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1.
Nature ; 574(7776): 117-121, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31534227

RESUMO

Immediately after birth, newborn babies experience rapid colonization by microorganisms from their mothers and the surrounding environment1. Diseases in childhood and later in life are potentially mediated by the perturbation of the colonization of the infant gut microbiota2. However, the effects of delivery via caesarean section on the earliest stages of the acquisition and development of the gut microbiota, during the neonatal period (≤1 month), remain controversial3,4. Here we report the disrupted transmission of maternal Bacteroides strains, and high-level colonization by opportunistic pathogens associated with the hospital environment (including Enterococcus, Enterobacter and Klebsiella species), in babies delivered by caesarean section. These effects were also seen, to a lesser extent, in vaginally delivered babies whose mothers underwent antibiotic prophylaxis and in babies who were not breastfed during the neonatal period. We applied longitudinal sampling and whole-genome shotgun metagenomic analysis to 1,679 gut microbiota samples (taken at several time points during the neonatal period, and in infancy) from 596 full-term babies born in UK hospitals; for a subset of these babies, we collected additional matched samples from mothers (175 mothers paired with 178 babies). This analysis demonstrates that the mode of delivery is a significant factor that affects the composition of the gut microbiota throughout the neonatal period, and into infancy. Matched large-scale culturing and whole-genome sequencing of over 800 bacterial strains from these babies identified virulence factors and clinically relevant antimicrobial resistance in opportunistic pathogens that may predispose individuals to opportunistic infections. Our findings highlight the critical role of the local environment in establishing the gut microbiota in very early life, and identify colonization with antimicrobial-resistance-containing opportunistic pathogens as a previously underappreciated risk factor in hospital births.


Assuntos
Cesárea/efeitos adversos , Microbioma Gastrointestinal , Doenças do Recém-Nascido/microbiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Infecções Oportunistas/congênito , Infecções Oportunistas/microbiologia , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/etiologia , Infecções Oportunistas/etiologia , Gravidez
2.
Biophys J ; 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39344141

RESUMO

We demonstrate the use of multiscale polymer modeling to quantitatively predict DNA linear dichroism (LD) in shear flow. LD is the difference in absorption of light polarized along two perpendicular axes and has long been applied to study biopolymer structure and drug-biopolymer interactions. As LD is orientation dependent, the sample must be aligned in order to measure a signal. Shear flow via a Couette cell can generate the required orientation; however, it is challenging to separate the LD due to changes in polymer conformation from specific interactions, e.g., drug-biopolymer. In this study, we have applied a combination of Brownian dynamics and equilibrium Monte Carlo simulations to accurately predict polymer alignment, and hence flow LD, at modest computational cost. As the optical and conformational contributions to the LD can be explicitly separated, our findings allow for enhanced quantitative interpretation of LD spectra through the use of an in silico model to capture conformational changes. Our model requires no fitting and only five input parameters: the DNA contour length, persistence length, optical factor, solvent quality, and relaxation time, all of which have been well characterized in prior literature. The method is sufficiently general to apply to a wide range of biopolymers beyond DNA, and our findings could help guide the search for new pharmaceutical drug targets via flow LD.

3.
Anal Chem ; 96(9): 3810-3816, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38385756

RESUMO

Circularly polarized luminescent (CPL) systems have a plethora of potential applications owing to their interesting excited-state properties. However, the progress in developing new chiral luminescence systems is significantly hindered by the lack of available instrumentation for the broader chemistry and materials science community to perform routine, reproducible measurements of chiral spectroscopies. In this work, we present data from an easy-to-use custom-built instrument based on a Jasco circular dichroism (CD) spectropolarimeter coupled with a CPL emission monochromator (CD/CPL hybrid system). The hybrid system measures CPL, fluorescence, CD, and absorbance on the same part of the sample without the need to move between the CD and CPL measurements. The instrument uses a xenon arc lamp as the light source, enabling a wide range of excitation wavelengths to support flexible development of new molecules and materials. Data obtained and presented for camphor, ruthenium metal complexes, the peptide gramicidin, and a DNA-ligand (4',6-diamidino-2-phenylindole, DAPI) system in this work highlight the ease of use and reproducibility of the results. The g-factors for CD and CPL obtained for the different compounds are shown to be the same for isolated transitions and some examples of how to use variations of g-factors with wavelength are demonstrated. The reliable and excellent benchmark results obtained from a custom-built commercial wavelength scanning CPL/CD hybrid instrument open up new avenues for the broader chemical and materials science community to intensify research on chiral luminescent systems.

4.
Anal Chem ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39255385

RESUMO

Understanding the impact of the manufacturing environment on therapeutic monoclonal antibody (mAb) structures requires new process analytical technology. Here, we describe the creation of a new reference set for the circular dichroism (CD) spectra of mAbs. Data sets of the highest quality were collected by synchrotron radiation CD for 14 different mAbs in both native and acid-stressed states. Deconvolution of far-UV spectra for the mAb cohort identified two current reference sets (SP175 and SMP180) as assigning accurate secondary structures, irrespective of the analysis program employed. Scrutiny of spectra revealed significant variation in the far-UV and especially near-UV CD of the 14 mAbs. Two spectral features were found to be sensitive to changes in solution pH, i.e., the far-UV positive peak at 201-202 nm and the near-UV negative exciton couplet around 230-240 nm. The latter feature offers attractive possibilities for in-line CD-based monitoring of the mAb structure during manufacture.

5.
HIV Med ; 25(6): 746-753, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38433523

RESUMO

OBJECTIVES: This qualitative sub-study aimed to explore how cisgender gay, bisexual, and other men who have sex with men (cis-GBMSM) and transgender people who reported non-consensual sex (NCS) accessed health care services, what barriers they faced, and how this experience influenced subsequent HIV testing. METHODS: SELPHI is an online randomized controlled trial evaluating both acceptability and efficiency of HIV-self testing among cis-GBMSM and transgender people. Semi-structured interviews were conducted, audio-recorded, transcribed, and analysed through a framework analysis, as a qualitative sub-study. We identified narratives of NCS from interviews and investigated experiences of cis-GBMSM and transgender people accessing health care services following sexual assault. RESULTS: Of 95 participants, 15 (16%) spontaneously reported NCS. Participants reported a broad range of NCS, including partner's coercive behaviours, non-consensual removal of condoms, and rapes. All feared HIV transmission, leading them to test for HIV, underlining a marked lack of awareness of post-exposure prophylaxis (PEP). Most had negative experiences in communicating with reception staff in sexual health clinics following these incidents. A lack of confidentiality and empathy was described in these situations of psychological distress. Clinic visits were primarily focused on testing for HIV and sexually transmitted infection, and generally no specific psychological support was offered. Getting a negative HIV result was a key step in regaining control for people who experienced NCS. CONCLUSIONS: Sexual health care providers should take care to more fully address the issue of NCS with cis-GBMSM and transgender people when it arises. Recognizing and managing the emotional impact of NCS on affected patients would prevent negative experiences and increase confidence in care.


Assuntos
Infecções por HIV , Teste de HIV , Delitos Sexuais , Humanos , Masculino , Adulto , Infecções por HIV/prevenção & controle , Infecções por HIV/diagnóstico , Infecções por HIV/psicologia , Delitos Sexuais/psicologia , Adulto Jovem , Pessoa de Meia-Idade , Pesquisa Qualitativa , Minorias Sexuais e de Gênero/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Pessoas Transgênero/psicologia , Entrevistas como Assunto , Homossexualidade Masculina/psicologia , Adolescente
6.
Ann Allergy Asthma Immunol ; 132(4): 497-504.e3, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38036031

RESUMO

BACKGROUND: Widening of subtropical climate zones globally and increasing grass-pollen exposure provide the impetus for developing a more precise and accessible diagnosis of allergy. OBJECTIVE: To evaluate the utility of recombinant allergen components of Panicoideae and Chloridoideae pollens for specific IgE testing in a rapid, point-of-care device. METHODS: Recombinant (r) Pas n 1 and Cyn d 1 were expressed, purified, and tested in the nanofluidic device for measuring serum specific IgE (spIgE) in a well-characterized Australian cohort. Concentrations and classes of spIgE to rPas n 1 and rCyn d 1, and total IgE were compared with skin prick test results and spIgE with grass pollen. RESULTS: Correlations between commercial and academic laboratories for 21 sera were high for rPas n 1 spIgE (r = 0.695) and total IgE (r = 0.945). Higher spIgE to rPas n 1 and rCyn d 1 fluorescence was detected in the patients with grass-pollen allergy and with clinician-diagnosed allergic rhinitis (n = 134) than in participants with other allergies (n = 49) or no allergies (n = 23). Correlation between spIgE concentrations to rPas n 1 (r = 0.679) and rCyn d 1 (r = 0.548), with Bahia and Bermuda grass-pollen spIgE, respectively, was highly significant (p<0.0001). The positive/negative predictive agreements of spIgE classes for rPas n 1 (73%/82.5%) and rCyn d 1 (67.8%/66.3%) between the nanofluidic and ImmunoCAP measurements for Bahia and Bermuda grass pollen, respectively, were substantial. CONCLUSION: Point-of-care nanofluidic tests for spIgE to rPas n 1 and rCyn d 1 could increase access to more precise clinical diagnosis for patients with allergies in subtropical regions.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Rinite Alérgica , Humanos , Austrália , Pólen , Alérgenos , Rinite Alérgica/diagnóstico , Imunoglobulina E , Poaceae
7.
Chirality ; 36(4): e23667, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38607651

RESUMO

Fluorescence-detected linear dichroism (FD-LD) enables one to collect linear dichroism spectra for oriented fluorophores in the presence of other absorbing species and light scattering. The experiment proceeds by scanning the excitation wavelength and using a filter to collect only emitted photons from the fluorophore. Thus, it has the potential to give data with enhanced selectivity and quality. By using a synchrotron radiation light source and fluorescence-detection, we show data for a range of fluorophores in different orienting environments. Film and flow-oriented FD-LD spectra were collected down to 170 nm. Even for flow-oriented liposomes, we have data collected down to 210 nm. For strongly scattering samples, for example, liposomes, FD-LD has the clear advantage that scattering is absent for the longer wavelength fluorescence photons. The collimated and smaller beam size of the synchrotron radiation also gives rise to sharper and more well-defined features in the spectra.

8.
BMC Public Health ; 24(1): 1984, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054509

RESUMO

BACKGROUND: Understanding how HIV self-testing (HIVST) can meet the testing needs of gay, bisexual and other men who have sex with men (GBMSM) and trans people whose social networks vary is key to upscaling HIVST implementation. We aim to develop a contextual understanding of social networks and HIV testing needs among GBMSM (cis and transgender) and trans women in SELPHI (An HIV Self-testing Public Health Intervention), the UK's largest randomised trial on HIVST. METHODS: This study re-analysed qualitative interviews conducted from 2015 to 2020. Forty-three in-person interviews were thematically analysed using the Framework Method. Our analytic matrix inductively categorised participants based on the unmet needs for HIV testing and the extent of social network support. The role of social networks on HIVST behaviour was explored based on individuals' testing trajectories. RESULTS: Four distinct groups were identified based on their unmet testing needs and perceived support from social networks. Optimisation advocates (people with high unmet needs and with high network support, n = 17) strived to tackle their remaining barriers to HIV testing through timely support and empowerment from social networks. Privacy seekers (people with high unmet needs and with low network support, n = 6) prioritised privacy because of perceived stigma. Opportunistic adopters (people with low unmet needs and with high network support, n = 16) appreciated social network support and acknowledged socially privileged lives. Resilient testers (people with low unmet needs and with low network support, n = 4) might hold potentially disproportionate confidence in managing HIV risks without sustainable coping strategies for potential seroconversion. Supportive social networks can facilitate users' uptake of HIVST by: (1) increasing awareness and positive attitudes towards HIVST, (2) facilitating users' initiation into HIVST with timely support and (3) affording participants an inclusive space to share and discuss testing strategies. CONCLUSIONS: Our proposed categorisation may facilitate the development of differentiated person-centred HIVST programmes. HIVST implementers should carefully consider individuals' unmet testing needs and perceived levels of social support, and design context-specific HIVST strategies that link people lacking supportive social networks to comprehensive HIV care.


Assuntos
Infecções por HIV , Pesquisa Qualitativa , Autoteste , Pessoas Transgênero , Humanos , Masculino , Adulto , Feminino , Inglaterra , Infecções por HIV/diagnóstico , Infecções por HIV/psicologia , País de Gales , Pessoas Transgênero/psicologia , Pessoas Transgênero/estatística & dados numéricos , Pessoa de Meia-Idade , Rede Social , Minorias Sexuais e de Gênero/psicologia , Minorias Sexuais e de Gênero/estatística & dados numéricos , Teste de HIV/estatística & dados numéricos , Entrevistas como Assunto , Homossexualidade Masculina/psicologia , Homossexualidade Masculina/estatística & dados numéricos , Apoio Social , Adulto Jovem
9.
HIV Med ; 24(11): 1115-1125, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641541

RESUMO

BACKGROUND: Understanding the health care activity and associated hospital costs of caring for people living with HIV is an important component of assessing the cost effectiveness of new technologies and for budget planning. METHODS: Data collected between 2010 and 2017 from an English HIV treatment centre were combined with national reference costs to estimate the rate of hospital attendances and costs per quarter year, according to demographic and clinical factors. The final dataset included records for 1763 people living with HIV, which was analysed using negative binomial regression models and general estimating equations. RESULTS: People living with HIV experienced an unadjusted average of 0.028 (standard deviation [SD] 0.20) inpatient episodes per quarter, equivalent to one every 9 years, and 1.85 (SD 2.30) outpatient visits per quarter. The unadjusted mean quarterly cost per person with HIV (excluding antiretroviral drug costs) was £439 (SD 604). Outpatient appointments and inpatient episodes accounted for 88% and 6% of total costs, respectively. In adjusted models, low CD4 count was the strongest predictor of inpatient stays and outpatient visits. Low CD4 count and new patient status (having a first visit at the Trust in the last 6 months) were the factors that most increased estimated costs. Associations were weaker or less consistent for demographic factors (age, sex/sexual orientation/ethnicity). Sensitivity analyses suggest that the findings were generally robust to alternative parameter and modelling assumptions. CONCLUSION: A number of factors predicted hospital activity and costs, but CD4 cell count and new patient status were the strongest. The study results can be incorporated into future economic evaluations and budget impact assessments of HIV-related technologies.


Assuntos
Infecções por HIV , Humanos , Masculino , Feminino , Infecções por HIV/tratamento farmacológico , Custos Hospitalares , Dados de Saúde Coletados Rotineiramente , Inglaterra/epidemiologia , Hospitais , Custos de Cuidados de Saúde
10.
J Viral Hepat ; 30(1): 46-55, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36197840

RESUMO

Most high-income countries are not on track to achieve the World Health Organization hepatitis C elimination targets. As elimination programmes assess growing proportions of patients in community-based pathways, rates of treatment uptake may fall. We aimed to identify factors associated with DAA treatment uptake and measure changes in their prevalence over time. We performed a time-to-treatment analysis on 2728 patients approved for hepatitis C Direct-Acting Antiviral treatment in the North Central London region between January 2016 and October 2019. We investigated the association between treatment uptake and factors including assessment/treatment setting (hospital, drug service or prison), patient age, gender, injection drug use, harmful alcohol use, cirrhosis status and previous treatment. The likelihood of treatment uptake was reduced by three independent risk factors. These included assessment setting: prison-based or drug-service pathways (aHR 0.29 or 0.81 vs. hospital outpatient pathway, 95% CI 0.21-0.40 and 0.70-0.94 respectively, p < .001); being UK-born (aHR 0.89 vs. non-UK born, 0.82-0.98, p = .01); and history of harmful alcohol use (aHR 0.84 vs. no history, 0.72-0.99, p = .04). The average number of these risk factors for not starting treatment per patient increased over time (R2  = 0.66 p < .001). Independent of these, there was an additional 5% reduction in rate of treatment initiation in each successive year of the programme (aHR 0.95, 0.91-0.99, p = .02). In conclusion, disengagement from care before treatment uptake was found to be a growing threat to elimination. Despite provision of community-based test-to-cure pathways, there are persistent barriers to treatment uptake and these are increasing over time.


Assuntos
Hepatite C Crônica , Hepatite C , Abuso de Substâncias por Via Intravenosa , Humanos , Antivirais/uso terapêutico , Hepacivirus , Hepatite C/epidemiologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/complicações , Abuso de Substâncias por Via Intravenosa/complicações
11.
Sex Transm Infect ; 99(7): 474-481, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37321843

RESUMO

BACKGROUND: Chemsex (the use of psychoactive drugs in sexual contexts) has been associated with HIV acquisition and other STIs, so there is benefit in identifying those most likely to start chemsex to offer risk reduction interventions such as pre-exposure prophylaxis (PrEP). To date, there have been no data from a longitudinal study analysing factors most associated with starting and stopping chemsex. METHODS: The prospective cohort study, Attitudes to and Understanding Risk of Acquisition of HIV over Time (AURAH2), collected 4 monthly and annual online questionnaire data from men who have sex with men (MSM) from 2015 to 2018. We investigate the association of sociodemographic factors, sexual behaviours and drug use with starting and stopping chemsex among 622 men who completed at least one follow-up questionnaire. Poisson models with generalised estimating equations were used to produce risk ratios (RRs) accounting for multiple starting or stopping episodes from the same individual. Multivariable analysis was adjusted for age group, ethnicity, sexual identity and university education. FINDINGS: In the multivariable analysis, the under 40 age group was significantly more likely to start chemsex by the next assessment (RR 1.79, 95% CI 1.12 to 2.86). Other factors which showed significant association with starting chemsex were unemployment (RR 2.10, 95% CI 1.02 to 4.35), smoking (RR 2.49, 95% CI 1.63 to 3.79), recent condomless sex (CLS), recent STI and postexposure prophylaxis (PEP) use in the past year (RR 2.10, 95% CI 1.33 to 3.30). Age over 40 (RR 0.71, 95% CI 0.51 to 0.99), CLS, and use of PEP (RR 0.64, 95% CI 0.47 to 0.86) and PrEP (RR 0.47, 95% CI 0.29 to 0.78) were associated with lower likelihood of stopping chemsex by the next assessment. INTERPRETATION: Knowledge of these results allows us to identify men most likely to start chemsex, thus providing an opportunity for sexual health services to intervene with a package of risk mitigation measures, especially PrEP use.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Masculino , Humanos , Homossexualidade Masculina , Estudos Prospectivos , Infecções por HIV/prevenção & controle , Estudos Longitudinais , Comportamento Sexual , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Inglaterra/epidemiologia , Inquéritos e Questionários , Profilaxia Pré-Exposição/métodos
12.
Sex Transm Infect ; 99(8): 534-540, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37607814

RESUMO

BACKGROUND: The potential of HIV self-testing (HIVST) to cause harm is a concern hindering widespread implementation. The aim of this paper is to understand the relationship between HIVST and harm in SELPHI (An HIV Self-testing Public Health Intervention), the largest randomised trial of HIVST in a high-income country to date. METHODS: 10 111 cis and trans men who have sex with men (MSM) recruited online (geolocation social/sexual networking apps, social media), aged 16+, reporting previous anal intercourse and resident in England or Wales were first randomised 60/40 to baseline HIVST (baseline testing, BT) or not (no baseline testing, nBT) (randomisation A). BT participants reporting negative baseline test, sexual risk at 3 months and interest in further HIVST were randomised to three-monthly HIVST (repeat testing, RT) or not (no repeat testing, nRT) (randomisation B). All received an exit survey collecting data on harms (to relationships, well-being, false results or being pressured/persuaded to test). Nine participants reporting harm were interviewed in-depth about their experiences in an exploratory substudy; qualitative data were analysed narratively. RESULTS: Baseline: predominantly cis MSM, 90% white, 88% gay, 47% university educated and 7% current/former pre-exposure prophylaxis (PrEP) users. Final survey response rate was: nBT=26% (1056/4062), BT=45% (1674/3741), nRT=41% (471/1147), RT=50% (581/1161).Harms were rare and reported by 4% (n=138/3691) in exit surveys, with an additional two false positive results captured in other study surveys. 1% reported harm to relationships and to well-being in BT, nRT and RT combined. In all arms combined, being pressured or persuaded to test was reported by 1% (n=54/3678) and false positive results in 0.7% (n=34/4665).Qualitative analysis revealed harms arose from the kit itself (technological harms), the intervention (intervention harms) or from the social context of the participant (socially emergent harms). Intervention and socially emergent harms did not reduce HIVST acceptability, whereas technological harms did. DISCUSSION: HIVST harms were rare but strategies to link individuals experiencing harms with psychosocial support should be considered for HIVST scale-up. TRIAL REGISTRATION NUMBER: ISRCTN20312003.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Autoteste , HIV , País de Gales , Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Inglaterra
13.
Langmuir ; 39(44): 15828-15836, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37901970

RESUMO

Nonspherical gold nanoparticles (GNPs) are increasingly used to enhance sensitivity and selectivity in analytical methods such as surface-enhanced Raman spectroscopy (SERS) for detecting trace biomarkers. However, there is limited research on the adsorption properties of aromatic thiols onto gold nanoparticles of different morphologies, where surface curvature varies significantly at the molecular level. In this study, we investigated the adsorption kinetics of 4-mercaptobenzoic acid, an aromatic molecule, on GNPs with different shapes using SERS. Our findings revealed significant differences in the adsorption behavior and binding site preferences of aromatic thiols on GNPs with distinct morphologies. While thiol molecules consider any surface site on nanospheres equally appealing, nanostars exhibit variations in curvature and surface energy, leading to initial binding with further repositioning from the tips of the nanostar after plasmon activation. To address these differences, we proposed a universal method to evaluate the quantity of tightly bound adsorbed molecules on GNPs independently of the particle size, shape, or concentration.

14.
Chirality ; 35(8): 498-504, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36895102

RESUMO

Membranes are important sites of intermolecular interactions in biological systems. However, they present significant analytical challenges as they contain multiple analytes and are dynamic in nature. In this work, we show how a Jasco J-1500 circular dichroism spectropolarimeter can be used with a microvolume Couette flow cell and appropriate cut-off filters to measure excitation fluorescence detected linear dichroism (FDLD) of fluorophores embedded in liposomal membranes. The result is a spectrum that selectively probes the fluorophore(s) and eliminates the scattering that is apparent in the corresponding flow linear dichroism (LD) spectrum. The FDLD spectrum is opposite in sign from the LD spectrum with relative magnitudes modified by the quantum yields of the transitions. FDLD thus enables analyte orientations to be identified in a membrane. Data for a membrane peptide, gramicidin, and two aromatic analytes, anthracene and pyrene, are presented. Issues with the "leakage" of photons by the long pass filters used is also discussed.


Assuntos
Gramicidina , Bicamadas Lipídicas , Bicamadas Lipídicas/química , Estereoisomerismo , Dicroísmo Circular , Gramicidina/química , Peptídeos/química
15.
Ann Intern Med ; 175(9): 1266-1274, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35939810

RESUMO

BACKGROUND: Ensovibep (MP0420) is a designed ankyrin repeat protein, a novel class of engineered proteins, under investigation as a treatment of SARS-CoV-2 infection. OBJECTIVE: To investigate if ensovibep, in addition to remdesivir and other standard care, improves clinical outcomes among patients hospitalized with COVID-19 compared with standard care alone. DESIGN: Double-blind, randomized, placebo-controlled, clinical trial. (ClinicalTrials.gov: NCT04501978). SETTING: Multinational, multicenter trial. PARTICIPANTS: Adults hospitalized with COVID-19. INTERVENTION: Intravenous ensovibep, 600 mg, or placebo. MEASUREMENTS: Ensovibep was assessed for early futility on the basis of pulmonary ordinal scores at day 5. The primary outcome was time to sustained recovery through day 90, defined as 14 consecutive days at home or place of usual residence after hospital discharge. A composite safety outcome that included death, serious adverse events, end-organ disease, and serious infections was assessed through day 90. RESULTS: An independent data and safety monitoring board recommended that enrollment be halted for early futility after 485 patients were randomly assigned and received an infusion of ensovibep (n = 247) or placebo (n = 238). The odds ratio (OR) for a more favorable pulmonary outcome in the ensovibep (vs. placebo) group at day 5 was 0.93 (95% CI, 0.67 to 1.30; P = 0.68; OR > 1 would favor ensovibep). The 90-day cumulative incidence of sustained recovery was 82% for ensovibep and 80% for placebo (subhazard ratio [sHR], 1.06 [CI, 0.88 to 1.28]; sHR > 1 would favor ensovibep). The primary composite safety outcome at day 90 occurred in 78 ensovibep participants (32%) and 70 placebo participants (29%) (HR, 1.07 [CI, 0.77 to 1.47]; HR < 1 would favor ensovibep). LIMITATION: The trial was prematurely stopped because of futility, limiting power for the primary outcome. CONCLUSION: Compared with placebo, ensovibep did not improve clinical outcomes for hospitalized participants with COVID-19 receiving standard care, including remdesivir; no safety concerns were identified. PRIMARY FUNDING SOURCE: National Institutes of Health.


Assuntos
Tratamento Farmacológico da COVID-19 , Adulto , Proteínas de Repetição de Anquirina Projetadas , Método Duplo-Cego , Humanos , Proteínas Recombinantes de Fusão , SARS-CoV-2 , Resultado do Tratamento
16.
J Biol Chem ; 296: 100144, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33273015

RESUMO

Myeloperoxidase (MPO) plays essential roles in neutrophil-mediated immunity via the generation of reactive oxidation products. Complex carbohydrates decorate MPO at discrete sites, but their functional relevance remains elusive. To this end, we have characterised the structure-biosynthesis-activity relationship of neutrophil MPO (nMPO). Mass spectrometry demonstrated that nMPO carries both characteristic under-processed and hyper-truncated glycans. Occlusion of the Asn355/Asn391-glycosylation sites and the Asn323-/Asn483-glycans, located in the MPO dimerisation zone, was found to affect the local glycan processing, thereby providing a molecular basis of the site-specific nMPO glycosylation. Native mass spectrometry, mass photometry and glycopeptide profiling revealed significant molecular complexity of diprotomeric nMPO arising from heterogeneous glycosylation, oxidation, chlorination and polypeptide truncation variants and a previously unreported low-abundance monoprotomer. Longitudinal profiling of maturing, mature, granule-separated and pathogen-stimulated neutrophils demonstrated that nMPO is dynamically expressed during granulopoiesis, unevenly distributed across granules and degranulated upon activation. We also show that proMPO-to-MPO maturation occurs during early/mid-stage granulopoiesis. While similar global MPO glycosylation was observed across conditions, the conserved Asn355-/Asn391-sites displayed elevated glycan hyper-truncation, which correlated with higher enzyme activities of MPO in distinct granule populations. Enzymatic trimming of the Asn355-/Asn391-glycans recapitulated the activity gain and showed that nMPO carrying hyper-truncated glycans at these positions exhibits increased thermal stability, polypeptide accessibility and ceruloplasmin-mediated inhibition potential relative to native nMPO. Finally, molecular modelling revealed that hyper-truncated Asn355-glycans positioned in the MPO-ceruloplasmin interface are critical for uninterrupted inhibition. Here, through an innovative and comprehensive approach, we report novel functional roles of MPO glycans, providing new insight into neutrophil-mediated immunity.


Assuntos
Grânulos Citoplasmáticos/enzimologia , Glicopeptídeos/metabolismo , Neutrófilos/enzimologia , Peroxidase/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Glicopeptídeos/química , Glicosilação , Humanos
17.
Clin Infect Dis ; 75(1): e224-e233, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34549260

RESUMO

BACKGROUND: The public health impact of the coronavirus disease 2019 (COVID-19) pandemic has motivated a rapid search for potential therapeutics, with some key successes. However, the potential impact of different treatments, and consequently research and procurement priorities, have not been clear. METHODS: Using a mathematical model of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission, COVID-19 disease and clinical care, we explore the public-health impact of different potential therapeutics, under a range of scenarios varying healthcare capacity, epidemic trajectories; and drug efficacy in the absence of supportive care. RESULTS: The impact of drugs like dexamethasone (delivered to the most critically-ill in hospital and whose therapeutic benefit is expected to depend on the availability of supportive care such as oxygen and mechanical ventilation) is likely to be limited in settings where healthcare capacity is lowest or where uncontrolled epidemics result in hospitals being overwhelmed. As such, it may avert 22% of deaths in high-income countries but only 8% in low-income countries (assuming R = 1.35). Therapeutics for different patient populations (those not in hospital, early in the course of infection) and types of benefit (reducing disease severity or infectiousness, preventing hospitalization) could have much greater benefits, particularly in resource-poor settings facing large epidemics. CONCLUSIONS: Advances in the treatment of COVID-19 to date have been focused on hospitalized-patients and predicated on an assumption of adequate access to supportive care. Therapeutics delivered earlier in the course of infection that reduce the need for healthcare or reduce infectiousness could have significant impact, and research into their efficacy and means of delivery should be a priority.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Efeitos Psicossociais da Doença , Humanos , Pandemias/prevenção & controle , Preparações Farmacêuticas
18.
HIV Med ; 23(6): 684-692, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34882940

RESUMO

OBJECTIVES: Although direct-acting antivirals (DAAs) can clear HCV in nearly all HIV/HCV-coinfected individuals, high rates of reinfection may hamper efforts to eliminate HCV in this population. We investigated reinfection after sustained virological response (SVR) in HIV/HCV-coinfected individuals in Europe. METHODS: Factors associated with odds of reinfection by 2 years after SVR in EuroSIDA participants with one or more HCV-RNA test and 2 years follow-up were assessed using logistic regression. RESULTS: Overall, 1022 individuals were included. The median age was 50 (interquartile range: 43-54 years), and most were male (78%), injection drug users (52%), and received interferon (IFN)-free DAAs (62%). By 24 months, 75 [7.3%, 95% confidence interval (CI): 5.7-8.9%] individuals were reinfected. Among individuals treated prior to 2014, 16.1% were reinfected compared with 4.2% and 8.3%, respectively, among those treated during or after 2014 with IFN-free and IFN-based therapy. After adjustment, individuals who had started treatment during or after 2014 with IFN-free or IFN-based therapy had significantly lower odds of reinfection (adjusted odds ratio = 0.21, 95% CI: 0.11-0.38; 0.43, 95% CI: 0.22-0.83) compared with those who had received therapy before 2014. There were no significant differences in odds of reinfection according to age, gender, European region, HIV transmission risk group or liver fibrosis. CONCLUSIONS: Among HIV/HCV-coinfected individuals in Europe, 7.3% were reinfected with HCV within 24 months of achieving SVR, with evidence suggesting that this is decreasing over time and with use of newer HCV regimens. Harm reduction to reduce reinfection and surveillance to detect early reinfection with an offer of treatment are essential to eliminate HCV.


Assuntos
Coinfecção , Infecções por HIV , Hepatite C Crônica , Antivirais/uso terapêutico , Coinfecção/complicações , Coinfecção/tratamento farmacológico , Europa (Continente)/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Hepacivirus/genética , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Reinfecção
19.
HIV Med ; 23(3): 209-226, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34634176

RESUMO

OBJECTIVES: There is increasing evidence to suggest that people living with HIV (PLWH) have significant morbidity from alcohol, recreational drug use and cigarette smoking. Our aim was to report associations of these factors with antiretroviral therapy (ART) non-adherence, viral non-suppression and subsequent viral rebound in PLWH. METHODS: The Antiretroviral Sexual Transmission Risk and Attitudes (ASTRA) study recruited PLWH attending eight outpatient clinics in England between February 2011 and December 2012. Data included self-reported excessive drinking (estimated consumption of > 20 units of alcohol/week), alcohol dependency (CAGE score ≥ 2 with current alcohol consumption), recreational drug use (including injection drug use in the past 3 months), and smoking status. Among participants established on ART, cross-sectional associations with ART non-adherence [missing ≥2 consecutive days of ART on ≥2 occasions in the past three months] and viral-non suppression [viral load (VL) > 50 copies/mL] were assessed using logistic regression. In participants from one centre, longitudinal associations with subsequent viral rebound (first VL > 200 copies/mL) in those on ART with VL ≤ 50 copies/mL at baseline were assessed using Cox regression during a 7-year follow-up. RESULTS: Among 3258 PLWH, 2248 (69.0%) were men who have sex with men, 373 (11.4%) were heterosexual men, and 637 (19.6%) were women. A CAGE score ≥ 2 was found in 568 (17.6%) participants, 325 (10.1%) drank > 20 units/week, 1011 (31.5%) currently smoked, 1242 (38.1%) used recreational drugs and 74 (2.3%) reported injection drug use. In each case, prevalence was much more common among men than among women. Among 2459 people on ART who started at least 6 months previously, a CAGE score ≥ 2, drinking > 20 units per week, current smoking, injection and non-injection drug use were all associated with ART non-adherence. After adjusting for demographic and socioeconomic factors, CAGE score ≥ 2 [adjusted odds ratio (aOR) = 1.52, 95% confidence interval (CI): 1.09-2.13], current smoking (aOR = 1.58, 95% CI: 1.10-2.17) and injection drug use (aOR = 2.11, 95% CI: 1.00-4.47) were associated with viral non-suppression. During follow-up of a subset of 592 people virally suppressed at recruitment, a CAGE score ≥ 2 [adjusted hazard ratio (aHR) = 1.66, 95% CI: 1.03-2.74], use of 3 or more non-injection drugs (aHR = 1.82, 95% CI: 1.12-3.57) and injection drug use (aHR = 2.73, 95% CI: 1.08-6.89) were associated with viral rebound. CONCLUSIONS: Screening and treatment for alcohol, cigarette and drug use should be integrated into HIV outpatient clinics, while clinicians should be alert to the potential for poorer virological outcomes.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Minorias Sexuais e de Gênero , Fármacos Anti-HIV/uso terapêutico , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Adesão à Medicação , Uso Recreativo de Drogas , Fumar , Carga Viral
20.
HIV Med ; 23(5): 494-545, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35166004

RESUMO

We present the updated British Association for Sexual Health and HIV (BASHH) guidelines for post-exposure prophylaxis (PEP) to HIV following sexual exposures, occupational exposures and other nonoccupational exposures in the community. This serves as an update to the 2015 BASHH guideline on PEP following sexual exposures and the 2008 Expert Advisory Group on AIDS guidelines on HIV PEP. We aim to provide evidence-based guidance on best clinical practice in the provision, monitoring and support of PEP for the prevention of HIV acquisition following sexual, occupational and other nonoccupational exposures in the community. The guideline covers when to prescribe PEP, what antiretroviral agents to use and how to manage PEP. This includes (i) evidence of PEP efficacy; (ii) evidence relating to individual-level efficacy of antiretroviral therapy to prevent the sexual transmission of HIV; (iii) data on the detectable (transmissible) prevalence of HIV in specific populations; (iv) risk of HIV transmission following different types of sexual and occupational exposure; (v) baseline risk assessment; (vi) drug regimens and dosing schedules; (vii) monitoring PEP; (viii) baseline and follow-up blood-borne virus testing; (ix) the role of PEP within broader HIV prevention strategies, for example, HIV pre-exposure prophylaxis (PrEP). The guideline also covers special scenarios such as PEP in pregnancy, breastfeeding and chronic hepatitis B virus infection, and when PEP should be considered in people using HIV PrEP. The guidelines are aimed at clinical professionals directly involved in PEP provision and other stakeholders in the field. A proforma to assist PEP consultations is included. A public consultation process was undertaken prior to finalizing the recommendations.


Assuntos
Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , Infecções por HIV , Hepatite B Crônica , Profilaxia Pré-Exposição , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Profilaxia Pós-Exposição , Gravidez , Reino Unido
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