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1.
Phys Rev Lett ; 130(23): 232301, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37354417

RESUMO

For the first time, the (d,^{2}He) reaction was successfully used in inverse kinematics to extract the Gamow-Teller transition strength in the ß^{+} direction from an unstable nucleus. The new technique was made possible by the use of an active-target time-projection chamber and a magnetic spectrometer, and opens a path to addressing a range of scientific challenges, including in astrophysics and neutrino physics. In this Letter, the nucleus studied was ^{14}O, and the Gamow-Teller transition strength to ^{14}N was extracted up to an excitation energy of 22 MeV. The data were compared to shell-model and state-of-the-art coupled-cluster calculations. Shell-model calculations reproduce the measured Gamow-Teller strength distribution up to about 15 MeV reasonably well, after the application of a phenomenological quenching factor. In a significant step forward to better understand this quenching, the coupled-cluster calculation reproduces the full strength distribution well without such quenching, owing to the large model space, the inclusion of strong correlations, and the coupling of the weak interaction to two nucleons through two-body currents.


Assuntos
Núcleo Celular , Física , Fenômenos Biomecânicos
2.
Phys Rev Lett ; 126(15): 152701, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929230

RESUMO

The discrepancy between observations from γ-ray astronomy of the ^{60}Fe/^{26}Al γ-ray flux ratio and recent calculations is an unresolved puzzle in nuclear astrophysics. The stellar ß-decay rate of ^{59}Fe is one of the major nuclear uncertainties impeding us from a precise prediction. The important Gamow-Teller strengths from the low-lying states in ^{59}Fe to the ^{59}Co ground state are measured for the first time using the exclusive measurement of the ^{59}Co(t,^{3}He+γ)^{59}Fe charge-exchange reaction. The new stellar decay rate of ^{59}Fe is a factor of 3.5±1.1 larger than the currently adopted rate at T=1.2 GK. Stellar evolution calculations show that the ^{60}Fe production yield of an 18 solar mass star is decreased significantly by 40% when using the new rate. Our result eliminates one of the major nuclear uncertainties in the predicted yield of ^{60}Fe and alleviates the existing discrepancy of the ^{60}Fe/^{26}Al ratio.

3.
Phys Rev Lett ; 120(17): 172501, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29756826

RESUMO

The (^{12}N, ^{12}C) charge-exchange reaction at 175 MeV/u was developed as a novel probe for studying the isovector spin giant monopole resonance (IVSMR), whose properties are important for better understanding the bulk properties of nuclei and asymmetric nuclear matter. This probe, now available through the production of ^{12}N as a secondary rare-isotope beam, is exothermic, is strongly absorbed at the surface of the target nucleus, and provides selectivity for spin-transfer excitations. All three properties enhance the excitation of the IVSMR compared to other, primarily light-ion, probes, which have been used to study the IVSMR thus far. The ^{90}Zr(^{12}N,^{12}C) reaction was measured and the excitation energy spectra up to about 70 MeV for both the spin-transfer and non-spin-transfer channels were deduced separately by tagging the decay by γ emission from the ^{12}C ejectile. Besides the well-known Gamow-Teller and isobaric analog transitions, a clear signature of the IVSMR was identified. By comparing with the results from light-ion reactions on the same target nucleus and theoretical predictions, the suitability of this new probe for studying the IVSMR was confirmed.

4.
Phys Rev Lett ; 120(15): 152505, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756883

RESUMO

We observed the atomic 1s and 2p states of π^{-} bound to ^{121}Sn nuclei as distinct peak structures in the missing mass spectra of the ^{122}Sn(d,^{3}He) nuclear reaction. A very intense deuteron beam and a spectrometer with a large angular acceptance let us achieve a potential of discovery, which includes the capability of determining the angle-dependent cross sections with high statistics. The 2p state in a Sn nucleus was observed for the first time. The binding energies and widths of the pionic states are determined and found to be consistent with previous experimental results of other Sn isotopes. The spectrum is measured at finite reaction angles for the first time. The formation cross sections at the reaction angles between 0° and 2° are determined. The observed reaction-angle dependence of each state is reproduced by theoretical calculations. However, the quantitative comparison with our high-precision data reveals a significant discrepancy between the measured and calculated formation cross sections of the pionic 1s state.

5.
Phys Rev Lett ; 118(17): 172501, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28498679

RESUMO

The (^{10}Be,^{10}B^{*}[1.74 MeV]) charge-exchange reaction at 100 AMeV is presented as a new probe for isolating the isovector (ΔT=1) nonspin-transfer (ΔS=0) response of nuclei, with ^{28}Si being the first nucleus studied. By using a secondary ^{10}Be beam produced by fast fragmentation of ^{18}O nuclei at the NSCL Coupled Cyclotron Facility, applying the dispersion-matching technique with the S800 magnetic spectrometer to determine the excitation energy in ^{28}Al, and performing high-resolution γ-ray tracking with the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) to identify the 1022-keV γ ray associated with the decay from the 1.74-MeV T=1 isobaric analog state in ^{10}B, a ΔS=0 excitation-energy spectrum in ^{28}Al was extracted. Monopole and dipole contributions were determined through a multipole-decomposition analysis, and the isovector giant dipole resonance and isovector giant monopole resonance (IVGMR) were identified. The results show that this probe is a powerful tool for studying the elusive IVGMR, which is of interest for performing stringent tests of modern density functional theories at high excitation energies and for constraining the bulk properties of nuclei and nuclear matter. The extracted distributions were compared with theoretical calculations based on the normal-modes formalism and the proton-neutron relativistic time-blocking approximation. Calculated cross sections based on these strengths underestimate the data by about a factor of 2, which likely indicates deficiencies in the reaction calculations based on the distorted wave Born approximation.

6.
Ann Oncol ; 27(11): 2117-2123, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27502728

RESUMO

BACKGROUND: T-cell infiltration in tumors has been used as a prognostic tool in non-small-cell lung cancer (NSCLC). However, the influence of smoking habit and histological type on tumor-infiltrating lymphocytes (TILs) in NSCLC remains unclear. PATIENTS AND METHODS: We evaluated the prognostic significance of TILs (CD4+, CD8+, CD20+, and FOXP3+) according to histological type and smoking habit using automatic immunohistochemical staining and cell counting in 218 patients with NSCLC. RESULTS: In multivariate survival analyses of clinical, pathological, and immunological factors, a high ratio of FOXP3+ to CD4+ T cells (FOXP3/CD4) [hazard ratio (HR): 4.46, P < 0.01 for overall survival (OS); HR: 1.96, P < 0.05 for recurrence-free survival (RFS)] and a low accumulation of CD20+ B cells (HR: 2.45, P = 0.09 for OS; HR: 2.86, P < 0.01 for RFS) were identified as worse prognostic factors in patients with adenocarcinoma (AD). In non-AD, a low number of CD8+ T cells were correlated with an unfavorable outcome (HR: 7.69, P < 0.01 for OS; HR: 3.57, P < 0.02 for RFS). Regarding smoking habit in AD, a high FOXP3/CD4 ratio was poorly prognostic with a smoking history (HR: 5.21, P < 0.01 for OS; HR: 2.38, P < 0.03 for RFS), whereas a low accumulation of CD20+ B cells (HR: 4.54, P = 0.03 for OS; HR: 2.94, P < 0.01 for RFS) was confirmed as an unfavorable factor in non-smokers with AD. CONCLUSIONS: A low number of CD8+ T cells in non-AD, a high FOXP3/CD4 ratio in smokers with AD, and a low number of CD20+ B cells in non-smokers with AD were identified as independent unfavorable prognostic factors in resected NSCLC. Evaluating the influence of histological type and smoking habit on the immunological environment may lead to the establishment of immunological diagnosis and appropriate individualized immunotherapy for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Linfócitos do Interstício Tumoral/patologia , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD20/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Carcinoma Pulmonar de Células não Pequenas/classificação , Carcinoma Pulmonar de Células não Pequenas/imunologia , Intervalo Livre de Doença , Feminino , Fatores de Transcrição Forkhead/imunologia , Humanos , Estimativa de Kaplan-Meier , Linfócitos do Interstício Tumoral/imunologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fumar/efeitos adversos
7.
Phys Rev Lett ; 116(5): 052501, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26894705

RESUMO

A candidate resonant tetraneutron state is found in the missing-mass spectrum obtained in the double-charge-exchange reaction ^{4}He(^{8}He,^{8}Be) at 186 MeV/u. The energy of the state is 0.83±0.65(stat)±1.25(syst) MeV above the threshold of four-neutron decay with a significance level of 4.9σ. Utilizing the large positive Q value of the (^{8}He,^{8}Be) reaction, an almost recoilless condition of the four-neutron system was achieved so as to obtain a weakly interacting four-neutron system efficiently.

8.
Phys Rev Lett ; 113(3): 032502, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25083636

RESUMO

An approach is presented to experimentally constrain previously unreachable (p, γ) reaction rates on nuclei far from stability in the astrophysical rp process. Energies of all critical resonances in the (57)Cu(p,γ)(58)Zn reaction are deduced by populating states in (58)Zn with a (d, n) reaction in inverse kinematics at 75 MeV/u, and detecting γ-ray-recoil coincidences with the state-of-the-art γ-ray tracking array GRETINA and the S800 spectrograph at the National Superconducting Cyclotron Laboratory. The results reduce the uncertainty in the (57)Cu(p,γ) reaction rate by several orders of magnitude. The effective lifetime of (56)Ni, an important waiting point in the rp process in x-ray bursts, can now be determined entirely from experimentally constrained reaction rates.

9.
Phys Rev Lett ; 112(25): 252501, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-25014806

RESUMO

The Gamow-Teller strength in the ß(+) direction to (46)Sc was extracted via the (46)Ti(t,(3)He + γ) reaction at 115 MeV/u. The γ-ray coincidences served to precisely measure the very weak Gamow-Teller transition to a final state at 991 keV. Although this transition is weak, it is crucial for accurately estimating electron-capture rates in astrophysical scenarios with relatively low stellar densities and temperatures, such as presupernova stellar evolution. Shell-model calculations with different effective interactions in the pf shell-model space do not reproduce the experimental Gamow-Teller strengths, which is likely due to sd-shell admixtures. Calculations in the quasiparticle random phase approximation that are often used in astrophysical simulations also fail to reproduce the experimental Gamow-Teller strength distribution, leading to strongly overestimated electron-capture rates. Because reliable theoretical predictions of Gamow-Teller strengths are important for providing astrophysical electron-capture reaction rates for a broad set of nuclei in the lower pf shell, we conclude that further theoretical improvements are required to match astrophysical needs.

10.
Phys Rev Lett ; 108(26): 262503, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23004971

RESUMO

The double-differential cross sections for the (208)Pb and (90)Zr(t,(3)He) reactions at 300 MeV/u have been measured at the RI Beam Factory at RIKEN. This was the first physics experiment with the SHARAQ magnetic spectrometer. The combined analysis of the present (t,(3)He) data and previous (n,p) data provides the clearest identification for the ß(+) isovector spin monopole resonance both in the (208)Tl and (90)Y nuclei, and puts the observations of this giant resonance on a firm foundation. The measured distributions of the (t,(3)He) monopole cross sections were well reproduced by the distorted-wave Born approximation calculation, where the target transition density was calculated with the self-consistent Hartree-Fock plus random-phase approximation using the T43 Skyrme interaction. A major part of the expected ß(+) isovector spin monopole strength was found in the measured cross section spectra.

11.
Phys Rev Lett ; 104(21): 212504, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20867091

RESUMO

We report on the first successful extraction of a ß+ Gamow-Teller strength distribution from a radioactive isotope in an intermediate-energy charge-exchange experiment in inverse kinematics. The (7Li,7Be+γ(429 keV)) reaction at 100A MeV was used to measure Gamow-Teller transition strengths from 34P to states in 34Si. The results show that little mixing occurs between sd and pf shell configurations for the low-lying 0+ and 2+ states even though 34Si neighbors the island of inversion and low-lying 2ℏω intruder states exist. Shell-model calculations in the sdpf model space are consistent with these findings.

12.
Phys Rev Lett ; 103(1): 012503, 2009 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-19659141

RESUMO

The double-differential cross sections for the 48Ca(p,n) and 48Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) components. The integrated GT strengths up to an excitation energy of 30 MeV in 48Sc are 15.3+/-2.2 and 2.8+/-0.3 in the (p,n) and (n,p) spectra, respectively. In the (n,p) spectra additional GT strengths were found above 8 MeV where shell models within the fp shell-model space predict almost no GT strengths, suggesting that the present shell-model description of the nuclear matrix element of the two-neutrino double-beta decay is incomplete.

13.
Kyobu Geka ; 62(5): 388-90, 2009 May.
Artigo em Japonês | MEDLINE | ID: mdl-19425380

RESUMO

A 59-year-old man was admitted to the hospital, suspected of the rupture of descending thoracic aortic aneurysm due to sudden back pain. Enhanced computed tomography revealed a ruptured descending thoracic aortic aneurysm with huge hematoma and abdominal aortic aneurysm. Based on the above diagnosis, we performed urgent operation through left thoracotomy under unilateral lung ventilation. While dissecting the aneurysm, sudden hemodynamics deterioration occurred. Although cardiopulmonary bypass was introduced immediately through femoral artery and femoral vein cannulations, hemodynamics was not improved and unilateral lung ventilation got more unmanageable. We diagnosed right tension hemothorax due to the extension of aneurysm rupture into the right thoracic cavity. After placing a cannula at the distal arch for a central perfusion, we clamped the descending thoracic aorta at both the proximal and distal sites of the aneurysm. Thereafter we opened the aneurysm and drained the right thorax through the aneursym's tear. The aneurysm was replaced with a prosthetic woven-Dacron vascular graft. The patient's postoperative condition had been stable with no significant unfavorable event. The abdominal aortic aneurysm was replaced with a bifurcated graft on 51st postoperative day. He was discharged in good condition on the 69th postoperative day.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Ruptura Aórtica/cirurgia , Hemotórax/etiologia , Complicações Intraoperatórias , Humanos , Masculino , Pessoa de Meia-Idade
14.
Kyobu Geka ; 61(12): 1067-9, 2008 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-19048910

RESUMO

A 40-year-old woman was admitted to our hospital because of operation for giant intra-pervic tumor. She had a history of deep vein thrombosis. Suddenly she complained severe dyspnea while having a bath, and subsequently cardiogenic shock occurred. Immediately we set up percutaneous cardiopulmonary support (PCPS) for acute pulmonary thromboembolism. Despite thrombolytic therapy including the administration of urokinase and rt-PA, hemodinamics were not improved. Emergent pulmonary embolectomy was performed on-pump beating. Postoperative course was uneventful. The intra-pervic tumor was removed on the 24th postoperative day. She was discharged in good condition on the 38th postoperative day. Quick diagnosis and appropriate therapy are essential in patient with acute massive pulmonary thromboembolism.


Assuntos
Neoplasias Ovarianas/complicações , Embolia Pulmonar/etiologia , Embolia Pulmonar/cirurgia , Doença Aguda , Adulto , Feminino , Humanos
15.
Acta Myol ; 27: 19-24, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19108573

RESUMO

Caveolins, components of the uncoated invaginations of plasma membrane, regulate signal transduction and vesicular trafflicking. Loss of caveolin-3, resulting from dominant negative mutations of caveolin-3 causes autosomal dominant limb-girdle muscular dystrophy (LGMD) 1C and autosomal dominant rippling muscle disease (AD-RMD). Myostatin, a member of the muscle-specific transforming growth factor (TGF)-beta superfamily, negatively regulates skeletal muscle volume. Herein we review caveolin-3 suppressing of activation of type I myostatin receptor, thereby inhibiting subsequent intracellular signaling. In addition, a mouse model of LGMD1C has shown atrophic myopathy with enhanced myostatin signaling. Myostatin inhibition ameliorates muscular phenotype in the model mouse, accompanied by normalized myostatin signaling. Enhanced myostatin signaling by caveolin-3 mutation in human may contribute to the pathogenesis of LGMD1C. Therefore, myostatin inhibition therapy may be a promising treatment for patients with LGMD1C. More recent studies concerning regulation of TGF-beta superfamily signaling by caveolins have provided new insights into the pathogenesis of several human diseases.


Assuntos
Caveolina 3/fisiologia , Miostatina/fisiologia , Transdução de Sinais/fisiologia , Animais , Caveolina 3/genética , Caveolina 3/metabolismo , Modelos Animais de Doenças , Humanos , Músculo Esquelético/metabolismo , Distrofia Muscular do Cíngulo dos Membros/genética , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Distrofia Muscular do Cíngulo dos Membros/fisiopatologia , Distrofia Muscular do Cíngulo dos Membros/terapia , Mutação , Miostatina/antagonistas & inibidores , Miostatina/metabolismo , Fosforilação , Proteínas Smad/metabolismo , Transcrição Gênica/fisiologia , Fator de Crescimento Transformador beta/metabolismo
16.
Gene Ther ; 15(15): 1126-30, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18323791

RESUMO

RNA interference (RNAi) offers a novel therapeutic strategy based on the highly specific and efficient silencing of a target gene. Since it relies on small interfering RNAs (siRNAs), a major issue is the delivery of therapeutically active siRNAs into the target tissue/target cells in vivo. For safety reasons, strategies based on vector delivery may be of only limited clinical use. The more desirable approach is to directly apply active siRNAs in vivo. Here, we report the effectiveness of in vivo siRNA delivery into skeletal muscles of normal or diseased mice through nanoparticle formation of chemically unmodified siRNAs with atelocollagen (ATCOL). ATCOL-mediated local application of siRNA targeting myostatin, a negative regulator of skeletal muscle growth, in mouse skeletal muscles or intravenously, caused a marked increase in the muscle mass within a few weeks after application. These results imply that ATCOL-mediated application of siRNAs is a powerful tool for future therapeutic use for diseases including muscular atrophy.


Assuntos
Colágeno/genética , Terapia Genética/métodos , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/terapia , RNA Interferente Pequeno/administração & dosagem , Fator de Crescimento Transformador beta/genética , Animais , Imuno-Histoquímica , Injeções Intramusculares , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos mdx , Músculo Esquelético/patologia , Distrofia Muscular Animal/metabolismo , Distrofia Muscular Animal/patologia , Miostatina , Nanopartículas , Interferência de RNA , Fator de Crescimento Transformador beta/análise
17.
Cell Mol Life Sci ; 65(1): 64-72, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18030418

RESUMO

Nymphs of hemimetabolous insects such as cockroaches and crickets exhibit a remarkable capacity for regenerating complex structures from damaged legs. Until recent years, however, approaches to elucidate the molecular mechanisms underlying the leg regeneration process have been lacking. Taking the cricket Gryllus bimaculatus as a model, we found that a phenotype related to regeneration frequently appears during leg regeneration, even though no phenotype is induced by RNA interference (RNAi) in the cricket nymph, designated as regeneration-dependent RNAi. Since then, we have investigated the functions of various genes encoding signaling factors and cellular adhesion proteins like Fat and Dachsous during leg regeneration. In this review, we summarize the classical knowledge about insect leg regeneration and introduce recent advances concerning the signaling cascades required for regenerating a leg. Our results provide clues to the mechanisms of regeneration which are relevant to vertebrate systems.


Assuntos
Extremidades/fisiologia , Interferência de RNA , Regeneração/genética , Animais , Insetos , Ninfa , Transdução de Sinais
18.
Mini Rev Med Chem ; 6(11): 1255-61, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17100637

RESUMO

The transforming growth factor-beta (TGF-beta) superfamily includes TGF-betas, activin, myostatin and bone morphogenetic proteins. Misregulation of the activity of TGF-beta family members is involved in pathogenesis of cancer, muscular dystrophy, obesity and bone and tooth remodeling. Natural inhibitors for the TGF-beta superfamily regulate fine-tuning of activity of TGF-beta family in vivo. In addition to natural inhibitors for the TGF-beta family, soluble forms of receptors for the TGF-beta family, blocking monoclonal antibodies and small chemical TGF-beta inhibitors have been developed. In this review, we summarize recent advances in our understanding of inhibitors for the TGF-beta superfamily and their medical applications.


Assuntos
Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas Morfogenéticas Ósseas/metabolismo , Humanos , Doenças Musculares/tratamento farmacológico , Doenças Musculares/metabolismo , Miostatina , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Ligação Proteica , Fator de Crescimento Transformador beta/classificação
19.
Cytogenet Genome Res ; 112(3-4): 329-36, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16484791

RESUMO

The chromosomes derived from the Japanese population of Gryllus bimaculatus were characterized by C-banding and Ag-NOR staining. The chromosome number, 2n = 28 + XX (female)/XO (male), corresponded with that of other populations of G. bimaculatus, but the chromosome configuration in idiograms varied between the populations. NORs were carried on one pair of autosomes and appeared polymorphous. The positive C-bands located at the centromere of all chromosomes and the distal regions of many chromosome pairs, and the size and the distribution pattern of the distal C-heterochromatin showed differences among the chromosomes. In addition, this paper reports on the characteristics of HindIII satellite DNA isolated from the genome of G. bimaculatus. The HindIII repetitive fragments were about 0.54 kb long, and localized at the distal C-bands of the autosomes and the interstitial C-bands of the X chromosome. Molecular analysis showed two distinct satellite DNA sequences, named the GBH535 and GBH542 families, with high AT contents of about 67 and 66%, respectively. The two repetitive families seem to be derived from a common ancestral sequence, and both families possessed the same 13-bp palindrome sequence. The results of Southern blot hybridization suggest that the sequence of the GBH535 family is conserved in the genomic DNAs of Gryllus species, whereas the GBH542 family is a species-specific sequence.


Assuntos
DNA Satélite/genética , Gryllidae/genética , Telômero/genética , Telômero/ultraestrutura , Animais , Antígenos Nucleares/genética , Bandeamento Cromossômico , Mapeamento Cromossômico , Feminino , Japão , Cariotipagem , Masculino , Proteínas Nucleares/genética , Cromossomo X/genética , Cromossomo X/ultraestrutura , Cromossomo Y/genética , Cromossomo Y/ultraestrutura
20.
Eur Respir J ; 22(2): 213-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12952250

RESUMO

The inhalation of cyclosporin (Cs)A to the lung is limited by its hydrophobic properties. In order to improve the poor solubility of CsA, cyclodextrin (CD) was evaluated for its suitability for dry powder inhaler formation, and the benefit of an inhaled CsA/CD complex in vivo was demonstrated. The solubilising effect of CDs on CsA was measured by high-performance liquid chromatography. Ciliostatic activity and haemolysis were determined to assess some safety profiles of CDs. The efficacy of an inhaled CsA/CD complex was evaluated by eosinophil infiltration into the bronchoalveolar lavage fluid in actively sensitised mice. CDs markedly improved the poor solubility of CsA. The ciliostatic and haemolytic activities of maltosyl-alpha-CD were the weakest of all the tested CDs. CsA inhaled alone showed inhibitory effects on allergen-induced eosinophilia. Inhalation of the complex of CsA with maltosyl-alpha-CD, where the dose of CsA was approximately nine-times less than that of CsA inhaled alone, also inhibited eosinophil accumulation significantly, with a longer duration of action in comparison with the response to CsA alone. Thus the effective dose of cyclosporin A could be reduced by formation of a complex with maltosyl-alpha-cyclodextrin, and a wider therapeutic safety margin by inhalation of cyclosporin A as a complex with maltosyl-alpha-cyclodextrin could be expected.


Assuntos
Asma/tratamento farmacológico , Ciclodextrinas/administração & dosagem , Ciclodextrinas/química , Ciclosporina/administração & dosagem , Ciclosporina/química , Imunossupressores/administração & dosagem , Imunossupressores/química , Maltose/análogos & derivados , Maltose/administração & dosagem , Maltose/química , Administração por Inalação , Animais , Modelos Animais de Doenças , Quimioterapia Combinada , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pós , Solubilidade/efeitos dos fármacos
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