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1.
Chemosphere ; 329: 138531, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37004818

RESUMO

Water is an essential resource for humans, animals, and plants. Water is also necessary for the manufacture of many products such as milk, textiles, paper, and pharmaceutical composites. During manufacturing, some industries generate a large amount of wastewater containing numerous contaminants. In the dairy industry, for each litre of drinking milk produced, about 10 L of wastewater is generated. Despite this environmental footprint, the production of milk, butter, ice cream, baby formula, etc., are essential in many households. Common contaminants in dairy wastewater include high biological oxygen demand (BOD), chemical oxygen demand (COD), salts as well as nitrogen and phosphorus derivatives. Nitrogen and phosphorus discharges are one of the leading causes in the eutrophication of rivers and oceans. Porous materials have long held significant potential as a disruptive technology for wastewater treatment. However, thus far they have been understudied for use in dairy wastewater treatment. Ordered porous materials, such as zeolites and metal organic frameworks (MOFs), represent classes of porous materials with significant potential for the removal of nitrogen and phosphorus. This review explores the different zeolites and MOFs applied in the removal of nitrogen and phosphorus from wastewater and the prospect of their potential for use in wastewater management in the dairy industry.


Assuntos
Estruturas Metalorgânicas , Purificação da Água , Zeolitas , Animais , Humanos , Águas Residuárias , Fósforo , Nitrogênio/análise , Purificação da Água/métodos , Água , Eliminação de Resíduos Líquidos/métodos
2.
Brain Behav Immun Health ; 24: 100491, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35873350

RESUMO

Background: As the coronavirus disease 2019 (COVID-19) pandemic continues, there has been a growing interest in the chronic sequelae of COVID-19. Neuropsychiatric symptoms are observed in the acute phase of infection, but there is a need for accurate characterization of how these symptoms evolve over time. Additionally, African American populations have been disproportionately affected by the COVID-19 pandemic. The COVID-19 Neurological and Molecular Prospective Cohort Study in Georgia (CONGA) was established to investigate the severity and chronicity of these neurologic findings over the five-year period following infection. Methods: The CONGA study aims to recruit COVID-19 positive adult patients in Georgia, United States from both the inpatient and outpatient setting, with 50% being African American. This paper reports our preliminary results from the baseline visits of the first 200 patients recruited who were on average 125 days since having a positive COVID-19 test. The demographics, self-reported symptoms, comorbidities, and quantitative measures of depression, anxiety, smell, taste, and cognition were analyzed. Cognitive measures were compared to demographically matched controls. Blood and mononuclear cells were drawn and stored for future analysis. Results: Fatigue was the most reported symptom in the study cohort (68.5%). Thirty percent of participants demonstrated hyposmia and 30% of participants demonstrated hypogeusia. Self-reported neurologic dysfunction did not correlate with dysfunction on quantitative neurologic testing. Additionally, self-reported symptoms and comorbidities were associated with depression and anxiety. The study cohort performed worse on cognitive measures compared to demographically matched controls, and African American patients scored lower compared to non-Hispanic White patients on all quantitative cognitive testing. Conclusion: Our results support the growing evidence that there are chronic neuropsychiatric symptoms following COVID-19 infection. Our results suggest that self-reported neurologic symptoms do not appear to correlate with associated quantitative dysfunction, emphasizing the importance of quantitative measurements in the complete assessment of deficits. Self-reported symptoms are associated with depression and anxiety. COVID-19 infection appears to be associated with worse performance on cognitive measures, though the disparity in score between African American patients and non-Hispanic White patients is likely largely due to psychosocial, physical health, and socioeconomic factors.

3.
Mater Sci Eng C Mater Biol Appl ; 120: 111657, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33545824

RESUMO

Core-shell scaffolds offer a promising regenerative solution to debilitating injuries to anterior cruciate ligament (ACL) thanks to a unique biphasic structure. Nevertheless, current core-shell designs are impaired by an imbalance between permeability, biochemical and mechanical cues. This study aimed to address this issue by creating a porous core-shell construct which favors cell infiltration and matrix production, while providing mechanical stability at the site of injury. The developed core-shell scaffold combines an outer shell of electrospun poly(caprolactone) fibers with a freeze-dried core of type I collagen doped with proteoglycans (biglycan, decorin) or glycosaminoglycans (chondroitin sulphate, dermatan sulphate). The aligned fibrous shell achieved an elastic modulus akin of the human ACL, while the porous collagen core is permeable to human mesenchymal stem cell (hMSC). Doping of the core with the aforementioned biomolecules led to structural and mechanical changes in the pore network. Assessment of cellular metabolic activity and scaffold contraction shows that hMSCs actively remodel the matrix at different degrees, depending on the core's doping formulation. Additionally, immunohistochemical staining and mRNA transcript levels show that the collagen-chondroitin sulphate formulation has the highest matrix production activity, while the collagen-decorin formulation featured a matrix production profile more characteristic of the undamaged tissue. Together, this demonstrates that scaffold doping with target biomolecules leads to distinct levels of cell-mediated matrix remodeling. Overall, this work resulted in the development of a versatile and robust platform with a combination of mechanical and biochemical features that have a significant potential in promoting the repair process of ACL tissue.


Assuntos
Glicosaminoglicanos , Alicerces Teciduais , Colágeno , Humanos , Poliésteres , Engenharia Tecidual
4.
Biomaterials ; 269: 120651, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33476892

RESUMO

This study addresses a crucial gap in the literature by characterising the relationship between urethral tissue mechanics, composition and gross structure. We then utilise these data to develop a biomimetic urethral scaffold with physical properties that more accurately mimic the native tissue than existing gold standard scaffolds; small intestinal submucosa (SIS) and urinary bladder matrix (UBM). Nine human urethra samples were mechanically characterised using pressure-diameter and uniaxial extension testing. The composition and gross structure of the tissue was determined using immunohistological staining. A pressure stiffening response is observed during the application of intraluminal pressure. The elastic and viscous tissue responses to extension are free of regional or directional variance. The elastin and collagen content of the tissue correlates significantly with tissue mechanics. Building on these data, a biomimetic urethral scaffold was fabricated from collagen and elastin in a ratio that mimics the composition of the native tissue. The resultant scaffold is comprised of a dense inner layer and a porous outer layer that structurally mimic the submucosa and corpus spongiosum layers of the native tissue, respectively. The porous outer layer facilitated more uniform cell infiltration relative to SIS and UBM when implanted subcutaneously (p < 0.05). The mechanical properties of the biomimetic scaffold better mimic the native tissue compared to SIS and UBM. The tissue characterisation data presented herein paves the way for the development of biomimetic urethral grafts, and the novel scaffold we develop demonstrates positive findings that warrant further in vivo evaluation.


Assuntos
Biomimética , Uretra , Colágeno , Humanos , Masculino , Engenharia Tecidual , Alicerces Teciduais
5.
Acta Biomater ; 112: 52-61, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32525053

RESUMO

This article describes the development of a hierarchical biofabrication technique suitable to create large but complex structures, such as vascular mimicking grafts, using facile lyophilisation technology amenable to multiple other biomaterial classes. The combination of three fabrication techniques together, namely solvent evaporation, lyophilisation, and crosslinking together allows highly tailorable structures from the microstructure up to the macrostructure, and with the ability to independently crosslink each layer it allows great flexibility to match desired native mechanical properties independently of the micro/macrostructure. We have demonstrated the flexibility of this biofabrication technique by independently optimising each of the layers to create a multi-layered arterial structure with tailored architectural and biophysical/biochemical properties using a collagen-elastin composite. Taken together, the facile biofabrication methodology developed has led to the development of a biomimetic bilayered scaffold suitable for use as a tissue engineered vascular graft (for haemodialysis access or peripheral/coronary bypass), or as an in vitro test platform to examine disease progression, pharmacological toxicity, or cardiovascular medical device testing. STATEMENT OF SIGNIFICANCE: The ability to grow large complex tissues such as blood vessels for transplantation is often hampered by the limitations of the selected biofabrication technique. Here, we sought to overcome some of the fabrication limitations for naturally occurring cardiovascular polymers (collagen/elastin) via a hierarchical approach to fabrication where each layer is built upon the previous. This approach enabled the flexibility to modify and tailor each layer's properties independently via control over polymer concentration, microstructure, and crosslinking. This simple approach facilitated us to fabricate multi-layered vascular grafts which were remodelled into high-density vascular tissue after 21-days. The fabrication approach could be translated to a myriad of other tissues while the engineered vascular graft could also be used as a test platform for drugs/medical devices or as a tissue engineering scaffold for vascular grafting for different indications.


Assuntos
Elastina , Enxerto Vascular , Biomimética , Prótese Vascular , Colágeno , Engenharia Tecidual , Alicerces Teciduais
6.
Kidney360 ; 1(11): 1284-1290, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-35372879

RESUMO

Background: Hyperoxaluria is typically associated with excessive oxalate intake in the diet, decreased dietary calcium, hyperabsorption of oxalate, or increased endogenous production of oxalate. The disorder spectrum extends from recurrent kidney stones to ESKD. This clinical trial sought to evaluate the effectiveness of an acid stable oxalate decarboxylase (OxDC) to reduce urinary oxalate in healthy subjects on a high-oxalate diet. Methods: In this prospective, double-blind, randomized, placebo-controlled, crossover clinical trial, 33 healthy volunteers were randomized into two crossover sequences separated by a 2-day washout period. A controlled high-oxalate diet (750-800 mg oxalate, 500-550 mg calcium daily) was utilized, and six 24-hour urine collections were measured. Subjects were given approximately 1000 U (micromoles per minute per milligram) of OxDC or placebo with meals three times daily during the 4 days of treatment. Results: Urinary oxalate significantly decreased with OxDC treatment. The baseline corrected within-subject mean reduction in 24-hour urinary excretion (after OxDC dosing versus high-oxalate baseline preceding treatment) was 12.5 mg or 29% (P<0.001). OxDC treatment was effective (>5% reduction) in 31 of 33 subjects (94%). Compared with placebo, OxDC produced a 24% reduction (P<0.001) in 24-hour oxalate excretion. Other urinary parameters (creatinine, uric acid, citrate, magnesium, calcium) were not affected by OxDC. No serious adverse events and no product-related adverse events occurred. Conclusions: An orally administered OxDC is capable of significantly reducing urinary oxalate levels in healthy volunteers on a high-oxalate diet without affecting creatinine clearance, urine creatinine, or other solutes related to supersaturation of calcium oxalate. Clinical Trial registry name and registration number: Evaluation of Nephure, and the Reduction of Dietary Oxalate, in Healthy Volunteers, NCT03661216.


Assuntos
Carboxiliases , Cálculos Renais , Estudos Cross-Over , Humanos , Cálculos Renais/tratamento farmacológico , Estudos Prospectivos
7.
Hematol Oncol Clin North Am ; 33(4): 553-574, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229154

RESUMO

Mature B- and T-cell lymphomas are diverse in their biology, etiology, genetics, clinical behavior, and response to specific therapies. Here, we review the principles of diagnostic classification for non-Hodgkin lymphomas, summarize the characteristic features of major entities, and place recent biological and molecular findings in the context of principles that are applicable across the spectrum of mature lymphoid cancers.


Assuntos
Linfoma de Células B , Linfoma de Células T , Linfócitos B/metabolismo , Linfócitos B/patologia , Proliferação de Células/genética , Humanos , Linfoma de Células B/classificação , Linfoma de Células B/genética , Linfoma de Células B/patologia , Linfoma de Células T/classificação , Linfoma de Células T/genética , Linfoma de Células T/patologia , Gradação de Tumores , Linfócitos T/metabolismo , Linfócitos T/patologia
8.
Biomaterials ; 197: 405-416, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30708184

RESUMO

The bone infection osteomyelitis (typically by Staphylococcus aureus) usually requires a multistep procedure of surgical debridement, long-term systemic high-dose antibiotics, and - for larger defects - bone grafting. This, combined with the alarming rise in antibiotic resistance, necessitates development of alternative approaches. Herein, we describe a one-step treatment for osteomyelitis that combines local, controlled release of non-antibiotic antibacterials with a regenerative collagen-based scaffold. To maximise efficacy, we utilised bioactive glass, an established osteoconductive material with immense capacity for bone repair, as a delivery platform for copper ions (proven antibacterial, angiogenic, and osteogenic properties). Multifunctional collagen-copper-doped bioactive glass scaffolds (CuBG-CS) were fabricated with favourable microarchitectural and mechanical properties (up to 1.9-fold increase in compressive modulus over CS) within the ideal range for bone tissue engineering. Scaffolds demonstrated antibacterial activity against Staphylococcus aureus (up to 66% inhibition) whilst also enhancing osteogenesis (up to 3.6-fold increase in calcium deposition) and angiogenesis in vitro. Most significantly, when assessed in a chick embryo in vivo model, CuBG-CS not only demonstrated biocompatibility, but also a significant angiogenic and osteogenic response, consistent with in vitro studies. Collectively, these results indicate that the CuBG-CS developed here show potential as a one-step osteomyelitis treatment: reducing infection, whilst enhancing bone healing.


Assuntos
Indutores da Angiogênese/administração & dosagem , Antibacterianos/administração & dosagem , Colágeno/química , Cobre/administração & dosagem , Osteogênese/efeitos dos fármacos , Alicerces Teciduais/química , Indutores da Angiogênese/farmacologia , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Linhagem Celular , Embrião de Galinha , Cobre/farmacologia , Sistemas de Liberação de Medicamentos , Vidro/química , Camundongos , Neovascularização Fisiológica/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos
9.
J Am Osteopath Assoc ; 118(12): 806-811, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30476992

RESUMO

Osteopathic medicine is continuing to move toward competency-based education at undergraduate and graduate levels. Competencies and Entrustable Professional Activities (EPAs) have been implemented to guide educators on the skills and abilities that osteopathic medical students and residents should be able to perform as physicians. Unfortunately, many of these skills have not been well described, and the threshold of "competence" or "entrustability" for each of these tasks remains elusive. The author presents an approach to measuring competence in the domain of osteopathic manipulative medicine using a milestone rubric to assess skills related to osteopathic screening, diagnosis, technique, and explanation. This rubric can be applied to all levels of osteopathic training and across many diagnostic and treatment modalities. Clearly defining and assessing the individual skills composing competence in osteopathic manipulative medicine will be increasingly important as medical education continues to evolve and modernize.


Assuntos
Competência Clínica , Internato e Residência , Medicina Osteopática/educação , Educação Baseada em Competências , Humanos
10.
J Food Prot ; 81(7): 1108-1116, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29916731

RESUMO

Microbiological hazards can occur when foodstuffs come into contact with contaminated surfaces or infectious agents dispersed by air currents in the manufacturing environment. An environmental monitoring program (EMP) is a critical aspect of sustainable and safe food manufacturing used to evaluate the effectiveness of the microbial controls in place. An effective EMP should be based on risk analysis, taking into account previous sampling history to determine the selection of the sampling points, the scope of the test, and the frequency of analysis. This study involved evaluation of the environmental monitoring regime and microbiological status of a medium-sized dairy plant manufacturing food ingredients, e.g., proteins, milk powders, and dairy fats. The data specific to microbial tests ( n = 3,468), recorded across 124 fixed sampling locations over a 2-year period (2014 to 2015) from air ( n = 1,787) and surfaces ( n = 1,681) were analyzed. The aim of this study was to highlight the strengths and weaknesses of the EMP in a select dairy processing plant. The results of this study outline the selection of sampling locations, the scope of the test, and the frequency of analysis. An analysis of variance revealed subsections of the manufacturing areas with high risk factors, especially the packaging subsection specified for bulk packaging, the atomizer, and the fluidized bed. The temporal and spatial analysis showed the potential to reduce or relocate the monitoring effort, most notably related to total coliforms and Staphylococcus aureus, across the dairy plant due to homogeneity across the sampling subsections with little or no deviations. The results suggest a need to reevaluate the current EMP and the corrective action plan, especially with regard to detection of pathogens. Recommendations for optimization of the EMP are presented to assist the dairy industry with reviewing and revising the control measures and hazard assessment with regard to existing contamination issues.


Assuntos
Microbiologia do Ar , Indústria de Laticínios , Monitoramento Ambiental , Indústria de Processamento de Alimentos , Contaminação de Equipamentos , Contaminação de Alimentos
11.
Adv Mater ; 30(15): e1706442, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29504165

RESUMO

Electroconductive substrates are emerging as promising functional materials for biomedical applications. Here, the development of biohybrids of collagen and pristine graphene that effectively harness both the biofunctionality of the protein component and the increased stiffness and enhanced electrical conductivity (matching native cardiac tissue) obtainable with pristine graphene is reported. As well as improving substrate physical properties, the addition of pristine graphene also enhances human cardiac fibroblast growth while simultaneously inhibiting bacterial attachment (Staphylococcus aureus). When embryonic-stem-cell-derived cardiomyocytes (ESC-CMs) are cultured on the substrates, biohybrids containing 32 wt% graphene significantly increase metabolic activity and cross-striated sarcomeric structures, indicative of the improved substrate suitability. By then applying electrical stimulation to these conductive biohybrid substrates, an enhancement of the alignment and maturation of the ESC-CMs is achieved. While this in vitro work has clearly shown the potential of these materials to be translated for cardiac applications, it is proposed that these graphene-based biohybrid platforms have potential for a myriad of other applications-particularly in electrically sensitive tissues, such as neural and neural and musculoskeletal tissues.


Assuntos
Materiais Biocompatíveis/química , Colágeno , Condutividade Elétrica , Grafite , Humanos , Miócitos Cardíacos
12.
Adv Healthc Mater ; 6(24)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28975768

RESUMO

Clinically available hollow nerve guidance conduits (NGCs) have had limited success in treating large peripheral nerve injuries. This study aims to develop a biphasic NGC combining a physicochemically optimized collagen outer conduit to bridge the transected nerve, and a neuroconductive hyaluronic acid-based luminal filler to support regeneration. The outer conduit is mechanically optimized by manipulating crosslinking and collagen density, allowing the engineering of a high wall permeability to mitigate the risk of neuroma formation, while also maintaining physiologically relevant stiffness and enzymatic degradation tuned to coincide with regeneration rates. Freeze-drying is used to seamlessly integrate the luminal filler into the conduit, creating a longitudinally aligned pore microarchitecture. The luminal stiffness is modulated to support Schwann cells, with laminin incorporation further enhancing bioactivity by improving cell attachment and metabolic activity. Additionally, this biphasic NGC is shown to support neurogenesis and gliogenesis of neural progenitor cells and axonal outgrowth from dorsal root ganglia. These findings highlight the paradigm that a successful NGC requires the concerted optimization of both a mechanical support phase capable of bridging a nerve defect and a neuroconductive phase with an architecture capable of supporting both Schwann cells and neurons in order to achieve functional regenerative outcome.


Assuntos
Regeneração Nervosa , Nervos Periféricos/cirurgia , Próteses e Implantes , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Colágeno/química , Gânglios Espinais/metabolismo , Laminina/metabolismo , Masculino , Neurogênese , Fenobarbital/química , Ratos , Ratos Endogâmicos Lew , Células de Schwann/metabolismo , Engenharia Tecidual
13.
Curr Opin Pharmacol ; 36: 66-71, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28865291

RESUMO

Islet transplantation for the treatment of type 1 diabetes (T1D) is hampered by the shortage of donor tissue and the need for life-long immunosuppression. The engineering of materials to limit host immune rejection opens the possibilities of utilising allogeneic and even xenogeneic cells without the need for systemic immunosuppression. Here we discuss the most recent developments in immunoisolation of transplanted cells using advanced polymeric biomaterials, utilising macroscale to nanoscale approaches, to limit aberrant immune responses.


Assuntos
Reação a Corpo Estranho/prevenção & controle , Transplante das Ilhotas Pancreáticas/instrumentação , Animais , Corpos Estranhos , Humanos , Ilhotas Pancreáticas , Polímeros/administração & dosagem , Polímeros/química
14.
Stem Cells Transl Med ; 6(10): 1894-1904, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28960910

RESUMO

Peripheral nerve injury presents significant therapeutic challenges for recovery of motor and sensory function in patients. Different clinical approaches exist but to date there has been no consensus on the most effective method of treatment. Here, we investigate a novel approach to peripheral nerve repair using olfactory derived stem (ONS) cells delivered in a biphasic collagen and laminin functionalized hyaluronic acid based nerve guidance conduit (NGC). Nerve regeneration was studied across a 10-mm sciatic nerve gap in Sprague Dawley rats. The effect of ONS cell loading of NGCs with or without nerve growth factor (NGF) supplementation on nerve repair was compared to a cell-free NGC across a variety of clinical, functional, electrophysiological, and morphologic parameters. Animals implanted with ONS cell loaded NGCs demonstrated improved clinical and electrophysiological outcomes compared to cell free NGC controls. The nerves regenerated across ONS cell loaded NGCs contained significantly more axons than cell-free NGCs. A return of the nocioceptive withdrawal reflex in ONS cell treated animals indicated an advanced repair stage at a relatively early time point of 8 weeks post implantation. The addition of NGF further improved the outcomes of the repair indicating the potential beneficial effect of a combined stem cell/growth factor treatment strategy delivered on NGCs. Stem Cells Translational Medicine 2017;6:1894-1904.


Assuntos
Regeneração Tecidual Guiada/métodos , Células Neuroepiteliais/transplante , Traumatismos dos Nervos Periféricos/terapia , Transplante de Células-Tronco/métodos , Animais , Células Cultivadas , Colágeno/química , Ácido Hialurônico/química , Laminina/química , Regeneração Nervosa , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/lesões , Alicerces Teciduais/química
15.
ACS Biomater Sci Eng ; 3(7): 1221-1235, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-33440511

RESUMO

Peripheral nerve injuries have high incidence rates, limited treatment options and poor clinical outcomes, rendering a significant socioeconomic burden. For effective peripheral nerve repair, the gap or site of injury must be structurally bridged to promote correct reinnervation and functional regeneration. However, effective repair becomes progressively more difficult with larger gaps. Autologous nerve grafting remains the best clinical option for the repair of large gaps (20-80 mm) despite being associated with numerous limitations including permanent donor site morbidity, a lack of available tissue and the formation of neuromas. To meet the clinical demand of large gap repair and overcome these limitations, tissue engineering has led to the development of nerve guidance conduit-based therapeutics. This review focuses on the advances of nerve guidance conduit-based therapeutics in terms of their structural properties including biomimetic composition, permeability, architecture, and surface modifications. Associated biochemical properties, pertaining to the incorporation of cells and neurotrophic factors, are also reviewed. After reviewing the progress in the field, we conclude by presenting an outlook on their clinical translatability and the next generation of therapeutics.

16.
Nutrients ; 8(4): 216, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27077882

RESUMO

Arachidonic acid (ARA, 20:4n-6) is an n-6 polyunsaturated 20-carbon fatty acid formed by the biosynthesis from linoleic acid (LA, 18:2n-6). This review considers the essential role that ARA plays in infant development. ARA is always present in human milk at a relatively fixed level and is accumulated in tissues throughout the body where it serves several important functions. Without the provision of preformed ARA in human milk or infant formula the growing infant cannot maintain ARA levels from synthetic pathways alone that are sufficient to meet metabolic demand. During late infancy and early childhood the amount of dietary ARA provided by solid foods is low. ARA serves as a precursor to leukotrienes, prostaglandins, and thromboxanes, collectively known as eicosanoids which are important for immunity and immune response. There is strong evidence based on animal and human studies that ARA is critical for infant growth, brain development, and health. These studies also demonstrate the importance of balancing the amounts of ARA and DHA as too much DHA may suppress the benefits provided by ARA. Both ARA and DHA have been added to infant formulas and follow-on formulas for more than two decades. The amounts and ratios of ARA and DHA needed in infant formula are discussed based on an in depth review of the available scientific evidence.


Assuntos
Ácido Araquidônico/metabolismo , Desenvolvimento Infantil , Leite Humano/química , Necessidades Nutricionais , Ácidos Docosa-Hexaenoicos/metabolismo , Humanos , Lactente
17.
Drug Discov Today ; 21(9): 1437-1445, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27117348

RESUMO

The field of tissue engineering is developing biomimetic biomaterial scaffolds that are showing increasing therapeutic potential for the repair of cardiovascular tissues. However, a major opportunity exists to use them as 3D in vitro models for the study of cardiovascular tissues and disease in addition to drug development and testing. These in vitro models can span the gap between 2D culture and in vivo testing, thus reducing the cost, time, and ethical burden of current approaches. Here, we outline the progress to date and the requirements for the development of ideal in vitro 3D models for blood vessels, heart valves, and myocardial tissue.


Assuntos
Vasos Sanguíneos , Valvas Cardíacas , Modelos Biológicos , Miocárdio , Animais , Doenças Cardiovasculares , Humanos , Engenharia Tecidual
18.
Nutr J ; 15: 42, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27103229

RESUMO

Considerable advances have been made in the field of infant feeding research. The last few decades have witnessed the expansion in the number of studies on the composition and benefits of human milk. The practice of breastfeeding and use of human milk represent today's reference standards for infant feeding and nutrition. Additional research regarding the benefits of breastfeeding is needed to determine which factors in human milk and in the act of breastfeeding itself, singly or in combination, are most important for producing the beneficial effects on infant growth, body composition, and neurodevelopmental outcome. We examine evidence that breastfeeding confers health benefits and offer suggestions on how best to interpret the data and present it to the public. We also describe some examples of well-designed infant nutrition studies that provide useful and clinically meaningful data regarding infant feeding, growth, and development. Because not all mothers choose to breastfeed or can breastfeed, other appropriate feeding options should be subjected to critical review to help establish how infant formula and bottle feeding can confer benefits similar to those of human milk and the act of breastfeeding. We conclude with the overarching point that the goal of infant feeding research is to promote optimal infant growth and development. Since parents/families may take different paths to feeding their infants, it is fundamental that health professionals understand how best to interpret research studies and their findings to support optimal infant growth and development.


Assuntos
Alimentação com Mamadeira , Aleitamento Materno , Fenômenos Fisiológicos da Nutrição do Lactente , Humanos , Lactente , Fórmulas Infantis/química , Metanálise como Assunto , Leite Humano/química , Mães , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Immunity ; 44(3): 582-596, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26921108

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a devastating lung disorder with increasing incidence. Mitochondrial oxidative stress in alveolar macrophages is directly linked to pulmonary fibrosis. Mitophagy, the selective engulfment of dysfunctional mitochondria by autophagasomes, is important for cellular homeostasis and can be induced by mitochondrial oxidative stress. Here, we show Akt1 induced macrophage mitochondrial reactive oxygen species (ROS) and mitophagy. Mice harboring a conditional deletion of Akt1 in macrophages (Akt1(-/-)Lyz2-cre) and Park2(-/-) mice had impaired mitophagy and reduced active transforming growth factor-ß1 (TGF-ß1). Although Akt1 increased TGF-ß1 expression, mitophagy inhibition in Akt1-overexpressing macrophages abrogated TGF-ß1 expression and fibroblast differentiation. Importantly, conditional Akt1(-/-)Lyz2-cre mice and Park2(-/-) mice had increased macrophage apoptosis and were protected from pulmonary fibrosis. Moreover, IPF alveolar macrophages had evidence of increased mitophagy and displayed apoptosis resistance. These observations suggest that Akt1-mediated mitophagy contributes to alveolar macrophage apoptosis resistance and is required for pulmonary fibrosis development.


Assuntos
Fibrose Pulmonar Idiopática/imunologia , Pulmão/patologia , Macrófagos Alveolares/fisiologia , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/genética , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Fibrose , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Mitofagia/genética , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/genética , Espécies Reativas de Oxigênio/metabolismo , Deleção de Sequência/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
20.
Am J Respir Cell Mol Biol ; 55(1): 58-71, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26699812

RESUMO

M2 macrophages are implicated in the development of pulmonary fibrosis as they generate profibrotic signals. The polarization process, at least in part, is regulated by epigenetic modulation. Because Cu,Zn-superoxide dismutase-induced H2O2 can polarize macrophages to a profibrotic M2 phenotype, we hypothesized that modulation of the redox state of the cell is involved in the epigenetic modulation of the macrophage phenotype. In this study, we show that signal transducer and activator of transcription 6 (STAT6) regulates Jumonji domain containing (Jmjd) 3, a histone H3 lysine 27 demethylase, and mutation of a redox-sensitive cysteine in STAT6 attenuates jmjd3 expression. Moreover, Jmjd3 deficiency abrogates profibrotic M2 gene expression. Treatment with leflunomide, which reduces mitochondrial reactive oxygen species production and tyrosine phosphorylation, inhibits jmjd3 expression and M2 polarization, as well as development of a fibrotic phenotype. Taken together, these observations provide evidence that the redox regulation of Jmjd3 is a unique regulatory mechanism for Cu,Zn-superoxide dismutase-mediated profibrotic M2 polarization. Furthermore, leflunomide, which reduces reactive oxygen species production and tyrosine phosphorylation, may prove to be therapeutic in the treatment of asbestos-induced pulmonary fibrosis.


Assuntos
Polaridade Celular , Histona Desmetilases com o Domínio Jumonji/metabolismo , Macrófagos/patologia , Superóxido Dismutase-1/metabolismo , Animais , Linhagem Celular , Polaridade Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-4/metabolismo , Isoxazóis/farmacologia , Histona Desmetilases com o Domínio Jumonji/genética , Leflunomida , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/genética , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Modelos Biológicos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Fibrose Pulmonar/prevenção & controle , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT6/deficiência , Fator de Transcrição STAT6/metabolismo
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