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1.
PLoS One ; 19(5): e0303768, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758761

RESUMO

This research delves into the intricate interplay between perceived organizational support, proactive personality, and voice behavior. Furthermore, it establishes the pivotal role of work engagement as a mediating factor within the articulated research model. The study engaged 287 healthcare professionals within correctional institutions and detention centers in Indonesia, employing a dual-phase questionnaire distribution to capture the dynamic aspects of the participants' experiences. Utilizing the statistical technique of Partial Least Square-Structural Equation Modeling with the SmartPLS 4 program as an analysis tool, the collected data underwent comprehensive analysis. The outcomes reveal that proactive personality significantly influences voice behavior both directly and indirectly through its impact on work engagement. Conversely, perceived organizational support directly influences work engagement but does not exhibit a direct impact on voice behavior. These findings underscore the significance of proactive personality in fostering a conducive environment for constructive organizational change from a grassroots perspective. The study suggests that organizations prioritize the cultivation of proactive personality traits to stimulate voice behavior, thereby facilitating ongoing improvements and sustainable organizational progress.


Assuntos
Cultura Organizacional , Personalidade , Prisões , Humanos , Masculino , Feminino , Adulto , Inquéritos e Questionários , Indonésia , Pessoal de Saúde/psicologia , Engajamento no Trabalho
2.
J Food Sci ; 89(2): 1167-1186, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38193164

RESUMO

Reuterin is a natural antifungal agent derived from certain strains of Limosilactobacillus reuteri. Our previous study revealed that 6 mM reuterin inhibited completely the conidial germination of aflatoxigenic Aspergillus flavus. This study investigated the potential molecular mechanism of reuterin in inhibiting A. flavus conidial germination, which was pre-assumed that it correlated to the inhibition of some essential enzyme activity involved in conidial germination, specifically 1,3-ß-glucan synthase, chitin synthase, and catalases (catalase, bifunctional catalase-peroxidase, and spore-specific catalase). The complex of 1,3-ß-glucan synthase and chitin synthase with reuterin had a lower binding affinity than that with the substrate. Conversely, the complex of catalases with reuterin had a higher binding affinity than that with the substrate. It was suggested that 1,3-ß-glucan synthase and chitin synthase tended to bind the substrate rather than bind reuterin. In contrast, catalases tended to bind reuterin rather than bind the substrate. Therefore, reuterin could be a potential inhibitor of catalases but may not be an inhibitor of 1,3-ß-glucan synthase and chitin synthase. In this in silico study, we predicted that the potential molecular mechanism of reuterin in inhibiting A. flavus conidial germination was due to the inhibition of catalases activities by competitively binding to the enzymes active sites, thus resulting in the accumulation of reactive oxygen species in cells, leading to cells damage. PRACTICAL APPLICATION: This in silico study revealed that reuterin is a potential inhibitor of catalases in A. flavus, thereby interfering with the antioxidant system during conidial germination. This finding shows that reuterin can be used as an antifungal agent in food or agricultural products, inhibiting conidial germination completely.


Assuntos
Aspergillus flavus , Gliceraldeído/análogos & derivados , Propano , beta-Glucanas , Catalase/metabolismo , Esporos Fúngicos/metabolismo , Antifúngicos/química , Quitina Sintase/metabolismo
3.
Nutrients ; 15(21)2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37960342

RESUMO

Defects in mitochondrial fatty acid ß-oxidation (FAO) impair metabolic flexibility, which is an essential process for energy homeostasis. Very-long-chain acyl-CoA dehydrogenase (VLCADD; OMIM 609575) deficiency is the most common long-chain mitochondrial FAO disorder presenting with hypoglycemia as a common clinical manifestation. To prevent hypoglycemia, triheptanoin-a triglyceride composed of three heptanoates (C7) esterified with a glycerol backbone-can be used as a dietary treatment, since it is metabolized into precursors for gluconeogenesis. However, studies investigating the effect of triheptanoin on glucose homeostasis are limited. To understand the role of gluconeogenesis in the pathophysiology of long-chain mitochondrial FAO defects, we injected VLCAD-deficient (VLCAD-/-) mice with 13C3-glycerol in the presence and absence of heptanoate (C7). The incorporation of 13C3-glycerol into blood glucose was higher in VLCAD-/- mice than in WT mice, whereas the difference disappeared in the presence of C7. The result correlates with 13C enrichment of liver metabolites in VLCAD-/- mice. In contrast, the C7 bolus significantly decreased the 13C enrichment. These data suggest that the increased contribution of gluconeogenesis to the overall glucose production in VLCAD-/- mice increases the need for gluconeogenesis substrate, thereby avoiding hypoglycemia. Heptanoate is a suitable substrate to induce glucose production in mitochondrial FAO defect.


Assuntos
Hipoglicemia , Erros Inatos do Metabolismo Lipídico , Doenças Mitocondriais , Camundongos , Animais , Heptanoatos , Acil-CoA Desidrogenase de Cadeia Longa/genética , Acil-CoA Desidrogenase de Cadeia Longa/metabolismo , Glicerol , Ácidos Graxos/metabolismo , Glucose/uso terapêutico , Homeostase
4.
Food Technol Biotechnol ; 61(2): 226-237, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37457907

RESUMO

Research background: Lactic acid bacteria (LAB) are known to produce folate. However, this ability is highly strain-dependent. Folate synthesis in specific LAB strains is affected by the availability of folate, which can be consumed by other LAB under certain conditions. Moreover, differences in folate synthesis capabilities are related to the presence of folate biosynthesis-related genes and regulation of this pathway. Experimental approach: As basic information to better understand the regulation of folate biosynthesis among different LAB species and strains, folate biosynthetic genes were screened and identified in folate-producing and non-folate-producing LAB isolated from various local food sources in Indonesia. The extracellular folate productivity amounts of the isolates were analyzed using high-performance liquid chromatography with a diode array detector (HPLC-DAD). Results and conclusions: Eleven of the thirteen tested LAB isolates had all of the eight genes involved in folate biosynthesis (folE, folQ, folB, folK, folP, folC1, folA and folC2). Furthermore, these isolates produced extracellular folate ranging from 10.37 to 31.10 µg/mL. In contrast, two non-folate-producing isolates lacked several folate biosynthetic genes, such as folQ, folP and folA, which is possibly the reason for their inability to synthesize folate de novo. Phylogenetic tree construction revealed that the folate biosynthetic genes (excluding folK and folP) from six distinct species of folate-producing LAB isolates were monophyletic with homologous genes from other LAB species in the database. Novelty and scientific contribution: In this study, the distribution of folate biosynthetic genes in various LAB species was determined. The findings from this research support the use of folate biosynthesis marker genes in the genotypic screening for folate-producing LAB.

5.
Prev Nutr Food Sci ; 28(4): 386-400, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38188086

RESUMO

Folate (vitamin B9) is an essential nutrient for cell metabolism, especially in pregnant women; however, folate deficiency is a major global health issue. To address this issue, folate-rich fermented foods have been used as alternative sources of natural folate. Lactic acid bacteria (LAB), which are commonly involved in food fermentation, can synthesize and excrete folate into the medium, thereby increasing folate levels. However, screening for folate-producing LAB strains is necessary because this ability is highly dependent on the bacterial strain. Some strains of LAB consume folate, and their presence in a fermentation mix can lower the folate levels of the final product. Since microorganisms efficiently regulate folate biosynthesis to meet their growth needs, some strains of folate-producing LAB can deplete folate levels if folate is available in the media. Such folate-efficient producers possess a feedback inhibition mechanism that downregulates folate biosynthesis. Therefore, the application of folate-overproducing strains may be a key strategy for increasing folate levels in media with or without available folate. Many studies have been conducted to screen folate-producing bacteria, but very few have focused on the identification of overproducers. This is probably because of the limited understanding of the regulation of folate biosynthesis in LAB. In this review, we discuss the roles of folate-biosynthetic genes and their contributions to the ability of LAB to synthesize and regulate folate. In addition, we present various hypotheses regarding the regulation of the feedback inhibition mechanism of folate-biosynthetic enzymes and discuss strategies for obtaining folate-overproducing LAB strains.

6.
Food Sci Biotechnol ; 29(9): 1273-1279, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32802566

RESUMO

This research aimed to evaluate the effect of acid stress on the expression of stress regulator (grxB and rpoS) and virulence (ompA, hfq, and cpa) genes of Cronobacter sakazakii Yrt2a. The results showed that C. sakazakii Yrt2a experienced decrease in number during acid stress and was no longer culturable 90 min post exposure to pH 3.0. During acid stress, the expression of grxB, rpoS, ompA, cpa and hfq was upregulated by 2.15; 2.19; 1.55; 1.1 and 1.41 log, respectively. However, all genes expression was downregulated when the bacteria entered the unculturable state. The expression of gene grxB, rpoS, ompA, cpa decreased to 1.04; 0.37; 0.84 and 1.71 log, respectively; while hfq gene expression reached a level lower than that of control. This research implies a supposition that during acid stress, C. sakazakii was capable of maintaining its culturability and pathogenicity until they are no longer culturable.

7.
Front Vet Sci ; 7: 46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32118068

RESUMO

Broiler chickens are highly sensitive to high ambient temperatures due to their feathers, lack of skin sweat glands, and high productivity. Heat stress (HS) is a major concern for the poultry industry because it negatively affects growth as well as immune functions, which increase the potential risk of infectious disease outbreaks. Therefore, it is vital to elucidate HS's effect on the avian immune system, especially considering the global rise in average surface temperature. Our study identified a series of immunological disorders in heat-stressed broiler chickens. We exposed 22-day-old broiler chickens to a continuous HS condition (34.5 ± 0.5°C) for 14 days and immunized them with a prototype bovine serum albumin (BSA) antigen. The plasma and lymphoid tissues (thymus, bursa of Fabricius, and spleen) were harvested at the end of the experiments to investigate the induction of BSA-specific immune responses. Our results revealed that plasma titers of immunoglobulin (Ig)Y, IgM, and IgA antibodies specific for BSA were lower than those of thermoneutral chickens immunized with BSA. Furthermore, the spleens of the heat-stressed broiler chickens displayed severe depression of Bu1+ B cells and CD3+ T cells, including CD4+ T cells and CD8+ T cells, and lacked a fully developed germinal center (GC), which is crucial for B cell proliferation. These immunological abnormalities might be associated with severe depression of CD4-CD8- or CD4+CD8+ cells, which are precursors of either helper or killer T cells in the thymus and Bu1+ B cells in the bursa of Fabricius. Importantly, HS severely damaged the morphology of the thymic cortex and bursal follicles, where functional maturation of T and B cells occur. These results indicate that HS causes multiple immune abnormalities in broiler chickens by impairing the developmental process and functional maturation of T and B cells in both primary and secondary lymphoid tissues.

8.
Food Sci Biotechnol ; 27(3): 915-920, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30263819

RESUMO

Cronobacter spp. in powdered infant formula has been etiologically linked to meningitis and necrotizing enterocolitis in certain groups of infants. This study aimed to determine whether C. sakazakii Yrt2a strain experiencing desiccation stress could enter viable but nonculturable (VBNC) state as well as to examine the expression of genes associated with stress and virulence during the above states. Stress and VBNC conditions were determined based on viability and culturability assays. Expression of genes related to stress (rpoS) and virulence (hfq and ompA) was evaluated by real-time PCR. The results showed that C. sakazakii Yrt2a entered VBNC 24 days post exposure to 2 h of desiccation treatment. The expression of rpoS, hfq and ompA genes was up-regulated during stress conditions, suggesting that Cronobacter successfully managed stress to maintain its culturability while maintaining its virulence. The expression of the target genes decreased at VBNC state but remained higher than that of a normal state. These findings reinforce the assumption that C. sakazakii undergoing VBNC state maintains its pathogenicity.

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