Apoptosis in the central nervous system of developing mouse fetuses from 5-azacytidine-administered dams

To determine the effect of 5-azacytidine (5 Az), a cytidine analogue, on the developing fetus, different strains of mice were injected with various doses of the agent, ip, at 11 days of gestation. Light microscopically, severely pyknotic cell death profiles were observed in different layers of the developing brain and spinal cord (central nervous system) on the day after the injection. Electron microscopy of the pyknotic cells revealed the shrinkage of the cell body, to various degrees margination of the nuclear chromatin, condensation of nuclear materials, fragmentation of the affected cells, and, finally, neat "bite-size" bodies engulfed by surrounding normal neuroepithelial cells and macrophage-like cells. DNA fragmentation was detected in the nuclei of the pyknotic cells by an in situ detection method for fragmented DNA ends. These changes were consistent with the criteria of apoptosis.

Identification and minisatellite linkage analysis of SMXA recombinant inbred strains of mice by DNA fingerprinting

SMXA recombinant inbred (RI) strains of mice were produced by systematic inbreeding from the F2 generation of a cross between two progenitor inbred strains, A/J and SM/J, which differ considerably with respect to many characteristics, and consists of 28 inbred strains. In this study, we investigated the applicability of DNA fingerprinting with M13 phage DNA to the identification of these closely related strains. DNA fingerprints of the SMXA RI strains and their progenitors, SM/J and A/J, showed strain-specific patterns, with the same banding patterns within each strain. Linkage analysis by using strain distribution patterns of minisatellite loci with 108 genetic markers containing microsatellites, biochemical and immunological marker genes allowed 23 minisatellite loci to be assigned to 11 chromosomes. The results suggested that DNA fingerprinting with M13 phage DNA is applicable not only for strain identification but also for genetic monitoring of RI strains on almost all chromosomes.

Erythroleukemia in two cats naturally infected with feline leukemia virus in the same household

Erythroleukemia was observed in two unrelated cats infected with feline leukemia virus (FeLV) from the same household. Case 1, a 1-year-old neutered male cat developed erythroleukemia (M6) after a diagnosis of myelodysplastic syndrome (MDS-Er) on the criteria of FAB classification of acute leukemias. Case 2, a 1-year-old neutered female cat, which had close contact with Case 1, also developed erythroleukemia (M6Er). In both cases, marked proliferation of erythroid progenitor cells with disproportionally large numbers of immature forms was observed in the bone marrow. In Case 1, neoplastic proliferation of myeloid cells in the bone marrow was also noted at the terminal stage. Combination chemotherapy with daunomycin was partially effective for treatment of these erythroid neoplasias, but did not induce complete remission. Southern blot analysis using exogenous FeLV-specific probes indicated the clonal origin of these hematopoietic tumor cells. Furthermore, the erythroid and myeloid tumor cells in Case 1 were shown to be derived from independent transformed clones. A variant FeLV was shown to be integrated into the tumor cells in Case 1, while a full-length FeLV was found in both cases. Because these erythroid neoplastic diseases occurred in two unrelated cats kept in the same household and these diseases are rare, they may both have been associated with the same FeLV strain.

Nucleotide sequence of the SrRNA gene of Entamoeba gingivalis: applications for construction of a species-specific DNA probe and phylogenetic analysis

The small subunit ribosomal RNA (SrRNA) gene of Entamoeba gingivalis was amplified by PCR and the product of 1.9-kbp sequence was cloned into a plasmid vector pUC18. Four clones were isolated and sequenced. The insert DNAs were 1918- to 1921-bp long and A+T rich (65.5%). The four SrRNA sequences of E. gingivalis were found to be aligned with those of nine related protozoans while searching for E. gingivalis-specific sequences. A sequence of 28 oligonucleotides was chosen, chemically synthesized, and labeled with digoxigenin for use as a DNA probe. The probe thus constructed was shown to hybridize only with either the SrRNA-coding DNAs or the cells of the two E. gingivalis strains and not with those of other protozons or oral fungi tested. A representative SrRNA-sequence was analyzed and a phylogenetic tree was constructed by the neighbor-joining (NJ) method. Among the protists examined, E. gingivalis was placed next to Entamoeba histolytica as expected from the traditional taxonomy.

Separation of outer cysts from metacercariae of Fasciola gigantica in an aqueous two-phase system

The outer cysts (Oc) of Fasciola gigantica metacercariae (Mc) were separated in an aqueous two-phase system composed of polyethylene glycol and dextran in distilled water. A large number of separated Mc without Oc were recovered in the bottom layer rich in dextran in the system. Ten separated Mc in the layer were used to inoculate the mouse with a syringe and juveniles were recovered from the animals on the 14th day. When the number of juveniles recovered was compared with that from the mice infected orally with the same number of Mc, there was a significant difference between them (P < 0.05). The former method is easier than the latter for inoculation.

Cloning of canine osteosarcoma cells

Six clonal cells were established from a canine osteosarcoma cell line (POS) by a limiting dilution method using feeder cells. Whereas histology of mass developed in nude mice by transplantation of POS cells revealed various cell types, clonal cells were morphologically consistent in size and shape. Doubling time of clonal cells ranged from 30 +/- 1.4 to 54 +/- 1.3 hr and alkaline phosphatase activity ranged from 0.040 +/- 0.001 to 2.61 +/- 0.435 mumol/min/mg protein depending on the cell types. When transplanted into nude mice, each clonal cell type formed following four histological types; osteoblastic, chondroblastic, fibroblastic, and undifferentiated types. Since each histological feature was found simultaneously in the primary tumor, osteosarcoma tissue might be a complex of various types of cells having different characteristics. Therefore, POS clonal cells may be useful as a potential tool for the studies of differentiation, phenotypic expression, and a new therapeutic modality of osteosarcoma.

[Lymphatics of the thoracic surface of the diaphragm especially located around the inferior surface of the pericardial sac]

The lymphatics on the thoracic surface of the diaphragm, especially lying around the lateral and posterior sides of the base of the cardiac sac, were examined in 68 adult Japanese cadavers macroscopically (37 males and 24 females, aged 45-92 years, no clinical evidences of neoplasms). In this observation, a vein which drained into the terminal portion of the inferior vena cava was observed. The lymph nodes in this region were located along the vein frequently (80.9%). The vein passed through the esophageal hiatus, or penetrated the diaphragm and finally communicated with veins around the esophagogastric junction. However, lymphatic vessels were not observed passing through the phrenico-esophageal membrane and/or the diaphragm. The collecting vessels, which originated from the lymphatics, drained into the esophageal lymphatics, and it drained into the thoracic duct via the esophageal lymphatics. In pleural effusion cases, lymphatic nets were clearly observed on the thoracic surface of the diaphragm immediately under the parietal pleura. The lymphatic nets did not communicate with the diaphragmatic lymphatics around the base of the cardiac sac. Moreover, large collecting vessel from the lymphatic nets passed through the muscular crus of the diaphragm near the medial arcuate ligament and traveled inferior to merge at the original portion of the thoracic duct at the level of the renal vessels. From these observations, the lymphatics on the posterior part of the thoracic surface of the diaphragm communicated with several regional lymphatics independently. This morphological lymphatic traveling suggests that the route differs in cases of pleural effusion or cancer metastasis.

Age-related changes in thyroid lesions and function in F344/DuCrj rats

Age-related thyroid changes, such as those in weight, histology, morphometry, and hormonal concentrations were evaluated in 460 male and 460 female F344 rats from 9 to 109 weeks of age. The absolute weight of the thyroid increased with age in both sexes, but the relative weight was unaffected by age. Ectopic thymus and ultimobranchial cyst were observed in rats of both sexes from 9 to 109 weeks of age. The incidence of both congenital anomalies decreased with age. The incidence of follicular cyst, which was first observed in rats at 20 weeks of age, increased at 109 weeks. Hyperdistention of the follicle with infiltration of macrophages in the lumen and deposition of brown pigments in the cytoplasm of epithelial cells were observed in a few rats at 59 weeks of age. These follicular lesions were found in 29% of the males and 7% of the females at 109 weeks. The first thyroid tumor was seen at 59 weeks of age. In 109-week-old rats, 5% of males had follicular tumors, and 18% of males and 10% of females had C-cell tumors. At 82 weeks of age, the follicular area and the area of the follicular lumen increased, and the height of follicular epithelial cells decreased. Serum T3, T4 and TSH concentrations decreased with age and were significantly reduced at 82 weeks. These results suggest that in F344 male rats the thyroid structural and functional changes occurred with age, and thyroid function decreased after 82 weeks of age.

Development of the human medial superior olivary nucleus: a morphometric study

The development of the human medial superior olivary nucleus was studied in serial sections of 10 fetuses at 12-35 weeks of gestation (WG), an infant at 2 months of age and an adult of 63 years using an electronic planimeter with a computer. Morphometric analysis suggested that the development of the human medial superior olivary nucleus accelerates between 16 and 21 WG in terms of columnar lengths and volumes, neuronal sizes and circularity ratios, while it matures gradually in terms of the amount of Nissl bodies.

A novel method for regenerating plants from mesophyll protoplasts of Arabidopsis thaliana line WS

A procedure has been developed for the successful regeneration of plants from mesophyll protoplasts of Arabidopsis thaliana line WS. The protocol is an improved version of that of Damm and Willmitzer (1988).The main changes in original procedure are as follows: (1) A mixture of Cellulase Y-C (0.5%) and Pectolyase Y-23 (0.05%) is used for the isolation of protoplasts. Use of these enzymes reduces the incubation time to 50 min. (2) α-Naphthaleneacetic acid is used as the auxin throughout cultures of protoplasts and calli. (3) Protoplasts and calli are incubated under dim white light (0.8-8 μW/cm(2)) during culture. With these modifications, we were able consistently to obtain regenerated shoots from about 70% of calli that had been transferred to shoot-forming medium even though the plating efficiency was rather low (about 0.5-1.5%).

Histopathological findings of the digits in dairy cows in Japan

Two hundred and thirty-nine digits of 45 Holstein dairy cows, which were raised in typical Japanese dairy farms and received poor hoof management, were randomly obtained in the slaughterhouses and examined histopathologically. The findings were classified into 5 grades on the basis of the severity of circulatory disturbances and of keratogenesis. The lesions from Grade 1 to 5 were considered as manifestations of serial lesions indicating that subclinical laminitis advanced to other hoof lesions. The incidence of Grade 2, regarded as subclinical laminitis, reached approximately 50% of digits examined. The lesions classified as Grades 3 (23.9%) and 4 (5.4%) were mainly characterized by circulatory disturbances, which were similar to those of chronic laminitis in the previous reports. The incidence of Grade 5, characterized by sole ulcer, was 5.4%. It is suggested that a considerable number of daily cows in Japan suffered from subclinical laminitis, which may be the cause of recent high incidence of hoof diseases in dairy cows.

Apoptosis induced in mouse hepatitis virus-infected cells by a virus-specific CD8+ cytotoxic T-lymphocyte clone

Morphological changes of mouse hepatitis virus-infected J774.1 cells cocultured with cloned mouse hepatitis virus-specific CD8+ cytotoxic T lymphocytes were examined by electron microscopy. Condensation and margination of chromatin, cellular shrinkage with severe vacuolar degeneration, and blebbing were observed. In addition, fragmentation of cellular DNA was observed, and a decrease in virus titer was accompanied by those changes. These findings show that the cloned cytotoxic T lymphocytes induce in the target cell an internal degradation program termed apoptosis, which results in virus clearance.

Partial characterization of larval antigens of Strongyloides papillosus by western blot analysis

Western blotting was used to analyse the antigens in extracts of adult and infective larvae (SIL) of Strongyloides papillosus with serum of infected rabbits. Several proteins in both the extracts reacted with immunoglobulin G in the serum. A protein of about 16 kDa in the extract of SIL showed an especially strong reaction. No cross-reaction was observed among proteins in the extracts of adult worms of such cattle helminths as Fasciola gigantica, Homalogaster paloniae, Trichuris discolor and Setaria digitata to S. papillosus-infected rabbit serum. The cuticle of the worms and substances in the worm tracks showed positive reaction with the immunoperoxidase test on SIL with the serum.

Apoptotic changes in the thymus of mice infected with mouse hepatitis virus, MHV-2

In mice infected with MHV-2, histopathological changes of the thymus was studied. Extensive cell lysis with pyknotic nuclear debris appeared at 48 hr postinfection, and cortico-medullary border was indistinguishable. Electron microscopy revealed vacuolation and shrinkage of the cytoplasm of lymphoid cells, margination of nuclear chromatin, and fragmentation of nuclei. Virus particles were detectable in the lymphoid and reticular epithelial cells, being immunohistochemically positive for viral antigen. By DNA electrophoresis thymocytes showed DNA fragmentation with a laddering pattern characteristic of apoptosis.

A case of intracytoplasmic edema of follicular epithelial cells in rat thyroid

Hydropic change of follicular epithelial cells in the thyroid was observed in a female Fischer 344 rat. Microscopically follicular epithelial cells were characterized by edematous swelling with weakly eosinophilic and homogeneous cytoplasm. The cytoplasm was negative for periodic acid-Schiff reaction, and thyroxine- and thyroglobulin-immunohistochemical reactions. Electron-microscopically, a small amount of amorphous substance was noted in remarkably dilated rough-surfaced endoplasmic reticulum (r-ER), and slight regressive changes of cytoplasmic organella were also observed. These morphological changes may indicate that focal intracytoplasmic edema was occurred in r-ER, and that the change belonged to hydropic degeneration of the thyroid follicular cells in the thyroid.

Identification of sublines of inbred strains of mice and assessment of genetic relationships between substrains or sublines by DNA fingerprinting

Identification of substrains or sublines of inbred mice and assessment of genetic relationships among them were performed on the basis of DNA fingerprinting using M13 phage DNA as a probe. We used eight C57BL/6 sublines (J parallel Jcl, J parallel Jms, J parallel Slc, J parallel Nrs, J parallel Yok, Jah, N parallel Crj, N parallel Jcl) and eleven C3H/He sublines, (J, J parallel Jcl, J parallel Yok, J parallel Nrs, J parallel Jms, N, N parallel Jcl, N parallel Crj, Slc, Jah, Nrs). Two kinds of restriction endonucleases (HinfI and PstI) were used. It was found that: 1) DNA fingerprint within each subline showed identical patterns. 2) Most sublines of C57BL/6 and C3H/He could be identified using DNA fingerprinting with HinfI except between N parallel Crj and Slc, and among J, J parallel Nrs and J parallel Yok in C3H/He. DNA fingerprints with PstI endonucleases showed low polymorphic banding patterns. 3) A dendrogram constructed from DNA fingerprint patterns reflected generally the genealogy of the sublines used. 4) DNA fingerprinting, therefore, seemed to be suitable for the genetic monitoring and assessment of genetic relationships among sublines of inbred mice having close relationships.

Nizofenone, a neuroprotective drug, suppresses glutamate release and lactate accumulation

It was investigated whether nizofenone, 2'-chloro-2-(2-diethylaminomethyl-1- imidazolyl)-5-nitrobenzophenone fumarate, shows neuroprotective effect by inhibiting glutamate release and lactate accumulation in rats. Nizofenone (10 mg/kg i.p.) significantly inhibited neuronal cell death in the hippocampus CA1 pyramidal cells 7 days after 15 min of ischemia caused by 4-vessel occlusion. The extracellular level of glutamate and lactate increased in the hippocampus during ischemia. Upon reperfusion, the glutamate level decreased rapidly but, in contrast, the lactate level increased further and reached a maximum at 15 min following reperfusion. Nizofenone (10 mg/kg i.p.) completely inhibited the ischemic glutamate increase and post-ischemic lactate increase. These results suggest that the inhibition of ischemic release of glutamate and post-ischemic accumulation of lactate could contribute greatly to the neuroprotective effect of nizofenone.

Vascular mineralization in the monkey brain

Mineralization of various degrees was found in the brains of 79 (59%) of 134 cynomolgus monkeys (Macaca fascicularis). There was no age dependency in the incidence or severity, nor were there any abnormalities in growth, weight gain, or neurologic signs, although a slight sex difference was observed. The lesions, which were basophilic and intensely positive for periodic acid-Schiff or von Kossa stain, occurred in the vascular walls of the globus pallidus in two types: globoid bodies with prominent concentric lamellar structures in and around the arteriolar and venular wall (type A) and fine granules in the media of small or medium-sized arteries (type B). Electron microscopic examination revealed dense deposits in the degenerated media of small or medium-sized arteries or the thickened walls of the arterioles. X-ray microanalysis demonstrated the presence of calcium, phosphorus, iron, zinc, magnesium, and aluminum.

Spontaneous vascular mineralization in the brains of cows

The frequency of occurrence and the characteristics of vascular mineralization in the brains of cows were studied. Mineralized lesions were found in the pallidal arteries in eight of 13 cows. They appeared as basophilic deposits in the arterial walls, were sheath-like or tubular in shape, and were accompanied by intimal oedema or fibrous thickening. The deposits were positive for periodic acid-Schiff, von Kossa's, alizarin red and Berlin blue stains. Elemental analysis revealed the presence of large amounts of phosphorus, calcium and zinc, as well as small amounts of iron, copper and sodium.

Relationship between hemolytic activity and adsorption capacity of aluminum hydroxide and calcium phosphate as immunological adjuvants for biologicals

Aluminum hydroxide (Al) and calcium phosphate (Ca) gels have been used as vaccine adjuvants for many years. We investigated mechanism of the hemolytic activities of both adjuvant materials. The hemolytic activity of each gel depended on the gel dose. The adsorption capacities and the hemolytic activities of both adjuvants decreased as the concentration of phosphate increased in a gel-washing solution. A positive correlation between the hemolytic activity and the adsorption capacity was found in Al-gel. A disruptive effect of Ca-gel on membrane of erythrocytes was shown by electron microscopy. Ca-gel required more than 10 times as much pre-adsorbed ovalbumin as did Al-gel to inhibit the hemolysis. These results suggest that the hemolytic activity of both adjuvant materials depended mainly on the adsorption ability, and it may be useful to control the adsorption ability of adjuvants to reduce their hemolytic activity.

Phylogenetic place of a mitochondria-lacking protozoan, Entamoeba histolytica, inferred from amino acid sequences of elongation factor 2'

Partial DNA regions encoding a major part of translation elongation factor 2 (EF-2) from a mitochondria-lacking protozoan, Entamoeba histolytica, were amplified by polymerase chain reaction and their primary structures were analyzed. The deduced amino acid sequence was aligned with other eukaryotic and archaebacterial EF-2's, and the phylogenetic relationships among eukaryotes were inferred by the maximum likelihood (ML) method. The ML analyses using four different stochastic models of amino acid substitutions consistently suggest that among eukaryotic species being analyzed, E. histolytica is likely to have diverged from other higher eukaryotes on the early phase of eukaryotic evolution.

Comparative study of goitrogenic actions of 3-substituted 1, 2, 4-triazoles in rats

Antithyroid actions of 3-amino-1, 2, 4-triazole (ATZ), 3-mercapto-1, 2, 4-triazole (MTZ) and 3-nitro-1, 2, 4-triazole (NTZ), which are substituents on the 3-position of 1, 2, 4-triazole (TZ), and those of the parental compound, were compared in rats. After administration of either ATZ, MTZ, or NTZ, the thyroids of rats were enlarged with decreasing of colloid content and a proliferation of the follicular epithelia. The serum concentration of 3, 5, 3'-triiodothyronine and thyroxine decreased, while that of thyroid-stimulating hormone increased. ATZ, MTZ, and NTZ inhibited thyroid peroxidase activity both in vivo and in vitro. These antithyroid actions were the most remarkable in case of MTZ and were the least in case of NTZ. TZ had no effect on the thyroid function in vivo and in vitro. The results of Lineweaver-Burk analysis on the effect to lactoperoxidase activity indicated that ATZ, MTZ, and NTZ showed competitive inhibition. These results suggest that both MTZ and NTZ have goitrogenic effects on the thyroid through antiperoxidase action, such as ATZ. Thus, the 3rd carbon position of TZ is thought to be important for induction of goiter in rats. A comparison of the relationship between substituent on the 3-position of TZ and antithyroid activity shows that a mercapto moiety has more potent antithyroid action than an amino and a nitro moiety. It is concluded that the differences in antithyroid activity of TZ derivatives depend on the potency of the substituents.

Local pathological reactions induced in pigs and cats by adjuvant ISA-70 containing inactivated Newcastle disease virus antigen

Gross and microscopic changes at the injection site in pigs and cats were investigated for 8 weeks after an intramuscular injection of oil adjuvant ISA-70 emulsion, containing inactivated Newcastle disease virus antigen. In pigs, an egg-sized and discolored lesion with pinpoint to miliary-sized nodules was observed at 2 to 8 weeks post injection (PI). In cats, there was partial thickening of the subcutaneous tissue at 2 to 8 weeks PI. Histopathologic changes in pigs were fundamentally similar to those in cats, however, the local tissue reactions in pigs were severer and more protracted than those in cats. The lesions in pigs were characterized by formation of large-sized cysts and well-developed encapsulation of the cysts with epithelioid cells.

Ulcerative colitis associated with Weber-Christian panniculitis and musculitis: a case report

A case of 22-year-old man suffering from ulcerative colitis, in whom Weber-Christian panniculitis and musculitis occurred simultaneously, is reported. He had suffered from ulcerative colitis for 7 years and he again had bloody stools 1 month before being admitted. Two weeks before admission, large (2-4 cm) subcutaneous tumors appeared. Weber-Christian panniculitis, musculitis, and active stage ulcerative colitis were diagnosed. All the symptoms went into remission after steroid therapy. The possibility of the existence of a common antigen in enterobacterial wall, colonic epithelium, and adipose tissue was suggested.

Necrotizing meningoencephalitis in pug dogs in Japan

This report records necrotizing meningoencephalitis in three pug dogs. It is the first record of the disease in Japan. There were three characteristic histopathological findings, namely (1) a non-suppurative inflammatory cell infiltration of the cerebral hemispheres, including both gray and white matter, (2) meningeal and perivascular infiltrates of mononuclear cells, with a strong tendency to invade the underlying or surrounding brain parenchyma, and (3) selective cerebral cortical necrosis, often occurring without a concurrent inflammatory reaction. The three cases, which were diagnosed as pug dog encephalitis, resembled those previously reported in the United States of America, Switzerland and Italy. All affected animals were females with clinical histories of pregnancy or phantom pregnancy 2 weeks or less before the onset of the clinical signs.

The distribution of amyloid beta precursor protein in canine brain

The distribution of amyloid beta precursor protein (APP) in canine brain was investigated. By immunoblot analysis, APP-positive bands corresponding to proteins of 105-120 kilodalton were recognized in all canine brains regardless of the individual age of the dogs. Bands of similar molecular mass were also detected in the meninges, cerebrospinal fluid, and several visceral organs. Immunohistochemical studies were performed using cryostat and paraffin-embedded sections pretreated with formic acid or by the hydrated autoclave method. In the normal canine brain, APP was found to be distributed in the neurons and vascular system. In the brains with SP, obvious accumulation of APP was observed in swollen neurites within amyloid plaques, although the relationship between APP and diffuse plaques was unclear. APP accumulation in swollen axons was also seen around necrotic foci in the brain of one dog with necrotizing purulent encephalitis. These studies revealed that distribution of APP in canine tissues, especially in the brain, and the accumulation of APP in swollen neurites or axons.

Protein phylogeny gives a robust estimation for early divergences of eukaryotes: phylogenetic place of a mitochondria-lacking protozoan, Giardia lamblia

A partial nucleotide sequence of the mRNA encoding a major part of elongation factor 1 alpha (EF1 alpha) from a mitochondria-lacking protozoan, Giardia lamblia, was reported, and the phylogenetic relationship among lower eukaryotes was inferred by the maximum-likelihood and maximum-parsimony methods of protein phylogeny. Both the methods consistently demonstrated that, G. lamblia among the four protozoan species being analyzed, is the earliest offshoot of the eukaryotic tree. Although the Giardia EF1 alpha gene showed an extremely high G+C content as compared with those of other protozoa, it was concentrated only at the third codon positions, resulting in no remarkable differences of amino acid frequencies vis-à-vis those of other species. This clearly suggests (a) that the amino acid frequencies of conservative proteins are free from the drastic bias of genome G+C content, which is a serious problem in the widely used tree of ribosomal RNA, and (b) that protein phylogeny gives a robust estimation for the early divergences in the evolution of eukaryotes.

Development of the human gigantocellular reticular nucleus: a morphometric study

The cytoarchitectonic development of the human gigantocellular reticular nucleus (GRN) was studied quantitatively in 15 fetuses (16-39 weeks of gestation: WG) and in 2 adults (16 and 85 years old). With microscopic observation on serial celloidin sections of the brain, we measured them to obtain the following morphometric parameters: numerical density (ND), profile area (PA), and perimeter (PL) of the GRN neurons. GRN appeared as early as early as 16-18 WG, but most neurons were still immature and the cell nucleus was relatively large (nucleocytoplasmic ratio was high), although a few large neurons containing fine Nissl bodies were observed. Typical, coarse Nissl bodies of large multipolar neurons were first recognized at 21 WG. The earliest myelination was noticed at 22-23 WG, but myelinated nerve fibers were not prominent until the late fetal period. ND was largest at 16 WG and decreased rapidly with gestational age (coefficient of correlation, r = -0.85): it was reduced to about 10% of that at 16 WG by the end of the fetal period. ND was smaller in the adults than in the fetuses. Average PA increased monotonously with gestational age (r = 0.79). The coefficient of variation (CV) of PA was high early in the fetal period (47-48%; 16-18 WG) and increased gradually with age (r = 0.40). The average circulatory ratio (CR = 4 pi PA/PL2) decreased monotonously with gestational age (r = -0.85), while the CV of CR increased (r = 0.76). In conclusion, this study suggests that immature GRN neurons may appear by 16 WG after migration and that the subsequent differentiation and maturation may progress gradually and monotonously during the later half of gestation.

Hemolytic toxin produced by Porphyromonas gingivalis

Porphyromonas gingivalis no. 381 and ATCC 33277 produced an extracellular hemolytic toxin which was heat-labile, trypsin-sensitive, and lytic to human, horse, sheep and rabbit erythrocytes. The hemolytic toxin is a 'hot-cold', thiol-independent toxin. The production of the hemolytic toxin was greatly enhanced by addition of hemoglobin to the culture medium.

Computed tomography and magnetic resonance findings of meningeal syndrome in a leukemic cat

A 3-year-old Japanese domestic cat with a diagnosis of lymphocytic leukemia showed severe generalized seizures in the course of chemotherapy after leukemic condition was improved clinically. Computed tomography (CT) and magnetic resonance (MR) imaging of the brain were carried out. Both contrast procedures disclosed enhancements at the falx cerebri and the margin of cerebral cortex. Among these procedures contrast MR imaging demonstrated the lesion most clearly. Cytological examination of cerebrospinal fluid obtained by spinal puncture showed the infiltration of malignant cells and the diagnosis of meningeal syndrome associated with lymphocytic leukemia was defined. Intrathecal administration of cytosine arabinoside partially improved the neurologic dysfunction. Autopsy and histopathological examination confirmed the infiltration of leukemic cells in the areas of meningeal lesion demonstrated with contrast CT and MR imaging. Thus these imaging techniques, especially contrast MR imaging, are useful tools for rapid and precise diagnosis of meningeal syndrome.

Use of body fluid of adult female Ascaris suum as an antigen in the enzyme-linked immunosorbent assay (ELISA) for diagnosis of swine ascariosis

The Enzyme-linked immunosorbent assay (ELISA) was used to detect Ascaris suum antibodies in swine sera with adult body fluid (ABF) as an antigen. The assay was standardized with respect to the antigen concentration and serum and conjugate dilutions. Cross reaction was found between the antigen and the sera from the swine infected with Metastrongylus apri. The ELISA was more sensitive than the complement fixation test. Five protein peaks were obtained from ABF by gel filtration on Sephacryle S-300. Fraction 1 was the most specific. A 105 kDa protein in the fraction reacted with swine IgG in the serum of infected animals in Western blot analysis.

Malignant histiocytosis with multiple skin lesions in a dog

A 7-year-old male Yorkshire terrier was examined for multiple plaques and nodules on the skin. The clinical, cytological and histopathological features indicated a malignant histiocytosis. Cytoreductive chemotherapy produced moderate clinical improvement, but died at day 90 after the first admission. Pathological examination revealed the neoplastic histiocytes in the skin as well as in the myocardium and skeletal muscles.

Spontaneous globoid mineralization in the cerebellum of rats

Cerebellar globoid mineralization in two rats was examined by light and electron microscopy, and by X-ray microanalysis. The mineralization was round to oval in shape; it varied in size and was positive for the periodic acid-Schiff and von Kossa reactions. Ultrastructurally, a concentric lamellar structure was prominent in moderately electron-dense depositions. Elemental analysis revealed the presence of large amounts of calcium and phosphorus, and small amounts of zinc, potassium and aluminum.

Campylobacter showae sp. nov., isolated from the human oral cavity

Nine Campylobacter-like strains were isolated from human gingival crevices and characterized. These strains were gram-negative, straight rods that were motile by means of multiple unipolar flagella. They were asaccharolytic and preferred an anaerobic atmosphere rather than a microaerophilic atmosphere for growth, and their growth was stimulated by formate and fumarate. These strains were biochemically similar to Campylobacter curvus and Campylobacter rectus, but were clearly distinguishable from these organisms by the number of flagella (two to five flagella at one end of the cell), by being catalase positive, by their whole-cell protein profiles, by their Western blot (immunoblot) patterns, and on the basis of DNA-DNA homology data. They could also be differentiated from the other species of the genus Campylobacter. The nine Campylobacter-like strains were compared with two strains (FDC 286 and VPI 10279) representing a previously described but unnamed Wolinella sp. The nine isolates and strains FDC 286 and VPI 10279 were found to be members of a single species. The 16S rRNA sequences of two strains of the newly identified species were compared with the rRNA sequences of 21 reference Campylobacter, Wolinella, and Helicobacter species in order to generate a phylogenetic tree. We propose the name Campylobacter showae for the newly identified strains; strain SU A4 (= ATCC 51146) is the type strain of this new species.

Systemic ceroid-lipofuscinosis in a Japanese domestic cat

An 11-month-old castrated male Japanese domestic cat was euthanized because of neurological symptoms such as shivering and difficulty of walking. Histopathological examination showed glial proliferation and marked deposition of ceroid-lipofuscin in the neuronal and glial cells of the brain. Ceroid-lipofuscin was deposited also in reticuloendothelial cells of the liver, spleen and some lymph nodes.

Double-labeling immunohistochemical studies on canine senile plaques and cerebral amyloid angiopathy

The relationship of senile plaques to neuronal cells, neurites, glial cells, or capillaries was examined using double labeling-immunostaining methods on the Bouin's solution-fixed serial brain sections from dogs. Compact deposits of beta protein (amyloid plaques) in the cerebral cortex always contained microvessels labeled by anti-collagen type IV antibody and some of them might be formed as the result of fusion of several perivascular beta amyloid deposits. In the periphery of those plaques swollen neurites recognized with anti-neurofilament antibody were sometimes present, but the relation between such plaques and neuronal cells or glial cells were unclear. Diffuse deposition of beta protein (diffuse plaques) was frequently developed beside neuronal cells, while most plaques did not contain glial cells. Some of those plaques were closely contact with microvessels, but some had no relation. Intact or irregularly arranged neurites were present in diffuse plaques. Such irregularity of the neurites were obvious in the plaques in the hippocampus as compared with those in the cerebral cortex. These results indicate the possibility that canine amyloid plaques would be formed as the result of amyloid degeneration of cortical capillaries, and diffuse parenchymal deposition of beta protein would originate from neuronal or neuritic processes.

Effects of hepatic enzyme inducers and mitogens on experimental Tyzzer's disease in rats

We studied the effects of chemicals which induce liver enlargement and can induce hepatic protein synthesis on experimental Tyzzer's disease in rats. Plasma transaminase values were evaluated as an indicator of the severity of the disease. Chemicals used were phenobarbital sodium and 3-methylcholanthrene as hepatic enzyme inducers, and lead nitrate and ethylene dibromide as mitogens of hepatocytes. In rats non infected with Tyzzer's organism, liver weight in those treated with these chemicals was higher than that in rats without chemical treatment. Tyzzer's disease-infected rats treated with these chemicals showed higher plasma transaminase values and more severe histopathologic liver lesions than infected rats without chemical treatment. The results indicated that the growth of Tyzzer's organisms in hepatocytes was accelerated in the course of hepatocytic metabolic changes during liver enlargement, and that protein synthesized in the hepatocyte may play an important role in the nutritive requirements of the organism.

Collagen production and maturation at the experimental ligament defect stimulated by pulsing electromagnetic fields in rabbits

Eighty rabbits receiving the square resection (4 x 4 mm) of both patellar ligaments in full thickness at their center were divided into 4 groups, and each group (20 rabbits) were electromagnetically stimulated with different magnetic intensities, 0 (control group), 2, 10, or 50 gauss (G), for 6 hr daily. Pulse frequency and pulse width were 10 Hz and 25 microseconds, respectively. Five animals of each group were sacrificed weekly from 1st to 4th week after operation and the defect tissue was collected for biochemical and ultrastructural evaluations. Before sacrificing, the blood flow of the central portion of patellar defects were measured. Significant increases in blood flow at the defect were observed in 50 G group compared to those of other groups from 2 to 4 weeks after operation. The collagen content in PEMFs groups showed a significant increase compared to that of control group. Furthermore, those increases were higher according to the increase in magnetic intensity. Electronmicroscopically, massive developmental rough endoplasmic reticulum was seen in the fibroblasts at 2 weeks after operation in 50 G group compared to other groups, which suggests the more active collagen production in this group. These results suggest that PEMFs enhanced the blood flow and increased the fibroblasts at the defect. At the same time, PEMFs directly stimulated the collagen production from the fibroblasts, thus accelerate the healing process of the ligament.

[Application of DNA fingerprinting to investigation of genetic relationships between laboratory rabbit strains]

It is well known that laboratory rabbits are not controlled genetically like laboratory mice and rats. In order to test the usefulness of DNA fingerprinting in investigation of genetic uniformity of the laboratory rabbits strains and their relationships, we applied DNA fingerprinting using bacteriophage M13 probe to five strains (2 inbreds (JWY-NIBS and DuY-NIBS) and 3 outbreds (JW-NIBS, Icl:JW and WHHL)). DNA fingerprints of 2 inbred strains showed the same banding patterns within each strain but the strain-specific patterns. Although there were no rabbits showing the same banding patterns in 3 outbred strains, average percent differences (APD) were 13.7 to 18.6. A dendrogram based on APD of DNA fingerprints was constructed by 2 large clusters, JW group and DuY. The dendrogram was essentially similar to that based on rabbit mandible measurements. These results suggest that DNA fingerprinting is available not only for the genetic monitoring of the laboratory rabbit strains but also for the investigation of their genetic relationships.

[Relative growth of physiques in laboratory-bred cynomolgus monkeys: a longitudinal study during the first 6 years of life]

Physical growth was studied longitudinally in laboratory-bred cynomolgus monkeys (Macaca fascicularis) aged from birth to 6.0 years in females and to 6.5 years in males. An allometric formula was applied to morphometrical growth data and the relative growth of each morphological site to anterior trunk length was analyzed. The growth patterns of all of the measurement sites in females and most of the sites in males showed monophasic allometry; while those of head length, head breadth and morphological upper face length in males were judged to show diphasic allometry. The growth patterns of morphological total face length, upper arm length and lower arm length in some males showed diphasic allometry. Morphological measurements with negative allometry were head length, head breadth, morphological total face length, total head height, biacrominal breadth hand length and foot length, while the other morphological measurements revealed isometry in both sexes. However, the values of the relative growth coefficient to anterior trunk length were larger in males than in females, except for in the case of biiliac breadth. These differences in growth patterns may cause the morphological differences between genders after sexual maturation in this primate species.

[An autopsy case of brain candidiasis in premature infant: morphology and intraparenchymal distribution of Candida foci]

An autopsy case of brain candidiasis occurring in a premature infant is presented, and the morphology and intraparenchymal distribution of Candida foci are described in detail with the aid of serial sections of the affected brain. The patient was a boy, who was born after 25 weeks of gestation and died on day 15. Candida foci were composed of two infectious forms of Candida (yeasts and pseudohyphae) and various inflammatory reactions of the host. They were widely disseminated in the brain parenchyma, leptomeninges and ventricular system. In view of their morphology, they were classified into the acute and chronic inflammatory types. The acute type foci, characterized by microabscess of infiltration of neutrophils, were large and localized predominantly in the cerebral white matter, fiber tracts, central grey matter of the midbrain, reticular formation, floor of fourth ventricle and subependymal germinal layer; most of the acute type foci were found in the watershed zones where the blood supply was considered to be poorer than the other parts of the brain parenchyma. In contrast, the chronic type foci, characterized by nodular proliferation of astrocytes, were small and localized in the grey matter (the cerebral cortex, basal ganglia and brainstem nuclei) and the leptomeninges. This study suggests that Candida infection to the brain may occur by different two kinds of way correlating with the proper vasoarchitecture of brain. In addition, it is recommended to make a close examination of the maternal vagina, placenta and umbilical cord after delivery to detect the risk of Candida infection.

Establishment of inbred strain of long-haired golden hamster

Features of a long-haired mutant and inheritance of mutation were investigated in the golden hamster (Mesocricetus auratus). The hair of adult long-haired hamsters was longest at the rump and flanks (approximately 70 mm) and was also unusually long at the neck (45 to 50mm). The hair length of males was more striking than that of females. Mating experiments indicated that an autosomal recessive gene is responsible for the inheritance of long hair. An albino long-haired hamster strain was established by continuous full-sib mating from F2 hybrids, descendants of (acromelanic albino x agouti long-haired) F1 progeny, and genetic homogeneity was confirmed by DNA fingerprinting. The long-haired strain was characterised by the fact that males grew larger than females, in contrast to the other strains of hamsters.

Genetic similarity using DNA fingerprinting in cattle to determine relationship coefficient

The relation between relationship coefficient and genetic similarity was evaluated using DNA fingerprinting in Japanese Black cattle. We proposed a new method for evaluating heterozygous and homozygous minisatellite loci. Genetic similarity by DNA fingerprinting was estimated by two methods--band sharing (BS) and a new evaluation called genetic similarity (GS). Linear regressions of the relationship coefficient (y) on levels of BS (x1) and GS (x2) yielded the equations y = 0.049 + 0.684x1 and y = -0.206 + 1.149x2, with highly significant correlation coefficients of .631 and .813, respectively. It was suggested that DNA fingerprinting could be applied to estimate the relationship coefficient not only in cattle but also in other species.

Influence of chronic oestrogen treatment on severity of hydronephrosis in inbred DDD mice

It has been reported that mice treated chronically with oestrogen (oestradiol propionate) increase their bladder urine volume. Since inbred DDD mice, particularly male DDD mice, lack a protective mechanism against vesicoureteral reflux (VUR), chronic oestrogen treatment may increase the pressure in the renal pelvis and lead to severe hydronephrosis. The present studies were carried out to confirm this hypothesis. Results of a least-squares analysis of variance showed that the severity of hydronephrosis was more severe after treatment with high doses of oestrogen (1.0 and 5.0 mg/kg/week) in entire and castrated male DDD mice. Hydroureter was also observed in the same groups. Intra-vesicular pressure was 7 to 12 cmH2O higher in mice of these groups than in control DDD mice. High doses of oestrogen had no effect on the kidneys of C57BL/6 mice which showed normal protection against VUR, though it increased bladder urine volume. These findings support the hypothesis that hydronephrosis in DDD mice is caused by an incomplete protective mechanism against VUR.