Search PubMed⌕ Search

Biomedical subjects

M Kojima

Publications and source records attributed to M Kojima.

At least 361 records · Page 20Linked to original sources
PubMed1996

Comparative analysis of prostate specific antigen and its indexes in the detection of prostate cancer.

PURPOSE: Prostate specific antigen (PSA) density and age referenced PSA have been proposed in an attempt to improve the power of PSA in the detection of early prostate cancer. Reported results have been controversial and disappointing. Because the association of gland volume with PSA is stronger than that of age we developed a new index, volume referenced PSA, and compared it to PSA density and other indexes. MATERIALS AND METHODS: Volume referenced PSA was developed from a control group of 408 men without clinical evidence of prostate cancer using a standardized Z score. A retrospective analysis was performed comparing PSA and all its indexes in 580 men who underwent prostate biopsy. In addition to overall analysis, PSA and its indexes were evaluated with receiver operating characteristic curves by age and volume subcategories. RESULTS: Cancer was identified in 35% of the 580 men. The number of missed cancers using established thresholds significantly favored volume referenced PSA clinically and statistically compared to all other indexes but it was equivalent to PSA alone clinically. Age referenced PSA prevented more biopsies from being done than did volume referenced PSA (39% versus 31%) but resulted in the diagnosis of 48% fewer cancers. Receiver operating characteristic curve analysis demonstrated a significantly better performance for volume referenced PSA and PSA density compared to PSA alone and age referenced PSA. CONCLUSIONS: Volume based PSA indexes are superior to PSA and age referenced PSA statistically. However, clinically volume referenced PSA is comparable to PSA, and both are superior to age referenced PSA and PSA density in the detection of prostate cancer.

Adult↗
PubMed1996

Cold activation of complement in sera from patients with persistent hepatitis C virus infection on interferon therapy.

The loss of haemolytic activity in sera during storage at low temperature (the cold activation of complement) was observed in 136 of 184 (74%) patients with chronic liver disease associated with hepatitis C virus (HCV) infection. This was more frequent than observed in the three of 40 (8%) patients with chronic hepatitis B (P < 0.001) or none in 43 normal controls (P < 0.001). Of 103 patients with chronic hepatitis C who had completed a full course of recombinant interferon-alpha 2a therapy (total dose: 516 x 10(6) U), 40 responded completely and 21 responded partially, as judged by the normalization or decrease of alanine aminotransferase levels 6 months after the completion of therapy; 42 patients did not respond at all. The cold activation of complement persisted in five (13%) complete responders, less often than in 33 (79%) non-responders (P < 0.001). At the completion of interferon therapy, the cold activation of complement persisted in 12 of 54 patients despite the normalization of alanine aminotransferase. Spontaneous exacerbation of hepatitis occurred in seven of 12 (58%) patients with cold activation, which was more frequent than in the four of 42 patients (10%) without it (P < 0.01). The cold activation of complement disappeared along with the loss of HCV-RNA in five of six responders during the 6 month period after the completion of interferon therapy, while both cold activation and HCV-RNA persisted in all eight non-responders. These results indicate that the cold activation of complement may be useful as a marker of HCV viraemia for monitoring the response to interferon in patients with HCV infection.

Adult↗
PubMed1996

Focal nodular hyperplasia in an adolescent with glycogen storage disease type I with mesocaval shunt operation in childhood: a case report and review of the literature.

As patients with glycogen storage disease type I survive longer, cases with hepatic tumor have been increasingly documented. A 16 year old boy with glycogen storage disease type I was evaluated for multiple liver tumors. He was diagnosed on clinical features at 9 months of age and underwent a mesocaval shunt operation at 5 years of age. The biopsy of one of the masses showed focal nodular hyperplasia. This is uncommon in patients with glycogen storage disease type I, compared to those with adenoma or malignant hepatic tumor. The association of a portacaval shunt with focal nodular hyperplasia is significant compared to other tumors. An environment of high estrogen concentration or sex hormone binding globulin accompanied by shunt operation may cause focal nodular hyperplasia to develop in the liver of patients with glycogen storage disease type I.

Adolescent↗
PubMed1996

Imprint cytology of cat scratch disease. A report of eight cases.

The cytologic features of cat scratch disease (CSD) from eight cases in imprint smears are presented. All patients were clinicopathologically diagnosed with CSD as follows: 1) a history of animal exposure was recorded 2 to 4 weeks before lymphadenopathy; 2) the disease occurred in the autumn and winter months; 3) a characteristic histopathology in the biopsied lymph node specimens was observed; and 4) Warthin-Starry silver stain-positive bacteria were detected in four of the seven cases examined. The characteristic cytologic finding was the presence of confluent epithelioid cells with nearby and central scattering of neutrophils against a background of polymorphic inflammatory cells. Furthermore, a varying number of medium-sized to large lymphoid cells with an appearance suggestive of monocytoid B lymphocytes (MBLs) were noted to be associated with the epithelioid cells. These cytologic findings closely paralleled the histologic patterns of epithelioid cell granulomas, with and without MBLs, which we have previously reported are probably associated with the disease.

Adult↗
PubMed1996

UV-b-induced cataract model in brown-Norway rat eyes combined with preadministration of buthionine sulfoximine.

In order to develop a more adequate ultraviolet (UV)-induced cataract model, a combination of l-buthionine sulfoximine (BSO) treatment was applied to experimental animals. A single administration of BSO 4 mmol/kg caused reduced glutathione concentration until experimental day 8. In the 0.067-J/cm2 UV-B irradiation experiment, the light-scattering intensity of the anterior lens cortex of the combination group was significantly higher than that of the other groups during the second week after irradiation commenced. After the fourth experimental week, however, there was no significant difference between the group treated by UV-B alone and the combination group. In the 0.2-J/cm2 UV-B irradiation experiment, anterior polar cataract was seen in the group receiving UV-B alone, as already reported, 6 weeks after starting UV irradiation. Meanwhile, in the combination group, shallow cortical opacity was seen at 26 weeks after the start of experiment in the deeper lenticular layer which was separated from the anterior subcapsular opacity. This anterior shallow cortical opacity seemed to move towards the nuclear region during the time course of the experiment. The results of this experiment suggested that the BSO treatment accelerated cataractogenesis through additional UV-B irradiation. Although more experiments are needed, this model is useful in investigating the connection between UV-B and other cocataractogenic factors in age-related cataract in humans.

Animals↗
PubMed1996

Inhibition of steroid-induced cataract in rat eyes by administration of vitamin-E ophthalmic solution.

The efficacy of a vitamin-E (VE) ophthalmic solution was evaluated on a newly developed rat steroid-induced cataract model. Brown Norway rats irradiated with 2 Gy X-ray, right eyes only, were divided into 5 groups: the control group; 2 steroid (1 mg/kg/day)-treated groups with topic (Top) and systemic (Sys) administration, and 2 VE-treated groups, 1 with the same treatment as the Top group with the addition of 5% VE twice a day (Top + VE) and 1 with the same treatment as the Sys group with 5% VE twice a day (SYS + VE). The lens changes were documented with a Scheimpflug camera and changes in light scattering were evaluated quantitatively. The VE-treated groups (Top + VE and Sys + VE) showed a significant inhibition of the increase in the opaque area compared with each of the non-VE-treated groups. The VE ophthalmic solution was strong enough to prevent steroid-induced cataract in rats.

Animals↗
PubMed1996

A new steroid-induced cataract model in the rat: long-term prednisolone applications with a minimum of X-irradiation.

In order to induce experimental steroid cataracts in rat eyes similar morphologically to those seen in human eyes, prednisolone acetate was administered either topically or systemically for 12 months with a low dose of X-irradiation as a cocataractogenic factor. Twenty-seven Brown-Norway rats were randomly divided into a control group (group I) with no steroid administration; an eyedrop group (group II) with a daily 1% prednisolone acetate instillation of a total volume of 1.0 mg/kg in both eyes, and a systemic group (group III) with a daily intramuscular injection of 0.8-1.0 mg/kg prednisolone acetate. The right eyes of animals in each group were X-irradiated with a single dose of 2 Gy. Topical and systemic steroid administrations started 2 weeks after X-irradiation. Anterior segment changes were documented with a slitlamp microscope and an anterior eye segment analysis system once a month. Body weight and blood glucose levels were examined every week and every 2 weeks, respectively. The mortality rates in groups I, II and III were 0, 11 (1/9) and 25% (3/12), respectively. The both lenses in group I showed a gradual increase in light-scattering intensity in the nuclear and supranuclear regions over time. Initial lens changes in both steroid-treated groups were Y-suture dissociation and a slight increase in light-scattering intensity in the posterior supranuclear region 3 months after prednisolone administration. Opacification of the anterior shallow cortex and the posterior subcapsular layer was observed after 10 months. X-irradiated eyes showed more prominent lens opacification as compared with nonirradiated eyes after 10 months in both group II and group III. Either topical or systemic administrations of prednisolone acetate over a long term successfully induced morphological lenticular changes in the rat similar to those found in human steroid-induced cataracts. A low dose of X-irradiation effectively accelerated opacification as a cocataractogenic risk. This new model will allow future investigation of steroid cataracts.

Animals↗
PubMed1996

Three-dimensional volume visualization of the in vivo human ocular lens showing localization of the cataract.

An in vivo human lens containing a cataract has been visualized by volume rendering a transformed series of 60 rotated Scheimpflug digital images. The data set was obtained by rotating the Scheimpflug camera about the optic axis of the lens in 3-degree increments. The set of 60 Scheimpflug digital images were mathematically transformed into a new data set in which the images are oriented perpendicular to the optic axis of the eye. The transformed set of optical sections were first aligned to correct for eye movements during the data collection process, then rendered into a three-dimensional volume reconstruction with volume-rendering computer graphics techniques. The viewpoint and the transparency of the volume rendered in vivo human lens were varied in order to observe volume opacities in various regions of the lens. To help visualize lens opacities, the intensity of light scattering was pseudocolor-coded as an integral part of the three-dimensional volume rendering. Three-dimensional, pseudocolored volume rendering of the in vivo human ocular lens represents a new technique to visualize in vivo human cataracts.

Aged↗
PubMed1996

Distributional change of alpha-tocopherol in the rat lens with age.

Concentration of alpha-tocopherol (alpha-Toc.) in the rat lens (1, 4 and 12 months old) was determined in single lenticular layers using gas chromatography and mass spectrometry. The highest concentration of alpha-Toc. in lens was found in the nucleus, followed by the deeper anterior and deeper posterior cortices, the shallow anterior and shallow posterior cortices, and the equatorial region. The topographic alpha-Toc. distribution in the lens did not differ between lenses of 1-, 4- and 12-month-old rats. A significant decrease of alpha-Toc. concentration was seen in lenses of 4- and 12-month-old rats compared to those 1 month old. Concentration and distribution in 4- and 12-month-old rat lenses were almost the same. The concentration of alpha-Toc. in the lens changes in relation to age.

Aging↗
PubMed1996

Benidipine improves endothelial function in renal resistance arteries of hypertensive rats.

We studied the effects of long-term antihypertensive treatment on endothelial function in renal resistance arteries from spontaneously hypertensive rats (SHR). Wistar-Kyoto rats (WKY) were used as a normotensive reference. Adult SHR were treated with benidipine (a calcium antagonist) or ecarazine (a vasodilator) for 10 weeks; the drugs caused similar reductions in blood pressure. Changes in isometric tension of rings prepared from the third-order branches of the renal arteries were recorded. Endothelium-dependent relaxations induced by acetylcholine in rings contracted with norepinephrine were smaller in SHR than in WKY. The impaired relaxation was improved by benidipine treatment, but ecarazine had no significant effect. In vitro treatment with meclofenamic acid, a cyclooxygenase inhibitor, did not alter the differences in the relaxations. In the presence of meclofenamic acid, N omega-nitro-L-arginine methyl ester slightly reduced the relaxations; the relaxation was smaller in SHR than in WKY and was not affected by benidipine treatment. In rings contracted with 40 mmol/L. KCI, the relaxations induced by acetylcholine in the presence of meclofenamic acid were smaller than those in rings contracted with norepinephrine. The relaxation was smaller in SHR than in WKY but was normalized by benidipine treatment. Thus, acetylcholine relaxes rat renal resistance arteries by releasing nitric oxide and endothelium-derived hyperpolarizing factor from the endothelium, which is impaired in SHR. Long-term benidipine treatment improves the impaired relaxation in SHR by enhancing nitric oxide-mediated relaxation.

Acetylcholine↗
PubMed1996

Endothelial modulation of contractile responses in arteries from hypertensive rats.

The endothelium plays an important role in the circulation by modulating contractile responses of vascular smooth muscle. We designed this study to investigate the alterations of endothelial modulation in hypertension. Rings of femoral arteries were prepared from Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR), and changes in isometric tension were recorded. In rings with endothelium, norepinephrine (in either the presence or absence of yohimbine) evoked concentration-dependent contractions. Endothelium removal markedly enhanced the contraction; both the maximal response and sensitivity were increased, and these responses were less pronounced in SHR than WKY. In contrast to norepinephrine-induced contractions, the enhancement of prostaglandin F2 alpha-or serotonin-induced contractions after endothelium removal was small and comparable in WKY and SHR; sensitivity was increased, but the maximal response was not. N omega-Nitro-L-arginine methyl ester enhanced the contractions induced by these agonists in arteries with but not without endothelium and thereby abolished the enhancement of the contractions after endothelium removal. Thus, the endothelium plays an inhibitory role against contractions in rat femoral arteries by releasing nitric oxide, but the characteristics of the endothelial inhibition are not identical against various types of contractions. The negative endothelial modulation is more pronounced during alpha 1-adrenoceptor-mediated contractions than during contractions mediated by other receptors. The inhibitory role of the endothelium against alpha 1-adrenoceptor agonist-induced but not serotonin- or prostaglandin F2 alpha-induced contraction is impaired in hypertension.

Adrenergic alpha-Agonists↗
PubMed1996

Dopamine receptor affinities in vitro and stereotypic activities in vivo of cabergoline in rats.

An ergot alkaloid derivative, cabergoline, and its metabolites were investigated for their affinities for dopamine D1 and D2 receptors in rat striatum in vitro in comparison with those of bromocriptine and pergolide. The affinity for D1 receptors was in the following order: pergolide > des-dimethylaminopropyl cabergoline (FCE21904) > cabergoline > or = bromocriptine > or = des-methyl cabergoline (FCE27395) > or = des-ethylcarbamoyl cabergoline (FCE21590). From the effects of GTP on these affinities for the D1 receptor, cabergoline, some of its metabolites, and pergolide were characterized as agonists in contrast to bromocriptine which was classified as an antagonist. The affinity for D2 receptors was ranked as follows: pergolide > or = cabergoline > or = FCE27395 > or = FCE21904 > bromocriptine > FCE21590 > carboxylic acid-type derivative of cabergoline (FCE21589). The affinity of each compound for the D2 receptor was much higher than that for the D1 receptor. The selectivity of cabergoline for D2 receptor was higher than those of bromocriptine and pergolide. Furthermore, these ergot alkaloids were investigated for eliciting stereotypy after subcutaneous administration to normal rats. Pergolide potently induced stereotypy at doses of 0.5 and 1.0 mg/kg, cabergoline slightly induced it only at a high dose of 2.0 mg/kg, whereas bromocriptine did not induce it at any of the doses tested, 10-40 mg/kg. These results suggest that pharmacological properties of cabergoline for the D1 and D2 receptors differ from those of bromocriptine and pergolide.

Animals↗
PubMed1996

Effect of cabergoline, a long-acting dopamine D2 agonist, on reserpine-treated rodents.

We studied the characterization of cabergoline, a new ergot alkaloid derivative and a selective dopamine D2 receptor agonist, in comparison to bromocriptine and pergolide in reserpine-treated rodents. Cabergoline (0.25-1.0 mg/kg, s.c.) improved dose-dependently the reserpine-induced akinesia that was assessed on the locomotor activity, and the efficacy lasted longer than those of bromocriptine (1.25-5.0 mg/kg, s.c.) or pergolide (0.0625-0.5 mg/kg s.c.). Cabergoline (ED50 = 1.10 mg/kg, at 4 h after the administration of drugs) also reversed catalepsy, the failure to correct an externally imposed posture, and its efficacy was stronger and longer than bromocriptine (ED50 = 4.65 mg/kg, at 4 h). Further, reserpine-induced rigidity was improved equally by cabergoline (0.125-1.0 mg/kg, i.v) and bromocriptine (1.0 mg/kg, i.v.). When cabergoline was administered together with 3(3,4-dihydroxyphenyl)-L-alanine (L-DOPA), the effects were additive. Our results indicate that the long-lasting effects of cabergoline could be beneficial for treating Parkinson's disease.

Animals↗
PubMed1996

Enzymatic synthesis of 4-O-beta-D-galactopyranosyl-moranoline and 3-O-beta-D-galactopyranosyl-moranoline by using beta-galactosidase from Bacillus circulans.

A transgalactosylation reaction from lactose to moranoline (1-deoxynojirimycin) was accomplished by using beta-galactosidase [EC 3.2.1.23] from Bacillus circulans. The enzyme formed 3-O-beta-D-galactopyranosyl-moranoline and 4-O-beta-D-galactopyranosyl-moranoline as major products, together with 2-O-beta-D-galactopyranosyl-moranoline and 6-O-beta-D-galactopyranosyl-moranoline as minor ones.

1-Deoxynojirimycin↗
PubMed1996

[Mutagenicity studies of prulifloxacin (NM441) and the active metabolite (NM394)].

The mutagenicity of prulifloxacin, a new antibacterial agent, was investigated by the reverse mutation test in bacteria, the chromosomal aberration test in cultured cells, and the micronucleus test in mice. In addition, NM394, an active metabolite of prulifloxacin, was examined for mutagenicity in the chromosomal aberration test in cultured cells. The reverse mutation test was performed at dose range of 0.0078-0.25 micrograms/plate using Salmonella typhimurium strains (TA100, TA1535, TA98, and TA1537), and Escherichia coli (WP2uvrA). Prulifloxacin did not increase revertant colonies significantly in any of the test strains with or without metabolic activation system (S9 mix). The chromosomal aberration tests were carried out in cultured Chinese hamster lung cells (CHL/IU). Prulifloxacin increased aberrant cells without S9 mix, and NM394 also induced chromosomal aberrations. In human lymphocytes, no significant increases of the frequencies of cells with chromosomal aberrations were observed at dose range of 5-320 micrograms/ml with or without S9 mix. The micronucleus test was conducted at doses of 625-5000 mg/kg in the bone marrow cells of Slc : ddY male mice. There were no significant increases in the frequencies of micronucleated polychromatic erythrocytes.

Animals↗
PubMed1996

Epidemiology of diseases of unknown etiology, specified as "intractable diseases".

In Japan, epidemiological studies on intractable diseases have been undertaken and greatly promoted for more than 20 years by the Research Committee on Epidemiology of Intractable Diseases, with the financial supports from the Ministry of Health and Welfare of Japan. In this paper, chronological history of development of the Research Committee and some scientific accomplishments by the recent Research Committee (1993-1995) were summarized, mainly focusing on descriptive, analytical and other epidemiological studies. Hoped is that the readers are to be acquainted with the recent research activities by the Research Committee and seek for possible international collaborations in epidemiological studies on intractable diseases.

Epidemiologic Methods↗
PubMed1996

Visual acuity disturbance in subjects over 50 years of age in a population-based cataract survey.

Visual acuity is still an essential examination item in cataract epidemiological studies, even though this parameter lacks objective reliability. A population-based epidemiological study was conducted in a rural area of Japan to find out the relationship between visual acuity levels and cataracts, the types of gradings of which were evaluated by an objectively reliable method through lens images, and to serve as a sample for researchers who perform epidemiological studies on cataract but lack the latest methodology. 863 participants above 50 years of age were examined and those previously diagnosed with ocular diseases which affect visual acuity were excluded from the analysis as much as possible. The mean visual acuity (LogMAR) in subjects in their 50s, 60s, 70s and over 80 years of age was 1.1, 1.0, 0.7 and 0.4, respectively. Both the mean and the distribution of visual acuity showed a statistically significant relationship to ageing (p < 0.01, p < 0.01). Both age and cataract grading showed a statistically significant relationship to visual acuity (p < 0.01), but there was no significant interaction effect between these two variables upon visual acuity. Visual acuity worsened remarkably with ageing in the eyes with grade III, whereas that of eyes with grades I and II remained fairly stable at a level of 0.7-1.0, except for those above 80 years of age. A fairly good visual acuity of 1.0, 0.8 and 0.7 remained in the eyes with pure cortical cataract of grades I, II and III, respectively, whereas those with mixed type cataract were 0.9, 0.6 and 0.3, respectively.

Aged↗