Biomedical subjects

K Shimada

Publications and source records attributed to K Shimada.

At least 1,765 records · Page 98Linked to original sources

PubMedDate not supplied

Biliary tract infection with anaerobes and the presence of free bile acids in bile.

Gallbladder bile from 24 patients (five with anaerobic biliary tract infection, 10 with aerobic biliary tract infection, and nine without biliary tract infection) was examined by thin-layer chromatography (TLC) for the presence of free bile acids. All five patients with an anaerobic biliary tract infection had small amounts of free bile acids in gallbladder bile. Seven of 10 patients with aerobic biliary tract infection and nine patients with sterile bile had no detectable free bile acids. Minute amounts of free bile acids were detectable on TLC in bile of three patients with aerobic infections. Calcium bilirubinate stones were more common in patients with free bile acids in bile.

Bacteria, Anaerobic↗

PubMedDate not supplied

Determination of glufosinate ammonium and its metabolite, 3-methylphosphinicopropionic acid, in human serum by gas chromatography-mass spectrometry following mixed-mode solid-phase extraction and t-BDMS derivatization.

A method for the analysis of glufosinate ammonium (GLUF) and its metabolite 3-methylphosphinicopropionic acid (MPPA) in human serum by gas chromatography-mass spectrometry (GC-MS) was developed. Employing a mixed-mode cartridge with both anion exchange action and weak nonpolar interaction, we extracted GLUF and MPPA from the serum and carried out GC-MS analysis of their tert-butyldimethylsilyl derivatives. The detection limits of GLUF and MPPA were 10 pg and 1 pg, respectively. Full mass spectra of 100 pg GLUF and of 10 pg MPPA were easily obtainable. The recovery rate of 90.0+/-11.9% (or better) when the serum concentrations of GLUF and MPPA were 10-0.1 microg/mL. Results of 23 serum samples, from patients with GLUF poisoning, measured by this method correlate well with those derived from the conventional high-performance liquid chromatography method (r = 0.996). The developed GC-MS method is likely to become a useful analytical technique in clinical settings.

Aminobutyrates↗

PubMedDate not supplied

CT of lymphoepithelial cysts of the pancreas.

OBJECTIVE: To clarify imaging and clinicopathologic features of lymphoepithelial cysts (LEC), a benign lesion of the pancreas. MATERIALS AND METHODS: Two male patients with LECs that were found incidentally and proven surgically were reviewed. RESULTS: Sonography revealed a hypoechoic mass in both cases, one of which had septation and an intracystic isoechoic component within it. The mass was shown as low attenuation on unenhanced CT, and the intracystic solid component was not enhanced by dynamic CT or computed tomographic arteriography. One lesion had calcifications around the mass. Magnetic resonance imaging showed hyper- in hypointensity on T1-weighted imaging and hypo- in hyper- on T2-weighted imaging in one case. Both lesions were located on the surface of the head of the pancreas, and the main pancreatic ducts appeared normal on endoscopic retrograde pancreatography. Both patients were asymptomatic. CONCLUSION: These imaging and clinical findings suggest LEC, which should be considered when one encounters cystic lesions of the pancreas.

Humans↗

PubMedDate not supplied

Choice of treatments for small hepatocellular carcinoma: hepatectomy, embolization or ethanol injection.

The results of hepatectomy, percutaneous ethanol injection therapy and transcatheter arterial embolization for small hepatocellular carcinoma (HCC) of 3 cm or less in diameter from the published literature were compared with the authors' experiences with surgical treatment. The survival rates for those treated by hepatectomy and ethanol injection were almost the same, being more than 90% at 1 year and 70% at 3 years. The overall results achieved by embolization were inferior to those achieved by the other two therapeutic modalities, although the 1 year survival rate was not worse. The cancer-free survival rates after hepatectomy and ethanol injection were also similar. Most of the patients with small HCC had associated liver cirrhosis or chronic active hepatitis, but the degree of liver dysfunction and the level of hepatic reserve varied. Anatomically, the number, size, and location of the cancer also varies. Choice of treatment for small HCC should be made based upon the degree of liver function and the anatomic status of the cancer. For example, a patient with multiple (more than four) cancer nodules is a good candidate for embolization. Ethanol injection is indicated for a small HCC, deeply seated in a severely diseased liver. Hepatectomy is the first choice for a small HCC situated near the surface of a liver with relatively good liver function.

Carcinoma↗

PubMedDate not supplied

Biliary bile acids in the gall-bladder and the common bile duct of patients with anomalous pancreaticobiliary ductal junction.

The high incidence of biliary tract carcinoma in patients with anomalous pancreaticobiliary ductal junction (APBDJ) with or without choledochal cyst (CC) has been well documented. Twenty-two patients with APBDJ were divided into three groups: Group A, four patients not associated with CC and biliary tract carcinoma; Group B, 13 patients with CC but without biliary tract carcinoma; and Group C, five patients with biliary tract carcinoma (four with and one without CC). Profiles of bile acids in the gall-bladder and/or common bile duct were analysed in these patients and compared with those in the control patients with cholecystlithiasis to examine the hypothesis that the levels of deoxycholic acid (DCA) and lithocholic acid (LCA) are elevated in patients with APBDJ because these secondary bile acids are mutagenic. Bile acids were quantified by gas-liquid chromatography. Total bile acid concentration in the gall-bladder bile was significantly lower in any group with APBDJ than that of controls. In the gall-bladder, increased proportion of chenodeoxycholic acid (CDCA) in Group A and B, decreased proportion of DCA in Group B and increased proportion of cholic acid (CA) in Group C were found in bile. In the bile duct, total bile acid concentration and proportion of DCA were significantly low in bile from Group C and decreased proportion of DCA and increased proportion of CDCA were found in bile from Group B. In both the gall-bladder and hepatic bile, proportion of LCA was not significantly different between any intergroups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMedDate not supplied

A new fluoroquinolone derivative exhibits inhibitory activity against human immunodeficiency virus type 1 replication.

The inhibitory activity of several fluoroquinolone antibiotics against human immunodeficiency virus type 1 (HIV-1) replication was investigated. R-71762, (+/-) 9-fluoro-3-fluoromethyl-2, 3-dihydro-10-[4-(2-pyridyl)-1-piperazinyl]-7-oxo-7H-pyrido[1,2, 3-de][1,4]benzoxazine-6-carboxylic acid, protected MT-4 cells from HIV-1-induced cytopathic effects. Furthermore, the compound inhibited virus replication both in acutely and in chronically HIV-1-infected cells. On the other hand, ofloxacin, levofloxacin, ciprofloxacin, norfloxacin and enoxacin, that were previously reported to be protective against HIV-1-induced cytopathic effects, did not show any protective activity in our assay system. These results indicate that R-71762 is a novel inhibitor of HIV-1 replication and is effective even in HIV-1 chronically infected cells.

Anti-HIV Agents↗

PubMedDate not supplied

Gene transfer into rat renal cells using adeno-associated virus vectors.

Adeno-associated virus (AAV) vectors have a number of attractive features, including lack of cytotoxicity, ability to transduce nondividing cells, and long-term transgene expression. We investigated whether rat renal cells could be efficiently transduced with AAV vectors. Rat glomerular mesangial cells were transduced with AAV-lacZ vector containing beta-galactosidase gene in vitro, and the expression of beta-galactosidase was evaluated by X-gal staining and ELISA. For ex vivo experiments, sections of rat kidneys were incubated with AAV-lacZ, and then evaluated by X-gal histochemical staining. The level of beta-galactosidase expression in cultured rat mesangial cells increased in a dose-dependent manner (ranging from 1 x 10(5) to 5 x 10(6) particles/cell). When transduced with 5 x 10(6) vector particles/cell of AAV-lacZ, about 50% of mesangial cells were stained positively with X-gal, and the level of beta-galactosidase expression reached 9.9 +/- 1.5 ng/mg protein. Expression was detectable during the culture period for at least 7 days. X-gal histochemical examination of the ex vivo transduced renal tissue revealed tubular cell and interstitial tissue staining. However, gene transfer was not clearly observed in glomeruli. These findings suggest that AAV vectors have the potential for gene therapy of renal diseases.

Animals↗

PubMedDate not supplied

Plasma endothelin-1 levels in Takayasu's arteritis.

We measured plasma endothelin-1 (ET-1) levels in patients with Takayasu's arteritis to investigate its relationship with the disease activity. We also measured plasma thrombomodulin (TM) levels as a marker of endothelial injury. A significant positive correlation was evident between plasma ET-1 levels and erythrocyte sedimentation rates (ESRs) in patients with Takayasu's arteritis (r = 0.53, p < 0.005). In contrast, plasma levels of TM did not show a significant correlation with ESRs (r = -0.13) ET-1, secreted in this way during the active stages of Takayasu's arteritis, may cause constriction and proliferation of vascular smooth muscle cells and, as a result, progression of luminal narrowing of the affected vessels in this disorder.

Biomarkers↗

PubMedDate not supplied

Plasma cytokine levels in cardiac chambers of patients with mitral stenosis with congestive heart failure.

To ascertain whether elevated levels of circulating proinflammatory cytokines in patients with advanced heart failure are due to congestive heart failure or due to cachexia or infection complicating heart failure, we measured prospectively plasma concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), interleukin 2 (IL-2), and interleukin-6 (IL-6) in 12 patients with mitral stenosis with moderate congestive heart failure, but not with cachexia or infection. Blood samples were obtained from the peripheral vein and right and left atria of the patients during percutaneous mitral valvuloplasty. Levels of TNF-alpha, IL-1 beta, IL-2, and IL-6 in the plasma form the peripheral vein and right and left atria of these patients were not elevated compared with those from the peripheral vein of a control group of 10 normal subjects. On the other hand, plasma levels of TNF-alpha but not IL-1 beta, IL-2 or IL-6, were elevated in 4 of 9 patients with congestive heart failure complicated with cachexia and/or infection. Our results suggest that proinflammatory cytokine levels are not elevated in congestive heart failure uncomplicated with cachexia or infection.

Adult↗

PubMedDate not supplied

Functional imaging of the human olfactory cortex by magnetic resonance imaging.

Our understanding of the neural mechanism of human olfaction is still equivocal. Several recent reports document that functional magnetic resonance imaging (MRI) has a potential to visualize dynamic brain function in humans without invasion. In the present study, we applied functional MRI with odor stimulation for the purpose of clarifying the localization of olfactory cortices in the human. We obtained a significant increase in cerebral blood flow in the piriform cortex, orbitofrontal cortex, and inferior medial frontal lobe, corresponding to olfactory cortices. These results suggest that, in the near future, precise diagnosis of the patients with olfactory disorders will be possible using functional MRI with odor stimulation.

Adult↗

PubMedDate not supplied

Modulation of glycosaminoglycan production and antithrombin III binding by cultured aortic endothelial cells treated with 4-methylumbelliferyl-beta-D-xyloside.

The interaction between antithrombin III and heparinlike glycosaminoglycan molecules present on the vascular surface seems to play a significant role in the regulation of coagulation. We have tested the hypothesis that altered synthesis of glycosaminoglycans by endothelial cells could influence this interaction by using 4-methylumbelliferyl-beta-D-xyloside for metabolic perturbation of glycosaminoglycan production. Incubation of purified porcine 125I-antithrombin III with cultured porcine aortic endothelial cells demonstrated specific, time-dependent, saturable binding of this protease inhibitor to the endothelial cell surface with antithrombin III concentration at half-maximal binding of approximately 40 nM. This binding was displaced by heparin and was completely abolished by selective removal of heparan sulfate from cells with heparitinase, indicating that antithrombin III binds to heparan sulfate on the surface of endothelial cells. Incubation of cell cultures with beta-D-xyloside resulted in a reduction of maximum antithrombin III binding by approximately 65% with little alteration in binding affinity. beta-D-Xyloside did not affect the cellular growth or morphology. Reduction of the binding after exposure to various concentrations (33 to 500 microM) of xyloside occurred in parallel with the decrease in incorporation of both 35S-sulfate and 3H-glucosamine into cell surface heparan sulfate. Whereas the size of heparan sulfate chains derived from the cell surface was not altered by xyloside treatment, they appeared to have slightly less net negative charge and a significantly reduced proportion of the molecule with high affinity for antithrombin III in the presence of xyloside. On the other hand, secretion of free chondroitin sulfate (and dermatan sulfate) chains into the medium was markedly increased (16-fold) in the presence of xyloside, accompanied by a smaller increase in secretion of free heparan sulfate chains. There was a good correlation between conditions with decreased antithrombin III binding and an inhibition of the endothelial cell-mediated acceleration of thrombin inactivation by antithrombin III. These results suggest that beta-D-xyloside caused a dose-dependent decrease in production as well as some subtle structural alterations of cell-surface-associated heparan sulfate, which could serve as binding sites for antithrombin III on the endothelial cells and mediate enhancing the anticoagulant activity of this protein. This system may offer a potentially useful model to investigate the possible mechanisms responsible for the development of a procoagulant state involving these endothelial macromolecules.

Animals↗

PubMedDate not supplied

Age-related changes of baroreflex function, plasma norepinephrine, and blood pressure.

Interrelationships between age, baroreflex sensitivity, plasma norepinephrine levels, and systolic blood pressure were assessed in a group of 54 normal subjects ranging in age from 14 to 77 years. Baroreflex sensitivity was measured by the change in R-R intervals per unit change in systolic blood pressure during phase 4 of the Valsalva maneuver. All correlations among these four variables were statistically significant (p less than 0.05 or 0.01). To investigate possible causal relationships between age-related changes of baroreflex sensitivity, plasma norepinephrine levels, and blood pressure, partial correlative analysis was then performed. After the effect of age was eliminated, plasma norepinephrine levels were found to be related positively to blood pressure (r = 0.29, p less than 0.05) and negatively to baroreflex sensitivity (r = -0.34, p less than 0.05). The increase in plasma norepinephrine levels could be causally related to the elevation of blood pressure, as plasma norepinephrine levels could provide an index of sympathetic activity. Furthermore, baroreflex sensitivity was found to be negatively related to age (r = -0.44, p less than 0.01) independent of plasma norepinephrine levels, whereas plasma norepinephrine levels were no longer related to age (r = 0.10) after adjusting for the effect of baroreflex sensitivity. This finding suggests that an increase in plasma norepinephrine levels with age could be mediated by the age-related change of baroreflex sensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMedDate not supplied

Comparative clinical study of cefcapene pivoxil and cefteram pivoxil in chronic respiratory tract infections by a double-blind method.

In a double-blind study, the efficacy and safety of the novel cephem antibiotic cefcapene pivoxil (CFPN-PI; 450 mg/day) was compared with cefteram pivoxil (CFTM-PI; 600 mg/day) in 171 patients with chronic respiratory tract infections. There was no significant difference between the clinical efficacy of the two drugs (80.2% for CFPN-PI versus 78.9% for CFTM-PI). There was no significant difference in the rate of elimination of the causative bacteria (60.5% for CFPN-PI versus 65.9% for CFTM-PI). Side-effects were observed in 6.0% of patients treated with CFPN-PI compared with 6.4% of patients treated with CFTM-PI. There were no significant differences in incidence of abnormal laboratory findings following treatment with the two drugs (13.9% for each), and none of the side-effects was severe. We conclude that CFPN-PI (450 mg/day) was as effective and as well tolerated as CFTM-PI (600 mg/day) in the treatment of chronic respiratory tract infections.

Adult↗

PubMedDate not supplied

[Trace analysis of biological substances by high-performance liquid chromatography with electrochemical detection].

High-performance liquid chromatography (HPLC) with electrochemical detection has been developed for the trace analysis of electrochemically active substances in biological fluids such as catecholamines. The recent development of this system, both instruments and application, has been reviewed. The principle of instrument and newly developed electrode for electrochemical detector have been described at the first section. Series electrodes, especially with coulometric detection, gave much higher selectivity to the analysis of biological substances. The application of HPLC with electrochemical detection to the determination of estrogens in biological fluids clarified the metabolic pathway of catechol estrogens. The applicability to the determination of vitamin D3 and related compounds has been also suggested. For the purpose of extending the applicability of HPLC with electrochemical detection to electro-inactive compounds, pre- and post-column labeling methods have been developed. Pre-column derivatization reagents possessing ferrocene as an electrophore provided a selective and sensitive response to the detector, because of their high-reversibility and low applied potential in the redox reaction. Post-column reaction by using immobilized enzyme reactor has been widely used for the determination of acetylcholine and choline in biological fluids.

Catecholamines↗

PubMedDate not supplied

Two cases of Pneumocystis carinii pneumonia occurred in human immunodeficiency virus infected patients: supplemental treatment with aerosolised pentamidine isethionate.

Two cases of Pneumocystis carinii pneumonia occurred in human immunodeficiency virus infected patients who were diagnosed by the aspiration-lung-biopsy. They were treated with 4 mg/kg of pentamidine isethionate intravenously administered followed by pentamidine aerosol inhalation. Although clinical and laboratory findings were improved by the fifth or seventh day of intravenous therapy, substantial leukocytopenia, from 3,000/cmm to 600/cmm and from 2,700/cmm to 1,000/cmm, occurred. At this point, the method of pentamidine administration was switched to inhalation. Pentamidine 600 mg in 30 ml distilled water was aerosolised using ultrasonic nebuliser and exposed for a 30-minute period once daily. In both cases, chest x-rays showed improvements: The disappearance of P. carinii were obtained in two weeks. Mild coughing was the sole adverse reaction encountered during the course of aerosol inhalation.

Administration, Inhalation↗

PubMedDate not supplied

Three cases of acquired immunodeficiency syndrome complicated with toxic epidermal necrolysis.

Co-trimoxazole (trimethoprim-sulfamethoxazole) and pyrimethamine-sulfadoxine have been recommended for treatment and prophylaxis, respectively, of Pneumocystis carinii pneumonia (PCP). However, toxic epidermal necrolysis (TEN) occurred in three of four patients with acquired immunodeficiency syndrome (AIDS) during the course of treatment or prophylaxis of PCP with these agents. On the other hand, 14 patients with PCP treated with pentamidine never developed TEN. Because the incidence of adverse skin reactions is higher among patients with AIDS than those without AIDS, and TEN is a severe, potentially fatal skin reaction, sulfonamide-containing drugs should be given cautiously to patients with AIDS.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

[Silent lacunes in the elderly Parkinson's disease correlated with ambulatory blood pressure].

Lacunes on brain MRI, causal blood pressure, 24-hour ambulatory blood pressure and common carotid blood flow measured by the doppler method were studied in 31 elderly patients with Parkinson's disease (mean age 67.5 +/- 7.3 years). Nineteen patients with Parkinson's disease (61%) had at least one lacune. Patients with lacunes (P(+)) were significantly higher in age than patients without lacune (P(-)). The difference of casual blood pressure between patients in the two groups was not significant. On the other hand, the average of ambulatory blood pressure measurements during a 24-hour period was significantly higher in the P(+) group than in the P(-) group. The average of carotid blood flow was also significantly lower in the P(+) group than in the P(-) group, however, after adjustment for age, the difference between them became insignificant. In conclusion, the incidence of silent lacunes on brain MRI was fairly common in elderly patients with Parkinson's disease. A high average 24-hour ambulatory blood pressure was suggested to be one of the risk factors of lacunar stroke in elderly cases of Parkinson's disease. The concept of "combine type" in Parkinsonism was supposed to be suitable as well as in senile dementia of Alzheimer type.

Aged↗

PubMedDate not supplied

Resection of peritoneal metastases from hepatocellular carcinoma.

BACKGROUND/AIMS: To evaluate whether resection of peritoneal metastases arising from hepatocellular carcinoma (HCC) has a role to play in the management of the disease. METHODOLOGY: Resections of peritoneal metastases from HCC were performed in 6 patients. The survival of the patients was evaluated in relation to feature of primary liver tumor, number of peritoneal metastases and period between hepatectomy and resection of peritoneal metastases. RESULTS: Two patients had peritoneal metastases at the time of hepatectomy for HCC, their resection being carried out synchronously. In the other 4 patients, peritoneal metastases became evident between 6 and 34 months (mean: 18) after hepatectomy; resection was performed at the time of presentation of the metastases. Patient survival after resection of the peritoneal metastases ranged from 3-31 months. The 4 patients who survived for more than 1 year had the following features: 1) a small number of metastatic nodules (= or < 4); 2) low alpha-fetoprotein (AFP) values (mean: 205 ng/ml); and, (3) metachronous occurrence of the peritoneal metastases. CONCLUSIONS: Resection of peritoneal metastases arising from HCC may be of value in improving patient survival.

Aged↗