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1.
Function (Oxf) ; 4(2): zqac069, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36778746

RESUMEN

We compared endogenous ω-3 PUFA production to supplementation for improving obesity-related metabolic dysfunction. Fat-1 transgenic mice, who endogenously convert exogenous ω-6 to ω-3 PUFA, and wild-type littermates were fed a high-fat diet and a daily dose of either ω-3 or ω-6 PUFA-rich oil for 12 wk. The endogenous ω-3 PUFA production improved glucose intolerance and insulin resistance but not hepatic steatosis. Conversely, ω-3 PUFA supplementation fully prevented hepatic steatosis but failed to improve insulin resistance. Both models increased hepatic levels of ω-3 PUFA-containing 2-monoacylglycerol and N-acylethanolamine congeners, and reduced levels of ω-6 PUFA-derived endocannabinoids with ω-3 PUFA supplementation being more efficacious. Reduced hepatic lipid accumulation associated with the endocannabinoidome metabolites EPEA and DHEA, which was causally demonstrated by lower lipid accumulation in oleic acid-treated hepatic cells treated with these metabolites. While both models induced a significant fecal enrichment of the beneficial Allobaculum genus, mice supplemented with ω-3 PUFA displayed additional changes in the gut microbiota functions with a significant reduction of fecal levels of the proinflammatory molecules lipopolysaccharide and flagellin. Multiple-factor analysis identify that the metabolic improvements induced by ω-3 PUFAs were accompanied by a reduced production of the proinflammatory cytokine TNFα, and that ω-3 PUFA supplementation had a stronger effect on improving the hepatic fatty acid profile than endogenous ω-3 PUFA. While endogenous ω-3 PUFA production preferably improves glucose tolerance and insulin resistance, ω-3 PUFA intake appears to be required to elicit selective changes in hepatic endocannabinoidome signaling that are essential to alleviate high-fat diet-induced hepatic steatosis.


Asunto(s)
Ácidos Grasos Omega-3 , Hígado Graso , Resistencia a la Insulina , Ratones , Animales , Hígado Graso/tratamiento farmacológico , Ratones Transgénicos , Suplementos Dietéticos
2.
Pediatr Dermatol ; 40(1): 129-131, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36385397

RESUMEN

Despite advances in our understanding of the human microbiome, there exist significant knowledge gaps in our understanding of the skin microbiome of the preterm neonate. Herein, we describe skin microbiome sampling of six preterm neonates at multiple timepoints, and compare the skin microbiome samples to environmental (crib/isolette swabs) and negative controls. Samples of the same type (skin, crib, control) were more similar than when compared by week or by patient.


Asunto(s)
Recien Nacido Prematuro , Microbiota , Recién Nacido , Humanos , Piel
3.
Am J Perinatol ; 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35709728

RESUMEN

OBJECTIVE: Enteral feeding tubes are used in neonatal intensive care units (NICUs) to assess feeding tolerance by utilizing preprandial gastric residual aspiration. This study evaluates the effect of gastric residual aspiration on the preterm infant fecal microbiome and gastrointestinal inflammation. STUDY DESIGN: Fifty-one very low birth weight (VLBW) infants (≤32 weeks' gestational age and ≤1,250 g) enrolled in a larger single-center randomized controlled trial evaluating the effects of routine and nonroutine gastric residual aspiration were selected for further analysis. Of those infants, 30 had microbiome analysis performed on stools collected at 6 weeks by sequencing the bacterial V1 to V3 variable regions of the genes encoding for 16S rRNA. In an additional 21 infants, stool samples collected at 3 and 6 weeks were analyzed for intestinal inflammation using a cytokine multiplex panel. RESULTS: Microbial communities between groups were not distinct from each other and there was no difference in intestinal inflammation between groups. Analyses using gene expression packages DESeq2 and edgeR produced statistically significant differences in several taxa, possibly indicating a more commensal intestinal microbiome in infants not undergoing gastric residual aspiration. CONCLUSION: Omission of routine gastric residual aspiration was not associated with intestinal dysbiosis or inflammation, providing additional evidence that monitors preprandial gastric residuals is unnecessary. KEY POINTS: · Omission of routine gastric residual aspiration was not associated with intestinal dysbiosis or inflammation.. · Existing literature indicates preprandial gastric aspiration does not reliably correlate with development of necrotizing enterocolitis but does correlate with delayed enteral nutrition.. · Further study is required but this data that suggest monitoring preprandial gastric residuals are unnecessary..

4.
Science ; 374(6564): 216-224, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34618582

RESUMEN

The microbiota comprises the microorganisms that live in close contact with the host, with mutual benefit for both counterparts. The contribution of the gut microbiota to the emergence of castration-resistant prostate cancer (CRPC) has not yet been addressed. We found that androgen deprivation in mice and humans promotes the expansion of defined commensal microbiota that contributes to the onset of castration resistance in mice. Specifically, the intestinal microbial community in mice and patients with CRPC was enriched for species capable of converting androgen precursors into active androgens. Ablation of the gut microbiota by antibiotic therapy delayed the emergence of castration resistance even in immunodeficient mice. Fecal microbiota transplantation (FMT) from CRPC mice and patients rendered mice harboring prostate cancer resistant to castration. In contrast, tumor growth was controlled by FMT from hormone-sensitive prostate cancer patients and Prevotella stercorea administration. These results reveal that the commensal gut microbiota contributes to endocrine resistance in CRPC by providing an alternative source of androgens.


Asunto(s)
Andrógenos/biosíntesis , Bacterias/metabolismo , Microbioma Gastrointestinal/fisiología , Interacciones Microbiota-Huesped , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/microbiología , Anciano , Anciano de 80 o más Años , Antagonistas de Andrógenos/uso terapéutico , Animales , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/genética , Línea Celular Tumoral , Trasplante de Microbiota Fecal , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad , Neoplasias Experimentales , Prevotella/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Simbiosis , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Gut Microbes ; 13(1): 1-15, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34100340

RESUMEN

To investigate the relationship between intestinal microbiota and SARS-CoV-2-mediated pathogenicity in a United States, majority African American cohort. We prospectively collected fecal samples from 50 SARS-CoV-2 infected patients, 9 SARS-CoV-2 recovered patients, and 34 uninfected subjects seen by the hospital with unrelated respiratory medical conditions (controls). 16S rRNA sequencing and qPCR analysis was performed on fecal DNA/RNA. The fecal microbial composition was found to be significantly different between SARS-CoV-2 patients and controls (PERMANOVA FDR-P = .004), independent of antibiotic exposure. Peptoniphilus, Corynebacterium and Campylobacter were identified as the three most significantly enriched genera in COVID-19 patients compared to controls. Actively infected patients were also found to have a different gut microbiota than recovered patients (PERMANOVA FDR-P = .003), and the most enriched genus in infected patients was Campylobacter, with Agathobacter and Faecalibacterium being enriched in the recovered patients. No difference in microbial community structure between recovered patients and uninfected controls was observed, nor a difference in alpha diversity between the three groups. 24 of the 50 COVID-19 patients (48%) tested positive via RT-qPCR for fecal SARS-CoV-2 RNA. A significant difference in gut microbial composition between SARS-CoV-2 positive and negative samples was observed, with Klebsiella and Agathobacter being enriched in the positive cohort. No significant associations between microbiome composition and disease severity was found. The intestinal microbiota is sensitive to the presence of SARS-CoV-2, with increased relative abundance of genera (Campylobacter, Klebsiella) associated with gastrointestinal (GI) disease. Further studies are needed to investigate the functional impact of SARS-CoV-2 on GI health.


Asunto(s)
COVID-19/microbiología , Microbioma Gastrointestinal , Anciano , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , COVID-19/diagnóstico , COVID-19/virología , Estudios de Cohortes , Heces/microbiología , Heces/virología , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Ribosómico 16S/genética , ARN Viral/genética , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/patogenicidad , Índice de Severidad de la Enfermedad , Estados Unidos/epidemiología
6.
Am J Gastroenterol ; 116(8): 1638-1645, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34047305

RESUMEN

INTRODUCTION: Proton pump inhibitor (PPI) use was recently reported to be associated with increased severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and worse clinical outcomes. The underlying mechanism(s) for this association are unclear. METHODS: We performed a prospective study of hospitalized coronavirus disease 2019 (COVID-19) patients and COVID-negative controls to understand how PPI use may affect angiotensin-converting enzyme 2 (ACE2) expression and stool SARS-CoV-2 RNA. Analysis of a retrospective cohort of hospitalized patients with COVID-19 from March 15, 2020 to August 15, 2020 in 6 hospitals was performed to evaluate the association of PPI use and mortality. Covariates with clinical relevance to COVID-19 outcomes were included to determine predictors of in-hospital mortality. RESULTS: Control PPI users had higher salivary ACE2 mRNA levels than nonusers, 2.39 ± 1.15 vs 1.22 ± 0.92 (P = 0.02), respectively. Salivary ACE2 levels and stool SARS-CoV-2 RNA detection rates were comparable between users and nonusers of PPI. In 694 hospitalized patients with COVID-19 (age = 58 years, 46% men, and 65% black), mortality rate in PPI users and nonusers was 30% (68/227) vs 12.1% (53/439), respectively. Predictors of mortality by logistic regression were PPI use (adjusted odds ratio [aOR] = 2.72, P < 0.001), age (aOR = 1.66 per decade, P < 0.001), race (aOR = 3.03, P = 0.002), cancer (aOR = 2.22, P = 0.008), and diabetes (aOR = 1.95, P = 0.003). The PPI-associated mortality risk was higher in black patients (aOR = 4.16, 95% confidence interval: 2.28-7.59) than others (aOR = 1.62, 95% confidence interval: 0.82-3.19, P = 0.04 for interaction). DISCUSSION: COVID-negative PPI users had higher salivary ACE2 expression. PPI use was associated with increased mortality risk in patients with COVID-19, particularly African Americans.


Asunto(s)
Enzima Convertidora de Angiotensina 2/sangre , COVID-19/sangre , COVID-19/mortalidad , Inhibidores de la Bomba de Protones/efectos adversos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Medición de Riesgo
7.
J Med Internet Res ; 22(8): e16175, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-32773380

RESUMEN

BACKGROUND: A clinical algorithm (Algo) in paper form is used in Quebec, Canada, to allow health care workers other than occupational therapists (OTs) to make bathroom adaptation recommendations for older adults. An integrated knowledge transfer process around Algo suggested an electronic version of this decision support system (electronic decision support system [e-DSS]) to be used by older adults and their caregivers in search of information and solutions for their autonomy and safety in the bathroom. OBJECTIVE: This study aims to (1) create an e-DSS for the self-selection of bathroom-assistive technology by community-dwelling older adults and their caregivers and (2) assess usability with lay users and experts to improve the design accordingly. METHODS: On the basis of a user-centered design approach, the process started with content identification for the prototype through 7 semistructured interviews with key informants of various backgrounds (health care providers, assistive technology providers, and community services) and 4 focus groups (2 with older adults and 2 with caregivers). A thematic content transcript analysis was carried out and used during the creation of the prototype. The prototype was refined iteratively using think-aloud and observation methods with a clinical expert (n=1), researchers (n=3), OTs (n=3), older adults (n=3), and caregivers (n=3), who provided information on the usability of the e-DSS. RESULTS: Overall, 4 themes served as the criteria for the prototype of the electronic Algo (Hygiene 2.0 [H2.0]): focus (safety, confidentiality, well-being, and autonomy), engage, facilitate (simplify, clarify, and illustrate), and access. For example, users first pay attention to the images (engage and illustrate) that can be used to depict safe postures (safety), illustrate questions embedded in the decision support tool (clarify and illustrate), and demonstrate the context of the use of assistive technology (safety and clarify). CONCLUSIONS: The user-centered design of H2.0 allowed the cocreation of an e-DSS in the form of a website, in line with the needs of community-dwelling older adults and their caregivers seeking bathroom-assistive technology that enables personal hygiene. Each iteration improved usability and brought more insight into the users' realities, tailoring the e-DSS to the implementation context.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas/normas , Dispositivos de Autoayuda/normas , Cuartos de Baño/normas , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Biol Blood Marrow Transplant ; 26(11): 2001-2010, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32717434

RESUMEN

Infection is a major cause of morbidity and mortality after hematopoietic cell transplantation (HCT). Gut microbiota (GM) composition and metabolites provide colonization resistance against dominance of potential pathogens, and GM dysbiosis following HCT can be deleterious to immune reconstitution. Little is known about the composition, diversity, and evolution of GM communities in HCT patients and their association with subsequent febrile neutropenia (FN) and infection. Identification of markers before HCT that predict subsequent infection could be useful in developing individualized antimicrobial strategies. Fecal samples were collected prospectively from 33 HCT recipients at serial time points: baseline, post-conditioning regimen, neutropenia onset, FN onset (if present), and hematologic recovery. GM was assessed by 16S rRNA sequencing. FN and major infections (ie, bloodstream infection, typhlitis, invasive fungal infection, pneumonia, and Clostridium difficile enterocolitis) were identified. Significant shifts in GM composition and diversity were observed during HCT, with the largest alterations occurring after initiation of antibiotics. Loss of diversity persisted without a return to baseline at hematologic recovery. GM in patients with FN was enriched in Mogibacterium, Bacteroides fragilis, and Parabacteroides distasonis, whereas increased abundance of Prevotella, Ruminococcus, Dorea, Blautia, and Collinsella was observed in patients without fever. A baseline protective GM profile (BPGMP) was predictive of protection from major infection. The BPGMP was associated with subsequent major infections with 77% accuracy and an area under the curve of 79%, with sensitivity, specificity, and positive and negative predictive values of 0.71, 0.91, 0.77, and 0.87, respectively. Our data show that large shifts in GM composition occur early after HCT, and differences in baseline GM composition are associated with the development of subsequent major infections.


Asunto(s)
Microbioma Gastrointestinal , Trasplante de Células Madre Hematopoyéticas , Bacteroidetes , Heces , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , ARN Ribosómico 16S/genética
9.
mSystems ; 5(1)2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31937674

RESUMEN

Disrupted interactions between host and intestinal bacteria are implicated in colorectal cancer (CRC) development. However, activities derived from these bacteria and their interplay with the host are unclear. Here, we examine this interplay by performing mouse and microbiota RNA sequencing on colon tissues and 16S and small RNA sequencing on stools from germfree (GF) and gnotobiotic ApcMin Δ 850/+ ;Il10-/- mice associated with microbes from biofilm-positive human CRC tumor (BF+T) and biofilm-negative healthy (BF-bx) tissues. The bacteria in BF+T mice differentially expressed (DE) >2,900 genes, including genes related to bacterial secretion, virulence, and biofilms but affected only 62 host genes. Small RNA sequencing of stools from these cohorts revealed eight significant DE host microRNAs (miRNAs) based on biofilm status and several miRNAs that correlated with bacterial taxon abundances. Additionally, computational predictions suggest that some miRNAs preferentially target bacterial genes while others primarily target mouse genes. 16S rRNA sequencing of mice that were reassociated with mucosa-associated communities from the initial association revealed a set of 13 bacterial genera associated with cancer that were maintained regardless of whether the reassociation inoculums were initially obtained from murine proximal or distal colon tissues. Our findings suggest that complex interactions within bacterial communities affect host-derived miRNA, bacterial composition, and CRC development.IMPORTANCE Bacteria and bacterial biofilms have been implicated in colorectal cancer (CRC), but it is still unclear what genes these microbial communities express and how they influence the host. MicroRNAs regulate host gene expression and have been explored as potential biomarkers for CRC. An emerging area of research is the ability of microRNAs to impact growth and gene expression of members of the intestinal microbiota. This study examined the bacteria and bacterial transcriptome associated with microbes derived from biofilm-positive human cancers that promoted tumorigenesis in a murine model of CRC. The murine response to different microbial communities (derived from CRC patients or healthy people) was evaluated through RNA and microRNA sequencing. We identified a complex interplay between biofilm-associated bacteria and the host during CRC in mice. These findings may lead to the development of new biomarkers and therapeutics for identifying and treating biofilm-associated CRCs.

10.
J Clin Invest ; 129(4): 1699-1712, 2019 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-30855275

RESUMEN

Mucus-invasive bacterial biofilms are identified on the colon mucosa of approximately 50% of colorectal cancer (CRC) patients and approximately 13% of healthy subjects. Here, we test the hypothesis that human colon biofilms comprise microbial communities that are carcinogenic in CRC mouse models. Homogenates of human biofilm-positive colon mucosa were prepared from tumor patients (tumor and paired normal tissues from surgical resections) or biofilm-positive biopsies from healthy individuals undergoing screening colonoscopy; homogenates of biofilm-negative colon biopsies from healthy individuals undergoing screening colonoscopy served as controls. After 12 weeks, biofilm-positive, but not biofilm-negative, human colon mucosal homogenates induced colon tumor formation in 3 mouse colon tumor models (germ-free ApcMinΔ850/+;Il10-/- or ApcMinΔ850/+ and specific pathogen-free ApcMinΔ716/+ mice). Remarkably, biofilm-positive communities from healthy colonoscopy biopsies induced colon inflammation and tumors similarly to biofilm-positive tumor tissues. By 1 week, biofilm-positive human tumor homogenates, but not healthy biopsies, displayed consistent bacterial mucus invasion and biofilm formation in mouse colons. 16S rRNA gene sequencing and RNA-Seq analyses identified compositional and functional microbiota differences between mice colonized with biofilm-positive and biofilm-negative communities. These results suggest human colon mucosal biofilms, whether from tumor hosts or healthy individuals undergoing screening colonoscopy, are carcinogenic in murine models of CRC.


Asunto(s)
Biopelículas , Carcinogénesis , Colon/microbiología , Neoplasias del Colon/microbiología , Microbioma Gastrointestinal , Neoplasias Experimentales/microbiología , Animales , Colon/metabolismo , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Humanos , Ratones , Ratones Noqueados , Neoplasias Experimentales/genética , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología
11.
Gut Microbes ; 10(3): 289-297, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30404568

RESUMEN

The purpose of this prospective cross-sectional cohort pilot study is to explore the initial microbial community of gastric aspirate fluid as collected immediately after birth and its relationships with mode of delivery and preterm birth. Twenty-nine gastric aspirate samples collected immediately after birth from infants born between 24-40 weeks gestation were analyzed for microbial composition. Total microbial content was low in many samples, with a substantial number sharing taxonomic composition with negative controls. qPCR targeting the 16S rRNA gene showed that infants delivered vaginally had a higher microbial load than infants delivered by C-section. Some pre-term samples showed high relative abundance of genus Ureaplasma, consistent with previous literature that has implicated infections with this taxon as a potential cause of pre-term birth. Vaginally born term infant samples, by contrast, had significantly higher levels of genus Lactobacillus with Lactobacillus crispatus the most dominant species. Microbial evaluation showed that vaginally born term infant gastric aspirate samples had higher levels of lactobacilli than pre-terms. Samples from many infants had low microbial load near the edge of the detection limit.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Biodiversidad , Microbioma Gastrointestinal , Estómago/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Carga Bacteriana , Estudios de Cohortes , Estudios Transversales , Femenino , Lavado Gástrico , Microbioma Gastrointestinal/genética , Edad Gestacional , Humanos , Recién Nacido , Masculino , Proyectos Piloto , ARN Ribosómico 16S/genética
12.
Carcinogenesis ; 39(8): 1068-1078, 2018 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-29846515

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in the United States yet data are scant regarding host factors influencing pancreatic carcinogenesis. Increasing evidence support the role of the host microbiota in carcinogenesis but its role in PDAC is not well established. Herein, we report that antibiotic-mediated microbial depletion of KrasG12D/PTENlox/+ mice showed a decreased proportion of poorly differentiated tumors compared to microbiota-intact KrasG12D/PTENlox/+ mice. Subsequent 16S rRNA PCR showed that ~50% of KrasG12D/PTENlox/+ mice with PDAC harbored intrapancreatic bacteria. To determine if a similar observation in humans correlates with presence of PDAC, benign and malignant human pancreatic surgical specimens demonstrated a microbiota by 16S bacterial sequencing and culture confirmation. However, the microbial composition did not differentiate PDAC from non-PDAC tissue. Furthermore, murine pancreas did not naturally acquire a pancreatic microbiota, as germ-free mice transferred to specific pathogen-free housing failed to acquire intrapancreatic bacteria over time, which was not augmented by a murine model of colitis. Finally, antibiotic-mediated microbial depletion of Nod-SCID mice, compared to microbiota-intact, showed increased time to PDAC xenograft formation, smaller tumors, and attenuated growth. Interestingly, both xenograft cohorts were devoid of intratumoral bacteria by 16S rRNA PCR, suggesting that intrapancreatic/intratumoral microbiota is not the sole driver of PDAC acceleration. Xenografts from microbiota-intact mice demonstrated innate immune suppression by immunohistochemistry and differential regulation of oncogenic pathways as determined by RNA sequencing. Our work supports a long-distance role of the intestinal microbiota on PDAC progression and opens new research avenues regarding pancreatic carcinogenesis.


Asunto(s)
Carcinogénesis/inmunología , Carcinoma Ductal Pancreático/inmunología , Microbioma Gastrointestinal/inmunología , Interacciones Microbiota-Huesped/inmunología , Neoplasias Pancreáticas/inmunología , Adulto , Anciano , Animales , Antibacterianos/administración & dosificación , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/aislamiento & purificación , Carcinogénesis/efectos de los fármacos , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Línea Celular Tumoral , Progresión de la Enfermedad , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Vida Libre de Gérmenes , Interacciones Microbiota-Huesped/efectos de los fármacos , Humanos , Intestinos/microbiología , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Ratones Transgénicos , Persona de Mediana Edad , Páncreas/microbiología , Páncreas/patología , Páncreas/cirugía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , ARN Ribosómico 16S/aislamiento & purificación , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Gastroenterology ; 154(6): 1751-1763.e2, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29408609

RESUMEN

BACKGROUND & AIMS: Campylobacter jejuni, a prevalent foodborne bacterial pathogen, exploits the host innate response to induce colitis. Little is known about the roles of microbiota in C jejuni-induced intestinal inflammation. We investigated interactions between microbiota and intestinal cells during C jejuni infection of mice. METHODS: Germ-free C57BL/6 Il10-/- mice were colonized with conventional microbiota and infected with a single dose of C jejuni (109 colony-forming units/mouse) via gavage. Conventional microbiota were cultured under aerobic, microaerobic, or anaerobic conditions and orally transplanted into germ-free Il10-/- mice. Colon tissues were collected from mice and analyzed by histology, real-time polymerase chain reaction, and immunoblotting. Fecal microbiota and bile acids were analyzed with 16S sequencing and high-performance liquid chromatography with mass spectrometry, respectively. RESULTS: Introduction of conventional microbiota reduced C jejuni-induced colitis in previously germ-free Il10-/- mice, independent of fecal load of C jejuni, accompanied by reduced activation of mammalian target of rapamycin. Microbiota transplantation and 16S ribosomal DNA sequencing experiments showed that Clostridium XI, Bifidobacterium, and Lactobacillus were enriched in fecal samples from mice colonized with microbiota cultured in anaerobic conditions (which reduce colitis) compared with mice fed microbiota cultured under aerobic conditions (susceptible to colitis). Oral administration to mice of microbiota-derived secondary bile acid sodium deoxycholate, but not ursodeoxycholic acid or lithocholic acid, reduced C jejuni-induced colitis. Depletion of secondary bile acid-producing bacteria with antibiotics that kill anaerobic bacteria (clindamycin) promoted C jejuni-induced colitis in specific pathogen-free Il10-/- mice compared with the nonspecific antibiotic nalidixic acid; colitis induction by antibiotics was associated with reduced level of luminal deoxycholate. CONCLUSIONS: We identified a mechanism by which the microbiota controls susceptibility to C jejuni infection in mice, via bacteria-derived secondary bile acids.


Asunto(s)
Ácidos y Sales Biliares/administración & dosificación , Infecciones por Campylobacter/microbiología , Campylobacter jejuni/metabolismo , Gastroenteritis/microbiología , Microbioma Gastrointestinal/fisiología , Anaerobiosis , Animales , Colagogos y Coleréticos/administración & dosificación , Colon/microbiología , Técnicas de Cultivo/métodos , Ácido Desoxicólico/administración & dosificación , Modelos Animales de Enfermedad , Trasplante de Microbiota Fecal , Heces/microbiología , Intestinos/citología , Ácido Litocólico/administración & dosificación , Ratones , Ratones Endogámicos C57BL , Ácido Ursodesoxicólico/administración & dosificación
14.
Cancer Res ; 77(10): 2620-2632, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28416491

RESUMEN

Inflammation and microbiota are critical components of intestinal tumorigenesis. To dissect how the microbiota contributes to tumor distribution, we generated germ-free (GF) ApcMin/+ and ApcMin/+ ;Il10-/- mice and exposed them to specific-pathogen-free (SPF) or colorectal cancer-associated bacteria. We found that colon tumorigenesis significantly correlated with inflammation in SPF-housed ApcMin/+ ;Il10-/- , but not in ApcMin/+ mice. In contrast, small intestinal neoplasia development significantly correlated with age in both ApcMin/+ ;Il10-/- and ApcMin/+ mice. GF ApcMin/+ ;Il10-/- mice conventionalized by an SPF microbiota had significantly more colon tumors compared with GF mice. Gnotobiotic studies revealed that while Fusobacterium nucleatum clinical isolates with FadA and Fap2 adhesins failed to induce inflammation and tumorigenesis, pks+Escherichia coli promoted tumorigenesis in the ApcMin/+ ;Il10-/- model in a colibactin-dependent manner, suggesting colibactin is a driver of carcinogenesis. Our results suggest a distinct etiology of cancers in different locations of the gut, where colon cancer is primarily driven by inflammation and the microbiome, while age is a driving force for small intestine cancer. Cancer Res; 77(10); 2620-32. ©2017 AACR.


Asunto(s)
Transformación Celular Neoplásica , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/patología , Microbioma Gastrointestinal , Proteína de la Poliposis Adenomatosa del Colon/deficiencia , Animales , Bacterias/clasificación , Bacterias/genética , Modelos Animales de Enfermedad , Inflamación/complicaciones , Inflamación/patología , Interleucina-10/deficiencia , Ratones , Ratones Noqueados , Ratones Transgénicos
15.
CMAJ Open ; 4(3): E398-E403, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27730103

RESUMEN

BACKGROUND: Evidence-based indicators of quality of care have been developed to improve care and performance in Canadian emergency departments. The feasibility of measuring these indicators has been assessed mainly in urban and academic emergency departments. We sought to assess the feasibility of measuring quality-of-care indicators in rural emergency departments in Quebec. METHODS: We previously identified rural emergency departments in Quebec that offered medical coverage with hospital beds 24 hours a day, 7 days a week and were located in rural areas or small towns as defined by Statistics Canada. A standardized protocol was sent to each emergency department to collect data on 27 validated quality-of-care indicators in 8 categories: duration of stay, patient safety, pain management, pediatrics, cardiology, respiratory care, stroke and sepsis/infection. Data were collected by local professional medical archivists between June and December 2013. RESULTS: Fifteen (58%) of the 26 emergency departments invited to participate completed data collection. The ability to measure the 27 quality-of-care indicators with the use of databases varied across departments. Centres 2, 5, 6 and 13 used databases for at least 21 of the indicators (78%-92%), whereas centres 3, 8, 9, 11, 12 and 15 used databases for 5 (18%) or fewer of the indicators. On average, the centres were able to measure only 41% of the indicators using heterogeneous databases and manual extraction. The 15 centres collected data from 15 different databases or combinations of databases. The average data collection time for each quality-of-care indicator varied from 5 to 88.5 minutes. The median data collection time was 15 minutes or less for most indicators. INTERPRETATION: Quality-of-care indicators were not easily captured with the use of existing databases in rural emergency departments in Quebec. Further work is warranted to improve standardized measurement of these indicators in rural emergency departments in the province and to generalize the information gathered in this study to other health care environments.

16.
BMC Health Serv Res ; 15: 572, 2015 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-26700302

RESUMEN

BACKGROUND: Rural emergency departments (EDs) constitute crucial safety nets for the 20% of Canadians who live in rural areas. Pilot data suggests that the province of Québec appears to provide more comprehensive access to services than do other provinces. A difference that may be attributable to provincial policy/guidelines "the provincial ED management Guide". The aim of this study was to provide a detailed description of rural EDs in Québec and utilization of the provincial ED management Guide. METHODS: We selected EDs offering 24/7 medical coverage, with hospitalization beds, located in rural or small towns. We collected data via telephone, paper, and online surveys with rural ED/hospital staff. Data were also collected from Québec's Ministry of Health databases and from Statistics Canada. We computed descriptive statistics, ANOVA and t-tests were used to examine the relationship between ED census, services and inter-facility transfer requirements. RESULTS: A total of 23 of Québec's 26 rural EDs (88%) consented to participate in the study. The mean annual ED visits was 18 813 (Standard Deviation = 6 151). Thirty one percent of ED physicians were recent graduates with fewer than 5 years of experience. Only 6 % had residency training or certification in emergency medicine. Teams have good local access (24/7) to diagnostic equipment such as CT scanner (74%), intensive unit care (78%) and general surgical services (78%), but limited access to other consultants. Sixty one percent of participants have reported good knowledge of the provincial ED management Guide, but only 23% of them have used the guidelines. Furthermore, more than 40% of EDs were more than 300 km from levels 1 to 2 trauma centers, and only 30% had air transport access. CONCLUSIONS: Rural EDs in Québec are staffed by relatively new graduates working as solo physicians in well-resourced and moderately busy (by rural standards) EDs. The provincial ED management Guide may have contributed to this model of service attribution. However, the majority of rural ED staff report limited knowledge or use of the provincial ED management Guide and increased efforts at disseminating this Guide are warranted.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Análisis de Varianza , Certificación , Competencia Clínica/normas , Estudios Transversales , Manejo de la Enfermedad , Medicina de Emergencia/normas , Medicina de Emergencia/estadística & datos numéricos , Adhesión a Directriz , Conocimientos, Actitudes y Práctica en Salud , Accesibilidad a los Servicios de Salud/normas , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Hospitales Rurales/estadística & datos numéricos , Humanos , Internado y Residencia/normas , Internado y Residencia/estadística & datos numéricos , Tiempo de Internación , Médicos/normas , Médicos/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Quebec , Servicios de Salud Rural/estadística & datos numéricos , Encuestas y Cuestionarios , Tiempo de Tratamiento
17.
PLoS One ; 10(11): e0142826, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26554831

RESUMEN

The pharmacological effect of opioids originates, at the cellular level, by their interaction with the µ-opioid receptor (mOR) resulting in the regulation of voltage-gated Ca2+ channels and inwardly rectifying K+ channels that ultimately modulate the synaptic transmission. Recently, an alternative six trans-membrane helix isoform of mOR, (6TM-mOR) has been identified, but its function and signaling are still largely unknown. Here, we present the structural and functional mechanisms of 6TM-mOR signaling activity upon binding to morphine. Our data suggest that despite the similarity of binding modes of the alternative 6TM-mOR and the dominant seven trans-membrane helix variant (7TM-mOR), the interaction with morphine generates different dynamic responses in the two receptors, thus, promoting the activation of different mOR-specific signaling pathways. We characterize a series of 6TM-mOR-specific cellular responses, and observed that they are significantly different from those for 7TM-mOR. Morphine stimulation of 6TM-mOR does not promote a cellular cAMP response, while it increases the intracellular Ca2+ concentration and reduces the cellular K+ conductance. Our findings indicate that 6TM-mOR has a unique contribution to the cellular opioid responses. Therefore, it should be considered as a relevant target for the development of novel pharmacological tools and medical protocols involving the use of opioids.


Asunto(s)
Analgésicos Opioides/farmacología , Morfina/farmacología , Isoformas de Proteínas/metabolismo , Receptores Opioides mu/metabolismo , Transducción de Señal/efectos de los fármacos , Humanos , Modelos Moleculares , Conformación Proteica
18.
J Pain ; 16(12): 1321-1333, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26456674

RESUMEN

UNLABELLED: Recent efforts have suggested that the ß-adrenergic receptor (ß-AR) system may be a novel and viable therapeutic target for pain reduction; however, most of the work to date has focused on the ß(2)-adrenergic receptor (AR). Here, we compared the antinociceptive effects of enantiomeric configurations of propranolol and bupranolol, two structurally similar nonselective ß-blocking drugs, against mouse models of inflammatory and chronic pain. In addition, we calculated in silico docking and measured the binding properties of propranolol and bupranolol for all 3 ß-ARs. Of the agents examined, S-bupranolol is superior in terms of its antinociceptive effect and exhibited fewer side effects than propranolol or its associated enantiomers. In contrast to propranolol, S-bupranolol exhibited negligible ß-AR intrinsic agonist activity and displayed a full competitive antagonist profile at ß(1)/ß(2)/ß(3)-ARs, producing a unique blockade of ß(3)-ARs. We have shown that S-bupranolol is an effective antinociceptive agent in mice without negative side effects. The distinctive profile of S-bupranolol is most likely mediated by its negligible ß-AR intrinsic agonist activity and unique blockade of ß(3)-AR. These findings suggest that S-bupranolol instead of propranolol may represent a new and effective treatment for a variety of painful conditions. PERSPECTIVE: The S enantiomer of bupranolol, a ß-receptor antagonist, shows greater antinociceptive efficacy and a superior preclinical safety profile and it should be considered as a unique ß-adrenergic receptor compound to advance future clinical pain studies.


Asunto(s)
Antagonistas Adrenérgicos beta/farmacología , Analgésicos/farmacología , Bupranolol/farmacología , Nocicepción/efectos de los fármacos , Propranolol/farmacología , Receptores Adrenérgicos beta/metabolismo , Antagonistas Adrenérgicos beta/química , Analgésicos/química , Animales , Bupranolol/química , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Dimensión del Dolor , Propranolol/química , Receptores Adrenérgicos beta/química , Estereoisomerismo
19.
BMC Res Notes ; 8: 571, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26471509

RESUMEN

BACKGROUND: Seven chronic disease prevention and management programs were implemented across Quebec with funding support from a provincial-private industry funding initiative. Given the complexity of implementing integrated primary care chronic disease management programs, a knowledge transfer meeting was held to share experiences across programs and synthesize common challenges and success factors for implementation. METHODS: The knowledge translation meeting was held in February 2014 in Montreal, Canada. Seventy-five participants consisting of 15 clinicians, 14 researchers, 31 knowledge users, and 15 representatives from the funding agencies were broken up into groups of 10 or 11 and conducted a strengths, weaknesses, opportunities, and threats analysis on either the implementation or the evaluation of these chronic disease management programs. Results were reported back to the larger group during a plenary and recorded. Audiotapes were transcribed and summarized using pragmatic thematic analysis. RESULTS AND DISCUSSION: Strengths to leverage for the implementation of the seven programs include: (1) synergy between clinical and research teams; (2) stakeholders working together; (3) motivation of clinicians; and (4) the fact that the programs are evidence-based. Weaknesses to address include: (1) insufficient resources; (2) organizational change within the clinical sites; (3) lack of referrals from primary care physicians; and (4) lack of access to programs. Strengths to leverage for the evaluation of these programs include: (1) engagement of stakeholders and (2) sharing of knowledge between clinical sites. Weaknesses to address include: (1) lack of referrals; (2) difficulties with data collection; and (3) difficulties in identifying indicators and control groups. Opportunities for both themes include: (1) fostering new and existing partnerships and stakeholder relations; (2) seizing funding opportunities; (3) knowledge transfer; (4) supporting the transformation of professional roles; (5) expand the use of health information technology; and (6) conduct cost evaluations. Fifteen recommendations related to mobilisation of primary care physicians, support for the transformation of professional roles, and strategies aimed at facilitating the implementation and evaluation of chronic disease management programs were formulated based on the discussions at this knowledge translation event. CONCLUSION: The results from this knowledge translation day will help inform the sustainability of these seven chronic disease management programs in Quebec and the implementation and evaluation of similar programs elsewhere.


Asunto(s)
Enfermedad Crónica/prevención & control , Atención a la Salud/organización & administración , Manejo de la Enfermedad , Investigación sobre Servicios de Salud/organización & administración , Desarrollo de Programa/economía , Investigación Biomédica Traslacional/organización & administración , Recolección de Datos , Conocimientos, Actitudes y Práctica en Salud , Financiación de la Atención de la Salud , Humanos , Atención Primaria de Salud , Asociación entre el Sector Público-Privado/organización & administración , Quebec
20.
Pain ; 156(10): 2072-2083, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26207649

RESUMEN

Catechol-O-methyltransferase (COMT) metabolizes catecholaminergic neurotransmitters. Numerous studies have linked COMT to pivotal brain functions such as mood, cognition, response to stress, and pain. Both nociception and risk of clinical pain have been associated with COMT genetic variants, and this association was shown to be mediated through adrenergic pathways. Here, we show that association studies between COMT polymorphic markers and pain phenotypes in 2 independent cohorts identified a functional marker, rs165774, situated in the 3' untranslated region of a newfound splice variant, (a)-COMT. Sequence comparisons showed that the (a)-COMT transcript is highly conserved in primates, and deep sequencing data demonstrated that (a)-COMT is expressed across several human tissues, including the brain. In silico analyses showed that the (a)-COMT enzyme features a distinct C-terminus structure, capable of stabilizing substrates in its active site. In vitro experiments demonstrated not only that (a)-COMT is catalytically active but also that it displays unique substrate specificity, exhibiting enzymatic activity with dopamine but not epinephrine. They also established that the pain-protective A allele of rs165774 coincides with lower COMT activity, suggesting contribution to decreased pain sensitivity through increased dopaminergic rather than decreased adrenergic tone, characteristic of reference isoforms. Our results provide evidence for an essential role of the (a)-COMT isoform in nociceptive signaling and suggest that genetic variations in (a)-COMT isoforms may contribute to individual variability in pain phenotypes.


Asunto(s)
Catecol O-Metiltransferasa/genética , Regulación de la Expresión Génica/genética , Umbral del Dolor/fisiología , Polimorfismo de Nucleótido Simple/genética , Trastornos de la Articulación Temporomandibular/genética , Encéfalo/metabolismo , Estudios de Casos y Controles , Catecol O-Metiltransferasa/metabolismo , Línea Celular Tumoral , Estudios de Cohortes , Femenino , Variación Genética , Humanos , Masculino , Neuroblastoma/patología , Dolor/etiología , Dolor/genética , Fenotipo , ARN Mensajero/metabolismo , Trastornos de la Articulación Temporomandibular/complicaciones , Transfección
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