PubMed Health⌕ Search

Biomedical subjects

S Yamagami

Publications and source records attributed to S Yamagami.

At least 37 records · Page 2Linked to original sources
PubMed2000

Isolated coronary ostial stenosis associated with coronary vasospasm.

A 50-year-old woman was brought to the emergency room in a preshock condition. An emergency coronary angiogram revealed 90% ostial stenosis of the left coronary artery with delayed distal filling. After intracoronary nitrate, the degree of stenosis was reduced to 75%; no other coronary lesions were evident. The patient was found to have hyperthyroidism and she became euthyroid after a 2-month regimen of methimazole. A follow-up coronary angiogram showed that the left coronary artery had 50% ostial stenosis without delayed distal filling. At the same time, an aortogram showed complete occlusion of the right subclavian artery in its proximal site, a slight dilatation of the truncus brachiocephalic artery, and a diffuse wall irregularity of the abdominal aorta, suggestive of Takayasu's arteritis.

Coronary Disease↗
PubMed2000

[Calcification in culprit lesions of coronary artery disease].

Coronary calcification, a type of coronary atherosclerosis, has recently been closely examined in clinical cardiology because its presence may influence the selection of interventional therapy. In addition, plaque instability is one of the most important factors in the mechanism of acute coronary syndrome, and calcium deposit is frequently detected in advanced lesions. However, little is known about the clinical significance of coronary calcification. The incidence of calcium deposits was investigated in the culprit lesions (culprit coronary calcification) of patients with serious coronary artery disease to discover any cardioprotective effect. Initial coronary angiography was performed in 179 consecutive patients with acute myocardial infarction with Q wave on electrocardiography (AMI group; male 139, female 40, mean age 60.2 +/- 10 yr) and in 119 consecutive patients with stable effort angina pectoris (SAP group; male 78, female 41, mean age 63.8 +/- 8 yr) for which balloon plasty or bypass surgery was necessary from 1990 to 1997. Culprit coronary calcification was defined positive if the calcification deposit was present cinefluoroscopically within 5 mm from the culprit point. The culprit point was defined as the narrowest point after successful intracoronary thrombolytic therapy or the latest point to be dilated during a balloon inflation in direct or rescue percutaneous transluminal coronary angioplasty in the AMI group, and the narrowest point of the culprit lesion in the SAP group. There was no statistical difference in clinical background between the 2 groups other than male dominance in the AMI group and high incidence of family history of ischemic heart disease in the SAP group (p < 0.05). Culprit coronary calcification in patients over 50 years old was less frequently positive in the AMI group than the SAP group (26% vs 66%, p < 0.005, respectively). In younger patients under 50 years old, the incidence of culprit coronary calcification was low (14-15%) in both groups. Culprit coronary calcification was frequently positive in the right or the left anterior descending coronary artery in the SAP group (p < 0.005). There was no incidental sex difference of culprit coronary calcification. This comparison suggests that if a plaque contains cinefluoroscopically visible calcification, it may be regarded as less vulnerable or having a history of chronic process of atherosclerosis which results in protecting plaque rupture.

Adult↗
PubMed2000

IL-6 antagonizes TGF-beta and abolishes immune privilege in eyes with endotoxin-induced uveitis.

PURPOSE: To determine the immunosuppressive status of aqueous humor (AqH) from mouse eyes afflicted with endotoxin-induced uveitis (EIU) and to identify the relevant cytokines responsible for immunomodulatory activity within EIU AqH. METHODS: Bacterial lipopolysaccharide (LPS) was injected into hind footpads of C3H/HeN mice; and AqH, collected at 6, 12, 24, and 48 hours, was evaluated for content of transforming growth factor (TGF)-beta, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, and interferon (IFN)-gamma and capacity to suppress anti-CD3-driven T-cell proliferation. Cytokine mRNA expression in iris-ciliary body (I/CB) was analyzed by RNase protection assays. RESULTS: During 6 to 24 hours after LPS injection, total TGF-beta levels in AqH increased even though the fluid lost its capacity to suppress T-cell activation. At this time, AqH contained high levels of IL-6, and I/CB contained high levels of IL-6 mRNA. When IL-6 was neutralized with specific antibodies, inflamed AqH reacquired its capacity to suppress T-cell activation, which correlated with high levels of TGF-beta. Coinjection of IL-6 plus antigen into the anterior chamber of the eye of normal mice prevented antigen-specific anterior chamber-associated immune deviation (ACAID). CONCLUSIONS: LPS-induced intraocular inflammation is associated with local production of IL-6, which robs AqH of its immunosuppressive activity, perhaps by antagonizing TGF-beta. The fact that IL-6 antagonized ACAID induction in normal eyes suggests that strategies to suppress the intraocular synthesis of IL-6 may reduce inflammation and restore ocular immune privilege.

Animals↗
PubMed1999

Comparison of the effects of dopamine D1 and D2 receptor antagonists on nerve growth factor mRNA expression.

Regulation of the expression of the nerve growth factor (NGF) gene has been reported previously to be mediated by the interaction of c-fos with an activator protein-1 (AP-1) binding site present in the first intron on the NGF gene. Using an RNase protection assay and in situ hybridization, we examined the effects of dopamine D1 and D2 receptor antagonists on NGF mRNA. Haloperidol (0.1-8 mg/kg) and (-)-sulpiride (10-100 mg/kg), induced NGF mRNA in a dose-dependent fashion in the hippocampus, piriform cortex, striatum and nucleus accumbens. The haloperidol (1 mg/kg)- and (-)-sulpiride (20 mg/kg)-induced NGF mRNA expression attained a maximum level 120 min after injection and returned to control levels 24 h later. Prior administration of the protein synthesis inhibitor cycloheximide blocked the haloperidol- and (-)-sulpiride-mediated induction of NGF mRNA. In contrast, R-(-)-8-chloro-2,3,4,5-tetrahydro-3,1-methyl-5-phenyl-11-3-benzyoepin e-7-ol (SCH23390) did not induce NGF mRNA expression in either a dose-dependent or time-dependent manner. Our previous studies have shown that haloperidol and (-)-sulpiride induce the expression of c-fos and c-jun mRNAs and increase their AP-1 DNA binding activities. Thus, the data suggest that neuroleptics induce NGF gene expression by increasing AP-1 DNA binding activity.

Animals↗
PubMed1999

Suppression of allograft rejection with anti-alphabeta T cell receptor antibody in rat corneal transplantation.

BACKGROUND: Anti-alphabeta T cell receptor monoclonal antibody (R73) has been reported to be a potent immunosuppressant. The suppressive effects of this antibody on allograft rejection after corneal transplantation are unknown. METHODS: Orthotopic rat penetrating keratoplasty was performed using Lewis rats as recipients and Brown Norway and Fisher rats as donors. The treated groups received R73 intraperitoneally until day 12 after the transplantation. In grafted rats with or without R73 treatment, cytokine expression of the aqueous humor, corneal-infiltrating cells, draining lymph nodes, and splenocytes was determined. Delayed-type hypersensitivity (DTH) responses were compared. RESULTS: All allografts in the untreated controls of Fisher-to-Lewis or BN-to-Lewis rat combinations were rejected within 14 days. In contrast, indefinite survival rates of the postoperative R73-treated group increased to 86% in the Fisher-to-Lewis and 23% in the Brown Norway-to-Lewis combinations, respectively. Interferon-y, interleukin (IL)-2 (T helper [Th]1), and IL-10 (Th2), but not IL-4 (Th2), expression of the eye and DTH responses in the control group were suppressed in the R73-treated group. Both IL-2 and IL-10 expression after mixed lymphocyte culture in the R73-treated group were significantly lower than those of the naive and untreated control group. CONCLUSIONS: alphabeta T cell receptor-targeted therapy prevents allograft rejection in rat corneal transplantation as evidenced by suppression of DTH responses. The cytokine profile after R73 treatment was characterized by low interferon-gamma, IL-2, and IL-10, and high IL-4 expression.

Animals↗
PubMed1999

Lymphocyte subset, lymphocyte proliferative response, and soluble interleukin-2 receptor in anorexic patients.

BACKGROUND: Despite a prominent malnourished state, anorexics are unexpectedly free from infection. Several studies have shown that the cell-mediated immunity of anorexics might be well preserved, but results are conflicting. METHODS: Lymphocyte subsets, lymphoproliferative response to phytohemagglutinin, and soluble interleukin-2 receptor (sIL-2R) were measured in 7 patients with anorexia nervosa restricting type (RAN), 6 with anorexia nervosa binge-eating/purging type (ANBP), and 8 controls (C). RESULTS: Compared with controls, significantly elevated percentage of CD4 and CD4/CD8 ratio in ANBP was found. Although there was no significant difference in lymphoproliferative response among the three groups, sIL-2R in RAN was significantly lower than that in the C group, but not in ANBP. CONCLUSIONS: Although detail mechanism still remains to be unknown, some kinds of compensatory mechanism for cell-mediated immunity is working, especially in chronic underweight anorexic patients.

Adult↗
PubMed1999

Altered body fat distribution after recovery of weight in patients with anorexia nervosa.

OBJECTIVE: This study investigated the changes in regional body composition such as bone mineral content, lean body mass, and fat mass in patients with anorexia nervosa before and after weight gain. METHODS: Body composition was measured before and after weight gain by dual photon absorptiometry in 21 female patients who met the DSM-III-R criteria. RESULTS: Soft mass of the pelvis, trunk, and upper and lower extremities in patients with anorexia nervosa was remarkably reduced to less than 70% of standard body weight. After restoring normal weight, soft mass of the pelvis and trunk increased remarkably and reached the levels of controls, but the soft mass in the upper and lower extremities remained below the control level. As a result, patients with anorexia nervosa demonstrated central obesity after weight recovery. DISCUSSION: We briefly discussed the cause of the altered fat distribution, such as central obesity, in patients with anorexia nervosa after weight recovery.

Adipose Tissue↗
PubMed1999

Differential production of MCP-1 and cytokine-induced neutrophil chemoattractant in the ischemic brain after transient focal ischemia in rats.

Chemokines have been shown to play an important role in leukocyte infiltration into ischemic lesions. Recently, the increased expression of monocyte chemoattractant protein-1 (MCP-1) and cytokine-induced neutrophil chemoattractant (CINC) was observed in experimental stroke models where infiltrated leukocytes were supposed to induce tissue injury, however, the protein level and time course of these chemokines have not been fully elucidated. Therefore, we analyzed the time-dependent production of MCP-1 and CINC in the rat brain after transient middle cerebral artery occlusion (MCAO) by means of specific enzyme-linked immunosorbent assay systems. The MCP-1 levels in the ipsilateral hemispheres increased from 6 h, peaked at 2 days, and thereafter gradually decreased. The peak MCP-1 concentration was 89.2+/-28.2 ng/g tissue wet weight (mean +/- SEM, n = 5, 49.3-fold greater than the contralateral value at the same time, P < 0.05), which is supposed to be high enough to exert its biological effects. In contrast, the maximum CINC concentration that corresponded to 2.9+/-0.7 ng/g tissue wet weight (mean +/- SEM, n = 5, 55.0-fold greater than the contralateral value at the same time, P < 0.05), was observed at 6 h. In addition, we confirmed the temporal profile of leukocyte subtypes that infiltrated into the ischemic brain, thus, neutrophil infiltration occurred at early stages (1-3 days), followed by massive infiltration of macrophages at later stages (2-7 days). These studies suggest that MCP-1 in cerebral ischemia actually plays a significant role in the migration of macrophages into the lesion and that the differential temporal production of these chemokines contributes to the regulation of infiltrated leukocyte subtypes.

Animals↗
PubMed1999

The chronic cell death with DNA fragmentation after post-ischaemic hypothermia in the gerbil hippocampus.

The long-term effects of post-ischaemic hypothermia are controversial. The purpose of this study was to examine the long-term effects of post-ischaemic hypothermia on neuronal survival in gerbils in terms of morphology and function. Hypothermia was induced at 32 degrees C for 4 h immediately after ischaemia. Examination was performed at 1 week and at 1 month after ischaemia. Post-ischaemic hypothermia prevented CA1 neuronal damage 1 week after ischaemia. At 1 month after ischaemic insult, however, the degree of the protective effect of post-ischaemic hypothermia was reduced in the lateral and medial CA1 areas. DNA fragmentation was also observed at 1 month. The errors in the 8-arm radial maze trial were increased at 1 month. These data may indicate that cells in the CA1 area are very vulnerable to ischaemia and die after post-ischaemic hypothermia, and that their death is associated with apoptosis.

Analysis of Variance↗
PubMed1999

Clinical characteristics in patients with anorexia nervosa and obsessive-compulsive disorder.

BACKGROUND: The purpose of this study was to assess clinical characteristics, including co-morbid personality disorders in patients with both anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) in comparison with age- and sex-matched patients with OCD. METHODS: Fifty-three female patients with AN were divided into two groups based on the presence or absence of a current diagnosis of OCD, as assessed by the Structured Clinical Interview for DSM-III-R Patient version (SCID-P). Twenty-one women (40 %) who met the DSM-III-R criteria for both AN and OCD were compared with 23 female patients with OCD, using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and the SCID Axis II disorders. RESULTS: There were no significant differences on the mean Y-BOCS severity scores between these groups. However, AN patients with OCD were significantly more likely than OCD patients to have obsessions with need for symmetry or exactness and ordering/arranging compulsions, whereas both aggressive obsessions and checking compulsions tended to be more frequently identified in OCD patients compared with AN patients with OCD. AN patients with OCD were significantly more likely than OCD patients to meet the criteria for obsessive-compulsive personality disorder (OCPD). CONCLUSIONS: These results suggest that there are some differential characteristics of the OCD symptomatology between these disorders, although many patients with AN manifest significant impairment from primary OCD symptoms with similar magnitude in severity to that found in OCD patients.

Adult↗
PubMed1999

Weight and shape concerns and dieting behaviours among pre-adolescents and adolescents in Japan.

The attitudes towards body weight and shape, desire for thinness and dieting behaviours were investigated in pre-adolescent and adolescent girls and boys (547 elementary school students, 615 junior high school students, and 470 senior high school students) aged 10-17 years in Osaka Prefecture, Japan, by a self-report questionnaire. Forty-eight per cent of 10-year-old females and 84% of 17-year-old females categorized themselves as 'fat' or 'too fat'. The fear of weight gain and desire for thinness was reported in 35% and 51% of 10-year-old girls, respectively, and increased progressively with ageing to 79% and 87% of 17-year-old girls. In contrast, these were reported by 20-30% of boys in the corresponding age groups. Some practices to be slim were found in 22% of the 10-year-old girls, and increased to 37% among the 17-year-old girls, whereas they were found in around 20% of the boys at each age. The practices to be slim were found in 32% of the girls who were 85-90% of the standard body weight (SBW) and in 14% of the girls less than 85% of the SBW. These results suggest that significant concerns about weight and shape and dieting behaviours are present in young Japanese girls and increase progressively with age. These results are compatible with those in Western society.

Adolescent↗
PubMed1999

Report of the annual statistical survey of the Japanese Society for Dialysis Therapy in 1996.

BACKGROUND: Nearly 170,000 patients were treated by maintenance renal replacement therapy (RRT) in Japan in 1996. The current status of Japanese patients on RRT might, in some way, be suggestive for patients on RRT in other countries. METHODS: The Japanese Society for Dialysis Therapy conducts a questionnaire survey of virtually every dialysis facility in Japan at the end of each year. Here we present the results of our survey of patients undergoing RRT as of the end of 1996, as well as five-year trends (1992-1996) in some of the data. RESULTS: The response rate was 99.8%. At the end of 1996, there were 167,192 patients on maintenance RRT in Japan (1,328 persons per million population). The numbers of patients on maintenance RRT continued to increase during the five-year period. The gross mortality rate for that period ranged from 9.4% to 9.7%. Cuprammonium rayon was the most commonly used material (24.0%) for dialyzer membranes, followed by cellulose triacetate (18.7%). Approximately 5.0% of hemodialysis (HD) patients had a prior history of surgical release of carpal tunnel. The longer the years on HD therapy, the greater the proportion of patients with a history of such an operation. The predialysis plasma beta 2-microglobulin concentration was highest in patients aged 30 to 45 years and declined slightly after the age of 45. There was no significant difference in the HbA1c level between continuous ambulatory peritoneal dialysis and HD patients, both in whom diabetes was the disease causing renal failure. Moreover, among HD patients with diabetes, there was a clear tendency for the HbA1c level to be higher when the normalized protein catabolic rate was higher. CONCLUSION: This report summarizes the latest results of the survey on Japanese patients on RRT.

Adult↗
PubMed1999

Sequence analysis of cDNA and genomic DNA, and mRNA expression of the medaka fish homolog of mammalian guanylyl cyclase C.

We isolated the cDNA and genomic DNA encoding a membrane guanylyl cyclase of medaka fish (designated as OlGC6), and determined their complete nucleotide sequences. The open reading frame for OlGC6 cDNA predicted a protein of 1,075 amino acids. Phylogenetic analysis indicated that OlGC6 is a member of the enterotoxin/guanylin receptor family. We also determined the partial genomic structure of the gene of another membrane guanylyl cyclase of medaka fish, OlGC2, which is a member of the natriuretic peptide receptor family. The intron positions relative to the protein-coding sequence are highly conserved in the intracellular domains of OlGC6, OlGC2, mammalian GC-A, and GC-E. Despite their divergent primary structures, some intron positions also seem to be conserved in the extracellular domains of different membrane guanylyl cyclase genes. Northern blot analysis demonstrated that an OlGC6 transcript of 3.9 kb is only present in the intestine, while reverse transcription (RT)-PCR analysis demonstrated that the OlGC6 transcript is present in the kidney, spleen, liver, pancreas, gallbladder, ovary, testis, brain, and eye. RT-PCR also demonstrated that OlGC6 is only expressed zygotically and that transcripts are present from 1 day after fertilization, i.e. long before the intestinal tissues begin to develop.

Amino Acid Sequence↗
PubMed1999

Effects of the thromboxane A2 receptor antagonist on platelet deposition and intimal hyperplasia after balloon injury.

Thromboxane A2 (TXA2) after vascular injury plays an important role in the process of restenosis. S-1452, a potent and selective TXA2 receptor antagonist, blocks the receptors of vascular smooth muscle cells (VSMC) as well as platelets. The purpose of this study was to determine whether S-1452 could reduce platelet deposition and intimal hyperplasia in vascular injury models. New Zealand White Rabbits (n = 41) were fed a 0.5% cholesterol diet. For the short-term study, eighteen rabbits after balloon injury of iliac artery were assigned to 3 groups; systemic administration of S-1452, single local administration of S-1452 using a local delivery balloon, and single local administration of saline solution. Platelet deposition in injured artery using 111In-labeled platelets was reduced by 50% in systemic administration and by 60% in local administration compared to saline infusion. For the long-term study, balloon injury of the iliac artery was performed 4 weeks after starting the 0.5% cholesterol diet. Twenty-three rabbits were classified into 4 groups; systemic administration of S-1452, oral placebo administration, single local administration of S-1452, and local administration of saline solution (control group). The platelet aggregation induced by U-46619 was significantly lower in the S-1452 group than in the control group. Systemic administration of S-1452 significantly reduced the intimal area (152 +/- 33 vs 735 +/- 135 microm2, p < 0.001) and number of cells in the intima (513 +/- 57 vs 993 +/- 57, p < 0.01) compared to controls. In contrast, a single local administration failed to reduce neointimal thickness. Systemic administration of S-1452 reduced intimal hyperplasia as well as platelet deposition in a rabbit injury model, but its single local administration inhibited only platelet deposition.

Angioplasty, Balloon↗
PubMed1999

Influence of rewarming conditions after hypothermia in gerbils with transient forebrain ischemia.

OBJECT: Recently, several studies have demonstrated that hypothermia has a beneficial effect on clinical outcome; however, it is difficult to determine the appropriate rewarming conditions in clinical use. The purpose of the present study was to examine the influence of rewarming conditions in gerbils with transient forebrain ischemia. METHODS: Ischemia was induced in the gerbils by a 5-minute bilateral common carotid artery occlusion, after which the animals were immediately subjected to moderate or deep hypothermia. After moderate hypothermia (30.5 degrees C for 4 hours) the animals were rewarmed over standard, fast, or slow time periods. After deep hypothermia (24 degrees C for 2 hours) the animals were rewarmed in a standard, fast, slow, or stepwise manner. Cerebral blood flow (CBF), extracellular glutamate, and lactate were monitored. Hippocampal CA I cell damage was assessed 7 days after induction of ischemia. In animals treated with moderate hypothermia, the rewarming rate had no influence on the number of surviving neurons. However, fast rewarming from deep hypothermia (to 37 degrees C for 30 minutes) failed to provide the neuroprotective effect of hypothermia. Furthermore, this group showed a poor recovery of CBF (p < 0.01) and, consequently, an increase in extracellular glutamate (p < 0.01) and lactate (p < 0.01) in the hippocampus. CONCLUSIONS: The results of this study indicate a transient uncoupling of CBF and cerebral metabolism during fast rewarming from deep hypothermia, whereas slow and stepwise rewarming periods were found to be useful for protection against uncoupling of CBF and cerebral metabolism during rewarming.

Animals↗
PubMed1999

Increase in orthotopic murine corneal transplantation rejection rate with anterior synechiae.

PURPOSE: To evaluate the immunologic effect of anterior synechiae (AS) in a murine model of corneal transplantation. METHODS: Orthotopic penetrating keratoplasty with 12 interrupted sutures was performed on C57BL/6 donor mice and BALB/c recipient mice without AS (AS- group). In contrast to suturing in the AS- group, 3 of the 12 sutures were placed to create AS (AS+ group). The average graft opacity scores and rejection rates of both groups were compared. Cytotoxic T-lymphocyte (CTL) reactions and delayed hypersensitivity (DH) were evaluated 3 weeks after transplantation. Corneal cytokine expression was evaluated. RESULTS: The opacity scores of the AS+ group were consistently greater than those of the AS- group, and the rejection rate of the AS+ group was significantly greater than that of the AS- group (86% versus 54%, P = 0.03). The AS+ group had significantly higher CTL activity compared with the AS- group. There was no significant difference in DH between the two groups. The cytokine expression pattern in the AS+ group became similar to that of the AS- group in which the grafts were rejected. CONCLUSIONS: These findings indicate that AS impairs ocular immune privilege by mediating CTL activity, but without intensifying the DH response. Therefore, AS is a critical risk factor in allograft rejection in a murine model of corneal transplantation.

Animals↗
PubMed1999

Differential chemokine gene expression in corneal transplant rejection.

PURPOSE: To evaluate the differential gene expression of chemokines after corneal transplantation and to determine the chemokines associated with allograft rejection. METHODS: Orthotopic mouse corneal transplantation was performed in two fully mismatched-strain combinations using C57BL/6 (H-2b) and BALB/c (H-2d) mice as recipients and BALB/c and C57BL/6 mice as donors. Normal nonsurgical eyes served as negative control specimens and syngeneic transplants (isografts) as control specimens for the alloimmune response. Chemokine gene expression in accepted and rejected allografts and appropriate control specimens was determined by a multiprobe RNase protection assay system. RESULTS: In eyes with rejected allografts, there was overexpression of regulated on activation normal T-cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, MIP-2, and monocyte chemotactic protein (MCP)-1 in both C57BL/6 and BALB/c recipients. In addition, C57BL/6 eyes with rejected allografts expressed very high levels of interferon-gamma-inducible protein of 10 kDa (IP-10) mRNA, in contrast to BALB/c eyes with rejected allografts, in which IP-10 expression remained very low. In contrast, lymphotactin gene expression increased only slightly in rejected allografts, and eotaxin mRNA, which was also detected in normal eyes, remained unchanged among isograft and allograft groups. T-cell activation gene (TCA)-3 mRNA was not detected in any of the assayed eyes. CONCLUSIONS: Increased expression of mRNA for select chemokines of the CXC (alpha) and CC (beta) families is associated with corneal allograft rejection. Significantly elevated IP-10 gene expression in high-rejector C57BL/6, but not in low-rejector BALB/c, hosts suggests that differential activation of chemokines may be related to differences in alloimmune reactivity observed among different murine strains.

Animals↗