Search PubMed⌕ Search

Biomedical subjects

Y Nakazawa

Publications and source records attributed to Y Nakazawa.

At least 91 records · Page 5Linked to original sources

Prevention of hepatic artery thrombosis in pediatric liver transplantation.

Hepatic artery thrombosis after orthotopic liver transplantation is a serious complication, especially in children. We report our experience with intensive anticoagulant therapy during and after living-related liver transplantation in pediatric recipients. Twenty-four patients between 5 months and 15 years of age were studied. The mean diameter of the anastomosed hepatic arteries was 2.7 mm. The anticoagulant therapy consisted of low-molecular-weight heparin, antithrombin III concentrates, prostaglandin E1, fresh frozen plasma, and a protease inhibitor. The profiles of the coagulation and fibrinolytic systems were monitored by measuring several parameters, including plasma levels of thrombin-antithrombin III complex, antithrombin III, plasmin-alpha 2 plasmin inhibitor complex, fibrin degradation product D-dimer, tissue type-plasminogen activator, and plasminogen activator inhibitor-1. Acceleration of the coagulation system and delayed recovery of the fibrinolytic system were observed during the early postoperative days. The plasma level of antithrombin III activity was maintained within the normal range by the administration of antithrombin III concentrates. None of the recipients developed hepatic artery thrombosis. Children have been reported to be at a greater risk of developing hepatic artery thrombosis than adults due to the small diameters of their hepatic arteries and the postoperative hypercoagulable state. We believe that the intensive anticoagulation therapy described in this study, the main concept of which is the early correction of imbalance between the coagulant and anticoagulant systems, could become a model for the prevention of hepatic artery thrombosis in pediatric liver transplantation patients.

Adolescent↗

Pancreatic involvement in patients with Sjögren's syndrome and primary biliary cirrhosis.

Serum pancreatic enzyme activities, exocrine pancreatic function, and pancreatic ductal morphology were evaluated in patients with one or both of Sjögren's syndrome and primary biliary cirrhosis. Ten of 20 patients with Sjögren's syndrome (50%), 6 of 17 patients with primary biliary cirrhosis (35%), and 4 of 11 patients with both diseases (36%) had an elevated level of at least one pancreatic enzyme, including elastase-1, lipase, and trypsin. Diminished excretion of N-benzoyl-L-tyrosyl-para-aminobenzoic acid was observed in 3 of 17 patients with Sjögren's syndrome (18%), 4 of 16 with primary biliary cirrhosis (25%), and none of 7 with both diseases. Endoscopic retrograde pancreatograms demonstrated an abnormal pancreatic ductal configuration in 3 of 11 patients with Sjögren's syndrome (27%), 2 of 9 with primary biliary cirrhosis (22%), and 3 of 4 with both diseases (75%). Only minimal changes in branches of the pancreatic duct were observed in the pancreatogram. Finally, 9-30% of patients with Sjögren's syndrome and/or primary biliary cirrhosis had a mild and intermittent abdominal pain. These findings support the concept of a disease complex, "autoimmune exocrinopathy," in patients with Sjögren's syndrome, primary biliary cirrhosis, and chronic pancreatitis.

4-Aminobenzoic Acid↗

Effects of acetazolamide on the sleep apnea syndrome and its therapeutic mechanism.

Twenty male patients with sleep apnea syndrome were treated with acetazolamide (AZM), a carbonic anhydrase inhibitor. In 14 of the patient a significant decrease was found in the number of apnea, apnea index and % apnea time (percentage of time spent with apnea to the total sleep time) with improvement in sleep structure, clinical symptoms, such as insomnia, daytime excessive sleepiness and snoring. A significant decrease was also observed in arterial blood pH and HCO-3 in the 14 improved patients. On the other hand, no improvement occurred in the parameters of sleep apnea and sleep with AZM in the remaining six patients. Moreover, metabolic acidosis and an improvement in arterial blood gases did not occur with AZM in the six patients.

Acetazolamide↗

Reliability of the task-related component (P3b) of P3 event-related potentials.

Within session and between session reliabilities of the task-related component (P3b) of the P3 measures (amplitude, area and latency) and their habituation across eight sessions separated by 7-10 days, except for an interval of 1 month between the 6th and 7th sessions, were studied based on the difference waves, which were obtained by subtracting the ignored infrequent event-related potentials (ERP) from the target ERP elicited by a standard auditory oddball paradigm with eyes-open or eyes-closed conditions in 10 normal subjects. The within session reliabilities represented as Pearson correlation coefficients (r) were 0.57-0.66 for the three measures except for those for the latency and amplitude under the eyes-closed condition. The between session reliabilities expressed as intraclass correlation coefficients (R) ranged from 0.54 to 0.60 except for that for latency under eyes-closed conditions. Long-term habituation occurred within the first six sessions for the P3b amplitude and area, and dishabituation took place in the 7th session after an interval of 1 month, whereas no such phenomenon was observed for the P3b latency. Implications of the present results are discussed in terms of the clinical application of the P3 measures.

Adult↗

Prognosis of epilepsy withdrawn from antiepileptic drugs.

Antiepileptic drugs (AED) were discontinued in 55 epileptics who had been free from seizures treated with AED, in accordance with the following criteria and procedures. (i) A reduction in AED commences when patients have been free from seizures for at least 2 years and epileptic discharges have also disappeared in repeated electroencephalogram (EEG) recordings during that period. (ii) AED are gradually reduced if no relapse is seen in clinical seizures and epileptic discharges in EEG. (iii) As a rule at least 2 years are required as the interval from the onset of a reduction to the withdrawal of AED. Forty-three patients were followed up by a questionnaire and/or by telephone and the follow-up period from the withdrawal of AED to the survey ranged from 0.9 to 8.8 years; in 38 patients (88.4%) the period was longer than 2 years. No relapse of seizures was found in any of the 43 patients. The severity of epilepsy judged by the total number of frequency of seizures, the presence of neuropsychiatric complications, the combination of different types of seizures, and the duration of epilepsy from the seizure onset to the last seizure appeared not to be risk factors for the recurrence of seizure. Normal EEG was, however, considered to be an important prerequisite for a good prognosis.

Adolescent↗

Crosslines, fluorophores in the AGE-related cross-linked proteins.

We can summarize our results as follows: (1) A pair of fluorescent crosslines were isolated from the Maillard reaction mixture; (2) AGE-proteins contained crossline-like structures, and (3) crossline-like immunoreactivities were accumulated in renal tissues of diabetic rats. From these results we concluded that fluorophores in AGE proteins have crossline-like structures and we had the first indication that XLs could be markers for renal disorders.

Animals↗

[Diagnostic usefulness of myocardial SPECT with 123I-beta-methyl-iodophenyl pentadecanoic acid and 201Tl in unstable angina].

The purpose of this study is whether 123I-BMIPP detects a culprit lesion in patients with unstable angina. Twenty-six patients with unstable angina underwent 123I-BMIPP (BMIPP) and 201Tl (Tl) imaging at rest. BMIPP image was compared with Tl imaging. BMIPP imaging revealed defects or low uptake corresponding to myocardial ischemic areas predicted by coronary angiography in 19 (73.1%) of 26 patients. Tl imaging showed defects or low uptake corresponding to coronary angiographic findings in 14 (53.8%). BMIPP demonstrated significantly less uptake than Tl (p = 0.001). Severity of reduced BMIPP activity was greater than that of Tl (p < 0.001). We concluded that BMIPP imaging was excellent to detecting of culprit lesions in patients with unstable angina. BMIPP SPECT is a sensitive method for detecting myocardium exposed to transient schemia that cannot be detected by Tl imaging.

Aged↗

Effect of platelet-activating factor on cold-preserved liver grafts.

Platelet-activating factor (PAF) may play an important role in graft injury in liver transplantation. Livers excised from male Wistar rats were preserved in University of Wisconsin solution for 6 h and then perfused with Krebs-Henseleit solution containing vehicle (bovine serum albumin) or PAF. Impairment of parenchymal cells was assessed by reference to tissue adenosine triphosphate levels, oxygen consumption and alanine aminotransferase activity in the effluent. The effect on non-parenchymal cells was evaluated by measurement of purine nucleoside phosphorylase and alanine aminotransferase levels in the effluent. Administration of as little as 1.0 ng kg-1 PAF caused a significant decrease in adenosine 5'-triphosphate concentration and oxygen consumption (P < 0.05), although non-parenchymal cell injury was not affected. PAF can therefore cause liver graft dysfunction with hepatocytes as the main target, even in the absence of microcirculatory disturbance secondary to interaction between blood cells and endothelial cells.

Adenosine↗