Innervation of Extrahepatic Biliary Tract,With Special Reference to the Direct Bidirectional Neural Connections of the Gall Bladder,Sphincter of Oddi and Duodenum in Suncus murinus,in Whole‐Mount Immunohistochemical Study

Sphincter of Oddi dysfunction is one of the most important symptoms in post‐cholecystectomy syndrome. Using either electrical or mechanical stimulation and retrogradely transported neuronal dyes, it has been demonstrated that there are direct neural pathways connecting gall bladder and the sphincter of Oddi in the Australian opossum and the golden hamster. In the present study, we employed whole‐mount immunohistochemistry staining to observe and verify that there are two different plexuses of the extrahepatic biliary tract in Suncus murinus. One, named Pathway One, showed a fine, irregular but dense network plexus that ran adhesively and resided on/in the extrahepatic biliary tract wall, and the plexus extended into the intrahepatic area. On the other hand, named Pathway Two, exhibiting simple, thicker and straight neural bundles, ran parallel to the surface of the extrahepatic biliary tract and passed between the gall bladder and duodenum, but did not give off any branches to the liver. Pathway Two was considered to involve direct bidirectional neural connections between the duodenum and the biliary tract system. For the first time, morphologically, we demonstrated direct neural connections between gall bladder and duodenum in S. murinus. Malfunction of the sphincter of Oddi may be caused by injury of the direct neural pathways between gall bladder and duodenum by cholecystectomy. From the viewpoint of preserving the function of the major duodenal papilla and common bile duct, we emphasize the importance of avoiding kocherization of the common bile duct so as to preserve the direct neural connections between gall bladder and sphincter of Oddi.     

Preparation of heavy meromyosin from the autolyzed squid mantle muscle homogenate

ABSTRACT:   Incubation of squid mantle muscle homogenate caused a selective cleavage of myosin into heavy meromyosin (HMM) and light meromyosin (LMM). HMM was isolated from the incubated homogenate by using ammonium sulfate fractionation. The purified HMM retained two types of light chain components. Its Mg²⁺-ATPase activity with or without F-actin showed a Ca-sensitivity. HMM was cleaved into subfragment-1 and subfragment-2 upon chymotryptic digestion with or without Ca²⁺, possessing different light chain composition. Two types of light chain component were kept intact when digested in the presence of Ca²⁺. Ca²⁺ stabilized HMM especially in a bound form to F-actin.     

Myosin denaturation in heated myofibrils of scallop adductor muscle

The thermal inactivation of Ca²⁺ ATPase of scallop myofibrils (0.1 M KCl, pH 7.5) was found to be unaffected by the presence of Ca²⁺. Monomeric myosin content and salt solubility decreased much faster than Ca²⁺ ATPase inactivation in both Ca and EDTA media, which was well explained by faster denaturation of the rod portion than subfragment-1 of myosin. In contrast, when the myofibrils were heated at 0.5 M KCl, a slow decrease in salt solubility was observed, which was also explained by slow denaturation of the rod portion of myosin. Myofibrils from scallop smooth muscle showed the same denaturation pattern as those from adductor muscle. These results show that mollusk myosin is not always stabilized by Ca²⁺.     

Histopathological Changes in the Pancreas from a Spontaneous Hyperglycemic Cynomolgus Monkey

Morphological and immunohistochemical examinations were carried out on the pancreas of a hyperglycemic 5-year-old male cynomolgus monkey. Body weight gradually decreased from 6 months before termination, accompanying a slight reduction in food consumption and anorexia for the last 2 days. The blood glucose level was markedly elevated when examined at termination. Histopathologically, in the exocrine pancreas, diffuse hyperplasia of centroacinar and intercalated duct cells and diffuse atrophy of acinar cells with sporadic apoptosis were observed, although most centroacinar and intercalated duct cells were proliferating cell nuclear antigen (PCNA)-positive in both the present case and age-matched control animals. In the endocrine pancreas, the islets tended to be hypertrophic, with an increase in insulin-positive cells in comparison with the age-matched control animals. PCNA-positive cells also tended to increase in the islets, although positive cells for phospho-histone H3, a marker for mitotic cells, were not detected in the endocrine and exocrine pancreas. Moreover, neither inflammation nor amyloidosis was noted in the islets. In conclusion, the present case probably suffered from early-stage type 2 diabetes mellitus, and it provides fundamental information concerning pancreatic histopathology under insulin-related derangement in monkeys.     

Occurrence of 7,7′-biphyscion in Japanese soils

Abstract

A variety of higher plants and microorganisms, especially soil fungi, form anthra-quinone pigments (Thomson 1987) and, although many of these compounds are biologically active as antibiotics, chelating agents and possible contributors of humic substance formation (Kumada 1987), little information is available about their distribution and role in soil systems.     

AKD-2023: A novel miticide. Biological activity and mode of action

AKD-2023, 3-dodecyl-1,4-dihydro-1,4-dioxo-2-naphthyl acetate (proposed common name acequinocyl) is a novel miticide now under commercial development. It has outstanding miticidal activity against economically important spider mites with the new mode of action of inhibition of mitochondrial electron transfer at complex III.     

Satellite Analysis of Volcanic Clouds and Transport of Acidic Substances from Mt. Aso and Mt. Sakurajima

The satellite images of volcanic clouds in Kyushu, Japan during September–November 1989 were studied in connection with the mountain site measurement of atmospheric qualities at Unzen-Nodake and the SO₂ concentration data at Aso Volcano Museum. The images strongly indicate that many high concentration events of SO₂ were the results of the long-range transport of volcanic gas from Mt. Aso and Mt. Sakurajima to these stations. Brief comments on the 2000 eruption of Miyake-jima volcano are added.     

Comparison and characterization of biosorption by Weissella viridescens MYU 205 of periodic group 12 metal ions

Because heavy metals cause various health hazards, we studied biosorption by Weissella viridescens MYU 205. MYU 205 showed high biosorption for Cd (II) and Hg (II) and was low for Zn (II). The Hg (II) biosorption rate was high at about 80%. Different biosorptions were shown for each metal after successive incubation. About 20% of the Zn (II) biosorption was observed after 3 h. Cd (II) biosorption increased in a time‐dependent manner until 3 h, then gradually decreased. Hg (II) was immediately sorbed at 79.6 ± 4.7% and decreased at 3 h to 52.9 ± 2.6%, and then gradually increased to 77.8 ± 3.6%. Using heat‐killed cells, the rate of biosorption of Zn (II) and Cd (II) decreased whereas Hg (II) tended to increase. The metal resistance was high, that is Zn (II) > Cd (II) > Hg (II); while the affinity was opposite where MYU 205 showed high affinity to Hg (II) and low affinity to Zn (II). Our data shows lactic acid bacteria may be powerful heavy metal sorbents for detoxification.     

Involvement of anteroventral periventricular metastin/kisspeptin neurons in estrogen positive feedback action on luteinizing hormone release in female rats

Metastin/kisspeptin, the KiSS-1 gene product, has been identified as an endogenous ligand of GPR54 that reportedly regulates GnRH/LH surges and estrous cyclicity in female rats. The aim of the present study was to determine if metastin/kisspeptin neurons are a target of estrogen positive feedback to induce GnRH/LH surges. We demonstrated that preoptic area (POA) infusion of the anti-rat metastin/kisspeptin monoclonal antibody blocked the estrogen-induced LH surge, indicating that endogenous metastin/kisspeptin released around the POA mediates the estrogen positive feedback effect on GnRH/LH release. Metastin/kisspeptin neurons in the anteroventral periventricular nucleus (AVPV) may be responsible for mediating the feedback effect because the percentage of c-Fos-expressing KiSS-1 mRNA-positive cells to total KiSS-1 mRNA-positive cells was significantly higher in the afternoon than in the morning in the anteroventral periventricular nucleus (AVPV) of high estradiol (E(2))-treated females. The percentage of c-Fos-expressing metastin/kisspeptin neurons was not different between the afternoon and morning in the arcuate nucleus (ARC). Most of the KiSS-1 mRNA expressing cells contain ERalpha immunoreactivity in the AVPV and ARC. In addition, AVPV KiSS-1 mRNA expressions were highest in the proestrous afternoon and lowest in the diestrus 1 in females and were increased by estrogen treatment in ovariectomized animals. On the other hand, the ARC KiSS-1 mRNA expressions were highest at diestrus 2 and lowest at proestrous afternoon and were increased by ovariectomy and decreased by high estrogen treatment. Males lacking the surge mode of GnRH/LH release showed no obvious cluster of metastin/kisspeptin-immunoreactive neurons in the AVPV when compared with high E(2)-treated females, which showed a much greater density of these neurons. Taken together, the present study demonstrates that the AVPV metastin/kisspeptin neurons are a target of estrogen positive feedback to induce GnRH/LH surges in female rats.