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The global emergency caused by the novel coronavirus (COVID-19) pandemic has impacted access to goods and services such as health care and social supports, but the impact on infant feeding remains unclear. Thus, the objective of this study was to explore how caregivers of infants under 6 months of age perceived changes to infant feeding and other food and health-related matters during the COVID-19 State of Emergency in Nova Scotia, Canada. Four weeks after the State of Emergency began, between 17 April and 15 May 2020, caregivers completed this online survey, including the Perceived Stress Scale. Participants (n = 335) were 99% female and mostly White (87%). Over half (60%) were breastfeeding, and 71% had a household income over CAD$60,000. Most participants (77%) received governmental parental benefits before the emergency, and 59% experienced no COVID-19-related economic changes. Over three quarters of participants (77%) scored moderate levels of perceived stress. Common themes of concern included social isolation, COVID-19 infection (both caregiver and infant), and a lack of access to goods, namely, human milk substitutes ('infant formula'), and services, including health care, lactation support, and social supports. Most COVID-19-related information was sought from the internet and social media, so for broad reach, future evidence-based information should be shared via online platforms. Although participants were experiencing moderate self-perceived stress and shared numerous concerns, very few COVID-19-related changes to infant feeding were reported, and there were few differences by socio-economic status, likely due to a strong economic safety net in this Canadian setting.
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Aleitamento Materno , COVID-19 , Cuidadores/psicologia , Saúde Mental/estatística & dados numéricos , Estresse Psicológico , Adulto , Ansiedade , Criança , Feminino , Humanos , Lactente , Masculino , Nova Escócia/epidemiologia , Gravidez , SARS-CoV-2 , Isolamento SocialRESUMO
BACKGROUND: Contamination of food or the environment by fungi, especially those resistant to conventional fungicides or drugs, represents a hazard to human health. The objective of this study is to identify safe, natural antifungal agents that can remove fungal pathogens or contaminants rapidly from food and / or environmental sources. RESULTS: Fifteen antifungal compounds (nine benzo derivatives as candidates; six conventional fungicides as references) were investigated. Three benzo analogs, namely octyl gallate (OG), trans-cinnamaldehyde (CA), and 2-hydroxy-5-methoxybenzaldehyde (2H5M), at 1 g L-1 (3.54 mmol), 1 mL L-1 (7.21 mmol), 1 mL L-1 (5.39 mmol), respectively, achieved ≥99.9% fungal death after 0.5, 2.5 or 24 h of treatments, respectively, in in vitro phosphate-buffered saline (PBS) bioassay. However, when OG, CA, and 2H5M were examined in commercial food matrices, organic apple, or grape juices, only CA maintained a similar level of antifungal activity, compared with a PBS bioassay. trans-Cinnamaldehyde showed higher antifungal activity at pH 3.5, equivalent to that of commercial fruit juices, than at pH 5.6. In soil sample tests, the application of 1 mL L-1 (7.21 mmol) CA to conventional maize / tomato soil samples (pH 6.8) for 2.5 h resulted in ≥99.9% fungal death, indicating CA could also eliminate fungal contaminants in soil. While the conventional fungicide thiabendazole exerted antifungal activity comparable to CA, thiabendazole enhanced the production of carcinogenic aflatoxins by Aspergillus flavus, an undesirable side effect. CONCLUSION: trans-Cinnamaldehyde could be developed as a potent antifungal agent in food processing or soil sanitation by reducing the time / cost necessary for fungal removal. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.
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Microbiologia de Alimentos , Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Microbiologia do Solo , Acroleína/análogos & derivados , Acroleína/farmacologia , Aflatoxinas/biossíntese , Aspergillus flavus/efeitos dos fármacos , Aspergillus flavus/metabolismo , Benzaldeídos/farmacologia , Contaminação de Alimentos , Sucos de Frutas e Vegetais/microbiologia , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacologia , Concentração de Íons de HidrogênioRESUMO
Exclusive breastfeeding to 6 months with continued breastfeeding up to 2 years and beyond are well-established infant feeding recommendations based on evidence that breastfeeding has unparalleled maternal and infant health benefits as well as environmental and economic benefits. As with many high-income countries, breastfeeding rates remain suboptimal with only a quarter of Canadian and European infants receiving breast milk exclusively for the first 6 months. Breastfeeding promotion efforts have largely targeted caregivers in the prenatal and postnatal period; however, breastfeeding outcomes have been shown to be associated with broader sociocultural factors. Noncaregivers play an influential role in infant feeding at both an individual level (e.g., cues and input from health care practitioners and caregivers' social networks; as future parents) as well as a broader population level (sociocultural norms and policy decisions). This paper outlines recent research on breastfeeding knowledge and attitudes of noncaregivers by population subgroup. Positive correlations have been identified between breastfeeding attitudes, infant feeding knowledge, breastfeeding exposure, and breastfeeding intention among different subgroups; however, key knowledge gaps, lack of exposure to breastfeeding, and negative public perceptions of breastfeeding persist. Dietitians can advocate for breastfeeding promotion strategies that consider the role of noncaregivers to address sociocultural norms around breastfeeding.
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Aleitamento Materno/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Opinião Pública , Adolescente , Adulto , Fatores Etários , Idoso , Canadá , Criança , Cultura , Feminino , Educação em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Estudantes , Universidades , Adulto JovemRESUMO
In Canada, adherence to the national 'Nutrition for Healthy Term Infants' recommendations of infant and young child feeding (IYCF; 0-24 months) is suboptimal. While maternal knowledge of IYCF is commonly assessed, that of the general public has rarely been explored. Our objective was to assess the knowledge of, and confidence in answers to, Canadian IYCF recommendations among a diverse sample of adults in Nova Scotia, Canada. Between March and May 2018, a self-administered questionnaire examining IYCF knowledge, self-rated confidence, and sociodemographic information was conducted among Nova Scotians (≥19 years) in public locations. We surveyed 229 adults; 60% (n=134) were women. Mean (95% CI) age was 44 (41,46) years, 73% self-identified as white, 77% were born in Canada, and 69% were parents. Knowledge deficits were: age to terminate breastfeeding (18.3 (16.7,19.9) months; recommendation: ≥24 months), age to introduce solids (9.2 (8.2,10.2) months; recommendation: 6 months), vitamin D supplementation (10% correct), and optimal complementary foods (only 37% indicated iron-rich foods). Correct IYCF knowledge was lower among men, non-parents, young adults (19-29 years) and low-income adults (<$50,000/year). Mean self-rated confidence (out of 10) was high (7.2 (6.9,7.5)), and not different (p>0.05) between correct and incorrect responses for: best food for a newborn, age to terminate any breastfeeding, and age to start family meal foods. We found low knowledge of IYCF guidelines, yet high confidence in responses regardless of accuracy, among adults in Nova Scotia. General public knowledge deficits may contribute to an unsupportive culture around IYCF practices and low adherence to current recommendations.
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Aleitamento Materno/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Alimentos Infantis/estatística & dados numéricos , Fenômenos Fisiológicos da Nutrição do Lactente , Recomendações Nutricionais , Adulto , Estudos Transversais , Suplementos Nutricionais , Feminino , Humanos , Lactente , Masculino , Nova Escócia , Fatores Sexuais , Fatores Socioeconômicos , Inquéritos e Questionários , Vitamina D/administração & dosagemRESUMO
A new family of materials comprised of cellulose, cellulose nanomaterials (CNMs), having properties and functionalities distinct from molecular cellulose and wood pulp, is being developed for applications that were once thought impossible for cellulosic materials. Commercialization, paralleled by research in this field, is fueled by the unique combination of characteristics, such as high on-axis stiffness, sustainability, scalability, and mechanical reinforcement of a wide variety of materials, leading to their utility across a broad spectrum of high-performance material applications. However, with this exponential growth in interest/activity, the development of measurement protocols necessary for consistent, reliable and accurate materials characterization has been outpaced. These protocols, developed in the broader research community, are critical for the advancement in understanding, process optimization, and utilization of CNMs in materials development. This review establishes detailed best practices, methods and techniques for characterizing CNM particle morphology, surface chemistry, surface charge, purity, crystallinity, rheological properties, mechanical properties, and toxicity for two distinct forms of CNMs: cellulose nanocrystals and cellulose nanofibrils.
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Disruption of fungal cell wall should be an effective intervention strategy. However, the cell wall-disrupting echinocandin drugs, such as caspofungin (CAS), cannot exterminate filamentous fungal pathogens during treatment. For potency improvement of cell wall-disrupting agents (CAS, octyl gallate (OG)), antifungal efficacy of thirty-three cinnamic acid derivatives was investigated against Saccharomyces cerevisiaeslt2Δ, bck1Δ, mutants of the mitogen-activated protein kinase (MAPK), and MAPK kinase kinase, respectively, in cell wall integrity system, and glr1Δ, mutant of CAS-responsive glutathione reductase. Cell wall mutants were highly susceptible to four cinnamic acids (4-chloro-α-methyl-, 4-methoxy-, 4-methyl-, 3-methylcinnamic acids), where 4-chloro-α-methyl- and 4-methylcinnamic acids possessed the highest activity. Structure-activity relationship revealed that 4-methylcinnamic acid, the deoxygenated structure of 4-methoxycinnamic acid, overcame tolerance of glr1Δ to 4-methoxycinnamic acid, indicating the significance of para substitution of methyl moiety for effective fungal control. The potential of compounds as chemosensitizers (intervention catalysts) to cell wall disruptants (viz., 4-chloro-α-methyl- or 4-methylcinnamic acids + CAS or OG) was assessed according to Clinical Laboratory Standards Institute M38-A. Synergistic chemosensitization greatly lowers minimum inhibitory concentrations of the co-administered drug/agents. 4-Chloro-α-methylcinnamic acid further overcame fludioxonil tolerance of Aspergillus fumigatus antioxidant MAPK mutants (sakAΔ, mpkCΔ). Collectively, 4-chloro-α-methyl- and 4-methylcinnamic acids possess chemosensitizing capability to augment antifungal efficacy of conventional drug/agents, thus could be developed as target-based (i.e., cell wall disruption) intervention catalysts.
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Antifúngicos/farmacologia , Parede Celular/efeitos dos fármacos , Cinamatos/farmacologia , Fungos/efeitos dos fármacos , Antifúngicos/química , Caspofungina , Parede Celular/química , Cinamatos/química , Dioxóis/farmacologia , Tolerância a Medicamentos/genética , Equinocandinas/química , Fungos/patogenicidade , Lipopeptídeos/química , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutação , Pirróis/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Relação Estrutura-AtividadeRESUMO
Disruption of cell wall integrity system should be an effective strategy for control of fungal pathogens. To augment the cell wall disruption efficacy of monoterpenoid phenols (carvacrol, thymol), antimycotic potency of benzaldehyde derivatives that can serve as chemosensitizing agents were evaluated against strains of Saccharomyces cerevisiae wild type (WT), slt2Δ and bck1Δ (mutants of the mitogen-activated protein kinase (MAPK) and MAPK kinase kinase, respectively, in the cell wall integrity pathway). Among fourteen compounds investigated, slt2Δ and bck1Δ showed higher susceptibility to nine benzaldehydes, compared to WT. Differential antimycotic activity of screened compounds indicated "structure-activity relationship" for targeting the cell wall integrity, where 2-hydroxy-4-methoxybenzaldehyde (2H4M) exhibited the highest antimycotic potency. The efficacy of 2H4M as an effective chemosensitizer to monoterpenoid phenols (viz., 2H4M + carvacrol or thymol) was assessed in yeasts or filamentous fungi (Aspergillus, Penicillium) according to European Committee on Antimicrobial Susceptibility Testing or Clinical Laboratory Standards Institute M38-A protocols, respectively. Synergistic chemosensitization greatly lowers minimum inhibitory or fungicidal concentrations of the co-administered compounds. 2H4M also overcame the tolerance of two MAPK mutants (sakAΔ, mpkCΔ) of Aspergillus fumigatus to fludioxonil (phenylpyrrole fungicide). Collectively, 2H4M possesses chemosensitizing capability to magnify the efficacy of monoterpenoid phenols, which improves target-based (viz., cell wall disruption) antifungal intervention.
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Antifúngicos/farmacologia , Benzaldeídos/farmacologia , Parede Celular/efeitos dos fármacos , Monoterpenos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Timol/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/enzimologia , Aspergillus fumigatus/genética , Parede Celular/enzimologia , Parede Celular/genética , Cimenos , Dioxóis/farmacologia , Sinergismo Farmacológico , Expressão Gênica , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Testes de Sensibilidade Microbiana , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Penicillium/efeitos dos fármacos , Penicillium/enzimologia , Penicillium/genética , Pirróis/farmacologia , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Relação Estrutura-AtividadeRESUMO
Oxidative treatment is one of the strategies for preventing Penicillium contamination in crops/foods. The antifungal efficacy of hydrogen peroxide (H2O2; oxidant) was investigated in Penicillium strains by using kojic acid (KA) as a chemosensitizing agent, which can enhance the susceptibility of pathogens to antifungal agents. Co-application of KA with H2O2 (chemosensitization) resulted in the enhancement of antifungal activity of either compound, when compared to the independent application of each agent alone. Of note, heat enhanced the activity of H2O2 to a greater extent during chemosensitization, whereby the minimum inhibitory or minimum fungicidal concentrations of H2O2 was decreased up to 4 or 13 fold, respectively, at 35-45 °C (heat), when compared to that at 28 °C (normal growth temperature). However, heat didn't increase the antifungal activity of KA, indicating specificity exists between heat and types of antifungals applied. The effect of chemosensitization was also strain-specific, where P. expansum (both parental and fludioxonil-resistant mutants) or P. italicum 983 exhibited relatively higher susceptibility to the chemosensitization, comparing to other Penicillium strains tested. Collectively, chemosensitization can serve as a potent antifungal strategy to lower effective dosages of toxic antifungal substances, such as H2O2. This can lead to coincidental lowering of environmental and health risks.
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Antifúngicos/farmacologia , Antioxidantes/farmacologia , Peróxido de Hidrogênio/farmacologia , Oxidantes/farmacologia , Penicillium/crescimento & desenvolvimento , Pironas/farmacologiaRESUMO
Co-application of certain types of compounds to conventional antimicrobial drugs can enhance the efficacy of the drugs through a process termed chemosensitization. We show that kojic acid (KA), a natural pyrone, is a potent chemosensitizing agent of complex III inhibitors disrupting the mitochondrial respiratory chain in fungi. Addition of KA greatly lowered the minimum inhibitory concentrations of complex III inhibitors tested against certain filamentous fungi. Efficacy of KA synergism in decreasing order was pyraclostrobin > kresoxim-methyl > antimycin A. KA was also found to be a chemosensitizer of cells to hydrogen peroxide (H2O2), tested as a mimic of reactive oxygen species involved in host defense during infection, against several human fungal pathogens and Penicillium strains infecting crops. In comparison, KA-mediated chemosensitization to complex III inhibitors/H2O2 was undetectable in other types of fungi, including Aspergillus flavus, A. parasiticus, and P. griseofulvum, among others. Of note, KA was found to function as an antioxidant, but not as an antifungal chemosensitizer in yeasts. In summary, KA could serve as an antifungal chemosensitizer to complex III inhibitors or H2O2 against selected human pathogens or Penicillium species. KA-mediated chemosensitization to H2O2 seemed specific for filamentous fungi. Thus, results indicate strain- and/or drug-specificity exist during KA chemosensitization.
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Antifúngicos/farmacologia , Mitocôndrias/efeitos dos fármacos , Pironas/farmacologia , Aerobiose/efeitos dos fármacos , Antifúngicos/química , Antimicina A/química , Antimicina A/farmacologia , Antioxidantes/farmacologia , Bioensaio , Carbamatos/química , Carbamatos/farmacologia , Respiração Celular/efeitos dos fármacos , Sinergismo Farmacológico , Complexo III da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Fungos/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Metacrilatos/química , Metacrilatos/farmacologia , Testes de Sensibilidade Microbiana , Mitocôndrias/metabolismo , Mutação/genética , Fenilacetatos/química , Fenilacetatos/farmacologia , Pirazóis/química , Pirazóis/farmacologia , Pironas/química , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , EstrobilurinasRESUMO
Enhanced control of species of Cryptococcus, non-fermentative yeast pathogens, was achieved by chemosensitization through co-application of certain compounds with a conventional antimicrobial drug. The species of Cryptococcus tested showed higher sensitivity to mitochondrial respiratory chain (MRC) inhibition compared to species of Candida. This higher sensitivity results from the inability of Cryptococcus to generate cellular energy through fermentation. To heighten disruption of cellular MRC, octyl gallate (OG) or 2,3-dihydroxybenzaldehyde (2,3-DHBA), phenolic compounds inhibiting mitochondrial functions, were selected as chemosensitizers to pyraclostrobin (PCS; an inhibitor of complex III of MRC). The cryptococci were more susceptible to the chemosensitization (i.e., PCS + OG or 2,3-DHBA) than the Candida with all Cryptococcus strains tested being sensitive to this chemosensitization. Alternatively, only few of the Candida strains showed sensitivity. OG possessed higher chemosensitizing potency than 2,3-DHBA, where the concentration of OG required with the drug to achieve chemosensitizing synergism was much lower than that required of 2,3-DHBA. Bioassays with gene deletion mutants of the model yeast Saccharomyces cerevisiae showed that OG or 2,3-DHBA affect different cellular targets. These assays revealed mitochondrial superoxide dismutase or glutathione homeostasis plays a relatively greater role in fungal tolerance to 2,3-DHBA or OG, respectively. These findings show that application of chemosensitizing compounds that augment MRC debilitation is a promising strategy to antifungal control against yeast pathogens.
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Antifúngicos/farmacologia , Candida/patogenicidade , Cryptococcus/efeitos dos fármacos , Mitocôndrias/metabolismo , Benzaldeídos/farmacologia , Candida/crescimento & desenvolvimento , Candida/metabolismo , Catecóis/farmacologia , Transporte de Elétrons/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fermentação , Testes de Sensibilidade Microbiana , Fenóis/metabolismoRESUMO
Control of food-contaminating fungi, especially pathogens that produce mycotoxins, is problematic since effective method for intervening fungal infection on food crops is often limited. Generally Regarded As Safe (GRAS) chemicals, such as natural compounds or their structural derivatives, can be developed as antimicrobial agents for sustainable food/crop production. This study identified that long-chain alkyl gallates, i.e., octyl-, nonyl-, and decyl gallates (OG (octyl 3,4,5-trihydroxybenzoic acid), NG, DG), can function as heat-sensitizing agents that effectively prevent fungal contamination. Out of twenty-eight candidate compounds and six conventional antifungal agents examined, the heat-sensitizing capacity was unique to the long-chain alkyl gallates, where OG exhibited the highest activity, followed by DG and NG. Since OG is a GRAS compound classified by the United States Food and Drug Administration (FDA), further in vitro antifungal studies were performed using OG. When OG and mild heat (57.5°C) were co-administered for 90 seconds, the treatment achieved > 99.999% fungal death (> 5 log reduction). Application of either treatment alone was significantly less effective at reducing fungal survival. Of note, co-application of OG (3 mM) and mild heat (50°C) for 20 minutes completely prevented the survival of aflatoxigenic Aspergillus flavus contaminating crop seeds (Brassica rapa Pekinensis), while seed germination rate was unaffected. Heat-sensitization was also determined in selected bacterial strains (Escherichia coli, Agrobacterium tumefaciens). Altogether, OG is an effective heat-sensitizing agent for control of microbial pathogens. OG-mediated heat sensitization will improve the efficacy of antimicrobial practices, achieving safe, rapid, and cost-effective pathogen control in agriculture/food industry settings.
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Human milk is the ideal source of nutrition for infants; however, adherence to breastfeeding recommendations is suboptimal and availability of Canadian breastfeeding data are limited. Using the 2017-2018 Canadian Community Health Survey Public Use Microdata File (Maternal Experiences Module, n = 5558, weighted n = 1 669 462) we computed breastfeeding indicators and explored sociodemographic, health, and geographical predictors of breastfeeding with univariate logistic regression models. Nationally, of all participants who gave birth in the preceding 5 years, 91% initiated breastfeeding, 43% exclusively breastfed to ≥5 months and 35% to ≥6 months, 56% reported any breastfeeding at ≥6 months, and 31% reported breastfeeding at ≥12 months. Breastfeeding cessation was most commonly attributed to insufficient milk supply (25%), but reasons differed significantly by breastfeeding duration. Breastfeeding initiation, exclusivity for ≥5 months, and extended breastfeeding ≥12 months all differed by geographic region, and by most sociodemographic and health characteristics. Positive breastfeeding outcomes were highest in British Columbia, and lowest in Quebec and the Atlantic region, and generally higher if caregivers had recently immigrated to Canada, were married, were >30 years of age, were not White, were nonsmoking, had completed postsecondary education, and had an annual household income >$40 000. These disparities indicate the need for tailored, equitable approaches to breastfeeding support, and continued regional monitoring of breastfeeding outcomes.
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Aleitamento Materno , Saúde Pública , Lactente , Feminino , Humanos , Inquéritos e Questionários , Inquéritos Epidemiológicos , Colúmbia BritânicaRESUMO
Background: Preoperative patient evaluation and optimization in a preoperative evaluation center (PEC) has been shown to improve operating room (OR) efficiency and patient care. However, performing preoperative evaluation on all patients scheduled for surgery or procedure would be time- and resource-consuming. Therefore, appropriate patient selection for evaluation at PECs is one aspect of improving PEC efficiency. In this study, we evaluate the effect of an enhanced preoperative evaluation process (PEP), utilizing a nursing triage phone call and information technology (IT) optimizations, on PEC efficiency and the quality of care in bariatric surgery patients. We hypothesized that, compared to a traditional PEP, the enhanced PEP would improve PEC efficiency without a negative impact on quality. Methods: The study was a retrospective cohort analysis of 1550 patients from January 2014 to March 2017 at a large, tertiary care academic health system. The study was a before/after comparison that compared the enhanced PEP model to the traditional PEP model. The primary outcome was the efficiency of the PEC, which was measured by the reduction of in-person patient visits at the PEC. The secondary outcome was the quality of care, which was measured by delays, cancellations, and the need for additional testing on the day of surgery (DOS). Results: The enhanced PEP improved the primary outcome of efficiency, as evident by an 80% decrease in in-person patient visits to the PEC. There was no reduction in the secondary outcome of the quality of care as measured by delays, cancellations, or the need for additional testing on the DOS. The implementation of the enhanced PEP did not result in increased costs or resource utilization. Conclusions: The enhanced PEP in a multi-disciplinary preoperative process can improve the efficiency of PEC for bariatric surgery patients without any decrease in the quality of care. The enhanced PEP process can be implemented without an increase in resource utilization and can be particularly useful during the COVID-19 pandemic.
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The United States is a principal producer of tree nuts (almonds, pistachios, and walnuts), resulting in the generation of excess of tree-nutshell by-products each year, with few market outlets. A nutshell is an essential, lignocellulosic layer that protects a kernel (seed) from the environment during cultivation. The objective of this study was to develop nutshell by-products as herbicide delivery systems, which would not only enable sustainable weed control in fields but also increases nutshell value and reduce the cost of waste disposal. We recently identified a natural salicylaldehyde (SA) that emits volatiles with both herbicidal and antifungal properties. In this study, walnut shell particles saturated with 0.8 to 1.6 M SA were developed as delivery vehicles for SA to soil, which allowed for the controlled release of an SA fumigant for weed control. The pre- and post-emergent herbicidal efficacy of SA was investigated using model monocot (Lolium arundinaceum (Schreb.) Darbysh; turfgrass) and dicot (Brassica rapa var. pekinensis; Chinese cabbage) plants. We compared (1) the effects of different types of solvents for dissolving SA (dimethyl sulfoxide (DMSO) and ethanol (60%, v/v)), and (2) the effect of covering soil with plastic layers (i.e., soil pasteurization) or not covering soil during SA fumigation using nutshells. Results: In the pre-emergent herbicidal testing with the soil covered, the dicot plants exhibited levels of higher susceptibility to SA in DMSO emitted from nutshells when compared to the monocot plants. The seed germination frequencies in the dicots were 15% and 1% with 0.8 and 1.6 M SA, respectively, while those in the monocots were 32% and 18%, respectively, under the same test conditions. In the post-emergent herbicidal testing with the soil covered, the growth of both the monocot and dicot plants was completely prevented after 5 to 7 days of SA fumigation, resulting in the deaths of entire plants. It was noteworthy that in the post-emergent herbicidal testing, SA dissolved in ethanol (60%, v/v) completely disrupted the growth of the monocot and dicot plants as early as 3 days after SA emission from the nutshells, even without the soil being covered. Tree-nutshell particles could serve as effective SA delivery vehicles with controlled release capabilities for SA. The SA exhibited pre- and post-emergent herbicidal activities against the monocot and dicot plants at most growth stages. SA (0.8 and 1.6 M) dissolved in ethanol (60%, v/v) might exert a synergism for higher herbicidal activity after emission from nutshells. Since tree nuts capture/store a substantial amount of carbon over their life-cycles, the new and sustainable utility of using nutshells not only reduces carbon emissions but also valorizes tree-nut by-products, thus benefitting the tree-nut industry.
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Natural compounds that pose no significant medical or environmental side effects are potential sources of antifungal agents, either in their nascent form or as structural backbones for more effective derivatives. Kojic acid (KA) is one such compound. It is a natural by-product of fungal fermentation commonly employed by food and cosmetic industries. We show that KA greatly lowers minimum inhibitory (MIC) or fungicidal (MFC) concentrations of commercial medicinal and agricultural antifungal agents, amphotericin B (AMB) and strobilurin, respectively, against pathogenic yeasts and filamentous fungi. Assays using two mitogen-activated protein kinase (MAPK) mutants, i.e., sakA∆, mpkC∆, of Aspergillus fumigatus, an agent for human invasive aspergillosis, with hydrogen peroxide (H(2)O(2)) or AMB indicate such chemosensitizing activity of KA is most conceivably through disruption of fungal antioxidation systems. KA could be developed as a chemosensitizer to enhance efficacy of certain conventional antifungal drugs or fungicides.
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Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Pironas/farmacologia , Antifúngicos/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Sinergismo Farmacológico , Humanos , Peróxido de Hidrogênio/farmacologia , Testes de Sensibilidade Microbiana , Pironas/química , Leveduras/efeitos dos fármacosRESUMO
BACKGROUND: Social norms and public perception of breastfeeding are well-established predictors of breastfeeding outcomes; however, little is known about perceptions of breastfeeding beyond infancy or public breastfeeding among the public in Nova Scotia, Canada. RESEARCH AIM: To explore public opinion about breastfeeding beyond infancy and public breastfeeding. METHODS: In this cross-sectional study participants were recruited from public spaces in Nova Scotia, Canada. Using photo elicitation methods, participants (N = 229) viewed six photographs of breastfeeding children aged 2 weeks, 13 months, and 2.5 years, one photograph captured at home, and the other in a public space (a café, a store, or outdoors). Participants were asked to score their self-rated comfort with each photograph on a 10.0 cm visual analog scale and asked to share their feelings about each photograph (open-ended responses). RESULTS: Mean (SD) visual analog scale comfort scores for photographs differed by location (private, 7.9 [2.2]; public, 7.3 [2.6]; p < .05) and child age (2 weeks, 8.5 [2.0]; 13 months, 7.5 [2.6]; 2.5 years, 6.9 [3.0]; p < .05). Participants who identified as women and parents self-reported significantly higher comfort with all photographs, while younger participants and urban dwellers were generally less comfortable. Open-ended responses varied considerably, but a higher proportion of negative comments were reported for older children feeding in public spaces (e.g., 2.5-year-old in public: "Inappropriate. Indecent. Abnormal."). CONCLUSION: Given the importance of social norms in supporting breastfeeding, future public health campaigns should strive to normalize breastfeeding beyond infancy, and in public spaces.
Assuntos
Aleitamento Materno , Opinião Pública , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Nova Escócia , PaisRESUMO
BACKGROUND: Disruption of cellular antioxidation systems should be an effective method for control of fungal pathogens. Such disruption can be achieved with redox-active compounds. Natural phenolic compounds can serve as potent redox cyclers that inhibit microbial growth through destabilization of cellular redox homeostasis and/or antioxidation systems. The aim of this study was to identify benzaldehydes that disrupt the fungal antioxidation system. These compounds could then function as chemosensitizing agents in concert with conventional drugs or fungicides to improve antifungal efficacy. METHODS: Benzaldehydes were tested as natural antifungal agents against strains of Aspergillus fumigatus, A. flavus, A. terreus and Penicillium expansum, fungi that are causative agents of human invasive aspergillosis and/or are mycotoxigenic. The yeast Saccharomyces cerevisiae was also used as a model system for identifying gene targets of benzaldehydes. The efficacy of screened compounds as effective chemosensitizers or as antifungal agents in formulations was tested with methods outlined by the Clinical Laboratory Standards Institute (CLSI). RESULTS: Several benzaldehydes are identified having potent antifungal activity. Structure-activity analysis reveals that antifungal activity increases by the presence of an ortho-hydroxyl group in the aromatic ring. Use of deletion mutants in the oxidative stress-response pathway of S. cerevisiae (sod1Δ, sod2Δ, glr1Δ) and two mitogen-activated protein kinase (MAPK) mutants of A. fumigatus (sakAΔ, mpkCΔ), indicates antifungal activity of the benzaldehydes is through disruption of cellular antioxidation. Certain benzaldehydes, in combination with phenylpyrroles, overcome tolerance of A. fumigatus MAPK mutants to this agent and/or increase sensitivity of fungal pathogens to mitochondrial respiration inhibitory agents. Synergistic chemosensitization greatly lowers minimum inhibitory (MIC) or fungicidal (MFC) concentrations. Effective inhibition of fungal growth can also be achieved using combinations of these benzaldehydes. CONCLUSIONS: Natural benzaldehydes targeting cellular antioxidation components of fungi, such as superoxide dismutases, glutathione reductase, etc., effectively inhibit fungal growth. They possess antifungal or chemosensitizing capacity to enhance efficacy of conventional antifungal agents. Chemosensitization can reduce costs, abate resistance, and alleviate negative side effects associated with current antifungal treatments.
Assuntos
Antifúngicos/farmacologia , Antioxidantes/farmacologia , Benzaldeídos/farmacologia , Fungos/efeitos dos fármacos , Micoses/microbiologia , Antifúngicos/química , Antioxidantes/química , Benzaldeídos/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungos/genética , Fungos/isolamento & purificação , Fungos/metabolismo , Humanos , Oxirredução/efeitos dos fármacos , Relação Estrutura-Atividade , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismoRESUMO
Various species of fungi in the genus Aspergillus are the most common causative agents of invasive aspergillosis and/or producers of hepato-carcinogenic mycotoxins. Salicylaldehyde (SA), a volatile natural compound, exhibited potent antifungal and anti-mycotoxigenic activities to A. flavus and A. parasiticus. By exposure to the volatilized SA, the growth of A. parasiticus was inhibited up to 10-75% at 9.5 mM ≤ SA ≤ 16.0 mM, while complete growth inhibition was achieved at 19.0 mM ≤ SA. Similar trends were also observed with A. flavus. The aflatoxin production, i.e., aflatoxin B(1) and B(2) (AFB(1), AFB(2)) for A. flavus and AFB(1), AFB(2), AFG(1), and AFG(2) for A. parasiticus, in the SA-treated (9.5 mM) fungi was reduced by ~13-45% compared with the untreated control. Using gene deletion mutants of the model yeast Saccharomyces cerevisiae, we identified the fungal antioxidation system as the molecular target of SA, where sod1Δ [cytosolic superoxide dismutase (SOD)], sod2Δ (mitochondrial SOD), and glr1Δ (glutathione reductase) mutants showed increased sensitivity to this compound. Also sensitive was the gene deletion mutant, vph2Δ, for the vacuolar ATPase assembly protein, suggesting vacuolar detoxification plays an important role for fungal tolerance to SA. In chemosensitization experiments, co-application of SA with either antimycin A or strobilurin (inhibitors of mitochondrial respiration) resulted in complete growth inhibition of Aspergillus at much lower dose treatment of either agent, alone. Therefore, SA can enhance antifungal activity of commercial antifungal agents required to achieve effective control. SA is a potent antifungal and anti-aflatoxigenic volatile that may have some practical application as a fumigant.
Assuntos
Aldeídos/farmacologia , Antifúngicos/farmacologia , Antimicina A/farmacologia , Aspergillus/efeitos dos fármacos , Micotoxinas/antagonistas & inibidores , Antioxidantes/metabolismo , Aspergillus/crescimento & desenvolvimento , Ácidos Graxos Insaturados/farmacologia , Deleção de Genes , Metacrilatos/farmacologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , EstrobilurinasRESUMO
The fungal antioxidant system is one of the targets of the redox-active polyene antifungal drugs, including amphotericin B (AMB), nystatin (NYS), and natamycin (NAT). Besides medical applications, NAT has been used in industry for preserving foods and crops. In this study, we investigated two parameters (pH and food ingredients) affecting NAT efficacy. In the human pathogen, Aspergillus fumigatus, NAT (2 to 16 µg mL-1) exerted higher activity at pH 5.6 than at pH 3.5 on a defined medium. In contrast, NAT exhibited higher activity at pH 3.5 than at pH 5.6 against foodborne fungal contaminants, Aspergillus flavus, Aspergillus parasiticus, and Penicillium expansum, with P. expansum being the most sensitive. In commercial food matrices (10 organic fruit juices), food ingredients differentially affected NAT antifungal efficacy. Noteworthily, NAT overcame tolerance of the A. fumigatus signaling mutants to the fungicide fludioxonil and exerted antifungal synergism with the secondary metabolite, kojic acid (KA). Altogether, NAT exhibited better antifungal activity at acidic pH against foodborne fungi; however, the ingredients from commercial food matrices presented greater impact on NAT efficacy compared to pH values. Comprehensive determination of parameters affecting NAT efficacy and improved food formulation will promote sustainable food/crop production, food safety, and public health.
RESUMO
Women reliant on mostly rice-based diets can have inadequate thiamine intake, placing breastfed infants at risk of thiamine deficiency and, in turn, physical and cognitive impairments. We investigated the impact of maternal thiamine supplementation doses on infants' cognitive, motor, and language development across the first year. In this double-blind, four-parallel-arm, randomized controlled trial, healthy mothers of exclusively breastfed newborn infants were recruited in Kampong Thom, Cambodia. At 2 weeks postnatal, women (n = 335) were randomized to one of four treatment groups to consume one capsule/day with varying amounts of thiamine for 22 weeks: 0, 1.2, 2.4, and 10 mg. At 2, 12, 24, and 52 weeks of age, infants were assessed with the Mullen Scales of Early Learning (MSEL) and the Caregiver Reported Early Development Instrument (CREDI). Multiple regression and mixed effects modeling suggest that by 6 months of age, the highest maternal thiamine dose (10 mg/day) held significant benefits for infants' language development, but generally not for motor or visual reception development. Despite having achieved standardized scores on the MSEL that approximated U.S. norms by 6 months, infants showed a significant drop relative to these norms in both language domains following trial completion, indicating that nutritional interventions beyond 6 months may be necessary.