Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Gen Comp Endocrinol ; 273: 184-191, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29990493

RESUMO

Studies of birds have greatly advanced our understanding of how testosterone modulates complex phenotypes, specifically its role in mediating male reproductive and associated behaviors. Yet most of the foundational studies have been limited to northern latitude breeding species despite the fact that they represent only a small fraction of worldwide avian diversity. In contrast, phylogenetic, life-history, and mating system diversity all reach their apex in neotropical avifauna and yet these birds, along with more southern latitude species, remain very poorly understood from an endocrine perspective. Despite the relatively limited previous work on taxa breeding in Central and South America, empirical findings have had a disproportionately large impact on our understanding of testosterone's role in everything from geographic variation to behavioral roles and neuroplasticity. Here, we synthesize how studies of neotropical breeding avifauna have advanced our understanding of how testosterone's actions can and are associated with the broad patterns of phenotypic diversity that we see in birds. In addition, we outline how these studies can be used individually or in a comparative context to address fundamental questions about the environmental endocrinology of testosterone and to understand the diversity of roles that testosterone plays in mediating behavioral variation, reproductive strategies, and associated life-history trade-offs.


Assuntos
Aves/metabolismo , Endocrinologia , Meio Ambiente , Testosterona/metabolismo , Clima Tropical , Animais , Feminino , Masculino , Plasticidade Neuronal
2.
Biol Blood Marrow Transplant ; 19(6): 904-11, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23416854

RESUMO

Manifestations of and risk factors for graft-versus-host disease (GVHD) after double-unit cord blood transplantation (DCBT) are not firmly established. We evaluated 115 DCBT recipients (median age, 37 years) who underwent transplantation for hematologic malignancies with myeloablative or nonmyeloablative conditioning and calcineurin inhibitor/mycophenolate mofetil immunosuppression. Incidence of day 180 grades II to IV and III to IV acute GVHD (aGVHD) were 53% (95% confidence interval, 44 to 62) and 23% (95% confidence interval, 15 to 31), respectively, with a median onset of 40 days (range, 14 to 169). Eighty percent of patients with grades II to IV aGVHD had gut involvement, and 79% and 85% had day 28 treatment responses to systemic corticosteroids or budesonide, respectively. Of 89 engrafted patients cancer-free at day 100, 54% subsequently had active GVHD, with 79% of those affected having persistent or recurrent aGVHD or overlap syndrome. Late GVHD in the form of classic chronic GVHD was uncommon. Notably, grades III to IV aGVHD incidence was lower if the engrafting unit human leukocyte antigen (HLA)-A, -B, -DRB1 allele match was >4/6 to the recipient (hazard ratio, 0.385; P = .031), whereas engrafting unit infused nucleated cell dose and unit-to-unit HLA match were not significant. GVHD after DCBT was common in our study, predominantly affected the gut, and had a high therapy response, and late GVHD frequently had acute features. Our findings support the consideration of HLA- A,-B,-DRB1 allele donor-recipient (but not unit-unit) HLA match in unit selection, a practice change in the field. Moreover, new prophylaxis strategies that target the gastrointestinal tract are needed.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Trato Gastrointestinal/imunologia , Doença Enxerto-Hospedeiro/terapia , Antígenos HLA/imunologia , Neoplasias Hematológicas/terapia , Agonistas Mieloablativos/uso terapêutico , Condicionamento Pré-Transplante , Adolescente , Corticosteroides/uso terapêutico , Adulto , Idoso , Budesonida/uso terapêutico , Calcineurina/metabolismo , Inibidores de Calcineurina , Criança , Pré-Escolar , Inibidores Enzimáticos/uso terapêutico , Feminino , Trato Gastrointestinal/patologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/patologia , Teste de Histocompatibilidade , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Índice de Gravidade de Doença , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento
3.
Eur Respir J ; 39(3): 691-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21778169

RESUMO

Fundoplication may improve survival after lung transplantation. Little is known about the effects of fundoplication on quality of life in these patients. The aim of this study was to assess the safety of fundoplication in lung transplant recipients and its effects on quality of life. Between June 1, 2008 and December 31, 2010, a prospective study of lung transplant recipients undergoing fundoplication was undertaken. Quality of life was assessed before and after surgery. Body mass index (BMI) and pulmonary function were followed up. 16 patients, mean ± sd age 38 ± 11.9 yrs, underwent laparoscopic Nissen fundoplication. There was no peri-operative mortality or major complications. Mean ± SD hospital stay was 2.6 ± 0.9 days. 15 out of 16 patients were satisfied with the results of surgery post fundoplication. There was a significant improvement in reflux symptom index and DeMeester questionnaires and gastrointestinal quality of life index scores at 6 months. Mean BMI decreased significantly after fundoplication (p = 0.01). Patients operated on for deteriorating lung function had a statistically significant decrease in the rate of lung function decline after fundoplication (p = 0.008). Laparoscopic fundoplication is safe in selected lung transplant recipients. Patient benefit is suggested by improved symptoms and satisfaction. This procedure is acceptable, improves quality of life and may reduce deterioration of lung function.


Assuntos
Fundoplicatura , Refluxo Gastroesofágico/cirurgia , Transplante de Pulmão , Qualidade de Vida , Adulto , Índice de Massa Corporal , Feminino , Humanos , Laparoscopia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Testes de Função Respiratória , Inquéritos e Questionários , Resultado do Tratamento
4.
J Exp Med ; 171(5): 1697-704, 1990 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-2139699

RESUMO

We have characterized a child with a severe combined immunodeficiency disease syndrome with increased numbers, but a normal distribution, of CD3+ T cells. This patient's immunological defect appears to be attributable to a selective deficiency in T cell production of IL-2, which may reflect a subtle abnormality in the IL-2 gene locus or a defect in a regulatory factor necessary for IL-2 transcription. The increased numbers of phenotypically normal T cells in this patient suggest that alternative pathways of T cell development exist in man or that IL-2 production intra- and extrathymically is controlled via distinct regulatory mechanisms.


Assuntos
Síndromes de Imunodeficiência/imunologia , Interleucina-2/deficiência , Linfócitos T/imunologia , Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Complexo CD3 , Células Cultivadas , Feminino , Humanos , Síndromes de Imunodeficiência/genética , Recém-Nascido , Interleucina-2/biossíntese , Interleucina-2/genética , Ionomicina/farmacologia , Ativação Linfocitária , Masculino , Receptores de Antígenos de Linfócitos T/análise , Linfócitos T/efeitos dos fármacos
5.
Science ; 291(5503): 478-81, 2001 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-11161200

RESUMO

"Limited control" models of reproductive skew in cooperative societies suggest that the frequency of breeding by subordinates is determined by the outcome of power struggles with dominants. In contrast, "optimal skew" models suggest that dominants have full control of subordinate reproduction and allow subordinates to breed only when this serves to retain subordinates' assistance with rearing dominants' own litters. The results of our 7-year field study of cooperative meerkats, Suricata suricatta, support the predictions of limited control models and provide no indication that dominant females grant reproductive concessions to subordinates to retain their assistance with future breeding attempts.


Assuntos
Carnívoros/fisiologia , Comportamento Cooperativo , Dominação-Subordinação , Reprodução , Comportamento Sexual Animal , África Austral , Envelhecimento , Animais , Comportamento Animal , Peso Corporal , Feminino , Masculino , Modelos Biológicos , Chuva , Estações do Ano
7.
Bone Marrow Transplant ; 40(1): 29-35, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17468769

RESUMO

Impaired linear growth has been shown to occur in individuals treated during childhood with single-dose and fractionated total body irradiation (TBI) before stem cell transplantation. Our objective was to describe the final heights attained and patient/treatment factors correlating with final height in a cohort of childhood cancer survivors treated with hyperfractionated TBI (total dose 1375 or 1500 cGy). Thirty individuals (18 men) were included in the study. The mean final height standard deviation score (s.d.s.) was -1.9 +/- 0.2, significantly lower than height s.d.s. at TBI (-0.2 +/- 0.2, P < 0.001). Final height s.d.s. was significantly correlated with age at diagnosis, age at TBI and target height (P = 0.04, P < 0.001, P < 0.001, respectively). Treatment with growth hormone (GH) (n = 7) maintained mean height s.d.s. at -2.0 from the onset of GH therapy until attainment of final height. The mean final sitting height s.d.s. was -2.2 +/- 0.2 (n = 16), significantly shorter than mean final standing height s.d.s. (P < 0.01). In conclusion, treatment with hyperfractionated TBI is associated with a reduction in standing height and an even greater reduction in sitting height. Final height after hyperfractionated TBI was similar to that reported after fractionated TBI.


Assuntos
Estatura , Neoplasias/terapia , Transplante de Células-Tronco , Condicionamento Pré-Transplante , Irradiação Corporal Total , Adulto , Criança , Pré-Escolar , Feminino , Crescimento/efeitos da radiação , Humanos , Lactente , Masculino , Neoplasias/radioterapia , Pais , Seleção de Pacientes , Transplante Autólogo , Transplante Homólogo , Irradiação Corporal Total/métodos
8.
Bone Marrow Transplant ; 40(5): 481-6, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17618322

RESUMO

Daclizumab has been shown to have activity in acute GVHD, but appears to be associated with an increased risk of infection. To investigate further the long-term effects of daclizumab, we performed a retrospective review of 57 patients who underwent an allogeneic hematopoietic stem cell transplant from January 1993 through June 2000 and were treated with daclizumab for steroid-refractory acute GVHD. The median number of daclizumab doses given was 5 (range 1-22). GVHD was assessed at baseline, days 15, 29 and 43. By day 43, 54% patients had an improvement in their overall GVHD score, including 76% patients aged < or =18. Opportunistic infections developed in 95% patients. Forty-three patients (75%) died following treatment with daclizumab. The causes of death included active GVHD and infection (79%), active GVHD (5%), chronic GVHD (2%) and relapse (14%). Patients with grade 3-4 GVHD had a significantly shorter median survival than patients with grade 1-2 GVHD (2.0 vs 5.1 months, P=0.001). Daclizumab has no infusion-related toxicity, is active in steroid-refractory GVHD, especially among pediatric patients, but is associated with significant morbidity and mortality due to infectious complications. Careful patient selection and aggressive prophylaxis against viral and fungal infections are recommended.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Resistência a Medicamentos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Imunoglobulina G/administração & dosagem , Doença Aguda , Adolescente , Adulto , Anticorpos Monoclonais Humanizados , Causas de Morte , Criança , Pré-Escolar , Daclizumabe , Avaliação de Medicamentos , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/induzido quimicamente , Estudos Retrospectivos , Esteroides/farmacologia , Transplante Homólogo
9.
Clin Biomech (Bristol, Avon) ; 49: 78-84, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28892671

RESUMO

BACKGROUND: Biomechanical deviations long (approx. 5years) after anterior cruciate ligament reconstruction have not been quantified in males, despite their distinct risk profile as compared to females. These deviations can indicate altered joint loading during chronic, repetitive motions. METHODS: Cross-sectional study, comparing kinematic and kinetic variables between 15 male anterior cruciate ligament reconstructed patients and 15 healthy controls. During walking and running gait, measurements were taken of impact dynamics, knee and hip sagittal plane angles and moments, and knee varus angles and adduction moments. FINDINGS: Comparing affected limbs to control limbs, significantly lower maximum (P=0.001) and initial (P=0.003) loading rates were found during running, but not in walking. Hip angles were lower for affected limbs of patients compared to the control group (P=0.039) in walking, but not during running. Between-limb comparisons showed important differences in symmetry of the affected patients. Maximum force during running was higher in the unaffected limb (P=0.015), which was linked with a higher loading rate (P=0.008). Knee flexion angle was reduced by 2° on average for the affected limb during running (P=0.010), and both walking and running knee and hip moments showed differences. Knee varus angle showed a 1° difference during walking (P<0.001), but not during running. Knee adduction moment was significantly lower (more valgus) during both walking and running. INTERPRETATION: Male anterior cruciate ligament reconstructed patients demonstrate persistent, clinically important gait asymmetries and differences from healthy controls long after surgery in kinematics, kinetics, and impact biomechanics.


Assuntos
Lesões do Ligamento Cruzado Anterior/fisiopatologia , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Marcha/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos Transversais , Humanos , Traumatismos do Joelho/cirurgia , Articulação do Joelho/fisiologia , Masculino , Inquéritos e Questionários , Caminhada/fisiologia
10.
J Clin Oncol ; 17(1): 197-207, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10458234

RESUMO

PURPOSE: A retrospective analysis of the treatment of childhood acute lymphoblastic leukemia (ALL) in second remission (CR2) was undertaken at our institution to compare the outcome and prognostic factors of patients treated with chemotherapy or allogeneic bone marrow transplantation (BMT). PATIENTS AND METHODS: Seventy-five children who suffered a medullary relapse and achieved a second remission were treated with either an unmodified allogeneic HLA-matched sibling BMT after hyperfractionated total body irradiation (TBI) and cyclophosphamide (n = 38) or chemotherapy according to institutional chemotherapy protocols (n = 37). To avoid the bias of survival from the attainment of second remission in favor of BMT, the final comparative statistical analysis used the landmark approach and comprised 37 and 29 patients from the BMT and chemotherapy groups, respectively RESULTS: The disease-free survival (DFS) rate was 62% and 26% at 5 years, respectively, for the BMT and the chemotherapy groups (P = .03), with relapse rates of 19% and 67%, respectively, for these two groups (P = .01). There was an overall advantage for the BMT therapeutic approach, as compared with chemotherapy, for patients with ALL in CR2 (1) for patients with a WBC count (at diagnosis) of 20 x 10(9)/L or higher (DFS, 40% v 0%) and those with a WBC count of less than 20 x 10(9)/L (DFS, 73% v35%), (2) for patients whose duration of CR1 was less than 24 months (DFS 48% v 9%) and for patients whose duration of CR1 was 24 months or longer (DFS, 81% v 37%) and (3) for patients who were initially treated with intensive regimens incorporating more than five chemotherapy agents (DFS, 57% v 20%) and for patients treated with five agents or fewer (DFS, 72% v 32%). CONCLUSION: In our single-institution series, unmodified HLA-matched allogeneic sibling transplants using hyperfractionated TBI and cyclophosphamide for patients with ALL in CR2 have resulted in superior outcome with a significantly improved probability of DFS and a lower relapse rate, as compared with those for patients treated with chemotherapy, regardless of the duration of first remission, the disease characteristics at diagnosis, or the intensity of prior treatment during first remission.


Assuntos
Antineoplásicos/uso terapêutico , Transplante de Medula Óssea , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Prognóstico , Recidiva , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
11.
J Clin Oncol ; 16(5): 1697-706, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9586881

RESUMO

PURPOSE: To improve response and survival rates in patients with high-risk rhabdomyosarcoma (RMS), extraosseous Ewing's sarcoma, and undifferentiated sarcoma, we used a short course of induction with multi-agent chemotherapy, hyperfractionated radiotherapy, and surgery when possible. Consolidation was with intensive chemotherapy and autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: Twenty-six patients (21 with RMS, three with undifferentiated sarcoma, and two with extraosseous Ewing's sarcoma) were entered onto the protocol between June 1990 and March 1994. Induction consisted of ifosfamide, etoposide, doxorubicin, dactinomycin, cyclophosphomide, and vincristine, and a split course of hyperfractionated radiotherapy. Patients who attained a complete response (CR) or good partial response (GPR) received consolidation with high-dose melphalan and etoposide followed by ABMT. RESULTS: Of 26 previously untreated patients 19 (73%) achieved a CR (n=13) or GPR (n=6) at the completion of induction and underwent ABMT. Two-year overall survival (OS) was 56% (95% confidence interval [CI], 36% to 76%) and progression-free survival (PFS) was 53% for the whole group (95% CI, 33% to 73%). CONCLUSION: Consolidation of response by myeloablative chemotherapy was well tolerated. Split-course hyperfractionated radiotherapy did not increase the rate of local control. The results of this short-course therapy were comparable to previous therapies of 1 to 2 years' duration. Induction and consolidation chemotherapy, as well as radiation dose, could be further intensified, since no death due to toxicity occurred among these patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea , Neoplasias Embrionárias de Células Germinativas/terapia , Rabdomiossarcoma/terapia , Sarcoma de Ewing/terapia , Adolescente , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Masculino , Neoplasias Embrionárias de Células Germinativas/mortalidade , Dosagem Radioterapêutica , Rabdomiossarcoma/mortalidade , Sarcoma de Ewing/mortalidade , Taxa de Sobrevida , Transplante Autólogo
12.
J Clin Oncol ; 20(7): 1918-22, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11919252

RESUMO

PURPOSE: To determine whether cryopreserved solutions of the thrombolytic agent alteplase could be used as a safe, effective, and economically reasonable alternative to urokinase in patients presenting with occluded central venous access devices (CVADs). MATERIALS AND METHODS: Alteplase has been reported as an efficacious alternative to urokinase for treatment of occluded CVADs. However, the practicality of using alteplase as the thrombolytic of choice for this indication remained conjectural. To make this approach economically feasible, alteplase was diluted to 1 mg/mL and 2.5-mL aliquots were stored at -20 degrees C until use. A need to confirm that the cryopreserving and thawing of the reconstituted solution did not compromise the safety and efficacy reported from prior trials was recognized. A quality assessment initiative was undertaken to concurrently monitor the safety and efficacy of this approach. Patients presenting with occluded CVADs received a sufficient volume of the thawed alteplase solution to fill the occluded catheter(s). Data, including efficacy, adverse reactions, dwell time, and catheter type, were collected over a 5-month period. RESULTS: One hundred twenty-one patients accounting for 168 attempted clearances were assessable for safety and efficacy. One hundred thirty-six (81%) of the 168 catheter clearance attempts resulted in successful catheter clearance (95% confidence interval, 74% to 86%). No adverse events were reported. CONCLUSION: Cryopreserved 1-mg/mL aliquots of alteplase are safe and effective in the clearance of occluded CVADs when stored at -20 degrees C for 30 days. The ability to cryopreserve alteplase aliquots makes it an economically reasonable alternative to urokinase in the setting of CVAD occlusion.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Criopreservação/normas , Fibrinolíticos/economia , Fibrinolíticos/uso terapêutico , Ativador de Plasminogênio Tecidual/economia , Ativador de Plasminogênio Tecidual/uso terapêutico , Trombose Venosa/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise Custo-Benefício , Estudos de Viabilidade , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Ativador de Plasminogênio Tecidual/efeitos adversos , Estados Unidos , Trombose Venosa/etiologia
14.
Front Biosci ; 6: G17-22, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11487479

RESUMO

Abnormalities of endocrine function and growth are common following stem cell transplantation in the pediatric/adolescent population. Impaired linear growth and adult short stature are associated with younger age at transplant, use of TBI and prior cranial irradiation, and development of chronic GvHD. Primary hypothyroidism is the most common abnormality of the thyroid and is observed in 10-28% of cases following fractionated TBI. Autoimmune hyperthyroidism has also been described post-stem cell transplant and most often results from adoptive transfer of abnormal clones of T or B cells from donor to recipient. Gonadal dysfunction is extremely prevalent and includes oligo-azoospermia in the majority of males treated with TBI, and primary ovarian failure in most women treated with TBI or Busulfan/Cyclophosphamide. Leydig cell function, however, is retained in most males treated with standard forms of cytoreduction. Many patients demonstrate reduced bone mineral density and are at risk of developing osteoporosis in the future.


Assuntos
Doenças do Sistema Endócrino/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adolescente , Criança , Feminino , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/fisiopatologia , Humanos , Hipotálamo/fisiopatologia , Masculino , Osteoporose/etiologia , Hipófise/fisiopatologia , Reprodução/efeitos dos fármacos , Reprodução/efeitos da radiação , Doenças da Glândula Tireoide/etiologia , Irradiação Corporal Total/efeitos adversos
15.
Transplantation ; 60(9): 957-60, 1995 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7491700

RESUMO

The purpose of this study was to describe the clinical presentation, treatment, and outcome of Mycobacterium haemophilum infection in patients undergoing bone marrow transplantation at a cancer center. Bone marrow transplant recipients with M haemophilum infection were identified upon culture of the organism by implementing the organism's unique requirements for growth. This report of the patients' clinical and immunologic course is based on a retrospective chart review. Two distinctly different presentations of M haemophilum infection were observed. Three patients presented with cutaneous lesions, typical of those seen in previous reports of the infection. Two others developed pulmonary disease only. All patients received directed therapy against M haemophilum, but respiratory failure developed in the patients with pneumonia and they died. The remaining 3 patients survived and are free of infection. These are the only reported cases of M haemophilum infection in bone marrow transplant recipients. Early diagnosis obtained through biopsy and special request for culture conditions conducive to the growth of the organism may decrease morbidity and mortality, particularly in patients with pulmonary disease.


Assuntos
Transplante de Medula Óssea , Infecções por Mycobacterium/fisiopatologia , Mycobacterium haemophilum , Complicações Pós-Operatórias/microbiologia , Adulto , Feminino , Humanos , Masculino , Infecções por Mycobacterium/diagnóstico , Infecções por Mycobacterium/imunologia , Estudos Retrospectivos
16.
Transplantation ; 51(2): 524-31, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1994549

RESUMO

L-leucyl-L-leucine methyl ester (LLME) is a lysosomotropic agent that in microMolar concentrations has been found to be selectively toxic to human and murine precursor and effector cytotoxic cells, irrespective of their surface membrane phenotype. We describe a new method of synthesis of LLME and evaluate the effects of this preparation on human lymphoid and hematopoietic progenitor cells. The new method of synthesis did not change the previously characterized activities of LLME. Consistent with previous observations, NK effectors, LAK precursors and effectors, and allospecific CTL (aCTL) effectors were completely ablated by treatment with 50-250 microM LLME, while the activities of helper T cells and B cells were preserved after treatments of up to 1000 microM LLME. The effects of LLME treatment on human marrow-derived erythroid, myeloid, and monocyte progenitors have not been previously described. We found that the growth of each of these committed precursors was reduced or eliminated following treatment with 100-250 microM LLME. Admixture of LLME-treated marrow with marrow depleted of T cells and other mature cellular elements resulted in increased growth of myeloid and erythroid colonies suggesting that cells that could provide colony-enhancing activities were preserved. In contrast to previous studies in humans, we found a minority of individuals to have aCTL precursors that were partially resistant to LLME. PBL from 10 of 15 individuals tested showed nearly complete ablation of aCTL precursors following treatment with 375 microM LLME. The remaining 5 individuals demonstrated significant aCTL precursor activity after identical treatment. The resistance to LLME was restricted to aCTL precursors, and neither increasing the dose of LLME nor prolonging the time of treatment completely overcame the resistance. The pattern of susceptibility (sensitive versus resistant) was found to be independent of the degree or type of HLA disparity between responder and stimulator. LLME-treated cultures with and without CTL activity contained a predominance of CD4+ T cells. However, in the subjects tested LLME-resistant aCTL was shown to be CD8+. In vitro priming of aCTL precursors from sensitive individuals did not consistently result in the development of resistance to LLME. These data indicate that further studies are needed to evaluate the effects of LLME on human stem cells and to determine the potential role of resistant aCTL precursors in GvHD prior to application of this technique as a form of selective T cell depletion in humans.


Assuntos
Citotoxicidade Imunológica/efeitos dos fármacos , Dipeptídeos/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Formação de Anticorpos/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Dipeptídeos/síntese química , Relação Dose-Resposta a Droga , Hematopoese/efeitos dos fármacos , Humanos , Técnicas In Vitro , Células Matadoras Ativadas por Linfocina/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos T Citotóxicos/efeitos dos fármacos
17.
Transplantation ; 72(12): 1986-90, 2001 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-11773900

RESUMO

BACKGROUND: Chronic lung disease and pulmonary failure are complications that can occur after bone marrow transplantation (BMT) and are associated with severe morbidity and mortality. METHODS: We report on four patients who developed chronic, progressive, and irreversible lung disease 1 to 3 years after allogeneic BMT in childhood. These patients had chronic graft-versus-host disease (n=3) or radiation-related pulmonary fibrosis (n=1). Three patients underwent double lung transplants and one patient underwent a single lung transplant 2 to 14 years after BMT. RESULTS: All four patients tolerated the lung transplantation procedure well and showed significant clinical improvement with normalization of pulmonary function tests by 1 year posttransplant. One patient died from infectious complications 3 years after lung transplantation, and one patient died after chronic rejection of the transplanted lungs 6 years posttransplant. Two patients remain alive without significant respiratory impairment 2 and 7 years after lung transplantation. CONCLUSION: We conclude that lung transplantation offers a viable therapeutic option for patients who develop respiratory failure secondary to BMT.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Pneumopatias/etiologia , Pneumopatias/cirurgia , Transplante de Pulmão , Adolescente , Adulto , Criança , Pré-Escolar , Evolução Fatal , Humanos , Masculino , Transplante Homólogo , Resultado do Tratamento
18.
Hum Immunol ; 25(3): 181-93, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2670851

RESUMO

The circulating lymphoid cells of eight consecutive untreated infants with severe combined immunodeficiency disease (SCID) with B cells were analyzed for surface marker expression and function. The B cells of these children expressed sIg, HLA-DR, CD19 (B4), CD20 (B1), CD21 (B2), Leu-8, and lacked expression of CD10 (CALLA), as do normal peripheral blood B lymphocytes. SCID B cells also expressed antigens that are normally absent or present on only a minor subset of circulating adult B lymphocytes, including CD1c (M241), CD38 (OKT10), CD23 (PL13), with or without concomitant CD5 (Leu-1) expression. The B cells of these children were capable of proliferating in vitro when stimulated with Staphylococcus aureus Cowan I. However, in the presence of pokeweed mitogen, S. aureus Cowan I, and normal T cells, the sIg+ cells of these children produced only IgM. Studies performed on normal B cells obtained from cord blood, young children, and adults reveal that whereas cord blood B cells are predominantly CD1c, CD38, and CD23 positive, B-cell expression of these antigens decreases with age. Cord blood B cells, similar to SCID B cells, produce only IgM when stimulated in vitro with pokeweed mitogen and S. aureus Cowan I. Based on these observations, we hypothesize that SCID B cells represent a population of B cells present during normal B-cell ontogeny which becomes a minor subset when an individual develops full immunologic competence.


Assuntos
Antígenos de Superfície/análise , Linfócitos B/metabolismo , Síndromes de Imunodeficiência/imunologia , Anticorpos Monoclonais , Linhagem Celular Transformada , Separação Celular , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Lactente , Recém-Nascido , Masculino , Monócitos/análise
19.
Hum Immunol ; 26(1): 27-38, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2528525

RESUMO

We have studied the tolerance of engrafted T cells from a severe combined immunodeficiency disease patient sequentially transplanted with T-cell-depleted bone marrow from both HLA haploidentical parents. The T cells from this patient were shown by HLA typing and cytogenetic analysis to be of material origin (donor of the second graft) while HLA typing of peripheral E--populations and of an Epstein-Barr virus-transformed B-cell line established 2 1/2 years after transplantation revealed the presence of host, maternal, and paternal (donor of the first graft) HLA antigens. When tested at 30 and 60 months after the last transplant, engrafted T cells from this patient had only weak mixed lymphocyte culture reactivity to paternal cells which could be inhibited by monoclonal antibodies to HLA-DQ and DR but not by anti-DP. T cells obtained 60 months after transplant were stimulated with paternal cells in both bulk and limiting dilution cultures and failed to generate typical allocytotoxic cells to paternal T- or B-cell targets. Mixed lymphocyte cultures performed at 71 months revealed an increased proliferative response by patient cells to paternal antigens; however, the engrafted T cells remained tolerant to maternal and host antigens. Limiting dilution analysis performed at this time revealed the presence of cytolytic cells directed to paternal antigens. There were no detectable B cells (only identified source of paternal antigen) as measured by immunofluorescent analysis of peripheral blood, nor any evidence of B-cell function as assessed by in vitro assays (proliferation to staphylococcus aureus Cowen strain A and mitogen-stimulated immunoglobulin production) or in vivo production of serum immunoglobulin at 60 and 71 months. The appearance of alloreactivity associated with the loss of B cells in this patient further supports the conclusion that the maintenance of tolerance to major histocompatibility complex disparate cells requires the continued in vivo presence of cells bearing the tolerizing antigens.


Assuntos
Transplante de Medula Óssea , Síndromes de Imunodeficiência/imunologia , Formação de Anticorpos , Linfócitos B/análise , Testes Imunológicos de Citotoxicidade , Feminino , Antígenos HLA/análise , Humanos , Tolerância Imunológica , Síndromes de Imunodeficiência/terapia , Contagem de Leucócitos , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Masculino
20.
Hum Immunol ; 29(1): 42-55, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2211189

RESUMO

Patients who have become split lymphoid chimeras (T cells of donor origin, B cells and monocytes of host origin) following transplantation of HLA-haploidentical marrow for the treatment of severe combined immunodeficiency disease provide a unique model for the study of tolerance. One such patient, UPN 345, was transplanted with maternal marrow and was found to have antidonor proliferative reactivity without detectable donor-directed cytotoxicity when tested at 18, 23, and 66 mos following bone marrow transplantation. In bulk culture, the proliferation to donor cells could be blocked by monoclonal antibodies to HLA-DR and -DQ. Nine clones with antidonor reactivity were established by limiting dilution techniques from a mixed lymphocyte culture between engrafted T cells and irradiated donor E rosette-negative cells. All of the clones were of maternal donor origin, and all were CD3+CD4+CD8-. The clones were tested for proliferative and cytotoxic activity toward donor, host, and paternal B-lymphoblastoid cell lines (B-LCL). Six clones proliferated strongly to maternal B-LCL but not to host B-LCL. Six clones were found to exclusively lyse maternal B-LCL. Four of the clones had both antidonor cytotoxic and antidonor proliferative reactivity. Monoclonal antibody blocking studies were performed on five of the six clones with cytotoxic activity. The antidonor cytotoxicity was not inhibited by monoclonal antibodies to class I determinants; however, three clones were inhibited in the presence of monoclonal antibody to DR, one clone was inhibited by anti-DQ monoclonal antibody, and one clone was inhibited by anti-DP monoclonal antibody. The cytotoxicity of all five clones was inhibited by monoclonal antibody to CD4. These data indicate that antidonor reactivity may also include a cytotoxic component which is not apparent in bulk cultures and which, based on our limiting dilution studies, is probably controlled by regulatory cells. Both the antidonor cytotoxicity and the antidonor proliferation appear to be directed primarily toward donor HLA class II antigens that are not shared with the patient.


Assuntos
Transplante de Medula Óssea/imunologia , Síndromes de Imunodeficiência/imunologia , Linfócitos T/imunologia , Adulto , Anticorpos Monoclonais , Células Clonais , Citotoxicidade Imunológica/imunologia , Feminino , Antígenos HLA-D/imunologia , Reação Hospedeiro-Enxerto/imunologia , Humanos , Tolerância Imunológica/imunologia , Síndromes de Imunodeficiência/terapia , Recém-Nascido , Ativação Linfocitária/imunologia , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA