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1.
Artigo em Inglês | MEDLINE | ID: mdl-31586490

RESUMO

BACKGROUND: Secondary fungal infection is a major complication in patients with sepsis-associated immunosuppression. However, sepsis-induced immune alterations related to fungal susceptibility have not been well characterized. OBJECTIVES: To determine kinetic changes in the immune phenotype by determining the proportion of T cells, B cells and macrophages, and especially the expression of an immune exhaustion marker PD-1, in murine sepsis. In addition, sepsis -induced alterations of these immune cells were assessed in relation to susceptibility to secondary fungal infection. METHODS: Cecal ligation and puncture (CLP) was used as a mouse sepsis model, with Candida albicans as the secondary systemic fungal infection. Splenic T cells, B cells and macrophages were assessed by flow cytometry. RESULTS: Alterations in T cell and B cell numbers and the proportion of PD-1 expressing T cells and B cells in CLP mice were not clearly related to susceptibility to secondary Candida infection. By contrast, changes in levels of CD86+-activated macrophages, and the proportion of the PD-1+ population among the CD86+ macrophages in CLP mice were found to be related to secondary fungal infection susceptibility. CONCLUSIONS: Macrophage activation and exhaustion might be a significant determinant in susceptibility to fungal infection, and outcomes of infection. This study provided more comprehensive knowledge pertinent to patient evaluation and therapeutics design in restoring host defenses against secondary fungal infection in those with sepsis.

2.
J Exp Biol ; 222(Pt 22)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31636154

RESUMO

Naked mole-rats are one of the most hypoxia-tolerant mammals identified, and putatively experience intermittent and severe hypoxia in their underground burrows. Systemic physiological adaptions to hypoxia have begun to be investigated in this species; however, the cellular adaptations that underlie this tolerance remain poorly understood. Hypoxia compromises cellular energy production, and the maintenance of protein integrity when ATP generation is limited poses a major challenge. Heat shock proteins (HSPs) are cellular chaperones that are cytoprotective during hypoxia, and we hypothesized that their expression would increase during acute hypoxia in naked mole-rats. To test this hypothesis, we used qPCR and western blot approaches to measure changes in gene and protein expression, respectively, of HSP27, HSP40, HSP70 and HSP90 in the brain, heart, liver and temporalis muscle from naked mole-rats following exposure to normoxia (21% O2) or hypoxia (7% O2 for 4, 12 or 24 h). Contrary to our expectations, we observed significant global reductions of ATP-dependent HSP70 and HSP90 (83% and 78%, respectively) after 24 h of hypoxia. Conversely, the expression of ATP-independent HSP27 and HSP40 proteins remained constant throughout the 24-h hypoxic treatment in brain, heart and muscle. However, with prolonged hypoxia (24 h), the expression of Hsp27 and Hsp40 genes in these tissues was also reduced, suggesting that the protein expression of these chaperones may also eventually decrease in hypoxia. These results suggest that energy conservation is prioritized over cytoprotective protein chaperoning in naked mole-rat tissues during acute hypoxia. This unique adaptation may help naked mole-rats to minimize energy expenditure while still maintaining proteostasis in hypoxia.

3.
Shock ; 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31306346

RESUMO

BACKGROUND: Nosocomial aspergillosis in patients with sepsis have emerged in the past few years. Blockade of PD-1/PD-L pathway has tended to become a promising therapeutic strategy as it improved the outcome of bacterial sepsis and post-sepsis secondary fungal infection. Recently, the controversial effects of PD-1 blockade on infectious diseases, including aspergillosis, have been demonstrated, therefore, the efficacy of anti-PD-1 drug still remains to be elucidated. METHODS: Cecal ligation and puncture (CLP) was conducted as a mouse sepsis model. Aspergillus fumigatus spores were intravenously inoculated on day 5 post-CLP, when the immune cells succumbed to exhaustion. Amphotericin B was medicated together with or without anti-PD-1 treatment after Aspergillus infection. RESULTS: Amphotericin B alone was not effective to treat the CLP-mice with secondary aspergillosis. In contrast, anti-fungal medication with the adjunctive anti-PD-1 treatment attenuated the fungal burdens in blood and internal organs, and improved the survival rate of the mice with secondary aspergillosis. These outcomes of PD-1 blockade were concurring with the enhanced CD86 expression on splenocytes, the augmented serum IFN-γ and the dampened IL-10. Activated T cells from anti-PD-1 treated mice also highly increased IFN-γ and diminished IL-10 production. CONCLUSION: The blockade of PD-1 on post-sepsis aspergillosis presumably reinvigorated exhausted antigen-presenting cells and T cells by upregulating CD86 expression and IFN-γ production, and dampened IL-10 production, which consequently leaded to the attenuation of secondary aspergillosis. The adjunctive anti-PD-1 therapy may become a promising strategy for the advanced immunotherapy against lethal fungal infection.

4.
Bioresour Technol ; 281: 56-65, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30797175

RESUMO

This study examined the effects of a bacterial community and extracellular polymeric substances (EPS) on Ettlia sp. flocculation. The growth rate, flocculation efficiency (FE), bacterial community, and EPS profile of axenic and xenic Ettlia cultures were monitored during 46 days of cultivation. For the xenic culture, with a great abundance of growth-promoting and flocculation-inducing bacteria, the biomass density was 18.75% higher and its FE reached 100% in the mid-stationary phase. Moreover, microscopic observation and a quantitative analysis of the EPS revealed the exclusive presence of long filamentous EPS and more compact structure in the xenic Ettlia culture, possibly explaining its better FE. Notwithstanding, for the axenic culture, despite a lower biomass density and reduced abundance of EPS, its FE reached 92.54% in the mid-stationary phase. Thus, the role of the bacterial community was found to be supportive rather than vital for the high settleability of the self-flocculating Ettlia microalgal culture.


Assuntos
Clorofíceas/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Floculação , Microalgas/metabolismo , Microbiota , Microalgas/crescimento & desenvolvimento
5.
Am J Hematol ; 94(4): 467-474, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30697803

RESUMO

Although modern medical management has lowered overt stroke occurrence in patients with sickle cell disease (SCD), progressive white matter (WM) damage remains common. It is known that cerebral blood flow (CBF) increases to compensate for anemia, but sufficiency of cerebral oxygen delivery, especially in the WM, has not been systematically investigated. Cerebral perfusion was measured by arterial spin labeling in 32 SCD patients (age range: 10-42 years old, 14 males, 7 with HbSC, 25 HbSS) and 25 age and race-matched healthy controls (age range: 15-45 years old, 10 males, 12 with HbAS, 13 HbAA); 8/24 SCD patients were receiving regular blood transfusions and 14/24 non-transfused SCD patients were taking hydroxyurea. Imaging data from control subjects were used to calculate maps for CBF and oxygen delivery in SCD patients and their T-score maps. Whole brain CBF was increased in SCD patients with a mean T-score of 0.5 and correlated with lactate dehydrogenase (r2 = 0.58, P < 0.0001). When corrected for oxygen content and arterial saturation, whole brain and gray matter (GM) oxygen delivery were normal in SCD, but WM oxygen delivery was 35% lower than in controls. Age and hematocrit were the strongest predictors for WM CBF and oxygen delivery in patients with SCD. There was spatial co-localization between regions of low oxygen delivery and WM hyperintensities on T2 FLAIR imaging. To conclude, oxygen delivery is preserved in the GM of SCD patients, but is decreased throughout the WM, particularly in areas prone to WM silent strokes.


Assuntos
Anemia Falciforme , Circulação Cerebrovascular , Angiografia por Ressonância Magnética , Oxigênio/metabolismo , Substância Branca , Adolescente , Adulto , Anemia Falciforme/diagnóstico por imagem , Anemia Falciforme/metabolismo , Anemia Falciforme/fisiopatologia , Feminino , Hematócrito , Humanos , Masculino , Pessoa de Meia-Idade , Substância Branca/irrigação sanguínea , Substância Branca/diagnóstico por imagem , Substância Branca/metabolismo , Substância Branca/fisiopatologia
6.
Proc IEEE Int Symp Biomed Imaging ; 2018: 889-892, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30344893

RESUMO

White matter (WM) lesion identification and segmentation has proved of clinical importance for diagnosis, treatment and neurological outcomes. Convolutional neural networks (CNN) have demonstrated their success for large lesion load segmentation, but are not sensitive to small deep WM and sub-cortical lesion segmentation. We propose to use multi-scale and supervised fully convolutional networks (FCN) to segment small WM lesions in 22 anemic patients. The multiple scales enable us to identify the small lesions while reducing many false alarms, and the multi-supervised scheme allows a better management of the unbalanced data. Compared to a single FCN (Dice score ~0.31), the performance on the testing dataset of our proposed networks achieved a Dice score of 0.78.

7.
Proc IEEE Int Symp Biomed Imaging ; 2018: 1309-1312, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30344894

RESUMO

Long-term outcomes for Tetralogy of Fallot (TOF) have improved dramatically in recent years, but survivors are still afflicted by cerebral damage. In this paper, we characterized the prevalence and predictors of cerebral silent infarction (SCI) and their relationship to cerebral blood flow (CBF) in 46 adult TOF patients. We calculated both whole brain and regional CBF using 2D arterial spin labeling (ASL) images, and investigated the spatial overlap between voxel-wise CBF values and white matter hyperintensities (WMHs) identified from T2-FLAIR images. SCIs were found in 83% of subjects and were predicted by the year of the patient's first cardiac surgery and patient's age at scanning (combined r2 0.44). CBF was not different in brain regions prone to stroke compared with healthy white matter.

8.
BMC Microbiol ; 18(1): 85, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30119646

RESUMO

BACKGROUND: Gold nanoparticles (AuNP) have several biochemical advantageous properties especially for a candidate of drug carrier. However, the non-conjugated AuNP has a higher rate of cellular uptake than the conjugated ones. Spherical AuNP in a proper size (20-30 nm) is non-toxic to mice and shows anti-inflammatory properties. We tested if the administration of AuNP, as an adjuvant to antibiotics, could attenuate bacterial sepsis in cecal ligation and puncture (CLP) mouse model with antibiotic (imipenem/cilastatin). RESULTS: Indeed, AuNP administration at the time of CLP improved the survival, blood bacterial burdens, kidney function, liver injury and inflammatory cytokines (TNF-α, IL-6, IL-1ß and IL-10). AuNP also decreased M1 macrophages (CD86 + ve in F4/80 + ve cells) and increased M2 macrophages (CD206 + ve in F4/80 + ve cells) in the spleens of sepsis mice. The weak antibiotic effect of AuNP was demonstrated as the reduction of E. coli colony after 4 h incubation. In addition, AuNP altered cytokine production of bone-marrow-derived macrophages including reduced TNF-α, IL-6 and IL-1ß but increased IL-10 at 6 and 24 h. Moreover, AuNP induced macrophage polarization toward anti-inflammatory responses (M2) as presented by increased Arg1 (Arginase 1) and PPARγ with decreased Nos2 (inducible nitric oxide synthase, iNos) and Nur77 at 3 h after incubation in vitro. CONCLUSIONS: The adjuvant therapy of AuNP, with a proper antibiotic, attenuated CLP-induced bacterial sepsis in mice, at least in part, through the antibiotic effect and the induction of macrophage function toward the anti-inflammatory responses.


Assuntos
Antibacterianos/farmacologia , Ceco , Ouro/química , Ligadura/métodos , Macrófagos/imunologia , Nanopartículas Metálicas/química , Punções/métodos , Sepse/tratamento farmacológico , Animais , Arginase/metabolismo , Bactérias/patogenicidade , Doença Hepática Induzida por Substâncias e Drogas , Citocinas/metabolismo , Modelos Animais de Doenças , Escherichia coli/patogenicidade , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Rim/efeitos dos fármacos , Testes de Função Renal , Masculino , Camundongos , Óxido Nítrico Sintase Tipo II/metabolismo , Tamanho da Partícula , Sepse/microbiologia , Fator de Necrose Tumoral alfa/metabolismo
10.
Biotechnol Adv ; 36(2): 380-396, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29292155

RESUMO

The impact of microalgae (including blue-green algae or cyanobacteria) on human life can be both beneficiary and deleterious. While microalgae can be cultivated and used as feedstocks for the production of bioenergy and high value-added products in nutraceuticals, pharmaceuticals, and aquaculture feeds, some microalgae cause harmful algal blooms (HABs) that cause large-scale mortality in aquatic environments around the world. Thus, with the development of microalgal biotechnology and increasing concern about HABs, research on microscopic algae has increased significantly. However, this growth of academic research and application fields has been hindered by difficulties in obtaining axenic cultures. Therefore, this review provides a brief explanation of diverse establishment techniques, along with their strengths and weaknesses, with the hope of facilitating successful axenic cultures. A compilation of research fields and relevant important findings is also presented to clarify the importance of pure algal cultures. Finally, several controversial and sometimes overlooked issues related to the establishment, maintenance, and utilization of axenic cultures are discussed.


Assuntos
Cultura Axênica , Biotecnologia , Microalgas , Cianobactérias
11.
Pediatr Cardiol ; 38(5): 1010-1015, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28345114

RESUMO

Coronary artery re-implantation during arterial switch operation in patients with D-looped transposition of the great arteries (D-TGA) can alter coronary arterial flow and increase shear stress, leading to local endothelial dysfunction, although prior studies have conflicting results. Endothelial pulse amplitude testing can predict coronary endothelial dysfunction by peripheral arterial testing. This study tested if, compared to healthy controls, patients with D-TGA after arterial switch operation had peripheral endothelial dysfunction. Patient inclusion criteria were (1) D-TGA after neonatal arterial switch operation; (2) age 9-29 years; (3) absence of known cardiovascular risk factors such as hypertension, diabetes, hypercholesterolemia, vascular disease, recurrent vasovagal syncope, and coronary artery disease; and (4) ability to comply with overnight fasting. Exclusion criteria included (1) body mass index ≥85th percentile, (2) use of medications affecting vascular tone, or (3) acute illness. We assessed endothelial function by endothelial pulse amplitude testing and compared the results to our previously published data in healthy controls (n = 57). We tested 20 D-TGA patients (16.4 ± 4.8 years old) who have undergone arterial switch operation at a median age of 5 days (0-61 days). Endothelial pulse amplitude testing indices were similar between patients with D-TGA and controls (1.78 ± 0.61 vs. 1.73 ± 0.54, p = 0.73).In our study population of children and young adults, there was no evidence of peripheral endothelial dysfunction in patients with D-TGA who have undergone arterial switch operation. Our results support the theory that coronary arterial wall thickening and abnormal vasodilation reported in these patients is a localized phenomenon and not reflective of overall atherosclerotic burden.


Assuntos
Transposição das Grandes Artérias/efeitos adversos , Doença da Artéria Coronariana/fisiopatologia , Endotélio Vascular/fisiopatologia , Doenças Vasculares Periféricas/fisiopatologia , Transposição dos Grandes Vasos/cirurgia , Adolescente , Criança , Doença da Artéria Coronariana/etiologia , Vasos Coronários/fisiopatologia , Humanos , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/etiologia , Transposição dos Grandes Vasos/fisiopatologia , Adulto Jovem
12.
J Ocul Pharmacol Ther ; 33(3): 186-192, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28072560

RESUMO

PURPOSE: To investigate the therapeutic potential of a prostacyclin (IP) receptor agonist for ocular inflammation and the effect on immune cells. METHODS: The anti-inflammatory activities of cicaprost were determined in primary human monocyte-derived macrophages and human monocyte-derived dendritic cells (MoDC), as well as a lipopolysaccharides (LPS)-induced rat uveitis model. Multiple cytokine release was measured by utilizing Luminex Technology. Prostacyclin (IP) Receptor expression was detected by reverse transcription-polymerase chain receptor. Leukocyte infiltration and protein exudation in the rat uveitis model were measured using a hemocytometer and protein concentration by a NanoDrop instrument. RESULTS: Cicapost, an IP receptor agonist, potently inhibits proinflammatory chemokines/cytokine production not only from LPS- or TNFα (tumor necrosis factor-alpha)-induced primary human monocyte-derived macrophages, but also from LPS-stimulated MoDC. While constitutively expressed in macrophages, the IP receptor was inducible by LPS stimulation in MoDCs. In a LPS-induced rat uveitis model, cicaprost efficaciously prevents ocular inflammatory cell and protein leakage, as well as inflammatory cytokine release. CONCLUSION: The IP receptor agonist cicaprost is a potent anti-inflammatory agent, implicating that the tightly controlled PGI2/IP signaling pathway is important in regulating inflammation. This response could be harnessed in ocular inflammatory disease where steroids are currently the standard of care.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Células Dendríticas/efeitos dos fármacos , Modelos Animais de Doenças , Epoprostenol/análogos & derivados , Macrófagos/efeitos dos fármacos , Uveíte/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Células Dendríticas/metabolismo , Epoprostenol/administração & dosagem , Epoprostenol/farmacologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/metabolismo , Masculino , Ratos Endogâmicos Lew , Receptores de Epoprostenol/agonistas , Receptores de Epoprostenol/genética , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Uveíte/induzido quimicamente
13.
Artigo em Inglês | MEDLINE | ID: mdl-30344364

RESUMO

Sickle cell disease (SCD) is an inherited blood disorder that effects red blood cells, which can lead to vasoocclusion, ischemia and infarct. This disease often results in neurological damage and strokes, leading to morbidity and mortality. Functional Magnetic Resonance Imaging (fMRI) is a non-invasive technique for measuring and mapping the brain activity. Blood Oxygenation Level-Dependent (BOLD) signals contain also information about the neurovascular coupling, vascular reactivity, oxygenation and blood propagation. Temporal relationship between BOLD fluctuations in different parts of the brain provides also a mean to investigate the blood delay information. We used the induced desaturation as a label to profile transit times through different brain areas, reflecting oxygen utilization of tissue. In this study, we aimed to compare blood flow propagation delay times between these patients and healthy subjects in areas vascularized by anterior, middle and posterior cerebral arteries. In a group comparison analysis with control subjects, BOLD changes in these areas were found to be almost simultaneous and shorter in the SCD patients, because of their increased brain blood flow. Secondly, the analysis of a patient with a stenosis on the anterior cerebral artery indicated that signal of the area vascularized by this artery lagged the MCA signal. These findings suggest that sickle cell disease causes blood propagation modifications, and that these changes could be used as a biomarker of vascular damage.

14.
J Pediatr ; 167(3): 533-9.e1, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26154402

RESUMO

OBJECTIVE: To evaluate adherence of overweight and obese adolescents to a live video lifestyle intervention. The impact on vascular and functional health was also assessed. STUDY DESIGN: Twenty adolescents 14.5 ± 2.1 years of age with body mass index z-score 1.94 ± 0.43 were enrolled. The 12-week intervention included 3-times-weekly videoconference sessions with a trainer and weekly diet consultations. Adherence was evaluated by completion rate and percentage of sessions attended. Vascular health indices and traditional cardiovascular risk factors were obtained at baseline and study end. RESULTS: Seventeen participants (85%) completed the intervention. The participants attended 93 ± 11% of scheduled sessions. Reasons for absences included illness/injury (23%), school activities (21%), holidays (18%), forgetting the appointment (8%), Internet connectivity issues (7%), and family emergency (7%). Significant changes were observed in waist-hip ratio (0.87 ± 0.08 vs 0.84 ± 0.08, P = .03), total (159 ± 27 vs 147 ± 23 mg/dL, P = .004) and low-density lipoprotein cholesterol levels (91 ± 20 vs 81 ± 18 mg/dL, P = .004), volume of inspired oxygen per heartbeat at peak exercise (69 ± 16 vs 72 ± 15%, P = .01), and functional movement score (13 ± 2 vs 17 ± 1, P < .001). Participants with abnormal vascular function at baseline showed improvement in endothelial function and arterial stiffness indices (P = .01 and P = .04, respectively). CONCLUSIONS: A 12-week live video intervention promotes adherence among overweight and obese adolescents and shows promise for improving vascular and functional health. Integrating telehealth into preventive care has the potential to improve cardiovascular health in the youth at risk.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dietoterapia/métodos , Terapia por Exercício/métodos , Obesidade/terapia , Sobrepeso/terapia , Cooperação do Paciente , Adolescente , Comportamento do Adolescente , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Criança , Feminino , Humanos , Estilo de Vida , Lipídeos/sangue , Masculino , Fatores de Risco , Comunicação por Videoconferência , Adulto Jovem
15.
Artigo em Inglês | MEDLINE | ID: mdl-30344363

RESUMO

Sickle cell disease (SCD) is a hereditary blood disorder in which the oxygen-carrying hemoglobin molecule in red blood cells is abnormal. It affects numerous people in the world and leads to a shorter life span, pain, anemia, serious infections and neurocognitive decline. Tract-Specific Analysis (TSA) is a statistical method to evaluate white matter alterations due to neurocognitive diseases, using diffusion tensor magnetic resonance images. Here, for the first time, TSA is used to compare 11 major brain white matter (WM) tracts between SCD patients and age-matched healthy subjects. Alterations are found in the corpus callosum (CC), the cortico-spinal tract (CST), inferior fronto-occipital fasciculus (IFO), inferior longitudinal fasciculus (ILF), superior longitudinal fasciculus (SLF), and uncinated fasciculus (UNC). Based on previous studies on the neurocognitive functions of these tracts, the significant areas found in this paper might be related to several cognitive impairments and depression, both of which are observed in SCD patients.

16.
Neonatology ; 107(1): 20-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25301402

RESUMO

BACKGROUND: Use of non-invasive peripheral arterial tonometry to assess arterial stiffness has not been studied in neonates. Perinatal factors impact childhood vascular health, but the effect in neonates remains to be examined. OBJECTIVES: To examine the feasibility of pulse wave velocity (PWV) among healthy term neonates, and to evaluate the effects of perinatal factors on neonatal PWV. METHODS: Pregnant women with singleton gestation presenting for routine care were enrolled. Postnatally, PWV measurements of their neonates were obtained using an arterial tonometer. A variability index was calculated for each PWV measurement. Intra- and inter-observer reproducibility were illustrated with Bland-Altman plots. Medical records were reviewed. Relationships between neonatal PWV and perinatal factors were examined. RESULTS: PWV measurements were attempted in 76 neonates and successfully obtained in 67 (88%). Using PWV measurements with a variability index ≤ 0.25 (48 neonates), the intra-class coefficient was 0.69. The mean differences (limits of agreement) for intra- and inter-rater reproducibility were 0.02 (-3.64 to 3.60) and 0.34 (-2.23 to 2.39), respectively. Median neonatal PWV was 2.80 m/s (range 0.60-8.40). Neonates of mothers with HgbA1c ≥6% had significantly higher PWV than neonates of mothers with HgbA1c <6% (4.12 m/s, 95% CI 3.22-5.02, vs. 2.78 m/s, 95% CI 2.28-3.28, p = 0.02). CONCLUSIONS: Neonatal PWV using peripheral arterial tonometry is feasible and reproducible when using measurements with a variability index ≤ 0.25. Neonates of mothers with increased HgbA1c had higher PWV, suggesting an effect of maternal hyperglycemia on neonatal vasculature. The long-term implications of this finding warrant further investigation.


Assuntos
Hemoglobina A Glicada/análise , Hiperglicemia , Complicações na Gravidez , Análise de Onda de Pulso/métodos , Rigidez Vascular , Adulto , Artérias/fisiopatologia , Estudos de Viabilidade , Feminino , Humanos , Hiperglicemia/diagnóstico , Hiperglicemia/etiologia , Hiperglicemia/fisiopatologia , Hiperglicemia/prevenção & controle , Saúde do Lactente , Recém-Nascido , Manometria/métodos , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/fisiopatologia , Complicações na Gravidez/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal , Estatística como Assunto
17.
J Agric Food Chem ; 62(29): 7263-7, 2014 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-24979322

RESUMO

Visual oxygen indicators can give information on the quality and safety of packaged food in an economic and simple manner by changing color based on the amount of oxygen in the packaging, which is related to food spoilage. In particular, ultraviolet (UV)-activated oxygen indicators have the advantages of in-pack activation and irreversibility; however, these dye-based oxygen indicator films suffer from dye leaching upon contact with water. In this work, we introduce carrageenans, which are natural sulfated polysaccharides, to develop UV-activated colorimetric oxygen indicator films that are resistant to dye leakage. Carrageenan-based indicator films were fabricated using redox dyes [methylene blue (MB), azure A, and thionine], a sacrificial electron donor (glycerol), an UV-absorbing photocatalyst (TiO2), and an encapsulation polymer (carrageenan). They showed even lower dye leakage in water than conventional oxygen indicator films, owing to the electrostatic interaction of anionic carrageenan with cationic dyes. The MB/TiO2/glycerol/carrageenan oxygen indicator film was successfully bleached upon UV irradiation, and it regained color very rapidly in the presence of oxygen compared to the other waterproof oxygen indicator films.


Assuntos
Carragenina/química , Colorimetria/métodos , Embalagem de Alimentos , Oxigênio/análise , Espectrofotometria Ultravioleta
18.
Am J Hypertens ; 27(9): 1218-24, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24627445

RESUMO

BACKGROUND: Aortic pulse wave velocity (PWV) and augmentation index (AIx) are markers of vascular health and have recently been used in pediatric clinical trials. However, there are limited data on standardization of these measurements in pediatrics. The objective of this study was to prospectively test the feasibility and reproducibility of PWV and AIx in children and adolescents. METHODS: We performed arterial tonometry on 2 different days within 2 weeks in 40 healthy subjects aged 10-19 years. PWV and AIx were measured in triplicate on each visit. RESULTS: The visits were separated by a mean of 3.08±3.7 days. We obtained PWV in 77 of 80 (96%) visits and AIx in 76 of 80 (95%) visits in triplicate. Intraclass correlation coefficients (ICCs) for PWV were 0.61 (95% confidence interval (CI) = 0-0.86) when at least 2 measurements and 0.92 (95% CI = 0-1) when 3 measurements were obtained at each visit that met the quality criteria established for adults by the manufacturer (n = 17 and 3 paired visits, respectively). For AIx, ICCs were 0.78 (95% CI = 0.58-0.88) and 0.81 (95% CI = 0.63-0.90) when measurements with an operator index ≥80, a measure of the quality of the waveform, were included (n = 39 and 36 paired visits, respectively). CONCLUSIONS: Arterial applanation tonometry is feasible and reproducible in healthy children and adolescents. AIx has excellent intervisit reproducibility, whereas the intervisit reproducibility of PWV relies on acquisition of multiple measurements that meet quality criteria established for adults. These results have implications for the methodology of future pediatric clinical trials in a population at increasingly higher risk for premature atherosclerosis.


Assuntos
Artérias/fisiologia , Hemodinâmica , Manometria/métodos , Análise de Onda de Pulso/métodos , Adolescente , Fatores Etários , Criança , Estudos de Viabilidade , Feminino , Voluntários Saudáveis , Humanos , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
19.
Food Chem ; 140(1-2): 52-6, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23578614

RESUMO

For the first time, alginate polymer has been applied to prevent dyes from leaching out of colorimetric oxygen indicator films, which enable people to notice the presence of oxygen in the package in an economic and simple manner. The dye-based oxygen indicator film suffers from dye leaching upon contact with water. In this work, UV-activated visual oxygen indicator films were fabricated using thionine, glycerol, P25 TiO2, and zein as a redox dye, a sacrificial electron donor, UV-absorbing semiconducting photocatalyst, and an encapsulation polymer, respectively. When this zein-coated film was immersed in water for 24h, the dye leakage was as high as 80.80±0.45%. However, introduction of alginate (1.25%) as the coating polymer considerably diminished the dye leaching to only 5.80±0.06%. This is because the ion-binding ability of alginate could prevent the cation dye from leaching into water. This novel water-resistant UV-activated oxygen indicator was also successfully photo-bleached and regained colour fast in the presence of oxygen.


Assuntos
Embalagem de Alimentos/instrumentação , Oxigênio/química , Alginatos/química , Corantes/química , Embalagem de Alimentos/métodos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Indicadores e Reagentes/efeitos da radiação , Raios Ultravioleta , Água/análise
20.
Biotechnol Prog ; 29(2): 513-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23335471

RESUMO

Mussels can attach themselves to nearly all types of hard surfaces in wet environments. Such attractive adhesive ability of mussels is believed to rely on the amino acid composition of proteins found near the plaque-substrate interface. Dopamine (DA) is identified as a simplified mimic of mussel proteins, which are rich in 3,4-dihydroxy-L-phenylalanine and lysine, because it contains both catechol and amine functional groups. In this work, we have first applied this bioinspired adhesive to tackle a dye leaching problem of colorimetric oxygen indicator films, which are widely used to ensure the absence of oxygen inside the package of oxygen-sensitive materials. Simple immersion of packaging films into a DA solution resulted in poly(DA) deposition, decreasing the water contact angle of the films from 105° to 65°. The poly(DA) coating could reduce the thionine leakage of the UV-activated oxygen indicator film. The effects of poly(DA) coating were found to be dependent on the DA solution pH, the coating time, and the DA concentration. The film resistant to dye leaching lost its dye color by 5 min UVB irradiation and regained the color in the presence of oxygen, demonstrating that it functioned successfully as UV-activated oxygen indicators.


Assuntos
Dopamina/química , Embalagem de Alimentos/instrumentação , Animais , Bivalves/citologia , Moléculas de Adesão Celular/química , Oxigênio/química , Propriedades de Superfície , Água/metabolismo
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