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1.
Helminthologia ; 61(1): 85-98, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38659464

RESUMO

A general limitation of ecological investigations based on nematodes is related to the difficult and time-consuming taxonomic identification of species. Therefore, nematologists are investing many efforts to develop alternative approaches as proxies applicable in biomonitoring assessment. Recently, an alternative method that combines morpho-functional traits was proposed for detecting assemblage changes of marine nematodes. In view of the promising results, it was tested the same approach to document taxonomic structure changes of soil free-living and plant parasitic nematodes. Specifically, this attempt was carried out using three data sets that include studies from various European regions and different types of ecosystems: forests, grasslands and maize crops. Multivariate statistical analysis revealed that the simple combination of the four traits (i.e., buccal cavity cuticularization occurrence, amphideal fovea size and shape, morphology of the cuticle and pharynx) in a single code number perfectly mirrors the taxonomic structure trends of the nematode assemblage at genus level. Therefore, we predict that similar results can be also obtained by directly encoding nematode specimens with the selected traits and we point to new important advances if this procedure can be coupled with advanced machine learning.

3.
Drug Alcohol Depend ; 225: 108847, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34182375

RESUMO

BACKGROUND: Alcohol consumption is responsible for a significant number of road fatalities. To contrast this phenomenon, a more responsible attitude to the wine consumption, especially among young, inexperienced drivers prone to risky behaviour on the road must be promoted. METHOD: This is a simplified single-blind, placebo-controlled experiment aimed at evaluating 44 young drivers monitored during a driving simulation following the consumption of natural and conventional wines, with a reference blood alcohol concentration (BAC) of 0.5 g/l. Two hypotheses are tested: (1) the legal consumption of wine has no significant impact on young drivers' performance in both ordinary and unusual road events; (2) natural and conventional wines are expected to produce negligible and acceptable impairments in young drivers the same BAC. Two reference groups (BAC = 0 g/l), one a placebo-controlled group with drivers treated with a dealcoholized wine, were included. RESULTS AND CONCLUSIONS: Significant differences between the groups in terms of perception and reaction times (PRT) to visual and auditory stimuli, and to speeding were observed, with young drivers treated with conventional wine displaying more aggressive behaviours. In contrast, participants treated with natural wine showed PRT which were not significantly different from those belonging to control groups. The gaze attention levels of wine treated drivers were found to be dose dependant, with young drivers of the two control groups and those of the treated ones with BAC < 0.3 g/l able to focus on wider area ahead and, thereby, collect more information from the road environment.


Assuntos
Condução de Veículo , Vinho , Acidentes de Trânsito/prevenção & controle , Consumo de Bebidas Alcoólicas/epidemiologia , Concentração Alcoólica no Sangue , Humanos , Método Simples-Cego
5.
Accid Anal Prev ; 139: 105487, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32135336

RESUMO

A passing maneuver allows drivers to maintain their desired speed on two-lane highways. However, it entails a high risk of collision with vehicles travelling in the opposite direction. Investigating drivers' behavior while performing passing maneuvers could provide helpful information on the factors that influence this process. Driving simulators have become important tools for driving behavior research studies as they are safe, facilitate the controlled use of experimental variables, and generate detailed output data. It remains to be seen whether simulator results can be considered representative of real-life driving conditions. With respect to passing maneuvers, no study has made a comprehensive and direct comparison between drivers' passing behavior in the field and driver behavior observed in a simulated environment. In this validation study, a fixed-base interactive simulator was used to collect data from fifty-four participants (eighteen Iranians and thirty-six Italians) involved in several traffic scenarios on a two-lane rural highway segment (obtained by varying the speed of opposing vehicles, lead vehicles and headways in the opposite direction). A 3D model and its environmental characteristics were realized from the real segment which had previously been surveyed with drones to collect videos and derive data on real passing maneuvers. The results for the two-sided K-S test revealed no statistically significant difference in the accepted gap, effective accepted gap, perception reaction time, and time to collision variables between the field and the simulator at the 95 % confidence level. However, when conducting a one-sided K-S test, some statistical directional differences were found in the cases of the accepted gap and perception reaction time variables, which exhibited lower values in the field compared to the simulator again at the 95 % confidence level. Although the passing duration was statistically higher in the simulator than in the field, the shape of the two distributions was not statistically different. Analysis showed that differences in the passing duration are due to the lower passing vehicle speed and lower speed difference with the simulator than in the field, which are caused by truncating headways in the subject direction in the simulator. The cultural background of participants did not result in any discernible difference in passing behavior. The results would support a more extensive use of driving simulators in future passing behavior studies.


Assuntos
Condução de Veículo/psicologia , Simulação por Computador/normas , Acidentes de Trânsito/prevenção & controle , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Medição de Risco , Adulto Jovem
6.
Accid Anal Prev ; 131: 200-212, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31306834

RESUMO

The available sight distance (ASD) is the maximum length of the roadway ahead visible to the driver. It is a fundamental factor in road geometry principles and is used by road designers to ensure safe driving conditions. However, designers do not know how a specific ASD may affect the longitudinal and transversal behavior of drivers engaged in negotiating curves. This paper focuses on analyzing driver longitudinal behavior along rural highways curves with limited visibility. A number of virtual sight condition scenarios were recreated and tested in the driving simulator. Three tracks were designed with various combinations of radii and sight obstructions (a continuous wall) along the roadside located at various offsets from the lane centerline, combinations which resulted with a minimum ASD of 56.6 m. Roadside factors capable of influencing the risk perception of drivers (e.g., traffic barriers, posted speed limit signs, vegetation) were all excluded from the simulations. Results indicate that speed and trajectory dispersion from the lane centerline depend linearly on ASD in the investigated range of curve radii (from 120 to 430 m). In general, when ASD increases, so does speed and the trajectories tend to be less dispersed around the lane centerline. As a result, in safety terms, any variation in ASD will have the polar opposite effect on safety related parameters. Furthermore, different curves with similar ASD values resulted in different speed and lateral control behaviors. Analysis from ANOVA support the same findings; in addition, radius, curve direction, and distance from trajectory to sight obstruction have been identified as significant independent parameters. Road designers should adjust the ASD and these parameters when seeking to encourage drivers to adopt appropriate behaviors. To optimize safe driving conditions, ASD should be designed so that it is slightly greater than the required sight distance, since excessive ASD values may encourage drivers to drive at inappropriate speeds.


Assuntos
Condução de Veículo , Ambiente Construído , Tempo de Reação/fisiologia , Acidentes de Trânsito/prevenção & controle , Simulação por Computador , Feminino , Humanos , Masculino , População Rural , Percepção Visual/fisiologia
7.
Dig Liver Dis ; 39(10): 943-51, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17692581

RESUMO

BACKGROUND/AIM: Controversial experimental observations suggest that granulocyte colony stimulating-factor may promote hepatic regeneration after hepatectomy and chemical injury either by directly stimulating adult liver cells or facilitating the mobilization of bone marrow cells and their homing to the liver. We investigated whether different schedules of granulocyte colony stimulating-factor administration protect against experimental acute liver injury. METHODS: Acute liver injury was induced in Sprague-Dawley fed rats by injecting a single intraperitoneal dose of carbon tetrachloride. Recombinant human granulocyte colony stimulating-factor or vehicle was given daily after intoxication (4 days) or before (7 days) and after carbon tetrachloride administration. Liver injury and regeneration were assessed 2 and 4 days after damage. Bone marrow cells mobilization was evaluated by the white blood cell count and the assessment of circulating clonogenic haematopoietic progenitors (colony forming unit-cells). RESULTS: In this experimental model, although granulocyte colony stimulating-factor induced the significant mobilization of colony forming unit-cells, the study cytokine had no effect on liver injury (serum alanine amino transaminase level and necrotic index) and liver regeneration (mitotic index and bromodeoxyuridine incorporation), regardless of the administration schedule. CONCLUSIONS: This study does not support the conclusion that: (1) granulocyte colony stimulating-factor exerts a protective effect against toxic-induced, non-lethal acute liver injury and (2) promotes hepatocyte regeneration.


Assuntos
Fatores Estimuladores de Colônias/uso terapêutico , Falência Hepática Aguda/tratamento farmacológico , Animais , Tetracloreto de Carbono/toxicidade , Modelos Animais de Doenças , Citometria por Imagem , Imuno-Histoquímica , Contagem de Leucócitos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/patologia , Regeneração Hepática/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes , Resultado do Tratamento
8.
Leukemia ; 16(9): 1773-81, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12200693

RESUMO

Although the transcription factor nuclear factor-erythroid 2 (NF-E2) is known to be functionally linked to the megakaryocytic lineage, little is known about its role in malignant megakaryocytes. We used real-time RT-PCR and Western blotting to investigate expression of NF-E2 and its partner, MafG, in CD34-derived normal (five cases) and malignant megakaryocytes from essential thrombocythemia (ET) patients (eight cases) and in megakaryoblastic cell lines. We also quantitated the mRNA of the thromboxane synthase (TXS) gene, which is directly regulated by NF-E2. Although real-time RT-PCR showed that both a and f NF-E2 isoforms were significantly reduced with respect to the normal counterpart both in ET megakaryocytes and in cell lines (P < or = 0.01), western blotting revealed decreased NF-E2 protein expression only in the latter. However, both the NF-E2a/MafG mRNA ratio (P < or = 0.01) and TXS (P< or = 0.01) mRNA expression were significantly reduced in megakaryocytes from ET patients and cell lines with respect to healthy subjects. These two findings provide strong indirect evidence of altered activity of the a isoform of NF-E2 in malignant megakaryocytes, raising the possibility that NF-E2 could play a role in megakaryocyte transformation.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Megacariócitos/metabolismo , Trombocitopenia/metabolismo , Trombocitose/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Adulto , Antígenos CD34/metabolismo , Western Blotting , Medula Óssea/química , Estudos de Casos e Controles , Primers do DNA/química , Fatores de Ligação de DNA Eritroide Específicos , Eritropoese , Feminino , Citometria de Fluxo , Humanos , Fator de Transcrição MafG , Masculino , Pessoa de Meia-Idade , Fator de Transcrição NF-E2 , Subunidade p45 do Fator de Transcrição NF-E2 , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Trombocitopenia/genética , Trombocitopenia/patologia , Tromboxano-A Sintase/genética , Tromboxano-A Sintase/metabolismo , Células Tumorais Cultivadas
9.
Exp Hematol ; 15(6): 679-84, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3496235

RESUMO

Conditioned medium from a T-lymphoblastic cell line (Mo) contains a number of well-characterized hemopoietins. In this paper we demonstrate that Mo cells also release a factor(s) able to stimulate the growth and the differentiation of megakaryocytic progenitors into large-size pure megakaryocytic colonies in plasma clot cultures. Comparison with other sources of human-active hemopoietins shows that Mo-conditioned medium performs better than others, especially for the megakaryocytic lineage. The factor(s) shows strong similarities with human Meg-CSF obtained from a thrombocytopenic patient's plasma, and is distinguishable from the other hemopoietins present in the medium.


Assuntos
Megacariócitos/efeitos dos fármacos , Biossíntese de Proteínas , Proteínas , Linfócitos T/metabolismo , Células da Medula Óssea , Linhagem Celular , Ensaio de Unidades Formadoras de Colônias , Relação Dose-Resposta a Droga , Proteínas Ligadas por GPI , Humanos , Interleucina-3/fisiologia , Leucemia de Células Pilosas/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Cooperação Linfocítica , Megacariócitos/citologia , Glicoproteínas de Membrana , Mesotelina , Peso Molecular , Fito-Hemaglutininas/farmacologia , Púrpura Trombocitopênica/patologia , Linfócitos T/classificação , Trombocitemia Essencial/patologia
10.
Exp Hematol ; 20(4): 512-6, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1533189

RESUMO

We studied human megakaryocytes to determine if they both expressed and synthesized Fc gamma and CD4 membrane receptors. The strategy employed relied on demonstration of receptor protein and mRNA in megakaryocytes present in freshly made marrow smears, or in megakaryocytes isolated from aspirated normal bone marrow by counterflow centrifugal elutriation. Protein was detected immunochemically, whereas mRNA was detected either by in situ hybridization, or by reverse transcription, polymerase chain reaction (RT-PCR). Using these methods CD4 and Fc gamma RII protein and mRNA were detected in most megakaryocytes. Fc gamma RI and Fc gamma RIII protein was not detected in these cells. Megakaryocytes were also cultured with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) to determine the effect of this growth factor on Fc gamma RII expression. As has been noted in cells of the monocyte-macrophage lineage, exposure to rhGM-CSF resulted in a significant increase in the level of megakaryocyte Fc gamma RII mRNA and protein. These observations are significant because they provide a physiologic basis for known viral trophism displayed by megakaryocytes. They are also of interest because they suggest that alternative portals exist for entry of human immunodeficiency virus (HIV-1) into megakaryocytes and that such infection may play a role in acquired immunodeficiency syndrome (AIDS)-related thrombocytopenia.


Assuntos
Antígenos de Diferenciação/metabolismo , Antígenos CD4/fisiologia , Megacariócitos/metabolismo , Receptores Fc/metabolismo , Anticorpos Monoclonais , Sequência de Bases , Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Oligonucleotídeos/química , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Receptores de IgG
11.
Exp Hematol ; 14(1): 72-4, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3510892

RESUMO

The procoagulant cellular activity (PCA) of human myeloid precursor cells was evaluated after fractionation of normal bone marrow cells over a discontinuous albumin density gradient. No PCA was documented in any of the six freshly isolated fractions (F1-F6); significant amounts of PCA were instead produced, after a 4-h endotoxin preincubation, in fractions F1 and F2, which, unlike the other fractions, contained up to 5% monocyte-macrophages. After removal of the latter by plastic adherence, the PCA was abolished. This study shows that PCA can be produced only by monocyte-macrophages upon endotoxin activation, while myeloid precursor cells, at all stages of differentiation, are incapable of PCA. The PCA demonstrated in some human acute myeloid leukemias, other than that of the monoblastic subgroup, appears therefore to be related to the neoplastic transformation rather than to a maturation arrest or to a toxemic stimulation.


Assuntos
Fatores de Coagulação Sanguínea/biossíntese , Células-Tronco Hematopoéticas/fisiologia , Diferenciação Celular , Fracionamento Celular , Endotoxinas/farmacologia , Humanos , Macrófagos/metabolismo , Monócitos/metabolismo , Salmonella enteritidis
12.
Exp Hematol ; 23(14): 1520-6, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8542941

RESUMO

We have recently reported that the hematologic recovery of patients with non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD) undergoing autologous bone marrow transplantation (BMT) is significantly faster when recombinant human interleukin-3 (rhIL-3) is combined with recombinant human granulocyte colony-stimulating factor (rhG-CSF) in comparison with patients receiving G-CSF alone. In this paper, we studied the kinetic response and concentration of BM progenitor cells of 17 patients with lymphoid malignancies submitted to autologous BMT and treated with the G-CSF/IL-3 combination. The results were compared with those of five lymphoma patients receiving the same pretransplant conditioning regimen followed by G-CSF alone. rhG-CSF was administered as a single subcutaneous (sc) injection at the dose of 5 micrograms/kg/d from day 1 after reinfusion of autologous stem cells; rhIL-3 was added from day 6 at the dose of 10 micrograms/kg/d sc (overlapping schedule). In both groups (G-CSF- and G-CSF/IL-3-treated patients), cytokine administration was discontinued when the absolute neutrophil count (ANC) was >0.5 x 10(9)/L of peripheral blood (PB) for 3 consecutive days. After treatment with the CSF combination, the percentage of marrow colony-forming units-granulocyte/macrophage (CFU-GM) and erythroid progenitors (BFU-E) in S phase of the cell cycle increased from 9.3 +/- 2% to 33.3 +/- 12% and from 14.6 +/- 3% to 35 +/- 6%, respectively (p < 0.05). Similarly, we observed an increased number of actively cycling megakaryocyte progenitors (CFU-MK and BFU-MK). Conversely, G-CSF augmented the proliferative rate of CFU-GM (22.6 +/- 0.6% compared to a baseline value of 11.5 +/- 3%; p < 0.05) but not of BFU-E, CFU-MK, or BFU-MK, and the increase of S-phase CFU-GM was significantly lower than that observed in the posttreatment samples of patients receiving IL-3 in addition to G-CSF. The frequency of hematopoietic precursors in the BM, expressed as the number of colonies formed per number of cells plated, was unchanged or slightly decreased in both groups of patients. Because of the increase in marrow cellularity, however, a significant augmentation of the absolute number of both CFU-GM (3605 +/- 712/mL BM vs. 2213 +/- 580/mL; p < 0.05) and BFU-E (4373 +/- 608/mL vs. 3027 +/- 516/mL; p < 0.05) was reported after treatment with G-CSF/IL-3 but not G-CSF alone. Similarly, administration of the cytokine combination resulted in a higher number of CD34+ cells/mL BM, and their concentration was significantly greater than that observed in the posttreatment samples of G-CSF patients. Finally, we investigated the responsiveness to CSFs, in vitro, of highly enriched CD34+ cells, collected after priming with G-CSF in vivo (i.e., after 5 days of G-CSF administration). Our results demonstrated that pretreatment with G-CSF modified the response of BM cells to subsequent stimulation with additional CSFs. The results presented in this paper indicate that in vivo administration of two cytokines increases the proliferative rate and concentration of BM progenitor cells to a greater degree than G-CSF alone. These results support the role of growth factor combinations for accelerating hematopoietic recovery after high-dose chemotherapy.


Assuntos
Células da Medula Óssea , Transplante de Medula Óssea , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Granulócitos/citologia , Células-Tronco Hematopoéticas/citologia , Divisão Celular , Ensaio de Unidades Formadoras de Colônias , Quimioterapia Combinada , Células Precursoras Eritroides/citologia , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Hematopoese , Doença de Hodgkin/terapia , Humanos , Interleucina-3/administração & dosagem , Interleucina-3/uso terapêutico , Contagem de Leucócitos , Linfoma não Hodgkin/terapia , Macrófagos/citologia , Megacariócitos/citologia , Neutrófilos , Proteínas Recombinantes/uso terapêutico , Transplante Autólogo
13.
Leukemia ; 29(6): 1344-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25801912

RESUMO

We investigated the influence of molecular status on disease characteristics and clinical outcome in young patients (⩽ 40 years) with World Health Organization (WHO)-defined essential thrombocythemia (ET) or early/prefibrotic primary myelofibrosis (early-PMF). Overall, 217 patients with ET (number 197) and early-PMF (number 20) were included in the analysis. Median follow-up time was 10.2 years. The cumulative incidence of thrombosis, hemorrhages and disease evolution into myelofibrosis/acute leukemia were 16.6%, 8.6% and 3% at 15 years, respectively. No differences were detectable between ET and early-PMF patients, although the latter cohort showed a trend for worse combined-event free survival (EFS). Mutation frequency were 61% for JAK2V617F, 25% for CALR and 1% for MPLW515K, and were comparable across WHO diagnosis; however, JAK2V617F allele burden was higher in the early-PMF group. Compared with JAK2V617F-positive patients, CALR-mutated patients displayed higher platelet count and lower hemoglobin level. CALR mutations significantly correlated with lower thrombotic risk (9.1% versus 21.7%, P = 0.04), longer survival (100% versus 96%, P = 0.05) and better combined-EFS (86% versus 71%, P = 0.02). However, non-type 1/type 2 CALR mutations ('minor' mutations) and abnormal karyotype were found to correlate with increased risk of disease evolution. At last contact, six patients had died; in five cases, the causes of death were related to the hematological disease and occurred at a median age of 64 years (range: 53-68 years). Twenty-eight patients (13%) were unmutated for JAK2, CALR and MPL: no event was registered in these 'triple-negative' patients.


Assuntos
Calreticulina/genética , Janus Quinase 2/genética , Mutação/genética , Mielofibrose Primária/genética , Mielofibrose Primária/mortalidade , Receptores de Trombopoetina/genética , Trombocitemia Essencial/genética , Trombocitemia Essencial/mortalidade , Adolescente , Adulto , Idoso , Estudos de Coortes , Análise Citogenética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Adulto Jovem
14.
AIDS ; 7(6): 823-7, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8363758

RESUMO

OBJECTIVE: To assess the efficacy and the mechanism of action of alpha-interferon (alpha-IFN) in the treatment of HIV-related thrombocytopenia. METHODS: Thirteen HIV-positive subjects [nine men and four women with severe thrombocytopenia (platelets, < or = 30 x 10(9)/l)] were treated with alpha-IFN 2b alone at a dose of 3 x 10(6) U three times a week for 5 weeks. Haematological parameters, platelet kinetic and bone-marrow myeloid progenitor cultures [megakaryocyte colony-forming units (CFU-MK); granulocyte macrophage CFU (CFU-GM) and erythroid burst-forming units (BFU-E)] were evaluated before and after treatment in responsive subjects. RESULTS: Seven out of 13 subjects showed a partial response (platelets, 50-149 x 10(9)/l) after alpha-IFN 2b therapy. Platelet survival as evaluated by 111In-oxine significantly increased, while platelet turnover showed a slight but not statistically significant increase after treatment. The growth of bone-marrow myeloid progenitor cells decreased after alpha-IFN 2b therapy, again without statistical significance. CONCLUSION: alpha-IFN 2b may increase the platelet count in HIV-positive subjects with severe symptomatic thrombocytopenia by prolonging platelet survival. The immunomodulatory and antiviral action of this drug may be responsible for prolonged platelet survival.


Assuntos
Complexo Relacionado com a AIDS/complicações , Interferon-alfa/uso terapêutico , Trombocitopenia/terapia , Complexo Relacionado com a AIDS/sangue , Adulto , Doenças Autoimunes/sangue , Doenças Autoimunes/complicações , Doenças Autoimunes/terapia , Sobrevivência Celular , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Avaliação de Medicamentos , Células Precursoras Eritroides/efeitos dos fármacos , Células Precursoras Eritroides/patologia , Eritropoetina/farmacologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Hematopoese/efeitos dos fármacos , Humanos , Interferon alfa-2 , Interleucina-3/farmacologia , Masculino , Megacariócitos/efeitos dos fármacos , Megacariócitos/patologia , Contagem de Plaquetas/efeitos dos fármacos , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/complicações , Púrpura Trombocitopênica Idiopática/terapia , Proteínas Recombinantes/farmacologia , Trombocitopenia/sangue , Trombocitopenia/complicações , Trombocitopenia/patologia
15.
Mech Ageing Dev ; 122(8): 823-33, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11337011

RESUMO

We have investigated the mitochondrial energy state in human platelets of young (19-30 years old) and aged individuals (65-87 years old) exploiting the Pasteur effect, i.e. stimulation of lactate production by incubation of the purified platelets with the mitochondrial respiratory chain inhibitor, antimycin A. This assay allows the determination of mitochondrial function with respect to glycolysis, and the ratio of mitochondrial adenosine triphosphate (ATP) to glycolytic ATP. A significant increase of basal, non-stimulated lactate production and decrease of the stimulation by antimycin A were observed in the older individuals, suggesting that the impairment of oxidative phosphorylation detectable in post-mitotic tissues of aged individuals can be observed also in easily collectable blood cells.


Assuntos
Envelhecimento/fisiologia , Plaquetas/fisiologia , Mitocôndrias/fisiologia , Trifosfato de Adenosina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Antimicina A/farmacologia , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Células Cultivadas , Feminino , Glucose/metabolismo , Humanos , Ácido Láctico/biossíntese , Masculino
16.
Thromb Haemost ; 64(1): 11-6, 1990 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-2274915

RESUMO

Blast cell extracts from patients with acute non lymphoid leukemia (ANLL) express cancer procoagulant (CP). This factor X (FX) activator is distinct from tissue factor (TF) in that it does not require factor VII (FVII) to trigger blood coagulation, it acts as a cysteine proteinase and is not present in normal mononuclear cells. To assess whether there is any relationship between the presence of CP and the status of the disease, ANLL patients have been studied at diagnosis, during remission, at relapse. The procoagulant activity in either the presence or absence of F VII and sensitivity to cysteine proteinase inhibitors were tested on cell extracts. Immunoreactivity was explored with an anti-CP polyclonal antibody. Data obtained in 91 newly-diagnosed ANLL patients (subtypes M1 to M5, FAB classification) confirmed the presence of CP in M1 to M4 groups (mean +/- SE FVII-independent activity: M1 = 2.1 +/- 0.7 unit/mg; M2 = 5.7 +/- 1.7 unit/mg; M3 = 31.5 +/- 8 unit/mg; M4 = 1.6 +/- 1.2 unit/mg); CP was absent in the M5 type. In eight patients analyzed in a subsequent phase of partial remission, specific activity had dropped from 26.9 +/- 7.8 to 10.5 +/- 4.0 unit/mg. Activity was virtually absent (0-0.05 unit/mg) in the bone marrow of 37 patients studied at complete remission. Bone marrow samples from six subjects tested at different intervals after complete remission were repeatedly negative for CP but became positive 2 to 5 months before relapse. Upon relapse, the FVII independent activity rose to 24.2 +/- 8.2 unit/mg.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fatores de Coagulação Sanguínea/análise , Ensaios Enzimáticos Clínicos , Cisteína Endopeptidases/análise , Leucemia Mieloide Aguda/diagnóstico , Proteínas de Neoplasias , Adolescente , Adulto , Idoso , Crise Blástica/patologia , Criança , Pré-Escolar , Inibidores de Cisteína Proteinase/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão/métodos
17.
Bone Marrow Transplant ; 22 Suppl 5: S47-50, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9989890

RESUMO

We review here the functional and kinetic characteristics of highly purified hematopoietic CD34+ mobilized into peripheral blood (PB) by granulocyte colony-stimulating factor (G-CSF) with or without chemotherapy for autologous or allogeneic transplantation. Circulating CD34+ cells were evaluated for their colony-forming capacity and trilineage proliferative response to selected recombinant human (rh) CSF in vitro, and the content of very primitive long-term culture initiating cells (LTC-IC). In addition, the cycling status of PB CD34+ cells, including committed clonogenic progenitor cells and the more immature LTC-IC, was determined by the cytosine arabinoside (Ara-C) suicide test and the acridine orange (AO) flow cytometric technique. By comparison, bone marrow (BM) CD34+ cells from the same individuals were studied under steady-state conditions and during G-CSF administration. Clonogenic assays in methylcellulose showed the same frequency of colony-forming unit cells (CFU-C) when PB primed-CD34+ cells and BM cells were stimulated with phytohemagglutinin-lymphocyte-conditioned medium (PHA-LCM). However, mobilized CD34+ cells were significantly more responsive than their steady-state BM counterparts to interleukin-3 (IL-3) and stem cell factor (SCF) combined with G-CSF or IL-3 in the presence of erythropoietin (Epo). Conversely, circulating and BM megakaryocyte precursors (CFU-MK) showed the same clonogenic efficiency in response to IL-3, GM-CSF and IL-3, IL-6 and Epo. Interestingly, very few CD34+ cells expressed the Mpl receptor and this finding resulted in the lower proliferative response of mobilized CFU-MK to the Mpl-ligand (megakaryocyte growth and development factor; MGDF), as compared to BM cells. After 5 weeks of liquid culture supported by the engineered murine stromal cell line M2-10B4 to produce G-CSF and IL-3, we reported a similar frequency of LTC-IC in PB and steady-state BM. Kinetic studies on PB and BM CD34+ cells, including LTC-IC, showed the low number of circulating progenitor cells in S and G2M phase whereas simultaneous DNA/RNA analysis and the Ara-C suicide assay demonstrated that the majority of PB CD34+ cells and LTC-IC are not quiescent (ie in G0 phase) being in G1 phase. Moreover, G-CSF administration prevented apoptosis in a small but significant proportion of mobilized CD34+ cells. Thus, our results indicate that mobilized and BM CD34+ cells can be considered equivalent for the frequency of both committed and more immature hematopoietic progenitor cells, although they show different kinetic and functional profiles. A further set of experiments indicated that G-CSF treatment did not alter the alloantigen presenting function of CD34+ cells which was mainly mediated by the upregulation of costimulatory molecules upon coincubation with allogeneic T cells. Taken together, these findings should allow a better understanding of PBSC transplantation.


Assuntos
Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/imunologia , Adulto , Apresentação de Antígeno/fisiologia , Antígenos CD34/análise , Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Contagem de Células/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Fatores Estimuladores de Colônias/farmacologia , Citarabina/farmacologia , Citometria de Fluxo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Proteínas Recombinantes/farmacologia , Fatores de Tempo
18.
Bone Marrow Transplant ; 12(3): 253-9, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8241985

RESUMO

Severe thrombotic alterations, such as veno-occlusive disease of the liver, may occur in the early phase following high-dose chemoradiotherapy and BMT. In this study, performed in patients with hematological malignancies subjected to allogeneic (10 cases) and autologous (20 cases) BMT, we have monitored laboratory hemostatic parameters to better understand the pathogenetic mechanism of thrombosis and particularly of veno-occlusive disease. Prothrombin time, activated partial thromboplastin time, plasma fibrinogen, markers of hypercoagulability (thrombin-antithrombin complex and prothrombin fragment F1+2); natural anticoagulants (protein C, protein S and antithrombin) together with fibrinolytic parameters (plasminogen, alpha 2-antiplasmin, tissue-plasminogen activator, plasminogen activator inhibitor and D-dimer) were assessed before transplant, on day 0 and weekly for 1 month thereafter. A hypercoagulability state, not related to an impairment of the anticoagulant and fibrinolytic systems, was documented before and after autologous and allogeneic transplant. Two patients developed veno-occlusive disease: they did not show any difference from the other patients before transplant while they presented a decrease of the natural anticoagulants along with altered fibrinolytic parameters only at the clinical onset of veno-occlusive disease. In conclusion, in this study a state of marked hypercoagulability was documented in BMT patients and the hemostatic laboratory parameters evaluated were not able to predict the occurrence of the thrombotic complications.


Assuntos
Transtornos da Coagulação Sanguínea/complicações , Transplante de Medula Óssea/efeitos adversos , Hepatopatia Veno-Oclusiva/etiologia , Leucemia/sangue , Linfoma/sangue , Mieloma Múltiplo/sangue , Antitrombina III/análise , Testes de Coagulação Sanguínea , Purging da Medula Óssea , Suscetibilidade a Doenças , Feminino , Humanos , Imunossupressores/uso terapêutico , Leucemia/cirurgia , Linfoma/cirurgia , Masculino , Mieloma Múltiplo/cirurgia , Fragmentos de Peptídeos/análise , Peptídeo Hidrolases/análise , Protrombina/análise , Trombose/etiologia , Transplante Autólogo , Transplante Homólogo
19.
Bone Marrow Transplant ; 17(2): 277-80, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8640179

RESUMO

Thrombotic complications may occur early after marrow transplantation and many data suggest that endothelial injury plays a pivotal role in their pathogenesis. Since plasma thrombomodulin and P-selectin are thought to be of value as markers of vascular endothelial cell membrane injury, we investigated their plasma concentration in bone marrow transplant patients aiming better to clarify the degree of endothelial involvement. Plasma thrombomodulin and P-selectin were monitored in 25 patients without thrombotic complications before transplant, on day 0 and weekly for 1 month thereafter, while in three patients who developed VOD monitoring continued until day +52. These proteins were in the normal range in all the uncomplicated patients and in two with reversible VOD, while they were always very high in the only patient who developed very severe and lethal VOD. In conclusion, we suggest that endothelial activation/damage occurs rarely in the course of BMT for hematological malignancies; we were able to document endothelial injury in only one patient with very severe thrombotic complication.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Endotélio Vascular/lesões , Hepatopatia Veno-Oclusiva/etiologia , Adolescente , Adulto , Biomarcadores , Feminino , Hepatopatia Veno-Oclusiva/sangue , Humanos , Leucemia/terapia , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Selectina-P/sangue , Trombomodulina/análise , Trombose/sangue , Trombose/etiologia
20.
Bone Marrow Transplant ; 24(11): 1191-4, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10642807

RESUMO

Thrombocytopoiesis of 21 multiple myeloma patients undergoing single or double transplant regimen was characterized by measuring the level of reticulated platelets and plasma glycocalicin. Since reticulated platelets are an index of thrombopoietic activity and glycocalicin plasma values are related to platelet damage and turnover, it may be possible to perform a novel type of analysis of the thrombopoietic compartment during the mobilizing regimen and during transplant-related chemotherapy. Patients underwent mobilizing therapy and first transplant. Some randomized patients also underwent a second transplant with mobilized peripheral blood stem cells. The results show that the percentage of reticulated platelets decreased after therapy and then gradually increased in the recovery phase either during first or second transplant. By contrast, the percentage of reticulated platelets increased until day +8 and then gradually decreased during the mobilizing regimen. The glycocalicin index (glycocalicin plasma value normalized for the individual platelet count) increased significantly both during the course of mobilization and after transplant-related chemotherapy when the platelet number was at its nadir. However, the glycocalicin index was more elevated after transplant-related chemotherapy than after the mobilizing regimen. Our findings suggest that chemotherapy-related thrombocytopenia may be due to a dual mechanism: thrombocytopenia results from decreased platelet production in addition to increased platelet damage and possible destruction.


Assuntos
Plaquetas/química , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Reticulócitos/efeitos dos fármacos , Trombocitopenia/terapia , Transplante Autólogo/efeitos adversos , Antígenos CD34/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Comportamental , Biomarcadores/sangue , Bussulfano/administração & dosagem , Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Doxorrubicina/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Melfalan/administração & dosagem , Mieloma Múltiplo/terapia , Inibidores da Agregação Plaquetária/farmacologia , Contagem de Plaquetas/efeitos dos fármacos , RNA/sangue , RNA/efeitos dos fármacos , Trombocitopenia/etiologia , Vincristina/administração & dosagem
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