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Biomedical subjects

H Tamai

Publications and source records attributed to H Tamai.

At least 73 records · Page 4Linked to original sources
PubMed2000

Cyanamide-induced liver dysfunction after abstinence in alcoholics: a long-term follow-up study on four cases.

BACKGROUND: Cyanamide, an aversive agent widely used in Japan, is known to induce various degrees of hepatic lesion with ground-glass inclusion bodies. When cyanamide-treated alcoholics relapse into drinking, more severe inflammation develops in the liver. However, it is controversial whether progressive hepatic lesions develop in complete abstainers as a result of long-term cyanamide treatment. CASE REPORTS: Case 1: A 53-year-old male alcoholic received cyanamide treatment for 4.5 months and completely abstained without cyanamide treatment for 6 years. A liver biopsy shortly after abstinence showed extensive pericellular fibrosis, but a biopsy after 6 years showed very mild fibrosis. Case 2: A 43-year-old male alcoholic remained completely abstinent with cyanamide treatment for 5 years and complained of general fatigue. His serum transaminases were slightly elevated and hepatic hyperechogenicity was observed on ultrasonography. Only mild pericellular fibrosis was present in the liver biopsy specimen obtained shortly after abstinence, but after 5 years the second liver biopsy showed that thin septum-like fibrosis that formed portal-to-portal and portal-to-central linkage had developed and ground-glass hepatocytes had emerged extensively. Case 3: A 29-year-old female alcoholic complained of general fatigue and a slight fever after 1.5 years of abstinence with cyanamide treatment. Slight elevation of serum transaminases and hepatic hyperechogenicity were observed. The liver biopsy showed extensive ground-glass hepatocytes and thin septum-like fibrosis that formed portal-to-portal linkage. Case 4: A 61-year-old male alcoholic who remained completely abstinent while taking cyanamide for 3 years showed slight elevation of serum transaminases. Liver biopsy showed extensive ground-glass hepatocytes and extension of thin septum-like fibers from portal tract to the lobule. Ultrasonography revealed hepatic hyperechogenicity. CONCLUSION: In some abstainers who take cyanamide for several years, thin septum-like liver fibrosis progresses along with the emergence of ground-glass hepatocytes. Hepatic hyperechogenicity on ultrasonography and slight elevation of serum transaminases might erroneously lead to a diagnosis of hepatic steatosis without liver histology.

Adult↗
PubMed2000

Hepatic microvascular dysfunction in endotoxemic rats after acute ethanol administration.

BACKGROUND: A high concentration of ethanol is reported to cause hepatic microvascular dysfunction. However, little is known about the effect of ethanol on hepatic microcirculation in endotoxemic animals. The objective of this study was to determine whether endotoxemia enhances the hepatic microvascular dysfunction induced by acute ethanol administration. METHODS: Intravital videomicroscopy was used to monitor leukocyte recruitment, number of nonperfused sinusoids, and flow velocity of erythrocytes (RBC) labeled with fluorescein isothiocyanate (FITC) in the livers of male Wistar rats that were administered ethanol (20%, 3 g/kg; or 40%, 6 g/kg) from a gastric tube. Flow velocity of RBC in sinusoids was measured with an off-line velocimeter. Plasma tumor necrosis factor (TNF)-alpha levels were also measured. In some experiments, rats were injected with 2 mg/kg of lipopolysaccharides (LPS) intraperitoneally at 16 hr before the experiments, and the same protocol was performed. RESULTS: Although FITC-RBC velocity was initially increased by both 20% and 40% ethanol in control rats, it was reduced by only 40% ethanol at 60 min. In LPS-treated rats, the FITC-RBC velocity also was increased initially but was reduced at 60 and 30 min by 20% and 40% ethanol, respectively. Only 40% ethanol caused leukostasis in the pericentral region of control rats. In LPS-treated rats, however, leukostasis was noted in the midzonal and pericentral regions of liver after both 20% and 40% ethanol administration. Ethanol increased plasma TNF-alpha levels only in LPS-treated rats. CONCLUSIONS: These results suggest that LPS synergistically enhances ethanol-induced hepatic microvascular dysfunction and liver injury, especially in the midzonal region via coagulation, which may be mediated by TNF-alpha.

Animals↗
PubMed2000

Role of nitric oxide in endotoxin-induced hepatic microvascular dysfunction in rats chronically fed ethanol.

BACKGROUND: Nitric oxide (NO) appears to be involved in the pathogenesis of endotoxin-induced liver injury. However, little is known about how NO acts on the hepatic microcirculation, especially in alcohol-fed animals. We examined the roles of NO in endotoxin-induced hepatic microvascular dysfunction in control and ethanol-fed rats. METHODS: One lobe of the liver was observed with an intravital microscope. Flow velocity of fluorescein isothiocyanate-labeled erythrocytes in sinusoids was measured with an off-line velocimeter. Portal pressure and mean arterial pressure also were measured. RESULTS: After administration of endotoxin to control, the flow velocity decreased after 30 min. Portal pressure increased after 45 min. However, in ethanol-fed rats, both the flow velocity and portal pressure temporarily increased in the early phase. Thereafter, the flow velocity decreased and portal pressure increased. At 30 min after administration of the endotoxin, pretreatment with 10 mg/kg of an NO synthase inhibitor, NG-monomethyl-L-arginine (L-NMMA), enhanced the endotoxin-induced decrease in the velocity of erythrocytes in the midzonal region of both control and ethanol-fed rats. Although 0.5 mg/kg of L-NMMA enhanced the endotoxin-induced reduction of erythrocyte velocity in the midzonal region of ethanol-fed rats, L-NMMA enhanced the endotoxin-induced reduction of erythrocyte velocity in the pericentral region of control rats. At 60 min after the endotoxin administration, L-NMMA did not affect the endotoxin-induced decrease of erythrocyte velocity in either control or ethanol-fed rats. Although 10 mg/kg of L-NMMA increased mean arterial pressure both in control and ethanol-fed rats, 0.5 mg/kg of L-NMMA did not change mean arterial pressure in either control or ethanol-fed rats. CONCLUSIONS: These results suggest that NO is involved in endotoxin-induced hepatic microvascular dysfunction, which may contribute to the sequential liver injury, especially in alcohol-fed animals.

Animals↗
PubMed2000

[Anesthetic management for neonates with congenital cystic adenomatoid malformation].

We experienced two cases of congenital cystic adenomatoid malformation (CCAM) diagnosed by prenatal ultrasonography. The first case with type I CCAM underwent the resection of the right upper lobe 8 days after birth. Postoperative course was uneventful. The second case with type III CCAM developed non-immune hydrops, severe mediastinal shift, and polyhydroamnios at 29 weeks' gestation. At 30 weeks' gestation, cesarean section was performed. Immediately after birth, the resection of lung tumor for the neonate was performed. However, the neonate died on the 1st postoperative day.

Anesthesia, General↗
PubMed2000

[Combined intercostal nerve block and epidural anesthesia in a patient with severe aortitis syndrome].

A 74-year-old woman with aortitis syndrome was scheduled for mastectomy. Her left vertebral artery was totally occluded and left carotid arteries, left subclavia artery and bilateral common renal arteries were occluded. For anesthesia a catheter was inserted into the epidural space between T3 and T4. Lidocaine 80 mg (2%, 4 ml) was administered epidurally. Then intercostal nerve block was performed with bupivacaine 15 mg (0.5%, 3 ml) at T3 and T4 level. Local infiltration of lidocaine 50 mg (1%, 5 ml) was added. During the surgery, hemodynamics were stable and no neurological symptom was observed. Epidural anesthesia alone might be sufficient for anesthesia if higher concentration of local anesthetic was used. However, to avoid hemodynamic change, we used 1% lidocaine and added intercostal nerve block. We conclude that combined intercostal nerve block and epidural anesthesia was useful for a patient with severe aortitis syndrome in oder to monitor consciousness to detect cerebral ischemia and to avoid hemodynamic instability.

Aged↗
PubMed2000

[Predictors of prognosis after angioplasty in the unprotected left main coronary artery].

OBJECTIVES: The short-term and long-term predictors of outcome after coronary angioplasty in the unprotected left main coronary artery were investigated. METHODS: The procedure was performed in 122 consecutive patients for de novo lesions without myocardial infarction in our hospital between April 1986 and October 1998, including 16 emergency cases. Procedures were directional coronary atherectomy (73 patients), balloon angioplasty (31 patients), and stent implantation (18 patients). There were 101 males and mean age was 68 +/- 10 years. Follow-up angiography was performed in 98% of discharged patients, and all patients were clinically followed up for more than 1 year. Clinical and angiographic predictors of in-hospital and long-term outcome were evaluated. RESULTS: The in-hospital mortality was 5.7% (7 of 122 patients). Multivariate analysis revealed that more patients were admitted as emergency cases (57% vs 10%, p = 0.0088), with left ventricular ejection fraction < or = 35% (57% vs 22%, p = 0.029) and renal failure (43% vs 3%, p = 0.0004) finally died. Mean follow-up period was 3.5 years. Estimated survival rate was 77.1%, and cardiac-death free survival rate was 81.0% at 5 years by the Kaplan-Meier method. Univariate analysis showed that the predictors of cardiac death were emergency angioplasty, renal failure, decreased left ventricular ejection fraction, multivessel disease and unstable angina and/or congestive heart failure. Cox's regression model showed that renal failure (p = 0.0004) and multivessel disease (p = 0.0075) were significant predictors of long-term prognosis. CONCLUSIONS: Renal failure was the strongest predictor of outcome after unprotected left main coronary artery angioplasty.

Aged↗
PubMed1999

Hydrogenation of 1-Hexene and Hexadienes by Ultrafine Pd Particles Supported on the Surface of PrPO(4) Hollow Particles.

Novel fine polymer particles containing ultrafine Pd particles dispersed on the surface of core shell [core, poly(styrene-co-acrylic acid); shell, PrPO(4)]-type microspheres were prepared by the emulsifier-free emulsion polymerization of styrene with acrylic acid followed by the addition of PdCl(2) and a mixture of Pr(NO(3))(3) and NaH(2)PO(2). Pyrolysis of the resulting polymer particles at 900 degrees C provides organic polymer-free hollow particles (diameter, 473-586 nm) composed of Pd metal and PrPO(4). Hydrogenation of 1-hexene, trans-1,3-hexadiene, trans-1,4-hexadiene, and 1,5-hexadiene using the resulting Pd/PrPO(4) particles (reactant/Pd = 500 mol/mol) as catalyst revealed very high activity, especially for hydrogenations of 1-hexene and 1,5-hexadiene as compared with conventional Pd particles/Al(2)O(3) and Pd particles on powdered PrPO(4). Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Catheter-based reperfusion of unprotected left main stenosis during an acute myocardial infarction (the ULTIMA experience). Unprotected Left Main Trunk Intervention Multi-center Assessment.

The ULTIMA registry was a prospective, multicenter, international registry of 277 patients who underwent percutaneous coronary interventions of unprotected left main trunk stenosis. The 40 patients who underwent an emergency percutaneous left main intervention for acute myocardial infarction are the focus of this study. We compared the results of primary angioplasty with primary stenting, characterizing both the short-term (in-hospital) and long-term (12-month) outcomes. Of the 40 patients, 23 underwent primary angioplasty, whereas 17 underwent primary stenting. The angiographic success rate was an 88% for the cohort. The in-hospital death or coronary artery bypass grafting rate was 65% for the entire group, 74% for the percutaneous transluminal coronary angioplasty group (PTCA), and 53% for the stent group (p = 0.2). The in-hospital death rate was 55% for the entire cohort, 70% for the PTCA group, and 35% for the stent group (p = 0.1). The 12-month rate of death or bypass surgery was 83% and 58% for the PTCA and stent groups, respectively (p = 0.047). The 12-month survival rate was 35% and 53% for the PTCA and stent groups, respectively (p = 0.18). Bypass surgery was required in 6 patients in the PTCA group and 2 patients in the stent group (p = 0.07). Patients undergoing percutaneous interventions for unprotected left main myocardial stenosis during an acute myocardial infarction are critically ill; an initial percutaneous revascularization approach appears feasible and may be the preferred revascularization strategy. Primary stenting was associated with improved clinical outcomes.

Aged↗
PubMed1999

Preparation of Polymer Particles Coated with Hydroxyapatite.

Polymer particles coated with hydroxyapatite were prepared by treating Pd0 immobilized polystyrene-co-acrylic acid particles in aqueous CaCl2 and NaH2PO2 solutions. Hydroxyapatite coating took place at neutral to alkaline pH conditions, and the homogeneous growth of the hydroxyapatite layer on the surface of polymer particles was observed at relatively low temperature (30-50 degrees C). The thickness of the hydroxyapatite layer increased with reaction time. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Initial and long-term results of angioplasty in unprotected left main coronary artery.

Angioplasty of the unprotected left main coronary artery (LMCA) has been controversial. Although recent single-center studies suggest that new devices may change the situation, many questions and problems remain. Therefore, the results of unprotected left main coronary angioplasty of 175 procedures in 107 patients were analyzed to evaluate its feasibility and effectiveness. The treatment of the initial 107 cases included balloon angioplasty (39 cases, 36%), directional coronary atherectomy (53 cases, 50%), and stents (15 cases, 14%). They were divided into 3 major subgroups: (1) acute group (n = 14), in which LMCA angioplasty was performed in patients with acute myocardial infarction; (2) emergency group (n = 10); and (3) elective group (n = 83). In-hospital mortality was higher in the acute (35.7%) and emergency (40.0%) groups than in the elective group (3.6%; p <0.0001). Angiographic follow-up was routinely performed and the restenosis rate including in-hospital restenosis was 70% in the acute group, 37.5% in the emergency group, and 40% in the elective group (p = NS). The mean clinical follow-up period was 2.9 years, and the estimated 5-year survival rates of the acute and emergency groups were 50% and 48.2%, respectively. However the 5-year survival rate of the elective group was higher than that seen in the acute or emergency group (77.5%; p <0.05). Repeat LMCA angioplasty was performed in 37 of 68 patients with 8.8% mortality (38.5% of acute and emergency cases and 1.8% of elective cases). The results indicated that elective unprotected LMCA angioplasty is relatively feasible and effective under scheduled angiographic follow-up.

Adult↗
PubMed1999

Impact of tranilast on restenosis after coronary angioplasty: tranilast restenosis following angioplasty trial (TREAT).

BACKGROUND: Tranilast is an antiallergic drug that suppresses the release of cytokines such as platelet-derived growth factor, transforming growth factor-beta1, and interleukin-1beta and prevents keloid formation after skin injury. Treatment with this drug reduced the restenosis rate after percutaneous transluminal coronary angioplasty in a preliminary study. METHODS AND RESULTS: We conducted a multicenter, randomized, double-blind, placebo-controlled trial. A total of 255 patients with 289 lesions were randomly assigned to treatment with the oral administration of 600 mg/d tranilast, 300 mg/d tranilast, or a placebo for 3 months after successful angioplasty. Angiographic follow-up was done at 3 months, and a clinical follow-up examination was performed at 12 months. Two hundred ten (72.7%) lesions of 188 (73.7%) of the patients met the criteria and were eligible for the assessment of restenosis. The restenosis rates defined as >/=50% loss of the initial gain were 14.7% in the 600 mg/d tranilast group, 35.2% in the 300 mg/d tranilast group, and 46.5% in the placebo group (P <. 0001 for 600 mg/d tranilast vs placebo). The restenosis rates defined as percent diameter stenosis of >/=50% at follow-up were 17. 6% in the 600 mg/d tranilast group, 38.6% in the 300 mg/d tranilast group, and 39.4% in the placebo group (P =.005 for 600 mg/d tranilast vs placebo). CONCLUSIONS: The oral administration of 600 mg/d of tranilast for 3 months markedly reduced the restenosis rate after percutaneous transluminal coronary angioplasty.

Administration, Oral↗
PubMed1999

Effects of adjunctive balloon angioplasty after intravascular ultrasound-guided optimal directional coronary atherectomy: the result of Adjunctive Balloon Angioplasty After Coronary Atherectomy Study (ABACAS).

OBJECTIVES: This study was conducted to evaluate: 1) the effect of adjunctive percutaneous transluminal coronary angioplasty (PTCA) after directional coronary atherectomy (DCA) compared with stand-alone DCA, and 2) the outcome of intravascular ultrasound (IVUS)-guided aggressive DCA. BACKGROUND: It has been shown that optimal angiographic results after coronary interventions are associated with a lower incidence ofrestenosis. Adjunctive PTCA after DCA improves the acute angiographic outcome; however, long-term benefits of adjunctive PTCA have not been established. METHODS: Out of 225 patients who underwent IVUS-guided DCA, angiographically optimal debulking was achieved in 214 patients, then theywere randomized to either no further treatment or to added PTCA. RESULTS: Postprocedural quantitative angiographic analysis demonstrated an improved minimum luminal diameter (2.88 +/- 0.48 vs. 2.6 +/- 0.51 mm; p = 0.006) and a less residual stenosis (10.8% vs.15%; p = 0.009) in the adjunctive PTCA group. Quantitative ultrasound analysis showed a larger minimum luminal diameter (3.26 +/- 0.48 vs. 3.04 +/- 0.5 mm; p < 0.001) and lower residual plaque mass in the adjunctive PTCA group (42.6% vs. 45.6%; p < 0.001). Despite the improved acute findings in the adjunctive PTCA group, six-month angiographic and clinical results were not different. The restenosis rate (adjunctive PTCA 23.6%, DCA alone 19.6%; p = ns) and target lesion revascularization rate (20.6% vs. 15.2%; p = ns) did not differ between the groups. CONCLUSIONS: With IVUS guidance, aggressive DCA can safely achieve optimal angiographic results with low residual plaque mass, and this was associated with a low restenosis rate. Although adjunctive PTCA after optimal DCA improved the acute quantitative coronary angiography and quantitative coronary ultrasonography outcomes, its benefit was not maintained at six months.

Aged↗
PubMed1999

Diffuse cutaneous mastocytosis responding to cyproheptadine.

A 3-month-old male infant was referred to our department with a generalized brown, thickened leathery skin and blisters which had been present since birth; the blisters developed recurrently at sites of minor trauma, healing without scar formation, although Darier's sign was positive. Microscopically, biopsy specimens showed a dense dermal band-like infiltrate with mast cells, whereas a biopsy from a vesicle showed subepidermal bulla formation. Physical examination did not reveal any systemic involvement with mastocytosis and the patient was treated with cyproheptadine, which has considerable anti-serotonin activity and, interestingly, reduced the degree of blistering; this treatment might therefore be tried in other cases.

Cyproheptadine↗
PubMed1999

Risk factors for the development of Escherichia coli O157:H7 associated with hemolytic uremic syndrome.

Verotoxin-producing Escherichia coli (VTEC) O157:H7 is a major cause of hemorrhagic colitis that is often associated with the development of hemolytic uremic syndrome (HUS). In July, 1996, a severe mass outbreak of VTEC O157 infection occurred in Sakai city, Osaka. The present study investigates the risk factors which may contribute to the development of HUS in the early stages of the VTEC O157 infection. There was no significant difference between HUS-developed and non-HUS-developed groups with respect to sex, age, rates of clinical manifestations, such as fever, abdominal pain and bloody stool, use of anti-diarrheal agents, anti-motility agents, and/or antibiotic agents, and serum sodium concentrations at the early stage of VTEC O157 infection. Thus, these factors did not appear to be risk factors associated with the development of HUS. In contrast, leukocyte counts and C-reactive protein levels in the early stage of VTEC O157 infection were significantly higher in the HUS-developed group (P < 0.001), suggesting that these are risk factors associated with the development of HUS.

Bacterial Toxins↗