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1.
Nat Rev Mol Cell Biol ; 14(12): 759-74, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24201109

RESUMO

Healthy cells use autophagy as a general 'housekeeping' mechanism and to survive stress, including stress induced by nutrient deprivation. Autophagy is initiated at the isolation membrane (originally termed the phagophore), and the coordinated action of ATG (autophagy-related) proteins results in the expansion of this membrane to form the autophagosome. Although the biogenesis of the isolation membrane and the autophagosome is complex and incompletely understood, insight has been gained into the molecular processes involved in initiating the isolation membrane, the source from which this originates (for example, it was recently proposed that the isolation membrane forms from the mitochondria-associated endoplasmic reticulum (ER) membrane (MAM)) and the role of ATG proteins and the vesicular trafficking machinery in autophagosome formation.


Assuntos
Autofagia , Fagossomos/fisiologia , Animais , Endocitose , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/fisiologia , Humanos , Membranas Intracelulares/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Mitocôndrias/metabolismo , Complexos Multiproteicos/fisiologia , Transdução de Sinais , Serina-Treonina Quinases TOR/fisiologia , Proteínas de Transporte Vesicular/metabolismo
2.
BMC Cancer ; 24(1): 733, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877461

RESUMO

BACKGROUND: Checkpoint inhibitors (CPIs) are widely used in cancer treatment, with transformative impacts on survival. They nonetheless carry a significant risk of toxicity in the form of immune-related adverse events (IrAEs), which may be sustained and life-altering. IrAEs may require high-dose and/or prolonged steroid use and represent a significant healthcare burden. They mimic immune-mediated inflammatory diseases (IMIDs) but understanding of their pathogenesis is limited. The MEDALLION project aims to determine targetable mechanisms of immune dysregulation in IrAE development, employing an immune monitoring approach to determine changes in circulating and tissue resident cells of CPI recipients who do/do not develop them and assessing the contribution of the microbiome in parallel. METHODS: MEDALLION is a non-randomised longitudinal cohort study aiming to recruit 66 cancer patient recipients of anti-PD1/PD-L1, anti-CTLA-4 or combination therapy. Eligible participants include those with malignant melanoma in the adjuvant or metastatic setting, mesothelioma and non-small cell lung carcinoma (NSCLC) treated in the metastatic setting. Comprehensive clinical evaluation is carried out alongside blood, skin swab and stool sampling at the time of CPI initiation (baseline) and during subsequent routine hospital visits on 6 occasions over a 10-month follow-up period. It is conservatively anticipated that one third of enrolled patients will experience a "significant IrAE" (SirAE), defined according to pre-determined criteria specific to the affected tissue/organ system. Those developing such toxicity may optionally undergo a biopsy of affected tissue where appropriate, otherwise being managed according to standard of care. Peripheral blood mononuclear cells will be analysed using multi-parameter flow cytometry to investigate immune subsets, their activation status and cytokine profiles. Stool samples and skin swabs will undergo DNA extraction for 16 S ribosomal RNA (rRNA) sequencing and internal transcribed spacer (ITS) gene sequencing to determine bacterial and fungal microbiome diversity, respectively, including species associated with toxicity. Stored tissue biopsies will be available for in situ and single-cell transcriptomic evaluation. Analysis will focus on the identification of biological predictors and precursors of SirAEs. DISCUSSION: The pathogenesis of IrAEs will be assessed through the MEDALLION cohort, with the potential to develop tools for their prediction and/or strategies for targeted prevention or treatment. TRIAL REGISTRATION: The study was registered on 18/09/2023 in the ISRCTN registry (43,419,676).


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Estudos Longitudinais , Imunoterapia/métodos , Imunoterapia/efeitos adversos , Estudos de Coortes , Monitorização Imunológica/métodos , Melanoma/tratamento farmacológico , Melanoma/imunologia
3.
Gut ; 72(2): 295-305, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35902214

RESUMO

OBJECTIVE: Antitumour necrosis factor (TNF) drugs impair serological responses following SARS-CoV-2 vaccination. We sought to assess if a third dose of a messenger RNA (mRNA)-based vaccine substantially boosted anti-SARS-CoV-2 antibody responses and protective immunity in infliximab-treated patients with IBD. DESIGN: Third dose vaccine induced anti-SARS-CoV-2 spike (anti-S) receptor-binding domain (RBD) antibody responses, breakthrough SARS-CoV-2 infection, reinfection and persistent oropharyngeal carriage in patients with IBD treated with infliximab were compared with a reference cohort treated with vedolizumab from the impaCt of bioLogic therApy on saRs-cov-2 Infection and immuniTY (CLARITY) IBD study. RESULTS: Geometric mean (SD) anti-S RBD antibody concentrations increased in both groups following a third dose of an mRNA-based vaccine. However, concentrations were lower in patients treated with infliximab than vedolizumab, irrespective of whether their first two primary vaccine doses were ChAdOx1 nCoV-19 (1856 U/mL (5.2) vs 10 728 U/mL (3.1), p<0.0001) or BNT162b2 vaccines (2164 U/mL (4.1) vs 15 116 U/mL (3.4), p<0.0001). However, no differences in anti-S RBD antibody concentrations were seen following third and fourth doses of an mRNA-based vaccine, irrespective of the combination of primary vaccinations received. Post-third dose, anti-S RBD antibody half-life estimates were shorter in infliximab-treated than vedolizumab-treated patients (37.0 days (95% CI 35.6 to 38.6) vs 52.0 days (95% CI 49.0 to 55.4), p<0.0001).Compared with vedolizumab-treated, infliximab-treated patients were more likely to experience SARS-CoV-2 breakthrough infection (HR 2.23 (95% CI 1.46 to 3.38), p=0.00018) and reinfection (HR 2.10 (95% CI 1.31 to 3.35), p=0.0019), but this effect was uncoupled from third vaccine dose anti-S RBD antibody concentrations. Reinfection occurred predominantly during the Omicron wave and was predicted by SARS-CoV-2 antinucleocapsid concentrations after the initial infection. We did not observe persistent oropharyngeal carriage of SARS-CoV-2. Hospitalisations and deaths were uncommon in both groups. CONCLUSIONS: Following a third dose of an mRNA-based vaccine, infliximab was associated with attenuated serological responses and more SARS-CoV-2 breakthrough infection and reinfection which were not predicted by the magnitude of anti-S RBD responses, indicative of vaccine escape by the Omicron variant. TRIAL REGISTRATION NUMBER: ISRCTN45176516.


Assuntos
COVID-19 , Doenças Inflamatórias Intestinais , Vacinas , Humanos , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Infliximab/uso terapêutico , Pandemias , Reinfecção/epidemiologia , Reinfecção/prevenção & controle , Vacina BNT162 , ChAdOx1 nCoV-19 , Anticorpos Antivirais , Doenças Inflamatórias Intestinais/tratamento farmacológico
4.
Gastroenterology ; 162(5): 1525-1542, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34995532

RESUMO

Inflammatory bowel disease is characterized by significant interindividual heterogeneity. With a wider selection of pharmacologic and nonpharmacologic interventions available and in advanced developmental stages, a priority for the coming decade is to determine accurate methods of predicting treatment response and disease course. Precision medicine strategies will allow tailoring of preventative and therapeutic decisions to individual patient needs. In this review, we consider the future of precision medicine in inflammatory bowel disease. We discuss the critical need to extend from research focused on short-term symptomatic response to integrative multi-omic systems biology strategies to identify and validate biomarkers that underpin precision approaches. Crucially, the international community has collective responsibility to provide well-phenotyped and -curated longitudinal datasets for scientific discovery and validation. Research must also study broader aspects of the immune response, including components of the extracellular matrix, to better understand biological pathways initiating and perpetuating tissue fibrosis and longer-term disease complications.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Biomarcadores , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/terapia , Medicina de Precisão/métodos , Biologia de Sistemas/métodos
5.
J Immunol ; 207(9): 2245-2254, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34561227

RESUMO

Targeting interactions between α4ß7 integrin and endothelial adhesion molecule MAdCAM-1 to inhibit lymphocyte migration to the gastrointestinal tract is an effective therapy in inflammatory bowel disease (IBD). Following lymphocyte entry into the mucosa, a subset of these cells expresses αEß7 integrin, which is expressed on proinflammatory lymphocytes, to increase cell retention. The factors governing lymphocyte migration into the intestinal mucosa and αE integrin expression in healthy subjects and IBD patients remain incompletely understood. We evaluated changes in factors involved in lymphocyte migration and differentiation within tissues. Both ileal and colonic tissue from active IBD patients showed upregulation of ICAM-1, VCAM-1, and MAdCAM-1 at the gene and protein levels compared with healthy subjects and/or inactive IBD patients. ß1 and ß7 integrin expression on circulating lymphocytes was similar across groups. TGF-ß1 treatment induced expression of αE on both ß7+ and ß7- T cells, suggesting that cells entering the mucosa independently of MAdCAM-1/α4ß7 can become αEß7+ ITGAE gene polymorphisms did not alter protein induction following TGF-ß1 stimulation. Increased phospho-SMAD3, which is directly downstream of TGF-ß, and increased TGF-ß-responsive gene expression were observed in the colonic mucosa of IBD patients. Finally, in vitro stimulation experiments showed that baseline ß7 expression had little effect on cytokine, chemokine, transcription factor, and effector molecule gene expression in αE+ and αE- T cells. These findings suggest cell migration to the gut mucosa may be altered in IBD and α4ß7-, and α4ß7+ T cells may upregulate αEß7 in response to TGF-ß once within the gut mucosa.


Assuntos
Antígenos CD/metabolismo , Doenças Inflamatórias Intestinais/imunologia , Cadeias alfa de Integrinas/metabolismo , Cadeias beta de Integrinas/metabolismo , Mucosa Intestinal/imunologia , Receptores de Retorno de Linfócitos/metabolismo , Linfócitos T/imunologia , Adulto , Idoso , Movimento Celular , Feminino , Humanos , Cadeias beta de Integrinas/genética , Masculino , Pessoa de Meia-Idade , Transdução de Sinais , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
6.
Pediatr Res ; 92(4): 979-986, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34952939

RESUMO

BACKGROUND: IgA and its secretory form sIgA impact protection from infection and necrotising enterocolitis but little is known about quantities in preterm mums own milk (MOM) or infant stool, onset of endogenous production in the preterm gut, and what affects these. METHODS: We measured by ELISA in MOM and stool from healthy preterm infants total IgA and sIgA longitudinally and additionally in MOM fresh, refrigerated, frozen, and after traversing feeding systems. RESULTS: In 42 MOM (median gestation 26 weeks), we showed total IgA levels and sIgA were highest in colostrum, fell over 3 weeks, and were not impacted by gestation. Median IgA values matched previous term studies (700 mcg/ml). In MOM recipients stool IgA was detected in the first week, at around 30% of MOM quantities. Formula fed infants did not have detectable stool IgA until the third week. Levels of IgA and sIgA were approximately halved by handling processes. CONCLUSIONS: MOM in the 3 weeks after preterm delivery contains the highest concentrations of IgA and sIgA. Endogenous production after preterm birth occurs from the 3 week meaning preterm infants are dependent on MOM for IgA which should be optimised. Routine NICU practices halve the amount available to the infant. IMPACT: (Secretory) Immunoglobulin A (IgA) is present in colostrum of maternal milk from infants as preterm as 23-24 weeks gestational age, falling over the first 3 weeks to steady levels similar to term. Gestation at birth does not impact (secretory) IgA levels in breast milk. IgA is present in very preterm infant stools from maternal milk fed infants from the first week of life, but not in formula milk fed preterm infants until week three, suggesting endogenous production from this point. Refrigeration, freezing, and feeding via plastic tubing approximately halved the amount of IgA available.


Assuntos
Leite Humano , Nascimento Prematuro , Lactente , Feminino , Recém-Nascido , Humanos , Leite Humano/química , Recém-Nascido Prematuro , Imunoglobulina A Secretora , Valores de Referência , Plásticos , Aleitamento Materno
7.
Gut ; 70(12): 2273-2282, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33328245

RESUMO

OBJECTIVE: Necrotising enterocolitis (NEC) is a devastating intestinal disease primarily affecting preterm infants. The underlying mechanisms are poorly understood: mother's own breast milk (MOM) is protective, possibly relating to human milk oligosaccharide (HMO) and infant gut microbiome interplay. We investigated the interaction between HMO profiles and infant gut microbiome development and its association with NEC. DESIGN: We performed HMO profiling of MOM in a large cohort of infants with NEC (n=33) with matched controls (n=37). In a subset of 48 infants (14 with NEC), we also performed longitudinal metagenomic sequencing of infant stool (n=644). RESULTS: Concentration of a single HMO, disialyllacto-N-tetraose (DSLNT), was significantly lower in MOM received by infants with NEC compared with controls. A MOM threshold level of 241 nmol/mL had a sensitivity and specificity of 0.9 for NEC. Metagenomic sequencing before NEC onset showed significantly lower relative abundance of Bifidobacterium longum and higher relative abundance of Enterobacter cloacae in infants with NEC. Longitudinal development of the microbiome was also impacted by low MOM DSLNT associated with reduced transition into preterm gut community types dominated by Bifidobacterium spp and typically observed in older infants. Random forest analysis combining HMO and metagenome data before disease accurately classified 87.5% of infants as healthy or having NEC. CONCLUSION: These results demonstrate the importance of HMOs and gut microbiome in preterm infant health and disease. The findings offer potential targets for biomarker development, disease risk stratification and novel avenues for supplements that may prevent life-threatening disease.


Assuntos
Enterocolite Necrosante/microbiologia , Enterocolite Necrosante/prevenção & controle , Fezes/microbiologia , Leite Humano/química , Oligossacarídeos/metabolismo , Estudos de Casos e Controles , Feminino , Microbioma Gastrointestinal , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino
8.
Gut ; 70(10): 1884-1893, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33903149

RESUMO

OBJECTIVE: Delayed second dose SARS-CoV-2 vaccination trades maximal effectiveness for a lower level of immunity across more of the population. We investigated whether patients with inflammatory bowel disease treated with infliximab have attenuated serological responses to a single dose of a SARS-CoV-2 vaccine. DESIGN: Antibody responses and seroconversion rates in infliximab-treated patients (n=865) were compared with a cohort treated with vedolizumab (n=428), a gut-selective anti-integrin α4ß7 monoclonal antibody. Our primary outcome was anti-SARS-CoV-2 spike (S) antibody concentrations, measured using the Elecsys anti-SARS-CoV-2 spike (S) antibody assay 3-10 weeks after vaccination, in patients without evidence of prior infection. Secondary outcomes were seroconversion rates (defined by a cut-off of 15 U/mL), and antibody responses following past infection or a second dose of the BNT162b2 vaccine. RESULTS: Geometric mean (SD) anti-SARS-CoV-2 antibody concentrations were lower in patients treated with infliximab than vedolizumab, following BNT162b2 (6.0 U/mL (5.9) vs 28.8 U/mL (5.4) p<0.0001) and ChAdOx1 nCoV-19 (4.7 U/mL (4.9)) vs 13.8 U/mL (5.9) p<0.0001) vaccines. In our multivariable models, antibody concentrations were lower in infliximab-treated compared with vedolizumab-treated patients who received the BNT162b2 (fold change (FC) 0.29 (95% CI 0.21 to 0.40), p<0.0001) and ChAdOx1 nCoV-19 (FC 0.39 (95% CI 0.30 to 0.51), p<0.0001) vaccines. In both models, age ≥60 years, immunomodulator use, Crohn's disease and smoking were associated with lower, while non-white ethnicity was associated with higher, anti-SARS-CoV-2 antibody concentrations. Seroconversion rates after a single dose of either vaccine were higher in patients with prior SARS-CoV-2 infection and after two doses of BNT162b2 vaccine. CONCLUSION: Infliximab is associated with attenuated immunogenicity to a single dose of the BNT162b2 and ChAdOx1 nCoV-19 SARS-CoV-2 vaccines. Vaccination after SARS-CoV-2 infection, or a second dose of vaccine, led to seroconversion in most patients. Delayed second dosing should be avoided in patients treated with infliximab. TRIAL REGISTRATION NUMBER: ISRCTN45176516.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Fármacos Gastrointestinais/efeitos adversos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Infliximab/uso terapêutico , Adulto , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Vacina BNT162 , COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , ChAdOx1 nCoV-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Testes Sorológicos
9.
Gut ; 70(5): 865-875, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33753421

RESUMO

OBJECTIVE: Antitumour necrosis factor (anti-TNF) drugs impair protective immunity following pneumococcal, influenza and viral hepatitis vaccination and increase the risk of serious respiratory infections. We sought to determine whether infliximab-treated patients with IBD have attenuated serological responses to SARS-CoV-2 infections. DESIGN: Antibody responses in participants treated with infliximab were compared with a reference cohort treated with vedolizumab, a gut-selective anti-integrin α4ß7 monoclonal antibody that is not associated with impaired vaccine responses or increased susceptibility to systemic infections. 6935 patients were recruited from 92 UK hospitals between 22 September and 23 December 2020. RESULTS: Rates of symptomatic and proven SARS-CoV-2 infection were similar between groups. Seroprevalence was lower in infliximab-treated than vedolizumab-treated patients (3.4% (161/4685) vs 6.0% (134/2250), p<0.0001). Multivariable logistic regression analyses confirmed that infliximab (vs vedolizumab; OR 0.66 (95% CI 0.51 to 0.87), p=0.0027) and immunomodulator use (OR 0.70 (95% CI 0.53 to 0.92), p=0.012) were independently associated with lower seropositivity. In patients with confirmed SARS-CoV-2 infection, seroconversion was observed in fewer infliximab-treated than vedolizumab-treated patients (48% (39/81) vs 83% (30/36), p=0.00044) and the magnitude of anti-SARS-CoV-2 reactivity was lower (median 0.8 cut-off index (0.2-5.6) vs 37.0 (15.2-76.1), p<0.0001). CONCLUSIONS: Infliximab is associated with attenuated serological responses to SARS-CoV-2 that were further blunted by immunomodulators used as concomitant therapy. Impaired serological responses to SARS-CoV-2 infection might have important implications for global public health policy and individual anti-TNF-treated patients. Serological testing and virus surveillance should be considered to detect suboptimal vaccine responses, persistent infection and viral evolution to inform public health policy. TRIAL REGISTRATION NUMBER: ISRCTN45176516.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Fármacos Gastrointestinais/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Infliximab/uso terapêutico , SARS-CoV-2/imunologia , Adulto , Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testes Sorológicos , Reino Unido/epidemiologia
10.
Acta Paediatr ; 110(2): 450-457, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33245565

RESUMO

AIM: This narrative review summarises the benefits of maternal breastmilk to both the infant and the mother, specifically the benefits that relate to modification of the infant microbiome, and how this might vary in the preterm infant. METHODS: We used PubMed to primarily identify papers, reviews, case series and editorials published in English until May 2020. Based on this, we report on the components of breastmilk, their associated hypothesised benefits and the implications for clinical practice. RESULTS: Breastmilk is recommended as the exclusive diet for newborn infants because it has numerous nutritional and immunological benefits. Additionally, exposure to the maternal breastmilk microbiome may confer a lasting effect on gut health. In the preterm infant, breastmilk is associated with a significant reduction in necrotising enterocolitis, an inflammatory gastrointestinal disease and reduction in other key morbidities, together with improved neurodevelopmental outcomes. CONCLUSION: These impacts have long-term benefits for the child (and the mother) even after weaning. This benefit is likely due, in part, to modification of the infant gut microbiome by breastmilk microbes and bioactive components, and provide potential areas for research and novel therapies in preterm and other high-risk infants.


Assuntos
Enterocolite Necrosante , Microbioma Gastrointestinal , Criança , Enterocolite Necrosante/prevenção & controle , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Leite Humano , Mães
11.
Gut ; 69(10): 1769-1777, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32513653

RESUMO

OBJECTIVE: Management of acute severe UC (ASUC) during the novel COVID-19 pandemic presents significant dilemmas. We aimed to provide COVID-19-specific guidance using current British Society of Gastroenterology (BSG) guidelines as a reference point. DESIGN: We convened a RAND appropriateness panel comprising 14 gastroenterologists and an IBD nurse consultant supplemented by surgical and COVID-19 experts. Panellists rated the appropriateness of interventions for ASUC in the context of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Median scores and disagreement index (DI) were calculated. Results were discussed at a moderated meeting prior to a second survey. RESULTS: Panellists recommended that patients with ASUC should be isolated throughout their hospital stay and should have a SARS-CoV-2 swab performed on admission. Patients with a positive swab should be discussed with COVID-19 specialists. As per BSG guidance, intravenous hydrocortisone was considered appropriate as initial management; only in patients with COVID-19 pneumonia was its use deemed uncertain. In patients requiring rescue therapy, infliximab with continuing steroids was recommended. Delaying colectomy because of COVID-19 was deemed inappropriate. Steroid tapering as per BSG guidance was deemed appropriate for all patients apart from those with COVID-19 pneumonia in whom a 4-6 week taper was preferred. Post-ASUC maintenance therapy was dependent on SARS-CoV-2 status but, in general, biologics were more likely to be deemed appropriate than azathioprine or tofacitinib. Panellists deemed prophylactic anticoagulation postdischarge to be appropriate in patients with a positive SARS-CoV-2 swab. CONCLUSION: We have suggested COVID-19-specific adaptations to the BSG ASUC guideline using a RAND panel.


Assuntos
Betacoronavirus , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/terapia , Infecções por Coronavirus/epidemiologia , Controle de Infecções/organização & administração , Pneumonia Viral/epidemiologia , Doença Aguda , COVID-19 , Colite Ulcerativa/virologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Gastroenterologia , Humanos , Pandemias/prevenção & controle , Seleção de Pacientes , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Guias de Prática Clínica como Assunto , SARS-CoV-2 , Sociedades Médicas , Reino Unido
12.
Gut ; 69(6): 984-990, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32303607

RESUMO

The COVID-19 pandemic is putting unprecedented pressures on healthcare systems globally. Early insights have been made possible by rapid sharing of data from China and Italy. In the UK, we have rapidly mobilised inflammatory bowel disease (IBD) centres in order that preparations can be made to protect our patients and the clinical services they rely on. This is a novel coronavirus; much is unknown as to how it will affect people with IBD. We also lack information about the impact of different immunosuppressive medications. To address this uncertainty, the British Society of Gastroenterology (BSG) COVID-19 IBD Working Group has used the best available data and expert opinion to generate a risk grid that groups patients into highest, moderate and lowest risk categories. This grid allows patients to be instructed to follow the UK government's advice for shielding, stringent and standard advice regarding social distancing, respectively. Further considerations are given to service provision, medical and surgical therapy, endoscopy, imaging and clinical trials.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Doenças Inflamatórias Intestinais , Pandemias , Pneumonia Viral , Antivirais/efeitos adversos , Antivirais/uso terapêutico , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/terapia , Pneumonia Viral/complicações , Pneumonia Viral/terapia , Pneumonia Viral/transmissão , Medição de Risco , SARS-CoV-2 , Reino Unido , Tratamento Farmacológico da COVID-19
13.
EMBO J ; 35(3): 281-301, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26711178

RESUMO

Macroautophagy requires membrane trafficking and remodelling to form the autophagosome and deliver its contents to lysosomes for degradation. We have previously identified the TBC domain-containing protein, TBC1D14, as a negative regulator of autophagy that controls delivery of membranes from RAB11-positive recycling endosomes to forming autophagosomes. In this study, we identify the TRAPP complex, a multi-subunit tethering complex and GEF for RAB1, as an interactor of TBC1D14. TBC1D14 binds to the TRAPP complex via an N-terminal 103 amino acid region, and overexpression of this region inhibits both autophagy and secretory traffic. TRAPPC8, the mammalian orthologue of a yeast autophagy-specific TRAPP subunit, forms part of a mammalian TRAPPIII-like complex and both this complex and TBC1D14 are needed for RAB1 activation. TRAPPC8 modulates autophagy and secretory trafficking and is required for TBC1D14 to bind TRAPPIII. Importantly, TBC1D14 and TRAPPIII regulate ATG9 trafficking independently of ULK1. We propose a model whereby TBC1D14 and TRAPPIII regulate a constitutive trafficking step from peripheral recycling endosomes to the early Golgi, maintaining the cycling pool of ATG9 required for initiation of autophagy.


Assuntos
Autofagia , Proteínas Ativadoras de GTPase/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas Relacionadas à Autofagia , Linhagem Celular , Vesículas Citoplasmáticas/metabolismo , Humanos , Modelos Biológicos , Ligação Proteica , Mapeamento de Interação de Proteínas , Proteínas rab1 de Ligação ao GTP/metabolismo
15.
Muscle Nerve ; 62(3): 381-385, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32530515

RESUMO

INTRODUCTION: The sensitivity of repetitive nerve stimulation (RNS) in myasthenia gravis (MG) is dependent on the cutoff for abnormal decrement. METHODS: RNS data of adults with and without MG from 2014 to 2017 were reviewed retrospectively. The maximum reliable RNS amplitude/area decrement before and after exercise from facial, spinal accessory (SA), ulnar, and fibular nerves was recorded. Sensitivity/specificity using 5%, 7%, and 10% cutoffs were calculated. RESULTS: Seventy-nine of 141 patients had MG (46 generalized, 21 ocular, 12 bulbar). A total of 608 unique RNS recordings were analyzed. Overall RNS sensitivity/specificity at ≥5%, ≥7%, and ≥10% amplitude cutoffs were as follows: SA, 65.6%/86.3%, 49.2%/94.1%, and 29.5%/96.1%; facial, 51.0%/82.5%, 43.1%/95.0%, and 37.3%/100%; ulnar, 43.6%/100%, 41.0%/100%, and 41.0%/100%; and fibular, 52.6%/89.5%, 42.1%/94.7%, and 42.1%/100%. DISCUSSION: Lowering amplitude cutoff from 10% to 7% increased or maintained sensitivity with little loss in specificity. Post-exercise and area analysis resulted in increased sensitivity in some circumstances.


Assuntos
Nervo Acessório/fisiopatologia , Nervo Facial/fisiopatologia , Miastenia Gravis/diagnóstico , Nervo Fibular/fisiopatologia , Nervo Ulnar/fisiopatologia , Estimulação Elétrica , Eletrodiagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/fisiopatologia , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
EMBO Rep ; 19(4)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29437695

RESUMO

Trafficking of mammalian ATG9A between the Golgi apparatus, endosomes and peripheral ATG9A compartments is important for autophagosome biogenesis. Here, we show that the membrane remodelling protein SNX18, previously identified as a positive regulator of autophagy, regulates ATG9A trafficking from recycling endosomes. ATG9A is recruited to SNX18-induced tubules generated from recycling endosomes and accumulates in juxtanuclear recycling endosomes in cells lacking SNX18. Binding of SNX18 to Dynamin-2 is important for ATG9A trafficking from recycling endosomes and for formation of ATG16L1- and WIPI2-positive autophagosome precursor membranes. We propose a model where upon autophagy induction, SNX18 recruits Dynamin-2 to induce budding of ATG9A and ATG16L1 containing membranes from recycling endosomes that traffic to sites of autophagosome formation.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Dinamina II/metabolismo , Endossomos/metabolismo , Proteínas de Membrana/metabolismo , Nexinas de Classificação/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Autofagia , Proteínas de Transporte/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Membranas Intracelulares/metabolismo , Modelos Biológicos , Proteínas de Ligação a Fosfato , Ligação Proteica , Transporte Proteico
17.
Vet Radiol Ultrasound ; 61(1): 25-32, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31574584

RESUMO

In order to identify CT signs that could be used to distinguish cranial mediastinal lymphoma and thymic epithelial neoplasia, a retrospective case-control study was done. Associations between CT signs and diagnosis were tested using binary logistic regression and results expressed as odds ratio and 95% confidence interval. Sixty-two dogs that had thoracic CT and confirmed diagnosis of lymphoma (n = 33) or thymic neoplasia (n = 29) were sampled. Thymic neoplasms included 24 thymomas and five thymic carcinomas. Dogs with thymic epithelial neoplasia were significantly older than dogs with lymphoma (median age 8.6 years versus 6.0 years, P = .007), but there were no significant differences in prevalence of clinical signs. Diagnosis of thymic epithelial neoplasia was associated with heterogeneous attenuation in pre- (odds ratio 23.3, 95% confidence interval, 4.5-121.1) and post-contrast (odds ratio 30.7, 95% confidence interval, 3.6-265.0) images. Conversely, envelopment of the cranial vena cava by the mass was less likely with thymic epithelial neoplasia than lymphoma (odds ratio 0.07, 95% confidence interval, 0.007-0.66). Greater standard deviation of Hounsfield unit values in post-contrast images was associated with thymic epithelial neoplasia (P = .005). Based on ROC analysis, SD > 17HU of the mass in post-contrast images had a sensitivity of 72% and specificity of 79% for thymic epithelial neoplasia. There were no significant differences in morphology, prevalence of calcification, mediastinal lymphadenopathy, cranial vena cava invasion, collateral vessels, or pleural fluid associated with these tumors. Thymic epithelial neoplasms tended to occur in older dogs and were heterogeneous in CT images, whereas mediastinal lymphoma was more homogeneous and more likely to envelop the cranial vena cava.


Assuntos
Doenças do Cão/diagnóstico por imagem , Linfoma/veterinária , Neoplasias do Mediastino/veterinária , Neoplasias Epiteliais e Glandulares/veterinária , Neoplasias do Timo/veterinária , Tomografia Computadorizada por Raios X/veterinária , Veia Cava Superior/diagnóstico por imagem , Animais , Estudos de Casos e Controles , Cães , Feminino , Linfoma/diagnóstico por imagem , Masculino , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias Epiteliais e Glandulares/diagnóstico por imagem , Estudos Retrospectivos , Neoplasias do Timo/diagnóstico por imagem
19.
Gut ; 68(Suppl 3): s1-s106, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31562236

RESUMO

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.


Assuntos
Consenso , Tratamento Conservador/normas , Gerenciamento Clínico , Gastroenterologia , Doenças Inflamatórias Intestinais/terapia , Guias de Prática Clínica como Assunto/normas , Sociedades Médicas , Adulto , Humanos , Reino Unido
20.
BMC Microbiol ; 19(1): 52, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832576

RESUMO

BACKGROUND: Necrotising enterocolitis (NEC) is a common cause of death in preterm infants and is closely linked to the gut microbiota. Spontaneous intestinal perforation (SIP) also occurs in preterm neonates, but results in lower mortality and less adverse neonatal outcomes than NEC. Existing studies are largely limited to non-invasive stool samples, which may not be reflective of the anatomical site of disease. Therefore, we analysed historical formalin-fixed paraffin-embedded (FFPE) tissue from NEC and SIP preterm infants. A total of 13 NEC and 16 SIP infants were included. Extracted DNA from FFPE tissue blocks underwent 16S rRNA gene sequencing. For a subset of infants, diseased tissue and marginal healthy tissue from the same infant were compared. RESULTS: Xylene provided a cost and time effective means of deparaffinization. Tissue from the site of disease was highly comparable to adjacent healthier tissue. Comparing only diseased tissue from all infants showed significantly lower Shannon diversity in NEC (P = 0.026). The overall bacterial communities were also significantly different in NEC samples compared to SIP (P = 0.038), and large variability within NEC infants was observed. While no single OTU or genus was significantly associated with NEC or SIP, at the phylum level Proteobacteria (P = 0.045) and Bacteroidetes (P = 0.024) were significantly higher in NEC and SIP infants, respectively. CONCLUSIONS: Existing banks of intestinal FFPE blocks provide a robust and specific sample for profiling the microbiota at the site of disease. We showed preterm infants with NEC have lower diversity and different bacterial communities when compared to SIP controls.


Assuntos
Enterocolite Necrosante/microbiologia , Formaldeído , Microbioma Gastrointestinal , Perfuração Intestinal , Inclusão em Parafina , Bacteroidetes/classificação , DNA Bacteriano/isolamento & purificação , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Intestinos/microbiologia , Masculino , Proteobactérias/classificação , RNA Ribossômico 16S/genética , Ruptura Espontânea
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