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Biomedical subjects

H Imai

Publications and source records attributed to H Imai.

At least 433 records · Page 24Linked to original sources
PubMed1989

High-yield purification of the complex-forming glycoprotein in urine from normal and abnormal subjects.

Ordinary methods for purification of complex-forming glycoprotein (protein HC) or alpha 1-microglobulin, a protein closely related to protein HC, require either large volumes of urine or special collection of urine specimens from patients with tubular proteinuria. Here we describe a fast, efficient procedure for isolating protein HC in high yield from urines from healthy and diseased subjects, with use of Cibacron blue, hydroxylapatite, and gel chromatography. Using this procedure, we also obtained a considerable amount of polymeric protein HC from the urine of a patient with chronic renal failure. The pattern of charge heterogeneity and immunoreactivity with anti-protein HC differed between the polymeric and monomeric forms of protein HC. We also observed a variability in charge heterogeneity of protein HC among patients with renal disorders. These results demonstrate that this purification method is useful for further studies to elucidate the biochemical properties of protein HC and its clinical significance in renal disorders.

Alpha-Globulins↗
PubMed1989

Expression of envelope glycoprotein (E) of Japanese encephalitis virus by recombinant vaccinia virus.

Vaccinia virus recombinants inserted with cDNA clones of Japanese encephalitis (JE) virus envelope glycoprotein (E) gene were constructed. The E gene product was detected in the recombinant virus-infected BHK21 cells by immunofluorescence (IF) and Western blotting. The intensity of IF observed was higher by the recombinant of the TK promoter--P7.5 promoter--inserted cDNA construct than by the P7.5 promoter--TK promoter--inserted cDNA construct. The E gene product was hardly detected by the recombinant carrying the TK promoter only upstream to the inserted cDNA, although the glycoprotein E mRNA had been transcribed.

Animals↗
PubMed1989

Vascular "sphincter" and microangioarchitecture in the central nervous system: constriction of intraparenchymal blood vessels following a treatment of vasoconstrictive neurotransmitter.

The site of action of neuropeptide Y (NPY), a potent vasoconstrictive neurotransmitter, on the intraparenchymal blood vessels in the rat parietal cortex was demonstrated using a corrosion cast technique with scanning electron microscopy. Our observations were confined to the cortical area where the regional cerebral blood flow (rCBF) had been reduced significantly by in situ application of NPY. A striking finding in that area was the diffuse narrowing of the perforating arteries in the upper cortical layers. Ring-like compressions on the corrosion casts, presumably formed by active vascular sphincters along the arteries, capillaries and venules within the brain parenchyma, seemed to be more prominent in the perforating arteries of the NPY-treated cortex as compared with those of control cortex. We conclude that NPY-containing nerve fibers along the parenchymal blood vessels may take part in regulating the rCBF primarily by reducing the caliber of the proximal perforating arteries.

Animals↗
PubMed1989

[Cardiac rupture secondary to left ventricular venting].

The cases of two patients with cardiac rupture secondary to left ventricular venting are reported. In the first patient, who had an aortocoronary bypass grafting, rupture was found in the posterolateral wall of the left ventricle just before closing the chest. It was successfully managed by placing sutures. The cause of rupture was thought to be the advancing venting cannula tip introduced into the left ventricle from the superior right pulmonary vein. In the second patient, who had MVR, AVR, and VSD and ASD closure, rupture occurred in the posterior wall of the left atrium on the 4th postoperative day. The patient died instantly because of profound hemorrhagic shock. Rupture of the left atrium was thought to have occurred secondary to distension of the left atrial wall incurred by lifting the unusually large heart for inserting and removing the venting cannula. These experiences made us decide to abandon routine left ventricular venting.

Assisted Circulation↗
PubMed1989

[Purification of the Ro/SSA antigen and enzyme-linked immunosorbent assay for quantitation of the antibody].

Antibodies to the Ro/SSA antigen occur in patients with Sjögren's syndrome and other collagen diseases. In this study, we used ammonium sulfate precipitation, anti-Ro/SSA immunoaffinity chromatography and gel filtration to purify the Ro/SSA antigen from pig spleen. In addition, the normal human IgG affinity column chromatography was also used to adsorb nonspecific reacting materials as heterophile antigens which contaminated in preparations after immunoaffinity chromatography. On SDS-PAGE the purified Ro/SSA antigen migrated as 60K and 53K polypeptides bands and the antigenicity was observed on 60 K band. An enzyme-linked immunosorbent assay (ELISA) using the purified antigen was developed for quantitation of the antibody which was found to be sensitive, precise and specific. By the method, anti-Ro/SSA antibodies were detected in SLE (44%), MCTD (71%), PSS (50%), SjS (83%), RA (16%), PBC (23%), lupoid hepatitis (23%) but only 4% in normal controls. The purified antigen and ELISA method will provide beneficial tools for the investigation of autoimmune diseases.

Animals↗
PubMed1989

[Is left ventricular venting necessary in open heart surgery?].

In this study we intended to clarify the benefits of left ventricular venting by comparing the surgical results and clinical courses of 19 adult patients who underwent open heart procedures with venting and those of 44 adult patients who had open heart procedures without venting. All of the patients of both groups underwent operations for acquired heart diseases. The hospital mortality was 10.5% in the vent group and 2.3% in the no-vent group (NS). None of the deaths occurred due to the postoperative low output syndrome in either group. The incidence of spontaneous defibrillation was not different in the two groups, and no patients required postoperative IABP support in either group. The number of patients who needed catecholamine infusion for longer than 24 hours postoperatively were not statistically different in the two groups, and incidence of ventricular arrhythmias was not different in the two groups. The cardiac index determined 6 hours postoperatively was significantly higher in the no-vent group. The left atrial pressure in the no-vent group did not exceed 10 mmHg during cardiopulmonary bypass, if the central venous pressure was maintained below 7 mmHg. It was suggested that distension of the left ventricle and myocardial injuries do not occur during cardiopulmonary bypass without left ventricular venting, provided the central venous pressure is maintained below 6 or 7 mmHg.

Adult↗
PubMed1989

[Bacteriological, pharmacokinetic and clinical studies on cefpodoxime proxetil in the pediatric field].

In bacteriological, pharmacokinetic and clinical studies of cefpodoxime proxetil (CPDX-PR, CS-807), the following results were obtained: 1. Antibacteriological activity Antibacteriological activity of R-3746 (Na-salt of cefpodoxime), cefaclor (CCL), cephalexin, cefroxadine (CXD), cefazolin (CEZ), cephalothin (CET) and amoxicillin (AMPC) were studied against clinical isolated bacteria following as: Staphylococcus aureus (resistant or sensitive of methicillin), Escherichia coli (resistant or sensitive to CEZ), Klebsiella pneumoniae (resistant or sensitive to CEZ), Proteus mirabilis and Enterobacter cloacae. Antibacterial activities of CXD and CET, however, were not tested against methicillin resistant S. aureus (MRSA) or CEZ resistant E. coli and K. pneumoniae. R-3746 showed stronger activities than any of the other oral antibiotics against these strains except S. aureus against which it showed slightly less activity than AMPC. Most frequent MIC values of R-3746 to S. aureus, E. coli, K. pneumoniae and P. mirabilis were 1.56, 0.39, less than or equal to 0.10 and less than or equal to 0.10 microgram/ml, respectively. Against isolated strains of MRSA, MICs of R-3746 were higher than 25 micrograms/ml with 23 strains (77%), which were similar to MIC values of CCL and AMPC against these organisms. MIC values of R-3746 against CEZ resistant E. coli and K. pneumoniae were superior to MICs of other antibiotics, and the MIC50 value was 0.20 micrograms/ml. Against many isolated strains of E. cloacae MIC values of R-3746 were relatively high ranging 0.78 to greater than 100 micrograms/ml. MIC50 of R-3746 against E. cloacae was 12.5 micrograms/ml. 2. Absorption and excretion Serum concentration and urinary excretion of CPDX (the active form of CPDX-PR) were studied upon single oral administration of CPDX-PR at 3 mg/kg, 6 mg/kg (dry syrup) or 100 mg (tablet). The peak of serum concentration of CPDX was attained in 1-6 hours 1-4 hours and 2-6 hours after administration of CPDX-PR at the 3 different dosage levels, and they were 0.99-2.99 micrograms/ml, 4.30-7.05 micrograms/ml and 1.65-2.93 micrograms/ml, respectively. At 8 hours after administration, mean concentrations of CPDX for the 3 groups were 0.31, 0.83 and 0.66 micrograms/ml, respectively. As the average AUC's for the 3 groups were 8.16, 25.97 and 10.79 micrograms.hr/ml, respectively. Urinary recovery rates of CPDX for the 3 groups were 20.9-56.2, 28.3-49.7 and 35.1-50.4%, respectively in the first 8 hours after administration.

Absorption↗
PubMed1989

[Bacteriological, pharmacokinetic and clinical studies on cefteram pivoxil in the pediatric field].

Bacteriological, pharmacokinetic and clinical studies were done on the effect of cefteram pivoxil (CFTM-PI, T-2588) (10% granules), a new oral cephalosporin, in the field of pediatrics. The results are summarized below. 1. Antibacterial activities Antibacterial activities of CFTM against Staphylococcus aureus and Streptococcus pyogenes were studied comparatively with activities of cefaclor (CCL), cephalexin (CEX) and ampicillin (ABPC). MICs of CFTM against S. aureus were distributed in a range between 0.78 and 12.5 micrograms/ml, with a peak value of 3.13 micrograms/ml, which were similar to MIC ranges of CEX and CCL. MICs of CFTM against all strains of S. pyogenes were less than or equal to 0.025 microgram/ml, which were similar to MIC of ABPC. CFTM was approximately 2 to 3 folds more effective than CCL or CEX. 2. Absorption and excretion. Serum concentrations and urinary excretions of CFTM were determined in doses of 3 mg/kg (non-fasting) and 6 mg/kg (non-fasting and fasting). In non-fasting subjects, peak concentrations of CFTM in serum were dose-dependent and were 1.15-2.3 micrograms/ml and 1.8-3.6 micrograms/ml at 2-3 hours, 0.125-0.78 micrograms/ml and 0.245-0.97 micrograms/ml at 6 hours, respectively, for the 2 dose levels. Serum half-lives were 1.03-2.65 hours for the dose of 3 mg/kg and 1.07-1.83 hours for 6 mg/kg. In fasting subjects, the mean peak serum concentrations were 1.73 micrograms/ml at 2 hours and 1.13 micrograms/ml at 6 hours for the dose of 6 mg/kg. Urinary recovery rates in the first 6 hours varied 5.3-19.2%. 3. Clinical study Clinical efficacies were examined in a total of 41 cases including 9 cases of bacterial pneumonia, 10 cases of bronchitis, 11 cases of tonsillitis, 7 cases of urinary tract infections, 3 cases of scarlet fever and 1 case of otitis media. Clinical efficacies were excellent in 30 cases, good in 10 cases, poor in 1 case, hence the efficacy rate was 97.6%. All of the 28 bacteria identified in these cases were eradicated after CFTM-PI treatments. No noticeable abnormalities were found as side effects. An elevation of eosinophil, an increase of platelet count and elevations of GOT and GPT were observed in 3 patients.

Bacterial Infections↗
PubMed1989

[A case of bronchiolitis obliterans organizing pneumonia (BOOP) showing spontaneous regression after an open lung biopsy].

The patient was a 57-year-old Japanese male with dry cough, exertional dyspnea of 6 weeks' duration and bilateral basal pulmonary infiltrates, before a left thoracotomy for lung biopsy was performed in August 1984. Because the symptoms of the patient were not severe, he could be followed up without corticosteroid hormone treatment for 3.5 years, during which a spontaneous regression of both symptoms and objective findings were recognized, following the open lung biopsy. The primary pathological diagnosis of the case was an unclassified type of interstitial pneumonia, because the two lobes of the left lung showed diffuse alveolar septal fibrotic and inflammatory changes. However, granulation tissues in respiratory bronchioles were noted in tissue from the lingular segment and, after more careful observation, from the lower lobe (segment 8) (Fig. 9). Bacteriological cultures from fresh lung tissues were negative for microorganisms. From these clinical and pathological findings, this patient's pulmonary lesions were determined to be idiopathic BOOP.

Biopsy↗
PubMed1988

Hemiparkinsonism in monkeys after unilateral caudate nucleus infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP): behavior and histology.

Systematically administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is biotransformed into 1-methyl-4-phenylpyridinium ion (MPP+), which enters dopaminergic neurons via the dopamine uptake system to destroy nigral cells. Either MPP+ is retrogradely transported to the cell body after being taken up at the nerve terminals, or the dopamine uptake sites on the cell body and its dendritic processes are responsible for the toxin directly entering the neuron. Using a 200 microliter osmotic minipump, we administered 4 mg of MPTP HCl directly into the unilateral caudate nucleus, i.e., the dopamine nerve terminal area, of monkeys for 14 days. Persistent hemiparkinsonism began to appear in a week. Each monkey exhibited a flexed posture and hypokinesia of the contralateral limbs and circling toward the MPTP-treated side. These disturbances developed within 3 months and maintained a plateau for 3 months until the day of sacrifice. After treatment with apomorphine, there appeared a striking circling away from the MPTP-treated side. Selective cell loss in the MPTP-treated side of the substantia nigra pars compacta was found along the entire rostrocaudal extent relative to the untreated side. In conclusion, MPP+ uptake only at the dopamine nerve terminals and retrograde axonal transport to the cell body seemed sufficient to destroy nigral dopamine cells in the monkey.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1988

Serial assay for IGM anti-HBc in patients with anti-HBe-positive chronic hepatitis and its significance for long-term prognosis.

Serial assays for immunoglobulin M antibody to hepatitis B core antigen (IgM anti-HBc) were performed in 51 patients with antibody to hepatitis B e antigen (anti-HBe) in their sera. IgM anti-HBc was detected periodically and persistently in 8 (53%) of 15 patients with chronic hepatitis whose serum glutamic pyruvic transaminase (GPT) levels were elevated and was not detected in 36 patients with normal serum GPT levels. Antibody to delta agent was not detected in any of the patients. Of the eight patients positive for IgM anti-HBc, four had a high titer of IgM anti-HBc and either developed liver cirrhosis (three cases) or died due to massive hepatic necrosis (one case); the other four showed a low level of IgM anti-HBc and either recovered (two cases) or developed chronic persistent hepatitis (two cases). Of seven patients negative for IgM anti-Hbc, two had a fatty liver, and five, who had a history of blood transfusion, had chronic hepatitis. Thus, even though anti-HBe may be present, if the titer of IgM anti-HBc is high, the histological activity can be expected to increase, and the prognosis will be poor. If the titer of IgM anti-HBc is low, the histological activity may be expected to decrease, and the prognosis may be good. In patients with abnormally high serum GPT but without IgM anti-HBc, another type of hepatitis or a secondary form of liver disease should be considered.

Adult↗
PubMed1988

A case of cholangiocarcinoma detected after follow-up for seven years for thorotrast deposition.

A 73-year-old former soldier in whom a deposition of thorotrast had been detected 7 years previously was admitted to our hospital because of high fever and epigastric pain. He had been well with standard liver function tests within the normal range until 4 months before admission. Laboratory examination on admission showed marked abnormalities in the liver function tests and an elevated level of CEA. Abdominal ultrasonography and computerized tomography, which had shown no space-occupying lesion in the liver one year earlier, revealed an abnormal mass in the right hepatic lobe. Angiographic examination revealed low vascularity and encasement of the intrahepatic artery. The disease was diagnosed as thorotrast-induced cholangiocarcinoma. Despite chemotherapy, the patient's condition worsened rapidly and he died on the 78th day after admission. At autopsy, the primary tumor in the right hepatic lobe and metastatic nodular tumors throughout the liver were found. The histological diagnosis was cholangiocarcinoma. Thorotrast-induced liver cancers are inclined to grow rapidly, so early diagnosis of liver tumor accompanied by thorotrastosis is very difficult, as in this case. Repeated examinations at frequent intervals are required for early diagnosis.

Adenoma, Bile Duct↗
PubMed1988

A large inferior mesenteric-caval shunt via the internal iliac vein.

A large portosystemic shunt between the inferior mesenteric vein and the right internal iliac vein in a 28-yr-old non-cirrhotic man is presented. This collateral was discovered by ultrasound done as a screening examination for gastrointestinal bleeding. The direct communication of the inferior mesenteric vein with the internal iliac vein was demonstrated by computed tomography and percutaneous transhepatic portography. Surgical ligation of the collateral, performed to prevent future portosystemic encephalopathy, resulted in reduction of serum ammonia level and cessation of long-standing hemorrhoidal bleeding.

Adult↗
PubMed1988

Immunohistochemical demonstration of vasopressin nerve fibers in the cerebral artery.

Vasopressin-immunoreactive nerve fibers were demonstrated in the cerebral pial arteries by peroxidase immunohistochemistry. In the large pial artery (proximal part of the middle cerebral artery), they ran longitudinally to the long axis of the vessel. They ran in a spiral pattern in the distal part of the middle cerebral artery. Even in small arteries, vasopressin nerve fibers were found arranged in a longitudinal fashion. The present morphological data suggest that vasopressin nerve fibers in the cerebral artery may play a role in cerebral circulation.

Animals↗
PubMed1988

Effects of beta-blockers on the fall of pH in the early phase of ischemia in the isolated perfused rat heart: a nuclear magnetic resonance study.

To elucidate the role played by catecholamines in the early phase of ischemic derangement of the myocardial energy metabolism, effects of beta-blockers (propranolol, pindolol, and celiprolol) and isoproterenol, and of pretreatment with reserpine and 6-hydroxydopamine (6-OHDA), were studied using the isolated perfused rat heart. beta-Blockers and isoproterenol were infused for 12 min prior to induction of global ischemia. The myocardial energy consumption rate was assessed by calculating the product of left ventricular pressure and heart rate (LVP x HR). The myocardial cell creatine phosphate (CP), ATP and pH were determined with 31P nuclear magnetic resonance (31P-NMR). Global ischemia induced by cross-clamping of the aortic inflow line for 15 min resulted in falls in CP, ATP, and pH. Propranolol (6 x 10(-8) and 1.8 x 10(-7) mol/min) and pindolol (6 x 10(-7) mol/min) produced a decrease in LVP x HR and suppressed the pH fall during ischemia. Celiprolol was without significant effects on these two parameters. Isoproterenol (6 x 10(-12) mol/min) produced an increase in LVP x HR and tended to accelerate the pH fall. Catecholamine depletion with reserpine or 6-OHDA produced no beneficial effects on the pH fall. It was concluded that the beneficial effects of beta-blockers on the pH fall during early ischemia were not due to the specific beta-blocking action but to the nonspecific cardiodepressant effects of these compounds.

Adrenergic beta-Antagonists↗
PubMed1988

Differential action of nerve growth factor, cyclic AMP and neurotropin on PC12h cells.

Nerve growth factor (NGF) induced the activities of acetylcholinesterase (AChE) and Na+,K+-ATPase concomitant with neurite outgrowth in PC12h cells, while dibutyryl cyclic AMP (DBcAMP) caused the induction of AChE activity and neurite outgrowth but not Na+,K+-ATPase activity. A nonproteinaceous extract isolated from the inflamed skin of rabbits inoculated with vaccinia virus (Neurotropin) induced neurite outgrowth and cell surface change similar to NGF without affecting AChE activity. The results suggest that NGF, DBcAMP and Neurotropin act on PC12h cells through different mechanisms.

Acetylcholinesterase↗