Biomedical subjects
Publications and source records attributed to K Koyama.
A new triterpenoid saponin, named dumortierinoside A, was isolated from Isolatocereus dumortieri. The structure was determined as dumortierigenin 3-O-alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucuronopyranoside (1) on the basis of NMR and mass spectroscopy.
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It is known that human chromosome 2 originated from the fusion of two ancestral primate chromosomes. This has been confirmed by chromosome banding and fluorescence in-situ hybridization (FISH) with human chromosome-2-specific DNA libraries. In this study, the order of 38 cosmid clones derived from the human chromosome region 2q12-q14 was exactly determined by high-resolution FISH in human chromosome 2 and its homologous chromosomes in chimpanzees (Pan trogrodydes, 2n=48) and cynomolgus monkeys (Macacafascicularis, 2n = 42). This region includes the telomere-to-telomere fusion point of two ancestral ape-type chromosomes. As a result of comparative mapping, human chromosome region 2q12-q14 was found to correspond to the short arms of chimpanzee chromosomes 12 and 13 and cynomolgus monkey chromosomes 9 and 15. It is noted that no difference was detected in the relative order of the cosmid clones between human and chimpanzee chromosomes. This suggests that two ancestral ape-type chromosomes fused tandemly at telomeres to form human chromosome 2, and the genomic organization of this region is thought to be considerably conserved. In the cynomolgus monkey, however, the order of clones in each homologue was inverted. In addition to cosmid mapping, two chromosome-2-specific yeast artificial chromosome (YAC) clones containing the fusion point were identified by FISH.
AIMS/BACKGROUND: Hepatic artery interruption (HAI) causes severe ischemic liver damage, especially following hepatopancreatobiliary surgery. In order to inhibit a decrease in oxygen delivery after HAI, continuous infusion of PGE1 via the superior mesenteric artery (SMA) was administered in pigs and changes in hepatic blood flow and oxygen delivery were investigated. Furthermore, its effectiveness in the prevention of liver injury was evaluated by histology and serum enzyme levels. METHODS: Animals were subjected to HAI without PGE1 infusion (control group n=6) and to continuous infusion of PGE1 (0.02 microg/kg/min) into the SMA (PGE1 group n=6). RESULTS AND CONCLUSION: PGE1 infusion via the SMA not only increased the portal blood flow but also elevated the oxygen content of the portal blood. The reduction in oxygen delivery to the liver was 50% in the control group, and only 13% in the PGE1 group. Serum aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) levels 24 h after HAI in the control group were 3415+/-1283 IU/L and 9839+/-2959 respectively while in the PGE1 group they were 939+/-426 IU/L and 5510+/-1545 IU/L respectively. Histological examination showed massive necrosis in the control group at 72 h but only focal liver cell necrosis in the PGE1 group. Based on this finding and the fact that this treatment can be performed easily and safely, continuous infusion of PGE1 via the SMA may be a useful intervention to prevent severe liver damage after hepatic artery interruption.
The involvement of mucosal mast cells (MMC) in protection against infection with the murine nematode parasite Trichuris muris was studied in genetically mast cell-deficient WBB6F1-W/Wv mice and their normal littermates WBB6F1-+/+ mice. Expulsion of T. muris worms occurred in infected +/+ mice, whereas no worm expulsion was observed in infected W/Wv mice where the infection persisted until at least day 46 postinfection. No MMC responses were induced in either infected W/Wv or +/+ mice. Specific IgG1and IgG2a antibodies to T. muris excretory/secretory antigens were observed in infected W/Wv and +/+ mice, and antibody production showed similar kinetics. Interleukin 4 production by concanavalin A (Con A)-stimulated mesenteric lymph node cells (MLNC) was induced preferentially in infected +/+ mice. T. muris infection increased the levels of IFN-gamma produced by Con A-stimulated MLNC of infected W/Wv and +/+ mice, with the levels of IFN-gamma in infected W/Wv mice being higher than those in infected +/+ mice. Taken together, these results indicate that W/Wv and +/+ mice are susceptible and resistant to T. muris infection, respectively, and that MMC responses are not required for protective immunity.
The cabbage butterfly Pieris rapae contains a strong apoptosis-inducing substance, pierisin, against human cancer cell lines, which is thought to act via ADP-ribosylation. Here we report the purification and cloning of an apoptosis-inducing substance, designated as pierisin-2, from another cabbage butterfly, Pieris brassicae. Pierisin-2 was purified from pupae by sequential chromatography and its cytotoxic and apoptosis-inducing activities to various cancer cells were similar to those of pierisin, designated as pierisin-1, from P. rapae. cDNA cloning of pierisin-2 was performed on the basis of the partial amino-acid sequence. The nucleotide sequence indicated that the cDNA encodes an 850-amino-acid protein with a calculated molecular mass of 97 986. The deduced amino-acid sequence of pierisin-2 was 91% identical with that of pierisin-1. In vitro expressed protein in the reticulocyte lysate exhibited apoptosis-inducing activities against human gastric carcinoma TMK-1 and cervical carcinoma HeLa cells, similar to the purified native pierisin-2 from the pupae. Pierisin-2 shows regional sequence similarities with certain ADP-ribosylating toxins such as the A-subunit of cholera toxin. The results from site-directed mutagenesis at Glu165, a conserved residue among ADP-ribosylating enzymes necessary for NAD binding, and from experiments with ADP-ribosylating enzyme inhibitors suggested that pierisin-2 could be considered as an ADP-ribosylating toxin like pierisin-1.
BACKGROUND: The herbicide BASTA (AgrEvo, Germany), containing glufosinate ammonium (20%) and an anionic surfactant, polyoxyethylene alkylether sulfate (33%), is widely used. In acute oral BASTA poisoning, patients develop a variety of clinical signs, including disturbed consciousness, convulsions, and apnea. These effects are suspected to be due to the effects of glufosinate on the central nervous system. CASE REPORT: A 60-year-old man ingested 500 mL of BASTA herbicide in a suicide attempt. He developed not only unconsciousness, respiratory distress, and convulsions but also an increase in urine output (7885 mL/d), elevated serum sodium (167 mEq/L), elevated plasma osmolality (332 mOsm/kg), and a decrease in both urine osmolality (200 mOsm/kg) and urine specific gravity (1.003), which suggested the development of diabetes insipidus. The plasma level of antidiuretic hormone remained within the normal range (1.3 pg/mL), despite high plasma osmolality. The administration of desmopressin was successful in normalizing urine volume, specific gravity, and osmolality. Serum sodium corrected gradually within 48 hours. The possible mechanisms causing the diabetes insipidus are discussed.
To circumvent autoimmune oophoritis after immunization with zona pellucida (ZP) glycoproteins, synthetic peptides encompassing B cell epitope(s) and devoid of oophoritogenic T cell epitopes as immunogens have been proposed. In this study, bonnet monkey (Macaca radiata) ZP glycoprotein-B (bmZPB) was expressed as polyhistidine fusion protein in Escherichia coli. Rabbit polyclonal antibodies against recombinant bmZPB (r-bmZPB) significantly inhibited human sperm-oocyte binding. To map B cell epitopes on ZPB, a panel of 7 murine monoclonal antibodies (mAbs) was generated against r-bmZPB. All 7 mAbs, when tested in an indirect immunofluorescence assay, reacted with bonnet monkey ZP, and only 6 recognized human zonae. Monoclonal antibodies MA-809, -811, -813, and -825 showed significant inhibition in the binding of human spermatozoa to human ZP in a hemizona assay. Epitope-mapping studies using multipin peptide synthesis strategy revealed that these 4 mAbs recognized a common epitope corresponding to amino acids (aa) 136-147 (DAPDTDWCDSIP). Competitive binding studies revealed that the synthetic peptide corresponding to the identified epitope (aa 136-147) inhibited the binding of MA-809, -811, -813, and -825 to r-bmZPB in an ELISA and to bonnet monkey ZP in an indirect immunofluorescence assay. The epitopic domain corresponding to aa 136-147 of bmZPB was completely conserved in human ZPB. These studies will further help in designing ZP-based synthetic peptide immunogens incorporating relevant B cell epitope for fertility regulation in humans.
PROBLEM: The zona pellucida is a good target antigen for contraceptive vaccines due to its strong immunogenicity and high tissue specificity. However, this contraceptive effect is inevitably associated with ovarian failure. Therefore, it is necessary to define an epitope of the zona antigen to which the antibody produced inhibits fertilization without any undesirable side effects. METHOD OF STUDY: The DNA fragment coding for the NH2-terminal region of porcine zona pellucida proteins (ZPA) (1-198 amino acids) and human ZPA (1-206 amino acids) was prepared to produce recombinant porcine ZPA (r-ZPA), r-pZPA1-198 and r-hZPA1-206. Using Freund's complete adjuvant. antisera against these proteins were raised in rabbits. RESULTS: The resultant antisera to r-pZPA1-198 and r-hZPA1-206 were cross-reacted with each other on enzyme-linked immunosorbent assay and immunofluorescent staining. The antiserum to r-pZPA1-198 inhibited in vitro fertilization in pigs, but not human sperm binding to the zona pellucida, while the antiserum to r-hZPA1-206 inhibited the human sperm-binding assay. CONCLUSIONS: Antiserum to r-ZPA inhibited fertilization in the animal species possessing a homologous amino-acid sequence as an immunogen. The recombinant protein, r-hZPA1-206 seems to be a feasible candidate for the development of contraceptive vaccines for humans.
Necdin is a 325-amino-acid residue protein encoded by a cDNA clone isolated from neurally differentiated embryonal carcinoma cells. Ectopic expression of necdin induces growth arrest of proliferative cells. Necdin binds to major transcription factors E2F1 and p53, suggesting that necdin exerts its functions through the interactions with these cell-cycle-regulating factors. However, information about precise localization of endogenous necdin protein is currently lacking. A rabbit polyclonal antibody was raised against a bacterially expressed recombinant protein of necdin (amino acids 83-325). Immunoblot analysis revealed that necdin protein was expressed almost exclusively in the brain of adult mice. A relative molecular mass of endogenous necdin was estimated at approximately 43,000. In developing mouse brain, necdin was most abundant during fetal and neonatal periods. Necdin was highly enriched in the cytoplasm of hypothalamic neurons in fetal and adult mice. The subcellular fractionation analysis revealed that necdin was concentrated in the cytosol fraction of brain cells. These results suggest that endogenous necdin protein is localized predominantly in the cytoplasm of differentiated neurons and moves into the nucleus under specific conditions.
AIM: In the treatment of severe liver damage, it is of greater advantage to administer prostaglandin E(1) (PGE(1)) directly to the liver compared with systemic intravenous infusion, because of its high inactivation rate in the lungs. In comparison with intraportal infusion, hepatic arterial infusion is more advantageous because of its easier and safer accessibility. This study was designed to prove the superiority of hepatic arterial infusion to intravenous infusion. METHODS: Changes in hepatic hemodynamics and oxygen delivery accompanying PGE(1) infusion using both methods were investigated in pigs. In addition, continuous hepatic arterial infusion was applied in 3 cases of postoperative acute liver failure, for patients in whom other conventional treatments like plasma exchange failed to improve the functioning of the liver. RESULTS: Hepatic arterial flow increased significantly accompanying hepatic arterial infusion of PGE(1) at a rate of 0.1 microg/kg/min compared with intravenous infusion at the same rate in pigs. Such an increase resulted in elevation of total hepatic blood flow and oxygen delivery to the liver. Correspondingly, bile flow significantly increased accompanying hepatic arterial infusion of PGE(1). Continuous hepatic arterial infusion was applied in 3 cases of postoperative acute liver failure. The infusion was continued for 7-9 days at a rate of 0.01 microg/kg/min without any complications through heparin-coated catheters inserted via the femoral artery. Significant increase in bile flow was observed in 2 cases in whom bile was collected, serum total bilirubin began to decrease in all these 3 cases, and the patients recovered from acute liver failure. CONCLUSION: Hepatic arterial infusion of PGE(1) is very useful and effective in the treatment of acute liver failure.
We examined the association of alexithymic characteristics and the expression of unfavorable feelings such as anger and hostility in a sample of 489 Japanese college students. Analysis suggested that alexithymic college students are prone to indicate not only emotional instability but also cynical hostility and anger. On the contrary, alexithymic college students indicated significantly higher scores on Anger-in and Anger Control, which may be related to Japanese sociocultural aspects. In particular, Anger Control was stronger in the men who were alexithymic, suggesting that they may unconsciously struggle for the suppression or control of unfavorable feelings such as anger and hostility to stabilize their inner emotions.
A case of Klinefelter's syndrome with schizophrenia-like symptoms is reported. He was given a diagnosis of schizophrenia at the age of 39. After being treated with medication for many years, he stopped taking them at the age of seventy-two and involuntary movements appeared in his limbs and the trunk. Upon admission to our hospital, he was experiencing delusion and psychosocial excitement. A physical examination showed him to be a thin man of 175.5 cm height, suffering from a mild degree of gynecomastia, testicular atrophy. Serum LH and FSH were both high 10.9 and 47.8 mU/ml respectively. Serum testosterone concentration was 0.2 ng/ml, much lower than the normal range (2.7-10.7 ng/ml). On the Wechsler adult intelligence scale (Revision), his total IQ was 103 (performance IQ 100, verbal IQ105). Karyotype analysis revealed an XXY pattern. Although slight auditory hallucinations remained, the delusional symptoms as well as the involuntary movements diminished after the administration of psychotrophics. Personality changes such as apathy and abulia was subsided. The psychological symptoms were very similar to these of cases in other reports of Klinefelter's syndrome associated with schizophrenia-like symptoms. Some reports about the relationships between sex hormones and schizophrenia including other psychotic disorders suggest that the X-chromosome plays an important part in the mechanism of psychosocial symptoms and in the prognosis in Klinefelter's syndrome.
Standardized treatment plan for gastric cancer was established in our department by which surgeons and nurses understood the treatment schedules of each gastric cancer patient as the common knowledge, and the cooperation of surgeons and nurses could be improved. Furthermore, the modality decreased the length of hospital stay from 35 +/- 15 days to 24 +/- 8 days, which indicated that the number of patients per one bed for one year increased from 10 to 15, and the efficiency of the treatment of gastric cancer patients 50% by our system.
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The discrimination of poisoning from other conditions is essential. When multiple patients with similar clinical findings are seen, deliberate poisoning should be considered along with the possibility of resulting from accidental food poisoning, infection, diseases resulting from extreme circumstances, and mass hysteria. The diagnosis of causal poisoning chemicals based on clinical findings is essential. Breath odors, findings of vomitus, skin color, body temperature, autonomic nervous system findings, and seizures are important physical findings. On the other hand, laboratory findings such as ECG abnormalities, metabolic acidosis, increased serum hepatic enzyme levels, and increased serum blood urea nitrogen and creatinine levels are also useful in obtaining the correct diagnosis. X-ray films are useful in demonstrating several types of radiopaque drugs in the stomach. Rapid tests are valuable in diagnosing poisoning caused by such chemicals as paraquat and cyanides. Therapeutic diagnoses obtained by administering competitive blockers of specific receptors are also valuable when benzodiazepine or opiate poisoning is suspected. The final diagnosis of the causal chemical should be based on both the clinical findings and analytical results.
We have previously reported that the cabbage butterfly, Pieris rapae, contains a 98-kDa protein, named pierisin, that induces apoptosis in a variety of human cancer cell lines. In the present study, sequencing and cloning of a cDNA encoding pierisin was accomplished. PCR-direct sequencing showed that the gene encodes an 850-amino acid protein with a calculated molecular weight of 98,081. An intact clone at the amino acid level encompassing the entire coding region was obtained by recombination of two independent clones, and the molecular mass of its in vitro expressed protein was about 100 kDa on SDS/PAGE, the same as that of purified native pierisin. The expressed protein induced apoptosis in human gastric carcinoma TMK-1 and cervical carcinoma HeLa cells, like the native protein, indicating functional activity. The deduced amino acid sequence of pierisin showed 32% homology with a 100-kDa mosquitocidal toxin from Bacillus sphaericus SSII-1. In addition, pierisin showed regional sequence similarities with ADP-ribosylating toxins, such as the A subunit of cholera toxin. A glutamic acid residue at the putative NAD-binding site, conserved in all ADP-ribosylating toxins, was also found in pierisin. Substitution of another amino acid for glutamic acid 165 resulted in a great decrease in cytotoxicity and induction of apoptosis. Moreover, inhibitors of ADP-ribosylating enzymes reduced pierisin-induced apoptosis. These results suggest that the apoptosis-inducing protein pierisin might possess ADP-ribosylation activity that leads to apoptosis of the cells.
Pierisin, a protein purified from pupae of the cabbage butterfly, Pieris rapae, exhibits cytotoxic effects against the human gastric cancer TMK-1 cell line, inducing apoptosis. The present study was performed to determine whether pierisin might exert a similar influence on nine other human cancer cell lines and human umbilical vein endothelial cells (HUVECs). Pierisin showed cytotoxic effects in all the human cells tested, with IC50 values ranging from 0.043 ng/ml to 150 ng/ml. Among the target cells, the cervical carcinoma cell line, HeLa, was the most sensitive to pierisin, showing a 1000-fold less IC50 value than that of HUVECs. While pierisin clearly induced apoptotic cell death in most cancer cell lines and HUVECs, the pathway appeared to be probably different from that involving anti-Fas, TNF-alpha and p53. Pierisin may thus be a promising new candidate for cancer therapy.