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BACKGROUND: The introduction of anti-programmed cell death protein 1 (PD-1) immunotherapy has revolutionized the treatment landscape for melanoma, enhancing both response rates and survival outcomes in patients with advanced stages of the disease. Despite these remarkable advances, a noteworthy subset of patients (40%-60%) does not derive advantage from this therapeutic approach. This study aims to identify key predictive factors and create a user-friendly predictive nomogram for stage IV melanoma patients receiving first-line anti-PD-1-based immunotherapy, improving treatment decisions. MATERIALS AND METHODS: In this retrospective study, we included patients with unresectable stage IV melanoma who received first-line treatment with either anti-PD-1 monotherapy or anti-PD-1 plus anti-cytotoxic T-lymphocyte associated protein 4 between 2014 and 2018. We documented clinicopathological features and blood markers upon therapy initiation. By employing the random survival forest model and backward variable selection of the Cox model, we identified variables associated with progression-free survival (PFS) after the first-line anti-PD-1-based treatment. We developed and validated a predictive nomogram for PFS utilizing the identified variables. We assessed calibration and discrimination performance metrics as part of the evaluation process. RESULTS: The study involved 719 patients, divided into a training cohort of 405 (56%) patients and a validation cohort of 314 (44%) patients. We combined findings from the random survival forest and the Cox model to create a nomogram that incorporates the following factors: lactate dehydrogenase (LDH), S100, melanoma subtype, neutrophil-to-lymphocyte ratio (NLR), body mass index, type of immune checkpoint inhibitor, and presence of liver or brain metastasis. The resultant model had a C-index of 0.67 in the training cohort and 0.66 in the validation cohort. Performance remained in different patient subgroups. Calibration analysis revealed a favorable correlation between predicted and actual PFS rates. CONCLUSIONS: We developed and validated a predictive nomogram for long-term PFS in patients with unresectable stage IV melanoma undergoing first-line anti-PD-1-based immunotherapy.
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Imunoterapia , Melanoma , Estadiamento de Neoplasias , Nomogramas , Humanos , Melanoma/tratamento farmacológico , Melanoma/mortalidade , Melanoma/imunologia , Melanoma/patologia , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Imunoterapia/métodos , Idoso , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Adulto , Receptor de Morte Celular Programada 1/antagonistas & inibidoresRESUMO
Quantifying spatial and temporal fluxes of phosphorus (P) within and among agricultural production systems is critical for sustaining agricultural production while minimizing environmental impacts. To better understand P fluxes in agricultural landscapes, P-FLUX, a detailed and harmonized dataset of P inputs, outputs, and budgets, as well as estimated uncertainties for each P flux and budget, was developed. Data were collected from 24 research sites and 61 production systems through the Long-term Agroecosystem Research (LTAR) network and partner organizations spanning 22 U.S. states and 2 Canadian provinces. The objectives of this paper are to (a) present and provide a description of the P-FLUX dataset, (b) provide summary analyses of the agricultural production systems included in the dataset and the variability in P inputs and outputs across systems, and (c) provide details for accessing the dataset, dataset limitations, and an example of future use. P-FLUX includes information on select site characteristics (area, soil series), crop rotation, P inputs (P application rate, source, timing, placement, P in irrigation water, atmospheric deposition), P outputs (crop removal, hydrologic losses), P budgets (agronomic budget, overall budget), uncertainties associated with each flux and budget, and data sources. Phosphorus fluxes and budgets vary across agricultural production systems and are useful resources to improve P use efficiency and develop management strategies to mitigate environmental impacts of agricultural systems. P-FLUX is available for download through the USDA Ag Data Commons (https://doi.org/10.15482/USDA.ADC/1523365).
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Agricultura , Fósforo , Canadá , Fósforo/análise , Solo , Estados Unidos , ÁguaRESUMO
Robust and flexible continuous unit operations that enable the establishment of intensified bioprocesses is one of the most relevant trends in manufacturing of biopharmaceuticals, including virus-based products. Sulfated cellulose membrane adsorbers (SCMA) are one of the most promising matrices for chromatographic purification of virus particles, like influenza viruses. Here, a three 'column' periodical counter current set-up was used to continuously purify influenza A/PR/8/34 virus particles using SCMA in bind-elute mode. It was possible to recover 67.4% of the HA-activity and to remove 67.4% and 99.8% of the total protein and DNA, respectively. The performance of the continuous process operated over a total of 10 loops, was slightly inferior to was obtained in a comparable batch process. Nevertheless, it was possible to increase the effective usage of binding capacity to 80%, resulting on a productivity of 22.8 kHAU mlmemb-1 min-1. As a proof-of-principle, SCMA were successfully used as matrix for purification of cell-derived influenza virus particles, in continuous mode.
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Vírus da Influenza A , Orthomyxoviridae , Celulose , Cromatografia de Afinidade , MembranasRESUMO
The development of biotechnology-based active pharmaceutical ingredients, such as GLP-1 analogs, brought changes in type 2 diabetes treatment options. For better therapeutic efficiency, these active pharmaceutical ingredients require appropriate administration, without the development of adverse effects or toxicity. Therefore, it is required to develop several quantification methods for GLP-1 analogs products, in order to achieve the therapeutic goals, among which ELISA and HPLC arise. These methods are developed, optimized and validated in order to determine GLP-1 analogs, not only in final formulation of the active pharmaceutical ingredient, but also during preclinical and clinical trials assessment. This review highlights the role of ELISA and HPLC methods that have been used during the assessment for GLP-1 analogs, especially for exenatide.
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This report is on two novel patients with RFT1-CDG. Their phenotype is characterized by mild psychomotor disability, behavioral problems, ataxia, and mild dysmorphism. Neither of them shows signs of epilepsy, which was observed in all RFT1-CDG patients reported to date (n = 14). Also, deafness, which is often associated with this condition, was not observed in our patients. Molecular analysis of RFT1 showed biallelic missense variants including three novel ones: c.827G > A (p.G276D), c.73C > T (p.R25W), and c.208T > C (p.C70R).
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BACKGROUND: Vaccines based on virus-like particles (VLPs) are an alternative to inactivated viral vaccines that combine good safety profiles with strong immunogenicity. In order to be economically competitive, efficient manufacturing is required, in particular downstream processing, which often accounts for major production costs. This study describes the optimization and establishment of a chromatography capturing technique using sulfated cellulose membrane adsorbers (SCMA) for purification of influenza VLPs. RESULTS: Using a design of experiments approach, the critical factors for SCMA performance were described and optimized. For optimal conditions (membrane ligand density: 15.4 µmol cm-2, salt concentration of the loading buffer: 24 mmol L-1 NaCl, and elution buffer: 920 mmol L-1 NaCl, as well as the corresponding flow rates: 0.24 and 1.4 mL min-1), a yield of 80% in the product fraction was obtained. No loss of VLPs was detected in the flowthrough fraction. Removal of total protein and DNA impurities were higher than 89% and 80%, respectively. CONCLUSION: Use of SCMA represents a significant improvement compared with conventional ion exchanger membrane adsorbers. As the method proposed is easily scalable and reduces the number of steps required compared with conventional purification methods, SCMA could qualify as a generic platform for purification of VLP-based influenza vaccines. © 2017 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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In the last decades, nine inherited errors of the distal part of cholesterol biosynthesis have been recognized. Affected patients present complex malformation syndromes involving different organs and systems with variable degrees of severity. We report on the phenotype evolution of three patients with enzymatic defects at three distinct steps of such pathway: Smith-Lemli-Opitz syndrome, X-linked dominant chondrodysplasia punctata type 2 and congenital hemidysplasia with ichthyosiform erythroderma and limb defects syndrome. The patients' natural history, from childhood to adulthood, is thoroughly described in order to contribute for a better knowledge of these diseases. Our ultimate goals are to contribute for a better characterization of the long-term course of these metabolic disorders and for the recognition of such diseases in older patients.
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Anormalidades Múltiplas/fisiopatologia , Condrodisplasia Punctata/fisiopatologia , Doenças Genéticas Ligadas ao Cromossomo X/fisiopatologia , Eritrodermia Ictiosiforme Congênita/fisiopatologia , Deformidades Congênitas dos Membros/fisiopatologia , Fenótipo , Síndrome de Smith-Lemli-Opitz/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Colesterol/biossíntese , Progressão da Doença , Feminino , Humanos , Recém-Nascido , MasculinoRESUMO
Cystinuria is a rare autosomal inherited disorder characterized by impaired transport of cystine and dibasic aminoacids in the proximal renal tubule. Classically, cystinuria is classified as type I (silent heterozygotes) and non-type I (heterozygotes with urinary hyperexcretion of cystine). Molecularly, cystinuria is classified as type A (mutations on SLC3A1 gene) and type B (mutations on SLC7A9 gene). The goal of this study is to provide a comprehensive clinical, biochemical and molecular characterization of a cohort of 12 Portuguese patients affected with cystinuria in order to provide insight into genotype-phenotype correlations. We describe seven type I and five non-type I patients. Regarding the molecular classification, seven patients were type A and five were type B. In SLC3A1 gene, two large genomic rearrangements and 13 sequence variants, including four new variants c.611-2A>C; c.1136+44G>A; c.1597T (p.Y533N); c.*70A>G, were found. One large genomic rearrangement was found in SLC7A9 gene as well as 24 sequence variants including 3 novel variants: c.216C>T (p.C72C), c.1119G>A (p.S373S) and c.*82C>T. In our cohort the most frequent pathogenic mutations were: large rearrangements (33.3% of mutant alleles) and a missense mutation c.1400T>C (p.M467T) (11.1%). This report expands the spectrum of SLC3A1 and SLC7A9 mutations and provides guidance in the clinical implementation of molecular assays in routine genetic counseling of Portuguese patients affected with cystinuria.
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Aminoácidos/urina , Cistinúria/genética , Variação Estrutural do Genoma , Adolescente , Alelos , Sistemas de Transporte de Aminoácidos Básicos/genética , Sistemas de Transporte de Aminoácidos Neutros/genética , Criança , Pré-Escolar , Estudos de Coortes , Biologia Computacional , Cistina/metabolismo , Cistinúria/diagnóstico , Cistinúria/epidemiologia , Cistinúria/metabolismo , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Testes Genéticos , Genoma Humano , Genótipo , Humanos , Lactente , Masculino , Mutação de Sentido Incorreto , Portugal/epidemiologia , PrevalênciaRESUMO
Obstructive sleep apnoea (OSA) seems to worsen metabolism. This effect has not been evaluated in morbid obesity (MO). We hypothesised that the metabolic profile is more impaired in MO patients with OSA than in those without, and investigated whether any specific metabolic dysfunction is related to OSA in MO. A prospective multicentre cross-sectional study was conducted in consecutive subjects before bariatric surgery. OSA was defined as apnoea/hypopnoea index (AHI) ≥15 by overnight polysomnography. Anthropometrical, blood pressure (BP) and fasting blood measurements were obtained the morning after. Metabolic syndrome (MetS) was defined according to National Cholesterol Education Program Adult Treatment Panel III modified criteria. 159 patients were studied: 72% were female and 72% had OSA. MetS prevalence was 70% in OSA versus 36% in non-OSA (p<0.001). As AHI severity increased, metabolic parameters progressively worsened, even in those without type 2 diabetes (DM2). AHI was independently associated with systolic and diastolic BP, triglycerides and the percentage of glycosylated haemoglobin (HbA1c) in the total sample, and with systolic BP, high-density lipoprotein cholesterol and HbA1c in those samples without DM2. OSA increased the adjusted odds ratio of having MetS by 2.8 (95% CI 1.3-6.2; p=0.009). In MO, OSA is associated with major metabolic impairment caused by higher BP and poorer lipid and glucose control, independent of central obesity or DM2.
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Síndrome Metabólica/complicações , Obesidade Mórbida/complicações , Apneia Obstrutiva do Sono/complicações , Adolescente , Adulto , Glicemia/análise , Pressão Sanguínea , Diabetes Mellitus Tipo 2/complicações , Feminino , Hemoglobinas Glicadas/análise , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/metabolismo , Oxigênio/sangue , Polissonografia , Apneia Obstrutiva do Sono/fisiopatologia , Adulto JovemRESUMO
STUDY OBJECTIVES: The process of intermittent hypoxia-reoxygenation produces airway inflammation and endothelial dysfunction that favors the development of cardiovascular disorders in obstructive sleep apnea syndrome (OSAS). Nitric oxide (NO) is an important mediator in airway inflammation and the regulation of endothelium-dependent vasodilation. DESIGN: This study compared airway NO (FE(NO)) and alveolar NO (CA(NO)) measurements in exhaled breath in 30 OSAS patients to those of 30 healthy (non-OSAS) individuals and determined the relationship between NO levels and OSAS severity. Additionally, NO measurements were analyzed after 3 months of CPAP treatment. MEASUREMENTS AND RESULTS: The mean (±SD) FE(NO) level in the OSAS group (27.2 ± 18 ppb) was higher than in the healthy non-OSAS group (p = 0.006). The mean CA(NO) level was 1.65 ± 0.90 ppb, lower than in the non-OSAS group (p = 0.001). A significant correlation was found between FE(NO) and CA(NO) levels and the apnea-hypopnea index (AHI) in the OSAS group (r = 0.8, p < 0.05; r = -0.9, p = 0.01, respectively). FE(NO) levels decreased and CA(NO) levels increased significantly after CPAP treatment. CONCLUSIONS: Severe OSAS patients have higher FE(NO) and lower CA(NO) levels and these are restored to normal after CPAP treatment, reflecting the correction of local upper airway inflammation and endothelial dysfunction present in OSAS patients. Exhaled breath techniques can be useful to identify airway inflammation and endothelial dysfunction in severe OSAS patients.
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Hipóxia/metabolismo , Óxido Nítrico/metabolismo , Alvéolos Pulmonares/metabolismo , Apneia Obstrutiva do Sono/metabolismo , Doenças Cardiovasculares/prevenção & controle , Pressão Positiva Contínua nas Vias Aéreas , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hipóxia/fisiopatologia , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapiaRESUMO
SLC26A2-related dysplasias encompass a spectrum of diseases: from lethal achondrogenesis type 1B (ACG1B; MIM #600972) and atelosteogenesis type 2 (AO2; MIM #256050) to classical diastrophic dysplasia (cDTD; MIM #222600) and recessive multiple epiphyseal dysplasia (rMED; MIM #226900). This study aimed at characterizing clinically, radiologically and molecularly 14 patients affected by non-lethal SLC26A2-related dysplasias and at evaluating genotype-phenotype correlation. Phenotypically, eight patients were classified as cDTD, four patients as rMED and two patients had an intermediate phenotype (mild DTD - mDTD, previously 'DTD variant'). The Arg279Trp mutation was present in all patients, either in homozygosity (resulting in rMED) or in compound heterozygosity with the known severe alleles Arg178Ter or Asn425Asp (resulting in DTD) or with the mutation c.727-1G>C (causing mDTD). The 'Finnish mutation', c.-26+2T>C, and the p.Cys653Ser, both frequent mutations in non-Portuguese populations, were not identified in any of the patients of our cohort and are probably very rare in the Portuguese population. A targeted mutation analysis for p.Arg279Trp and p.Arg178Ter in the Portuguese population allows the identification of approximately 90% of the pathogenic alleles.
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Proteínas de Transporte de Ânions/genética , Nanismo/genética , Estudos de Associação Genética , Adolescente , Adulto , Alelos , Estatura , Criança , Pré-Escolar , Estudos de Coortes , Nanismo/diagnóstico , Nanismo/diagnóstico por imagem , Nanismo/epidemiologia , Feminino , Testes Genéticos , Genótipo , Humanos , Masculino , Mutação , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/genética , Fenótipo , Portugal/epidemiologia , Radiografia , Transportadores de Sulfato , População Branca/genética , Adulto JovemAssuntos
Analgesia Epidural/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Ticlopidina/análogos & derivados , Procedimentos Cirúrgicos Vasculares , Clopidogrel , Hematoma Epidural Espinal/induzido quimicamente , Humanos , Complicações Pós-Operatórias/induzido quimicamente , Guias de Prática Clínica como Assunto , Ticlopidina/efeitos adversosRESUMO
Taurine plays a role in neuronal development. In this study, we examined whether postnatal taurine administration influences the long-term consequences induced by mild neonatal stressors (10 min maternal deprivation plus sham injection, applied daily to neonatal mice up to 21 days). At 30 days of age stressed mice showed higher pain threshold both in the tail-flick--which measures mostly the spinal mechanisms of pain--and in the hot-plate test--which reflects mainly the supraspinal mechanisms of pain. The latter effect was prevented completely by neonatal taurine administration, while the tail-flick test was not affected, thus suggesting that spinal pain is not sensitive to taurine treatment. At 140 days of age, mice which were stressed during the neonatal period showed consistent decrease in immobility time in forced swimming test, and taurine did not influence this parameter. At the same age, the fear/anxiety axis, measured with elevated plus maze test, did not show any consistent changes. Electrophysiological experiments in brain slices obtained from adult mice showed that input-output curves in hippocampal CA1 were increased by taurine administration in lactation. Hence, neonatal administration of taurine might permanently modify the functioning of hippocampus, a brain area which is known to be crucial for learning and memory.
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Hipocampo/efeitos dos fármacos , Lactação/efeitos dos fármacos , Estresse Psicológico/fisiopatologia , Taurina/administração & dosagem , Análise de Variância , Animais , Animais Recém-Nascidos , Constituição Corporal , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta à Radiação , Estimulação Elétrica , Feminino , Hipocampo/citologia , Técnicas In Vitro , Potenciação de Longa Duração , Masculino , Privação Materna , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Medição da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , GravidezRESUMO
Aerial parts of Centaurea tweediei from Argentina afforded as the main constituent the sesquiterpene lactone onopordopicrin and minor amounts of a new heliangolide, a new guaianolide, a new eudesmanolide, a new eudesmane acid and the lignans arctigenin and matairesinol.
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Inherited limb malformations provide a valuable resource for the identification of genes involved in limb development. Brachydactyly type B (BDB), an autosomal dominant disorder, is the most severe of the brachydactylies and characterized by terminal deficiency of the fingers and toes. In the typical form of BDB, the thumbs and big toes are spared, sometimes with broadening or partial duplication. The BDB1 locus was previously mapped to chromosome 9q22 within an interval of 7.5 cM (refs 9,10). Here we describe mutations in ROR2, which encodes the orphan receptor tyrosine kinase ROR2 (ref. 11), in three unrelated families with BDB1. We identified distinct heterozygous mutations (2 nonsense, 1 frameshift) within a 7-amino-acid segment of the 943-amino-acid protein, all of which predict truncation of the intracellular portion of the protein immediately after the tyrosine kinase domain. The localized nature of these mutations suggests that they confer a specific gain of function. We obtained further evidence for this by demonstrating that two patients heterozygous for 9q22 deletions including ROR2 do not exhibit BDB. Expression of the mouse mouse orthologue, Ror2, early in limb development indicates that BDB arises as a primary defect of skeletal patterning.
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Dedos/anormalidades , Genes Dominantes , Receptores Proteína Tirosina Quinases/genética , Receptores de Superfície Celular/genética , Sequência de Aminoácidos , Animais , Cromossomos Humanos Par 9/genética , Feminino , Dedos/embriologia , Mutação da Fase de Leitura , Heterozigoto , Humanos , Masculino , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Linhagem , Fenótipo , Receptores Proteína Tirosina Quinases/deficiência , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase , Receptores de Superfície Celular/deficiência , Deleção de SequênciaRESUMO
The major elements of bone pathology in Gaucher disease are a failure of osteoclast and osteoblast function, resulting in osteopenia and also osteonecrosis. T lymphocytes have recently been found to be involved in the regulation of osteoblast/osteoclast activity in vitro. In the present report the peripheral blood T major lymphocyte subsets were investigated in a group of genotyped type 1 Gaucher disease patients. A total of 31 patients were studied: 21 non-splenectomized (5 N370S homozygotes) and 10 splenectomized (of whom 1 was a N370S homozygote). The results show that non-splenectomized patients present a decrease in absolute numbers of peripheral blood T lymphocytes, specially the CD4+ T subset. However, when patients were analyzed with respect to the presence of bone disease, the number of CD8+ T lymphocytes was found to be statistically significantly lower in patients presenting bone involvement. Furthermore, lower numbers of CD8+ T lymphocytes were significantly correlated with higher levels of plasma tartrate resistant acid phosphatase (TRAP) activity, a putative marker of osteoclast cell activity. These in vivo findings are in agreement with the results reached in vitro by others. They provide an additional marker of disease severity in Gaucher disease. In the group of genotyped Gaucher disease patients, the majority of the N370S homozygous patients presented a clinically milder phenotype, including the absence of bone involvement, confirming earlier reports predicting that a number of these patients may remain undiagnosed. Collectively the homozygosity for the N370S mutation and normal T cell numbers may provide additional markers for the clinical heterogeneity of Gaucher disease.
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Doenças Ósseas/sangue , Doença de Gaucher/sangue , Linfócitos T/citologia , Fosfatase Ácida/sangue , Fosfatase Ácida/efeitos dos fármacos , Adolescente , Adulto , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Criança , Feminino , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Genótipo , Glucosilceramidase/uso terapêutico , Humanos , Isoenzimas/sangue , Isoenzimas/efeitos dos fármacos , Contagem de Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Esplenectomia , Fosfatase Ácida Resistente a TartaratoRESUMO
During certain medical procedures, it is important to continuously measure the respiratory flow of a patient, as lack of proper ventilation can cause brain damage and ultimately death. The monitoring of the ventilatory condition of a patient is usually performed with the aid of flowmeters. However, water and other secretions present in the expired air can build up and ultimately block a traditional, restriction-based flowmeter; by using an orifice plate flowmeter, such blockages are minimized. This paper describes the design of an orifice plate flowmetering system including, especially, a description of the numerical and computational techniques adopted in order to simulate human respiratory and sinusoidal air flow across various possible designs for the orifice plate flowmeter device. Parallel computation and multigrid techniques were employed in order to reduce execution time. The simulated orifice plate was later built and tested under unsteady sinusoidal flows. Experimental tests show reasonable agreement with the numerical simulation, thereby reinforcing the general hypothesis that computational exploration of the design space is sufficiently accurate to allow designers of such systems to use this in preference to the more traditional, mechanical prototyping techniques.
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Testes de Função Respiratória/instrumentação , Reologia/instrumentação , Engenharia Biomédica/instrumentação , Desenho de Equipamento , Estudos de Avaliação como Assunto , Humanos , Modelos Biológicos , Monitorização Fisiológica/instrumentação , Mecânica Respiratória/fisiologiaRESUMO
Dendritic cells (DCs) are the most powerful professional antigen-presenting cells (APC), specializing in capturing antigens and stimulating T-cell-dependent immunity. In this study we report the generation and characterization of functional DCs derived from both steady-state bone marrow (BM) and circulating haemopoietic CD34+ cells from 14 individuals undergoing granulocyte colony-stimulating factor (G-CSF) treatment for peripheral blood stem cells (PBSC) mobilization and transplantation. Clonogenic assays in methylcellulose showed an increased frequency and proliferation of colony-forming unit-dendritic cells (CFU-DC) in circulating CD34+ cells, compared to that of BM CD34+ precursors in response to GM-CSF and TNF-alpha with or without SCF and FLT-3L. Moreover, peripheral blood (PB) CD34+ cells generated a significantly higher number of fully functional DCs, as determined by conventional mixed lymphocyte reactions (MLR), than their BM counterparts upon different culture conditions. DCs derived from mobilized stem cells were also capable of processing and presenting soluble antigens to autologous T cells for both primary and secondary immune response. Replacement of the early-acting growth factors SCF and FLT-3L with IL-4 at day 7 of culture of PB CD34+ cells enhanced both the percentage of total CD1a+ cells and CD1a+ CD14- cells and the yield of DCs after 14 d of incubation. In addition, the alloreactivity of IL-4-stimulated DCs was significantly higher than those generated in the absence of IL-4. Furthermore, autologous serum collected during G-CSF treatment was more efficient than fetal calf serum (FCS) or two different serum-free media for large-scale production of DCs. Thus, our comparative studies indicate that G-CSF mobilizes CD34+ DC precursors into PB and circulating CD34+ cells represent the optimal source for the massive generation of DCs. The sequential use of early-acting and intermediatelate-acting colony-stimulating factors (CSFs) as well as the use of autologous serum greatly enhanced the growth of DCs. These data may provide new insights for manipulating immunocompetent cells for cancer therapy.
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Antígenos CD34/metabolismo , Células da Medula Óssea/citologia , Adjuvantes Imunológicos/uso terapêutico , Diferenciação Celular , Divisão Celular , Células Cultivadas , Células Dendríticas , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Humanos , Interleucina-4/farmacologia , Lenograstim , Proteínas de Membrana/farmacologia , Proteínas Recombinantes/uso terapêutico , Fator de Células-Tronco/farmacologia , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
In this study, the hypothesis that a subset of granulocyte colony-stimulating factor (G-CSF)-mobilized CD34+ blood cells may actively induce an allogeneic T cell response in vitro was tested. Circulating CD34+ cells were purified to > or =98% by high gradient magnetic separation and then analyzed for the coexpression of HLA-DR, the common beta-chain of the leukointegrin family CD18 and costimulatory molecules CD80 (B7-1) and CD86 (B7-2). These antigens were expressed on average on: 94.9 +/- 2.5%, 64.4 +/- 15.4%, 0% and 1.9 +/- 1.2% CD34+ blood cells, respectively. Irradiated CD34+ cells induced a high proliferative response of allogeneic, but not autologous, purified CD4+ and CD8+ T cells in primary mixed leukocyte culture (MLC). An average three-fold lower CD4+ and CD8+ T cell response was induced by mononuclear cells from G-CSF-treated donors. A lower frequency of allostimulating cells among mononuclear cells rather than among CD34+ cells in the apheresis was documented by limiting dilution assay (LDA). As previously observed with marrow, sorted CD34+/CD18+ cells induced the proliferation of allogeneic T cells in MLC, while CD34+/CD18- cells, which were >94% HLA-DR+ and contained both committed (CFU-C) and early (LTC-IC) hematopoietic progenitors, stimulated allogeneic T cells poorly. Three-color staining cytofluorimetry indicated that expression of CD80 and CD86 were upregulated in 6.9 +/- 4.9 and 10.7 +/- 2.6% CD34+ blood cells respectively, after 24-30 h of culture with autologous or allogeneic mononuclear cells, or with CD4+, or CD8+ T cells, but not with medium alone. Moreover, the upregulation of CD86 was observed on CD34+/CD18+ rather than on CD34+/CD18- cells after 30 h in MLC. Blocking experiments demonstrated that preincubation of stimulator and responder cells with anti-CD80 plus anti-CD86 monoclonal antibodies induced a 84 +/- 8% inhibition of CD34+ cell allostimulating activity after 6 days in primary MLC. These results suggest that G-CSF-mobilized CD34+ hematopoietic progenitors with alloantigen presenting function express CD18 and may upregulate CD80 and CD86 upon interaction with T cells. Since activation of B7 costimulatory molecules represents an active costimulatory pathway on G-CSF-mobilized CD34+ cells, the blockade of these molecules or, alternatively, the use of selected non-immunogenic CD34+/CD18- blood stem cells may represent a new strategy for reducing graft rejection and overcoming HLA barriers in allogeneic stem cell transplantation.