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Biomedical subjects

T Matsuo

Publications and source records attributed to T Matsuo.

At least 199 records · Page 11Linked to original sources
PubMed1999

Experimental and clinical evaluation of the harmonic scalpel in thoracic surgery.

The Harmonic Scalpel is an ultrasonic instrument for cutting and coagulating tissue. We are reporting our evaluation of the Harmonic Scalpel safety and efficacy in both experimental and clinical thoracic surgery. First, we confirmed the safety in thoracic surgery by following two preliminary studies using the Harmonic Scalpel. 1: Pulmonary parenchyma was incised using "Coagulating Shears" to evaluate hemostasis and air leakage. 2: Pulmonary hilar vessels were contacted directly with "Dissecting Hook" blade at optimum cutting power mode to evaluate potential vascular wall injury by the Harmonic Scalpel. Subsequently, the Harmonic Scalpel was used for a partial lung resection due to metastatic lung cancer. Particular application was for a chest wall incision, interlobar separation of the lung, and dissection of a pulmonary artery, in lung cancer operations. We concluded that cutting and hemostasis of pulmonary parenchyma could be achieved with minimal tissue damage using the Harmonic Scalpel. Compared to electric coagulation, the Harmonic Scalpel minimizes tissue charring and dissection, and eliminates thermal injury in thoracic surgery.

Animals↗
PubMed1999

Effects of high-fat diet intake on glucose uptake in central and peripheral tissues of non-obese rats.

We previously demonstrated that plasma glucose concentration was higher while plasma insulin concentration was lower in rats fed a high-fat diet. In the present study, we examined the effects of high-fat diet on glucose uptake in central and peripheral tissues in non-obese rats. Forty male Sprague-Dawley rats were fed high- or low-fat diets for 4 wk. Body weight and body fat accumulation were not different between the two diet groups after 4 wk. Glucose uptake in the skeletal muscles and adipose tissues, estimated by the 2-deoxy-D-glucose method, was lower in the rats fed the high-fat diet than that in the rats fed the low-fat diet, whereas uptake in the liver and pancreas did not differ between the two groups. Glucose uptake in the hypothalamus and cortex was higher in the high-fat diet group as compared with that in the low-fat diet group. These results suggest that increased plasma glucose levels in rats fed the high-fat diet were caused by a decrease in glucose uptake in the skeletal muscles and adipose tissues. Reduced plasma insulin level in the high fat diet group with no difference in glucose uptake in the pancreas may be due to increased sympathetic activity in the pancreas resulting from the increased glucose uptake in the brain regions involved in autonomic functions.

Adipose Tissue↗
PubMed1999

Adhesion of a new commercial self-etching/self-priming bonding resin to human caries-infected dentin.

We have examined the adhesive properties of a new commercial self-etching/self-priming bonding resin (Unifil Bond, UB) to normal and caries-infected dentin of human extracted molars using scanning electron microscopy (SEM) and a micto-tensile bonding strength (MTBS) test. In this study, 7 human extracted molars with moderate occlusal caries were used, and flat surfaces including occlusal dentin caries were prepared from the teeth. After the application of UB to the surfaces, a composite resin was built up, and subjected to the measurement of MTBS and SEM observation of the interfacial morphology between UB and dentin. The MTBS of UB to normal dentin was 33.4 MPa, but that to caries-infected dentin was 11.0 MPa. There was a significant difference between the MTBS to normal and carious dentin. SEM observation revealed that the typical hybrid layer was not formed in caries-infected dentin. These results suggested that resin infiltration into caries-infected dentin was not sufficient to allow perfect sealing of the restoration.

Acid Etching, Dental↗
PubMed1999

[Adverse reactions to autologous peripheral blood stem cell transplantation in patients over 65 years old].

We compared the outcomes of autologous peripheral blood stem cell transplantation (auto-PBSCT) for two groups: one composed of 6 patients over 65 years of age, and the other, of 8 younger patients. Transfused CD34-positive cells and CFU-GM counts, days to achieve a neutrophil count of over 500/microliter after transplantation, days to achieve a platelet count of over 50,000/microliter, and blood transfusion times were similar in both groups. Organ toxicity also appeared similar in both groups, but no severe adverse reactions (WHO grade/4) were observed. Poor performance status due to advanced tumors improved in some patients after PBSCT. We concluded that PBSCT is tolerable in patients over 65 years of age and useful as salvage therapy.

Age Factors↗
PubMed1999

The evolution of cerebral blood flow in the developing brain: evaluation with iodine-123 iodoamphetamine SPECT and correlation with MR imaging.

BACKGROUND AND PURPOSE: Although it is well established that brain maturation correlates temporally with the functions the newborn or infant performs at various stages of development, the precise relationship between function and anatomic brain maturation remains unclear. The purpose of this study was to investigate the developmental changes of regional cerebral blood flow (rCBF) in infants and children using iodine-123 iodoamphetamine (123I-IMP) and single-photon emission computed tomography (SPECT). These findings were correlated with the MR imaging appearance of the brain and with known developmental changes. METHODS: Twenty-one 123I-IMP SPECT examinations of 17 patients, ranging in age from neonates to 2 years, were reviewed retrospectively. All children had had transient neurologic events in the neonatal period that did not significantly affect subsequent neuropsychological development. MR studies were performed in 12 of these patients and the MR findings were correlated with the SPECT results. RESULTS: SPECT studies showed a consistent pattern of evolving changes in 123I-IMP uptake, most likely reflecting evolution of rCBF. From the 34th postconceptional week until the end of the second month after term delivery, there was predominant uptake in the thalami, brain stem, and paleocerebellum, with relatively less cortical activity. Radionuclide uptake in both the perirolandic and occipital cortices was well seen around the 40th postconceptional week and increased rapidly thereafter, with a predominance of parietal activity. By 3 months, radionuclide uptake in the cerebellar hemispheres and parietofrontal cortices increased. Frontal and temporal activity increased by age 6 to 8 months. Uptake in the basal ganglia increased by 8 months. By the beginning of the second year, rCBF showed a similar topographic pattern to that in adults. CONCLUSION: The time course of the changes in 123I-IMP uptake in the developing brain as detected by SPECT is similar to that of myelination and most likely reflects an overall topologic maturational pattern of the brain.

Amphetamines↗
PubMed1999

Relationships between activity of daily living, and oral cavity care and the number of oral cavity microorganisms in patients with cerebrovascular diseases.

We examined the relationships among the activity of daily living (ADL), oral cavity care, and the number of oral cavity microorganisms in 40 patients with cerebrovascular diseases (CVD). The CVD patients were classified into 4 groups, I, II, III and IV based on their ADL and the method used for oral cavity care. The ADL was highest in group I and lowest in group III. Only the patients of only group III could not eat by themselves and were receiving naso-esophageal feeding. Oral cavity care was performed by the patients themselves in groups I and IV, but was performed by caregivers in groups II and III. The group IV patients had no teeth, but could eat by themselves using full dentures. The numbers of microorganisms in the pharyngeal swabs from the 4 groups were measured and expressed as colony-forming units (cfu). The numbers of both Staphylococci spp. and Candida spp. were significantly higher in group III than in the other groups. Moreover, Pseudomonas aeruginosa was isolated only from patients of group III (in about 66%). The oral cavity care by caregivers was almost the same in groups II and III, but the numbers of oral cavity microorganisms were significantly higher in group III than in group II. These results indicated that microorganisms grow more easily in the oral cavities of CVD patients with low ADL compared with CVD patients with higher ADL, and that eating is thought to be important for the prevention of an increase of microorganisms in the oral cavity.

Activities of Daily Living↗
PubMed1999

Disappearance of complete atrioventricular block after chemotherapy for malignant lymphoma: a case report.

A 77-year-old man with malignant lymphoma presented with dizziness and exertional dyspnea. Physical examination revealed marked bradycardia (36 beats/min). Twelve-lead electrocardiography showed complete atrioventricular block with narrow QRS escape beats. Gallium scintigraphy demonstrated significant abnormal uptake in the heart. Transesophageal echocardiography showed a thick interatrial septum with increased echogenecity. He underwent chemotherapy under external temporary pacing with a suspected diagnosis of complete atrioventricular block secondary to cardiac invasion of malignant lymphoma. Atrioventricular conduction progressively improved and the complete atrioventricular block disappeared. He is currently well and has required no cardiac pacing for 6 months. We conclude that complete atrioventricular block may be reversible in some patients with malignant lymphoma, even in the elderly.

Aged↗
PubMed1999

Chemotherapeutic malaria control as a selective primary health care activity in the Solomon Islands.

Malaria control by chemotherapy has been established in rural villages of Guadalcanal, the Solomon Islands, following field trials. As a selective primary health care activity, mobile unit teams visited villages once or twice a year to detect malaria positives and gave chloroquine and primaquine to treat the infection and interrupt the transmission. On site diagnosis was by the use of acridine orange fluorescent staining or the ICTPf commercial diagnostic kit. To avoid possible haemolytic crises, a new single step screening method of G6PD deficiency was introduced. This approach has been accepted well by villagers and proved to be an efficient and feasible control method even in remote rural villages with endemic malaria transmission. Epidemiological modelling of the situation predicts reduction of prevalence in five years.

Adult↗
PubMed1998

Highly sensitive hepatitis B surface antigen detection by measuring stable nitroxide radical formation with ESR spectroscopy.

In areas where hepatitis B virus (HBV) is prevalent, HBV carriers negative for hepatitis B surface antigen (HbsAg) by enzyme-linked immunosorbent assay (ELISA) have been reported. Moreover, even after screening donor blood for HbsAg and hepatitis B core antibody (HBcAb), post-transfusion hepatitis B continues to occur, though with a decreasing frequency. Therefore, screening tests far more sensitive for detecting HBsAg than those currently available are needed. We developed a highly sensitive method for HBsAg detection. It is based on the recognition of peroxidase activity through measuring the formation of stable nitroxide radical with electron spin resonance (ESR) spectroscopy in the presence of hydrogen peroxide, p-acetamidophenol (p-AP), and 4-hydrazonomethyl-1-hydroxy-2,2,5,5,-tetramethyl-3-imidazoline-3-o xide (HHTIO). A cut-off value was established by testing of 186 healthy adults and 50 HBsAg-positive individuals. The signal to noise (S/N) ratio of less than 1.488 obtained by ESR spectroscopy was considered to be negative and more than 2.181, positive. The p-AP/HHTIO method was found to be 10 times more sensitive than the standard ELISA and reproducibility was excellent. Additional investigations were made on the HBsAg levels in the serum from 26 healthy subjects, in whom cut-off index levels on ELISA were negative but relatively high (range: 0.6 to 1.0); and on 15 patients with non B non C hepatitis. Three of 26 cases and 3 of 15 with non B non C hepatitis were judged to be HBsAg positive. Of these, 5 were found to be positive for HBV DNA by polymerase chain reaction (PCR). It was shown in this study that the p-AP/HHTIO method is practical and useful in screening HBV carriers because of the sensitivity in HBsAg detection, which is comparable to PCR analysis.

Acetaminophen↗
PubMed1998

Redox-controlled ligand exchange of the heme in the CO-sensing transcriptional activator CooA.

The transcriptional activator CooA from Rhodospirillum rubrum contains a b-type heme that acts as a CO sensor in vivo. CooA is the first example of a transcriptional regulator containing a heme as a prosthetic group and of a hemeprotein in which CO plays a physiological role. In this study, we constructed an in vivo reporter system to measure the transcriptional activator activity of CooA and prepared some CooA mutants in which a mutation was introduced at Cys, His, Met, Lys, or Tyr. Only the mutations of Cys75 and His77 affected the electronic absorption spectra of the heme in CooA. The electronic absorption spectra, EPR spectra, and the transcriptional activator activity of the wild-type and mutant CooA proteins indicate that 1) the thiolate derived from Cys75 is the axial ligand in the ferric heme, but it is not coordinated to the CO-bound ferrous heme; 2) Cys75 is protonated or displaced in the ferrous heme; and 3) His77 is the proximal ligand in the CO-bound ferrous heme and probably also in the ferrous heme, but it is not coordinated to the ferric heme. NMR spectra reveal that the conformational change around the heme, which will trigger the activation of CooA by CO, takes place upon the binding of CO to the heme.

Bacterial Proteins↗
PubMed1998

Spatiotemporal measurement of free radical elimination in the abdomen using an in vivo ESR-CT imaging system.

Electron spin resonance (ESR) imaging can visualize the distribution of free radicals in living systems according to their concentrations. However, the application of ESR imaging to living animals has not been well established. Using a rapid field scan L-band ESR imaging system, we have successfully obtained two-dimensional ESR projection (xz-plane projection) and three-dimensional ESR-CT (trans-axial section along the y-axis) images of the abdomen of living mice after an injection of 3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (carbamoyl-PROXYL) into the tail vein. The in vivo two-dimensional ESR projection imaging clearly visualized the carbamoyl-PROXYL distribution and the rapid decay process in the abdomen. Because among the viscera, the liver is most abundantly associated with a blood volume, the outline of the image can be composed mainly of this organ. We therefore attempted to find whether there will be a difference in spatiotemporal dynamics of carbamoyl-PROXYL in the abdomens between the control and the mice with liver damage by two-dimensional ESR projection. In the control mice, carbamoyl-PROXYL was almost completely eliminated from the abdomen within 5 minutes after administration. On the other hand, in mice with carbon tetrachloride-damaged livers, the decay of carbamoyl-PROXYL was markedly prolonged. Even at 5 min after administration, carbamoyl-PROXYL remained clearly visible in the abdomen. In vivo three-dimensional ESR-CT imaging showed an even distribution of carbamoyl-PROXYL throughout the whole liver, which corresponded well with the images of trans-axial sections of the murine abdomen. We have succeeded in displaying two-dimensional ESR projection and three-dimensional ESR-CT images of carbamoyl-PROXYL distribution and clearance in the abdomen of a living animal. The ESR-CT imaging technique is considered to be a powerful new tool for noninvasive investigations of the in vivo spatiotemporal dynamics of free radical distribution and elimination in the organs.

Abdomen↗
PubMed1998

p27Kip1: a key mediator of retinoic acid induced growth arrest in the SMS-KCNR human neuroblastoma cell line.

Retinoic acid (RA) treatment of SMS-KCNR neuroblastoma (NB) cells leads to G1 growth arrest and neuronal differentiation. To investigate the molecular mechanisms by which RA alters cell growth, we analysed the expression and activity of components of the cell cycle machinery after culture in RA. Within 2 days of RA treatment and prior to the arrest of NB cells in the G1 phase of the cell cycle, there is a complete downregulation of G1 cyclin/Cdk activities. Protein levels for the G1 cyclin/Cdks were essentially unchanged during this time although there was a decrease in the steady-state levels of p67N-Myc and hyperphosphorylated Rb proteins. The Cdk inhibitors, p21Cip1 and p27Kip1 were constitutively expressed in KCNR while p15INK4B and p16INK4A were not detected. RA induced an increase in the expression of p27Kip1 but not p21Cip1. Furthermore, coincident with the decrease in kinase activity there was an increase in G1 cyclin/Cdk bound p27Kip1. These results indicate that changes in the level of p27Kip1 and its binding to G1 cyclin/Cdks may play a key role in RA induced growth arrest of NB cells.

Antineoplastic Agents↗
PubMed1998

Granular Cell Tumor of the Breast: A Case Report Describing Dynamic MR Mammography.

A case of granular cell tumor of the breast in a 36-year-old woman is reported. The patient presented with a hard mass,1.5 cm in diameter in the upper-outer quadrant of the left breast. Physical examination and ultrasonography suggested the presence of breast carcinoma. An aspiration biopsy cytology(ABC)specimen wasevaluated as class II, and dynamic magnetic resonance(MR)mammography indicated a benign tumor. Granular cell tumor was finally diagnosed on examination of an excisional biopsy specimen. Granular cell tumor of the breast can mimic breast carcinoma on physical examination, mammography, ultrasonography, and even gross inspection. Dynamic MR mammography has the potential distinguish this condition from carcinoma. Awareness of this disease and prudent use of diagnostic procedures, including MR mammography, will help prevent misdiagnosis and unnecessary surgery.

Journal Article↗
PubMed1998

In situ visualization of messenger RNA for basic fibroblast growth factor in living cells.

We examined whether messenger RNA for basic fibroblast growth factor (bFGF) could be visualized specifically by a fluorescent probe in living cells. A 15-nucleotide-long antisense or sense sequence for human bFGF was sandwiched between two complementary 5-nucleotide-long arm sequences. A fluorophore, 5-(2'-aminoethyl)aminonaphthalene-1-sulfonic acid (EDANS), was joined to the 5'-terminal phosphate, while 4-(4'-dimethylaminophenylazo)benzoic acid, quencher for EDANS, was joined to the 3'-terminal hydroxyl group. The probe emitted blue fluorescence only upon hybridization with the complementary 18-nucleotide-long sequence under ultraviolet light. The antisense or sense probe carried with liposome was delivered to human cells, trabecular cells of the eye, in a glass-bottom culture dish placed on the stage of an inverted microscope. Cells with the antisense probe did, but not with the sense probe, show blue fluorescence under ultraviolet light. The present study opens a way to measure the changing levels of a specific messenger RNA in living cells.

Base Sequence↗
PubMed1998

Feeder vessel photocoagulation of subfoveal choroidal neovascularization secondary to age-related macular degeneration.

PURPOSE: This study aimed to assess the feasibility of laser photocoagulation of feeder vessels of subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration. PATIENTS AND METHODS: Of 170 consecutive patients with subfoveal CNV secondary to age-related macular degeneration, feeder vessels were detected in 37 patients by means of indocyanine green videoangiography using a scanning laser ophthalmoscope. Dye laser photocoagulation was applied to extrafoveal feeder vessels, with the fovea spared. RESULTS: Twenty-six (70%) of those 37 patients had complete resolution of exudative manifestations. Persistent or worsened manifestations were seen in 11 patients (30%) because of recurrent CNV or persistent CNV. The visual acuity improved or stabilized in 25 patients (68%). Ten patients (27%) had a final visual acuity of 20/40 or better and six patients (16%) had a final visual acuity of 20/50 to 20/100. Significant factors prognostic of the visual outcome of 20/100 or better were small CNV (2 disc areas or smaller, Fisher's exact probability test, P = 0.041), the absence of white, fibrous tissue in neovascular membranes (Fisher's exact probability test, P = 0.003), and the closest distance of laser burns to the center of the foveal avascular zone (Fisher's exact probability test, P = 0.049). Preoperative visual acuity had a significant positive correlation with final visual acuity (Spearman's rank correlation test, P = 0.0076). CONCLUSION: Feeder vessel photocoagulation should be considered as a treatment option for subfoveal CNV secondary to age-related macular degeneration, because no other treatment method has a better visual outcome.

Aged↗