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Biomedical subjects

K Shimada

Publications and source records attributed to K Shimada.

At least 901 records · Page 50Linked to original sources

Management of gallstones in cirrhotic patients.

34 cirrhotic patients who underwent either cholecystectomy alone or in conjunction with common duct exploration were retrospectively reviewed. In Child A and B patients morbidity was low and there were no postoperative deaths. However, all patients who underwent additional cholecystectomy during the non-shunting operation for esophageal varices required blood transfusion. Cholecystectomy in Child C patients is frequently associated with considerable intraoperative bleeding and subsequent postoperative complications. In the 23 patients who were not operated upon for gallstones, no patients developed symptomatic biliary disease. Ultrasonographically, most of these gallstones were strongly suspected to be black stones. Elective surgical intervention for symptomatic Child A and B patients would normally be warranted, but hemorrhage and resulting complications due to additional cholecystectomy for asymptomatic gallstones during the non-shunting operation should be minimized. An additional cholecystectomy should be considered, provided such a cholecystectomy is thought to be easily performed judging from the degree of development of collateral circulation around the hepatoduodenal ligament and unless black stones are suspected ultrasonographically. For symptomatic gallstones in Child C patients every type of medical treatment should be attempted. After considering the bleeding tendency or ascites, percutaneous transhepatic gallbladder drainage is considered to be one of the safest treatments.

Adult↗

Amplification and detection of a single molecule of human immunodeficiency virus RNA.

Detection of plasma viremia in human immunodeficiency virus type 1 (HIV-1)-infected people is indispensable for the diagnosis of seronegative infection as well as for the evaluation of virus activities in vivo. The direct detection of HIV-1 RNA in circulation has been performed by means of reverse transcription followed by polymerase chain reaction (RT-PCR). As an attempt to establish a highly sensitive assay, we evaluated the effects of two-step amplification with nested primers and double priming of reverse transcription on the sensitivity of RT-PCR. The sensitivity of two-step amplification was 100 times higher than that of one-step amplification. The double priming of reverse transcription further increased the sensitivity of the following two-step amplification 100 times, which appeared to be enough to detect HIV-1 RNA from as little as a 2.2 x 10(-4) TCID50 unit equivalent of culture supernatant of HIV-1-infected cells and a single molecule of HIV-1 gag complementary RNA synthesized by in vitro transcription. By use of this most sensitive assay, we successfully detected HIV-1 RNA in serum or plasma from all 22 patients with acquired immune deficiency syndrome (AIDS) or AIDS-related complex (ARC) and 13 out of 14 untreated asymptomatic carriers. Of 43 asymptomatic carriers under the treatment with interferon-alpha or azidothymidine, 17 cases showed negative results, indicating that the virus activity was suppressed by the therapeutics. We also noted the inhibitory effect of heparin on RT-PCR.

Base Sequence↗

Hemangioma of the left ventricular cavity: presumptive diagnosis by magnetic resonance imaging.

In a 16-year-old boy, magnetic resonance imaging (MRI) revealed a 1 x 1.5-cm tumor on a stalk attached to the anterior ventricular wall. The tumor showed homogeneous enhancement after the administration of gadolinium(Gd)-DTPA, indicating it was highly vascular. The tumor was excised during surgery and the histological examination led to a diagnosis of juvenile hemangioendothelioma. MRI therefore allowed a definitive diagnosis of cardiac hemangioma to be made preoperatively. This case represents the first reported instance of a benign left ventricular hemangioma diagnosed by MRI.

Adolescent↗

Serial changes in atrial and brain natriuretic peptides in patients with acute myocardial infarction treated with early coronary angioplasty.

To examine the role of brain natriuretic peptide (BNP) in acute myocardial infarction (AMI), we measured the plasma concentration of immunoreactive (ir) BNP together with that of atrial natriuretic peptide (ANP) over the 4-week course of AMI in 16 patients treated with early coronary angioplasty. Both the plasma ir-ANP and ir-BNP levels were increased on the first day of the infarction compared with the values in normal subjects. During the clinical course of the infarction, the plasma ir-ANP concentration soon decreased, while the plasma ir-BNP level remained elevated at 2 weeks after the infarction, also exhibiting a high level at 4 weeks. Plasma ir-BNP levels on day 1 or days 14 and 28 were inversely correlated with left ventricular ejection fraction obtained by left ventriculography at the acute or chronic phase, respectively. Plasma ir-BNP concentrations on days 14 and 28 were positively correlated with the maximal myosin light chain I level, an indicator of infarct size. These observations suggest that the plasma ir-BNP level increased to compensate for the ventricular dysfunction associated with the size of the infarct in AMI. BNP may act as a cardiac hormone in AMI, differing somewhat from ANP in its synthetic, secretory, or clearance behavior.

Angioplasty, Balloon, Coronary↗

Expression of intercellular adhesion molecule-1 on rat vascular smooth muscle cells by pro-inflammatory cytokines.

Infiltration of mononuclear cells is an early pathological finding in human and experimental atherosclerosis. However, the cellular and molecular basis for cell infiltration is incompletely understood. While the intercellular adhesion molecule-1 (ICAM-1) is expressed on endothelial cells and promotes the adhesion of mononuclear cells, there is little information on the expression of ICAM-1 on vascular smooth muscle cells (SMC). In this study, we investigated the expression of ICAM-1 on cultured rat SMC and its regulation by pro-inflammatory cytokines, interleukin 1 alpha (IL-1 alpha), interleukin 6 (IL-6) and monocyte chemoattractant protein 1 (MCP-1). In immunohistochemical staining, ICAM-1 molecules were constitutively expressed on the surface of SMC. In flow cytometric and ELISA analyses, ICAM-1 molecule expression on SMC was significantly upregulated by IL-1 alpha and MCP-1, but not by IL-6, in a dose-dependent manner. The effects of IL-1 alpha and MCP-1 were observed as early as 4 h. In Northern blot analysis, ICAM-1 mRNA was slightly detectable in unstimulated SMC, but its expression was clearly observed following exposure to IL-1 alpha or MCP-1. These results suggest that ICAM-1 on SMC, as well as on endothelial cells, could participate in the focal accumulation of mononuclear cells in human atherosclerotic lesions.

Animals↗

Suppressive effect of soybean milk protein on experimentally induced skin tumor in mice.

We studied the effect of soybean milk protein (SMP) in a two-stage carcinogenesis experiment on mouse skin. Mice were given soybean protein isolate (SPI) diet or SPI diet supplemented with SMP. After 4 weeks on the diets, the mice were shaved and a tumor initiator was applied. A tumor promotor was then applied twice a week on the same area of the skin throughout the experiment. After 20 weeks on the treatment, the percentage of tumor-bearing mice and the volume of tumor tended to be lower in the mice on the SMP diet than those on the SPI diet. The number of tumor was also significantly lower in the former group as compared to the latter group. There was no difference in growth between mice of the SPI and SMP groups. The results indicate the safety and the anti-carcinogenic effect of SMP in mice.

Animals↗

Vesicoureteral reflux in infants under one year old. Follow-up study and consideration on development of renal scarring.

In an attempt to clarify reflux nephropathy (RN), 67 infants aged under one year with vesicoureteral reflux (VUR) were retrospectively classified into two groups, non-surgical and surgical. They were evaluated on VUR grading, VUR spontaneous cessation rate, and incidence of scarring. As a whole, spontaneous cessation rate was 61 percent. The cessation rate was higher for infants with lower VUR grading. The average age at cessation was 2.5 years. Some patients showed no scarring at presentation despite severe VUR. However, most cases of renal scarrings at the time of presentation belonged to grade IV or V. Scarring advanced in 3 kidneys of the non-surgical group and in 13 kidneys of the surgical group. Of these 16 kidneys, 7 were rated as grade IV and 9 as grade V. An association between development of scarring and recurrent urinary tract infections was suggested.

Cicatrix↗

Anti-lymphocyte antibodies and circulating immune complexes in the sera of patients with myelopathy associated with human T lymphotropic virus type-I.

We measured levels of circulating immune complexes in the human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) by Raji cell assay and C1q binding assay using an enzyme-linked immunosorbent assay (ELISA). The levels of anti-lymphocyte antibody were also measured using normal donor peripheral blood T-lymphocytes. The levels of anti-lymphocyte antibodies were significantly higher in the sera of patients with HAM compared to controls (P < 0.01). The concentrations of immune complexes measured by Raji cell assay were also significantly higher in the HAM patients' sera than in controls. However, when levels of immune complexes were measured by C1q binding assay, there was no significant difference between HAM patients and controls. There was no significant difference in the levels of anti-lymphocyte antibodies and immune complexes between HTLV-I carriers and controls. Circulating immune complexes detected by the Raji cell assay did not include HTLV-I p-19 as detected by the indirect immunofluorescent method. Levels of anti-lymphocyte antibody were correlated with levels of circulating immune complexes as detected by the Raji cell assay in the sera of patients with HAM. These findings indicate that anti-lymphocyte antibodies and circulating immune complexes are present in the sera of HAM patients, and that the levels of complexes detected by Raji cell assay may reflect anti-lymphocyte antibody levels.

Adult↗

Treatment of residual instability and extensor lag in polydactyly of the thumb.

Extensor indicis tendon transfers were used in six cases with residual deformity of the thumb in polydactyly. The indication was extensor lag and instability of the interphalangeal joint. At mean follow-up of three and a half years, normal stability was improved. Full extension was achieved in three cases and two cases also derived some benefits from this operation. Alignment was improved in five cases.

Child↗

High-level expression of biologically active chicken prolactin in E. coli.

1. A large quantity of chicken prolactin (cPRL) was produced by manipulating the cPRL cDNA clone and an expression vector pKK223-3. To augment the production of the hormonal protein in E. coli, in addition to the potent tac promoter, a unique DNA linker containing a pair of Shine-Dalgarno sequences and a short preceding cistron sequence was inserted into adjacent 5'-region of the coding region. 2. In sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis, recombinant cPRL protein exhibited a molecular mass of 23 kDa. 3. The recombinant cPRL showed equivalent binding kinetics to an antiserum raised against turkey PRL. Also, this product increased the weight of pigeon crop sac mucosa to a degree comparable to that induced by turkey PRL. 4. These results indicate that this recombinant cPRL has immunological and biological activities identical to those of authentic avian PRL.

Amino Acid Sequence↗

Phase I/II trial of didanosine (2',3'-dideoxyinosine) in hemophiliac patients with AIDS or AIDS-related complex.

Forty-three hemophiliacs with AIDS or ARC received a daily dose of 334 or 500 mg didanosine (2',3'-dideoxyinosine or ddI) orally in 2 divided doses in phase I/II, open-label clinical trial conducted in Japan. Twenty-eight patients completed 6 months of therapy. There was an increase in circulating CD4(+) cells in 19 valuable patients from 91 +/- 25 (mean +/- SE) at entry to 131 +/- 38 at 24 weeks of therapy P = 0.01; Wilcoxon signed rank). Fourteen of 37 patients met the criteria for CD4 rise >/= 50/mm3 rise or >/= 50% increase from entry values) for more than 4 consecutive weeks. Twenty patients were p24 positive at entry. Nine out of the 10 evaluable patients (90%) showed a decline in p24 antigen at weeks 20-24 (P = 0.02). Thirty-five patients had symptoms related to HIV-1 infection at entry. Twenty-seven patients reported improvements in constitutional symptoms during therapy. Nine patients presented with possible drug-related adverse effects, and didanosine was discontinued in 6 patients (one each with edema; abdominal pain with anorexia; hematuria with edema and rash; sense of abdominal distension with anorexia; diarrhea and abdominal pain; and irritability). One patient had a transient increase in serum amylase level to twice the upper limit of normal, but he continued to receive the drug. These data suggest that didanosine was generally well tolerated in hemophiliacs with AIDS or ARC, and its administration correlated with improvement in constitutional symptoms and laboratory findings. The adverse effects of didanosine seen in this population were moderate to mild, and no complications related to hemorrhagic diathesis were observed, although the relative risk of acute pancreatitis in this population (while not seen in the present study to date) requires more study.

Journal Article↗

Enzyme immunoassay for plasma 25-hydroxyvitamin D3 employing immunoaffinity chromatography as a pretreatment method.

An enzyme immunoassay (EIA) of 25-hydroxyvitamin D3 [25(OH)D3] has been developed as a new methodology for measuring its plasma levels. Three anti-25(OH)D3 antibodies elicited against 25(OH)D3 3-hemisuccinate or -hemiglutarate conjugated with bovine serum albumin were used for this purpose. Two enzyme-labeled antigens were prepared by linking these haptens to beta-galactosidase employing the N-succinimidyl ester method. An EIA system, selected from several combinations of the antibodies and labeled antigens, exhibited higher sensitivity and specificity than those of the conventional competitive protein binding assay. However, direct measurement of plasma specimens gave lower values than those obtained from the ones which were pretreated with a Sephadex LH-20 column followed by a normal-phase high-performance liquid chromatography. This problem has been overcome by employing immunoaffinity chromatography (IAC). In IAC the homologous anti-25(OH)D3 antibody with that used in the EIA was immobilized as a pretreatment method. The IAC/EIA system developed in this study afforded reliable plasma 25(OH)D3 levels which were confirmed by serial dilution study and the recovery test. The 25(OH)D3 levels of healthy volunteers in the summer measured by this method were 25.2 +/- 6.2 ng/ml (n = 10).

Animals↗

Experimental study of the cause of myospherulosis.

To elucidate the nature of myospherulosis, the authors tried to produce this state in vitro by mixing vitamin E, oleic acid, linoleic acid, and lanolin with human blood components, such as whole blood, washed erythrocytes, plasma, and fixed erythrocytes, respectively. Myospherulosis was produced in all mixtures in these experiments. The authors concluded the following. A thin parent body wall of myospherulosis is formed initially as a result of the physical emulsion phenomenon between lipid-containing materials and blood. Erythrocytes then are enclosed in the parent body. The parent body membrane gradually is reinforced by the deposition of plasma proteins, which are insoluble in ethanol. Thereafter, the erythrocytes become endobodies by the deposition of their contents to the membrane of the parent body. The pores of the endobodies are formed in the process of erythrocyte degeneration. The contents of the erythrocytes, such as hemoglobin, would attach to the parent body. Thus myospherulosis would become complete. In humans, the characteristics of the parent body membranes differ from each other, depending on how much the hemoglobin or a part of the endobody membrane attaches to the parent body membrane.

Erythrocytes↗

Synergic activity of imipenem/cilastatin combined with cefotiam against methicillin-resistant Staphylococcus aureus.

The synergic activity of imipenem/cilastatin combined with cefotiam was studied in a mouse bacteraemia model. Combinations of imipenem plus cefotiam in ratios from 1:5 to 1:160 were more effective than either imipenem alone or cefotiam alone (P < 0.05). Synergy was observed against both beta-lactamase producing and beta-lactamase non-producing MRSA. Staggered combinations of imipenem with cefotiam (each drug was administered at a different time) were studied in an in-vitro pharmacokinetic system to clarify relationships between killing kinetics and pharmacodynamics of the combinations. In the in-vitro system, cefotiam (1 g over 30 min) administered 2 h after imipenem administration (250 mg over 30 min) reduced viable cell counts to an undetectable level and maintained this for 4 h, while the simultaneous administration of imipenem and cefotiam maintained an undetectable cell count for only 2 h. Furthermore, imipenem administered after cefotiam showed no synergy. These results indicate that the timing of dosing of each antibiotic influences synergy, and administration of cefotiam 2 h after imipenem is more effective than the other regimens.

Animals↗

Characterization of secretory intermediates of Serratia marcescens serine protease produced during its extracellular secretion from Escherichia coli cells.

The Serratia marcescens serine protease (SSP; 66 kDa) is synthesized as a precursor (preproSSP; 112 kDa) composed of the NH2-terminal signal peptide of 27 amino acids, the mature protease part and a large COOH-terminal domain. When the SSP gene is expressed in Escherichia coli under the control of the tac promoter, the mature enzyme is excreted into the medium through the outer membrane, whereas preproSSP and two proteins, C-1 (40 kDa) and C-2 (38 kDa), processed from the COOH-terminal domain, are accumulated in the membrane fraction. Although treatment of the intact cells with trypsin caused slight truncation of C-1 and C-2, the main parts of C-1 and C-2, both of which are detected in the outer membrane, were resistant to trypsin, even after the cells had been osmotically shocked. Consistent with this, a high content of beta-sheet structure in C-2 was suggested by marked heat-modifiability, as determined by their electrophoretic mobilities on SDS-polyacrylamide gel. These findings suggest rigid integration of C-1 and C-2 in the outer membrane. Upon induction of the tac promoter, rapid excretion of SSP into the medium was first accompanied by the accumulation of C-1 in the outer membrane, which was followed by conversion of C-1 to C-2. PreproSSP was not detected during the accumulation of SSP in the medium, but it was gradually accumulated after the accumulation of SSP had reached a plateau. In addition, preproSSP still containing the intact NH2-terminal signal peptide was completely digested with trypsin when added to osmotically shocked cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

Alterations in cytosolic calcium-binding proteins that increase felodipine fluorescence in spontaneously hypertensive rats.

OBJECTIVE: To clarify the role of calcium-binding proteins (CaBP) in hypertension. DESIGN: CaBP from several organs of spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto (WKY) rats were purified and their characteristics compared between the two strains. The CaBP were purified by applying the soluble cytosolic fractions from mesenteric vessels, heart, kidney and brain of 4- and 10-week-old SHR and WKY rats to a phenyl-Sepharose column. Felodipine binding to the purified CaBP was then measured. RESULTS: The fluorescence intensity of felodipine increased in a calcium-dependent manner when it bound to CaBP. The pK 0.5 Ca2+ values derived from the calcium ion-felodipine fluorescence curves for each CaBP preparation from organs of the two strains were similar, indicating that the calcium sensitivities of the CaBP to the felodipine binding process are similar in SHR and WKY rats. In 10-week-old SHR the mean levels of felodipine-bound CaBP in heart, brain and kidney were significantly altered compared with those in WKY rats. No such alterations were observed in heart, kidney and brain from 4-week-old SHR and WKY rats. Conversely, the mean levels of felodipine-bound CaBP in mesenteric vessels from 4- and 10-week-old SHR were reduced significantly compared with those of age-matched WKY rats. CONCLUSIONS: These results suggest that the levels of cytosolic felodipine-bound CaBP from heart, kidney and brain are altered in response to elevated blood pressure, and that reduced levels of felodipine-bound CaBP in the mesenteric vessels of SHR might be a primary characteristic of this rat strain.

Animals↗