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Biomedical subjects

S Aoki

Publications and source records attributed to S Aoki.

At least 703 records · Page 39Linked to original sources
PubMedDate not supplied

Anticholinergic action of Swertia japonica and an active constituent.

The anticholinergic action of Swertia japonica, used in Japan as a bitter stomachic, was examined using in vivo experiments in rats in order to substantiate the presence or absence of antispasmodic properties. The methanol extract of Swertia japonica was found to be an effective anticholinergic given orally. Fractionation and purification of the methanol extract through column chromatography revealed that swertiamarin, found in the methanol extract in amounts of about 30%, was an active constituent with an anticholinergic action.

Animals↗
PubMedDate not supplied

Three-dimensional brain visualization for metachromatic leukodystrophy.

The basic understanding of many neurogenetic diseases requires study of the clinical, biochemical, and pathological aspects. To study the pathological aspects, the organs affected by the disease must be observed. We have used volume visualization techniques to create three-dimensional (3D) brain images of a patient with late infantile metachromatic leukodystrophy (MLD). The 3D brain images showed clearly, stereographically, and non-invasively the intracerebral lesion. This lesion, which indicated hyperintensity in magnetic resonance (MR) images, extended throughout the periventricular white matter. The 3D brain images are provided to integrate information. Volumetric ray-casting was useful in obtaining directly images of the entire brain and in allowing an intuitive understanding of the extension of the lesion in three dimensions and of the extent of the defects in the MLD brain. Isosurfacing facilitated a clear extraction of the lesion located by volumetric ray-casting. Each technique used in this study played a role in visualization and their use was complementary. 3D brain images will promote morphological investigation of neurogenetic diseases.

Brain↗
PubMedDate not supplied

Possible prognostic markers in conjunctival dysplasia and squamous cell carcinoma.

Conjunctival squamous cell carcinoma (SCC) can develop from carcinoma in situ or severe dysplasia known as conjunctival intraepithelial neoplasia (CIN). Conjunctival intraepithelial neoplasia and SCC are histopathologically well-defined conditions. However, it is difficult to determine the grading of dysplasia by clinical morphologic findings. Recently, proliferating cell nuclear antigen (PCNA) immunostaining, p53 immunostaining, and argyrophilic nucleolar organizer regions (AgNORs) staining have been established as valuable means of studying the biologic behavior of malignant cells. In the present study, these three staining techniques were used to examine histologic preparations of three conjunctival dysplasia and one SCC lesion. Five conjunctival tumor samples were obtained from four patients between July 1993 and October 1995. Following formalin fixation and embedding in paraffin, PCNA, and p53 immunostaining and AgNORs staining was performed with all tissue specimens. The PCNA-positive rate was the highest in SCC, followed by severe dysplasia and mild dysplasia. The p53-positive rate was the highest in severe dysplasia, followed by mild dysplasia, and negative in SCC. The AgNORs-count increased as malignancy advanced. These staining methods, which are markers for proliferative potency and cell differentiation, will be useful for early detection of changes in malignancy and will aid in decisions on treatment and prognosis.

Aged↗
PubMedDate not supplied

Presynaptic effects of botulinum toxin type A on the neuronally evoked response of albino and pigmented rabbit iris sphincter and dilator muscles.

PURPOSE: To investigate the effects of botulinum toxin type A (botulinum A toxin) on the autonomic and other nonadrenergic, noncholinergic nerve terminals. METHODS: The effects of botulinum A toxin on twitch contractions evoked by electrical field stimulation (EFS) were studied in isolated albino and pigmented rabbit iris sphincter and dilator muscles using the isometric tension recording method. RESULTS: Botulinum A toxin inhibited the fast cholinergic and slow substance P-ergic component of the contraction evoked by EFS in the rabbit iris sphincter muscle without affecting the response to carbachol and substance P. These inhibitory effects were more marked in the albino rabbit than in the pigmented rabbit. Botulinum A toxin (150 nmol/L) did not affect the twitch contraction evoked by EFS in the rabbit iris dilator muscle. CONCLUSIONS: These data indicated that botulinum A toxin may inhibit not only the acetylcholine release in the cholinergic nerve terminals, but also substance P release from the trigeminal nerve terminals of the rabbit iris sphincter muscle. However, the neurotoxin has little effect on the adrenergic nerve terminals of the rabbit iris dilator muscle. Furthermore, the botulinum A toxin binding to the pigment melanin appears to influence the response quantitatively in the two types of irides.

Albinism↗
PubMedDate not supplied

Effects of transfection of p210bcr-abl and bcr-v-abl into the factor-dependent human leukemia cell line HSM-911.

In order to clarify the action of the bcr-abl, a growth factor dependent human leukemic cell line (HSM-911) was transfected with p210bcr-abl or bcr-v-abl by electroporation. The cells transfected with bcr-v-abl, but not the cells transfected with p210bcr-abl, became growth factor independent. Some clones of the cells transfected with p210bcr-abl demonstrated cellular maturation (nuclear segmentation, becoming positive for naphthol ASD chloroacetate esterase, the disappearance of CD34 expression and the appearance of glycophorin A and CD10 expression). Moreover, these clones transfected with p210bcr-abl demonstrated apoptosis (increased expression of Fas and DNA ladder formation suggesting apoptotic DNA fragmentation). These findings demonstrated the different actions of p210 bcr-abl and bcr-v-abl, the former of which gave the cells the characteristics of maturation like the cells from chronic myelogenous leukemia, and the latter of which rendered the cells grow autonomously.

Apoptosis↗
PubMedDate not supplied

Chemistry of zinc(II) fluorophore sensors.

The biological role of the zinc(II) ion has been recognized in DNA and RNA synthesis, apoptosis, gene expression, or protein structure and function. Therefore, development of useful zinc(II) sensors has recently been attracting much interest. Chemistry for selective and efficient detection of trace Zn2+ is a central issue. Recently, various types of zinc-fluorophores are emerging, comprising bio-inspired aromatic sulfonamide derivatives, zinc-finger peptides attached to fluorescent dyes, or fluorophore-pendant macrocyclic polyamines. The chemical principles, properties and limitations of these Zn2+-fluorophores are discussed.

Amino Acid Sequence↗
PubMedDate not supplied

Ultrasonographic assessment of fetal and neonatal spleen.

To assess the growth and function of the fetal spleen, ultrasonographic examinations were performed on 229 normal fetuses, ranging from 20 to 41 weeks, menstrual age. Curvilinear relationships were found between the menstrual age and splenic length (R2 = 92.7%), circumference (R2 = 93.9%), and area (R2 = 95.2%). A normal range of splenic length, circumference, and area measurements for estimating the growth of the fetal spleen during normal pregnancy was generated. Splenic parameter values just after delivery were significantly lower than those measured within 7 days before delivery, and returned to former sizes 24 hours later, in both vaginal delivery and cesarean section groups. Splenic parameter values in the vaginal delivery group were also significantly lower than those in the cesarean section group, just after delivery. Moreover, neonatal splenic length showed negative correlations with lactate dehydrogenase (p < 0.001) and glutamic oxaloacetic transaminase (p < 0.05) in the umbilical venous blood, respectively. These results provide a foundation for the evaluation of fetal splenic growth and function during pregnancy and the early neonatal period.

Anthropometry↗
PubMedDate not supplied

Respiratory health associated with exposure to automobile exhaust. I. Results of cross-sectional studies in 1979, 1982, and 1983.

Three cross-sectional studies were conducted in an effort to investigate the effect of automobile exhaust on respiratory symptoms. Female adult subjects were selected from residents who lived near roadways that were subjected to very heavy traffic. A standard questionnaire was administered to approximately 5,000 people. Distances of the residences from the roadside were adopted as an index of exposure to automobile exhaust. The estimated odds ratios for chronic cough, chronic phlegm, chronic wheeze, shortness of breath, and chest cold with phlegm, relative to distance from the roadside--adjusted by age, smoking status, years at residence, occupation, and type of home heating-ranged from 0.76 to 2.75. The 95% confidence limits of the odds ratios for chronic cough and chronic phlegm excluded or approached 1.00 in each of the studies. This suggests that exposure to automobile exhaust may be associated with an increased risk of certain respiratory symptoms.

Adult↗
PubMedDate not supplied

Experimental basis for use of fluconazole for preventive or early treatment of disseminated candidiasis in granulocytopenic hosts.

To determine the potential for the use of fluconazole for prevention and treatment of disseminated candidiasis in granulocytopenic patients, we investigated its activity and pharmacokinetics in models of acute, subacute, and chronic forms of disseminated candidiasis in persistently granulocytopenic rabbits. Fluconazole was administered for systemic prophylaxis, early treatment, and delayed treatment. Single-dose and steady-state plasma pharmacokinetics, tissue penetration, and dose-response studies of the investigational compound were studied in subacutely infected granulocytopenic rabbits. Fluconazole was more effective when used for systemic prophylaxis or early treatment of disseminated candidiasis than for delayed treatment. Fluconazole was as effective as amphotericin B plus flucytosine in preventive and early treatment of disseminated candidiasis but was significantly less effective than amphotericin plus flucytosine in the treatment of chronic candidiasis. Dose-response studies demonstrated that the antifungal effect of fluconazole was dose- and time-dependent. Studies of the pharmacokinetics of fluconazole in rabbits demonstrated a long half-life in plasma and a large volume of distribution, properties that correspond to the attainment of high levels of penetration into tissues at multiple organ sites. We conclude that fluconazole is effective for prevention and early treatment of disseminated candidiasis in persistently granulocytopenic rabbits and that the evaluation of its use in preventive or early treatment of disseminated candidiasis in carefully designed clinical trials is warranted.

Acute Disease↗
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Diffusion property in a hamartomatous lesion of neurofibromatosis type 1.

Though diffusion-weighted MRI has been applied to various intracranial lesions, few reports had been presented about cerebral hamartomatous lesions in patients with neurofibromatosis type 1 (NF1). In this study, we report the interval changes of apparent diffusion coefficient (ADC) in a presumed hamartomatous lesion. In our case, the ADC increased slightly over a 3 year period. This diffusion property may provide specific insight into the etiology of cerebral hamartomatous lesions observed in NF1.

Brain Diseases↗
PubMedDate not supplied

Statistical analysis of symptoms and signs in pediatric patients with peptic ulcer.

It is not well known which symptoms or signs related to peptic ulcer are crucial for its diagnosis in children. In order to clarify this problem, we evaluated the sensitivity, specificity, and positive and negative predictability of 13 ulcer-related symptoms and signs. The data of 160 patients, who were suspected of having peptic ulcer and had undergone endoscopic examinations, were studied. It was significant that five symptoms, i.e., presence of pain in the epigastrium, relationship between the time of pain and that of eating, family history, vomiting, and bleeding, were frequently found in ulcer patients. There was, however, no symptom or sign that predicted by itself precisely the existence of a peptic ulcer. Thus, we computed a discriminant function by combining the data by multivariate analysis. With this score, we could predict the existence of ulcer more precisely. Finally, it was concluded that epigastric pain, food-related pain, vomiting, bleeding, and family history were crucial factors for the diagnosis of peptic ulcer in childhood and that an overall consideration of symptoms and signs was needed for the evaluation of these factors.

Adolescent↗
PubMedDate not supplied

Ataxic hemiparesis with reductions of ipsilateral cerebellar blood flow.

Regional cerebellar blood flow was measured in a patient with left-sided ataxic hemiparesis, using single-photon emission computed tomography and N-isopropyl-p-[123I]Iodoamphetamine. X-ray computed tomography revealed a small infarct in the paramedian portion of the right upper basis pontis. Blood flow was markedly reduced in the contralateral cerebellar hemisphere corresponding to the side of ataxia. The present study emphasizes the value of the three-dimensional functional imaging of the cerebellum to investigate the responsible lesion for ataxia and to study function of the cerebro-cerebellar circuits.

Aged↗
PubMedDate not supplied

Active MR tracking on a 0.2 Tesla MR imager.

An active MR tracking system was implemented on a 0.2 Tesla open MRI system. Interventional devices with receive-only microcoils at their tips were developed and investigated on the scanner. Microcoils having a diameter of about 1 mm and 20 turns were found to provide sufficient signal-to-noise ratios for stable tracking. Positional accuracy and precision were found to be acceptable under practical conditions. Simulation of MR-guided biopsy using biplane images with tracking was performed in a gelatin phantom and dog livers. Successful tracking of catheters with integrated microcoils was also demonstrated in the aorta and IVC of live dogs.

Animals↗
PubMedDate not supplied

Effect of concurrent intra-arterial infusion of platinum drugs for patients with stage III or IV uterine cervical cancer treated with radical radiation therapy.

PURPOSE: The purpose of this study was to explore the effect of concurrent intra-arterial infusion of platinum drugs in patients with stage III or IV uterine cervical cancer treated with radical radiation therapy. PATIENTS AND METHODS: Thirty-three patients with advanced (stage IIIA, 2; IIIB, 28; IVA, 3) uterine cervical squamous cell carcinoma were randomized into a concurrent intra-arterial infusion of platinum drugs with radiation therapy (IAPRT) group (18 patients) and a radiation therapy alone group (15 patients). After altering intrapelvic blood flow by embolization of the superior and inferior gluteal arteries under pelvic angiography, intra-arterial infusion of platinum drug through catheters inserted into both internal iliac arteries was performed concurrently with radiation therapy. One-shot infusion of cisplatin (100 mg/m2) twice with a 2- to 3-week interval was performed in eight patients, weekly infusion of carboplatin (100 mg/m2) via a reservoir five to six times was performed in four patients, and daily shot of cisplatin (10 mg/body) or 21 days via a reservoir was performed in six patients. Radiation therapy consisted of external-beam irradiation of 50 Gy/25 fractions/5 weeks for the whole pelvis with midline block after 30 Gy and intracavitary high-dose-rate brachytherapy using tandem and ovoids of 24 Gy/4 fractions/4 weeks to point A. RESULTS: The local complete response rate of the IAPRT group was 94% and was significantly higher than that of the radiation therapy group (67%). There were no significant differences in local response in the three drug delivery methods. Two- and 5-year overall survival rates were 54.5% and 44.4% in the IAPRT group, and 74.5% and 50.0% in the radiation therapy group, respectively. There was no significant difference between the two groups. In the IAPRT group, grade 3 or 4 acute bowel complications were seen in 33% of patients, grade 3 or 4 late bowel complications were seen 44%, and grade 3 or 4 myelosuppression was seen in 33%, and these complications were seen more in the IAPRT group than in the radiation therapy group and caused death in some patients. CONCLUSIONS: IAPRT had a better local response than radiation therapy but showed no proof of control over recurrence and had a poorer survival than radiation therapy. There were many local recurrences and distant metastases, contrary to the better first response of the IAPRT group over the radiation therapy group. Complications of the IAPRT group were very severe and made the patient's performance status and prognosis worse than in the radiation therapy group. We need to design some methods to decrease these complications to make use of the good local response acquired with IAPRT. Furthermore, we should re-examine the indication of IAPRT in patients with a large tumor because local recurrence and distant metastasis would be inevitable.

Adenocarcinoma↗
PubMedDate not supplied

Total body and hepatic clearance in rats of recombinant tissue-type plasminogen activator expressed in mouse C127 and Chinese hamster ovary cells.

The total body and hepatic clearance of two recombinant human tissue-type plasminogen activators (t-PA) produced in mouse C127 cells [t-PA(C127)] and in Chinese hamster ovary cells [t-PA(CHO)] were determined in rats. Recombinant t-PA was administered as a constant iv or intraportal venous infusion for 60 min. The plasma t-PA level over 120 min was measured by an ELISA. Whole-body pharmacokinetics were characterized in terms of the total body clearance (CLt), total volume of distribution, and mean residence time in the body. Hepatic disposition was described by the hepatic clearance (CL(hep)) and the mean hepatoportal transit time. Whereas a marked hepatic extraction was observed with both t-PAs, the estimated CL(hep) accounted for only one-half the Clt. No elimination took place in the lung, because no difference was observed between iv and intraarterial administration. Extrahepatic elimination, such as that in circulating blood, appeared to play a significant role in the disposition of t-PA in vivo. t-PA(C127) is known to possess the Gal alpha 1-3Gal epitope in its complex-type carbohydrate chains, whereas this structure is not involved in t-PA(CHO). In the presence of Bandeiraea simplicifolia lectin I isolectin B4, which is specific to the Gal alpha 1-3Gal, the Clt of t-PA(C127) was significantly decreased, whereas that of t-PA(CHO) was unchanged. These results imply that the formation of a high molecular weight complex by this carbohydrate epitope effectively reduces the rate of catabolism of t-PA in vivo.

Animals↗
PubMedDate not supplied

The micronucleus assay with mouse peripheral blood reticulocytes using acridine orange-coated slides with triethylenemelamine.

A micronucleus assay using mouse peripheral blood and supravital staining with acridine orange (AO) was validated by two laboratories on triethylenemelamine-treated mice. Dose- and time-dependent increases in micronucleated peripheral reticulocytes were observed. This new method can be used as an alternative to the conventional bone marrow micronucleus assay.

Acridine Orange↗
PubMedDate not supplied

Histological features of rheumatoid arthritis patients having antibodies to enterobacterial common antigens: correlation of antibody levels with semiquantitative histologic scores and laboratory markers.

OBJECTIVE: To ascertain whether clinically diagnosed rheumatoid arthritis (RA) patients having antibodies to enterobacterial common antigens (ECA) in synovial fluid (SF) have a histological appearance characteristic of RA synovitis. METHODS: Twenty-five RA patients for which synovial biopsy specimens were preserved, were selected from 58 patients with RA tested for antibodies to ECA in SF The synovial tissue specimens were examined histologically using a semiquantitative scoring system with quantitative counts. The correlation of anti-ECA antibody levels with total scores for synovitis and laboratory markers in three RA patient groups (markedly positive, moderately to slightly positive, and negative according to anti-ECA antibody levels) was analyzed statistically. RESULTS: Histologic examination in the markedly positive RA group (total score for synovitis, range 18-20 points) revealed typical histological features of rheumatoid synovitis. Total scores for synovitis were significantly higher in both the markedly positive and moderately to slightly positive RA groups than in the negative RA group. A comparison of anti-ECA antibody levels with total scores for synovitis revealed a strong and significant correlation. Furthermore, levels of anti-ECA antibodies were also correlated with rheumatoid factor and C-reactive protein. CONCLUSION: Clinically diagnosed RA patients having anti-ECA antibodies in SF showed typical or characteristic histological features of RA synovitis. Our data suggest that a group of RA patients with an entrobacterial etiology exists in larger groups of patients with RA which is thought to be a heterogeneous disease.

Adult↗