethaphan induced hypotension.

To evaluate the effect of prostaglandin E1 (PGE1) or trimethaphan (TMP) induced hypotension on epidural blood flow (EBF) during spinal surgery, EBF was measured using the heat clearance method in 30 patients who underwent postero-lateral interbody fusion under isoflurane anaesthesia. An initial dose of 0.1 microgram.kg-1.min-1 of PGE1 (15 patients), or 10 micrograms.kg-1.min-1 of TMP (15 patients) was administered intravenously after the dural opening and the dose was adjusted to maintain the mean arterial blood pressure (MAP) at about 60 mmHg. The hypotensive drug was discontinued at the completion of the operative procedure. After starting PGE1 or TMP, MAP and rate pressure product (RPP) decreased significantly compared with preinfusion values (P < 0.01), and the degree of hypotension due to PGE1 remained constant until 60 min after its discontinuation. Heart rate (HR) did not change in either group. EBF did not change during PGE1 infusion whereas in the TMP group, EBF decreased significantly at 30 min and 60 min after the start of TMP (preinfusion: 45.9 +/- 13.9 ml/100 g/min. 30 min: 32.3 +/- 9.9 ml/100 g/min (P < 0.05). 60 min: 30 +/- 7.5 ml/100 g/min (P < 0.05). These results suggest that PGE1 may be preferable to TMP for hypotensive anaesthesia in spinal surgery because TMP decreased EBF.

Aged↗
PubMed1994

Phase II study of protracted infusional 5-fluorouracil combined with cisplatinum for advanced gastric cancer: report from the Japan Clinical Oncology Group (JCOG).

A phase II study of protracted infusional 5-fluorouracil (5FU) combined with cisplatin (CDDP) was conducted in patients with advanced gastric carcinoma. 55 previously untreated patients, including 40 patients with measurable disease, were treated with 5FU (800 mg/m2, days 1-5, protracted infusion) and CDDP (20 mg/m2, days 1-5, drip infusion). Objective tumour responses were observed in 17/40 (43%) patients with measurable disease. Median survival was 7 months. WHO grade 3 or 4 leucopenia occurred in 10/55 patients (18%) and grade 3/4 thrombocytopenia was observed in 4 patients (7%). A randomised trial including this regimen is now underway in a JCOG study.

Adult↗
PubMed1994

Age-related changes in the metabolism of acetylated low-density lipoproteins by peritoneal macrophages from C57BL/6CrScl mice.

Macrophages are major precursors of foam cells in atherosclerotic lesions. Acetylated low-density lipoproteins (acetyl LDL) taken up by macrophages through scavenger receptors are degraded by lysosomes and the released cholesterol is re-esterified, leading to foam cell formation. The ability of resident peritoneal macrophages from C57BL/6CrScl mice to form foam cells in relation to the donor age was assessed by the cholesterol esterification and the metabolism of acetyl LDL. The incorporation of 14C-oleate (complexed to albumin) into cellular cholesteryl esters in the presence of acetyl LDL (100 micrograms/ml) was significantly greater in macrophages from senescent mice (24-25 months) than in cells from young (3-4 months) mice (p < .001). The degradation and cellular association of acetyl LDL by macrophages from senescent mice were significantly greater than macrophages from mature mice, (p < .001 and p < .01, respectively), whereas the binding of acetyl LDL was similar in peritoneal macrophages from mature and senescent mice. These results suggest that the uptake and degradation of acetyl LDL, and the re-esterification by macrophages increase with advancing age and that the ability of macrophages to form foam cells increases with aging. The enhanced ability of senescent macrophages to form foam cells might contribute to the development and progression of atherosclerosis related to the aging process.

Aging↗
PubMed1994

Cloning and nucleotide sequence of cDNA encoding a lipase from Fusarium heterosporum.

Fusarium heterosporum produces a solvent-tolerant lipase. A 1.3-kbp lipase cDNA was isolated from the cDNA library by colony hybridization with an oligonucleotide probe corresponding to the N-terminal amino acid sequence. Nucleotide sequence analysis showed an open reading frame of 999 bp, and the deduced amino acid sequence contained the N-terminal sequence determined by Edman degradation and the consensus pentapeptide (-Gly-X-Ser-X-Gly-), which is conserved in lipase, esterase, and serine protease. The mature lipase consisted of 301 amino acid residues with a molecular mass of 32.7 kDa, preceded by the putative signal peptide or preprosequence. The enzyme was homologous to lipases from Humicola lanuginosa (39% homology), Rhizomucor miehei (32%), Rhizopus delemar (32%), and Rhizopus niveus (32%), and to mono- and diacylglycerol lipase from Penicillium camembertii (38%). Comparison of this lipase with these homologous enzymes suggested that the catalytic triad was composed of Ser144, Asp198, and His256, and that the oxyanion hole was formed with Ser 82.

Amino Acid Sequence↗
PubMed1994

Positional and fatty acid specificities of Geotrichum candidum lipases.

Geotrichum candidum ATCC34614 produces a major (I) and three minor (II, III and IV) forms of lipase with similar molecular masses, but different positional and fatty acid specificities. The major and one of the minor (II) forms were confirmed to cleave both the inside and outside ester bonds of triolein indiscriminately. The non-positional specificity was also retained on 1,3-dipalmitoyl-2-oleoyl-glycerol (POP) hydrolysis. In contrast, the remaining two forms (III and IV) showed unusual positional specificity; they cleaved the inside (2-position) ester bond of triolein at nearly twice the rate of cleavage at the 1(3)-position. The preference for the inside ester bond was increased upon POP hydrolysis.

Geotrichum↗
PubMed1994

Activity of CPT-11 (irinotecan hydrochloride), a topoisomerase I inhibitor, against human tumor colony-forming units.

CPT-11 (irinotecan hydrochloride, 7-ethyl-10-[4-(piperidino)-1-piperidino] carbonyloxy-camptothecin) is a semisynthetic camptothecin derivative developed in Japan. The inhibitory activity of CPT-11 against human tumor colony-forming units from freshly explanted human tumors was explored using a soft agar cloning system. Final CPT-11 concentrations of 0.3-3.0 micrograms/ml were used for a 1 h exposure. At a concentration of 3.0 micrograms/ml antitumor activity was seen against colorectal, ovarian, nonsmall-cell lung, breast cancer and mesothelioma colony-forming units. CPT-11 should have activity against a broad spectrum of tumors in patients.

Antineoplastic Agents↗
PubMed1994

Effect of chronic tobacco smoke exposure on the function of alveolar macrophages in mice.

We evaluated the effect of chronic tobacco smoke exposure on the function of the alveolar macrophage (AM) in mice. Tumor necrosis factor-alpha production of the AM triggered by lipopolysaccharides was smaller in smoke-exposed mice as compared to control mice but did not reach statistical significance (27.3 +/- 4.0 vs. 34.8 +/- 4.9 U/ml). The percentage of AM which did not phagocytize latex particles in the smoke-exposed mice was significantly larger than that in control mice (33.9 +/- 2.3 vs. 20.8 +/- 2.1%; p < 0.05). Ia antigen expression of the AM was significantly larger in smoke-exposed mice (cytotoxicity index: 0.180 +/- 0.033 vs. 0.038 +/- 0.0118; p < 0.01). The asialo-GM1 antigen expression was similar in both groups (0.949 +/- 0.007 vs. 0.961 +/- 0.011). Although the precise mechanisms of these functional changes of the AM by tobacco smoke exposure are not clear, they may have some immunological effects on the alveolar space.

Animals↗
PubMed1994

Purification and characterization of a carboxylesterase from Pseudomonas sp. KWI-56.

An intracellular carboxylesterase from Pseudomonas sp. was overproduced in E. coli, and purified to homogeneity by a combination of hydrogen bond chromatography, gel filtration, and hydrophobic interaction chromatography. Gel filtration and SDS-PAGE suggested that the purified enzyme consisted of two subunits of molecular mass of 28 kDa. Its isoelectric point was 5.9. The enzyme was thermolabile, and showed its maximum activity at 22 degrees C (pH 7.5). Methyl propionate was hydrolyzed at the highest rate among the fatty acid methyl esters tested. PMSF, DFP, PCMB, and HgCl2 inhibited the enzyme markedly, suggesting that serine and/or cysteine is in or near the active site.

Base Sequence↗
PubMed1994

Estimation of triggering work of breathing. The dependence on lung mechanics and bias flow during pressure support ventilation.

Work of breathing necessary to trigger a ventilator (WOBtr) was calculated during pressure support ventilation (PSV), and the effect of bias flow on WOBtr was evaluated. A spring-loaded bellows type lung model with two bellows placed in series was used to simulate spontaneous breathing. A Venturi mechanism of jet flow generated subatmospheric pressure inside the diaphragm bellows simulated inspiratory effort. The lung compliance (CL) was set at 0.3 L/cm H2O or 0.05 L/cm H2O. The airway resistance (Raw) was set at 5, 20, or 50 cm H2O/L/s. Pressure support levels were increased from 0 to 45 cm H2O. Sensitivity was set at 2 cm H2O. No bias flow was used at first. The WOBtr was calculated using a pressure-volume (P-V) loop derived from the diaphragm bellows movement during the triggering period. We determined WOBtr and its dependence on the various pressure support (PS) levels, CL and Raw. To evaluate the effects of bias flow on WOBtr and triggering delay, a ventilator was put in the PSV mode, with various bias flow rates (from 0 to 20 L/min) at a sensitivity of 2 cm H2O. We found that when no bias flow was used, WOBtr increased with an increase in both Raw and end-expiratory lung bellows pressure which was considered as auto-PEEP. With bias flow, both triggering delay and WOBtr increased. An increase in bias flow at a given PS level resulted in both decreased pressure support time and tidal volume (VT). It is concluded that the bias flow system is not desirable for use during PSV.

Airway Resistance↗
PubMed1994

[Influence of age on mouse pulmonary alveolar macrophage clonal growth].

Although monocyte influx has been suggested as the primary source of pulmonary alveolar macrophages (AM), increasing evidence from recent studies has indicated that AM may be sustained through a self-renewal mechanism. We evaluated the age-related changes of the clonal growth (colony formation) of AM in mice (C57BL/6N mice and senescence accelerated mice). The colony forming unit (CFU) of AM of 24 month old C57BL/6N mice was lower than that of AM of 4-month-old mice (p < 0.05). In SAMP6 (senescence accelerated mice), CFU of AM was decreased with aging (p < 0.05). In SAMR1 (controls for SAMP6), CFU of AM was decreased with aging (p < 0.001). In SAMR1, CFU of bone marrow (BM) adherent cells of 12-month-old mice was similar to that of 4-month-old mice. In SAMP6, CFU of BM adherent cells of 12-month-old mice was larger than that of 4-month-old mice (P < 0.005). It was concluded that the CFU of AM declined with aging, but the CFU of the BM adherent cells did not. The decline of the AM CFU may be partly responsible for the defect of the immune response of the alveolar space in the elderly.

Aging↗
PubMed1994

[Primary cell culture of esophageal cancer as an indicator of biological malignancy].

The predictability of the monolayer culture patterning of primary cell culture as an indicator of biological malignancy was described. The prognosis of patients whose cancer cells could grow in monolayer epithelial pattern were significantly lower than that of the "no tumor growth" group. Multivariate analysis indicated that monolayer culture status best correlated with a mortality rate nearly equivalent to the number of lymph node metastasis, and Akaike's information criterion revealed that monolayer epithelial growth is a predictive factor of hematogenous recurrence. The relation of oncogenes and suppressor genes to cell culture was also described. Monolayer epithelial growth may be indicative of such general characteristics as adhesion, motility, invasion and reproduction of cancer cells.

Cell Adhesion↗
PubMed1994

Effects of cyclochlorotine on myofibrils in cardiomyocytes and on actin filament bundles in fibroblasts in vitro.

The effects of cyclochlorotine (CC), a secondary metabolite of Penicillium islandicum, on cardiomyocytes and fibroblasts were investigated by fluorescent and electron microscopy. The in vitro application of CC on myocytes induced disruption of myofibrils and large accumulations of actin, myosin, alpha-actinin, and vinculin at the cellular processes. This agent also induced the formation of islands of myosin and alpha-actinin aggregates. Actin filament bundles in fibroblasts were either unaffected or disrupted completely, suggesting the presence of two, physiocochemically different, populations of fibroblasts. CC damage was dose-dependently reversible. Further studies will be required to explore the feasibility of using CC for analyzing the properties of contractile and/or cytoskeletal proteins.

Actins↗
PubMed1994

The effect of epidural morphine on human intestinal motility in the early postoperative period.

The early postoperative recovery of intestinal motility and the response of motility to epidural morphine were investigated in 20 patients. Periodic motor activities in the jejunum were recovered within 32 hours in all cases. The length of these cycles increased gradually from the 1st (23.2 min) to the 4th (41.7 min) postoperative day. Morphine and lignocaine were given through an epidural catheter. Morphine induced premature migrating motor complexes (MMC) in all cases, whereas lidocaine failed to evoke this response in every case. The mean duration (19.8 min) and maximal amplitude (62.8 mmHg) of the burst activities induced by morphine were significantly longer and higher than those occurring spontaneously (7.7 min and 35.6 mmHg, respectively). The intervals between the induced and the subsequent spontaneous contractions were the same as the intervals between spontaneous contractions. These observations indicate that epidural morphine induced premature MMC without interrupting recovery patterns from postoperative gastrointestinal paralysis.

Adult↗
PubMed1994

[Myocardial preservation by continuous perfusion of Krebs-Henseleit solution--the temperature dependency of the optimal perfusion pressure].

The aim of this study was to determine the temperature dependency of the optimal pressure in myocardial preservation by continuous perfusion with Krebs-Henseleit bicarbonate buffer (KHBB) solution. Hearts from Wistar male rats were perfused with KHBB solution and cardiac function (aortic flow) was measured using an isolated working rat heart preparation. In the preliminary experiment, hearts were then preserved using Langendorff perfusion with KHBB solution of 37, 20 or 4 degrees C for 2 hours at a perfusion pressure of 100 cmH2O. This was followed by 15 min of Langendorff perfusion (37 degrees C, 100 cmH2O) and 20 min working perfusion. The 37 degrees C group and 20 degrees C group exhibited better functional recoveries of aortic flow (%AF) in the post-preservation period compared to the 4 degrees C group. In the test experiment, hearts were preserved using Langendorff perfusion for 4 hours at 37 degrees C or for 8 hours at 20 degrees C at various perfusion pressures. At 37 degrees C, %AF after 4 hours of the preservation were 64.7 +/- 2.6, 69.0 +/- 3.2, 81.9 +/- 3.1, 94.7 +/- 3.3 and 63.5 +/- 4.0% (p < 0.05 vs the 100 cmH2O group) at the perfusion pressure of 100, 60, 20, 15 and 10 cmH2O, respectively. %AF after 8 hours of the preservation at 15 cmH2O was 56.3 +/- 2.5%. At 20 degrees C, %AF after 8 hours of the preservatin was 78.9 +/- 3.3, 81.9 +/- 2.3, 67.4 +/- 1.9 and 65.9 +/- 2.2% (p < 0.05 vs the 60 cmH2O group) at the perfusion pressure of 60, 30, 10 and 15 cmH2O, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Clinico-pathological study of malignant lymphoma of the central nervous system.

This report describes the clinico-pathological features of a group of 36 patients with malignant lymphoma of the central nervous system (CNS) who were treated at one institution between 1970 and 1993. All cases were B cell type lymphomas. The authors summarize the most salient findings with respect to clinical course, pathology, treatment and disease outcome, and emphasize the value of diagnostic and therapeutic modalities in the management of patients with primary CNS lymphoma.

Adolescent↗