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1.
Phys Rev Lett ; 131(25): 253003, 2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38181354

ABSTRACT

Muonic helium atom hyperfine structure (HFS) measurements are a sensitive tool to test the three-body atomic system and bound-state quantum electrodynamics theory, and determine fundamental constants of the negative muon magnetic moment and mass. The world's most intense pulsed negative muon beam at the Muon Science Facility of the Japan Proton Accelerator Research Complex allows improvement of previous measurements and testing further CPT invariance by comparing the magnetic moments and masses of positive and negative muons (second-generation leptons). We report new ground-state HFS measurements of muonic helium-4 atoms at a near-zero magnetic field, performed for the first time using a small admixture of CH_{4} as an electron donor to form neutral muonic helium atoms efficiently. Our analysis gives Δν=4464.980(20) MHz (4.5 ppm), which is more precise than both previous measurements at weak and high fields. The muonium ground-state HFS was also measured under the same conditions to investigate the isotopic effect on the frequency shift due to the gas density dependence in He with CH_{4} admixture and compared with previous studies. Muonium and muonic helium can be regarded as light and heavy hydrogen isotopes with an isotopic mass ratio of 36. No isotopic effect was observed within the current experimental precision.

2.
Phys Rev Lett ; 130(17): 173001, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37172243

ABSTRACT

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst) eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

3.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Article in English | MEDLINE | ID: mdl-34397250

ABSTRACT

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

4.
Ann Oncol ; 27(12): 2242-2250, 2016 12.
Article in English | MEDLINE | ID: mdl-27765756

ABSTRACT

BACKGROUND: The human IgG4 monoclonal antibody nivolumab targets programmed cell death-1 (PD-1) and promotes antitumor response by blocking the interaction of PD-1 with its ligands. This single-center phase Ib study investigated the tolerability, safety, and pharmacokinetics of nivolumab combined with standard chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients who had stage IIIB without indication for definitive radiotherapy, stage IV, or recurrent NSCLC were eligible. Regimens were nivolumab 10 mg/kg + gemcitabine/cisplatin (arm A), pemetrexed/cisplatin (arm B), paclitaxel/carboplatin/bevacizumab (arm C), or docetaxel (arm D). Regimens A, B, and D were repeated every 3 weeks for up to four cycles and regimen C was repeated for up to six cycles; nivolumab alone (arm A), with pemetrexed (arm B), bevacizumab (arm C), or docetaxel (arm D) was continued every 3 weeks as maintenance therapy until disease progression or unacceptable toxicity. Dose-limiting toxicity (DLT) was evaluated during the first treatment cycle. RESULTS: As of March 2014, six patients were enrolled in each arm. The combination of nivolumab 10 mg/kg and chemotherapy was well tolerated. DLT was observed in only one patient in arm A (alanine aminotransferase increased). Select adverse events (those with a potential immunologic cause) of any grade were observed in six, four, six, and five patients in arms A, B, C, and D, respectively. Three, three, six, and one patient achieved partial response while median progression-free survival was 6.28, 9.63 months, not reached, and 3.15 months in arms A, B, C, and D, respectively. CONCLUSIONS: Combination of nivolumab 10 mg/kg and chemotherapy showed an acceptable toxicity profile and encouraging antitumor activity in patients with advanced NSCLC. CLINICAL TRIALS NUMBER: Japanese Pharmaceutical Information Center Clinical Trials Information (JapicCTI)-132071.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Carcinoma, Non-Small-Cell Lung/drug therapy , Neoplasm Recurrence, Local/drug therapy , Adult , Aged , Antibodies, Monoclonal/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bevacizumab , Carboplatin/administration & dosage , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/radiotherapy , Cisplatin/administration & dosage , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Disease-Free Survival , Docetaxel , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Staging , Nivolumab , Paclitaxel/administration & dosage , Pemetrexed/administration & dosage , Taxoids/administration & dosage , Gemcitabine
5.
ESMO Open ; 8(6): 102030, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37852033

ABSTRACT

BACKGROUND: Immune checkpoint inhibitors (ICIs) are indicated for various cancers and are the mainstay of cancer immunotherapy. They are often associated with ICI-related pneumonitis (CIP), however, hindering a favorable clinical course. Recently, non-oncology concomitant drugs have been reported to affect the efficacy and toxicity of ICIs; however, the association between these drugs and the risk for CIP is uncertain. The aim of this study was to assess the impact of baseline concomitant drugs on CIP incidence in ICI-treated advanced cancer patients. PATIENTS AND METHODS: This was a single-center retrospective study that included a cohort of 511 patients with advanced cancer (melanoma and non-small-cell lung, head and neck, genitourinary, and other types of cancer) treated with ICIs. Univariable analysis was conducted to identify baseline co-medications associated with CIP incidence. A propensity score matching analysis was used to adjust for potential CIP risk factors, and multivariable analysis was carried out to assess the impact of the identified co-medications on CIP risk. RESULTS: Forty-seven (9.2%) patients developed CIP. In these patients, the organizing pneumonia pattern was the dominant radiological phenotype, and 42.6% had grade ≥3 CIP, including one patient with grade 5. Of the investigated baseline co-medications, the proportion of antiplatelet drugs (n = 50, 9.8%) was higher in patients with CIP (23.4% versus 8.4%). After propensity score matching, the CIP incidence was higher in patients with baseline antiplatelet drugs (22% versus 6%). Finally, baseline antiplatelet drug use was demonstrated to increase the risk for CIP incidence regardless of cancer type (hazard ratio, 3.46; 95% confidence interval 1.21-9.86). CONCLUSIONS: An association between concomitant antiplatelet drug use at baseline and an increased risk for CIP was seen in our database. This implies the importance of assessing concomitant medications for CIP risk management.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Pneumonia , Humans , Platelet Aggregation Inhibitors/adverse effects , Retrospective Studies , Pneumonia/chemically induced , Pneumonia/epidemiology
6.
J Dairy Sci ; 93(9): 4189-95, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20723693

ABSTRACT

The objective of this study was to investigate the effect of dietary supplementation with the disaccharides trehalose and cellobiose on antioxidant activity in rumen fluid, blood, and milk of dairy cows. Nine Holstein dairy cows housed in a free-stall barn were divided into 3 groups, with each group receiving a different dietary treatment (a control diet, a 1% trehalose-supplemented diet, or a 1% cellobiose-supplemented diet) following a 3x3 Latin square design. Feed intake and milk production increased in cows receiving the trehalose-supplemented diet compared with those receiving the control and cellobiose-supplemented diets. The total protozoa numbers in the rumen fluid of cows fed trehalose- or cellobiose-supplemented diets were greater than those of the control group. The C18:0 and C18:1 fatty acid content was increased in the milk of cows fed the trehalose-supplemented diet compared with that of the control group, and the C18:3n-3 fatty acid content in the milk of cows fed the cellobiose-supplemented diet was less than that of the control group. Plasma biochemical parameters were unchanged among the different treatments. In rumen fluid, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and superoxide dismutase activity were increased 2h after feeding in cows receiving the cellobiose-supplemented diet compared with the control group, and the concentration of thiobarbituric acid reactive substances in the rumen fluid of cows fed the cellobiose-supplemented diet was decreased. In contrast, the values of these parameters measured in the milk of cows fed the cellobiose-supplemented diet were no different from those of control cows. Dietary supplementation with trehalose did, however, bring about an improvement of the oxidative status of milk and blood in these animals compared with controls. These results provide the first evidence supporting the use of dietary disaccharides to decrease lipid peroxide levels and increase the antioxidant content of dairy cow milk. The findings suggest that disaccharides, particularly trehalose, might be useful as supplements for reducing oxidative stress and improving the quality of milk for human consumption, as well as possibly impairing the processes that give rise to lipid oxidation odor in dairy cow milk.


Subject(s)
Antioxidants/analysis , Dietary Supplements , Lipid Peroxides/analysis , Milk/chemistry , Trehalose/pharmacology , Animals , Cattle , Cellobiose/pharmacology , Diet/veterinary , Eating/drug effects , Eukaryota/drug effects , Fatty Acids/analysis , Female , Free Radical Scavengers/analysis , Gastric Juice/chemistry , Lactation/drug effects , Lipid Peroxidation/drug effects , Milk/drug effects , Milk/metabolism , Rumen/drug effects , Rumen/parasitology , Superoxide Dismutase/analysis
7.
J Fish Biol ; 76(1): 161-82, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20738704

ABSTRACT

The kiss1 gene product kisspeptin is now considered to be an essential regulator of the hypothalamic-pituitary-gonadal (HPG) axis in most vertebrate species. Recent findings in fishes are beginning to set a new stage for the kisspeptin study; the existence of paralogous kisspeptin genes as well as kisspeptin receptor (formerly called GPR54) genes has quite recently been reported in several fish and amphibian species. The fishes may provide excellent animal models for the study of general principles underlying the kisspeptin and kisspeptin receptor systems of vertebrates from the evolutionary viewpoint. Unlike placental and marsupial mammalian species mainly studied so far, many teleost species have two paralogous genes of kisspeptin, kiss1 and kiss2. Medaka, Oryzias latipes, in which kiss1 and kiss2 are expressed in distinctive hypothalamic neuron populations, is a good model system for the study of central regulation of reproduction. Here, the kiss1 system but not the kiss2 system shows expression dynamics strongly indicative of its direct involvement in the HPG axis regulation via its actions on GnRH1 neurons. On the other hand, the kiss1 gene is missing, and only kiss2 is expressed in some fish species. Also, there are some recent reports that Kiss2 peptide may be a potent regulator of reproduction in some fish species. The ancestral vertebrate probably already had two paralogous kiss genes, and their main function was the HPG axis regulation. In the species that retained both paralogues during evolution, either Kiss1 or Kiss2 predominantly retains its ability for the HPG axis regulation, while the other may assume new non-reproductive functions (neofunctionalization). Alternatively, both the paralogues may assume complementary functions in the HPG axis regulation (subfunctionalization). After the divergence of teleost and tetrapod lineages, either one of the two paralogues, or even both in birds, have been lost (degradation) or became a pseudogene (non-functionalization), but the remaining paralogue retained its original function of HPG axis regulation. The identification of multiple forms of kisspeptin receptors and the rather promiscuous ligand-receptor relationships has led to the further proposal that such promiscuousness may be the basis for the functional robustness of kisspeptin and kisspeptin receptor systems in the HPG axis regulation, when one or both paralogous genes are lost or functionally partitioned during evolution.


Subject(s)
Biological Evolution , Brain/metabolism , Fishes/physiology , Tumor Suppressor Proteins/metabolism , Animals , Fishes/classification , Gene Expression Regulation , Ligands , Tumor Suppressor Proteins/genetics
8.
Cancer Res ; 52(7): 1681-6, 1992 Apr 01.
Article in English | MEDLINE | ID: mdl-1348012

ABSTRACT

The VL and VH from a murine anti-idiotypic antibody that mimics ganglioside have been cloned, sequenced, and expressed as a chimeric mouse/human IgG1 antibody. The chimeric antibody retained a binding specificity indistinguishable from the original murine antibody. The VH was a member of Vgam 3.8 family. The sequences are discussed in terms of ways in which proteins may mimic ganglioside epitopes.


Subject(s)
Antibodies, Anti-Idiotypic/genetics , Gangliosides/immunology , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Light Chains/genetics , Amino Acid Sequence , Animals , Antibodies, Anti-Idiotypic/immunology , Antibodies, Anti-Idiotypic/isolation & purification , Base Sequence , Cell Line , Chimera , Cloning, Molecular , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Humans , Immunoglobulin J-Chains/genetics , Mice , Molecular Sequence Data , Multiple Myeloma/immunology , Oligodeoxyribonucleotides , Poly A/genetics , Poly A/isolation & purification , Protein Sorting Signals/genetics , RNA, Messenger/genetics , RNA, Messenger/isolation & purification , Recombinant Proteins/immunology , Recombinant Proteins/isolation & purification , Transfection
9.
J Nutr Health Aging ; 20(4): 453-7, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26999247

ABSTRACT

OBJECTIVES: Older patients receiving home medical care often have declining functional status and multiple disease conditions. It is important to identify the risk factors for care transition events in this population in order to avoid preventable transitions. In the present study, therefore, we investigated the factors associated with discontinuation of home medical care as a potentially preventable care transition event in older patients. METHODS: Baseline data for participants in the Observational study of Nagoya Elderly with HOme MEdical (ONEHOME) study and data on the mortality, institutionalization, or hospitalisation of the study participants during a 2-year follow-up period were used. Discontinuation of home care was defined as admission to a hospital for any reason, institutionalization, or death. Univariate and multivariate Cox hazard models were used to assess the association of each of the factors with the discontinuation of home care during the observational period. The covariates included in the multivariate analysis were those significantly associated with the discontinuation of home care at the level of P<0.05 in the univariate analysis. RESULTS: The univariate Cox hazard model revealed that a low hemoglobin level (< 11g/dL), low serum albumin level (< 3g/dL), higher Charlson Comorbidity Index score, and low Mini Nutritional Assessment Short Form score (< 7) were significantly associated with the discontinuation of home care. A multivariate Cox hazard model including these four factors demonstrated that all four were independently associated with home-care discontinuation. CONCLUSIONS: The present results demonstrated that anemia, hypoalbuminemia, malnourishment, and the presence of serious comorbidities were associated with the discontinuation of home medical care among low-functioning older patients.


Subject(s)
Geriatric Assessment , Home Care Services/statistics & numerical data , Hospitalization/statistics & numerical data , Aged , Aged, 80 and over , Comorbidity , Female , Follow-Up Studies , Hemoglobins/analysis , Humans , Male , Nutrition Assessment , Proportional Hazards Models , Risk Factors , Serum Albumin/analysis
10.
Oncogene ; 18(22): 3354-64, 1999 Jun 03.
Article in English | MEDLINE | ID: mdl-10362356

ABSTRACT

We have examined fibroblast growth factor (FGF) receptor-1 mediated signal transduction in differentiation of endothelial cells (EC). The activated FGFR-1 couples to Ras through two adaptor proteins, FRS2 and Shc. In FGF-2 treated proliferating EC, FRS2 as well as Shc are tyrosine phosphorylated and interact with Grb2. In contrast, in FGF-2 treated differentiating cells, Shc, but not FRS2, is engaged in Grb2-interactions. Sustained MAP kinase activity has previously been implicated in differentiation. In FGF stimulated proliferating and differentiating endothelial cells, the MAP kinase Erk2 is activated in a sustained manner. Inhibition of MEK and MAP kinase activity by PD98059 treatment of cells, still allows EC tube formation. The FGFR-1 mediates activation of protein kinase C (PKC) through direct binding and activation of phospholipase C-gamma (PLC-gamma), and has also been shown to activate the cytoplasmic tyrosine kinase Src. Treatment of the cells with the PKC inhibitor bisindolylmaleimide does not prevent tube formation. In contrast, Src kinase activity is a prerequisite for EC differentiation, since treatment of the cells with PP1, a Src family specific inhibitor, abrogates tube formation. In differentiating EC, FGF-2 induces complex formation between Src and focal adhesion kinase (FAK). These data indicate that the Ras pathway is initiated via Shc or FRS2, dependent on the cellular program. Blocking the function of Src family kinases, attenuates differentiation.


Subject(s)
Adaptor Proteins, Signal Transducing , Endothelium, Vascular/metabolism , Fibroblast Growth Factor 2/metabolism , Genes, ras , src Homology Domains , Animals , Becaplermin , Calcium-Calmodulin-Dependent Protein Kinases/drug effects , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Cell Adhesion Molecules/drug effects , Cell Adhesion Molecules/metabolism , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Division/physiology , Cell Line , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Enzyme Inhibitors/pharmacology , Fibroblast Growth Factor 2/pharmacology , Flavonoids/pharmacology , Focal Adhesion Kinase 1 , Focal Adhesion Protein-Tyrosine Kinases , GRB2 Adaptor Protein , Indoles/pharmacology , Isoenzymes/drug effects , Isoenzymes/metabolism , Maleimides/pharmacology , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Transgenic , Phospholipase C gamma , Phosphoproteins/genetics , Phosphoproteins/metabolism , Platelet-Derived Growth Factor/metabolism , Platelet-Derived Growth Factor/pharmacology , Protein Kinase C/antagonists & inhibitors , Protein Kinase C/drug effects , Protein Kinase C/metabolism , Protein-Tyrosine Kinases/drug effects , Protein-Tyrosine Kinases/metabolism , Proteins/genetics , Proteins/metabolism , Proto-Oncogene Proteins c-sis , Receptor Protein-Tyrosine Kinases/genetics , Receptor Protein-Tyrosine Kinases/metabolism , Receptor, Fibroblast Growth Factor, Type 1 , Receptors, Fibroblast Growth Factor/genetics , Receptors, Fibroblast Growth Factor/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Signal Transduction , Type C Phospholipases/drug effects , Type C Phospholipases/metabolism , ras Proteins/genetics
11.
Oncogene ; 20(52): 7610-23, 2001 Nov 15.
Article in English | MEDLINE | ID: mdl-11753639

ABSTRACT

Dysregulated cell motility is one of the major characteristics of invasion and metastatic potentials of malignant tumor cells. Here, we examined the hepatocyte growth factor (HGF)-induced cell motility of two human renal carcinoma cell lines, ACHN and VMRC-RCW. Scattering and migration was induced in ACHN in an HGF-dependent manner, whereas they were maintained in VMRC-RCW even in the absence of HGF. In VMRC-RCW, HGF receptor (HGFR) tyrosine kinase was constitutively active, and sequence analysis showed N375S, A1209G and V1290L mutations. However, transfection experiments using porcine aortic endothelial (PAE) cells demonstrated that no single mutation or combination of two or three mutations caused HGF-independent constitutive activation. Conversely, the expressed amount of receptor protein had a pivotal role in the basal kinase activity. With respect to downstream signaling molecules of HGFR in ACHN or VMRC-RCW, the Ras-MAPK pathway was downregulated, whereas phosphoinositide 3-kinase (PI3-kinase) was not further activated by HGF-treatment in VMRC-RCW cells. The PI3-kinase inhibitors, wortmannin and LY294002 strongly inhibited spontaneous migration of VMRC-RCW. One transfected PAE cell line with massive overexpression of HGFR demonstrated scattered morphology and increased PI3-kinase activity in association with increased motility, which was partially inhibited by LY294002. Taken together, our results indicate that the overexpression of HGFR causes increase in cellular motility and PI3-kinase shows the important contribution on the increased motility of renal carcinoma cells.


Subject(s)
Carcinoma, Renal Cell/enzymology , Kidney Neoplasms/enzymology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-met/metabolism , Signal Transduction , Animals , Autocrine Communication , Cell Movement , Cells, Cultured , Endothelium, Vascular/cytology , Enzyme Activation , Hepatocyte Growth Factor/metabolism , Hepatocyte Growth Factor/pharmacology , Humans , Mitogen-Activated Protein Kinases/metabolism , Neoplasm Metastasis , Phosphoinositide-3 Kinase Inhibitors , Proto-Oncogene Proteins c-met/genetics , Swine , Transfection , Tumor Cells, Cultured , ras Proteins/metabolism
12.
Arterioscler Thromb Vasc Biol ; 21(5): 765-70, 2001 May.
Article in English | MEDLINE | ID: mdl-11348872

ABSTRACT

Although the accumulation of vascular endothelial growth factor (VEGF) has been observed in human atherosclerotic lesions, the exact role of this growth factor in atherogenesis remains unknown. We hypothesized that VEGF in the vascular wall might have a preventive effect on endothelial cell damage during atherosclerosis. To test our hypothesis, we examined whether VEGF protects against the toxicity of oxidized low density lipoprotein (Ox-LDL) in cultured endothelial cells derived from bovine aortas (BAECs). Preincubation of BAECs with VEGF prevented Ox-LDL-induced toxicity in a preincubation time- and VEGF concentration-dependent manner. Addition of N(omega)-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, did not reverse the protective effect of VEGF on Ox-LDL toxicity. Incubation of BAECs with VEGF increased intracellular glutathione (GSH) content in a time-dependent manner. Combined addition of VEGF and L-buthionine sulfoximine, a GSH synthesis inhibitor, reversed both GSH levels and the protective effect of VEGF on Ox-LDL-induced cytotoxicity. Placenta growth factor, which ligates to the VEGF Flt-1 receptor but not KDR/Flk-1, failed to prevent Ox-LDL toxicity and had no effect on intracellular GSH levels. An anti-KDR antibody completely blocked these beneficial activities of VEGF. These results suggest that VEGF prevents Ox-LDL-induced endothelial cell damage via an intracellular GSH-dependent mechanism through the KDR/Flk-1 receptor.


Subject(s)
Endothelial Growth Factors/pharmacology , Endothelium, Vascular/drug effects , Glutathione/metabolism , Lipoproteins, LDL/toxicity , Lymphokines/pharmacology , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Growth Factor/metabolism , Animals , Antibodies/immunology , Arteriosclerosis/metabolism , Cattle , Cells, Cultured , Endothelium, Vascular/metabolism , Enzyme Inhibitors/pharmacology , L-Lactate Dehydrogenase/metabolism , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide/antagonists & inhibitors , Oxidation-Reduction , Receptor Protein-Tyrosine Kinases/immunology , Receptors, Growth Factor/immunology , Receptors, Vascular Endothelial Growth Factor , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
13.
Nucleosides Nucleotides Nucleic Acids ; 24(10-12): 1947-70, 2005.
Article in English | MEDLINE | ID: mdl-16438059

ABSTRACT

The synthesis of pyrazolo[4,3-d]pyrimidine nucleoside library using solid-phase parallel synthesis methodology is described. Glycosylation of the trimethylsilyl (TMS) derivative of 1- and 2-(methyl)-1H and 2H-pyrazolo[4,3-d]pyrimidine-5,7-(4H, 6H)-dione (5) with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose in the presence of TMS triflate provided two novel protected nucleosides 6 and 7. The structures of 6 and 7 were assigned by 1H and 2D NMR experiments. Nucleosides 6 and 7 were then transformed to the key intermediates 12 and 15 respectively. Reaction of 12 and 15 with MMTCl resin in the presence of 2,6-lutidine afforded the necessary scaffolds B and C. Different amines (96) were introduced selectively by nucleophilic substitution on scaffolds B and C using solid-phase parallel semi-automated synthesizer. Cleavage of the products from the solid support with 30% HFIP in a parallel fashion yielded nucleoside libraries simultaneously, and they were analyzed and characterized by high-throughput LC-MS.


Subject(s)
Allopurinol/analogs & derivatives , Ribonucleosides/chemical synthesis , Allopurinol/chemical synthesis , Allopurinol/chemistry , Molecular Structure , Ribonucleosides/chemistry
14.
Neurology ; 35(7): 998-1002, 1985 Jul.
Article in English | MEDLINE | ID: mdl-4010967

ABSTRACT

In six patients with CT evidence of posterior thalamic hemorrhage, we found the following signs: saccadic hypometria away from the lesion; defective pursuit toward the lesion with corresponding opticokinetic abnormalities; mild ipsilateral ptosis; ipsilateral miosis; unilateral sensory neglect; and sensorimotor hemiparesis. This distinct syndrome has a benign course and satisfactory recovery. It differs from the classic picture of thalamic hemorrhage, and can be called "the syndrome of posterior thalamic hemorrhage."


Subject(s)
Cerebral Hemorrhage/diagnostic imaging , Thalamic Diseases/diagnostic imaging , Aged , Cerebral Hemorrhage/pathology , Eye Movements , Female , Fixation, Ocular , Humans , Male , Middle Aged , Radiography , Syndrome , Thalamic Diseases/pathology , Visual Pathways/pathology
15.
Eur J Cancer ; 35(6): 1003-8, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10533485

ABSTRACT

Epidemiological and clinical studies imply that retinoids have a chemopreventative action against cancer and can suppress the growth of cancer cells. The regulation of connexin (Cx) expression by retinoids varies among tissues and organs. In this study, we investigated whether all-trans retinoic acid (ATRA) upregulates gap junctional intercellular communication (GJIC) in renal epithelial cells exposed to renal carcinogens. Madin Darby canine kidney (MDCK) cells were incubated with ATRA for 3 days, then briefly exposed to 12-O-tetradecanoyl-phorbol-13-acetate (TPA) or renal carcinogens potassium bromate (KBrO3) and dimethylnitrosamine (DMN). ATRA increased the expression of connexin 43 mRNA and protein without affecting Cx 43 phosphorylation and prevented inadequate Cx 43 localisation caused by TPA/KBrO3 or DMN. Consequently, ATRA prevented the disruption of GJIC in MDCK cells. These data suggest that ATRA enhanced GJIC by upregulating Cx 43 expression and that ATRA might be useful for prevention of renal cell carcinoma.


Subject(s)
Carcinogens/pharmacology , Cell Communication/drug effects , Gap Junctions/drug effects , Tretinoin/pharmacology , Blotting, Western , Cell Communication/physiology , Cell Division , Cells, Cultured , Epithelial Cells/cytology , Fluorescent Antibody Technique , Gap Junctions/physiology , Humans
16.
Atherosclerosis ; 155(2): 321-7, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11254902

ABSTRACT

Although Rho, a small GTPase, has been demonstrated to play an important role in the smooth muscle contraction and relaxation, little is known about the involvement of Rho protein in smooth muscle cell (SMC) migration. In this study the role of Rho-Rho kinase pathway was examined in SMC migration induced by platelet-derived growth factor (PDGF) and lysophosphatidic acid (LPA). C3 transferase, a specific inhibitor of Rho, blocked SMC migration induced by PDGF and LPA. Y-27632, a specific inhibitor of Rho kinase, a direct target molecule of Rho, inhibited PDGF and LPA-induced SMC migration in a concentration dependent manner. Although rapid increase in myosin light chain (MLC) phosphorylation in SMC treated with LPA was observed, no enhanced MLC phosphorylation was detected in response to PDGF. Y-27632 suppressed LPA-induced as well as basal level of MLC phosphorylation. ML-9, a specific inhibitor of myosin light chain kinase (MLCK), inhibited PDGF and LPA-induced SMC migration without the suppression of MLC phosphorylation at 5 min incubation, suggesting that MLCK may contribute to SMC migration via mechanism other than MLC phosphorylation. These results suggest that Rho-Rho kinase pathway is implicated in SMC migration and that different signaling pathways downstream of Rho-Rho kinase may be involved in LPA and PDGF-induced SMC migration. MLC phosphorylation via Rho-Rho kinase pathway appears to be implicated in LPA-dependent SMC migration. Whereas PDGF-mediated SMC migration is independent of increased MLC phosphorylation and other target molecules downstream of Rho-Rho kinase seem to be involved.


Subject(s)
Muscle, Smooth, Vascular/cytology , Myosin-Light-Chain Kinase/physiology , Protein Processing, Post-Translational , Protein Serine-Threonine Kinases/physiology , Signal Transduction/drug effects , Tunica Media/cytology , rho GTP-Binding Proteins/physiology , Amides/pharmacology , Animals , Aorta/cytology , Azepines/pharmacology , Cattle , Cell Adhesion , Cell Movement/drug effects , Enzyme Inhibitors/pharmacology , Intracellular Signaling Peptides and Proteins , Lysophospholipids/pharmacology , Muscle, Smooth, Vascular/drug effects , Phosphorylation/drug effects , Platelet-Derived Growth Factor/pharmacology , Protein Processing, Post-Translational/drug effects , Protein Serine-Threonine Kinases/antagonists & inhibitors , Pyridines/pharmacology , rho-Associated Kinases
17.
Neuroscience ; 97(2): 279-84, 2000.
Article in English | MEDLINE | ID: mdl-10799759

ABSTRACT

alpha-Synuclein is a key component of Lewy bodies found in the brains of patients with Parkinson's disease and two point mutations in this protein, Ala53Thr and Ala30Pro, are associated with rare familial forms of the disease. Several lines of evidence suggest the involvement of oxidative stress in the pathogenesis of nigral neuronal death in Parkinson's disease. In the present work we studied the effects of changes in the alpha-synuclein sequence on the susceptibility of cells to reactive oxygen species. Human dopaminergic neuroblastoma SH-SY5Y cells were stably transduced with various isoforms of alpha-synuclein and their survival following exposure to hydrogen peroxide or to the dopaminergic neurotoxin MPP(+) was assessed. Cells expressing the two point mutant isoforms of alpha-synuclein were significantly more vulnerable to oxidative stress, with the Ala53Thr engineered cells faring the worst. In addition, cells expressing C-terminally truncated alpha-synuclein, particularly the 1-120 residue protein, were more susceptible than control beta-galactosidase engineered cells. The present experiments indicate that point mutations and C-terminal truncation of alpha-synuclein exaggerate the susceptibility of dopaminergic cells to oxidative damage. Thus, these observations provide a pathogenetic link between alpha-synuclein aberrations and a putative cell death mechanism in Parkinson's disease.


Subject(s)
Brain/metabolism , Nerve Tissue Proteins/physiology , Oxidative Stress , 1-Methyl-4-phenylpyridinium/toxicity , Amino Acid Substitution , Cell Survival/drug effects , Humans , Hydrogen Peroxide/pharmacology , Mutagenesis, Site-Directed , Nerve Tissue Proteins/chemistry , Nerve Tissue Proteins/genetics , Neuroblastoma , Oxidative Stress/drug effects , Phosphoproteins/physiology , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Deletion , Synucleins , Transfection , Tumor Cells, Cultured , alpha-Synuclein
18.
Cancer Lett ; 69(2): 85-91, 1993 Apr 30.
Article in English | MEDLINE | ID: mdl-7684317

ABSTRACT

A study was conducted on the effect of vinblastine (VBL), an anti-mitotic drug that is commonly employed in the treatment of human renal cell carcinoma. When VBL was added to serum-free cultures of the ACHN and NT cell lines (both lines are of human renal carcinoma origin), a concentration of 1 microgram/ml resulted in death of most of the cells of both cell types. However, at a concentration of 10 ng/ml or less, although the cells detached from the culture dish, many viable cells were observed. In addition, in an in vitro invasion assay, the invasiveness of these detached cells was demonstrated to be accelerated in comparison with the parent monolayed cells. This increase of invasion was observed in the treatment of TN-16 which is known to have a metaphase-arresting effect, not to have an anti-cancer effect. When detached cells by VBL were inoculated into soft agar, their colony-forming ability was clearly increased in comparison with the parent cells or TN-16 treated cells. These results indicate that low concentration of VBL appears to increase the malignant potential of human renal carcinoma cells in culture.


Subject(s)
Carcinoma, Renal Cell/pathology , Cell Adhesion/drug effects , Cell Division/drug effects , Neoplasm Invasiveness , Vinblastine/administration & dosage , Aprotinin/pharmacology , Dose-Response Relationship, Drug , Fibronectins/metabolism , Humans , In Vitro Techniques , Metaphase/drug effects , Pyrrolidinones/pharmacology , Tumor Cells, Cultured/drug effects
19.
J Endocrinol ; 166(3): 545-51, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10974649

ABSTRACT

Oscillation of insulin release by the pancreatic islets was evaluated under stringent Ca(2+)-free conditions for the first time. Isolated single rat islets were exposed to 16.7 mM glucose in the presence of 1.9 mM Ca(2+), or under the stringent Ca(2+)-free conditions (Ca(2+) omission with 1 mM EGTA, 6 microM forskolin and 100 nM phorbol 12-myristate 13-acetate). Fifteen minutes after the initiation of glucose stimulation, effluent was collected at a 6-s interval, insulin was determined in duplicate by a highly sensitive insulin radioimmunoassay, and oscillation and pulsatility of release statistically analyzed. Significant oscillation of insulin release was observed in all islets irrespective of presence and absence of Ca(2+). Significant pulsatility of release was detected in 7 of 11 islets in the presence of Ca(2+) and three of six isl! ets in the absence of Ca(2+). In conclusion, high glucose elicits oscillatory insulin release both in the presence and absence of extracellular Ca(2+).


Subject(s)
Calcium/metabolism , Glucose/pharmacology , Insulin/metabolism , Islets of Langerhans/metabolism , Animals , Cells, Cultured , Insulin Secretion , Male , Rats , Rats, Wistar , Secretory Rate
20.
Hum Pathol ; 25(2): 198-202, 1994 Feb.
Article in English | MEDLINE | ID: mdl-7907076

ABSTRACT

The proliferative activity of dysplasia and carcinoma in situ (CIS) in the uterine cervix was examined using proliferating cell nuclear antigen (PCNA) immunostaining and silver-binding argyrophilic nucleolar organizer region (AgNOR) staining. A significant difference in the labeling index of PCNA immunostaining obtained from dysplastic cells in each histopathologic category was demonstrated between severe dysplasia and CIS. There was no significant difference among each category of dysplasia. The frequency of mitotic figures was highest in CIS, followed in decreasing order by severe, moderate, and mild dysplasia, and was closely correlated with the histopathologic classification. There was an intimate correlation between the PCNA and mitotic indexes in severe dysplasia and CIS. However, the mean numbers of AgNORs in each category of dysplasia and CIS were not significantly different, and there was no apparent relationship with the histologic classification. The PCNA index seemed to be a useful means of evaluating proliferative activity in dysplasia and CIS, and especially in distinguishing CIS from severe dysplasia. In addition, the present PCNA index suggests that a considerable alteration of the biologic behavior involving genetic changes occurs during the progression of carcinogenesis from severe dysplasia to CIS. However, AgNOR staining did not appear to reliably represent the proliferative activity in these lesions.


Subject(s)
Carcinoma in Situ/pathology , Nuclear Proteins/analysis , Nucleolus Organizer Region/pathology , Uterine Cervical Dysplasia/pathology , Uterine Cervical Neoplasms/pathology , Antigens, Neoplasm/analysis , Carcinoma in Situ/immunology , Cell Division , Female , Humans , Immunohistochemistry , Mitotic Index , Proliferating Cell Nuclear Antigen , Silver Staining , Uterine Cervical Dysplasia/immunology , Uterine Cervical Neoplasms/immunology
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