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Terrestrial resource pulses can significantly affect the community dynamics of freshwater ecosystems. Previously, its effect on the river community is considered to be stronger in summer, whereas weaker in winter when terrestrial invertebrates are less abundant. The movement of the terrestrial earthworms is triggered in winter, so they may be supplied to winter rivers as terrestrial resource pulse, but little is known about it. Here, we report that the massive numbers of the terrestrial earthworms were supplied intensively to an upstream of the small river in early winter. In particular, we found large numbers of megascolecid earthworms were supplied in an upstream of the small river in Northern Japan. Furthermore, we observed that supplied earthworms were consumed by salmonid fish species (masu salmon, white spotted char and rainbow trout) and aquatic invertebrates (gammarid amphipod, planarian flatworm, and stonefly larvae). These findings suggest that the terrestrial earthworms may play a key role in ecosystem functioning in winter when severe and other resources are scarce., Competing Interests: We have no conflict of interest., (© 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Although paedomorphosis is widespread across salamander families, only two species have ever been documented to exhibit paedomorphosis in Hynobiidae. One of these two exceptional species is Hynobius retardatus in which paedomorphosis was first reported in 1924, in specimens from Lake Kuttara in Hokkaido. This population became extinct after the last observation in 1932; since then, no paedomorphs of this species have been reported anywhere. Here, we report the rediscovery of paedomorphs of this species. Three paedomorph-like male salamanders were collected from a pond in the south Hokkaido in December 2020 and April 2021; in size, these specimens were similar to metamorphosed adults but they still displayed larval features such as external gills and a well-developed caudal fin. An artificial fertilization experiment demonstrated that they were sexually compatible with metamorphosed females, thus, confirming them to be paedomorphs. Future efforts to find additional paedomorphs in this and other populations are required to assess the prevalence of paedomorphosis in H. retardatus and to improve understanding of the ecology and evolution of paedomorphisis in Urodela., (© 2021. The Author(s).)

Frogs of the genus Microhyla include some of the world's smallest amphibians and represent the largest radiation of Asian microhylids, currently encompassing 50 species, distributed across the Oriental biogeographic region. The genus Microhyla remains one of the taxonomically most challenging groups of Asian frogs and was found to be paraphyletic with respect to large-sized fossorial Glyphoglossus . In this study we present a time-calibrated phylogeny for frogs in the genus Microhyla , and discuss taxonomy, historical biogeography, and morphological evolution of these frogs. Our updated phylogeny of the genus with nearly complete taxon sampling includes 48 nominal Microhyla species and several undescribed candidate species. Phylogenetic analyses of 3,207 bp of combined mtDNA and nuDNA data recovered three well-supported groups: the Glyphoglossus clade, Southeast Asian Microhyla II clade (includes M. annectens species group), and a diverse Microhyla I clade including all other species. Within the largest major clade of Microhyla are seven well-supported subclades that we identify as the M. achatina , M. fissipes , M. berdmorei , M. superciliaris , M. ornata , M. butleri , and M. palmipes species groups. The phylogenetic position of 12 poorly known Microhyla species is clarified for the first time. These phylogenetic results, along with molecular clock and ancestral area analyses, show the Microhyla-Glyphoglossus assemblage to have originated in Southeast Asia in the middle Eocene just after the first hypothesized land connections between the Indian Plate and the Asian mainland. While Glyphoglossus and Microhyla II remained within their ancestral ranges, Microhyla I expanded its distribution generally east to west, colonizing and diversifying through the Cenozoic. The Indian Subcontinent was colonized by members of five Microhyla species groups independently, starting with the end Oligocene-early Miocene that coincides with an onset of seasonally dry climates in South Asia. Body size evolution modeling suggests that four groups of Microhyla have independently achieved extreme miniaturization with adult body size below 15 mm. Three of the five smallest Microhyla species are obligate phytotelm-breeders and we argue that their peculiar reproductive biology may be a factor involved in miniaturization. Body size increases in Microhyla-Glyphoglossus seem to be associated with a burrowing adaptation to seasonally dry habitats. Species delimitation analyses suggest a vast underestimation of species richness and diversity in Microhyla and reveal 15-33 undescribed species. We revalidate M. nepenthicola , synonymize M. pulverata with M. marmorata , and provide insights on taxonomic statuses of a number of poorly known species. Further integrative studies, combining evidence from phylogeny, morphology, advertisement calls, and behavior will result in a better systematic understanding of this morphologically cryptic radiation of Asian frogs., Competing Interests: Nikolay A. Poyarkov is an Academic Editor for PeerJ. Suranjan Karunarathna is employed by Nature Explorations and Education Team (Sri Lanka). Luan Thanh Nguyen is employed by Asian Turtle Program—Indo-Myanmar Conservation (Vietnam). Other authors have declared that no competing interests exist., (© 2020 Gorin et al.)

Hynobius dunni is a salamander species of the genus Hynobius endemically distributed in eastern Kyushu in southwestern Japan. In this study, we determined the complete mitochondrial genome sequence and clarified the phylogenetic position of this species. The mitochondrial genome was 16,47 bp in length and encoded 13 protein, 2 ribosomal RNA, and 22 transfer RNA genes. Phylogenetic tree based on 13 protein-coding genes revealed that H. nebulosus were the most closely related species within the Hynobius species. The data identified in this study will be useful for population and conservation genetic studies of Hynobius species., (© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

We examine the phylogenetic structure and morphological differentiation within the Hynobius kimurae-H. boulengeri species complex-a widely-distributed group of stream-breeding hynobiid salamanders, inhabiting montane areas of western, central and eastern parts of Honshu Island, Japan. Phylogenetic relationships were assessed based on analyses of mitochondrial (mtDNA) and nuclear (nuDNA) gene fragments for a total of 51 samples representing 23 localities covering the entire range of the species complex. Morphological study included one-way analysis of variance (ANOVA) and principal components analysis (PCA) analyses of 26 morphometric and six meristic characters for 38 adult specimens of H. kimurae and three adult specimens of H. boulengeri . MtDNA genealogy supported monophyly of the H. kimurae-H. boulengeri complex, which is sister to all other Hynobius except H. retardatus . The complex is subdivided into three major clades, corresponding to the Eastern (Clade I) and Western (Clade II) populations of H. kimurae sensu lato, and to H. boulengeri (Clade III). Monophyly of H. kimurae sensu lato is only moderately supported by mtDNA, while nuDNA suggested that the Western form of H. kimurae is closer to H. boulengeri than to the eastern form. The time of the split of the H. kimurae-H. boulengeri complex is estimated as late Miocene and coincides with intensive crust movement in western Japan. Divergence between Clades I and II took place in early Pliocene and was likely influenced by the uplift of Central Japanese Highlands. All three clades were found to be different in a number of morphological characters, allowing us to describe the eastern form of H. kimurae as a new species, Hynobius fossigenus sp. nov ., Competing Interests: The authors declare that they have no competing interests.

Bufo japonicus formosus (Eastern-Japanese common toad) is endemic to Eastern Japan. As with many Japanese amphibians, little is known about its terrestrial life, especially during the nonbreeding season. This species persists even in highly disturbed urban areas where many other amphibian species have already been extirpated. An understanding of how such species use habitats within remnant landscapes may help to inform management strategies for the conservation of urban ecosystems. We examined the nightly movement patterns, distance traveled, movement range, and microhabitat selection of non-breeding adult B. j. formosus at an urbanized site, using fluorescent powder tracking. We evaluated the usefulness of this tracking method through this survey. We found that the nightly distances traveled by these toads varied greatly among individuals and nights. No sexual differences in movement pattern, distance traveled, and movement range were detected. However, body size significantly affected distance traveled and movement range. We found that toads tended to use areas covered with grasses and mosses more frequently than expected, and to avoid paved areas. Fluorescent powder tracking was effective for the elucidation of movement patterns and habitat selection of amphibians. Our results provide useful information for the conservation of amphibians, especially for species inhabiting urbanized areas.

Arteritis induced in rats by vasodilators, fenoldopam and theophylline, was examined immunohistochemically for expressions of inducible type of nitric oxide synthase (iNOS), basic fibroblast growth factor (bFGF) and tumor growth factor-beta1 (TGF-beta1). Rats were administered fenoldopam for 24 hours by intravenous infusion with or without following repeated daily oral administrations of theophylline. Irrespective of theophylline administration, iNOS antigens were remarkably abundant in ED-1-positive cells on day 5 and 8 post-fenoldopam-infusion (DPI); bFGF antigens were remarkably abundant in ED-1-positive cells on 1 and 3 DPI; TGF-beta1 antigens were observed in ED-1-positive cells on and after 5 DPI. These results suggest that the peak expression of iNOS antigen was followed by that of bFGF antigen, and bFGF may have a suppressive effect on iNOS expression in these rat arteritis models. On the other hand, TGF-beta1 was not considered to have a suppressive effect on iNOS expression in these models.

The antibiotic nitrofurazone (NF) has been known for its testicular toxicity; in contrast, much less is known about its effect on the liver. NF was given to male rats for up to 7 consecutive days to evaluate NF-induced effects on the liver. NF increased hepatocyte DNA synthesis and liver weight in a dose-dependent manner, with no apparent histological or biochemical evidence of cell damage or loss. The hepatocyte proliferation ceased after a few days despite the continuation of treatment. The absence of cell damage indicates that NF-induced hepatocyte proliferation is different from regenerative proliferation that is seen after partial hepatectomy or cell necrosis.

Nitrofurazone (NF) has been previously demonstrated to induce testicular toxicity with 4 weeks of oral administration in rats. In the present study, rats were administered NF to assess whether testicular toxicity becomes evident with a 2-week administration period. Male Sprague-Dawley rats were administered oral doses of NF at 50 mg/kg for 2 or 4 weeks. Another group was administered NF at 100 mg/kg for 2 weeks. The control animals received the vehicle (0.5% methylcellulose) for 4 weeks. Organ weights of the testis and epididymis were significantly decreased in all NF-administered animals, and seminiferous tubules were severely atrophied, due to a total absence of spermatids and degeneration and desquamation of spermatocytes. In the epididymis, decreased numbers of spermatozoa were evident in the ducts. In rats that were administered NF at 50 mg/kg, the changes in the epididymis in the 2-week group were less prominent than those in the 4-week group. In the testis, however, the changes were similar in both groups. Thus it was demonstrated that NF-induced testicular toxicity comparable to that observed after 4 weeks of administration is also detectable after 2 weeks.

The effect of recombinant human interleukin-11 (rHuIL-11) on myelosuppressive nimustine (ACNU)-induced thrombocytopenia was assessed in nonhuman primates. A single intravenous (i.v.) injection of ACNU (15 mg/kg) was administered to cynomolgus monkeys on day 0. rHuIL-11 (100 microg/kg/day) or the vehicle was given subcutaneously (s.c.) from day 1 to day 21. In monkeys receiving ACNU, the circulating platelet count decreased to a low of 42 +/- 6 x 10(9)/L by day 21 but returned to pretreatment levels (375 +/- 48 x 10(9)/L) on day 30. Administration of rHuIL-11 prevented severe thrombocytopenia; the platelet count fell only to 138 +/- 23 x 10(9)/L on day 18, and platelet recovery was faster (458 +/- 91 x 10(9)/L by day 27) compared with that of the control animals. The size of bone marrow megakaryocytes from rHuIL-11-treated animals was larger than that of the controls, indicating that rHuIL-11 stimulated megakaryopoiesis in a myelosuppressive condition. Treatment with ACNU also caused leukopenia and moderate anemia. rHuIL-11 transiently and slightly decreased the white blood cell (WBC) and red blood cell (RBC) counts. Conversely, rHuIL-11 accelerated recovery of RBC count in the late administration period. These results support the assertion that rHuIL-11 may be an important therapeutic agent for reducing the severity and duration of thrombocytopenia following cancer chemotherapy.

The common lipopolysaccharide (LPS)-induced gastric lesions, such as erosions or ulcers, have been investigated in depth. Little is known, however, about the acute gastric lesions following a high dose of LPS. In a time-course study, ICR female mice were given a high subcutaneous dose of LPS (50 mg/kg). Mice were sacrificed at 4, 6, 12, and 24 hours after dosing and were assessed histopathologically for acute gastric lesions. The major gastric changes were seen in the fundic region and included vacuolar degeneration of parietal cells and apoptosis of chief cells. The vacuole in parietal cells was apparent as early as 4 hours postinjection (PI), and apoptosis of chief cells was apparent at 12 hours PI. Thrombus formation, in contrast, was not seen until 24 hours PI. No erosion, ulcer, or hemorrhage was seen in any gastric region in any of the treated animals at 24 hours PI. These results indicate that a subcutaneous high dose of LPS in mice causes vacuolar degeneration of parietal cells and apoptosis of chief cells before thrombus formation or subsequent ulcerative lesions.

Piperonyl butoxide, alpha-[2-(2-butoxyethoxy)ethoxy]-4,5-methylenedioxy-2-propyltol uene, is a widely used pesticide-synergist. Recently, results were reported indicating that piperonyl butoxide is a hepatocarcinogen in rat. Since the underlying mechanism was not elucidated, we examined the effects on rat liver cells in detail. For this purpose male F344 rats were administered piperonyl butoxide mixed in the diet at concentrations of 0 (negative control), 0.05, 0.2 or 2% for 2 days, 1, 2, and 4 weeks. As a positive control, phenobarbital was administered to rats for up to 4 weeks as a 0.1% solution in the drinking water. Increased liver weight, centrilobular hepatocellular hypertrophy due to increased smooth endoplasmic reticulum, decreased numbers and areas of connexin 32-positive spots per hepatocyte, and increased cell proliferation were observed in rats treated with 0.2 and 2% piperonyl butoxide. Similar results were obtained for 0.1% phenobarbital treated rats. Hepatocellular necrosis suggestive of hepatotoxicity was also observed in the 2% piperonyl butoxide group. These results indicate that the promoting mechanism of piperonyl butoxide in hepatocarcinogenesis is similar to that of phenobarbital, involving an ability to induce CYP isoenzymes and inhibit gap junctional intercellular communication. In addition, increased cell proliferation following hepatocellular necrosis may also play a role at high doses.

Antitumor activities of zinostatin stimalamer (YM881) were examined in human hepatoma cell lines (SK-Hep1 and HuH2) and VX2 liver tumor-bearing rabbits. YM881 inhibited the growth of human hepatoma cells in a dose-dependent manner. The IC50 values of YM881 causing a 50% inhibition of growth of SK-Hep1 and HuH2 cells were 6.7 and 27 nM, respectively. In VX2 tumor-bearing rabbits, administration of YM881 suspended in Lipiodol, an iodinated fatty acid ethylester of poppyseed oil, (YM881/Lipiodol suspension, 0.2 mg/0.2 ml/body) into the hepatic artery showed significant (p < 0.01, vs. sham-operated and Lipiodol-treated groups) inhibitory effects on tumor growth and histopathological changes at 1 and 2 weeks after administration. In contrast, Lipiodol (0.2 ml/body) tended to inhibit the growth of VX2 tumor (p < 0.1, vs. sham-operated group) at 1 week after administration, but showed only moderate effects at 2 weeks after administration. Minimal necrosis was observed at 1 and 2 weeks after administration of Lipiodol, and histopathological findings were similar to those in the sham-operated group. From the present study, it is suggested that YM881/Lipiodol suspension showed antitumor activity in VX2 tumor-bearing rabbits presumably due to the inhibition of the growth of hepatoma cells by YM881 itself. Lipiodol, on the other hand, is considered to augment the antitumor activity of YM881 by maintaining high YM881 concentrations in tumor tissue.

The aims of this study were to investigate the effect of aminoguanidine (AG) on slowing of motor nerve conduction velocity (MNCV) of the sciatic nerve in streptozocin-induced diabetic rats and to assess its mechanism of action. The MNCV of the sciatic nerve was measured electrophysiologically in diabetic rats treated with and without AG for 16 weeks. To elucidate the action of AG, morphological lesion and abnormality of polyol pathway metabolism in the nerve were examined and tissue levels of advanced glycosylation end-products (AGE) were determined as an indicator of AGE accumulation in tissue. Diabetic rats were treated with AG at three doses of 10, 25 and 50 mg/kg for 16 weeks. Myelinated fiber morphometry and nerve Na+,K(-)-ATPase activity were determined. The AGE levels in renal cortex were measured by a specific ELISA. Aminoguanidine dose-dependently ameliorated slowing of MNCV 16 weeks after the treatment without changing body weight or blood glucose levels. No difference in myelinated fiber morphometry or Na+,K(+)-ATPase activity with or without AG treatment was detected in diabetic rats. Diabetes increased the AGE level in the renal cortex by six times compared to non-diabetic rats, and AG reduced the rise in the AGE level by 40%. The MNCV was inversely correlated with the AGE levels. We conclude that improvement of conduction slowing by AG in experimental diabetes may be through decreasing the AGE level in the peripheral tissues. Aminoguanidine may have a therapeutic potential in controlling diabetic peripheral neuropathy.

Three-week oral administration of 4-(decahydro-6-methyl-3-oxo-cyclopenta(f)quinoline-7-yl)valeric acid (32-1328) in the diet supplemented at concentrations of 0.1% or 0.3% was associated with hepatomegaly and hypotriglyceridemia in male F344 rats. Electron microscopic examination of the liver revealed a remarkable increase of peroxisomes in hepatocytes both in number and size. Biochemically, there were increased activities of peroxisomal marker enzymes including the heat-labile enoyl-CoA hydratase and catalase while the mitochondrial enoyl-CoA hydratase activity was unchanged after feeding of 32-1328. These findings indicate that 32-1328 can exert peroxisome-proliferating activity to rat liver in a manner similar to typical peroxisome proliferators such as clofibrate or di(2-ethylhexyl)phthalate.

Anti-tumor activities of zinostatin stimalamer (YM 881) were examined using human hepatoma cell lines (SK-Hep1 and HuH 2) and VX2 liver tumor-bearing rabbits. YM881 inhibited the growth of human hepatoma cells in a dose-dependent manner. The IC50 values of YM881 against SK-Hep 1 and HuH 2 cells were 6.7 and 27 mM, respectively. In VX2 tumor-bearing rabbits, administration of YM 881 suspended in iodinated fatty acid ethylesters of poppyseed oil (YM 881/Lipiodol suspension, 0.2 mg/0.2 ml/body) into the hepatic artery showed significant (p < 0.01, vs sham-operated and Lipiodol-treated groups) inhibitory effects on the growth and pathological changes 1 and 2 weeks after administration. On the other hand, Lipiodol (0.2 ml/body) showed a tendency to inhibit the growth of VX2 tumor (p < 0.1, vs sham-operated group) 1 week after administration, but it showed only moderate effects on the VX2 tumor growth 2 weeks after administration. Minimal necrosis was observed 1 and 2 weeks after administration of Lipiodol, and these pathological findings were similar to those in the sham-operated group. From the present study, it is suggested that YM 881/Lipiodol suspension showed the anti-tumor activity against VX2 tumor-bearing rabbits, presumably due to the inhibition of the growth of hepatoma cell by YM 881 per se. On the other hand, Lipiodol is considered to augment the anti-tumor activity by maintaining high YM881 concentrations in tumor tissue.

Testicular toxicity induced by adriamycin (ADR) was studied using quantitative histopathological methods. Nine-week old male rats were received a single dose of 8 mg/kg ADR. At 3, 7, 14 and 21 days after the treatment, animals were sacrificed for histopathological evaluation. Numbers of seminiferous epithelia were counted in seminiferous tubule of spermatogenic stages I, II, V, VII and XII. A decrease in spermatogonia was observed in seminiferous tubules of stages I, II and V at 3 days after the treatment. Thereafter, numbers of other types of seminiferous epithelia decreased following progress of spermatogenic cycle. Analysis of spermatogenic cycle movement and germ cell differentiation suggested that ADR was highly effective in killing spermatogonia type A, and the severity of ADR damage would be different depending on subtypes of spermatogonia type A and spermatogenic stages.

The potential short-term promoting effects of cigarette smoke on the development of tumors in the respiratory system were investigated in male Syrian golden hamsters. Three groups (1, 2 and 3) of 30 animals each received a single s.c. injection of 100 mg/kg body wt of diethylnitrosamine (DEN) at the commencement of experiment 1. They were then exposed to non-filter cigarette (NC) smoke, filter-tip cigarette (FC) smoke and sham smoke respectively, in a Hamburg II type smoking machine from week 1 to week 12. In addition, groups 4, 5 and 6 (10 animals each) were exposed to the NC smoke, FC smoke or sham smoke respectively, for the same time period without prior DEN treatment. In the DEN-treated groups, epithelial hyperplasias and/or papillomas were induced, the incidences and numbers/animal of these lesions in groups 1 and 2 being significantly increased as compared to group 3 values. In experiment 2, two groups of 25 hamsters each were exposed to cigarette smoke or sham smoke for up to 12 weeks, five animals in each group being killed for immunohistochemical analysis using BrdU antibodies and measurement of lipid peroxides in the lung and serum at weeks 1, 2, 4, 8 and 12. Small aggregations of macrophages (smoke cells) in the lung alveoli was observed in the smoke-exposed group, but no significant increase in the numbers of BrdU positive cells in any compartment of the respiratory system was apparent. Animals of this group showed a tendency for increased lung malondialdehyde levels at weeks 2 and 12, but not weeks 4 and 8.

The effects of NaCl on lipid peroxidation levels in gastric mucosa and urine were investigated in male Wistar rats. The animals were fed NaCl-supplemented diet at concentrations of 4.0, 2.0, 1.0, 0.5, 0.25 and 0% (control) for 5 weeks. Further groups were maintained on the 4.0 or 0% NaCl diets and simultaneously administered 20 p.p.m. indomethacin dissolved in the drinking water. When the rats were killed, a dose-related increase of malondialdehyde (MDA) was found in both gastric mucosa and urine, the urinary MDA levels clearly correlating with those for stomach tissue. Cell proliferation of fundic mucosa was also significantly increased in rats fed 4.0 or 2.0% NaCl-supplemented diet. Indomethacin suppressed the 4% NaCl-associated MDA increase in both gastric mucosa and urine as well as the elevation in cell proliferation. The results clearly show that administration of NaCl, a gastric tumor promoter, is associated with enhanced lipid peroxidation in the gastric mucosa.

The effects of simultaneous soybean trypsin inhibitor (SBTI) treatment on initiation of pancreatic carcinogenesis by N-nitrosobis(2-oxopropyl)amine (BOP) were investigated. Female Syrian golden hamsters were given five weekly s.c. injections of BOP at a dose of 10 mg/kg while being administered a diet containing 5% SBTI for 5 weeks (BOP + SBTI group). Two other groups of 30 animals each received the s.c. injections of BOP or the 5% SBTI diet for the same period, alone (BOP and SBTI groups respectively). Total numbers of pancreatic dysplastic lesions in hamsters of the BOP+SBTI group were significantly decreased as compared to the BOP group values, though the incidences of pancreatic adenocarcinomas were not significantly different. Atrophic changes were, however, more severe in the BOP group than in the BOP+SBTI group pancreatic exocrine tissue, showing that treatment with SBTI was effective for protection of acinar cells from carcinogen toxicity.

We investigated the effects of YM-13650, 2-(m-carboxyacetoxyphenyl) imidazo [2, 1-b] benzothiazole, on BSA-immune complex nephritis in rats and lupus nephritis in NZB/W F1 mice. In preventative experiments on immune complex nephritis in rats, YM-13650 (10 approximately 100 mg/kg, p.o.) dose-dependently inhibited the increase in urinary protein, serum cholesterol, and urea nitrogen. Histopathological observation showed striking hypercellularity and mesangial widening in nephritic control; however, glomerular injury was reduced in YM-13650-treated animals. In therapeutic study, control rats maintained high levels of urinary protein, serum cholesterol and urea nitrogen throughout the experimental period. These variables were lower in YM-13650-treated rats. In preventative experiments in lupus mice treated from 8 weeks of age, YM-13650 in comparison with the control group showed a lesser degree of proteinuria throughout the experimental period. It also significantly prolonged or tended to prolong the life span of NZB/W F1 mice compared with the control. In therapeutic experiments conducted after the onset of lupus nephritis in mice, the drug also inhibited an increase in urinary protein and tended to prolong the life span. These results show that YM-13650 has preventative and therapeutic effects on experimental nephritis in rats and mice, and it may prove valuable as an anti-nephritic drug.

In this study, blood coagulation and fibrinolytic parameters were measured in maternal blood and fetal umbilical cord blood in 200 normal pregnant women and in 46 with severe toxemia of pregnancy (Toxemia), and the relationships between fetal growth and concentrations protein C (PC), antithrombin-III (AT-III) and alpha 2-plasmin inhibitor (alpha 2-PI) were studied. 1. Significant increases in fibrin degradation products (FDP) and in plasminogen (Plg), AT-III and PC were found in maternal blood of Toxemia. A significant increase in AT-III and a decrease in alpha 2-PI and PC were observed in cord blood from these patients. 2. The platelet count (Pl) tended to be low in patients with Toxemia complicated by fetal growth retardation (IUGR). 3. Pl and fibrinogen (Fib) tended to be high in Toxemia complicated by normal fetal growth. 4. PC increased from early pregnancy, and a further increase was observed in the puerperium. 5. The PC concentration correlated with the AT-III but not with the alpha 2-PI concentration in maternal blood. 6. PC in cord blood was lower than that in maternal blood, and was correlated with AT-III and alpha 2-PI. 7. In patients with Toxemia, PC was reduced in both maternal and cord blood, and this correlated with AT-III as well as alpha 2-PI in maternal blood. 8. PC was low in Toxemia complicated by hypertension and proteinuria. These results suggest the involvement of FDP, AT-III, PC and Plg in the pathogenesis of Toxemia, and that the Pl, Fib, FDP and alpha 2-PI concentrations are related to fetal growth. Therefore, the PC and AT-III concentrations appeared to be a useful index for the blood coagulation and fibrinolysis in pregnant women and appeared to be important factors in the degree of Toxemia and IUGR.

The cerebral protective actions of a new thyrotropin releasing hormone (TRH) analogue, YM-14673, [Na-[[(S)-4-oxo-2-azetidinyl-carbonyl]-L-histidyl-L-prolinamide] dihydrate), were compared with those of CDP-choline (cerebral metabolic enhancer) and naloxone in rats rats subjected to unilateral carotid artery ligation and anoxic exposure (Levine rats). Drugs were administered intraperitoneally or orally 20, 80, and 140 min after anoxia. YM-14673 (0.03 to 1 mg/kg i.p. and 0.3 to 10 mg/kg p.o.) decreased the incidence of neurological deficits, such as hemiplegia and convulsion followed by coma and death, for 48 h after ischemia and anoxia. Both the increase in the brain water content and the degeneration of neurons in the cerebral cortex and thalamus were prevented by YM-14673 at a dose of 0.1 mg/kg (i.p.). CDP-choline (400 mg/kg i.p.), which is currently used in the therapy of cerebral vascular diseases, and naloxone (3 mg/kg i.p.) also decreased the incidence of the neurological deficits. These results suggest that YM-14673 protects Levine rats against neurological deficits, presumably by attenuating the development of brain edema and preventing neuronal damage. This compound may be useful in the therapeutic treatment of cerebral vascular diseases.

Dose-related increase of malondialdehyde (MDA) was found in both gastric mucosa and urine after 5-week administration of 4.0, 2.0, 1.0, 0.5, 0.25 or 0% NaCl supplemented diet to rats. NaCl, a gastric tumor promoter, is associated with enhanced lipid peroxidation in the gastric mucosa. The urinary MDA level was found to be a good indicator of lipid peroxidation state in the gastric mucosa, higher levels of MDA in the urine clearly correlating with data for stomach glandular tissue. In man, elevation of MDA was also observed in the urine of patients with gastric lesions such as chronic gastritis, precancerous and cancer, as well as in individuals suffering from liver and kidney disease.

The main objective of this work was to determine the influence of cigarette smoke exposure on the mechanisms which promote respiratory tumors. And another aim was the accumulation of basic data regarding the effect of cigarette smoke exposure in hamsters in the Hamburg II smoking machine. Male Syrian golden hamsters were caused to inhale cigarette smoke in the Hamburg II smoking machine. The hamsters inhaled cigarette smoke twice a day, for 9 minutes, 5 times a week. The administration period were 1,2,4,8 and 12 weeks. For each inhalation, the rotating disk was fitted with 30 cigarettes. Each puff, 35 ml in volume, was diluted seven times with room air. At the completion of administration, subjects were examined histopathologically, and lung and serum lipid peroxidation levels were also measured. Histopathological examination of the respiratory tract and alveolar epithelium disclosed no cigarette smoke-related hyperplastic lesion in any animal. And in the hamsters which inhaled cigarette smoke, "smoke cells" accumulation were observed in the alveolar space after 8 and 12 weeks exposure. Significant increase in the number of BrdU positive cells were not observed following cigarette smoke exposure, but a tendency for lung malondialdehyde (MDA) levels to increase was evident. On the other hand, serum lipid peroxide (LPO) levels showed a marked decrease in the animals exposed to cigarette smoke for 2,4 and 8 weeks in comparison with the identically handled control animals. But serum LPO levels showed a tendency to increase with cigarette smoking during all experimental periods. The above results suggested that cigarette smoking may cause a change in lipid peroxidation levels such as lung MDA and serum LPO levels.

A twenty-eight day repeated dose toxicity test of dicyclopentadiene (DCPD) was carried out in male and female F344 rats at the dose levels of 200, 40, 8 or 0 mg/kg/day. Thirty six animals of both sexes were divided into 6 groups of equal number. All groups were treated i.g. administration for 28 days daily, and two groups of them, at the dose levels of 200 and 0 mg/kg, were used for investigation of recovery. Inhibition of body weight gain was observed in the 200 mg/kg groups in both sexes and the 40 mg/kg group in male, but in female this inhibition was recovered at day 17 of the treatment. Increases in liver and adrenal gland weights, and decrease in thymus weight were noted in the 200 mg/kg groups in both sexes, and increase in kidney weight was also observed in the 200 and 40 mg/kg groups in male. On histopathological examination, hypertrophy of the adrenal cortex, and foamy cytoplasm in hepatocytes were observed in the 200 mg/kg groups of both sexes. Repair of histopathological lesions occurred within 14 days resting period. Based on these findings, it was concluded that the No Observed Effect Level of DCPD would be 8 mg/kg/day.

Rat renal calcification and stone formation were investigated using a JEOL-JSM840A scanning electron microscope (SEM) equipped with a LINK-QX200J energy dispersed X-ray detector (EDX). Male Wistar rats were treated with 100 ppm N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the drinking water or 10% NaCl in the diet for 8 weeks, and subsequently administered a dietary supplement of 0.1% ethoxyquin (EQ) for 32 weeks. An additional group received the EQ treatment alone. Calcification and stones were observed from the renal papilla to the pelvis region in all EQ treated groups. The incidence and grade of the lesion in the combined treated groups were much more greater than in the group treated with exposed to EQ alone. Ultrastructurally, microvilli on the surface of the renal papilla cells appeared degenerated or disappeared completely in the treated groups. Chemical element analysis of the renal stones revealed P and Ca to be the primary constituents. They were therefore considered to be of hydroxyapatite type.

The pathogenesis of 1,3-dinitrobenzene (1,3-DNB)-associated testicular toxicity was investigated in Sprague-Dawley rats with 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry and lanthanum-tracer methods as well as routine histopathological examination. Animals were killed at 8, 12, 24, 48 and 96 hr after a single oral administration of 1,3-DNB at a dose of 25 mg/kg. Histopathologically, severe alterations in the testes such as degenerating pachytene spermatocytes and giant cell formation were observed by 24 hr. Immunohistochemical analysis revealed no differences in the distribution of BrdU-positive cells between treated and control rats throughout the experiment. Thus it was concluded that 1,3-DNB exerted no effects on DNA synthesis in spermatogonia and preleptotene spermatocytes. Using the lanthanum-tracer method, it was shown that although lanthanum could penetrate the intercellular space from the basement membrane, the tight junction, consisting of fusions of contiguous Sertoli cell membranes, prevented further diffusion in both control rats and those killed at 8 hr after dosing. On the other hand, at 24 hr after dosing, lanthanum penetrated into the adluminal compartment beyond the tight junctions, thus demonstrating loss of integrity of the blood-testis barrier. The results suggested that the Sertoli cell is the primary target of 1,3-DNB testicular toxicity.

The effects of dietary high fat on 4-nitroquinoline 1-oxide (4NQO)-induced lung tumorigenesis were investigated in male ICR mice. Two groups of mice were initially given a single subcutaneous injection of 4NQO at a dose of 15 mg/kg and, thereafter, fed either 20% corn oil-supplemented diet or a standard basal diet. Two further groups were maintained on the high fat diet or standard diet without administration of 4NQO. Mice were killed at weeks 15, 18 and 25 and the incidence of lung tumors at each time point was found to be significantly increased in the 4NQO/high fat diet group as compared to the 4NQO/standard diet group in terms of both incidence of tumor-bearing mice and the number of lesions per mouse. The results thus indicate that dietary high fat can enhance 4NQO-induced lung tumorigenesis in mice.

Glyoxal and methylglyoxal were tested for tumor-promoting potential in a two-stage stomach carcinogenesis model. Male outbred Wistar rats were initially given N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the drinking water (100 mg/l) along with a 10% sodium chloride dietary supplement for 8 weeks. Thereafter, they were returned to basal diet and maintained on drinking water containing no addition or either 0.5% glyoxal or 0.25% methylglyoxal for 32 weeks and then killed for necropsy and histological examination at week 40. Glyoxal treatment significantly increased the incidence of adenocarcinomas in the pylorus of the glandular stomach of rats pretreated with MNNG and sodium chloride. Furthermore, although methylglyoxal did not enhance the development of adenocarcinomas, the incidence of hyperplasias in the pylorus was significantly increased. The results indicate that glyoxal exerts tumor promoting activity on rat glandular stomach carcinogenesis and that methylglyoxal might also have promoting potential.