Improved in vivo antitumor efficacy and reduced systemic toxicity of carboxymethylpullulan-peptide-doxorubicin conjugates

The antitumor efficacy of the conjugate of doxorubicin (DXR) and carboxymethylpullulan (CMPul) with Phe-Gly spacer (CMPul-FG-DXR) was evaluated using murine tumor models and compared with that of DXR. The conjugate exhibited higher antitumor efficacy against Lewis lung carcinoma than DXR. Complete tumor regression followed by long-term tumor-free survival was frequently observed when CMPul-FG-DXR was administered i.v. three times at a dose equivalent to 10 mg / kg of DXR. The superior survival as well as anti-metastatic effect of CMPul-FG-DXR in comparison with DXR was also demonstrated with the M5076 murine reticulosarcoma model. Body weight loss in mice treated with the conjugate was less than that in the DXR-treated group, indicating lower systemic toxicity of CMPul-FG-DXR. Simply mixing CMPul with DXR did not enhance the antitumor activity of DXR, showing that the conjugation of DXR with CMPul is necessary for improved antitumor activity. However, no enhanced antitumor efficacy of the conjugates was observed against a non-solid tumor model such as P388 leukemia. In summary, improved antitumor efficacy with reduced systemic toxicity of CMPul-FG-DXR was demonstrated in the present study. CMPul-FG-DXR may be useful as a cancer chemotherapy agent against solid tumors and metastases.

A method for measuring endpoint stiffness during multi-joint arm movements

Current methods for measuring stiffness during human arm movements are either limited to one-joint motions, or lead to systematic errors. The technique presented here enables a simple, accurate and unbiased measurement of endpoint stiffness during multi-joint movements. Using a computer-controlled mechanical interface, the hand is displaced relative to a prediction of the undisturbed trajectory. Stiffness is then computed as the ratio of restoring force to displacement amplitude. Because of the accuracy of the prediction (< 1 cm error after 200 ms) and the quality of the implementation, the movement is not disrupted by the perturbation. This technique requires only 13 as many trials to identify stiffness as the method of Gomi and Kawato (1997, Biological Cybernetics 76, 163-171) and may, therefore, be used to investigate the evolution of stiffness during motor adaptation.

Role of the gynoecium in natural senescence of carnation (Dianthus caryophyllus L.) flowers

Although the role of the gynoecium in natural senescence of the carnation flower has long been suggested, it has remained a matter of dispute because petal senescence in the cut carnation flower was not delayed by the removal of gynoecium. In this study, the gynoecium was snapped off by hand, in contrast to previous investigations where removal was achieved by forceps or scissors. The removal of the gynoecium by hand prevented the onset of ethylene production and prolonged the vase life of the flower, demonstrating a decisive role of the gynoecium in controlling natural senescence of the carnation flower. Abscisic acid (ABA) and indole-3-acetic acid (IAA), which induced ethylene production and accelerated petal senescence in carnation flowers, did not stimulate ethylene production in the flowers with gynoecia removed (-Gyn flowers). Application of 1-aminocyclopropane-1-carboxylate (ACC), the ethylene precursor, induced substantial ethylene production and petal wilting in the flowers with gynoecia left intact, but was less effective at stimulating ethylene production in the -Gyn flowers and negligible petal in-rolling was observed. Exogenous ethylene induced autocatalytic production of the gas and petal wilting in the -Gyn flowers. These results indicated that ethylene generated in the gynoecium triggers the onset of ethylene production in the petals of carnation during natural senescence.

[Current activities of the Japan Poison Information Center and Information Network for Poisoning via the Internet]

The current activities of the Japan Poison Information Center and poison information originally collected by it are explained. The Information Network for Poisoning via the Internet in Japan is also introduced, including some useful related sites based abroad.

Tactile functions of mechanoreceptive afferents innervating the hand

Four types of mechanoreceptive afferents innervate the glabrous skin of the hand. Evidence from more than three decades of combined psychophysical and neurophysiological research supports the idea that each afferent type serves a distinctly different sensory function and that these functions explain most of tactual perceptual function. The available evidence supports the following hypotheses: (1) The slowly adapting type 1 system provides the information on which form and texture perception are based. (2) The cutaneous rapidly adapting system provides information about minute skin motion and, thereby, plays a critical role in grip control. (3) The Pacinian system is responsible for the detection and perception of distant events by vibrations transmitted through objects, probes, and tools held in the hand. (4) The slowly adapting type 2 system provides information for the perception of hand conformation and for the perception of forces acting on the hand. The authors review the evidence on which these hypotheses are based. They also review the role of proprioceptive afferents in the perception of hand conformation because they appear to play a significant role along with cutaneous afferents.

A new method for quantitative analysis of the mouse T-cell receptor V region repertoires: comparison of repertoires among strains

We developed an adaptor ligation PCR-based microplate hybridization assay (MHA) to analyze the repertoires of mouse T-cell receptor (TCR) alpha- and beta-chain variable regions (TCRAV and TCRBV). RNA is transcribed to cDNA and an adaptor is ligated to the 5' end of the cDNA, which is then used as a template for PCR with an adaptor-specific 3' primer and a constant region-specific 5' primer. After hybridization of PCR products with TCRAV-and TCRBV-specific probes on the microplate, quantitative ELISA was carried out. The entire TCRAV or TCRBV repertoires could be analyzed using a single 96-well plate in triplicate and completed in less than 4 h. The assay results demonstrated the high level of specificity and reproducibility of this method. Furthermore, MHA results correlated well with those of fluorescence-activated cell sorting. This method may provide important information about various T-cell-associated diseases including autoimmune disease. The influence of the MHC on mouse TCR repertoires was next studied using the newly developed mouse TCRAV and TCRBV repertoire assay. The analysis in six strains showed no significant correlation between MHC haplotypes and TCRAV and TCRBV repertoires. However, large differences among strains was observed in TCRBV, but not in TCRAV repertoires. There were also large differences within same strain in TCRBV, but not in TCRAV repertoires, indicating differences in individuals independent of genetic factors. These data suggest that TCRBV repertoires are more susceptible than TCRAV repertoires not only to genetic factors but also some environmental factors.

[Long-term results of right ventricular outflow reconstruction with valved conduit]

Twenty-nine patients who underwent right ventricular outflow tract reconstruction using a valved conduit 37 times and survived surgery, were reviewed in this study. Hancock, Ionescu-Shiley, Carpentier-Edwards and Polystan was used for RVOTR. Freedom from reoperation rates of Hancock, Ionescu-Shiley and Carpentier-Edwardsat at five and ten years after surgery were 100%, 85.7%, 89.2% and 75%, 28.6%, 89.2%, respectively. The freedom from reoperation rates of Hancock and Carpentier-Edwards were significantly higher than that of Ionescu-Shiley. In conclusion, the freedom from reoperation rate at ten years was high for both Hancock and Carpentier-Edwards.

Suppression of type II collagen-induced arthritis by a new isocoumarin, NM-3

The anti-arthritic effect of NM-3, a new isocoumarin, was examined using a type II collagen-induced arthritis model for human rheumatoid arthritis in DBA/1J mice. NM-3 by oral administration suppressed dose-dependently (2-20 mg/kg/day) not only macroscopic changes such as erythema and swelling of limbs but also histopathologic changes and radiographic changes such as bone lesions. The efficacy of NM-3 was greater than those of disease-modifying anti-rheumatoid drugs (DMARDs), auranofin (40 mg/kg/day) and bucillamine (10 mg/kg/day). NM-3 failed to suppress carageenan-induced edema and to inhibit the activities of inflammation-related enzymes including cyclooxygenase-1 and -2, 5-lipoxygenase and phospholipase A2, suggesting that the mode of anti-arthritic action of NM-3 may be different from those of non-steroidal anti-inflammatory agents (NSAIDs). Since NM-3 inhibits angiogenesis in a mouse dorsal air-sac model, the observed anti-arthritic effect of NM-3 might be partly attributed to the antiangiogenic activity. Thus, NM-3 is a potential orally active therapeutic agent for the treatment of human rheumatoid arthritis.

Investigation of the possible role of sialic acid in calcium oxalate urolithiasis

OBJECTIVE

It is considered that sialic acid in urine comprises two different types of sialic acid, that is, the free sialic acid and the bound one which exists as a basic component of urinary macromolecules. The present studies were performed to clarify the role of sialic acid in urine and compare the excretion and concentrations of sialic acid in urine between calcium oxalate (CaOx) stone formers and healthy subjects.

METHODS

First, we prepared the crystal surface binding substances from whole human urine. The crystal surface binding substances were digested with sialidase and both the inhibitory activity on CaOx crystal growth and concentrations of sialic acid before and after sialidase digestion were measured. The inhibitory activity of free sialic acid in ultrafiltered urine was also measured. The excretion and concentration of sialic acid in urine from patients with CaOx urolithiasis and healthy controls were determined and compared.

RESULTS

The inhibitory activity of crystal surface binding substances on CaOx crystal growth did not show any significant difference before and after sialidase digestion. The free sialic acid had also no effect on CaOx crystal growth. There was no statistically significant difference between CaOx stone formers and healthy controls on the excretion and concentration of sialic acid in urine. The free:bound sialic acid ratio in urine was considered 1:0.97 and 1:1.33 for healthy controls and CaOx stone formers respectively (p = NS).

CONCLUSIONS

It is suggested that neither the free sialic acid nor the bound one in urine has a significant inhibitory effect on CaOx crystal growth.

Laparoscopic adrenalectomy. Comparison of the transperitoneal and retroperitoneal approach

OBJECTIVES

The efficacy of transperitoneal (TP) and retroperitoneal (RP) laparoscopic adrenalectomy was compared.

METHODS

Twenty-nine patients (male: 13; female: 16) with benign adrenal tumor were evaluated in this study. Seventeen were treated with the TP, and 12 with the RP approach.

RESULTS

Convalescence for the TP group took longer than that for the RP group and postoperative pain was stronger for the TP than the RP group, although the difference was not significant. In addition, the amount of blood loss was larger for the TP than the RP group. When the cases were divided according to site of disease, the operating time for the right side was 351 min for the TP group and 347 min for the RP group, while that for the left side was 528 min for the TP group and 267 min for the RP group.

CONCLUSIONS

Therefore, we recently prefer the RP approach for left adrenalectomy, but consider either approach suitable for the right side. The reason for this preference is that shortening the operating time is most important, also in the case of laparoscopic adrenalectomy because of the resulting reduced blood loss and the patients' early convalescence.

Centrosomal kinases, HsAIRK1 and HsAIRK3, are overexpressed in primary colorectal cancers

Members of the recently identified family of Homo sapiens Aurora / Ipl1-related kinases (HsAIRKs), homologous to chromosome segregation kinases, fly Aurora and yeast Ipl1, are highly expressed during M phase, and have been suggested to regulate centrosome function, chromosome segregation, and cytokinesis. In the present study, immunohistochemical analyses were performed of HsAIRK1 and HsAIRK3 expression in 78 primary colorectal cancers and 36 colorectal adenomas as well as 15 normal colorectal specimens. In normal colon mucosa, some crypt cells showed weak positive staining in 10 and 12 out of 15 cases for HsAIRK1 and HsAIRK3, respectively, the remaining cases being negative. Elevated expression of HsAIRK1 was observed in 53 (67.9%) of the colorectal cancers, and of HsAIRK3 in 40 (51.3%). Furthermore, colorectal adenomas showed high expression of HsAIRK1 and HsAIRK3 in 11 (30.6%) and 7 (19.4%) cases, respectively, thus being intermediate between colorectal cancers and normal colorectal mucosa. Interestingly, HsAIRK1 overexpression was significantly associated with pT (primary tumor invasion) and p53 accumulation in colorectal cancers. There was no significant correlation between proliferating cell nuclear antigen-labeling index (PCNA-LI) and the levels of these proteins. The results suggest that overexpression of HsAIRK1 and HsAIRK3 might be involved in tumorigenesis and / or progression of colorectal cancers.

Contribution of OX40/OX40 ligand interaction to the pathogenesis of rheumatoid arthritis

OX40 ligand (OX40L) and OX40 (CD134) are a pair of cell surface molecules belonging to the TNF/TNF receptor family. Interaction of OX40L with its receptor OX40 is thought to be important in T cell activation through T cell/antigen-presenting cell interaction. However, involvement of these molecules in the pathogenesis of rheumatoid arthritis (RA) remains unclear. To explore the contribution of OX40/OX40L interaction to the pathogenesis of RA in vivo, we evaluated the effect of a neutralizing anti-OX40L monoclonal antibody (mAb) on the development of collagen-induced arthritis (CIA) in DBA/1 mice as an animal model for RA. Administration of anti-OX40L mAb into type II collagen (CII) -immunized DBA/1 mice dramatically ameliorated the disease severity. In vivo treatment with anti-OX40L mAb did not inhibit the expansion of CII-reactive T cells, but suppressed IFN-gamma and anti-CII IgG2a production. Therefore, OX40/OX40L interaction appears to play a critical role in the development of CIA by enhancing Th1-type autoimmune response. In addition, T lymphocytes in synovial fluid and synovial tissue from RA patients expressed OX40, while OX40L was expressed on sublining cells in synovial tissue. These results indicate that OX40/OX40L interaction may play a critical role in the development of RA.

N-methyl-D-aspartate receptor subtype 2C is not involved in circadian oscillation or photoic entrainment of the biological clock in mice

Ishida et al. [1994: Neurosci Lett 166: 211-215] reported the circadian change of N-methyl-D-aspartate (NMDA) receptor subtype 2C mRNA and photic induction of this receptor's mRNA in the suprachiasmatic nucleus (SCN). Therefore, we investigated the role of NMDA receptor subtypes in the biological clock using NMDA receptor 2A (NR2A)- or 2C (NR2C)-deficient mice. However, NR2C-/- mice showed normal light-dark (LD)-entrained locomotor activity rhythms and free-running rhythms under constant darkness and also exhibited normal reentrainment to 6-hr LD shifts and phase delays with single light pulses. Thus, present results demonstrated no significant NR2C contribution to circadian oscillation and photic entrainment, even though expression of NR2C mRNA was highly observed in the SCN. On the other hand, the period of the free-running activity rhythm in NR2A-/- mice but not NR2C-/- mice was slightly longer than that in wild-type mice in spite of low expression of NR2A in the SCN. Furthermore, reentrainment to an LD advance in NR2A-/- mice was slower under low-intensity light conditions. Thus, we suggest that NR2A plays a role in determining the behavioral state that affects the circadian rhythm. In order to elucidate the role of NR2A and NR2C in the SCN, we examined NMDA-induced Ca(2+) elevations in the SCN of mutant mice using a Ca(2+) imaging method. A partial reduction in Ca(2+) elevation was observed in both NR2A-/- and NR2C-/- mice when high concentrations (100 or 300 microM) of NMDA were applied. The present results suggest that NR2A plays a weak role in oscillation or entrainment of the biological clock, and that NR2C does not participate in the functions of circadian oscillation and light entrainment.

A Ca(2+) channel blocker-like effect of dehydrocurdione on rodent intestinal and vascular smooth muscle

Effects of dehydrocurdione, a zedoary-derived sesquiterpene, on smooth muscle were investigated by recording the mechanical activity of intestines and aorta from guinea pigs and rats. Dehydrocurdione (0.1-3 mM) induced a sustained relaxation of rat duodenum and inhibited spontaneous motility. Dehydrocurdione (0.1-1 mM) inhibited the contractile response of guinea pig ileum induced by acetylcholine (0.01-10 microM), histamine (0.03-10 microM) and substance P (0.1-30 nM) in a non-competitive manner. Acetylcholine (0.5 microM) elicited a transient contraction followed by a sustained contraction of guinea pig ileum, and dehydrocurdione pretreatment inhibited the sustained component, which depends on Ca(2+) entry from the extracellular space. The high K(+)-induced contraction of rat aortic ring is reported to be blocked by Ca(2+) channel blockers, while the norepinephrine-induced contraction includes a Ca(2+) channel blocker-resistant component. Dehydrocurdione (1 mM) blocked the high K(+) (60 mM)-induced contraction of rat aortic ring by 81%, while it inhibited the norepinephrine (1 microM)-induced contraction by only 28%. Dehydrocurdione (1 mM) significantly reduced the high K(+)-stimulated increase in cytosolic Ca(2+) level of Fura-2-loaded mesenteric artery from rats. These results suggest that the inhibitory effects of dehydrocurdione on intestinal and vascular smooth muscle are mediated by blockade of Ca(2+) entry from the extracellular space.

Expression of genes responsible for ethylene production and wilting are differently regulated in carnation (Dianthus caryophyllus L.) petals

Carnation petals exhibit autocatalytic ethylene production and wilting during senescence. The autocatalytic ethylene production is caused by the expression of 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase genes, whereas the wilting of petals is related to the expression of the cysteine proteinase (CPase) gene. So far, it has been believed that the ethylene production and wilting are regulated in concert in senescing carnation petals, since the two events occurred closely in parallel with time. In the present study, we investigated the expression of these genes in petals of a transgenic carnation harboring a sense ACC oxidase transgene and in petals of carnation flowers treated with 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS). In petals of the transgenic carnation flowers, treatment with exogenous ethylene caused accumulation of the transcript for CPase and in-rolling (wilting), whereas it caused no or little accumulation of the transcripts for ACC oxidase and ACC synthase and negligible ethylene production. In petals of the flowers treated with DPSS, the transcripts for ACC synthase and ACC oxidase were accumulated, but no significant change in the level of the transcript for CPase was observed. These results suggest that the expression of ACC synthase and ACC oxidase genes, which leads to ethylene production, is differentially regulated from the expression of CPase, which leads to wilting, in carnation petals.

Genetic risk factors for coronary artery spasm: significance of endothelial nitric oxide synthase gene T-786-->C and missense Glu298Asp variants

BACKGROUND

We recently identified two endothelial nitric oxide synthase (eNOS) gene polymorphisms, Glu298Asp and T-786-->C, which are independently associated with coronary spasm. eNOS gene intron 4b/a polymorphism is also reported to be involved in smoking-dependent coronary artery disease. The genetic linkage among these polymorphisms remains unknown. Also, it is unclear which variant is most responsible for coronary spasm. In the present study, we first examined the genetic linkage among these three variants. Next, we studied the risk factors of coronary spasm by using all significant genetic and conventional risk factors in a large-scale study.

METHODS

The genotype and allele frequencies for the T-786-->C, intron 4b/a, and Glu298Asp variants were assessed in 423 randomly selected DNA samples to examine their genetic linkages. The relative capacities of all risk factors to predict coronary spasm were then analyzed using multiple logistic regression in 201 patients with coronary spasm and 345 volunteers.

RESULTS

Comparison of allele frequencies revealed that the eNOS intron 4a allele was significantly linked to the T-786-->C mutation (P < 0.00001), whereas there was not a linkage between the intron 4a allele and the Glu298Asp variant (P = 0.1437) or between the Glu298Asp variant and the T-786-->C mutation (P = 0.1996). Multiple logistic regression revealed that the most predictive independent risk factor for coronary spasm was the T-786-->C mutation (P < 0.001), followed by cigarette smoking (P < 0.001), hypertension (P = 0.004), and the Glu298Asp variant (P = 0.028).

CONCLUSIONS

We found that the T-786-->C mutation and the intron 4a allele are in linkage disequilibrium. We previously showed that the T-786-->C mutation reduced eNOS gene promoter activity. In that context, our results strongly suggest that the T-786-->C mutation underlies the functional characteristics of the intron 4a allele. Further, multiple logistic regression analysis revealed that the T-786-->C mutation is the most predictive risk factor for coronary spasm, followed by cigarette smoking. Given that those effects are potentially additive, patients carrying the eNOS gene variants should be strongly cautioned against smoking.

Close linkage between calcium/calmodulin kinase II alpha/beta and NMDA-2A receptors in the lateral amygdala and significance for retrieval of auditory fear conditioning

The general mechanism underlying memory and learning is an area under intense investigation and debate, yet this mechanism still remains elusive. Auditory fear conditioning (when a tone is paired with a foot shock) is a simple associative form of learning for which many mechanistic details are known. Lesions of the lateral/basolateral nuclei of the amygdala result in the selective impairment of fear conditioning, indicating that this is a key region for this type of learning. Fear conditioning induces a lasting synaptic potentiation in the lateral nuclei of the amygdala. In addition, recent results from several laboratories suggest that N-methyl-D-aspartate (NMDA) receptor activation in the amygdala is required for the acquisition and expression of cue-conditioned fear responses using several kinds of antagonists. Little is known, however, about the signal transduction pathway and molecular substrate underlying fear conditioning. Here we use NMDA receptor-deficient mice to demonstrate that calmodulin-dependent kinase II, CaMKIIbeta, and CaMKIIalpha activation involves the NR2A subunit in the lateral/basolateral amygdala during memory retrieval following auditory fear conditioning. These results suggest that auditory fear conditioning involves a close linkage between NMDA2A receptors and the CaMKII cascade.

[Long-term effect of polystan monocusp ventricular outflow patch after right ventricular outflow tract reconstruction]

Forty-eight patients who underwent right ventricular outflow tract reconstruction with Monocusp Ventricular Outflow Patch (MVOP) fifty-five times and survived surgery, were reviewed in this study. Mean age at surgery was 6.4 years-old and mean follow-up interval was 75.2 months. There was no late death, however reoperation was performed 7 times. Freedom from reoperation rate was 97.2% and 80.7% after 5 and 10 years after surgery, respectively. The main cause for reoperation were right ventricular outflow obstruction RVOTO (5 cases). All of the RVOTO occurred at the distal end of the anastomosis. However, there was no RVOTO in patients who underwent RVOTR with MVOP during the past ten years. So, we considered the cause of RVOTO a technical problem. Pulmonary regurgitation was one to two degree early after surgery, and had worsened by almost two or three degrees more than 5 years after surgery. Moreover, five of six patients who underwent cardiac catheterization more than 10 years after surgery had three degrees of pulmonary regurgitation as well as a large CTR. In conclusion, according to long-term results, especially more than 10 years post operatively, pulmonary regurgitation was the most important problem.

Identification of a protein phosphorylated by cAMP-dependent protein kinase in drosophila brain

In the present study, we examined the effects of reagents that elevate cAMP concentration on protein phosphorylation in Drosophila brain cells. Application of forskolin or dopamine to brain cells that were prelabeled with (32)Pi enhanced phosphorylation of a 25-kDa protein (p25a). To identify p25a, we isolated the protein, and partial amino acid sequences were analyzed. Database searches showed that p25a is a J-domain protein, dJDP that contains the J-domain found in the DnaJ (heat shock protein 40) family of molecular chaperones.

HGF/SF-induced spreading of MDCK cells correlates with disappearance of barmotin/7H6, a tight junction-associated protein, from the cell membrane

Changes in expression of the two tight junction-associated proteins, barmotin/7H6 and ZO-1, as well as the adherence junction-associated protein, E-cadherin, were followed during hepatocyte growth factor/scatter factor (HGF/SC)-induced migration process of MDCK cells. Modulation of the HGF/SF-induced migration process by staurosporine, an inhibitor of protein kinase C (PKC), was also examined. Cell migration induced by HGF/SF consisted of two distinct phases, initial cell spreading between 2 and 9 h after the start of treatment, and the scattering phase which started approximately 12 h after treatment. Both ZO-1 and E-cadherin were expressed at the cell-cell border of adherent cells in the scattering phase, whereas barmotin/7H6, a barrier function-related tight junction protein, was not seen during the early spreading phase. Confluent cultures of MDCK cells, which did not spread after HGF/SF treatment, were positive for barmotin/7H6 expression at cell-cell borders. Blocking PKC activation during HGF/SF treatment with staurosporine inhibited cell spreading, and the cells retained barmotin/7H6 expression until at 6 h after HGF/SF treatment. The results indicate that disappearance of the tight junction protein, barmotin/7H6, is closely associated with cell spreading, with both barmotin/7H6 expression and cell spreading seemingly being regulated by PKC-mediated signaling.

Identification and characterization of STK12/Aik2: a human gene related to aurora of Drosophila and yeast IPL1

Mutations in aurora of Drosophila and related Saccharomyces cerevisiae IPL1 protein kinases are known to cause abnormal chromosome segregation. We earlier isolated a cDNA encoding a novel human protein kinase Aik which shares high amino acid identity with the Aurora/Ipl1 protein kinase family. In the present study, a second human cDNA highly homologous to aurora/IPL1 (Aik2) was identified and the nucleotide sequence was determined (gene symbol STK12). The C-terminal kinase domain of the STK12 encoded protein shares high amino acid sequence identity with those of mouse STK-1 (90%), rat AIM-1 (90%), human Aik (69%), mouse IAK1/Ayk1 (69%), Xenopus pEg2 (68%), Drosophila Aurora (62%), and yeast Ipl1 (45%), whereas the N-terminal domain of the STK12 protein shares little homology with those of Aurora/Ipl1 family members except for AIM-1 and STK-1. Northern blotting analyses revealed that STK12 expression was high in thymus, while low level expression was detected in small intestine, testis, colon, spleen, and brain. The STK12 protein content in HeLa cells is low in S phase, but it accumulates during M phase. STK12 was mapped to human chromosome 17p13.1 by fluorescence in situ hybridization. The chromosome location of STK12 was further defined using a radiation hybrid panel (Stanford G3), that showed a linkage with marker WI-7901 (LOD Score 7.83) located between D17S938 and D17S786.

Permeation of Liquids through Inorganic Nanofiltration Membranes

Inorganic nanofiltration membranes were prepared using silica-zirconia composite sols by the sol-gel method and applied for the permeation experiments of nonaqueous solutions. Pure solvent permeabilities of methanol, ethanol, and 1-propanol were measured at temperatures from 25 to 60 degrees C. For membranes having pore sizes as large as 70 nm, the permeation mechanism of alcohols obeys the viscous flow mechanism irrespective of types of alcohols. On the other hand, the permeation mechanism through porous silica-zirconia membranes having pore diameters of 1 to 5 nm was found to be different from the viscous flow mechanism; small molecules showed larger permeabilities than large molecules. Activation energies of solvent permeability were found to be larger for large molecules and for membranes of smaller pore size. Copyright 2000 Academic Press.

Local thrombus formation in the site of intravenous injection of chlorpromazine: possible colloid-osmotic lysis of the local endothelial cells

Since amphiphilic drugs are known to interact with biomembranes, we investigated local vessel damage and thrombosis which might be brought about by intravenous dosing using chlorpromazine (CPZ) as a representative compound. CPZ-induced hemolysis was suppressed by an increase in sucrose concentration in the medium, characterizing this hemolysis to be colloid-osmotic lysis, which includes the enhancement of membrane phospholipid fluidity and consequent small pore formation in the membranes. This was supported by the observation that hemolysis by filipin, not featuring the stage of small pore formation, was not affected by sucrose. [14C]Glucose-entrapping liposomes were degraded by CPZ, and this degradation was enhanced by an increase in the intravesicle glucose concentration. These results indicated that the compound could induce colloid-osmotic lysis in erythrocytes and artificial membrane vesicles. CPZ also injured cultured porcine aortic endothelial cells (PAEC), as evidenced by lactate dehydrogenase (LDH) leakage. This injury was also suppressed by increase in sucrose concentration in the medium, suggesting that colloid-osmotic lysis again occurred. When rats were intravenously injected with CPZ, local endothelial cell (EC) injury and associated thrombus formation were observed, suggesting that CPZ's action was also evident in vivo. To our knowledge, this is the first finding which suggests that an intravenously dosed amphiphilic drug can injure local ECs based on a colloid-osmotic lysis mechanism leading to thrombosis.

Inhibition of gelatinolytic activity in tumor tissues by synthetic matrix metalloproteinase inhibitor: application of film in situ zymography

Inhibition of gelatinolytic activity in implanted tumor tissues by oral administration of N-biphenyl sulfonyl-phenylalanine hydroxamic acid (BPHA), a selective matrix metalloproteinase (MMP) inhibitor, was demonstrated by means of film in situ zymography (FIZ). Active-MMP-2 but not pro-MMP-2 showed gelatinolytic activity in FIZ, whereas both forms of MMP-2 were found to be active in conventional zymography. A mixture of either tissue inhibitors of metalloproteinase-2 or BPHA with active-MMP-2 resulted in inhibition of gelatinolytic activity in FIZ but not in zymography. Thus, FIZ, but not zymography, could detect net MMP activity in tumor tissues. When a specimen from Ma44 human lung cancer xenograft was subjected to FIZ, gelatinolytic activity was markedly detected with precise localization in the tumor tissues. The gelatinolytic activity detected in Ma44 tumor tissues was found to be mainly derived from MMPs because the gelatin-degrading activity was inhibited by pretreatment of the tumor specimen with MMP inhibitors. Oral administration of BPHA but not (-)BPHA, an enantiomer of BPHA lacking MMP inhibitory activity, successfully inhibited the MMP activity localized in Ma44 tumor tissues in both a dose-dependent and time-dependent manner. The data presented in this report showed for the first time that oral administration of synthetic MMP inhibitor could inhibit the net activity of MMP activity in tumor tissues, suggesting the usefulness of the FIZ technique for determining the effective dose of MMP inhibitor in clinical studies.

Sp1-like activity mediates angiotensin-II-induced plasminogen-activator inhibitor type-1 (PAI-1) gene expression in mesangial cells

Angiotensin II (Ang II) up-regulates plasminogen-activator inhibitor type-1 (PAI-1) expression in mesangial cells to enhance extracellular matrix formation. The proximal promoter region (bp -87 to -45) of the human PAI-1 gene contains several potent binding sites for transcription factors [two phorbol-ester-response-element (TRE)-like sequences; D-box (-82 to -76) and P-box (-61 to 54), and one Sp1 binding site-like sequence, Sp1-box 1 (-72 to -67)]. We studied this region to determine the transcription factor(s) that mediates Ang-II-induced transcriptional activation of the PAI-1 gene. Various double-stranded decoy oligodeoxynucleotides (ODNs) corresponding to various sequences in the proximal promoter region were transfected to mesangial cells to examine the effects on Ang-II-induced PAI-1 mRNA expression. Transfection with the full-length decoy (bp -87 to -45, D-P-ODN) markedly attenuated Ang-II-induced PAI-1 mRNA expression by up to 70%. Transfection with D-ODN (-87 to -71) and P-ODN (-66 to -45), which correspond to each of the two TRE-like sequences, did not attenuate the expression. Gel-shift assays using nuclear extracts prepared from Ang-II-treated mesangial cells and D-P-ODN showed three specific complexes. The major complex was supershifted by anti-Sp1 antibody. The methylation-interference experiment demonstrated that human recombinant Sp1 bound to the so-called GT box (TGGGTGGGGCT, -78 to -69), which contains the Sp1-box 1. The complex that migrated with anti-Sp1 antibody was enhanced in the cells treated with Ang II. Further, D-Sp1-ODN (-85 to -63) containing the GT box attenuated up-regulation of PAI-1 mRNA expression induced by Ang II to a level (68+/-9% inhibition) comparable to D-P-ODN, whereas ODN with four mutations in the GT box had no effect. Our findings suggest that binding of Sp1 or an Sp1-like transcription factor to the GT box in the PAI-1 promoter up-regulates PAI-1 gene transcription in mesangial cells stimulated with Ang II. This transcription-factor binding site may be targeted to control Ang-II-dependent extracellular matrix formation by mesangial cells.

Changes in contused lung volume and oxygenation in patients with pulmonary parenchymal injury after blunt chest trauma

Although it is well known that pulmonary parenchymal injury impairs oxygenation, the relationship between hypoxemia and volume of the contused lung after blunt chest trauma remains unknown. We studied 23 blunt chest trauma patients who underwent thoracic computed tomography (CT) within 24 hours after admission and also underwent follow-up CT at 1-week intervals until abnormal lung findings disappeared. Contused lung volume was determined quantitatively by CT. CT findings of parenchymal injury were either a diffuse lesion that disappeared within 1 week (n = 9 patients, group 1), or a solitary lesion that remained a few weeks after resolution of the diffuse lesion (n = 14 patients, group 2). PaO2/FiO2 was positively correlated with the volume of contused lung during the first 24 hours in both groups, however, there was no significant correlation after 1 week after injury. Degree of impaired oxygenation is related to the volume of the diffuse lesion that is recognized soon after injury.

Role of inflammatory mediators in lipid A analogue (ONO-4007)-induced vascular permeability change in mouse skin

1. Endotoxin shock is accompanied by an increase in peripheral vascular permeability. It has been postulated that most biological activities of LPS are derived from lipid A moiety. Here we examined the effect of lipid A analogue ONO-4007 in increasing vascular permeability and the possible mediators in mouse skin by a dye leakage method. 2. Subcutaneous injection of ONO-4007 (1 - 2 mg site(-1)) induced a dose-dependent increase in vascular permeability which was evident after 120 min. 3. ONO-4007-induced dye leakage was significantly attenuated by pretreatments with anti-tumour necrosis factor-alpha (TNF-alpha) and anti-interleukin-1alpha (IL-1alpha) antibodies, but not with indomethacin (5 mg kg(-1)) or diphenhydramine (10 mg kg(-1)). ONO-4007-induced dye leakage was significantly inhibited by a pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME) (10 mg kg(-1)) but not with aminoguanidine (50 mg kg(-1)). In inducible nitric oxide synthase (iNOS)-deficient mice, ONO-4007 significantly increased the dye leakage, while ONO-4007 dilated rat thoracic aortic rings pre-contracted with phenylephrine, and the L-NAME pretreatment inhibited the dilation. 4. Thus, TNF-alpha, IL-1alpha and constitutive NOSs-derived nitric oxide but not prostaglandins or histamine play a role in ONO-4007-induced increase in vascular permeability. Although ONO-4007 mimics LPS in increasing vascular permeability, mechanisms of permeability change elicited by ONO-4007 were not identical to those of LPS.

The impact of a catastrophic earthquake on morbidity rates for various illnesses

It has been reported that some natural catastrophes increase morbidity rates for illness. In this study, we investigated the impact of the 1995 Hanshin-Awaji earthquake on morbidity rates for various illnesses by analysis for correlations between the extent of damage due to the earthquake and occurrences of various illnesses. We searched the medical records of 1948 patients hospitalized due to illness in 48 hospitals during the first 15 days after the earthquake. In each of 14 affected areas, the hospital admission rate and estimated morbidity ratio for each illness were calculated. Destruction ratios were determined based upon the number of dwellings completely destroyed in each area. For total illnesses and each major illness, linear regression analyses were performed comparing hospital admission rates, estimated morbidity ratios, and destruction ratios. Hospital admission rates and estimated morbidity ratios among the 1948 patients were significantly correlated to destruction ratios. With pneumonia, dehydration, acute heart failure, asthmatic attack, and peptic ulcer, hospital admission rates and estimated morbidity ratios were significantly related to destruction ratios, while no significant correlations between estimated morbidity ratios and destruction ratios existed for cerebral vascular disease or ischemic heart disease. Peptic ulcer and pneumonia showed especially high correlation values (age- and sex-adjusted R2>0.7). The present study revealed a strong link between the extent of damage due to the catastrophic earthquake and an increase in morbidity rates for acute illnesses, especially peptic ulcer and pneumonia.

Examination of microgravity effects on spontaneous Ca2+ oscillations in AtT20 pituitary cells using heavy water

Effects of heavy water (D2O) on various organisms have been extensively studied and a majority of D2O actions were generally ascribed to the viscosity (1.23 times of H2O) and a larger inter-molecule force of D2O that may eventually alternate molecular structure of various enzymes and ion channels. It is reported that chronic application of D2O induces toxic effects and the 35% substitution of whole body water with D2O induced fatal effects in the mouse. Mitosis of a fertile egg of sea urchin was completely inhibited by 75% D2O but the paused segmentation was recovered after rinse of D2O. In addition, we also observed that neuronal development of the Lymnaea stagnalis was reversibly inhibited by D2O (M. Sakakibara, unpublished data). However, mechanism of the toxicity of D2O and the effects of D2O on cellular events have not been fully understood. The spontaneous oscillation in cytosolic free Ca2+ concentration is one of the typical physiological events in living secretory cells. We previously demonstrated that the Ca2+ oscillations are regulated by voltage-sensitive Ca2+ channels (VSCC), Ca2+ ATPases, and Ca(2+)-induced Ca2+ release from intracellular stores. To analyze the site(s) of action of D2O in the living cellular systems, the present study examined effects of D2O on the Ca2+ mobilization and resting membrane potentials in AtT20 mouse pituitary cells.

[An application of fusion fluorescent proteins in the pharmacological study of intracellular protein trafficking]

The fluorescent proteins have expanded various aspects of biological research. Proteins fused to the fluorescent proteins such as green fluorescent protein (GFP) provided researchers an opportunity to visualize the intracellular trafficking of proteins in living cells. The trafficking of proteins including that of steroid receptors involves dynamic interactions with cellular proteins such as heat shock proteins, immunophilins. Such interactions, which can be monitored by GFP fusion proteins, may be altered by pathophysiological conditions and by drugs. Thus, GFP fusion proteins may be applied to the investigations for the pharmacological manipulation of protein trafficking.

[Experimental study of esophageal covered stent for prevention of migration: use of clay to simulate stenosis of the esophagogastric junction or anastomosis site]

PURPOSE

An inner-covered Spiral Z-stent (IC-SZ) developed by our group was examined for its effectiveness in preventing migration by experimental comparison with commercially available esophageal covered stents.

MATERIALS AND METHODS

The following six types of stents were used: inner-covered Spiral Z-stents with diameters of 16 mm (small IC-SZ) and 19 mm (large IC-SZ), outer-covered Spiral Z-stent (OC-SZ), covered Wallstent, covered Ultraflex stent, and Cook Z-stent. Experimental models were prepared using clay to simulate stenosis of the esophagogastric junction or anastomosis site due to tumor, and each stent was placed in the clay. After the stent had been fully expanded with a balloon catheter, one of its ends was pulled until the stent migrated out of the clay, and the traction force was measured. The inner cavity of the stent placed in the clay was observed using an endoscope.

RESULTS

The mean maximal traction force required to pull the stents out of the clay were as follows, in decreasing order: 4.14 +/- 0.39 kg for the large IC-SZ, 4.12 +/- 0.83 kg for the small IC-SZ, 3.64 +/- 0.44 kg for the Cook Z-stent (p < 0.05), 3.34 +/- 0.62 kg for the covered Ultraflex stent (p < 0.05), 1.53 +/- 0.43 kg for the OC-SZ (p < 0.01), and 0.56 +/- 0.16 kg for the covered Wallstent (p < 0.01). The force required to pull out the large IC-SZ stent was the greatest, showing a significant difference from the values for the other four types of stents (excluding the small IC-SZ). Observation using an endoscope revealed that the wire of the IC-SZ stent was almost entirely embedded in the clay, whereas the wires of other stents were not.

CONCLUSION

The IC-SZ stent may be less likely to migrate than other esophageal covered stents.

Effect of lipoteichoic acid on dermal vascular permeability in mice

Lipoteichoic acid (LTA), the cell wall component of Gram-positive bacteria, has been shown to cause inflammatory responses comparable to lipopolysaccharide (LPS) of Gram-negative bacteria. This study examined the activity of LTA to induce dermal microvascular permeability changes in mice. Vascular permeability was assessed by extravasation of Pontamine sky blue. Subcutaneous injection of LTA (200-400 microg/site) in mice that were preinjected i.v. with the dye increased local dye leakage in the skin at 1 to 3 h. The LTA-induced dye leakage was inhibited by indomethacin, valeryl salicylate, diphenhydramine, and a platelet-activating factor antagonist but not by inhibitors of nitric-oxide synthase, cyclooxygenase-2, or guanylate cyclase or by antibodies against tumor necrosis factor-alpha or interleukin-1alpha. LTA induced comparable increases in dye leakage in inducible nitric-oxide synthase-deficient mice and wild-type controls. Pretreatment of normal mice with i.v. LTA did not confer tolerance to LTA- or LPS-induced dye leakage. In contrast, systemic LPS administration induced tolerance against subsequent challenge with LPS but not LTA. Serum corticosterone levels, which were suggested to induce tolerance, were not increased by LTA pretreatment but were increased by LPS. Thus, LTA increases dermal microvascular permeability in mice. Among the inflammatory mediators, eicosanoids, platelet-activating factor, and histamine mediate the effect of both LTA and LPS, whereas nitric oxide, tumor necrosis factor-alpha, and interleukin-1alpha may not play a major role in LTA-induced dye leakage. The difference between LTA and LPS to stimulate corticosterone may partially explain the failure of LTA to induce tolerance against vascular dye leakage.

Role of nuclear lamins in nuclear segmentation of human neutrophils

Nuclear breakdown leading to the formation of apoptotic bodies has been postulated to involve degradation of nuclear structural proteins, such as lamins A/C and B. Although nuclear segmentation occurs during the maturation of polymorphonuclear leukocytes (neutrophils), its mechanism is not known. We found that human neutrophils have lamin B but lack lamins A/C while mononuclear cells possess all three types of lamin as assessed by immunoblotting. Differentiation of human promyelocytic HL-60 cells into neutrophil-like cells was also accompanied by the down-regulation of lamins A/C but not of lamin B. Moreover, when compared with normal cells, neutrophils with the Pelger-Huët anomaly of nuclear hyposegmentation exhibited significantly lower activity of caspase-6, a lamin A/C-cleaving enzyme. Differentiated HL-60 cells showed higher activity of caspase-6 than that of untreated cells. These observations allow us to speculate that remodeling of nuclear lamins might underlie the mechanism for nuclear segmentation of neutrophils.

Pre- and postsynaptic actions of serotonin on rat suprachiasmatic nucleus neurons

Serotoninergic transmission is implicated in the photic and non-photic regulation of circadian rhythms. 5-HT (1-100 microM), carboxamidotryptamine (5-CT 0.1-10 microM) and (+)-8-hydroxy-dipropylaminotetraline (8-OH-DPAT, 1-30 microM) dose-dependently activated an outward current (5-100 pA) in 30% of neurons voltage-clamped at -60 mV in the suprachiasmatic nucleus (SCN) in vitro slice. EC(50) values were 7.0 microM for 5-HT and 0.2 microM for 5-CT. Serotonin-induced outward current was associated with an increase in input conductance, and the current was blocked by Ba(2+) (1 mM). The amplitude of the current was enhanced by depolarization, reduced by hyperpolarization, and reversed its polarity during a hyperpolarization beyond the potassium equilibrium potential. Mean amplitudes of the 5-HT outward current changed with time of the subjective circadian day. The value near CT2 (23.8 pA) was about 4 times greater than that around CT14 (6.7 pA). Cells that responded with an outward current showed four types of morphology: monopolar, simple bipolar, curly bipolar and radial shaped; they were localized in all parts of the SCN. The EPSC evoked by retino-hypothalamic-tract (RHT) stimulation was inhibited 26% but the inward current induced by exogenously applied glutamate or NMDA was not affected by serotonin agonists. Focal stimulation-induced and spontaneous IPSC but not the exogenous GABA-induced outward current were inhibited by 5-HT agonists in a subpopulation of cells. In conclusion, 5-HT regulates SCN neurons by both pre- and post-synaptic inhibitory mechanisms; the latter may play a key role in modulating SCN circadian rhythm by activation of 5-HT receptors and opening of a potassium channel.

Restricted usage of T-cell receptor alpha-chain variable region (TCRAV) and T-cell receptor beta-chain variable region (TCRBV) repertoires after human allogeneic haematopoietic transplantation

We analysed T-cell receptor alpha-chain variable region (TCRAV) and T-cell receptor beta-chain variable region (TCRBV) repertoires in peripheral blood mononuclear cells (PBMCs) from 34 recipients of allogeneic bone marrow transplantation (allo-BMT), seven of allogeneic peripheral blood stem cell transplantation and 19 of autologous peripheral blood stem cell transplantation using the quantitative microplate hybridization assay. TCR usage skewed at an early period (6-7 weeks) after BMT. The change was more apparent in allogeneic recipients than in autologous recipients. In particular, a predominant increase was detected in the frequency of VA1-4 (26%, 11 of 41 recipients), VA3-1 (32%) and VB24-1 (28%). Interestingly, acidic amino acid residues frequently followed the arginine residue in complementarity-determining region 3 of BV24S1. We further examined the extent of skew using samples obtained at serial time points after transplantation. The normalization of skewed repertoires occurred over a long period of time (> 8 years). There was a significant difference in the rate of normalization of skewed TCR repertoires between adult and child recipients (P < 0.05). The results suggest that these T cells may have expanded in response to allogeneic antigens, such as miHA (minor histocompatibility antigen), and that altered repertoires are eventually normalized by T-cell regeneration via a thymic-dependent pathway in children.

Caspase activation and cytochrome c release during HL-60 cell apoptosis induced by a nitric oxide donor

Nitric oxide (NO) from (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1- ium-1,2-diolate (NOC-18) induces apoptosis in human leukemia HL-60 cells. This effect was prevented by the pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone (Z-VAD-FMK), thereby implicating caspase activity in the process. NOC-18 treatment resulted in the activation of several caspases including caspase-3, -6, -8, and -9(-like) activities and the degradation of several caspase substrates such as nuclear lamins and SP120 (hnRNP-U/SAF-A). Moreover, release of cytochrome c from mitochondria was also observed during NOC-18-induced apoptosis. This change was substantially prevented by Z-VAD-FMK, thereby suggesting that the released cytochrome c might function not only as an initiator but also as an amplifier of the caspase cascade. Bid, a death agonist member of the Bcl-2 family, was processed by caspases following exposure of cells to NOC-18, supporting the above notion. Thus, NO-mediated apoptosis in HL-60 cells involves a caspase/cytochrome c-dependent mechanism.

Aortic stent-grafting with transrenal fixation: use of newly designed spiral Z-stent endograft

PURPOSE

To evaluate the feasibility and efficacy of a newly designed stent-graft placed across the renal arteries for exclusion of abdominal aortic aneurysms (AAAs) with short or tortuous proximal necks.

METHODS

Among a group of AAA patients treated with endovascular grafting, 5 had tortuous proximal necks and 13 had necks <20 mm (mean 13 mm). In these 18 cases, a 2- to 3-cm uncovered segment of the stent-graft was placed transrenally using a catheter inserted into the renal artery as a guide for graft margin positioning. A newly designed stent-graft was constructed from a custom-made spiral Z-stent covered with a thin-walled Dacron material; the endografts were deployed through 16-F (aortoaortic model) or 18-F sheaths (bifurcated devices). Renal function was assessed by preoperative and postoperative measurement of urea nitrogen and creatinine. Aneurysm exclusion and renal artery patency were evaluated during follow-up using spiral computed tomography and angiography.

RESULTS

The stent-grafts were correctly placed at the intended site in all 18 patients. Renal function was not affected except transiently in 1 patient who developed bilateral renal artery stenoses 24 hours after the procedure; Palmaz stents were deployed in each renal artery to reestablish satisfactory blood flow. Of the 33 renal arteries crossed by the bare stent-graft segment, all were patent over a mean 14-month follow-up (range 7-24), including the patient with Palmaz stents implanted for postprocedural renal stenosis. Complete aneurysm exclusion was maintained in 15 (83%) of 18 patients; proximal leaks persisted in 3 patients, including 2 with severely angled proximal necks.

CONCLUSIONS

Transrenal placement of the uncovered leading edge of custom-made spiral Z-stent-based endografts appears feasible and clinically effective in the treatment of AAAs with short or tortuous proximal necks.

Developmental change of GABA(A) receptor-mediated current in rat hippocampus

Developmental change of GABA(A)ergic inhibitory postsynaptic current in rat hippocampal CA3 region was examined using patch-clamp recording method. Spontaneous and evoked inhibitory postsynaptic currents were recorded from acute hippocampal slices of neonates (postnatal days 2-4) and adults (days 18-38). Decay kinetics of the spontaneous inhibitory postsynaptic current was slower in neonates than in adults. Application of 500 nM zolpidem increased decay time-constants of the inhibitory postsynaptic currents in both groups with a stronger effect on adults. Zinc (50 microM) inhibited the neonatal inhibitory postsynaptic currents but the inhibition was weaker in adults. Modification of the GABA(A)ergic inhibitory postsynaptic currents by furosemide (0.6 mM) or diazepam (100 nM) did not cause marked differences between the neonate and adult groups. These results demonstrate that GABA(A)ergic inhibitory postsynaptic currents in hippocampal CA3 pyramidal cells change developmentally and indicate that different receptor isoforms are functionally expressed between neonates and adults.

Involvement of glial fibrillary acidic protein (GFAP) expressed in astroglial cells in circadian rhythm under constant lighting conditions in mice

To clarify the role of glial fibrillary acidic protein (GFAP)-expressed glial cells in the circadian clock, we examined GFAP expression in the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) under various lighting conditions in mice. We demonstrated that GFAP expression did not show daily change in the SCN under a light-dark cycle; however, long-term housing under constant lighting conditions led to dramatic changes in GFAP expression, i.e., a decrease in the SCN and an increase in the IGL. Furthermore, mice that had a targeted deletion in the GFAP gene (GFAP mutant mice) showed longer and more arrhythmic circadian activity rhythms in constant lighting conditions than wild-type mice, while GFAP mutant mice exhibited stable circadian rhythms both in a light-dark cycle and constant darkness, and showed normal entrainment to environmental light stimuli. These results suggest that the GFAP-expressed astroglial cells in the SCN and the IGL may have some role in circadian oscillation under constant lighting conditions.

PLC beta 4-independent Ca2+ rise via muscarinic receptors in the mouse suprachiasmatic nucleus

Cholinergic regulation of the suprachiasmatic nucleus (SCN) has been extensively studied although the intracellular signaling mechanisms are not well understood. We examined immunostaining for phospholipase C-beta (PLC-beta) families that couple to muscarinic acetylcholine receptors (mAChR) and demonstrated the expression of PLC-beta 1 and beta 4 in the mouse SCN. Ca2+ imaging analysis indicated that the MI-mAChR antagonist, pirenzepine blocked carbachol-induced Ca2+ elevation in the SCN and the response was equivalent between the wild type and the PLC-beta 4-knockout mice. In addition, the knockout mice displayed locomotor and temperature rhythms coupling to 24 h light/dark cycles. Therefore, it was proposed that PLC-beta 1 but not PLC-beta 4 was involved in the mAChR-mediated Ca2+ signaling in the SCN.

Rat receptor-activity-modifying proteins (RAMPs) for adrenomedullin/CGRP receptor: cloning and upregulation in obstructive nephropathy

Adrenomedullin (AM) is a potent vasorelaxing peptide originally isolated pheochromocytoma. Recently, a family of receptor-activity-modifying proteins (RAMPs 1-3) were identified in humans. Associated with the calcitonin receptor-like receptor (CRLR), RAMP2 or RAMP3 may function as the AM receptor. Here we cloned rat RAMP family, analyzed their distribution in rat tissues, and examined regulation of their expression in the kidney using an obstructive nephropathy model. Northern blot analyses revealed that the RAMP family genes are expressed in various tissues with different tissue specificity; RAMP1 is abundantly expressed in the brain, fat, thymus, and spleen, RAMP2 in the lung, spleen, fat, and aorta, while RAMP3 is most abundant in the kidney and lung. After ureteral obstruction, RAMP1, RAMP2, and CRLR gene expressions in the obstructed kidney were markedly upregulated, whereas RAMP3 expression was unchanged. Thus, RAMPs are regulated differently in obstructive nephropathy, suggesting their distinct roles in renal pathophysiology.

Dentin bonding and sealing ability of a new root canal resin sealer

The aims of this study were to find a dentin bonding system suitable for root canal treatment using a newly developed root canal resin sealer, and to examine its sealing ability. The sealer was composed of vinylidene fluoride/hexafluoropropylene copolymer, methyl methacrylate, zirconia, and tributylborane catalyst. The effects of dentin conditioners and primers on dentin bonding were studied by tensile bond strength testing and scanning electron microscopy. Apical and coronal leakage were evaluated at 1-, 4-, and 12-wk intervals by a dye penetration test using a methylene blue solution. Pulp Canal Sealer EWT and Sealapex were used as controls. Significantly high bond strength was obtained by treating dentin with EDTA, followed by application of a glutaraldehyde/2-hydroxyethyl methacrylate primer. The experimental resin sealer produced a significantly superior coronal seal at 12 wk when compared with the two control sealers (p < 0.05). Scanning electron microscopic examination revealed few gaps at the resin sealer-dentin interface.

Anti-NO action of carvedilol in cell-free system and in vascular endothelial cells

1. Carvedilol, an adrenoceptor blocker with antioxidant activity, was studied for its ability to interact with NO in a cell-free condition and in an endothelial cell line (ECV304). 2. In a cell-free system, carvedilol attenuated NO-dependent reduction of carboxy-2-phenyl-4,4, 5,5-tetramethyl-imidazoline-1-oxyl-3-oxide induced by a NO donor, 1-hydroxy-2-oxo-3-(aminopropyl)-3-isopropyl-1-triazene (NOC5), which was determined by electron paramagnetic resonance (EPR) spectrometry. The EPR study also showed that nitrosylhaemoglobin formation in rat red blood cells by the addition of NO-saturated solution was attenuated by prior incubation with 0.1 - 10 microM carvedilol. 3. NO-induced fluorescence in 4,5-diaminofluorescein-2 diacethyl (DAF-2DA)-loaded ECV304 cells was attenuated by carvedilol but not by labetalol. The IC(50) of carvedilol for NOC5 or sodium nitroprusside-induced fluorescence of DAF-2DA in ECV304 cells was 1. 0x10(-7) M, which was similar to the reported IC(50) of carvedilol for the antioxidant effect. 4. Cell toxicity induced by a NO donor determined by the number of viable cells after 24 h treatment with 2-2'(hydroxynitrosohydrazino)bis-ethanamine was significantly attenuated by pretreatment with 1 microM carvedilol. 5. Both free and cell-associated carvedilol quenched NO. Because NO mediates both physiological and pathophysiological processes, NO quenching by the drug may have diverse clinical implications depending upon specific functions of local NO in tissues where carvedilol is distributed.