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1.
Chem Rev ; 123(23): 13693-13712, 2023 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-37975808

RESUMEN

An overview of Parkinson's disease (PD) prevalence, diagnosis, and currently available treatment options is provided. A comprehensive list of different classes of marketed pharmaceutical drug products and the syntheses of various drug substances are summarized based on published literature.


Asunto(s)
Antiparkinsonianos , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/epidemiología , Preparaciones Farmacéuticas , Antiparkinsonianos/clasificación , Prevalencia
2.
Chem Biodivers ; 20(11): e202300602, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37798811

RESUMEN

This study compared free and bound phenolic compounds in various marine microalgae species. It assessed total phenolic content (TPC), total flavonoid content (TFC) and total condensed tannin content (TCT) and their antioxidant capacities using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+ ) radical cation-based assay and ferric ion reducing antioxidant power assay. Liquid chromatography-mass spectrometry (LC-MS) was also employed to characterize the phenolic profiling. Results showed that free phenolic compounds ranged from 1.83-6.45 mg GAE/g d. w., while bound phenolic compounds ranged from 4.03-26.03 mg GAE/g d. w., indicating significant differences. These variations were consistent across assays, highlining unique profiles in different species. A total 10 phenolics were found in these seven microalgae, including 1 phenolic acid, 6 flavonoids, 1 other polyphenol and 2 lignans. 4'-O-methyl-(-)-epigallocatechin 7-O-glucuronide and chrysoeriol 7-O-glucoside in microalgae were firstly reported in microalgal samples. These findings have implications for future applications in industries.


Asunto(s)
Antioxidantes , Microalgas , Antioxidantes/química , Flavonoides/química , Fenoles/química , Extractos Vegetales/química
3.
Front Nutr ; 10: 1267287, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731395

RESUMEN

Introduction: Understanding the variations of oligosaccharide in breast milk contribute to better study how human milk oligosaccharides (HMOs) play a role in health-promoting benefits in infants. Methods: Six abundant HMOs, 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3-FL), Lacto-N-tetraose (LNT), Lacto-N-neotetraose (LNnT), 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL), in breast milk collected at 0-5 days, 10-15 days, 40-45 days, 200-240 days, and 300-400 days postpartum from six locations across China were analyzed using high-performance anion-exchange chromatography-pulsed amperometric detector. Results: The concentration of individual HMO fluctuated dynamically during lactational stages. The median ranges of 2'-FL, 3-FL, LNT, LNnT, 3'-SL, and 6'-SL across the five lactational stages were 935-2865 mg/L, 206-1325 mg/L, 300-1473 mg/L, 32-317 mg/L, 106-228 mg/L, and 20-616 mg/L, respectively. The prominent variation was observed in the content of 6'-SL, which demonstrates a pattern of initial increase followed by a subsequent decrease. Among the five lactational stages, the transitional milk has the highest concentration, which was 31 times greater than the concentration in mature milk at 300-400 days postpartum, where the content is the lowest. Geographical location also influenced the content of HMOs. LNT and LNnT were the highest in mature milk of mothers from Lanzhou among the six sites at 40-240 days postpartum. Breast milks were categorized into two groups base on the abundance of 2'-FL (high and low). There was no significant difference in the proportions of high and low 2'-FL phenotypes among the six sites, and the percentages of high and low 2'-FL phenotypes were 79% and 21%, respectively, across all sites in China. Discussion: This study provided a comprehensive dataset on 6 HMOs concentrations in Chinese breast milk during the extended postpartum period across a wide geographic range and stratified by high and low 2'-FL phenotypes.

4.
Nutrients ; 15(10)2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37242222

RESUMEN

Human milk represents an optimal source of nutrition during infancy. Milk also serves as a vehicle for the transfer of growth factors, commensal microbes, and prebiotic compounds to the immature gastrointestinal tract. These immunomodulatory and prebiotic functions of milk are increasingly appreciated as critical factors in the development of the infant gut and its associated microbial community. Advances in infant formula composition have sought to recapitulate some of the prebiotic and immunomodulatory functions of milk through human milk oligosaccharide (HMO) fortification, with the aim of promoting healthy development both within the gastrointestinal tract and systemically. Our objective was to investigate the effects of feeding formulas supplemented with the HMO 2'-fucosyllactose (2'-FL) on serum metabolite levels relative to breastfed infants. A prospective, randomized, double-blinded, controlled study of infant formulas (64.3 kcal/dL) fortified with varying levels of 2'-FL and galactooligosaccharides (GOS) was conducted [0.2 g/L 2'-FL + 2.2 g/L GOS; 1.0 g/L 2'-FL + 1.4 g/L GOS]. Healthy singleton infants age 0-5 days and with birth weight > 2490 g were enrolled (n = 201). Mothers chose to either exclusively formula-feed or breastfeed their infant from birth to 4 months of age. Blood samples were drawn from a subset of infants at 6 weeks of age (n = 35-40 per group). Plasma was evaluated by global metabolic profiling and compared to a breastfed reference group (HM) and a control formula (2.4 g/L GOS). Fortification of control infant formula with the HMO 2'-FL resulted in significant increases in serum metabolites derived from microbial activity in the gastrointestinal tract. Most notably, secondary bile acid production was broadly increased in a dose-dependent manner among infants receiving 2'-FL supplemented formula relative to the control formula. 2'-FL supplementation increased secondary bile acid production to levels associated with breastfeeding. Our data indicate that supplementation of infant formula with 2'-FL supports the production of secondary microbial metabolites at levels comparable to breastfed infants. Thus, dietary supplementation of HMO may have broad implications for the function of the gut microbiome in systemic metabolism. This trial was registered at with the U.S. National library of Medicine as NCT01808105.


Asunto(s)
Microbiota , Leche Humana , Femenino , Humanos , Lactante , Recién Nacido , Preescolar , Leche Humana/química , Estudios Prospectivos , Suplementos Dietéticos , Fórmulas Infantiles , Lactancia Materna , Prebióticos/análisis , Oligosacáridos/farmacología
5.
PLoS One ; 18(5): e0280979, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37196023

RESUMEN

Emerging infection diseases (EIDs) are an increasing threat to global public health, especially when the disease is newly emerging. Institutions of higher education (IHEs) are particularly vulnerable to EIDs because student populations frequently share high-density residences and strongly mix with local and distant populations. In fall 2020, IHEs responded to a novel EID, COVID-19. Here, we describe Quinnipiac University's response to SARS-CoV-2 and evaluate its effectiveness through empirical data and model results. Using an agent-based model to approximate disease dynamics in the student body, the University established a policy of dedensification, universal masking, surveillance testing via a targeted sampling design, and app-based symptom monitoring. After an extended period of low incidence, the infection rate grew through October, likely due to growing incidence rates in the surrounding community. A super-spreader event at the end of October caused a spike in cases in November. Student violations of the University's policies contributed to this event, but lax adherence to state health laws in the community may have also contributed. The model results further suggest that the infection rate was sensitive to the rate of imported infections and was disproportionately impacted by non-residential students, a result supported by the observed data. Collectively, this suggests that campus-community interactions play a major role in campus disease dynamics. Further model results suggest that app-based symptom monitoring may have been an important regulator of the University's incidence, likely because it quarantined infectious students without necessitating test results. Targeted sampling had no substantial advantages over simple random sampling when the model incorporated contact tracing and app-based symptom monitoring but reduced the upper boundary on 90% prediction intervals for cumulative infections when either was removed. Thus, targeted sampling designs for surveillance testing may mitigate worst-case outcomes when other interventions are less effective. The results' implications for future EIDs are discussed.


Asunto(s)
COVID-19 , Enfermedades Transmisibles Emergentes , Humanos , COVID-19/epidemiología , Universidades , SARS-CoV-2 , Vivienda
6.
Am J Physiol Gastrointest Liver Physiol ; 325(1): G23-G41, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37120853

RESUMEN

Necrotizing enterocolitis (NEC) is the leading cause of morbidity and mortality in premature infants. One of the most devastating complications of NEC is the development of NEC-induced brain injury, which manifests as impaired cognition that persists beyond infancy and which represents a proinflammatory activation of the gut-brain axis. Given that oral administration of the human milk oligosaccharides (HMOs) 2'-fucosyllactose (2'-FL) and 6'-sialyslactose (6'-SL) significantly reduced intestinal inflammation in mice, we hypothesized that oral administration of these HMOs would reduce NEC-induced brain injury and sought to determine the mechanisms involved. We now show that the administration of either 2'-FL or 6'-SL significantly attenuated NEC-induced brain injury, reversed myelin loss in the corpus callosum and midbrain of newborn mice, and prevented the impaired cognition observed in mice with NEC-induced brain injury. In seeking to define the mechanisms involved, 2'-FL or 6'-SL administration resulted in a restoration of the blood-brain barrier in newborn mice and also had a direct anti-inflammatory effect on the brain as revealed through the study of brain organoids. Metabolites of 2'-FL were detected in the infant mouse brain by nuclear magnetic resonance (NMR), whereas intact 2'-FL was not. Strikingly, the beneficial effects of 2'-FL or 6'-SL against NEC-induced brain injury required the release of the neurotrophic factor brain-derived neurotrophic factor (BDNF), as mice lacking BDNF were not protected by these HMOs from the development of NEC-induced brain injury. Taken in aggregate, these findings reveal that the HMOs 2'-FL and 6'-SL interrupt the gut-brain inflammatory axis and reduce the risk of NEC-induced brain injury.NEW & NOTEWORTHY This study reveals that the administration of human milk oligosaccharides, which are present in human breast milk, can interfere with the proinflammatory gut-brain axis and prevent neuroinflammation in the setting of necrotizing enterocolitis, a major intestinal disorder seen in premature infants.


Asunto(s)
Lesiones Encefálicas , Disfunción Cognitiva , Enterocolitis Necrotizante , Humanos , Recién Nacido , Lactante , Femenino , Animales , Ratones , Leche Humana/metabolismo , Factor Neurotrófico Derivado del Encéfalo , Enfermedades Neuroinflamatorias , Enterocolitis Necrotizante/etiología , Oligosacáridos/farmacología , Oligosacáridos/uso terapéutico , Oligosacáridos/análisis , Disfunción Cognitiva/prevención & control , Disfunción Cognitiva/complicaciones , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/metabolismo
7.
Food Funct ; 14(2): 899-910, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36537586

RESUMEN

Microalgae are a developing novel source of carbohydrates, phenolic compounds, carotenoids and proteins. In this study, in vitro digestion and colonic fermentation were conducted to examine the total phenolic content and potential antioxidant activity of four microalgal species (Chlorella sp., Spirulina sp., Dunaliella sp., and Isochrysis sp.). The bioaccessibility of targeted phenolic compounds and the short-chain fatty acid (SCFA) production were also estimated. Particularly, Spirulina sp. exhibited the highest total phenolic content (TPC) and free radical scavenging (2,2'-diphenyl-1-picrylhydrazyl, DPPH) capacity after gastrointestinal digestion of 7.93 mg gallic acid equivalents (GAE) per g and 2.35 mg Trolox equivalents (TE) per g. Meanwhile, it had the highest total flavonoid content (TFC) of 1.07 quercetin equivalents (QE) per g after 8 h of colonic fermentation. Dunaliella sp. and Isochrysis sp. showed comparable ferric reducing antioxidant power (FRAP) of 4.96 and 4.45 mg QE per g after 4 h of faecal reaction, respectively. p-hydroxybenzoic and caffeic acid almost completely decomposed after the intestine and fermented in the colon with the gut microflora. In Dunaliella sp. and Isochrysis sp., these phenolic acids were found in the colonic fermented residual, probably due to the presence of dietary fibre and the interactions with other components. All four species reached the highest values of SCFA production after 16 h, except Spirulina sp., which displayed the most increased total SCFA production after 8 h of fermentation. It is proposed that Spirulina sp. could be more beneficial to gut health.


Asunto(s)
Chlorella , Microalgas , Fermentación , Extractos Vegetales/química , Fenoles/química , Antioxidantes/química , Quercetina , Colon , Digestión
8.
Nutrients ; 14(19)2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36235783

RESUMEN

BACKGROUND: Human milk oligosaccharides (HMOs) are a group of breast milk carbohydrates exerting pivotal benefits for breastfed infants. Whether maternal diet is associated with breastmilk HMO composition has not been well-characterized. OBJECTIVES: We investigated the associations between dietary nutrient intake and HMO concentrations in a general pregnant and postpartum population. METHODS: A total of 383 breast milk samples and the corresponding food frequency questionnaires during 0-400 postpartum days from 277 mothers were collected. Six different HMOs were detected in mothers' milk. The correlation between nutrients and HMOs were analyzed using a linear mixed-effects model. RESULTS: We found plant nutrients, vitamin A, vitamin C and vegetables as positive predictors of 3-fucosyllactose; vitamin B1 and vitamin B2 were positive predictors for 2'-fucosyllactose level and the sum of 2'-fucosyllactose and 3-fucosyllactose; tocopherol and metal elements were positive predictors for 3'-sialyllactose; and metal elements were positively associated with the sum of all the six HMOs; the milk and lactose intake was a positive predictor of lacto-N-tetraose levels and the sum of lacto-N-tetraose and lacto-N-neotetraose. CONCLUSIONS: The results show that vegetables, vitamins and metal elements are dietary components positively associated with HMO concentrations.


Asunto(s)
Leche Humana , Verduras , Ácido Ascórbico , China , Femenino , Humanos , Lactante , Lactosa , Oligosacáridos , Embarazo , Riboflavina , Tiamina , Tocoferoles , Vitamina A , Vitamina K , Vitaminas
9.
PLoS Pathog ; 18(10): e1010855, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36191054

RESUMEN

Infection of the human gut by Salmonella enterica Typhimurium (STM) results in a localized inflammatory disease that is not mimicked in murine infections. To determine mechanisms by which neutrophils, as early responders to bacterial challenge, direct inflammatory programming of human intestinal epithelium, we established a multi-component human intestinal organoid (HIO) model of STM infection. HIOs were micro-injected with STM and seeded with primary human polymorphonuclear leukocytes (PMN-HIOs). PMNs did not significantly alter luminal colonization of Salmonella, but their presence reduced intraepithelial bacterial burden. Adding PMNs to infected HIOs resulted in substantial accumulation of shed TUNEL+ epithelial cells that was driven by PMN Caspase-1 activity. Inhibition of Caspases-1, -3 or -4 abrogated epithelial cell death and extrusion in the infected PMN-HIOs but only Caspase-1 inhibition significantly increased bacterial burden in the PMN-HIO epithelium. Thus, PMNs promote cell death in human intestinal epithelial cells through multiple caspases as a protective response to infection. IL-1ß was necessary and sufficient to induce cell shedding in the infected HIOs. These data support a critical innate immune function for human neutrophils in amplifying cell death and extrusion of human epithelial cells from the Salmonella-infected intestinal monolayer.


Asunto(s)
Neutrófilos , Infecciones por Salmonella , Animales , Humanos , Ratones , Caspasas/metabolismo , Células Epiteliales , Mucosa Intestinal/microbiología , Infecciones por Salmonella/metabolismo , Salmonella typhimurium
10.
Data Brief ; 42: 108104, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35434224

RESUMEN

To take advantage of the computing power offered by grid and opportunistic resources, the CERN Large Hadron Collider (LHC) experiments have adopted the Pilot-Job paradigm. In this work, we study the DIRAC Site Director, one of the existing Pilot-Job provisioning solutions, mainly developed and used by the beauty experiment (LHCb). The purpose is to improve the Pilot-Job submission rates and the throughput of the jobs on grid resources. To analyze the DIRAC Site Director mechanisms and assess our contributions, we collected data over 12 months from the LHCbDIRAC instance. We extracted data from the DIRAC databases and the logs. Data include (i) evolution of the number of Pilot-Jobs/jobs over time; (ii) slots available in grid Sites; (iii) number of jobs processed per Pilot-Job.

11.
Afr J Reprod Health ; 26(6): 36-44, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37585056

RESUMEN

Adolescent fertility rates are high in Kenya and increase the likelihood of maternal and infant morbidity and mortality. The objectives were to (1) explore the prevalence of unintended pregnancy among Maasai adolescent mothers, (2) understand the context in which pregnancy is occurring, and (3) suggest community-based strategies to prevent adolescent pregnancy. In in-depth, individual, qualitative interviews with Maasai females that gave birth during adolescence, pregnancy was unintended in 100% of cases. Our results suggest a desire among this population to prevent pregnancy and the need for contraception. Our recommendations include comprehensive sex education that targets very young adolescents, implementation of mechanisms to strive toward universal primary education, and the provision of resources and skills to adolescents that they need to practice safer sex.


Asunto(s)
Embarazo en Adolescencia , Embarazo , Adolescente , Femenino , Humanos , Embarazo en Adolescencia/prevención & control , Kenia/epidemiología , Anticoncepción , Educación Sexual , Embarazo no Planeado , Conducta Sexual
12.
J Org Chem ; 87(4): 1986-1995, 2022 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-34280307

RESUMEN

Foslevodopa (FLD, levodopa 4'-monophosphate, 3) and foscarbidopa (FCD, carbidopa 4'-monophosphate, 4) were identified as water-soluble prodrugs of levodopa (LD, 1) and carbidopa (CD, 2), respectively, which are useful for the treatment of Parkinson's disease. Herein, we describe asymmetric syntheses of FLD (3) and FCD (4) drug substances and their manufacture at pilot scale. The synthesis of FLD (3) employs a Horner-Wadsworth-Emmons olefination reaction followed by enantioselective hydrogenation of the double bond as key steps to introduce the α-amino acid moiety with the desired stereochemistry. The synthesis of FCD (4) features a Mizoroki-Heck reaction followed by enantioselective hydrazination to install the quaternary chiral center bearing a hydrazine moiety.


Asunto(s)
Enfermedad de Parkinson , Preparaciones Farmacéuticas , Carbidopa , Humanos , Hidrogenación , Levodopa/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico
13.
PLoS Pathog ; 17(10): e1009987, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34669717

RESUMEN

Salmonella enterica represents over 2500 serovars associated with a wide-ranging spectrum of disease; from self-limiting gastroenteritis to invasive infections caused by non-typhoidal serovars (NTS) and typhoidal serovars, respectively. Host factors strongly influence infection outcome as malnourished or immunocompromised individuals can develop invasive infections from NTS, however, comparative analyses of serovar-specific host responses have been constrained by reliance on limited model systems. Here we used human intestinal organoids (HIOs), a three-dimensional "gut-like" in vitro system derived from human embryonic stem cells, to elucidate similarities and differences in host responses to NTS and typhoidal serovars. HIOs discriminated between the two most prevalent NTS, Salmonella enterica serovar Typhimurium (STM) and Salmonella enterica serovar Enteritidis (SE), and typhoidal serovar Salmonella enterica serovar Typhi (ST) in epithelial cell invasion, replication and transcriptional responses. Pro-inflammatory signaling and cytokine output was reduced in ST-infected HIOs compared to NTS infections, consistent with early stages of NTS and typhoidal diseases. While we predicted that ST would induce a distinct transcriptional profile from the NTS strains, more nuanced expression profiles emerged. Notably, pathways involved in cell cycle, metabolism and mitochondrial functions were downregulated in STM-infected HIOs and upregulated in SE-infected HIOs. These results correlated with suppression of cellular proliferation and induction of host cell death in STM-infected HIOs and in contrast, elevated levels of reactive oxygen species production in SE-infected HIOs. Collectively, these results suggest that the HIO model is well suited to reveal host transcriptional programming specific to infection by individual Salmonella serovars, and that individual NTS may provoke unique host epithelial responses during intestinal stages of infection.


Asunto(s)
Perfilación de la Expresión Génica , Intestinos/microbiología , Intestinos/fisiopatología , Infecciones por Salmonella/microbiología , Infecciones por Salmonella/fisiopatología , Humanos , Organoides , Salmonella enterica , Serogrupo , Transcriptoma
14.
Nutrients ; 13(10)2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34684364

RESUMEN

Breastfeeding is the best source of nutrition during infancy and is associated with a broad range of health benefits. However, there remains a significant and persistent need for innovations in infant formula that will allow infants to access a wider spectrum of benefits available to breastfed infants. The addition of human milk oligosaccharides (HMOs) to infant formulas represents the most significant innovation in infant nutrition in recent years. Although not a direct source of calories in milk, HMOs serve as potent prebiotics, versatile anti-infective agents, and key support for neurocognitive development. Continuing improvements in food science will facilitate production of a wide range of HMO structures in the years to come. In this review, we evaluate the relationship between HMO structure and functional benefits. We propose that infant formula fortification strategies should aim to recapitulate a broad range of benefits to support digestive health, immunity, and cognitive development associated with HMOs in breastmilk. We conclude that acetylated, fucosylated, and sialylated HMOs likely confer important health benefits through multiple complementary mechanisms of action.


Asunto(s)
Salud del Lactante , Leche Humana/química , Oligosacáridos/metabolismo , Cognición , Humanos , Inmunomodulación , Lactante , Nutrientes/análisis , Oligosacáridos/química
15.
mBio ; 12(3)2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-34006652

RESUMEN

The intestinal epithelium is a primary interface for engagement of the host response by foodborne pathogens, like Salmonella enterica Typhimurium. While the interaction of S Typhimurium with the mammalian host has been well studied in transformed epithelial cell lines or in the complex intestinal environment in vivo, few tractable models recapitulate key features of the intestine. Human intestinal organoids (HIOs) contain a polarized epithelium with functionally differentiated cell subtypes, including enterocytes and goblet cells and a supporting mesenchymal cell layer. HIOs contain luminal space that supports bacterial replication, are more amenable to experimental manipulation than animals and are more reflective of physiological host responses. Here, we use the HIO model to define host transcriptional responses to S Typhimurium infection, also determining host pathways dependent on Salmonella pathogenicity island-1 (SPI-1)- and -2 (SPI-2)-encoded type 3 secretion systems (T3SS). Consistent with prior findings, we find that S Typhimurium strongly stimulates proinflammatory gene expression. Infection-induced cytokine gene expression was rapid, transient, and largely independent of SPI-1 T3SS-mediated invasion, likely due to continued luminal stimulation. Notably, S Typhimurium infection led to significant downregulation of host genes associated with cell cycle and DNA repair, leading to a reduction in cellular proliferation, dependent on SPI-1 and SPI-2 T3SS. The transcriptional profile of cell cycle-associated target genes implicates multiple miRNAs as mediators of S Typhimurium-dependent cell cycle suppression. These findings from Salmonella-infected HIOs delineate common and distinct contributions of SPI-1 and SPI-2 T3SSs in inducing early host responses during enteric infection and reinforce host cell proliferation as a process targeted by SalmonellaIMPORTANCESalmonella enterica serovar Typhimurium (S Typhimurium) causes a significant health burden worldwide, yet host responses to initial stages of intestinal infection remain poorly understood. Due to differences in infection outcome between mice and humans, physiological human host responses driven by major virulence determinants of Salmonella have been more challenging to evaluate. Here, we use the three-dimensional human intestinal organoid model to define early responses to infection with wild-type S Typhimurium and mutants defective in the SPI-1 or SPI-2 type-3 secretion systems. While both secretion system mutants show defects in mouse models of oral Salmonella infection, the specific contributions of each secretion system are less well understood. We show that S Typhimurium upregulates proinflammatory pathways independently of either secretion system, while the downregulation of the host cell cycle pathways relies on both SPI-1 and SPI-2. These findings lay the groundwork for future studies investigating how SPI-1- and SPI-2-driven host responses affect infection outcome and show the potential of this model to study host-pathogen interactions with other serovars to understand how initial interactions with the intestinal epithelium may affect pathogenesis.


Asunto(s)
Proteínas Bacterianas/genética , Enterocitos/microbiología , Perfilación de la Expresión Génica , Interacciones Huésped-Patógeno/genética , Proteínas de la Membrana/genética , Organoides/microbiología , Salmonella typhimurium/genética , Línea Celular , Regulación Bacteriana de la Expresión Génica , Humanos , Mucosa Intestinal/microbiología , Intestinos/citología , Intestinos/microbiología , Salmonella typhimurium/patogenicidad , Serogrupo , Factores de Virulencia
16.
Nat Commun ; 12(1): 262, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33431859

RESUMEN

The pathogenesis of ulcerative colitis (UC), a major type of inflammatory bowel disease, remains unknown. No model exists that adequately recapitulates the complexity of clinical UC. Here, we take advantage of induced pluripotent stem cells (iPSCs) to develop an induced human UC-derived organoid (iHUCO) model and compared it with the induced human normal organoid model (iHNO). Notably, iHUCOs recapitulated histological and functional features of primary colitic tissues, including the absence of acidic mucus secretion and aberrant adherens junctions in the epithelial barrier both in vitro and in vivo. We demonstrate that the CXCL8/CXCR1 axis was overexpressed in iHUCO but not in iHNO. As proof-of-principle, we show that inhibition of CXCL8 receptor by the small-molecule non-competitive inhibitor repertaxin attenuated the progression of UC phenotypes in vitro and in vivo. This patient-derived organoid model, containing both epithelial and stromal compartments, will generate new insights into the underlying pathogenesis of UC while offering opportunities to tailor interventions to the individual patient.


Asunto(s)
Colitis Ulcerosa/patología , Organoides/patología , Uniones Adherentes/metabolismo , Cadherinas/metabolismo , Progresión de la Enfermedad , Epitelio/patología , Fibroblastos/patología , Humanos , Inflamación/patología , Epiplón/trasplante , Fenotipo , Análisis de Componente Principal , Análisis de Secuencia de ARN , Sulfonamidas/farmacología , Transcriptoma/genética , beta Catenina/metabolismo
17.
J Colloid Interface Sci ; 589: 65-76, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33450461

RESUMEN

HYPOTHESIS: Bacillariophyceae (i.e., diatoms) are an important class of algae with potential use in the production of proteins and lipids including long-chain ω-3 polyunsaturated fatty acids. Biphasic extraction of microalgae lipids using water-immiscible solvents such as hexane, can avoid the excessive energy required to distil solvents from water, but generally requires energy-intensive rupture of the cells. The unique cell structure and surface chemistry of diatoms compared to other microalgae species might allow biphasic lipid extraction without prior cell rupture. EXPERIMENTS: The kinetics of biphasic lipid extraction from intact Navicula sp. cells was investigated during low-shear and high-shear mixing, and with prior or simultaneous application of ultrasound (20 kHz at 0.57 W/mL). Dynamic interfacial tension measurements and electron microscopic analysis were used to investigate lipid extraction in relation to interfacial behaviour and cell structure. RESULTS: High yields (>80%) of intracellular lipids were extracted from intact cells over the course of hours upon low-shear contacting with hexane. The cells associated with and stabilised the hexane-water interface, allowing hexane to infiltrate pores in the frustule component of the cell walls and access the intracellular lipids. It was shown that mucilaginous extracellular polymeric substances (EPS) bound to the cell walls acted as a barrier to solvent penetration into the cells. This EPS could be removed by prior ultrasonication. Biphasic extraction was greatly accelerated by shear applied by rotor-stator mixing or ultrasound. High-shear could remove mucilaginous EPS from the cell surfaces to facilitate direct contact of the cell surface with hexane and produced smaller emulsion droplets with increased surface area. The combination of high-shear in the presence of hexane resulted in the in-situ rupture of the cells, which greatly accelerated lipid extraction and allowed high yields of neutral lipid (>95%) to be recovered from freshly harvested cells within less than 5 min. The study demonstrated the ability of shear to enable simultaneous cell rupture and lipid extraction from a diatom alga based on its cell structure and interfacial behaviour.


Asunto(s)
Diatomeas , Microalgas , Biomasa , Lípidos , Solventes
18.
Stress ; 24(4): 413-420, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33222576

RESUMEN

Hair cortisol concentrations (HCC) were studied in mother-child dyads of La Romana, Dominican Republic (DR), a low-income city, and of the surrounding bateyes, sugarcane plantation villages with inhabitants frequently of Haitian descent. Populations of low socioeconomic status (SES) experience hypothalamic-pituitary-adrenal (HPA) axis dysregulation. Urban communities may be increasingly exposed to stressors such as crime and concentrated poverty whereas rural communities may be devoid of important community resources. As a result, the experience of stress in poverty may differ by place of residence. The goal of this study was to examine differences in HCC among urban and rural-dwelling mother-child dyads in socioeconomically disadvantaged communities surrounding La Romana, DR. Forty-five mother/child dyads were enrolled in La Romana and 45 at several bateyes surrounding La Romana. Mothers were ≥18 years and children were between 7 and 14 years. Mothers self-reported perceived stress and demographic factors. Hair samples were collected from mothers and children, and HCC was assessed using enzyme-linked immunosorbent assays. General linear models examined associations between socioeconomic factors and HCC, and between maternal and child HCC. HCC were measured in 88 maternal and 87 child samples (N = 175). Mothers living in a batey had higher HCC than those living in La Romana (p = 0.001). HCC was positively associated among maternal-child dyads (p = 0.001). Further, Haitian-born mothers as a population who frequently live in a rural batey experienced higher HCC (p = 0.025) that may partially be explained by discriminatory practices in the DR. This research helps to elucidate the impact of urban and rural environmental settings on HCC.Lay summaryThis study focuses on chronic stress, measured by hair cortisol levels, among a low-income population of Dominican and Haitian mother-child pairs who live in urban and rural settings. We found that Haitian-born mothers, who frequently live in a rural batey, had higher hair cortisol levels than Dominican born mothers. Hair cortisol levels between mothers and their children were positively associated. This study addresses the impact of urban and rural environments on the stress response among socioeconomically disadvantaged persons living in an upper middle income country who bear an excessive burden of psychosocial stress.


Asunto(s)
Hidrocortisona , Población Rural , República Dominicana , Femenino , Haití , Humanos , Relaciones Madre-Hijo , Madres , Estrés Psicológico
19.
mSphere ; 5(6)2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-33177212

RESUMEN

Pluripotent stem-cell-derived human intestinal organoids (HIOs) are three-dimensional, multicellular structures that model a naive intestinal epithelium in an in vitro system. Several published reports have investigated the use of HIOs to study host-microbe interactions. We recently demonstrated that microinjection of the nonpathogenic Escherichia coli strain ECOR2 into HIOs induced morphological and functional maturation of the HIO epithelium, including increased secretion of mucins and cationic antimicrobial peptides. In the current work, we use ECOR2 as a biological probe to further characterize the environment present in the HIO lumen. We generated an isogenic mutant in the general stress response sigma factor RpoS and employed this mutant to compare challenges faced by a bacterium during colonization of the HIO lumen relative to the germ-free mouse intestine. We demonstrate that the loss of RpoS significantly decreases the ability of ECOR2 to colonize HIOs, although it does not prevent colonization of germ-free mice. These results indicate that the HIO lumen is a more restrictive environment to E. coli than the germ-free mouse intestine, thus increasing our understanding of the HIO model system as it pertains to studying the establishment of intestinal host-microbe symbioses.IMPORTANCE Technological advancements have driven and will continue to drive the adoption of organotypic systems for investigating host-microbe interactions within the human intestinal ecosystem. Using E. coli deficient in the RpoS-mediated general stress response, we demonstrate that the type or severity of microbial stressors within the HIO lumen is more restrictive than those of the in vivo environment of the germ-free mouse gut. This study provides important insight into the nature of the HIO microenvironment from a microbiological standpoint.


Asunto(s)
Escherichia coli/crecimiento & desarrollo , Mucosa Intestinal/citología , Intestinos/citología , Organoides/citología , Células Madre Pluripotentes/citología , Animales , Proteínas Bacterianas/genética , Diferenciación Celular , Células Cultivadas , Escherichia coli/genética , Femenino , Humanos , Técnicas In Vitro , Mucosa Intestinal/microbiología , Intestinos/microbiología , Masculino , Ratones , Organoides/microbiología , Células Madre Pluripotentes/microbiología , Factor sigma/genética
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