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1.
Appl Microbiol Biotechnol ; 107(14): 4553-4566, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37272940

RESUMO

Due to the complex composition of lichenan, lichenase alone cannot always hydrolyze it efficiently. Carbohydrate-binding modules (CBMs) and lytic polysaccharide monooxygenases (LPMOs) have been confirmed to increase the hydrolysis efficiency of lichenases. However, their practical application was hampered by the complex and costly preparation procedure, as well as the poor stability of LPMOs. Herein, we discovered a novel and stable auxiliary protein named SCE to boost the hydrolysis efficiency. SCE was composed of SpyCatcher (SC) and elastin-like polypeptides (ELPs) and could be easily and cheaply prepared. Under the optimal conditions, the boosting degree for SCE/lichenase was 1.45, and the reducing sugar yield improved by nearly 45%. The results of high-performance liquid chromatography (HPLC) indicated that SCE had no influence on the hydrolysis pattern of lichenase. Through the experimental verification and bioinformatics analysis, we proposed the role of SCE in promoting the interaction between the lichenase and substrates. These findings endow SC with a novel function in binding to insoluble lichenan, paving the way for biomass degradation and biorefinery. KEY POINTS: • A novel self-purification auxiliary protein that could boost the hydrolysis efficiency of lichenase has been identified. • The protein is highly produced, simple to prepare, well stable, and does not require any external electron donor. • The novel function of SpyCatcher in binding to insoluble lichenan was first demonstrated.


Assuntos
Glucanos , Glicosídeo Hidrolases , Biomassa , Glucanos/química , Glicosídeo Hidrolases/metabolismo , Polissacarídeos
2.
J Infect Dis ; 225(5): 785-792, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34850049

RESUMO

BACKGROUND: Despite high vaccine coverage, an increase in breakthrough coronavirus disease 2019 (COVID-19) infections, prompted administration of a third BNT162b2 dose to people aged >60 years in Israel since July 2021. Here, we report real-world immunogenicity following third dose. METHODS: Overall, 208 healthcare workers aged >60 years were included. Paired pre- and post-second and/or third dose immunoglobulin G (IgG) and neutralizing antibody titers were compared. A subpopulation of low responders to the second dose was also tested for T-cell activation. For 25 paired serum samples, we tested neutralization of wild-type vs neutralization of Delta and Lambda variants, pre- and post-third dose. Active surveillance of vaccine adverse events was conducted through surveys. RESULTS: A pronounced immune response was observed following the third dose, including a 33-fold and 51-fold increase in IgG and neutralizing antibody, respectively. The neutralizing antibody levels post-third dose were 9.34 times higher than post-second dose (geometric mean titer, 2598 [95% confidence interval {CI}, 2085-3237] vs 207 [95% CI, 126-339]). Nine previously low responders had a significant antibody increase post-third dose, and 7 of 9 showed increase in T-cell activation. Additionally, sera obtained post-third dose highly and comparably neutralized the wild-type and Delta and Lambda variants. Of 1056 responders to the adverse-event survey, none had serious events. CONCLUSIONS: We demonstrate a rapid and broad immune response to the third BNT162b2 dose in individuals >60 years of age.


Assuntos
Vacina BNT162/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Imunogenicidade da Vacina , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacina BNT162/administração & dosagem , Vacina BNT162/efeitos adversos , COVID-19/epidemiologia , COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , Feminino , Pessoal de Saúde , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , RNA Mensageiro , SARS-CoV-2
3.
Foods ; 9(3)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197327

RESUMO

Arthrospira platensis, commercially known as Spirulina, is a fresh-water cyanobacterium that has been gaining increasing attention in recent years due to its high biological and nutritional value. For this reason, it has been employed in several food applications, to obtain or enhance functional and technological properties of cheese, yogurt, bread, cookies or pasta. The aim of this work was to evaluate the potential boosting effect of two different concentrations (0.25% and 0.50% w/v) of A. platensis on the fermentation capability of several starter lactic acid bacteria (LAB) strains, 1 probiotic and 4 commercial mix culture. These strains were used to ferment three different substrates and their fermentation behaviors were evaluated by impedance analyses together with rheological and color measurements. In tryptic soy broth (TSB), the A. platensis boosting effect was significantly higher if compared to yeast extract for all the starter LAB strains except for Lb. casei, which was equally stimulated. Different results were found when the same LAB strains were cultivated in SSM. The most evident boosting effect was found for S. thermophilus and Lb. casei. LAB growth was promoted by A. platensis, confirming that it could be a useful tool in the production of novel functional fermented dairy foods. The potential boosting effect was evaluated on four commercial mix cultures used to produce milk and soy fermented beverages. It was demonstrated that the booster effect took place, but it was variable and dependent not only on the mix culture used, but also on the substrate and A. platensis concentration. Also, rheological and color modifications were found to be dependent on these factors.

4.
Neuropsychologia ; 134: 107216, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31580880

RESUMO

In two ERP experiments, we examined the attention-related mechanism involved in perceiving infant emotions following exposure to security priming. Specifically, we examined how security priming affected securely and insecurely attached women. We found that both supraliminal and subliminal security priming resulted in increased attention allocation in anxiously and avoidantly attached women but had no effect on securely attached women. Moreover, we also found that supraliminal and subliminal security priming differed in their effectiveness in increasing attention allocation among anxiously and avoidantly attached women. Supraliminal security priming were more effective for anxiously attached women, whereas subliminal security priming were more effective for avoidantly attached women. The implications of these findings and directions for future research are discussed.


Assuntos
Atenção/fisiologia , Emoções/fisiologia , Apego ao Objeto , Estimulação Subliminar , Adulto , Ansiedade/psicologia , Povo Asiático , Cuidadores/psicologia , Sinais (Psicologia) , Eletroencefalografia , Potenciais Evocados/fisiologia , Expressão Facial , Feminino , Humanos , Lactente , Testes Neuropsicológicos , Adulto Jovem
5.
3 Biotech ; 8(9): 396, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30221109

RESUMO

Mutant forms of recombinant endoglucanase II (EG II, N194A), cellobiohydrolase I (CBH I, N45A) and cellobiohydrolase II (CBH II, N219A) from Penicillium verruculosum with enhanced cellulase activities, achieved by engineering of enzyme N-glycosylation sites in our previous studies, were used as components of the binary and ternary mixtures of cellulases in hydrolysis of Avicel and milled aspen wood. Using the engineered forms of the enzymes at a dosage of 10 mg/g substrate resulted in significant boosting of the glucose release from cellulose in the presence of excess ß-glucosidase relative to the performance of the corresponding wild-type mixtures at the same loading. The boosting effects reached 11-40% depending on the reaction time and substrate type. In hydrolysis of both cellulosic substrates by the binary mixtures of cellulases, all the enzyme pairs exhibited synergism. The magnitude of the synergistic effects (Ks) did not depend notably upon the induced mutations in the enzymes, and they were in the range of 1.3-1.8 for the combinations of EG II with CBH I (or CBH II), and 2.3-2.9 for the CBH I-CBH II pair. The results of this study should provide a basis for the development of a more effective fungal strain capable of producing cellulase cocktails with enhanced hydrolytic performance against lignocellulosic materials.

6.
Vet Immunol Immunopathol ; 178: 99-106, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27496748

RESUMO

Nasal delivery is a convenient and acceptable route for drug administration, and has been shown to elicit a much more potent local and systemic response compared with other drug delivery routes. We previously demonstrated that rectal administration of poly(lactide-co-glycolide)-encapsulated honeybee venom (P-HBV) could enhance systemic Th 1-specific immune responses. We therefore synthesized chitosan-coated P-HBV (CP-HBV) and then evaluated the immune-boosting efficacy of nasally administered CP-HBV on systemic and local intestinal immunity compared with non-chitosan-coated P-HBV. The nasally delivered CP-HBV effectively enhanced Th 1-specific responses, eliciting a significant increase in the CD3(+)CD4(+)CD8(-) Th cell population, lymphocyte proliferation capacity, and expression of Th 1 cytokines (IFN-γ, IL-12, and IL-2) in peripheral blood mononuclear cells. Furthermore, these immune-boosting effects persisted up to 21days post CP-HBV administration. Nasal administration of CP-HBV also led to an increase of not only the CD4(+) Th 1 and IFN-γ secreting CD4(+) Th 1 cell population but also Th 1-specific cytokines and transcription factors, including IL-12, IFN-γ, STAT4, and T-bet, in isolated mononuclear cells from the spleen and ileum.


Assuntos
Venenos de Abelha/administração & dosagem , Venenos de Abelha/imunologia , Abelhas/imunologia , Sus scrofa/imunologia , Administração Intranasal , Animais , Quitosana , Citocinas/genética , Citocinas/metabolismo , Sistemas de Liberação de Medicamentos , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Poliglactina 910 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sus scrofa/genética , Células Th1/imunologia , Fatores de Transcrição/genética , Regulação para Cima
7.
Front Pharmacol ; 7: 41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26973528

RESUMO

Cistanche species, known as Rou Cong-Rong in Chinese, are an endangered wild species and are mainly distributed in the arid lands and warm deserts of northwestern China. Within Traditional Chinese Medicine (TCM), Herba Cistanche is applied as a tonic and/or in a formula for chronic renal disease, impotence, female infertility, morbid leucorrhea, profuse metrorrhagia, and senile constipation. The chemical constituents of Herba Cistanche mainly consist of volatile oils, non-volatile phenylethanoid glycosides (PhGs), iridoids, lignans, alditols, oligosaccharides, and polysaccharides. There have been an increasing number of studies focusing on its bio-activities, including antioxidation, neuroprotection, and antiaging. The objective of this review is to introduce this herb to the world. Its taxonomy, distribution, and corresponding biological functions and molecular mechanisms are addressed in this review.

8.
J Med Food ; 18(1): 118-27, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25162916

RESUMO

This study assessed the effects of lemongrass (Cymbopogon citratus) tea on hematologic indices in human volunteers. One hundred five subjects (55 men and 50 women), aged 18 to 35 years, were randomly assigned to groups set to orally receive infusion prepared from 2, 4, or 8 g of C. citratus leaves once daily for 30 days. Assessment of hematologic indices (hemoglobin concentration [Hb], packed cell volume [PCV], red blood cell [RBC] count, mean cell Hb [MCH], mean cell volume [MCV], mean cell Hb concentration [MCHC], total white blood cell [WBC-total] and differentials, and platelets) were performed 1 day before (baseline), and at 10 (acute) and 30 days (subchronic phase) after the initiation of treatment. Results obtained on days 10 and 30 were compared with baseline values. Infusions prepared from C. citratus leaf powder, which tested positive for tannins, saponins, alkaloids, flavonoids, macro- and micronutrients, significantly increased PCV, Hb, and RBC (P<.05) in all subjects, particularly in the subchronic phase of the study. MCH, MCV, and MCHC were not significantly different from baseline values in both the sexes. WBCs and differentials significantly decreased (P<.05) with the exception of neutrophils and lymphocytes, which significantly increased in some or all groups (P<.05), respectively. C. citratus leaf infusion appears to exert an erythropoiesis boosting effect, likely due to some nutritional constituents and its antioxidant and pharmacologic properties.


Assuntos
Anemia/sangue , Cymbopogon/química , Eritropoese/efeitos dos fármacos , Hematínicos/farmacologia , Extratos Vegetais/farmacologia , Adolescente , Adulto , Anemia/tratamento farmacológico , Antioxidantes/farmacologia , Contagem de Eritrócitos , Índices de Eritrócitos , Eritrócitos/metabolismo , Feminino , Hematínicos/uso terapêutico , Hemoglobinas/metabolismo , Humanos , Leucócitos/metabolismo , Masculino , Fitoterapia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Adulto Jovem
9.
Vet Microbiol ; 170(3-4): 342-51, 2014 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-24679958

RESUMO

Diagnostic tests based on cell-mediated immunity are used in programmes for eradication of bovine tuberculosis (Mycobacterium bovis). Serological assays could be applied as ancillary methods to detect infected animals. Our objective was to evaluate two serological techniques: M. bovis Ab Test (IDEXX, USA) and Enferplex™ TB assay (Enfer, Ireland) in animals tested simultaneously with the single and comparative intradermal tests and the interferon-gamma assay. This work was performed at two stages. First, a preliminary panel of samples collected prior to intradermal tests from tuberculosis-free (n=60) and M. bovis-infected herds (n=78) was assayed, obtaining high specificity: 100% (M. bovis Ab Test) and 98.3% (Enferplex TB assay) but low sensitivity (detection of M. bovis infected animals): 23.9% (M. bovis Ab Test) and 32.6% (Enferplex TB assay). Subsequently, the use of serological techniques was further studied in two herds with M. bovis infection (n=77) using samples collected prior to, and 72 h and 15 days after PPD inoculation. The highest level of detection of infected animals for serology was achieved at 15 days post-intradermal tests taking advantage of the anamnestic effect: 70.4% and 85.2% in herd A, and 66.7% and 83.3% in herd B, using M. bovis Ab Test and Enferplex TB assay, respectively. Quantitative results (average values obtained with M. bovis Ab Test ELISA and degree of positivity obtained with Enferplex TB assay) were higher in animals showing lesions compatible with tuberculosis. No significant differences were observed in the number of confirmed infected animals detected with either serological technique.


Assuntos
Mycobacterium bovis/imunologia , Teste Tuberculínico/veterinária , Tuberculose Bovina/diagnóstico , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Interferon gama , Testes Intradérmicos/veterinária , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Teste Tuberculínico/normas , Tuberculose Bovina/imunologia , Tuberculose Bovina/patologia
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