Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.422
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Phys Rev Lett ; 130(13): 132502, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37067317

RESUMO

The new isotope ^{241}U was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions of the ^{238}U+^{198}Pt system at the KISS facility. The present experimental results demonstrate the crucial role of the multinucleon transfer reactions for accessing unexplored neutron-rich actinide isotopes toward the N=152 shell gap in this region of nuclides.

2.
Phys Rev Lett ; 130(1): 012501, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36669221

RESUMO

The atomic masses of ^{55}Sc, ^{56,58}Ti, and ^{56-59}V have been determined using the high-precision multireflection time-of-flight technique. The radioisotopes have been produced at RIKEN's Radioactive Isotope Beam Factory (RIBF) and delivered to the novel designed gas cell and multireflection system, which has been recently commissioned downstream of the ZeroDegree spectrometer following the BigRIPS separator. For ^{56,58}Ti and ^{56-59}V, the mass uncertainties have been reduced down to the order of 10 keV, shedding new light on the N=34 shell effect in Ti and V isotopes by the first high-precision mass measurements of the critical species ^{58}Ti and ^{59}V. With the new precision achieved, we reveal the nonexistence of the N=34 empirical two-neutron shell gaps for Ti and V, and the enhanced energy gap above the occupied νp_{3/2} orbit is identified as a feature unique to Ca. We perform new Monte Carlo shell model calculations including the νd_{5/2} and νg_{9/2} orbits and compare the results with conventional shell model calculations, which exclude the νg_{9/2} and the νd_{5/2} orbits. The comparison indicates that the shell gap reduction in Ti is related to a partial occupation of the higher orbitals for the outer two valence neutrons at N=34.


Assuntos
Nêutrons , Titânio
3.
Rhinology ; 61(3): 263-271, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36891983

RESUMO

BACKGROUND: Tripartite motif-containing 27 (TRIM27) has been implicated in the progression of various cancers. However, the role of TRIM27 in sinonasal mucosal melanoma (SNMM) remains poorly understood. MATERIALS & METHODS: We retrospectively examined 28 patients with SNMM treated with between 2003 and 2021. We undertook immunohistochemical analysis of TRIM27, Ki-67, and p-Akt1 expression in SNMM tissues. We also investigated the relationship between TRIM27 expression and clinical characteristics, prognosis, Ki-67 as a tumor growth potential marker, and p-Akt1 as one of the prognostic factors in mucosal melanoma. RESULTS: TRIM27 expression was significantly higher in T4 disease than in T3 disease and was higher in stage IV than in stage III. Patients with high-TRIM27 SNMM had a significantly poorer prognosis in terms of overall survival (OS) and disease-free survival.There was also a significantly higher rate of distant metastasis. Univariate analysis for OS revealed that TRIM27 and T classification were significant poor prognostic factors. In addition, the Ki-67 positive score and the p-Akt1 total staining score were significantly higher in the high-TRIM27 group than in the low-TRIM27 group. CONCLUSIONS: High TRIM27 expression in SNMM was associated with advanced T classification, poor prognosis and distant metastasis. We suggest that TRIM27 has potential as a novel biomarker for prognosis in SNMM.


Assuntos
Melanoma , Neoplasias dos Seios Paranasais , Humanos , Estudos Retrospectivos , Antígeno Ki-67 , Neoplasias dos Seios Paranasais/patologia , Prognóstico , Proteínas de Ligação a DNA , Proteínas Nucleares
4.
Phys Rev Lett ; 129(21): 217201, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36461975

RESUMO

Optical absorption spectra in the visible and near-infrared light were measured for magnetoelectric spin glass Ni_{0.4}Mn_{0.6}TiO_{3} under various field-cooled conditions. Despite the absence of long-range magnetic-dipole order, this spin-glass system exhibits nonreciprocal directional dichroism (NDD) at zero external field after a magnetoelectric field-cooled procedure. This result is distinct from previous studies on NDD in systems with magnetic toroidal moments induced either by long-range magnetic-dipole order or by applying crossed electric and magnetic fields. The present Letter conclusively demonstrates that the observed NDD originates from magnetoelectrically induced ferroic order of magnetic toroidal moments without conventional magnetic-dipole order.

5.
Nanotechnology ; 33(30)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35395650

RESUMO

We report on the characterization of wurtzite (WZ) InP nanowire (NW) light-emitting diodes (LEDs) with different pn junctions (axial and radial). The series resistance tended to be smaller in the NW-LED using core-shell InP NWs with a radial pn junction than in the NW-LED using InP NWs with an axial pn junction, indicating that radial pn junctions are more suitable for current injection. The electroluminescence (EL) properties of both NW LEDs revealed that the EL had three peaks originating from the zinc-blende (ZB) phase, WZ phase, and ZB/WZ heterojunction. Transmission electron microscopy showed that the dominant EL in the radial pn junction originated from the ZB/WZ interface across the stacking faults.

6.
Phys Rev Lett ; 127(7): 077201, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34459637

RESUMO

We report ^{51}V NMR and inelastic neutron scattering (INS) measurements on a quasi-1D antiferromagnet BaCo_{2}V_{2}O_{8} under transverse field along the [010] direction. The scaling behavior of the spin-lattice relaxation rate above the Néel temperatures unveils a 1D quantum critical point (QCP) at H_{c}^{1D}≈4.7 T, which is masked by the 3D magnetic order. With the aid of accurate analytical analysis and numerical calculations, we show that the zone center INS spectrum at H_{c}^{1D} is precisely described by the pattern of the 1D quantum Ising model in a magnetic field, a class of universality described in terms of the exceptional E_{8} Lie algebra. These excitations are nondiffusive over a certain field range when the system is away from the 1D QCP. Our results provide an unambiguous experimental realization of the massive E_{8} phase in the compound, and open a new experimental route for exploring the dynamics of quantum integrable systems as well as physics beyond integrability.

7.
Ann Vasc Surg ; 75: 531.e7-531.e13, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33836232

RESUMO

The management of abdominal aortic aneurysms (AAA) has evolved significantly with the advent of endovascular strategies. Thus, there has been a decline in the number of open AAA repairs once an endovascular option is available. There have also been reports of successful endovascular management of infective native aortic aneurysms (INAA)1, previously called mycotic aneurysms2. The rarity of this condition makes its management a challenging one as there are no standard guidelines. The European Society of Vascular Surgery has suggested that the nomenclature be changed from mycotic aneurysms as this can be misleading to standardise reporting1. The authors' present a case of a 67-year old male who presented during the peak of the Corona Virus pandemic with constitutional gastrointestinal symptoms. He was subsequently diagnosed with an INAA and successfully managed with open Neo-Aorto Iliac System reconstruction with a homograft3. The report highlights various strategies used in the surgical approach and their benefits in the management of INAA. Furthermore, a literature review of Streptococcus (Streptococcus agalactiae) species as a rare cause of INAA and how these cases were managed are also highlighted.


Assuntos
Aneurisma Infectado/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Artéria Ilíaca/transplante , Infecções Estreptocócicas/cirurgia , Streptococcus agalactiae/isolamento & purificação , Enxerto Vascular , Idoso , Aloenxertos , Aneurisma Infectado/diagnóstico , Aneurisma Infectado/microbiologia , Antibacterianos/uso terapêutico , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/microbiologia , Humanos , Masculino , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Resultado do Tratamento
8.
Int Endod J ; 54(9): 1614-1622, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33527449

RESUMO

AIM: To evaluate how different rotational speeds affect the torque/force generation and shaping ability of rotary root canal instrumentation using JIZAI (MANI, Utsunomiya, Japan) nickel-titanium instruments in continuous rotation and optimum torque reverse (OTR) motion. METHODOLOGY: Mesial root canals of extracted mandibular molars were instrumented up to size 25, 0.04 taper using JIZAI instruments, and anatomically matched canals were selected based on geometric features of the canal [canal volume (mm3 ), surface area (mm2 ), length, 15°-20° curvature and radius of curvature (4-8 mm)] after micro-computed tomographic scanning. An automated root canal instrumentation and torque/force analysing device was programmed to permit a simulated pecking motion (2 s downward and 1 s upward at 50 mm min-1 ). The selected canals were prepared with size 25, 0.06 taper JIZAI instruments using continuous rotation or OTR motion and further subdivided according to the rotational speed (300 or 500 rpm, n = 10 each). Real-time clockwise/counterclockwise torque and downward/upward force were recorded using a custom-made torque/force analysing device. Then, the registered pre- and post-operative micro-computed tomographic datasets were examined to evaluate the canal volume changes and centring ratios at 1, 3, 5 and 7 mm from the apical foramen. Data were analysed using two-way analysis of variance or the Kruskal-Wallis test and Mann-Whitney U test with Bonferroni correction (α = 5%). RESULTS: Maximum upward force and clockwise torque were significantly smaller in 500 rpm groups than in 300 rpm groups (P < .05); however, no significant difference was found between continuous rotation and OTR motion (P > .05). OTR motion developed higher maximum counterclockwise torque than continuous rotation (P < .05). Maximum downward force, canal volume changes and centring ratios were not significantly different among all groups (P > .05). There was no file fracture in any of the groups. CONCLUSIONS: Under laboratory conditions using JIZAI instruments, a rotational speed of 500 rpm generated significantly lower maximum screw-in forces and torque values than rotational speed of 300 rpm. Continuous rotation and OTR motion performed similarly in shaping the canals.


Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Ligas Dentárias , Cavidade Pulpar/diagnóstico por imagem , Desenho de Equipamento , Humanos , Rotação , Titânio , Torque
9.
J Appl Microbiol ; 127(3): 932-940, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31211883

RESUMO

AIMS: Equol is a nonsteroidal oestrogen of the isoflavone class. We investigated the antibacterial ability of equol with respect to the growth rate, toxin production and spore-forming abilities of Clostridioides difficile BI/027/NAP1. METHODS AND RESULTS: Isoflavones, or female hormones, were added to bacterial culture, which was grown at 35°C. The absorbance of the culture was measured at various time points for evaluating the growth inhibition. The toxin levels in the media and morphological changes were also assessed. To evaluate the influence of equol on the sporulation of C. difficile, cells were collected at various time points from the equol-supplemented culture and the number of spores was counted. Our results show that equol inhibits bacterial growth in a concentration-dependent manner. However, it does not inhibit the production of toxin by C. difficile. Other isoflavones and female hormones did not inhibit the C. difficile growth. At the 14th day, approximately 600 spores were present in the control medium and only six were seen in the equol-containing medium. CONCLUSION: Our results suggest that equol may directly inhibit the C. difficile growth in a concentration-dependent manner and spore formation. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on the antimicrobial ability of equol.


Assuntos
Antibacterianos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Equol/farmacologia , Antibacterianos/química , Clostridioides difficile/crescimento & desenvolvimento , Clostridioides difficile/metabolismo , Equol/química , Testes de Sensibilidade Microbiana , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/crescimento & desenvolvimento
11.
Phys Rev Lett ; 120(15): 152501, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756864

RESUMO

The masses of ^{246}Es, ^{251}Fm, and the transfermium nuclei ^{249-252}Md and ^{254}No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed N=152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of ^{246}Es and ^{249,250,252}Md were measured for the first time. Using the masses of ^{249,250}Md as anchor points for α decay chains, the masses of heavier nuclei, up to ^{261}Bh and ^{266}Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter δ_{2n} derived from three isotopic masses was updated with the new masses and corroborates the existence of the deformed N=152 neutron shell closure for Md and Lr.

12.
Osteoporos Int ; 28(3): 1109-1119, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27796444

RESUMO

This study investigated the effects of raloxifene and alendronate to follow parathyroid hormone (PTH) on bone collagen and biomechanical properties in ovariectomized rabbits. Sequential treatments of raloxifene and alendronate after hPTH(1-34) treatment improved biomechanical properties with and without bone collagen improvement, respectively. INTRODUCTION: The standard sequential treatment to follow human parathyroid hormone (hPTH) (1-34) therapy for osteoporosis has yet to be determined. The objective of this study was to compare the effects of raloxifene and alendronate treatments to follow daily hPTH(1-34) treatment on non-enzymatic collagen cross-links, bone mass, and bone strength in ovariectomized (OVX) rabbits. METHODS: From 3 months after ovariectomy, seven month-old female New Zealand white rabbits were given either vehicle or hPTH(1-34) (8 µg/kg/day), once daily for 5 months. After hPTH(1-34) treatment, the hPTH(1-34)-treated animals were divided into two groups, and given raloxifene (10 mg/kg, daily) orally or alendronate (100 µg/kg, twice weekly) subcutaneously for 5 months. We evaluated bone mineral density (BMD), bone structural parameters, advanced glycation end product (AGE) content in collagen, and bone mechanical parameters including intrinsic parameters in the femur. RESULTS: Raloxifene (hPTH/RLX) and alendronate (hPTH/ALN) to follow hPTH(1-34) increased cortical thickness, maximum load, and maximum stress and decreased endocortical surface in the diaphysis, in addition to increasing total BMD in the distal metaphysis. Decreased trabecular AGE, pentosidine, and homocysteine contents and increased toughness and breaking energy were noted with hPTH/RLX treatment only. With hPTH/ALN treatment, no effects on non-enzymatic collagen cross-link AGEs were noted although increases in stiffness and elastic modulus were observed. CONCLUSION: These results suggest that sequential treatments with hPTH(1-34) and antiresorptive drugs (raloxifene and alendronate) have a beneficial effect on bone mass and biomechanical properties in OVX rabbits.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Densidade Óssea/efeitos dos fármacos , Colágeno/efeitos dos fármacos , Alendronato/administração & dosagem , Alendronato/farmacologia , Animais , Biomarcadores/metabolismo , Fenômenos Biomecânicos , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/administração & dosagem , Colágeno/metabolismo , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Feminino , Fêmur/efeitos dos fármacos , Fêmur/patologia , Fêmur/fisiopatologia , Produtos Finais de Glicação Avançada/efeitos dos fármacos , Produtos Finais de Glicação Avançada/metabolismo , Ovariectomia , Coelhos , Cloridrato de Raloxifeno/administração & dosagem , Cloridrato de Raloxifeno/farmacologia , Estresse Mecânico , Teriparatida/farmacologia , Suporte de Carga
13.
J Chem Inf Model ; 57(6): 1388-1401, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28537745

RESUMO

In recent years, molecular dynamics simulations of proteins in explicit mixed solvents have been applied to various problems in protein biophysics and drug discovery, including protein folding, protein surface characterization, fragment screening, allostery, and druggability assessment. In this study, we perform a systematic study on how mixtures of organic solvent probes in water can reveal cryptic ligand binding pockets that are not evident in crystal structures of apo proteins. We examine a diverse set of eight PDB proteins that show pocket opening induced by ligand binding and investigate whether solvent MD simulations on the apo structures can induce the binding site observed in the holo structures. The cosolvent simulations were found to induce conformational changes on the protein surface, which were characterized and compared with the holo structures. Analyses of the biological systems, choice of probes and concentrations, druggability of the resulting induced pockets, and application to drug discovery are discussed here.


Assuntos
Simulação de Dinâmica Molecular , Proteínas/química , Proteínas/metabolismo , Solventes/química , Sítios de Ligação , Conformação Proteica
14.
Clin Genet ; 90(6): 526-535, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27434533

RESUMO

Joubert syndrome (JS) is rare recessive disorders characterized by the combination of hypoplasia/aplasia of the cerebellar vermis, thickened and elongated superior cerebellar peduncles, and a deep interpeduncular fossa which is defined by neuroimaging and is termed the 'molar tooth sign'. JS is genetically highly heterogeneous, with at least 29 disease genes being involved. To further understand the genetic causes of JS, we performed whole-exome sequencing in 24 newly recruited JS families. Together with six previously reported families, we identified causative mutations in 25 out of 30 (24 + 6) families (83.3%). We identified eight mutated genes in 27 (21 + 6) Japanese families, TMEM67 (7/27, 25.9%) and CEP290 (6/27, 22.2%) were the most commonly mutated. Interestingly, 9 of 12 CEP290 disease alleles were c.6012-12T>A (75.0%), an allele that has not been reported in non-Japanese populations. Therefore c.6012-12T>A is a common allele in the Japanese population. Importantly, one Japanese and one Omani families carried compound biallelic mutations in two distinct genes (TMEM67/RPGRIP1L and TMEM138/BBS1, respectively). BBS1 is the causative gene in Bardet-Biedl syndrome. These concomitant mutations led to severe and/or complex clinical features in the patients, suggesting combined effects of different mutant genes.


Assuntos
Anormalidades Múltiplas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Antígenos de Neoplasias/genética , Cerebelo/anormalidades , Anormalidades do Olho/genética , Doenças Renais Císticas/genética , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Retina/anormalidades , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/fisiopatologia , Alelos , Proteínas de Ciclo Celular , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Proteínas do Citoesqueleto , Anormalidades do Olho/diagnóstico por imagem , Anormalidades do Olho/epidemiologia , Anormalidades do Olho/fisiopatologia , Feminino , Heterogeneidade Genética , Predisposição Genética para Doença , Humanos , Japão/epidemiologia , Doenças Renais Císticas/diagnóstico por imagem , Doenças Renais Císticas/epidemiologia , Doenças Renais Císticas/fisiopatologia , Masculino , Mutação , Omã/epidemiologia , Linhagem , Retina/diagnóstico por imagem , Retina/fisiopatologia
15.
Phys Rev Lett ; 117(5): 056403, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27517783

RESUMO

We present an angle-resolved photoemission study of the electronic structure of the three-dimensional pyrochlore iridate Nd_{2}Ir_{2}O_{7} through its magnetic metal-insulator transition. Our data reveal that metallic Nd_{2}Ir_{2}O_{7} has a quadratic band, touching the Fermi level at the Γ point, similar to that of Pr_{2}Ir_{2}O_{7}. The Fermi node state is, therefore, a common feature of the metallic phase of the pyrochlore iridates. Upon cooling below the transition temperature, this compound exhibits a gap opening with an energy shift of quasiparticle peaks like a band gap insulator. The quasiparticle peaks are strongly suppressed, however, with further decrease of temperature, and eventually vanish at the lowest temperature, leaving a nondispersive flat band lacking long-lived electrons. We thereby identify a remarkable crossover from Slater to Mott insulators with decreasing temperature. These observations explain the puzzling absence of Weyl points in this material, despite its proximity to the zero temperature metal-insulator transition.

17.
Proteins ; 83(2): 331-50, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25401969

RESUMO

HIV-1 gp120 undergoes multiple conformational changes both before and after binding to the host CD4 receptor. BMS-626529 is an attachment inhibitor (AI) in clinical development (administered as prodrug BMS-663068) that binds to HIV-1 gp120. To investigate the mechanism of action of this new class of antiretroviral compounds, we constructed homology models of unliganded HIV-1 gp120 (UNLIG), a pre-CD4 binding-intermediate conformation (pCD4), a CD4 bound-intermediate conformation (bCD4), and a CD4/co-receptor-bound gp120 (LIG) from a series of partial structures. We also describe a simple pathway illustrating the transition between these four states. Guided by the positions of BMS-626529 resistance substitutions and structure-activity relationship data for the AI series, putative binding sites for BMS-626529 were identified, supported by biochemical and biophysical data. BMS-626529 was docked into the UNLIG model and molecular dynamics simulations were used to demonstrate the thermodynamic stability of the different gp120 UNLIG/BMS-626529 models. We propose that BMS-626529 binds to the UNLIG conformation of gp120 within the structurally conserved outer domain, under the antiparallel ß20-ß21 sheet, and adjacent to the CD4 binding loop. Through this binding mode, BMS-626529 can inhibit both CD4-induced and CD4-independent formation of the "open state" four-stranded gp120 bridging sheet, and the subsequent formation and exposure of the chemokine co-receptor binding site. This unique mechanism of action prevents the initial interaction of HIV-1 with the host CD4+ T cell, and subsequent HIV-1 binding and entry. Our findings clarify the novel mechanism of BMS-626529, supporting its ongoing clinical development.


Assuntos
Proteína gp120 do Envelope de HIV/química , Inibidores da Fusão de HIV/química , Piperazinas/química , Triazóis/química , Sítios de Ligação , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Ligação Proteica , Homologia Estrutural de Proteína , Relação Estrutura-Atividade
18.
Phys Rev Lett ; 115(10): 106803, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382694

RESUMO

We performed high-resolution photon-energy and polarization-dependent ARPES measurements on ultrathin Bi(111) films [6-180 bilayers (BL), 2.5-70 nm thick] formed on Si(111). In addition to the extensively studied surface states (SSs), the edge of the bulk valence band was clearly measured by using S-polarized light. We found direct evidence that this valence band edge, which forms a hole pocket in the bulk Bi crystal, does not cross the Fermi level for the 180 BL thick film. This is consistent with the predicted semimetal-to-semiconductor transition due to the quantum-size effect [V.B. Sandomirskii, Sov. Phys. JETP 25, 101 (1967)]. However, it became metallic again when the film thickness was decreased (below 30 BL). A plausible explanation for this phenomenon is the modification of the charge neutrality condition due to the size effect of the SSs.

19.
Phys Rev Lett ; 115(26): 267207, 2015 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-26765023

RESUMO

We experimentally demonstrate one-way transparency of light in multiferroic CuB(2)O(4). The material is rendered transparent for light propagating in one direction, while opaque for light propagating in the opposite direction. The novel transparency results from a destructive interference of the electric dipole and magnetic dipole transitions. The realization of the effect has been accomplished by the application of a high magnetic field and the proper selection of the propagation direction of light in agreement with our quantum mechanical formulation of nonreciprocal directional dichroism.

20.
Eur J Clin Microbiol Infect Dis ; 34(5): 951-61, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25577175

RESUMO

We compared the expected medical costs of empirical and preemptive treatment strategies for invasive fungal infection in neutropenic patients with hematological diseases. Based on the results of two clinical trials with different backgrounds reported by Oshima et al. [J Antimicrob Chemother 60(2):350-355; Oshima study] and Cordonnier et al. [Clin Infect Dis 48(8):1042-1051; PREVERT study], we developed a decision tree model that represented the outcomes of empirical and preemptive treatment strategies, and estimated the expected medical costs of medications and examinations in the two strategies. We assumed that micafungin was started in the empirical group at 5 days after fever had developed, while voriconazole was started in the preemptive group only when certain criteria, such as positive test results of imaging studies and/or serum markers, were fulfilled. When we used an incidence of positive test results of 6.7 % based on the Oshima study, the expected medical costs of the empirical and preemptive groups were 288,198 and 150,280 yen, respectively. Even in the case of the PREVERT study, in which the incidence of positive test results was 32.9 %, the expected medical costs in the empirical and preemptive groups were 291,871 and 284,944 yen, respectively. A sensitivity analysis indicated that the expected medical costs in the preemptive group would exceed those in the empirical group when the incidence of positive test results in the former was over 34.4 %. These results suggest that a preemptive treatment strategy can be expected to reduce medical costs compared with empirical therapy in most clinical settings.


Assuntos
Antifúngicos/economia , Quimioprevenção/economia , Quimioprevenção/métodos , Testes Diagnósticos de Rotina/economia , Doenças Hematológicas/complicações , Micoses/prevenção & controle , Neutropenia/complicações , Antifúngicos/administração & dosagem , Ensaios Clínicos como Assunto , Análise Custo-Benefício , Testes Diagnósticos de Rotina/métodos , Equinocandinas/administração & dosagem , Equinocandinas/economia , Humanos , Lipopeptídeos/administração & dosagem , Lipopeptídeos/economia , Micafungina , Micoses/diagnóstico , Estudos Retrospectivos , Voriconazol/administração & dosagem , Voriconazol/economia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA