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1.
bioRxiv ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-39005263

RESUMO

Background: Tick bites often promote local allergic reactions in the skin and predispose to red meat allergy. The mechanisms involved in these processes are not fully understood. Here we investigated the local changes to the skin and intestine induced by tick bites. Methods: C3H/HEN or Balb/c mice were subjected to either tick bites by Ixodes ricinus ( I. ricinus ) or mechanical skin injury. Skin or intestine was analyzed a different time point by transcriptomic and histological techniques. Results: Our results indicate that I. ricinus bites promote epidermal hyperplasia, spongiosis and an accumulation of eosinophils and mast cells in the bitten skin. In addition, I. ricinus bites promote the expression of genes and activate pathways also induced by mechanical skin injury elicited by tape stripping. Remarkably, similar to tape stripping, I. ricinus bites promote an increase in total serum IgE, and intestinal tuft cell and mast cell expansion. Conclusion: I. ricinus bites in mice promote cutaneous inflammation that resembles allergic skin inflammation, as well as intestinal changes that could play a role in the predisposition to red meat allergy.

2.
Adv Healthc Mater ; : e2401195, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38824416

RESUMO

Hydrogels are dynamically evolving 3D networks composed of hydrophilic polymer scaffolds with significant applications in the healthcare and environmental sectors. Notably, protein-based hydrogels mimic the extracellular matrix, promoting cell adhesion. Further enhancing cell proliferation within these scaffolds are matrix-metalloproteinase-triggered amino acid motifs. Integration of cell-friendly modules like peptides and proteins expands hydrogel functionality. These exceptional properties position hydrogels for diverse applications, including biomedicine, biosensors, environmental remediation, and the food industry. Despite significant progress, there is ongoing research to optimize hydrogels for biomedical and environmental applications further. Engineering novel hydrogels with favorable characteristics is crucial for regulating tissue architecture and facilitating ecological remediation. This review explores the synthesis, physicochemical properties, and biological implications of various hydrogel types and their extensive applications in biomedicine and environmental sectors. It elaborates on their potential applications, bridging the gap between advancements in the healthcare sector and solutions for environmental issues.

3.
J Allergy Clin Immunol ; 153(5): 1344-1354.e5, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38336257

RESUMO

BACKGROUND: Atopic dermatitis skin lesions exhibit increased infiltration by basophils. Basophils produce IL-4, which plays an important role in the pathogenesis of atopic dermatitis. OBJECTIVE: We sought to determine the role of basophils in a mouse model of antigen-driven allergic skin inflammation. METHODS: Wild-type mice, mice with selective and inducible depletion of basophils, and mice expressing Il4-driven enhanced green fluorescent protein were subjected to epicutaneous sensitization with ovalbumin or saline. Sensitized skin was examined by histology for epidermal thickening. Cells were analyzed for surface markers and intracellular expression of enhanced green fluorescent protein by flow cytometry. Gene expression was evaluated by real-time reverse transcription-quantitative PCR. RESULTS: Basophils were important for epidermal hyperplasia, dermal infiltration by CD4+ T cells, mast cells, and eosinophils in ovalbumin-sensitized mouse skin and for the local and systemic TH2 response to epicutaneous sensitization. Moreover, basophils were the major source of IL-4 in epicutaneous-sensitized mouse skin and promote the ability of dendritic cells to drive TH2 polarization of naive T cells. CONCLUSION: Basophils play an important role in the development of allergic skin inflammation induced by cutaneous exposure to antigen in mice.


Assuntos
Basófilos , Dermatite Atópica , Interleucina-4 , Ovalbumina , Células Th2 , Animais , Basófilos/imunologia , Camundongos , Interleucina-4/imunologia , Interleucina-4/genética , Dermatite Atópica/imunologia , Dermatite Atópica/patologia , Ovalbumina/imunologia , Células Th2/imunologia , Pele/imunologia , Pele/patologia , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos BALB C , Modelos Animais de Doenças , Células Dendríticas/imunologia , Camundongos Transgênicos , Mastócitos/imunologia
4.
J Invest Dermatol ; 144(8): 1784-1797.e4, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38286187

RESUMO

Physical trauma disrupts skin barrier function. How the skin barrier recovers is not fully understood. We evaluated in mice the mechanism of skin barrier recovery after mechanical injury inflicted by tape stripping. Tape stripping disrupted skin barrier function as evidenced by increased transepidermal water loss. We show that tape stripping induces IL-1-, IL-23-, and TCRγδ+-dependent upregulation of cutaneous Il17a and Il22 expression. We demonstrate that IL-17A and IL-22 induce epidermal hyperplasia, promote neutrophil recruitment, and delay skin barrier function recovery. Neutrophil depletion improved the recovery of skin barrier function and decreased epidermal hyperplasia. Single-cell RNA sequencing and flow cytometry analysis of skin cells revealed basophil infiltration into tape-stripped skin. Basophil depletion upregulated Il17a expression, increased neutrophil infiltration, and delayed skin barrier recovery. Comparative analysis of genes differentially expressed in tape-stripped skin of basophil-depleted mice and Il17a-/- mice indicated that basophils counteract the effects of IL-17A on the expression of epidermal and lipid metabolism genes important for skin barrier integrity. Our results demonstrate that basophils play a protective role by downregulating Il17a expression after mechanical skin injury, thereby counteracting the adverse effect of IL-17A on skin barrier function recovery, and suggest interventions to accelerate this recovery.


Assuntos
Basófilos , Interleucina-17 , Interleucinas , Animais , Camundongos , Basófilos/imunologia , Interleucina-17/metabolismo , Interleucinas/metabolismo , Interleucinas/genética , Pele/lesões , Pele/patologia , Pele/imunologia , Pele/metabolismo , Camundongos Knockout , Modelos Animais de Doenças , Interleucina 22 , Perda Insensível de Água/imunologia , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos , Epiderme/lesões , Epiderme/patologia , Epiderme/imunologia , Epiderme/metabolismo , Recuperação de Função Fisiológica , Feminino
6.
Cell ; 186(24): 5375-5393.e25, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37995657

RESUMO

Itch is an unpleasant sensation that evokes a desire to scratch. The skin barrier is constantly exposed to microbes and their products. However, the role of microbes in itch generation is unknown. Here, we show that Staphylococcus aureus, a bacterial pathogen associated with itchy skin diseases, directly activates pruriceptor sensory neurons to drive itch. Epicutaneous S. aureus exposure causes robust itch and scratch-induced damage. By testing multiple isogenic bacterial mutants for virulence factors, we identify the S. aureus serine protease V8 as a critical mediator in evoking spontaneous itch and alloknesis. V8 cleaves proteinase-activated receptor 1 (PAR1) on mouse and human sensory neurons. Targeting PAR1 through genetic deficiency, small interfering RNA (siRNA) knockdown, or pharmacological blockade decreases itch and skin damage caused by V8 and S. aureus exposure. Thus, we identify a mechanism of action for a pruritogenic bacterial factor and demonstrate the potential of inhibiting V8-PAR1 signaling to treat itch.


Assuntos
Peptídeo Hidrolases , Prurido , Receptor PAR-1 , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Humanos , Camundongos , Peptídeo Hidrolases/metabolismo , Prurido/microbiologia , Receptor PAR-1/metabolismo , Staphylococcus aureus/enzimologia , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/fisiologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia
7.
PLoS One ; 18(6): e0288112, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37390081

RESUMO

The purpose of the systematic review was to synthesize the literature on children's outcomes across different living arrangements (nuclear families, shared physical custody [SPC], lone physical custody [LPC]) by extracting and structuring relevant theoretical hypotheses (selection, instability, fewer resources, and stressful mobility) and comparing the empirical findings against these hypotheses. Following the PRISMA guidelines, the review included 39 studies conducted between January 2010-December 2022 and compared the living arrangements across five domains of children's outcomes: emotional, behavioral, relational, physical, and educational. The results showed that children's outcomes were the best in nuclear families but in 75% of the studies children in SPC arrangements had equal outcomes. Children in LPC tended to report the worst outcomes. When compared with the different theoretical hypotheses, the results were the most consistent with fewer resources hypothesis which suggests that children especially in LPC families have fewer relational and economic resources whereas children in SPC families are better able to maintain resources from both parents.


Assuntos
Emoções , Núcleo Familiar , Criança , Humanos , Escolaridade , Pais , Exame Físico
8.
J Allergy Clin Immunol ; 152(4): 907-915, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37315811

RESUMO

BACKGROUND: Skin colonization with Staphylococcus aureus aggravates atopic dermatitis and exaggerates allergic skin inflammation in mice. IL-4 receptor α (IL-4Rα) blockade is beneficial in atopic dermatitis and reduces Saureus skin colonization through unknown mechanisms. The cytokine IL-17A restrains Saureus growth. OBJECTIVES: This study sought to examine the effect of IL-4Rα blockade on Saureus colonization at sites of allergic skin inflammation in mice and determine the mechanism involved. METHODS: BALB/c mice were epicutaneously sensitized with ovalbumin (OVA). Immediately after, PSVue 794-labeled S aureus strain SF8300 or saline was applied and a single dose of anti-IL-4Rα blocking antibody, a mixture of anti-IL-4Rα and anti-IL-17A blocking antibodies, or IgG isotype controls were administered intradermally. Saureus load was assessed 2 days later by in vivo imaging and enumeration of colony forming units. Skin cellular infiltration was examined by flow cytometry and gene expression by quantitative PCR and transcriptome analysis. RESULTS: IL-4Rα blockade decreased allergic skin inflammation in OVA-sensitized skin, as well as in OVA-sensitized and Saureus-exposed skin, evidenced by significantly decreased epidermal thickening and reduced dermal infiltration by eosinophils and mast cells. This was accompanied by increased cutaneous expression of Il17a and IL-17A-driven antimicrobial genes with no change in Il4 and Il13 expression. IL-4Rα blockade significantly decreased Saureus load in OVA-sensitized and S aureus-exposed skin. IL-17A blockade reversed the beneficial effect of IL-4Rα blockade on Saureus clearance and reduced the cutaneous expression of IL-17A-driven antimicrobial genes. CONCLUSIONS: IL-4Rα blockade promotes Saureus clearance from sites of allergic skin inflammation in part by enhancing IL-17A expression.


Assuntos
Anti-Infecciosos , Dermatite Atópica , Camundongos , Animais , Dermatite Atópica/tratamento farmacológico , Interleucina-17/genética , Ovalbumina , Inflamação , Pele , Antígenos , Receptores de Interleucina-4 , Camundongos Endogâmicos BALB C
9.
J Neurogastroenterol Motil ; 29(2): 218-228, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37019866

RESUMO

Background/Aims: Motility, stool characteristics, and microbiota composition are expected to modulate probiotics' passage through the gut but their effects on persistence after intake cessation remain uncharacterized. This pilot, open-label study aims at characterizing probiotic fecal detection parameters (onset, persistence, and duration) and their relationship with whole gut transit time (WGTT). Correlations with fecal microbiota composition are also explored. Methods: Thirty healthy adults (30.4 ± 13.3 years) received a probiotic (30 × 109 CFU/capsule/day, 2 weeks; containing Lactobacillus helveticus R0052, Lacticaseibacillus paracasei HA-108, Bifidobacterium breve HA-129, Bifidobacterium longum R0175, and Streptococcus thermophilus HA-110). Probiotic intake was flanked by 4-week washout periods, with 18 stool collections throughout the study. WGTT was measured using 80% recovery of radio-opaque markers. Results: Tested strains were detected in feces ~1-2 days after first intake and persistence after intake cessation was not significantly different for R0052, HA-108, and HA-129 (~3-6 days). We identified 3 WGTT subgroups within this population (named Fast, Intermediate, and Slow), which could be classified by machine learning with high accuracy based on differentially abundant taxa. On average, R0175 persisted significantly longer in the intermediate WGTT subgroup (~8.5 days), which was mainly due to 6 of the 13 Intermediate participants for whom R0175 persisted ≥ 15 days. Machine learning classified these 13 participants according to their WGTT cluster (≥ 15 days or < 5 days) with high accuracy, highlighting differentially abundant taxa potentially associated with R0175 persistence. Conclusion: These results support the notion that host-specific parameters such as WGTT and microbiota composition should be considered when designing studies involving probiotics, especially for the optimization of washout duration in crossover studies but also for the definition of enrollment criteria or supplementation regimen in specific populations.

10.
Nutr Clin Pract ; 38(1): 88-101, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36286334

RESUMO

Oral nutrition supplements (ONS) are widely recommended for the management of unintentional weight loss in patient populations, long-term care residents, and community-dwelling older adults. Most marketed ONS are ultra-processed, with precision nutrition and aseptic composition, as well as convenience and availability, driving their selection. However, therapeutic effectiveness is mixed and the potential health risks of consuming ultra-processed ONS long-term in lieu of less-processed foods have received little attention. A diverse and balanced microbiota supporting immunity and wellness is maintained by a diet rich in plant-sourced foods. The implications of ultra-processed ONS displacing plant-sourced foods, and specifically the potential for undesirable impacts on the gut microbiota, require consideration. Most ONS are either devoid of fiber or are supplemented with isolated or purified fibers that may contribute to adverse gastrointestinal symptoms and appetite suppression. In contrast, the diversity of microbial-available, nondigestible carbohydrates, together with the array of phytochemicals found in plant-sourced foods, support microbial diversity and its resiliency. This review outlines the clinical dilemma of recommending commercial ultra-processed ONS vs nutritionally adequate (eg, high-energy/high-protein) foods and beverages that contribute to diet quality, maintenance of a diverse and stable gut microbiota composition, and support nutrition status and health. Ultra-processed ONS may fall short of expected health benefits, and overreliance may potentially contribute to the risk for patient and older adult populations because of the displacement of a variety of healthful foods.


Assuntos
Dieta , Estado Nutricional , Humanos , Idoso , Suplementos Nutricionais/efeitos adversos , Redução de Peso , Apoio Nutricional , Fast Foods , Manipulação de Alimentos
11.
Biomedica ; 41(Sp. 2): 48-61, 2021 10 15.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34669278

RESUMO

INTRODUCTION: The studies on knowledge, attitudes, and practices (KAP) regarding COVID-19 help to identify erroneous concepts and inadequate practices related to the disease. This baseline information is essential to design effective strategies and improve adherence to prevention measures. OBJECTIVE: To identify the COVID-19-related KAP in Venezuelan patients screened at the Hospital Universitario de Caracas triage tent. MATERIALS AND METHODS: We conducted a cross-sectional study among 215 patients between April 25th and May 25th, 2020, with in-person interviews using a KAP survey. RESULTS: Most surveyed patients (53.5%) were asymptomatic. Most of them, both from the symptomatic and the asymptomatic groups, had adequate knowledge about the symptoms and transmission of the disease and the majority said they were practicing quarantine, frequent handwashing, and the use of face masks in public areas. However, the daily replacement of cloth face masks was more frequent in the asymptomatic group whereas replacement every three days was more frequent in the symptomatic group. Finally, more than half of the participants admitted having been in crowded places, a common practice among the symptomatic compared to the asymptomatic patients. CONCLUSIONS: This is the first KAP study in Venezuela about COVID-19. Knowledge and practices among Venezuelans could be improved by strengthening education and training programs. This information from the early phase of the pandemic in Venezuela may contribute to the design of COVID-19 promotion and prevention strategies.


Introducción: Los estudios sobre conocimientos, actitudes y prácticas (CAP) sobre COVID-19 ayudan a identificar conceptos erróneos y prácticas inadecuadas relacionadas con la enfermedad. Esta información de referencia es fundamental para diseñar estrategias efectivas y mejorar la adherencia a las medidas de prevención. Objetivo: Identificar la CAP relacionada con COVID-19 en pacientes venezolanos cribados en la carpa de triaje del Hospital Universitario de Caracas. Materiales y métodos: Realizamos un estudio transversal entre 215 pacientes entre el 25 de abril y el 25 de mayo de 2020, con entrevistas en persona utilizando una encuesta KAP. Resultados: La mayoría de los pacientes encuestados (53,5%) se encontraban asintomáticos. La mayoría de ellos, tanto del grupo sintomático como asintomático, tenían un conocimiento adecuado sobre los síntomas y la transmisión de la enfermedad y la mayoría dijo que practicaban la cuarentena, el lavado frecuente de manos y el uso de mascarillas en las áreas públicas. Sin embargo, el reemplazo diario de mascarillas de tela fue más frecuente en el grupo asintomático, mientras que el reemplazo cada tres días fue más frecuente en el grupo sintomático. Finalmente, más de la mitad de los participantes admitieron haber estado en lugares concurridos, una práctica común entre los sintomáticos en comparación con los asintomáticos. Conclusiones: Este es el primer estudio CAP en Venezuela sobre COVID-19. El conocimiento y las prácticas entre los venezolanos podrían mejorarse fortaleciendo los programas de educación y capacitación. Esta información de la fase inicial de la pandemia en Venezuela puede contribuir al diseño de estrategias de promoción y prevención del COVID-19.


Assuntos
COVID-19/prevenção & controle , COVID-19/transmissão , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Infecções Assintomáticas/epidemiologia , Estudos Transversais , Aglomeração , Feminino , Desinfecção das Mãos , Inquéritos Epidemiológicos/métodos , Inquéritos Epidemiológicos/estatística & dados numéricos , Humanos , Masculino , Máscaras/estatística & dados numéricos , Distanciamento Físico , Avaliação de Sintomas , Triagem , Venezuela/epidemiologia
12.
Biology (Basel) ; 10(10)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34681103

RESUMO

Manganese (Mn) oxidation is performed through oxidative Mn-oxidizing bacteria (MnOxb) as the main bio-weathering mechanism for Mn(III/IV) deposits during soil formation. However, with an increase in temperature, the respiration rate also increases, producing Reactive Oxygen Species (ROS) as by-products, which are harmful to microbial cells. We hypothesize that bacterial ROS oxidize Mn(II) to Mn(III/IV) as a secondary non-enzymatic temperature-dependent mechanism for cell protection. Fourteen MnOxb were isolated from Antarctic soils under the global warming effect, and peroxidase (PO) activity, ROS, and Mn(III/IV) production were evaluated for 120 h of incubation at 4 °C, 15 °C, and 30 °C. ROS contributions to Mn oxidation were evaluated in Arthrobacter oxydans under antioxidant (Trolox) and ROS-stimulated (menadione) conditions. The Mn(III/IV) concentration increased with temperature and positively correlated with ROS production. ROS scavenging with Trolox depleted the Mn oxidation, and ROS-stimulant increased the Mn precipitation in A. oxydans. Increasing the Mn(II) concentration caused a reduction in the membrane potential and bacterial viability, which resulted in Mn precipitation on the bacteria surface. In conclusion, bacterial ROS production serves as a complementary non-enzymatic temperature-dependent mechanism for Mn(II) oxidation as a response in warming environments.

13.
Biomédica (Bogotá) ; 41(supl.2): 48-61, oct. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1355759

RESUMO

Abstract | Introduction: The studies on knowledge, attitudes, and practices (KAP) regarding COVID-19 help to identify erroneous concepts and inadequate practices related to the disease. This baseline information is essential to design effective strategies and improve adherence to prevention measures. Objective: To identify the COVID-19-related KAP in Venezuelan patients screened at the Hospital Universitario de Caracas triage tent. Materials and methods: We conducted a cross-sectional study among 215 patients between April 25th and May 25th, 2020, with in-person interviews using a KAP survey. Results: Most surveyed patients (53.5%) were asymptomatic. Most of them, both from the symptomatic and the asymptomatic groups, had adequate knowledge about the symptoms and transmission of the disease and the majority said they were practicing quarantine, frequent handwashing, and the use of face masks in public areas. However, the daily replacement of cloth face masks was more frequent in the asymptomatic group whereas replacement every three days was more frequent in the symptomatic group. Finally, more than half of the participants admitted having been in crowded places, a common practice among the symptomatic compared to the asymptomatic patients. Conclusions: This is the first KAP study in Venezuela about COVID-19. Knowledge and practices among Venezuelans could be improved by strengthening education and training programs. This information from the early phase of the pandemic in Venezuela may contribute to the design of COVID-19 promotion and prevention strategies.


Resumen | Introducción. Los estudios de conocimientos, actitudes y prácticas (CAP) relacionados con la Covid-19 permiten establecer los conceptos erróneos y las prácticas inadecuadas en torno a esta enfermedad, información fundamental para diseñar estrategias eficaces y mejorar el cumplimiento de las medidas de prevención. Objetivo. Establecer los conocimientos, actitudes y prácticas relacionadas con la Covid-19 en pacientes venezolanos cribados en la carpa de triaje del Hospital Universitario de Caracas. Materiales y métodos. Se hizo un estudio transversal en 215 pacientes entre el 25 de abril y el 25 de mayo de 2020, mediante entrevistas personales y utilizando una encuesta sobre conocimientos, actitudes y prácticas. Resultados. La mayoría (53,5 %) de los pacientes encuestados se encontraba asintomática; los encuestados tenían un conocimiento adecuado sobre los síntomas y la transmisión de la enfermedad, sin distinción entre sintomáticos y asintomáticos. La mayoría de ellos indicó estar respetando las prácticas de cuarentena, lavado de manos frecuente y uso de tapabocas en público; sin embargo, el reemplazo diario de los tapabocas de tela fue más frecuente en el grupo de los asintomáticos, en tanto que el reemplazo cada tres días fue más común entre los sintomáticos. Por último, más de la mitad de los participantes admitió haber estado en lugares concurridos, siendo esta práctica más frecuente entre los sintomáticos que entre los asintomáticos. Conclusiones. Este es el primer estudio de conocimientos, actitudes y prácticas sobre la Covid-19 en Venezuela. El conocimiento y las prácticas de los venezolanos podrían mejorar mediante el fortalecimiento de los programas de educación y capacitación. Esta información, obtenida durante la fase inicial de la pandemia en Venezuela, podría contribuir al diseño de estrategias de promoción y prevención de la Covid-19.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Infecções por Coronavirus , Venezuela , Promoção da Saúde
14.
J Cell Physiol ; 236(9): 6643-6656, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33533043

RESUMO

Aberrant expression of CD43 in malignant tumors of nonhematopoietic origin such as those from lung, cervix, colon, and breast has been shown to correlate with poor prognosis, providing tumor cells with enhanced motility, anchorage-independent growth, and in vivo tumor size, while protecting the cells of NK lysis and apoptosis. To further characterize the role of CD43 in cell transformation, we tested whether interfering its expression modified the capacity of the A549 non-small cell lung cancer cells to secrete molecules contributing to malignancy. The proteomic analysis of the secretome of serum-starved A549 cells revealed that cells expressing normal levels of CD43 released significantly high levels of molecules involved in extracellular matrix organization, angiogenesis, platelet degranulation, collagen degradation, and inflammation, as compared to CD43 RNAi cells. This data reveals a novel and unexpected role for CD43 in lung cancer development, mainly in remodeling the tumor microenvironment.


Assuntos
Matriz Extracelular/metabolismo , Leucossialina/metabolismo , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/metabolismo , Neovascularização Patológica/metabolismo , Células A549 , Inativação Gênica , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Microambiente Tumoral
15.
BMC Res Notes ; 13(1): 364, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32746904

RESUMO

OBJECTIVE: To determine if fermented soy supplementation relieves heartburn and improves gastrointestinal symptoms and quality of life, a randomized, double-blind parallel study was conducted with adults experiencing mild or moderate heartburn. Participants consumed up to 3, 1 g sachets of flavored, Lactobacillus delbrueckii fermented with soy flour (n = 23) or placebo (maltodextrin) (n = 27) sachets per heartburn incident as needed for 3 weeks. Symptom intensity at 5, 15, and 30 min post-administration was assessed using a Likert-like scale. The Gastrointestinal Symptoms Rating Scale (GSRS) and Gastro-esophageal Reflux Disease Quality of Life Questionnaire (GERD-QOL) were administered at baseline, post-intervention and following a 1-week washout. RESULTS: No significant differences between groups were seen for heartburn severity or frequency, GSRS syndromes, or GERD-QOL domains. However, individual QOL items related to inconvenience of taking medications, fear of eating, inability to concentrate at work, and disturbance of after-meal activities and rest improved with fermented soy compared to placebo. Frequency of heartburn, diarrhea, and bloating improved during washout vs. baseline for the fermented soy group compared to placebo. Lactobacillus delbrueckii fermented soy supplementation improved QOL indicators and may decrease heartburn occurrence over time vs. an acute effect; efficacy of daily intake and longer duration requires investigation.


Assuntos
Refluxo Gastroesofágico , Qualidade de Vida , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Azia/tratamento farmacológico , Humanos , Inquéritos e Questionários , Resultado do Tratamento
16.
ChemSusChem ; 13(23): 6360-6369, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32672415

RESUMO

A straightforward procedure has been developed to prepare a porous carbon material decorated with iron by direct pyrolysis of a mixture of a porous polymer and iron chloride. Characterization of the material with X-ray diffraction, X-ray absorption spectroscopy, and electron microscopy indicates the presence of iron carbide nanoparticles encapsulated inside the carbon matrix, and elemental mapping and cyanide poisoning experiments demonstrate the presence of atomic Fe centers, albeit in trace amounts, which are active sites for electrochemical CO2 reduction. The encapsulated iron carbide nanoparticles are found to boost the catalytic activity of atomic Fe sites in the outer carbon layers, rendering the material highly active and selective for CO2 reduction, although these atomic Fe sites are only present in trace amounts. The target material exhibits near-unity selectivity (98 %) for CO2 -to-CO conversion at a small overpotential (410 mV) in water. Furthermore, the material holds potential for practical application, as a current density over 30 mA cm-2 and a selectivity of 93 % can be achieved in a flow cell.

17.
Prog Mol Biol Transl Sci ; 171: 237-263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32475524

RESUMO

Although there is associative evidence linking fecal microbiome profile to health and disease, many studies have not considered the confounding effects of dietary intake. Consuming food provides fermentable substrate which sustains the microbial ecosystem that resides with most abundance in the colon. Western, Mediterranean and vegetarian dietary patterns have a role in modulating the gut microbiota, as do trending restrictive diets such the paleolithic and ketogenic. Altering the amount or ratio of carbohydrate, protein and fat, particularly at the extremes of intake, impacts the microbiome. Diets high in fermentable carbohydrates support the relative abundance of Bifidobacterium, Prevotella, Ruminococcus, Dorea and Roseburia, among others, capable of degrading polysaccharides, oligosaccharides and sugars. Conversely, very high fat diets increase bile-resistant organisms such as Bilophila and Bacteroides. Food form, whole foods vs. ultra-processed, alters the provision of macronutrient substrate to the colon due to differing digestibility, and thereby may impact the microbiota and its metabolic activity. In addition, phytochemicals in plant-based foods have specific and possibly prebiotic effects on the microbiome. Further, food ingredients such as certain low-calorie sweeteners enhance Bifidobacterium spp. The weight of evidence to date suggests a high level of interindividual variability in the human microbiome vs. clearly defined, dietary-induced profiles. Healthful dietary patterns, emphasizing plant foods high in microbial-available carbohydrate, support favorable microbiome profiles active in saccharolytic fermentation. Future research into diet and microbiome should consider the balance of gut microbial-generated metabolites, an important link between microbiome profile and human health.


Assuntos
Dieta , Microbiota/efeitos dos fármacos , Nutrientes/administração & dosagem , Nutrientes/análise , Humanos
18.
Curr Dev Nutr ; 4(2): nzaa005, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32025615

RESUMO

BACKGROUND: Consuming foods with added fiber may help older adults achieve fiber recommendations; however, many high-fiber ingredients have little effect on laxation and may contribute to unpleasant gastrointestinal side effects. OBJECTIVES: The aim of the study was to determine the effects of consuming snacks fortified with pea hull fiber (PHF) on stool frequency and form, gastrointestinal symptoms, and appetite in older adults. An exploratory aim was to determine if PHF altered the microbiota profile. METHODS: A 10-wk, randomized, blinded, crossover study was carried out. Following a 2-wk baseline period, participants [aged (mean ± SD) 69.7 ± 6.5 y; n = 31; 14 men, 17 women] consumed snacks providing 10 g/d of PHF or a control, each for 2-wk periods followed by 2-wk washouts. Participants used the Bristol Stool Form Scale (BSFS) to record daily stool frequency and gastrointestinal symptoms, and completed the Gastrointestinal Symptom Rating Scale (GSRS) and Simplified Nutritional Appetite Questionnaire (SNAQ) biweekly. One stool was collected per period for 16S ribosomal RNA high-throughput amplicon sequencing of the fecal microbiota profile. RESULTS: Participants reported 1.63 ± 0.05 stools/d and 76.6% normal transit stool form at baseline and no change with PHF. GSRS syndrome scores were similarly unchanged. Daily abdominal noises and bloating were higher for PHF versus control, and flatulence was higher for PHF versus baseline, suggesting fermentation in some individuals. There was no evidence to suggest a common PHF-induced microbiome response for the group as a whole; however, a subgroup of participants (n = 7) who responded with increased flatulence (fermenters), harbored many different taxa than nonfermenters, and demonstrated lower abundance of Clostridiales with PHF. Appetite was unchanged with PHF. CONCLUSIONS: PHF did not modulate stool form or frequency in older adults with normal bowel habits. Because snacks fortified with PHF did not suppress appetite, PHF may be an appropriate fiber source for older adults at nutritional risk. Microbiome profile may be predictive of gastrointestinal symptom response to PHF. This trial was registered at www.clinicaltrials.gov as NCT02778230.

19.
Angew Chem Int Ed Engl ; 58(45): 16172-16176, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31496012

RESUMO

Conversion of CO2 into valuable molecules is a field of intensive investigation with the aim of developing scalable technologies for making fuels using renewable energy sources. While electrochemical reduction into CO and formate are approaching industrial maturity, a current challenge is obtaining more reduced products like methanol. However, literature on the matter is scarce, and even more for the use of molecular catalysts. Here, we demonstrate that cobalt phthalocyanine, a well-known catalyst for the electrochemical conversion of CO2 to CO, can also catalyze the reaction from CO2 or CO to methanol in aqueous electrolytes at ambient conditions of temperature and pressure. The studies identify formaldehyde as a key intermediate and an unexpected pH effect on selectivity. This paves the way for establishing a sequential process where CO2 is first converted to CO which is subsequently used as a reactant to produce methanol. Under ideal conditions, the reaction shows a global Faradaic efficiency of 19.5 % and chemical selectivity of 7.5 %.

20.
Nat Commun ; 10(1): 3602, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399585

RESUMO

Molecular catalysts that combine high product selectivity and high current density for CO2 electrochemical reduction to CO or other chemical feedstocks are urgently needed. While earth-abundant metal-based molecular electrocatalysts with high selectivity for CO2 to CO conversion are known, they are characterized by current densities that are significantly lower than those obtained with solid-state metal materials. Here, we report that a cobalt phthalocyanine bearing a trimethyl ammonium group appended to the phthalocyanine macrocycle is capable of reducing CO2 to CO in water with high activity over a broad pH range from 4 to 14. In a flow cell configuration operating in basic conditions, CO production occurs with excellent selectivity (ca. 95%), and good stability with a maximum partial current density of 165 mA cm-2 (at -0.92 V vs. RHE), matching the most active noble metal-based nanocatalysts. These results represent state-of-the-art performance for electrolytic carbon dioxide reduction by a molecular catalyst.

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