Variation in serum creatine phosphokinase activity as indicated in two-phase EMC-D virus-induced myocarditis

In this study, myocardial damage in the D-variant of encephalomyocarditis (EMC-D) virus-induced myocarditis has been investigated consecutively by measuring serum creatine phosphokinase (CPK) activity. CPK activity in 8 week-old male BALB/cAJcl mice inoculated with EMC-D virus increased to a peak at 4 or 5 days postinoculation (DPI) and then gradually decreased. The CPK activity rose again after 7 DPI until it reached a second peak. In view of the kinetics of CPK activity, two-phase (early and late phase) myocardial damage in EMC virus infection were considered. In the late phase, an increase in cellular infiltration in the myocardium and a decrease in viral titer in the heart were observed. It was therefore suspected that the increase in CPK in the late phase may be caused by cellular infiltration, but not by viral replication. In our results, we suggested that a serial measurement of serum CPK activity might be a useful method for throwing more light on the myocardial damage caused by the autoimmune response. We also used a pathological (TUNEL) method to detect apoptotic cells and some apoptotic myocytes in the myocardium in late phase EMC virus-induced myocarditis.

Myocyte remodeling during the progression to failure in rats with hypertension

Regional changes in cardiac myocyte shape during the progression to failure with hypertension have not been clearly established. To address this issue, we examined left and right ventricular myocytes from lean, female spontaneously hypertensive/heart failure rats with compensated hypertrophy (approximately 12 months of age) and congestive heart failure (approximately 24 months of age). During this period, body weight did not change, but heart weight increased 59% and lung weight increased 93%. Left ventricular function declined with the onset of failure. Left ventricular myocyte volume increased 27% exclusively because of myocyte lengthening (29% increase). The onset of left ventricular failure resulted in a 72% increase in right ventricular myocyte volume. Right ventricular myocyte growth, however, was proportional, with a 23% increase in myocyte length and 18% increase in myocyte width. Changes in left ventricular myocyte shape were virtually identical to data collected previously from patients with similar disease, suggesting that this is a relevant animal model. Evidence suggests that left ventricular myocyte transverse growth is defective because dilation and failure were associated with cell lengthening, without a change in myocyte diameter. Although severe hypertrophy was present in the right ventricle as a result of left ventricular failure, myocyte growth was proportional, suggesting that cell shape was properly regulated in this chamber.

Activation of canine monocytes and polymorphonuclear cells by serum thymic factor (FTS) in vivo

The effect of serum thymic factor (FTS) was evaluated from the immunoresponse augmented in canine monocytes and polymorphonuclear cells (PMN) using the chemiluminescence technique. FTS did not affect the number of leukocytes and differential count of leukocytes. CL activity of the whole blood was significantly elevated by FTS from 72 hr to 120 hr after administration (p < 0.05), and that at 96 hr after administration was about 3-fold higher than that before the administration. The CL response of PMN was significantly elevated by FTS administration from 24 hr to 96 hr after administration (p < 0.05), and that at 48 hr after administration was about 7-fold higher than prior treatment. FTS also significantly elevated the CL response of monocyte from 24 hr to 96 hr after administration (p < 0.01), and the CL count of monocyte in 24 hr and 48 hr was about 100-fold higher than that before FTS administration. These findings suggested that FTS may be efficacious and useful immuno-potentiator for canine monocytes and PMN.

Production and characterization of polyclonal anti-canine interleukin-8 antibodies

Polyclonal anti-canine interleukin-8 (cIL-8) antibodies were raised in rabbits immunized with cIL-8 expressed by E. coli. Polyclonal antibodies were purified by affinity chromatography. In the enzyme linked immunosorbent assay (ELISA), the resulting anti- cIL-8 antibodies showed relatively high reactivities with cIL-8 in the fusion proteins of glutathione-S-transferase/cIL-8 (GST/cIL-8) and maltose binding protein/cIL-8 (MBP/cIL-8), but negligible ones with MBP. Furthermore, Western blotting analysis using these polyclonal antibodies showed distinct bands for cIL-8, GST/cIL-8, and MBP/cIL-8. These antibodies also bound to recombinant human IL-8 (rhIL-8) in ELISA but not in Western immunoblotting. The rHIL-8 (50-800 ng/ml) was chemoattractant for canine neutrophils in a dose dependent manner, but the anti-cIL-8 antibodies did not show the inhibitory effect on the chemotactic activity of rhIL-8 of canine neutrophils, when tested by the chemotaxis assay using Boyden chambers. In addition, GST/cIL-8 and rhIL-8 induced strong and rapid shape change responses of canine neutrophils. However, the anti-cIL-8 antibodies inhibited shape change responses induced by GST/cIL-8 but not by rhIL-8.

Identification of a promoter region in the rat prion protein gene

We have demonstrated the presence of a rat prion protein (RaPrP) gene promoter upstream of multiple initiation sites. A 0.1-kb fragment upstream of the 5'-untranslated region contains specific DNA motifs characteristic of promoter elements including an AP-1 binding site, an inverted CCAAT motif and three inverted Sp-1 binding sites. This fragment directs transcription of a luciferase reporter gene in pheochromocytoma cells (PC12) and rat glioma cells (C6), suggesting that it contains the promoter for the RaPrP gene. To more precisely localize the transcription regulatory elements in this region, a series of 5'-deletion mutants were generated. Deletion analysis showed that an inverted CCAAt and adjoining Sp-1 binding sequences may play an important role in transcription of the RaPrP gene.

In vivo administration of serum thymic factor (FTS) prevents EMC-D virus-induced diabetes and myocarditis in BALB/cAJcl mice

The effect of serum thymic factor (FTS) on the D-variant of encephalomyocarditis (EMC-D) virus-induced diabetes and myocarditis in BALB/cAJcl mice was investigated. Mice pretreated with 50 or 10 micrograms of FTS were infected with 10 or 10(3) PFU of EMC-D virus. In the mice inoculated with 10 PFU of virus, 40% developed diabetes on post-infection day (PID) 14, whereas those treated with FTS (50 micrograms/administration) on day 2 and 1 before infection did not develop diabetes. FTS (10 micrograms)-pretreated mice developed diabetes. In histological observation, FTS non-treated mice which developed diabetes showed severe necrosis and inflammation of mononuclear cells in the islets of Langerhans and myocardia on 19 PID. Mice pretreated with 50 micrograms of FTS, however, manifested mild islet degeneration without any myocardial inflammation. Furthermore, in FTS non-treated mice, immunohistological staining showed a loss of insulin granules. This loss was markedly reversed and insulin granules remained largely intact in FTS-pretreated mice. Viral titers in pancreas of FTS-pretreated mice approximated well to those of non-treated mice on PID 4, 7 and 19. In mice inoculated with higher titer of EMC-D virus (10(3) PFU), however, 50 micrograms of FTS pretreatment did not change the course of these acute pathological developments (diabetes and myocarditis observed from PID 4).

Three-exon structure of the gene encoding the rat prion protein and its expression in tissues

The prion protein (PrP), encoded by a chromosomal gene, is associated with development of the neurodegeneration of prion-induced diseases. Since determination of the complete structure of the gene encoding PrP is important for understanding gene expression in the central nervous system (CNS), the nucleotide (nt) sequence of the isolated whole gene encoding rat PrP (raPrP) was determined. The rat PrP gene (raPrP) spans 16 kilobases (kb) of the rat genome and contains three exons of 19-47 base pairs (bp), 98 bp, and 2 kb separated by two introns of 2.2 kb and 11 kb. The first and second exons are noncoding, while the third exon contains a short 5' untranslated region, the entire 762-bp open reading frame (ORF), and a 3' untranslated region. The putative raPrP promoter in the 5' flanking region contains putative Sp1, AP-1, and AP-2 binding sites without a consensus TATA box. This TATA box-deficient feature, coupled with the presence of a high G+C content and Sp1-binding sites in the raPrP promoter, characterizes it as a housekeeping gene. Analysis of the raPrP cDNA 5'-end showed that raPrP mRNA transcription was initiated at multiple sites. Northern blot analysis showed that the levels of raPrP mRNA varied among rat tissues, with the highest levels found in the brain and placenta. This determination of raPrP nt sequences, including the introns and the 5' and 3' flanking regions, may make it possible to elucidate cis-acting elements that regulate the expression of this gene in different tissues and cell lines.

Prevention of reovirus type 2-induced diabetes-like syndrome in DBA/1 suckling mice by treatment with antibodies against intercellular adhesion molecule-1 and lymphocyte function-associated antigen-1

Reovirus type 2-induced diabetes-like syndrome in suckling mice is considered to be an animal model for human insulin-dependent diabetes mellitus. We have previously demonstrated that immunopathologic pancreatic islet cell damage might be relevant to reovirus type 2 infection. In this study the involvement of adhesion molecules in the development of reovirus type 2-induced diabetes-like syndrome was examined. In infected mice infiltration of mononuclear cells mixed with polymorphonuclear leucocytes in and around pancreatic islets (insulitis) was observed in association with abnormal glucose tolerance. The treatment with monoclonal antibodies against intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) prevented the development of insulitis with abnormal glucose tolerance in a dose dependent manner. These results suggest that ICAM-1 and LFA-1 molecules may, at least in part, participate in islet cell damage, resulting in reovirus type 2-induced diabetes-like syndrome. The role of ICAM-1 and LFA-1 molecules on the development of insulitis is discussed.

[Toxicity of iodixanol, a new nonionic iso-osmolar contrast medium, to cynomolgus monkeys by repeated intravenous administration for 4 weeks with a 4-week recovery period]

Groups of 3 male and 3 female wild-caught cynomolgus monkeys were given iodixanol, a radiographic contrast medium, by intravenous injection at dosage levels of 100, 300 or 1,000 mgI/kg/day for four weeks to evaluate its toxicity. An extra 2 animals of each sex were given 1,000 mgI/kg/day for 4 weeks and then retained for 4 weeks without treatment to assess recovery. There were no deaths during the treatment period. Bruising at the injection sites was noted clinically and macroscopically was caused in part by the injection procedure itself and in part by the viscosity of the test formulation and the size of the dose. This finding is therefore, of no toxicological significance. No effects of treatment with iodixanol on body weights, food consumption, laboratory investigations, ophthalmoscopic examinations, organ weights or bone myelograms were noted. Cytoplasmic vacuolation of the kidney proximal tubules was noted with incidence and severity increasing with dosage level among animals given 100, 300 or 1,000 mgI/kg/day. This effect was noted not to be fully reversible at 1,000 mgI/kg/day after 4 weeks off-dose although reduced severity was noted and recovery was apparent in some animals.

Enhancing effects of chicken egg white derivatives on the phagocytic response in the dog

Immunostimulative effects of chicken egg white derivatives (EWD) on phagocytic responses of peripheral blood mononuclear cells (MNC) and polymorphonuclear cells (PMN) in dogs were evaluated by flow cytometric analysis. Peripheral blood leukocytes (PBL) cultured with EWD showed the enhanced phagocytic response. The response was maximal when PBL were cultured with 100 - 400 micrograms/ml of EWD for 3 - 12 hr. Furthermore, significantly increased phagocytic responses were also induced even when PBL were cultured with protein components (200 micrograms/ml) of EWD such as conalbumin, flavoprotein and ficin-papain inhibitor for 3 hr. In addition, the enhancing effect of EWD on the phagocytic responses was also observed in MNC cultured with EWD (200 micrograms/ml) for 4 hr but not in PMN cultured with EWD in the same procedures. The supplement of the supernatant (20%) of MNC cultured with EWD (200 micrograms/ml) for 24 hr at 37 degrees C to PBL and MNC resulted in the enhancement of their phagocytic responses. In contrast, the supernatant of PMN cultured with EWD for 24 hr at 37 degrees C did not show any significant enhancing effect on the phagocytic responses of PBL, MNC and PMN. These results suggest that EWD has an enhancing effect on phagocytosis of MNC and PMN, which may be mediated through active humoral substances produced by EWD-stimulated MNC.

[Toxicity of iodixanol, a new nonionic iso-osmolar contrast medium, to rats by repeated intravenous administration for 4 weeks with a 4-week recovery period]

Groups of 10 male and 10 female Crl: CD (SD) BR rats were given iodixanol, a radiographic contrast medium, by intravenous injection at dosage levels of 30, 100 or 300 mgI/kg/day for four weeks to evaluate its toxicity. An extra 5 rats of each sex were given 300 mgI/kg/day for 4 weeks and then retained for 4 weeks without treatment to assess recovery. No clinical signs indicative of a toxic effect of iodixanol were noted. No effects of treatment with iodixanol on bodyweight gains, food consumption, laboratory investigations, ophthalmoscopic examinations, organ weights, bone marrow smears or macroscopic pathology were noted. Treatment related changes were noted microscopically in the kidneys only. Minimal cytoplasmic vacuolation in the proximal tubules was noted in a proportion of rats given 100 mgI/kg/day and all rats given 300 mgI/kg/day at the end of the treatment period. This effect was noted not to be fully reversible during four weeks off dose although recovery did occur in some rats.

Establishment of a bovine macrophage cell line from a fetal thymus

A cell line, FBM-17, was established from a fetal bovine thymus and passaged for more than a year. Electron microscopic examination revealed that the cytoplasm contained many phagosomes and a significant amount of rough endoplasmic reticula. In addition, FBM-17 cells showed non-specific esterase, phagocytosis and surface expression of Fc receptors for IgG and classes I and II MHC antigens. These observations confirmed that this cell line had the morphologic and functional features as a macrophage. MHC expression markedly increased by treatment with recombinant bovine gamma-interferon, showing the cell line to be sensitive to bovine gamma-interferon and functional. These present results suggest that the FBM-17 is a functional bovine macrophage cell line. This line gamma-interferon, showing the cell line to be useful for clarification of roles of macrophages in immunoregulation in cattle.

Detection of the chemotactic factor for canine peripheral blood mononuclear cells and polymorphonuclear cells in the culture supernatant of Cos7 cells transfected with canine interleukin-8 cDNA

Chemotactic activities in the culture supernatants of Cos7 cells transfected with a cloned canine IL-8 cDNA (pcIL-8SR alpha 14) were evaluated by using mononuclear cells (MNC) and polymorphonuclear cells (PMN) from the peripheral blood of dogs. The culture supernatants of Cos7 cells were collected 66 hr after the transfection of pcIL-8SR alpha 14 (Cos7/cIL-8). Chemotactic activities in the culture supernatants for MNC and PMN were determined as migration distances in Millipore membrane filters in a modified Boyden's chamber method. Peroxidase staining for MNC was effective not only for cells in cytospun smears but also for cells migrated in the filters. PMN in cytospun smears were well stained by peroxidase staining, whereas migrated PMN in the filters were stained weakly. Chemotactic activities in the culture supernatant of Cos7/cIL-8 cells for both MNC and PMN were significantly higher than those of control Cos7 cells. In addition, the culture supernatant of Cos7/cIL-8 cells was chemotactic for peroxidase negative nonadherent MNC (lymphocytes), but not for peroxidase positive adherent MNC (monocytes). This Cos7/cIL-8 supernatant also showed chemotactic activities for neutrophils in a dose dependent manner. These results suggest that the culture supernatant of Cos7/cIL-8 is chemotactic for lymphocytes as well as for neutrophils.

[Quality of life in patients with advanced gastric cancer receiving AO-90, a methionine-free intravenous amino acid solution, with 5-fluorouracil and mitomycin C]

We conducted a randomized, multicenter, controlled trial of AO-90, a methionine-free 7.43% intravenous amino acid solution, in patients with advanced recurrent gastric cancer. The regimen used in the study was comprised of two-week treatment cycles, with a withdrawal period between cycles. During treatment, patients were given either AO-90 (500-750 ml/day; AO/MF group) or a commercial amino acid solution (600-800 ml/day; C/MF group) by total parenteral nutrition (TPN) for 14 days concomitantly with MF therapy (5-fluorouracil 350 mg/m2/day, iv continuously for 14 days and mitomycin C 7 mg/m2, iv push on days 7 and 14). We interviewed 118 eligible and evaluable patients (72 men and 46 women; 59 cases in the AO/MF group and 59 in the C/MF group) about their quality of life immediately before the start of treatment, one week and two weeks after the start of treatment, and one week and two weeks after treatment. A 11-item questionnaire was used to interview the subjects: nine questions using a five-point scale, one question using a 100-mm linear visual analog scale, and one question using a five-grade face scale. Changes in the grades compared with baseline data were scored as 1 point (improvement of one grade or more, or 20 mm or more), 0 points (no changes), and-1 point (decline of one grade or more, or 20 mm or more). Before analyzing the significance, quality of life score data were adjusted by the Mantel-Haenszel method due to uneven distribution of subjects concerning baseline performance status and complications. Among the items questioned, subjects receiving AO-90 showed significantly higher scores in appetite, nausea, and ambulation at some evaluation time points than those receiving a methionine-containing TPN. The results show that AO-90 improved the quality of life of patients with advanced recurrent gastric cancer.

[A controlled study of AO-90, a methionine-free intravenous amino acid solution, in combination with 5-fluorouracil and mitomycin C in advanced gastric cancer patients (surgery group evaluation)]

The results of recent preclinical and clinical studies suggest that AO-90, a methionine-free intravenous amino acid solution (7.43%), potentiates the antitumor effect of 5-fluorouracil (5-FU). In the present multi-center, randomized, controlled study conducted at the surgery departments of 53 institutions between July 1991 and March 1993, patients with advanced gastric cancer were randomly allocated to receive either AO-90 (500-750 mL/day, AO/MF group) or Amiparen, a commercial intravenous amino acid solution (600-800 mL/day, C/MF group) by total parenteral nutrition for 14 days. Both groups received MF therapy which consisted of a continuous infusion of 5-FU at 350 mg/m2/day for 14 days and an i.v. push of mitomycin C 7 mg/m2 on days 7 and 14 (one course). Additional treatment courses were initiated after a withdrawal period when appropriate. Of the 138 subjects enrolled, 129 (93.5%) were eligible and 119 (86.2%) completed the scheduled treatment (AO/MF group: 57, C/MF group: 62). The overall clinical response rates in the completed cases were 26.3% (15/57) in the AO/MF group and 8.1% (5/62) in the C/MF group, and the difference between the groups was significant (p = 0.015). In particular, the response rate in the postoperative recurrent patients with measurable lesions was 42.9% (12/28) in the AO/MF group versus 12.0% (3/25) in the C/MF group (p = 0.016). Further, in the patients who were previously treated with fluoropyrimidine drugs, 29.0% (9/31) responded to the AO/MF therapy versus 8.6% (3/35) in the C/MF group (p = 0.053). The treatment-related adverse reactions observed were mainly hematologic and subjective/objective symptoms, such as decreased leukocyte count and hemoglobin level, nausea/vomiting and stomatitis. The differences in the incidence were not significant between the groups. Based on these results, AO-90 in the MF regimen appears to be effective in the treatment of patients with advanced gastric cancer by significantly potentiating the effects of 5-FU.

Cholecystokinin does not act on the efferent pathway of cholinergic and adrenergic nerves to inhibit ruminal contractions in sheep (Ovis aries)

The effect of exogenous cholecystokinin-octapeptide (CCK-8) on ruminal contractions and the role of efferent pathways of cholinergic and adrenergic nerves on the effect were studied in sheep. Intravenous infusion of CCK-8 at 11.4 and 45.6 pmol/kg/min significantly inhibited the frequency and amplitude of ruminal contractions in conscious sheep. After bilateral cervical vagotomy, intravenous infusion of CCK-8 at 45.6 mol/kg/min had no detectable effect on amplitude of ruminal contractions induced by electric stimulation to the cervical vagus nerve (1 msec, 20 Hz, 5 mA, for 10 sec at 1-min intervals) in anesthetized sheep. The amplitude of contractile responses of ovine ruminal muscle strips to acetylcholine at 5 x 10(-5) M was not inhibited by CCK-8 applied simultaneously at 1 x 10(-9) M. Intravenous infusion of phentolamine at 53.0 nmol/kg/min, propranolol at 101.4 nmol/kg/min, or their combined infusion did not alter the inhibitory action of CCK-8 at either dose on ruminal contractions in conscious sheep. These results suggest that CCK-8, which does not act on the efferent pathway of cholinergic and adrenergic nerves, may reflexively inhibit reticuloruminal contractions via vagal afferent fibers in sheep.

Analysis of PrPc mRNA by in situ hybridization in brain, placenta, uterus and testis of rats

An amyloid-like isoform of a 33- to 34-kD glycoprotein, termed as the scrapie prion protein (PrPsc), plays a critical role in transmissible spongiform encephalopathies of animals and humans. It has even been suggested to present the responsible infectious agent. This protein is a posttranslationally modified form of the cellular isoform of prion protein (PrPc). Hitherto, little has been known about the functions of PrPc. In order to examine the localization of PrPc mRNA in rat tissues, the in situ hybridization technique was performed. In rat brain, PrPc mRNA was predominantly localized within pyramidal cells of the hippocampus, large neurons of the thalamus and neocortex, and Purkinje cells of the cerebellum. In the placenta, not only PrPc mRNA was localized to a subpopulation of decidual cells at the highest levels, it was also expressed in the amnion and mesodermal layer of the yolk sac. Furthermore, PrPc mRNA was also expressed in the myometrium of the uterus and seminiferous tubule in the testis. However, signals were not obtained in the lung, spleen, liver of prenatals and other fetus tissues. The distribution of rat PrPc mRNA portrayed the levels which were different among the various types of cells, suggesting that its expression may be regulated in a tissue-specific manner.

Intraoperative radiation therapy for pancreatic carcinoma. The choice of treatment modality

Ninety patients with carcinoma of the pancreas treated between 1976 and 1990 were reviewed retrospectively. Intraoperative radiation therapy (IORT) in combination with external beam radiation therapy (EBRT) for localized but unresectable tumors (n = 29) prolonged survival significantly more than IORT alone (n = 16) (p < 0.01); it seems EBRT enhanced or contributed to the better results obtained with IORT plus EBRT. Moreover, IORT, alone or in combination, relieved pain. Adjuvant IORT for residual tumors (n = 20) might not effectively prolong survival, because the difference in survival rate between noncurative resection plus IORT and nonresection plus IORT in combination with EBRT was not significant. Curative tumor resection of stage III disease in combination with IORT (n = 9) resulted in significantly longer survival as compared with curative tumor resection alone (n = 8) (p < 0.05). It may be advisable to administer IORT in combination with EBRT to patients with advanced pancreatic carcinoma, avoiding aggressive tumor resection, when curative tumor resection cannot be performed.

Peripolar cells in guinea pigs under experimental hyperplasia of juxtaglomerular cells induced by long-term, low-dose calcium condition

The peripolar cell was described in the glomeruli of sheep by Ryan et al. in 1979 and these cells have subsequently been detected in many species (Ryan et al. 1982; Gall et al. 1986; Hanner et al. 1980). The peripolar cells are located at the junction between the podocytes of the glomerular capillaries and the epithelial lining of Bowmann's capsule, encircling the hilar region of the glomerular tuft. Functionally, the peripolar cells have been considered to be a part of the juxtaglomerular apparatus but the precise nature of the cells has not been identified (Gardiner et al. 1985). Recently, it has been found that an antibody against rat urinary kallikrein reacts positively with sheep peripolar cell (Gall et al. 1984). This finding has led to the suggestion that the peripolar cells may influence the renin secretion through the kallikrein-kinin system. In our experiments with long-term low-calcium condition accompanied with hyperplasia of juxtaglomerular cells the peripolar cells were easily detected. The results suggests that the increase in the number of peripolar cells is closely related to the hyperplasia of juxtaglomerular cells.

Necklace-like detachment of endothelial cell layer from arterial wall under low-calcium condition

The diversified morphological manifestations in various tissues and organs obtained by administration of differing amounts of calcium chelating agents were reported in previous papers (Yamaguchi et al 1981 a & b; 1982; 1990; 1993). In our recent research described here, administration of a moderate dose of Na2EDTA over the short term demonstrated necklace-like detachment from the arterial wall without disruption of the endothelial cell chain. Intercellular spaces in the media just beneath the detached endothelial cell layer was stained strongly with colloidal iron staining. Electron microscopic observation revealed that the detached endothelial cells showed a lot of elongated anchoring villi from the basal surface, usually seen at the luminal surface, adhered to the degenerative and thin flattened internal elastic lamellae. The alteration of the colloidal iron staining of the vascular wall under the low-calcium condition is suggested to be induced by loosening of the molecular structure of glycosaminoglycans (GAGs) as well as glycoproteins (GPs), comprising the important component of the intercellular matrix and elastic lamellae, which would induce a change in their pasty or viscous character. This would be an accelerative factor for detachment of endothelial cells. Moreover, the lack of the waving of the internal elastic lamellae, trapping of endothelial cytoplasmic processes among them, would play the decisive role in the total detachment of the endothelial cell layer. On the other hand, the low-calcium condition did not adversely influence the joining of endothelial cells. The pathognomatic mechanism will be discussed, with a comparison made to the angiolytic changes provoked by a large amount of Na2EDTA.

Electron microscopic studies on the formation of renal juxtaglomerular cell granules in the vitally stained mouse kidney

Mouse renal juxtaglomerular cells (JGC) were vitally stained with neutral red, and then fixed with glutaraldehyde to study by electron microscopy. Ultrastructural observation showed a large number of characteristic low electron dense juxtaglomerular granules (JGG) or low dense granules (LDG) in the cytoplasm of JGC. Many LDG contained a flocculent material with a dense core, which was as dense as the contents of JGG. Two kinds of LDG were observed. One of LDG was surrounded by single membrane and partial membrane, and another was surrounded by double membranes. Some LDG did not contain electron dense flocculent material. LDG were surrounded by rough endoplasmic reticulum (r-ER). Alteration of Golgi apparatus and r-ER was observed in JGC. Golgi complex did not associate with JGG and LDG.

Molecular cloning and expression of canine interleukin 8 cDNA

Molecular cloning of canine interleukin-8 (IL-8) was performed to establish a basis for its investigation in the canine immune system. From a cDNA pool constructed from LPS-stimulated popliteal lymph node cells, canine IL-8 cDNA covering the whole coding region was amplified by polymerase chain reaction. The nucleotide sequence of a canine IL-8 clone, designated pcIL-8#38, was highly similar to those of human, rabbit and porcine IL-8, and comprised 353 bp with an open reading frame that encoded 101 amino acids. Analysis of the deduced amino acid sequence of insert DNA in pcIL-8#38 showed 76.5, 80.2, and 87.0% similarities with human, rabbit and porcine IL-8 proteins, respectively. Insert DNA of pcIL-8#38 was transferred to a mammalian expression vector, pcDL-SR alpha 296, and transfected into Cos7 cells. The supernatant of the transfectant had neutrophil chemotactic activity when it was examined by the neutrophil migration assay, suggesting that our cloned cDNA was biologically active. The cloned canine IL-8 cDNA will be useful for canine inflammatory disease and comparative immunology research.

Aqueous flare increase after light exposure in age-related macular degeneration

An increase in anterior chamber flare is associated with many ocular conditions, including retinal diseases. We assessed anterior chamber flare in 18 patients (19 eyes) with exudative age-related macular degeneration using the Kowa flare-cell meter immediately before and 1 hour after exposure to 40 light flashes at a flash intensity of 300 W/s delivered with a Topcon fundus camera. Fourteen eyes showed a significant increase in flare 1 hour after light exposure (T = -3.452, p < 0.003, t-test). A second measurement in a subgroup of 10 patients exposed to 40 light flashes at a flash intensity of 36 W/s showed no significant change in flare 1 hour after light exposure. Multiple analysis of variance (two-way interaction) showed a highly significant difference between the two groups (F[1,27] = 8.66, p < 0.0066). We discuss possible mechanisms that may have produced these changes as well as implications of light exposure in various diagnostic and therapeutic settings.

Experimental idiopathic dilated cardiomyopathy under low-calcium condition

Administration of long-term, low-dose Na2EDTA leads to moderate or severe thinning of the right ventricular wall with or without rupture. These morphological manifestations are known to be site-dependent on the constriction of pulmonary arteries (Yamaguchi et al. 1993a). They sometimes ensue from aneurysmal dilatation and/or plexiform-like-lesion in a pulmonary artery (Yamaguchi et al. 1993b). The present contribution reports that experimental animals who survived for a longer period, maximum for 6 months, showed dilatation of the left ventricle with a mode-rately thin ventricular wall as well as right ventricular changes, which are similar to the morphological manifestations in idiopathic dilated cardiomyopathy.

Protective effects of serum thymic factor to Leptospira interrogans serovar Copenhageni infection in Mongolian gerbils

The susceptibility to Leptospira interrogans serovar copenhageni in Mongolian gerbils treated with 10 micrograms of serum thymic factor (FTS) 1 day before infection was examined. Susceptibility of gerbils treated 5 times with 10 micrograms of FTS was also investigated. Mortality of FTS-treated gerbils was significantly lower than that of controls when small challenge doses were used. To analyse the FTS-induced resistance to leptospiral infection, natural killer (NK) cell activity and macrophage activity were studied. Macrophage activity was unaltered but NK cell activity was enhanced in FTS-treated gerbils, with or without leptospiral infection. Since no side-effects of FTS were observed, this compound should be considered for the treatment of leptospirosis.