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1.
Sci Rep ; 14(1): 10783, 2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734725

RESUMO

Necrotising enterocolitis (NEC) has a complex pathophysiology but the common end-point is ischaemia reperfusion injury (IRI) and intestinal necrosis. We have previously reported that RIC significantly reduces the intestinal injury in a rat model of NEC. Here we describe the changes in intestinal mRNA occurring in the intestine of animals exposed to IRI, both with and without RIC. Related rat-pups were randomly assigned to four groups: SHAM, IRI only, RIC only and RIC + IRI. IRI animals, underwent 40 min of intestinal ischaemia, and 90 min of reperfusion. Animals that underwent RIC had three cycles of 5 min of alternating ischaemia/reperfusion by means of a ligature applied to the hind limb. Samples from the terminal ileum were immediately stored in RNA-preserving media for later next generation sequencing and transciptome analysis using R v 3.6.1. Differential expression testing showed that 868 genes differentially expressed in animals exposed to RIC alone compared to SHAM and 135 in the IRI and RIC group compared to IRI alone. Comparison between these two sets showed that 25 genes were differentially expressed in both groups. Pro-inflammatory molecules: NF-ĸß2, Cxcl1, SOD2 and Map3k8 all show reduced expression in response to RIC. Targeted gene analysis revealed increased expression in PI3K which is part of the so-called RISK-pathway which is a key part of the protective mechanisms of RIC in the heart. Overall, this transcriptomic analysis shows that RIC provides a protective effect to the intestine via anti-inflammatory pathways. This could be particularly relevant to treating and preventing NEC.


Assuntos
Modelos Animais de Doenças , Enterocolite Necrosante , Perfilação da Expressão Gênica , Traumatismo por Reperfusão , Animais , Enterocolite Necrosante/genética , Enterocolite Necrosante/patologia , Enterocolite Necrosante/metabolismo , Ratos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Precondicionamento Isquêmico/métodos , Transcriptoma
2.
BMC Med ; 22(1): 3, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38191406

RESUMO

BACKGROUND: Health care routinely fails Indigenous peoples and anti-Indigenous racism is common in clinical encounters. Clinical training programs aimed to enhance Indigenous cultural safety (ICS) rely on learner reported impact assessment even though clinician self-assessment is poorly correlated with observational or patient outcome reporting. We aimed to compare the clinical impacts of intensive and brief ICS training to control, and to assess the feasibility of ICS training evaluation tools, including unannounced Indigenous standardized patient (UISP) visits. METHOD: Using a prospective parallel group three-arm randomized controlled trial design and masked standardized patients, we compared the clinical impacts of the intensive interactive, professionally facilitated, 8- to10-h Sanyas ICS training; a brief 1-h anti-bias training adapted to address anti-Indigenous bias; and control continuing medical education time-attention matched to the intensive training. Participants included 58 non-Indigenous staff physicians, resident physicians and nurse practitioners from family practice clinics, and one emergency department across four teaching hospitals in Toronto, Canada. Main outcome measures were the quality of care provided during UISP visits including adjusted odds that clinician would be recommended by the UISP to a friend or family member; mean item scores on patient experience of care measure; and clinical practice guideline adherence for NSAID renewal and pain assessment. RESULTS: Clinicians in the intensive or brief ICS groups had higher adjusted odds of being highly recommended to friends and family by standardized patients (OR 6.88, 95% CI 1.17 to 40.45 and OR 7.78, 95% CI 1.05 to 58.03, respectively). Adjusted mean item patient experience scores were 46% (95% CI 12% to 80%) and 40% (95% CI 2% to 78%) higher for clinicians enrolled in the intensive and brief training programs, respectively, compared to control. Small sample size precluded detection of training impacts on clinical practice guideline adherence; 100% of UISP visits were undetected by participating clinicians. CONCLUSIONS: Patient-oriented evaluation design and tools including UISPs were demonstrated as feasible and effective. Results show potential impact of cultural safety training on patient recommendation of clinician and improved patient experience. A larger trial to further ascertain impact on clinical practice is needed. TRIAL REGISTRATION: Clinicaltrials.org NCT05890144. Retrospectively registered on June 5, 2023.


Assuntos
Anti-Inflamatórios não Esteroides , Serviço Hospitalar de Emergência , Humanos , Estudos Prospectivos , Canadá , Família
3.
J Pediatr Surg ; 58(7): 1389-1398, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36621342

RESUMO

OBJECTIVE: Remote ischaemic conditioning (RIC) has been shown to reduce ischaemia-reperfusion injury(IRI) in multiple organ systems. IRI is seen in multiple bowel pathologies in the newborn, including NEC. We investigated the potential of RIC as a novel therapy for various intestinal pathologies in the newborn. METHODS: We used an established intestinal IRI model in rat pups which results in similar intestinal injury to necrotising enterocolitis (NEC). Animals were randomly allocated to IRI only(n = 14), IRI + RIC(n = 13) or sham laparotomy(n = 10). The macroscopic extent of intestinal injury is reported as a percentage of total small bowel. Injury severity was measured using Chiu-Park scoring. Neutrophil infiltration/activation was assayed by myeloperoxidase activity. Immunohistochemistry was used to assess the expression of hypoxia-inducible factor alpha (HIF-1α). Data are median (interquartile range). RESULTS: Animals that underwent RIC showed a decreased extent of macroscopic injury from 100%(85-100%) in the IRI only group to 58%(15-84%, p = 0.003) in the IRI + RIC group. Microscopic injury score was significantly lower in animals that underwent RIC compared to IRI alone (3.5[1.25-5] vs 5.5[4-6], p = 0.014). Intestinal myeloperoxidase activity in animals exposed to IRI was 3.4 mU/mg of tissue (2.5-3.7) and 2.1 mU/mg(1.5-2.8) in the IRI + RIC group(p = 0.047). HIF-1α expression showed a non-significant trend towards reduced expression in the IRI + RIC group. CONCLUSIONS: RIC reduces the extent and severity of bowel injury in this animal model, supporting the hypothesis that RIC has therapeutic potential for intestinal diseases in the newborn.


Assuntos
Precondicionamento Isquêmico , Traumatismo por Reperfusão , Ratos , Animais , Animais Recém-Nascidos , Peroxidase , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão/prevenção & controle , Isquemia
4.
ICES J Mar Sci ; 78(1): 305-314, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814897

RESUMO

Biological collections are fundamental to marine scientific research and understanding of biodiversity at various scales. Despite their key importance, sample collections and the institutes that house them are often underfunded and receive comparatively little attention in the discussions associated with global biodiversity agreements. Furthermore, access to collections can be limited by inadequate systems, infrastructure, and networks. With negotiations underway for a new implementing agreement on biodiversity beyond national jurisdiction, marine genetic resources (MGR), including questions on the sharing of benefits, remains the most debated and contentious element. Disparities remain between States regarding access to and utilization of marine biological samples (including MGR) from areas beyond national jurisdiction. Addressing capacity gaps related to collections could provide a point of agreement during negotiations and enhance global inclusivity in access to and utilization of MGR. Here, we examine both existing capacity and regional gaps in marine collections. We propose the strengthening of a distributed network of marine biological collections, building on existing initiatives and emphasizing best practices to bridge regional gaps. Our recommendations include: promoting scientific best practice for the curation of collections; alignment with ocean observing, and sampling initiatives; a potential pairing scheme for collections in developing and developed States; raising awareness of collections and benefits to marine science including through a global registry/directory; and promoting sustainable funding mechanisms to support collections and sustain global generation of contributors and users.

5.
Inflamm Bowel Dis ; 27(10): 1641-1652, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-33570153

RESUMO

BACKGROUND: Intestinal macrophages are key immune cells in the maintenance of intestinal immune homeostasis and have a role in the pathogenesis of inflammatory bowel disease (IBD). However, the mechanisms by which macrophages exert a pathological influence in both ulcerative colitis (UC) and Crohn disease (CD) are not yet well understood. METHODS: We purified intestinal macrophages from gastrointestinal mucosal biopsies (patients with UC, patients with CD, and healthy donors) and analyzed their transcriptome by RNA sequencing and bioinformatics, confirming results with quantitative polymerase chain reaction and immunohistochemistry. RESULTS: Compared with those of healthy donors, intestinal macrophages in patients with UC and with CD showed cellular reprograming of 1287 and 840 dysregulated genes, respectively (false discovery rate ≤ 0.1). The UC and CD intestinal macrophages showed an activated M1 inflammatory phenotype and the downregulation of genes engaged in drug/xenobiotic metabolism. Only macrophages from CD showed, concomitant to an M1 phenotype, a significant enrichment in the expression of M2 and fibrotic and granuloma-related genes. For the first time, we showed (and validated by quantitative polymerase chain reaction and immunohistochemistry) that intestinal macrophages in patients with IBD present both M1 and M2 features, as recently described for tumor-associated macrophages, that affect key pathways for IBD pathology, represented by key markers such as MMP12 (fibrosis), CXCL9 (T-cell attraction), and CD40 (T-cell activation). CONCLUSIONS: Our data support the therapeutic targeting of macrophages to maintain remission in IBD but also indicate that a shift toward an M2 program-as proposed by some reports-may not limit the recruitment and activation of T cells because M2 features do not preclude M1 activation in patients with UC or CD and could exacerbate M2-related CD-specific features such as fibrosis and the formation of granulomas.


Assuntos
Colite Ulcerativa , Colite , Doença de Crohn , Doenças Inflamatórias Intestinais , Fibrose , Humanos , Mucosa Intestinal , Macrófagos
6.
Obes Surg ; 30(7): 2469-2474, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32318993

RESUMO

PURPOSE: Erosion of a laparoscopic adjustable gastric band (LAGB) is a devastating problem. There is no clear evidence in literature to guide the choice of revisional procedure following an eroded LAGB. The purpose of this study is to analyse the largest series of erosions following LAGB published to-date with an aim to share our experience with this rare complication and how we managed this cohort of patients following explantation of their LAGB. MATERIALS AND METHODS: This is a retrospective cohort study. Patient data is maintained prospectively in a surgical database. The study period was from January 1996 to January 2019. The outcomes of patients who underwent an erosion of LAGB were studied. RESULTS: Gastric band erosion was encountered in 4.7% of patients. Sixty patients opted for a revisional procedure which included 37 repeat LAGBs, 6 laparoscopic sleeve gastrectomies (LSG), 7 Roux-en-Y gastric bypasses (RYGB), 1 intragastric balloon, and 9 failed revisional procedures. Re-erosions were noted in 27% of patients who underwent a repeat gastric banding. Median %TWL at a 1-year follow-up was significantly higher in LSG and RYGB groups compared with that in LAGB (P < 0.008 and P < 0.000, respectively). There was no significant difference between the LSG and RYGB groups. CONCLUSION: The risk of re-erosion is increased in patients who undergo repeat AGB following a previous episode of erosion. Repeat LAGB should not be offered after a previous erosion. LSG and RYGB should be considered as appropriate revisional procedures in a patient who experience weight regain following explantation of an eroded LAGB.


Assuntos
Balão Gástrico , Derivação Gástrica , Gastroplastia , Laparoscopia , Obesidade Mórbida , Gastroplastia/efeitos adversos , Humanos , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso
7.
ACS Omega ; 5(1): 296-303, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31956776

RESUMO

The Collaborative Materials Exercise (CMX) is organized by the Nuclear Forensics International Technical Working Group, with the aim of advancing the analytical capabilities of the participating organizations and providing feedback on the best approaches to a nuclear forensic investigation. Here, model nuclear fuel materials from the 5th CMX iteration were analyzed using a NanoSIMS 50L (CAMECA) in order to examine inhomogeneities in the 235U/238U ratio and trace element abundance within individual, micrometer scale particles. Two fuel pellets were manufactured for the exercise and labelled CMX-5A and CMX-5B. These pellets were created using different processing techniques, but both had a target enrichment value of 235U/238U = 0.01. Particles from these pellets were isolated for isotopic and trace element analysis. Fifteen CMX-5A particles and 20 CMX-5B particles were analyzed, with both sample types displaying inhomogeneities in the U isotopic composition at a sub-micrometer scale within individual particles. Typical particle diameters were ∼1.5 to 41 µm for CMX-5A and ∼1 to 61 µm for CMX-5B. The CMX-5A particles were shown to be more isotopically homogeneous, with a mean 235U/238U atom ratio of 0.0130 ± 0.0066. The CMX-5B particles showed a predominantly depleted mean 235U/238U atom ratio of 0.0063 ± 0.0094, which is significantly different to the target enrichment value of the pellet and highlights the potential variation of 235U/238U in U fuel pellets at the micrometer scale. This study details the successful application of the NanoSIMS 50L in a mock nuclear forensic investigation by optimizing high-resolution imaging for uranium isotopics.

8.
J Crohns Colitis ; 14(3): 381-392, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-31626694

RESUMO

BACKGROUND AND AIMS: Mucosal healing is important in Crohn's disease therapies. Epithelial homeostasis becomes dysregulated in Crohn's, with increased permeability, inflammation, and diarrhoea. MicroRNAs are small non-coding RNAs that regulate gene expression and show changes in inflammatory bowel disease. Tumour necrosis factor alpha [TNFα] inhibitor protein 3 is raised in Crohn's and regulates TNFα-mediated activation of NFκB. We investigated TNFα regulation by microRNA in Crohn's disease [CD], and studied effects on epithelial permeability and inflammation. METHODS: Colonic epithelium from CD and healthy donor biopsies was isolated using laser capture microdissection, and microRNA was quantified. Tumour necrosis factor alpha inhibitor protein 3 was characterised immunohistochemically on serial sections. Expression effect of microRNA was confirmed with luciferase reporter assays. Functional barrier permeability studies and innate cytokine release were investigated with cell and explant culture studies. RESULTS: MicroRNA23a levels significantly increased in colonic Crohn's epithelium compared with healthy epithelium. Luciferase reporter assays in transfected epithelial cells confirmed that microRNA23a repressed expression via the 3' untranslated region of tumour necrosis factor alpha inhibitor protein 3 mRNA, coinciding with increased NFκB-mediated transcription. Immunohistochemical staining of TNFAIP3 protein in colonic biopsies was reduced or absent in adjacent Crohn's sections, correlating inversely with microRNA23a levels and encompassing some intercohort variation. Overexpression of microRNA23a increased epithelial barrier permeability in a colonic epithelial model and increased inflammatory cytokine release in cultured explant biopsies, mimicking Crohn's disease characteristics. CONCLUSIONS: MicroRNA23a overexpression in colonic Crohn's epithelium represses tumour necrosis factor alpha inhibitor protein 3, enhancing sensitivity to TNFα, with increased intestinal permeability and cytokine release.


Assuntos
Doença de Crohn , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , MicroRNAs/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Biópsia/métodos , Doença de Crohn/genética , Doença de Crohn/imunologia , Regulação da Expressão Gênica/imunologia , Humanos , Imuno-Histoquímica , Microdissecção e Captura a Laser/métodos , NF-kappa B/metabolismo , Permeabilidade , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
10.
Cell Death Differ ; 26(5): 943-957, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30050057

RESUMO

The contribution of epithelial-mesenchymal transition (EMT) to human lung fibrogenesis is controversial. Here we provide evidence that ZEB1-mediated EMT in human alveolar epithelial type II (ATII) cells contributes to the development of lung fibrosis by paracrine signalling to underlying fibroblasts. Activation of EGFR-RAS-ERK signalling in ATII cells induced EMT via ZEB1. ATII cells had extremely low extracellular matrix gene expression even after induction of EMT, however conditioned media from ATII cells undergoing RAS-induced EMT augmented TGFß-induced profibrogenic responses in lung fibroblasts. This epithelial-mesenchymal crosstalk was controlled by ZEB1 via the expression of tissue plasminogen activator (tPA). In human fibrotic lung tissue, nuclear ZEB1 expression was detected in alveolar epithelium adjacent to sites of extracellular matrix (ECM) deposition, suggesting that ZEB1-mediated paracrine signalling has the potential to contribute to early fibrotic changes in the lung interstitium. Targeting this novel ZEB1 regulatory axis may be a viable strategy for the treatment of pulmonary fibrosis.


Assuntos
Diferenciação Celular/genética , Fibrose/genética , Doenças Respiratórias/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Linhagem Celular , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Matriz Extracelular/genética , Fibrose/patologia , Regulação da Expressão Gênica/genética , Humanos , Pulmão/metabolismo , Pulmão/patologia , Miofibroblastos/metabolismo , Comunicação Parácrina/genética , Doenças Respiratórias/patologia
11.
Anesth Analg ; 127(2): 556-563, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30028389

RESUMO

BACKGROUND: Cortisol is a prototypical human stress hormone essential for life, yet the precise role of cortisol in the human stress response to injury or infection is still uncertain. Glucocorticoids (GCs) such as cortisol are widely understood to suppress inflammation and immunity. However, recent research shows that GCs also induce delayed immune effects manifesting as immune stimulation. In this study, we show that cortisol enhances the immune-stimulating effects of a prototypical proinflammatory cytokine, interferon-υ (IFN-υ). We tested the hypothesis that cortisol enhances IFN-υ-mediated proinflammatory responses of human mononuclear phagocytes (monocyte/macrophages [MOs]) stimulated by bacterial endotoxin (lipopolysaccharide [LPS]). METHODS: Human MOs were cultured for 18 hours with or without IFN-υ and/or cortisol before LPS stimulation. MO differentiation factors granulocyte-macrophage colony stimulating factor (GM-CSF) or M-CSF were added to separate cultures. We also compared the inflammatory response with an acute, 4-hour MO incubation with IFN-υ plus cortisol and LPS to a delayed 18-hour incubation with cortisol before LPS exposure. MO activation was assessed by interleukin-6 (IL-6) release and by multiplex analysis of pro- and anti-inflammatory soluble mediators. RESULTS: After the 18-hour incubation, we observed that cortisol significantly increased LPS-stimulated IL-6 release from IFN-υ-treated undifferentiated MOs. In GM-CSF-pretreated MOs, cortisol increased IFN-υ-mediated IL-6 release by >4-fold and release of the immune stimulant IFN-α2 (IFN-α2) by >3-fold, while suppressing release of the anti-inflammatory mediator, IL-1 receptor antagonist to 15% of control. These results were reversed by either the GC receptor antagonist RU486 or by an IFN-υ receptor type 1 antibody antagonist. Cortisol alone increased expression of the IFN-υ receptor type 1 on undifferentiated and GM-CSF-treated MOs. In contrast, an acute 4-hour incubation of MOs with IFN-υ and cortisol showed classic suppression of the IL-6 response to LPS. CONCLUSIONS: These results reveal a surprisingly robust proinflammatory interaction between the human stress response hormone cortisol and the immune activating cytokine IFN-υ. The results support an emerging physiological model with an adaptive role for cortisol, wherein acute release of cortisol suppresses early proinflammatory responses but also primes immune cells for an augmented response to a subsequent immune challenge. These findings have broad clinical implications and provide an experimental framework to examine individual differences, mechanisms, and translational implications of cortisol-enhanced immune responses in humans.


Assuntos
Glucocorticoides/farmacologia , Hidrocortisona/farmacologia , Sistema Imunitário/efeitos dos fármacos , Inflamação/tratamento farmacológico , Interferon gama/sangue , Adulto , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Voluntários Saudáveis , Humanos , Interleucina-6/metabolismo , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Reprodutibilidade dos Testes , Adulto Jovem
13.
Genes (Basel) ; 9(2)2018 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-29438285

RESUMO

Interleukin-13 (IL-13) is an important Type 2 T helper (Th2) cytokine, controlling biological functions in epithelium and has been linked to asthma, atopic dermatitis and ulcerative colitis (UC). Interleukin-13 signals through IL-13 receptor α-1 (IL13RA1 (gene) and IL13Rα1 (protein)), a receptor that can be regulated by microRNAs (miRs). MicroRNAs are small non-coding single-stranded RNAs with a role in several pathologies. However, their relevance in the pathophysiology of UC, a chronic inflammatory condition of the colonic mucosa, is poorly characterised. Here, we determined the expression of IL13Rα1 in UC, its potential regulation by miRs and the subsequent effect on IL-13 signalling. Inflamed mucosa of UC patients showed decreased mRNA and protein expression of IL13RA1 when compared to healthy controls. We show that miR-31 and miR-155 are upregulated in inflamed UC mucosa and that both directly target the 3' untranslated region of IL13RA1 mRNA. Transfection of miR-31 and miR-155 mimics reduced the expression of IL13RA1 mRNA and protein, and blocked IL-13-dependent phosphorylation of signal transducer and activator of transcription 6 (STAT6) in HT-29 cells, a gut epithelium cell line. Interleukin-13 activation of suppressor of cytokine signaling 1 (SOCS1) and eotaxin-3 (CCL26) expression was also diminished. MicroRNA-31/microRNA-155 mimics also downregulated IL13RA1 in ex vivo human inflamed UC biopsies. We propose that miR-31 and miR-155 have an important role in limiting IL-13 signalling in UC disease.

14.
Obes Surg ; 28(2): 520-525, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28836223

RESUMO

PURPOSE: The purpose of this study is to determine whether the reason for gastric band explantation would influence percentage excess weight loss (%EWL) following revisional Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). MATERIALS & METHODS: This is a retrospective cohort study, whose data are maintained in a prospective surgical database. The study period was from January 2012 to March 2017. Revisional surgeries were performed in a two-step manner, namely, first surgery LAGB explantation and second surgery (RYGB or SG). Two-way between-groups analysis of variance was used to examine effects of reason for band explantation (failed versus complication) and type of revisional surgery (RYGB versus SG) on %EWL at 10 months, 1 and 2 years. RESULTS: Cohort included 171 patients-146 women (85.4%) and 25 men, median age 51 years (range 22-76). Band-related complications accounted for 55% of explantations. Overall, 95 patients (56%) underwent a revisional RYGB, and 76 patients underwent a revisional SG. There was no difference in age or gender in terms of reason for band explantation or choice of revisional surgery. There was no difference in morbidity between the two groups (SG 2.6% versus RYGB 4.2%; p = .464). Patients undergoing revisional RYGB for failed weight loss had a significantly lower %EWL at 2 years compared to patients undergoing an SG for failed weight loss (p = .014) or an RYGB for band-related complications (p = .021). CONCLUSION: Patients undergoing revisional RYGB following band explantation for failed weight loss have a significantly lower %EWL at 2 years compared to patients undergoing an SG for failed weight loss or an RYGB for band-related complications.


Assuntos
Cirurgia Bariátrica/métodos , Remoção de Dispositivo/efeitos adversos , Gastroplastia/efeitos adversos , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/etiologia , Reoperação/métodos , Adulto , Idoso , Cirurgia Bariátrica/efeitos adversos , Bases de Dados Factuais , Remoção de Dispositivo/métodos , Falha de Equipamento , Feminino , Gastroplastia/instrumentação , Gastroplastia/métodos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Reoperação/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso , Adulto Jovem
15.
Immun Inflamm Dis ; 5(1): 45-56, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28250924

RESUMO

INTRODUCTION: The epithelial and endothelial barriers of the airway mucosa are critical for regulation of tissue homeostasis and protection against pathogens or other tissue damaging agents. In response to a viral infection, epithelial cells must signal to the endothelium to initiate immune cell recruitment. This is a highly temporal regulated process; however, the mechanisms of this cross-talk are not fully understood. METHODS: In a close-contact co-culture model of human airway epithelial and endothelial cells, cellular crosstalk was analyzed using transepithelial electrical resistance (TER) measurements, immunofluorescence, electron microscopy, and ELISA. Viral infections were simulated by exposing airway epithelial cells apically to double-stranded RNA (Poly(I:C)). Using a microfluidic culture system, the temporal release of mediators was analyzed in the co-culture model. RESULTS: Within 4 h of challenge, double-stranded RNA induced the release of TNF-α by epithelial cells. This activated endothelial cells by triggering the release of the chemoattractant CX3CL1 (fractalkine) by 8 h post-challenge and expression of adhesion molecules E-selectin and ICAM-1. These responses were significantly reduced by neutralising TNF-α. CONCLUSION: By facilitating kinetic profiling, the microfluidic co-culture system has enabled identification of a key signaling mechanism between the epithelial and endothelial barriers. Better understanding of cell-cell cross-talk and its regulatory mechanisms has the potential to identify new therapeutic strategies to control airway inflammation.


Assuntos
Comunicação Celular , Células Epiteliais/fisiologia , Células Endoteliais da Veia Umbilical Humana/fisiologia , Brônquios/citologia , Linhagem Celular , Células Cultivadas , Quimiocina CX3CL1/metabolismo , Técnicas de Cocultura , Selectina E/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Microfluídica , Poli I-C/farmacologia , RNA de Cadeia Dupla/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
16.
PLoS One ; 11(10): e0164438, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27792742

RESUMO

Pulmonary research requires models that represent the physiology of alveolar epithelium but concerns with reproducibility, consistency and the technical and ethical challenges of using primary or stem cells has resulted in widespread use of continuous cancer or other immortalized cell lines. The A549 'alveolar' cell line has been available for over four decades but there is an inconsistent view as to its suitability as an appropriate model for primary alveolar type II (ATII) cells. Since most work with A549 cells involves short term culture of proliferating cells, we postulated that culture conditions that reduced proliferation of the cancer cells would promote a more differentiated ATII cell phenotype. We examined A549 cell growth in different media over long term culture and then used microarray analysis to investigate temporal regulation of pathways involved in cell cycle and ATII differentiation; we also made comparisons with gene expression in freshly isolated human ATII cells. Analyses indicated that long term culture in Ham's F12 resulted in substantial modulation of cell cycle genes to result in a quiescent population of cells with significant up-regulation of autophagic, differentiation and lipidogenic pathways. There were also increased numbers of up- and down-regulated genes shared with primary cells suggesting adoption of ATII characteristics and multilamellar body (MLB) development. Subsequent Oil Red-O staining and Transmission Electron Microscopy confirmed MLB expression in the differentiated A549 cells. This work defines a set of conditions for promoting ATII differentiation characteristics in A549 cells that may be advantageous for studies with this cell line.


Assuntos
Células A549/fisiologia , Células Epiteliais Alveolares/fisiologia , Diferenciação Celular/fisiologia , Células A549/ultraestrutura , Células Epiteliais Alveolares/ultraestrutura , Técnicas de Cultura de Células , Ciclo Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Humanos , Microscopia Eletrônica de Transmissão , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Reação em Cadeia da Polimerase
17.
Brain Behav Immun ; 54: 86-94, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26790757

RESUMO

Glucocorticoids (GCs) are best known for their potent anti-inflammatory effects. However, an emerging model for glucocorticoid (GC) regulation of in vivo inflammation also includes a delayed, preparatory effect that manifests as enhanced inflammation following exposure to an inflammatory stimulus. When GCs are transiently elevated in vivo following exposure to a stressful event, this model proposes that a subsequent period of increased inflammatory responsiveness is adaptive because it enhances resistance to a subsequent stressor. In the present study, we examined the migratory response of human monocytes/macrophages following transient in vivo exposure to stress-associated concentrations of cortisol. Participants were administered cortisol for 6h to elevate in vivo cortisol levels to approximate those observed during major systemic stress. Monocytes in peripheral blood and macrophages in sterile inflammatory tissue (skin blisters) were studied before and after exposure to cortisol or placebo. We found that exposure to cortisol induced transient upregulation of monocyte mRNA for CCR2, the receptor for monocyte chemotactic protein-1 (MCP-1/CCL2) as well as for the chemokine receptor CX3CR1. At the same time, mRNA for the transcription factor IκBα was decreased. Monocyte surface expression of CCR2 but not CX3CR1 increased in the first 24h after cortisol exposure. Transient exposure to cortisol also led to an increased number of macrophages and neutrophils in fluid derived from a sterile inflammatory site in vivo. These findings suggest that the delayed, pro-inflammatory effects of cortisol on the human inflammatory responses may include enhanced localization of effector cells at sites of in vivo inflammation.


Assuntos
Movimento Celular/efeitos dos fármacos , Hidrocortisona/farmacologia , Monócitos/citologia , Monócitos/efeitos dos fármacos , Movimento Celular/imunologia , Quimiocina CCL2/farmacologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Feminino , Humanos , Hidrocortisona/sangue , Inflamação/metabolismo , Macrófagos/metabolismo , Macrófagos/fisiologia , Masculino , Monócitos/metabolismo , Neutrófilos/metabolismo , Neutrófilos/fisiologia , RNA Mensageiro/metabolismo , Receptores CCR2/biossíntese , Receptores CCR2/imunologia , Estresse Fisiológico , Regulação para Cima/efeitos dos fármacos
18.
PLoS One ; 10(10): e0139872, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26436734

RESUMO

The airway epithelium is exposed to a variety of harmful agents during breathing and appropriate cellular responses are essential to maintain tissue homeostasis. Recent evidence has highlighted the contribution of epithelial barrier dysfunction in the development of many chronic respiratory diseases. Despite intense research efforts, the responses of the airway barrier to environmental agents are not fully understood, mainly due to lack of suitable in vitro models that recapitulate the complex in vivo situation accurately. Using an interdisciplinary approach, we describe a novel dynamic 3D in vitro model of the airway epithelium, incorporating fully differentiated primary human airway epithelial cells at the air-liquid interface and a basolateral microfluidic supply of nutrients simulating the interstitial flow observed in vivo. Through combination of the microfluidic culture system with an automated fraction collector the kinetics of cellular responses by the airway epithelium to environmental agents can be analysed at the early phases for the first time and with much higher sensitivity compared to common static in vitro models. Following exposure of primary differentiated epithelial cells to pollen we show that CXCL8/IL-8 release is detectable within the first 2h and peaks at 4-6h under microfluidic conditions, a response which was not observed in conventional static culture conditions. Such a microfluidic culture model is likely to have utility for high resolution temporal profiling of toxicological and pharmacological responses of the airway epithelial barrier, as well as for studies of disease mechanisms.


Assuntos
Células Epiteliais/citologia , Microfluídica , Sistema Respiratório/citologia , Humanos , Técnicas In Vitro
19.
Health Psychol Res ; 2(2): 1464, 2014 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-26973932

RESUMO

Though advocated as useful for patients, there is little in the literature regarding the use and effectiveness of bariatric support groups. This study investigated characteristics and experiences of bariatric patients who did and did not attend offered groups. Seventy-eight postoperative laparoscopic adjustable gastric banding patients from a private bariatric clinic completed mailed self-report questionnaires. Almost 60% reported having attended the clinic groups, with most wanting to meet other patients and obtain information rather than access psychological assistance. Participants reported generally positive experiences of attending. Nonattendance was often attributed to practical barriers. Satisfaction with support from others was not related to past or predicted future attendance, but higher psychological distress was related to and predictive of greater intention to attend future groups. Likely future attenders also held more positive beliefs about the groups than those who were unlikely to attend. Further research is required into potential positive and negative consequences of attendance, and characteristics of those who are likely to benefit or be harmed by attending. Interventions addressing stereotypes about support groups may help patients make informed decisions about whether to attend a bariatric support group.

20.
Hepatology ; 59(4): 1492-504, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23873655

RESUMO

UNLABELLED: Active myofibroblast (MF) contraction contributes significantly to the increased intrahepatic vascular resistance that is the primary cause of portal hypertension (PHT) in cirrhosis. We sought proof of concept for direct therapeutic targeting of the dynamic component of PHT and markers of MF activation using short-term administration of the peptide hormone relaxin (RLN). We defined the portal hypotensive effect in rat models of sinusoidal PHT and the expression, activity, and function of the RLN-receptor signaling axis in human liver MFs. The effects of RLN were studied after 8 and 16 weeks carbon tetrachloride intoxication, following bile duct ligation, and in tissue culture models. Hemodynamic changes were analyzed by direct cannulation, perivascular flowprobe, indocyanine green imaging, and functional magnetic resonance imaging. Serum and hepatic nitric oxide (NO) levels were determined by immunoassay. Hepatic inflammation was assessed by histology and serum markers and fibrosis by collagen proportionate area. Gene expression was analyzed by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and western blotting and hepatic stellate cell (HSC)-MF contractility by gel contraction assay. Increased expression of RLN receptor (RXFP1) was shown in HSC-MFs and fibrotic liver diseases in both rats and humans. RLN induced a selective and significant reduction in portal pressure in pathologically distinct PHT models, through augmentation of intrahepatic NO signaling and a dramatic reduction in contractile filament expression in HSC-MFs. Critical for translation, RLN did not induce systemic hypotension even in advanced cirrhosis models. Portal blood flow and hepatic oxygenation were increased by RLN in early cirrhosis. Treatment of human HSC-MFs with RLN inhibited contractility and induced an antifibrogenic phenotype in an RXFP1-dependent manner. CONCLUSION: We identified RXFP1 as a potential new therapeutic target for PHT and MF activation status.


Assuntos
Hipertensão Portal/prevenção & controle , Cirrose Hepática/prevenção & controle , Fígado/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Relaxina/farmacologia , Relaxina/uso terapêutico , Actinas/metabolismo , Animais , Tetracloreto de Carbono/efeitos adversos , Células Cultivadas , Desmina/metabolismo , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Hipertensão Portal/induzido quimicamente , Hipertensão Portal/fisiopatologia , Fígado/metabolismo , Fígado/fisiopatologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/fisiopatologia , Masculino , Miofibroblastos/patologia , Miofibroblastos/fisiologia , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Relaxina/metabolismo
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