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1.
Biotechnol Bioeng ; 120(4): 1000-1014, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36575047

RESUMO

The environmental consequences of plastic waste have impacted all kingdoms of life in terrestrial and aquatic ecosystems. However, as the burden of plastic pollution has increased, microbes have evolved to utilize anthropogenic polymers as nutrient sources. Of depolymerase enzymes, the best characterized is PETase, which hydrolyzes aromatic polyesters. PETase engineering has made impressive progress in recent years; however, further optimization of engineered PETase toward industrial application has been limited by lower throughput techniques used in protein purification and activity detection. Here, we address these deficiencies through development of a higher-throughput PETase engineering platform. Secretory expression via YebF tagging eliminates lysis and purification steps, facilitating production of large mutant libraries. Fluorescent detection of degradation products permits rapid screening of depolymerase activity in microplates as opposed to serial chromatographic methods. This approach enabled development of more stable PETase, semi-rational (SR) PETase variant containing previously unpublished mutations. SR-PETase releases 1.9-fold more degradation products and has up to 7.4-fold higher activity than wild-type PETase over 10 days at 40°C. These methods can be adapted to a variety of chemical environments, enabling screening of PETase mutants in applications-relevant conditions. Overall, this work promises to facilitate advancements in PETase engineering toward industrial depolymerization of plastic waste.


Assuntos
Ecossistema , Polietilenotereftalatos , Polietilenotereftalatos/metabolismo , Plásticos/metabolismo
2.
Ophthalmic Plast Reconstr Surg ; 38(6): e173-e176, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35604381

RESUMO

The purpose of this report is to discuss high-pressure injection injuries involving the face and orbit and discuss factors affecting prognosis and management as these injuries are rare and uniquely challenging to manage given the complex anatomy and extensive damage that may occur. In this case, we present severe injury to the left orbit, maxillofacial region, and neck of a 29-year-old male who suffered a high-pressure diesel injection injury requiring several surgical debridements, intensive care unit (ICU) level care, and ultimately sub-total exenteration. Initial management involved systemic antibiotics, steroids, and surgical debridement; however, our patient experienced subsequent rapid deterioration resulting in admission for more aggressive subspecialty intervention. Decision-making was guided by serial CT of the face and orbits, and C-reactive protein (CRP) levels in addition to the physical examination. His course was complicated by progressive extensive soft tissue necrosis requiring 8 surgical debridements and optic nerve tenting despite orbital decompression resulting in loss of the OS. Ultimately, definitive treatment required sub-total exenteration and negative wound pressure therapy over the orbit followed by eyelid reconstruction as an outpatient. We conclude that without prompt recognition and meticulous debridement, the resultant injury from high-pressure injection injuries can be devastating and lead to permanent vision loss, loss of an eye, loss of facial function, and airway compromise depending on the location of the injury. A multi-disciplinary team involving oculoplastics, otolaryngology, infectious disease, and ICU should be assembled based on the complexity of this injury and its sequela. CRP can be useful to monitor patient recovery and the need for further surgical intervention. When debridement results in complex wounds over the orbit and face, negative pressure wound therapy should be considered.


Assuntos
Pálpebras , Órbita , Masculino , Humanos , Adulto , Órbita/cirurgia , Órbita/lesões , Injeções , Nervo Óptico , Cuidados Críticos
3.
Compr Rev Food Sci Food Saf ; 21(6): 5004-5037, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36201393

RESUMO

Trehalose is a nonreducing disaccharide composed of two glucose molecules linked by α, α-1,1-glycosidic bond. It is present in a wide variety of organisms, including bacteria, fungi, insects, plants, and invertebrate animals. Trehalose has distinct physical and chemical properties that have been investigated for their biological importance in a range of prokaryotic and eukaryotic species. Emerging research on trehalose has identified untapped opportunities for its application in the food, medical, pharmaceutical, and cosmetics industries. This review summarizes the chemical and biological properties of trehalose, its occurrence and metabolism in living organisms, its protective role in molecule stabilization, and natural and commercial production methods. Utilization of trehalose in the food industry, in particular how it stabilizes protein, fat, carbohydrate, and volatile compounds, is also discussed in depth. Challenges and opportunities of its application in specific applications (e.g., diagnostics, bioprocessing, ingredient technology) are described. We conclude with a discussion on the potential of leveraging the unique molecular properties of trehalose in molecular stabilization for improving the safety, quality, and sustainability of our food systems.


Assuntos
Fungos , Trealose , Animais , Trealose/química , Trealose/metabolismo , Fungos/metabolismo , Bactérias/metabolismo , Plantas/metabolismo , Indústria Alimentícia
4.
Cancer ; 127(4): 535-543, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33119176

RESUMO

BACKGROUND: Persistent controversy exists with regard to how and when patients with head and neck cancer should undergo imaging after definitive therapy. The current study was conducted to evaluate whether the type of imaging modality used in posttreatment imaging impacts cancer-specific survival for patients with advanced head and neck squamous cell carcinoma. METHODS: A retrospective study of National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) program-Medicare-linked data in patients with an advanced stage of the 3 most common head and neck malignancies (oral cavity, oropharynx, and larynx) was conducted. Hazard ratios and 95% CIs for cancer-specific survival were estimated for patients diagnosed with any of these cancers between 2006 and 2015. RESULTS: Significant improvement with regard to cancer-specific survival was observed among patients with American Joint Committee on Cancer stage III and stage IVA laryngeal cancer who underwent positron emission tomography (PET) and/or computed tomography (CT) imaging during the first 6 months after receipt of definitive treatment (hazard ratio, 0.517; 95% CI, 0.33-0.811) compared with those who underwent CT. There was a trend toward an improvement in cancer-specific survival among patients with oral cavity or oropharyngeal malignancies who underwent PET/CT imaging, but it did not reach statistical significance. CONCLUSIONS: Compared with CT imaging, posttreatment imaging with PET was associated with improved survival in patients with advanced laryngeal carcinoma.


Assuntos
Laringe/diagnóstico por imagem , Boca/diagnóstico por imagem , Orofaringe/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Idoso , Intervalo Livre de Doença , Fluordesoxiglucose F18 , Humanos , Neoplasias Laríngeas , Laringe/patologia , Masculino , Medicare/economia , Pessoa de Meia-Idade , Boca/patologia , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Orofaringe/patologia , Tomografia por Emissão de Pósitrons , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Estados Unidos
5.
Bioconjug Chem ; 32(3): 466-481, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33661607

RESUMO

Bacteriophages are viruses whose ubiquity in nature and remarkable specificity to their host bacteria enable an impressive and growing field of tunable biotechnologies in agriculture and public health. Bacteriophage capsids, which house and protect their nucleic acids, have been modified with a range of functionalities (e.g., fluorophores, nanoparticles, antigens, drugs) to suit their final application. Functional groups naturally present on bacteriophage capsids can be used for electrostatic adsorption or bioconjugation, but their impermanence and poor specificity can lead to inconsistencies in coverage and function. To overcome these limitations, researchers have explored both genetic and chemical modifications to enable strong, specific bonds between phage capsids and their target conjugates. Genetic modification methods involve introducing genes for alternative amino acids, peptides, or protein sequences into either the bacteriophage genomes or capsid genes on host plasmids to facilitate recombinant phage generation. Chemical modification methods rely on reacting functional groups present on the capsid with activated conjugates under the appropriate solution pH and salt conditions. This review surveys the current state-of-the-art in both genetic and chemical bacteriophage capsid modification methodologies, identifies major strengths and weaknesses of methods, and discusses areas of research needed to propel bacteriophage technology in development of biosensors, vaccines, therapeutics, and nanocarriers.


Assuntos
Bacteriófagos/química , Bacteriófagos/genética , Proteínas do Capsídeo/química , Aminoácidos/química , Peptídeos/química
6.
J Natl Compr Canc Netw ; 19(1): 57-67, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32987364

RESUMO

BACKGROUND: In this population study, we compared head and neck cancer (HNC) prognosis and risk factors in 2 underserved minority groups (Hispanic and Black non-Hispanic patients) with those in other racial/ethnicity groups. METHODS: In this SEER-Medicare database study in patients with HNC diagnosed in 2006 through 2015, we evaluated cancer-specific survival (CSS) between different racial/ethnic cohorts as the main outcome. Patient demographics, tumor factors, socioeconomic status, and treatments were analyzed in relation to the primary outcomes between racial/ethnic groups. RESULTS: Black non-Hispanic patients had significantly worse CSS than all other racial/ethnic groups, including Hispanic patients, in unadjusted univariate analysis (Black non-Hispanic patients: hazard ratio, 1.48; 95% CI, 1.33-1.65; Hispanic patients: hazard ratio, 1.12; 95% CI, 0.99-1.28). To investigate the association of several variables with CSS, data were stratified for multivariate analysis using forward Cox regression. This identified socioeconomic status, cancer stage, and receipt of treatment as predictive factors for the survival differences. Black non-Hispanic patients were most likely to present at a later stage (odds ratio, 1.62; 95% CI, 1.38-1.90) and to receive less treatment (odds ratio, 0.67; 95% CI, 0.55-0.81). Unmarried status, high poverty areas, increased emergency department visits, and receipt of healthcare at non-NCI/nonteaching hospitals also significantly impacted stage and treatment. CONCLUSIONS: Black non-Hispanic patients have a worse HNC prognosis than patients in all other racial/ethnic groups, including Hispanic patients. Modifiable risk factors include access to nonemergent care and prevention measures, such as tobacco cessation; presence of social support; communication barriers; and access to tertiary centers for appropriate treatment of their cancers.


Assuntos
Neoplasias de Cabeça e Pescoço , Medicare , Idoso , Células Epiteliais , Etnicidade , Neoplasias de Cabeça e Pescoço/terapia , Disparidades em Assistência à Saúde , Hispânico ou Latino , Humanos , Estudos Retrospectivos , Estados Unidos/epidemiologia
7.
Biofouling ; 35(7): 785-795, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31550928

RESUMO

Food wasted due to food spoilage remains a global challenge to the environmental sustainability and security of food supply. In food manufacturing, post-processing contamination of food can occur due to persistent bacterial biofilms, which can be resistant to conventional cleaning and sanitization. The objective was to characterize the efficacy of a polymeric coating in reducing Pseudomonas aeruginosa biofilm establishment and facilitating its removal. Viable cell density of a 48 h biofilm was reduced by 2.10 log cfu cm-2 on the coated surface, compared to native polypropylene. Confocal laser scanning and electron microscopy indicated reductions in mature biofilm viability and thickness on the coated material. The antifouling coating improved cleanability, with ∼2.5 log cfu cm-2 of viable cells remaining after 105 min cleaning by water at 65 °C, compared to 4.5 log cfu cm-2 remaining on native polypropylene. Such coatings may reduce the persistence of biofilms in food processing environments, in support of reducing food spoilage and waste.


Assuntos
Biofilmes , Pseudomonas aeruginosa/fisiologia , Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos
8.
Chem Soc Rev ; 46(5): 1272-1283, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-27942636

RESUMO

Pathogenic bacterial contamination is a major threat to human health and safety. In this review, we summarize recent strategies for the integration of recognition elements with nanomaterials for the detection and sensing of pathogenic bacteria. Nanoprobes can provide sensitive and specific detection of bacterial cells, which can be applied across multiple applications and industries.


Assuntos
Bactérias/isolamento & purificação , Técnicas Biossensoriais , Nanoestruturas/química , Humanos
9.
Cancer ; 123(16): 3040-3049, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28369832

RESUMO

BACKGROUND: Sinonasal malignancies are a rare and heterogeneous group of tumors for which there is a paucity of robust data with which to guide management decisions. The authors used the National Cancer Data Base to better understand the presenting characteristics of these tumors and to compare outcomes by treatment modality. METHODS: The National Cancer Data Base was queried for sinonasal malignancies diagnosed between 2004 and 2012. Overall survival was assessed using multivariate analyses and propensity score matching. RESULTS: A total of 11,160 patients were identified for the initial analysis. The majority were male, aged 40 to 69 years, with tumors of the nasal cavity or maxillary sinus. Squamous cell histology was most common. The majority of patients presented with advanced tumor stage but without locoregional lymph node or distant metastases. Treatment modalities were compared for squamous cell carcinomas. In multivariate analysis, compared with surgery alone, patients who received adjuvant radiotherapy (hazard ratio [HR], 0.658 [P<.001]), adjuvant chemoradiotherapy (HR, 0.696 [P = .002]), or neoadjuvant therapy (HR, 0.656 [P = .007]) had improved overall survival. Patients who received radiotherapy alone (HR, 1.294 [P = .001]) or chemotherapy alone (HR, 1.834 [P<.001]) had worse outcomes. These findings were validated in propensity score matching. It is important to note that neoadjuvant chemoradiotherapy was associated with achieving a negative surgical margin (odds ratio, 2.641 [P = .045]). CONCLUSIONS: Surgery is the mainstay of therapy for patients with sinonasal malignancies, but multimodality therapy is associated with improved overall survival. Cancer 2017;123:3040-49. © 2017 American Cancer Society.


Assuntos
Carcinoma Adenoide Cístico/terapia , Carcinoma Adenoescamoso/terapia , Carcinoma Mucoepidermoide/terapia , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Melanoma/terapia , Neoplasias Nasais/terapia , Neoplasias dos Seios Paranasais/terapia , Adolescente , Adulto , Idoso , Carcinoma Adenoide Cístico/patologia , Carcinoma Adenoescamoso/patologia , Carcinoma Mucoepidermoide/patologia , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Lactente , Recém-Nascido , Linfonodos/patologia , Masculino , Margens de Excisão , Melanoma/patologia , Pessoa de Meia-Idade , Análise Multivariada , Terapia Neoadjuvante , Neoplasias Nasais/patologia , Procedimentos Cirúrgicos Otorrinolaringológicos , Neoplasias dos Seios Paranasais/patologia , Prognóstico , Pontuação de Propensão , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Taxa de Sobrevida , Adulto Jovem
10.
Cancer ; 123(4): 600-608, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27727461

RESUMO

BACKGROUND: Although laryngectomy is the treatment of choice for patients with T4 larynx cancer, many patients are unable or unwilling to undergo laryngectomy and instead pursue larynx-preservation strategies combining radiotherapy (RT) and chemotherapy. Herein, the authors analyzed the National Cancer Data Base to evaluate overall survival (OS) between patients treated with surgical and organ-preserving modalities. METHODS: The National Cancer Data Base was queried for patients diagnosed from 2004 through 2012 with T4M0 laryngeal cancer who underwent either laryngectomy (surgery) with adjuvant RT (SRT), chemotherapy starting concurrently within 7 days of RT (CCRT), or multiagent induction chemotherapy starting 43 to 98 days before RT (ICRT). Multivariate analysis and propensity score matching were used to explore the association between the intervention and OS. Recursive partitioning analysis was performed to identify groups benefiting from particular modalities. RESULTS: A total of 1559 patients who underwent SRT, 1597 patients who underwent CCRT, and 386 patients who underwent ICRT were included. Adjusting for covariates, CCRT was found to be associated with inferior OS compared with SRT (hazard ratio [HR], 1.55; 95% confidence interval [95% CI], 1.41-1.70 [P<.01]) and with ICRT (HR, 1.25; 95% CI, 1.07-1.45 [P<.01]). OS among the patients treated with SRT did not appear to differ significantly from that of the ICRT cohort (HR, 0.87; 95% CI, 0.73-1.03 [P = 0.10]), a finding confirmed with propensity score matching. Recursive partitioning analysis identified no subset of patients that derived an OS benefit from either approach over the other. CONCLUSIONS: OS among patients undergoing SRT was found to be superior to that of patients treated with CCRT but did not significantly differ from that of those undergoing ICRT. Because these intriguing findings require validation, SRT should remain the standard of care for patients with this disease. However, organ preservation with ICRT may be a reasonable alternative in certain patients. Cancer 2017;123:600-608. © 2016 American Cancer Society.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirurgia , Adulto , Idoso , Cisplatino/uso terapêutico , Terapia Combinada/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Laríngeas/epidemiologia , Laringectomia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia Adjuvante/efeitos adversos
11.
Nanotechnology ; 28(6): 06LT01, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28044995

RESUMO

In this study, we successfully applied vapor-phase polymerization towards the synthesis of PEDOT nanofibers which were subsequently functionalized with gold particles and used as electrodes for electrochemical sensing. Two methods were used to synthesize the PEDOT nanofibers including (1) electrospinning followed by vapor-phase polymerization (EVP), and (2) one-step vapor-phase polymerization (OSVP). The average diameter of EVP fibers was approximately 350 nm, and OSVP was approximately 200 nm. Gold particles (∼500 nm) were synthesized by an oxidation-reduction reaction between gold precursors and residue EDOT monomers on the surface of the PEDOT nanofibers. In order to investigate the electrochemical performance of these electrodes, ascorbic acid was chosen as an analyte model. Our results indicated that PEDOT nanofiber electrodes showed an enhanced response with respect to bare gold electrodes. Furthermore, the OSVP PEDOT nanofibers with gold particles demonstrated the highest sensitivity at low ascorbic acid concentrations. These hierarchically assembled, gold particle-decorated, conductive polymer nanofibers were further fabricated into flexible electrodes, demonstrating a potential in advanced applications such as wearable electronics.

12.
Biofouling ; 32(5): 523-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27020838

RESUMO

Biofilm control remains a challenge to food safety. A well-studied non-fouling coating involves codeposition of polytetrafluoroethylene (PTFE) during electroless plating. This coating has been reported to reduce foulant build-up during pasteurization, but opportunities remain in demonstrating its efficacy in inhibiting biofilm formation. Herein, the initial adhesion, biofilm formation, and removal kinetics of Bacillus cereus on Ni-PTFE-modified stainless steel (SS) are characterized. Coatings lowered the surface energy of SS and reduced biofilm formation by > 2 log CFU cm(-2). Characterization of the kinetics of biofilm removal during cleaning demonstrated improved cleanability on the Ni-PTFE coated steel. There was no evidence of biofilm after cleaning by either solution on the Ni-PTFE coated steel, whereas more than 3 log and 1 log CFU cm(-2) of bacteria remained on the native steel after cleaning with water and an alkaline cleaner, respectively. This work demonstrates the potential application of Ni-PTFE non-fouling coatings on SS to improve food safety by reducing biofilm formation and improving the cleaning efficiency of food processing equipment.


Assuntos
Bacillus cereus/fisiologia , Aderência Bacteriana , Biofilmes , Carga Bacteriana , Detergentes/farmacologia , Cinética , Politetrafluoretileno , Aço Inoxidável
13.
J Dairy Sci ; 99(12): 9502-9513, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27692715

RESUMO

The development of bacterial biofilms on stainless steel (SS) surfaces poses a great threat to the quality of milk and other dairy products as the biofilm-embedded bacteria can survive thermal processing. Established biofilms offer cleaning challenges because they are resistant to most of the regular cleaning protocols. Sporeforming thermoduric organisms entrapped within biofilm matrix can also form heat-resistant spores, and may result in a long-term persistent contamination. The main objective of this study was to evaluate the efficacy of different nonfouling coatings [AMC 18 (Advanced Materials Components Express, Lemont, PA), Dursan (SilcoTek Corporation, Bellefonte, PA), Ni-P-polytetrafluoroethylene (PTFE, Avtec Finishing Systems, New Hope, MN), and Lectrofluor 641 (General Magnaplate Corporation, Linden, NJ)] on SS plate heat exchanger surfaces, to resist the formation of bacterial biofilms. It was hypothesized that modified SS surfaces would promote a lesser amount of deposit buildup and bacterial adhesion as compared with the native SS surface. Vegetative cells of aerobic sporeformers, Geobacillus stearothermophilus (ATCC 15952), Bacillus licheniformis (ATCC 6634), and Bacillus sporothermodurans (DSM 10599), were used to study biofilm development on the modified and native SS surfaces. The adherence of these organisms, though influenced by surface energy and hydrophobicity, exhibited no apparent relation with surface roughness. The Ni-P-PTFE coating exhibited the least bacterial attachment and milk solid deposition, and hence, was the most resistant to biofilm formation. Scanning electron microscopy, which was used to visualize the extent of biofilm formation on modified and native SS surfaces, also revealed lower bacterial attachment on the Ni-P-PTFE as compared with the native SS surface. This study thus provides evidence of reduced biofilm formation on the modified SS surfaces.


Assuntos
Biofilmes , Aço Inoxidável , Animais , Aderência Bacteriana , Leite , Politetrafluoretileno
14.
J Dairy Sci ; 98(9): 5983-94, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26142857

RESUMO

Application of nonfouling coatings on thermal processing equipment can improve operational efficiency. However, to enable effective commercial translation, a need exists for more comprehensive studies on the stability of nonfouling coatings after exposure to different sanitizers. In the current study, the influence of different commercial dairy equipment sanitizers on the nonfouling properties of stainless steel modified with electroless Ni-polytetrafluoroethylene (PTFE) coatings was determined. Surface properties, such as dynamic contact angle, surface energy, surface morphology, and elemental composition, were measured before and after the coupons were exposed to the sanitizers for 168 cleaning cycles. The fouling behavior of Ni-PTFE-modified stainless steel coupons after exposure was also evaluated by processing raw milk on a self-fabricated benchtop-scale plate heat exchanger. The results indicated that peroxide sanitizer had only minor effect on the Ni-PTFE-modified stainless steel surface, whereas chlorine- and iodine-based sanitizers influenced the surface properties drastically. The coupons after 168 cycles of exposure to peroxide sanitizer accumulated the least amount of fouling material (4.44±0.24mg/cm(2)) compared with the coupons exposed to the other 3 sanitizers. These observations indicated that the Ni-PTFE nonfouling coating retained antifouling properties after 168 cycles of exposure to peroxide-based sanitizer, supporting their potential application as nonfouling coatings for stainless steel dairy processing equipment.


Assuntos
Materiais Revestidos Biocompatíveis/química , Níquel/química , Politetrafluoretileno/química , Cloro/química , Desinfetantes/química , Tecnologia de Alimentos , Iodo/química , Saneamento , Aço Inoxidável/química
15.
J Nurs Adm ; 45(9): 443-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26247321

RESUMO

Healthcare leaders face a multitude of priorities demanding their attention and resources, from patient, employee safety and hospital-acquired conditions to predicting future revenue in the context of healthcare reform. Assessing value requires balancing outcomes and experience with cost. How does allocating funds for professional nursing conferences measure up? What is a valid return on investment when we send staff nurses to professional conferences, specifically the annual Magnet® conference? The following article describes how Cincinnati Children's Hospital Medical Center answered these questions and redefined the expectations for conference attendees while enhancing the experience and the reportable outcomes for practice and the organization.


Assuntos
Congressos como Assunto/organização & administração , Modelos Organizacionais , Recursos Humanos de Enfermagem Hospitalar/educação , Adulto , Análise Custo-Benefício , Feminino , Hospitais Pediátricos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Educacionais , Ohio , Poder Psicológico
16.
Biomacromolecules ; 15(11): 3915-22, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25252004

RESUMO

Nanostructure-enabled hierarchical assembly holds promise for efficient biocatalyst immobilization for improved stability in bioprocessing. In this work we demonstrate the use of a hierarchical assembly immobilization strategy to enhance the physicochemical properties and stability of lipase B from Candida antarctica (CaLB). CaLB was complexed with iron oxide nanoparticles followed by interfacial assembly at the surface of an oil-in-water emulsion. Subsequent ring opening polymerization of the oil provided cross-linked microparticles that displayed an increase in catalytic efficiency when compared to the native enzyme and Novozym 435. The hierarchical immobilized enzyme assembly showed no leakage from the support in 50% acetonitrile and could be magnetically recovered across five cycles. Immobilized lipase exhibited enhanced thermal and pH stability, providing 72% activity retention after 24 h at 50 °C (pH 7.0) and 62% activity retention after 24 h at pH 3.0 (30 °C); conditions resulting in complete deactivation of the native lipase.


Assuntos
Enzimas Imobilizadas/química , Compostos Férricos/química , Proteínas Fúngicas/química , Lipase/química , Nanopartículas Metálicas/química , Estabilidade Enzimática/fisiologia , Enzimas Imobilizadas/metabolismo , Compostos Férricos/metabolismo , Proteínas Fúngicas/metabolismo , Lipase/metabolismo
17.
J Dairy Sci ; 97(1): 166-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24239074

RESUMO

Active packaging, in which active agents are embedded into or on the surface of food packaging materials, can enhance the nutritive value, economics, and stability of food, as well as enable in-package processing. In one embodiment of active food packaging, lactase was covalently immobilized onto packaging films for in-package lactose hydrolysis. In prior work, lactase was covalently bound to low-density polyethylene using polyethyleneimine and glutaraldehyde cross-linkers to form the packaging film. Because of the potential contaminants of proteases, lipases, and spoilage organisms in typical enzyme preparations, the goal of the current work was to determine the effect of immobilized-lactase active packaging technology on unanticipated side effects, such as shortened shelf-life and reduced product quality. Results suggested no evidence of lipase or protease activity on the active packaging films, indicating that such active packaging films could enable in-package lactose hydrolysis without adversely affecting product quality in terms of dairy protein or lipid stability. Storage stability studies indicated that lactase did not migrate from the film over a 49-d period, and that dry storage resulted in 13.41% retained activity, whereas wet storage conditions enabled retention of 62.52% activity. Results of a standard plate count indicated that the film modification reagents introduced minor microbial contamination; however, the microbial population remained under the 20,000 cfu/mL limit through the manufacturer's suggested 14-d storage period for all film samples. This suggests that commercially produced immobilized lactase active packaging should use purified cross-linkers and enzymes. Characterization of unanticipated effects of active packaging on food quality reported here is important in demonstrating the commercial potential of such technologies.


Assuntos
Embalagem de Alimentos/métodos , Qualidade dos Alimentos , Leite/química , Leite/microbiologia , Animais , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Lactase/metabolismo , Polietileno/metabolismo
18.
J Sci Food Agric ; 94(8): 1681-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24227447

RESUMO

BACKGROUND: Although surface characteristics of food contact materials are known to alter the efficacy of cleaning procedures there is a lack of data establishing how cleaning/sanitization practices affect the surface characteristics of materials used for produce handling on-farm. The overall objective of this work was to characterize the effects of cleaning and sanitization procedures on the surface properties of new and extended-wear polyethylene bins used for produce harvest and handling. RESULTS: Compared to detergent cleaned samples, chlorine and quaternary ammonium sanitization resulted in a decrease in advancing contact angle from 100° to 88° and 59°, respectively, after 2 min exposure. However, changes in surface chemistry were not observed. Increasing sanitization time to 144 min (representative of 4320 sanitization cycles) resulted in an increase in contact angle to 73° for quaternary ammonium sanitization and a decrease in contact angle to 75° for chlorine sanitization. Abrasion increased contact angle hysteresis due to enhanced surface roughness. The hysteresis effect of abraded material was reduced with quaternary ammonium treatment. CONCLUSIONS: This work indicates that sanitizing agents employed in on-farm cleaning can alter the surface characteristics of polyethylene picking bins and should be considered in developing cleaning and sanitization procedures.


Assuntos
Detergentes/efeitos adversos , Embalagem de Alimentos/instrumentação , Polietileno , Agricultura , Cloro , Compostos de Amônio Quaternário , Saneamento , Propriedades de Superfície
19.
Materials (Basel) ; 16(12)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37374629

RESUMO

Food borne illness remains a major threat to public health despite new governmental guidelines and industry standards. Cross-contamination of both pathogenic and spoilage bacteria from the manufacturing environment can promote consumer illness and food spoilage. While there is guidance in cleaning and sanitation procedures, manufacturing facilities can develop bacterial harborage sites in hard-to-reach areas. New technologies to eliminate these harborage sites include chemically modified coatings that can improve surface characteristics or incorporate embedded antibacterial compounds. In this article we synthesize a 16 carbon length quaternary ammonium bromide (C16QAB) modified polyurethane and perfluoropolyether (PFPE) copolymer coating with low surface energy and bactericidal properties. The introduction of PFPE to the polyurethane coatings lowered the critical surface tension from 18.07 mN m-1 in unmodified polyurethane to 13.14 mN m-1 in modified polyurethane. C16QAB + PFPE polyurethane was bactericidal against Listeria monocytogenes (>6 log reduction) and Salmonella enterica (>3 log reduction) after just eight hours of contact. The combination of low surface tension from the perfluoropolyether and antimicrobial from the quaternary ammonium bromide produced a multifunctional polyurethane coating suitable for coating on non-food contact food production surfaces to prevent survival and persistence of pathogenic and spoilage organisms.

20.
ACS Appl Mater Interfaces ; 15(24): 29511-29524, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37294186

RESUMO

The environmental and economic burden of food waste demands new preservation technologies to reduce the degradative actions of spoilage such as moisture, oxygen, and microorganisms. Direct food additives can help maintain product quality; however, the limited life span of these additives combined with consumer desire for "clean label" products has motivated research into new food manufacturing technologies like active and intelligent packaging that can prevent and detect food spoilage. In this work, curcumin was grafted to polypropylene (PP-g-Cur) via reactive extrusion to produce nonmigratory active and intelligent packaging through a solvent-free, efficient, and continuous method. Immobilization of curcumin was confirmed by a standard migration assay exhibiting a maximum of 0.011 mg/cm2 migration, significantly below the EU migratory limit for food contact materials (0.1 mg/cm2). Compared to native PP films, PP-g-Cur films blocked 93% of UV light while retaining 64% transparency in the visible region, allowing for desirable product visibility while inhibiting UV degradation of packaged goods. While the ability of PP-g-Cur to inhibit growth of E. coli and L. monocytogenes was insignificant compared to control PP, free curcumin exhibited poor bacterial inhibition as well, suggesting that without hydrophilic modification, native curcumin has limited antimicrobial efficacy. PP-g-Cur films displayed significant radical scavenging in both organic (11.71 ± 3.02 TroloxEq (nmol/cm2)) and aqueous (3.18 ± 1.04 TroloxEq (nmol/cm2)) matrices, exhibiting potential for antioxidant behavior in both lipophilic and hydrophilic applications. Finally, when PP-g-Cur films were exposed to ammonia, an indicator of microbial growth, the color visually and quantitatively changed from yellow to red, demonstrating potential to indicate spoilage. These findings demonstrate the potential of a scalable technology to produce active and intelligent packaging to limit food waste and advance the capabilities of functional materials in a variety of applications.


Assuntos
Curcumina , Eliminação de Resíduos , Humanos , Escherichia coli , Alimentos , Embalagem de Alimentos/métodos , Polipropilenos/química
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