Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Bone Marrow Transplant ; 58(5): 478-490, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36849807

RESUMO

Cardiovascular diseases are an emerging cause of mortality and morbidity in survivors of hematopoietic stem cell transplantation (HSCT); however, the incidence of cardiovascular events (CVEs) in this population is not well described. This systematic review summarizes the evidence on the incidence of CVEs in HSCT recipients. Medline and Embase were searched from inception to December 2020. Inclusion criteria were cohort studies and phase 3 randomized controlled trials that reported CVEs among adults who underwent HSCT for hematological malignancies. After reviewing 8386 citations, 57 studies were included. The incidence of CVEs at 100 days was 0.19 (95% CI: 0.17-0.21) per 100 person-days after autologous HSCT and 0.06 (95% CI: 0.05-0.07) per 100 person-days after allogeneic HSCT. This higher incidence after autologous HSCT was driven by reports of arrhythmia from one population-based study in patients with multiple myeloma. The incidence of long-term CVEs was 3.98 (95% CI; 3.44-4.63) per 1000 person-years in survivors of autologous HSCT and 3.06 (95% CI; 2.69-3.48) per 1000 person-years in survivors of allogeneic HSCT. CVEs remain an important but under-reported cause of morbidity and mortality in recipients of HSCT. Future studies are required to better understand the incidence and risk factors for CVEs in HSCT recipients.


Assuntos
Doenças Cardiovasculares , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante Autólogo/efeitos adversos , Estudos de Coortes , Fatores de Risco , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
2.
Nanotechnology ; 22(24): 245704, 2011 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21508499

RESUMO

Impurity incorporation into nanoparticles is modeled using thermodynamics. For small particles, entropically driven impurity incorporation is reduced, rendering doping difficult. We show that the free energy of surface impurities in small nanoparticles is lower than core impurities, surface doping therefore occurs preferentially. A critical size for core doping is identified, below which it is energetically unfavorable. In all cases, core impurity concentration is reduced as particle size decreases. We show larger than bulk impurity concentrations are possible, corresponding to increased alloying.

3.
J Control Release ; 54(3): 251-64, 1998 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-9766245

RESUMO

A study has been made of the kinetics of release into water of a model disperse dye (4-aminoazobenzene) from supersaturated solvent-cast cellulose acetate films at room temperature. Excess dye was introduced into the polymer matrix by: (i) sorption from aqueous solution at 100 degrees C; (ii) sorption from the vapour phase at 110 degrees C; or (iii) prior dissolution in the casting solvent. The effect of the method of introduction of the dye, the degree of supersaturation and the rate of agitation of the bath were investigated. Under conditions of strong agitation, the release kinetics from films dyed by method (i) or (iii) were in general accord with the theoretical model which assumes solute in the film in excess of the saturation limit to be in the form of immobile aggregates at equilibrium with mobile dye; although the value of the diffusion coefficient of the solute in the film was found to be substantially higher than that in the unsaturated film. On the other hand, when dyeing had been effected from the vapour phase, Fickian kinetics was followed and the diffusion coefficient was found to be equal to that observed in unsaturated film. It was concluded that under these conditions, the excess dye in the film tends to remain molecularly dispersed. Under conditions of slow agitation, the square root of t kinetics was not attained in many instances. General and early-time approximate expressions based on the Roseman-Higuchi model proved useful for the interpretation of the results in such cases; while the said model was extended to include the effect of significant variation of the partition coefficient of the solute with concentration.


Assuntos
Materiais Biocompatíveis/química , Celulose/análogos & derivados , Corantes/química , Algoritmos , Celulose/química , Fenômenos Químicos , Físico-Química , Cinética , Modelos Teóricos , Soluções , p-Aminoazobenzeno
4.
Ophthalmic Surg Lasers ; 30(8): 647-52, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10507567

RESUMO

BACKGROUND AND OBJECTIVE: To evaluate the efficacy of topical brimonidine tartrate 0.2% (Allergan, Irvine, CA) in the prophylactic treatment of acute intraocular pressure (IOP) rises following Nd:YAG laser posterior capsulotomy. PATIENTS AND METHODS: This was a double-masked, randomized, placebo-controlled clinical study in 60 patients who underwent Nd:YAG laser posterior capsulotomy after extracapsular cataract extraction. Two doses of brimonidine or vehicle were administered before and after capsulotomy. Intraocular pressure was measured prior to commencing instillation and for 48 hours postoperatively. RESULTS: Following posterior capsulotomy, the brimonidine group showed a significant mean percent reduction in IOP, while the vehicle group showed a significant mean percent increase in IOP. At 48 hours, mean IOP of both groups had returned to pre-laser level. There were no differences between the 2 groups in the incidence of clinical adverse experiences. CONCLUSION: Two-dose brimonidine tartrate 0.2% effectively prevents acute IOP rises after Nd:YAG laser posterior capsulotomy.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Intraocular/efeitos dos fármacos , Terapia a Laser/efeitos adversos , Cápsula do Cristalino/cirurgia , Hipertensão Ocular/prevenção & controle , Quinoxalinas/uso terapêutico , Doença Aguda , Administração Tópica , Idoso , Anti-Hipertensivos/administração & dosagem , Tartarato de Brimonidina , Extração de Catarata , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/etiologia , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/uso terapêutico , Quinoxalinas/administração & dosagem
5.
J Fr Ophtalmol ; 25(8): 813-6, 2002 Oct.
Artigo em Francês | MEDLINE | ID: mdl-12471348

RESUMO

We present the case of a 32-year-old man suffering from multiple sclerosis who had developed bilateral peripheral neovascularization of the retina. The main disease had been diagnosed 10 years before, whereas in his ophthalmic history the patient reported an incident of retrobulbar optic neuritis in his left eye occurring 3 years before. The patient was referred to our clinic in order to investigate the cause of a sudden loss of vision in his left eye. Ophthalmic examination and fluorescein angiography revealed the presence of a bilateral peripheral retinal neovascularization with an intravitreous hemorrhage in the left eye. Systemic clinical and laboratory investigation were negative for other causes of retinal neovascularization except multiple sclerosis, which is associated with periphlebitis in 10% of cases. Chronic retinal ischemia may lead to retinal neovascularization.


Assuntos
Esclerose Múltipla/complicações , Neovascularização Retiniana/etiologia , Adulto , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Humanos , Fotocoagulação a Laser , Masculino , Neovascularização Retiniana/diagnóstico , Neovascularização Retiniana/cirurgia , Fatores de Tempo , Acuidade Visual
7.
Bioseparation ; 1(1): 69-88, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1368162

RESUMO

A restricted diffusion model is constructed and solved in order to study the permeability of large adsorbate molecules in the pores of affinity chromatography media, when the adsorbate molecules are adsorbed onto immobilized ligands. The combined effects of steric hindrance at the entrance to the pores and frictional resistance within the pores, as well as the effects of pore size distribution, pore connectivity of the adsorbent, molecular size of adsorbate and ligand, and the fractional saturation of adsorption sites (ligands), are considered. Affinity adsorbents with dilute and high ligand concentrations are examined, and the permeability of the adsorbate in porous networks of connectivity nT is studied by means of effective medium approximation (EMA) numerical solutions. As expected, the permeability of the adsorbate decreases as the size of the adsorbate and/or ligand molecule increases. The permeability also decreases when the fractional saturation of the ligands increases, as well as when the pore connectivity of the network decreases. The dependence of the permeability on the pore connectivity tends to be less marked in adsorbents with concentrated ligand than in porous media with dilute ligand concentration. The conditions are also presented for which the percolation threshold is attained in a number of different systems. The restricted diffusion model and results of this work may be of importance in studies involving the modeling, prediction of the dynamic behavior, design, and control of affinity chromatography (biospecific adsorption) systems employing porous adsorbents. The theoretical results may also have important implications in the selection of a ligand as well as in the selection and construction of an affinity porous matrix, so that the adsorbate of interest can be efficiently separated from a given solution. Furthermore, with appropriate modifications this restricted diffusion model may be used in studies involving the immobilization of ligands or enzymes in porous solids.


Assuntos
Cromatografia de Afinidade , Adsorção , Difusão , Ligantes , Modelos Teóricos , Permeabilidade , Terminologia como Assunto
8.
Infection ; 30(4): 229-33, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12236567

RESUMO

BACKGROUND: The aim of this study was to determine the prevalence of keratoconjunctivitis sicca (KCS) in Greek patients with chronic hepatitis C virus (HCV) infection and its association with HCV genotypes and liver histology. PATIENTS AND METHODS: 93 HCVAb (+) patients underwent lacrimal function testing (Schirmer-1 test, break-up time test and Rose-Bengal staining test) and estimation of serum cryoglobulins and autoantibodies. 80 healthy volunteers were included in the study as controls. RESULTS: 34 out of 93 HCV patients (36.6%) and eight out of 80 healthy subjects (10%) had at least two abnormal lacrimal function tests suggestive of KCS (p < 0.001), cryoglobulinemia was evident in 20 patients (21.5%), rheumatoid factor (RF) in 43 (46.2%), antinuclear antibodies (ANA) in 19 (20.4%), antinuclear antigens (anti-SS-A and anti-SS-B) in one (1.1%) and two (2.2%) patients, respectively. Reduced prevalence of KCS was found in patients with genotype 3a compared to those with other genotypes (5/30, 16.7% vs 20/42, 47.6%, p = 0.007), probably because of their younger age. In patients with KCS a higher staging score was noted in liver biopsy compared to those without KCS (4.50 +/- 1.65 vs 3.06 +/- 1.88, p = 0.005). CONCLUSION: Greek patients with chronic HCV infection have a high prevalence of KCS (36.6%). The low frequency of anti-SS-A and anti-SS-B antibodies in these patients denotes different pathogenetic associations from primary Sjogren's syndrome.


Assuntos
Hepacivirus/imunologia , Hepatite C Crônica/complicações , Ceratoconjuntivite Seca/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antinucleares/análise , Anticorpos Antivirais/análise , Biópsia , Feminino , Grécia/epidemiologia , Humanos , Ceratoconjuntivite Seca/epidemiologia , Ceratoconjuntivite Seca/imunologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Prevalência
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa