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1.
ACS Appl Mater Interfaces ; 15(51): 59358-59369, 2023 Dec 27.
Article de Anglais | MEDLINE | ID: mdl-38103256

RÉSUMÉ

Hydrogen fuel cells based on proton exchange membrane fuel cell (PEMFC) technology are promising as a source of clean energy to power a decarbonized future. However, PEMFCs are limited by a number of major inefficiencies; one of the most significant is hydrogen crossover. In this work, we comprehensively study the effects of two-dimensional (2D) materials applied to the anode side of the membrane as H2 barrier coatings on Nafion to reduce crossover effects on hydrogen fuel cells, while studying adverse effects on conductivity and catalyst performance in the beginning of life testing. The barrier layers studied include graphene, hexagonal boron nitride (hBN), amorphous boron nitride (aBN), and varying thicknesses of molybdenum disulfide (MoS2), all chosen due to their expected stability in a fuel cell environment. Crossover mitigation in the materials studied ranges from 4.4% (1 nm MoS2) to 46.1% (graphene) as compared to Nafion 211. Effects on proton conductivity are also studied, suggesting high areal proton transport in materials previously thought to be effectively nonconductive, such as 2 nm MoS2 and amorphous boron nitride under the conditions studied. The results indicate that a number of 2D materials are able to improve crossover effects, with those coated with 8 nm MoS2 and 1 L graphene able to achieve greater crossover reduction while minimizing conductivity penalty.

2.
Ther Adv Hematol ; 14: 20406207231205637, 2023.
Article de Anglais | MEDLINE | ID: mdl-37929079

RÉSUMÉ

Background: Droplet digital polymerase chain reaction (ddPCR) is an exact method of measurement. Objectives: We conducted this study to identify the prognostic factors for successful treatment-free remission in patients with chronic-phase chronic myeloid leukemia who discontinued tyrosine kinase inhibitors (TKIs). We also aimed to validate ddPCR for predicting molecular relapse. Design: This is a prospective, multicenter study. Methods: We enrolled patients treated with TKIs for at least 3 years with a confirmed sustained deep molecular response (DMR) for at least 1 year. TKI was re-administered in patients who experienced the loss of major molecular response (MMR). Results: A total of 66 patients from five institutions in South Korea were enrolled. During a median follow-up period of 16.5 months, 29/66 (43.9%) patients experienced molecular relapse; the probability of molecular relapse-free survival (RFS) at 6 or 12 months after TKI discontinuation was 65.6% or 57.8%, respectively, with most molecular relapses occurring within the first 7 months. All patients who lost MMR were re-treated with TKI, and all re-achieved MMR at a median of 2.8 months. E14a2 transcript type (p = 0.005) and longer DMR duration (⩾48 months) prior to TKI discontinuation (p = 0.002) were associated with prolonged molecular RFS and with sustained DMR. Patients with both e13a2 transcript type and detectable BCR::ABL1 (⩾MR5.0) by ddPCR at the time of TKI discontinuation showed shorter duration of molecular RFS (p = 0.015). Conclusion: Our data suggest that transcript type and BCR::ABL1 transcript levels on ddPCR should be taken into consideration when deciding whether to discontinue TKI therapy.

3.
Adv Mater ; 35(43): e2205520, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-36539122

RÉSUMÉ

With advances in flexible electronics, innovative foldable, rollable, and stretchable displays have been developed to maintain their performance under various deformations. These flexible devices can develop more innovative designs than conventional devices due to their light weight, high space efficiency, and practical convenience. However, developing flexible devices requires material innovation because the devices must be flexible and exhibit desirable electrical insulating/semiconducting/metallic properties. Recently, emerging 2D materials such as graphene, hexagonal boron nitride, and transition metal dichalcogenides have attracted considerable research attention because of their outstanding electrical, optical, and mechanical properties, which are ideal for flexible electronics. The recent progress and challenges of 2D material growth and display applications are reviewed and perspectives for exploring 2D materials for display applications are discussed.

4.
Leuk Res ; 114: 106791, 2022 03.
Article de Anglais | MEDLINE | ID: mdl-35101736

RÉSUMÉ

Genetic differences may be associated with the response to tyrosine kinase inhibitor (TKI) in patients with chronic myeloid leukemia (CML). In this study, we identified genetic alterations between rapid and slow responders (BCR/ABL1 International Scale at 6 months: ≤0.1 % vs. > 0.1 %) of TKI treatment in chronic phase CML patients. Our analyses involved single nucleotide polymorphism (SNP), a Genome Wide Association Study and a Network-wide Association Study (NetWAS). Seventy-two patients from 16 institutions were enrolled and treated with a TKI, nilotinib. Gene Set Analysis identified genetic alterations in pathways related to the differentiation, proliferation, and activity of various innate immune cells. The NetWAS analysis found that genes associated with natural killer (NK) cells (PTPRCAP, BLNK, HCK, ARHGEF11, GPR183, TRPV2, SHKBP1, CD2) showed significant differences between rapid and slow responders of nilotinib. However, we found no significantly different genetic alterations according to the response in the SNP analysis. In conclusion, we found that rapidity of response to TKI was associated with pathway-associated genetic alterations in immune cells, particularly with respect to NK cell activity. These results suggested that the innate immune system at initial diagnosis had an important role in treatment response in patients with CML.


Sujet(s)
Étude d'association pangénomique , Leucémie myéloïde chronique BCR-ABL positive , Protéines de fusion bcr-abl/génétique , Humains , Cellules tueuses naturelles/métabolisme , Leucémie myéloïde chronique BCR-ABL positive/diagnostic , Leucémie myéloïde chronique BCR-ABL positive/traitement médicamenteux , Leucémie myéloïde chronique BCR-ABL positive/génétique , Mutation , Inhibiteurs de protéines kinases/pharmacologie , Inhibiteurs de protéines kinases/usage thérapeutique
5.
Blood Res ; 57(1): 13-19, 2022 Mar 31.
Article de Anglais | MEDLINE | ID: mdl-35197370

RÉSUMÉ

The mutational and epigenetic landscape of acute myeloid leukemia (AML) has become increasingly well understood in recent years, informing on biological targets for precision medicine. Among the most notable findings was the recognition of mutational hot-spots in the isocitrate dehydrogenase (IDH) genes. In this review, we provide an overview on the IDH1/2 mutation landscape in Korean AML patients, and compare it with available public data. We also discuss the role of IDH1/2 mutations as biomarkers and drug targets. Taken together, occurrence of IDH1/2 mutations is becoming increasingly important in AML treatment, thus requiring thorough examination and follow-up throughout the clinical course of the disease.

6.
Leuk Res ; 111: 106728, 2021 12.
Article de Anglais | MEDLINE | ID: mdl-34673444

RÉSUMÉ

Ultra-deep sequencing detects low-frequency genetic mutations with high sensitivity. We used this approach to prospectively examine mutations in the BCR/ABL1 tyrosine kinase from patients with newly diagnosed, chronic-phase chronic myeloid leukemia (CML) treated with the tyrosine kinase inhibitor nilotinib. Between May 2013 and November 2014, 50 patients from 18 institutions were enrolled in the study. We screened 103 somatic mutations and found that mutations in the P-loop domain were the most frequent (173/454 mutations in the P-loop) and noted the presence of the V299 L mutation (dasatinib-resistant/nilotinib-sensitive) in 98 % of patients (49/50). No patients had Y253H, E255 V, or F359 V/C/I mutations, which would recommend dasatinib rather than nilotinib treatment. The S417Y mutation was associated with lower achievement of a major molecular response (MMR) at 6 months, and the V371A mutation was associated with reduced MMR and MR4.5 durations (MMR for 2 years: 100 % for no mutation vs. 75 % for mutation, P=0.039; MR4.5 for 15 months: 94.1 % vs. 25 %, P=0.002). Patients with known nilotinib-resistant mutations had lower rates of MR4.5 achievement. In conclusion, ultra-deep sequencing is a sensitive method for genetic-based treatment decisions. Based on the results of these mutational analyses, nilotinib treatment is a promising option for Korean patients with CML.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Marqueurs biologiques tumoraux/génétique , Résistance aux médicaments antinéoplasiques/génétique , Protéines de fusion bcr-abl/génétique , Leucémie myéloïde chronique BCR-ABL positive/anatomopathologie , Mutation , Dasatinib/administration et posologie , Femelle , Études de suivi , Séquençage nucléotidique à haut débit , Humains , Leucémie myéloïde chronique BCR-ABL positive/traitement médicamenteux , Leucémie myéloïde chronique BCR-ABL positive/génétique , Mâle , Adulte d'âge moyen , Pronostic , Études prospectives , Pyrimidines/administration et posologie , Taux de survie
7.
JMIR Med Inform ; 9(6): e26230, 2021 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-34096877

RÉSUMÉ

BACKGROUND: The Health Avatar Platform provides a mobile health environment with interconnected patient Avatars, physician apps, and intelligent agents (termed IoA3) for data privacy and participatory medicine; however, its fully decentralized architecture has come at the expense of decentralized data management and data provenance. OBJECTIVE: The introduction of blockchain and smart contract technologies to the legacy Health Avatar Platform with a clinical metadata registry remarkably strengthens decentralized health data integrity and immutable transaction traceability at the corresponding data-element level in a privacy-preserving fashion. A crypto-economy ecosystem was built to facilitate secure and traceable exchanges of sensitive health data. METHODS: The Health Avatar Platform decentralizes patient data in appropriate locations (ie, on patients' smartphones and on physicians' smart devices). We implemented an Ethereum-based hash chain for all transactions and smart contract-based processes to guarantee decentralized data integrity and to generate block data containing transaction metadata on-chain. Parameters of all types of data communications were enumerated and incorporated into 3 smart contracts, in this case, a health data transaction manager, a transaction status manager, and an application programming interface transaction manager. The actual decentralized health data are managed in an off-chain manner on appropriate smart devices and authenticated by hashed metadata on-chain. RESULTS: Metadata of each data transaction are captured in a Health Avatar Platform blockchain node by the smart contracts. We provide workflow diagrams each of the 3 use cases of data push (from a physician app or an intelligent agents to a patient Avatar), data pull (request to a patient Avatar by other entities), and data backup transactions. Each transaction can be finely managed at the corresponding data-element level rather than at the resource or document levels. Hash-chained metadata support data element-level verification of data integrity in subsequent transactions. Smart contracts can incentivize transactions for data sharing and intelligent digital health care services. CONCLUSIONS: Health Avatar Platform and interconnected patient Avatars, physician apps, and intelligent agents provide a decentralized blockchain ecosystem for health data that enables trusted and finely tuned data sharing and facilitates health value-creating transactions with smart contracts.

8.
In Vivo ; 33(6): 2273-2280, 2019.
Article de Anglais | MEDLINE | ID: mdl-31662567

RÉSUMÉ

BACKGROUND/AIM: Droplet digital polymerase chain reaction (ddPCR) is an exact method of measuring nucleic acids. The aim of this prospective study was to evaluate minimal residual disease (MRD) using ddPCR in chronic myeloid leukemia (CML) patients. PATIENTS AND METHODS: Between May 2013 and November 2014, CML patients treated with nilotinib were enrolled in our study. BCR/ABL1 transcripts levels were evaluated using ddPCR at the first time of complete molecular response (CMR). We enrolled 15 patients from 7 Institutions. The treatment period and median follow-up period were 45 months and 47 months, respectively. RESULTS: Patients with a high level of BCR/ABL1 transcript had a greater tendency to lose the CMR during the follow-up period (p=0.095). In addition, patients with a low level of BCR/ABL1 transcript showed a longer duration of CMR compared to those with a high level (p=0.032). CONCLUSION: We found that ddPCR is a sensitive method for detecting MRD and that MRD could affect the duration of the treatment response.


Sujet(s)
Marqueurs biologiques tumoraux , ADN tumoral , Maladie résiduelle/diagnostic , Réaction de polymérisation en chaîne , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Association thérapeutique , Femelle , Études de suivi , Protéines de fusion bcr-abl/génétique , Humains , Leucémie myéloïde chronique BCR-ABL positive/diagnostic , Leucémie myéloïde chronique BCR-ABL positive/génétique , Leucémie myéloïde chronique BCR-ABL positive/mortalité , Leucémie myéloïde chronique BCR-ABL positive/thérapie , Mâle , Adulte d'âge moyen , Maladie résiduelle/génétique , Maladie résiduelle/mortalité , Réaction de polymérisation en chaîne/méthodes , Pronostic
9.
Cancer Med ; 7(5): 1814-1823, 2018 05.
Article de Anglais | MEDLINE | ID: mdl-29577674

RÉSUMÉ

Although nilotinib has improved efficacy compared to imatinib, suboptimal response and intolerable adverse events (AEs) limit its effectiveness in many patients with chronic myeloid leukemia in chronic phase (CML-CP). We investigated the 2-year efficacy and safety of nilotinib and their relationships with plasma nilotinib concentrations (PNCs). In this open-label, multi-institutional phase 4 study, 110 Philadelphia chromosome-positive CML-CP patients were treated with nilotinib at a starting dose of 300 mg twice daily. Molecular responses (MRs) and AEs were monitored for up to 24 months. The 24-month cumulative MR4.5 rate was evaluated as the primary endpoint. Plasma samples were collected from 94 patients to determine PNCs, and the per-patient mean was used to categorize them into four mean PNC (MPNC) groups. Cumulative MR rates and safety were compared between groups. With a median follow-up of 22.2 months, the 24-month cumulative MR4.5 rate was 56.2% (95% confidence interval, 44.0%-8.3%), and the median time to MR4.5 was 23.3 months. There were no significant differences in the cumulative rates of major molecular response, MR4 , and MR4.5 between MPNC groups. One patient died due to acute viral hepatitis, and two developed hematological or cytogenetic relapse, while no progression to accelerated or blast phase was observed. Safety results were consistent with previous studies with no new safety signal identified. Across the MPNC groups, there was no significant linear trend in the frequency of AEs. Nilotinib is highly effective for the treatment of CML-CP with manageable AEs. The measurement of PNC has no predictive value for patient outcomes and is thus not found to be clinically useful. This study is registered with clinicaltrials.gov, Number NCT03332511.


Sujet(s)
Leucémie myéloïde chronique BCR-ABL positive/traitement médicamenteux , Pyrimidines/administration et posologie , Pyrimidines/pharmacocinétique , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Chromatographie en phase liquide , Calendrier d'administration des médicaments , Femelle , Humains , Mâle , Adulte d'âge moyen , Pyrimidines/effets indésirables , République de Corée , Spectrométrie de masse en tandem , Résultat thérapeutique
10.
Int J Hematol ; 100(2): 141-51, 2014 Aug.
Article de Anglais | MEDLINE | ID: mdl-24996615

RÉSUMÉ

The present study sought to elucidate the role of induction and consolidation therapy in elderly patients. We retrospectively collected data of 477 patients who were aged over 60 years at the time of acute myeloid leukemia (AML) diagnosis. The median overall survival (OS) was 339 days in the induction group (n = 266) and 86 days in the best supportive care group (n = 211) (P < 0.001). In the induction group, the complete remission (CR) rate was 58.3 %, and treatment-related death was 15.4 %. Successful induction was related to good performance [Eastern Cooperative Oncology Group (ECOG <2)] [hazard ratio (HR) 3.215; P = 0.002]. Mortality correlated with failure to achieve CR (HR 4.059; P < 0.001) and poor performance status (ECOG >2) (HR 2.731; P = 0.035). In CR patients, poor karyotype and absence of consolidation (HR 2.313; P = 0.003) correlated with mortality. More than one cycle of consolidation was associated with better OS (P < 0.001). Lack of salvage therapy was associated with mortality in patients who did not achieve CR (HR 3.223; P = 0.005). Intensive induction in patients with good performance and >1 cycle of consolidation after CR may be the best strategy for improving OS in elderly AML patients.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique , Chimiothérapie de consolidation/méthodes , Leucémie aigüe myéloïde/traitement médicamenteux , Sujet âgé , Sujet âgé de 80 ans ou plus , Cytarabine/administration et posologie , Daunorubicine/administration et posologie , Femelle , Humains , Idarubicine/administration et posologie , Caryotypage , Leucémie aigüe myéloïde/mortalité , Leucémie aigüe myéloïde/anatomopathologie , Mâle , Adulte d'âge moyen , Induction de rémission , Études rétrospectives , Thérapie de rattrapage , Analyse de survie , Résultat thérapeutique , Vidarabine/administration et posologie , Vidarabine/analogues et dérivés
11.
ACS Appl Mater Interfaces ; 6(10): 7885-94, 2014 May 28.
Article de Anglais | MEDLINE | ID: mdl-24780393

RÉSUMÉ

The electrical properties of La-silicate films grown by atomic layer deposition (ALD) on Ge substrates with different film configurations, such as various Si concentrations, Al2O3 interfacial passivation layers, and SiO2 capping layers, were examined. La-silicate thin films were deposited using alternating injections of the La[N{Si(CH3)3}2]3 precursor with O3 as the La and O precursors, respectively, at a substrate temperature of 310 °C. The Si concentration in the La-silicate films was further controlled by adding ALD cycles of SiO2. For comparison, La2O3 films were also grown using [La((i)PrCp)3] and O3 as the La precursor and oxygen source, respectively, at the identical substrate temperature. The capacitance-voltage (C-V) hysteresis decreased with an increasing Si concentration in the La-silicate films, although the films showed a slight increase in the capacitance equivalent oxide thickness. The adoption of Al2O3 at the interface as a passivation layer resulted in lower C-V hysteresis and a low leakage current density. The C-V hysteresis voltages of the La-silicate films with Al2O3 passivation and SiO2 capping layers was significantly decreased to ∼0.1 V, whereas the single layer La-silicate film showed a hysteresis voltage as large as ∼1.0 V.

12.
Chonnam Med J ; 49(2): 75-80, 2013 Aug.
Article de Anglais | MEDLINE | ID: mdl-24010070

RÉSUMÉ

This study examined salivary flow and salivary pH and the prevalence and levels of cariogenic bacteria in the saliva of oncological patients and healthy controls. Quantitative real-time polymerase chain reaction was used to assess the levels of microbes including Streptococcus mutans, Streptococcus sobrinus, Lactobacillus salivarius, and Lactobacillus acidophilus in the saliva of 41 patients with a solid tumor (SO), 30 patients with a hematologic malignancy (HE), and 40 healthy controls. Salivary flow and pH were lower in oncological patients than in controls. The frequencies of all four cariogenic bacteria were highest in the SO group. S. mutans and L. salivarius were the most commonly detected in all three study groups. Mean numbers of S. sobrinus and L. salivarius in the SO group were significantly higher than in controls (p<0.05). There were no significant differences between patients and controls with respect to mean numbers of S. mutans and L. acidophilus in saliva. However, the proportions of S. mutans, S. sobrinus, and L. salivarius versus total bacteria in the SO group were significantly higher than in controls. Within patients, both mean numbers and the proportions of S. mutans and S. sobrinus were significantly different (p<0.05). In summary, significant differences were found in salivary pH values and the levels of S. mutans, S. sobrinus, and L. salivarius between SO patients and healthy controls.

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