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The intracellular localization of the avian myeloblastosis virus (AMV) genome was studied. Nuclear and mitochondrial DNAs from myeloblasts were examined by hybridization with 32P labeled AMV-RNA of high molecular weight for the presence of virus specific DNA sequences. Nuclear DNA (nDNA) from myeloblasts specifically hybridized with viral RNA, whereas purified closed circular mitochondrial DNA (mtDNA) did not hybridize with viral RNA. It was therefore concluded that viral genome was present in nuclear DNA and not in mitochondrial DNA. Likewise, in normal chick cells, nDNA but not mtDNA hybridized with viral RNA.

Deoxyuridine suppression tests have been performed by two different methods of six normoblastic and eight megaloblastic marrows. A good correlation was obtained between the results by the modified and the original methods. The simplified method was found to be applicable for a clinical purpose to diagnose megaloblastosis in the marrow. Uptake of 3H-deoxyuridine into DNA and effect of various concentrations of thymidine was studied on five normoblastic and six megaloblastic marrows. In megaloblastic marrows, a greater amount of thymidine was required to obtain the same rate of suppression of 3H-deoxyuridine incorporation into DNA than in normoblastic marrows. Impairment of thymidine incorporation into DNA in megaloblastic marrows was not revealed. Therefore, lower rate of suppression of 3H-deoxyuridine by thymidine in megaloblastic marrows may be due to impairment of the incorporation of deoxyuridine before the addition of thymidine.

Rat kidney endothelial cell morphology was examined after introducing iron colloid particles of positive or negative charge to investigate the relationship between the electric charge and permeation through the glomerular capillary. The kidneys were first perfused with Hanks' solution through the renal arteries and then with iron colloid particles of positive or negative charge. The iron colloid particles of positive charge were prepared with ferric chloride and cacodylate solutions, and the negative particles were prepared with iron chondroitin sulfate colloid particles. The iron colloid particles of positive charge adhered to the surface of endothelial cells of the glomerular capillaries, as well as the arterioles, capillaries and venules. Some particles were taken up by pinocytosis, accumulated in the glomerular basement membrane and appeared in the urinary spaces passing through the filtration slits of podocytes. Iron colloid particles of negative charge neither adhered to the endothelial cells nor were taken by the cells. They did not permeate into the urinary spaces. Permeation into the tubular lumen through the peritubular venules was not observed with particles of positive or negative charge.

Salmonella typhimurium was invariably isolated from our J strain murine leukosis. Immunization of D103 mice with either inactivated Salmonella typhimurium or the cell-free extract of leukosis inhibited the transplantation of leukosis. The adoptive immunization of D103 mice with spleen cells of Strong A mice immunized with either Salmonella or the cell-free extract of leukosis inhibited the transplantation of leukosis. The addition of either Salmonella or the cell-free extract of leukosis inhibited the migration of macrophages of leukosis spleen in tissue culture. Strong A mice is non-susceptible to J strain leukosis. However, inoculation of neonatal Strong A mice with the cell-free extract of leukosis produced a susceptibility to the transplantation of leukosis. These results suggest that both a filtrable agent and Salmonella typhimurium are present in cells of this leukosis and might be etiologically related to the leukosis.

Isolated hepatic cells from adult rats were prepared by perfusing the livers with trypsin. The highest yield of viable cells was obtained by perfusing the liver with 0.1% trypsin, pH 7.0, at 37 degrees C for 30 min. Following this treatment about 70% of cells excluded trypan blue. The isolated cells contained many binucleate cells. Between 60 and 70% of DNA present originally in the liver was recovered from the isolated hepatic cells, which had higher glucose 6-phosphatase activity than the liver. Thus the resulting cell population seems to be rich in hepatocytes. The isolated hepatic cells, however, lost some of their cellular proteins such as alanine and tyrosine amino-transferases. It was suggested that the membranes of isolated hepatic cells might be damaged by both enzymatic digestion and mechanical destruction.

Viral nucleoprotein complexes were extracted from nuclei of permissive cells (CV-1) infected with simian virus 40 (SV40) and examined by electron microscopy. SV40 nucleoprotein complexes (SV40 chromatin) showed nucleosomes in linear bead-like arrangements along the extended closed circular DNA. The contour length of the SV40 chromatin was only 1.0-1.8 times shorter than that of viral DNA obtained after deproteinization. The data suggest that the circular DNA in SV40 chromatin can be extended to nearly its full length without detachment of the histone complexes.

A case of uterine adenomatoid tumor in a 47-year-old female was studied with both light and electron microscopes. The tumor was circumscribed, 2.5 cm in diameter, and located in the posterior wall of the uterus. In light microscopy, tumor cells showing "signet-ring" appearance arranged in cords or tubules. Hyaluronidase-sensitive acid mucopolysaccharide was present in the cells and luminal surfaces. Mucicarmine stain was negative and periodic acid-Schiff reaction was faintly positive. In electron microscopy, the tumor showed basal laminae, well-developed desmosomes and numerous microvilli. Intercellular spaces were present between adjacent cells. Small intercellular spaces were separated from the large lumens by desmosomes and tight junctions, while large spaces communicated with the tubular lumens. Forty-four reported cases of adenomatoid tumor in females were briefly reviewed.

With the recent advances in the immunological surveillance system, an understanding of the role of host immunity has become essential to the management of carcinogenesis, tumor proliferation, recurrence and metastasis. Although it is important to continue chemical and surgical treatment of cancer, support of the anti-tumor immune system of the host should also be considered. Long term remission has been reported in leukemia by treating with BCG after chemotherapy whereas surgical treatment is usually more effective in preventing cancer recurrence in digestive organ cancer. The first step is extirpating the tumor as thoroughly as possible and the second step is chemo-immunotherapy. Cancer immunity, however weak, constitutes the basis for other treatments in selectively attacking cancer cells remaining after surgery, chemotherapy or irradiation. Immunotherapy should thus not replace chemotherapy or radiotherapy, but these methods should be employed in combination to attain more favorable results.

Human KC cell monolayer inoculated with concentraten Mason-Pfizer monkey virus (MPMV) showed syncytia formation within an hour. The cell fusion was blocked by the treatment of the MPMV with neutralizing antiserum. Treatment of the MPVM with beta-propiolactone resulted in the loss of infectivity although KC cell fusion ability of the virus still remained. KC cells inoculated with unconcentrated MPMV showed no cell fusion even after several transfers, although a chronic MPMV infection was established. The virus-producing KC cells were refractory to fusion by MPMV. Human embryonic lung cells (HEL) were infected by serially diluted MPMV harvested from virus-producing culture, transferred twice, then cultivated together with KC cells for syncytia formation to examine the end point dilution titer of the virus. HEL infected by 10(-4)-diluted MPMV still induced syncytia formation by cocultivation with KC cells.

The chemotactic activity of granulocytes obtained by the Terumo Filtration Leucapheresis System (F.L.) was examined by the method of Boyden's chamber. The number of cells migrating through the Millipore filter was expressed as the chemotactic activity. The mean values were 117 for the F.L. and 122 in a control, in which cells were collected from the same donor blood using dextran sedimentation. The results suggested that the in vitro chemotactic function of granulocytes obtained by F.L. was within normal limits.

To investigate the role of folic acid deficiency in the pathogenesis of anemia in the elderly, hematological examinationa and assays of serum iron, vitamin B12 and folate were carried out on the 86 elderly patients admitted to a home for the aged. Means of red blood cell counts, hemoglobin levels and hematocrit were 385.3 x 10(4)/mm3, 12g/dl and 36%, respectively. These levels were lower than any other report in Japan. Anemia was detected in 23 out of 86 patients. Judging from mean corposcular volume and mean corposcular hemoglobin, most of them were normocytic and normochromic. Although low serum levels of iron and folate were rather frequently observed, the results on hematological examinations suggest that deficiency of these factors alone is not the cause of the anemia in the elderly patients. Rapid clearance of 5-methyl-tetrahydrofolic acid and increased excretion of formiminoglutamic acid after histidine loading were revealed in some of those who had subnormal serum folate levels. Therefore, supplementation of folic acid is recommended to those who had poor dietary intake.

 To determine whether the predominant infiltration with memory CD4⁺T cells in joints is specific to the local immune and inflammatory response in rheumatoid arthritis (RA), the proportions of CD45RA⁺ or CD45RO⁺ cells in the CD4⁺T cell populations in three different compartments (i.e., peripheral blood, synovial fluid, and synovial tissue) from patients with RA and osteoarthritis (OA) were compared by two-color flow-cytometric analysis. In the CD4⁺T cell population of peripheral blood, the number of CD45RO⁺ cells was relatively higher than CD45RA⁺ cells in both RA and OA patients, but their percentages did not differ from those found in healthy individuals. However, the great majority of CD4⁺T cells present in synovial fluid and synovial tissue were CD45RO-positive and CD45RA-negative in both patient groups; although CD4⁺T cells infiltrating both the disease compartments were markedly greater in RA joints, their mean percentages of CD45RO⁺ cells were not significantly different from those in OA joints. These data indicate that an accumulation of CD45RO⁺ memory CD4+T cells is a generalized phenomenon during local inflammatory responses in both RA and OA joints, and may be due mainly to the propensity of these cells to preferentially transmigrate into the inflamed joint via adhesion molecules as compared with CD45RA⁺ naive CD4⁺T cells.

 This study was conducted to evaluate the frequency of DNA transfection into human cells following X-ray irradiation. We transfected plasmid DNA (pSV2neo) into human cells, HeLa and PA-1, by either calcium phosphate precipitation or the lipofection method immediately after irradiating the cells with various doses of X-rays. The transfection frequency was evaluated by counting the number of G418-resistant colonies. When circular plasmid DNA was used, irradiation up to a dose of 2 Gy dose-dependently increased the transfection frequency, which reached a maximum of 5 to 10-fold that of the control unirradiated cells. When linear plasmid DNA was used, the transfection frequency was 2 times higher than that of circular DNA. All five of the clones that were randomly chosen expressed the transfected neo gene. In addition, the pSV2neo gene was randomly integrated into the genomic DNA of each clone. These findings indicate that X-ray treatment can facilitate foreign DNA transfer into human cells and that radiation-induced DNA breaks may promote the insertion of foreign DNA into host DNA. The enhancement of DNA transfection with X-rays may be instrumental in practicing gene therapy.

Malignant lymphoma was induced in Japanese (JWY), New Zealand (NZY) and Dutch (DUY) white rabbits by oral spray of cell-free pellets of culture fluid (crude virus fraction) of Ts-B6 cells (cynomolgus monkey B-lymphoblastoid cells harboring Epstein Barr virus-related simian herpesvirus or Cyno-EBV). Nine of 11 inoculated rabbits developed malignant lymphomas within 42-160 days after oral inoculation (JWY, 2/3; NZY, 5/6; DUY, 2/2). In contrast, none of the control rabbits inoculated in the same fashion with B95-8 (EBV-producing marmoset cell line) cell-free pellets developed malignant lymphoma. Most rabbits showed increased anti-VCA IgG and anti-EA-DR IgG antibody titers after inoculation by oral spray of Ts-B6 cell-free pellets. EBV-encoded RNA-1 was revealed in the tumor cells by in situ hybridization. EBV DNA was detected in the rabbit peripheral blood leukocytes (PBL) by polymerase chain reaction; the earliest positive result was obtained only two days after oral inoculation. These data suggest that orally administered Cyno-EBV in Ts-B6 cells infects PBL and then induces malignant lymphoma in rabbits. The availability of this animal model promises to clarify the role of EBV in human lymphoma and provides a means for studying prophylactic and therapeutic regimens.

Physiological strain plays an important role in maintaining the normal function and metabolism of bone cells. It is well known that the mineral content of astronauts' bones decreases during spaceflight. Thus, gravity is one of the important factors in the muscloskeletal system. The vector-free horizontal clinostat has been used to simulate conditions of microgravity for examining such effects on cells in culture. We analyzed the effects of simulated microgravity using a horizontal clinostat on cultured osteoblast-like cells (HuO9 cell line). Total cellular protein, which was measured as an indication of cell proliferation, was not significantly inhibited under simulated microgravity conditions. No morphological changes were detected under microgravity conditions by phase-contrast microscopy. However, the alkaline phosphatase (ALP) activity and osteocalcin production of the HuO9 cells decreased significantly under microgravity conditions. Our data indicate that simulated microgravity directly inhibits some differentiation phenotypes and some functions of osteoblasts. On the other hand, the addition of 1,25-dihydroxy-vitamin D₃ (1,25-(OH)₂-D₃) increased ALP activity under simulated microgravity conditions, although the total activity of ALP in the cells treated with 1,25-(OH)₂-D₃ was still lower under simulated microgravity conditions than that in the control cells. However, the cells under simulated microgravity conditions showed a greater enhancement of ALP activity by treatment with 1,25-(OH)₂-D₃.

We have established an Adriamycin (ADM) -resistant small cell lung cancer (SCLC) cell line, SBC-3/ADM100, which shows multifactorial mechanisms of resistance to ADM, such as overexpression of P-glycoprotein, an enhanced detoxifying system and a decrease in topoisomerase II activity. In the present study, we confirmed that SBC-3/ADM 100 showed collateral sensitivity to methotrexate and TNP-351, a new antifolate, though this cell line showed a typical multidrug resistance (MDR) pattern. We also demonstrated a faster uptake and higher accumulation (1.3-fold) of TNP-351 in the SBC-3/ADM100 cells than those in the parent SBC-3 cells. These results explain one of the mechanisms for collateral sensitivity in the resistant cells. Furthermore, this cell line was found to have no cross-resistance to edatrexate and minimal cross-resistance to trimetrexate, 254-S (cisplatin analog), 5-fluorouracil and 4-hydroperoxyifosfamide. These drugs will have clinical importance in patients with SCLC who were previously treated with an ADM-containing regimen. Thus, antifolates, especially TNP-351 and edatrexate, can be expected to eradicate residual multidrug resistant SCLC cells selected by ADM.

We compared the transfection efficiency of four types of positively charged liposomes composed of (i) N-(α-trimethylammonioacetyl)-didodecyl-D-glutamate chloride (TMAG), dilauroylphosphatidylcholine (DLPC), and dioleoylphosphatidylethanolamine (DOPE) (1:2:2 molar ratio); (ii) 3β [N-(N′, N′-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) and DOPE (3:2 molar ratio); (iii) dimethyldioctadecylammonium bromide (DDAB) and DOPE (1:2.2 molar ratio); (iv) N-[1-(2,3-dioleyloxy) propyl] -N,N,N-trimethylammonium chloride (DOTMA) and DOPE (1:1, w/w; lipofectin). Luciferase gene was used as a reporter gene. Among the cationic liposomes used, the liposomes composed of TMAG, DOPE and DLPC showed a much higher efficiency of plasmid DNA entrapment than the other cationic liposomes tested. In the absence of serum, the cationic multilamellar vesicles (MLV) and small unilamellar vesicles (SUV) composed of TMAG, DOPE and DLPC gave highly efficient transfection. On the other hand, MLV, dehydration-rehydration vesicles (DRV), and SUV liposomes prepared with the mixtures of DC-Chol and DOPE showed similar levels of transfection efficiency. However, the cationic liposomes composed of DDAB and DOPE showed inferior efficiency, whether in the form of DRV, SUV or MLV. The transfection efficiency of lipofectin was also low. In the presence of serum, on the other hand, a considerable (about 30-50%) amount of transfection activity was still observed at 10% fetal calf serum in the cationic MLV and SUV composed of TMAG, DOPE and DLPC. Cationic MLV, composed of TMAG, DOPE and DLPC, can transfect plasmid DNA, not only in the adherent cell lines but also in the suspension cell lines. These findings indicate that the transfection efficiency of cationic liposomes is affected by the lipid composition, the type of liposome, or the presence or absence of serum. They also indicate that the cationic liposomes containing TMAG, DOPE and DLPC are efficient vectors for gene transfer into cells.

Accurate assessment of elbow function is important to determine the total ability of the arm. The purpose of this study was to clarify the relationship between isometric muscle strength of the elbows of patients with rheumatoid arthritis (RA) and Larsen's X-ray evaluation. Fifty-six elbows of 45 RA patients aged 47 to 77 years (mean age, 63 years) were tested. Muscle strength was measured with an isometric torque-cell dynamometer. Test-retest reliability of the dynamometer was proven by measuring 12 elbows of 6 healthy young men. In RA patients, elbow flexion and extension strength decreased in proportion to increases in the severity of Larsen's grades from Grade 1 to 4. However, Grade 5 elbows had greater muscle strength than those in Grade 4. Forearm pronation and supination strength also decreased in proportion to increases in the severity of Larsen's grades from Grade 1 to 5. This quantitative study made it clear that the muscle strength of RA patients' elbows almost completely correlates to X-ray finding according to the grade of Larsen's evaluation based on X-rays. With regard to muscle strength of postoperative elbows, both flexion strength and supination strength after total elbow replacement (TER) were about two times greater than before TER, and after synovectomy it was as great as those in non-operative RA patients of Grade 2.

The expression of osteonectin (ON) in osteoarthritic articular cartilage was investigated by enzyme immunohistochemistry and colloidal gold immunoelectron microscopy. A total of 96 specimens from 9 knees of 8 patients with osteoarthritis (OA) were examined. In OA cartilage, ON-positive cells varied in distribution and were not seen in all the specimens obtained from the same patient. However, in over half of the specimens (56 of 96), especially in the specimens of Mankin's grades from 4 to 9, which corresponds to relatively early stages of OA, ON was expressed in the cartilage above the calcified layer. On the other hand, ON was detected only in the calcified layer below the tidemark in normal articular cartilage. In addition, colloidal gold immunoelectron microscopy revealed ON in chondrocytes and matrix vesicles (MVs). These findings suggest that ON acts through MVs in the early stages of OA as a significant pathogenetic factor involved in intracartilage calcification, which is known to have a close relationship to the progression of OA.

We used a yeast functional assay (functional analysis of separated alleles in yeast: FASAY) to determine the p53 gene status of human cell lines maintained in our laboratory. This assay enables the researcher to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS 3 via the p53-responsive GAL 1 promoter in Saccharomyces cerevisiae. The cell lines examined were ten hepatoma, two hepatoblastoma, three in vitro immortalized fibroblast, two osteosarcoma, a chondrosarcoma, an ovarian teratocarcinoma and a colon cancer cell line. Out of 20 cell lines, 11 cell lines had mutations in both alleles of the p53 gene, and another 8 cell lines had no mutation in the p53 gene. Thus, 55% of the cell lines examined had mutations in the p53. Interestingly, PA-1 cells had both the normal and the mutant p53 alleles, showing that FASAY is a useful method for detecting the wild-type and mutated p53 genes simultaneously. As for the three liver cell lines harboring HBsAg, there was no relationship between their p53 gene status and the presence of HBsAg. Two cell lines were normal for p53 status, while the other had a mutation of the p53 gene.