PubMed Health⌕ Search

Biomedical subjects

S Takeichi

Publications and source records attributed to S Takeichi.

At least 19 recordsLinked to original sources
PubMed2000

Determination of chronic methamphetamine abuse by hair analysis.

A 30-year-old male truck driver, known to be asthmatic, was found dead at the roadside lying near his car. A nebulizer bottle of Berotec (fenoterol hydrobromide) was found near his hand. The anatomic cause of death was suspected to be asthma. Toxicological screening of urine using Triage demonstrated the presence of methamphetamine. The blood concentration of methamphetamine was 0.4 microg/ml, and fenoterol was not detected. Hair analysis clearly indicated chronic methamphetamine abuse and medium dependency during the 2 months before death. We conclude that death might have been induced by the interaction of fenoterol and methamphetamine.

Adult↗
PubMed2000

A case of fatal methemoglobinemia of unknown origin but presumably due to ingestion of nitrate.

A case of fatal methemoglobinemia (MetHb-emia) which was presumably due to ingestion of nitrate is presented. An unidentified man was taken to a local emergency hospital suffering from deep cyanosis and 7 h later he was found dead in the hospital bed. The post-mortem examination of the blood revealed a methemoglobin (MetHb) concentration of 78% and the concentrations of nitrate and nitrite were 1.50 and 0.76 microg/mL, respectively. Capillary gas chromatography coupled to mass spectrometry (GC-MS) and capillary gas chromatography with a nitrogen-phosphorus detector (NPD) were used to detect nitrates and nitrites in the blood.

Aged↗
PubMed1999

Association of plasma triglyceride-rich lipoprotein remnants with coronary atherosclerosis in cases of sudden cardiac death.

Among the risk factors for coronary atherosclerosis, elevated LDL-C level is best known. The action of lipoprotein lipase on triglyceride-rich lipoproteins produces remnant lipoprotein particles enriched in cholesterol and apolipoprotein E (apo E). Apo E serves as the ligand for uptake of remnant lipoproteins via the LDL-receptor or the remnant receptor. In this study, postmortem plasma total cholesterol, triglycerides (TG), VLDL-C, HDL-C, lipoprotein (a) [Lp(a)] and remnant-like lipoprotein particles (RLP)-cholesterol, RLP-TG, apolipoproteins B, C III and E were measured, together with LDL-C to assess their potential contribution to the severity of coronary and aortic atherosclerosis of the 197 cases of sudden death (132 cardiac death and 65 non-cardiac death). In all cases, the severity of coronary atherosclerosis was determined at postmortem pathological examination. RLP-cholesterol (RLP-C) and LDL-C concentrations were significantly higher in cases with advanced coronary atherosclerosis compared with those without coronary atherosclerosis; respective median values were 13.5 vs 8.4 mg/dl (P < 0.001) and 140 vs 115 mg/dl (P < 0.05). RLP-C levels were more strongly correlated with the severity score of coronary atherosclerosis than LDL-C.

Adult↗
PubMed1999

Effects of muscle relaxants on EEG, ABR and EMG in rabbits.

The effects of baclofen and pancuronium bromide on evoked electromyogram (EMG), cortical electroencephalogram (EEG) and auditory brainstem responses (ABR) were studied in pentobarbital anesthetized normal rabbits. Evoked EMG was measured in the gastrocnemius muscle by electrical stimulation of the sciatic nerve. Intravenous injection of baclofen decreased EEG and arterial blood pressure and light reflex, however, it had no significant influence on EMG or ABR at doses of 10 and 20 mg/kg/h. Pancuronium bromide immediately inhibited respiration, decreased EEG and EMG, however, it had no significant influence on arterial blood pressure, ABR, or light reflex, at doses of 0.4 and 1.0 mg/kg/h in anesthetized rabbits. ABR waves were observed until just before cardiac arrest with both of the muscle relaxants. It is suggested that ABR are not influenced by central or peripheral muscle relaxants, or by pentobarbital.

Acoustic Stimulation↗
PubMed1999

[Searching for a new risk factor of sudden cardiac death].

Sudden death of cardiovascular origin has been recognized as a major cause of sudden natural death. Advanced coronary atherosclerosis often co-existent, despite this, little or no coronary atherosclerosis was seen in approximately half of the sudden coronary death cases. Some components in the blood seem to induce not only the coronary atherosclerosis but also coronary spasm and/or thrombogenesis under certain conditions, which does not necessarily relate to the severity of atherosclerosis. Postmortem plasma lipids and lipoprotein levels, especially triglyceride-rich lipoprotein remnants (abbreviated as remnants) were measured as remnant-like particles-cholesterol (RLP-C) and triglyceride (RLP-TG) in two groups of Japanese subjects who died suddenly and unexpectedly due to coronary or non-coronary causes. Our study on the postmortem plasma analysis of lipids and lipoproteins indicated that RLP-C was most strongly correlated with the severity of the coronary atherosclerosis and to be the best predictor among various parameters. Furthermore, RLP-TG appeared to be highly associated with the risk of sudden coronary event or death, especially in cases without advanced coronary atherosclerosis, which might be associated with clinical events as coronary spasm or thrombosis. Biological activities of RLP from postmortem plasmas of sudden coronary death cases showed strong effects on platelet aggregation and impaired vasorelaxation in vitro. RLP determined as RLP-TG might affect on the process of spasm or on the formation of thrombus in the coronary artery at the time of sudden coronary death, independent of the severity of coronary atherosclerosis. These data might be clinically important to predict or to prevent sudden coronary death. The studies were conducted as followed: 1) Separation, purification and quantitative analysis of remnants from postmortem plasma. 2) Isolation and characterization of remnants from postmortem plasma. 2-1) Assessment of the methods of TG measurement. 2-2) Characterization of remnants by HPLC methods. 2-3) Characterization of remnants by electrophoresis. 2-4) Electron microscopical observation of remnants. 3) Lipid and lipoprotein analysis of sudden coronary death and control cases. 3-1) Lipid and lipoprotein levels of sudden coronary death and control cases. 3-2) Plasma remnant levels in the postprandial state. 3-3) Severity of coronary atherosclerosis and plasma lipid and lipoprotein levels, especially remnant levels. 3-4) Sudden coronary death cases without advanced coronary atherosclerosis and their plasma lipid, lipoprotein levels, especially remnant levels. 4) Biological activities of the remnants. 4-1) Endothelium-dependent vasodilator function in the coronary artery. 4-2) Aggregation of human blood platelets by remnants. 5) Fatty acids analysis of remnants from sudden coronary death cases. 6) Immuno-histochemical examination of various apo-lipoproteins on the coronary artery. 7) Gene analysis of plasma lipid metabolites.

Apolipoproteins↗
PubMed1998

Increased complex formation of Gc globulin with actin in plasma from human cadavers.

Gc globulin binds actin at an equimolar ratio with a high affinity. It has been revealed that complexes of Gc with actin are present in the plasma of human cadavers. In the present study, an immunoassay which we developed using a specific anti-Gc monoclonal antibody was applied to evaluate the complexed Gc in cadaver plasma. The percentage of Gc in the complexed form was found to be 38.3 +/- 19.8% (n = 45), and a significantly higher percentage was observed in the plasma of cadavers from burn death. However, the plot of the complex percentage against the time since death showed a relatively low correlation, with a coefficient (r) of 0.51. This was supposed to be due to different environmental conditions after death. Since the complex formation represents the release of cytoplasmic actin into plasma from collapsed cells, the phenomenon should be noted in forensic postmortem chemistry.

Actins↗
PubMed1998

Epitope analysis of monoclonal antibodies to human Gc globulin (vitamin D-binding protein).

Gc globulin, also called vitamin D-binding protein, is a human 56 kDa plasma protein. Antigenic epitopes of the protein recognized by 12 different monoclonal antibodies (MoAbs), including the previously prepared MoAb E12 of which binding to Gc is inhibited by actin, were analyzed in relation to the functional domains of the protein. To map the epitopes recognized by the respective antibody, the reactivities of the MoAbs were tested by immunoblotting against the recombinant Gc fragments expressed in E. coli cells, and then a competitive ELISA was performed. The results showed that the antibodies were classified into at least six groups. Furthermore, in addition to E12, actin inhibited the reactivity of MoAb 21, of which the epitope was located within residues Asp320 to Glu379, in an ELISA in the presence of the ligand. This result must indicate that this antibody-binding site is near the site that interacts with actin. In contrast, no inhibitory effect by 25-hydroxyvitamin D to any antibodies was observed. Furthermore, all antibodies, including E12 and 21, reacted with membrane-bound Gc of lymphocytes by an immunofluorescence study, suggesting that Gc is unlikely to bind to the plasma membrane in its interaction with actin.

Actins↗
PubMed1998

Sudden natural death in driving: case studies in the western area of Kanagawa.

To assess their incidence and implications, we made a retrospective study of sudden unexpected natural deaths during driving that occurred in the five year-period between 1992 and 1997. During that period, 188 postmortem examinations were performed on driver victims of traffic accidents. Of these, 15 (8%) were found to have died of natural causes such as heart disease or cerebral hemorrhage. Marked findings in this study were that no persons over 70 years of age and more occupational drivers suffered natural death. Although no passengers or pedestrians were injured, as many as eight vehicles collided with another object or vehicle. Sudden natural death, particularly from cerebral hemorrhage, of drivers might be hazardous to other road users.

Accidents, Traffic↗
PubMed1998

Changes in brain barbiturate concentration in brain-dead rabbits.

Pentobarbital concentration was evaluated in the brain tissues of brain-dead rabbits. Pentobarbital was infused into the vein of Japanese white male rabbits at 60 mg/kg/h until an isoelectric EEG of the cortex was reached. Brain death was induced by inflation of a balloon catheter placed in the subdural space. The diagnosis of brain death was confirmed by a flat line ABR wave. A significant increase in heart rate, intracranial pressure, and mean arterial pressure, was observed following brain death induction. These parameters returned to below basal values within 60 mm. Immediately after, and at 6 h and 24 h after brain death, each group of rabbits was sacrificed by phenobarbital overdose, and brains were then removed for determination of pentobarbital concentration in the brain tissue. Blood pentobarbital disappeared about 18 h after brain death was induced. Although the brain pentobarbital concentration slightly decreased over time, a high concentration of pentobarbital remained in the brain 24 h after brain death was induced.

Animals↗
PubMed1997

Structure of the gene encoding human alpha 2-HS glycoprotein (AHSG).

Alpha 2-HS glycoprotein (AHSG) is a human plasma glycoprotein and fetuin is the homologue in the calf. In this report, we present the structure and organization of the AHSG gene. Introns and the 5' and 3'-flanking regions were obtained by polymerase chain reaction (PCR) and the inverted PCR, respectively, from genomic DNA using AHSG cDNA-specific oligonucleotide primers. The sequence of the PCR products shows that the coding region spans approximately 8.2 kb and is composed of seven exons interrupted by six introns. The exon-intron splice junctions agree with the consensus sequence, and the positions interrupted by introns are precisely identical to those of the rat insulin receptor tyrosine kinase inhibitor (fetuin) gene. The 5'-promoter region contains several characteristic sequences such as an A + T-rich sequence of TAAATAA, C/EBP-binding site, and hepatocyte nuclear factor-5 (HNF-5) and serum response factor (SRF) sites.

Animals↗
PubMed1997

The possible role of remnant-like particles as a risk factor for sudden cardiac death.

Postmortem plasma lipid and lipoprotein levels were analyzed in two groups of Japanese subjects who died suddenly and unexpectedly due to cardiac (n = 93) or non-cardiac (n = 26) causes. No individuals in either group had a significant medical or cardiac history. In this study, we measured plasma total cholesterol, triglycerides, VLDL-cholesterol, LDL-cholesterol, HDL-cholesterol, and especially triglyceride-rich lipoprotein remnants. Triglyceride and apo E-rich remnant-like particles (RLP) were studied as a possible risk factor for sudden cardiac death in relation to the progression of coronary atherosclerosis. The receiver-operating characteristic curve (ROC) analysis showed that RLP-TG was the most significant risk factor for sudden cardiac death among the lipids and lipoproteins and RLP-C was the best predictor for coronary atherosclerosis. HDL-C and LDL-C levels were within normal limits in the majority of the cases and did not appear to relate to the sudden cardiac death. Apo E phenotyping was performed for the detection of the genetic background in the lipid metabolism. The frequency of the Apo E3/3 (wild type) phenotype, which closely relates with the remnant metabolism, was significantly reduced in the sudden cardiac death group. Our study on the postmortem plasma lipid analysis suggested that RLP-C and RLP-TG are the best risk predictor for coronary atherosclerosis and sudden cardiac death, respectively.

Adult↗
PubMed1997

Molecular evidence for human alpha 2-HS glycoprotein (AHSG) polymorphism.

Alpha 2-HS glycoprotein (AHSG) is a human plasma glycoprotein that exhibits genetic polymorphism on isoelectric focusing (IEF). To identify the origin of two common alleles, AHSG*1 and *2, we examined nucleotide exchanges in the gene. AHSG cDNA was obtained by RT-PCR from poly(A) RNA of seven liver tissue samples and subcloned into a plasmid vector. After sequencing, we found six single nucleotide differences in comparison with the originally reported sequence. In particular, the nucleotide substitutions of C to T at amino acid position 230 and C to G at position 238 were common among the samples exhibiting phenotype 2-1 or 2. Since these substitutions might give rise to a NlaIII site and a SacI site, respectively, for the potential AHSG*2, we analyzed these substitutions by PCR-RFLP using genomic DNA of 68 individuals. The result was consistent with the IEF analysis of the corresponding serum, indicating that AHSG*1 was characterized by ACG (Thr) at position 230 in exon 6 and ACC (Thr) at position 238 in exon 7, and that AHSG*2 was characterized by ATG (Met) at position 230 and AGC (Ser) at position 238.

Amino Acid Sequence↗
PubMed1997

Bispecific rabbit Fab'-bovine serum albumin conjugate used in hemagglutination immunoassay for beta-microseminoprotein.

A polyclonal bispecific (bifunctional) antibody was prepared to develop a hemagglutination immunoassay for beta-microseminoprotein (beta-MSP), a predominant seminal protein. Three types of F(ab')2 fragments of rabbit IgG, affinity-purified anti-human red blood cell (RBC) F(ab')2 nonaffinity-purified anti-beta-MSP F(ab')2 and nonspecific (nonimmunized) F(ab')2, were mixed to obtain a F(ab')2 mixture containing 10% anti-RBC molecules and 10% anti-beta-MSP molecules. Fab' was obtained from the F(ab')2 mixture, and then reacted with maleimide-activated bovine serum albumin (BSA) at a molar ratio of 10:1. As estimated by the decrease in the maleimide content, approximately 7 Fab' molecules were introduced per one BSA molecule. The bispecific (anti-beta-MSP and anti-RBC) Fab'-BSA conjugate thus prepared was incubated successively with a human RBC suspension and with samples. In the presence of beta-MSP, RBCs become agglutinated, providing a test simple for forensic semen identification.

ABO Blood-Group System↗
PubMed1997

Experimental studies of methemoglobinemia due to percutaneous absorption of sodium nitrite.

OBJECTIVE: Methemoglobin formation caused by a liniment solution containing sodium nitrite (30 g/L and 140 g/L) was studied in rats with normal or abraded skin, by measuring the methemoglobin concentration before and after application of liniment solutions with differing nitrite concentration. METHODS: Each liniment solution (120 microL) was applied. Methemoglobin was measured for 180 minutes using a hemoximeter. Simultaneously, arterial blood pressure and cutaneous blood flow was measured by laser Doppler flowmetry and a pressure transducer. RESULTS: After the application of each liniment solution to normal skin, the methemoglobin concentration was not significantly modified depending on the time after application. Application of liniment solution to abraded skin (140 g/L) resulted in a marked increase in methemoglobin concentration. A remarkable decrease in arterial blood pressure and subcutaneous blood flow were observed after application of liniment solution to abraded skin (140 g/L). CONCLUSIONS: Each of these findings are characteristic of nitrite and they imply the percutaneous absorption of nitrite. Regardless of the nitrite concentration, the methemoglobin concentration was consistently higher in abraded skin than in normal skin.

Administration, Cutaneous↗
PubMed1997

[Long-term follow-up study of children with minimal change nephrotic syndrome].

We conducted a long-term follow-up study of 37 children with biopsy-proved minimal change nephrotic syndrome during a period of over 6 years from onset to adulthood. These patients were classified into 4 groups of 13 infrequent relapsers, 17 frequent relapsers, 3 non-responders and 4 no-relapsers according to the International Study of Kidney Disease in Children (ISKDC). All patients were treated with conventional prednisolone therapy. Two cases of infrequent relapsers, 7 cases of frequent relapsers and 1 case of non responders relapsed in adult life. Two cases of infrequent relapsers and 1 case of frequent relapsers relapsed in adult life after remission for 5 or more years. We concluded that minimal change nephrotic syndromes in childhood should be followed up over a long duration in adult life, evenly in cases with good steroid responsiveness.

Child↗
PubMed1997

Experimental studies on effects of barbiturate on electroencephalogram and auditory brain-stem responses.

The effects of pentobarbital on electroencephalogram (EEG) and auditory brain-stem response (ABR) were evaluated in 13 Japanese white male rabbits, divided into two groups, 7 and 6, respectively. After baseline evoked responses were obtained, pentobarbital was infused intravenously at 60 mg/kg/h in both groups. EEGs and ABR were recorded with 15 min intervals. When the blood concentration of pentobarbital reached therapeutic levels (2.0-5.0 mg/dL), cortical and hippocampal EEGs became isoelectric. Although the appearance of ABR waves was significantly delayed, each wave was clearly observed in spite of isoelectric EEG levels. The rabbits in one group were killed at that time, and their brains were removed to determine the concentration of pentobarbital in the brain tissue. In another group, pentobarbital was additionally infused at the rate of 120 mg/kg/h. Although the waves (II-IV) of the ABR gradually disappeared with increasing dosage, wave I was present until just prior to cardiac arrest. It is considered that the persistency of ABR at high doses of barbiturates is characteristic of patients in deep barbiturate coma. Therefore, at the diagnosis of brain death, there is no necessity to consider the half-life of the barbiturate, even if an excessive amount of barbiturate remains in the brain. In this study, pentobarbital concentration in the brain was nearly equal to the concentration in the blood. However, it is estimated that a large amount of barbiturate is accumulated in the brain of a patient after brain death because the blood flow in the brain is stagnant.

Animals↗