Prevention of autoimmune insulitis in nonobese diabetic mice by expression of major histocompatibility complex class I Ld molecules

Nonobese diabetic (NOD) mice spontaneously develop a T-cell-mediated autoimmune disease that is similar in many respects to insulin-dependent diabetes mellitus in humans. NOD mice were shown to express major histocompatibility complex class I Kd and Db antigens. To examine the possible involvement of major histocompatibility complex class I molecules in the development of autoimmune insulitis, we attempted to express a different type of class I molecule in NOD mice by crossing C57BL/6 mice transgenic for the class I Ld gene with NOD mice. The backcross progeny expressed the Ld antigen on the peripheral blood lymphocytes at a level comparable with that of the BALB/c mice. The cell surface expression of endogenous class I and class II antigens on the peripheral blood lymphocytes was not affected. Analysis of these mice revealed that the expression of the class I Ld antigen significantly reduced the incidence of insulitis at 20 weeks of age. In situ hybridization of a biotinylated probe on mouse chromosomes showed that the Ld transgene was located in the E area of chromosome 6 with which no genetic linkage to insulin-dependent diabetes mellitus was demonstrated. These results suggest that the NOD-type class I molecules are involved in the development of insulitis in NOD mice.

[Asphyxial death by laryngopharyngeal tumor--two autopsy cases]

Case 1. A 44-year-old male died about 3 h after paracenteses of both palatine tonsils. A 6.5 x 2.5 x 2.0 cm tumor, caused by bleeding and edema, was revealed at medico-legal autopsy. This tumor extended from the right palatine tonsil to the right edge of epiglottis. The cause of death was determined to be acute asphyxia due to the obstruction of the airway by the tumor. Case 2. A 51-year-old female was thought to have been killed by manual strangulation. At medico-legal autopsy, three malignant tumors, each of which was not as large as the tip of the little finger, were found in the lower pharynx. There were no findings of acute asphyxia death. The cause of death was determined to be delayed asphyxia caused by the malignant tumors.

[Serum alpha 1-antichymotrypsin in senile dementia]

To evaluate the clinical significance of serum alpha 1-Antichymotrypsin (ACT) as an early diagnostic marker of senile dementia of Alzheimer type (SDAT), we measured 333 healthy and not demented elderly subjects, 27 cases SDAT and 25 cases of vascular dementia (VD). For the measurement, a new high-sensitivity method, double antibody radioimmunoassay method was developed. In healthy elderly subjects, the mean value of serum ACT was 0.229 mg/ml. A tendency towards increase of ACT with aging was noted but was not significant. The serum level of ACT in the SDAT patients was significantly higher (0.309 mg/ml) compared with the healthy elderly subjects and the VD patients (0.226 mg/ml) (p < 0.01). We concluded that in the patients with SDAT, there was an overproduction of ACT and the serum value of ACT was markedly elevated. The measurement of serum ACT is very useful (sensitivity = 88.9%, specificity = 68.7%; cut-off value = 0.250 mg/ml) for the early differential diagnosis of senile dementia.

Myristoylation-dependent membrane targeting and release of the HTLV-I Gag precursor, Pr53gag, in yeast

The unprocessed HTLV-I Gag precursor, Pr53gag, was synthesized in yeast, Saccharomyces cerevisiae. The synthesized Pr53gag was myristoylated, associated with the cellular membrane, and released into the culture medium. The released Pr53gag was pelleted by centrifugation at 100,000 x g for 2 h. Conversion of Gly2 to Ala allowed synthesis of a non-myristoylated soluble Pr53gag which was not released into the culture medium. These results suggest that the release of the HTLV-I Gag precursors Pr53gag, occurs in yeast in a myristoylation-dependent manner.

Discrepancy between estimated and actual time elapsed after death of a severed head

A severed head which had been wrapped in seven plastic bags and set in concrete in an airtight insulated plastic box was found approximately 22 months after the occurrence of death. Ammonium magnesium phosphate had formed and on the basis of this and other observed postmortem changes, time elapsed after death was estimated to be from 2 weeks to 6 months. The absence of oxygen is thought to have contributed significantly to the great discrepancy between estimated and actual time elapsed after death.

Inhibitory anti-tumor effects of interleukin-4 on Philadelphia chromosome-positive acute lymphocytic leukemia and other hematopoietic malignancies

IL-4 has been shown to possess a broader spectrum of biological activities. Recently, anti-tumor activities of IL-4 on malignant tumors including hematopoietic tumors has been revealed in vitro or in vivo. We investigated the effect of recombinant human (rhIL-4) on the in vitro growth of human leukemia cells and demonstrated the inhibitory anti-tumor activity of rhIL-4 on Ph1-positive ALL cells in association with the decreased activity of cellular tyrosine kinase. This finding suggests that the clinical evaluation of rhIL-4 may offer promising therapeutic possibility for patients with Ph1-positive ALL. In this paper, we presented the IL-4-dependent inhibition of Ph1-positive ALL cells and reviewed implications for mechanism of IL-4-dependent inhibition and anti-tumor activities of IL-4.

Combination of conventional and endotoxin-specific limulus tests for measurement of polysaccharides in sera of rabbits with experimental systemic candidiasis

Factor G, the coagulation enzyme from limulus amebocytes, is activated by (1-->3)-beta-D-glucan but not by endotoxin. The endotoxin-specific limulus test, which is devoid of factor G, reacts only with endotoxin. However, the conventional limulus test which includes factors G and C, reacts with not only endotoxin but also with (1-->3)-beta-D-glucan. In this study, the culture supernatant of Candida albicans in RPMI medium activated the conventional limulus test, but not the endotoxin-specific limulus test. All five rabbits inoculated intravenously with Candida albicans (1.0 x 10(7) CFU/rabbit) showed increased levels of reactivity with the conventional limulus test, whereas no elevation in the levels of the endotoxin-specific limulus test was observed in the sera of any infected rabbits. Only one serum sample from rabbit No. 5 on day 8 showed a positive Cand-tectest. The difference in the titers of the two limulus tests was suggestive of a diagnosis of Candida infection.

Proteolytic processing sites producing the mature form of human cathepsin D

1. The proteolytic processing sites of human lysosomal aspartic protease cathepsin D at which the intermediate single-chain form was converted into the mature two-chain form were determined. 2. The two chains were isolated by reversed-phase HPLC in order to investigate the cleavage sites of the enzyme. 3. Protein sequencing of the heavy chain, which was presumed to be derived from the C-terminal side in the single-chain enzyme, gave an N-terminal Leu 105. In addition, it revealed that there were also minor sequences, which commenced with Gly 106 and Gly 107. 4. A small C-terminal peptide was isolated from the light chain, which had been digested with two kinds of exogenous proteases. Sequence determination of this peptide, which was characterized as a nonapeptide by mass spectrometry, suggested that the C-terminus of the light chain was Ser 98. 5. These results indicate that a Ser 98-Ala 99 bond and an Ala 104-Leu 105 bond are cleaved to release 6 amino acid residues between the two chains.

Effect of herbimycin A, an antagonist of tyrosine kinase, on bcr/abl oncoprotein-associated cell proliferations: abrogative effect on the transformation of murine hematopoietic cells by transfection of a retroviral vector expressing oncoprotein P210bcr/abl and preferential inhibition on Ph1-positive leukemia cell growth

Herbimycin A, a benzoquinoid ansamycin antibiotic, was demonstrated to decrease intracellular phosphorylation by protein tyrosine kinase (PTK). In Philadelphia chromosome (Ph1)-positive leukemias such as chronic myelogenous leukemia (CML) and Ph1-positive acute lymphoblastic leukemia (ALL), both of which express bcr-abl fused gene products (P210bcr-abl or P190bcr-abl protein kinase) with augmented tyrosine kinase activities, herbimycin A markedly inhibited the in vitro growth of the Ph1-positive ALL cells and the leukemic cells derived from CML blast crisis. However, the same dose of herbimycin A did not inhibit in vitro growth of a broad spectrum of Ph1-negative human leukemia cells, and several other protein kinase antagonists also displayed no preferential inhibition. Furthermore, we demonstrated that herbimycin A has an antagonizing effect on the growth of transformed cells by a transfection of retroviral amphotrophic vector expressing P210bcr/abl into a murine interleukin (IL)-3-dependent myeloid FDC-P2 cell line. This inhibition was abrogated by the addition of sulfhydryl compounds, similar to the reaction previously described for Rous sarcoma virus transformation. The inhibitory effect of herbimycin A on the growth of Ph1-positive cells was associated with decreased bcr/abl tyrosine kinase activity, but no decrease of bcr-abl mRNA and protein, suggesting that the inactivation of bcr-abl tyrosine kinase activity by herbimycin A may be induced by its binding to the bcr-abl protein portion that is rich with sulfhydryl groups. The present study indicates that herbimycin A is a beneficial agent for the investigation of the role of the bcr-abl gene in Ph1-positive leukemias and further suggests that the development of agents inhibiting the bcr-abl gene product may offer a new therapeutic potential for Ph1-positive leukemias.

[Analysis of thinner components using the Curie-point pyrolyzer-gas chromatographic method in the tissues of a victim fatally poisoned]

A 43-year-old male was found dead in the trunk of his car which was filled with thinner vapor. Thinner components in the tissues were analyzed using a gas chromatograph equipped with Curie-point pyrolyzer (Py-GC), and a gas chromatograph-mass spectrometer. The Py-GC method was able to analyze with very small materials. It was simple and quick but not as sensitive as the head-space gas chromatographic method. Toluene, ethylbenzene and xylenes were detected in the tissues, and their presence was confirmed by gas chromatography-mass spectrometry. The concentrations of toluene, ethylbenzene and xylenes in blood and the brain were 56.8, 6.8 and 4.5 micrograms/ml; and 203, 43.5 and 33.9 micrograms/g, respectively. The cause of death was thus judged as be thinner poisoning.

Superoxide dismutase activity, lipid peroxide production and corpus luteum steroidogenesis during natural luteolysis and regression induced by oestradiol deprivation of the ovary in pseudopregnant rabbits

The relationship of oxygen free radicals to corpus luteum function in rabbits was explored during various stages of pseudopregnancy, including natural and induced luteal regression. Induced luteolysis was achieved during mid-pseudopregnancy by removal of an oestradiol capsule placed at the onset of pseudopregnancy, which suppressed ovarian oestradiol production. Activity of manganese superoxide dismutase (Mn SOD) was significantly and positively correlated with ovarian progesterone production (P < 0.01) throughout pseudopregnancy and during natural regression. Oestradiol deprivation for 12, 24 or 72 h resulted in declines in Mn SOD activity and progesterone secretion, although Mn SOD rose and corpus luteum steroidogenesis was restored to normal when the capsule was replaced for 48 h before assessment, having been removed for 24 h. Lipid peroxide and progesterone concentrations were not correlated, although a significant rise in lipid peroxides in the luteal tissue was detected after deprivation of oestradiol for 72 h. Changes in progesterone production and Mn SOD activity were not associated with alterations in concentration of prostaglandin F metabolite. These data suggest that Mn SOD may be involved in regulating function of the corpus luteum during pseudopregnancy in rabbits and that oxygen free radicals may play a role in regression of corpus luteum in this species.

Physicochemical characteristics and antitumor activities of a highly branched fungal (1----3)-beta-D-glucan, OL-2, isolated from Omphalia lapidescens

Physicochemical properties and antitumor activities of a fungal (1----3)-beta-D-glucan, OL-2, isolated from Leiwan (Omphalia lapidescens) were examined. OL-2 showed sharp signals on carbon-13 nuclear magnetic resonance spectrum in dimethylsulfoxide-d6 as a solvent, and these signals were significantly reduced by the addition of distilled water to the concentration of 20%. This phenomenon is consistent with the general property of the gel forming (1----3)-beta-D-glucan. Binding of OL-2 to Congo red induced a significant change of lambda max to a longer wavelength, and the concentration to induce gel to sol transition was about 0.7 N; in contrast, the concentration was about 0.2 N in the cases of SPG and curdlan. These observations suggested that the gel structure would be significantly stabilized in the case of OL-2. OL-2 showed no or low antitumor activity against the solid form of Sarcoma 180 by intraperitoneal and intralesional administrations; however, it was effective on the ascites form of Sarcoma 180. Of interest, OL-2 also showed significant antitumor activity against the ascites form of MH-134 when administered with 5-fluorouracil. These results indicated that OL-2 showed characteristic features regarding its physicochemical properties and antitumor activity.

[Antimutagenic activities of hexane extracts of the fruit extract and the kernels of Prunus mume Sieb. et Zucc]

Antimutagenic activities of hexane extracts obtained from the fruit extract (UE) and the Kernels (KE) of P. mume were examined. These extracts showed inhibitory activities to known mutagens, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide, benzo[alpha]pyrene and aflatoxin B1 in the Ames assay using Salmonella typhimurium TA100 and TA98 strains. The UE and KE fractions were then separated by silicic acid column chromatography with a stepwise elution method using ether-hexane. The location of the active substances in the fractions was also determined by thin-layer chromatography. Consequently, it was found that the effective substances for the desmutagenicity were fatty acids, and identified by gas liquid chromatography, mainly as oleic acid, linoleic acid and linolenic acid in UE, and mainly as oleic acid and linoleic acid in KE, respectively.

[Limulus test (factor G) and polysaccharides from fungus]

Picogram quantifies per ml of endotoxin showed a positive limulus test. The concentration more than ten pg/ml of curdlan ((1-3)-beta-D-glucan) was also positive to a conventional limulus test, which contains a factor G. One nanogram per ml of CM-curdlan was positive, but higher concentration of 10 pg/ml of CM-curdlan decreased its optical density of the conventional limulus test. More than one hundred ng/ml of mannan from Saccharomyces cerevisiae did not react with factor G. However, a culture supernatant of Saccharomyces cerevisiae activated factor G. This result suggested that beta-glucan activated factor G. In addition, culture supernatant of Aspergillus fumigatus, Rhodotorula rubra, Candida parapsilosis, Candida tropicalis, Candida krusei also activated factor G, but Cryptococcus neoformans did not activate it.

Effects of nitric oxide-related compounds and carperitide on hemodynamics and hematocrit in anesthetized rats

Sodium nitroprusside, nitroglycerin and carperitide (alpha-human ANP) all reduced mean blood pressure, but only carperitide increased the hematocrit in rats with bilateral renal artery- and ureter-ligation. NG-Monomethyl-L-arginine, a selective inhibitor of nitric oxide synthesis, elevated the mean blood pressure but did not change the hematocrit significantly. These findings suggest that ANP has a physiological role in regulating circulatory blood volume distinct from that of NO, although both increase intracellular cyclic GMP in the vasculature.

[A case of suicide by an intravenous injection of pancuronium]

A 25-year-old male anesthesiologist was found dead in his room with an intravenous drip line connected with his leg. There were several empty ampules of pancuronium, midazolam and buprenorphine around him. Pancuronium and midazolam in the blood and urine samples collected at postmortem examination were detected by spectrofluorometry and ECD-gas chromatography, respectively. The concentrations of pancuronium and midazolam were 0.3 micrograms/g and 0.12 micrograms/g in the blood, respectively; 0.9 micrograms/g and 0.05 micrograms/g in the urine, respectively. The cause of death was determined to be asphyxia due to respiratory muscle paralysis caused by pancuronium.

[A 14-year-old with pulmonary hamartomatous lymphangiomyomatosis associated with bilateral pneumothoraces]

A 14-year-old girl was admitted because of cough, chest pain and hemosputum. Chest roentgenogram on admission showed a pneumothorax and a cavitary lesion with niveau formation in the right lung and cystic lesions in the bilateral lung fields. After bed rest and intravenous administration of antibiotics for two weeks, the right lung inflated well and the niveau formation disappeared, and the patient was discharged. One week later, she was readmitted with sudden-onset severe dyspnea, caused by bilateral pneumothoraces. Emergency tube thoracostomy and wedge resection of the bullous lesion was performed. Macroscopically, multiple small cystic changes were seen on the surface of the right lung. Histological examination revealed nodular proliferations of smooth muscle cells in the interstitium and vessel walls in the lung, which contained slit-like lymphatic channels. The diagnosis of pulmonary lymphangiomyomatosis was made. In this case, we could not measure receptors for estrogen and progesterone. Recently, hormonal therapy and oophorectomy have been reported as being useful. Tamoxifen (Norvadex) was therefore initiated, and the patient has remained well with slight dyspnea on exertion. There has been no recurrence of pneumothorax. Lymphangiomyomatosis is a rare disease of unknown etiology which occurs exclusively in women, mostly in those of reproductive age. We report a 14-year-old female patient with lymphangiomyomatosis associated with repeated pneumothorax, who had been under treatment for epilepsy. We believe this case to be of importance because of the long discussed relation between pulmonary lymphangiomyomatosis and tuberous sclerosis.

Interpretation of COHb concentrations in the left and right heart blood of cadavers

Carbon monoxide hemoglobin (COHb) concentrations in left and right heart blood samples from cadavers both exposed and not exposed to fire or CO gas were analyzed by the gas chromatographic method. The COHb concentration ratio between samples of left and right heart blood (L/R ratio) does not appear to be useful for establishing whether death has occurred before or after exposure to fire with the exception of cases where no soot can be detected in the airways by the naked eye and the COHb concentration in the blood sample is within the level considered normal for tobacco smokers.

[A fatal case caused by organophosphorus insecticide intoxication and confirmed by the metabolite found in the blood]

An 83-year-old woman and two other members of her family were poisoned after eating lettuce prepared with Ethimethon Granule 6 instead of salt by mistake. Ethimethon Granule 6 is a mixture of organophosphorus pesticides, disulfoton and diazinon. All three were admitted to a hospital, and she died 22 h after ingestion and the others recovered. Disulfoton and diazinon in the remaining lettuce were detected and confirmed by gas chromatography-mass spectrometry. The pesticides, however, were not detected in the blood sample collected from the victim at autopsy. A metabolite of disulfoton, phosphorothiolate sulfone, was detected by FPD-gas chromatography, and confirmed by gas chromatography-mass spectrometry.

[A clinical study of tuberculous pleurisy]

Forty-eight cases of tuberculous pleurisy were examined and the following results were obtained. (1) Most of the patients were male, and there was no significant age and underlying diseases. (2) Fever and chest pain were observed mainly in younger patients, and sputum and dyspnea in older patients. (3) All of the cases examined had exudative pleural effusion, and increased ADA activity was frequently observed. (4) Mycobacterium tuberculosis was detected in the sputum of 65%, and also in the pleural effusion of 28% of the patients. The pathological diagnosis of tuberculosis was made by pleural biopsy in 83% of the patients, suggesting that pleural biopsy is very useful in the diagnosis of tuberculosis pleurisy. (5) The prognosis of the patients with tuberculosis pleurisy was good. Steroid therapy was generally ineffective.

Stress-induced gastric mucosal lesion and platelet aggregation in rats

The effect of cold-restraint stress on platelet function in vitro was studied in the rat model. Platelet function was assessed by platelet aggregation in response to adenosine diphosphate (ADP) and thrombin. ADP-induced platelet aggregation was reduced in platelet-rich plasma after 2 h of cold-restraint stress. Thrombin-induced platelet aggregation was reduced with time during cold-restraint stress with a parallel increase in the lesion index. Although pretreatment of animals with atropine prevented the development of gastric mucosal lesions, platelet dysfunction was not reversed by this treatment. These results suggest that cold-restraint stress may impair platelet function, probably due to platelet activation in vivo, and that the abnormalities in platelet function may be associated with the development of gastric mucosal lesions.

DNA sequence analysis of the dnaK gene of Escherichia coli B and of two dnaK genes carrying the temperature-sensitive mutations dnaK7(Ts) and dnaK756(Ts)

The DNA sequence of the dnaK gene of Escherichia coli was analyzed. The nucleotide sequence of the wild-type dnaK gene of E. coli B differed from that of E. coli K-12 in 15 bp, none of which altered the amino acid sequence. Two temperature-sensitive dnaK mutations were examined by cloning and sequence analyses. Results showed that one dnaK mutation, dnaK7(Ts), was a one-base substitution of T for C at nucleotide position 448 in the open reading frame yielding an amber nonsense codon. The other mutation, dnaK756(Ts), consisted of base substitutions (A for G) at three nucleotide positions, 95, 1364, and 1403, in the open reading frame resulting in an aspartic acid codon in place of a glycine codon.

Gene expressions and activities of protein phosphatases PP1 and PP2A in rat liver regeneration after partial hepatectomy

We have examined the levels of gene expressions and activities of protein phosphatases, PP1 and PP2A, in rat regenerating livers. PP1 alpha mRNA started to increase from 6 h after partial hepatectomy (PH) and showed two peaks at 12 and 48 h. PP2A mRNA level showed two peaks at 6 and 10-12 h. Protein phosphatase activities were determined both in non-nuclear fraction and in nuclei. While spontaneous PP1 activity in non-nuclear fraction was nearly constant, potential PP1 activity revealed by Co(2+)-trypsin treatment showed a small peak between 7 and 12 h. In nuclei, both spontaneous and potential PP1 activity began to increase from 4-7 h after PH, reached a maximum (about 2.5-fold over control levels) at 12 h, the time which corresponds to the G1 to S transition in the cell cycle, and then declined back to control levels by 7 days. PP2A activity in non-nuclear fraction was nearly constant in both spontaneous and potential forms. PP2A activity in both forms in nuclei was very low throughout. These results suggest the possibility that PP1 in nuclei plays some role in the G1 to S transition in the cell cycle of hepatocyte proliferation.