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1.
Alcohol ; 49(7): 647-56, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26493109

RESUMO

The potential of micronutrients to ameliorate the impact of prenatal alcohol exposure (PAE) was explored in a clinical trial conducted in Ukraine. Cardiac orienting responses (ORs) during a habituation/dishabituation learning paradigm were obtained from 6 to 12 month-olds to assess neurophysiological encoding and memory. Women who differed in prenatal alcohol use were recruited during pregnancy and assigned to a group (No study-provided supplements, multivitamin/mineral supplement, or multivitamin/mineral supplement plus choline supplement). Heart rate was collected for 30 s prior to stimulus onset and 12 s post-stimulus onset. Difference values (∆HR) for the first 3 trials of each condition were aggregated for analysis. Gestational blood samples were collected to assess maternal nutritional status and changes as a function of the intervention. Choline supplementation resulted in a greater ∆HR on the visual habituation trials for all infants and for the infants with no PAE on the dishabituation trials. The latency of the response was reduced in both conditions for all infants whose mothers received choline supplementation. Change in gestational choline level was positively related to ∆HR during habituation trials and levels of one choline metabolite, dimethylglycine (DMG), predicted ∆HR during habituation trials and latency of responses. A trend was found between DMG and ∆HR on the dishabituation trials and latency of the response. Supplementation did not affect ORs to auditory stimuli. Choline supplementation when administered together with routinely recommended multivitamin/mineral prenatal supplements during pregnancy may provide a beneficial impact to basic learning mechanisms involved in encoding and memory of environmental events in alcohol-exposed pregnancies as well as non- or low alcohol-exposed pregnancies. Changes in maternal nutrient status suggested that one mechanism by which choline supplementation may positively impact brain development is through prevention of fetal alcohol-related depletion of DMG, a metabolic nutrient that can protect against overproduction of glycine, during critical periods of neurogenesis.


Assuntos
Depressores do Sistema Nervoso Central/efeitos adversos , Suplementos Nutricionais , Etanol/efeitos adversos , Transtornos do Espectro Alcoólico Fetal/prevenção & controle , Processos Mentais/efeitos dos fármacos , Micronutrientes , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal/psicologia , Adulto , Colina/administração & dosagem , Colina/uso terapêutico , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Aprendizagem/efeitos dos fármacos , Testes Neuropsicológicos , Gravidez , Sarcosina/análogos & derivados , Sarcosina/metabolismo , Fatores Socioeconômicos , Ucrânia
2.
J Dairy Sci ; 98(1): 68-77, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25465631

RESUMO

Lactococcus lactis strains depend on a proteolytic system for growth in milk to release essential AA from casein. The cleavage specificities of the cell envelope proteinase (CEP) can vary between strains and environments and whether the enzyme is released or bound to the cell wall. Thirty-eight Lc. lactis strains were grouped according to their CEP AA sequences and according to identified peptides after hydrolysis of milk. Finally, AA positions in the substrate binding region were suggested by the use of a new CEP template based on Streptococcus C5a CEP. Aligning the CEP AA sequences of 38 strains of Lc. lactis showed that 21 strains, which were previously classified as group d, could be subdivided into 3 groups. Independently, similar subgroupings were found based on comparison of the Lc. lactis CEP AA sequences and based on normalized quantity of identified peptides released from αS1-casein and ß-casein. A model structure of Lc. lactis CEP based on the crystal structure of Streptococcus C5a CEP was used to investigate the AA positions in the substrate-binding region. New AA positions were suggested, which could be relevant for the cleavage specificity of CEP; however, these could only explain 2 out of 3 found subgroups. The third subgroup could be explained by 1 to 5 AA positions located opposite the substrate binding region.


Assuntos
Lactococcus lactis/enzimologia , Leite/metabolismo , Serina Endopeptidases/classificação , Serina Endopeptidases/genética , Adesinas Bacterianas , Sequência de Aminoácidos , Animais , Sequência de Bases , Caseínas/metabolismo , Membrana Celular/enzimologia , Parede Celular/enzimologia , Simulação por Computador , Endopeptidases , Hidrólise , Leite/química , Modelos Moleculares , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Serina Endopeptidases/química , Streptococcus/enzimologia
3.
Bone Marrow Transplant ; 48(6): 865-71, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23222378

RESUMO

Patient/caregiver out-of pocket costs associated with hematopoietic cell transplantation (HCT) are not well known. We conducted a pilot study to evaluate patient/caregiver out-of-pocket costs in the first 3 months after allogeneic HCT. Thirty patients were enrolled at three sites. Before HCT, participants completed a baseline survey regarding household income and insurance coverage. Subsequently, they maintained a paper-based diary to track daily out-of-pocket expenses for the first 3 months after HCT. Telephone interviews were conducted to follow-up on the missing/incomplete diaries and on study completion. Twenty-five patients/caregivers completed the baseline survey. Among these, the median pre-tax household income was $66 500 (range, $30-$375 000) and 48% had to temporarily relocate close to the transplant center. Insurance coverage was managed care plan (56%), Medicaid (20%), Medicare (17%) and other (8%). Twenty-two patients/caregivers completed 4 diaries; the median out-of-pocket expenses were $2440 (range, $199-$13 769). Patients/caregivers who required temporary lodging had higher out-of-pocket expenses compared with those who did not (median, $5247 vs $716). Patients/caregivers can incur substantial out-of-pocket costs over the first 3 months, especially if they need to temporarily relocate close to the transplant center. Our study lays the foundation for future research on the early and long-term financial impact of allogeneic HCT on patients/caregivers.


Assuntos
Cuidadores/economia , Transplante de Células-Tronco Hematopoéticas/economia , Seguro Saúde/economia , Adulto , Idoso , Aloenxertos , Custos e Análise de Custo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
4.
Artigo em Inglês | MEDLINE | ID: mdl-18036802

RESUMO

We measured 16 nonesterified oxygenated fatty acid derivatives (oxylipids) in plasmas from seven human subjects. Two arterial samples from each subject were analyzed, drawn approximately 2h apart. We observed a marked increase in levels of most oxylipids in the second sample, as high as 470-fold. Between the first and second samples, subjects received approximately 800-1000 IU of heparin to prevent clotting in intravascular catheters. We postulate that heparin activated lipoprotein lipases, which, in turn, released oxylipids from triglycerides and phospholipids in plasma lipoproteins. Some of that lipolysis may have occurred during sample storage. Measurements of nonesterified lipids in human plasma may be distorted if heparin is administered to subjects before blood is drawn and if lipase inhibitors are omitted from stored samples.


Assuntos
Ácidos Graxos Insaturados/sangue , Heparina/administração & dosagem , Lipoproteínas/sangue , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Cromatografia Líquida , Ácidos Graxos Insaturados/química , Feminino , Heparina/efeitos adversos , Humanos , Infusões Intravenosas , Lipoproteínas/química , Espectrometria de Massas , Obesidade/sangue , Oxirredução/efeitos dos fármacos
5.
Ultrastruct Pathol ; 24(3): 175-82, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10914429

RESUMO

A high-affinity receptor for urokinase-type plasminogen activator (uPAR) has been identified on the plasma membrane of a number of different cell types, and has been shown to be important for plasminogen activation, cell adhesion, and possibly signal transduction. uPAR and uPA cosediment with secretory vesicles and specific granules by subcellular fractionation and translocate to the plasma membrane upon activation of neutrophils. Here the subcellular distribution of uPAR and uPA is studied by electron microscopy of neutrophils using immunogold double labeling for uPAR and uPA and a set of markers for well-defined subtypes of granules: matrix metalloproteinase type-9 (MMP-9) for gelatinase granules, lactoferrin (LF) for specific granules, and myeloperoxidase (MPO) and neutrophil elastase (NE) for primary granules. With this technique uPAR colocalizes with uPA in 71% of labeled granules. In granules containing uPAR the degree of coexpression with MMP-9, MPO and NE was 19, 66, and 74%, respectively. In granules labeled for uPA the corresponding overlap with MMP-9, MPO and NE was 24, 64, and 51%, respectively. Low levels of co-localization were found for uPAR and LF (7%) and for uPA and lactoferrin (5%). The results indicate that uPAR and uPA are present in gelatinase granules and primary granules, but rarely in specific granules. The demonstration of uPAR and uPA in primary granules is of particular interest, and may indicate that uPAR and uPA participate in the activation of latent hepatocyte growth factor of neutrophils.


Assuntos
Precursores Enzimáticos/metabolismo , Neutrófilos/enzimologia , Ativadores de Plasminogênio/metabolismo , Receptores de Superfície Celular/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Biomarcadores/análise , Grânulos Citoplasmáticos/metabolismo , Grânulos Citoplasmáticos/ultraestrutura , Humanos , Microscopia Imunoeletrônica , Neutrófilos/ultraestrutura , Receptores de Ativador de Plasminogênio Tipo Uroquinase
6.
Br J Haematol ; 95(1): 45-51, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8857937

RESUMO

Migration of neutrophils in patients with paroxysmal nocturnal haemoglobinuria (PNH) was studied using two different complement-free in vitro model systems, subagarose and transendothelial migration. In the subagarose migration assay the mean migration distance of PNH neutrophils was slightly, but significantly, reduced to 1236 microns (range 753-1586, n = 6) compared to a normal mean of 1476 microns (range 1076-1768, n = 6, P = 0.016). By immunocytochemical staining for the urokinase type plasminogen activator receptor (uPAR) which is a glycosyl-phosphatidyl-inositol (GPI) anchored protein expressed by normal, but not by PNH-affected, neutrophils, it was shown that the uPAR-positive subpopulation of normal neutrophils predominated among the faster migrating cells (60-80% normal cells at the front of migration) while uPAR-negative (i.e. PNH-affected neutrophils) were more numerous close to the application well (5-30% normal cells). When migration of neutrophils was tested across a monolayer of human umbilical vein endothelial cells (HUVEC) cultured on polycarbonate filters, there was a 3-4-fold impairment of the migration of the PNH-affected neutrophils both in the absence of stimulation and after stimulation with fMLP (P < 0.001 in both cases). After IL-1 stimulation of the endothelium the impairment was even more pronounced (8-fold difference, P < 0.001). When the endothelial cells were grown on collagen-coated filters the impairment of the migration of PNH neutrophils was less pronounced, but still significant after stimulation with fMLP and IL-1 (2-fold, P < 0.05 in both cases). These results demonstrate that there is a complement-independent impairment of migration of neutrophils from patients with PNH which may be related to their failure to express GPI-linked proteins involved in cell migration and/or adhesion such as the uPA receptor and the CD66b antigen.


Assuntos
Movimento Celular/fisiologia , Hemoglobinúria Paroxística/patologia , Neutrófilos/fisiologia , Movimento Celular/efeitos dos fármacos , Humanos , Imuno-Histoquímica , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Ativadores de Plasminogênio/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase
7.
Am J Clin Pathol ; 102(6): 835-41, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7801901

RESUMO

Expression of the receptor for the urokinase type plasminogen activator (uPAR) has been studied by flow cytometry and immunohistology in normal blood and bone marrow cells, in vitro activated lymphoid cells, and tissue samples from reactive lymph nodes (n = 6), thymus (n = 2) and malignant lymphomas (n = 82), or leukemias (n = 32). HL-60 myeloid precursor cells and CD34-positive normal stem cells also were analyzed. In the normal cells, staining was confined to monocytes, macrophages, neutrophils, and myeloid precursors. No labelling was seen of normal or activated lymphoid cells. Purified CD34-positive hematopoietic progenitors were uPAR negative, but expressed uPAR during differentiation in short-term liquid culture stimulated in vitro by recombinant interleukin (IL)-1, IL-3, IL-6, granulocyte-macrophage colony stimulating factor (CSF), granulocyte-CSF, and stem cell factor. Enhanced uPAR expression was also seen in HL-60 cells after induction of differentiation with dimethyl sulfoxide or 1 alpha,25-dihydroxyvitamin D3. In lymphomas and leukemias, the staining pattern was similar to that seen in the normal cells with labelling of monocytic and myeloid that seen in the normal cells with labelling of monocytic and myeloid malignancies, but not of the neoplastic cells in B-cell or T-cell lymphomas or Hodgkin's disease. In conclusion, uPAR is a differentiation marker for myeloid and monocytic cells, and may act to facilitate migration of these cells in normal and pathologic conditions by cell-associated plasminogen activation. Whether expression of uPAR in myeloid and monocytic malignancies relates to their growth and behavior will be an important topic for investigations in the future.


Assuntos
Células Sanguíneas/química , Medula Óssea/química , Leucemia Mieloide/sangue , Tecido Linfoide/química , Linfoma/química , Receptores de Superfície Celular/análise , Humanos , Receptores de Ativador de Plasminogênio Tipo Uroquinase
8.
Blood ; 83(3): 808-15, 1994 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8298141

RESUMO

The cellular receptor for urokinase-type plasminogen activator (uPAR) binds pro-urokinase (pro-uPA) and facilitates its conversion to enzymatically active urokinase (uPA). uPA in turn activates surface-bound plasminogen to plasmin, a process of presumed importance for a number of biologic processes including cell migration and resolution of thrombi. We have previously shown that uPAR is expressed on the plasma membrane of circulating neutrophils, and we now report that stimulation with phorbol myristate acetate (PMA), FMLP, or tumor necrosis factor-alpha results in a rapid increase in the expression of uPAR. This process is accompanied by an increased cell-associated plasminogen activation after preincubation of neutrophils with pro-uPA in vitro. By subcellular fractionation of unstimulated neutrophils, 50% of uPAR is recovered in fractions containing latent alkaline phosphatase, corresponding to an intracellular compartment of easily mobilizable secretory vesicles distinct from both primary and specific granules, whereas the remaining 50% of uPAR is associated with a compartment eluting close to the specific granules. In contrast, the ligand pro-uPA is primarily (approximately 80%) found in the specific granules, but small amounts of pro-uPA/uPA (approximately 20%) coelute with latent alkaline phosphatase. Stimulation of neutrophils with FMLP results in translocation of uPAR as well as of pro-uPA from the secretory vesicles, whereas stimulation with PMA is required to translocate material from specific granules. Flow cytometry of neutrophils saturated with exogenous diisopropyl fluorophosphate-uPA shows a large excess (approximately 90%) of unoccupied uPAR on resting as well as FMLP- and PMA-stimulated neutrophils, suggesting a possible role for exogenous pro-uPA in providing neutrophils with a potential for plasminogen activation. These processes may be important for neutrophil extravasation and migration through extracellular matrix and for the contribution of neutrophils to resolution of thrombi.


Assuntos
Neutrófilos/metabolismo , Receptores de Superfície Celular/metabolismo , Transporte Biológico/efeitos dos fármacos , Fracionamento Celular , Membrana Celular/metabolismo , Fibrinolisina/biossíntese , Citometria de Fluxo , Humanos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
9.
Am J Otolaryngol ; 10(5): 327-35, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2817248

RESUMO

Far-field vestibular responses to pulsed linear cranial acceleration have not been reported in detail for any species. In this study, precisely defined pulsed linear accelerations were used to elicit vestibular neural responses recorded from the surfaces of the skulls of 23 White Leghorn chicks. Traditional signal averaging techniques were used to resolve responses. At moderate intensities, responses consisted of a series of four to seven dominant peaks occurring within a period of 8 ms, having amplitudes between 0.3 and 20 microV peak-to-peak. The mean response threshold was 0.120 +/- 0.045 g. Latencies and amplitudes varied systematically as a function of stimulus intensity. Hypothermia prolonged response latencies. Response peaks did not invert on stimulus inversion, were present in response to cranial but not trunk acceleration, were not attenuated by broad-band auditory masking or by ambient light conditions, and disappeared with complete bilateral destruction of the labyrinth. The results rule out major contributions from auditory, somatosensory, and visual modalities and support the hypothesis that the responses reflect bilateral neural activity in the vestibular system. The findings suggest that direct noninvasive assessment of peripheral vestibular function can be achieved using pulsed linear acceleration stimuli.


Assuntos
Aceleração , Potenciais Somatossensoriais Evocados , Vestíbulo do Labirinto/fisiologia , Animais , Galinhas , Recrutamento Neurofisiológico/fisiologia
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