Biomedical subjects

J Yamamoto

Publications and source records attributed to J Yamamoto.

At least 289 records · Page 16Linked to original sources

PubMed1990

Presentation of human minor histocompatibility antigens by HLA-B35 and HLA-B38 molecules.

Cytotoxic T lymphocyte (CTL) clones specific for human minor histocompatibility antigens (hmHAs) were produced from a patient who had been grafted with the kidneys from his mother and two HLA-identical sisters. Of eight CTL clones generated, four recognized an hmHA (hmHA-1) expressed on cells from the mother and sister 3 (second donor); two recognized another antigen (hmHA-2) on cells from the father, sister 2 (third donor), and sister 3; and the remaining two clones recognized still another antigen (hmHA-3) on cells from the father and sister 3. Panel studies revealed that CTL recognition of hmHA-1 was restricted by HLA-B35 and that of hmHA-2 and hmHA-3 was restricted by HLA-B38. The HLA-B35 restriction of the hmHA-1-specific CTL clones was substantiated by the fact that they killed HLA-A null/HLA-B null Hmy2CIR targets transfected with HLA-B35 but not HLA-B51, -Bw52, or -Bw53 transfected Hmy2CIR targets. These data demonstrated that the five amino acids substitutions on the alpha 1 domain between HLA-B35 and -Bw53, which are associated with Bw4/Bw6 epitopes, play a critical role in the relationship of hmHA-1 to HLA-B35 molecules. The fact that the hmHA-1-specific CTLs failed to kill Hmy2CIR cells expressing HLA-B35/51 chimeric molecules composed of the alpha 1 domain of HLA-B35 and other domains of HLA-B51 indicated that eight residues on the alpha 2 domain also affect the interaction of hmHA-1 and the HLA-B35 molecules.

Antigen-Presenting Cells↗

PubMed1990

Marked cardiac involvement in limb-girdle muscular dystrophy.

A 42-year-old man with limb-girdle muscular dystrophy who showed prominent cardiac involvement is described. He was treated for and diagnosed with dilated cardiomyopathy before admission. Initially, no overt feature of muscular dystrophy was evidenced, but serum enzymes were elevated. During the 2-year follow-up period, distinct features of muscular dystrophy appeared, and muscle biopsy confirmed the diagnosis. He was regarded as experiencing a sporadic occurrence. Because some patients diagnosed with and treated for dilated cardiomyopathy may have similar results, this form of muscular dystrophy should be recognized as occasionally associated with cardiac muscle disease.

Adult↗

PubMed1990

Psychiatric epidemiology in Korea. Part I: Gender and age differences in Seoul.

The most dramatic finding was the very high prevalence of alcohol abuse, using DSM-III criteria, among men in Seoul, Korea. The prevalence of other psychiatric disorders was lower than in St. Louis, Missouri. With the current biological emphasis in psychiatry, questions may be raised regarding the different prevalence rates of schizophrenia, affective disorders, and even alcoholism. The deficit of the aldehyde dehydrogenase isoenzyme 1 has been hypothesized to reduce the prevalence of alcohol abuse among Asians. Twenty-five percent of Koreans have been found to be deficient in the enzyme, but despite this their prevalence of alcohol abuse is higher than among Americans. Cultural issues are paramount in the much lower prevalence of alcohol abuse among women in Korea.

Adolescent↗

PubMed1990

Psychiatric epidemiology in Korea. Part II: Urban and rural differences.

This paper compares the findings in rural Korea and in the urban capital city of Seoul, Korea. In rural Korea 1966 subjects and in Seoul 3134 subjects were interviewed with the National Institute of Mental Health Diagnostic Interview Schedule. We found that the prevalence of psychiatric disorders, including alcohol dependence, was higher in rural Korea than in the urban setting. Comparing men and women, the prevalence of psychiatric disorders was higher in women. The exception was alcohol abuse/dependence, which was much higher among men, as was antisocial personality disorder. Comparison of prevalence by age groups showed that, in contrast to American studies, there was a tendency for prevalence to increase with increasing age. Alcohol abuse/dependence was much higher in rural Korea compared with St. Louis. Drug abuse/dependence was much higher in St. Louis. Other interesting similarities and differences are discussed.

Adolescent↗

PubMed1990

Discrimination of HLA-B5 crossreactive group antigens by human allospecific CTL clones.

Human CTL clones discriminating serologically closely related HLA-Bw52, B51, and B35, which belong to HLA-B5 crossreacting group (CREG), were established from peripheral blood lymphocytes by repeated in vitro stimulations. Five HLA-Bw52-specific CTL clones from an individual with HLA-B5 CREG antigens and four CTL clones from another individual with HLA-B51 were generated. The specificity of these CTL clones was ascertained by their lysis of EBV-transformed B cells with HLA-Bw52, but not those with HLA-B51 or B35, and Bw52-transfected Hmy2CIR cells but not HLA-B51 or B35 transfectants. Conversely HLA-B51-specific clones were generated from the HLA-B5 CREG-negative individual, as well as another individual with HLA-Bw52. Their specificity was determined in a similar fashion. Since HLA-B51 differed from HLA-Bw52 only by two amino acid substitutions on the alpha helical region of the alpha 1 domain, these results demonstrated that allospecific CTLs can be produced and discriminate the epitopes formed by the subtle difference in the structure of these HLA class I molecules. Furthermore, three HLA-B35-specific CTL clones were generated from the HLA-B5 CREG-negative individual that discriminated HLA-B35 from HLA-Bw52 and B51. Taken together these results demonstrated that human CTL clones could definitively discriminate the three serologically related HLA-B5 CREG specificities.

Clone Cells↗

PubMed1990

Drug resistance and R plasmids in Pasteurella multocida isolates from swine.

A total of 163 strains of Pasteurella multocida isolated from swine were examined for drug resistance and R plasmids. Strains resistant to sulfadimethoxine (Sar), ampicillin (Apr), streptomycin (Smr), kanamycin (Kmr), and chloramphenicol (Cpr) were found in 93.9, 1.8, 16.6, 1.2, and 10.4%, respectively. There were two patterns of drug resistance (Sar and SarCpr) in isolates from nasal cavities, and five patterns (Sar, SarSmr, SarSmrCpr, SarSmrApr, and SarSmrKmrCpr) in isolates from pneumonic lung specimens. Two isolates studied were proved to carry a nonconjugative R plasmid pJY2 or pJY8 with other unidentified plasmids, respectively. pJY2 (3.6 megadaltons) encoding resistance to SarSmr had one cleavage site for EcoRI or HindIII endonuclease and two sites for PstI endonuclease. pJY8 (5.5 megadaltons) encoding resistance to Sar SmrKmrCpr had one EcoRI site and two PstI sites.

Animals↗

PubMed1990

The distribution of mental illness found by DIS (Diagnostic Interview Schedule) among internal and orthopedic patients.

In order to understand how psychiatric problems are distributed in general medical departments, we used DIS (Diagnostic Interview Schedule). The subjects are 307 inpatients and outpatients in the Departments in Internal Medicine and Orthopedics of Fukuoka University Hospital, M Hospital and N Hospital. As a result, 53.4% of all the subjects showed some psychiatric problems. These are, in a descending order, tobacco dependence (30.0%), psychosexual dysfunction (14.3%), alcohol abuse/dependence (14.0%), major depressive episode (6.5%), organic brain syndrome (4.9%), obsessive-compulsive disorder (3.9%), dysthymic disorder (2.3%), panic disorder (2.0%) and others. Also, we discussed comparison between internal patients and neurotic patients who visited psychiatrists complaining of physical symptoms, and the incidence of DIS diagnoses in individual physical diseases.

Adolescent↗

PubMed1990

Feline leukemia virus infection as a potentiating cofactor for the primary and secondary stages of experimentally induced feline immunodeficiency virus infection.

Preexistent feline leukemia virus (FeLV) infection greatly potentiated the severity of the transient primary and chronic secondary stages of feline immunodeficiency virus (FIV) infection. Of 10 FeLV-FIV carrier cats, 5 died of experimentally induced FIV infection, compared with 2 deaths in 10 cats infected only with FeLV and 1 death in 7 cats infected only with FIV. FIV-infected cats with preexistent FeLV infections developed severe depression, anorexia, fever, diarrhea, dehydration, weight loss, and leukopenia 4 to 6 weeks after infection and were moribund within 2 weeks of the onset of signs, whereas cats infected only with FIV developed much milder self-limiting gross and hematologic abnormalities. Pathologic findings in dually infected cats that died were similar to those observed previously in cats dying from uncomplicated primary FIV infection but were much more widespread and severe. Coinfection of asymptomatic FeLV carrier cats with FIV did not increase the levels of FeLV p27 antigen present in their blood over that seen in cats infected with FeLV alone. The amount of proviral FIV DNA was much higher, however, in dually infected cats than in cats infected only with FIV; there was a greater expression of FIV DNA in lymphoid tissues, where the genome was normally detected, and in nonlymphoid tissues, where FIV DNA was not usually found. Dually infedted cats that recovered from the primary stage of FIV infection remained more leukopenic than cats infected with FIV or FeLV alone, and their CD4+/CD8+ T-lymphocyte ratios were inverted. One of these cats developed what was considered to be an opportunistic infection. It was concluded, therefore, that a preexistent FeLV infection in some way enhanced the expression and spread of FIV in the body and increased the severity of both the resulting transient primary and chronic secondary stages of FIV infection. This study also demonstrated the usefulness of the FIV model in studying the role of incidental infectious diseases as cofactors for immunodeficiency-causing lentiviruses.

Animals↗

PubMed1990

Changes of atrial natriuretic peptide and its messenger RNA with development and regression of cardiac hypertrophy in renovascular hypertensive rats.

We assessed the changes in atrial natriuretic peptide (ANP) and its messenger RNA (mRNA) levels in atria and ventricles in relation to hemodynamic factors during antihypertensive treatments in two-kidney, one-clip renovascular hypertensive rats (RHRs). Hypertension of 10-week duration caused a twofold increase in the left ventricular weight/body weight ratio, a significant increase in left ventricular end-diastolic pressure, and an eightfold increase in left ventricular ANP mRNA levels in RHRs, as compared with the levels in control rats. Uninephrectomy or 4 weeks of treatment with the converting enzyme inhibitor enalapril reduced the blood pressure to the control level, with the complete reversal of left ventricular hypertrophy, left ventricular end-diastolic pressure, and ANP mRNA levels. Four weeks of treatment with the arterial vasodilator hydralazine significantly, but not completely, reduced the high blood pressure, but it did not influence left ventricular hypertrophy, end-diastolic pressure, and ANP mRNA levels. The increased ANP synthesis observed in the right ventricles of RHRs also reverted to the control level by uninephrectomy or enalapril treatment, but not by hydralazine, with a time course similar to that of left ventricular ANP. In addition, uninephrectomy caused the left and right ventricular ANP and ANP mRNA levels of RHRs to fall to the levels of control rats as early as 1 week, despite persistent left ventricular hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Diabetes-induced alterations in atrial natriuretic peptide gene expression in Wistar-Kyoto and spontaneously hypertensive rats.

We investigated the effects of streptozotocin-induced diabetes on atrial natriuretic peptide (ANP) synthesis, hemodynamic parameters, blood volume, and histopathology, as well as the reversibility of such effects with insulin therapy in Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs). The biatrial ANP messenger RNA (mRNA) levels in the diabetic WKY rats increased by 16-17% compared with those in the age-matched WKY rats at 12 weeks after the onset of diabetes, whereas their ventricular ANP mRNA levels showed increases of 190% in left ventricles and 160% in right ventricles at 8 weeks. In the diabetic SHRs, the left atrial ANP mRNA levels increased by 36% compared with those in the age-matched SHRs, as early as 4 weeks after diabetes onset. Their ventricular ANP mRNA levels also showed 80-82% increases in left and right ventricles at 4 weeks. In proportion to changes in cardiac ANP synthesis, the biventricular end-diastolic pressures were significantly elevated at 8 weeks in the diabetic WKY rats and at 4 weeks in the diabetic SHRs. The blood volume significantly increased at 8 weeks in the diabetic WKY rats and remained higher thereafter, whereas it did not change in the diabetic SHRs throughout the experimental period. The left ventricular peak dP/dt was depressed in the 8-week diabetic SHRs, whereas in the diabetic WKY rats, its depression was observed at 12 weeks after diabetes onset. Histopathological studies showed that diabetic changes in ANP synthesis and hemodynamic parameters described above occurred before the cardiomyopathic histological changes. Cardiac ANP synthesis in the diabetic rats completely reverted to control levels after insulin therapy, accompanied by normalization of hemodynamic parameters. The present study indicates that 1) ANP synthesis is significantly augmented in the streptozotocin-induced diabetic rat compared with that in the normal rat, and the combination of diabetes and hypertension produces an earlier and greater effect in stimulating cardiac ANP synthesis than does either disease alone; 2) an elevation in the intraventricular filling pressure that occurs before observable cardiomyopathic histopathological alterations might be involved partially in the augmented ANP synthesis; and 3) the reversibility with insulin therapy suggests that the streptozotocin-induced alterations observed in cardiac ANP synthesis and hemodynamics result from insulin-deficient diabetes mellitus, not from cardiac toxicity of streptozotocin.

Animals↗

PubMed1990

Synthesis of valproyl-2-pyrrolidinone and its evaluation as a cognitive drug with the ability to modulate acidic amino acids in the brain.

A new pyrrolidinone derivative, valproyl-2-pyrrolidinone (VP), was synthesized, followed by evaluation as a cognitive drug. VP gave rise to a significant protective effect against cerebral anoxia together with a potent prolongation of latency time for the reversal of scopolamine induced transient disruption of the memory of a passive avoidance response in rats. The quantitative experiment using HPLC demonstrated a significant reduction of hippocampal aspartate (Asp) and glutamate (Glu) following the intraperitoneal administration of VP at a dose of 300 mg/kg.

Administration, Oral↗

PubMed1990

Amino acids and peptides. XXVIII. Synthesis of peptide fragments related to eglin c and studies on the relationship between their structure and effects on human leukocyte elastase, cathepsin G and alpha-chymotrypsin.

Various peptide fragments related to eglin c, which consists of 70 amino acid residues, were synthesized by a conventional solution method and their inhibitory effects on leukocyte elastase, cathepsin G and alpha-chymotrypsin were examined. Among them, H-Arg-Glu-Tyr-Phe-OMe (eglin c 22-25) and H-Ser-Pro-Val-Thr-Leu-Asp-Leu-Arg-Tyr-OMe (eglin c 41-49) inhibited cathepsin G and alpha-chymotrypsin but not leukocyte elastase, while H-Thr-Asn-Val-Val-OMe (eglin c 60-63) inhibited leukocyte elastase but not cathepsin G or alpha-chymotrypsin, although eglin c potently inhibited leukocyte elastase, cathepsin G and alpha-chymotrypsin. These results indicated that the interaction sites of eglin c with leukocyte elastase, cathepsin G and alpha-chymotrypsin might be different.

Amino Acid Sequence↗

PubMed1990

Synthesis of a heptacontapeptide corresponding to the entire amino acid sequence of eglin C.

A heptacontapeptide corresponding to the entire amino acid sequence of eglin c was synthesized by the conventional solution method using a minimal protecting method. The synthetic eglin c exhibited a symmetrical single peak on HPLC at the same retention time as an authentic eglin c, and had the same inhibitory activity against human leukocyte elastase, cathepsin G and alpha-chymotrypsin (Ki = 6.0 x 10(-9) M, 5.5 x 10(-9) M and 2.5 x 10(-9) M, respectively) as N alpha-acetyl-eglin c synthesized genetically (Ki = 5.1 x 10(-9) M, 1.5 x 10(-8) M and 2.2 x 10(-9) M, respectively).

Amino Acid Sequence↗

PubMed1990

Amino acids and peptides. XXIX. Synthesis of peptide fragments related to active center of eglin c and studies on the relationship between their structure and their inhibitory activity against cathepsin G and alpha-chymotrypsin.

H-Ser-Pro-Val-Thr-Leu-Asp-Leu-Arg-Tyr-OMe, corresponding to the sequence 41-49 of eglin c, inhibited human leukocyte cathepsin G and alpha-chymotrypsin. In order to gain further insight into the relationship between the structure and the inhibitory activity against cathepsin G and alpha-chymotrypsin, peptide fragments related to the above nonapeptide were synthesized by a conventional solution method and their inhibitory activities were examined. The smallest peptide which exhibited inhibitory effects on the above enzymes was H-Pro-Val-Thr-Leu-OMe, corresponding to the sequence 42-45 of eglin c.

Amino Acid Sequence↗

PubMed1990

Coronary hemodynamics in diabetic spontaneously hypertensive rats.

We investigated the coronary hemodynamics in conscious spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats 4 and 20 weeks after streptozotocin or vehicle injection. The hemodynamic parameters were measured at rest and during maximal coronary vasodilation with dipyridamole. Streptozotocin, 40 or 60 mg/kg, produced moderate or severe diabetes in both strains, but resulted in a mortality of 11.3 or 40.8% in SHR alone. The left and right ventricular weights were decreased with no change in their ratios to body weight in both strains. Severely diabetic SHR and WKY revealed hypotension, bradycardia, an increased cardiac index and decreased total peripheral resistance index at both weeks. Moderately diabetic SHR revealed similar changes except for an unaltered cardiac index. Short-term severely diabetic SHR alone displayed an increased basal bi-ventricular coronary flow (per unit mass). The maximal coronary flow was unaltered in any group by diabetes. The left ventricular transmural flow distribution was also unaltered in any group. However, severe diabetes in SHR diminished a coronary flow reserve (maximal minus basal flow) of the left ventricle at 4 weeks, and that of both ventricles at 20 weeks. Thus, the severity and duration of diabetes had a strain-related influence on the systemic and coronary hemodynamics, with deaths and a reduced coronary flow reserve in SHR alone. The minimal coronary vascular resistance in both ventricles (per unit mass) showed no increase in each group by diabetes, suggesting no overall decrease in functional cross-sectional area of the coronary vasculature.

Animals↗

PubMed1990

[111In-antimyosin scintigraphy on acute myocardial infarction].

Indium-111 antimyosin (InAM) scintigraphy was performed in 17 patients with acute myocardial infarction (on 15 +/- 6 days from the onset). The degree of myocardial uptake was classified into 3 groups. They were ranged from low intensity as in bone marrow to high intensity as in liver. All of 17 cases showed positive myocardial uptake including low intensity. The locations of infarction judged by InAM were in agreement with those by electrocardiography, coronary angiography (CAG), and 99mTc-pyrophosphate scintigraphy (PYP, performed on 5 +/- 2 days from the onset). In 5 cases, the uptake of InAM showed doughnuts or diffuse pattern which was occasionally observed on PYP. These cases showed myocardial uptake of 4th degree of Parkey's classification with doughnuts-like pattern on PYP, and showed involvement of left anterior descending artery on CAG. In some cases, the extent of myocardial uptake on InAM did not agree with those on PYP.

Aged↗

PubMed1990

Pharmacological studies of 6-amidino-2-naphthyl 4-[(4,5-dihydro-1H-imidazol-2-yl)amino]benzoate dimethanesulfonate. Effects on experimental pancreatitis.

The effects of FUT-187 (6-amidino-2-naphthyl 4-[(4,5-dihydro-1H-imidazol-2-yl)amino]benzoate dimethanesulfonate, CAS 103926-82-5), a novel synthetic protease inhibitor, were examined in experimental rat and canine models of pancreatitis. 1. FUT-187 significantly increased the survival of rats with trypsin- and phospholipase A2-induced pancreatitis in a dose-dependent manner (10-100 mg/kg, p.o.). 2. FUT-187 decreased plasma enzymatic activity reflecting the degree of pancreatitis in rats with ethionine-induced pancreatitis, and showed a tendency to ameliorate histopathological changes in the pancreas (10-100 mg/kg p.o.). 3. FUT-187 (10 mg/kg) produced an obvious improvement of various biochemical parameters of pancreatitis and also reduced histopathological changes in the pancreas in animals with experimental pancreatitis produced by the closed duodenal loop method. In addition, FUT-187 significantly increased the survival of dogs when given by direct administration into the lumen of the closed duodenal loop. The therapeutic effects of FUT-187 in experimental pancreatitis were nearly equal in most instances to those of camostat mesilate. Thus, FUT-187 would appear to be an effective new agent for the treatment of pancreatitis.

Acute Disease↗

PubMed1990

[Medical and surgical treatment for patients with dissecting aneurysms of the aorta].

The medical and surgical treatment of 96 patients of dissecting aneurysms was reviewed. There were 42 patients with Stanford type A dissecting aneurysms, 19 of whom received medical treatment and 23 of whom had surgical treatment. Among 54 patients with Stanford type B dissecting aneurysms, 24 had medical and 30 had surgical treatments. The treatment results and the long-term outcomes were studied using the Kaplan-Meier method, categorizing the subjects in non-survivor (in-hospital) and survivor groups. The results indicated that those with surgical treatment had a higher survival rate (75%) in the early post-operative course, for both type A and type B aneurysms. However, the long-term outcome of the survivor group was not different between type A and type B aneurysms regardless of type of treatment. Fifty-six percent of cases with type A aneurysms with serious complications survived by medical treatment alone, and no intimal tears were visualized on angiogram. Therefore, it was suggested that, in patients who had no angiographically defined intimal tears in the acute phase, medical treatment may be more effective, even for type A dissecting aneurysms.

Aortic Dissection↗