In vitro activity of the hairpin ribozyme derived from the negative strand of arabis mosaic virus satellite RNA

The negative strand of the satellite RNA of tobacco ringspot virus [(-)sTRSV] is a self-cleaving RNA, of which self-cleaving domain is called the hairpin ribozyme. The negative strand of the satellite RNA of arabis mosaic virus [(-)sArMV] has been suggested to have a hairpin ribozyme-like secondary structure, and we have previously shown that this hairpin domain of (-)sArMV has ribozyme activity. Here we report characterization of the cleavage reaction of the (-)sArMV hairpin ribozyme. Mutagenesis analyses in a trans-acting system revealed, surprisingly, that the wild-type ribozyme was less active than almost all the other mutant ribozymes tested. In a cis-acting system (self-cleaving reaction), however, the reaction of the RNA containing the wild-type sequence proceeds highly efficiently. This result suggests that the inefficient cleavage of the wild-type substrate in trans-acting system may be due to low efficiency at the substrate-binding step but not at the chemical cleavage step in the reaction. We also constructed a chimeric ribozyme between the catalytic hairpin domain from (-)sArMV and the substrate-binding site from (-)sTRSV. This chimeric ribozyme had the highest activity among the trans-acting hairpin ribozymes tested.

A case of a pony with Cushing's disease

The pars intermedia of the pituitary gland, and plasma ACTH and cortisol levels in the pony, which was first diagnosed in Japan as indicating equine Cushing's disease, were examined by immunohistochemistry and radioimmunoassay, respectively. The pars intermedia was greatly enlarged and most of its cells were immunoreactive for antisera to both adenocorticotropic hormone (ACTH) and beta-endorphin (beta-End). The plasma ACTH level was elevated when clinical symptoms appeared. The present results reveal that equine Cushing's disease in this pony was induced by the hypersecretion of ACTH and beta-End from the enlarged pars intermedia of the pituitary gland.

Cerebrospinal fluid tau levels in neurodegenerative diseases with distinct tau-related pathology

Cerebrospinal fluid tau (CSF-tau) levels were quantified in 8 patients with frontotemporal dementia (FTD), 6 patients with progressive supranuclear palsy (PSP), 3 patients with corticobasal degeneration (CBD), and 6 patients with dementia with Lewy bodies (DLB). The CSF-tau levels were significantly increased in FTD and DLB, but not in PSP and CBD, compared to that previously reported in normal controls. Notably, the CSF-tau level in DLB was as high as that in Alzheimer's disease (AD). Our study suggests that tau may accumulate in the CSF of patients with certain neurodegenerative diseases other than AD and that measurement of CSF-tau may not distinguish AD from DLB.

Ischaemic heart disease deaths in a Japanese rural area evaluated by clinical records

A community-based survey to examine the actual number of ischaemic heart disease (IHD) deaths was undertaken in the western area of Toyama, a rural area with a population of 209,000. IHD deaths (International Classification of Diseases [ICD], ninth revision, codes 410-414) and heart failure (HF) deaths (ICD code 428) according to the death certificate aged 15 to 74 in 1987 to 1990 were reevaluated from medical records using the criteria of the multinational monitoring of trends and determinants in cardiovascular disease (MONICA). Of 97 subjects with IHD and of 170 subjects with HF according to the death certificate, 85 cases (87.6%) and 143 cases (84.1%) could be examined, respectively. Using the MONICA criteria, of 85 subjects with IHD, 18 (21.2%) were reevaluated as "definite acute myocardial infarction (AMI)" and 30 (35.3%) as "possible AMI". On the other hand, of 143 subjects with HF, 1 (0.7%) were reevaluated as "definite AMI" and 12 (8.4%) as "possible AMI". From these results, the number of deaths as reevaluated IHD was estimated 104.5 in the study period, and it was 7.7% increase at least compared with the number of deaths judged from the death certificate.

[Relationship between learning behavior and genetic factor on immobility shown during forced swimming test]

The relationship between learning and genetic factor on immobility in mice during a forced swimming test (FST) has been studied. The duration of immobility during the FST did not change significantly after the administration of either scopolamine (2.5 mg/kg, ip) or cyclohexamine (150 mg/kg, ip), although both drugs produced impairment in the learning task. This suggests that the increase in immobility observed during the second trial of the FST may not be related to learning which could occur during the first trial. Concerning the strain difference, first, the duration of immobility in C3H mice was shorter than that in ICR, ddY, C57BL and BALB mice. Second, after receiving shock stress in a box, ICR, ddY and C57BL mice, but not C3H mice showed a marked decrease in locomotor activity when placed in the box again without shock. Also during the FST, both C57BL and ddY mice, but not C3H mice showed prolongation of immobility and reduction in swimming after shock stress. The changes in locomotor activity, and immobility and swimming during the FST caused by shock stress in ddY mice recovered to normal levels after treatment with imipramine. From these results, it is suggested that the immobility shown during the FST, which may be independent of learning and dependent on some genetic factor, is a suitable model of depression in animals.

[Thymic carcinoma associated with pulmonary sarcoidosis]

A 54-year-old man who worked as a farmer was admitted to the hospital in August 1989 because of bilateral hilar adenopathy that was detected during a mass screening. Laboratory examination showed a high serum lysozyme level and the PPD skin test was negative. Examination of a specimen obtained by transbronchial lung biopsy revealed non-caseous epithelioid cell granuloma. Sarcoidosis was diagnosed. The patient was not treated, and the bilateral hilar adenopathy had lessened by 1992. The patient was readmitted to our hospital because of right hilar and upper mediastinal enlargement seen on a chest radiograph in April 1994. Computed tomography and magnet resonance imaging disclosed an anterior mediastinal tumor in contact with the right upper lobe, the left inominate vein, and the pericardium. Bronchoscopy showed no abnormality in the right upper-lobe bronchus. Examination of a specimen obtained from the B3b bronchus showed no evidence of malignant cells. Examination of a tumor specimen obtained by transdermal biopsy showed squamous cell carcinoma. After the patient underwent combination chemotherapy, the tumor ws resected, along with the right upper lobe, the left inominate vein, and the pericardium, which were difficult to separate from the tumor. Postoperative pathological examination showed that squamous cell carcinoma was intermingled with normal thymus tissue. We believe that squamous cell carcinoma originated in the thymus. Non-caseous epithelioid cell granulomas were also found in the resected right upper lobe and in a mediastinal lymph node. The patient was discharged after post-operative irradiation of the mediastinum. Thymic carcinoma is rare, and sarcoidosis in a patient with thymic carcinoma is very rare. T lymphocytes are very important in the pathogenesis of sarcoidosis, and the thymus is involved in the growth and differentiation of T lymphocytes. The occurrence of these two diseases in one patient is interesting, but the relationship is not clear.

Purification and characterization of a dipeptidyl carboxypeptidase from Pseudomonas sp. WO24

A dipeptidyl carboxypeptidase (DCP) activity was detected in cell-free extracts of Pseudomonas sp. WO24. After purification and characterization the enzyme was found to be homogeneous by SDS-PAGE, and had a molecular mass of 74,000 Da by SDS-PAGE and 72,000 Da by gel filtration, indicating that it is monomeric. The isoelectric point was 5.2 and optimum pH was 6.5-7.0. It showed a specific activity of 780 mumol/min/mg, which is the highest of the values shown by known enzymes. The enzyme hydrolyzed angiotensin I to angiotensin II and sequentially released Phe-Arg and Ser-Pro from the C-terminus bradykinin. The DCP could not cleave imido-bonds, Gly-Gly bonds, or tripeptides. The enzymatic activity was completely inhibited by 0.001 mM EDTA and 0.1 mM O-phenanthroline, but it was not affected by general serine and cysteine protease inhibitors. Addition of Zn2+ completely restored the original activity of the inactivated DCP treated with EDTA. These results suggest that this enzyme is a zinc metalloprotease. The characteristics of the purified enzyme are slightly different from those of the DCPs from Escherichia coli, Pseudomonas maltophilia, and Corynebacterium equi, and considerably from those of the DCP from Bacillus pumilus.

Primary cardiac angiosarcoma: 53 months' survival after multidisciplinary therapy

An 8-year-old girl underwent surgical excision of a tumor arising from the right atrium immediately after admission. Because histologic and immunohistochemical examination confirmed the diagnosis of angiosarcoma, adjunctive multidisciplinary therapy was administered for the following 2 years. She is leading a normal school life 53 months after the operation. Therapeutic strategy for this highly malignant cardiac tumor is discussed.

Triple primary cancers involving kidney, urinary bladder, and liver in a dye worker

A case of triple primary cancers (renal cell carcinoma of the kidney, transitional cell carcinoma of the bladder, and hepatocellular carcinoma of the liver) was reported at autopsy. A 53-year-old man, who had a history of exposure to benzidine, underwent nephrectomy for a left renal cell carcinoma and 10 years later, transurethral resection of bladder tumor (TUR-Bt) for a transitional cell carcinoma of the bladder. At the age of 65, he was diagnosed as having multiple hepatic tumors. Histological examination of biopsy specimens showed these lesions to be undifferentiated carcinomas. Immunohistological examination of both biopsy and autopsy specimens revealed that multiple hepatic tumors were hepatocellular carcinomas, not metastatic tumors from kidney or urinary bladder: tumor cells of hepatic tumors were positive for alpha-fetoprotein, although renal cell carcinomas and transitional cell carcinomas of urinary bladder were positive for Ber-EP4 and keratin, respectively. These findings suggest not only that immunohistological examination is helpful for the diagnosis of multiple primary cancers but also that benzidine may be hepatocarcinogenic in addition to those cancers that are known to be associated with benzidine exposure, i.e., renal cell carcinomas and transitional cell carcinomas in urinary bladder.

Ten-year follow-up study on the relation between the development of non-insulin-dependent diabetes mellitus and occupation

To investigate the relation between occupation and the development of non-insulin-dependent diabetes mellitus (NIDDM), we undertook a 10-year follow-up survey of male employees of a zipper and aluminum sash factory in Japan. Of 1,218 employees we followed 1,087 subjects. We classified the subjects into five occupations: managers, technical workers, clerical workers, workers in transport, and laborers. NIDDM incidence was 3.1% for 10 years. The age-adjusted incidence of the workers in transport was the highest and that in laborers was the lowest. We used a multiple logistic analysis for adjustment with baseline characteristics such as age, BMI, fasting plasma glucose, and family history of diabetes mellitus. Adjusted relative risk of the workers in transport compared with the laborers was significantly high (3.95). Our work suggests that occupation is related to the development of NIDDM.

Purification and characterization of dipeptidyl aminopeptidase from Aureobacterium sp. WO26

We isolated a bacterial strain with an enzyme which releases dipeptide from Gly-Arg-p-nitroanilide. The bacterium was tentatively identified as Aureobacterium sp. The enzyme, named AuDAP, was purified and characterized. It was homogenous by SDS-PAGE and IEF, and had a molecular mass of 90,000 Da by SDS-PAGE and 88,000 Da by gel filtration, so it may be a monomer. The isoelectric point was 3.8 and the optimum pH was 10.0. The purified enzyme hydrolyzed Gly-Arg-pNA, a model substrate for DAP I, and Arg-Arg-MNA, a model substrate for DAP III. However, this enzyme did not hydrolyze Gly-Phe pNA, also a model substrate for DAP I. These results suggested that this enzyme did not fall under the classification of mammalian DAPs and was similar to DAP BI from Pseudomonas sp. WO24 and dDAP from Dictyostelium discoideum, although several differences were observed between them. The N-terminal amino acid sequence of this enzyme showed no significant homology to any enzyme and protein, except only for DAP BI.

Dipeptidyl aminopeptidase IV from Pseudomonas sp. WO24

Dipeptidyl aminopeptidase IV from Pseudomonas sp. WO24 was purified as two molecular forms of 84 and 82-kDa by SDS-PAGE. Peptide mapping and N-terminal sequence analyses indicated that both proteins might be derived from the same protein, and that the 82-kDa molecule might be a truncated form from the 84-kDa molecule at least at the N-terminus. The DAP IV gene of Pseudomonas sp. WO24 was cloned and expressed in E. coli. The enzyme expressed in E. coli JM109 harboring a hybrid plasmid, pYO-6A, with about a 3-kbp fragment containing the DAP IV gene, was purified with an activity recovery of 24%. The recombinant enzyme also had the same two molecular forms, though the ratio of the two forms (about 1:1) was different from that of the native ones (about 1:4). The native and recombinant enzyme preparations had similar specific activities, suggesting that the 84 and 82-kDa molecules are in an active form and have almost the same specific activity. The molecular mass, the subunit number, the substrate specificity, and the effects of various inhibitors of the native enzyme indicated that this enzyme was a typical DAP IV and had properties similar to those of Flavobacterium meningosepticum rather than others.

Two types of novel dipeptidyl aminopeptidases from Pseudomonas sp. strain WO24

Two kinds of dipeptidyl aminopeptidase I (DAP I [cathepsin C])-like activities which hydrolyze Gly-Phe-p-nitroanilide (Gly-Phe-pNA) were detected in Pseudomonas sp. strain WO24. They were purified and characterized. The isolated enzymes, named DAP BII and DAP BIII, were revealed to be homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing. DAP BII was estimated to have a molecular mass of 150,000 Da by gel filtration and a subunit size of 73,000 Da by SDS-PAGE, indicating it to be a homodimer. The molecular mass of DAP BIII was evaluated to be approximately 60,000 Da by gel filtration and 69,000 Da by SDS-PAGE, indicating that it is monomeric. The isoelectric points of DAP BII and DAP BIII were 6.1 and 5.0, and their optimal pHs were 8.0 and 8.5 to 9.0, respectively. The result of peptide mapping for DAP BII and DAP BIII showed that these enzymes consist of different components. Both enzymes were completely inhibited by diisopropylphosphofluoride but not by general thiol inhibitors, indicating that they are serine proteases. DAP BII and DAP BIII hydrolyzed Gly-Phe-pNA but not Gly-Arg-pNA, both of which are model substrates for mammalian DAP I. Despite these shared activities toward DAP I, DAP BII released dipeptides from Ala-Ala-pNA and Lys-Ala-4-methylcoumarinamide (a substrate for DAP II), whereas DAP BIII did not hydrolyze either of these compounds and was presumed to prefer substrates composed of bulky, hydrophobic amino acids at P1 and P1' positions. In addition, DAP BII showed no endopeptidase activity, whereas DAP BIII possessed the activity on N-terminally blocked peptide derivatives besides exopeptidase activity. Assays performed with bioactive peptides such as angiotensin I and neuromedin N as substrates indicate that DAP BII has a considerably broader substrate specificity than DAP BIII and is able to hydrolyze an X-Pro bond, an imido bond that few peptidases and no known DAPs can cleave. These characteristics, namely, substrate specificities, molecular mass, pI, peptide mapping, pH optimum, and effect of inhibitors, suggested that the two DAPs purified in this work are distinct enzymes and do not belong to any of the previously reported DAP classes.

Baculovirus vectors for expression in insect cells

Recombinant baculoviruses now represent a mature technology in which vector development, particularly for the control of expression level, has reached a plateau. However, other aspects of expression, such as the production of multiple proteins, improved product purification or maximizing protein processing, remain areas for novel vector and host cell development. This year has seen these topics come to the fore in descriptions of new expression systems.

Expression of IL-3 receptor in testis

Interleukin-3 (IL-3) is a potent growth factor for hematopoietic cells. IL-3 transmits its signal through a specific cell surface receptor which consists of a primary binding alpha subunit (IL-3R alpha) and a signaling beta subunit that is shared by the IL-5 and GM-CSF receptors. Here, we describe the expression of the alpha and beta subunit of the IL-3 receptor in mouse testis and testicular cell lines both at nucleic acid and protein levels. Our data indicate that IL-3R alpha is expressed on the cell surface of testicular Leydig cells and a Leydig cell tumor cell line I-10. Expression of the beta subunit mRNA was only faintly detected in testis, but not in I-10 cells. Immunoelectron microscopy has revealed that IL-3R alpha is present on cell membrane and microvilli.

Prosthetic management for edentulous glossectomy patients

The prosthetic treatment of edentulous glossectomy patients is very difficult. The tongue defect results in oral dysfunction and affects the stability of the mandibular denture. The appropriate denture form and occlusion can be established by using the modified functional impression technique. Through the use of x-ray television and an image-processing system in clinical experiments, it was shown that a wide buccolingual table, an occlusal table height matched to that of the tongue body, and close adherence of the tongue and the lingual flange are effective means of preventing food from dropping to the oral floor, keeping the food on the occlusal table, and crushing the food.

Identification of an oncogenic form of the thrombopoietin receptor MPL using retrovirus-mediated gene transfer

Thrombopoietin and its receptor (MPL) are important regulators of megakaryopoiesis. We have identified an activating mutation of MPL using a combination of a retrovirus-mediated gene transfer and polymerase chain reaction-driven random mutagenesis. This point mutation causes a single amino acid substitution from Ser498 to Asn498 in the transmembrane region and abrogates factor-dependency of all interleukin-3-dependent cell lines tested. Murine interleukin-3-dependent Ba/F3 cells expressing the mutated but not the normal form of MPL were tumorigenic when transduced into syngeneic mice. Analysis of intracellular signaling pathways indicated that the mutant MPL protein constitutively activated two distinct signaling pathways, SHC-Raf-MAPK and JAK2-STAT3/STAT5.

Nodular lymphoid hyperplasia of the terminal ileum: report of a case and the findings of an immunological analysis

The immunological and immunohistochemical characteristics of a patient with nodular lymphoid hyperplasia (NLH) of the terminal ileum were investigated pre- and post-operatively. The patient presented with diarrhea, lower abdominal pain, and weight loss, and an abdominal X-ray following barium enema revealed multiple small nodules in the terminal ileum which were subsequently confirmed to be NLH by histological examination. Preoperatively, although the serum immunoglobulin levels were normal, the T-cell responses in the peripheral blood, including the phytohemagglutinin (PHA)-blastogenesis and the T4/T8 ratio, were impaired. However, following an ileocecal resection, the PHA-blastogenesis became augmented and the T4/T8 ratio recovered to within the normal range. The immunohistochemical findings revealed a more marked accumulation of T cells in the interstitium around the hyperplastic follicles than in the interstitium of the normal intestine.

The pulmonary alveolar proteinosis in granulocyte macrophage colony-stimulating factor/interleukins 3/5 beta c receptor-deficient mice is reversed by bone marrow transplantation

Mice mutant for granulocyte macrophage colony-stimulating factor (GM-CSF) or the common receptor component (beta c) for GM-CSF, interleukin (IL)-3, and IL-5 exhibit a lung disorder similar to human pulmonary alveolar proteinosis, a rare disease with congenital, infantile, and adult forms. Bone marrow transplantation and hematopoietic reconstitution of beta c mutant mice with wild-type bone marrow reversed the established disease state in the lungs, defining this disease as hematopoietic in nature. It is likely that the disease involves alveolar macrophages, as donor myeloid cell engraftment into the lungs of mutant recipient mice correlated with reverting both the disease and an abnormal macrophage morphology seen in the lungs of affected animals. Recombination Activating Gene-2 mutant donor bone marrow, which lacks the potential to develop lymphocytes, reversed the pathology in the lungs to the same extent as whole bone marrow. These data establish that certain lung disorders, if of cell-autonomous hematopoietic origin, can be manipulated by bone marrow transplantation.

[A case of genitourinary double cancers detected by health screening]

A 58-year-old male with left renal cell carcinoma and prostatic carcinoma occurring synchronously, is reported. He visited our hospital, because of the high level of serum prostate-specific antigen (PSA) pointed out in a health screening by his company. Prostatic cancer was detected in both lobes of the prostate by needle biopsy specimens and histopathology represented moderately > poorly differentiated adenocarcinoma. Magnetic resonance imaging (MRI) and computed tomography (CT) revealed no cancer invasion beyond the prostate and no lymph node metastasis. Bone scintigram showed no abnormal RI accumulation to bone. Therefore, his prostatic cancer was considered to be at stage B2. Abdominal ultrasound echogram showed the mass lesion in the left kidney. CT and angiogram also demonstrated a left renal tumor. Left radical nephrectomy was performed and histopathology showed a mixed subtype of renal cell carcinoma (stage: pT2b, pN0, pM0). Although 94 cases of double cancers associated with genitourinary organs have been reported in the Japanese literature, only 4 cases of double cancers of renal cell carcinoma and prostatic cancer have been reported.

Intravenous immunoglobulin replacement therapy for common variable immunodeficiency during pregnancy

Patients with common variable immunodeficiency (CVID), characterized by impaired antibody production, have a high susceptibility to bacterial infections and need supplements of immunoglobulin G (IgG). We report two pregnancies in a woman with CVID. Differences in the outcome of the two pregnancies suggest the need for adjustment of replacement therapy during pregnancy.

Expression of the fibroblast growth factor receptor-1 in human normal tissues and tumors determined by a new monoclonal antibody

OBJECTIVE

To characterize the distribution of the receptor for the fibroblast growth factor in human normal tissues and tumors using a new monoclonal antibody.

DESIGN

Monoclonal antibodies for a kinase-insert region of fibroblast growth factor receptor-1 (FGFR-1) were generated. We conducted an immunohistological analysis of FGFR-1 using a highly specific antibody we generated, and we examined the distribution of this receptor in normal human tissues and in tumors.

RESULTS

Intense positivity of FGFR-1 was observed in astrocytes in the brain, smooth muscles in the uterus, cardiac myocytes, respiratory epithelium in the lung, tubular epithelium in the kidney, acinar cells in the pancreas, follicular cells in the thyroid, and ductal and lobular epithelium in the breast. We also observed FGFR-1 expression in the fibroblasts and the tissue microvasculature. In addition to some nonepithelial tumors, some epithelial tumors expressed FGFR-1, including pancreatic adenocarcinomas, thyroid papillary carcinomas, invasive ductal carcinomas of the breast, lung adenocarcinomas, renal cell carcinomas, and colonic adenocarcinomas. Although FGFR-1 was expressed in colonic adenocarcinomas, which have invasive potential, tubular adenomas, which are noninvasive, did not express FGFR-1.

CONCLUSION

We have been able to define the distribution of FGFR-1 in human normal tissues and tumors. Especially in colonic tumors, FGFR-1 expression may lead adenoma cells to invade and grow in the surrounding tissue.

[Polyorchidism: a case report and review of the literature]

An 11-year-old boy visited our department complaining of left scrotal painless mass from 6 months ago. The small mass was palpable beside the left testis. Ultrasonography shows isoechoic round shaped mass 5 mm in diameter. At surgery, the mass was connected with the left testis and epididymal head and sharply excised from them. Histological examination showed normal testicular architecture, but spermatogenesis was not found. We report the 18th case of polyorchidism in Japan and made some discussion about polyorchidism.

Blood pressure and urinary C-peptide excretion in subjects with varying degrees of glucose tolerance

To determine whether blood pressure is associated with 24-h urinary C-peptide excretion in subjects with varying degrees of glucose tolerance, we studied 247 Japanese men aged 30-69 who had never been treated with antihypertensive medications or with insulin. Plasma glucose and insulin responses during a 75-g oral glucose tolerance test, blood pressure and body mass index were obtained and urinary C-peptide excretion, in total and per kg body weight, were examined by 24-h urine collection. In monovariate analyses, urinary C-peptide excretion per kg body weight increased significantly as the blood pressure level rose (p < 0.05). After adjustment for age and body mass index by analysis of covariance, this relationship remained significant (p < 0.05), where adjusted mean values (+/- SEM) of urinary C-peptide per kg body weight were 1.56 +/- 0.05 microgram/24h/kg in the normotensive group and 2.04 +/- 0.17 microgram/24h/kg in the hypertensive (stage 2-4) group. When stratified simultaneously by glucose tolerance status and blood pressure level, adjusted mean values of urinary C-peptide per kg body weight were significantly higher in diabetic hypertensives than in diabetic normotensives. These results suggest that increase in 24-h urinary C-peptide excretion, i.e. 24-h insulin secretion, might contribute to an elevation of blood pressure both in normal and diabetic individuals.

Effects of maternal uninephrectomy on the development of the proximal tubule in fetal rat kidney: morphometrical study

The kidneys of fetal rats from uninephrectomized mothers were investigated morphometrically on days 18, 20, and 22 of gestation. Maternal uninephrectomy was performed on day 5. On days 20 and 22, the proximal tubular cell height in fetuses from uninephrectomized mothers was significantly lower than that in fetuses from sham-operated mothers. The luminal diameter, length and total volume of the proximal tubule were significantly larger in fetuses from uninephrectomized mothers than in those from sham-operated mothers. The total glomerular volume of mature type in fetuses from uninephrectomized mothers was significantly larger than that in fetuses from sham-operated mothers. On day 18, maternal uninephrectomy caused no significant difference in any kind of parameters used for the proximal tubule, but induced an increase in the total glomerular volume of immature type. These results suggest that maternal uninephrectomy stimulates morphological development of the proximal tubule in the fetal kidney.

Gag-Gag interactions in the C-terminal domain of human immunodeficiency virus type 1 p24 capsid antigen are essential for Gag particle assembly

Seven internal deletions within the p24 domain of the human immunodeficiency virus type 1 Gag precursor have been assessed for their effect on Gag particle formation following their expression using recombinant baculoviruses. In addition, each deleted molecule was assessed for its ability to bind soluble p24 antigen in vitro. The mutants fell into three different phenotypic groups: (i) three mutants that had no effect on either p24 binding or Gag particle assembly, (ii) three mutants that abolished both features and (iii) one mutant that bound p24 in vitro but failed to assemble particles. Mutations that abolished both in vitro p24 binding and particle assembly mapped to the C terminus of p24 confirming this region as critical for virion assembly. We suggest the division of virion assembly into at least two distinct phases and suggest a model in which the critical sequences mapped to date are combined with available structural information.

A novel dipeptidyl aminopeptidase from Pseudomonas sp. strain WO24

An activity similar to that of dipeptidyl aminopeptidase I (DAP I) which releases dipeptide from Gly-Arg-p-nitroanilide (Gly-Arg-pNA) was detected in a Pseudomonas sp. An enzyme was isolated and purified about 400-fold by a series of column chromatographies. The enzyme, named DAP BI (DAP from bacteria, type I), was revealed to be homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing. The molecular mass was estimated to be 82 kDa by SDS-PAGE and 65 kDa by gel filtration, suggesting that the enzyme may be a monomer. The enzyme had an isoelectric point of 4.7. It is optimally active at pH 9.0. The Km and Vmax of the enzyme for Gly-Arg-pNA were 0.25 mM and 195 micromol/min/mg, respectively. The purified enzyme did not hydrolyze Gly-Phe-pNA, which was also a substrate for DAP I, whereas it hydrolyzed Arg-Arg-4-methoxy-beta-naphthylamide (Arg-Arg-MNA), a model substrate for DAP III. The Km and Vmax for Arg-Arg-MNA were 0.019 mM and 145 micromol/min/mg, respectively. This purified enzyme can also catalyze the removal of Asp-Arg from the N termini of angiotensins I and II. The enzyme activity was completely inhibited by Zn(II) (0.5 mM), tosyl-L-Lys-chloromethyl ketone (0.1 mM), and leupeptin (0.1 mM) and partially inhibited by Co(II) (0.5 mM) and chymostatin (0.1 mM), whereas the enzyme was not affected by general serine protease inhibitors (phenylmethylsulfonyl fluoride and diisopropylfluorophosphate) and thiol protease inhibitors. The substrate specificity, classification of catalytic site, and other enzymatic properties demonstrate that this enzyme is distinct from the previously described mammalian DAPs I and III and Saccharomyces cerevisiae DAP III. These results indicate that DAP BI may be a new type of the DAP family.

Complete inhibition of human immunodeficiency virus Gag myristoylation is necessary for inhibition of particle budding

Myristoylation of human immunodeficiency virus (HIV) Gag protein is essential for virus particle budding. Two reactions are involved; activation of free myristate to myristoyl-CoA and transfer of the myristoyl residue to the Gag N-terminal glycine. We have investigated the effects of triacsin C, an inhibitor of long chain acyl-CoA synthetase, on release of HIV Gag virus-like particle (VLP) produced using the recombinant baculovirus system. First, inhibition of acyl-CoA formation by triacsin C was confirmed using the membrane fractions of insect Sf9 cells as an enzyme source. Second, when HIV Gag protein was expressed in the presence of triacsin C (0-48 microM), Gag myristoylation was inhibited in a dose-dependent manner. Budding of Gag VLP, however, did not follow similar inhibition kinetics but appeared unaffected up to 24 microM, yet was completely abolished at 48 microM when the myristoylation of Gag protein was also completely inhibited. The "all-or-none" inhibition of Gag VLP budding suggests that although inhibition of acyl-CoA synthetase blocks the production of myristoylated Gag protein, only complete inhibition of Gag myristoylation prevents VLP budding. Thus, relatively few myristoylated Gag molecules are sufficient for plasma membrane targeting and VLP budding.

Applications of retrovirus-mediated expression cloning

We have recently established a novel expression cloning system using retroviral vectors. The system is based on a high-efficiency packaging cell line, BOSC23, and a simplified retroviral vector, pBabeX, carrying no selection marker. cDNA libraries, constructed in the pBabeX vector, are transiently transfected into BOSC23 cells. The supernatant contains more than 3X10(6)/mL, which would cover large complexities of cDNA libraries. The retrovirus stock gave 100% infection efficiency in NIH3T3 cells and 5-40% infection efficiency in various hematopoietic cell lines. In contrast to the conventional expression cloning system, in which it is necessary to transfect cDNA libraries transiently into particular cell types such as COS cells, retrovirus-mediated expression cloning allows us to transduce cDNAs into a wide variety of cell types. This method therefore makes it possible to select cells expressing a cDNA of interest by various functional assays. When combined with polymerase chain reaction (PCR)-driven random mutagenesis, this system is also useful in searching for mutations of various molecules that will result in alterations of their functions.

Induction of experimental bone metastasis in mice by transfection of integrin alpha 4 beta 1 into tumor cells

Cell adhesion receptors (eg, integrins and CD44) play an important role in invasion and metastasis during tumor progression. The increase in integrin alpha 4 beta 1 expression on primary melanomas has been reported to significantly correlate with the development of metastases. alpha 4 beta 1 is a cell surface heterodimer that mediates cell-cell and cell-extracellular matrix interactions through adhesion to vascular cell adhesion molecule (VCAM)-1 and to the IIICS region of fibronectin. To test the effects of alpha 4 beta 1 expression on tumor cell metastasis, Chinese hamster ovary cells were transfected with human alpha 4 cDNA. Whereas alpha 4-negative Chinese hamster ovary cells developed only pulmonary metastasis, alpha 4-positive Chinese hamster ovary cells developed bone and pulmonary metastasis in 3 to 4 weeks when injected intravenously into nude mice. Bone metastasis was inhibited by antibody against alpha 4 or VCAM-1. Expression of alpha 3 beta 1, alpha 6 beta 1, or alpha V beta 1 did not induce bone metastasis. Expression of alpha 4 beta 1 also induced bone metastasis in K562 human erythroleukemia cells injected into SCID mice. These results demonstrate that alpha 4 beta 1 can induce tumor cell trafficking to bone, probably via interaction with VCAM-1 that is constitutively expressed on bone marrow stromal cells.

Molecular cloning and functional characterization of a novel member of the C-C chemokine family

Chemokines play an important role in immune and inflammatory responses by inducing migration and adhesion of leukocytes. We have isolated a novel chemokine cDNA, designated CCF18, from a cDNA library of an IL-3-dependent murine pro-B cell line, Ba/F3. The cDNA encodes a protein structurally related to the C-C chemokine members. Among this family, C10 shows the highest homology to CCF18, and MIP-1 alpha also has a significant homology but to a lesser extent. CCF18 produced from COS cells induced chemotaxis and Ca2+ flux in CD4+ T cell clones. Moreover, prior administration of MIP-1 alpha desensitized the cells to CCF18. The CCF18 gene (Scya10) was mapped to a middle region of murine chromosome 11, where other genes for several C-C chemokine members are localized. These results clearly indicate that CCF18 is a new member of the C-C chemokine family. Since a high level of CCF18 mRNA is constitutively expressed in macrophage and myeloid cell lines, CCF18 may play a role in inflammatory processes.

Molecular cloning and functional characterization of a novel member of the C-C chemokine family

Chemokines play an important role in immune and inflammatory responses by inducing migration and adhesion of leukocytes. We have isolated a novel chemokine cDNA, designated CCF18, from a cDNA library of an IL-3-dependent murine pro-B cell line, Ba/F3. The cDNA encodes a protein structurally related to the C-C chemokine members. Among this family, C10 shows the highest homology to CCF18, and MIP-1 alpha also has a significant homology but to a lesser extent. CCF18 produced from COS cells induced chemotaxis and Ca2+ flux in CD4+ T cell clones. Moreover, prior administration of MIP-1 alpha desensitized the cells to CCF18. The CCF18 gene (Scya10) was mapped to a middle region of murine chromosome 11, where other genes for several C-C chemokine members are localized. These results clearly indicate that CCF18 is a new member of the C-C chemokine family. Since a high level of CCF18 mRNA is constitutively expressed in macrophage and myeloid cell lines, CCF18 may play a role in inflammatory processes.

Effects of Bordetella bronchiseptica dermonecrotizing toxin on bone formation in calvaria of neonatal rats

The effects of Bordetella bronchiseptica dermonecrotizing toxin on bone formation were investigated using a purified toxin preparation. Single injection of 4.3 ng of the toxin into the subcutaneous tissue overlying the calvariae of neonatal rats necrotized periosteum of parietal bone and degenerated osteoblasts within two days. Nine days after the injection, the lesion of the bone tissue became severe; the bone matrix became thin and fragmented. These observations indicate that dermonecrotizing toxin without other factors produced by the organisms impairs bone formation.

Different migration patterns of antigen-presenting cells correlate with Th1/Th2-type responses in mice

Antibodies are produced when antigen-presenting cells (APC) pulsed with an antigen are injected intravenously (i.v.) into BALB/c mice, but subcutaneous (s.c.) injection of such APC causes delayed-type hypersensitivity (DTH). To identify the anatomic sites where T and B cells are activated, we labelled splenic dendritic cells (DC) with a fluorochrome, PKH 26, injected them i.v. or s.c., and used the label to locate them. When the DC were injected i.v., germinal centres in the spleen were hyperplastic on day 1. Most DC moved to T-dependent areas of the white and red pulp on day 1 and remained there at least until day 5, but no DC migrated into the lymph nodes. When the DC were injected s.c., they were in the sinus on day 1 and had entered T-dependent area of draining lymph nodes only by day 3; hyperplasia of germinal centres in the spleen and migration of DC into the spleen were not found. We used the polymerase chain reaction (PCR) to study which mice had spleen cells and lymph node cells that produced the cytokines interleukin (IL)-2, IL-4, IL-10, and interferon-gamma (IFN-gamma). In the sensitization phase, day 1 after DC injection i.v., almost all IL-10 transcript was found in spleen cells, but after DC injection s.c., IL-2 message was most abundant in lymph node cells. The expression of mRNA for IL-4 and IFN-gamma in mice that received DC i.v. was not different from that in mice that received DC s.c. in this phase. Immunohistochemical staining showed that cells stained for IL-10 were in the T-dependent area of the spleen from mice that received DC i.v. 1 day after the injection. Three days after the injection of DC i.v., cells stained for IL-10 were in the germinal centres as well. The number of such cells in the spleen of mice that received DC i.v. was significantly more than that in mice that received DC s.c. IL-10 may be important in development of TH2 response.

A molecular determinant of human immunodeficiency virus particle assembly located in matrix antigen p17

We report single-point mutations that are located in the matrix protein domain of the gag gene of human immunodeficiency virus type 1 and that prevent Gag particle formation. We show that mutations of p17 that abolish human immunodeficiency virus particle assembly also prevent the dimerization of p17 protein, as measured directly by a protein-protein binding assay. In the three-dimensional structure of p17, mutations that abolish dimerization are located in a single alpha helix that forms part of a fingerlike projection from one side of the molecule. Peptides derived from this region of p17 also reduce the level of p17 dimer when they are added to p17-expressing cells and compete for p17 self-association when present in protein-protein binding assays. We propose that the dimerization of the Gag precursor that occurs by the interdigitation of alpha helices on adjacent matrix molecules is a key stage in virion assembly and that the prevention of such an interaction is the molecular basis of particle misassembly.

The use of an ileostomy connector to diminish the frequency of defecation prior to ileostomy closure in patients with a pelvic pouch

A new method for allowing stool passage into the pelvic pouch before ileostomy closure to verify the defecation state and diminish stool frequency is reported herein. This was accomplished by fitting an ileostomy connector connecting the proximal and distal openings of the diverting loop stoma. The ileostomy connector was initially in place for 6 h a day, the length of time being gradually increased until it was able to be left in for 24 h a day over a 3-month period. The calculated daily frequency of stools decreased from 24 to 6 or 7 times, and the mean daily frequency immediately after ileostomy closure was 6.5 times. Physiological study also showed an improvement, with squeeze pressure increasing from 35 cmH2O to 116 cmH2O and the maximum tolerated volume increasing from 35 ml before, to 90 ml 3 months following the use of an ileostomy connector. Thus, we conclude that an ileostomy connector may be useful to predict postoperative functional outcome and its complications, and to diminish the frequency of defecation before ileostomy closure in patients with a covering loop stoma.

Morphometry on proximal tubule of the kidney in rat pups from uninephrectomized mothers

Effects of maternal uninephrectomy in rats, which was performed on day 5 of gestation, on development of proximal renal tubule of the pups were morphometrically investigated. One day after birth, both the proximal tubular length per unit volume (1 mm3) of whole kidney and total proximal tubular volume in the neonates from uninephrectomized mothers were significantly larger than those in the neonates from sham-operated mothers. Six weeks after birth, no significant differences in parameters of the kidney were observed between the pups from uninephrectomized and sham-operated mothers. These results suggest that maternal uninephrectomy in the rat accelerates the development of proximal renal tubule in the fetus and that the renotropic activity is not lasting during postnatal development of the kidney.

Malignant schwannoma of the liver

Malignant schwannoma is the most common soft tissue sarcoma in adults, but primary schwannoma of the liver is extremely rare. We report an autopsy case of malignant schwannoma of the liver in a 63-year-old man. The tumor involved almost the entire right lobe of the liver. Microscopically, it was composed of moderately pleomorphic spindle cells with hyperchromatic nuclei with mitotic figures. The spindle cells were stained positively with antibodies to both S-100 protein and vimentin. Necrosis was found in the primary tumor. Only four other cases of malignant schwannoma of the liver were found in a review of the literature. Pertinent features of these tumors are discussed.

Plasma insulin and blood pressure in normotensive Japanese men with normal glucose tolerance

OBJECTIVE

To determine whether blood pressure within the normal range is associated with plasma insulin concentration in a Japanese population with normal glucose tolerance.

METHODS

We studied 491 normotensive Japanese men with normal glucose tolerance, who had never been treated with antihypertensive medications. Plasma glucose and insulin response during a 75-g oral glucose-tolerance test, blood pressure, body mass index, serum lipids, alcohol consumption and smoking status were obtained. The subjects were divided into quartiles according to mean blood pressure level (< 79, 79-84, 85-91 and > or = 92 mmHg). To eliminate possible confounding factors, analysis of covariance was also performed.

RESULTS

In univariate analyses the plasma insulin response after an oral glucose load, especially after 60 min, was significantly related to blood pressure level. Plasma glucose was related to blood pressure level only at fasting. When adjusted for age, body mass index, plasma glucose response and alcohol consumption, plasma insulin concentrations after 30 and 60 min in the highest quartile were significantly higher than those in the lowest quartile.

CONCLUSIONS

Blood pressure was significantly and independently related to plasma insulin level after an oral glucose load in normotensive Japanese men with normal glucose tolerance. The results suggest that the relationship between blood pressure and insulin resistance already exists in a prehypertensive state even in a lean Asian population.

Mortality of inhabitants in an area polluted by cadmium: 15 year follow up

OBJECTIVE

To assess the influence of environmental exposure to cadmium (Cd) on long term outcome of inhabitants living in an area polluted by Cd.

METHODS

A follow up study for 15 years (from 1974-5 to 1991) was carried out on 2408 inhabitants (amounting to 95% of the target population, 1079 men and 1329 women) of the Kakehashi River basin in Ishikawa Prefecture, Japan. These inhabitants had been the subjects of the health impact survey in 1974-5 to evaluate (by measurement of urinary retinol binding protein (RBP)) renal dysfunction induced by Cd. Analysis of mortality was performed by dividing subjects into a urinary RBP positive (> or = 4 mg/l) group and RBP negative (< 4 mg/l) group.

RESULTS

After adjustment for age with Cox's proportional hazard model, RBP > or = 4 mg/l showed a significant relation to mortality in both sexes. At this time, the mortality risk ratio of the RBP positive to negative group was 1.71 in the men and 1.42 in the women. When the SMRs according to causes of deaths in the RBP positive group were compared with those of the RBP negative group or the overall Japanese population increases of SMR for cardiovascular diseases, especially heart failure, and renal diseases were found in both sexes.

CONCLUSION

These results suggest that the prognosis of the exposed inhabitants with renal tubular dysfunction is unfavourable, and these increases of mortality are due to heart failure and renal diseases.

Comparative study on mortality patterns in Japan and China

On the basis of the 1990 Chinese death notice data and 1990 Japanese populations vital statistical materials, the mortality patterns and proportions of individual causes of death in the two countries were compared. In both sexes, the mortality rates were the highest in almost all age groups in Chinese rural areas followed by urban areas and Japan. In Japan and in Chinese urban areas, malignant neoplasms cardiovascular diseases and cerebrovascular diseases were the major causes of death, with these three making up about 60% of the total. In Chinese rural areas, these three conditions were responsible for 43% of all deaths, a considerably lower figure as compared to those in the other two areas, and the mortality rates for infectious diseases and accident/suicide were higher than those in the other two areas. Of the three major adult diseases, cerebrovascular diseases were found to be especially frequent in both Chinese urban and rural areas. On the other hand, ischemic heart disease was found at comparable levels in Japan and China and the rate was lower than in other developed countries. Site-specific mortality rates for malignant neoplasms were characterized by high rates for lung, liver and esophageal cancers in China. The mortality rates for bronchitis in both Chinese urban and rural areas were markedly higher than those in Japan These differences in mortality rates and proportions of individual causes of death between China and Japan are thought to be attributable to the differences in medical services and the level of risk factors for each disease.

Morphometry of the kidney in rat pups from uninephrectomized mothers

BACKGROUND

The present study was designed to explore whether maternal renal dysfunction affects fetal kidney development and if the effects are lasting during the postnatal development.

METHODS

Kidneys of 1-day-old and 6-week-old pups from mothers which were uninephrectomized on day 5 of gestation were studied.

RESULTS

One day after birth, both the number of immature glomeruli and average volume of mature glomeruli of the neonates from uninephrectomized mothers were significantly larger than those from sham-operated mothers. Six weeks after birth, no significant differences in parameters of the kidney were observed between the pups from uninephrectomized and those from sham-operated mothers. Furthermore, blood urea nitrogen (BUN) concentration in adult female rats was determined at various days after uninephrectomy. BUN concentration in uninephrectomized rats was significantly higher than that in sham-operated ones.

CONCLUSIONS

These results suggest that the fetal kidney development is accelerated by the elevated BUN level following maternal uninephrectomy and that the renotropic activity does not last during the postnatal developmental period.

A multicenter, randomized, controlled trial of intravenous gamma globulin therapy in children with acute Kawasaki disease

We studied the effect of intravenous, polyethyleneglycol-treated, human immunoglobulin, administered at 200 mg/kg per day (group A: n = 147; male 86, female 61; age < 1 year, 50) or 400 mg/kg per day (group B: n = 152; male 87, female 65; age < 1 year, 52) for five consecutive days and compared it with freeze-dried, sulfonated human immunoglobulin [group C: n = 152; male 87, female 65; age < 1 year, 51), administered at 200 mg/kg per day for five consecutive days, on the prevention of coronary artery abnormalities in Kawasaki disease. Echocardiograms were interpreted blindly and independently. Proportions of 87.1%, 95.4%, and 82.3% in groups A, B, and C, respectively, had no coronary artery abnormalities. The confidence limits of difference between the proportions of groups A and C, groups B and C, and groups B and A were -4.4% and 10.4%, 7.8% and 15.9%, and 4.0% and 10.8%, respectively. Duration of fever and serum immunoglobulin G (IgG) levels were correlated with the prevalence of coronary artery abnormalities. We concluded that intravenous, polyethyleneglycol-treated, human immunoglobulin and freeze-dried, sulfonated human immunoglobulin had clinically equivalent effects on coronary artery abnormalities, and that five daily doses of 400 mg/kg of intravenous, polyethyleneglycol-treated, human immunoglobulin is more effective than that of 200 mg/kg gamma globulin.

[A study of thyroid hormone levels of inhabitants of the cadmium-polluted Kakehashi River basin]

We compared thyroid hormone levels of inhabitants (19 men and 16 women) of the cadmium (Cd)-polluted Kakehashi River basin in Ishikawa Prefecture, with those of subjects (23 men and 47 women) living in a non-polluted area. In addition, we investigated the relationships between the thyroid hormone levels and indices of renal dysfunction induced by Cd exposure. The following results were obtained: 1) The free T4 level of females was significantly lower than that of controls. 2) The T3 level of inhabitants of both sexes was significantly higher than that of controls. 3) The level of free T4 among females became lower with the increases of urinary beta 2-microglobulin (beta 2-MG), urinary protein, urinary sugar, urinary amino acids and serum creatinine (Cr) levels, and with decreases of creatinine-clearance (CCr) and %TRP. 4) We could not find any relationship between the increase of T3 and the indices of renal dysfunction induced by Cd exposure in either sex.

[Endocrine chemotherapy for prostatic cancer]

We carried out a randomized joint study on endocrine therapy and endocrine chemotherapy for prostatic cancer at our department and 17 affiliated institutions. Of 80 patients entered, 39 patients were treated with chlormadinone acetate alone (group A) and 41 patients were treated with chlormadinone acetate in combination with UFT (group B). After excluding 10 inappropriate patients, Stage C was observed in 14 patients in group A and 13 in group B, and stage D in 20 patients in group A and 23 in group B. Side effects were observed in 8.8% (3/34) in group A and 22.2% (8/30) in group B without a significant difference. The anti-tumor effects (response rate) and clinical effects with respect to each item did not significantly differ between the two groups. The non-recurrence rate and survival rate were significantly higher in group B than in group A. These findings suggest the usefulness of endocrine chemotherapy using UFT.