Seven new bibenzyls and a dihydrochalcone from Radula variabilis

Six new bibenzyls have been isolated from the liverwort, Radula variabilis and their structures have been established by chemical and spectral evidence. In addition, a new dihydrochalcone and a new bibenzy] have been isolated as their methyl ethers. Except for two of the bibenzyls, the present compounds have a unique seven-membered heterocyclic ring and they are the first members of a new group of natural product.     

Odorant receptor expression in the mouse cerebral cortex

Mammalian odorant receptors have been known to be involved not only in odorant detection but also in neuronal development of olfactory sensory neurons. We have examined a possibility of odorant receptor expression in nonolfactory neurons in the mouse. Mouse odorant receptors (M71, C6, and OR3), two of which were already shown to be functionally activated by odorants in heterologous systems, were detected by polymerase chain reactions (PCRs) from the cerebral cortex but not from other brain tissues. Degenerate PCR further suggested that other odorant receptors were also expressed in the mouse cerebral cortex. One of these receptors showed high sequence-match with a putative chick odorant receptor OR7 transiently expressed in the notochord during development. In situ hybridization detected signals for M71 and C6 receptors in the layer II cortical pyramidal neurons located in the occipital pole. In the M71-IRES-tauLacZ mouse, in which M71 expression was genetically marked with tauLacZ, X-gal staining signals were mostly localized in the layer II neurons in the occipital pole, being consistent with the in situ hybridization result. Fluorescent immunohistochemistry using anti-beta-galactosidase antibody further detected the tauLacZ signals in the same cells. X-gal staining began at P3, peaked at P8, and continued to adults, although signals gradually decreased. These data showed that at least a few odorant receptors are expressed not only in olfactory sensory neurons but also in pyramidal neurons in the cerebral cortex, possibly playing an important role either in chemical detection of exogenous or endogenous ligands or in a developmental process such as axon guidance and target recognition.     

Virus-mediated transduction of apolipoprotein E (ApoE)-sendai develops lipoprotein glomerulopathy in ApoE-deficient mice

Lipoprotein glomerulopathy (LPG) is a unique renal disease characterized by thrombus-like substances in markedly dilated glomerular capillaries, dysbetalipoproteinemia, and elevated plasma concentrations of apoE. Recent studies identified several apoE mutations in patients with LPG, including apoE2(R145P) Sendai (apoE-Sendai). Virus-mediated transduction of apoE-Sendai in apoE-deficient hypercholesterolemic mice resulted in insufficient correction of hypercholesterolemia and a marked and temporal induction of plasma triglyceride levels. In vitro binding studies showed that apoE-Sendai has a reduced affinity for the low density lipoprotein receptor, suggesting that dysbetalipoproteinemia in LPG is caused by the apoE mutation. Furthermore, histological examination revealed marked intraglomerular depositions of apoE-containing lipoproteins in mice injected with apoE-Sendai virus. These LPG-like depositions were detected 6 days after virus injection and were sustained for at least 60 days. Our results demonstrated that apoE-Sendai is an etiological cause of LPG.     

Chum salmon trypsin-catalyzed preferential formation of peptides containing D-amino acid

Summary. Chum salmon trypsin-catalyzed peptide synthesis has been studied by using nine series of "inverse substrates," i.e., p-amidinophenyl, p- and m-guanidinophenyl, p- and m-(guanidinomethyl)phenyl, and four position isomers of guanidinonaphthyl esters derived from N ^α -(tert-butyloxycarbonyl)amino acid as acyl donor components. They were found to couple with an acyl acceptor such as l-alanine p-nitroanilide to produce dipeptide in the presence of trypsin. All substrates tested in this study undergo less enantioselective coupling reaction, and the coupling product was the favorably obtained d-series rather than l-series (in the present case; N ^α -Boc-d-Ala and N ^α -Boc-l-Ala). The optimum condition for the coupling reaction was studied by changing the organic solvent, buffer solution, pH, and acyl acceptor concentration. It was found that the enzymatic hydrolysis of the resulting product was negligible. Received August 10, 2000 Accepted December 2, 2000     

Partial hepatectomy of marmoset: clinical and pathological effects and utility in microsomal enzyme analysis.

Liver biopsy based on a partial hepatectomy technique (shearing) was performed in 10 common marmosets (Callithrix jacchus). This is a preliminary study to evaluate the effects of drugs on hepatic microsomal enzymes: cytochrome P-450 and T4 uridine diphosphate glucuronyl transferase (T4-UDPGT), by comparing post-treatment values with pre-treatment values individually with a limited number of animals. The effects of the biopsy on clinical findings and liver pathology were evaluated during the first 5 post-surgical weeks. Although the plasma aspartate aminotransferase (AST) activities tended to decrease from 1 to 4 weeks post-surgery, no abnormality was noted in clinical sign, body weight, the hematocrit value or other blood chemical values. At necropsy, adhesion of the sheared site of the liver to the parietal peritoneum or the small intestine was evident in 2 of the 4 marmosets. Microscopic examination revealed focal fibrosis in the liver, but it was localized around the sheared site. Based on the above results, it was concluded that liver biopsy must be performed more than one month before administration of the drug to be tested. The biopsy samples and the whole liver samples obtained at autopsy were subjected to analysis of microsomal protein content, cytochrome P-450 content and T4-UDPGT activity. In comparison with the values from the whole liver samples, those from the biopsy samples showed no significant difference. Furthermore, there was a significant correlation rather than difference between matched values. This suggested that partial hepatectomy is a useful method for obtaining pretreatment values in liver biochemistry to evaluate the effects of drug-treatment in individual animals.     

Ocular Surface Displacement with and without Contact Lenses during Non-Contact Tonometry

Purpose

To evaluate the displacement of the central ocular surface during non-contact tonometry with and without soft contact lenses and determine the factors associated with the displacement of the central ocular surface and intraocular pressure (IOP) reading changes caused by wearing soft contact lenses (CLs).

Methods

One eye each in 21 subjects was studied. The cornea was photographed using a high-speed camera at 5,000 frames/sec during non-contact tonometry without contact lenses (NCL), with -5.0 diopters (D), -0.5 D and +5.0 D CL. The displacement of the ocular surface and the factors affecting displacement at the IOP reading and maximum displacement time were investigated.

Results

The IOP readings while wearing +5 D CL were significantly higher than those obtained while wearing -5 D CL. The ocular surface displacement between +5 D CL and other groups were significantly different. A significant positive correlation was found between the ocular surface displacement of subjects at the IOP reading time and the IOP obtained with the non-contact tonometer. A significant negative correlation was found between the ocular surface curvature and the IOP obtained using the non-contact tonometer. The radius of curvature of the ocular surface affected the displacement during the IOP reading and maximum displacement time.

Conclusions

Our results indicate that soft contact lens use changes the ocular surface behavior and IOP readings during non-contact tonometry. The radius of curvature of the eye affects the ocular surface displacement and IOP readings in this situation.     

An Arabidopsis E3 ligase, SHOOT GRAVITROPISM9, modulates the interaction between statoliths and F-actin in gravity sensing

Higher plants use the sedimentation of amyloplasts in statocytes as statolith to sense the direction of gravity during gravitropism. In Arabidopsis thaliana inflorescence stem statocyte, amyloplasts are in complex movement; some show jumping-like saltatory movement and some tend to sediment toward the gravity direction. Here, we report that a RING-type E3 ligase SHOOT GRAVITROPISM9 (SGR9) localized to amyloplasts modulates amyloplast dynamics. In the sgr9 mutant, which exhibits reduced gravitropism, amyloplasts did not sediment but exhibited increased saltatory movement. Amyloplasts sometimes formed a cluster that is abnormally entangled with actin filaments (AFs) in sgr9. By contrast, in the fiz1 mutant, an ACT8 semidominant mutant that induces fragmentation of AFs, amyloplasts, lost saltatory movement and sedimented with nearly statically. Both treatment with Latrunculin B, an inhibitor of AF polymerization, and the fiz1 mutation rescued the gravitropic defect of sgr9. In addition, fiz1 decreased saltatory movement and induced amyloplast sedimentation even in sgr9. Our results suggest that amyloplasts are in equilibrium between sedimentation and saltatory movement in wild-type endodermal cells. Furthermore, this equilibrium is the result of the interaction between amyloplasts and AFs modulated by the SGR9. SGR9 may promote detachment of amyloplasts from AFs, allowing the amyloplasts to sediment in the AFs-dependent equilibrium of amyloplast dynamics.     

Human hepatocyte growth factor promotes functional recovery in primates after spinal cord injury

Many therapeutic interventions for spinal cord injury (SCI) using neurotrophic factors have focused on reducing the area damaged by secondary, post-injury degeneration, to promote functional recovery. Hepatocyte growth factor (HGF), which is a potent mitogen for mature hepatocytes and a mediator of the inflammatory responses to tissue injury, was recently highlighted as a potent neurotrophic factor in the central nervous system. We previously reported that introducing exogenous HGF into the injured rodent spinal cord using a herpes simplex virus-1 vector significantly reduces the area of damaged tissue and promotes functional recovery. However, that study did not examine the therapeutic effects of administering HGF after injury, which is the most critical issue for clinical application. To translate this strategy to human treatment, we induced a contusive cervical SCI in the common marmoset, a primate, and then administered recombinant human HGF (rhHGF) intrathecally. Motor function was assessed using an original open field scoring system focusing on manual function, including reach-and-grasp performance and hand placement in walking. The intrathecal rhHGF preserved the corticospinal fibers and myelinated areas, thereby promoting functional recovery. In vivo magnetic resonance imaging showed significant preservation of the intact spinal cord parenchyma. rhHGF-treatment did not give rise to an abnormal outgrowth of calcitonin gene related peptide positive fibers compared to the control group, indicating that this treatment did not induce or exacerbate allodynia. This is the first study to report the efficacy of rhHGF for treating SCI in non-human primates. In addition, this is the first presentation of a novel scale for assessing neurological motor performance in non-human primates after contusive cervical SCI.