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Biomedical subjects

M Tajima

Publications and source records attributed to M Tajima.

At least 145 records · Page 8Linked to original sources

Biological behaviour and morphological characteristics of a transplantable tumour derived from a uterine smooth muscle tumour in the F344 rat.

A subcutaneously transplantable tumour (SMT-Y) was established from a smooth muscle tumour arising from the uterus of a female F344 rat. SMT-Y was serially passaged by subcutaneous implantation into syngeneic female rats up to the 15th generation, but transplantation failed in males. The rat with the primary uterine tumour also had mononuclear cell leukaemia (MCL), and MCL cells grew concurrently in implanted rats. At passage five, MCL cells were eliminated from transplants by implanting the central part of an SMT-Y nodule, consisting only of neoplastic smooth muscle cells. SMT-Y at passages six to 15 was examined biologically and morphologically. The primary tumour and SMT-Y tumours consisted mainly of interlacing fascicles of elongated and fusiform neoplastic smooth muscle cells with abundant cytoplasm. Occasional cells showed nuclear atypia. Mitosis counts per 10 high-power microscopic fields in the primary tumour and SMT-Y ranged from 11 to 36. Neoplastic cells reacted positively for desmin, muscle actin and myosin, but not for myoglobin. Electron microscopy revealed cytoplasmic myofilaments with oval dense bodies. These findings suggested a smooth muscle origin of SMT-Y and it was regarded as a leiomyosarcoma by the criteria for human uterine smooth muscle tumours. Despite the malignant histological features, SMT-Y grew slowly into a large nodule, with an average diameter of 5 cm and average weight of 81 g, 24 weeks after transplantation. Neither invasive tumour growth nor metastases were observed in SMT-Y-bearing rats.

Animals↗

Suppression by kampo medicines in preneoplastic mammary hyperplastic alveolar nodules of SHN virgin mice.

Sho-saiko-to (SST), Keishi-bukuryo-gan (KBG), and Shakuyaku-kanzo-to (SKT) are Japanese modified traditional Chinese herbal medicines (Kampo medicines) consisting of 7, 5, and 2 medical plants, respectively. It is known that the hyperplastic alveolar nodule (HAN) is a representative preneoplastic state in the mammary glands of mice. We examined the effects of SST, KBG, and SKT on the formation and growth of HAN in a high-mammary-tumor strain of SHN virgin mice. Oral administration of SST for 60 days beginning at 90 days of age reduced the number and area of HAN and mammary thymidylate synthetase activity with a reduction of serum prolactin level. There was little difference between the other experimental groups and the control in the formation and growth of HAN and the enzyme activities. These results indicate that SST may have a preventive effect on malignant mammary transformations.

Animals↗

Multicystic peritoneal mesothelioma in a Fischer-344 rat.

A spontaneous multicystic peritoneal mesothelioma was detected in a 108-wk-old male Fischer-344/DuCrj rat. Grossly, a tumor containing numerous, semi-transparent, variously sized, thin-walled cysts was found on the splenic serosal surface. Microscopically, each cyst was surrounded by variable amounts of loose connective tissue. The luminal and free surfaces of the cysts were covered by a single layer of flattened or cuboidal mesothelial cells. No metastases were detected in any of the other organs. Diagnosis was supported by immunohistochemistry and ultrastructural features.

Aging↗

Effects of female hormones and 3,5,3'-triiodothyronine or dexamethasone on induction of epidermal growth factor and proteinases F, D, A, and P in the submandibular glands of hypophysectomized male mice.

The effects of progesterone (Pro), 5 alpha-dihydrotestosterone (DHT), 17 beta-estradiol (E2), T3, and dexamethasone (Dex), given alone or in combination, on induction of epidermal growth factor (EGF) and proteinase isozymes in the submandibular glands of hypophysectomized mice were examined. Each hormone, except E2, acting alone had essentially comparable inductive effects on EGF concentrations and on total proteinase activity. E2 alone had no inductive effect at all. Pro acted synergistically with T3, but its inductive effect was diminished when given with Dex. E2 was not synergistic with T2, and it inhibited the effect of Dex; it also partially blocked the action of DHT on induction of proteinase activity but not of EGF. Simultaneous administration of all five hormones restored total proteinase activity completely but EGF levels to only 50% of values for intact males, respectively. Submandibular proteinases were resolved by isoelectric focusing into four isozymes: proteinase F (pI 4.8), proteinase D (pI 5.8), proteinase A (pI 6.2), and proteinase P (pI 10.0). Pro alone slightly increased levels of proteinase F but greatly raised levels of the other three isozymes. This inductive action was augmented when Pro was given with T3 but blocked when it was given with Dex. E2 alone not only failed to induce any of the isozymes, but even further reduced levels of proteinase F. It also decreased the inductive effects of T3 on these isozymes, and with Dex completely blocked induction of proteinases D, A, and P. E2 plus DHT suppressed proteinase F levels and only induced proteinase A. All five hormones together reestablished the isozyme profile seen in intact males. These results show that Pro by itself is as capable as androgens, thyroid hormone, or glucocorticoid in regulating expression of these submandibular polypeptides, and that its action can be modulated by other pituitary-dependent hormones. In addition, they demonstrate that E2 does not regulate their expression, and that it has an inhibitory effect on the inductive action of other hormones. Last, they indicate that these various hormones may regulate expression of EGF and of each of the individual proteinase isozymes differently.

Animals↗

The detection of a mutation of CD18 gene in bovine leukocyte adhesion deficiency (BLAD).

Two calves (5 and 9 months old) affected with pneumonia and gingivitis were also diagnosed as having bovine leukocyte adhesion deficiency (BLAD). The gene of leukocyte adhesion molecule CD18 in these BLAD calves and their dams (carrier) were examined by means of polymerase chain reaction (PCR) and digestion of restriction endonuclease. The splicing in mRNA coded CD18 reported in human LAD was not recognized in BLAD on the basis of the results of PCR amplification. The region including the portion of point mutation, which corresponded to the region reported in the human patient, was amplified by PCR, and the PCR product was then digested with Taql. An obvious difference was recognized in the pattern of digestion among healthy calves, BLAD calves and their dams. In BLAD, therefore, the point mutation reported in human patients was strongly suggested. Moreover it may be a method able to be used in detecting the carrier.

Animals↗

Unilateral atrophy of the optic nerve associated with retrograde and anterograde degenerations in the visual pathways in Slc: Wistar rats.

Unilateral degenerative atrophy of the optic nerve (ON) occurred in 6 of 80 male and 4 of 80 female Slc: Wistar rats. Two of these cases completely lost the intracranial portion of the unilateral ON and the remainder had the small ON. The optic disc and ON were located histologically in the posterior pole of the eyeball of 2 rats with no intracranial ON. ON lesions in all cases were characterized by a reduced number of axons with a small number of myelinated axons and marked astrogliosis. There were also swelling, fragmentation and spheroid formation of axons, as well as thickening of the connective tissue sheaths and vessel walls in the ON. One side of the optic chiasma and optic tract contralateral to the affected ON reduced in volume, became degenerated and were accompanied by gliosis. Focal or diffuse degeneration of the retina was observed in the eyeballs with affected ON. Retinal ganglion cells decreased in the number showing chromatolysis. These retinae became thin and developed degeneration of both inner and outer portions with sclerotic changes in the retinal vessels. The ophthalmic and ciliary arteries in the eyeballs with affected ON often developed proliferative or occlusive endoarteritis, suggesting that retinal lesions may have resulted not only from axonal degeneration in the ON but also from ischemia. Histologic lesions suggestive of transneuronal degeneration were found in the contralateral lateral geniculate body and rostral colliculus. Based on the data presented, it was presumed that a primary lesion may have been induced in the ON by a circulatory disturbance and followed by retrograde and anterograde degenerations in the visual pathways.

Animals↗

[Invention of an air forced ventilated micro-isolation cage and rack system--environment within the cages: ventilation, air flow].

A forced air ventilation system for small laboratory animals was developed. The system consists of an air handling unit with air supply and exhaust fans, a rack, hard cage covers with a large diameter air inlet and an outlet, and shoe box cages. Air flow from the supply duct, to the exhaust duct and within the cage were observed. Variations in air flow among cages was minimal. The optimal air exchange rate of the cages in this system was determined to be 60 times per hour based on the results obtained in the present study. At this air exchange rate, air flow at the base of the cages had a velocity of less than 0.09m/sec, which was within the range of recommended values for humans. The observed results show that the system developed is capable of sustaining a laboratory animal microenvironment well in terms of air flow, without too much energy cost.

Air Movements↗

Spin-trapping and chemiluminescence studies of neutrophils from a Holstein-Friesian calf with bovine leukocyte adhesion deficiency.

The ability of neutrophils from a Holstein-Friesian calf with bovine leukocyte adhesion deficiency (the proband with a genetic deficiency of the Mac-1 (CD11b/CD18) glycoprotein corresponding to the receptor of complement iC3b) to generate oxygen radicals was examined using electron spin resonance spectrometry (ESR) combined with a spin-trapping technique and luminol-dependent chemiluminescence spectrometry. When the neutrophils were stimulated with phorbol 12-myristate 13-acetate (PMA), an ESR spectrum confirming the generation of superoxide anions (O2-) was clearly observed in both healthy and diseased calves. However, when the neutrophils were stimulated by opsonized zymosan, appearance of the ESR spectrum was recognized in the healthy calves but not in the diseased calf. Similar results were obtained from chemiluminescence experiments.

Animals↗

Detection of JC virus in the brains of aged patients without progressive multifocal leukoencephalopathy by the polymerase chain reaction and Southern hybridization analysis.

Ninety-one brain tissue sections taken at autopsy from 33 elderly patients (63-100 years old) without progressive multifocal leukoencephalopathy were examined for the presence of JC virus DNA by the polymerase chain reaction and Southern hybridization analysis after DNA extraction. JC virus DNA was detected in 15 sections from 10 patients. These results suggest that JC virus is frequently present in the brains of aged patients.

Aged↗

Morphological characteristics of a transplantable nephroblastoma (NB-Y) in F344 rats and the relation of tumour growth to hyper-reninaemia in NB-Y-bearing rats.

A transplantable tumour, designated NB-Y, was established from a spontaneous nephroblastoma in an F344 rat. NB-Y was serially passaged in syngeneic rats by subcutaneous implantation up to the 49th generation. The transplants grew into nodules with an average diameter of 5 cm and average weight of 92.9 g 4 weeks after implantation. The primary tumour and NB-Y consisted mainly of sheets or clusters of undifferentiated blastemal cells, which reacted immunohistochemically for vimentin but not for keratin. Renin-containing cells were observed in the small blood vessel walls within the primary tumour, but neoplastic cells of both primary tumour and NB-Y failed to stain for renin. Plasma renin activity was significantly higher (40.7 ng per ml per h) in transplanted rats 4 weeks after implantation compared with non-transplanted controls (28.0 ng per ml per h). Hyperplastic juxtaglomerular cells were often observed in rats bearing NB-Y. Sinusoidal dilatation was present in the liver, adrenal glands, pituitary gland and bone marrow of recipients, suggesting abnormal blood flow provoked via the renin-angiotensin system. The present study revealed the development of hyper-reninaemia in NB-Y-bearing rats, but its pathogenesis remains unknown.

Anemia↗

Diabetes mellitus in cattle infected with bovine viral diarrhea mucosal disease virus.

Four Japanese black cattle and four Holstein-Friesian cows were diagnosed with diabetes mellitus. Based on intravenous glucose tolerance tests, all these animals were believed to be insulin-dependent diabetics. Moreover, bovine viral diarrhea-mucosal disease (BVD-MD) virus was isolated and mucosal lesions and diarrhea were recognized in all cases. There was no genetic relation among the affected cattle. The breeding places of these cattle were different to each other. Therefore, it is suggested that BVD-MD virus induced the diabetes mellitus.

Animals↗

Stimulation of IgM production in human-human hybridoma HB4C5 cells by chitosan.

We screened for immunoglobulin production stimulating factors (IPSFs) in polysaccharides using human-human hybridoma cells, HB4C5, cultured in serum-free medium. Among polysaccharides, citrus pectin, locust bean gum, and chitosan stimulated IgM production of HB4C5 cells. Especially chitosan showed the strongest IPSF activity; 100 ng/ml of chitosan stimulated IgM production approximately 5-fold. Chitosan had several characteristics as IPSF, as follows. 1) For the IPSF activity, 70-90% deacetylation was essential. 2) Chitosan oligomers (n = 5, 6, 7) and chitin oligomers (n = 5, 6, 7) showed no IPSF activities. 3) The IPSF activity of chitosan was inhibited by glucosamine, one of the constitutive sugars of chitosan. 4) Chitosan stimulated IgM production of human lymphocytes in serum-free culture, but not IgG or IgA, nor in serum-supplemented culture.

Cell Line↗

Isolation and serial propagation of porcine epidemic diarrhea virus in cell cultures and partial characterization of the isolate.

Porcine epidemic diarrhea virus (PEDV) was isolated in Vero cell cultures from the small intestine of a piglet experimentally infected with porcine coronavirus 83P-5, that had been isolated during outbreaks of porcine acute diarrhea and passaged in piglets. The isolation of the PEDV was successful only in Vero cells maintained in the maintenance medium (MM) containing trypsin. Infected Vero cell cultures exhibited CPE characterized by cell-fusion and syncytial formation, as well as cytoplasmic fluorescence when examined by the indirect immunofluorescent test using rabbit anti-83P-5 virus serum. The isolate was adapted to serial propagation in Vero cell cultures by adding trypsin to MM. Vero cell-adapted PEDV was successfully propagated in the MA104, CPK and ESK cell lines in the presence of trypsin in MM. Vero cell-adapted PEDV had morphologic and physicochemical characteristics similar to those of other members of the coronaviridae. The isolate differed serologically from porcine transmissible gastroenteritis (TGE) and porcine hemagglutinating encephalomyelitis viruses, and no antigenic relationship between the isolate and TGE virus could be detected by the indirect immunofluorescent test. Attempts to isolate PEDV in 6 types of primary fetal pig cell cultures and 6 of 10 established cell lines resulted in the failure, probably because these cells were damaged by the action of trypsin.

Animals↗

[Prostatic carcinoma presenting as an abdominal mass: a case report].

Prostatic carcinoma presenting as an abdominal mass is a very rare disorder. A 64-year-old man was referred to our hospital with the chief complaint of a right lower abdominal mass on March 6, 1984. Physical examination revealed a firm, smooth, fixed, non-tender, pulseless fist size mass in the right lower abdomen. Rectal examination revealed an apple size, smooth and elastic firm prostate which had an induration. Needle biopsy of the prostate showed well-differentiated adenocarcinoma. At first we regarded the abdominal mass as retroperitoneal tumor unassociated with prostatic carcinoma. After preoperative irradiation (20 Gy) to the pelvis, the abdominal mass was resected and bilateral orchiectomy was performed on April 11, 1984. The mass was histologically diagnosed as a metastatic lesion from prostatic carcinoma. On the basis of these findings, we considered the mass to be due to pelvic lymph node metastasis from prostatic carcinoma. His postoperative course was uneventful. In April 1991, he is still alive without evidence of recurrence or bone metastasis.

Adenocarcinoma↗

[A case of ureteral endometriosis; the usefulness of MRI for preoperative diagnosis].

A rare case of ureteral endometriosis is reported. A 46-year-old nulliparous woman was referred to our hospital because of right hydronephrosis which was detected by ultrasonography; Drip infusion pyelography showed right hydroureteronephrosis with the distal obstruction. MRI demonstrated right ovarian endometriosis and resultant ureteral stricture. Based on these findings, we made a preoperative diagnosis of right ureteral endometriosis. Right partial ureterectomy and ureteroureterostomy were performed. Pathological examination of the resected segment showed endometrial tissue around the ureteral lesion. She was administered LH-RH agonist (buserelin); her postoperative course was uneventful. IP showed no abnormalities 6 weeks after the operation. To our knowledge, this case is only the 55th case reported in the literature in Japan.

Endometriosis↗