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Biomedical subjects

M Sakai

Publications and source records attributed to M Sakai.

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

[Endourologic treatment of the upper urinary tract obstruction in the advanced cancer patients].

88 cancer patients with an upper urinary tract obstruction were endourologically treated. The obstructions were caused by metastasis or invasion of cancer in all patients. First we tried to insert a ureteral stent catheter (STENT). When it failed percutaneous nephrostomy (PCN) was performed. Initially 69 and 19 patients were treated by STENT and PCN, respectively. Of 69 patients with STENT, 13 received PCN later. The average survival of all patients after treatment was 5.7 months. About 60% of the patients were discharged from hospital. The patients treated by STENT and PCN survived for 5.4 months and 6.7 months in average. The STENT was changed 1.8 times on the average in all patients. 79% of the patients who had been treated by STENT experienced only one or two times of STENT changes before dying. Patency period of inserted STENT was studied. On the average the STENT occluded after 72.4 days. The patent period of STENT was longer in the patients group of prophylactic STENT insertion for hydronephrosis. The period was shorter in the patients who showed gross hematuria at the time of surgery. Patent period of STENT was not related to STENT size. Although survival was not so long, over 60% of the patients were able to return to their homes. Endourologic treatment of urinary obstruction was performed in only 6 patients in 1985. The number of such cases has been increasing gradually and currently 20 patients are treated annually. It is supposed that there are many more cancer patients with urinary tract obstruction in their end-stage.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Effect of anisotonic conditions on the transport of hydrophilic model compounds across monolayers of human colonic cell lines.

The effect of anisotonic solutions on the enhancement of the transport of hydrophilic model compounds across monolayers of Caco-2 and HT-29.cl19A intestinal epithelial cells was studied. In filter-grown monolayers of the highly differentiated villus-like Caco-2 cell line, a profound and dose-dependent drop in the transepithelial electrical resistance was found after apical treatment with a 30 or a 50% hypotonic solution (200 and 150 mOsmol, respectively). This drop was not observed after basolateral and two-sided application of a 50% hypotonic solution. During apical hypotonic treatment a 12- and 8-fold increase also was observed in transepithelial transport of two hydrophilic model compounds, i.e., fluorescein-Na and fluorescein-isothiocyanate-labeled dextran, MW 4000, respectively. Through confocal laser scanning microscopy, it was revealed that this enhanced transport was predominantly via the paracellular route. Moreover, morphological changes in the cell layers indicating cell swelling were observed after apical hypotonic, but not after basolateral or bilateral treatment, probably resulting from an incomplete regulatory volume decrease response. This swelling, and slight lateral retraction of the cells, allowed the hydrophilic compounds to pass between the cells. The effects of hypotonic challenge also were studied in monolayers of the more crypt cell-like HT-29.cl19A cell line. After apical hypotonic shock, these cells showed no effect on transepithelial electrical resistance, whereas an increase was observed after basolateral and bilateral treatment. Hypotonic shock failed to increase the transport of the hydrophilic model compounds in this cell line.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗
PubMed1994

[Dynamics of pleural liquid in hydrothorax].

The basics of pleural liquid dynamics are summarized. The normal pleural cavity contains a small amount of pleural liquid (0.1-0.3 ml/kg). Its protein concentration is about 1.0 g/dl and its pH is 7.6. The normal flow of pleural liquid is gravity dependent, and pleural liquid flows from the costal to the mediastinal region. In experimental hydrothorax, the pleural liquid was removed mainly via lymphatics. The turnover of the pleural liquid is rapid, and it depends on the area of contact between pleural liquid and pleural and on the blood flow to the pleura.

Animals↗
PubMed1994

[A case of idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia associated with chronic nephritis].

A 48-year-old female who had general fatigue was admitted to our hospital. She had swelling of the axillary, inguinal, and paraaortic lymph nodes and mediastinal lesions. Laboratory examinations showed anemia, polyclonal hyperimmunoglobulinemia with IgG 5570 mg/dl, renal dysfunction and interstitial changes of the lungs. Microscopic findings of hematoxylin-eosin staining in biopsy specimens of the left inguinal and axillary lymph nodes revealed increased levels of infiltration of mature plasma cells without evidence of malignancy. Immunoperoxidase staining showed intracytoplasmic polyclonal immunoglobulin. These findings were identical to those of idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia (IPL) described by Mori et al. (1980). The specimens also showed evidence of chronic nephritis with infiltration of lymph cells and a slight invasion of plasma cells. Accordingly this case was diagnosed as IPL with renal involvement, which is associated with chronic nephritis. Recently, five cases of IPL with renal dysfunction have been reported. In particular, two cases of IPL with renal dysfunction, which included our case, revealed an increased level of IL6. These findings suggest that the occurrence of renal involvement with IPL may be related to changes in IL6, which is an important factor in the pathogenesis of IPL.

Chronic Disease↗
PubMed1994

A clinicopathological analysis of early gastric cancer: retrospective study with special reference to lymph node metastasis.

We reviewed 217 cases of early gastric cancer (EGC) resected from 1978 through 1988. To determine the indications for curative resection by endoscopic mucosectomy (EM) for EGC, we paid special attention to lymph node metastasis examined after gastrectomy. The overall incidence of lymph node metastasis was 12.4%. It was 3.4% for mucosal (m-) cancer and 23.5% for submucosal (sm-) cancer. The maximum diameter of the lesion, depth of cancerous invasion, and location of the lesion showed positive correlations with lymph node involvement (p < 0.05). EGCs less than 20 mm in diameter had no lymph node metastasis. Pieces of mucosa about 20 mm in diameter on the average could be obtained with a single EM procedure. EGC with ulceration had a higher incidence of lymph node involvement than did that without ulceration. We conclude that if EM reveals an intramucosal gastric carcinoma less than 20 mm in diameter without ulceration, curative resection by EM is indicated.

Adenocarcinoma↗
PubMed1994

Endocytic pathway of scavenger receptors via trans-Golgi system in bovine alveolar macrophages.

BACKGROUND: The scavenger receptors are trimeric membrane glycoproteins present on the surface membrane of macrophages and macrophage-derived foam cells and are implicated in the deposition of cholesterol in the arterial walls during atherogenesis. This receptor mediates endocytosis of a diverse alley of negatively charged macromolecules including modified low density lipoproteins. EXPERIMENTAL DESIGN: We tried biochemical and morphologic approaches to elucidate in more detail the endocytic and intracellular pathway of the scavenger receptors during endocytosis of acetylated low density lipoproteins (AcLDL) and oxidized LDL (OxLDL) by bovine alveolar macrophages. Biochemically, cell interaction and subsequent intracellular degradation of AcLDL and OxLDL were examined using [125I]AcLDL or [125I]OxLDL. At the ultramorphologic level, the scavenger receptors were detected by a mouse monoclonal antibody against bovine macrophages, D2, with colloidal gold particles (AcLDL-Au or OxLDL-Au particles) as tracer of ligands. RESULTS: The biochemical studies demonstrated that after binding of AcLDL and OxLDL to the cell surface, these ligands were internalized and degraded intracellularly. Immunoelectron microscopy revealed that after a 2-hour incubation at 4 degrees C AcLDL-Au or OxLDL-Au particles were bound to the scavenger receptors present on the cell surfaces. Upon a temperature shift from 4 to 37 degrees C, these particles were concentrated in coated pits and internalized in endosomes. After subsequent dissociation of the particles from the receptors within the endosomes, the ligands were transported to secondary lysosomes, the receptors were transported to a trans-Golgi system. In the Golgi complex, the receptors were packed in secretory vesicles and recycled to the cell surface membrane. The transport and recycling of the receptors via the trans-Golgi system were completely inhibited by incubation below 18 degrees C or pretreatment with monensin. CONCLUSIONS: These results suggest that during endocytosis of modified low density lipoprotein, the Golgi complex plays a crucial role in sorting and recycling of the scavenger receptors in macrophages.

Animals↗
PubMed1994

Glutathione binding rat liver 13k protein is the homologue of the macrophage migration inhibitory factor.

We have cloned the cDNA of the rat liver 13k protein, that has glutathione binding activity, from a rat liver cDNA library. The nucleotide sequence of this cDNA predicts a protein of 115 amino acids. This protein has 99.1%, 89.6% and 73.0% homology with mouse, human and chicken macrophage migration inhibitory factor (MIF), respectively. This indicates that the rat liver 13k protein is homologue of the MIF. The N-terminal 25 amino acids show 35% sequence similarity with that of the rat glutathione transferase Yb subunit. Although the remaining C-terminal sequence has no sequence identity with glutathione transferase Yb subunit, about 50% homology was found, if conservative substitutions and gaps were taken into account. Northern blot analysis indicates that this gene is expressed in a wide variety of organs including brain, spleen, liver, muscle and kidney. Southern blot analysis suggests that the MIF gene has many pseudo-genes or/and closely related genes.

Amino Acid Sequence↗
PubMed1994

Protection against spinal cord ischaemia: one-shot infusion of hypothermic solution.

The protective effect of a one-short infusion of a range of low-temperature hypothermic solutions against spinal cord ischaemia was investigated. Forty rabbits were allocated into five groups each of eight animals. The abdominal aorta of each rabbit was clamped distal to the left renal artery, and also occluded for 30 min above the iliac bifurcation with an inflated 50-gauge French balloon catheter. Ringer's solution with lactate was infused through the catheter port distal to the balloon, at various temperatures (group I, uninfused control; group II, 33 degrees C; group III, 23 degrees C; group IV, 13 degrees C; and group V, 3 degrees C). The neurological status of the hind limbs was assessed on the second postoperative day using the criteria of Tarlov. A further eight rabbits underwent laminectomy at L2 or L3. Temperature probes were inserted into the spinal cord and the cord temperature monitored continuously during infusion in four rabbits from each of groups I and V. Spastic paraplegia occurred in five rabbits in group I, three in group II, and two in group III. Four rabbits in groups II and III, seven in group IV and all eight in group V showed complete recovery of neurological function. The infusion of 3 degrees C solution achieved significantly lower spinal cord temperatures in group V after aortic clamping, compared with the temperatures in group I (P < 0.001-0.005). It was concluded that protection against spinal cord ischaemia and prevention of postoperative paraplegia are promoted as the temperature of the hypothermic infusion solution is lowered.

Animals↗
PubMed1994

[Collagen diseases complicated with myelodysplastic syndrome (MDS)--report of three cases].

We presented three cases of collagen diseases complicated with myelodysplastic syndrome (MDS). To our knowledge, MDS following collagen disease is very rare, and only seven cases have been reported previously. First case (a 40-years old woman) had suffered from rheumatoid arthritis, systemic lupus erythematosus and Sjögren's syndrome for 16 years. Second case (a 65-years old woman) had suffered from rheumatoid arthritis for 15-years. Third case (a 63-years old woman) had suffered from progressive systemic sclerosis for 16 years. These patients developed MDS. After onset of MDS, cytopenia progressed rapidly within half a year. In the types of MDS, case 1 and case 2 had refractory anemia and case 3 had refractory anemia with excess of blasts and a preleukemic state. Case 2 had a clonal abnormality of haemopoietic stem cells. It is unlikely that MDS in our cases are caused by mutant agents or irradiation. These results suggest MDS may be contributed to long-term immunodysfunction found in these collagen diseases.

Adult↗
PubMed1994

[A case of left ventricular hemangioma].

Left ventricle hemangioma in a 54-year-old man is reported. He was admitted to our hospital for chest discomfort. Coronary angiograms showed normal coronary arteries and a contrast blush in the left interventricle septum. Transesophageal echocardiogram also demonstrated the small floating tumor in the ventricular septum below the right coronary cusp. With the aid of cardiopulmonary bypass, the tumor was resected completely through transaortic approach. Histological examination revealed capillary hemangioma. The patient had uneventful recovery. To our knowledge, this is the seventh case of a left ventricular hemangioma treated surgically reported in the world literature.

Heart Neoplasms↗
PubMed1994

[The effect of beta-adrenergic blockade on the plasma potassium elevation induced by acute respiratory acidosis during halothane or fentanyl anesthesia].

The effect of beta-adrenergic blockade on the plasma potassium elevation induced by acute respiratory acidosis (CO2 inhalation) was studied in adult mongrel dogs during halothane or fentanyl anesthesia. Twenty-two dogs were divided into 4 groups: halothane-control (HC, n = 15), halothane-beta-blockade (H beta, n = 8), fentanyl-control (FC, n = 15) and fentanyl-beta-blockade (F beta, n = 10). Beta-blockade was achieved by continuous infusion of propranolol. The maximum levels of plasma potassium after 14% CO2 inhalation were 5.0 +/- 0.7 mM (mean +/- SD) in HC, 6.1 +/- 0.8 mM in H beta, 4.3 +/- 0.4 mM in FC and 4.8 +/- 0.5 mM in F beta. With halothane anesthesia more prominent elevation was observed in the beta-blockade group (P < 0.05), but with fentanyl anesthesia this elevation was not significantly different between the two groups. In acute respiratory acidosis, pH-induced plasma potassium elevation is suppressed by simultaneously increased catecholamines, especially epinephrine. Beta-adrenergic blockade, therefore, may cause severe hyperkalemia due to inhibition of adrenergic potassium disposal. During fentanyl anesthesia plasma potassium elevation was less marked than during halothane. This indicates that fentanyl has less suppressing action on the secretion of stress hormones, including epinephrine, under similarly stressful conditions as halothane anesthesia.

Acidosis, Respiratory↗
PubMed1994

[The etiology and management of congestive heart failure in the elderly].

The common underlying heart diseases were ischemic heart disease (39%), valvular heart disease (27%), hypertensive heart disease (10%) in 104 patients (mean age 79 yrs) with congestive heart failure (CHF). Cardiomyopathy (5%) and congenital heart disease (2%) such as atrial septal defect were less common. In addition, many extracardiac diseases including anemia, hypothyroidism, renal failure and pulmonary disease contributed to the etiology of CHF in the elderly. Cardiac amyloidosis should be considered as an uncommon cause of refractory CHF. While the precipitating factor was not found in half of the 104 patients with CHF, the most common factors were respiratory infection, myocardial ischemia and arrhythmia. In addition, inappropriate drug usage including poor drug compliance, the use of beta-blockers and excessive intake of sodium and fluid precipitated or exacerbated heart failure. Renal failure was a most important complication and predisposed to refractory CHF. Aged patients with mild CHF (NYHA class II) showed an insufficient production of cyclic AMP and GMP in proportion to the increases of norepinephrine and atrial natriuretic peptide in comparison with health aged subjects after the submaximal treadmill exercise test. This finding may suggest that an inadequate compensation of neurohumoral factors is prone to cause CHF in the elderly. Appropriate management of acute CHF in the elderly begins with recognition of the underlying heart disease, complications and the severity of cardiac function. In addition to medical management including loop diuretics, vasodilator, beta-receptor agonist and phosphodiesterase inhibitor, cases associated with respiratory and renal failure require mechanical ventilation and continuous hemofiltration.

Aged↗
PubMed1994

[Clinical evaluation of endoscopic variceal ligation (EVL)].

From August 1992 through February 1993, we treated 21 patients with endoscopic variceal ligation (EVL). Two patients had a history of the esophageal variceal bleeding, but 19 patients did not have bleeding episodes. To evaluate preventive effect of bleeding, we selected the patients who had grade F2 or red color sign positive varices. We repeated EVL until varices improved into grade F0 or F1 and red color sign negative. The therapeutic goal was sometimes changed according to patient's general condition. No additional therapy was performed to eradicate varices, such as endoscopic injection sclerotherapy. As a result of our therapy, eradication rate was 73.7% and period of hospitalization were 25 +/- 11 days. No major complications were found during and after EVL. EVL affected neither liver function test nor size of gastric varices. Recurrent varices with red color sign were found in 4 patients, but easily controlled by retreatment with EVL. EVL seems to be convenient and effective therapy in our short-term study, and useful for preventive therapy of the esophageal variceal bleeding.

Aged↗
PubMed1993

The fatty acid binding site of human alpha-fetoprotein.

alpha-Fetoprotein (AFP) binds a series of endogenous fatty acids. To identify the fatty acid binding site, this protein, purified from umbilical cord blood by immunoaffinity chromatography, was covalently labeled using 12-(9-anthroyloxy) stearic acid conjugated with Woodward's reagent K. After digestion with lysyl endopeptidase, the fatty acid-labeled peptide was isolated. Amino acid sequence analysis showed that this peptide consisted of the amino acid residue 210-227. The fact that no appreciable PTH-amino acid was detected at 14th cycle on the degradation suggested that Lys223 was modified with the fatty acid. The finding that lysyl endopeptidase did not cleave off at the Lys223 supported this suggestion. These results indicate that the carboxyl group of the bound fatty acid is located close to Lys223 in human AFP.

Amino Acid Sequence↗
PubMed1993

Expression, purification and binding to the receptor of human insulin-like growth factor II.

Human insulin-like growth factor II (IGF-II) was expressed as a fused protein with 14 additive amino acids in Escherichia coli with a high yield by an expression system using T7 RNA polymerase. Purification of the expressed protein was simply performed using only differential ultrafiltrations, giving a homogeneous preparation upon polyacrylamide gel electrophoresis and high-performance liquid chromatography. The expressed peptide was reacted with a monoclonal antibody raised against native IGF-II on a blotted membrane. Furthermore, the peptide was bound to IGF-II receptor in solubilized rat fetus membrane, though the affinity was slightly inferior to that of native IGF-II. In addition, fusion IGF-II immobilized on a gel matrix was useful for one-step purification of the IGF-II receptor with a high yield from solubilized rat fetus membranes.

Amino Acid Sequence↗
PubMed1993

Two independent macrophage receptors for acetylated high-density lipoprotein.

We previously demonstrated that acetylated human high-density lipoprotein (acetyl-HDL) was recognized by a scavenger receptor of rat sinusoidal liver cells (Murakami, M., Horiuchi, S., Takata, K. and Morino, Y. (1987) J. Biochem. (Tokyo) 101, 729-741). The present study describes the interaction of acetyl-HDL with rat peritoneal macrophages in vitro. Acetylation of HDL enhanced its cell-association by 2-fold and cellular degradation by > 25-fold. The cell-association of [125I]acetyl-HDL was effectively inhibited by unlabeled acetyl-HDL (> 85%), whereas the inhibition by HDL or acetylated human low-density lipoprotein (acetyl-LDL) was partial (60% and 50%, respectively). However, when both HDL and acetyl-LDL were present, the cell-association of [125I]acetyl-HDL was effectively inhibited by > 80%, a level identical or closely similar to that by acetyl-HDL. The cellular degradation of [125I]acetyl-HDL was effectively suppressed by acetyl-LDL whereas the effect of HDL was much weaker. These findings indicate that acetyl-HDL is endocytosed by both the HDL receptor and the scavenger receptor for acetyl-LDL in which the ligands bound to the latter might be subjected to lysosomal degradation.

Acetylation↗