A small-molecule, nonpeptide CCR5 antagonist with highly potent and selective anti-HIV-1 activity

The beta-chemokine receptor CCR5 is considered to be an attractive target for inhibition of macrophage-tropic (CCR5-using or R5) HIV-1 replication because individuals having a nonfunctional receptor (a homozygous 32-bp deletion in the CCR5 coding region) are apparently normal but resistant to infection with R5 HIV-1. In this study, we found that TAK-779, a nonpeptide compound with a small molecular weight (Mr 531.13), antagonized the binding of RANTES (regulated on activation, normal T cell expressed and secreted) to CCR5-expressing Chinese hamster ovary cells and blocked CCR5-mediated Ca2+ signaling at nanomolar concentrations. The inhibition of beta-chemokine receptors by TAK-779 appeared to be specific to CCR5 because the compound antagonized CCR2b to a lesser extent but did not affect CCR1, CCR3, or CCR4. Consequently, TAK-779 displayed highly potent and selective inhibition of R5 HIV-1 replication without showing any cytotoxicity to the host cells. The compound inhibited the replication of R5 HIV-1 clinical isolates as well as a laboratory strain at a concentration of 1.6-3.7 nM in peripheral blood mononuclear cells, though it was totally inactive against T-cell line-tropic (CXCR4-using or X4) HIV-1.

Rim is a putative Rab3 effector in regulating synaptic-vesicle fusion

Rab3 is a neuronal GTP-binding protein that regulates fusion of synaptic vesicles and is essential for long-term potentiation of hippocampal mossy fibre synapses. More than thirty Rab GTP-binding proteins are known to function in diverse membrane transport pathways, although their mechanisms of action are unclear. We have now identified a putative Rab3-effector protein called Rim. Rim is composed of an amino-terminal zinc-finger motif and carboxy-terminal PDZ and C2 domains. It binds only to GTP (but not to GDP)-complexed Rab3, and interacts with no other Rab protein tested. There is enrichment of Rab3 and Rim in neurons, where they have complementary distributions. Rab3 is found only on synaptic vesicles, whereas Rim is localized to presynaptic active zones in conventional synapses, and to presynaptic ribbons in ribbon synapses. Transfection of PC12 cells with the amino-terminal domains of Rim greatly enhances regulated exocytosis in a Rab3-dependent manner. We propose that Rim serves as a Rab3-dependent regulator of synaptic-vesicle fusion by forming a GTP-dependent complex between synaptic plasma membranes and docked synaptic vesicles.

Semiquantitative grading of severity of mitral regurgitation by real-time two-dimensional Doppler flow imaging technique

An attempt was made to determine whether mitral regurgitation could be detected and its severity evaluated semiquantitatively by newly developed real-time two-dimensional Doppler flow imaging in 109 patients who underwent left ventriculography. In the Doppler flow imaging technique, Doppler signals due to blood flow in the cardiac chambers are processed using a high speed autocorrelation technique, so that the direction, velocity and turbulence of the intracardiac blood flow are displayed in the color-coded mode on the monochrome B-mode echocardiogram in real time. Mitral regurgitant flow was imaged as a jet spurting out from the mitral valve orifice into the left atrial cavity. It was noted that the regurgitant jet in the left atrial cavity had a variety of orientations and dynamic features when studied by the present technique. The sensitivity of the technique in the detection of mitral regurgitation was 86% as compared with that of left ventriculography. Mitral regurgitation in the false negative cases was mostly mild. On the basis of the farthest distance reached by the regurgitant flow signal from the mitral valve orifice, the severity of regurgitation was graded on a four point scale and these results were compared with those of angiography. A significant correlation (r = 0.87) was found between Doppler imaging and angiography in the evaluation of the severity of mitral regurgitation. A similar result was obtained for the evaluation based on the area covered by the regurgitant signals in the left atrial cavity. Thus, noninvasive semiquantitative evaluation by real-time two-dimensional Doppler flow imaging appears to be a promising clinical technique.

A tripartite protein complex with the potential to couple synaptic vesicle exocytosis to cell adhesion in brain

We identify a complex of three proteins in brain that has the potential to couple synaptic vesicle exocytosis to neuronal cell adhesion. The three proteins are: (1) CASK, a protein related to MAGUKs (membrane-associated guanylate kinases); (2) Mint1, a putative vesicular trafficking protein; and (3) Veli1, -2, and -3, vertebrate homologs of C. elegans LIN-7. CASK, Mint1, and Velis form a tight, salt-resistant complex that can be readily isolated. CASK, Mint1, and Velis contain PDZ domains in addition to other modules. However, no PDZ domains are involved in complex formation, leaving them free to recruit cell adhesion molecules, receptors, and channels to the complex. We propose that the tripartite complex acts as a nucleation site for the assembly of proteins involved in synaptic vesicle exocytosis and synaptic junctions.

Augmentation of atrial contribution to left ventricular inflow with aging as assessed by intracardiac Doppler flowmetry

The influence of aging on the left ventricular (LV) function in diastole was investigated from the aspect of the mitral inflow pattern using 2-dimensional Doppler echocardiography. The subjects for the investigation were 69 persons who were diagnosed as healthy by a checkup examination. The peak velocity in the rapid filling phase and that in the atrial contraction phase tended to decrease and to increase with aging, respectively. However, these tendencies were not statistically significant. However, the ratio of the atrial contraction phase to the rapid filling phase showed a significant increase with aging (r = 0.82, p less than 0.001). Therefore, it is considered that the mitral flow conditions are influenced by aging. The result obtained is also interpreted to mean that the LV distensibility in early diastole is impaired with aging and that the contribution of the atrial contraction to LV filling is compensatorily augmented.

Nintedanib in patients with progressive fibrosing interstitial lung diseases-subgroup analyses by interstitial lung disease diagnosis in the INBUILD trial: a randomised, double-blind, placebo-controlled, parallel-group trial

BACKGROUND

The INBUILD trial investigated the efficacy and safety of nintedanib versus placebo in patients with progressive fibrosing interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis (IPF). We aimed to establish the effects of nintedanib in subgroups based on ILD diagnosis.

METHODS

The INBUILD trial was a randomised, double-blind, placebo-controlled, parallel group trial done at 153 sites in 15 countries. Participants had an investigator-diagnosed fibrosing ILD other than IPF, with chest imaging features of fibrosis of more than 10% extent on high resolution CT (HRCT), forced vital capacity (FVC) of 45% or more predicted, and diffusing capacity of the lung for carbon monoxide (DLco) of at least 30% and less than 80% predicted. Participants fulfilled protocol-defined criteria for ILD progression in the 24 months before screening, despite management considered appropriate in clinical practice for the individual ILD. Participants were randomly assigned 1:1 by means of a pseudo-random number generator to receive nintedanib 150 mg twice daily or placebo for at least 52 weeks. Participants, investigators, and other personnel involved in the trial and analysis were masked to treatment assignment until after database lock. In this subgroup analysis, we assessed the rate of decline in FVC (mL/year) over 52 weeks in patients who received at least one dose of nintedanib or placebo in five prespecified subgroups based on the ILD diagnoses documented by the investigators: hypersensitivity pneumonitis, autoimmune ILDs, idiopathic non-specific interstitial pneumonia, unclassifiable idiopathic interstitial pneumonia, and other ILDs. The trial has been completed and is registered with ClinicalTrials.gov, number NCT02999178.

FINDINGS

Participants were recruited between Feb 23, 2017, and April 27, 2018. Of 663 participants who received at least one dose of nintedanib or placebo, 173 (26%) had chronic hypersensitivity pneumonitis, 170 (26%) an autoimmune ILD, 125 (19%) idiopathic non-specific interstitial pneumonia, 114 (17%) unclassifiable idiopathic interstitial pneumonia, and 81 (12%) other ILDs. The effect of nintedanib versus placebo on reducing the rate of FVC decline (mL/year) was consistent across the five subgroups by ILD diagnosis in the overall population (hypersensitivity pneumonitis 73·1 [95% CI -8·6 to 154·8]; autoimmune ILDs 104·0 [21·1 to 186·9]; idiopathic non-specific interstitial pneumonia 141·6 [46·0 to 237·2]; unclassifiable idiopathic interstitial pneumonia 68·3 [-31·4 to 168·1]; and other ILDs 197·1 [77·6 to 316·7]; p=0·41 for treatment by subgroup by time interaction). Adverse events reported in the subgroups were consistent with those reported in the overall population.

INTERPRETATION

The INBUILD trial was not designed or powered to provide evidence for a benefit of nintedanib in specific diagnostic subgroups. However, its results suggest that nintedanib reduces the rate of ILD progression, as measured by FVC decline, in patients who have a chronic fibrosing ILD and progressive phenotype, irrespective of the underlying ILD diagnosis.

FUNDING

Boehringer Ingelheim.

Predicting the development of gastric cancer from combining Helicobacter pylori antibodies and serum pepsinogen status: a prospective endoscopic cohort study

BACKGROUND AND AIMS

Helicobacter pylori infection and gastric atrophy are both risk factors for gastric cancer. We aimed to elucidate the natural history of gastric cancer development according to H pylori infection and gastric atrophy status.

SUBJECTS AND METHODS

A total of 9293 participants in a mass health appraisal programme were candidates for inclusion in the present prospective cohort study: 6983 subjects revisited the follow up programme. Subjects were classified into four groups according to serological status at initial endoscopy. Group A (n = 3324) had "normal" pepsinogen and were negative for H pylori antibody; group B (n = 2134) had "normal" pepsinogen and were positive for H pylori antibody; group C (n = 1082) had "atrophic" pepsinogen and were positive for H pylori antibody; and group D (n = 443) had "atrophic" pepsinogen and were negative for H pylori antibody. Incidence of gastric cancer was determined by annual endoscopic examination.

RESULTS

Mean duration of follow up was 4.7 years and the average number of endoscopic examinations was 5.1. The annual incidence of gastric cancer was 0.04% (95% confidence interval (CI) 0.02-0.09), 0.06% (0.03-0.13), 0.35% (0.23-0.57), and 0.60% (0.34-1.05) in groups A, B, C, and D, respectively. Hazard ratios compared with group A were 1.1 (95% CI 0.4-3.4), 6.0 (2.4-14.5), and 8.2 (3.2-21.5) in groups B, C, and D, respectively. Age, sex, and "group" significantly served as independent valuables by multivariate analysis.

CONCLUSIONS

The combination of serum pepsinogen and anti-H pylori antibody provides a good predictive marker for the development of gastric cancer.

Tobacco MAP kinase: a possible mediator in wound signal transduction pathways

A complementary DNA encoding a mitogen-activated protein (MAP) kinase homolog has been isolated from tobacco plants. Transcripts of the corresponding gene were not observed in healthy tobacco leaves but began to accumulate 1 minute after mechanical wounding. In tobacco plants transformed with the cloned complementary DNA, trans inactivation of the endogenous homologous gene occurred, and both production of wound-induced jasmonic acid and accumulation of wound-inducible gene transcripts were inhibited. In contrast, the levels of salicylic acid and transcripts for pathogen-inducible, acidic pathogenesis-related proteins were increased upon wounding. These results indicate that this MAP kinase is part of the initial response of higher plants to mechanical wounding.

Coordination of microtubules and the actin cytoskeleton by the Rho effector mDia1

Coordination of microtubules and the actin cytoskeleton is important in several types of cell movement. mDia1 is a member of the formin-homology family of proteins and an effector of the small GTPase Rho. It contains the Rho-binding domain in its amino terminus and two distinct regions of formin homology, FH1 in the middle and FH2 in the carboxy terminus. Here we show that expression of mDia1(DeltaN3), an active mDia1 mutant containing the FH1 and FH2 regions without the Rho-binding domain, induces bipolar elongation of HeLa cells and aligns microtubules in parallel to F-actin bundles along the long axis of the cell. The cell elongation and microtubule alignment caused by this mutant is abolished by co-expression of an FH2-region fragment, and expression of mDia1(DeltaN3) containing point mutations in the FH2 region causes an increase in the amount of disorganized F-actin without cell elongation and microtubule alignment. These results indicate that mDia1 may coordinate microtubules and F-actin through its FH2 and FH1 regions, respectively.

Mints, Munc18-interacting proteins in synaptic vesicle exocytosis

Munc18-1 is a neuronal protein that interacts with syntaxin 1 and is required for synaptic vesicle exocytosis. We have now identified two Munc18-1-interacting proteins called Mint1 and Mint2 that may mediate the function of Munc18-1. Mint proteins are detectable only in brain and are composed of an N-terminal sequence that binds Munc18-1, a middle phosphotyrosine-binding domain, and two C-terminal PDZ domains thought to attach proteins to the plasma membrane. In brain, Mint proteins are part of a multimeric complex containing Munc18-1 and syntaxin that likely functions as an intermediate in synaptic vesicle docking/fusion. The phosphotyrosine-binding domain specifically binds to phosphatidylinositol phosphates known to be produced during vesicle exocytosis (Hay, J. C., Fisette, P. L., Jenkins, G. H., Fukami, K., Takonawa, T., Anderson, R. A., and Martin, T. F. J. (1995) Nature 374, 173-177). Our data suggest a model whereby local production of phosphatidylinositol phosphates may trigger the binding of vesicles to the active zone via the Mint.Munc18-1 complex in conjunction with syntaxin 1.

Serum uric acid and risk for development of hypertension and impaired fasting glucose or Type II diabetes in Japanese male office workers

We examined the association of serum uric acid (SUA) with development of hypertension (blood pressure > or = 140/90 mmHg and/or medication for hypertension) and impaired fasting glucose (IFG) (a fasting plasma glucose level 6.1-6.9 mmol/l) or Type II (non-insulin-dependent) diabetes (a fasting plasma glucose level > or = 7.0 mmol/l and/or medication for diabetes) over a 6-year follow-up among 2310 Japanese male office workers aged 35-59 years who did not have hypertension, IFG, Type II diabetes, or past history of cardiovascular disease at study entry. After controlling for potential predictors of hypertension and diabetes, the relative risk for hypertension compared with quintile 1 of SUA level was 1.27 [95% confidence interval (CI): 1.00-1.62] for quintile 2, 1.34 (95% CI: 1.08-1.74) for quintile 3, 1.48 (95% CI: 1.18-1.89) for quintile 4, and 1.58 (95% CI: 1.26-1.99) for quintile 5 (p for trend <0.001). The respective multivariate-adjusted relative risks for IFG or Type II diabetes compared with quintile 1 of SUA level were 1.55 (95% CI: 0.95-2.63), 1.62 (95% CI: 0.98-2.67), 1.61 (95% CI: 1.01-2.58), and 1.78 (95% CI: 1.11-2.85) (p for trend = 0.030). The association between SUA level and risk for hypertension and IFG or Type II diabetes was stronger among men with a body mass index (BMI) <24.2 kg/m2 than among men with a BMI > or = 24.2 kg/m2, although the absolute risk was greater in more obese men. These results indicate that SUA level is closely associated with an increased risk for hypertension and IFG or Type II diabetes.

Direct interaction of the rat unc-13 homologue Munc13-1 with the N terminus of syntaxin

unc-13 mutants in Caenorhabditis elegans are characterized by a severe deficit in neurotransmitter release. Their phenotype is similar to that of the C. elegans unc-18 mutation, which is thought to affect synaptic vesicle docking to the active zone. This suggests a crucial role for the unc-13 gene product in the mediation or regulation of synaptic vesicle exocytosis. Munc13-1 is one of three closely related rat homologues of unc-13. Based on the high degree of similarity between unc-13 and Munc13 proteins, it is thought that their essential function has been conserved from C. elegans to mammals. Munc13-1 is a brain-specific peripheral membrane protein with multiple regulatory domains that may mediate diacylglycerol, phospholipid, and calcium binding. In the present study, we demonstrate by three independent methods that the C terminus of Munc13-1 interacts directly with a putative coiled coil domain in the N-terminal part of syntaxin. Syntaxin is a component of the exocytotic synaptic core complex, a heterotrimeric protein complex with an essential role in transmitter release. Through this interaction, Munc13-1 binds to a subpopulation of the exocytotic core complex containing synaptobrevin, SNAP25 (synaptosomal-associated protein of 25 kDa), and syntaxin, but to no other tested syntaxin-interacting or core complex-interacting protein. The site of interaction in syntaxin is similar to the binding site for the unc-18 homologue Munc18, but different from that of all other known syntaxin interactors. These data indicate that unc-13-related proteins may indeed be involved in the mediation or regulation of synaptic vesicle exocytosis by modulating or regulating core complex formation. The similarity between the unc-13 and unc-18 phenotypes is paralleled by the coincidence of the binding sites for Munc13-1 and Munc18 in syntaxin. It is possible that the phenotype of unc-13 and unc-18 mutations is caused by the inability of the respective mutated gene products to bind to syntaxin.

Antigen-induced apoptotic death of Ly-1 B cells responsible for autoimmune disease in transgenic mice

Studies on transgenic mice expressing immunoglobulins against self-antigens have shown that self-tolerance is maintained by active elimination (clonal deletion), functional inactivation (clonal anergy) of self-reactive B cells, or a combination of both. We have established and characterized a transgenic mouse line expressing an anti-erythrocyte autoantibody. In contrast to other autoantibody transgenic lines, about 50% of the animals of this transgenic line suffer from autoimmune disease, indicating a loss of self-tolerance. Here we show that peritoneal Ly-1 B cells (also known as B-1 cells) are responsible for this autoimmune disease in our transgenic mice. A few self-reactive Ly-1 B cells that have somehow escaped the deletion mechanism expand in the peritoneum because of the absence of self-antigen. These Ly-1 B cells are eliminated in vivo by apoptosis once exposed to self-antigen. On the basis of these results we propose a novel autoantibody production mechanism whereby self-reactive B cells sequestered in compartments free of self-antigens may survive, proliferate and be activated for generation of pathogenic autoantibodies in autoimmune diseases.

Clinical applications of a new type of real-time two-dimensional Doppler flow imaging system

The clinical significance of a newly developed real-time 2-dimensional (2-D) Doppler flow imaging technique was assessed. In the instrumentation of the echocardiograph, the pulsed Doppler mechanism was incorporated in a wide-angle, phased-array system. The Doppler flow signals obtained from the cardiac chamber were processed on the basis of the autocorrelation principle. The direction, velocity and variance of the intracardiac blood flow were calculated in real time and displayed in the color-coded mode on the television screen, and were superimposed on the 2-D echocardiographic image of the heart. The technique was used in 20 healthy subjects and 100 cardiac patients. The new technique clearly visualized the whole aspect of intracardiac blood flow by the cine mode in real time; thus, the technique may be called Doppler cineangiocardiography. The mitral inflow and the aortic ejection flow were clearly demonstrated. A regurgitant jet from the valve orifices was dynamically visualized as seen in the cineangiogram. The spatial orientation and extent of the regurgitant jet were easily assessed. The jet stream through the stenotic mitral orifice was well imaged in the left ventricular cavity, showing a variety of stream directions. Intracardiac shunts in ventricular septal defect and atrial septal defect were clearly visualized. The defect could be localized on the interventricular septum on the basis of the site where the shunt flow spurted, although the echocardiographic interruption was not demonstrated in the 2-D echocardiographic image of the cardiac structure. Although some technical problems remain, our new technique greatly improves the diagnostic efficacy of ultrasound.

Hepatocyte growth factor prevents renal fibrosis and dysfunction in a mouse model of chronic renal disease

Chronic renal disease (CRD) is generally thought to be incurable, except through renal transplantation, and the number of patients with CRD is on the increase. Glomerulosclerosis and tubulointerstitial fibrosis represent the morphological equivalent of end-stage CRD. In this study, we demonstrated the preventive effect of hepatocyte growth factor (HGF) on the progression of renal dysfunction and fibrosis, using a spontaneous mouse model for CRD (ICGN strain). The mice progressively developed glomerular sclerotic injury, tubular atrophy, and renal dysfunction until they were 17 wk of age. When recombinant HGF was injected into these mice during a 4-wk-period (from weeks 14-17 after birth), DNA synthesis of tubular epithelial cells was found to be 4.4-fold higher than in mice without HGF injection, thereby suggesting tubular parenchymal expansion promoted by HGF. Notably, HGF suppressed the expression of transforming growth factor-beta and of platelet-derived growth factor as well as myofibroblast formation in the affected kidney. Consequently, the onset of tubulointerstitial fibrosis was almost completely inhibited by HGF, while HGF attenuated the progression of glomerulosclerosis, both leading to preventing manifestation of renal dysfunction. From our results, supplement therapy with HGF may be taken into consideration as a novel option for prevention and treatment of CRD.

Evaluation of tricuspid regurgitation by pulsed Doppler and two-dimensional echocardiography

We analyzed tricuspid regurgitation noninvasively using ultrasonic pulsed Doppler and two-dimensional echocardiography in 66 patients in whom tricuspid regurgitation was suspected from routine clinical evaluation. All of the patients also underwent right ventriculography. Ten healthy subjects served as controls. In 62 of 66 patients, the study was adequately performed. In 58 of 62 patients, pansystolic abnormal Doppler signals were detected in the right atrial cavity, and were interpreted to indicate tricuspid regurgitant flow. Two-dimensional echocardiograms in the parasternal four-chamber view demonstrated that the region in which the abnormal Doppler signals were detected was spindle-shaped and extended from the tricuspid orifice toward the right atrial posterior wall parallel to the interatrial septum. The severity of regurgitation was graded on a four-point scale, based on the distance reached by the abnormal signals from the tricuspid orifice toward the posterior wall. For comparison, the right ventriculograms were evaluated on a four-point scale similar to the Sellers classification of mitral regurgitation. The grades by the two methods matched exactly in 36 cases, differed by one level in 23 and by two levels in three. Thus, the two methods showed a good correspondence. Similar results were obtained for the grading based on the area covered by the abnormal signals. We conclude that noninvasive grading of tricuspid regurgitation by ultrasonic pulsed Doppler and two-dimensional echocardiography is practicable.

A transgenic model of autoimmune hemolytic anemia

We made double transgenic mice bearing immunoglobulin heavy and light chain genes encoding an autoantibody against the mouse erythrocyte by the cross of C57BL/6 mice carrying the transgene for each chain of the immunoglobulin. Although no obvious disorders were found in the single-chain transgenic mice, severely anemic symptoms were found in some of the double transgenic mice, in which most B cells express, at least on their surface, the autoantibody reactive to self-antigens on the erythrocyte. Individual double-transgenic mice showed a wide variation of phenotypes between severe anemia and no symptoms. Both deletion and anergy of autoreactive B cells were seen in each individual mouse, but their relative contribution to self-tolerance was variable and not directly related to the severity of anemia or the amount of the autoantibody produced. This transgenic system provides a good autoimmune disease model for exploring its onset mechanism, and means of its treatment and prevention.

Anticonvulsant action of a non-competitive antagonist of NMDA receptors (MK-801) in the kindling model of epilepsy

Anticonvulsant action of MK-801, a novel non-competitive antagonist of N-methyl-D-aspartate (NMDA) receptors, was investigated in the kindling model of epilepsy in rats. The results obtained were as follows. (1) Both the seizure stage and afterdischarge duration of previously kindled seizures from the amygdala were significantly suppressed following systemic injection of MK-801 (0.25-4 mg/kg) in a dose-dependent manner. The maximum effects were observed between 2 and 4 after the injection. (2) The MK-801 also showed significant anticonvulsant effects on kindled seizures from the frontal cortex and the ventral and dorsal hippocampus. The efficacy, however, significantly differed between these kindled sites. (3) Daily treatment of MK-801 (0.25 and 1 mg/kg) prior to each electrical stimulation of the amygdala significantly retarded kindling seizure development and increased the total amount of afterdischarge (accumulated AD) required to reach the first stage 5 seizure. During drug sessions of 1 mg/kg MK-801 for 19 days, all rats showed only partial seizures and the growth of afterdischarge was strongly prevented. (4) Pretreatment with reserpine did not antagonize the anticonvulsant effects of MK-801 on previously kindled seizures from the amygdala, suggesting that the effects may not be mediated by catecholaminergic systems. These results indicate that MK-801 has potent anticonvulsant actions on kindled seizures from both limbic and cortical foci, the NMDA system may play a critical role in the seizure-triggering mechanism of kindling. The possible application of NMDA antagonists in clinical epilepsy is suggested.

Induction of DNA damage by dimethylarsine, a metabolite of inorganic arsenics, is for the major part likely due to its peroxyl radical

To reveal the mechanisms of previously reported lung-specific DNA strand scissions in murine after oral administration of dimethylarsinic acid (DMAA), a main metabolite of inorganic arsenics in mammals, the ultimate substance causing DNA lesion was investigated using dimethylarsine which was a further metabolite of DMAA. The alkaline elution assay using 3H-labeled DNA showed that a major portion of the strand breaks was not suppressed by SOD and catalase, suggesting an ultimate substance other than active oxygen participated in the DNA damage. By ESR analysis, a radical estimated to be (CH3)2AsOO. was detected as a reaction product of dimethylarsine and molecular oxygen. This peroxyl radical, rather than active oxygen, was assumed to play a major role in DNA damage.

Periostin, a matrix protein, is a novel biomarker for idiopathic interstitial pneumonias

Idiopathic interstitial pneumonias (IIPs) are histopathologically classified into several types, including usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP) and cryptogenic organising pneumonia (COP). We investigated whether periostin, a matrix protein, could be used as a biomarker to assess histopathological types of IIPs. We performed immunohistochemical analyses in each histopathological type of IIP, examined serum levels of periostin in IIP patients and analysed the relationship between serum levels of periostin and the pulmonary functions in patients with idiopathic pulmonary fibrosis (IPF). Periostin was strongly expressed in lungs of UIP and fibrotic NSIP patients, whereas expression of periostin was weak in the lungs of cellular NSIP and COP patients, as well as in normal lungs. Serum levels of periostin in IPF were significantly higher than those of healthy subjects and COP patients. Furthermore, periostin levels in IPF patients were inversely correlated with their pulmonary functions. Thus, we have found that periostin is a novel component of fibrosis in IIP. Periostin may be a potential biomarker to distinguish IIP with fibrosis.

Discovery of novel, potent, and selective small-molecule CCR5 antagonists as anti-HIV-1 agents: synthesis and biological evaluation of anilide derivatives with a quaternary ammonium moiety

The search for new small-molecule CCR5 antagonists by high-throughput screening (HTS) of the Takeda chemical library using [(125)I]RANTES and CHO/CCR5 cells led to the discovery of lead compounds (A, B) with a quaternary ammonium or phosphonium moiety, which were synthesized to investigate new MCP-1 receptor antagonists. A series of novel anilide derivatives 1 with a quaternary ammonium moiety were designed, synthesized, and tested for their CCR5 antagonistic activity. Through the optimization of lead compounds, we have found N,N-dimethyl-N-[4-[[[2-(4-methylphenyl)-6, 7-dihydro-5H-benzocyclohepten-8-yl]carbonyl]amino]benzyl]tetrahydr o-2 H-pyran-4-aminium chloride (1r, TAK-779) as a highly potent and selective nonpeptide CCR5 antagonist with a IC(50) value of 1.4 nM in the binding assay. Compound 1r also inhibited the replication of macrophage (M)-tropic HIV-1 (Ba-L strain) in both MAGI-CCR5 cells and PBMCs with EC(50) values of 1.2 and 3.7 nM, respectively. The synthesis and structure-activity relationships of 1r and its related compounds are detailed.

Aerodynamic characteristics of the wings and body of a dragonfly

The aerodynamic characteristics of the wings and body of a dragonfly and of artificial wing models were studied by conducting two types of wind-tunnel tests and a number of free-flight tests of gliders made using dragonfly wings. The results were consistent between these different tests. The effects of camber, thickness, sharpness of the leading edge and surface roughness on the aerodynamic characteristics of the wings were characterized in the flow field with Reynolds numbers (Re) as low as 103 to 104.

Regulation of a putative high-affinity nitrate transporter (Nrt2;1At) in roots of Arabidopsis thaliana

Putative high-affinity nitrate (NO3-) transporter genes, designated Nrt2;1At and Nrt2;2At, were isolated from Arabidopsis thaliana by RT-PCR using degenerate primers. The genes shared 86% and 89% identity at the amino acid and nucleotide levels, respectively, while their proteins shared 30-73% identities with other eukaryotic high-affinity NO3- transporters. Both genes were induced by NO3-, but Nrt2;1At gene expression was not apparent in 2- and 5-day-old plants. By 10 days, and thereafter, Nrt2;1At gene expression in roots was substantially higher than for the Nrt2;2At gene. Root Nrt2;1At expression levels were strongly correlated with inducible high-affinity 13NO3- influx into intact roots under several treatment conditions. The use of inhibitors of N assimilation indicated that downregulation of Nrt2;1At expression was mediated by NH4+, gln and other amino acids.

Oral administration of lipopolysaccharides activates B-1 cells in the peritoneal cavity and lamina propria of the gut and induces autoimmune symptoms in an autoantibody transgenic mouse

About a half of the antierythrocyte autoantibody transgenic (autoAb Tg) mice, in which almost all B cells are detected in the spleen, lymph nodes, and Peyer's patches, but not in the peritoneal cavity, suffer from autoimmune hemolytic anemia. The occurrence of this disease is strongly linked to production of autoAb by activated peritoneal B-1 cells in the Tg mice. In this study, we have shown that oral administration of lipopolysaccharides (LPS) activated B-1 cells in the lamina propria of the gut as well as the peritoneal cavity in the healthy Tg mice and induced the autoimmune symptoms in all the Tg mice. The activation of peritoneal and lamina propria B-1 cells by enteric LPS is found not only in the anti-RBC autoAb Tg mice and normal mice but also in the aly mice which congenitally lack lymph nodes and Peyer's patches. These results suggest that B-1 cells in the two locations may form a common pool independent of Peyer's patches and lymph nodes, and can be activated by enteric thymus-independent antigens or polyclonal activators such as LPS. The induction of autoimmune hemolytic anemia in the Tg mice by enteric LPS through the activation of B-1 cells in the lamina propria of gut and in the peritoneal cavity suggests that B-1 cells and bacterial infection may play a pathogenic role in the onset of autoimmune diseases.

EHSH1/intersectin, a protein that contains EH and SH3 domains and binds to dynamin and SNAP-25. A protein connection between exocytosis and endocytosis?

In yeast two-hybrid screens for proteins that bind to SNAP-25 and may be involved in exocytosis, we isolated a protein called EHSH1 (for EH domain/SH3 domain-containing protein). Cloning of full-length cDNAs revealed that EHSH1 is composed of an N-terminal region with two EH domains, a central region that is enriched in lysine, leucine, glutamate, arginine, and glutamine (KLERQ domain), and a C-terminal region comprised of five SH3 domains. The third SH3 domain is alternatively spliced. Data bank searches demonstrated that EHSH1 is very similar to Xenopus and human intersectins and to human SH3P17. In addition, we identified expressed sequence tags that encode a second isoform of EHSH1, called EHSH2. EHSH1 is abundantly expressed in brain and at lower levels in all other tissues tested. In binding studies, we found that the central KLERQ domain of EHSH1 binds to recombinant or native brain SNAP-25 and SNAP-23. The C-terminal SH3 domains, by contrast, quantitatively interact with dynamin, a protein involved in endocytosis. Dynamin strongly binds to the alternatively spliced central SH3 domain (SH3C) and the two C-terminal SH3 domains (SH3D and SH3E) but not to the N-terminal SH3 domains (SH3A and SH3B). Immunoprecipitations confirmed that both dynamin and SNAP-25 are complexed to EHSH1 in brain. Our data suggest that EHSH1/intersectin may be a novel adaptor protein that couples endocytic membrane traffic to exocytosis. The ability of multiple SH3 domains in EHSH1 to bind to dynamin suggests that EHSH1 can cluster several dynamin molecules in a manner that is regulated by alternative splicing.