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BACKGROUND & AIMS: Comparative assessments of immunogenicity following different COVID-19 vaccines in patients with distinct liver diseases are lacking. SARS-CoV-2-specific T-cell and antibody responses were evaluated longitudinally after one to three vaccine doses, with long-term follow-up for COVID-19-related clinical outcomes. METHODS: A total of 849 participants (355 with cirrhosis, 74 with autoimmune hepatitis [AIH], 36 with vascular liver disease [VLD], 257 liver transplant recipients [LTRs] and 127 healthy controls [HCs]) were recruited from four countries. Standardised immune assays were performed pre and post three vaccine doses (V1-3). RESULTS: In the total cohort, there were incremental increases in antibody titres after each vaccine dose (p <0.0001). Factors associated with reduced antibody responses were age and LT, whereas heterologous vaccination, prior COVID-19 and mRNA platforms were associated with greater responses. Although antibody titres decreased between post-V2 and pre-V3 (p = 0.012), patients with AIH, VLD, and cirrhosis had equivalent antibody responses to HCs post-V3. LTRs had lower and more heterogenous antibody titres than other groups, including post-V3 where 9% had no detectable antibodies; this was heavily influenced by intensity of immunosuppression. Vaccination increased T-cell IFNγ responses in all groups except LTRs. Patients with liver disease had lower functional antibody responses against nine Omicron subvariants and reduced T-cell responses to Omicron BA.1-specific peptides compared to wild-type. 122 cases of breakthrough COVID-19 were reported of which 5/122 (4%) were severe. Of the severe cases, 4/5 (80%) occurred in LTRs and 2/5 (40%) had no serological response post-V2. CONCLUSION: After three COVID-19 vaccines, patients with liver disease generally develop robust antibody and T-cell responses to vaccination and have mild COVID-19. However, LTRs have sustained no/low antibody titres and appear most vulnerable to severe disease. IMPACT AND IMPLICATIONS: Standardised assessments of the immune response to different COVID-19 vaccines in patients with liver disease are lacking. We performed antibody and T-cell assays at multiple timepoints following up to three vaccine doses in a large cohort of patients with a range of liver conditions. Overall, the three most widely available vaccine platforms were immunogenic and appeared to protect against severe breakthrough COVID-19. This will provide reassurance to patients with chronic liver disease who were deemed at high risk of severe COVID-19 during the pre-vaccination era, however, liver transplant recipients had the lowest antibody titres and remained vulnerable to severe breakthrough infection. We also characterise the immune response to multiple SARS-CoV-2 variants and describe the interaction between disease type, severity, and vaccine platform. These insights may prove useful in the event of future viral infections which also require rapid vaccine development and delivery to patients with liver disease.
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COVID-19 , Doenças do Sistema Digestório , Hepatite Autoimune , Hepatopatias , Transplante de Fígado , Humanos , Vacinas contra COVID-19 , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinação , Cirrose Hepática , Anticorpos , Imunidade , Anticorpos Antivirais , TransplantadosRESUMO
Allogeneic haematopoietic stem cell transplant (HSCT) recipients remain at high risk of adverse outcomes from coronavirus disease 2019 (COVID-19) and emerging variants. The optimal prophylactic vaccine strategy for this cohort is not defined. T cell-mediated immunity is a critical component of graft-versus-tumour effect and in determining vaccine immunogenicity. Using validated anti-spike (S) immunoglobulin G (IgG) and S-specific interferon-gamma enzyme-linked immunospot (IFNγ-ELIspot) assays we analysed response to a two-dose vaccination schedule (either BNT162b2 or ChAdOx1) in 33 HSCT recipients at ≤2 years from transplant, alongside vaccine-matched healthy controls (HCs). After two vaccines, infection-naïve HSCT recipients had a significantly lower rate of seroconversion compared to infection-naïve HCs (25/32 HSCT vs. 39/39 HCs no responders) and had lower S-specific T-cell responses. The HSCT recipients who received BNT162b2 had a higher rate of seroconversion compared to ChAdOx1 (89% vs. 74%) and significantly higher anti-S IgG titres (p = 0.022). S-specific T-cell responses were seen after one vaccine in HCs and HSCT recipients. However, two vaccines enhanced S-specific T-cell responses in HCs but not in the majority of HSCT recipients. These data demonstrate limited immunogenicity of two-dose vaccination strategies in HSCT recipients, bolstering evidence of the need for additional boosters and/or alternative prophylactic measures in this group.
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Vacinas contra COVID-19 , COVID-19 , Transplante de Células-Tronco Hematopoéticas , Fatores Etários , Anticorpos Antivirais/imunologia , Vacina BNT162/imunologia , Vacina BNT162/uso terapêutico , Transplante de Medula Óssea/efeitos adversos , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/farmacologia , Vacinas contra COVID-19/uso terapêutico , ChAdOx1 nCoV-19/imunologia , ChAdOx1 nCoV-19/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Imunidade Humoral/efeitos dos fármacos , Imunidade Humoral/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Soroconversão , Transplante Homólogo/efeitos adversos , Vacinação/efeitos adversosRESUMO
OPINION STATEMENT: Patients with hepatocellular carcinoma (HCC) have been traditionally deprived from highly effective systemic therapy options in the past decades. The multi-targeted tyrosine kinase inhibitor sorafenib, approved in 2008, remained the only treatment option for advanced HCC for over a decade. A number of molecularly targeted therapies such as lenvatinib, regorafenib, cabozantinib, and ramucirumab have significantly widened treatment options in patients with advanced HCC. However, emergence of resistance and long-term toxicity from treatment are barriers to long-term survivorship. Immunotherapy is at the focus of intense research efforts in HCC. Whilst targeting of programmed cell death 1 (PD-1) and cytotoxic T lymphocyte 4 (CTLA-4) is associated with radiologically measurable disease-modulating effects in HCC, monotherapies fell short of demonstrating evidence of significant survival extension in advanced disease. Atezolizumab and bevacizumab were the first immunotherapy regimen to demonstrate clear superiority in improving the survival of patients with unresectable HCC compared to sorafenib, paving the way for immunotherapy combinations. As the treatment landscape of HCC rapidly evolves, with immunotherapy integrating within early- and intermediate-stage disease treatment algorithms, lack of level 1 evidence on sequencing of therapeutic strategies and lack of head-to-head comparisons across immunotherapy combinations will affect prescribing of immunotherapy in routine practice. In the absence of predictive biomarkers, choice of immunotherapy over kinase inhibitors will continue to remain an empirical exercise, guided by balancing anti-tumour efficacy with toxicity considerations in the individual patient.
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Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno CTLA-4/antagonistas & inibidores , Humanos , Terapia Neoadjuvante , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidoresRESUMO
BACKGROUND: Rectal non-steroidal anti-inflammatory drug at endoscopic retrograde cholangiopancreatography is now the standard of care to reduce the risk of post-ERCP pancreatitis. Pancreatic duct stenting also reduces the risk of post- ERCP pancreatitis in high-risk patients, but failed pancreatic duct stenting carries an increased PEP rate (up to 35%). STUDY AIM: To assess the impact on post-ERCP pancreatitis of successful and unsuccessful pancreatic duct stent placement in the setting of universal rectal non-steroidal anti-inflammatory drug use. METHODS: Between 2013-2015, all patients undergoing endoscopic retrograde cholangiopancreatographys in our tertiary referral centre (where rectal non-steroidal anti-inflammatory drugs are used routinely) were included. The electronic patient's records were reviewed and the following parameters were analysed: indication for pancreatic duct stenting; deployment success; and adverse events. RESULTS: A total of 1633 endoscopic retrograde cholangiopancreatographys were performed, and pancreatic duct stenting was attempted in 324 cases (20%), with successful placement in 307 patients (95%). Contra-indications to non-steroidal anti-inflammatory drugs were found in 106 (6.5%) patients. Prophylactic stenting failed in 12 of 213 patients; of whom one patient developed post-ERCP pancreatitis (8%). Eighteen (9%) patients with prophylactic pancreatic duct stents developed post-ERCP pancreatitis compared to 1.4% without prophylactic stents (RR 8.4, p=0.04). CONCLUSION: A lack of difference in post-ERCP pancreatitis in those who underwent successful, and unsuccessful, pancreatic duct stent placement may reflect the protective effect of non-steroidal anti-inflammatory drugs. This data adds to evidence suggesting that pancreatic duct stenting may be less important, even in high-risk patients, with the widespread use of non-steroidal anti-inflammatory drugs.
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Ciguatoxins (CTXs), and possibly maitotoxins (MTXs), are responsible for Ciguatera Fish Poisoning, an important health problem for consumers of reef fish (such as inhabitants of islands in the South Pacific Ocean). The habitational range of the Gambierdiscus species is expanding, and new species are being discovered. In order to provide information on the potential health risk of the Gambierdiscus species, and one Fukuyoa species (found in the Cook Islands, the Kermadec Islands, mainland New Zealand, and New South Wales, Australia), 17 microalgae isolates were collected from these areas. Unialgal cultures were grown and extracts of the culture isolates were analysed for CTXs and MTXs by liquid chromatography tandem mass spectrometry (LC-MS/MS), and their toxicity to mice was determined by intraperitoneal and oral administration. An isolate of G. carpenteri contained neither CTXs nor MTXs, while 15 other isolates (including G. australes, G. cheloniae, G. pacificus, G.honu, and F. paulensis) contained only MTX-1 and/or MTX-3. An isolate of G. polynesiensis contained both CTXs and MTX-3. All the extracts were toxic to mice by intraperitoneal injection, but those containing only MTX-1 and/or -3 were much less toxic by oral administration. The extract of G. polynesiensis was highly toxic by both routes of administration.
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Ciguatoxinas/toxicidade , Dinoflagellida/química , Toxinas Marinhas/toxicidade , Oxocinas/toxicidade , Administração Oral , Animais , Cromatografia Líquida , Ciguatera/epidemiologia , Ciguatoxinas/administração & dosagem , Ciguatoxinas/isolamento & purificação , Feminino , Injeções Intraperitoneais , Toxinas Marinhas/administração & dosagem , Toxinas Marinhas/isolamento & purificação , Camundongos , Oxocinas/administração & dosagem , Oxocinas/isolamento & purificação , Oceano Pacífico , Especificidade da Espécie , Espectrometria de Massas em Tandem , Testes de ToxicidadeRESUMO
Species in the genus Gambierdiscus produce ciguatoxins (CTXs) and/or maitotoxins (MTXs), which may cause ciguatera fish poisoning (CFP) in humans if contaminated fish are consumed. Species of Gambierdiscus have previously been isolated from macroalgae at Rangitahua (Raoul Island and North Meyer Islands, northern Kermadec Islands), and the opportunity was taken to sample for Gambierdiscus at the more southerly Macauley Island during an expedition in 2016. Gambierdiscus cells were isolated, cultured, and DNA extracted and sequenced to determine the species present. Bulk cultures were tested for CTXs and MTXs by liquid chromatography-mass spectrometry (LC-MS/MS). The species isolated were G. australes, which produced MTX-1 (ranging from 3 to 36 pg/cell), and G. polynesiensis, which produced neither MTX-1 nor, unusually, any known CTXs. Isolates of both species produced putative MTX-3. The risk of fish, particularly herbivorous fish, causing CFP in the Zealandia and Kermadec Islands region is real, although in mainland New Zealand the risk is currently low. Both Gambierdiscus and Fukuyoa have been recorded in the sub-tropical northern region of New Zealand, and so the risk may increase with warming seas and shift in the distribution of Gambierdiscus species.
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Ciguatera/etiologia , Ciguatoxinas/toxicidade , Dinoflagellida/genética , Dinoflagellida/isolamento & purificação , Peixes/parasitologia , Animais , Ilhas , Nova Zelândia , Espectrometria de Massas em TandemRESUMO
INTRODUCTION: Endoscopic transmural drainage (ED) or percutaneous drainage (PD) has mostly replaced surgery for the initial management of patients with symptomatic pancreatic fluid collections (PFCs). This study aimed to compare outcomes for patients undergoing ED or PD of symptomatic PFCs. METHODS: Between January 2000 and December 2013, all patients who required PD or ED of a PFC were included. Rates of treatment success, length of hospital stay, adverse events, re-interventions and length of follow-up were recorded retrospectively in all cases. RESULTS: In total, 164 patients were included in the study; 109 patients underwent ED; and 55 had PD alone. During the 14-year study period, the incidence of ED increased and PD fell. In the 109 patients who were managed by ED, treatment success was considerably higher than in those managed by PD (70 vs. 31 %). Rates of procedural adverse events were higher in the ED cohort compared to the PD group (10 vs. 1 %), but patients managed by ED required fewer interventions (median of 1.8 vs. 3.3) had lower rates of residual collections (21 vs. 67 %) and need for surgical intervention (4 vs. 11 %). In the ED group, treatment success was similar for walled-off pancreatic necrosis (WOPN) and pseudocysts (67 vs. 72 %, P = 0.77). There were no procedure-related deaths. CONCLUSION: Compared with PD, ED of symptomatic PFCs was associated with higher rates of treatment success, lower rates of re-intervention, including surgery and shorter lengths of hospital stay. Outcomes in WOPN were comparable to those in patients with pseudocysts.
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Drenagem , Pancreatopatias/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Endoscopia/métodos , Feminino , Humanos , Laparoscopia/métodos , Tempo de Internação , Londres , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: The humoral and T-cell responses to booster COVID-19 vaccine types in multidisease immunocompromised individuals who do not generate adequate antibody responses to two COVID-19 vaccine doses, is not fully understood. The OCTAVE DUO trial aimed to determine the value of third vaccinations in a wide range of patients with primary and secondary immunodeficiencies. METHODS: OCTAVE-DUO was a prospective, open-label, multicentre, randomised, controlled, phase 3 trial investigating humoral and T-cell responses in patients who are immunocompromised following a third vaccine dose with BNT162b2 or mRNA-1273, and of NVX-CoV2373 for those with lymphoid malignancies. We recruited patients who were immunocompromised from 11 UK hospitals, aged at least 18 years, with previous sub-optimal responses to two doses of SARS-CoV-2 vaccine. Participants were randomly assigned 1:1 (1:1:1 for those with lymphoid malignancies), stratified by disease, previous vaccination type, and anti-spike antibody response following two doses. Individuals with lived experience of immune susceptibility were involved in the study design and implementation. The primary outcome was vaccine-specific immunity defined by anti-SARS-CoV-2 spike antibodies (Roche Diagnostics UK and Ireland, Burgess Hill, UK) and T-cell responses (Oxford Immunotec, Abingdon, UK) before and 21 days after the third vaccine dose analysed by a modified intention-to-treat analysis. The trial is registered with the ISRCTN registry, ISRCTN 15354495, and the EU Clinical Trials Register, EudraCT 2021-003632-87, and is complete. FINDINGS: Between Aug 4, 2021 and Mar 31, 2022, 804 participants across nine disease cohorts were randomly assigned to receive BNT162b2 (n=377), mRNA-1273 (n=374), or NVX-CoV2373 (n=53). 356 (45%) of 789 participants were women, 433 (55%) were men, and 659 (85%) of 775 were White. Anti-SARS-CoV-2 spike antibodies measured 21 days after the third vaccine dose were significantly higher than baseline pre-third dose titres in the modified intention-to-treat analysis (median 1384 arbitrary units [AU]/mL [IQR 4·3-7990·0] compared with median 11·5 AU/mL [0·4-63·1]; p<0·001). Of participants who were baseline low responders, 380 (90%) of 423 increased their antibody concentrations to more than 400 AU/mL. Conversely, 166 (54%) of 308 baseline non-responders had no response after the third dose. Detectable T-cell responses following the third vaccine dose were seen in 494 (80%) of 616 participants. There were 24 serious adverse events (BNT612b2 eight [33%] of 24, mRNA-1273 12 [50%], NVX-CoV2373 four [17%]), two (8%) of which were categorised as vaccine-related. There were seven deaths (1%) during the trial, none of which were vaccine-related. INTERPRETATION: A third vaccine dose improved the serological and T-cell response in the majority of patients who are immunocompromised. Individuals with chronic renal disease, lymphoid malignancy, on B-cell targeted therapies, or with no serological response after two vaccine doses are at higher risk of poor response to a third vaccine dose. FUNDING: Medical Research Council, Blood Cancer UK.
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Vacina BNT162 , Vacinas contra COVID-19 , COVID-19 , Hospedeiro Imunocomprometido , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , Feminino , Masculino , COVID-19/prevenção & controle , COVID-19/imunologia , Pessoa de Meia-Idade , Hospedeiro Imunocomprometido/imunologia , SARS-CoV-2/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Idoso , Vacina BNT162/imunologia , Vacina BNT162/administração & dosagem , Anticorpos Antivirais/sangue , Estudos Prospectivos , Imunização Secundária , Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Adulto , Linfócitos T/imunologia , Reino Unido , ChAdOx1 nCoV-19/imunologiaRESUMO
Pre-existing cross-reactive immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proteins in infection-naive subjects have been described by several studies. In particular, regions of high homology between SARS-CoV-2 and common cold coronaviruses have been highlighted as a likely source of this cross-reactivity. However, the role of such cross-reactive responses in the outcome of SARS-CoV-2 infection and vaccination is currently unclear. Here, we review evidence regarding the impact of pre-existing humoral and T cell immune responses to outcomes of SARS-CoV-2 infection and vaccination. Furthermore, we discuss the importance of conserved coronavirus epitopes for the rational design of pan-coronavirus vaccines and consider cross-reactivity of immune responses to ancestral SARS-CoV-2 and SARS-CoV-2 variants, as well as their impact on COVID-19 vaccination.
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COVID-19 , Vacinas , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinas contra COVID-19 , VacinaçãoRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immune responses and infection outcomes were evaluated in 2,686 patients with varying immune-suppressive disease states after administration of two Coronavirus Disease 2019 (COVID-19) vaccines. Overall, 255 of 2,204 (12%) patients failed to develop anti-spike antibodies, with an additional 600 of 2,204 (27%) patients generating low levels (<380 AU ml-1). Vaccine failure rates were highest in ANCA-associated vasculitis on rituximab (21/29, 72%), hemodialysis on immunosuppressive therapy (6/30, 20%) and solid organ transplant recipients (20/81, 25% and 141/458, 31%). SARS-CoV-2-specific T cell responses were detected in 513 of 580 (88%) patients, with lower T cell magnitude or proportion in hemodialysis, allogeneic hematopoietic stem cell transplantation and liver transplant recipients (versus healthy controls). Humoral responses against Omicron (BA.1) were reduced, although cross-reactive T cell responses were sustained in all participants for whom these data were available. BNT162b2 was associated with higher antibody but lower cellular responses compared to ChAdOx1 nCoV-19 vaccination. We report 474 SARS-CoV-2 infection episodes, including 48 individuals with hospitalization or death from COVID-19. Decreased magnitude of both the serological and the T cell response was associated with severe COVID-19. Overall, we identified clinical phenotypes that may benefit from targeted COVID-19 therapeutic strategies.
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COVID-19 , SARS-CoV-2 , Humanos , Vacinas contra COVID-19 , Vacina BNT162 , ChAdOx1 nCoV-19 , Vacinação , Anticorpos AntiviraisRESUMO
BACKGROUND: Both infection and vaccination, alone or in combination, generate antibody and T cell responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the maintenance of such responses-and hence protection from disease-requires careful characterization. In a large prospective study of UK healthcare workers (HCWs) (Protective Immunity from T Cells in Healthcare Workers [PITCH], within the larger SARS-CoV-2 Immunity and Reinfection Evaluation [SIREN] study), we previously observed that prior infection strongly affected subsequent cellular and humoral immunity induced after long and short dosing intervals of BNT162b2 (Pfizer/BioNTech) vaccination. METHODS: Here, we report longer follow-up of 684 HCWs in this cohort over 6-9 months following two doses of BNT162b2 or AZD1222 (Oxford/AstraZeneca) vaccination and up to 6 months following a subsequent mRNA booster vaccination. FINDINGS: We make three observations: first, the dynamics of humoral and cellular responses differ; binding and neutralizing antibodies declined, whereas T and memory B cell responses were maintained after the second vaccine dose. Second, vaccine boosting restored immunoglobulin (Ig) G levels; broadened neutralizing activity against variants of concern, including Omicron BA.1, BA.2, and BA.5; and boosted T cell responses above the 6-month level after dose 2. Third, prior infection maintained its impact driving larger and broader T cell responses compared with never-infected people, a feature maintained until 6 months after the third dose. CONCLUSIONS: Broadly cross-reactive T cell responses are well maintained over time-especially in those with combined vaccine and infection-induced immunity ("hybrid" immunity)-and may contribute to continued protection against severe disease. FUNDING: Department for Health and Social Care, Medical Research Council.
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COVID-19 , Vacinas , Humanos , Vacinas contra COVID-19 , Vacina BNT162 , ChAdOx1 nCoV-19 , Estudos Prospectivos , SARS-CoV-2 , Anticorpos Neutralizantes , Pessoal de Saúde , Imunidade HumoralRESUMO
Background and study aims Virtual reality endoscopic simulation training has the potential to expedite competency development in novice trainees. However, simulation platforms must be realistic and confer face validity. This study aimed to determine the face validity of high-fidelity virtual reality simulation (EndoSim, Surgical Science, Gothenburg), and establish benchmark metrics to guide the development of a Simulation Pathway to Improve Competency in Endoscopy (SPICE). Methods A pilot cohort of four experts rated simulated exercises (Likert scale score 1-5) and following iterative development, 10 experts completed 13 simulator-based endoscopy exercises amounting to 859 total metric values. Results Expert metric performance demonstrated equivalence ( P â=â0.992). In contrast, face validity of each exercise varied among experts (median 4 (interquartile range [IQR] 3-5), P â<â0.003) with Mucosal Examination receiving the highest scores (median 5 [IQR 4.5-5], P â=â1.000) and Loop Management and Intubation exercises receiving the lowest scores (median 3 [IQR 1-3], P â<â0.001, P â=â0.004), respectively. The provisional validated SPICE comprised 13 exercises with pass marks and allowance buffers defined by median and IQR expert performance. Conclusions EndoSim Face Validity was very good related to early scope handling skills, but more advanced competencies and translation of acquired clinical skills require further research within an established training program. The existing training deficit with superadded adverse effects of the COVID pandemic make this initiative an urgent priority.
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Chlamydia trachomatis is the causative agent of a highly prevalent sexually transmitted bacterial disease and is associated with a number of severe disease complications. Current therapy options are successful at treating disease, but patients are left without protective immunity and do not benefit the majority asymptomatic patients who do not seek treatment. As such, there is a clear need for a broad acting, protective vaccine that can prevent transmission and protect against symptomatic disease presentation. There are three key elements that underlie successful vaccine development: 1) Chlamydia biology and immune-evasion adaptations, 2) the correlates of protection that prevent disease in natural and experimental infection, 3) reflection upon the evidence provided by previous vaccine attempts. In this review, we give an overview of the unique intra-cellular biology of C. trachomatis and give insight into the dynamic combination of adaptations that allow Chlamydia to subvert host immunity and survive within the cell. We explore the current understanding of chlamydial immunity in animal models and in humans and characterise the key immune correlates of protection against infection. We discuss in detail the specific immune interactions involved in protection, with relevance placed on the CD4+ T lymphocyte and B lymphocyte responses that are key to pathogen clearance. Finally, we provide a timeline of C. trachomatis vaccine research to date and evaluate the successes and failures in development so far. With insight from these three key elements of research, we suggest potential solutions for chlamydial vaccine development and promising avenues for further exploration.
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Infecções por Chlamydia , Chlamydia trachomatis , Animais , Vacinas Bacterianas , Linfócitos T CD4-Positivos , Infecções por Chlamydia/prevenção & controle , Humanos , VacinaçãoRESUMO
As SARS-CoV-2 vaccines are deployed worldwide, a comparative evaluation is important to underpin decision-making. We here report a systematic literature review and meta-analysis of Phase I/II/III human trials and non-human primates (NHP) studies, comparing reactogenicity, immunogenicity and efficacy across different vaccine platforms for comparative evaluation (updated to March 22, 2021). Twenty-three NHP and 32 human studies are included. Vaccines result in mostly mild, self-limiting adverse events. Highest spike neutralizing antibody (nAb) responses are identified for the mRNA-1273-SARS-CoV and adjuvanted NVX-CoV2373-SARS-CoV-2 vaccines. ChAdOx-SARS-CoV-2 produces the highest T cell ELISpot responses. Pre-existing nAb against vaccine viral vector are identified following AdH-5-SARS-CoV-2 vaccination, halving immunogenicity. The mRNA vaccines depend on boosting to achieve optimal immunogenicity especially in the elderly. BNT162b2, and mRNA-1273 achieve >94%, rAd26/5 > 91% and ChAdOx-SARS-CoV-2 > 66.7% efficacy. Across different vaccine platforms there are trade-offs between antibody binding, functional nAb titers, T cell frequency, reactogenicity and efficacy. Emergence of variants makes rapid mass rollout of high efficacy vaccines essential to reduce any selective advantage.
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Medical shortages during the COVID-19 pandemic saw numerous efforts to 3D print personal protective equipment and treatment supplies. There is, however, little research on the potential biocompatibility of 3D-printed parts using typical polymeric resins as pertaining to volatile organic compounds (VOCs), which have specific relevance for respiratory circuit equipment. Here, we measured VOCs emitted from freshly printed stereolithography (SLA) replacement medical parts using proton transfer reaction mass spectrometry and infrared differential absorption spectroscopy, and particulates using a scanning mobility particle sizer. We observed emission factors for individual VOCs ranging from â¼0.001 to â¼10 ng cm-3 min-1. Emissions were heavily dependent on postprint curing and mildly dependent on the type of SLA resin. Curing reduced the emission of all observed chemicals, and no compounds exceeded the recommended dose of 360 µg/d. VOC emissions steadily decreased for all parts over time, with an average e-folding time scale (time to decrease to 1/e of the starting value) of 2.6 ± 0.9 h.
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BACKGROUND: Modulation of adaptive immunity may underscore the efficacy of trans-arterial chemoembolization (TACE). We evaluated the influence of TACE on T-cell function by phenotypic lymphocyte characterization in samples of patients undergoing surgery with (T+) or without (T-) prior-TACE treatment. METHODS: We profiled intratumoral (IT), peritumoral (PT) and non-tumoral (NT) background tissue to evaluate regulatory CD4+/FOXP3+ (T-reg) and immune-exhausted CD8+/PD-1+ T-cells across T+ (n=58) and T- (n=61). We performed targeted transcriptomics and T-cell receptor sequencing in a restricted subset of samples (n=24) evaluated in relationship with the expression of actionable drivers of anti-cancer immunity including PD-L1, indoleamine 2,3 dehydrogenase (IDO-1), cytotoxic T-lymphocyte associated protein 4 (CTLA-4), Lag-3, Tim-3 and CD163. RESULTS: We analyzed 119 patients resected (n=25, 21%) or transplanted (n=94, 79%) for Child-Pugh A (n=65, 55%) and Barcelona Clinic Liver Cancer stage A (n=92, 77%) hepatocellular carcinoma. T+ samples displayed lower IT CD4+/FOXP3+ (p=0.006), CD8+ (p=0.002) and CD8+/PD-1+ and NT CD8+/PD-1+ (p<0.001) compared with T-. Lower IT (p=0.005) and NT CD4+/FOXP3+ (p=0.03) predicted for improved recurrence-free survival. In a subset of samples (n=24), transcriptomic analysis revealed upregulation of a pro-inflammatory response in T+. T+ samples were enriched for IRF2 expression (p=0.01), an interferon-regulated transcription factor implicated in cancer immune-evasion. T-cell clonality and expression of PD-L1, IDO-1, CTLA-4, Lag-3, Tim-3 and CD163 was similar in T+ versus T-. CONCLUSIONS: TACE is associated with lower IT density of immune-exhausted effector cytotoxic and T-regs, with significant upregulation of pro-inflammatory pathways. This highlights the pleiotropic effects of TACE in modulating the tumor microenvironment and strengthens the rationale for developing immunotherapy alongside TACE.
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Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica/métodos , Morte Celular Imunogênica/efeitos dos fármacos , Imunoterapia/métodos , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
Understanding the nature of immunity following mild/asymptomatic infection with SARS-CoV-2 is crucial to controlling the pandemic. We analyzed T cell and neutralizing antibody responses in 136 healthcare workers (HCW) 16-18 weeks after United Kingdom lockdown, 76 of whom had mild/asymptomatic SARS-CoV-2 infection captured by serial sampling. Neutralizing antibodies (nAb) were present in 89% of previously infected HCW. T cell responses tended to be lower following asymptomatic infection than in those reporting case-definition symptoms of COVID-19, while nAb titers were maintained irrespective of symptoms. T cell and antibody responses were sometimes discordant. Eleven percent lacked nAb and had undetectable T cell responses to spike protein but had T cells reactive with other SARS-CoV-2 antigens. Our findings suggest that the majority of individuals with mild or asymptomatic SARS-CoV-2 infection carry nAb complemented by multispecific T cell responses at 16-18 weeks after mild or asymptomatic SARS-CoV-2 infection.
Assuntos
Anticorpos Neutralizantes/imunologia , Infecções Assintomáticas , COVID-19/imunologia , Linfócitos T/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Estudos de Casos e Controles , Estudos Transversais , Humanos , SARS-CoV-2/imunologiaRESUMO
Patient safety incidents occur throughout healthcare and early reports have exposed how deficiencies in 'human factors' have contributed to mortality in endoscopy. Recognising this, in the UK, the Joint Advisory Group for Gastrointestinal Endoscopy have implemented a number of initiatives including the 'Improving Safety and Reducing Error in Endoscopy' (ISREE) strategy. Within this, simulation training in human factors and Endoscopic Non-Technical Skills (ENTS) is being developed. Across healthcare, simulation training has been shown to improve team skills and patient outcomes. Although the literature is sparse, integrated and in situ simulation modalities have shown promise in endoscopy. Outcomes demonstrate improved individual and team performance and development of skills that aid clinical practice. Additionally, the use of simulation training to detect latent errors in the working environment is of significant value in reducing error and preventing harm. Implementation of simulation training at local and regional levels can be successfully achieved with collaboration between organisational, educational and clinical leads. Nationally, simulation strategies are a key aspect of the ISREE strategy to improve ENTS training. These may include integration of simulation into current training or development of novel simulation-based curricula. However used, it is evident that simulation training is an important tool in developing safer endoscopy.
RESUMO
Paralytic shellfish toxins (PSTs) in bivalve molluscs represent a public health risk and are controlled via compliance with a regulatory limit of 0.8 mg saxitoxin (STX)â 2HCl equivalents per kilogram of shellfish meat (eq/kg). Shellfish industries would benefit from the use of rapid immunological screening tests for PSTs to be used for regulation, but to date none have been fully validated. An interlaboratory study involving 16 laboratories was performed to determine the suitability of the Neogen test to detect PSTs in mussels and oysters. Participants performed the standard protocol recommended by the manufacturer and a modified protocol with a conversion step to improve detection of gonyautoxin 1&4. The statistical analysis showed that the protocols had good homogeneity across all laboratories, with satisfactory repeatability, laboratory, and reproducibility variation near the regulatory level. The mean probability of detection (POD) at 0.8 mg STXâ 2HCl eq/kg using the standard protocol in mussels and oysters was 0.966 and 0.997, respectively, and 0.968 and 0.966 using the modified protocol. The estimated LOD in mussels was 0.316 mg STXâ 2HCl eq/kg with the standard and 0.682 mg STXâ 2HCl eq/kg with the modified protocol, and 0.710 and 0.734 mg STXâ 2HCl eq/kg for oysters, respectively. The Neogen test may be acceptable for regulatory purposes for oysters in accordance with European Commission directives in which the standard protocol provides, at the regulatory level, a probability of a negative response of 0.033 on 95% of occasions. Its use for mussels is less consistent at the regulatory level due to the wide prediction interval around the POD.
Assuntos
Toxinas Marinhas/análise , Saxitoxina/análogos & derivados , Animais , Crassostrea/química , Dinoflagellida , Imunoensaio/métodos , Limite de Detecção , Toxinas Marinhas/imunologia , Toxinas Marinhas/isolamento & purificação , Mytilus/química , Kit de Reagentes para Diagnóstico , Saxitoxina/análise , Saxitoxina/imunologia , Saxitoxina/isolamento & purificaçãoRESUMO
BACKGROUND: Non-small cell lung cancer (NSCLC) remains a highly lethal disease worldwide and research for more effective treatment strategies is ongoing. Identification of molecular prognostic and predictive markers remains under investigation with results that are often conflicting. PATIENTS AND METHODS: Seventy-three patients (n= 73) with stage IB-IIIA completely resected NSCLC who were postoperatively treated with 6 cycles of paclitaxel and carboplatin from July 1998 to September 2002 took part in this study. Most stage IIIA patients subsequently received adjuvant radiotherapy. Cyclooxygenase-2 (COX-2), vascular endorhelial growth factor (VEGF), dihydrodiol dehydrogenase (DDH), receptor-binding cancer antigen expressed on SiSo cells (RCAS-1) and epidermic growth factor receptor (EGFR/HER-1) expression were assessed immunohistochemically; Heregulin family (HER1-4), VEGF and p53 were analysed by RT-PCR. RESULTS: Totally, 61 (84%) men and 12 (16%) women with median age of 63 years and median PS of 0 were included in the study. There were 18 stage IB, 29 stage II and 26 stage IIIA patients. Sixty-seven samples were available for immunohistohemistry. COX-2 expression was detected in 24 patients (36%), VEGF in 14 (21%), RCAS1 in 31 (46%), DDH in 15 (22%). For EGFR, only 58 samples were evaluated, 13 of which were positive (22%). Messenger RNA expression data was only available for 60 patients; VEGF was detected in 32 (53%), p53 in 30 (50%), EGFR in 35 (58%), HER2 in 4 (7%) and HER3 in 19 (32%). HER4 was not detected in any sample. In the Cox analysis for overall survival (OS) and disease-free survival (DFS), none of the factors evaluated by IHC or RT-PCR reached statistical significance. CONCLUSION: Even though the biomarkers tested are expressed in a significant proportion of lung tumors, none of them was found to be of prognostic significance in patients with NSCLC.