Search PubMed⌕ Search

Biomedical subjects

T Shimono

Publications and source records attributed to T Shimono.

At least 145 records · Page 8Linked to original sources
PubMedDate not supplied

CT imaging of biliary enteric fistula.

BACKGROUND: To define the signs useful for differentiating between gallbladder-enteric fistula (GB-EF) and common bile duct-enteric fistula (CBD-EF) on computed tomography (CT) because the prognosis and management of the two are different. METHODS: CT scans in 13 patients with pneumobilia, who had not had surgical biliary-enteric anastomosis and endoscopic sphincterotomy, were reviewed. The presence of fistula itself, the location of air in the biliary system, and the appearance of the gallbladder were assessed. RESULTS: The causes of pneumobilia were GB-EF in seven patients, CBD-EF in three patients, emphysematous cholecystitis (EC) in one patient, gallbladder cancer (GBC) in one patient, and incompetent sphincter of Oddi in one patient. In three of seven GB-EF patients (43%) and in none of the three CBD-EF patients (0%), the fistula itself was detected. Air was detected in the common bile duct in four of seven GB-EF (57%) and in all three CBD-EF (100%) patients, and GBC. In six of seven GB-EF (86%) and in one of three CBD-EF (33%) patients, the gallbladder was contracted. Thus, the location of air and the contraction of gallbladder were useful signs to differentiate GB-EF from CBD-EF. CONCLUSION: CT can distinguish between GB-EF and CBD-EF.

Aged↗
PubMedDate not supplied

Treatment of chronic type B aortic dissection with endovascular stent-graft placement.

A 74-year-old man with chronic aortic dissection was treated with an endovascular stent graft, fabricated from expanded polytetrafluoroethylene and a Z-stent. It was placed in the true lumen to close an entry tear. Closure was obtained immediately and thrombosis of the false lumen at the descending thoracic aorta was observed on computed tomography (CT) obtained 1 week later. No procedure-related complications developed. The patient is doing well with no adverse events including aortic rupture or aortic branch ischemia.

Aged↗
PubMedDate not supplied

Experimental evaluation of a newly developed ultrathin silicone layer coated hollow fiber oxygenator.

The authors developed a new membrane oxygenator that consists of microporous polypropylene hollow fibers coated with a 0.2 micron ultrathin silicone layer. Five venoarterial bypasses were conducted on mongrel dogs for 24 hr using these new oxygenators. The blood flow rate was maintained at 750 ml/min, and the V/Q ratio was maintained at 1:1. As a control, three venoarterial bypasses were conducted under the same conditions using an oxygenator with the same design but without the silicone coating. Eight to 16 hr after the initiation of bypass, severe plasma leakage occurred in all control experiments, so the bypasses were terminated. However, plasma leakage did not occur throughout the 24 hr of any of the experiments using the new oxygenator. The O2 transfer rate of the new oxygenators after 24 hr of perfusion was 59.7 +/- 6.6 ml/min/m2, and the plasma free hemoglobin level 8 hr after the initiation of bypass was 41.4 +/- 40.2 mg/dl, compared with 145.3 +/- 189.6 mg/dl in the control group. Scanning electron microscopic examination of the silicone coated fibers after 24 hr of bypass revealed a few scattered platelet adherents and no damage to the silicone coated surface. These results suggest that this new oxygenator has satisfactory gas transfer and good durability.

Animals↗
PubMedDate not supplied

Effect of ultrafiltration on priming solution with preserved blood for extracorporeal circulation in infants.

In pediatric cardiac surgery, the initial priming solutions of the extracorporeal circulation include preserved blood. In an effort to eliminate unfavorable effects of preserved blood on the circulation, the authors introduced the preserved blood to ultrafiltration (UF). Seventeen infants with congenital heart defects were included in this study. UF was performed with a polysulfone ultrafiltrator before extracorporeal circulation. The 1600 ml of fluid, consisting of saline, 5% glucose, and maltose, were added to 400 ml of preserved blood, and the same amount of fluid was removed by UF. The concentrations of potassium, NH3, and bradykinin in the priming blood decreased significantly after UF. In the UF group, water balance during extracorporeal circulation and max. Creatinine-phosphokinase levels after surgery were better than controls. These data suggest that UF is able to remove some substances and result in reduction of an unfavorable effect on the circulation.

Blood Preservation↗
PubMedDate not supplied

Comparative studies of glycoprotein Ib in heparin coated and nonheparin coated extracorporeal circulation circuits.

Contact between blood and artificial materials has various effects on blood. Impairment of platelet function is an especially important and well known effect, but its precise mechanism is not clearly understood. The authors constructed a circulation model to investigate the effect of extracorporeal circulation on platelet membrane glycoproteins (GPs), especially GP Ib, and to compare the changes in GP Ib in heparin coated (group C) and nonheparin coated (group N) circuits. As determined by flow cytometry, GP Ib in both groups decreased on initiating circulation, but the decrease in group N was significantly larger than that in group C. There was no observed change in GP IIb/IIIa levels in either group. The extent of shear stress induced platelet aggregation significantly decreased during circulation in both groups. Decreases in the extent of shear stress induced platelet aggregation were significantly less with the use of heparin coated circuits. In addition, the amount of GP Ib in the high speed pellet decreased progressively during circulation in both groups. In contrast, the amount of GP Ib in the Triton insoluble (low speed) pellet increased dramatically during circulation. However, expression of GP Ib in the Triton soluble platelet fraction was low in both groups. From the results, it was concluded that the cause of the decrease in platelet function during extracorporeal circulation is attributable to the internalization of GP Ib from the platelet surface inside the platelet. It also can be said that a heparin coated circuit is one effective means of controlling this change.

Blood Platelets↗
PubMedDate not supplied

Identifying risk factors for predicting caries in school-aged children using dental health information collected at preschool age.

The study was done to identify toddlers who have an increased risk of developing dental decay at school age. Six variables-Cariostat score, mother's ethnicity, evidence of baby bottle tooth decay, mother;s dental health status, toddler's age at first tooth, and frequency of brushing - showed a significant association with decay status at school age with odds ratios ranging from 1.89 to 2.63. The Cariostat score and the frequency of brushing remained significant in a logistic regression. No interaction terms were significant. The Cariostat caries activity test would be a useful screening tool for identifying toddlers most likely to develop decay or could be used periodically as the deciduous molars erupt and become colonized with oral bacteria. The findings confirm that good oral hygiene practices can have an impact on future dental health, and caregivers should be encouraged to brush young children's teeth regularly.

Alberta↗
PubMedDate not supplied

Preoperative evaluation and surgical treatment for tricuspid regurgitation associated with acquired valvular heart disease. The Kay-Boyd method vs the Carpentier-Edwards ring method.

This study compared the results of annuloplastic repair of tricuspid regurgitation (TR) using Doppler echocardiography. Sixty-three patients who underwent tricuspid annuloplasty were studied. Thirty-four patients received Kay-Boyd annuloplasty and 29 Carpentier-Edwards ring annuloplasty. A new classification of TR based on the direction and area of regurgitation flow on Doppler echocardiogram was applied preoperatively. In the Kay-Boyd group, 10 cases showed massive TR and 24 cases showed localized TR preoperatively. Localized TR was well controlled in all cases, but 8 of 9 cases of massive TR showed grade III residual TR. In the C-E group, 21 cases showed massive TR and 8 cases showed localized TR. All cases were well controlled postoperatively. We conclude that (1) although the Kay-Boyd method is acceptable for localized TR, the C-E method should be employed for massive TR; (2) analyzing the regurgitant pattern of TR by Doppler echocardiogram is useful in selecting an appropriate surgical technique.

Adult↗
PubMedDate not supplied

A longitudinal assessment of predictive value of a caries activity test in young children.

A longitudinal study was conducted in Okayama, Japan to investigate the predictive value of a caries activity test (Cariostat). The subjects were 100 children who participated in routine dental examinations at 18, 24 and 36 months. Results indicated caries prevalence of 9% at 18 months, 21 percent at 24 months and 70 percent at 36 months. Cariostat scores at each age were correlated with dmft at 36 months and with whether or not child was caries-free at 36 months. Cariostat scores at each age showed good validity (sensitivity + specificity) for whether or not child was caries-free at 36 months. These results indicated that caries activity test, Cariostat, was effective for predicting caries occurrence in young children.

Child, Preschool↗
PubMedDate not supplied

A study of baby bottle tooth decay and risk factors for 18-month old infants in rural Japan.

Caries risk factors in rural Japan were identified for 637 children age eighteen months. Oral examinations, behavioral risk questionnaires and caries activity tests (Cariostat) were utilized. Results indicated an overall 13.7 percent prevalence of decay and strong correlations between Cariostat and caries status. Of the behavioral risk factors, weaning from breast feeding was most closely related with caries status. All factors resulted in correct classifications of Cariostat score and caries status. These results suggest that a screening of high risk infants can be accomplished by using the questionnaire and Cariostat test.

Bottle Feeding↗
PubMedDate not supplied

Selective cerebral perfusion in patients with aortic aneurysms involving the aortic arch.

Patients with aortic arch aneurysms underwent surgery using a selective cerebral perfusion (SCP) method. For this purpose, a protocol for SCP was established on the basis of an animal experimental study. Our SCP procedure is performed at a perfusion rate of 6 ml/kg/min with the patient under deep hypothermia at 20 degrees C. The subject group in the current study included 36 patients, 28 men and eight women, ranging in age from 23 to 84 years (mean, 61). There were five operative deaths (13.9%). The mean cardiopulmonary bypass time was 288 minutes, and the mean aortic clamp time was 135 minutes. Mean SCP time was 89 minutes, exceeding 90 minutes in 17 cases. The mean blood pressure during SCP was 43 mmHg and oxygen saturation rate in the internal jugular vein was at least 90%. There was no definite production of lactate in the brain. Cerebral disorders considered to have been caused by SCP occurred in only two cases. It appears that cerebral metabolism can be maintained safely, and that our SCP method is useful during surgery for aortic arch aneurysms.

Adult↗
PubMedDate not supplied

Platelet dysfunction during cardiopulmonary bypass surgery. With special reference to platelet membrane glycoproteins.

Changes in platelet membrane glycoproteins (GPIb, GPIIb/IIIa, and GMP-140) were evaluated using flow cytometry after binding with monoclonal antibodies in 22 adult patients undergoing cardiopulmonary bypass (CPB) surgery. The amount of GPIb on platelets decreased significantly during CPB, reaching a minimum level of 64 +/- 26% of the pre CPB value at 120 min of CPB. There was no significant change in the amount of GPIIb/IIIa on platelets. In accordance with these changes, ristocetin induced agglutination decreased to 56.7 +/- 16.2% of the pre CPB value during CPB. However, there were no significant changes in ADP and collagen induced aggregation throughout the procedure. The number of the activated platelets expressing GMP-140 on their surfaces increased significantly during CPB. There was an upper limit to the amount of GMP-140 expression on each platelet in the circulating blood, suggesting that excessively activated platelets are removed from the circulation. The authors conclude that CPB reduces the amount of GPIb on platelets, which results in platelet dysfunction. In addition, removal of excessively activated platelets from the circulation may lead to thrombocytopenia after CPB.

Adult↗
PubMedDate not supplied

The effects of piezoelectric poly-L-lactic acid films in promoting ossification in vivo.

Uniaxially drawn poly-L-lactic acid (PLLA) films with piezoelectric properties were inserted onto the periosteum of rabbit tibiae, and the effect of the films in promoting ossification was investigated. We also evaluated the optimum method for PLLA film insertion to promote ossification, by comparing three different types of PLLA films which differed from each other in terms of the direction of their molecular orientation. Furthermore, the course of ossification following the film insertion was observed histologically. Drawn PLLA films promoted ossification to a greater extent than undrawn PLLA film. The effect of drawn PLLA films in promoting ossification was greatest when a shearing stress was applied at 45 degrees to the axis of orientation. The newly formed osteoid was observed at 1 week, and matured over 6 to 8 weeks following insertion. The insertion of piezoelectric PLLA films can promote ossification through their piezoelectric effect, and this seems to be clinically applicable.

Animals↗
PubMedDate not supplied

Epidemiologic study of 19-month-old Edmonton, Alberta children: caries rates and risk factors.

A random sample of 938 19-month-old Edmonton children and their parents/caretakers were studied. Parents were interviewed and children were examined. Specimens for a caries activity test were collected at the examination. Results indicated 25 percent of the children had moderate to high caries activity, as shown by the Cariostat, with 4.6 percent showing decalcification lesions and frank caries. Early caries (BBTD) were found to be related to bottle feeding practices, discomfort with allowing the child to cry, and with mother being foreign-born. Foreign-born status was associated with the above parenting practices. Preferences for preventive recommendations and other descriptive results were reported.

Adult↗