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Biomedical subjects

T Takatori

Publications and source records attributed to T Takatori.

At least 73 records · Page 4Linked to original sources
PubMed1994

Experience with cloned mitochondrial DNA analysis to forensic practice.

The sequencing method of the D-loop region of cloned mitochondrial DNA (mtDNA) together with multilocus and single locus DNA probe patterns was applied to identification of the dismembered and putrefied remains of a pregnant woman. The multilocus DNA fingerprinting was useful to identify whether or not 4 dismembered remains were from the body of the same person, whereas the single locus DNA analysis was useful to decide that the suspect was the father of the fetus. On the other hand, the sequencing method of the D-loop region of cloned mtDNA after amplification by polymerase chain reaction (PCR) was particularly advantageous to highly degraded and contaminated DNA specimens.

Base Sequence↗
PubMed1994

Personal identification from human remains using morphological characteristics and DNA analysis.

This report describes personal identification of four parts of a dismembered human body on the basis of physical characteristics and DNA analysis. A 69-year-old woman suffering from depression went missing from her home in May 1992. Five days after her disappearance, a female torso was found in a river. In a two-week period thereafter, a left forearm, a female head and neck and a right forearm were found consecutively in the same river. Although the end of the cervical vertebra was anatomically identical to that of the torso, the two forearms did not match. However, DNA analyses with a single-locus DNA probe pYNH24, DO alpha typing and a multi-locus DNA probe "Myo", indicated that these four parts came from the same person. The missing woman had undergone lobectomy of the right pulmonary upper lobe, and had suffered from slight scoliosis of the thoracic vertebrae and a second lumbar vertebral compression fracture. These characteristics were also observed in the torso. In order to obtain more conclusive evidence, DNA fingerprinting using DNA extracted from the torso, the missing woman's brother and her daughter was performed using the DNA probes described above. The data obtained indicated that the remains were those of the missing woman.

Aged↗
PubMed1994

[Anesthetic management of a patient with abdominal aortic aneurysm (AAA) with giant bulla].

We report a case of abdominal aortic aneurysm with giant bulla in a 58-year-old man who had an elective abdominal aortic reconstruction surgery. Preoperative chest x-ray showed a giant bulla in the right lung and small bullae in the left. General anesthesia was induced with midazolam 0.5 mg, fentanyl 0.2 mg and succinylcholine chloride 80 mg. After tracheal intubation, anesthesia was maintained under spontaneous breathing with halothane 0.5-1% in a mixture of air and oxygen (FIO2 0.4-1.0) supplemented with continuous epidural mepivacaine from the catheter inserted the day before surgery. Since satisfactory analgesia and muscle relaxation were achieved by epidural mepivacaine, no analgesics and muscle relaxants were administered during the operation. Postoperatively, no complications occurred and the patient was extubated and transferred to the intensive care unit. We emphasize that combined epidural and light general anesthesia with spontaneous respiration might be ideal for the safe anesthetic management of a patient with a giant bulla.

Anesthesia, Epidural↗
PubMed1993

Immunohistochemical localization and dynamics of paraquat in the stomach and esophagus of rats.

The dynamics of paraquat in the stomach and esophagus of rats were demonstrated using immunohistochemical techniques. The Rats were killed 3h, 12h, 24h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In the stomach, paraquat was localized in the epithelial cells between 24 h and 10 days after injection, whereas in the esophagus, paraquat was localized in epithelial cells and the lamina propria mucosa between 12h and 10 days after administration. Although these findings were similar to those observed in the intestine of rats, no clear changes in the distribution of paraquat with time were observed, suggesting that the stomach and esophagus are important reservoirs for the redistribution of paraquat.

Animals↗
PubMed1993

Transport characteristics of paraquat across rat intestinal brush-border membrane.

The mechanism of absorption of paraquat, which is a type of quaternary ammonium compound (QAC), was studied using rat intestinal loops and brush-border membrane vesicles. Approximately 47% and 37% of radioactively labeled paraquat injected into jejunal and ileal loops disappeared, respectively, after 60 min. Since only a small amount of radioactivity was detected in the mucosal fraction, most of the paraquat that disappeared from the intestinal lumen was considered to have been carried away by the bloodstream, indicating that paraquat absorption was greater than expected. In spite of its low lipid solubility, the uptake of paraquat by brush-border membrane vesicles reflected smooth penetration into the intravesicular space rather than binding to the membrane. According to the increase in extravesicular paraquat concentration, paraquat uptake in the early stage was saturable. Moreover, early paraquat uptake was significantly inhibited by structurally-related QACs such as tetramethylammonium and choline, but not by an endogenous dicationic amine (putrescine). On the other hand, inside-negative membrane potential had no significant effect on the time course of paraquat uptake. From these results, it is suggested that paraquat is absorbed through a specialized mechanism associated with the carrier-mediated transport system for choline on the brush-border membrane.

Animals↗
PubMed1993

Novel detection of plankton from lung tissue by enzymatic digestion method.

Studies are reported on the enzymatic digestion method for detection of plankton from lung tissue by using proteinase K with sodium dodecyl sulphate. This method is simple, safe and effective for detection of not only phytoplankton including diatoms but zooplankton which are destroyed by the acid digestion method. The present method is, therefore, much more advantageous for diagnosis of drowning than the disorganization method using strong acids.

Animals↗
PubMed1993

Purification and characterization of NF-R2 that regulates the expression of the human multidrug resistance (MDR1) gene.

NF-R2 is a DNA-binding protein that interacts with the MDR1 gene proximal promoter sequence. We previously reported that NF-R2 binds within the promoter's -126 and -102 regions, which contain the ATTCAGTCA motif. In the present study, we have purified NF-R2 from the nuclear extract of K562/ADM cells, a multidrug-resistant cell line derived from human myelogenous leukemia K562 cells, using sequential chromatography on Sephacryl S-300, DEAE-Sepharose, heparin-Sepharose and a DNA affinity column consisting of a repetitive synthetic ATTCAGTCA motif coupled to Sepharose. NF-R2 runs as a single protein of 75 kDa on SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). CAT (chloramphenicol acetyltransferase) expression assay and gel mobility shift competition assay with mutated promoters revealed that the ATTCAGTCA motif is a positive regulatory element of MDR1 gene and that the motif is important for NF-R2 binding. These results suggest that NF-R2 may be involved in the positive regulation of the MDR1 gene transcription.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

Epidural anesthesia in a patient with myasthenia gravis.

We present a patient with myasthenia gravis who was safely managed by epidural anesthesia during and after thymectomy. An epidural catheter was inserted via the C7-T1 intervertebral space and 2% lidocaine was used during the surgery. The level of analgesia as determined by pinprick extending from C5 to T6. Epidural morphine or morphine and bupivacaine were used for postoperative pain relief. We evaluated ventilatory responses to CO2 and hypoxia after epidural anesthesia with lidocaine or morphine, and during continuous epidural infusion of the mixture of morphine and bupivacaine. Ventilatory responses to CO2 and hypoxia were both depressed following epidural injection of morphine. However, depression of ventilatory responses was not demonstrated following continuous epidural infusion of a mixture of morphine and bupivacaine. This case report suggests that epidural anesthesia is useful as a primary anesthetic and for postoperative pain control in patients with myasthenia gravis.

Adolescent↗
PubMed1993

Production of monoclonal antibodies against diquat and its enzyme-linked immunosorbent assay.

Monoclonal antibodies(MoAbs) very specific to diquat (DQ) were produced. An immunogen was synthesized by binding DQ to bovine serum albumin via a diazo-coupled derivative. BALB/c mice were immunized i.p. monthly with 0.25mg of the immunogen for five months. Their spleen cells were fused with P3U1 myeloma cells and hybridoma clones secreting MoAbs were obtained. Two MoAbs were selected and subtyped to be IgM and IgG3. The MoAbs recognized DQ but did not bind to paraquat and other analogues at all. A datum obtained from a clinical sample demonstrates that an enzyme-linked immunosorbent assay system using one of the MoAbs is useful in the practice of toxicological analysis.

Adult↗
PubMed1993

[Relationship between postmortem change and biological reaction].

In the adipocere which is one of postmortem changes, some specific fatty acids possessing higher melting points together with soap play an important role in the formation of adipocere. These fatty acids were clarified to be mainly 10-hydroxystearic and 10-hydroxypalmitic acids. Moreover, slight amounts of 10-oxostearic and 10-oxopalmitic acids, which have higher melting points than those of hydroxy fatty acids, exist in the adipocere as well. The substantial adipocere is formed and stabilized by these specific fatty acids together with the soap. The hydroxy fatty acid (OHFA) and oxo fatty acid (OXOFA) are biosynthesized by some enzymes from bacteria. Various aerobic and anaerobic bacteria are involved in the formation of adipocere. For example, microbial conversion of various unsaturated fatty acids to 10-OHFA by Micrococcus luteus was investigated. As a result, 10-OHFA was synthesized only from fatty acids possessing cis-9-unsaturation. It was also clarified that 10-OHFAs were converted to the corresponding 10-OXOFAs but the 10-OXO compounds were inactive as substrates. Furthermore, the enzyme preparations from Flavobacterium meningosepticum solubilized by sonication catalyzed not only hydration of oleic acid to produce 10-hydroxystearic acid but also dehydrogenation of this product in the presence of deuterium. On the other hand, we found out that there was 10-hydroxy-12-octadecenoic acid (10-OHLA) from linoleic acid in some kinds of adipocere. 10-OHFA existing in adipocere has been thought not to exist in a living body. However, recently 10-epoxy-12-octadecenoic acid (leukotoxin, LTx) which is one of lipid peroxides was found not only in rice plants but in polymorphonuclear leukocytes. It was also clarified that these polymorphonuclear leukocytes produced the same 10-OHLA as the compound found in adipocere. Since LTx was found from leukocytes related to inflammatory response, it has been interested in involvement of not only the basic mechanism of biological defense but also the mechanism of shock as a vasoactive substance. A postmortem change itself is little associated with a phenomenon on a living body. However, 10-OHLA found in adipocere existed also in polymorphonuclear leukocytes, suggesting that this compound metabolized from LTx is closely related to a biological reaction.

Adipose Tissue↗
PubMed1993

Production and characterization of antibodies reactive with leukotoxin.

A sensitive radioimmunoassay was developed for the determination of leukotoxin (9: 10-epoxy-12-octadecenoic acid), which was reported to exist in human burned skin and neutrophils, and was regarded as a toxic and/or defensive substance in living beings. The leukotoxin was conjugated with bovine serum albumin by means of the mixed anhydride technique as immunogen and rabbits were immunized over 4 months. According to a titration test of antiserum, forty-fold diluted antiserum was found to bind approximately 50% of about 4,000 dpm of methylated leukotoxin labeled with [14C] carbon. The detection limit of leukotoxin was at least as low as 5 ng in this radioimmunoassay by use of a polyetylene glycol precipitation method. This antiserum had a strong specificity to leukotoxin and no cross-reactivity with the other analogs tested.

Animals↗
PubMed1993

Immunohistochemical localization of paraquat in skin and eye of rat.

Immunohistochemical techniques were used to observe the localization of paraquat in the skin and eyes of rats. Paraquat poisoned rats were killed 3 h, 12 h, 24 h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In skin, paraquat was localized in the ducts of sweat glands and sebaceous glands between 3 and 10 days after paraquat injection. In eyes, weak positive findings were observed in nerve fibers of retina between 3 and 10 days after the injection. In cornea, paraquat was localized in epithelial cells at the first 3 h and between 3 and 10 days after paraquat administration. Since skin occupies a vast area of the body in animals, as an organ, it seems to be an important storage pool for the redistribution of paraquat.

Animals↗
PubMed1993

[A case report of acute death caused by hyperextension injury of neck].

We report an autopsy case of acute death from an upper cervical spinal cord injury caused by hyperextension of the neck. A 59-year-old drunken man who had been suffering from cervical spondylosis was slapped in the face, fell flat on his face, and remained as such for 4 hours. The victim was carried to a hospital, he had already been dead on arrival. Although he received an intensive care, he remained unconscious for 12 hours until a cardiac arrest. The findings of an autopsy were as follows: Externally, excoriation on the forehead and the left eyebrow and slight subcutaneous hemorrhage in the dorsum of the nose were observed. The intervertebral disk and the anterior longitudinal ligament between the 5th and 6th cervical vertebrae were severed, and a lot of bleeding in the region of the injuries was observed. The 6th cervical spinous process was fractured in the direction to a major axis. A part of the posterior root filaments was torned and the bleeding points could be seen on the front of the 6th cervical spinal cord. In the cross section of the 6th cervical spinal cord, the typical hemorrhagic necrosis could be recognized surrounding the central canal, whereas the similar finding was observed at the second cervical spinal cord. On the histopathological examinations, in C2, C5-C6 regions marked ischemic changes and hemorrhagic necrosis could be observed. From these post-mortem results, we diagnosed that the victim died from an upper spinal cord damage due to a stretching consequence of the hyperextentional injury.

Autopsy↗
PubMed1992

Purification and characterization of NF-R1 that regulates the expression of the human multidrug resistance (MDR1) gene.

We have purified a protein, NF-R1, that specifically binds to two unrelated motifs--the ATTCAGTCA motif and the GC-box motif--on the MDR1 proximal promoter. Purified NF-R1 has been confirmed by southwestern blotting to be a 110-kDa protein. Methylation interference analysis revealed that the nucleotides were in close contact with purified NF-R1 on the ATTCAGTCA and GC-box motifs. The nucleotides were required for the binding of NF-R1, as seen by competition gel mobility shift assay using point mutated oligonucleotides. In a CAT expression assay using the corresponding point-mutated MDR1 promoter fused to a CAT gene, binding inhibition of NF-R1 to the promoter resulted in 2- to 3-fold increases of CAT activity, as compared to the intact promoter in Adriamycin-resistant K562 cells. Thus NF-R1 has a relation to the negative regulation of the MDR1 gene transcription.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1992

Monoclonal antibodies against haptens.

Four kinds of monoclonal antibodies (moAbs) specific to paraquat, diquat, methamphetamine (MA) and melatonin (MT) were produced. 1-Methyl,1'-hexanoic acid-4,4'-bi-pyridinium, 4-amino-D,L-phenylalanine-diazo-coupled diquat, p-amino-methamphetamine as haptens were synthesized and coupled to bovine serum albumin (BSA) directly or to BSA via glutaraldehyde, and an antigen of MT was prepared by binding MT to BSA with the Mannich reaction. These immunogens of BSA conjugates were immunized i.p. to BALB/C mice. Usable moAbs were established 4 to 6 months after the first immunization. Amounts of paraquat, diquat, MA and MT causing a 50% of inhibition by enzyme-linked immunosorbent assay or radioimmunoassay with one of the most specific moAbs from each hapten were 1.1 ng, 0.67 nmol, 10.0 ng and 1.4 ng, respectively.

Animals↗
PubMed1992

Immunohistochemical classification of astrocytes in infants by glial fibrillary acidic protein staining and application to forensic practice.

This study was designed to assess whether development of the astrocytes in central nervous system (CNS) is delayed in victims of the sudden infant death syndrome (SIDS), and to try the classification of astrocytes by a morphological method. The glial fibrillary acidic protein (GFAP) is the major component of astrocytic fiber and is characteristic of astrocytes in the human CNS. An immunohistochemical study identificating this protein was carried out on infant brains to evaluate astrocytes. Morphologically 39 brains of infants aging under 12 months old, that including 10 asphyxia, 13 respiratory infections and 16 SIDS cases, were stained for GFAP by the peroxidase-anti-peroxidase (PAP) method. According to their staining pattern astrocytes were classified into 4 cell types: Type I cells were seen during the non-proliferating period, Type II cells during the low-proliferating period, Type III cells during the moderate-proliferating period and Type IV cells during the high-proliferating period. On the basis of this classification of astrocytes, it was observed that the first and most reactive pattern of physiological proliferation was in infant brains four months old after birth in the asphyxia cases. The staining grade of astrocytes was significantly less in white matter in the SIDS victims compared with age-matched of the respiratory infections and asphyxia. Therefore, we suggest that development of brain in the SIDS cases is delayed to controls and that the SIDS is associated with a developmental CNS disorder. Among 3 group cases the retarded staining pattern of the astrocytes in SIDS is interesting and might give a helpful approach to diagnosis of the cause of death for SIDS.

Astrocytes↗
PubMed1992

[Trace analysis for drugs and poisons in human tissues].

Despite continuous developments of analytical techniques in terms of sensitivity and accuracy, uncountable increase in number of chemical substances are brought into the field of forensic sciences to be analyzed. Based on the idea that progress in analytical technique to cope with the change of situation is always required, a research team including 10 members was organized to set up the most advanced methods at present to analyze the important drugs and poisons in biological materials for forensic purposes. Stimulant drugs such as methamphetamine and amphetamine were studied on the improvement of extraction procedure prior to mass spectrometric analysis. A conventional solvent extraction method was replaced by an extraction technique using Extrelut column. The technical procedure was simplified and the accuracy of measurement was improved. The changes in CO-Hb concentration in the whole blood in storage was examined with regard to the lapse of time and temperature, where a differential spectrophotometry was used. Useful information could be obtained from practical aspects. Analytical conditions of gas chromatography were revised on volatiles including alcohols, especially as to column conditions. The use of capillary column was recommended for sensitivity and peak separation. The optimum conditions for detecting barbiturates in the blood were examined. The combination of Sep-pak C18 cartridge with a capillary column for gas chromatography using nitrogen phosphorus detection was found preferable. Mass spectrometry of various kinds of local anesthetics was studied. Quantitative analysis of the drugs was examined on gas chromatography with a surface ionization detector. Three types of insecticides including organophosphorus, chlorinated and fluorine compounds were analyzed by gas chromatography/mass spectrometry in order to establish a sensitive and selective method. The detection limits, calibration and reproducibility were examined. Herbicide, paraquat, was examined on the sensitivity, recovery, required time and costs in connection with methods of pretreatment and analytical procedure. A secondary spectrophotometry was found useful practically. Antimony in biological tissues was analyzed, using a flameless atomic absorption spectrometer with carbon tube atomizer. The time for analysis was reduced, and sensitivity was improved. Immunoassay method was examined from general aspects on drugs and hormones. Using antibodies specific to haptens, the dynamics of such antigens as drugs and hormones in the body tissues were observed. Interfering substances at the time of toxicological analysis were checked in order to obtain reliable information. Exact identification was found possible by using gas chromatography/mass spectrometry. As described above, the research was made from the practical aspects of forensic toxicology, and meaningful results could be obtained from each study.

Animals↗