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1.
Pharmaceutics ; 15(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37376145

RESUMO

The conventional dosage form of Ethyol® (amifostine), a sterile lyophilized powder, involves reconstituting it with 9.7 mL of sterile 0.9% sodium chloride in accordance with the United States Pharmacopeia specifications for intravenous infusion. The purpose of this study was to develop inhalable microparticles of amifostine (AMF) and compare the physicochemical properties and inhalation efficiency of AMF microparticles prepared by different methods (jet milling and wet ball milling) and different solvents (methanol, ethanol, chloroform, and toluene). Inhalable microparticles of AMF dry powder were prepared using a wet ball-milling process with polar and non-polar solvents to improve their efficacy when delivered through the pulmonary route. The wet ball-milling process was performed as follows: AMF (10 g), zirconia balls (50 g), and solvent (20 mL) were mixed and placed in a cylindrical stainless-steel jar. Wet ball milling was performed at 400 rpm for 15 min. The physicochemical properties and aerodynamic characteristics of the prepared samples were evaluated. The physicochemical properties of wet-ball-milled microparticles (WBM-M and WBM-E) using polar solvents were confirmed. Aerodynamic characterization was not used to measure the % fine particle fraction (% FPF) value in the raw AMF. The % FPF value of JM was 26.9 ± 5.8%. The % FPF values of the wet-ball-milled microparticles WBM-M and WBM-E prepared using polar solvents were 34.5 ± 0.2% and 27.9 ± 0.7%, respectively; while the % FPF values of the wet-ball-milled microparticles WBM-C and WBM-T prepared using non-polar solvents were 45.5 ± 0.6% and 44.7 ± 0.3%, respectively. Using a non-polar solvent in the wet ball-milling process resulted in a more homogeneous and stable crystal form of the fine AMF powder than using a polar solvent.

2.
ACS Appl Mater Interfaces ; 15(23): 28064-28072, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37218997

RESUMO

All-solid-state batteries (ASBs) have been identified as a potential next-generation technology for safe energy storage. However, the current pellet form of solid electrolytes (SEs) exhibits low cell-level energy densities and mechanical brittleness, and this has hampered the commercialization of ASBs. In this work, we report on the development of an ultrathin SE membrane that can be reduced to a thickness of 31 µm with minimal thermal shrinkage at 140 °C, while exhibiting robust mechanical properties (tensile strength of 19.6 MPa). Due to its exceptional ionic conductivity of 0.55 mS/cm and the corresponding areal conductance of 84 mS/cm2, the SE membrane-incorporated ASB displays cell-level gravimetric and volumetric energy densities of 127.9 Wh/kgcell and 140.7 Wh/Lcell, respectively. These values represent a 7.6- and 5.7-fold increase over those achieved with conventional SE pellet cells. Our results demonstrate the potential of the developed SE membrane to overcome the critical challenges in the commercialization of ASBs.

3.
ACS Appl Mater Interfaces ; 15(10): 13131-13143, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791219

RESUMO

Problematic issues with electrically inert binders have been less serious in the conventional lithium-ion batteries by virtue of permeable liquid electrolytes (LEs) for ionic connection and/or carbonaceous additives for electronic connection in the electrodes. Contrary to electron-conductive binders used to maximize an active loading level, the development of ion-conductive binders has been lacking owing to the LE-filled electrode configuration. Herein, we represent a tactical strategy for improving the interfacial Li+ conduction in all-solid-state electrolyte-free graphite (EFG) electrodes where the solid electrolytes are entirely excluded, using lithium-substitution-modulated (LSM) binders. Finely tuning a lithium substitution ratio, a conductive LSM-carboxymethyl cellulose (CMC) binder is prepared from a controlled direct Na+/Li+ exchange reaction without a hazardous acid involvement. The EFG electrode employing LSM with a maximum degree of substitution of lithium (DSLi) of ∼68% in our study shows a considerably higher rate capability of 1.05 mA h cm-2 at 1 C and a capacity retention of ∼61.9% after 200 cycles at 0.5 C than those using sodium-CMC (Na-CMC) (0.78 mA h cm-2, ∼49.5%) and LSM with ∼35% lithium substitution (0.93 mA h cm-2, ∼55.4%). More importantly, the correlation between the phase transition near the bottom region of the EFG electrode and the state of charge (SOC) is systematically investigated, clarifying that the improvement of the interfacial conduction is proportional to the DSLi of the CMC binders. Theoretical calculations combined with experimental results further verify that creating the continuous interface through abundant pathways for mobile ions using the Li+-conductive binder is the enhancement mechanism of the interfacial conduction in the EFG electrode, mitigating serious charge transfer resistance.

4.
Science ; 372(6547): 1187-1191, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34112690

RESUMO

Ammonia (NH3) is a globally important commodity for fertilizer production, but its synthesis by the Haber-Bosch process causes substantial emissions of carbon dioxide. Alternative, zero-carbon emission NH3 synthesis methods being explored include the promising electrochemical lithium-mediated nitrogen reduction reaction, which has nonetheless required sacrificial sources of protons. In this study, a phosphonium salt is introduced as a proton shuttle to help resolve this limitation. The salt also provides additional ionic conductivity, enabling high NH3 production rates of 53 ± 1 nanomoles per second per square centimeter at 69 ± 1% faradaic efficiency in 20-hour experiments under 0.5-bar hydrogen and 19.5-bar nitrogen. Continuous operation for more than 3 days is demonstrated.

5.
J Vet Pharmacol Ther ; 44(3): 342-348, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33295645

RESUMO

The oral disintegrating film (ODF) has advantages over suspension and tablet. These include convenience of administration, patient compliance, and accurate dosing. We evaluated the bioequivalence between the ODF and the meloxicam suspension by using a crossover design with a 3-week washout period. Six healthy male beagle dogs were randomized to receive both formulations of meloxicam, 2 mg. Plasma meloxicam concentrations were measured at the same times. From the start until maximum concentration, the initial absorption of the ODF meloxicam formulation was more rapid (2.08 ± 1.56 hr) as compared to the suspension (3.33 ± 1.03 hr). Mean elimination half-lives were 28.77 ± 4.01 and 32.85 ± 9.79 hr for the ODF and the suspension, respectively. Bioequivalence of the ODF was confirmed, based on the relative ratios of geometric mean concentrations (and 90% confidence intervals within the range of 80%-125%) for a maximum concentration of 101.05% (88.59-115.25), for the area under the plasma concentration-time curve (AUC) to the last sampling time of 96.07% (87.06-115.25), and for AUC to infinity of 92.65% (86.76-98.94). The meloxicam ODF may be used as an alternative to suspension formulations in the treatment of inflammatory joint diseases and painful musculoskeletal disorders.


Assuntos
Meloxicam , Administração Oral , Animais , Área Sob a Curva , Estudos Cross-Over , Cães , Masculino , Comprimidos , Equivalência Terapêutica
6.
Nat Commun ; 11(1): 5546, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33144566

RESUMO

Ammonia is of emerging interest as a liquefied, renewable-energy-sourced energy carrier for global use in the future. Electrochemical reduction of N2 (NRR) is widely recognised as an alternative to the traditional Haber-Bosch production process for ammonia. However, though the challenges of NRR experiments have become better understood, the reported rates are often too low to be convincing that reduction of the highly unreactive N2 molecule has actually been achieved. This perspective critically reassesses a wide range of the NRR reports, describes experimental case studies of potential origins of false-positives, and presents an updated, simplified experimental protocol dealing with the recently emerging issues.

7.
Drug Dev Ind Pharm ; 46(5): 852-860, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32338551

RESUMO

Metformin hydrochloride (MFM) is often used as a controlled-release (CR) tablet to reduce dosing frequency. However, the MFM CR tablet contains significant amounts of excipients and the tablet size is also large. Dosing convenience and patient compliance can be increased by reducing the size of the CR tablets. The aim of this study was to prepare and evaluate the MFM controlled-release tablet (MFM-CRT) using two types of release modulators, inner and outer. The MFM-CRT was prepared by coating the MFM granules using a binder solution containing aluminum stearate (ALS) as the inner release-modulator, and polyethylene oxide (PEO) as the outer release-modulator. The dispersion stability of the binder solution was optimized by the dispersion analyzer. The MFM-CRT was evaluated for dissolution rate and tablet volume. Additionally, dissolution behavior and dissolution kinetics of the MFM-CRT were analyzed using micro-computed tomography (micro-CT). Although the optimal MFM-CRT showed no difference in the release rate as compared to the commercially available product of Glucophage® XR 500 mg (f2 value: 72), the length of the long axis was reduced by 6 mm and the weight was reduced by about 27%. We expect patient compliance to improve because of effective sustained release and volume reduction of MFM-CRT.


Assuntos
Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Ácidos Graxos/síntese química , Hipoglicemiantes/síntese química , Metformina/síntese química , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/metabolismo , Portadores de Fármacos/metabolismo , Ácidos Graxos/metabolismo , Hipoglicemiantes/metabolismo , Metformina/metabolismo , Espectrometria por Raios X/métodos , Microtomografia por Raio-X/métodos
8.
Adv Mater ; 32(18): e1904804, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31762106

RESUMO

It has become apparent that renewable energy sources are plentiful in many, often remote, parts of the world, such that storing and transporting that energy has become the key challenge. For long-distance transportation by pipeline and bulk tanker, a liquid form of energy carrier is ideal, focusing attention on liquid hydrogen and ammonia. Development of high-activity and selectivity electrocatalyst materials to produce these energy carriers by reductive electrochemistry has therefore become an important area of research. Here, recent developments and challenges in the field of electrocatalytic materials for these processes are discussed, including the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and the nitrogen reduction reaction (NRR). Some of the mis-steps currently plaguing the nitrogen reduction to ammonia field are highlighted. The rapidly growing roles that in situ/operando and quantum chemical studies can play in new electromaterials discovery are also surveyed.

9.
ChemSusChem ; 13(5): 929-937, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-31880398

RESUMO

Metal-N-C is a type of attractive electrocatalyst for efficient CO2 reduction to CO. Because of the ambiguity in their atomic structures, the active sites and catalytic mechanisms of the catalysts have remained under debate. Here, the effects of N and C hybrid coordination on the activity of Ni-N-C catalysts were investigated, combining theoretical and experimental methods. The theoretical calculations revealed that N and C hybrid coordination greatly enhanced the capability of single-atom Ni active sites to provide electrons to reactant molecules and strengthens the bonding of Ni to N and C in the Ni-N-C complexes. During the reaction process, the C and N coordination synergistically optimized the reaction energies in the conversion of CO2 to CO. A good agreement between theoretical calculations and electrochemical experiments was achieved based on the newly developed Ni-N-C electrocatalysts. The activity of hybrid-coordination NiN2 C2 was more than double that of single-coordination NiN4 .

10.
Nat Commun ; 10(1): 1367, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894529

RESUMO

The original version of this Article contained errors in the author affiliations. Affiliation 1 incorrectly read 'School of Chemical Engineering, University of New South Wales (UNSW), Sydney, NSW 2031, Australia' and affiliation 4 incorrectly read 'School of Engineering, RMIT University, Melbourne, VIC 3001, Australia.' This has now been corrected in both the PDF and HTML versions of the Article.

11.
Nat Commun ; 10(1): 865, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808867

RESUMO

Negative carbon emission technologies are critical for ensuring a future stable climate. However, the gaseous state of CO2 does render the indefinite storage of this greenhouse gas challenging. Herein, we created a liquid metal electrocatalyst that contains metallic elemental cerium nanoparticles, which facilitates the electrochemical reduction of CO2 to layered solid carbonaceous species, at a low onset potential of -310 mV vs CO2/C. We exploited the formation of a cerium oxide catalyst at the liquid metal/electrolyte interface, which together with cerium nanoparticles, promoted the room temperature reduction of CO2. Due to the inhibition of van der Waals adhesion at the liquid interface, the electrode was remarkably resistant to deactivation via coking caused by solid carbonaceous species. The as-produced solid carbonaceous materials could be utilised for the fabrication of high-performance capacitor electrodes. Overall, this liquid metal enabled electrocatalytic process at room temperature may result in a viable negative emission technology.

12.
Chemphyschem ; 19(13): 1627-1634, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29603536

RESUMO

Polymeric binder distribution within electrodes is crucial to guarantee the electrochemical performance of lithium-ion batteries (LIBs) for their long-term use in applications such as electric vehicles and energy-storage systems. However, due to limited analytical tools, such analyses have not been conducted so far. Herein, the adhesion properties of LIB electrodes at different depths are measured using a surface and interfacial cutting analysis system (SAICAS). Moreover, two LiCoO2 electrodes, dried at 130 and 230 °C, are carefully prepared and used to obtain the adhesion properties at every 10 µm of depth as well as the interface between the electrode composite and the current collector. At high drying temperatures, more of the polymeric binder material and conductive agent appears adjacent to the electrode surface, resulting in different adhesion properties as a function of depth. When the electrochemical properties are evaluated at different temperatures, the LiCoO2 electrode dried at 130 °C shows a much better high-temperature cycling performance than does the electrode dried at 230 °C due to the uniform adhesion properties and the higher interfacial adhesion strength.

14.
Ann Hematol ; 96(1): 17-23, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27677489

RESUMO

Tumor necrosis (TN) can lower responsiveness to chemotherapy and confer basic resistance to anti-cancer therapy. We investigated the association of TN with poor clinical features and outcome in diffuse large B cell lymphoma (DLBCL). We examined the presence or absence of TN in 476 DLBCL patients of who received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy. Eighty-nine (18.7 %) patients had TN at diagnosis. Patients with TN had a progression-free survival (PFS) and overall survival (OS) of 39.3 and 46.7 %, whereas patients without TN had a PFS and OS of 73.4 and 82.6 %. Adverse clinical factors of poor Eastern Cooperative Oncology Group performance status ≥ grade 2 (p = 0.005), elevated lactate dehydrogenase ratio >1 (p < 0.001), advanced Ann Arbor stage (p = 0.002), and bulky disease (p = 0.026) were more prevalent in the TN group than the non-TN group. Cox regression model analysis revealed TN as an independent prognostic factor for PFS and OS in DLBCL (PFS, hazard ratio [HR] = 1.967, 95 % confidence interval [CI] = 1.399-2.765, p < 0.001; OS, HR = 2.445, 95 % CI = 1.689-3.640, p < 0.001). The results indicate that TN could reflect adverse clinical features and worse prognosis in DLBCL patients receiving R-CHOP therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Progressão da Doença , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Humanos , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Necrose/diagnóstico por imagem , Necrose/tratamento farmacológico , Necrose/mortalidade , Prednisona/administração & dosagem , Rituximab , Resultado do Tratamento , Vincristina/administração & dosagem
15.
Chemistry ; 22(40): 14158-61, 2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27464300

RESUMO

The efficient and selective catalytic reduction of CO2 is a highly promising process for both of the storage of renewable energy as well as the production of valuable chemical feedstocks. In this work, we show that the addition of an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate, in an aprotic electrolyte containing a proton source and FeTPP, promotes the in situ formation of the [Fe(0) TPP](2-) homogeneous catalyst at a less negative potential, resulting in lower overpotentials for the CO2 reduction (670 mV) and increased kinetics of electron transfer. This co-catalysis exhibits high Faradaic efficiency for CO production (93 %) and turnover number (2 740 000 after 4 hour electrolysis), with a four-fold increase in turnover frequency (TOF) when compared with the standard system without the ionic liquid.

16.
Int J Hematol ; 104(4): 476-84, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27349913

RESUMO

Although splenomegaly is major characteristic of primary myelofibrosis (PMF), splenomegaly has been devalued due to a less reliable method based on physical examination (PEx). We evaluated whether spleen volume (SV) on CT would accurately predict clinical outcomes in PMF. A total of 188 patients were enrolled. SV was quantitated by the automatic volume software. In ROC curve, the SV predicted prognosis more accurately than spleen length by PEx (p < 0.001). The ideal cut-off value was 378.1 cm(3) for SV, which was divided into high- and low-volume status. Patients with low SV status had superior leukemia-free survival and overall survival compared to high SV status (p < 0.001, p < 0.001) In the Cox analysis, old age ≥65 years (p = 0.004, p = 0.001), low Hemoglobin <10.0 g/dL (p = 0.023, p = 0.021), high WBC counts ≥25 × 10(9)/L (p = 0.003, p = 0.006), peripheral blasts ≥1 % (p = 0.029, p = 0.020), unfavorable cytogenetic abnormalities (p = 0.025, p = 0.028), and high SV status (p = 0.004, p = 0.003) were independently associated with survivals. SV measured by CT was important for predicting survival in patients with PMF.


Assuntos
Mielofibrose Primária/diagnóstico , Baço/patologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Humanos , Pessoa de Meia-Idade , Tamanho do Órgão , Mielofibrose Primária/mortalidade , Prognóstico , Software , Taxa de Sobrevida , Tomografia Computadorizada por Raios X/normas
17.
ACS Appl Mater Interfaces ; 7(27): 14851-8, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26075943

RESUMO

A highly adhesive and thermally stable copolyimide (P84) that is soluble in organic solvents is newly applied to silicon (Si) anodes for high energy density lithium-ion batteries. The Si anodes with the P84 binder deliver not only a little higher initial discharge capacity (2392 mAh g(-1)), but also fairly improved Coulombic efficiency (71.2%) compared with the Si anode using conventional polyvinylidene fluoride binder (2148 mAh g(-1) and 61.2%, respectively), even though P84 is reduced irreversibly during the first charging process. This reduction behavior of P84 was systematically confirmed by cyclic voltammetry and Fourier-transform infrared analysis in attenuated total reflection mode of the Si anodes at differently charged voltages. The Si anode with P84 also shows ultrastable long-term cycle performance of 1313 mAh g(-1) after 300 cycles at 1.2 A g(-1) and 25 °C. From the morphological analysis on the basis of scanning electron microscopy and optical images and of the electrode adhesion properties determined by surface and interfacial cutting analysis system and peel tests, it was found that the P84 binder functions well and maintains the mechanical integrity of Si anodes during hundreds of cycles. As a result, when the loading level of the Si anode is increased from 0.2 to 0.6 mg cm(-2), which is a commercially acceptable level, the Si anode could deliver 647 mAh g(-1) until the 300th cycle, which is still two times higher than the theoretical capacity of graphite at 372 mAh g(-1).

18.
Biomed Res Int ; 2015: 723682, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25650308

RESUMO

BACKGROUND: DNA methyltransferase 3A (DNMT3A) mutation was recently introduced as a prognostic indicator in normal karyotype (NK) AML and we evaluated the incidence and prognostic impact of DNMT3A mutations in Korean NK AML patients. METHODS: Total 67 NK AML patients diagnosed during the recent 10 years were enrolled. DNMT3A mutations were analyzed by direct sequencing and categorized into nonsynonymous variations (NSV), deleterious mutations (DM), and R882 mutation based on in silico analysis results. Clinical features and prognosis were compared with respect to DNMT3A mutation status. RESULTS: Three novel (I158M, K219V, and E177V) and two known (R736H and R882H) NSVs were identified and the latter three were predicted as DMs. DNMT3A NSVs, DMs, and R882 mutation were identified in 14.9%-17.9%, 10.3%-10.4%, and 7.5% of patients, respectively. DNMT3A mutations were frequently detected in FLT3 ITD mutated patients (P=0.054, 0.071, and 0.071 in NSV, DMs, and R882 mutation, resp.) but did not affect clinical features and prognosis significantly. CONCLUSIONS: Incidences of DNMT3A NSVs, DMs, and R882 mutation are 14.9%-17.9%, 10.3%-10.4%, and 7.5%, respectively, in Korean NK AML patients. DNMT3A mutations are associated with FLT3 ITD mutations but do not affect clinical outcome significantly in Korean NK AML patients.


Assuntos
Povo Asiático/genética , DNA (Citosina-5-)-Metiltransferases/genética , Leucemia Mieloide Aguda/epidemiologia , Leucemia Mieloide Aguda/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/estatística & dados numéricos , Sequência de Bases , Criança , Estudos de Coortes , DNA Metiltransferase 3A , Análise Mutacional de DNA , Feminino , Humanos , Incidência , Cariótipo , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Análise Multivariada , Prognóstico , República da Coreia/epidemiologia , Análise de Sobrevida , Adulto Jovem
19.
ACS Appl Mater Interfaces ; 6(1): 526-31, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24321010

RESUMO

The adhesion strength of lithium-ion battery (LIB) electrodes consisting of active material, a nanosized electric conductor, and a polymeric binder is measured with a new analysis tool, called the Surface and Interfacial Cutting Analysis System (SAICAS). Compared to the conventional peel test with the same electrode, SAICAS gives higher adhesion strength owing to its elaborate cutting-based measurement system. In addition, the effects on the adhesion property of the polymeric binder type and content, electrode density, and measuring point are also investigated to determine whether SAICAS provides reliable results. The findings confirm SAICAS as an effective and promising tool to measure and analyze the adhesion properties of LIB electrodes.

20.
ACS Appl Mater Interfaces ; 5(22): 12005-10, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24195666

RESUMO

Mesoporous silicon nanofibers (m-SiNFs) have been fabricated using a simple and scalable method via electrospinning and reduction with magnesium. The prepared m-SiNFs have a unique structure in which clusters of the primary Si nanoparticles interconnect to form a secondary three-dimensional mesoporous structure. Although only a few nanosized primary Si particles lead to faster electronic and Li(+) ion diffusion compared to tens of nanosized Si, the secondary nanofiber structure (a few micrometers in length) results in the uniform distribution of the nanoparticles, allowing for the easy fabrication of electrodes. Moreover, these m-SiNFs exhibit impressive electrochemical characteristics when used as the anode materials in lithium ion batteries (LIBs). These include a high reversible capacity of 2846.7 mAh g(-1) at a current density of 0.1 A g(-1), a stable capacity retention of 89.4% at a 1 C rate (2 A g(-1)) for 100 cycles, and a rate capability of 1214.0 mAh g(-1) (at 18 C rate for a discharge time of ∼3 min).

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