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1.
Phys Rev Lett ; 132(8): 082501, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457706

RESUMO

The structure and decay of the most neutron-rich beryllium isotope, ^{16}Be, has been investigated following proton knockout from a high-energy ^{17}B beam. Two relatively narrow resonances were observed for the first time, with energies of 0.84(3) and 2.15(5) MeV above the two-neutron decay threshold and widths of 0.32(8) and 0.95(15) MeV, respectively. These were assigned to be the ground (J^{π}=0^{+}) and first excited (2^{+}) state, with E_{x}=1.31(6) MeV. The mass excess of ^{16}Be was thus deduced to be 56.93(13) MeV, some 0.5 MeV more bound than the only previous measurement. Both states were observed to decay by direct two-neutron emission. Calculations incorporating the evolution of the wave function during the decay as a genuine three-body process reproduced the principal characteristics of the neutron-neutron energy spectra for both levels, indicating that the ground state exhibits a strong spatially compact dineutron component, while the 2^{+} level presents a far more diffuse neutron-neutron distribution.

2.
Phys Rev Lett ; 126(8): 082501, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33709737

RESUMO

A kinematically complete quasifree (p,pn) experiment in inverse kinematics was performed to study the structure of the Borromean nucleus ^{17}B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for 1s_{1/2} and 0d_{5/2} orbitals, and a surprisingly small percentage of 9(2)% was determined for 1s_{1/2}. Our finding of such a small 1s_{1/2} component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in ^{17}B. The present work gives the smallest s- or p-orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of s or p orbitals is not a prerequisite for the occurrence of a neutron halo.

3.
Phys Rev Lett ; 125(25): 252501, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33416401

RESUMO

The formation of a dineutron in the ^{11}Li nucleus is found to be localized to the surface region. The experiment measured the intrinsic momentum of the struck neutron in ^{11}Li via the (p,pn) knockout reaction at 246 MeV/nucleon. The correlation angle between the two neutrons is, for the first time, measured as a function of the intrinsic neutron momentum. A comparison with reaction calculations reveals the localization of the dineutron at r∼3.6 fm. The results also support the density dependence of dineutron formation as deduced from Hartree-Fock-Bogoliubov calculations for nuclear matter.

4.
J Geophys Res Atmos ; 124(1): 387-413, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31007989

RESUMO

Global multiconstituent concentration and emission fields obtained from the assimilation of the satellite retrievals of ozone, CO, NO2, HNO3, and SO2 from the Ozone Monitoring Instrument (OMI), Global Ozone Monitoring Experiment 2, Measurements of Pollution in the Troposphere, Microwave Limb Sounder, and Atmospheric Infrared Sounder (AIRS)/OMI are used to understand the processes controlling air pollution during the Korea-United States Air Quality (KORUS-AQ) campaign. Estimated emissions in South Korea were 0.42 Tg N for NO x and 1.1 Tg CO for CO, which were 40% and 83% higher, respectively, than the a priori bottom-up inventories, and increased mean ozone concentration by up to 7.5 ± 1.6 ppbv. The observed boundary layer ozone exceeded 90 ppbv over Seoul under stagnant phases, whereas it was approximately 60 ppbv during dynamical conditions given equivalent emissions. Chemical reanalysis showed that mean ozone concentration was persistently higher over Seoul (75.10 ± 7.6 ppbv) than the broader KORUS-AQ domain (70.5 ± 9.2 ppbv) at 700 hPa. Large bias reductions (>75%) in the free tropospheric OH show that multiple-species assimilation is critical for balanced tropospheric chemistry analysis and emissions. The assimilation performance was dependent on the particular phase. While the evaluation of data assimilation fields shows an improved agreement with aircraft measurements in ozone (to less than 5 ppbv biases), CO, NO2, SO2, PAN, and OH profiles, lower tropospheric ozone analysis error was largest at stagnant conditions, whereas the model errors were mostly removed by data assimilation under dynamic weather conditions. Assimilation of new AIRS/OMI ozone profiles allowed for additional error reductions, especially under dynamic weather conditions. Our results show the important balance of dynamics and emissions both on pollution and the chemical assimilation system performance.

5.
Sci Total Environ ; 499: 154-65, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25181047

RESUMO

Aerosol samples were collected in autumn 2007 on day- and nighttime basis in the northern receptor site of Beijing, China. The samples were analyzed for total carbon (TC) and water-soluble dicarboxylic acids (C2-C12), oxocarboxylic acids (C2-C9), glyoxal and methylglyoxal to better understand the photochemical aging of organic aerosols in the vicinity of Beijing. Concentrations of TC are 50% greater in daytime when winds come from Beijing than in nighttime when winds come from the northern forest areas. Most diacids showed higher concentrations in daytime, suggesting that the organics emitted from the urban Beijing and delivered to the northern vicinity in daytime are subjected to photo-oxidation to result in diacids. However, oxalic acid (C2), which is the most abundant diacid followed by C3 or C4, became on average 30% more abundant in nighttime together with azelaic, ω-oxooctanoic and ω-oxononanoic acids, which are specific oxidation products of biogenic unsaturated fatty acids. Methylglyoxal, an oxidation product of isoprene and a precursor of oxalic acid, also became 29% more abundant in nighttime. Based on a positive correlation between C2 and glyoxylic acid (ωC2) in nighttime when relative humidity significantly enhanced, we propose a nighttime aqueous phase production of C2 via the oxidation of ωC2. We found an increase in the contribution of diacids to TC by 3 folds during consecutive clear days. This study demonstrates that diacids and related compounds are largely produced in the northern vicinity of Beijing via photochemical processing of organic precursors emitted from urban center and forest areas.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Ácidos Dicarboxílicos/análise , Monitoramento Ambiental , Processos Fotoquímicos , Aerossóis/química , Movimentos do Ar , Poluentes Atmosféricos/química , Atmosfera/química , China , Ácidos Dicarboxílicos/química
6.
Environ Sci Pollut Res Int ; 21(5): 3873-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24288059

RESUMO

Carbon monoxide (CO) is of great interest as a restriction factor for pollutants related to incomplete combustions. This study attempted to evaluate CO emission in East China using the analytical Bayesian inverse method and observations at Mount Hua in springtime. The mixing ratio of CO at the receptor was calculated using 5-day source-receptor relationship (SRR) simulated by a Lagrangian Particle Dispersion Model (FLEXPART) and CO emission flux. The stability of the inversion solution was evaluated on the basis of repeated random sampling simulations. The inversion results demonstrated that there were two city cluster regions (the Beijing-Tianjin-Hebei region and the low reaches of the Yangtze River Delta) where the difference between a priori (Intercontinental Chemical Transport Experiment-Phase B, INTEX-B) and a posteriori was statistically significant and the a priori might underestimate the CO emission flux by 37 %. A correction factor (a posteriori/a priori) of 1.26 was suggested for CO emission in China in spring. The spatial distribution and magnitude of the CO emission flux were comparable to the latest regional emission inventory in Asia (REAS2.0). Nevertheless, further evaluation is still necessary in view of the larger uncertainties for both the analytical inversion and the bottom-up statistical approaches.


Assuntos
Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Modelos Teóricos , Altitude , Teorema de Bayes , China , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Estações do Ano
7.
Acta Biol Hung ; 59 Suppl: 105-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18652381

RESUMO

The pond snail, Lymnaea stagnalis, can locomote on its back utilizing the surface tension of the water. We have called this form of movement 'back-swimming'. In order to perform this behavior, the snail must flip itself over on its back so that its foot is visible from above. Little is known about the mechanism of this back-swimming. As a first step for the elucidation of this mechanism, we measured the speed of back-swimming of Lymnaea at the different times of the day. They back-swam significantly faster in the morning than just before dark. These data are consistent with our earlier findings on circadian-timed activity pattern in Lymnaea. Lymnaea appear to secrete a thin membrane-like substance from their foot that may allow them to back-swim. To confirm the existence of this substance and to examine whether this substance is hydrophobic or hydrophilic, we applied a detergent onto the foot during back-swimming. A single drop of 1% Tween 20 drifted Lymnaea away that were still kept at the water surface. These results suggest that Lymnaea secrete a hydrophobic substance from their foot that floats to the water surface allowing Lymnaea to back-swim.


Assuntos
Lymnaea/fisiologia , Animais , Ritmo Circadiano/fisiologia , Detergentes , Interações Hidrofóbicas e Hidrofílicas , Tensão Superficial , Natação/fisiologia , Água
8.
Vet Res Commun ; 32(7): 563-73, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18575956

RESUMO

Intermediate insulin injections are commonly used for glycemic control in insulin dependent diabetic dogs acting as a replacement for natural insulin. Neutral Protamin Hagedorn (NPH) insulin and insulin glargine are two types of injectable insulin preparations commonly used in humans. In our study, we investigated the time-action profiles of both aforementioned insulin preparations in normal dogs in order to determine whether co-administration of NPH and glargine would be of benefit to insulin dependent diabetic dogs as it is for humans suffering from insulin dependent diabetes. Time-action profiles of NPH insulin and insulin glargine in normal dogs demonstrated a clear difference between both insulin preparations confirming that NPH insulin is an intermediate-acting preparation whereas insulin glargine is a long-lasting preparation. In addition, co-administration of NPH insulin and insulin glargine resulted in tight glycemic control as compared to NPH insulin alone in insulin dependent diabetic dogs. However, co-administration result in hypoglycemia at the dosages tested.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Doenças do Cão/tratamento farmacológico , Insulina Isófana/farmacologia , Insulina/análogos & derivados , Animais , Glicemia/efeitos dos fármacos , Cães , Feminino , Insulina/farmacologia , Insulina Glargina , Insulina de Ação Prolongada , Dose Letal Mediana , Masculino , Fatores de Tempo
9.
J Int Med Res ; 34(1): 109-14, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16604831

RESUMO

We report an extremely rare case of recurrent alpha-fetoprotein (AFP)-producing gastric cancer without re-elevation of serum AFP. The patient was a 78-year-old woman with AFP-producing gastric cancer, a rare type of gastric adenocarcinoma. A Borrmann III gastric tumour was surgically resected and AFP-producing gastric cancer was diagnosed based on high levels of serum AFP (705.44 ng/ml) and immunohistochemical examination of the tumour. The serum AFP level decreased to the normal range after resection without any sign of recurrence by imaging, but the patient developed local recurrence of the cancer and died 13 months after surgery. No re-elevation of serum AFP levels was observed after recurrence. Although serum AFP levels are believed to be useful for follow-up in the post-operative period, the possibility that serum AFP levels do not always correlate with the extent of the cancer should be kept in mind.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Gástricas/metabolismo , alfa-Fetoproteínas/análise , alfa-Fetoproteínas/biossíntese , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Colo Transverso , Evolução Fatal , Feminino , Seguimentos , Gastrectomia , Gastroscopia , Humanos , Imuno-Histoquímica , Excisão de Linfonodo , Metástase Linfática , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Fatores de Tempo , Tomografia Computadorizada por Raios X
10.
Clin Exp Immunol ; 144(1): 85-93, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16542369

RESUMO

Chromosome 22q11.2 deletion syndrome is a common disorder characterized by thymic hypoplasia, conotruncal cardiac defect and hypoparathyroidism. Patients have a risk of infections and autoimmunity associated with T lymphocytopenia. To assess the immunological constitution of patients, the numerical changes and cytokine profile of circulating T cells were analysed by flow cytometry and real-time polymerase chain reaction (PCR). CD3+, CD4+, T cell receptor (TCR)alphabeta+ or CD8alphaalpha+ cell counts were lower, and CD56+ cell counts were higher in patients than in controls during the period from birth to adulthood. The ageing decline of CD3+ or CD4+ cell counts was slower in patients than in controls. The proportion of CD8alphaalpha+ cells increased in controls, and the slope index was larger than in patients. On the other hand, both the number and proportion of Valpha24+ cells increased in patients, and the slope indexes tended to be larger than in controls. The positive correlation of the number of T cells with CD8alphaalpha+ cells was observed only in patients, and that with Valpha24+ cells was seen only in controls. No gene expression levels of interferon (IFN)-gamma, interleukin (IL)-10, transforming growth factor (TGF)-beta, cytotoxic T lymphocyte antigen 4 (CTLA4) or forkhead box p3 (Foxp3) in T cells differed between patients and controls. There was no significant association between the lymphocyte subsets or gene expression levels and clinical phenotype including the types of cardiac disease, hypocalcaemia and frequency of infection. These results indicated that T-lymphocytopenia in 22q11.2 deletion patients became less severe with age under the altered composition of minor subsets. The balanced cytokine profile in the limited T cell pool may represent a T cell homeostasis in thymic deficiency syndrome.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Citocinas/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Envelhecimento/genética , Envelhecimento/imunologia , Antígenos CD , Antígenos de Diferenciação/análise , Complexo CD3/imunologia , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos/imunologia , Antígeno CTLA-4 , Criança , Pré-Escolar , Cromossomos Humanos Par 22/imunologia , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/imunologia , Feminino , Fatores de Transcrição Forkhead/análise , Expressão Gênica/genética , Expressão Gênica/imunologia , Humanos , Lactente , Interferon gama/análise , Interleucina-10/análise , Contagem de Linfócitos , Masculino , RNA Mensageiro/análise , Receptores de Antígenos de Linfócitos T/imunologia , Fator de Crescimento Transformador beta/análise
11.
Int J Pharm ; 203(1-2): 203-10, 2000 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-10967442

RESUMO

The purpose of the present study was to clarify the mechanism for l-menthol whisker growth. l-Menthol was mixed with an excipient, and the interaction was examined by IR measurement, thermal analysis and powder X-ray diffraction. Then we examined the involvement of the capillary condensation using the pore size distribution measurement. By mixing l-menthol with an excipient with whisker growth, the hydroxyl group stretching band of l-menthol was shifted to the higher wavenumber in the IR spectrum, the melting point and heat of fusion of l-menthol became lower in the thermal analysis, and the diffraction intensity of l-menthol became lower in the powder X-ray diffraction. The excipients with whisker growth showed the tendency to have the meso-pore involved in the capillary condensation in the pore size distribution measurement. From the above results, the whisker growth mechanism is considered as follows. When l-menthol was mixed with an excipient with whisker growth, the crystallinity of l-menthol was lowered and the vapor pressure was increased by the interaction mainly consisting of the hydrogen bond. The generated l-menthol vapor entered meso-pore, the saturated vapor pressure was lowered by the capillary condensation, and the nucleation occurred. The vapor was further supplied, generating the growth of whisker.


Assuntos
Excipientes/administração & dosagem , Mentol/administração & dosagem , Cristalização , Temperatura Alta , Mentol/química , Espectrofotometria Infravermelho
12.
Int J Pharm ; 199(1): 77-83, 2000 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-10794929

RESUMO

We investigated the application of Carbopol(R) (CP) as a novel coating material prepared with various grades of CP having different degrees of cross-linking and molecular weights. Viscosity and spray mist size of CP aqueous solutions at various concentrations of CP were measured. Core tablets containing theophylline (TP), as a model drug, were coated with CP at various coating ratios. The TP release profile from the CP-coated tablets was studied by the JP13 paddle method. CP tablets were prepared by compressing CP powder, and the swelling behavior of the CP tablets in JP 1st fluid, purified water, and JP 2nd fluid was observed. The spray mist size of all CP aqueous solutions was small at a concentration of 1% and below, and drastically increased over a concentration of 1%. This result suggests that the appropriate concentration of the CP solution for coating is 1% or below. Sustained release of TP from the CP-coated tablets at a coating ratio of only 3% was observed in the JP 1st fluid and purified water, although fast release was observed in the JP 2nd fluid. The fast release in the latter fluid may be due to the fact that CP is an acid material. These results suggest that it is feasible to control the drug release by use of an extremely small amount of CP coating and that CP is useful as a novel coating material.


Assuntos
Polivinil/química , Resinas Acrílicas , Broncodilatadores/química , Reagentes de Ligações Cruzadas , Portadores de Fármacos , Tamanho da Partícula , Solubilidade , Comprimidos com Revestimento Entérico , Teofilina/química , Viscosidade
13.
Bone Marrow Transplant ; 25(2): 209-12, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10673683

RESUMO

A 7-year-old boy with Diamond-Blackfan anemia (DBA) developed lymphoproliferative disease (LPD) after a cord blood transplant (CBT). 3.1 x 107/kg mononuclear cells from an HLA one-locus mismatched CB were transplanted after conditioning with total body irradiation (8 Gy), cyclophosphamide (200 mg/kg) and antithymocyte globulin (10 mg/kg). Complete engraftment occurred on day 33 post transplant. Despite the resolution of grade II graft-versus-host disease (GVHD), he died of lymphoma on day 130 post transplant. The tumor was of donor origin, indicating clonal proliferation of Epstein-Barr virus (EBV)-infected B cells. This is the first report of EBV-LPD after CBT. Post-transplant LPD can be a serious EBV-associated complication of CB grafts. Bone Marrow Transplantation (2000) 25, 209-212.


Assuntos
Infecções por Vírus Epstein-Barr/transmissão , Anemia de Fanconi/terapia , Sangue Fetal , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Linfoma de Células B/etiologia , Transfusão de Componentes Sanguíneos/efeitos adversos , Criança , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/etiologia , Infecções por Vírus Epstein-Barr/virologia , Anemia de Fanconi/sangue , Anemia de Fanconi/complicações , Anemia de Fanconi/virologia , Evolução Fatal , Feminino , Sangue Fetal/citologia , Sangue Fetal/imunologia , Sangue Fetal/virologia , Transplante de Tecido Fetal/efeitos adversos , Transplante de Tecido Fetal/imunologia , Sobrevivência de Enxerto , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/imunologia , Herpesvirus Humano 4/fisiologia , Teste de Histocompatibilidade , Humanos , Linfoma de Células B/sangue , Linfoma de Células B/virologia , Masculino , Condicionamento Pré-Transplante/efeitos adversos
14.
Gan To Kagaku Ryoho ; 27(14): 2235-8, 2000 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-11142168

RESUMO

A 52-year-old woman complaining of breast tumor was diagnosed as having advanced breast cancer (T4bN1M1-Stage IV), with metastasis of multiple organs (lung, liver, mediastinal and unilateral axillary lymph nodes) after which she underwent tumorectomy. Postoperative adjuvant therapy was performed using combined chemoendocrine therapy (CAF + 5'-DFUR + MPA). Following the endocrine therapy, the metastatic lesions of the liver and lung had disappeared. The adverse effects were not remarkable. Complete remission was continued for 2 years and 3 months, and the patient enjoyed a favorable quality of life.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Terapia Combinada , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Floxuridina/administração & dosagem , Fluoruracila/administração & dosagem , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Metástase Linfática , Mastectomia , Acetato de Medroxiprogesterona/administração & dosagem , Pessoa de Meia-Idade , Indução de Remissão
15.
J Control Release ; 63(3): 287-95, 2000 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-10601724

RESUMO

Solid dispersion composed of the poly(ethylene oxide) (PEO)-Carbopol((R)) (CP) interpolymer complex containing phenacetin (PHE) was prepared by using six grades of CP having various cross-linking degrees. We attempted to control the medicine release from the PEO-CP solid dispersion by varying the CP grade. The powder X-ray diffraction pattern and differential scanning calorimetry curves suggested that PHE existed in the amorphous state, and PEO in the crystalline state disappeared in the solid dispersions. The release profile of PHE varied depending on the CP grade. A small release rate was observed at CP910 and CP971P that are cross-linked at low and middle degrees, respectively. The Fourier transform-infrared (FT-IR) spectra showed that the amount of the PEO-CP complex formed by hydrogen bonding changed depending on the CP grade. With the cross-linked CP, a good correlation was observed between the hydrogen bonding percent and the percent released of the PHE after 60 min (D(60 min)), indicating that PHE release was controlled by the amount of PEO-CP complex formation in the solid dispersion. These results show that it is feasible to control the medicine release from PEO-CP solid dispersion by varying the CP grade.


Assuntos
Polietilenoglicóis/administração & dosagem , Polivinil/administração & dosagem , Resinas Acrílicas , Portadores de Fármacos , Fenacetina/administração & dosagem , Fenacetina/química , Polietilenoglicóis/química , Polivinil/química , Solubilidade
16.
Pharm Res ; 16(10): 1616-20, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10554106

RESUMO

PURPOSE: Fourteen kinds of salts consisting of various cations and anions in the Hofmeister series were used as additives for suppression of particle agglomeration in the fluidized bed coating. We attempted to clarify the relationship between the suppression effect of the salts and the Hofmeister series of their consistent ions. METHODS: Fluidized bed coating was carried out with hydroxypropylmethyl cellulose (HPMC) aqueous coating solution containing the salts and Celphere as core particles. To elucidate the salting-out power of the salts for HPMC, the transmittance of the coating solutions at 600 nm was measured at various temperatures and the phase separation temperature (T(PS)) was determined from the values at 50% transmittance. RESULTS: A high suppression effect was observed when the salts including high order ions in the Hofmeister series were added to the coating solution. T(PS) decreased in the presence of the salts except for sodium iodide and sodium thiocyanate and lowered with the higher order ion in the Hofmeister series. The particle agglomeration was suppressed with decrease in T(PS) of the HPMC aqueous coating solution. CONCLUSIONS: It has been suggested that the suppression effect of a salt on the particle agglomeration depended on the salting-out power of the salt. We regard sodium citrate and potassium citrate as very useful pharmaceutical additives for the suppression of particle agglomeration in actual pharmaceutical coating.


Assuntos
Pós , Tecnologia Farmacêutica , Algoritmos , Composição de Medicamentos , Excipientes , Derivados da Hipromelose , Metilcelulose/análogos & derivados , Tamanho da Partícula , Sais , Temperatura
17.
J Biol Chem ; 274(48): 33859-62, 1999 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-10567344

RESUMO

Mouse cyclin-dependent kinase (Cdk) 5 and yeast Pho85 kinase share similarities in structure as well as in the regulation of their activity. We found that mouse Cdk5 kinase produced in pho85Delta mutant cells could suppress some of pho85Delta mutant phenotypes including failure to grow on nonfermentable carbon sources, morphological defects, and growth defect caused by Pho4 or Clb2 overproduction. We also demonstrated that Cdk5 coimmunoprecipitated with Pho85-cyclins including Pcl1, Pcl2, Pcl6, Pcl9, and Pho80, and that the immunocomplex could phosphorylate Pho4, a native substrate of Pho85 kinase. Thus mouse Cdk5 is a functional homologue of yeast Pho85 kinase.


Assuntos
Quinases Ciclina-Dependentes/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimologia , Animais , Quinase 5 Dependente de Ciclina , Quinases Ciclina-Dependentes/genética , Ciclinas/genética , Ciclinas/metabolismo , Deleção de Genes , Teste de Complementação Genética , Camundongos , Mutação , Fenótipo , Fosforilação , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/genética
18.
Int J Pharm ; 187(1): 125-35, 1999 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-10502619

RESUMO

The powder (TN-PO) which adsorbed D,L-tocopheryl nicotinate (TN) as an oily medicine was prepared using porous calcium silicate (Florite(R)RE, FLR) as an adsorbing carrier. Tablets (TN-TAB) were produced by compression of TN-PO at different compression pressures. As TN-PO was compressed at the higher TN content in TN-PO and compression pressure, the more TN was exuded from TN-PO, and an increase in the degree of tablet coloration was observed. Therefore, FLR or colloidal silica (AEROSIL(R)200, AER) was newly added to TN-PO at compression to reduce the degree of tablet coloration. Further, the effects of addition of FLR or AER on the crushing strength, friability, porosity and disintegration property of the tablet and the dissolution property of TN from the tablet were studied. After addition of FLR or AER, a similar reduction of tablet coloration was observed. When the addition percentage of FLR to TN-PO exceeded 30%, the crushing strength of the tablet increased significantly. On the other hand, when TN-PO added with AER was compressed, no change was observed in the crushing strength of the tablet. The disintegration time of the tablet with added FLR was shorter than that of the tablet with added AER. At every addition percentage studied, the tablet with added FLR showed a higher releasing ability of TN compared with the tablet with added AER. These results indicate that it is possible to reduce tablet coloration by adding FLR or AER at compression of TN-PO. Further, it is considered that the differences in the crushing strength, disintegration property and dissolution property of TN between the tablets with added FLR or AER resulted in different liquid adsorbing and holding mechanisms of FLR particles and AER particles.


Assuntos
Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Compostos de Cálcio/administração & dosagem , Compostos de Cálcio/química , Química Farmacêutica/métodos , Ácidos Nicotínicos/administração & dosagem , Ácidos Nicotínicos/química , Silicatos/administração & dosagem , Silicatos/química , Dióxido de Silício/administração & dosagem , Dióxido de Silício/química , Vitamina E/análogos & derivados , Cor , Força Compressiva , Portadores de Fármacos , Porosidade , Pós , Comprimidos , Resistência à Tração , Vitamina E/administração & dosagem , Vitamina E/química
19.
Heart ; 81(5): 512-7, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10212170

RESUMO

OBJECTIVE: To determine whether the reactive hyperaemic response of the lower limb increases with improved exercise capacity after acute supplementation with L-arginine, the precursor of nitric oxide, in patients with chronic heart failure. METHODS: 19 patients with chronic heart failure were enrolled in the study. Rest calf blood flow and femoral occlusion induced calf blood flow changes were measured by venous occlusion plethysmography before and after intravenous infusion of 10% L-arginine solution (5 ml/kg for 30 minutes) or placebo. Postexercise calf blood flow was also measured after the experimental infusion. During both postinfusion periods, several exercise capacity indices were determined by a symptom limited cardiopulmonary exercise test using a bicycle ergometer. RESULTS: Baseline calf blood flow, systemic blood pressure, and heart rate showed no significant changes in either of the two experimental conditions. However, the occlusion induced blood flow response was significantly enhanced by L-arginine infusion (mean (SEM) peak flow, 19.6 (1.5) v 28.9 (3.1) ml/min/dl calf tissue; p < 0.01), but not by placebo (peak flow, 19.1 (1.4) v 20.9 (1.8) ml/min/dl calf tissue; NS). Calf blood flow response after exercise was also higher after L-arginine infusion than after placebo (peak flow, 4.8 (0.4) v 6.0 (0.8) ml/min/dl calf tissue; p < 0.05). L-arginine infusion had no significant effect compared with placebo on exercise capacity indices such as peak oxygen uptake (17.1 (1.0) v 15.8 (1.1) ml/min/kg; NS), anaerobic threshold (10.5 (0.6) v 10.4 (0.7) ml/min/kg; NS), and exercise time (296 (23) v 283 (22) s; NS). CONCLUSIONS: Acute supplementation with the nitric oxide precursor L-arginine increased lower limb reactive hyperaemia but did not lead to any significant improvement in exercise capacity in patients with chronic heart failure.


Assuntos
Arginina/uso terapêutico , Tolerância ao Exercício/efeitos dos fármacos , Insuficiência Cardíaca/tratamento farmacológico , Perna (Membro)/irrigação sanguínea , Vasodilatação/efeitos dos fármacos , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Cross-Over , Feminino , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Pletismografia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Método Simples-Cego
20.
Int J Pharm ; 178(1): 1-10, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10205620

RESUMO

It has been reported that the degree of particle agglomeration in fluidized bed coating is greatly affected by the spray mist size of coating solution. However, the mist size has generally been measured in open air, and few reports have described the measurement of the mist size in a chamber of the fluidized bed, in which actual coating is carried out. Therefore, using hydroxypropylmethyl cellulose (HPMC) aqueous solution as a coating solution, the spray mist size of the coating solution in a chamber of the fluidized bed was measured under various coating conditions, such as the distance from the spray nozzle, fluidization air volume, inlet air temperature and addition of sodium chloride (NaCl) into the coating solution. The mist size in the fluidized bed was compared with that in open air at various distances from the spray nozzle. Further, the relationship between the spray mist size and the degree of suppression of agglomeration at various NaCl concentrations during fluidized bed coating was studied. The mist size distribution showed a logarithmic normal distribution in both cases of the fluidized bed and open air. The number-basis median diameter of spray mist (D50) in the fluidized bed was smaller compared with that in open air. D50 increased with the increasing distance from the spray nozzle in both cases. In the fluidized bed, D50 decreased with the increasing fluidization air volume and inlet air temperature. The effect of NaCl concentration on the mist size was hardly observed, but the degree of suppression of agglomeration during coating increased with the increasing NaCl concentration in the coating solution.


Assuntos
Química Farmacêutica/métodos , Lactose/análogos & derivados , Metilcelulose/análogos & derivados , Tamanho da Partícula , Cloreto de Sódio/química , Temperatura , Química Farmacêutica/instrumentação , Lactose/química , Metilcelulose/química , Oxazinas
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