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1.
Scand J Public Health ; 49(8): 884-890, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33615897

RESUMO

AIM: To study what medication fathers are being prescribed in the months preceding conception. METHODS: A retrospective cohort study of Danish national registries, comprising all births in Denmark 1997-2017 (1.3 million births). Time trends and absolute levels of paternal prescription medication in the 6 months prior to conception were assessed. While all medications were examined (N = 1335), we focused on the main medication groups, medications that have increased in use over time, and medications for which previous evidence exists of an effect on sperm quality. RESULTS: The average number of prescriptions increased over the study period (from 0.75 prescriptions to 0.82 per birth). Polypharmacy (three or more prescriptions) increased from less than 8% to 10% of fathers. The use of pain medication, proton-pump inhibitors, selective serotonin reuptake inhibitors and some inhalants have all increased markedly over the last 20 years. CONCLUSIONS: Potential harm to the offspring done by paternal medication may present an increasing problem. As paternal medication exposure is increasing, examination of generational effects, such as major birth defects, is necessary.


Assuntos
Pai , Exposição Paterna , Dinamarca/epidemiologia , Humanos , Masculino , Exposição Paterna/efeitos adversos , Prescrições , Estudos Retrospectivos
2.
Biophys J ; 100(2): 284-93, 2011 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-21244824

RESUMO

Reductionist in vitro model systems which mimic specific extracellular matrix functions in a highly controlled manner, termed artificial extracellular matrices (aECM), have increasingly been used to elucidate the role of cell-ECM interactions in regulating cell fate. To better understand the interplay of biophysical and biochemical effectors in controlling three-dimensional cell migration, a poly(ethylene glycol)-based aECM platform was used in this study to explore the influence of matrix cross-linking density, represented here by stiffness, on cell migration in vitro and in vivo. In vitro, the migration behavior of single preosteoblastic cells within hydrogels of varying stiffness and susceptibilities to degradation by matrix metalloproteases was assessed by time-lapse microscopy. Migration behavior was seen to be strongly dependent on matrix stiffness, with two regimes identified: a nonproteolytic migration mode dominating at relatively low matrix stiffness and proteolytic migration at higher stiffness. Subsequent in vivo experiments revealed a similar stiffness dependence of matrix remodeling, albeit less sensitive to the matrix metalloprotease sensitivity. Therefore, our aECM model system is well suited to unveil the role of biophysical and biochemical determinants of physiologically relevant cell migration phenomena.


Assuntos
Técnicas de Cultura de Células/métodos , Movimento Celular/fisiologia , Matriz Extracelular/fisiologia , Metaloproteinases da Matriz/fisiologia , Animais , Comunicação Celular/fisiologia , Diferenciação Celular , Linhagem Celular , Elasticidade , Hidrogéis/química , Camundongos , Polietilenoglicóis/química , Ratos , Ratos Sprague-Dawley
3.
Br J Anaesth ; 106(5): 690-4, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21414982

RESUMO

BACKGROUND: The aim of recent haemodynamic monitoring has been to obtain continuous and reliable measures of cardiac output (CO) and indices of preload responsiveness. Many of these methods are based on the arterial pressure waveform analysis. The aim of our study was to assess the accuracy of CO measurements obtained by FloTrac/Vigileo, software version 1.07 and the new version 1.10 (Edwards Lifesciences LLC, Irvine, CA, USA), compared with CO measurements obtained by bolus thermodilution by pulmonary artery catheterization (PAC) in the intensive care setting. METHODS: In 21 critically ill patients (enrolled in two University Hospitals), requiring invasive haemodynamic monitoring, PAC and FloTrac/Vigileo transducers connected to the arterial pressure line were placed. Simultaneous measurements of CO by two methods (FloTrac/Vigileo and thermodilution) were obtained three times a day for 3 consecutive days, when possible. The level of concordance between the two methods was assessed by the procedure suggested by Bland and Altman. RESULTS: One hundred and forty-one pairs of measurements (provided by thermodilution and by both 1.07 and 1.10 FloTrac/Vigileo versions) were obtained in 21 patients (seven of them were trauma patients) with a mean (sd) age of 59 (16) yr. The Pearson product moment coefficient was 0.62 (P<0.001). The bias was -0.18 litre min(-1). The limits of agreement were 4.54 and -4.90 litre min(-1), respectively. CONCLUSIONS: Our data show a poor level of concordance between measures provided by the two methods. We found an underestimation of CO values measured with the 1.07 software version of FloTrac for supranormal values of CO. The new software (1.10) has been improved in order to correct this bias; however, its reliability is still poor. On the basis of our data, we can therefore conclude that both software versions of FloTrac/Vigileo did not still provide reliable estimation of CO in our intensive care unit setting.


Assuntos
Débito Cardíaco , Cuidados Críticos/métodos , Estado Terminal/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Reprodutibilidade dos Testes , Termodiluição , Transdutores de Pressão
4.
Ann Oncol ; 20(1): 129-36, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18718888

RESUMO

BACKGROUND: Among marginal zone lymphomas (MZLs), bone marrow (BM) involvement features are well established in the splenic marginal zone lymphoma (SMZL); few data are available for extranodal marginal zone lymphoma (EMZL) and nodal marginal zone lymphoma (NMZL). PATIENTS AND METHODS: Incidence and patterns of histologic BM involvement are studied in 120 MZL patients (48 SMZL, 59 EMZL, 13 NMZL) at onset and during follow-up; relationships between clinical features, BM histology and flow cytometry (FC) are analyzed. RESULTS: At diagnosis, BM involvement occurs in 90% SMZL, 22% EMZL and 54% NMZL (P<0.0001); at reevaluation, incidence raises to 96% in SMZL and 34% in EMZL. Concordance between histology and FC is found in 87% of cases; most discordant cases have positive histology but negative FC. SMZL and EMZL show a nodular BM infiltration; the interstitial pattern is frequent in NMZL (P<0.0001); sinusoidal localization is typical of SMZL, frequent in NMZL and occasional in EMZL (P=0.0001). Stage, leukemic disease, B symptoms, more than one extranodal involved site, splenomegaly, elevated beta2-microglobulin, serum monoclonal component, International Prognostic Index (IPI) and age-adjusted IPI are directly related to BM infiltration. CONCLUSIONS: The different prevalence of BM involvement in MZL subtypes reflects their heterogeneous dissemination modalities; histology seems more sensible than FC to detect BM infiltration; development of BM involvement during follow-up is typical of EMZL.


Assuntos
Neoplasias da Medula Óssea/epidemiologia , Neoplasias da Medula Óssea/secundário , Medula Óssea/patologia , Linfoma de Zona Marginal Tipo Células B/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Medula Óssea/patologia , Progressão da Doença , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Incidência , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Transplant Proc ; 40(6): 2070-2, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18675133

RESUMO

Severe infectious diseases after liver transplant are associated with high risk of multiorgan failure and mortality. Septic shock is difficult to manage in this setting since it is often unresponsive to conventional aggressive therapy. Adjuvant therapies have been proposed in association with full combination treatment to sustain the failing organs and improve outcomes in severe sepsis. Recombinant human activated protein C drotrecogin alfa, Xigris) has been occasionally administered to treat posttransplant sepsis to modulate and downregulate the complex network of inflammatory and coagulopathic processes. Herein we have reported on a patient who was given drotrecogin alfa 15 days following liver transplant for acute septic shock originating from a nosocomially acquired pneumonia. Recombinant activated drotrecogin alfa, associated with conventional aggressive treatment, was efficacious to revert the life-threatening "slippery slope" of vasoplegia and uncontrolled diffuse inflammation.


Assuntos
Fibrinolíticos/uso terapêutico , Transplante de Fígado/efeitos adversos , Proteína C/uso terapêutico , Choque Séptico/tratamento farmacológico , Infecção Hospitalar/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/complicações , Complicações Pós-Operatórias/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico
6.
Transplant Proc ; 39(6): 1889-91, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17692644

RESUMO

Bacterial contamination is one of the potential risks of blood salvage and reinfusion during orthotopic liver transplantation (OLT) because cell-saver machines lack antibacterial protection devices. This study was designed to analyze the potential bacterial contamination of blood salvaged during OLT; a secondary end point was to evaluate whether reinfusion of potentially contaminated blood may have been responsible for clinically manifested infective complications in the same patient. After induction of anesthesia, a blood sample was drawn from the central venous catheter (CVC) immediately after its positioning, to exclude potential coexisting hematic contamination of the recipient. During the procedure, 2 other samples of salvaged blood were collected for bacteriological analysis. Twenty-six of 38 samples of salvaged blood were positive for microorganisms, whereas 12 did not reveal the presence of infectious agents. In 19 of 26 positive samples, Staphylococcus species (73%) were isolated with only 2 of 38 samples drawn from CVC being contaminated. Candida Albicans was cultured in 2 samples. The high percentage (73%) of coagulase-negative Staphylococci indicates that blood contamination could have been caused by microorganisms from the air or suctioned from contact surfaces and the surgical field. Although almost 70% of processed and reinfused units tested positive for microbes, none of the postoperative blood cultures (at day 1 and day 3) revealed growth of the same species, not even in the 2 patients who had positive CVC cultures after induction of anesthesia.


Assuntos
Perda Sanguínea Cirúrgica , Período Intraoperatório , Transplante de Fígado/efeitos adversos , Adolescente , Adulto , Idoso , Transfusão de Sangue Autóloga , Candida albicans/isolamento & purificação , Contaminação de Equipamentos , Escherichia coli/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Staphylococcus/isolamento & purificação , Reação Transfusional
7.
Transplant Proc ; 39(6): 1976-80, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17692670

RESUMO

Lung transplantation has become a consolidated treatment for patients with severe pulmonary hypertension (PH). Several difficulties are encountered during the procedure in such candidates, who are still recognized as more severely affected by perioperative morbility and mortality than those undergoing lung transplantation for other diseases. Right ventricular (RV) enlargement with tricuspid regurgitation, small left ventricle (LV) with an asymmetric hypetrophic wall, interventricular septal shift toward the left, with ventricular stiffness and diastolic incompetence, are typical preoperative echocardiographic findings of end-stage PH. A smooth induction and tracheal intubation will help prevent hypertensive crisis in highly susceptible candidates. Uncompensated vasodilatation or myocardial depression caused by anesthetics and mechanical ventilation may be responsible for acute RV dysfunction associated with low systemic blood pressure. Resuscitation and emergency adoption of cardiopulmonary by-pass (CPB) has been described for near-fatal anesthesia induction. Cardiovascular instability can develop after institution of one-lung ventilation and pulmonary artery clamping. An acute increase in pulmonary pressure results in a decrease in RV ejection fraction and then in acute RV failure. Interdependence of the right and left ventricles occurs such that RV function can alter LV function. Early detection of impending circulatory and/or respiratory deterioration is warranted to prevent an irreversible decline in cardiac output, resulting in hazardous cardiac arrest. Inhaled nitric oxide represents the first choice for treatment of PH and RV failure associated with systemic hypotension during lung transplantation. Intraoperative situations requiring CPB must be identified before development of systemic shock, which represents a late ominous sign of RV failure.


Assuntos
Anestesia/efeitos adversos , Hipertensão Pulmonar/cirurgia , Transplante de Pulmão/fisiologia , Anestesia/métodos , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Período Intraoperatório , Monitorização Intraoperatória , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Vasodilatadores/uso terapêutico
8.
Nucleic Acids Res ; 28(12): 2383-8, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10871371

RESUMO

Shiga toxin 1 (Stx1) catalyses the removal of a unique and specific adenine from 28S RNA in ribosomes (RNA-N-glycosidase activity) and the release of multiple adenines from DNA (DNA glycosylase activity). Added adenine behaves as an uncompetitive inhibitor of the RNA-N-glycosidase reaction binding more tightly to the Stx1-ribosome complex than to the free enzyme. Several purine derivatives and analogues have now been assayed as inhibitors of Stx1. Most of the compounds showed only minor differences in the rank order of activity on the two enzymatic reactions catalysed by Stx1. The survey highlights the importance of the amino group in the 6-position of the pyrimidine ring of adenine. Shifting (2-aminopurine) or substituting (hypoxanthine, 6-mercapto-purine, 6-methylpurine) the group greatly decreases the inhibitory power. The presence of a second ring, besides the pyrimidine one, is strictly required. Substitution, by introducing an additional nitrogen, of the imidazole ring of adenine with triazole leads to loss of inhibitory power, while rearrangement of the nitrogen atoms of the ring from the imidazole to the pyrazole configuration greatly enhances the inhibitory power. Thus 4-aminopyrazolo[3,4-d]pyrimidine (4-APP), the isomer of adenine with the five-membered ring in the pyrazole configuration, is by far the most potent inhibitor of both enzymatic reactions catalysed by Stx1. This finding opens perspectives on therapeutic strategies to protect endothelial renal cells once endocytosis of Stx1 has occurred (haemolytic uraemic syndrome). In the RNA-N-glycosidase reaction 4-APP binds, as adenine, predominantly to the Stx1-ribosome complex (uncompetitive inhibition), while inhibition of the DNA glycosylase activity by both inhibitors is of the mixed type.


Assuntos
Azidas/farmacologia , Toxinas Bacterianas/farmacologia , Citotoxinas/farmacologia , DNA/metabolismo , N-Glicosil Hidrolases/antagonistas & inibidores , Purinas/farmacologia , Pirimidinas/farmacologia , RNA Ribossômico 28S/metabolismo , Adenina/farmacologia , Marcadores de Afinidade , Toxinas Bacterianas/antagonistas & inibidores , DNA Glicosilases , Cinética , Proteínas Recombinantes/farmacologia , Proteínas Inativadoras de Ribossomos , Toxinas Shiga
9.
Transplant Proc ; 38(3): 786-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16647470

RESUMO

Fulminant hepatic failure (FHF) is often complicated with cerebral edema, intracranial hypertension, and coma. Cytotoxic and vasogenic factors have been recognized in the etiology of cerebral edema. One of the main causes seems to be the accumulation of glutamine in astrocytes, which is produced from ammonia and the excitatory neurotransmitter glutamate. Ammonia is detoxified within the brain in astrocytes, where it increases the osmotic pressure for water. Ammonia-induced astrocytic water accumulation seems to act as an integrative trigger for the development of intracranial hypertension. While cerebral blood flow is sometimes reduced in the first stage of FHF, as compensatory cerebral vasoconstriction to reduce mean arterial pressure, it later increases as hyperammonemia decreases cerebral arteriolar tone. Despite vasodilation in the systemic and splanchnic beds at early stages of the disease, cerebral vessel resistance may increase, so that cerebral perfusion pressure may be preserved. When cerebral vascular tone is no longer effective in the course of illness, vasodilation gradually develops and rapidly becomes poorly responsive to carbon dioxide stimulation, which signifies loss of autoregulatory tone and cerebral hyperemia develops. Prolonged excessive flow may lead to brain swelling, vasogenic edema, and intracerebral hemorrhage. Brain edema further aggravates the critically reduced cerebral perfusion and is responsible for the high mortality.


Assuntos
Circulação Cerebrovascular/fisiologia , Falência Hepática Aguda/fisiopatologia , Velocidade do Fluxo Sanguíneo , Dióxido de Carbono/sangue , Homeostase , Humanos
10.
Bone Marrow Transplant ; 36(4): 289-94, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15968277

RESUMO

Healthy allogeneic donors, who were treated with G-CSF and underwent peripheral blood haematopoietic precursor collection at our Institution, were enrolled in a short- and long-term haematological surveillance protocol for a 5--7--year period. To date, 94 donors have been assessed with a mean follow-up of 30 months (4--84); for 30 subjects, the follow-up is >or=48 months. During G-CSF administration, 23/94 donors showed a significant platelet count decrease from the baseline. Pre-apheresis platelet decrement correlated with the total G-CSF dose administered, baseline platelet level and donor age. Normal platelet counts returned within 4--8 months. PMN and/or lymphocyte lower values were observed in 55/94 donors 2 weeks after G-CSF administration, with mean drops from the baseline of 40 and 36% for PMN and lymphocytes, respectively. The PMN decrease correlated inversely with donor age, as younger donors were more affected than older ones, whereas the lymphocyte decrease correlated directly with the total blood volumes processed in the apheresis courses, in particular for donors subjected to large volume leukaphereses. Long-term observation showed moderate neutrophil reduction (25% count drop from the baseline) in four of the 30 donors observed for four years or more. 14 donors showed persistent, slight lymphocytopenia (mean drop of 13%) until the third year, with recovery in the fourth year of follow-up.


Assuntos
Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Leucaférese , Vigilância da População , Doadores de Tecidos , Adulto , Fatores Etários , Contagem de Células Sanguíneas , Feminino , Seguimentos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Contagem de Linfócitos , Linfopenia/etiologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Transplante de Células-Tronco de Sangue Periférico , Contagem de Plaquetas , Estudos Prospectivos , Fatores de Tempo , Transplante Homólogo
11.
Leukemia ; 14(7): 1310-3, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10914557

RESUMO

Patients with multiple myeloma (MM) and chronic renal failure have generally been excluded from myeloablative therapy programs followed by hematopoietic stem cell support because of the potential increase in transplant-related morbidity and mortality. We here report our experience treating six MM patients with moderate to severe renal insufficiency, with autologous stem cell transplantation. One of these patients required chronic hemodialysis since the diagnosis of MM was made. Peripheral blood stem cell collection was performed with either cyclophosphamide 5.5-7 g/m2 + G-CSF, 5 microg/kg/day (patients 1-3, 5 and 6) or G-CSF, 15 microg/kg/day alone (patient No. 4). Four patients (Nos 1-4) received autotransplant as front-line therapy, while the last two patients were treated in relapse, which occurred following prior autologous stem cell transplantation in support of melphalan, 200 mg/m2 (No. 5) or maintainance therapy with alpha-interferon (No. 6). High-dose chemotherapy administered as preparation to transplant included busulfan 12 mg/kg + melphalan 80 mg/m2 (patients 1-3 and 6) or melphalan 80 mg/m2 alone (patients 4 and 5) in order to reduce mucosal damage. Following transplant, prompt and sustained recovery of hematopoiesis was documented in all the patients; 500 PMN/microI and 20000 platelets/microI were reached after a median of 13 and 14 days, respectively. None of the patients suffered from WHO grade 3-4 infectious complications. Transplant-related toxicity included grade 3-4 oral mucositis (patients 1, 4 and 5) and veno-occlusive disease (patient No. 3). Renal function either improved or remained stable throughout the transplant period. All the patients but one responded to therapy, three of them are progression free after 2, 15 and 26 months; two relapsed after 16 and 4 months and one died from cholangiocarcinoma 7 months after transplant, while still in remission. Although our experience is limited so far, these results appear promising and support the investigational use of myeloablative therapy in MM patients with chronic renal failure.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Falência Renal Crônica/etiologia , Mieloma Múltiplo/terapia , Adulto , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bussulfano/administração & dosagem , Colangiocarcinoma , Terapia Combinada , Creatinina/sangue , Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hepatopatia Veno-Oclusiva/etiologia , Humanos , Hiperbilirrubinemia/etiologia , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Falência Renal Crônica/terapia , Masculino , Melfalan/administração & dosagem , Melfalan/uso terapêutico , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Mieloma Múltiplo/tratamento farmacológico , Segunda Neoplasia Primária , Indução de Remissão , Diálise Renal , Segurança , Estomatite/etiologia , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento , Vincristina/administração & dosagem
12.
Leukemia ; 10(3): 402-9, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8642854

RESUMO

We evaluated the role of ABMT in late 1st CR AML adult patients using busulfan plus cyclophosphamide as preparative regimen. Fifty-one adult patients (mean age 36 years, range 15-59) with AML underwent ABMT in 1st CR. Three of them had a prior diagnosis of myelodysplastic syndrome; one patient had a secondary leukemia. The median interval between CR and ABMT was 8 months (range 4-20). Patients received busulfan, 4 mg/kg/day for 4 days plus cyclophosphamide 50 mg/kg/day for 4 days or 60 mg/kg/day for 2 days. No maintenance chemotherapy was administered after ABMT. Median days to reach 0.5 x 10(9)/I PMN and 20 x 10(9)/I platelets were 26 (range 12-250) and 74 (range 16-740), respectively. No transplant-related deaths were observed. Five-year actuarial overall survival rate is 76.9%; actuarial leukemia-free survival rate is 70.6%. Mean follow-up from ABMT is 35 months. Leukemia-free survival of this group was compared with that of 38 non-transplanted patients younger than 60 years, who maintained a CR longer than 8 months in the same period. This analysis shows a statistically significant difference in favor of ABMT patients. These results suggest that, even if performed late after 1st CR as post-remission intensification, ABMT can improve the outcome of AML patients.


Assuntos
Transplante de Medula Óssea , Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bussulfano/administração & dosagem , Terapia Combinada , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Humanos , Idarubicina/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Indução de Remissão , Taxa de Sobrevida , Fatores de Tempo , Transplante Autólogo
13.
Exp Hematol ; 21(13): 1668-72, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7694867

RESUMO

We have studied the effects of recombinant human interleukin-11 (rhIL-11), alone and combined with stem cell factor (SCF or c-kit ligand), IL-3, and granulocyte-macrophage colony-stimulating factor (GM-CSF) on the proliferation of highly enriched human hematopoietic CD34+ and CD34+CD33-DR- progenitor cells. CD34+ cells were purified using the avidin-biotin immunoabsorption technique and CD33+DR+ cells were subsequently removed by immuno-magnetic separation. The colony assays were performed in the presence and absence of exogenous serum. IL-11, as a single agent, induced the growth of a small number of colony-forming units-granulocyte/macrophage (CFU-GM) derived from purified CD34+ cells and failed to support the colony growth of CD34+CD33-DR- cells. The addition of erythropoietin (Epo) to IL-11 induced the growth of erythroid progenitors (BFU-E) derived from CD34+ cells but not from the same population depleted of CD33+DR+ cells. The combination of IL-11 with SCF, IL-3, or GM-CSF, in the presence of Epo, resulted in a synergistic or additive increase in the number of CFU cells (CFU-C) derived from both cell fractions. Moreover, the addition of SCF to IL-11 stimulated the development of macroscopic erythroid and multilineage colonies (CFU-GEMM) containing more than 10(4) cells. A combination of three factors (IL-11, SCF, and IL-3) resulted in the increase of the number of colonies arising from CD34+ and CD34+CD33-DR- cells (but not of their size) compared to the cultures treated with IL-11 plus SCF or IL-11 plus IL-3. The pattern of proliferative response of primitive hematopoietic progenitor cells to IL-11 in serum-free conditions was very similar to the cultures grown in serum-containing medium. It is noteworthy that IL-11 and SCF yielded colony formation that was comparable to that observed in the presence of serum. The effects of IL-11 on CD34+CD33-DR- cells were also studied in a short-term suspension culture system, which was shown to be specific for evaluating the proliferation of pluripotent hematopoietic precursors (Delta assay). In this system, IL-11 had a minimal effect on its own, whereas IL-11 plus SCF acted synergistically and their proliferative activity was improved by the addition of GM-CSF. These experiments indicate that IL-11 may be considered a "permissive" cytokine, capable of initiating the proliferation of very primitive human hematopoietic cells, which are then able to respond to late-acting CSFs.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Antígenos HLA-DR/análise , Células-Tronco Hematopoéticas/citologia , Interleucina-11/farmacologia , Antígenos CD34 , Sangue , Células da Medula Óssea , Divisão Celular , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Sinergismo Farmacológico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Interleucina-3/farmacologia , Proteínas Recombinantes/farmacologia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Fator de Células-Tronco
14.
Exp Hematol ; 22(9): 919-23, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7520394

RESUMO

We have studied the effects of recombinant human interleukin-9 (IL-9), alone and combined with stem cell factor (SCF, c-kit ligand), IL-3, and granulocyte-macrophage colony-stimulating factor (GM-CSF) on the clonogenic proliferation of highly enriched human hematopoietic CD34+ and CD34+CD33-DR- progenitor cells. Colony assays were performed under serum-containing and serum-free conditions. IL-9, as a single agent, did not support colony formation. The addition of erythropoietin (Epo) to IL-9 induced the growth of erythroid progenitors (BFU-E) derived from both CD34+ and CD34+CD33-DR- cells. The IL-9-dependent growth of BFU-E derived from CD34+ cells was increased in an additive manner by SCF and, to a lesser extent, by IL-3, whereas CD34+CD33-DR- erythroid precursors were also responsive to GM-CSF in combination with IL-9. The addition of SCF to IL-9 did stimulate the development of CD34+ and CD34+CD33-DR- macroscopic, multicentered BFU-E and multilineage colonies (CFU-GEMM). When IL-9 was used in serum-free conditions, the growth of CD34+ and CD34+CD33-DR- BFU-E was observed in the presence of Epo. Moreover, a marked synergy on BFU-E colony formation was evident when IL-9 was combined with SCF, and their activity was enhanced by the addition of IL-3. IL-9 showed a negligible proliferative activity on colony-forming units-granulocyte/macrophage (CFU-GM). However, it increased the number of CD34+CD33-DR- CFU-GM responsive to IL-3 (37% of the colonies generated by phytohemagglutinin-stimulated lymphocyte conditioned medium [PHA-LCM]). The effects of IL-9 on CD34+CD33-DR- cells were also studied in a short-term suspension culture system, which evaluates the proliferation of progenitors earlier than day 14 CFU-C (Delta assay). In this system, IL-9 had a minimal activity on its own. In combination with SCF, however, it induced a nine-fold expansion of CD34+CD33-DR- cells, which generated a greater number of CFU-GM than BFU-E in secondary methylcellulose cultures. These experiments indicate that IL-9 induces the proliferation of very primitive human erythroid cells, and this effect is potentiated by SCF and other cytokines. Furthermore, IL-9 synergizes in vitro with the c-kit ligand in expanding the pool of early pluripotent hematopoietic progenitor cells.


Assuntos
Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Antígenos HLA-DR/análise , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Interleucina-9/farmacologia , Antígenos CD/imunologia , Antígenos CD34 , Antígenos de Diferenciação Mielomonocítica/imunologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura Livres de Soro/farmacologia , Sinergismo Farmacológico , Células Precursoras Eritroides/citologia , Células Precursoras Eritroides/efeitos dos fármacos , Eritropoetina/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Antígenos HLA-DR/imunologia , Hematopoese/efeitos dos fármacos , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Interleucina-3/farmacologia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Fator de Células-Tronco
15.
Exp Hematol ; 25(12): 1261-9, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9357970

RESUMO

UNLABELLED: In this paper we describe an experimental model for ex vivo purging of contaminating tumor cells from peripheral blood stem cell (PBSC) collections obtained from patients with acute myeloblastic leukemia (AML). We studied the combination of the alkylating agent nitrogen mustard (NM; concentrations ranging from 0.25 to 1.25 microg/mL) and etoposide (VP-16; constant dose of 20 microg/mL), and the conventional cyclophosphamide (Cy)-derivative mafosfamide (concentrations: 20-175 microg/mL). THE AIMS OF OUR STUDY WERE: 1) To compare the toxicity of the purging protocols on bone marrow (BM) and circulating trilineage precursors collected from normal donors after priming with granulocyte colony-stimulating factor (G-CSF) or after complete remission (CR) consolidation chemotherapy and G-CSF (leukemic patients); 2) to demonstrate the survival of very primitive hematopoietic progenitors (LTC-IC) in the peripheral blood (PB) and the BM after pharmacological treatment; and 3) to evaluate the antineoplastic efficacy of purging protocols on PBSC collections using 3 well-established leukemic cell lines. Our results demonstrated that the toxicity on BM and PB progenitor cells could be correlated with the complete killing of committed granulocyte-macrophage colony-forming units (CFU-GMs) and erythroid precursors (BFU-Es), a condition reached at the concentration of 1.5 microg/mL of NM (in addition to 20 microg/mL of VP-16) and 175 microg/mL of mafosfamide. Notably, early and late megakaryocyte progenitor cells (CFU-MKs and BFU-MKs, respectively) showed higher sensitivity to NM/VP-16, but not to mafosfamide, than did CFU-GMs and BFU-Es. The dose of NM capable of inhibiting 95% of CFU-MKs and BFU-MKs (ID95) was 0.75 microg/mL. After incubation with the same dose of NM, the recovery of CFU-GMs and BFU-Es was 20 +/- 8% SD and 25 +/- 10% SD, respectively (p < 0.05). Long-term liquid cultures showed the recovery of primitive hematopoietic cells after incubation with the highest concentrations of NM/VP-16 and mafosfamide, with no significant differences between PB and BM samples. Under the same experimental conditions, we observed a more than 5-log reduction of contaminating leukemic cell lines (i.e., K-562, KG-1, and HL-60). In conclusion, we demonstrated that NM/VP-16 and mafosfamide purging agents are capable of killing leukemic cell lines that contaminate leukapheresis products from patients with AML, whereas an acceptable proportion of primitive LTC-IC is spared. Moreover, despite the different kinetic and functional profile of mobilized and steady-state BM progenitors, we did not observe any difference in toxicity of antineoplastic agents on hematopoietic cells at different levels of differentiation. These data suggest that pharmacological strategies developed for eliminating minimal residual disease (MRD) from BM autografts can be effectively and safely applied to circulating stem cell harvests.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/análogos & derivados , Etoposídeo/administração & dosagem , Células-Tronco Hematopoéticas/patologia , Leucemia Mieloide Aguda/tratamento farmacológico , Mecloretamina/administração & dosagem , Neoplasia Residual/tratamento farmacológico , Antineoplásicos/administração & dosagem , Células da Medula Óssea/efeitos dos fármacos , Ciclofosfamida/administração & dosagem , Humanos , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/patologia , Células Tumorais Cultivadas/efeitos dos fármacos
16.
Bone Marrow Transplant ; 50(5): 673-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25642764

RESUMO

Incorporation of novel agents into auto-SCT for patients with multiple myeloma has led to improvement in their outcomes. However, the effects of new drugs, either single or combined, on PBSC mobilization have not been fully evaluated, particularly in phase 3 clinical studies. We analyzed the impact of two novel agent-based induction treatments in patients enrolled in the GIMEMA MMY-3006 study comparing bortezomib, thalidomide and dexamethasone (VTD) versus thalidomide and dexamethasone (TD) in preparation for double auto-SCT. Results showed that a short-term induction therapy with VTD did not adversely affect CD34(+) cell yields as compared with TD (9.75 vs 10.76 × 10(6) CD34(+) cells/kg, P=0.220). For poor mobilizers (<4 × 10(6) CD34(+) cells/kg), 5-year rates of time to progression (TTP), progression-free survival (PFS) and overall survival (OS) were significantly shorter than for successful mobilizers (TTP:17 vs 48%, P<0.0001; PFS: 16 vs 46%, P<0.0001; OS: 50 vs 80%, P<0.0001). These differences were retained across patients randomized to the TD arm; conversely, no differences in outcomes were seen in patients treated with VTD, irrespective of the number of harvested CD34(+) cells. The number of collected PBSCs predicted better outcomes after auto-SCT and VTD overcame the negative impact of a poor stem cell mobilization.


Assuntos
Bortezomib/administração & dosagem , Dexametasona/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico , Talidomida/administração & dosagem , Autoenxertos , Feminino , Humanos , Quimioterapia de Indução/métodos , Masculino , Pessoa de Meia-Idade
17.
FEBS Lett ; 492(3): 238-41, 2001 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-11257501

RESUMO

Wild-type bovine and yeast tRNA(Trp) are efficiently aminoacylated by tryptophanyl-tRNA synthetase both from beef and from yeast. Upon loss of modified bases in the synthetic transcripts, mammalian tRNA(Trp) retains the double recognition by the two synthetases, while yeast tRNA(Trp) loses its substrate properties for the bovine enzyme and is recognised only by the cognate synthetase. By testing chimeric bovine-yeast transcripts with tryptophanyl-tRNA synthetase purified from beef pancreas, the nucleotides responsible for the loss of charging of the synthetic yeast transcript have been localised in the anticodon arm. A complete loss of charging akin to that observed with the yeast transcript requires substitution in the bovine backbone of G37 in the anticodon loop with yeast A37 and of C28-G42 in the anticodon stem with yeast U28-A42. Since A37 does not prevent aminoacylation of the wild-type yeast tRNA(Trp) by the beef enzyme, a negative combination apparently emerges in the synthetic transcript after unmasking of U28 by loss of pseudourydilation.


Assuntos
RNA de Transferência de Triptofano/metabolismo , Triptofano-tRNA Ligase/metabolismo , Adenina/química , Animais , Sequência de Bases , Bovinos , Cinética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA de Transferência de Triptofano/química , Saccharomyces cerevisiae/genética , Especificidade da Espécie , Especificidade por Substrato , Uridina/química
18.
Transplantation ; 48(1): 119-22, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2787552

RESUMO

We report on the preparation of an antibody-conjugated enzyme consisting of xanthine oxidase, a free-radical-producing enzyme, linked to the 62B1 monoclonal antibody, which recognizes the last steps of differentiation of B cell lineage (plasma cell and hairy cells). The conjugate specifically kills target cells, retaining both enzymic and immunological properties, without any damage to normal myeloid clonogenic efficiency. The model is suitable for ex vivo bone marrow purging in multiple myeloma patients.


Assuntos
Anticorpos Monoclonais/toxicidade , Citotoxicidade Imunológica , Imunotoxinas/toxicidade , Plasmócitos/imunologia , Xantina Oxidase/toxicidade , Animais , Medula Óssea/imunologia , Catalase/toxicidade , Linhagem Celular , Células-Tronco Hematopoéticas/imunologia , Humanos , Hipoxantina , Hipoxantinas/toxicidade , Cinética , Camundongos , Superóxido Dismutase/toxicidade
19.
Biomaterials ; 25(2): 315-25, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14585719

RESUMO

Microporous materials have been produced by gradual precipitation from solutions of poly(epsilon-caprolactone) (PCL) in acetone induced by solvent extraction across a semi-permeable PCL membrane which is formed in situ at the polymer solution/non-solvent interface. Microparticulates of hydroxyapatite and inulin polysaccharide, respectively, were incorporated in precipitation cast PCL matrices to illustrate potential applications in hard tissue repair and macromolecular drug release. Microporous PCL and HA filled PCL materials were found to provide a favourable surface for attachment and growth of primary human osteoblasts in cell culture. The in vitro degradation characteristics of microporous PCL and inulin/PCL materials in PBS at 37 degrees C were monitored over 45 months. Microporous PCL demonstrated zero weight loss, minor changes in molecular weight characteristics and a fairly constant indentation resistance of around 1 MN/m2. Inulin-loaded PCL materials exhibited a total weight loss of approximately 17% after 12 months in PBS. The indentation resistance decreased by 50% from an initial value of 28 MN/m2 in the first 2 months and then remained stable. Precipitation cast materials based on PCL are expected to be useful for formulating long-term, controlled release devices for bioactive molecules such as growth factors and hormones and extended-residence supports for cell growth and tissue development.


Assuntos
Sistemas de Liberação de Medicamentos , Poliésteres/síntese química , Engenharia Tecidual , Substitutos Ósseos/síntese química , Substitutos Ósseos/metabolismo , Precipitação Química , Temperatura Alta , Humanos , Microscopia Eletrônica de Varredura , Osteoblastos/metabolismo , Poliésteres/metabolismo
20.
Bone Marrow Transplant ; 13(5): 577-81, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8054910

RESUMO

The toxicity of the conditioning regimen high-dose busulfan (BU) 16 mg/kg followed by cyclophosphamide (CY) 200 mg/kg has been analysed in 60 adult patients (mean age 36 +/- 9 years) with haematological malignancies, a third of whom had advanced disease, all received the graft from fully HLA-identical siblings. Significant nausea and vomiting were rare during BU administration but occurred in 44% of the patients with CY. Severe mucositis occurred in 30% of patients. Haemorrhagic cystitis occurred in 16% of patients; interstitial pneumonia occurred in 3 patients and was fatal in one. Veno-occlusive disease of the liver occurred in 2 patients and was fatal in one: however, increase of bilirubin of at least twice the baseline value and/or isolated weight gain > 5% of pre-transplant value occurred in 28% of patients. These signs of liver toxicity disappeared in all patients after appropriate therapy. Normalisation of bilirubin levels took twice as long as normalisation of body weight: median 35 and 18 days, respectively. Hyperpigmentation of the skin, mainly involving flexural and pressure areas, occurred in 47% of patients and was manageable topically. Eight patients died of relapsed disease; 15 died of transplant complications but in six the original malignancy persisted or had recurred at the time of death. Overall transplant-related mortality was 15%. We conclude that the toxicity of this regimen has not been high, with the liver being the most seriously affected organ. A longer follow-up is necessary to assess long-term consequences.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Transplante de Medula Óssea , Bussulfano/efeitos adversos , Ciclofosfamida/efeitos adversos , Leucemia/terapia , Mieloma Múltiplo/terapia , Adulto , Bussulfano/administração & dosagem , Ciclofosfamida/administração & dosagem , Feminino , Hepatopatia Veno-Oclusiva/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo
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