Biomedical subjects

S Miyazaki

Publications and source records attributed to S Miyazaki.

At least 55 records · Page 3Linked to original sources

PubMed2001

Lipoolygosaccharide indirectly enhances inflammatory lesions in lungs as a primary infection site by non-encapsulated and type B Haemophilus influenzae through production of cytokines.

We investigated the role of cytokines in differences in histopathologic changes in the lung between bronchopneumonia caused by non-encapsulated Haemophilus influenzae strain 770235f(0)b(0)and systemic disease caused by type b H. influenzae strain 770235f(0)b(+). Tumour necrosis factor-alpha (TNF-alpha), interleukin-(IL)-6 and IL-1 beta levels in bronchoalveolar lavage fluid (BALF) samples of mice infected with strain 770235f(0)b(0)were higher than in those infected with strain 770235f(0)b(+)until 24 h post-infection. Serum IL-6 rapidly increased in strain 770235f(0)b(0)infection after 72 h post-infection. Serum TNF-alpha level in strain 770235f(0)b(0)infection appeared earlier than in strain 770235f(0)b(+)infection. IL-1 beta production in strain 770235f(0)b(+)infection was later than in strain 770235f(0)b(0)infection. Moreover, a biphasic concentration pattern of TNF-alpha and IL-6 was noted in BALF of mice with strain 770235f(0)b(0)infection.

Animals↗

PubMed2001

Regioselective nucleophilic additions to cross-conjugated dienone system bearing beta-fluorine: a versatile approach to highly substituted 2-cyclopentenones.

[reaction: see text] 3-Fluoro-5-methylene-2-cyclopentenone is treated with appropriate nucleophiles and Lewis acids to undergo regioselective 1,2-addition, exocyclic 1,4-addition, and endocyclic 1,4-addition, leading to 3-substituted 4-methylene-2-cyclopentenones, 5-substituted 3-fluoro-2-cyclopentenones, and 3-substituted 5-methylene-2-cyclopentenones in good yields, respectively.

Cyclopentanes↗

PubMed2001

Clinical and biologic characteristics for recurring neuroblastoma at mass screening cases in Japan.

BACKGROUND: It is said that most cases detected by neuroblastoma mass screening at 6 months of age tend to have a favorable clinical course after a surgical resection either with or without mild chemotherapy. However, a few cases have an unfavorable outcome. In the current study, the authors analyzed the clinical and biologic characteristics for recurring neuroblastoma in mass screening cases. METHODS: In 245 cases detected through mass screening in the Kyushu area in Japan, the clinical data and biologic features (N-myc status, DNA ploidy, Shimada histology, neuron-specific enolase (NSE), ferritin) were investigated, whereas, in particular, the data for recurring cases also were analyzed. RESULTS: Of 245 cases, 28 tumors had one or more biologically unfavorable prognostic factors, and 6 patients experienced recurrence. Three of the six patients with recurring disease underwent a complete resection of the primary tumor, whereas three cases had undergone an incomplete resection of the tumor. Regarding the initial chemotherapy, three cases received mild chemotherapy, two cases received no chemotherapy, and one case had high-dose multidrug chemotherapy. Regarding biologic prognostic factors, four of six cases with recurring disease had one or more unfavorable factors, whereas two cases had no unfavorable factors. Regarding the outcome after recurrence, four cases are CR, one case has a stable residual tumor, and one case died of disease with N-myc amplification. CONCLUSIONS: Most neuroblastomas detected by mass screening at 6 months of age have biologically favorable factors. However, approximately 10% of the cases had one or more unfavorable factors and thus might have a higher risk of recurrence than the patients with no unfavorable factors. Conversely, some cases with recurring disease had no unfavorable factors; however, the reason for this is still unclear. A long-term follow-up for mass screening cases is important, and it also might be necessary to research the established biologic factors and identify other new prognostic factors.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2001

Comparison of in situ gelling formulations for the oral delivery of cimetidine.

Three liquid formulations with in situ gelling properties have been assessed for their potential for the oral delivery of cimetidine. The formulations were dilute solutions of: (a) enzyme-degraded xyloglucan, which form thermally reversible gels on warming to body temperature; (b) gellan gum and; (c) sodium alginate both containing complexed calcium ions that form gels when these ions are released in the acidic environment of the stomach. The in vitro release of cimetidine from gels of each of the compounds followed root-time kinetics over a period of 6 h. Plasma levels of cimetidine after oral administration to rabbits of each of the formulations were compared with those resulting from administration of a commercial cimetidine/alginate suspension with an identical drug loading. In vivo release characteristics of each of the in situ gelling formulations were similar to those of the commercial preparation.

Absorption↗

PubMed2001

Monozygotic twins incompletely concordant for narcolepsy.

BACKGROUND: Among 15 monozygotic twin pairs described in the literature, only four pairs were considered to be concordant. There is no detailed report of HLA-DRB1*1501/DQB1*0602 positive monozygotic twins concordant for narcolepsy, with marked difference in the age of onset. METHODS: We compared a pair of female narcoleptic twins clinically. RESULTS: Diagnosis of narcolepsy and monozygosity of the twins were confirmed. The second-born twin demonstrated a typical course of narcolepsy, whereas the first-born twin had a very late onset of recurrent daytime sleep episodes at age 45 and cataplexy at age 50 years, which was apparently triggered by chronic emotional stresses and sleep insufficiency. CONCLUSIONS: The atypical course of narcolepsy in the first-born twin supports the multifactorial model for the development of narcolepsy. It was noted that cataplexy was preceded by sustained polyphasic sleep conditions. Our observation implies that the unaffected co-twins in discordant pairs could develop narcolepsy in stressful situations later in their lives.

Cytochrome P-450 Enzyme System↗

PubMed2001

Usefulness of serum troponin T levels on day three or four in predicting survival after acute myocardial infarction.

The appearance of serum troponin T (tn-T) on day 1 after acute myocardial infarction (AMI) strongly depends on coronary reperfusion. In contrast, the kinetics of tn-T release after day 1 after AMI are unaffected by the reperfusion status, and reflect the degradation of myofilaments in irreversibly damaged cells. However, it is not known whether serum tn-T levels after day 1 after AMI can be used to predict the long-term outcome. The purpose of this study was to elucidate the prognostic value of determining the tn-T level on day 3 or 4 after AMI. Serum tn-T levels on day 3 or 4 after AMI were measured in 121 patients (92 men and 29 women, mean age 65 years). Mean follow-up period was 526 days. There were 12 deaths (9 cardiac and 3 noncardiac) during the follow-up period. By Kaplan-Meier analysis, patients with tn-T levels higher than the median level (6.9 ng/ml) had a significantly higher mortality rate than those with submedian levels (p <0.01). By multivariate Cox proportional-hazards regression analysis, the serum tn-T level was an independent predictor of the long-term outcome after AMI (p <0.01). Futhermore, in patients with a first AMI, the serum tn-T level exhibited a significant negative linear correlation with left ventricular ejection fraction assessed 4 weeks after AMI (r = -0.48, p <0.001). Increased serum tn-T levels on day 3 or 4 after AMI are a powerful noninvasive predictor of poor long-term prognosis, reflecting residual left ventricular function after AMI.

Aged↗

PubMed2001

Breakage and fusion of the TEL (ETV6) gene in immature B lymphocytes induced by apoptogenic signals.

TEL-AML1 fusion resulting from the t(12;21)(p13;q22) is one of the most common genetic abnormalities in childhood acute lymphoblastic leukemia. Recent findings that site-specific cleavage of the MLL gene can be induced by chemotherapeutic agents such as topoisomerase-II inhibitors suggest that apoptogenic agents can cause chromosomal translocations in hematopoietic cells. This study demonstrates a possible relationship between exposure to apoptogenic stimuli, TEL breaks, and the formation of TEL-AML1 fusion in immature B lymphocytes. Short-term culture of immature B cell lines in the presence of apoptogenic stimuli such as serum starvation, etoposide, or salicylic acid induced double-strand breaks (DSBs) in intron 5 of the TEL gene and intron 1 of the AML1 gene. TEL-AML1 fusion transcripts were also identified by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis in cell lines treated by serum starvation or aminophylline. DSBs within the TEL gene were also associated with fusion to other unknown genes, presumably as a result of chromosomal translocation. We also examined 67 cord blood and 147 normal peripheral blood samples for the existence of in-frame TEL-AML1 fusion transcripts. One cord blood sample (1.5%) and 13 normal peripheral blood samples (8.8%) were positive as detected by nested RT-PCR. These data suggest that breakage and fusion of TEL and AML1 may be relatively common events and that sublethal apoptotic signals could play a role in initiating leukemogenesis via the promotion of DNA damage.

Aminophylline↗

PubMed2001

Molecular analysis of Japanese patients with Rett syndrome: Identification of five novel mutations and genotype-phenotype correlation.

Rett syndrome is an X-linked dominant neurodevelopmental disorder that affects females almost exclusively. The recent identification of mutations of the methyl-CpG-binding protein 2 gene (MECP2) in patients with RTT, encouraged us to analyze the gene in 37 Japanese patients divided into classical RTT (14 cases), variant RTT (13 cases), and mentally retarded patients with Rett-like features (10 cases). Mutations in MECP2 were identified from most of the patients with classical and variant RTT (25 of 27 cases). Six reported common mutations were detected in 17 cases, and rare single nucleotide substitutions were found in 3 patients. In addition, one insertion mutation (1189insA) and four deletion mutations including one double deletion mutant (451delG, 100del4, 1124del53 and 881del289 plus 1187del8) were newly identified. In the 10 mentally retarded patients with Rett-like features, however, no mutation was detected in the coding region of MECP2. The finding of MECP2 mutations in 92.5% of patients with RTT indicates that RTT fulfilling the diagnostic criteria are due to genetic alteration.

Amino Acid Substitution↗

PubMed2001

Long-term outcome of treatment with protocols AL841, AL851, and ALHR88 in children with acute lymphoblastic leukemia: results obtained by the Kyushu-Yamaguchi Children's Cancer Study Group.

We analyzed the long-term outcome and late effects of treatment in 187 patients with childhood acute lymphoblastic leukemia (ALL) diagnosed between 1984 and 1990. Overall survival and event-free survival rates were 68.2% +/- 3.7% and 63.2% +/- 3.6% at 15 years, respectively. Of 55 patients who relapsed after achieving the first complete remission (CR), only 17.4% were rescued by salvage therapy. The advantage of stem cell transplantation over chemotherapy was observed only in those patients with bone marrow relapse during therapy. The SD for score height in patients maintaining the first CR significantly decreased at the time of final follow-up compared with that at diagnosis: 0.059 to -0.800 (P < .0001). The decrease was remarkable in patients younger than 5 years at diagnosis. Other late effects included mild liver dysfunction in 18% and hepatitis C virus infection in 9%. Congestive heart failure was observed in only 2.9% of patients despite the high cumulative dose of daunorubicin (450 mg/m2). Although the survival rates of patients on our protocols were comparable to those of other study groups, some modification, including reduction in dose of cranial irradiation and/or anticancer drugs, should be considered to reduce late adverse effects in survivors of childhood ALL.

Adolescent↗

PubMed2001

Expression of prostaglandin H synthase-2 in human brain tumors.

Numerous studies have demonstrated that prostaglandin H synthase-2 (PHS-2) is involved in gastrointestinal carcinogenesis, and that nonsteroidal anti-inflammatory drugs (NSAIDs), which inhibit PHS, can reduce the risk of colon cancer. In brain tumors, elevated prostaglandin production and its correlation to anaplastic grade of gliomas have been demonstrated. To determine whether the increased prostaglandin production is due to enhanced expression of PHS-2 and whether the up-regulation of PHS-2 has any correlation to histopathological findings in brain tumors, we evaluated the profile of PHS expression in several human glioma cell lines and surgical specimens from patients with various types of brain tumors. In glioma cell lines, five out of six cell lines showed constitutive expression of PHS-2, whereas PHS-1 was weakly expressed in all of them. All surgical specimens, except an ependymoma, which expressed both isozymes equally, expressed PHS-2 mRNA predominantly. Immunohistochemistry of various types of brain tumors, including six glioblastomas, nine astrocytomas, six meningiomas, five medulloblastomas, four craniopharyngiomas, three ependymomas, three neurinomas, two oligodendrogliomas, two malignant lymphomas, two dysembryoplastic neuroepitherial tumors and one metastatic brain tumor showed PHS-2 staining in most cases. In gliomas, astrocytomas (grade 2 and 3) were strongly stained, but the staining intensity of glioblastomas was relatively weak. Meningiomas and a metastatic brain tumor were also strongly stained. Our data thus suggest that most brain tumors express PHS-2, which may also play a role in tumorigenesis in the brain.

Adolescent↗

PubMed2001

Transient left ventricular apical ballooning without coronary artery stenosis: a novel heart syndrome mimicking acute myocardial infarction. Angina Pectoris-Myocardial Infarction Investigations in Japan.

OBJECTIVES: To determine the clinical features of a novel heart syndrome with transient left ventricular (LV) apical ballooning, but without coronary artery stenosis, that mimics acute myocardial infarction, we performed a multicenter retrospective enrollment study. BACKGROUND: Only several case presentations have been reported with regard to this syndrome. METHODS: We analyzed 88 patients (12 men and 76 women), aged 67 +/- 13 years, who fulfilled the following criteria: 1) transient LV apical ballooning, 2) no significant angiographic stenosis, and 3) no known cardiomyopathies. RESULTS: Thirt-eight (43%) patients had preceding aggravation of underlying disorders (cerebrovascular accident [n = 3], epilepsy [n = 3], exacerbated bronchial asthma [n = 3], acute abdomen [n = 7]) and noncardiac surgery or medical procedure (n = 11) at the onset. Twenty-four (27%) patients had emotional and physical problems (sudden accident [n = 2], death/funeral of a family member [n = 7], inexperience with exercise [n = 6], quarreling or excessive alcohol consumption [n = 5] and vigorous excitation [n = 4]). Chest symptoms (67%), electrocardiographic changes (ST elevation [90%], Q-wave formation [27%] and T-wave inversion [97%]) and elevated creatine kinase (56%) were found. After treatment of pulmonary edema (22%), cardiogenic shock (15%) and ventricular tachycardia/fibrillation (9%), 85 patients had class I New York Heart Association function on discharge. The LV ejection fraction improved from 41 +/- 11% to 64 +/- 10%. Transient intraventricular pressure gradient and provocative vasospasm were documented in 13/72 (18%) and 10/48 (21%) of the patients, respectively. During follow-up for 13 +/- 14 months, two patients showed recurrence, and one died suddenly. CONCLUSIONS: A novel cardiomyopathy with transient apical ballooning was reported. Emotional or physical stress might play a key role in this cardiomyopathy, but the precise etiologic basis still remains unclear.

Adolescent↗

PubMed2001

Williams syndrome and deficiency in visuospatial recognition.

This study aimed to assess the visuospatial abilities of five children with Williams syndrome (four males aged 9 years 3 months, 7 years 11 months, 8 years 1 month, and 10 years 8 months respectively, and one female aged 6 years 3 months). First, the children's visuospatial abilities were examined by asking them to copy a figure. Second, their cognitive processing abilities were assessed using the Japanese Kaufman Assessment Battery for Children. This test was used because it is an objective one, standardized in Japan, and is a measure of fluid ability including spatial localization. Participants scored significantly low on the spatial memory subtest indicating that there was a deficit in spatial localization. Children's performance in line copying tasks improved when the dots were in colour. Results suggest a deficit in the dorsal stream of visual cognition, with a relatively preserved ventral stream.

Child↗

PubMed2001

A trial study of RhinoSleep for the diagnosis of sleep apnea.

RhinoSleep was developed to diagnose obstructive sleep apnea (OSA). The RhinoSleep consists of a soft catheter, a measuring probe, and a computer. The soft catheter is inserted through the naris into the esophagus. The catheter is connected to the measuring probe, which creates and sends a continuous noise signal into the catheter. When the catheter is compressed during an obstruction, the sound reflections change, making it possible to identify both the level and the duration of the obstruction. Sixteen OSA patients were examined using RhinoSleep and daytime polysomnography simultaneously. With RhinoSleep, we successfully examined 13 cases. This trial study identified problems with RhinoSleep, such as vomiting of the catheter, hardware instability, and the criteria decision for the analysis of OSA.

Acoustics↗

PubMed2001

Comparison of Ricketts analysis and Downs-Northwestern analysis for the evaluation of obstructive sleep apnea cephalograms.

To determine which analysis is suitable to examine the dentofacial skeletal pattern characteristics of the obstructive sleep apnea syndrome (OSAS), we took lateral cephalograms of 44 Japanese OSAS patients and 34 Japanese non-OSAS controls. By Ricketts analysis, we found significant differences between OSAS patients and non-OSAS controls on facial axis, lower facial height and total facial height, which showed that Japanese OSAS patients have dolico facial patterns. However, by Downs-Northwestern analysis, we did not find any significant difference between OSAS patients and non-OSAS controls using the same cephalograms as the Ricketts analysis.

Adult↗

PubMed2001

Uvulopalatopharyngoplasty for obstructive sleep-related breathing disorders: one-year follow up.

The effectiveness of uvulopalatopharyngoplasty was evaluated in 28 patients (25 men and three women; mean age 47.6 years) with obstructive sleep apnea by comparing preoperative daytime polysomnography with those carried out 6 months and 1 year postoperatively. The mean apnea plus hypopnea index (AHI) in the supine position decreased from 51.0/h to 23.0/h 6 months postoperatively and 57.1% of patients showed a 50% or more reduction of AHI. By changing the sleep position from supine to lateral, 71.4% of the 28 patients indicated a 50% or more reduction in AHI before surgery, which increased to 92.3% of 26 patients 6 months postoperatively. The positive results of uvulopalatopharyngoplasty were maintained at least until 1 year after surgery.

Body Mass Index↗

PubMed2001

Dialysis-related amyloidosis of the heart in long-term hemodialysis patients.

BACKGROUND: Dialysis-related amyloidosis (DRA) predominantly occurs in the osteoarticular structures, but it also systemically appears in the extra-articular tissues as well. However, the pathological characteristics of DRA in the hearts of hemodialysis (HD) patients have rarely been reported. METHODS: We studied the pathological characteristics of DRA in the hearts of 18 HD patients, including its relationship to calcification. Furthermore, we studied the immunohistochemical localization of advanced glycation end products (AGEs) using monoclonal anti-imidazolone and anti-Nepsilon-(carboxymethyl)lysine (CML) antibodies. RESULTS: beta2-microglobulin (beta2m) amyloid deposits were detected in the hearts of seven patients who had undergone HD for more than 10 years. beta2m amyloid deposits in the left atrium were localized in the endocardium, the myocardium, and the walls of small blood vessels, whereas in the left ventricle, they were localized only in the walls of small blood vessels. The extent and prevalence of DRA in the heart were severe in the patients on HD for more than 15 years. Most calcification areas near mitral valve were dotted with beta2m amyloid deposits, while diffuse fine calcification was localized within the beta2m amyloid tissues in some cases. Imidazolone and CML were localized not only in massive beta2m amyloid deposits, but also in cardiac myocytes. CONCLUSION: DRAs were localized extensively in the hearts of long-term HD patients. A strong affinity was observed between beta2m amyloid deposits and calcification.

Adult↗

PubMed2001

Localization of imidazolone in the peritoneum of capd patients: a factor for a loss of ultrafiltration.

The presence of dicarbonyl compounds, potent precursors of advanced glycation end products (AGEs), has been recognized in unused peritoneal dialysis (PD) fluids. Accumulation of AGEs has been implicated in the alteration of peritoneal membrane properties during continuous ambulatory peritoneal dialysis (CAPD) therapy. To determine whether imidazolone, an AGE specifically derived from 3-deoxyglucosone (3-DG), contributes to a decrease in ultrafiltration (UF) capacity of the peritoneal membrane in CAPD patients, we immunohistochemically evaluated the localization of imidazolone in peritoneal tissues from CAPD patients. Mesothelial thickening in the peritoneum was found in six of seven CAPD patients. Imidazolone distinctly accumulated in peritoneal tissues of CAPD patients, whereas it was hardly detected in those of patients with nonrenal disease. CAPD patients with a low UF capacity showed more extensive peritoneal deposition of imidazolone and more pronounced mesothelial thickening than those with a normal UF capacity. A CAPD patient with sclerosing peritonitis showed the most abundant localization of imidazolone among all CAPD patients. Gas chromatography/mass spectrometry showed that unused PD fluids contained high 3-DG concentrations (mean, 34.6 +/- 14.1 [SD] microgram/mL). In conclusion, the accumulation of imidazolone was noted in peritoneal tissues of CAPD patients, which preceded a decrease in UF capacity. Imidazolone modification may alter the quality of peritoneal membranes, presumably leading to a loss of UF and finally the development of sclerosing peritonitis.

Epithelium↗

PubMed2001

A successfully treated case of disseminated tuberculosis-associated hemophagocytic syndrome and multiple organ dysfunction syndrome.

We report the case of a patient who presented with disseminated tuberculosis-associated hemophagocytic syndrome (HPS). A 40-year-old man was admitted because of fatigue, fever, and renal dysfunction. Chest radiograph and computed tomography scan showed diffuse reticulonodular shadow, and Mycobacterium tuberculosis was identified. Peripheral blood counts decreased rapidly, and bone marrow aspiration revealed hemophagocytosis by macrophages. Despite antituberculous and steroid pulse therapy, multiple organ dysfunction syndrome developed. After plasma exchange and continuous hemodiafiltration were started, hypercytokinemia and vital signs improved dramatically. Although disseminated tuberculosis-associated HPS carries a poor prognosis, acute blood purification may be an effective means of treating HPS involving multiple organ dysfunction syndrome.

Adult↗