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Across Far East Asia, aspermic Fasciola forms are found endemically. They have abnormal spermatogenesis and oogenesis, and it is presumed that their progeny are produced parthenogenetically and clonally. Because of this, they are also termed parthenogenic Fasciola forms. Currently, there is no evidence that they do indeed reproduce parthenogenetically and clonally. In this study, the multilocus genetic type (MLG) in 12 microsatellite markers of adult flukes and their subsequent progeny larvae were analysed using two laboratory aspermic Fasciola triploid strains. The MLGs of adults and their larvae were identical for all markers evaluated, suggesting that these strains reproduce their progeny clonally. The deviation between theoretical and actual frequency within the larvae genotype of the Fh_6 locus resulted in the inability for self-fertilization within individual adult flukes. These findings strongly suggested that aspermic Fasciola forms reproduce their progeny by means of parthenogenesis, possibly gynogenesis.

This study examined whether propolis, which had many biological activities, affected body fat and lipid metabolism. Four-week-old Wistar rats were fed a control or propolis diet for 8 wk. The control group was fed a high-fat diet, the low and the high group were fed a high-fat diet supplemented with 0.5% (w/w) and 0.05% (w/w) propolis, respectively. The weight of total white adipose tissue of the high group was lower than that of the control group. The level of PPARγ protein in the adipose tissues of the high group was significantly lower than that of the control group. In plasma and the liver, the high group showed a significantly reduced level of cholesterol and triglyceride compared to the control group. The liver PPARα protein level of the high group was significantly higher than that of the control group. The liver HMG-CoA reductase protein in the high group was also significantly lower than that in the control group. Results from rats on an olive oil loading test were used to investigate whether propolis inhibited triglyceride absorption. The serum triglyceride level of the group, which received propolis corresponding to the daily dose of the high group, was significantly lower than that of the control group. It is possible that the administration of propolis improves the accumulation of body fat and dyslipidemia via the change of the expression of proteins involved in adipose depot and lipid metabolism.

Two cDNA encoding red sea bream DE-1 and DE-2 phospholipases A2 (PLA2) were cloned from the hepatopancreas of red sea bream, Pagrus (Chrysophrys) major. The cDNA of DE-1 PLA2 encoded a mature protein of 125 amino acid residues with an apparent signal peptide of 20 residues and propeptide of 5 residues, and that of DE-2 PLA2, a mature protein of 126 amino acid residues with an apparent signal peptide of 17 residues and propeptide of 6 residues. Comparison of the predicted amino acid sequences for mature DE-1 and DE-2 PLA2 showed that both proteins contain 14 cysteines including Cys 11 and 77 and a pancreatic loop, which are commonly conserved in group IB PLA2; however, the identity in amino acid sequence between DE-1 and DE-2 PLA2 was low (47%). A previous report concerning the cDNA cloning of red sea bream gill G-3 PLA2 and the present results represent the first cloning and sequencing of three distinct isoforms of group IB PLA2 in a single fish species, red sea bream. Reverse transcription-polymerase chain reaction analysis showed that DE-1 PLA2 mRNA was expressed in the hepatopancreas, pyloric ceca, intestine, spleen, gonad, stomach, and kidney, whereas gill G-3 PLA2 mRNA was expressed only in the gills and gonad. The expression of DE-2 PLA2 mRNA was detected in all of the tissues analyzed. These results indicate that three distinct isoforms of group IB PLA2, DE-1 and DE-2 PLA2 in hepatopanceas and gill G-3 PLA2, are expressed in a tissue-specific manner in red sea bream.

Well-established mechanisms for regulation of protein activity include thiol-mediated oxidoreduction in addition to protein-protein interactions and phosphorylation. Nucleoredoxin (NRX), glutaredoxin (GRX), and thioredoxin (TRX) have been shown to act as a potent thiol reductase and reactive oxygen species regulator. They constitute a oxidoreductase superfamily and have been suggested as a candidate operating in the redox regulation of gene expression. We demonstrated here that intracellular localization of these redox molecules differ from each other and that the redox molecules differentially regulate NF-kappaB, AP-1, and CREB activation induced by TNFalpha, PMA, and forskolin and by expression of signaling intermediate kinases, NIK, MEKK, and PKA in HEK293 cells. This is a first report that describes involvement of NRX and GRX and differences from TRX in transcriptional regulation of NF-kappaB, AP-1, and CREB in living cells.

More than 90 spices of herpes viruses have been isolated from wide variety of non-human animals. Among these herpes viruses, only B virus (Cercopithecine herpesvirus 1), the natural host of which is macaque monkey, is severely pathogenic to human. B virus infects human through handling infected monkey tissues or by injury caused by infected monkey, and severe encephalitis ensues. However, in 1997 mucocutaneous infection without injury was reported. The genome structure and immunogenic property of B virus is similar to those of human herpesvirus(HSV). And pathogenecity of B virus to monkey is also similar to that of HSV to human. Although the natural host of pseudorabiesvirus (Suid herpesvirus 1) is swine, it infects wide range of animals and causes severe nervous symptoms. However, the pathogenicity to human is controversial.

An improved method for constructing canine herpesvirus (CHV) recombinants expressing foreign genes by using the lacZ-TK gene cassette as a double selectional marker was developed. A recombinant CHV carrying the lacZ-TK gene at a targeted gene locus was constructed and used as a parental virus for generating new recombinants. The parental virus formed blue plaques and was sensitive to TK-specific drugs, while newly generated recombinants, in which the lacZ-TK gene was replaced with the desired foreign gene, become both resistant to the TK-specific drugs and formed white plaques. Recombinants were isolated by using the combination of drug selection and color selection. This improved method allows construction of recombinant CHV with great ease, because the drug selection can enrich the frequency of recombinant CHV from 0.01-0.1% to 10-80%. This method was employed to construct a recombinant CHV that expressed rabies virus (RV) glycoprotein (G protein).

Clinical measurements on gingival indices and morphologic observations were performed in this study to verify the defending mechanism of gingival soft tissue against foreign invasions from the perspective of epithelial adhesion/attachment to implant surfaces in the monkey mandible. The following zones were observed using scanning electron microscopy: (1) plaque zone, suggesting susceptibility of the gingival tissue to bacterial invasion; (2) nude zone, demonstrating indirect adhesion of epithelial cells to the implant surface through the mucous layer and preventing bacterial invasion; and (3) epithelial cell attached zone, having greater bond strength of epithelial cells at the cell-implant interface as compared to cell-cell bonding within the epithelial cell layer. This study suggested that epithelial cell attachment/adhesion may play a dominant role in retaining the successful condition of a dental implant.

The foregut and associated glands of a digenetic trematode, Paragonimus miyazakii, were examined in the forebody by transmission and scanning electron microscopy as well as by light microscopy, and their functional roles were discussed. The foregut is lined with a general tegument without spines and sensory receptors throughout its length, although it consists of the mouth, pharynx, and esophagus. This foregut tegument is regionally and intraregionally modified in appearance, suggesting the performance of auxiliary functions in digestion. This appearance is characterized by long, frequent cytoplasmic extensions of the apical tegument around the middle portion of the mouth and the anterior esophagus. Electron-dense granules and multimembranous and multilamellar bodies are developed in the tegument to various degrees, and elaborately in the apical layer of the prepharynx. A single type of unicellular gland is embedded in the antero-middle part of the worm in small groups. The gland cells synthesize clear secretory granules as a chief product, each granule with a pleomorphic, dense, core-like inclusion. Mature granules are elliptical in shape, approximately 500 nm in diameter, and are subsequently discharged into the prepharyngeal foregut lumen after passing through the elongated cytoplasm of the gland cell. In the prepharynx and pharynx, host blood cells are apparently processed for digestion. In the wide lumen of the esophagus, foodstuff could undergo sufficient digestion prior to absorption by the cecal epithelium.

The effect of a high fat diet (HFD) on renal function, renal mitochondrial function and intrarenal oxygen-free radial scavenging activity were examined in the ischemia-reperfusion model of the rat kidney. Whether of not a novel lipophilic antioxidant (BO653) could minimize this effect in vivo was also investigated. Thirty minutes renal ischemia was introduced by vascular clamp in rats with or without HFD (cholesterol 1.25%). Some of the HFD rats received BO653 by gastric gavage. Creatinine clearance (Ccr) was measured 24 hours following the injury. Mitochondrial oxygen consumption and thiobarbituric acid reactive substance (TBARS), superoxide dismutase (SOD), glutathione peroxidase (GPX) and alpha-tocopherol were measured in the kidney before, 30 min ischemia and 30 min after reperfusion. HFD significantly reduced Ccr after ischemia-reperfusion (45% decreased compared to normal diet), which was ameliorated by BO653. Thirty-minute ischemia deteriorated the mitochondrial function in the normal diet (ND) group, high fat diet (HFD) group and high fat diet + BO653 (HFD + BO) group. Thirty-minute reperfusion ameliorated the mitochondrial function in all those groups. The kidney content of TBARS was not increased after the ischemia-reperfusion in all these groups. In the HFD group, the kidney content of GPX was higher than in the ND group during ischemia-reperfusion, but in the HFD group, the kidney content of SOD was significantly decreased after the thirty-minute ischemia. Thirty-minute ischemia decreased the kidney content of alpha-tocopherol in the HFD group, which was recovered by the thirty-minute reperfusion. In conclusion, a high fat diet deteriorates ischemia-reperfusion injury of the rat kidney and BO653 ameliorated this effect judged by creatinine clearance and renal mitochondrial function. Reperfusion injury could not be confirmed in the present model based on the results of lipid peroxidation and oxygen-free radical scavenging enzyme activity.

To determine whether brain natriuretic peptide (BNP) affects intraocular pressure (IOP), aqueous humor dynamics, and cyclic guanosine monophosphate (cGMP) concentration in the aqueous humor of the rabbit eye.Twenty microliters of 10(-4) M and 10(-5) M (2 nmol, 0.2 nmol) BNP or atrial natriuretic peptide (ANP) were injected intravitreally into rabbit eyes, after which the IOP was measured using a pneumatonometer. Aqueous humor dynamics were studied at approximately 6 hours after the intravitreal injection of 2 nmol BNP. Aqueous humor flow was measured by fluorophotometry, and outflow facility was measured by the two-level constant pressure perfusion method, whereas uveoscleral outflow was measured by the fluorescein isothiocyanate-dextran perfusion method. The concentration of cGMP in the aqueous humor at 6 hours after injection of 2 or 0.2 nmol BNP also was measured by enzyme immunoassay.Intravitreal administration of BNP or of ANP caused a decrease in IOP, with a maximum effect at approximately 6 hours after the injection. Total outflow facility in eyes treated with 2 nmol BNP increased by 29%, although the aqueous humor flow and uveoscleral outflow did not show significant changes. The concentration of cGMP in the aqueous humor increased significantly in BNP-treated eyes.Intravitreal injection of BNP into rabbit eyes reduced IOP because of an increase in the outflow facility. Brain natriuretic peptide also increased the concentration of cGMP in the aqueous humor. It is probable that BNP-activated guanylate cyclase induced an upregulation of cGMP in the aqueous humor.

Blastodermal chimeras were constructed by transferring quail cells to chick blastoderm. Contribution of donor cells to host were histologically analyzed utilizing an in situ cell marker. Of the embryos produced by Injection of stage Xl-XIII quail cells into stage XI-2 chick blastoderm, more than 50 percent were definite chimeras. The restriction on the spatial arrangement of donor cells was induced by varying the stage of host. Ectodermal chimerism was limited to the head region and no mesodermal chimerism was shown when the quail cells were injected into stage XI-XIII blastoderm. Mesodermal and ectodermal chimerisms were limited to the trunk, not to the head region, when the quail cells were injected into the stage XIV-2 blastoderm. In these chimeras, however, some of the injected quail cells formed ectopic epidermal cysts. Consequently, the stage XIV-2 blastoderm may become intolerant of the injected cells. Our results suggest that it is possible to obtain chimeras that have chimerism limited to a particular germ layer and region by varying the stage of donor cell injection. Injected quail cells contributed to endodermal tissues and primordial germ cells regardless of the injection site. The quail-chick blastodermal chimeras could be useful in the production of a transgenic chicken and in the investigation of immunological tolerance.

In order to analyse the spinal tract formation at early stages of development in avian embryos, chick-quail spinal cord chimeras were prepared and species-specific monoclonal antibodies (MAb) were developed. MAbs CN, QN and CQN uniquely stained chick, quail, and both chick and quail nervous tissues, respectively. All three antibodies appeared to bind to the same membrane molecule, but to different epitopes. Cord reversal revealed the features of axonal growth of both cord interneurons and dorsal root ganglion cells. Quail cord interneurons grew along an originally ventral marginal layer in the quail cord transplanted in a reversed position, then turned toward the ventral side at the boundary between the graft and the host, and grew along the host chick ventral marginal layer. Central axons of dorsal root ganglia were restricted to the ventrolateral region of the cord which originally formed the dorsal funiculus. These results suggest that cord interneurons and dorsal root ganglion cells actively select to grow along specific regions of the cord and that spinal tract formation appears to be determined by cord cells, and not by sclerotome cells.

The cells treated with cadmium chloride showed severe changes: ribosomes disappeared, mitochondria showed various degrees of destruction, and the endoplasmic reticulum had a swollen and beadlike appearance. In cells treated with mercuric chloride, ribosomes increased in their density and rosette-like polysomes were predominantly observed. The effects of these two metallic ions were discussed.

Effects of 7-ethoxycarbonyl-6,8-dimethyl-4-hydroxymethyl-1 (2H)-phthalazinone (EG626) on the spinal trigeminal nucleus (STN), ventral posteromedial nucleus (VPM), and sensory cortex were examined in cats anesthetized with alpha-chloralose in comparison with the effects of morphine. EG626 produced a dose-dependent inhibition of the polysynaptic components of the cortical field potentials upon VPM stimulation and either facilitatory or inhibitory effects on the polysynaptic components of the VPM field potential upon stimulation of the medial lemniscus, while the drug failed to affect the STN field potential with trigeminal nerve stimulation. Morphine inhibited the postsynaptic components of the STN field potentials and to a lesser extent, the polysynaptic components of the cortical field potential; and the effects of morphine on the VPM field potential were similar to those seen with EG626. Pretreatment of the animal with naloxone antagonized the facilitatory effect on the VPM field potentials produced by morphine, but not those by EG626. Morphine and EG626 induced either a prolonged increase in the blood flow or transient increase followed by a decrease in the blood flow in the VPM. These results suggest that EG626 may impair the polysynaptic transmission and/or neuron excitability in the sensory cortex and the VPM at least partly due to the change in blood flow there as does morphine. Unlike morphine, however, EG626 did not produce any obvious effect on the STN.

These experiments bring new information concerning the immunological status after birth of quail----chick spinal cord chimeras. Such birds have been produced using recipient flocks of chickens different from those in our previous experiments. The breakdown of tolerance after hatching has been recorded and found to vary with the origin of the embryos. Chickens of broiler JA 657 strain and of a white leghorn strain raised in Japan started to exhibit signs of neural graft rejection later in life than the white leghorn chickens from a French breeder used in our previous studies. As previously described, in two animals, long-term tolerance was observed only for allogeneic chick----chick neural tube grafts. In one chimera the neurological syndrome resulting from rejection was reversible, and no signs of immune attack of the grafted central nervous tissue could be detected at sacrifice. This and other observations reported in this article strongly support the contention that the host immune response to foreign neural tissues starts in peripheral nerves and ganglia where no blood-brain barrier exists rather than in the spinal cord. A humoral response of the host against non-polymorphic quail antigens present on fibroblasts was observed in all birds at the time of rejection.

Agents responsible for the entry of cholesterol-bearing lipoproteins into the arterial wall represent local risk factors in atherogenesis. In an attempt to identify these agents, we inserted a catheter into the ascending aorta of rabbits and 5 ml of arterial blood sample was withdrawn. The contraction of the aortic strip of rabbit against Piper and Vane's antagonists with application of this sample was observed. Samples obtained after feeding of 1 Gm/Kg of cholesterol and after an intravenous administration of thromboxan A2 (TXA2) contracted the aortic strip. Samples from non-treated rabbits or those obtained after intravenous administration of 10 microgram of epinephrine or norepinephrine did not contract the strip. Previous administration of 20 mg/Kg of indomethacin decreased the contraction developed after feeding of 1 Gm/Kg of cholesterol. It was suggested that TXA2 might be released into the arterial blood by the ingestion of cholesterol and might be one of the agents repsonsible for the entry of lipoproteins.