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1.
Matter ; 4(3): 821-844, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35757372

RESUMO

Fabrication of anisotropic materials is highly desirable in designing biomaterials and tissue engineered constructs. Electrospinning has been broadly adopted due to its versatility in producing non-woven fibrous meshes with tunable fiber diameters (from 10 nanometers to 10 microns), microarchitectures, and construct geometries. A myriad of approaches have been utilized to control fiber alignment of electrospun materials to achieve complex microarchitectures, improve mechanical properties, and provide topographical cellular cues. This review provides a comparative analysis of the techniques developed to generate fiber alignment in electrospun materials. A description of the underlying mechanisms that drive fiber alignment, setup variations for each technique, and the resulting impact on the aligned microarchitecture is provided. A critical analysis of the advantages and limitations of each approach is provided to guide researchers in method selection. Finally, future perspectives of advanced electrospinning methodologies are discussed in terms of developing a scalable method with precise control of microarchitecture.

2.
Int J Biol Macromol ; 164: 4084-4094, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32890563

RESUMO

A facile and greener methodology to obtain pure chitosan-based 3D porous structures in the form of monoliths and films is proposed. It is based on a modified evaporation-induced phase separation process in a chitosan solution precursor. In this approach, a deep eutectic solvent (DES) is used as the nonsolvent system and an ecofriendly, cost effective, simple and versatile alternative for the production of highly structured chitosan materials. The porous heterogeneous structure can be fine-tuned by varying the chitosan content in the precursor solution and chitosan/DES ratio, and enabled the structured polymer to absorb large amounts of water to form hydrogels. This is a versatile and unexplored approach to design porous chitosan with tailored morphology in the absence of crosslinkers, which, based on preliminary studies on V. cholerae biofilm formation, is expected to open new avenues for various applications in biomedical, catalysis, water purification, filtration and other areas where the control of bacterial biofilm formation is critical.


Assuntos
Biopolímeros/química , Quitosana/química , Solventes/química , Fenômenos Químicos , Extração Líquido-Líquido , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
3.
J Hematol Oncol ; 11(1): 96, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-30041662

RESUMO

Recurrent deletions of the CDKN2A/ARF/CDKN2B genes encoded at chromosome 9p21 have been described in both pediatric and adult acute lymphoblastic leukemia (ALL), but their prognostic value remains controversial, with limited data on adult T-ALL. Here, we investigated the presence of homozygous and heterozygous deletions of the CDKN2A/ARF and CDKN2B genes in 64 adult T-ALL patients enrolled in two consecutive trials from the Spanish PETHEMA group. Alterations in CDKN2A/ARF/CDKN2B were detected in 35/64 patients (55%). Most of them consisted of 9p21 losses involving homozygous deletions of the CDKNA/ARF gene (26/64), as confirmed by single nucleotide polymorphism (SNP) arrays and interphase fluorescence in situ hybridization (iFISH). Deletions involving the CDKN2A/ARF/CDKN2B locus correlated with a higher frequency of cortical T cell phenotype and a better clearance of minimal residual disease (MRD) after induction therapy. Moreover, the combination of an altered copy-number-value (CNV) involving the CDKN2A/ARF/CDKN2B gene locus and undetectable MRD (≤ 0.01%) values allowed the identification of a subset of T-ALL with better overall survival in the absence of hematopoietic stem cell transplantation.


Assuntos
Inibidor de Quinase Dependente de Ciclina p15/genética , Deleção de Genes , Genes p16 , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteína Supressora de Tumor p14ARF/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Prognóstico
4.
Leukemia ; 32(1): 21-29, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28584252

RESUMO

Treatment outcome in older patients with acute promyelocytic leukemia (APL) is lower compared with younger patients, mainly because of a higher induction death rate and postremission non-relapse mortality (NRM). This prompted us to design a risk- and age-adapted protocol (Programa Español de Tratamientos en Hematología (PETHEMA)/HOVON LPA2005), with dose reduction of consolidation chemotherapy. Patients aged ⩾60 years reported to the PETHEMA registry and were treated with all-trans retinoic acid (ATRA) plus anthracycline-based regimens according to three consecutive PETHEMA trials that were included. We compared the long-term outcomes of the LPA2005 trial with the preceding PETHEMA trials using non-age-adapted schedules (LPA96&LPA99). From 1996 to 2012, 389 older patients were registered, of whom 268 patients (69%) were eligible. Causes of ineligibility were secondary APL (19%), and unfit for chemotherapy (11%). Median age was 67 years, without relevant differences between LPA2005 and LPA96&LPA99 cohorts. Overall, 216 patients (81%) achieved complete remission with no differences between trials. The 5-year NRM, cumulative incidence of relapse, disease-free survival and overall survival in the LPA2005 vs the LPA96&99 were 5 vs 18% (P=0.15), 7 vs 12% (P=0.23), 87 vs 69% (P=0.04) and 74 vs 60% (P=0.06). A less intensive front-line regimen with ATRA and anthracycline monochemotherapy resulted in improved outcomes in older APL patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Promielocítica Aguda/tratamento farmacológico , Idoso , Antraciclinas/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão/métodos , Fatores de Risco , Resultado do Tratamento , Tretinoína/administração & dosagem
5.
Steroids ; 100: 36-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25937081

RESUMO

The regioselective opening of the F ring of 22-oxo-23-spiroketals using BF3·OEt2 in acetic anhydride yielded novel cholestanic frameworks with pyranone E ring 20-23. The structures of the new derivatives of botogenin, diosgenin, hecogenin and tigogenin thus obtained were established using one and two dimensional (1)H, (13)C experiments (DEPT, COSY, HETCOR, HMBC). The X-ray diffraction analysis unequivocally confirmed the R configuration at C-23 in the starting 22-oxo-23-spiroketal 18 and the Z configuration of the C23-C24 double bond in the reaction product 20.


Assuntos
Boranos/química , Éter/química , Furanos/química , Compostos de Espiro/química , Catálise , Cristalografia por Raios X , Conformação Molecular , Estereoisomerismo
6.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 11): o1195-6, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484825

RESUMO

In the title compound, C14H10ClNO2, obtained by the condensation of 4-chloro-aniline and piperonal, the five-membered ring is almost planar (r.m.s. deviation = 0.023 Å) and the dihedral angle between the aromatic rings is 43.22 (14)°. In the crystal, a short O⋯Cl contact of 3.173 (2) Šis observed. The mol-ecules are arranged into corrugated (010) layers.

7.
Transplant Proc ; 45(10): 3665-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24314990

RESUMO

The role of hemopoietic stem cell transplantation (HSCT) is not well established in certain types of lymphoma, such as those with a high relapse risk or relapsing after initial therapy. New chemotherapeutic schemes and immunotherapy have improved survival of these patients. Nevertheless, there is not enough evidence regarding whether transplantation is the best therapeutic approach. Moreover, published data on long-term follow-up of high-risk lymphoma patients treated with HSCT are scarce. We analyzed 177 consecutive patients diagnosed with a high risk of relapse or with relapsed lymphoma who underwent HSCT after induction with standard chemotherapy in a tertiary academic center from 1989 to 2013. The median age was 40 years. Diagnoses were Hodgkin disease (n = 56), diffuse large B-cell lymphoma (n = 44), follicular lymphoma (n = 29), mantle cell lymphoma (n = 15), T-cell lymphoma (n = 18), and others (n = 15). Patients received either an autologous graft (n = 154) in first complete remission (1CR; n = 59) or more advanced stages (AS; n = 95), or an allogeneic graft (n = 23) in 1CR (n = 4) or AS (n = 19). In the autologous group, overall survival (OS) at 5 years was 57% and 75% in the periods 1989-2001 and 2002-2013, respectively (P = .05). Patients receiving an allogeneic graft presented an OS of 25% and 43% in the 2 periods. With a mean follow-up of 5 years (95% confidence interval 3.5-6.6), for patients receiving a transplant in 1CR, OS at 5 years was 80%, and for those receiving a transplant in AS it was 59% (P = .003). Nonrelapse mortality (NRM) at 5 years was 3.1% in the autologous group and 27.9% in the allogeneic group (P < .001). The main cause of NRM was infection (44%) in the whole cohort. All this leads to the conclusion that transplantation, as a therapeutic strategy, has shown a high long-term OS in this subgroup of patients with such a poor prognosis. OS improved over the years and reaching 1CR was a good prognostic feature. Infections were the main cause of NRM.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfoma/cirurgia , Terapia de Salvação , Adolescente , Adulto , Criança , Doenças Transmissíveis/etiologia , Doenças Transmissíveis/mortalidade , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Estimativa de Kaplan-Meier , Linfoma/mortalidade , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Recidiva , Fatores de Risco , Centros de Atenção Terciária , Fatores de Tempo , Transplante Autólogo , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
8.
Waste Manag ; 33(12): 2607-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24035245

RESUMO

The increasing generation of municipal solid waste (MSW) is a major problem particularly for large urban areas with insufficient landfill capacities and inefficient waste management systems. Several options associated to the supply chain for implementing a MSW management system are available, however to determine the optimal solution several technical, economic, environmental and social aspects must be considered. Therefore, this paper proposes a mathematical programming model for the optimal planning of the supply chain associated to the MSW management system to maximize the economic benefit while accounting for technical and environmental issues. The optimization model simultaneously selects the processing technologies and their location, the distribution of wastes from cities as well as the distribution of products to markets. The problem was formulated as a multi-objective mixed-integer linear programing problem to maximize the profit of the supply chain and the amount of recycled wastes, where the results are showed through Pareto curves that tradeoff economic and environmental aspects. The proposed approach is applied to a case study for the west-central part of Mexico to consider the integration of MSW from several cities to yield useful products. The results show that an integrated utilization of MSW can provide economic, environmental and social benefits.


Assuntos
Planejamento de Cidades , Modelos Teóricos , Gerenciamento de Resíduos , México , Meios de Transporte
9.
Colloids Surf B Biointerfaces ; 111: 741-6, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23916964

RESUMO

The relationship between electrical conductivity, structure and antibacterial properties of chitosan-silver nanoparticles (CS/AgnP) biocomposites has been analyzed. To test the film's antimicrobial activity, Gram-positive and Gram-negative bacteria were studied. The interactions between silver nanoparticles with chitosan suggest the formation of silver ions which plays a major role in nanocomposite's bactericidal potency. In CS/AgnP biocomposites, the bactericide effectiveness increases by increasing AgnP concentrations up to 3 wt%, which is close to the electrical percolation threshold of ca. 3 wt%. As the AgnP concentration increases above this threshold, the bactericidal potency is greatly diminished. The elucidated correlation between electrical conductivity and antibacterial activity could be useful in the design of other nanocomposites that involve polymeric-based matrices.


Assuntos
Antibacterianos/farmacologia , Quitosana/farmacologia , Condutividade Elétrica , Prata/farmacologia , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Med Mycol ; 51(2): 150-4, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22712457

RESUMO

Caspofungin is an echinocandin with proven efficacy in invasive candidiasis (IC) and invasive aspergillosis (IA). This multicenter, prospective, non-comparative, observational ProCAS study was aimed to assess the effectiveness and safety of caspofungin in adult hematological patients with IC or IA under everyday clinical conditions. Favorable outcomes included complete and partial responses on the last day of caspofungin therapy. Safety was assessed up to 14 days post-caspofungin. A total of 115 patients (69 male) with a median age of 52 years (range, 23-78 years) were analyzed. Underlying disease was acute myeloid leukemia in 45 patients (39%), and 21 (18%) were allogeneic stem cell transplant recipients. Thirty-four (29.5%) patients had a diagnosis of IA and 26 (22.6%) had IC (candidemia). The median duration of caspofungin therapy was 14 days (range, 1-100). The overall favorable response rate was 77% (20/26) for patients with IC (69% first-line) and 79% (27/34) for those with IA. Antifungal therapy with caspofungin was generally well tolerated, only two (1.7%) patients having a non-serious drug-related adverse reaction. These results suggest that caspofungin, either alone or in combination, should be considered an effective and safe option for the treatment of invasive mycoses in patients with severe hematological disorders.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Candidemia/tratamento farmacológico , Candidíase Invasiva/tratamento farmacológico , Equinocandinas/uso terapêutico , Adulto , Idoso , Aspergilose/complicações , Aspergilose/microbiologia , Aspergillus/efeitos dos fármacos , Aspergillus/isolamento & purificação , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidemia/complicações , Candidemia/microbiologia , Candidíase Invasiva/complicações , Candidíase Invasiva/microbiologia , Caspofungina , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Leucemia Mieloide Aguda/complicações , Lipopeptídeos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Segurança , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
11.
J Hematother Stem Cell Res ; 9(1): 83-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10738975

RESUMO

BMT is used as an established therapy for patients with malignant and nonmalignant diseases. Many techniques for ex vivo treatment have been developed, but these techniques must be preceded by BM processing. We report our experience in processing 99 BM using the Fenwal CS-3000 Plus cell separator using the 1-special program. Ninety-nine procedures were performed in BM harvested from 73 patients and 26 healthy donors. The number of nucleated cells (NC), mononuclear cells (MNC), RBC, platelets, colony-forming units-granulocyte-macrophage (CFU-GM), CD34+ cells, relative purity of MNC and PMN, and volume were determined in the unprocessed BM and in the final product. BM processing resulted in NC, MNC, CFU-GM, and CD34+ cell recoveries of 31%, 82.2%, 117.6%, and 97.8%, respectively. RBC, PMN, platelets, and volume removal, respectively, were 96%, 92%, 37.2%, and 85.1%. In pediatric patients, the volume reduction was significantly lower than in adult patients (79.6% versus 88.8%). No other significant differences were found between pediatric and adult results. We conclude that BM processing with the Fenwal CS-3000 Plus cell separator provides a product that can undergo further ex vivo treatments or cryopreservation.


Assuntos
Medula Óssea , Separação Celular/métodos , Adulto , Antígenos CD34 , Plaquetas , Separação Celular/instrumentação , Separação Celular/normas , Criança , Eritrócitos , Neoplasias Hematológicas/patologia , Humanos , Leucócitos Mononucleares , Células-Tronco , Fatores de Tempo
13.
Sangre (Barc) ; 42(3): 179-82, 1997 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-9381258

RESUMO

BACKGROUND: It is a very well-known fact the relationship between pregnancy with history of fetal losses and positive aCL, and many treatments have been tried in order to prevent it. We present a study about the treatment of these pregnant women with ASA at low doses. PATIENTS AND METHODS: We have followed-up a group of 28 women with previous abortions and positive aCL. They were treated with ASA (50 mg/day) since beginning until end of pregnancy. We measured aCL levels monthly. RESULTS: 24 cases of pregnancy (86%) were successfully, 3 cases were fetal losses and 1 case was a fetal malformation. IgG aCL were positive in 16 patients before treatment, and IgM aCL in 11 cases. One patient had both of them. 18 patients became negative after pregnancy. We have not found any relationship between the level of aCL and fetal losses. CONCLUSIONS: In our study, ASA at low doses (50 mg/day) is a safe and effective treatment in achieving successful pregnancies, and reducing aCL levels in patients with history of fetal losses.


Assuntos
Aborto Habitual/prevenção & controle , Anticorpos Anticardiolipina/sangue , Síndrome Antifosfolipídica/complicações , Aspirina/uso terapêutico , Doenças Autoimunes/complicações , Inibidores de Ciclo-Oxigenase/uso terapêutico , Aborto Habitual/etiologia , Aborto Habitual/imunologia , Adulto , Anticorpos Anticardiolipina/imunologia , Síndrome Antifosfolipídica/tratamento farmacológico , Síndrome Antifosfolipídica/imunologia , Aspirina/administração & dosagem , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Inibidores de Ciclo-Oxigenase/administração & dosagem , Feminino , Morte Fetal , Humanos , Hidrocefalia/embriologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Recém-Nascido , Gravidez , Resultado da Gravidez
14.
Ann Hematol ; 74(5): 243-6, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9200998

RESUMO

A case of CLL with two different cellular populations is reported. A 50-year-old man was evaluated for persistent absolute lymphocytosis. A peripheral blood smear revealed numerous small lymphocytes (83% of white blood cells counted). Frequent Grumpecht shadows were present, too. On bone marrow aspirate smears lymphocytes comprised 85% of the total cells counted, and the bone marrow biopsy showed a mixed nodular-interstitial infiltration pattern. The immunophenotypic study showed two different leukemic populations. The first one (comprising 79% leukemic cells) was CD5+, CD19+, CD10-, CD20+, CD18-, CD22-, CD23+ +, lambda dim, and FMC7-. The second population (comprising 21% leukemic cells) was CD5+, CD19+, CD10-, CD20+, CD18+, CD22+, CD23+, lambda+ +, and FMC7+. Gene rearrangement studies detected the germline and one rearranged band in Jk blot with each restriction endonuclease. In the Jh blot the germline and two rearranged bands were detected with EcoRI and BamHI and three rearranged bands with HindIII. The JBI/JBII blot detected only the germline band. The detection of three rearranged bands was interpreted as evidence of the presence of at least two monoclonal populations of cells with the same light chain restriction.


Assuntos
Leucemia Linfocítica Crônica de Células B/patologia , Células Clonais , Rearranjo Gênico do Linfócito B , Rearranjo Gênico do Linfócito T , Humanos , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Masculino , Pessoa de Meia-Idade
15.
Sangre (Barc) ; 41(1): 55-8, 1996 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-8779036

RESUMO

We studied a discrepancy between red blood cells and serum test. The red cell test was identified as an A group, and the serum test as an AB group. Then we performed adsorption-elution and saliva test, in order to demonstrate A, B and H substances. We found that the blood group was AB, and the B antigen belonged to a weak group named Bel. We studied her parent blood groups. Her mother was AB and her father 0. We conclude that the blood group belonged to an cis-AB phenotype and the B antigen was a weak Bel variant.


Assuntos
Sistema ABO de Grupos Sanguíneos/sangue , Tipagem e Reações Cruzadas Sanguíneas , Sistema ABO de Grupos Sanguíneos/classificação , Sistema ABO de Grupos Sanguíneos/genética , Adulto , Feminino , Genótipo , Humanos , Masculino , Fenótipo , Proteínas e Peptídeos Salivares/análise
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