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Biomedical subjects

T Matsuo

Publications and source records attributed to T Matsuo.

At least 91 records · Page 5Linked to original sources
PubMed2001

Effects of photocatalytic reactions on marine plankton: titanium dioxide powder as catalyst on the body surface.

Photocatalytic effects of TiO2 powder on marine plankton were examined by the use of either brine shrimp Artemia salina or noxious red tide flagellate Chattonella antiqua as a probe. After UV (365 nm) irradiation for ca. 1 hour, A. salina stopped moving and the body surface was completely covered by TiO2 powder. Similar photoirradiation of C. antiqua, on the other hand, induced deformation of the body from spindle to round shape within 20 minutes. The deformed C. antiqua recovered to normal shapes, when the cells were kept in the same conditions but without UV irradiation for more than 40 minutes. On the prolonged UV irradiation (more than 100 minutes), however, the cells burst and came to annihilation. The photocatalytic reactions of TiO2 on the body surface are thus concluded to induce fatal damages to these microorganisms.

Animals↗
PubMed2001

Effects of prenatal rubratoxin-B exposure on behaviors of mouse offspring.

The effects of prenatal rubratoxin-B (RB) exposure on 8 behavioral parameters in JCL:ICR mice were assessed. Pregnant mice were injected intraperitoneally with 0.1 or 0.2 mg/kg/day of RB dissolved in propylene glycol water solution on days 7-9 (Group A) or 10-12 (Group B) of gestation. Controls received the vehicle similarly on days 7-12 of gestation. Before weaning, the offspring of both sexes were examined to test their the surface righting reflex (5 days of age), cliff avoidance response (6 days), negative geotaxis response (7 days), and swimming development (8, 10, and 12 days). After weaning, male animals were examined using the rotarod test (6 weeks of age), the open-field test (7 weeks), the shuttle-box-avoidance-learning test (9 weeks), and the water E-maze test (10 weeks). The preweanling offspring in the 0.2 mg/kg-B group showed significantly lower success rates and longer response times than controls in the cliff-avoidance response. In swimming development, the offspring in the 0.2 mg/kg B group had significantly lower scores than controls for swimming angle at 10 and 12 days of age. The avoidance learning of the mice in all RB-exposed A and B groups was significantly poorer than that of controls. These results indicate that prenatal exposure to RB produced a delay of early response development and impaired learning ability in the offspring of mice exposed to RB during middle pregnancy.

Animals↗
PubMed2001

Release of flexors and intrinsic muscles for finger spasticity in cerebral palsy.

Between April 1987 and March 1996, 32 deformed hands of 31 patients with cerebral palsy were treated with combined release of the flexor digitorum profundus, flexor digitorum superficialis, and intrinsic muscles. Of these 31 patients, 26 patients (27 hands) were followed up after treatment. Improvements were evaluated by the modified classification of Zancolli et al, the classification of House et al, the object handling score, and the activity of daily living score. Improvements of more than one level on an average were observed in the modified classification of Zancolli et al and the classification of House et al. The ability to grasp, pinch, and release increased with improvement of 2.5 points in the object handling score, and activities of daily living were enhanced with improvement of 2.4 points. The fine motor skills could be facilitated, and dexterity was restored in most patients.

Adolescent↗
PubMed2001

An immunohistological study on cyclooxygenase-2 in human dental pulp.

Characteristics of cyclooxygenase-2 (COX-2) expressing cells in human dental pulp were immunohistologically studied. Extirpated pulpal tissues from extracted teeth were examined to elucidate the localization and distribution of COX-2. Pulpal tissues were examined by the labeled streptavidin biotin method using specific mouse monoclonal antibodies for COX-2. Cell types of the COX-2 expressing cells were also investigated by the double stain technique using both monoclonal antibodies for CD68/macrophage and anti-COX-2. COX-2 expressing cells could be found in all of the inflamed pulps, and these cells were mostly distributed close to the area of accumulation of inflammatory cells. COX-2 was mainly expressed in fibroblasts rather than macrophages. In contrast, COX-2 expressing cells were scarcely found in the normal pulps. These findings indicate that pulpal fibroblasts, as well as macrophages, may participate in the production of prostaglandin through COX-2 expression in pulpal inflammation, and might be involved in the pathogenesis of irreversible pulpitis.

Adult↗
PubMed2001

Trehalose protects corneal epithelial cells from death by drying.

AIM: This study was designed to examine whether trehalose could protect corneal epithelial cells in culture from death by desiccation in order to test trehalose as a potential new eye drop for dry eye syndrome. METHODS: Human corneal epithelial cells in near confluent culture in wells of a 96 well multidish were preincubated for 15 minutes with 2, 20, 50, 100, or 200 mM trehalose or maltose in phosphate buffered saline (PBS), PBS alone, or three kinds of commercially available artificial tear substitutes (one with borate buffered saline and the other two containing either hydroxyethylcellulose or hyaluronan). The medium was aspirated completely and cells were left dry for 30 minutes at room temperature in room humidity. Live cells and dead cells were visualised by fluorescent dyes and counted for statistical analysis. RESULTS: The percentage of dead corneal epithelial cells after desiccation was significantly lower in preincubation with 50, 100, and 200 mM trehalose, compared with preincubation with PBS alone (p < 0.0001, Kruskal-Wallis test, and p < 0.05, Tukey-Kramer test). Trehalose at the concentration of 20 mM or lower, maltose at any concentrations, and commercially available artificial tear substitutes did not protect corneal epithelial cells from death by desiccation. CONCLUSIONS: Trehalose at 50, 100, and 200 mM protected corneal epithelial cells in culture from death by desiccation. Trehalose could be used as a potential new eye drop for dry eye syndrome.

Cell Survival↗
PubMed2001

Acute respiratory failure due to "pulmonary calciphylaxis" in a maintenance haemodialysis patient.

Calciphylaxis is a rapidly developing, fatal process of vascular calcium deposition with prominent cutaneous manifestation. We treated a long-term haemodialysis patient who developed an analogous disorder limited to the lungs. A 57-year-old man was admitted for initiation of peritoneal dialysis because limited cardiac reserve precluded further haemodialysis. He was treated successfully for pneumonia until hypoxia and progressive hypercalcaemia developed. (99m)Tc-methylene disphosphonate scintigraphy showed diffusely increased pulmonary uptake. Death supervened despite aggressive and successful treatment of hypercalcaemia. Autopsy studies included immunohistochemistry and morphometric studies of bone. Alveolar capillary walls showed diffuse calcium deposition. Both gross and microscopical findings differed from those of typical metastatic calcification in dialysis patients. Immunoreactivity for parathyroid hormone-related protein was present in the lesions. Bone histomorphometry indicated mild osteitis fibrosa. Pneumonia is believed to have caused local synthesis of parathyroid hormone-related protein that, along with high calcium x phosphorus product, contributed to calcium deposition. By analogy with the cutaneous process we termed the deposition "pulmonary calciphylaxis".

Acute Disease↗
PubMed2001

Hospital charges attributable to bronchoscopy-related complications in outpatients.

BACKGROUND: Despite literature pertaining to algorithms of care, operating room charges and other financial management issues in medicine, there is a paucity of data pertaining to the fiscal consequences of bronchoscopic practice. OBJECTIVE: To identify hospital charges directly attributable to bronchoscopy-related complications in outpatients. METHODS: A prospective analysis of outpatient bronchoscopy-related complications, clinical outcomes and hospital charges resulting directly from procedure-related adverse events in 660 consecutive outpatients undergoing flexible fiberoptic bronchoscopy (FFB) during a period of 30 consecutive months at the University of California, San Diego Medical Center, was performed. RESULTS: Altogether, 1,009 consecutive outpatient FFBs were performed on 660 patients (mean age 58 years, range 16-91 years). Fifty adverse events (5% of all procedures) occurred in 44 patients. These were bronchospasm (31 cases), hemoptysis (5 cases), pneumothorax (3 cases), nausea/vomiting (3 cases), hypoxemia (2 cases), seizure (2 cases), laryngeal spasm (2 cases), chills/fever (1 case) and a vasovagal episode (1 case). Prolonged length of stay in the postprocedure recovery area on 22 occasions (2.2% of all procedures) resulted in USD 6,996 in additional hospital charges. Hospitalization was necessary in only 5 instances (0.5% of all procedures), but resulted in USD 34,500 in additional charges (range for the 5 patients, USD 2,000-11,000) that were directly attributable to a procedure-related complication. CONCLUSION: Hospital charges directly attributable to outpatient flexible bronchoscopy-related complications are minimal, but escalate considerably if hospitalization becomes necessary.

Adolescent↗
PubMed2001

Stroke prognosis and abnormal nocturnal blood pressure falls in older hypertensives.

It remains uncertain whether abnormal dipping patterns of nocturnal blood pressure influence the prognosis for stroke. We studied stroke events in 575 older Japanese patients with sustained hypertension determined by ambulatory blood pressure monitoring (without medication). They were subclassified by their nocturnal systolic blood pressure fall (97 extreme-dippers, with >/=20% nocturnal systolic blood pressure fall; 230 dippers, with >/=10% but <20% fall; 185 nondippers, with >/=0% but <10% fall; and 63 reverse-dippers, with <0% fall) and were followed prospectively for an average duration of 41 months. Baseline brain magnetic resonance imaging (MRI) disclosed that the percentages with multiple silent cerebral infarct were 53% in extreme-dippers, 29% in dippers, 41% in nondippers, and 49% in reverse-dippers. There was a J-shaped relationship between dipping status and stroke incidence (extreme-dippers, 12%; dippers, 6.1%; nondippers, 7.6%; and reverse-dippers, 22%), and this remained significant in a Cox regression analysis after controlling for age, gender, body mass index, 24-hour systolic blood pressure, and antihypertensive medication. Intracranial hemorrhage was more common in reverse-dippers (29% of strokes) than in other subgroups (7.7% of strokes, P=0.04). In the extreme-dipper group, 27% of strokes were ischemic strokes that occurred during sleep (versus 8.6% of strokes in the other 3 subgroups, P=0.11). In conclusion, in older Japanese hypertensive patients, extreme dipping of nocturnal blood pressure may be related to silent and clinical cerebral ischemia through hypoperfusion during sleep or an exaggerated morning rise of blood pressure, whereas reverse dipping may pose a risk for intracranial hemorrhage.

Aged↗
PubMed2001

Microvascular angina in a patient with aortic stenosis.

A 39-year-old woman had exercise-induced ST segment depression associated with chest pain. Cardiac evaluation revealed moderate aortic stenosis (AS), related to the bicuspid valves, with an aortic mean pressure gradient of 22 mmHg, a calculated aortic valve area of 1.3 cm2 and normal left ventricular (LV) peak systolic and end-diastolic pressures, but no LV hypertrophy, resulting in normal LV wall stress. Although the coronary arteries were angiographically normal, rapid atrial pacing and an intracoronary papaverine injection revealed a significantly decreased coronary flow reserve (CFR), which may have played an important role in the pathogenesis of angina pectoris in this patient. Though the CFR is usually decreased in patients with AS, as well as in microvascular angina, in this particular case, it appeared to have decreased as a consequence of microvascular dysfunction rather than of AS-related mechanisms.

Adult↗
PubMed2001

Involvement of angiotensin II in progression of renal injury in rats with genetic non-insulin-dependent diabetes mellitus (Wistar fatty rats).

Wistar fatty (WF) rats have a genetic predisposition to hyperglycemia, polyuria, hyperinsulinemia, hyperlipidemia, obesity and nephropathy. These phenotypic characteristics are similar to those observed in obese patients with non-insulin-dependent diabetes mellitus (NIDDM) nephropathy. In this study, the effects of two types of renin-angiotensin system inhibitors, an angiotensin II type 1-receptor antagonist (AT1A) and an angiotensin I-converting enzyme inhibitor (ACEI), on renal injury in WF rats were studied during the progressive phase of diabetic nephropathy. An AT1A, candesartan cilexetil (1 mg/kg), and an ACEI, enalapril (10 mg/kg), were administered orally once a day for 12 weeks, beginning when the rats were 27-week-old and already showed diabetic nephropathy and obesity. Both drugs prevented an increase in proteinuria during the experimental period. Furthermore, after 4-week intervention, the levels of proteinuria were markedly lower in drug-treated rats. At the end of the experiment, both drugs prevented the development of glomerular lesions without affecting glucose metabolism and obesity. In conclusion, the inhibition of angiotensin II activity ameliorated both existing proteinuria and the progression of proteinuria, resulting in preservation of glomerular structure. Thus angiotensin II plays important roles in the development and the progression of nephropathy in genetically obese diabetic WF rats.

Angiotensin II↗
PubMed2001

Complete nucleotide sequence of the cytochrome b gene of channel catfish Ictalurus punctatus and comparison of sequence homology among channel catfish and other fishes.

To clarify the phylogenic relationship of channel catfish with other fishes, the cytochrome b (Cyt b) gene of the catfish was cloned and sequenced. Channel catfish (Ictalurus punctatus) belonging to the family Ictaluridae in the order Siluriformes showed a 78.4-87.4% similarity to all but one fish of the family Cyprinidae and river loach Crossostoma lacustre of the family Balitoridae in the order Cypriniformes in which genes had already been sequenced, and a 97.2% similarity to the goldfish (Carassius auratus) belonging to the family Cyprinidae. Within the family Cyprinidae, a 78.8-89.2% similarity to one another was recorded. In addition, the similarity rate between the family Cyprinidae and the family Balitoridae reached a value of 77.8-79.9% in the order Cypriniformes. Furthermore, in an unrooted phylogenetic tree consisting of four branches among eight fishes, channel catfish and goldfish appeared in the same branch. These results suggested that the Cyt b gene of the channel catfish in the order Siluriformes was closely related to that of a goldfish in the order Cypriniformes. The results were not agreement with the morphological classification. Genetic reclassification of the fishes may be necessary to identify the ancestor. This is the first report on the cloning and complete sequencing the Cyt b gene of the channel catfish which may contribute to the genetic reclassification of catfishes belonging to the order Siluriformes.

Amino Acid Sequence↗
PubMed2001

Glycidol degrades scrapie mouse prion protein.

Agents of transmissible spongiform encephalopathy (prion) are known to be extremely resistant to physicochemical inactivation procedures such as heat, radiation, chemical disinfectants such as detergents, alcohols, glutaraldehyde, formalin, and so on. Because of its remarkable resistance, it is difficult to inactivate prion. Chemical inactivation seems to be a practical method because it is applicable to large or fixed surfaces and complicated equipment. Here, three epoxides: beta-propiolactone, propylene oxide, and glycidol (GLD) were examined of their inactivation ability against scrapie-mouse prion protein (PrP(Sc)) under various conditions of chemical concentration, incubation time, and temperature. Among these chemicals, GLD worked most effectively and degraded PrP into small fragments. As a result of the bioassay, treatment with 3% GLD for 5 hr and 5% GLD for 2, 5 hr or 12 hr at room temperature prolonged the mean incubation time by 44, 30, 110 and 73 days, respectively. From dose-incubation time standard curve, the decrease in infectivity titers were estimated as 10(3) or more. Therefore, degradation of PrP(Sc) by GLD decreased the scrapie infectivity. It is also suggested that pH and salt concentrations influence the effect of GLD. Although further study is necessary to determine the optimal condition, GLD may be a potential prion disinfectant.

Animals↗
PubMed2001

Analysis of the KAL1 gene in 19 Japanese patients with Kallmann syndrome.

Kallmann syndrome is defined by the association of hypogonadotropic hypogonadism and anosmia. The KAL1 gene is responsible for the X-linked form of Kallmann syndrome. We analyzed the KAL1 gene in 19 Japanese patients with Kallmann syndrome, including 3 patients reported previously, using PCR-direct sequencing method. All of 19 patients were sporadic, except for 2 monozygotic twins. In this study, there were 3 kinds of mutations in the KAL1 gene. One of them was a novel mutation consisting of a G to A substitution in the acceptor site at the junction of intron 6/exon 7. None of the mutations have been reported in countries other than Japan. In male sporadic patients with Kallmann syndrome, the incidence of mutations in Japanese patients (14%: 2 of 14 cases) was slightly higher than that in patients in USA (8%). Also, we found 2 polymorphisms, which were always found together in 6 patients. The severity of hypogonadism was not related to the presence of mutations. Unilateral renal aplasia and mirror movement, which are frequently found in patients with the KAL1 gene mutation, were not related to the sites of mutations.

Adolescent↗
PubMed2001

[Reference values for lead in blood in urban population in southern Brazil].

OBJECTIVE: To describe the reference values for lead in blood in an urban population in the city of Londrina, in the state of Paraná, Brazil. MATERIALS AND METHODS: The reference population was composed of 520 adult volunteers who were assessed from November 1994 to December 1996. Exclusion criteria were: occupational exposure to lead, exposure through personal habits or practices, smoking more than 10 cigarettes per day, and living near industrial plants or other places that use lead in their production processes. Also excluded were individuals with abnormal clinical or laboratory results or with chronic diseases or cardiovascular disorders. Lead blood levels were determined using air-acetylene flame atomic absorption spectrophotometry. The detectable limit was 1.23 micrograms/dL. After the analyses of lead in blood, the following values were determined: minimum value, first quartile, median, third quartile, and maximum value; geometric mean; 95% confidence interval; experimental interval; and reference value. RESULTS: The reference values for lead in blood ranged from 1.20 micrograms/dL to 13.72 micrograms/dL. The geometric mean was 5.5 micrograms/dL. CONCLUSIONS: In general, the values found in this study are lower than those that have been reported for other countries. Additional data should be gathered from Brazilian populations living in more-industrialized areas.

Adult↗
PubMed2001

Acute cholestatic hepatitis caused by a probable allergic reaction to paracetamol in an adolescent.

We reported on an adolescent who suffered from cholestatic hepatitis after taking a low dose of paracetamol. It was suspected that the condition was brought about by an allergic reaction to paracetamol. Paracetamol is one of the representative intrinsic hepatotoxic drugs. There have been only a few reports on liver damage due to an allergic reaction to paracetamol. There is a need to call attention to this particular reaction.

Acetaminophen↗
PubMed2001

X-ray absorption spectral analyses by theoretical calculations for TiO2 and Ni-doped TiO2 thin films on glass plates.

Ni L- and Ti L-edge as well as Ti K-edge X-ray absorption experiments for TiO2 thin films and Ni-doped TiO2 thin films coated on glass plates were performed using synchrotron radiation to investigate the structures around Ni and Ti ions in the films. The obtained spectra were compared with the results of theoretical calculations. It has consequently been found that the spectral features were affected by a change in the oxidizing form of Ni ions due to hydrogen reduction, by the charge variation and/or slight orbital splitting of Ti ions, and by the magnitude of the interaction between the center Ti ion and neighboring Ti ions.

Journal Article↗