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1.
Scand J Rheumatol ; 44(3): 247-52, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25351965

RESUMEN

OBJECTIVES: To establish the optimal inflammation control of Kawasaki disease (KD), we investigated the clinical and pathophysiological basis of pericardial effusion (PE) during the acute phase of KD. METHOD: Clinical and laboratory features of Japanese KD children with PE (PE group: n = 9) and without PE (non-PE group: n = 89) were studied retrospectively by using the medical records. Serum levels of soluble tumour necrosis factor receptor 1 (sTNFR1), interleukin 6 (IL-6), and vascular endothelial growth factor (VEGF) were assessed by enzyme-linked immunosorbent assays (ELISAs). RESULTS: PE group patients had coronary artery lesions (CALs) more frequently than non-PE group patients during the acute phase of KD (33% vs. 5.6%, p = 0.024). PE patients also showed lower levels of haemoglobin (p < 0.01) and serum albumin (p < 0.01) and higher platelet counts (p = 0.013) than non-PE patients. The proportion of neurological symptoms, but not other manifestations, in the PE group was higher than in the non-PE group (p = 0.022). All patients survived free from coronary artery aneurisms. Serum levels of sTNFR1, but not the other cytokines, in the PE group were higher than those in the non-PE group (p < 0.001). The sTNFR1 levels correlated positively with C-reactive protein (CRP) (r = 0.30, p = 0.019) or total bilirubin (r = 0.40, p < 0.01) levels. CONCLUSIONS: Acute PE in KD patients indicated the severity of TNF-mediated vascular inflammation and concurrent CALs. According to the progression, these patients might need more targeted therapy of anti-inflammation for a better coronary outcome.


Asunto(s)
Aneurisma Coronario/sangre , Síndrome Mucocutáneo Linfonodular/sangre , Derrame Pericárdico/sangre , Proteína C-Reactiva/metabolismo , Niño , Preescolar , Aneurisma Coronario/diagnóstico por imagen , Aneurisma Coronario/etiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Hemoglobinas , Humanos , Lactante , Interleucina-6/sangre , Masculino , Síndrome Mucocutáneo Linfonodular/complicaciones , Derrame Pericárdico/diagnóstico por imagen , Derrame Pericárdico/etiología , Recuento de Plaquetas , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Estudios Retrospectivos , Albúmina Sérica , Ultrasonografía , Factor A de Crecimiento Endotelial Vascular/sangre
2.
Surg Today ; 45(8): 986-92, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25156007

RESUMEN

PURPOSE: To estimate the feasibility and limitations of incomplete cytoreductive surgery and modern systemic chemotherapy in patients with synchronous peritoneal carcinomatosis from colorectal cancer and to identify risk factors for death and factors associated with the patient prognosis. METHODS: Sixty-five consecutive patients underwent surgery for synchronous peritoneal carcinomatosis from colorectal cancer at Hiroshima University, Japan between 1992 and 2012. The clinical, histological, and survival data were analyzed for independent risk factors and prognostic factors. The patients were retrospectively stratified into two groups according to the extent of surgery: complete cytoreductive surgery or incomplete cytoreductive surgery. RESULTS: The median survival times in the complete and incomplete cytoreductive surgery groups were 29.8 and 10.0 months, respectively. Receiving systemic chemotherapy alone was an independent risk factor for death in the incomplete cytoreductive surgery group (P < 0.001). Oxaliplatin and molecular-targeted drug (cetuximab or bevacizumab) therapies were also independent prognostic factors (P < 0.001), whereas irinotecan therapy was not a prognostic factor (P = 0.494). CONCLUSION: Oxaliplatin and molecular-targeted drug therapies improved the overall survival in patients undergoing incomplete cytoreductive surgery. Future trials for patients with synchronous peritoneal carcinomatosis from colorectal cancer should be undertaken, with patients stratified according to treatment with complete cytoreductive surgery or incomplete cytoreductive surgery with modern chemotherapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/terapia , Procedimientos Quirúrgicos de Citorreducción/métodos , Terapia Molecular Dirigida , Neoplasias Primarias Múltiples , Compuestos Organoplatinos/uso terapéutico , Neoplasias Peritoneales/terapia , Anciano , Neoplasias Colorrectales/mortalidad , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Oxaliplatino , Neoplasias Peritoneales/mortalidad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
3.
Soft Matter ; 10(37): 7165-9, 2014 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25097044

RESUMEN

A new structural design is proposed for wrinkling to improve mechanical durability by exploiting a porous polymer film embedded on the surface of an elastomer, which acts as a hard layer, buckles into wrinkles and effectively suppresses fatal failures such as delamination and cracking.

4.
Chemosphere ; 346: 140486, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37875216

RESUMEN

Nitrogen dioxide (NO2) is one of the toxic gases produced by chemical industries, power plants, and vehicles. In this work, we demonstrate an inexpensive sensing platform for NO2 detection at room temperature (RT-32 °C) based on a charge transfer mechanism. Three-dimensional hierarchical SnS2 and SnS2/mesoporous TiO2 nanocomposites were synthesized via the solvothermal method. SnS2/20 wt% mesoporous TiO2 nanocomposites sample showed 245.4% enhanced response compared to pristine SnS2. The fabricated device exhibits excellent selectivity among all other interfering gases with one-month stability. The rapid response and enhanced response achieved were obtained for the minimum concentration of 2 ppm NO2. The formation of heterojunction between SnS2 and mesoporous TiO2 has a synergetic effect, providing more active sites and porous structures for the detection of NO2 gas molecules.


Asunto(s)
Industria Química , Dióxido de Nitrógeno , Temperatura , Gases
5.
Proc Natl Acad Sci U S A ; 107(17): 7680-5, 2010 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-20388903

RESUMEN

The recent assembly of the silkworm Bombyx mori genome with 432 Mb on 28 holocentric chromosomes has become a reference in the genomic analysis of the very diverse Order of Lepidoptera. We sequenced BACs from two major pests, the noctuid moths Helicoverpa armigera and Spodoptera frugiperda, corresponding to 15 regions distributed on 11 B. mori chromosomes, each BAC/region being anchored by known orthologous gene(s) to analyze syntenic relationships and genome rearrangements among the three species. Nearly 300 genes and numerous transposable elements were identified, with long interspersed nuclear elements and terminal inverted repeats the most abundant transposable element classes. There was a high degree of synteny conservation between B. mori and the two noctuid species. Conserved syntenic blocks of identified genes were very small, however, approximately 1.3 genes per block between B. mori and the two noctuid species and 2.0 genes per block between S. frugiperda and H. armigera. This corresponds to approximately two chromosome breaks per Mb DNA per My. This is a much higher evolution rate than among species of the Drosophila genus and may be related to the holocentric nature of the lepidopteran genomes. We report a large cluster of eight members of the aminopeptidase N gene family that we estimate to have been present since the Jurassic. In contrast, several clusters of cytochrome P450 genes showed multiple lineage-specific duplication events, in particular in the lepidopteran CYP9A subfamily. Our study highlights the value of the silkworm genome as a reference in lepidopteran comparative genomics.


Asunto(s)
Cromosomas/genética , Evolución Molecular , Genes de Insecto/genética , Mariposas Nocturnas/genética , Sintenía/genética , Animales , Secuencia de Bases , Antígenos CD13/genética , Cromosomas Artificiales Bacterianos/genética , Análisis por Conglomerados , Genómica/métodos , Datos de Secuencia Molecular , Familia de Multigenes/genética , Análisis de Secuencia de ADN
6.
Clin Exp Immunol ; 169(1): 33-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22670776

RESUMEN

Intravenous immunoglobulin (IVIG) produces a rapid and prolonged increase in the platelet counts of children with immune thrombocytopenia (ITP). The mechanism of IVIG efficacy in a murine model of ITP has been reported to operate through an IVIG-mediated increase in the expression of the inhibitory Fc receptor FcγRIIB(CD32B) on splenic macrophages. This investigation examined whether IVIG administration results in a similar increase in FcγRIIB expression on peripheral blood CD14(+) monocytes in 20 children with ITP. FcγRIIB expression on peripheral blood monocytes was measured by flow cytometry in ITP patients, before and after IVIG therapy, as well as in control subjects. Peripheral blood monocytes were labelled with fluorescent-specific antibodies. There were no significant differences in the absolute number of [corrected] CD14(+) CD32B(+) monocytes, and [corrected] the percentages of CD14(+) CD32B(+) cells in mononuclear cells or monocytes. [corrected]. We suggest that IVIG does not increase FcγRIIB expression in peripheral blood monocytes in children with ITP.


Asunto(s)
Inmunoglobulinas Intravenosas/administración & dosificación , Monocitos/inmunología , Receptores de IgG/sangre , Trombocitopenia/inmunología , Enfermedad Aguda , Animales , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Citometría de Flujo , Proteínas Ligadas a GPI/sangre , Proteínas Ligadas a GPI/inmunología , Humanos , Lactante , Receptores de Lipopolisacáridos/sangre , Receptores de Lipopolisacáridos/inmunología , Macrófagos/inmunología , Masculino , Ratones , Recuento de Plaquetas , Receptores de IgG/biosíntesis , Receptores de IgG/inmunología
7.
RSC Adv ; 13(1): 665-673, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36605633

RESUMEN

A substantial reduction in the thermal conductivity for strontium titanate (ABO3) perovskite structure was realized for the A-site substitution of gadolinium (rare earth element) in SrTiO3 ceramics. The effect of Gd3+ substitution on the structure, composition, and thermoelectric properties of SrTiO3 was investigated. The substitution of Gd3+ in the SrTiO3 matrix resulted in the minimalization of thermal conductivity. The thermal conductivity followed a similar trend as that of thermal diffusivity, but specific heat capacity exhibited a non-monotonic trend. The thermal conductivity is reduced to 1.05 W m-1 K-1 for the minimal substitutional composition (Sr0.99Gd0.01TiO3) which is 30% less than that of SrTiO3 at 303 K. The variation in the ionic radii and atomic mass of the heavier rare earth Gd3+ substituted over Sr2+ resulted in the reduction of thermal conductivity of SGTO ceramics caused by the corresponding boundary scattering at low temperatures and temperature-independent phonon-impurity scattering at high temperatures.

8.
Chemosphere ; 288(Pt 1): 132236, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34649090

RESUMEN

Hierarchical orderd macroporous TiO2 architecture (HOMTA) was prepared with aid of ethylenediamine (EDA) and investigated the impact of amine molecules on the properties of TiO2 architecture. The different variation of amine molecules (EDA) leads to tunning the morphology under hydrothermal approach which is confirmed by FESEM and TEM analysis. The XRD and Raman studies confirms the crystal structure of anatase and brookite phase of TiO2. The surface of the architecture strongly depended on the concentration of EDA which plays a vital role in surface area which is revealed by Brunauer Emmett-Teller (BET) analysis. The obtained HOMTA was employed as photocatalyst and active photoanode in the dye sensitized solar cells (DSSC). The DSSC device exhibits excellent efficiency (η) of 5.27% for the EDA capped TiO2 (S5) which had high surface area (167.11 m2/g) for better dye loading, whereas the lower concentration of EDA capped TiO2 (S1, S2, S3 and S4) resulted the efficiency of 2.14, 3.90, 3.25 and 4.37%, respectively. The efficiency of photocatlysis degradation of the prepared samples (S1, S2, S3, S4 and S5) was 94.8, 90.47, 91.41, 91.32 and 93.75% under light source. The excellent photocatalysis property was achieved by S5 within 6 min due to high surface area which inducing more active site.


Asunto(s)
Restauración y Remediación Ambiental , Titanio , Colorantes , Luz Solar
9.
RSC Adv ; 11(31): 19059-19069, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35478652

RESUMEN

Hierarchical nanostructures and the effects of ligands on their structure formation were investigated. Morphological analysis showed the change in the morphology from nanospindles to hollow hexagonal nanodisks with the change in ligands. Structural analysis exhibited the formation of both hexagonal ZnO and monoclinic CuO structures in the composition. The elemental composition confirms the presence of CuO and ZnO in the composition. An ultra-fast degradation was achieved for the nanocomposites. The ZnO/CuO composite with ethylenediamine showed the best activity by degrading 98.77% of the methylene blue dye in 36 min. A possible photocatalytic mechanism is proposed.

10.
RSC Adv ; 11(31): 19283-19293, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35478632

RESUMEN

In the past few decades, air and water pollution by organic dyes has become a serious concern due to their high toxicity. Removal of these organic dyes from polluted water bodies is a serious environmental concern and the development of new advanced photocatalytic materials for decomposing organic dyes can be a good solution. In this work, layered molybdenum disulfide/nickel disulfide (MoS2/NiS2) nanocomposites with various NiS2 content was synthesized by a one-step hydrothermal method using citric acid as a reducing agent. The X-ray diffraction pattern shows the hexagonal and cubical crystal structure of MoS2 and NiS2, respectively. Morphological analysis confirms the formation of MoS2/NiS2 nanosheets. The elemental composition of the samples was carried out by XPS, which shows a significant interaction between NiS2 and MoS2. The photocatalytic performance of MoS2/NiS2 nanocomposites was studied by the degradation of rhodamine B (RhB). Ni-4 sample shows higher photocatalytic activity with a maximum degradation of 90.61% under visible light irradiation for 32 min.

11.
J Colloid Interface Sci ; 584: 295-309, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33069028

RESUMEN

The hybrid of organic conducting polymers and inorganic materials with ultralow thermal conductivity, which is a promising strategy for the realization of polymer based effective thermoelectric (TE) applications. In this work, ultrathin layered molybdenum disulphide (MoS2) nanosheets/PANI nanocomposites are prepared by hydrothermal route. The effect of varying PANI wt% in the nanocomposites and its interface effect on thermoelectric properties are well investigated. The successful incorporation of PANI between the MoS2 layers confirmed by high resolution transmission electron microscope (HRTEM). The significantly enhanced potential difference of MoS2/ PANI nanocomposites with increasing PANI content is well clarified by the increased Seebeck value. The variable range hopping property is identified and conductivity is raised up highly due to insertion of PANI in layered van der Waal's gap of MoS2. The effective interface facilitates charge for fast transport. The reduced thermal conductivity is observed of about 0.248 W*m-1*K-1 for 2.5 wt% addition of PANI. The key factor is that the stability of the sample is improved for MoS2/ PANI nanocomposites than pristine MoS2. Our work paved a new approach to improve TE performance by preparing TE MoS2 material through simple chemical route.

12.
Biomed Res Int ; 2021: 6666642, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33855077

RESUMEN

Nitrocellulose with silver nanoparticle (AgNP/NC) composite was prepared in situ using Ag(CH3CO2) and nitrocellulose without any reducing agent. The composite materials synthesized were spray coated onto glass substrates to obtain thin films. The AgNPs/NC composites were characterized by ultraviolet-visible, Fourier transform infrared, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The antimicrobial activity of AgNPs/NC composite was investigated by tube method and time-kill kinetic studies against three microbial species, including Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), and Candida albicans (ATCC 10231). The antibiofilm activities were qualitatively determined against all three organisms. Prepared AgNPs/NC films exhibited good antimicrobial activity and significant inhibition of biofilm development against all three microbial species. The effective dispersion of AgNPs/NC in biofilm was responsible for the significant antibiofilm activity of the prepared material. The reported AgNPs/NC composite can be used as coating additive in bacteriocidal paint which can be applied onto surfaces such as in healthcare environments.


Asunto(s)
Antiinfecciosos/farmacología , Biopelículas/efectos de los fármacos , Colodión/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Adhesión Bacteriana/efectos de los fármacos , Cinética , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Sustancias Reductoras , Espectrometría por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Resonancia por Plasmón de Superficie , Propiedades de Superficie , Temperatura , Termogravimetría , Factores de Tiempo
13.
RSC Adv ; 8(47): 26664-26675, 2018 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-35541077

RESUMEN

Edge-rich active sites of ultrathin layered molybdenum disulphide (MoS2) nanosheets were synthesized by a hydrothermal method. The effect of pH on the formation of MoS2 nanosheets and their photocatalytic response have been investigated. Structural and elemental analysis confirm the presence of S-Mo-S in the composition. Morphological analysis confirms the presence of ultrathin layered nanosheets with a sheet thickness of 10-28 nm at pH 1. The interplanar spacing of MoS2 layers is in good agreement with the X-ray diffraction and high-resolution transmission electron microscopy results. A comparative study of the photocatalytic performance for the degradation of methylene blue (MB) and rhodamine B (RhB) by ultrathin layered MoS2 under visible light irradiation was performed. The photocatalytic activity of the edge-rich ultrathin layered nanosheets showed a fast response time of 36 min with the degradation rate of 95.3% of MB and 41.1% of RhB. The photocatalytic degradation of MB was superior to that of RhB because of the excellent adsorption of MB than that of RhB. Photogenerated superoxide radicals were the key active species for the decomposition of organic compounds present in water, as evidenced by scavenger studies.

14.
Kyobu Geka ; 60(13): 1148-51, 2007 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-18078079

RESUMEN

We report a case of cardiac angiosarcoma of the right atrium. A 20-year-old woman was admitted to the Kyoto Prefectural University of Medicine with severe chest pain and dyspnea. A cardiac tumor was diagnosed by computed tomography (CT), echocardiography, and cinecardiography. The tumor marker CA125 was 293 U/ml (normal : <35 U/ml). Therefore a CT-guided transthoracic needle biopsy under CT fluoroscopic guidance for definitive diagnosis was performed after obtaining the patient's informed consent. Pathohistologically, the tumor was diagnosed as a cardiac angiosarcoma. The use of an intravenous infusion of contrast material contributed greatly to clear visualization of the tumor margin and cardiac lumen and assisted in easily and correctly advancing the needle toward the tumor. Moreover, tumor marker CA125 was a good indicator of therapeutic efficacy.


Asunto(s)
Neoplasias Cardíacas/diagnóstico , Hemangiosarcoma/diagnóstico , Adulto , Biopsia , Antígeno Ca-125/sangre , Femenino , Atrios Cardíacos , Humanos
15.
Kyobu Geka ; 59(6): 483-5, 2006 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-16780069

RESUMEN

Use of a central venous catheter (CVC) may be complicated by a catheter fracture, causing an embolism. Pinch-off syndrome is a recognized complication that develops from the use of implantable subclavian venous access devices. Although rare, as it occurs in only 0.8% of the reported cases, the condition can appear as a complication secondary to the insertion of a CVC. We experienced a case of CVC division in a 26-year-old male who had a CVC implanted through the subclavian vein. We failed in our attempt to remove the catheter fragment using video-assisted thoracoscopic surgery (VATS). If no complication occur over a long-term, it is highly possible that the catheter fragment will become adhered to the vessel wall. Therefore, it may not be necessary to remove the fragment in those cases.


Asunto(s)
Cateterismo Venoso Central/efectos adversos , Cirugía Torácica Asistida por Video , Adulto , Catéteres de Permanencia , Falla de Equipo , Humanos , Masculino
16.
Oncogenesis ; 5(8): e253, 2016 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-27526107

RESUMEN

KRAS mutations occur in 30-40% of all cases of human colorectal cancer (CRC). However, to date, specific therapeutic agents against KRAS-mutated CRC have not been developed. We previously described the generation of mouse models of colon cancer with and without Kras mutations (CDX2P-G22Cre;Apc(flox/flox); LSL-Kras(G12D) and CDX2P-G22Cre;Apc(flox/flox) mice, respectively). Here, the two mouse models were compared to identify candidate genes, which may represent novel therapeutic targets or predictive biomarkers. Differentially expressed genes in tumors from the two mouse models were identified using microarray analysis, and their expression was compared by quantitative reverse transcription-PCR (qRT-PCR) and immunohistochemical analyses in mouse tumors and surgical specimens of human CRC, with or without KRAS mutations, respectively. Furthermore, the functions of candidate genes were studied using human CRC cell lines. Microarray analysis of 34 000 transcripts resulted in the identification of 19 candidate genes. qRT-PCR analysis data showed that four of these candidate genes (Clps, Irx5, Bex1 and Rcan2) exhibited decreased expression in the Kras-mutated mouse model. The expression of the regulator of calcineurin 2 (RCAN2) was also observed to be lower in KRAS-mutated human CRC. Moreover, inhibitory function for cancer cell proliferation dependent on calcineurin was indicated with overexpression and short hairpin RNA knockdown of RCAN2 in human CRC cell lines. KRAS mutations in CRC lead to a decrease in RCAN2 expression, resulting in tumor proliferation due to derepression of calcineurin-nuclear factor of activated T cells (NFAT) signaling. Our findings suggest that calcineurin-NFAT signal may represent a novel molecular target for the treatment of KRAS-mutated CRC.

17.
Biochim Biophys Acta ; 1203(2): 298-303, 1993 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-8268214

RESUMEN

It was observed that the purified urinary bikunin (trypsin inhibitor) consisted of four major isomers with different electric charges which could be separated by HPLC using a Mono Q column. These isomers revealed the same antitrypsin activity and did not show any differences in the apparent molecular weight by SDS-PAGE, amino-acid composition, N-terminal amino-acid sequence (1-40) and C-terminal amino acid (Leu). The contents of sialic acid and uronic acid were also identical among these isomers. However, analysis of chondroitin sulfate revealed all the glycosaminoglycan chains of these isomers were undersulfated, comprising nonsulfated and 4-sulfated disaccharide units, and 4-sulfated disaccharide unit ratio varied among these isomers. After the chondroitin ABC lyase digestion, all the isomers were eluted at the same position on a Mono Q column chromatography. These results indicated that charge isomers of urinary bikunin was attributed to the difference on sulfation ratio in a glycosaminoglycan chain.


Asunto(s)
Glicoproteínas/química , Glicoproteínas de Membrana , Inhibidor de la Tripsina de Soja de Kunitz , Inhibidores de Tripsina/química , Aminoácidos/análisis , Cromatografía Líquida de Alta Presión , Electroquímica , Femenino , Glicoproteínas/orina , Humanos , Isomerismo , Masculino , Inhibidores de Tripsina/orina
18.
Br J Pharmacol ; 130(5): 981-6, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10882381

RESUMEN

1. The nitroguanidine insecticide imidacloprid along with a second generation of related compounds including nitenpyram, all nicotinic acetylcholine (ACh) receptor ligands, are used increasingly in many countries. Site-directed mutagenesis and heterologous expression in Xenopus laevis oocytes have been deployed to investigate mutants (G189D and G189E) of the chicken alpha7 homomer-forming nicotinic receptor subunit which are predicted to enhance the negative charge at the negative subsite (loop D) of the ACh binding site. 2. Xenopus oocytes expressing wild-type alpha7 nicotinic receptors respond to imidacloprid with rapid inward currents. Imidacloprid and nitenpyram are partial agonists, whereas ACh, (-)-nicotine and (+)-epibatidine are full agonists. 3. Compared to wild-type alpha7, the mutant G189D and G189E receptors are much less sensitive to the insecticides, whereas their sensitivity to (-)-nicotine, ACh and (+)-epibatidine is only slightly reduced. In contrast, G189N and G189Q mutants are sensitive not only to ACh, (-)-nicotine and (+)-epibatidine, but also to the two insecticides. Thus reduction of the insecticide-sensitivity by the mutations G189D and G189E are attributed to an increase in negativity of loop D. Desnitro-imidacloprid (DN-IMI), an imidacloprid derivative lacking the nitro group is a potent agonist on the G189D and G189E mutants suggesting an important role of loop D in nicotinic receptor interactions with the nitro group of nitroguanidine insecticides.


Asunto(s)
Imidazoles/farmacología , Insecticidas/farmacología , Receptores Nicotínicos/efectos de los fármacos , Animales , Pollos , Relación Dosis-Respuesta a Droga , Femenino , Mutagénesis Sitio-Dirigida , Neonicotinoides , Nitrocompuestos , Receptores Nicotínicos/química , Receptores Nicotínicos/fisiología , Proteínas Recombinantes/efectos de los fármacos , Xenopus laevis
19.
Psychopharmacology (Berl) ; 79(2-3): 266-70, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6133307

RESUMEN

The clinical application of a dopamine radioreceptor assay for neuroleptics has been proposed. Simultaneous monitoring of serum antidopaminergic (anti-DA), antiserotonergic (anti-5HT) antiadrenergic (anti-NA) activities may provide a better understanding of clinical effects of neuroleptics. Serum anti-DA and anti-5HT activities were estimated by competition for 3H-spiperone binding to dopamine and serotonin receptors in rat brain, respectively, and anti-NA activity by competition for 3H-WB-4101 binding to alpha-receptors. Thirty-one patients receiving maintenance doses of chlorpromazine (CPZ) chronically were studied. Serum activities varied among patients receiving the same dose, but correlated significantly with dose. Anti-DA activity also correlated with both anti-5HT anti-NA activities, and the average ratio of anti-5HT or anti-NA to anti-DA activity was slightly reduced by metabolism of CPZ. However, some patients had a different spectrum of serum activities from that of in vitro activities. Serum prolactin (PRL) correlated weakly with all the serum activities. The serum PRL anti-DA activity ratio appeared to be independent of anti-5HT or anti-NA activity, suggesting the predominant involvement of anti-DA activity in the stimulation of PRL release.


Asunto(s)
Antagonistas Adrenérgicos alfa , Clorpromazina/uso terapéutico , Prolactina/sangre , Receptores Dopaminérgicos/efectos de los fármacos , Receptores de Serotonina/efectos de los fármacos , Esquizofrenia/sangre , Adulto , Anciano , Clorpromazina/sangre , Enfermedad Crónica , Humanos , Masculino , Persona de Mediana Edad , Ensayo de Unión Radioligante , Esquizofrenia/tratamiento farmacológico
20.
Eur J Pharmacol ; 89(1-2): 27-33, 1983 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-6861888

RESUMEN

After acute administration of haloperidol, homovanillic acid (HVA) levels were increased in the prefrontal cortex, anterior cingulate cortex, discrete limbic areas and A14 dopamine (DA) neurons. The maximal effect of haloperidol was attained more slowly in the prefrontal cortex and amygdala than in the other regions. The ED50 of haloperidol was 0.03 mg/kg in the prefrontal cortex, but was 0.06-0.07 mg/kg in other areas examined. After repeated administration of haloperidol, tolerance to the HVA increase was observed in the striatum and all limbic areas examined, the amygdala being the most susceptible to this tolerance. In contrast, no tolerance was found in the anteromedial and suprarhinal DA neurons of the prefrontal cortex and A14 DA neurons. These results suggest that the prefrontal cortex may be a possible site for the antipsychotic action of haloperidol. On the other hand, no change of HVA levels in the A12 and A13 DA neurons of the hypothalamus was observed after haloperidol treatments, suggesting a lack of neuronal feedback mechanism in the A12 and A13 DA neurons.


Asunto(s)
Encéfalo/metabolismo , Dopamina/fisiología , Haloperidol/farmacología , Ácido Homovanílico/metabolismo , Fenilacetatos/metabolismo , Animales , Encéfalo/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas , Factores de Tiempo
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