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1.
J Mol Model ; 30(9): 305, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39134902

RESUMO

CONTEXT: Li2VMgO6, Li2NbMgO6, and Li2TaMgO6 double perovskite compounds were energetically the most stable in the FM phase. The lattice constants were 7.63 Å, 7.94 Å, and 7.95 Å, and the Curie temperatures were 910.451 K, 930.739 K, and 1258.821 K, respectively. The wide bandgap semiconductor characters were provided in the GGA-PBE methods as 2.139 eV, 4.209 eV, and 5.007 eV, respectively. This wide band gap semiconductor state in the majority carriers and the metallic state in the minority states made these double perovskites true half-metallic ferromagnetics. The bulk modulus obtained in the ground state calculations and the values obtained from thermodynamic calculations were relatively close. Debye temperatures in the initial state conditions were 747 K, 685.13 K, and 587.77 K, respectively. The total magnetic moment values were calculated as 3.00 µB/f.u. The most significant contribution to this value came from oxygen atoms. METHODS: The theoretical calculations of Li2VMgO6, Li2NbMgO6, and Li2TaMgO6 double perovskite alloys were performed using the WIEN2k program developed by Blaha et al. The electronic calculations were made with GGA-PBE, GGA + mBJ, and GGA + U approximations in the space number 225 and the Fm-3 m symmetry group. The thermodynamic calculations were performed using Gibbs2. In thermodynamic calculations, temperature increases were determined as 100 K and temperature values were increased from 0 to 1200 K.

2.
Sci Rep ; 14(1): 9237, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649420

RESUMO

In this work, the full-potential linearized augmented plane wave method (FP- LAPW) and the modified Becke-Johnson (mBJ) functional with spin-orbit (SO) coupling are used the obtain the structural, optoelectronic and thermoelectric properties of Tl2O3 under pressure. The results show that Tl2O3, as transparent conducting oxide (TCO), is a direct bandgap semiconductor with a band gap of 1.23 eV. The band gap value and the effective mass of electrons increases by increasing pressure. Density of state spectra reveal that the nature of electrons in Tl-6s state in the bottom of conduction band, like free electrons in s state, is responsible for the conducting behavior of Tl2O3. A blue shift is observed in optical spectra such as electron energy loss and absorption spectra with an increase in pressure. Obtained dielectric constants under pressure are inversely proportional to the band gap value according to Penn model. The effects of pressure on thermometric properties are also explored. The hydrostatic pressure increases Seebeck coefficient, while it decreases thermal conductivity that is an effective way to the enhancement of the thermoelectric efficiency of TCOs. A figure of merit (ZT) of 0.98 in p-type Tl2O3 is achieved that is desirable for using in thermoelectric devices.

3.
Ann Hematol ; 99(2): 301-307, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31844933

RESUMO

Classical Hodgkin lymphoma (cHL) is considered a curable disease; however, approximately one-third of responders experience disease relapse following first-line therapy. Several studies have shown the efficacy of brentuximab vedotin (BV) in patients with relapsed/refractory HL. We present a retrospective analysis of 58 patients with relapsed/refractory HL treated with BV in a named patient program from 11 centers. The median follow-up duration was 20 (range, 4-84) months. The best overall response rate was 64% (complete response [CR], 31%; partial response [PR], 33%). The 5-year progression-free survival (PFS) and overall survival (OS) rates were 12% (95% confidence interval [CI], 0.05-0.22) and 26% (95% CI, 0.16-0.38), respectively. Among patients who achieved CR, the estimated 5-year PFS and OS rates were 32% (95% CI, 0.13-0.54) and 60% (95% CI, 0.33-0.78), respectively. A total of 26 patients underwent subsequent stem cell transplantation. The 5-year PFS and OS rates for 10 patients who had consolidative stem cell transplantation were 28% and 30%, respectively. Twenty-seven patients required further therapy following BV. At the time of the analysis, 12 patients (21%) were alive. Five patients (9%) had long-term remission after achieving CR with BV monotherapy, with a median PFS of 76 months. Three of them (5%) did not receive any other treatment following BV and their median PFS was 75 months. Our long-term results showed that a small subset of patients with relapsed/refractory cHL may benefit from and even be cured with BV monotherapy.


Assuntos
Brentuximab Vedotin/administração & dosagem , Doença de Hodgkin , Transplante de Células-Tronco , Adulto , Aloenxertos , Autoenxertos , Brentuximab Vedotin/efeitos adversos , Intervalo Livre de Doença , Feminino , Seguimentos , Doença de Hodgkin/mortalidade , Doença de Hodgkin/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida
4.
Turk J Haematol ; 37(2): 84-90, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31630512

RESUMO

Objective: Chronic antigenic stimulation is frequently blamed in the pathogenesis of extranodal marginal zone lymphomas including splenic marginal zone lymphoma (SMZL). Chronic hepatitis C is frequently observed in SMZL patients in some geographical regions. However, these reports are largely from North America and Europe, and data from other countries are insufficient. In this multicenter study we aimed to identify the clinical characteristics of SMZL patients in Turkey, including viral hepatitis status and treatment details. Materials and Methods: Data were gathered from participating centers from different regions of Turkey using IBM SPSS Statistics 23 for Windows. Hepatitis B virus surface antigen (HBsAg), anti-HBs antibody, anti-HB core antigen antibody (anti-HBcAg), HB viral load, anti-hepatitis C virus (HCV) antibody, HCV viral load results were analyzed. Results: One hundred and four patients were reported. Hepatitis C virus positivity was observed in only one patient. However, hepatitis B virus surface antigen (HBsAg) positivity was observed in 11.2% and HBsAg and/or anti-HB core antigen antibody (anti-HBcAg) positivities were seen in 34.2% of the patients. The median age was 60 years (range=35-87). Median follow-up duration was 21.2 months (range=00.2-212; 23.2 months for surviving patients). Median overall survival was not reached. Estimated 3-year and 10-year survival rates were 84.8% and 68.9%, respectively. Older age, no splenectomy during follow-up, platelet count of <90x103/µL, lower albumin, higher lactate dehydrogenase, higher ß2-microglobulin, and HBsAg positivity were associated with increased risk of death. Only albumin remained significant in multivariable analysis. Conclusion: These results indicate that hepatitis B virus may be a possible risk factor for SMZL in our population. It may also be an indirect prognostic factor.


Assuntos
Hepatite B/complicações , Linfoma de Zona Marginal Tipo Células B/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Turquia
7.
Clin Lymphoma Myeloma Leuk ; 16(5): 269-74, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26927932

RESUMO

BACKGROUND: The prognosis of Philadelphia-positive acute lymphoblastic leukemia (Ph(+) ALL) is generally poor. Currently, allogeneic hematopoietic cell transplantation (allo-HCT) is the only accepted therapy with curative potential. PATIENTS AND METHODS: Herein, we report our multicenter, retrospective experience with 46 (23 female; 23 male) Ph(+) ALL patients, who were treated off-study between 2005 and 2012. RESULTS: The median age of the patients was 46 years (range, 19-73 years). During induction, 30 (65%), 13 (28%), and 3 (7%) patients received tyrosine kinase inhibitors (TKIs) concurrent with chemotherapy (TKIs/chemotherapy), chemotherapy only, and TKIs only, respectively. Following induction, rates of complete remission (CR) of the study population were 85% (n = 39). CR rate in patients receiving TKIs during induction (n = 33) was significantly higher compared with patients who received chemotherapy only (n = 13; P = .011). Taking TKIs during induction significantly reduced induction mortality (3.3% vs. 38%; P = .01). Allo-HCT was performed subsequently in 21 (46%) patients. More patients who received TKIs with or without chemotherapy (19/33; 58%) during induction were able to undergo to allo-HCT compared with patients who received chemotherapy only (2/13; 15%; P = .005). Median overall survival of patients who were treated with TKIs during induction and received allo-HCT (not reached; NR) was significantly prolonged compared with patients who received allo-HCT but without TKIs during induction (23.2 months) and to the rest of the cohort (21.2 months; P = .019). CONCLUSIONS: Current state-of-the art management of Ph(+) ALL in real-life seems to be incorporation of TKIs to chemotherapy regimens and proceeding to allo-HCT, whenever possible.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Gerenciamento Clínico , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
Transfus Apher Sci ; 49(3): 590-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23981652

RESUMO

Due to the high transplant related morbidity and mortality (TRM), relatively younger acute leukemia patients that have a good performance status and no comorbidity are eligible for myeloablative conditioning (MAC) followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT). The outcomes of 84 consecutive adult patients with ALL (n=38) or AML (n=46) who underwent allo-HSCT from their HLA-identical siblings were evaluated retrospectively. The median age at transplantation was 34 (17-58 years) for the whole patient population. Of these, 24 patients received a MAC and 60 patients received a fludarabine-based reduced intensity conditioning regimen (RIC). After a median follow-up of 32 months (range, 1-119), for the entire group, the 3-year estimated overall survival (OS) was 57.5% and the disease-free survival (DFS) was 51.5%. The OS for ALL and AML patients were 53.9% vs 62.1%: and DFS were 50.5% and 53.4%, respectively. The 3-year estimated OS for RIC and MAC patients were 63.2% and 41.7%; and DFS were 57.1% and 34.7%, respectively. In ALL patients, conditioning regimens (RIC vs MAC) led to similar OS and DFS; however, in AML patients both OS (70.1% vs 21.4%) and DFS (59.3% vs 42.9%) were found to be higher in RIC patients compared to MAC recipients. Overall, the TRM at day 100 was 1.7% and has increased up to 5.1% at 1st year. In multivariate analysis, the diagnosis (p=0.03) and RIC regimen (p=0.027) were the prognostic variables for prolonged OS in all patients; and RIC regimen (p=0.031) was the only prognostic factor for prolonged OS in AML patients. The first complete remission (CR1) was correlated with a prolonged DFS as an independent variable for all patients (p=0.09). Eleven of the RIC patients (18.3%) and 6 of the MAC patients (25%) developed acute graft-versus-host disease (GvHD). Seventeen of the RIC patients (33.3%) and 4 of the MAC patients (16.7%) developed chronic GvHD. In conclusion, RIC conditioning regimens may provide a longer OS and DFS, especially in patients with AML who are in first CR, not eligible for MAC conditioning.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/cirurgia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirurgia , Condicionamento Pré-Transplante/métodos , Doença Aguda , Adolescente , Adulto , Feminino , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Irmãos , Doadores de Tecidos , Condicionamento Pré-Transplante/efeitos adversos , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
9.
Acta Haematol ; 130(3): 199-205, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23797290

RESUMO

Treatment of acute lymphoblastic leukemia is unsatisfactory in adults due to disease and patient-related factors and probably because adult chemotherapy regimens are weaker than pediatric protocols. Worries about inadequacy of adult regimens urged many hematologists, including us, to reconsider their routine treatment practices. In this retrospective multicenter study, we aimed to evaluate results of hyper-CVAD treatment in comparison to other intensive protocols. All patients aged ≤65 years who were commenced on intensive induction chemotherapy between 1999 and 2011 were included in the study. Sixty-eight of 166 patients received hyper-CVAD, 65 were treated with CALGB-8811 regimen and 33 with multiple other protocols. Limited number of patients who were treated with other intensive protocols and mature B-acute lymphoblastic leukemia cases who were mostly given hyper-CVAD were eliminated from the statistical analyses. In spite of a favorable complete remission rate (84.2%), overall (26.3 vs. 44.2% at 5 years, p = 0.05) and disease-free (24.9 vs. 48.2%, p = 0.001) survival rates were inferior with hyper-CVAD compared to CALGB-8811 due to higher cumulative nonrelapse mortality risk (29.7 vs. 5.9%, p = 0.003) and no superiority in cumulative relapse incidence comparison (45% for both arms, p = 0.44). Hyper-CVAD, in its original form, was a less favorable regimen in our practice.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Vincristina/administração & dosagem , Vincristina/efeitos adversos
10.
Turk J Haematol ; 30(2): 188-90, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24385784

RESUMO

UNLABELLED: The incidence of deep vein thrombosis (DVT) after non-myeloablative (NMA) allogeneic stem cell transplantation (allo-SCT) is unknown. In addition, very few studies on the predisposing factors for DVT post SCT have been published. The incidence of DVT among patients that underwent NMA allo-SCT at our hospital was 4.1% (3 of 73) over the course of last 8 years, and to the best of our knowledge this is the first study to report the incidence of DVT following NMA allo-SCT. The present findings show that NMA allo-SCT patients may have multiple risk factors for DVT. Herein we present 3 cases of DVT following NMA allo-SCT and a literature review. CONFLICT OF INTEREST: None declared.

11.
Cytokine ; 61(2): 572-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23159284

RESUMO

Granulocyte-colony stimulating factor (G-CSF) has become the most effective agent supporting hematopoietic stem cell transplantation (HSCT). The cognate interaction between G-CSF and its specific receptor, G-CSFR, induces the mobilization of HSCs and increases their pool in the peripheral blood. G-CSFR has a highly conserved structure which may be functionally modulated by the presence of missense single nucleotide polymorphisms (SNPs). In this study, we asked whether the missense SNPs in G-CSFR could affect the response to G-CSF in HSCT patients and donors. Here, for the first time, G-CSFR missense SNPs were screened and minor allele frequencies were determined in a specific population with Turkish racial background. Five (rs3917991, rs3918001, rs3918018, rs3918019, and rs146617729) out of 16 missense SNPs screened were determined with minor allele frequencies lower than 0.04. Subsequent association analyses indicated potential impact of rs3918001, rs3918018, and rs3918019 minor alleles on peripheral blood CD34(+) cell enrichment. Although their frequency is rather low, certain missense SNPs, especially which are placed in the conserved regions of G-CSFR may possess the capacity to influence the response to G-CSF treatment.


Assuntos
Células-Tronco Hematopoéticas/citologia , Polimorfismo de Nucleotídeo Único/genética , Receptores de Fator Estimulador de Colônias/genética , Adulto , Antígenos CD34/metabolismo , Feminino , Frequência do Gene/genética , Haplótipos/genética , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade
13.
World J Gastroenterol ; 17(27): 3220-8, 2011 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-21912471

RESUMO

AIM: To investigate the expression levels of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), vascular endothelial growth factor receptor-3 (VEGFR-3) and CD44 genes and the relationship between their levels and clinicopathological parameters in gastric cancer. METHODS: Tissue samples were obtained from 33 patients (8 females) with gastric cancer. mRNA levels of LYVE-1, VEGFR-3 and CD44 in normal and tumor tissues were quantitatively measured using real time polymerase chain reaction. The results were correlated with lymph node metastasis, histological type and differentiation of the tumor, T-stage, and presence of vascular, perineural and lymphatic invasions. The distribution of molecules in the tissue was evaluated using immunohistochemistry. RESULTS: LYVE-1, CD44 and VEGFR-3 gene expression levels were significantly higher in gastric cancer than in normal tissue. While there was no correlation between gene expressions and clinicopathologic features such as histologic type, differentiation and stage, gene expression levels were found to be increased in conjunction with positive lymph node/total lymph node ratio and the presence of perineural invasion. A significant correlation was also found between LYVE-1 and CD44 over-expressions and perineural invasion and lymph node positivity in gastric cancers. When the distribution of LYVE-1 antibody-stained lymphatic vessels in tissue was evaluated, lymphatic vessels were located intra-tumorally in 13% and peri-tumorally in 27% of the patients. Moreover, lymph node metastases were also positive in all patients with LYVE-1-staining. CONCLUSION: LYVE-1, VEGFR-3 and CD44 all play an important role in lymphangiogenesis, invasion and metastasis. LYVE-1 is a perfectly reliable lymphatic vessel marker and useful for immunohistochemistry.


Assuntos
Regulação Neoplásica da Expressão Gênica , Receptores de Hialuronatos/biossíntese , Neoplasias Gástricas/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Proteínas de Transporte Vesicular/biossíntese , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica/métodos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/metabolismo
19.
Clin Transplant ; 23(6): 981-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19689453

RESUMO

We present a rare experience with a myeloma patient who had a late relapse as isolated extramedullary plasmacytoma of the thyroid gland after a second allogeneic transplantation. We give PET/CT scan findings at diagnosis and during follow up of the disease after subsequent management. The possible pathogenesis of the late extramedullary relapse of myeloma after allogeneic stem-cell transplantation and management options are discussed.


Assuntos
Cadeias kappa de Imunoglobulina/metabolismo , Mieloma Múltiplo/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Plasmocitoma/diagnóstico , Transplante de Células-Tronco/efeitos adversos , Neoplasias da Glândula Tireoide/diagnóstico , Biópsia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/cirurgia , Recidiva Local de Neoplasia/metabolismo , Plasmocitoma/metabolismo , Plasmocitoma/cirurgia , Tomografia por Emissão de Pósitrons , Prognóstico , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/cirurgia , Fatores de Tempo , Transplante Homólogo
20.
Clin Transplant ; 23(6): 839-47, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20447186

RESUMO

Autologous stem-cell transplantation (ASCT) has emerged as the standard approach in patients with multiple myeloma, although it is unlikely to achieve cure. Thalidomide maintenance and non-myeloablative allogeneic transplantation (NST) may increase complete remission (CR) rate and increase overall survival. In this study, 35 ASCT and 10 NST were performed in 33 patients. Patients, who were resistant or relapsed following ASCT, underwent NST if they had an HLA-matched sibling, otherwise treated with a second ASCT. Thalidomide was started as maintenance after ASCT. After first transplantation, three patients underwent second ASCT and 10 patients underwent NST. Following first transplantation, CR rate was 39% and increased to 60% (overall response 93%) with addition of thalidomide, bortezomib, and second transplantation. CR was durable in 14 (42%) patients. During a median follow-up of 24 months, 18 patients progressed and nine patients died. The 100-d transplant-related mortality was <5%. The four-yr progression-free survival (PFS) was 52.4%. In conclusion, ASCT followed by thalidomide and NST in resistant patients can lead to high CR and PFS rates. As a second transplantation has not been performed routinely, patients having durable CR had a chance to avoid or delay a second transplantation without compromising disease control.


Assuntos
Mieloma Múltiplo/cirurgia , Indução de Remissão , Transplante de Células-Tronco/métodos , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Ácidos Borônicos/administração & dosagem , Ácidos Borônicos/uso terapêutico , Bortezomib , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Pirazinas/administração & dosagem , Pirazinas/uso terapêutico , Taxa de Sobrevida/tendências , Talidomida/administração & dosagem , Talidomida/uso terapêutico , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento
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