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1.
J Clin Monit Comput ; 38(1): 229-234, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37460867

RESUMO

Multimodal intraoperative neurophysiological monitoring (IONM) is highly valuable in scoliosis surgeries for monitoring spinal cord function, particularly during instrumentation. Accurate timing of baseline recordings of TcMEP and SSEP is crucial, as any changes observed during surgery and instrumentation are compared to these baseline recordings. However, the impact of ultrasound-guided erector spinae block (USG-ESPB) on SSEP and TcMEP is not well-studied in scoliosis surgery. In this report, we present two cases of scoliosis surgery where bilateral two-level USG-ESPB using different concentrations of ropivacaine (0.375% and 0.2%) resulted in a transient and significant deterioration of TcMEP, occurring 3 minutes after the block and lasting for 20 minutes. Remarkably, SSEPs remained unchanged during this period. These findings suggest that USG-ESPB may produce TcMEP changes, highlighting the importance of carefully considering the timing of baseline TcMEP acquisition in scoliosis surgery.


Assuntos
Monitorização Neurofisiológica Intraoperatória , Escoliose , Ferida Cirúrgica , Humanos , Potencial Evocado Motor/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Escoliose/cirurgia , Monitorização Neurofisiológica Intraoperatória/métodos , Procedimentos Neurocirúrgicos/métodos , Ferida Cirúrgica/cirurgia
2.
Sensors (Basel) ; 23(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36679400

RESUMO

Biofouling is the major factor that limits long-term monitoring studies with automated optical instruments. Protection of the sensing areas, surfaces, and structural housing of the sensors must be considered to deliver reliable data without the need for cleaning or maintenance. In this work, we present the design and field validation of different techniques for biofouling protection based on different housing materials, biocides, and transparent coatings. Six optical turbidity probes were built using polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), PLA with copper filament, ABS coated with PDMS, ABS coated with epoxy and ABS assembled with a system for in situ chlorine production. The probes were deployed in the sea for 48 days and their anti-biofouling efficiency was evaluated using the results of the field experiment, visual inspections, and calibration signal loss after the tests. The PLA and ABS were used as samplers without fouling protection. The probe with chlorine production outperformed the other techniques, providing reliable data during the in situ experiment. The copper probe had lower performance but still retarded the biological growth. The techniques based on transparent coatings, epoxy, and PDMS did not prevent biofilm formation and suffered mostly from micro-biofouling.


Assuntos
Incrustação Biológica , Desinfetantes , Biofilmes , Cloro , Cobre/química , Incrustação Biológica/prevenção & controle , Cloretos
3.
J Clin Monit Comput ; 37(6): 1627-1633, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37351761

RESUMO

Intra-operative monitoring has been a crucial tool in modern neurosurgery as it allows to optimize surgical outcome whilst reducing neurological deficits. Somatosensory evoked potentials are routinely monitored in most spinal and brain surgeries due to providing invaluable information regarding the functional integrity of sensory pathways. The use of this neurophysiological technique is particular useful when positioning patients in semi-sitting position during posterior fossa surgery. However, there is general agreement within the intra-operative neuromonitoring community that either upper or lower limb SSEPs monitoring typically suffice. Nonetheless, we report a case study of a patient in whom lower limb SSEPs were independently affected from upper limb SSEPs during positioning. In this respect, we suggest that both upper and lower limb SSEPs monitoring should be considered during semi-sitting positioning in patients undergoing posterior fossa surgery.


Assuntos
Potenciais Somatossensoriais Evocados , Postura Sentada , Humanos , Potenciais Somatossensoriais Evocados/fisiologia , Coluna Vertebral/cirurgia , Monitorização Intraoperatória/métodos , Procedimentos Neurocirúrgicos/métodos
4.
Plant Foods Hum Nutr ; 78(3): 526-532, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37466823

RESUMO

Ilex paraguariensis is a native tree from South America known for the presence of bioactive compounds, and its processed leaves are consumed as hot and cold infusions. After harvest (step 1), the leaves are subjected to flame blanching to inactive the enzymes (step 2), followed by drying and milling (step 3). The impacts of I. paraguariensis processing on leaf composition were investigated by extracting the major compounds (chlorogenic and isochlorogenic acids (3-CQA, 4-CQA, 5-CQA, 3,4-DQA, 3,5-DQA and 4,5-DQA), p-coumaric acid, caffeine and rutin) using different ratios of ethanol and water as extraction solvent (EW 25:75, 50:50, and 75:25 (w/w)). The solvent ratio of EW 50:50 was more effective in extracting the chlorogenic acids isomers, with retention of chlorogenic acids of 3463, 9485, and 9516 µg mL- 1 for steps 1, 2, and 3, respectively. Rutin and p-coumaric acid exhibited similar behavior with the increment of processing steps; however, p-coumaric acid was only detected in steps 2 and 3 for the solvent ratios EW 50:50 and 25:50. The caffeine extraction from I. paraguariensis varied from 936 to 1170 µg mL- 1 for all processing steps, with emphasis on its concentration extracted in step 1. The evolution of processing steps led to a higher retention of phenolic compounds from I. paraguariensis, which was not observed when using different solvent ratios, and the solvent ratio EW 50:50 was more effective for the extraction of chlorogenic acids. The successful extraction of chlorogenic acids from I. paraguariensis in this study proved to be a promising alternative for the use of yerba mate beyond the cuia cup.


Assuntos
Ilex paraguariensis , Cafeína , Extratos Vegetais , Rutina , Solventes
5.
Crit Rev Food Sci Nutr ; : 1-13, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35866531

RESUMO

The demand for natural compounds to replace synthetic additives has aroused the interest of different sectors of society, especially the scientific community, due to their safety, biocompatibility, biodegradability and low toxicity. Alternative sources for antimicrobial compounds have been explored, such as fruit pomace. These by-products have essential compounds in their composition with different potential for application in food and packaging. In this context, this review systematizes the use of pomace from different fruits as a source of antibacterial compounds. Also, it summarizes the extraction methods and the applications of these compounds. Grape pomace, cranberry, and apple extracts are the most explored for antibacterial control, especially against genus Listeria, Salmonella, Staphylococcus, and Escherichia. In addition, phenolic acids, anthocyanins, flavonoids, and proanthocyanins are the main compounds identified in the studied fruit pomace extracts. In the reviewed articles, the biocompounds recovery is performed by methods with the absence of high temperatures (>80 °C); in some studies, the solid-liquid extraction method at mild temperatures (<30 °C) was well explored, using ethanol and water as solvent. The use of fruit processing by-products for bacterial control highlights the possibility of favoring the three pillars of sustainability (social, economic, and environmental) in the food industry.

6.
J Med Internet Res ; 23(1): e18872, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33427686

RESUMO

BACKGROUND: The low levels of control of hypertension and diabetes mellitus are a challenge that requires innovative strategies to surpass barriers of low sources, distance, and quality of health care. OBJECTIVE: The aim of this study is to develop a clinical decision support system (CDSS) for diabetes and hypertension management in primary care, to implement it in a resource-constrained region, and to evaluate its usability and health care practitioner satisfaction. METHODS: This mixed methods study is a substudy of HealthRise Brazil Project, a multinational study designed to implement pilot programs to improve screening, diagnosis, management, and control of hypertension and diabetes among underserved communities. Following the identification of gaps in usual care, a team of clinicians established the software functional requirements. Recommendations from evidence-based guidelines were reviewed and organized into a decision algorithm, which bases the CDSS reminders and suggestions. Following pretesting and expert panel assessment, pilot testing was conducted in a quasi-experimental study, which included 34 primary care units of 10 municipalities in a resource-constrained area in Brazil. A Likert-scale questionnaire evaluating perceived feasibility, usability, and utility of the application and professionals' satisfaction was applied after 6 months. In the end-line assessment, 2 focus groups with primary care physicians and nurses were performed. RESULTS: A total of 159 reminders and suggestions were created and implemented for the CDSS. At the 6-month assessment, there were 1939 patients registered in the application database and 2160 consultations were performed by primary care teams. Of the 96 health care professionals who were invited for the usability assessment, 26% (25/96) were physicians, 46% (44/96) were nurses, and 28% (27/96) were other health professionals. The questionnaire included 24 items on impressions of feasibility, usability, utility, and satisfaction, and presented global Cronbach α of .93. As for feasibility, all professionals agreed (median scores of 4 or 5) that the application could be used in primary care settings and it could be easily incorporated in work routines, but physicians claimed that the application might have caused significant delays in daily routines. As for usability, overall evaluation was good and it was claimed that the application was easy to understand and use. All professionals agreed that the application was useful (score 4 or 5) to promote prevention, assist treatment, and might improve patient care, and they were overall satisfied with the application (median scores between 4 and 5). In the end-line assessment, there were 4211 patients (94.82% [3993/4211] with hypertension and 24.41% [1028/4211] with diabetes) registered in the application's database and 7960 consultations were performed by primary health care teams. The 17 participants of the focus groups were consistent to affirm they were very satisfied with the CDSS. CONCLUSIONS: The CDSS was applicable in the context of primary health care settings in low-income regions, with good user satisfaction and potential to improve adherence to evidence-based practices.


Assuntos
Sistemas de Apoio a Decisões Clínicas/normas , Diabetes Mellitus/terapia , Hipertensão/terapia , Adulto , Brasil , Análise de Dados , Feminino , Humanos , Masculino , Projetos Piloto , Inquéritos e Questionários
7.
Sensors (Basel) ; 21(16)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34451087

RESUMO

The advanced and widespread use of microfluidic devices, which are usually fabricated in polydimethylsiloxane (PDMS), requires the integration of many sensors, always compatible with microfluidic fabrication processes. Moreover, current limitations of the existing optical and electrochemical oxygen sensors regarding long-term stability due to sensor degradation, biofouling, fabrication processes and cost have led to the development of new approaches. Thus, this manuscript reports the development, fabrication and characterization of a low-cost and highly sensitive dissolved oxygen optical sensor based on a membrane of PDMS doped with platinum octaethylporphyrin (PtOEP) film, fabricated using standard microfluidic materials and processes. The excellent mechanical and chemical properties (high permeability to oxygen, anti-biofouling characteristics) of PDMS result in membranes with superior sensitivity compared with other matrix materials. The wide use of PtOEP in sensing applications, due to its advantage of being easily synthesized using microtechnologies, its strong phosphorescence at room temperature with a quantum yield close to 50%, its excellent Strokes Shift as well as its relatively long lifetime (75 µs), provide the suitable conditions for the development of a miniaturized luminescence optical oxygen sensor allowing long-term applications. The influence of the PDMS film thickness (0.1-2.5 mm) and the PtOEP concentration (363, 545, 727 ppm) in luminescent properties are presented. This enables to achieve low detection levels in a gas media range from 0.5% up to 20%, and in liquid media from 0.5 mg/L up to 3.3 mg/L at 1 atm, 25 °C. As a result, we propose a simple and cost-effective system based on a LED membrane photodiode system to detect low oxygen concentrations for in situ applications.


Assuntos
Platina , Porfirinas , Dimetilpolisiloxanos , Oxigênio
8.
J Sci Food Agric ; 101(5): 2052-2062, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32949154

RESUMO

BACKGROUND: Red araçá is a Brazilian native species whose fruits are rich in phenolic acids, flavonoids, anthocyanins, and carotenoids. To preserve the properties of compounds during processing, red araçá pulp (RAP) was encapsulated by hydrolyzed pinhão starch (PS), tara gum (TG), and arabic gum (AG) in different blends in equal proportions, serving as a coating material. RESULTS: Fresh RAP had a gallic acid equivalent of 3098 mg per 100 g of dry weight, 156.29 µg ß-carotene per gram of dry weight, total anthocyanins of 18 mg per 100 g of dry weight and exhibited high antioxidant activity. The highest encapsulation efficiency achieved with the PS, TG, and AG blend was 80.4% for the total carotenoids, and that for the total anthocyanins was 76% with the TG and AG blend. Only one step of antioxidant activity degradation was identified, and the carrier system PSTG was efficient at maintaining the antioxidant activity, with half-life of 23.60-37.27 days. CONCLUSION: The use of PS alone as a coating material or associated with TG and AG gums resulted in improved retention of bioactive compounds, these being an excellent alternative coating material since they improved the stability of the antioxidant activity of RAP. © 2020 Society of Chemical Industry.


Assuntos
Fabaceae/química , Goma Arábica/química , Extratos Vegetais/química , Gomas Vegetais/química , Psidium/química , Amido/química , Antocianinas/química , Brasil , Carotenoides/química , Flavonoides/química , Frutas/química , Hidrólise
9.
J Sci Food Agric ; 101(1): 253-261, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33460192

RESUMO

BACKGROUND: The use of damaged beans for starch isolation comprises an end-use alternative for a product that is not accepted by the consumer. For that reason, isolation and modification of Carioca bean starch should be explored and evaluated as a suitable source for biodegradable material. The present study aimed to evaluate the synergism of physical and chemical modifications on Carioca bean starch with respect to improving the properties of biodegradable films. A heat-moisture treatment (HMT) followed by oxidation by sodium hypochlorite was performed and vice versa. RESULTS: Synergism was noted in the starch properties compared to the single modification. When the oxidation was applied first, a higher amylose and carbonyl content was noted. HMT, isolated and as a second modification, caused a more pronounced effect on viscosity profile than the oxidized starch, with an increase in paste temperature and a decrease in viscosity, breakdown and final viscosity. CONCLUSION: The results obtained in the present study reflect a decrease in water vapor permeability, although a higher tensile strength was noted when oxidation was applied, as a single and as a first modification. © 2020 Society of Chemical Industry.


Assuntos
Fabaceae/química , Extratos Vegetais/química , Amido/química , Oxirredução , Permeabilidade , Extratos Vegetais/isolamento & purificação , Amido/isolamento & purificação , Vapor/análise , Resistência à Tração , Viscosidade
10.
Plant Foods Hum Nutr ; 76(1): 90-97, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33517518

RESUMO

Jambolan is an unexplored fruit rich in bioactive compounds like anthocyanins, catechin, and gallic acid. Thus, the extraction of bioactive compounds allows adding value to the fruit. In this context, the present study reports the recovery and concentration of jambolan fruit extract by ultra and nanofiltration for the first time. Acidified water was used to extract polyphenols from the pulp and peel of jambolan. The extracts were concentrated using ultrafiltration and nanofiltration membranes with nominal molecular weight cut-off ranging from 180 to 4000 g mol-1. Total monomeric anthocyanin, total phenolic compounds, and antioxidant capacity were analyzed. Phenolic compounds were quantified, and anthocyanins were identified by high-performance liquid chromatography coupled to diode-array detection and mass spectrometry (HPLC-DAD-MS). Concentration factors higher than 4.0 were obtained for anthocyanins, gallic acid, and catechin after nanofiltration of the extracts. Other compounds such as epicatechin, p-Coumaric acid, and ferulic acid were quantified in the concentrated extract, and the main anthocyanins identified were 3,5-diglucoside: petunidin, malvidin, and delphinidin. Therefore, jambolan extract showed a high potential to be used as a natural dye and antioxidant in food products.


Assuntos
Syzygium , Antocianinas/análise , Antioxidantes , Cromatografia Líquida de Alta Pressão , Frutas/química , Fenóis/análise , Extratos Vegetais
11.
J Sci Food Agric ; 98(7): 2735-2741, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29105097

RESUMO

BACKGROUND: pH-sensitive indicator membranes, which are useful for pharmaceutical, food, and packaging applications, can be formed by encapsulating halochromic compounds within various solid supports. Accordingly, electrospinning is a versatile technique for the development of these indicators, by entrapping pH dyes within ultrafine polymer fibers. RESULTS: The ultrafine zein fibers, containing 5% (w/v) anthocyanins, had an average diameter of 510 nm. The pH-sensitive membrane exhibited color changes from pink to green when exposed to acidic and alkaline buffers, respectively. The contact angle was negligible after 10 and 2 s for neat and 5% anthocyanin-loaded zein membranes, respectively. CONCLUSION: The pH membranes exhibited color changes in a board pH range, which can potentially be used in various active packaging applications. © 2017 Society of Chemical Industry.


Assuntos
Antocianinas/química , Polímeros/química , Zeína/química , Cor , Concentração de Íons de Hidrogênio
12.
Rev Invest Clin ; 69(3): 152-158, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28613285

RESUMO

BACKGROUND: In Baja California Sur, Mexico, there are no records of dengue hemorrhagic fever in the state before 1995. Until now, there have been no published reports on the incidence rate. OBJECTIVE: To assess the incidence rate of dengue hemorrhagic fever in Baja California Sur in the last two decades. METHODS: We analyzed data on the total number of cases in the general population, incidence rate, age groups, gender, serotypes, and mortality data. RESULTS: There were epidemiological outbreaks in 2003, 2006, 2010, 2013, and 2014. The year with the highest number of registered cases was 2003 (441 cases), with the highest incidence rate of 92.52/100,000. The age groups that were primarily affected were 15-24 and 45-64 years. The serotypes of dengue virus registered during those years were DENV-1 and DENV-2. CONCLUSIONS: Dengue hemorrhagic fever in Baja California Sur has had cyclic patterns of occurrence in the last 20 years. Since 2003, the incidence rate of dengue hemorrhagic fever has greatly decreased.


Assuntos
Vírus da Dengue/isolamento & purificação , Surtos de Doenças/estatística & dados numéricos , Dengue Grave/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Dengue Grave/virologia , Adulto Jovem
13.
J Sci Food Agric ; 96(7): 2478-85, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26250365

RESUMO

BACKGROUND: The microstructure and the physical, mechanical, barrier and thermal properties of films based on different concentrations of protein isolated from croaker waste (CPI) and palm oil (PO) were analyzed. Films were elaborated by a casting technique using 2, 3 and 4 g CPI 100 g(-1) of a filmogenic solution and 0, 10 and 20 g of PO 100 g(-1) CPI. RESULT: Microstructure of the film surfaces of CPI with PO showed no presence of lipid droplets dispersed in the filmogenic matrix, although a rough surface was present. Films with 3% and 4% CPI and 20% PO had the lowest rates of water vapor permeability. When there was an addition of PO to the reduced tensile strength of the films, regardless of the concentration of CPI, this addition reduced the elongation of films with 3% and 4% CPI; however, it did not influence films with 2% CPI, which did not differ from the control film (0% OP). Thermal analysis revealed that films with the highest PO percentage had a lower initial weight loss when compared with other films, due to higher hydrophobicity. CONCLUSION: The use of protein isolate obtained from fish residues of low commercial value and palm oil is viable for the production of biodegradable films because the latter constitute good barrier properties and thermal stability. © 2015 Society of Chemical Industry.


Assuntos
Proteínas de Peixes/química , Peixes/classificação , Óleos de Plantas/química , Animais , Embalagem de Alimentos , Teste de Materiais , Membranas Artificiais , Microscopia Eletroquímica de Varredura , Óleo de Palmeira , Termogravimetria
14.
Rev Invest Clin ; 67(6): 372-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26950742

RESUMO

BACKGROUND: The State of Baja California Sur is in an arid region of Mexico, the southern half of the Baja California Peninsula. Given its aridity and physical isolation from mainland Mexico, there were no records of dengue fever in the state before 1985. Until now, no data on dengue incidence had been published. OBJECTIVE: To study some epidemiological features of dengue fever in Baja California Sur, Mexico in the last 30 years. METHODS: Total number of cases, general population, sex, age groups, serotypes, mortality, and incidence data were analyzed. RESULTS: There was a 652% increase in reported cases from 2012 through 2014. Age groups mostly affected were adults aged 15-24 and 45-64 years old. CONCLUSIONS: This study makes a thorough analysis of the incidence of dengue and makes recommendations to face the epidemiological challenge.


Assuntos
Vírus da Dengue/isolamento & purificação , Dengue/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Dengue/mortalidade , Dengue/virologia , Feminino , Humanos , Incidência , Lactente , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Sorogrupo , Adulto Jovem
15.
Dev Psychobiol ; 56(1): 12-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23129442

RESUMO

Recent findings show that developmental vitamin D deficiency leads to altered brain morphology and behavioral development in the rat offspring. We examined the effects of different dietary vitamin D levels in rat dams on behavior and biochemistry of the offspring. Females were divided into five conditions and received diets containing 0, 1,5, 3.3, 6.0, or 10.0 IU/g of vitamin D3 from mating to weaning. Offspring were tested as juveniles and as adults for anxiety, social learning and behavior, and locomotion. Results show that both deficient and excessive levels of vitamin D3 in juveniles lead to altered physiology and behavior. In juveniles but not adults, variations in vitamin D were related to variations in measures of anxiety and marginally, activity levels. For social behaviors, both juveniles and adults were affected by mothers' diets. In general, offspring of animals receiving abnormal concentrations of vitamin D showed the most deficits.


Assuntos
Comportamento Animal/efeitos dos fármacos , Colecalciferol/farmacologia , Aprendizagem/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Lactação/efeitos dos fármacos , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Comportamento Social
16.
Curr Nutr Rep ; 13(2): 280-293, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38578590

RESUMO

Estimates of dietary intake of polyphenols have been limited to specific samples from certain population groups, and different databases have been used to quantify the levels of these compounds, which makes it difficult to compare results. PURPOSE OF REVIEW: This review collated estimates of polyphenol intake from population studies including adults and elderly from different parts of the world by using a single database: Phenol-Explorer. RECENT FINDINGS: Through seven population-based studies performed in five different countries, it was possible to identify that Brazil was the country with the lowest intake of polyphenols, whereas Poland had the highest dietary intake. The most ingested subclasses of polyphenols in different countries were phenolic acids and flavonoids, and non-alcoholic beverages (coffee, tea, and orange juice) were the foods that most contributed to the intake of polyphenols. Despite the attempt to standardize this study to obtain worldwide intake estimates that could be comparable, gaps were found regarding the assessment of food consumption, standardization to obtain the polyphenol content of foods in Phenol-Explorer, calculation in aglycone equivalents, and caloric adjustment of the estimates. There is a need for more studies on the dietary polyphenols intake of representative samples of populations from different countries to collate more data on the quantities consumed and the main contributing foods.


Assuntos
Dieta , Polifenóis , Humanos , Polifenóis/análise , Idoso , Adulto , Flavonoides/análise , Brasil , Chá/química , Polônia , Pessoa de Meia-Idade , Hidroxibenzoatos
17.
Biosensors (Basel) ; 14(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38667152

RESUMO

This work reports on the surface functionalization of a nanomaterial supporting localized surface plasmon resonances (LSPRs) with (synthetic) thiolated oligonucleotide-based biorecognition elements, envisaging the development of selective LSPR-based DNA biosensors. The LSPR thin-film transducers are composed of noble metal nanoparticles (NPs) embedded in a TiO2 dielectric matrix, produced cost-effectively and sustainably by magnetron sputtering. The study focused on the immobilization kinetics of thiolated oligonucleotide probes as biorecognition elements, followed by the evaluation of hybridization events with the target probe. The interaction between the thiolated oligonucleotide probe and the transducer's surface was assessed by monitoring the LSPR signal with successive additions of probe solution through a microfluidic device. The device was specifically designed and fabricated for this work and adapted to a high-resolution LSPR spectroscopy system with portable characteristics. Benefiting from the synergetic characteristics of Ag and Au in the form of bimetallic nanoparticles, the Au-Ag/TiO2 thin film proved to be more sensitive to thiolated oligonucleotide binding events. Despite the successful surface functionalization with the biorecognition element, the detection of complementary oligonucleotides revealed electrostatic repulsion and steric hindrance, which hindered hybridization with the target oligonucleotide. This study points to an effect that is still poorly described in the literature and affects the design of LSPR biosensors based on nanoplasmonic thin films.


Assuntos
Técnicas Biossensoriais , Ouro , Nanopartículas Metálicas , Oligonucleotídeos , Prata , Ressonância de Plasmônio de Superfície , Titânio , Titânio/química , Ouro/química , Prata/química , Nanopartículas Metálicas/química , Oligonucleotídeos/química , Compostos de Sulfidrila/química , DNA , Hibridização de Ácido Nucleico
18.
Foods ; 13(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731745

RESUMO

There is a growing interest in exploring new natural sources of colorants. This study aimed to extract anthocyanins from broken black bean hulls (Phaseolus vulgaris L.) by modifying water with a eutectic mixture (choline chloride:citric acid (ChCl:Ca)). Ultrasound-assisted extraction (UAE) was employed and optimized in terms of temperature (30-70 °C), ultrasound power (150-450 W), and eutectic mixture concentration in water (1-9% (w/v)), resulting in an optimal condition of 66 °C, 420 W, and 8.2% (w/v), respectively. The main quantified anthocyanins were delphinidin-3-O-glycoside, petunidin-3-O-glycoside, and malvidin-3-O-glycoside. The half-life of the anthocyanins at 60 °C increased twelvefold in the eutectic mixture extract compared to the control, and when exposed to light, the half-life was 10 times longer, indicating greater resistance of anthocyanins in the extracted eutectic mixture. Additionally, the extracts were concentrated through centrifuge-assisted cryoconcentration, with the initial cycle almost double the extract value, making this result more favorable regarding green metrics. The first concentration cycle, which showed vibrant colors of anthocyanins, was selected to analyze the color change at different pH levels. In general, the technology that uses eutectic mixtures as water modifiers followed by cryoconcentration proved to be efficient for use as indicators in packaging, both in quantity and quality of anthocyanins.

19.
Int J Biol Macromol ; 275(Pt 1): 133386, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38914407

RESUMO

Biodegradable starch foam trays offer an eco-friendly substitute for petroleum-based single-use packaging, notably polystyrene foams. However, they lack flexibility, tensile strength, and water-sensitivity, addressable through lignocellulosic reinforcement. This study aimed to develop biodegradable starch foam trays filled with different food-chain side streams for sustainable alternative packaging. Corncob, soybean straw, cassava peel, araucaria seed hull, yerba mate stalks and yerba mate leaves petiole were collected, dried and ground to <250 µm. The trays were filled with 13 % (w/w) of each food-chain side streams and produced by hot molding. The trays morphology, moisture, water activity (aw), thickness, bulk density, tensile strength, elongation at break, Young's modulus, bending strength, maximum deflection, and sorption isotherms were investigated. Reinforcements slightly increased the foams bulk density, reduced the tensile strength and maximum deflection and while bending strength increased from 0.20 MPa to 1.17-1.80 MPa. The elasticity modulus decreased by adding any filling, that resulted in ductility improvement; however, these packaging have moisture-sensitive material especially for aw higher than 0.52, which drives the use recommendation for dry products storage or shipping/transport. The biodegradable starch foam trays filled with side streams were successfully produced and offer excellent alternative to petroleum-based packaging low-density material with bending strength improved.


Assuntos
Amido , Resistência à Tração , Amido/química , Água/química , Embalagem de Alimentos/métodos , Manihot/química
20.
Arch Virol ; 158(11): 2409-13, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23732928

RESUMO

VPMS1 is a Vibrio parahaemolyticus lytic phage isolated from a marine clam. The 42.3-kb genome was predicted to encode 53 proteins. Comparison of the VPMS1 DNA genome with known phage genomes revealed no similarity; hence, it represents a new VP phage, organized into three differently oriented modules. The module for packaging covers 12 % of the genome, the module for structure covers 31 %, and the module for replication and regulation covers 48 %. The G + C content was 44.67 %. The coding region corresponds to 91 % of the genome, and 9 % apparently does not encode any protein. Thirty genes, constituting 57 % of the genome, had significant similarity to some reported proteins in the protein database; 23 genes, constituting 43 % of the genome, showed no significant homology to any reported protein, and these could be new proteins whose hypothetical functions can be deduced from their position in the genome.


Assuntos
Bacteriófagos/genética , Bacteriófagos/fisiologia , Genoma Viral , Lisogenia , Análise de Sequência de DNA , Vibrio parahaemolyticus/virologia , Animais , Bacteriófagos/isolamento & purificação , Bacteriófagos/ultraestrutura , Composição de Bases , Bivalves/virologia , Dados de Sequência Molecular , Proteínas Virais/genética
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