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1.
J Biol Chem ; 299(12): 105459, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37977222

RESUMO

The collagen IVα345 (Col-IVα345) scaffold, the major constituent of the glomerular basement membrane (GBM), is a critical component of the kidney glomerular filtration barrier. In Alport syndrome, affecting millions of people worldwide, over two thousand genetic variants occur in the COL4A3, COL4A4, and COL4A5 genes that encode the Col-IVα345 scaffold. Variants cause loss of scaffold, a suprastructure that tethers macromolecules, from the GBM or assembly of a defective scaffold, causing hematuria in nearly all cases, proteinuria, and often progressive kidney failure. How these variants cause proteinuria remains an enigma. In a companion paper, we found that the evolutionary emergence of the COL4A3, COL4A4, COL4A5, and COL4A6 genes coincided with kidney emergence in hagfish and shark and that the COL4A3 and COL4A4 were lost in amphibians. These findings opened an experimental window to gain insights into functionality of the Col-IVα345 scaffold. Here, using tissue staining, biochemical analysis and TEM, we characterized the scaffold chain arrangements and the morphology of the GBM of hagfish, shark, frog, and salamander. We found that α4 and α5 chains in shark GBM and α1 and α5 chains in amphibian GBM are spatially separated. Scaffolds are distinct from one another and from the mammalian Col-IVα345 scaffold, and the GBM morphologies are distinct. Our findings revealed that the evolutionary emergence of the Col-IVα345 scaffold enabled the genesis of a compact GBM that functions as an ultrafilter. Findings shed light on the conundrum, defined decades ago, whether the GBM or slit diaphragm is the primary filter.


Assuntos
Colágeno Tipo IV , Membrana Basal Glomerular , Mamíferos , Animais , Anuros , Colágeno Tipo IV/classificação , Colágeno Tipo IV/genética , Colágeno Tipo IV/metabolismo , Membrana Basal Glomerular/química , Membrana Basal Glomerular/metabolismo , Membrana Basal Glomerular/fisiologia , Feiticeiras (Peixe) , Mamíferos/genética , Mamíferos/metabolismo , Mamíferos/fisiologia , Tubarões , Especificidade da Espécie , Urodelos
2.
Cytotherapy ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38819362

RESUMO

Chimeric antigen receptor cell therapy is a successful immunotherapy for the treatment of blood cancers. However, hurdles in their manufacturing remain including efficient isolation and purification of the T-cell starting material. Herein, we describe a one-step separation based on inertial spiral microfluidics for efficient enrichment of T-cells in B-cell acute lymphoblastic leukemia (ALL) and B-cell chronic lymphocytic leukemia patient's samples. In healthy donors used to optimize the process, the lymphocyte purity was enriched from 65% (SD ± 0.2) to 91% (SD ± 0.06) and T-cell purity was enriched from 45% (SD ± 0.1) to 73% (SD ± 0.02). Leukemic samples had higher starting B-cells compared to the healthy donor samples. Efficient enrichment and recovery of lymphocytes and T-cells were achieved in ALL samples with B-cells, monocytes and leukemic blasts depleted by 80% (SD ± 0.09), 89% (SD ± 0.1) and 74% (SD ± 0.09), respectively, and a 70% (SD ± 0.1) T-cell recovery. Chronic lymphocytic leukemia samples had lower T-cell numbers, and the separation process was less efficient compared to the ALL. This study demonstrates the use of inertial microfluidics for T-cell enrichment and depletion of B-cell blasts in ALL, suggesting its potential to address a key bottleneck of the chimeric antigen receptor-T manufacturing workflow.

3.
PLoS Pathog ; 17(2): e1009234, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33600433

RESUMO

Environmental temperature is a key factor driving various biological processes, including immune defenses and host-pathogen interactions. Here, we evaluated the effects of environmental temperature on the pathogenicity of the emerging fungal pathogen, Batrachochytrium salamandrivorans (Bsal), using controlled laboratory experiments, and measured components of host immune defense to identify regulating mechanisms. We found that adult and juvenile Notophthalmus viridescens died faster due to Bsal chytridiomycosis at 14°C than at 6 and 22°C. Pathogen replication rates, total available proteins on the skin, and microbiome composition likely drove these relationships. Temperature-dependent skin microbiome composition in our laboratory experiments matched seasonal trends in wild N. viridescens, adding validity to these results. We also found that hydrophobic peptide production after two months post-exposure to Bsal was reduced in infected animals compared to controls, perhaps due to peptide release earlier in infection or impaired granular gland function in diseased animals. Using our temperature-dependent susceptibility results, we performed a geographic analysis that revealed N. viridescens populations in the northeastern United States and southeastern Canada are at greatest risk for Bsal invasion, which shifted risk north compared to previous assessments. Our results indicate that environmental temperature will play a key role in the epidemiology of Bsal and provide evidence that temperature manipulations may be a viable disease management strategy.


Assuntos
Batrachochytrium/patogenicidade , Micoses/imunologia , Notophthalmus viridescens/imunologia , Estações do Ano , Pele/imunologia , Animais , Micoses/epidemiologia , Micoses/microbiologia , Notophthalmus viridescens/microbiologia , Pele/microbiologia , Temperatura
4.
Faraday Discuss ; 242(0): 193-211, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36189732

RESUMO

A number of Pd based materials have been synthesised and evaluated as catalysts for the conversion of carbon dioxide and hydrogen to methanol, a useful platform chemical and hydrogen storage molecule. Monometallic Pd catalysts show poor methanol selectivity, but this is improved through the formation of Pd alloys, with both PdZn and PdGa alloys showing greatly enhanced methanol productivity compared with monometallic Pd/Al2O3 and Pd/TiO2 catalysts. Catalyst characterisation shows that the 1 : 1 ß-PdZn alloy is present in all Zn containing post-reaction samples, including PdZn/Ga2O3, with the Pd2Ga alloy formed for the Pd/Ga2O3 sample. The heat of mixing was calculated for a variety of alloy compositions with high values determined for both PdZn and Pd2Ga alloys, at ca. -0.6 eV per atom and ca. -0.8 eV per atom, respectively. However, ZnO is more readily reduced than Ga2O3, providing a possible explanation for the preferential formation of the PdZn alloy, rather than PdGa, when in the presence of Ga2O3.

5.
BMC Public Health ; 23(1): 2265, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978506

RESUMO

BACKGROUND: The 2022-23 mpox epidemic is the first-time sustained community transmission had been reported in countries without epidemiological links to endemic areas. During that period, the outbreak almost exclusively affected sexual networks of gay, bisexual, or other men who have sex with men (GBMSM) and people living with HIV. In efforts to control transmission, multiple public health measures were implemented, including vaccination, contact tracing and isolation. This study examines knowledge, attitudes, and perceptions of mpox among a sample of GBMSM during the 2022-23 outbreak in the UK, including facilitators for and barriers to the uptake of public health measures. METHODS: Interviews were conducted with 44 GBMSM between May and December 2022. Data were analysed using reflexive thematic analysis. Positive and negative comments pertaining to public health measures were collated in a modified version of a 'table of changes' to inform optimisations to public health messages and guidance. RESULTS: Most interviewees were well informed about mpox transmission mechanisms and were either willing to or currently adhering to public health measures, despite low perceptions of mpox severity. Measures that aligned with existing sexual health practices and norms were considered most acceptable. Connections to GBMSM networks and social media channels were found to increase exposure to sexual health information and norms influencing protective behaviours. Those excluded or marginalized from these networks found some measures challenging to perform or adhere to. Although social media was a key mode of information sharing, there were preferences for timely information from official sources to dispel exaggerated or misleading information. CONCLUSIONS: There are differential needs, preferences, and experiences of GBMSM that limit the acceptability of some mitigation and prevention measures. Future public health interventions and campaigns should be co-designed in consultation with key groups and communities to ensure greater acceptability and credibility in different contexts and communities.


Assuntos
Infecções por HIV , Mpox , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Infecções por HIV/prevenção & controle , Saúde Pública , Reino Unido
6.
BMC Public Health ; 23(1): 2074, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872611

RESUMO

BACKGROUND: During the early "containment" phase of the COVID-19 response in England (January-March 2020), contact tracing was managed by Public Health England (PHE). Adherence to self-isolation during this phase and how people were making those decisions has not previously been determined. The aim of this study was to gain a better understanding of decisions around adherence to self-isolation during the first phase of the COVID-19 response in England. METHODS: A mixed-methods cross sectional study was conducted, including an online survey and qualitative interviews. The overall pattern of adherence was described as never leaving home, leaving home for lower-contact reasons and leaving home for higher-contact reasons. Fisher's exact test was used to test associations between adherence and potentially predictive binary factors. Factors showing evidence of association overall were then considered in relation to the three aspects of adherence individually. Qualitative data were analysed using inductive thematic analysis. RESULTS: Of 250 respondents who were advised to self-isolate, 63% reported not leaving home at all during their isolation period, 20% reported leaving only for lower-contact activities (dog walking or exercise) and 16% reported leaving for higher-contact, and therefore higher-risk, reasons. Factors associated with adherence to never going out included: the belief that following isolation advice would save lives, experiencing COVID-19 symptoms, being advised to stay in their room, having help from outside and having regular contact by text message from PHE. Factors associated with non-adherence included being angry about the advice to isolate, being unable to get groceries delivered and concerns about losing touch with friends and family. Interviews highlighted that a sense of duty motivated people to adhere to isolation guidance and where people did leave their homes, these decisions were based on rational calculations of the risk of transmission - people would only leave their homes when they thought they were unlikely to come into contact with others. CONCLUSIONS: Understanding adherence to isolation and associated reasoning during the early stages of the pandemic is essential to pandemic preparedness for future emerging infectious disease outbreaks. Individuals make complex decisions around adherence by calibrating transmission risks, therefore treating adherence as binary should be avoided.


Assuntos
COVID-19 , Humanos , Animais , Cães , COVID-19/epidemiologia , Estudos Transversais , Pandemias , Inglaterra/epidemiologia , Saúde Pública
7.
Int J Mol Sci ; 24(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36614239

RESUMO

Fundamental knowledge about cell-surface interactions can be applied in the development of wound dressings and scaffolds to encourage wounds to heal. As surfaces produced with acid-functionalised monomers encourage keratinocyte adhesion, proliferation and migration, whilst amine functionalisation enhances fibroblast proliferation and migration in vitro, standard care wound dressings were plasma-coated with either acrylic acid or allylamine and applied to 6 mm excisional wounds on the backs of mice to test their effectiveness in vivo. At day 3, the rate of wound healing was increased in mice treated with dressings that were plasma-coated with allylamine compared to uncoated dressings, with a significantly reduced wound area. However, healing may be impaired following prolonged treatment with allylamine-functionalised dressings, with delayed re-epithelialisation and increased cellularisation of the wound site at later timepoints. Acrylic acid functionalisation, however, offered no early improvement in wound healing, but wounds treated with these dressings displayed increased collagen deposition at day 7 post wounding. These results suggest that plasma polymerisation may allow for the development of new dressings which can enhance wound closure by directing cell behaviour, but that the application of these dressings may require a timed approach to enhance specific phases of the wound healing response.


Assuntos
Bandagens , Cicatrização , Camundongos , Animais , Acrilatos/farmacologia , Colágeno
8.
Infect Immun ; 90(3): e0002022, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35130454

RESUMO

Amphibian populations have been declining around the world for more than five decades, and the losses continue. Although causes are complex, major contributors to these declines are two chytrid fungi, Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans, which both cause the disease termed chytridiomycosis. Previously, we showed that B. dendrobatidis impedes amphibian defenses by directly inhibiting lymphocytes in vitro and in vivo by release of soluble metabolites, including kynurenine (KYN), methylthioadenosine (MTA), and spermidine (SPD). Here, we show that B. salamandrivorans cells and cell-free supernatants also inhibit amphibian lymphocytes as well as a human T cell line. As we have shown for B. dendrobatidis, high-performance liquid chromatography (HPLC) and mass spectrometry revealed that KYN, MTA, and SPD are key metabolites found in the B. salamandrivorans supernatants. Production of inhibitory factors by B. salamandrivorans is limited to mature zoosporangia and can occur over a range of temperatures between 16°C and 26°C. Taken together, these results suggest that both pathogenic Batrachochytrium fungi have evolved similar mechanisms to inhibit lymphocytes in order to evade clearance by the amphibian immune system.


Assuntos
Quitridiomicetos , Animais , Humanos , Anfíbios , Batrachochytrium , Cinurenina/metabolismo , Linfócitos , Espermidina/metabolismo , Urodelos
9.
Transfus Apher Sci ; 61(2): 103412, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35283031

RESUMO

Critically injured persons suffer trauma, hemorrhage, and high mortality. A subset of such patients develops early coagulation dysfunction characterized as acute traumatic coagulopathy (ATC), with a poor prognosis. The mechanisms contributing to ATC remain incompletely understood. Notwithstanding some successes in conducting clinical trials in early traumatic coagulopathy, conducting clinical research in ATC is ethically and logistically challenging. In vitro studies cannot capture the complex pathophysiological interplay between blood, vasculature, and organ systems relevant to ATC. Animal models are therefore vital for understanding ATC and to test interventions. Previous systematic reviews of animal models of ATC covered progress up to 2014. The current review aimed to extend that coverage to the end of 2021. A structured systematic search of MEDLINE/PubMed was carried out and identified 56 relevant publications. Unlike in previous reviews, where pig models predominated, rat and pig models contributed equally (19 studies each), and non-human primate models entered the field. Most studies now featured defined trauma (39 of 56), and hemorrhage controlled by pressure or volume (42 studies), with some documenting that both were necessary to induce ATC. Most studies documented coagulopathy using clotting or viscoelastometric assays and created an endogenous coagulopathy not dependent on iatrogenic dilution. As before, the diversity of species and experimental protocols may limit the translatability of the identified studies. Thus, while animal research has become more aligned to clinical realities since 2014, further efforts are required to unravel ATC mechanisms and enable the prediction and evaluation of optimal clinical interventions.


Assuntos
Transtornos da Coagulação Sanguínea , Ferimentos e Lesões , Animais , Coagulação Sanguínea , Transtornos da Coagulação Sanguínea/etiologia , Modelos Animais de Doenças , Hemorragia , Humanos , Ratos , Suínos , Ferimentos e Lesões/complicações
10.
Intern Med J ; 52(5): 711-716, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34553824

RESUMO

New evidence shows that up to 40% of rheumatoid arthritis (RA) cases are attributable to exposure to potentially modifiable factors. We can now identify people at higher risk of RA (pre-RA) through their family history, risk factors, autoantibodies and symptoms. Counselling these patients to act to modify factors known to be associated with RA risk could prevent the development of RA, and evidence shows that informing individuals of their risk and of ways to reduce it leads to positive behavioural change and is not harmful. This consumer-focussed narrative review is targeted at primary care providers and physicians to describe 11 changes that can be made, based on current evidence linking potentially modifiable factors to RA risk. These evidence-based recommendations are: (i) cease smoking; (ii) reduce exposure to inhaled silica, dusts and occupational risks; (iii) maintain a healthy weight; (iv) increase leisure time physical activity; (v) maintain good dental hygiene; (vi) maximise breastfeeding if able; (vii) maximise dietary quality and avoid high-salt diets; (viii) consume high levels of omega-3 fatty acids and fish; (ix) reduce consumption of sugar-sweetened soft drinks; (x) consume moderate levels of alcohol; and (xi) remain vitamin D replete.


Assuntos
Artrite Reumatoide , Animais , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/prevenção & controle , Autoanticorpos , Dieta , Humanos , Fatores de Risco , Fumar/efeitos adversos
11.
BMC Public Health ; 22(1): 1436, 2022 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-35902818

RESUMO

OBJECTIVES: To assess the quantity and quality of studies using an observational measure of behaviour during the COVID-19 pandemic, and to narratively describe the association between self-report and observational data for behaviours relevant to controlling an infectious disease outbreak. DESIGN: Systematic review and narrative synthesis of observational studies. DATA SOURCES: We searched Medline, Embase, PsychInfo, Publons, Scopus and the UK Health Security Agency behavioural science LitRep database from inception to 17th September 2021 for relevant studies. STUDY SELECTION: We included studies which collected observational data of at least one of three health protective behaviours (hand hygiene, face covering use and maintaining physical distance from others ('social distancing') during the COVID-19 pandemic. Studies where observational data were compared to self-report data in relation to any infectious disease were also included. DATA EXTRACTION AND SYNTHESIS: We evaluated the quality of studies using the NIH quality assessment scale for observational studies, extracted data on sample size, setting and adherence to health protective behaviours, and synthesized results narratively. RESULTS: Of 27,279 published papers on COVID-19 relevant health protective behaviours that included one or more terms relating to hand hygiene, face covering and social distancing, we identified 48 studies that included an objective observational measure. Of these, 35 assessed face covering use, 17 assessed hand hygiene behaviour and seven assessed physical distancing. The general quality of these studies was good. When expanding the search to all infectious diseases, we included 21 studies that compared observational versus self-report data. These almost exclusively studied hand hygiene. The difference in outcomes was striking, with self-report over-estimating observed adherence by up to a factor of five in some settings. In only four papers did self-report match observational data in any domains. CONCLUSIONS: Despite their importance in controlling the pandemic, we found remarkably few studies assessing protective behaviours by observation, rather than self-report, though these studies tended to be of reasonably good quality. Observed adherence tends to be substantially lower than estimates obtained via self-report. Accurate assessment of levels of personal protective behaviour, and evaluation of interventions to increase this, would benefit from the use of observational methods.


Assuntos
COVID-19 , COVID-19/prevenção & controle , Humanos , Controle de Infecções , Pandemias/prevenção & controle , Distanciamento Físico , Autorrelato
12.
BMC Public Health ; 22(1): 475, 2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35272652

RESUMO

BACKGROUND: Behaviour is key to suppressing the COVID-19 pandemic. Maintaining behaviour change can be difficult. We investigated engagement with hand cleaning, reducing the number of outings, and wearing a face covering over the course of the pandemic. METHODS: We used a series of 64 cross-sectional surveys between 10 February 2020 and 20 January 2022 (n ≈ 2000 per wave). Surveys investigated uptake of hand cleaning behaviours, out of home activity (England only, n ≈ 1700 per wave) and wearing a face covering (England only, restricted to those who reported going out shopping in the last week, n ≈ 1400 per wave). RESULTS: Reported hand cleaning has been high throughout the pandemic period (85 to 90% of participants consistently reporting washing their hands thoroughly and regularly with soap and water frequently or very frequently). Out of home activity has mirrored the easing and re-introduction of restrictive measures. Total number of outings were higher in the second national lockdown than in the first and third lockdowns. Wearing a face covering increased steadily between April to August 2020, plateauing until the end of measurement in May 2021, with approximately 80% of those who had been out shopping in the previous week reporting wearing a face covering frequently or very frequently. CONCLUSIONS: Engagement with protective behaviours increased at the start of the pandemic and has remained high since. The greatest variations in behaviour reflected changes to Government rules. Despite the duration of restrictions, people have continued to adopt personal protective behaviours that were intended to prevent the spread of COVID-19.


Assuntos
COVID-19 , Influenza Humana , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Estudos Transversais , Humanos , Influenza Humana/epidemiologia , Pandemias/prevenção & controle , SARS-CoV-2 , Reino Unido/epidemiologia
13.
BMC Public Health ; 22(1): 2145, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36418978

RESUMO

BACKGROUND: The national shielding programme was introduced by UK Government at the beginning of the COVID-19 pandemic, with individuals identified as clinically extremely vulnerable (CEV) offered advice and support to stay at home and avoid all non-essential contact. This study aimed to explore the impact and responses of "shielding" on the health and wellbeing of CEV individuals in Southwest England during the first COVID-19 lockdown. METHODS: A two-stage mixed methods study, including a structured survey (7 August-23 October 2020) and semi-structured telephone interviews (26 August-30 September 2020) with a sample of individuals who had been identified as CEV and advised to "shield" by Bristol, North Somerset & South Gloucestershire (BNSSG) Clinical Commissioning Group (CCG). RESULTS: The survey was completed by 203 people (57% female, 54% > 69 years, 94% White British, 64% retired) in Southwest England identified as CEV by BNSSG CCG. Thirteen survey respondents participated in follow-up interviews (53% female, 40% > 69 years, 100% White British, 61% retired). Receipt of 'official' communication from NHS England or General Practitioner (GP) was considered by participants as the legitimate start of shielding. 80% of survey responders felt they received all relevant advice needed to shield, yet interviewees criticised the timing of advice and often sought supplementary information. Shielding behaviours were nuanced, adapted to suit personal circumstances, and waned over time. Few interviewees received community support, although food boxes and informal social support were obtained by some. Worrying about COVID-19 was common for survey responders (90%). Since shielding had begun, physical and mental health reportedly worsened for 35% and 42% of survey responders respectively. 21% of survey responders scored ≥ 10 on the PHQ-9 questionnaire indicating possible depression and 15% scored ≥ 10 on the GAD-7 questionnaire indicating possible anxiety. CONCLUSIONS: This research highlights the difficulties in providing generic messaging that is applicable and appropriate given the diversity of individuals identified as CEV and the importance of sharing tailored and timely advice to inform shielding decisions. Providing messages that reinforce self-determined action and assistance from support services could reduce the negative impact of shielding on mental health and feelings of social isolation.


Assuntos
COVID-19 , Clínicos Gerais , Humanos , Feminino , Masculino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias , Controle de Doenças Transmissíveis , Clínicos Gerais/psicologia , Saúde Mental
14.
Emerg Med J ; 39(2): 100-105, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34848560

RESUMO

BACKGROUND: Healthcare workers (HCWs) are frontline responders to emergency infectious disease outbreaks such as COVID-19. To avoid the rapid spread of disease, adherence to protective measures is paramount. We investigated rates of correct use of personal protective equipment (PPE), hand hygiene and physical distancing in UK HCWs who had been to their workplace at the start of the COVID-19 pandemic and factors associated with adherence. METHODS: We used an online cross-sectional survey of 1035 UK healthcare professionals (data collected 12-16 June 2020). We excluded those who had not been to their workplace in the previous 6 weeks, leaving us with a sample size of 831. Respondents were asked about their use of PPE, hand hygiene and physical distancing in the workplace. Frequency of uptake was reported descriptively; adjusted logistic regressions were used to separately investigate factors associated with adherence to use of PPE, maintaining good hand hygiene and physical distancing from colleagues. RESULTS: Adherence to personal protective measures was suboptimal (PPE use: 80.0%, 95% CI 77.3 to 82.8; hand hygiene: 67.8%, 95% CI 64.6 to 71.0; coming into close contact with colleagues: 74.7%, 95% CI 71.7 to 77.7). Adherence to PPE use was associated with having received training about health and safety in the workplace for COVID-19, greater perceived social pressure to adopt the behaviour and availability of PPE. Non-adherence was associated with fatalism about COVID-19 and greater perceived difficulty of adopting protective measures. Workplace design using markings to facilitate distancing was associated with adherence to physical distancing. CONCLUSIONS: Uptake of personal protective behaviours among UK HCWs at the start of the pandemic was variable. Factors associated with adherence provide insight into ways to support HCWs to adopt personal protective behaviours, such as ensuring that adequate PPE is available and designing workplaces to facilitate physical distancing.


Assuntos
COVID-19 , Pandemias , Estudos Transversais , Pessoal de Saúde , Humanos , SARS-CoV-2 , Reino Unido
15.
Lancet ; 395(10227): 912-920, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32112714

RESUMO

The December, 2019 coronavirus disease outbreak has seen many countries ask people who have potentially come into contact with the infection to isolate themselves at home or in a dedicated quarantine facility. Decisions on how to apply quarantine should be based on the best available evidence. We did a Review of the psychological impact of quarantine using three electronic databases. Of 3166 papers found, 24 are included in this Review. Most reviewed studies reported negative psychological effects including post-traumatic stress symptoms, confusion, and anger. Stressors included longer quarantine duration, infection fears, frustration, boredom, inadequate supplies, inadequate information, financial loss, and stigma. Some researchers have suggested long-lasting effects. In situations where quarantine is deemed necessary, officials should quarantine individuals for no longer than required, provide clear rationale for quarantine and information about protocols, and ensure sufficient supplies are provided. Appeals to altruism by reminding the public about the benefits of quarantine to wider society can be favourable.


Assuntos
Infecções por Coronavirus/prevenção & controle , Pneumonia Viral/prevenção & controle , Quarentena , Estresse Psicológico , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Financiamento Pessoal , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Saúde Pública , Quarentena/economia , Quarentena/psicologia , Condições Sociais , Estigma Social , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/prevenção & controle
16.
Small ; 17(16): e2007221, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33629821

RESUMO

The formation of highly active and stable acetylene hydrochlorination catalysts is of great industrial importance. The successful replacement of the highly toxic mercuric chloride catalyst with gold has led to a flurry of research in this area. One key aspect, which led to the commercialization of the gold catalyst is the use of thiosulphate as a stabilizing ligand. This study investigates the use of a range of sulfur containing compounds as promoters for production of highly active Au/C catalysts. Promotion is observed across a range of metal sulfates, non-metal sulfates, and sulfuric acid treatments. This observed enhancement can be optimized by careful consideration of either pre- or post-treatments, concentration of dopants used, and modification of washing steps. Pre-treatment of the carbon support with sulfuric acid (0.76 m) resulted in the most active Au/C in this series with an acetylene conversion of ≈70% at 200 °C.


Assuntos
Acetileno , Ouro , Carbono , Catálise , Enxofre
17.
Faraday Discuss ; 229: 108-130, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33650598

RESUMO

The production of methanol from glycerol over a basic oxide, such as MgO, using high reaction temperatures (320 °C) is a promising new approach to improving atom efficiency in the production of biofuels. The mechanism of this reaction involves the homolytic cleavage of the C3 feedstock, or its dehydration product hydroxyacetone, to produce a hydroxymethyl radical species which can then abstract an H atom from other species. Obtaining a detailed reaction mechanism for this type of chemistry is difficult due to the large number of products present when the system is operated at high conversions. In this contribution we show how DFT based modelling studies can provide new insights into likely reaction pathways, in particular the source of H atoms for the final step of converting hydroxymethyl radicals to methanol. We show that water is unlikely to be important in this stage of the process, C-H bonds of C2 and C3 species can give an energetically favourable pathway and that the disproportionation of hydroxymethyl radicals to methanol and formaldehyde produces a very favourable route. Experimental analysis of reaction products confirms the presence of formaldehyde. The calculations presented in this work also provide new insight into the role of the catalyst surface in the reaction showing that the base sites of the MgO(100) are able to deprotonate hydroxymethyl radicals but not methanol itself. In carrying out the calculations we also show how periodic DFT and QM/MM approaches can be used together to obtain a rounded picture of molecular adsorption to surfaces and homolytic bond cleavage which are both central to the reactions studied.

18.
J Anim Ecol ; 90(2): 542-554, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33179786

RESUMO

Accurately predicting the impacts of climate change on wildlife health requires a deeper understanding of seasonal rhythms in host-pathogen interactions. The amphibian pathogen, Batrachochytrium dendrobatidis (Bd), exhibits seasonality in incidence; however, the role that biological rhythms in host defences play in defining this pattern remains largely unknown. The aim of this study was to examine whether host immune and microbiome defences against Bd correspond with infection risk and seasonal fluctuations in temperature and humidity. Over the course of a year, five populations of Southern leopard frogs (Rana [Lithobates] sphenocephala) in Tennessee, United States, were surveyed for host immunity, microbiome and pathogen dynamics. Frogs were swabbed for pathogen load and skin bacterial diversity and stimulated to release stored antimicrobial peptides (AMPs). Secretions were analysed to estimate total hydrophobic peptide concentrations, presence of known AMPs and effectiveness of Bd growth inhibition in vitro. The diversity and proportion of bacterial reads with a 99% match to sequences of isolates known to inhibit Bd growth in vitro were used as an estimate of predicted anti-Bd function of the skin microbiome. Batrachochytrium dendrobatidis dynamics followed the expected seasonal fluctuations-peaks in cooler months-which coincided with when host mucosal defences were most potent against Bd. Specifically, the concentration and expression of stored AMPs cycled synchronously with Bd dynamics. Although microbiome changes followed more linear trends over time, the proportion of bacteria that can function to inhibit Bd growth was greatest when risk of Bd infection was highest. We interpret the increase in peptide storage in the fall and the shift to a more anti-Bd microbiome over winter as a preparatory response for subsequent infection risk during the colder periods when AMP synthesis and bacterial growth is slow and pathogen pressure from this cool-adapted fungus is high. Given that a decrease in stored AMP concentrations as temperatures warm in spring likely means greater secretion rates, the subsequent decrease in prevalence suggests seasonality of Bd in this host may be in part regulated by annual immune rhythms, and dominated by the effects of temperature.


Assuntos
Quitridiomicetos , Micoses , Animais , Batrachochytrium , Micoses/veterinária , Rana pipiens , Tennessee
19.
Wound Repair Regen ; 29(3): 380-392, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33655577

RESUMO

Stem cells have been shown to have potential as a new therapy for burns and promote wound healing through decreasing inflammation and increasing angiogenesis. Multipotent adult progenitor cells (MAPC® cells) are a subpopulation of bone marrow-derived stem cells with outstanding self-renewal and differentiation capacity. MAPC cells also secrete a wide range of cytokines which can affect cellular activities. This article aimed to examine the effects of MAPC cells treatment on burn injury repair using a mouse model of partial thickness burn injury. The immunomodulatory effect of MAPC cells was investigated in vitro using a simultaneous T-cell proliferation assay. Partial thickness burns were created on the dorsal surface of mice and MAPC cells were administered via intradermal injection to the wound margins 24 h post-burn injury. The burn tissues were analysed macroscopically to determine wound area and histologically assessed to determine wound width and rate of re-epithelialisation. Immunohistochemistry and ELISA were employed to assess cell proliferation, inflammation and angiogenesis and collagen deposition in the burn area. MAPC cells inhibit the proliferation of stimulated T cells in culture. Burns intradermally injected with MAPC cells showed a significant reduction in the macroscopic wound area, histologic wound width and had an increased rate of re-epithelialisation. Immunohistochemistry and ELISA analysis of burn tissues showed dampened inflammation evidenced by a reduction in neutrophilic infiltration and modulation of inflammatory cytokines. Angiogenesis within the burn area was also improved in MAPC cell treated mice. However, no significant effect of MAPC cell treatment was observed on extracellular matrix production. Treatment of burns with MAPC cells improved burn injury repair with reduced time to healing, decreased inflammation and increased angiogenesis. These findings demonstrate the promising effects of MAPC cells on burn injury repair and suggest MAPC cells as a candidate source for clinical cell therapies.


Assuntos
Queimaduras , Cicatrização , Animais , Queimaduras/terapia , Inflamação , Camundongos , Reepitelização , Células-Tronco
20.
J Public Health (Oxf) ; 43(3): 508-516, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-33559682

RESUMO

BACKGROUND: Evidence highlights the disproportionate impact of measures that have been introduced to reduce the spread of coronavirus on individuals from Black, Asian and minority ethnic (BAME) communities, and among those on a low income. An understanding of barriers to adherence in these populations is needed. In this qualitative study, we examined the patterns of adherence to mitigation measures and reasons underpinning these behaviors. METHODS: Semi-structured interviews were conducted with 20 participants from BAME and low-income White backgrounds. The topic guide was designed to explore how individuals are adhering to social distancing and self-isolation during the pandemic and to explore the reasons underpinning this behavior. RESULTS: We identified three categories of adherence to lockdown measures: (i) caution-motivated super-adherence (ii) risk-adapted partial-adherence and (iii) necessity-driven partial-adherence. Decisions about adherence considered potential for exposure to the virus, ability to reduce risk through use of protective measures and perceived importance of/need for the behavior. CONCLUSIONS: This research highlights a need for a more nuanced understanding of adherence to lockdown measures. Provision of practical and financial support could reduce the number of people who have to engage in necessity-driven partial-adherence. More evidence is required on population level risks of people adopting risk-adapted partial-adherence.


Assuntos
COVID-19 , Controle de Doenças Transmissíveis , Humanos , Pandemias , Pesquisa Qualitativa , SARS-CoV-2
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