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1.
Front Psychiatry ; 15: 1321207, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863617

RESUMO

Background: The concept of entrapment has been highlighted as a transdiagnostic element that manifests itself in disorders such as depression, anxiety, and suicidal ideation. Although research has been conducted in different contexts independently, a comprehensive multi-country study to assess gender differences in entrapment through network analysis has not yet been carried out. The objective of this study was to evaluate the entrapment network in men and women at the multinational level. Methods: A sample of 2,949 participants, ranging in age from 18 to 73 years from six countries (Germany, Iran, Spain, Slovakia, El Salvador, and Peru), was considered. They completed the entrapment scale. A network analysis was performed for both men and women to identify the connectivity between indicators and the formation of clusters and domains, in addition to the centrality assessment in both sex groups. Results: The study findings revealed the presence of a third domain focused on external interpersonal entrapment in the network of men and women. However, in relation to the interconnectivity between domains, variations were evidenced in both networks, as well as in centrality, it was reported that men present a greater generalized entrapment in various aspects of life, while women tend to experience a more focused entrapment in expressions of intense emotional charge. Conclusion: The multinational study identified variations in the structure of entrapment between genders, with three domains (internal, external, and external-interpersonal) and differences in the interaction of indicators and groupings, as well as discrepancies in centrality.

2.
Diagnostics (Basel) ; 14(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611609

RESUMO

Objective: The aim of this study was to describe the main anatomical variants and morphofunctional alterations in the lower limb that compress surrounding nervous structures in the gluteal region, thigh region, and leg and foot region. Methods: We searched the Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to October 2023. An assurance tool for anatomical studies (AQUA) was used to evaluate methodological quality, and the Joanna Briggs Institute assessment tool for case reports was also used. Forest plots were generated to assess the prevalence of variants of the gluteal region, thigh, and leg. Results: According to the forest plot of the gluteal region, the prevalence was 0.18 (0.14-0.23), with a heterogeneity of 93.52%. For the thigh region, the forest plot presented a prevalence of 0.10 (0.03-0.17) and a heterogeneity of 91.18%. The forest plot of the leg region was based on seven studies, which presented a prevalence of 0.01 (0.01-0.01) and a heterogeneity of 96.18%. Conclusions: This review and meta-analysis showed that, in studies that analyzed nerve compressions, the prevalence was low in the thigh and leg regions, while in the gluteal region, it was slightly higher. This is mainly due to the PM region and its different variants. We believe that it is important to analyze all the variant regions defined in this study and that surgeons treating the lower limb should be attentive to these possible scenarios so that they can anticipate possible surgical situations and thus avoid surgical complications.

3.
Psicol Reflex Crit ; 37(1): 3, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236551

RESUMO

BACKGROUND: Entrapment is the feeling of wanting to leave an unbearable situation but believing that there are no options to do so. An Arabic entrapment Scale will assist healthcare professionals in the region in the prevention of suicide as the tool is tailored to the specific sociocultural context, which would enhance entrapment detection. OBJECTIVE: In the current study, we aim to evaluate the psychometric properties of a translated Arabic version of the Entrapment Scale Short Form (E-SF). METHODS: Three hundred eighty-nine Lebanese citizens were enrolled in this cross-sectional study. RESULTS: The mean age of participants was 23.03 years (SD = 2.93), 69.4% being women. To examine the factor structure of the entrapment scale, we used an exploratory-to-confirmatory factor analysis (EFA-to-CFA) strategy. EFA and CFA results indicated that the fit of the unidimensional model of the Arabic Entrapment Scale (A-ES) was generally acceptable. Composite reliability of scores was adequate in the total sample (ω = .87). All indices suggested that configural, metric, and scalar invariance was supported across genders. Entrapment was positively and significantly correlated with suicidal ideation, alcohol use disorder, psychological distress, and orthorexia nervosa, suggesting convergent and divergent validity. CONCLUSION: The A-ES was found to be a valid and reliable tool to assess the degree of entrapment in Lebanese young adults. The A-ES will assist healthcare professionals in the region in the prevention of suicide as the tool is tailored to the specific sociocultural context, which would enhance entrapment detection.

4.
Psicol. reflex. crit ; 37: 3, 2024. tab
Artigo em Inglês | LILACS, Index Psicologia - Periódicos | ID: biblio-1558764

RESUMO

Background Entrapment is the feeling of wanting to leave an unbearable situation but believing that there are no options to do so. An Arabic entrapment Scale will assist healthcare professionals in the region in the prevention of suicide as the tool is tailored to the specific sociocultural context, which would enhance entrapment detection. Objective In the current study, we aim to evaluate the psychometric properties of a translated Arabic version of the Entrapment Scale Short Form (E-SF). Methods Three hundred eighty-nine Lebanese citizens were enrolled in this cross-sectional study. Results The mean age of participants was 23.03 years (SD = 2.93), 69.4% being women. To examine the factor structure of the entrapment scale, we used an exploratory-to-confirmatory factor analysis (EFA-to-CFA) strategy. EFA and CFA results indicated that the fit of the unidimensional model of the Arabic Entrapment Scale (A-ES) was generally acceptable. Composite reliability of scores was adequate in the total sample (ω = .87). All indices suggested that configural, metric, and scalar invariance was supported across genders. Entrapment was positively and significantly correlated with suicidal ideation, alcohol use disorder, psychological distress, and orthorexia nervosa, suggesting convergent and divergent validity. Conclusion The A-ES was found to be a valid and reliable tool to assess the degree of entrapment in Lebanese young adults. The A-ES will assist healthcare professionals in the region in the prevention of suicide as the tool is tailored to the specific sociocultural context, which would enhance entrapment detection. (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Psicometria , Traduções , Inquéritos e Questionários , Ideação Suicida , Encarceramento/psicologia , Saúde Mental , Estudos Transversais , Prevenção do Suicídio , Líbano
5.
Front Immunol ; 14: 1282278, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38115994

RESUMO

Introduction: Toxoplasma gondii, responsible for causing toxoplasmosis, is a prevalent food and waterborne pathogen worldwide. It commonly infects warm-blooded animals and affects more than a third of the global human population. Once ingested, the parasite enters the host's small intestine and rapidly disseminates throughout the body via the bloodstream, infiltrating various tissues. Leukocyte-driven responses are vital against T. gondii, with neutrophils playing a dual role: swiftly recruited to infection sites, releasing inflammatory mediators, and serving as a replication hub and Trojan horses, aiding parasite spread. Neutrophils from various hosts release extracellular traps (NETs) against the protozoan. However, gaps persist regarding the mechanisms of NETs production to parasite and their significance in infection control. This study investigates the interplay between human neutrophils and T. gondii, exploring dynamics, key molecules, and signaling pathways involved in NETs production upon protozoan challenge. Methods and Results: Using confocal and electron microscopy, live cell imaging, pharmacological inhibitors, and DNA quantification assays, we find that human neutrophils promptly release both classical and rapid NETs upon pathogen stimulation. The NETs structure exhibits diverse phenotypes over time and is consistently associated with microorganisms. Mechanisms involve neutrophil elastase and peptidylarginine deiminase, along with intracellular calcium signaling and the PI3K pathway. Unexpectedly, human traps do not diminish viability or infectivity, but potentially aid in capturing parasites for subsequent neutrophil phagocytosis and elimination. Discussion: By revealing NETs formation mechanisms and their nuanced impact on T. gondii infection dynamics, our findings contribute to broader insights into host-pathogen relationships.


Assuntos
Armadilhas Extracelulares , Toxoplasma , Toxoplasmose , Animais , Humanos , Armadilhas Extracelulares/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Toxoplasmose/metabolismo , Neutrófilos/metabolismo , Toxoplasma/fisiologia
6.
Foods ; 12(20)2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37893763

RESUMO

Sulforaphane (SFN) is a bioactive compound widely studied for its potential applications in pharmaceutical, nutraceutical, and food industries since it offers health benefits due to its nature as a Phase 2 enzyme inducer. Its application in the food industry has been limited because SFN is unstable at high temperatures in an aqueous milieu. An option to increase SFN stability and protect it from thermal degradation is microencapsulation. The aim of this work was to optimize a microencapsulation process using oil-in-water emulsion to increase the thermal stability of SFN. The operation conditions that gave the highest entrapment efficiency were determined via experimental design and response surface methodology. Thermal degradation of microencapsulated SFN was studied at 37, 50, 60, and 70 °C. The optimum microencapsulation conditions were 8 min stirring, SFN/Gum Arabic ratio of 0.82, and surfactant/oil ratio of 1.0, resulting in an entrapment efficiency of 65%, which is the highest reported so far. The thermal stability of microencapsulated SFN was greatly enhanced compared with free SFN, with a 6-fold decrease in the degradation kinetic constant and a 41% increase in the activation energy. These results will contribute to a more efficient incorporation of SFN in various food matrices and explore new microencapsulation technologies to maximize the efficiency and stability of SFN.

7.
Int Orthop ; 47(11): 2781-2786, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37516678

RESUMO

PURPOSE: In the literature, we find that patients with lacertus syndrome (LS), proximal median nerve compression at the elbow, present subjective improvement of thumb, and index flexion strength after lacertus fibrosus (LF) release. The aim of this study is to objectively evaluate the immediate change in intraoperative flexion strength after LF release. METHOD: We retrospectively reviewed prospectively collected data of a cohort of 24 patients with a double crush syndrome of the median nerve with no response to conservative treatment. All patients had surgery with LF and carpal tunnel release (CTR) under wide-awake local anaesthesia and no tourniquet (WALANT) and were evaluated intraoperatively with a dynamometer immediately before and after LF release. Flexor digitorum profundus of the second finger (FDP2) and Flexor pollicis longus (FPL) were tested in peak strength to failure. The primary outcome was the percentage of change in strength before and after the release in both assessed muscles. CTR was done after evaluating the change in flexor strength. RESULTS: A percentage of 79.2 women with an average age of 43.3 years. The average strength of FDP2 before LF release was 15.5 pounds (lbs.) (7.0 kg) (SD, 7.2 lbs (3.3 kg)) and 27.1 lbs. (12.2 kg) (SD, 7.1 lbs. (3.2 kg)) after LF release, which corresponds to a 96% (SD, 70%) change in strength (p=0.000). For FPL, the average pre-release strength was 17.7 lbs. (8.0kg) (SD, 4.8 lbs. (2.2 kg)) and 27.4 lbs. (12.4 kg) (SD, 5.2 lbs. (2.4 kg)) post-release, this corresponded to a 65% (SD, 38%) change in strength (p=0.000). CONCLUSIONS: Peak strength to failure in FDP2 and FPL has an immediate significant recovery after LF surgical release in patients with Lacertus syndrome. LEVEL OF EVIDENCE: IV, retrospective study.


Assuntos
Síndrome do Túnel Carpal , Articulação do Cotovelo , Humanos , Feminino , Adulto , Cotovelo , Estudos Retrospectivos , Nervo Mediano , Tendões , Articulação do Cotovelo/cirurgia , Síndrome do Túnel Carpal/cirurgia
8.
Nanomaterials (Basel) ; 13(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36678096

RESUMO

Previous studies have suggested that graphene oxide (GO) has some antiviral capacity against some enveloped viruses, including SARS-CoV-2. Given this background, we wanted to test the in vitro antiviral ability to GO using the viral plaque assay technique. Two-dimensional graphene oxide (GO) nanoparticles were synthesized using the modified Hummers method, varying the oxidation conditions to achieve nanoparticles between 390 and 718 nm. The antiviral activity of GO was evaluated by experimental infection and plaque formation units assay of the SARS-CoV-2 virus in VERO cells using a titrated viral clinical isolate. It was found that GO at concentrations of 400 µg/mL, 100 µg/mL, 40 µg/mL, and 4 µg/mL was not toxic to cell culture and also did not inhibit the infection of VERO cells by SARS-CoV-2. However, it was evident that GO generated a novel virus entrapment phenomenon directly proportional to its concentration in the suspension. Similarly, this effect of GO was maintained in assays performed with the Zika virus. A new application for GO nanoparticles is proposed as part of a system to trap viruses in surgical mask filters, air conditioning equipment filters, and air purifier filters, complemented with the use of viricidal agents that can destroy the trapped viruses, an application of broad interest for human beings.

9.
Biosci. j. (Online) ; 39: e39009, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1415877

RESUMO

1,4-alpha-D-glucan glucanohydrolase is among the most widely used commercial hydrolytic enzymes acting randomly on the glycosidic linkages of starch resulting in its saccharification and liquefaction. Its applicability in different industries can be improved by enhancing its stability and reusability. Therefore, in the present study attempts have been made to enhance the industrial applicability of 1,4-alpha-D-glucan glucanohydrolase from Bacillus subtilis KIBGE-HAR by adapting immobilization technology. The study developed mechanically stable, enzyme containing gel-frameworks using two support matrices including agar-agar, a natural polysaccharide and polyacrylamide gel, a synthetic organic polymer. These catalytic gel-scaffolds were compared with each other in terms of kinetics and stability of entrapped 1,4-α-D-glucan glucanohydrolase. In case of polyacrylamide gel, Km value for immobilized enzyme increased to 7.95 mg/mL, while immobilization in agar-agar resulted in decreased Km value i.e 0.277 mg/mL as compared to free enzyme. It was found that immobilized enzyme showed maximum activity at 70 °C in both the supports as compared to free enzyme having maximum activity at 60 °C. Immobilized 1,4-α-D-glucan glucanohydrolase exhibited no change in optimal pH 7.0 before and after entrapment in polyacrylamide gel and agar-agar. The enzyme containing gel-scaffold was found suitable for repeated batches of starch liquefaction in industrial processes. Agar-agar entrapped 1,4-α-D-glucanglucanohydrolase was capable to degrade starch up to seven repeated operational cycles whereas polyacrylamide entrapped enzyme conserved its activity up to sixth operational cycle.


Assuntos
Polímeros , Cinética , Amilases
10.
Arq. bras. neurocir ; 42(1): 40-51, 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1570235

RESUMO

Peripheral nerve injuries vary in length and severity, and they can occur secondary to trauma, compression and ischemia, leading to both motor and sensory neurological deficits. Nerve compression can occur in both the upper and lower limbs. These injuries can affect the quality of life, including the total or partial loss of the individual's productive capacity. The diagnostic methods are based on clinical criteria, but they may also include imaging and electroneurophysiological studies. A clinical examination using the Tinel and Phalen tests, for example, may suggest carpal tunnel syndrome. Complementary exams are used to confirm the diagnosis and rule out other possibilities, and the most used are electroneuromyography (ENMG), computed tomography (CT), magnetic resonance imaging (MRI), and ultrasonography (US). Depending on the type of injury, recovery may be spontaneous or may require conservative or surgical treatment.


As lesões nervosas periféricas variam em extensão e gravidade, as quais podem ocorrer secundárias a trauma, compressão e isquemia, e acarretam déficits neurológicos tanto motores quanto sensoriais. A compressão nervosa pode ocorrer nos membros superiores e inferiores. Estas lesões podem afetar a qualidade de vida, incluindo a perda total ou parcial da capacidade produtiva do indivíduo. Os métodos diagnósticos são baseados em critérios clínicos, mas também podem incluir métodos de imagem e estudos eletroneurofisiológicos. O exame clínico por meio dos testes de Tinel e de Phalen, por exemplo, pode sugerir síndrome do túnel do carpo. Os exames complementares servem para confirmar o diagnóstico e descartar outras possibilidades, sendo os mais utilizados a eletroneuromiografia (ENMG), a tomografia computadorizada (TC), a ressonância magnética (RM) e a ultrassonografia (US). De acordo com o tipo da lesão, a recuperação pode ser espontânea ou necessitar de tratamento conservador ou cirúrgico.

11.
Food Res Int ; 162(Pt A): 111984, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461227

RESUMO

The generation albumin-based nanocarriers by precipitation from solution has great interest in the formulation of advanced nutritional products. Microfluidic techniques enable the implementation of low energy and continuum processes, with fast mass transfer and homogeneous mixing at the microscale. Here we describe the microfluidic generation of curcumin-loaded alpha lactalbumin nanoparticles in a simple and inexpensive way, by using off-the-shelf devices designed to produce solvent-shifting nanoprecipitation in core-sheath flows driven by gravity, which has not been reported before. Nanoparticles were characterized by dynamic light scattering, electron microscopy, and infrared spectroscopy. The microfluidic operating conditions were defined by theory and experiments, and the critical parameters controlling the nanoparticles diameter were identified. The prepared nanoparticles resulted practically monodisperse, the curcumin entrapment efficiency was about 40 %, and almost 70 % of the bioactive was gradually delivered in release experiments. The proposed methodology is a promising route to scale up the microfluidic elaboration of nanoparticles for the entrapment of active ingredients.


Assuntos
Curcumina , Nanopartículas , Microfluídica , Albuminas , Lactalbumina
12.
J Vasc Surg Cases Innov Tech ; 8(2): 248-250, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35516166

RESUMO

Popliteal artery entrapment syndrome is a rare source of claudication in young people. We present the case of a 15-year-old male athlete who presented with intermittent numbness of his right foot with exertion. Imaging revealed classic compression from a right type III popliteal artery entrapment. The left popliteal artery was chronically occluded with a large collateral vessel. He underwent release of the accessory bands of the gastrocnemius muscle with significant arteriolysis on the right side via a posterior approach. Chronic popliteal artery entrapment can be treated from a posterior approach, resulting in arterial occlusion and will be asymptomatic if well collateralized.

13.
Protein J ; 41(2): 274-292, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35438380

RESUMO

ß-Glucosidase is widely used in several industrial segments, among which we can highlight the pharmaceutical industry, beverages, biofuels, animal feed production, and the textile industry. The great applicability of this enzyme, associated with the high cost of its production, justifies the need to find ways to make its use economically viable on an industrial scale. Through enzyme immobilization, the biocatalyst can be reused more than once, without great impact on its catalytic activity, and higher operational and storage stabilities can be achieved as compared to the free form. Accordingly, this review brings information about different techniques and supports that have been studied in the immobilization of cellulases with a focus on ß-glucosidase, as well as the application of these immobilized systems to supplement commercial mixtures.


Assuntos
Enzimas Imobilizadas , beta-Glucosidase , Biocombustíveis , Estabilidade Enzimática
14.
Hand (N Y) ; 17(5): NP1-NP5, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35109697

RESUMO

Isolated compression of the recurrent motor branch of the median nerve is an uncommon condition encontered in the daily life of the hand surgeon. Its early identification and correction can optimize functional outcomes. Among the few causes described, there are only 2 case reports of compression by fascial bands. We present a case of isolated compression of the recurrent motor branch of the median nerve secondary to anomalous fascial bands in a 34-year-old male patient, with significant atrophy of the thenar musculature of the right hand. Electroneuromyography showed isolated involvement of abductor pollicis brevis, with no sensory changes. The patient underwent exploration and decompression, recovering opposition and thumb function in 6 months.


Assuntos
Mãos , Nervo Mediano , Adulto , Mãos/inervação , Humanos , Masculino , Nervo Mediano/cirurgia , Músculo Esquelético , Polegar
15.
Muscle Nerve ; 65(5): 590-593, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35083751

RESUMO

INTRODUCTION/AIMS: Focal peripheral neuropathies are infrequently seen in pediatric patients. The COVID-19 pandemic has disrupted normal life for many people, including complete lockdowns and school closing for long periods of time in many countries, which prompted children to stay at home. Our aim is to assess whether there has been an increased incidence of focal compressive peripheral neuropathies in the pediatric population during COVID-19-associated lockdown. METHODS: Clinical, electrophysiological, and imaging characteristics were reviewed for patients referred to the electrodiagnostic (EDx) laboratory with suspicion of a focal neuropathy. The incidence of focal compressive peripheral neuropathies seen during the period of March to September 2020 was compared with the same time period in 2019. RESULTS: An increased incidence of focal neuropathies was seen in 2020 (31%) compared with 2019 (6.8%). During 2020, 7 fibular (peroneal) mononeuropathies and 2 ulnar neuropathies were diagnosed. Most patients with focal neuropathies were underweight and acknowledged prolonged screen time periods. Electrophysiological findings consisted of mostly demyelinating lesions with an overall good clinical outcome. DISCUSSION: In this study we raise awareness about a possible increased incidence of focal compressive peripheral neuropathies in children during COVID-19-associated lockdown, which may be prevented with changing positions during sedentary activities.


Assuntos
COVID-19 , Mononeuropatias , Síndromes de Compressão Nervosa , Doenças do Sistema Nervoso Periférico , Argentina/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Criança , Controle de Doenças Transmissíveis , Humanos , Incidência , Mononeuropatias/complicações , Síndromes de Compressão Nervosa/diagnóstico , Pandemias , Doenças do Sistema Nervoso Periférico/complicações , Doenças do Sistema Nervoso Periférico/epidemiologia , Quarentena , Comportamento Sedentário
16.
J. Transcatheter Interv ; 30: eA202202, 20220101. ilus; tab
Artigo em Inglês, Português | LILACS-Express | LILACS | ID: biblio-1396024

RESUMO

Tecnologias mais avançadas, drogas melhores e profissionais mais experientes contribuíram para desfechos otimizados das intervenções coronarianas percutâneas complexas. As complicações com impacto significativo na sobrevida do paciente e alto custo para o sistema de saúde não foram totalmente eliminadas pelos procedimentos modernos de intervenções coronarianas percutâneas. Os procedimentos preventivos e a experiência do operador são as únicas formas de se evitarem os efeitos colaterais graves das intervenções coronarianas percutâneas. As dissecções, o fechamento abrupto da artéria, a perfuração coronariana, o non-reflow, a embolia gasosa, a deformação do stent, a embolização do dispositivo e o aprisionamento da ogiva de aterectomia rotacional são algumas das complicações abordadas neste artigo.


More advanced technology, better drugs and more experienced operators have contributed to improved complex percutaneous coronary intervention outcomes. Complications with significant impact on patient survival and healthcare costs have not been completely eliminated by modern percutaneous coronary intervention procedures. Professional expertise and consistent preventive procedures are the only ways to avoid severe side effects of percutaneous coronary intervention. Dissections, abrupt arterial closure, coronary perforation, no-reflow, air embolism, stent deformation, device embolization, and rotating atherectomy burr entrapment are some of the periprocedural complications covered in this article.

17.
Int J Biol Macromol ; 183: 1959-1970, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34090851

RESUMO

The widespread application of soluble enzymes in industrial processes is considered restrict due to instability of enzymes outside optimum operating conditions. For instance, enzyme immobilization can overcome this issue. In fact, chitosan-based nanofibers have outstanding properties, which can improve the efficiency in enzyme immobilization and the stability of enzymes over a wide range of operating conditions. These properties include biodegradability, antimicrobial activity, non-toxicity, presence of functional groups (amino and hydroxyl), large surface area to volume ratio, enhanced porosity and mechanical properties, easy separations and reusability. Therefore, the present review explores the advantages and drawbacks concerning the different methods of enzyme immobilization, including adsorption, cross-linking and entrapment. All these strategies have questions that still need to be addressed, such as elucidation of adsorption mechanism (physisorption or chemisorption); effect of cross-linking reaction on intramolecular and intermolecular interactions and the effect of internal and external diffusional limitations on entrapment of enzymes. Moreover, the current review discusses the challenges and prospects regarding the application of chitosan-based nanofibers in enzyme immobilization, towards maximizing catalytic activity and lifetime.


Assuntos
Anti-Infecciosos/química , Quitosana/química , Enzimas Imobilizadas/química , Adsorção , Catálise , Estabilidade Enzimática , Nanofibras , Porosidade
18.
Biomolecules ; 11(5)2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947162

RESUMO

Nowadays, enzyme-mediated processes offer an eco-friendly and efficient alternative to the traditional multistep and environmentally harmful chemical processes. Herein we report the enzymatic synthesis of cladribine by a novel 2'-deoxyribosyltransferase (NDT)-based combined biocatalyst. To this end, Lactobacillus delbrueckii NDT (LdNDT) was successfully immobilized through a two-step immobilization methodology, including a covalent immobilization onto glutaraldehyde-activated biomimetic silica nanoparticles followed by biocatalyst entrapment in calcium alginate. The resulting immobilized derivative, SiGPEI 25000-LdNDT-Alg, displayed 98% retained activity and was shown to be active and stable in a broad range of pH (5-9) and temperature (30-60 °C), but also displayed an extremely high reusability (up to 2100 reuses without negligible loss of activity) in the enzymatic production of cladribine. Finally, as a proof of concept, SiGPEI 25000-LdNDT-Alg was successfully employed in the green production of cladribine at mg scale.


Assuntos
Cladribina/metabolismo , Lactobacillus delbrueckii/enzimologia , Transferases/química , Transferases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biocatálise , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glutaral/química , Química Verde , Concentração de Íons de Hidrogênio , Dióxido de Silício/química , Temperatura
19.
Molecules ; 26(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922853

RESUMO

Ferulated polysaccharides such as pectin and arabinoxylan form covalent gels which are attractive for drug delivery or cell immobilization. Saccharomyces boulardii is a probiotic yeast known for providing humans with health benefits; however, its application is limited by viability loss under environmental stress. In this study, ferulated pectin from sugar beet solid waste (SBWP) and ferulated arabinoxylan from maize bioethanol waste (AX) were used to form a covalent mixed gel, which was in turn used to entrap S. boulardii (2.08 × 108 cells/mL) in microbeads using electrospray. SBWP presented a low degree of esterification (30%), which allowed gelation through Ca2+, making it possible to reduce microbead aggregation and coalescence by curing the particles in a 2% CaCl2 cross-linking solution. SBWP/AX and SBWP/AX+ S. boulardii microbeads presented a diameter of 214 and 344 µm, respectively, and a covalent cross-linking content (dimers di-FA and trimer tri-FA of ferulic acid) of 1.15 mg/g polysaccharide. The 8-5', 8-O-4'and 5-5'di-FA isomers proportions were 79%, 18%, and 3%, respectively. Confocal laser scanning microscopy images of propidium iodide-stained yeasts confirmed cell viability before and after microbeads preparation by electrospray. SBWP/AX capability to entrap S. boulardii would represent an alternative for probiotic immobilization in tailored biomaterials and an opportunity for sustainable waste upcycling to value-added products.


Assuntos
Pectinas/química , Saccharomyces boulardii/isolamento & purificação , Xilanos/química , Portadores de Fármacos/química , Lacase/metabolismo
20.
Curr Med Imaging ; 17(11): 1340-1349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33511928

RESUMO

BACKGROUND: Ultrasonography is a diagnostic resource that serves as a complement in the evaluation of patients with carpal tunnel syndrome. The correlation of ultrasonography findings with nerve conduction studies can serve to classify new phenotypes and to evaluate therapeutic responses. OBJECTIVES: To determine the diagnostic sensitivity of ultrasound, the correlation between the diameter of the nerve (CSA) against the motor and sensitive latencies, and the capacity to differentiate the mild, moderate and severe degrees of the electrophysiological classification of carpal tunnel syndrome. METHODS: A cross-sectional study with prospective data collection was carried out. An ultrasonography system with a 15 MHz transducer was used. Nerve conduction studies of the median nerve were performed with conventional techniques. Data from the most symptomatic hand were used. Determination of the correlations of nerve diameter with motor and sensitive latencies of the median nerve was performed in four age groups: <40(n=11), 40-54 (n=47), 55-70 (n=42) y >70(n=27). RESULTS: A total of 127 patients were evaluated (average age = 58.2 years: minimum = 26; maximum = 85; SD = 13.4); 109 (85.8%) were female patients. According to the electrophysiological classification, 40 (31.5%) were mild ; 60 (47.2%) were moderate ; and 27 (21.3%) were severe . Significant differences in the area of the median nerve were found between the electrophysiological types (mild, moderate and severe; p = 0.000). The diagnostic sensitivity of ultrasonography differed for each age group. In general, the diagnostic sensitivity was high in patients with severe cases and low for mild cases. The capacity for ultrasonography to classify the degrees of electrophysiological severity was different for each age group. For patients above 70 years and in the age group of 40 to 54 years, the CSA did not differentiate the electrophysiologically moderate cases from the severe ones. CONCLUSION: There is a well-defined and significant correlation between nerve conduction studies and median nerve diameter in patients with Carpal Tunnel Syndrome. However, it shows that the exclusive use of the ultrasonographic measurement of the cross-sectional area through the inlet of the carpal tunnel would not be enough to confirm or rule out an entrapment of the median nerve through the carpal tunnel, nor to predict in every case their electrophysiological severity.


Assuntos
Síndrome do Túnel Carpal , Nervo Mediano , Adulto , Síndrome do Túnel Carpal/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Nervo Mediano/diagnóstico por imagem , Pessoa de Meia-Idade , Condução Nervosa , Ultrassonografia
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