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Introduction: The British Association of Perinatal Medicine (BAPM) released their revised framework for extremely preterm infant management in 2019. This revised framework promotes consideration of perinatal optimisation and survival-focused care from 22 weeks gestation onwards. This was a departure from the previous BAPM framework which recommended comfort care as the only recommended management for infants <23 + 0 weeks. Methods: Our study evaluates the clinical impact that this updated framework has had across the Northwest of England. We utilised anonymised network data from periviable infants delivered across the region to examine changes in perinatal optimisation practices and survival outcomes following the release of the latest BAPM framework. Results: Our data show that after the introduction of the updated framework there has been an increase in perinatal optimisation practices for periviable infants and an 80% increase in the number of infants born at 22 weeks receiving survival-focused care and admission to a neonatal unit. Discussion: There remain significant discrepancies in optimisation practices by gestational age, which may be contributing to the static survival rates that were observed in the lowest gestational ages.
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BACKGROUND: Medicalised Conception (MAC) assists many couples to achieve pregnancy worldwide. As the impact of MAC has been linked to increased pregnancy-specific anxiety and parenting difficulties, this review aimed to explore parental experiences of pregnancy and early parenting following MAC, identifying parents' psychological, social and health needs. METHOD: Five databases were searched systematically from inception to March 2023. Identified articles were screened for eligibility against the inclusion criteria and the results were analysed using thematic synthesis. The Critical Appraisal Skills checklist was employed to appraise methodological quality. RESULTS: Twenty qualitative studies, drawing on a total of 19 participant samples, were included in this review, most with samples with history of subfertility. The findings were synthesised into three main themes (consisting of seven subthemes): 1) The vulnerable parent: fear, doubt, uncertainty, 2) the stark realisation of the parental dream, 3) psychosocial needs and support. Parents lacked a sense of safety during pregnancy and reported acting protectively both antenatally and postnatally. Furthermore, their identity transition was complex and non-linear, influenced by sociocultural context. CONCLUSIONS: Considerable unmet psychosocial needs were identified including the potential for anxiety in pregnancy, the possibility of feeling excluded and marginalised, and a reluctance to share distress and experiences with healthcare professionals. These findings suggest a need for consistent, holistic care, integrating psychological services.
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Poder Familiar , Pais , Técnicas de Reprodução Assistida , Feminino , Humanos , Gravidez , Emoções , Pessoal de Saúde , Poder Familiar/psicologia , Pais/psicologia , Pesquisa QualitativaRESUMO
The consequences of Serious Mental Illness (SMI) on parent and child outcomes can be profound. Supporting parents to manage their caregiving roles alongside parental SMI successfully has been recognised as a public health priority. To meet this priority and develop effective and acceptable interventions, it is imperative that parents' experiences and support needs are understood. This systematic review aimed to synthesise qualitative research that explored parents' experiences and perceptions of the impact of SMI on their parenting and their corresponding support needs. The Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines were followed. Five databases were searched for terms associated with SMI, parenting, and qualitative research. Twenty-nine studies involving 562 parents who experienced SMI met inclusion criteria, and the methodological quality of included studies was appraised using the Critical Appraisal Skills Programme. After findings were synthesised using thematic synthesis, six themes were identified: (1) The constrained parent, (2) parenting difficulties, (3) the strained child, (4) inescapable threat, (5) combatting threat, and (6) wrap-around support needs. Novel insights into the centrality of SMI-related parenting difficulties and threat perceptions across parent, family, healthcare, and wider social systems on strained parent-child and distanced parent-support relationships were highlighted. Systemic practice change initiatives via compassionate and inclusive system-wide support were recommended.
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Transtornos Mentais , Poder Familiar , Humanos , Pais , Pesquisa Qualitativa , Transtornos Mentais/terapiaRESUMO
BACKGROUND: Over the last 20 years, compassion focused therapy (CFT) has gained popularity as an emerging 'third wave' intervention. Although previous reviews indicated its potential benefits, a systematic review and meta-analysis of CFT in those with mental health difficulties has yet to be conducted. METHODS: A systematic search of five databases was undertaken, focusing on randomised controlled trials and randomised pilot/feasibility studies of CFT only. No language restrictions were implemented. A narrative synthesis was conducted. Random effects meta-analyses were measured on levels of self-compassion, self-criticism/self-reassurance, fears of compassion and clinical symptomology. RESULTS: Fifteen studies from 2013 to 2022 were included. Findings suggested that CFT was effective in improving compassion-based outcomes and clinical symptomology from baseline to post-intervention and compared to waitlist control. A range of small to large effect sizes were reported for improvements in self-compassion (0.19-0.90), self-criticism (0.15-0.72), self-reassurance (0.43-0.81), fear of self-compassion (0.18), depression (0.24-0.25) and eating disorders (0.18-0.79). Meta-analyses favoured CFT in improving levels of self-compassion and self-reassurance than control groups. LIMITATIONS: The methodological quality of many of the included studies (7/15) was rated as 'unclear' due to a lack of information. There was a distinct gender gap, with 74.88% identifying as female participants. CONCLUSIONS: This review was the first to examine the effectiveness of CFT in clinical populations. The results indicate that CFT has promising clinical implications, suggesting that the intervention increases compassion-based outcomes and reduces clinical symptomology in those with mental health difficulties. However, future research is required into the long-term effects of CFT.
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Transtornos da Alimentação e da Ingestão de Alimentos , Psicoterapia de Grupo , Humanos , Feminino , Empatia , Psicoterapia de Grupo/métodos , Medo/psicologia , Autoavaliação (Psicologia)RESUMO
BACKGROUND: Lysosomal acid lipase deficiency (LALD) is an ultra-rare, inherited metabolic disease within the category of lysosomal storage disorders, affecting an infant's ability to metabolise cholesterol. Developments in treatment, including Enzyme Replacement Therapy, have proven successful, with some children living for a number of years with treatment, although the future still remains unknown. The aim of this study was to explore the lived experiences of parents of children with LALD. MAIN TEXT: Participants were recruited from across the United Kingdom between 2020 and 2021. Eight parents (five mothers and three fathers) whose child had a confirmed diagnosis of LALD were interviewed. Data collected from the semi-structured interviews were audio-record, transcribed and analysed using Interpretative Phenomenological Analysis (IPA). Three superordinate and nine subordinate themes emerged from the data: (1) Uncertainty-a double-edged sword (plunged into an uncertain world, living life with worry and walking the tightrope of stability), (2) Powerless against a shared battle with LALD (a helpless parent, a joint battle, protection against distress and a vulnerable parent needing help) and 3) Accepting a life with LALD (coming to terms with a diagnosis of LALD and a hidden condition). CONCLUSIONS: The findings of this study highlight that the diagnosis of LALD proves to be a very challenging and emotionally distressing time in parents' lives, with increased uncertainty about what the future will hold for their child. This study signified the importance of healthcare pathways and service provisions to support parents and their children throughout diagnosis and beyond.
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Doença de Wolman , Criança , Terapia de Reposição de Enzimas , Feminino , Humanos , Lactente , Mães , Pais/psicologia , Pesquisa Qualitativa , Doença de Wolman/diagnóstico , Doença de WolmanRESUMO
The possibility that Arctic sea ice loss weakens mid-latitude westerlies, promoting more severe cold winters, has sparked more than a decade of scientific debate, with apparent support from observations but inconclusive modelling evidence. Here we show that sixteen models contributing to the Polar Amplification Model Intercomparison Project simulate a weakening of mid-latitude westerlies in response to projected Arctic sea ice loss. We develop an emergent constraint based on eddy feedback, which is 1.2 to 3 times too weak in the models, suggesting that the real-world weakening lies towards the higher end of the model simulations. Still, the modelled response to Arctic sea ice loss is weak: the North Atlantic Oscillation response is similar in magnitude and offsets the projected response to increased greenhouse gases, but would only account for around 10% of variations in individual years. We further find that relationships between Arctic sea ice and atmospheric circulation have weakened recently in observations and are no longer inconsistent with those in models.
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The emergence of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) herald a new phase of the pandemic. This study used state-of-the-art phylodynamic methods to ascertain that the rapid rise of B.1.1.7 "Variant of Concern" most likely occurred by global dispersal rather than convergent evolution from multiple sources.
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COVID-19 , SARS-CoV-2 , Humanos , FilogeniaRESUMO
A bis-ethene chromium(I) species, which is the postulated key intermediate in the widely accepted metallacyclic mechanism for ethene oligomerization, is experimentally observed. This catalytic transformation is an important commercial route to linear α-olefins (primarily, 1-hexene and 1-octene), which act as comonomers for the production of polyethene. Here, electron paramagnetic resonance studies of a catalytic system based on [Cr(CO)4(PNP)][Al(OC(CF3)3)4] [PNP = Ph2PN(iPr)PPh2] activated with Et6Al2 provide the first unequivocal evidence for a chromium(I) bis-ethene complex. The concentration of this species is enhanced under ethene and isotope labeling studies that confirm its composition as containing [Cr(C2H4)2(CO)2(PNP)]+ These observations open a new route to mechanistic studies of selective ethene oligomerization.
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BACKGROUND: Identifying the extent of environmental contamination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for infection control and prevention. The extent of environmental contamination has not been fully investigated in the context of severe coronavirus disease (COVID-19) patients. AIM: To investigate environmental SARS-CoV-2 contamination in the isolation rooms of severe COVID-19 patients requiring mechanical ventilation or high-flow oxygen therapy. METHODS: Environmental swab samples and air samples were collected from the isolation rooms of three COVID-19 patients with severe pneumonia. Patients 1 and 2 received mechanical ventilation with a closed suction system, while patient 3 received high-flow oxygen therapy and non-invasive ventilation. Real-time reverse transcription-polymerase chain reaction (rRT-PCR) was used to detect SARS-CoV-2; viral cultures were performed for samples not negative on rRT-PCR. FINDINGS: Of the 48 swab samples collected in the rooms of patients 1 and 2, only samples from the outside surfaces of the endotracheal tubes tested positive for SARS-CoV-2 by rRT-PCR. However, in patient 3's room, 13 of the 28 environmental samples (fomites, fixed structures, and ventilation exit on the ceiling) showed positive results. Air samples were negative for SARS-CoV-2. Viable viruses were identified on the surface of the endotracheal tube of patient 1 and seven sites in patient 3's room. CONCLUSION: Environmental contamination of SARS-CoV-2 may be a route of viral transmission. However, it might be minimized when patients receive mechanical ventilation with a closed suction system. These findings can provide evidence for guidelines for the safe use of personal protective equipment.
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Infecções por Coronavirus/terapia , Descontaminação/normas , Poluição Ambiental/análise , Oxigenoterapia Hiperbárica/normas , Quartos de Pacientes/normas , Pneumonia Viral/terapia , Pneumonia/terapia , Guias de Prática Clínica como Assunto , Respiração Artificial/normas , Microbiologia do Ar , COVID-19 , Humanos , PandemiasRESUMO
OBJECTIVES: People living with HIV (PWH) are at elevated risk of cardiac disease compared to the general population. Methamphetamine use has been associated with structural heart disease and increased mortality from cardiovascular disease but has not been explored as a cause of cardiac disease among PWH. We sought to evaluate the association of methamphetamine use and cardiac disease among PWH. METHODS: We performed a case-control study of participant data in the HIV Neurobehavioral Research Program. Cases were defined as PWH with a history of myocardial infarction or a history of heart failure (systolic or diastolic). Covariates, including methamphetamine abuse/dependence, were assessed using multiple logistic regression. RESULTS: Among 3747 PWH, there was a history of myocardial infarction in 115 subjects (3.1%), and a history of heart failure in 41 (1.1%). Current or prior methamphetamine abuse/dependence was reported in 1036 (27.9%) and was not associated with myocardial infarction (P = 0.27) or heart failure (P = 0.84). In addition to traditional risk factors, variables associated with myocardial infarction included the presence of HIV infection (P = 0.01) and duration of HIV infection (P = 0.05). Variables associated with heart failure among PWH included older age, hypertension and myocardial infarction. CONCLUSIONS: No association between methamphetamine abuse/dependence and a diagnosis of myocardial infarction or heart failure was found among PWH. Significant covariates for myocardial infarction and heart failure included traditional risk factors, the presence of HIV infection and the duration of HIV infection, emphasizing the need for optimal traditional cardiovascular risk factor management among PWH.
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Transtornos Relacionados ao Uso de Anfetaminas/epidemiologia , Infecções por HIV/epidemiologia , Insuficiência Cardíaca/epidemiologia , Hipertensão/epidemiologia , Infarto do Miocárdio/epidemiologia , Adulto , Fatores Etários , Transtornos Relacionados ao Uso de Anfetaminas/complicações , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/induzido quimicamente , Humanos , Modelos Logísticos , Masculino , Metanfetamina/efeitos adversos , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Fatores de RiscoRESUMO
Quantifying signals and uncertainties in climate models is essential for the detection, attribution, prediction and projection of climate change1-3. Although inter-model agreement is high for large-scale temperature signals, dynamical changes in atmospheric circulation are very uncertain4. This leads to low confidence in regional projections, especially for precipitation, over the coming decades5,6. The chaotic nature of the climate system7-9 may also mean that signal uncertainties are largely irreducible. However, climate projections are difficult to verify until further observations become available. Here we assess retrospective climate model predictions of the past six decades and show that decadal variations in North Atlantic winter climate are highly predictable, despite a lack of agreement between individual model simulations and the poor predictive ability of raw model outputs. Crucially, current models underestimate the predictable signal (the predictable fraction of the total variability) of the North Atlantic Oscillation (the leading mode of variability in North Atlantic atmospheric circulation) by an order of magnitude. Consequently, compared to perfect models, 100 times as many ensemble members are needed in current models to extract this signal, and its effects on the climate are underestimated relative to other factors. To address these limitations, we implement a two-stage post-processing technique. We first adjust the variance of the ensemble-mean North Atlantic Oscillation forecast to match the observed variance of the predictable signal. We then select and use only the ensemble members with a North Atlantic Oscillation sufficiently close to the variance-adjusted ensemble-mean forecast North Atlantic Oscillation. This approach greatly improves decadal predictions of winter climate for Europe and eastern North America. Predictions of Atlantic multidecadal variability are also improved, suggesting that the North Atlantic Oscillation is not driven solely by Atlantic multidecadal variability. Our results highlight the need to understand why the signal-to-noise ratio is too small in current climate models10, and the extent to which correcting this model error would reduce uncertainties in regional climate change projections on timescales beyond a decade.
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To assess the potential for decreased condom use as pre-exposure prophylaxis (PrEP) is scaled-up in Latin America, we examined HIV prevention method preferences (neither PrEP nor condoms, condoms only, PrEP only, or PrEP with condoms) within 1302 sexual partnerships reported by 397 HIV-negative men who have sex with men (MSM) and transgender women (TW) in Tijuana, Mexico. Using PrEP with condoms (56%) was preferred to using condoms only (24%), using PrEP only (17%), and using neither PrEP nor condoms (3%). Compared to using condoms only, using PrEP only was preferred within primary (adjusted odds ratio [AOR] = 4.13, 95% confidence interval [CI] 1.92, 8.90) and condomless sex practicing (AOR = 6.97, 95% CI 3.92, 12.40) partnerships, suggesting PrEP use may not displace condom use among MSM and TW in Tijuana and other similar settings.
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Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/psicologia , Preferência do Paciente , Profilaxia Pré-Exposição/métodos , Pessoas Transgênero/psicologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Preservativos , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , México , Pessoa de Meia-Idade , Sexo Seguro , Comportamento Sexual , Parceiros Sexuais , Pessoas Transgênero/estatística & dados numéricosRESUMO
With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.
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Alternative postharvest sanitizers to chlorine are of increasing interest for many organic growers and consumers. An emulsion of clove bud oil (CBO; 0.2 and 0.5%) or thyme oil (0.2 and 0.5%) was evaluated as a sanitizer for produce washing against a five-serovar cocktail of Salmonella on snacking peppers and compared for antimicrobial efficacy with sodium hypochlorite (200 ppm). To further evaluate these compounds, the sanitation efficacy of an emulsion was examined after the addition of 1% organic load (OL). Emulsion treatments at 0.2 and 0.5% thyme oil and 0.5% CBO were the least effected by OL and effectively reduced cross-contamination of Salmonella on clean peppers, in many cases to below the limit of detection (1 CFU/10 g; P < 0.05). Chlorine and 0.2% CBO were rendered ineffective by the addition of OL in preventing cross-contamination and performed similarly to the water control. For surface-inoculated peppers, none of the evaluated treatments performed better than a water-only wash. The antimicrobial efficacy of the essential oil emulsions in the presence of OL indicates these emulsions may be suitable replacements for chlorine in postharvest produce wash systems.
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Capsicum/microbiologia , Desinfetantes , Contaminação de Alimentos/prevenção & controle , Óleos Voláteis , Salmonella/efeitos dos fármacos , Cloro , Contagem de Colônia Microbiana , Desinfetantes/farmacologia , Emulsões , Manipulação de Alimentos , Microbiologia de Alimentos , Humanos , Óleos Voláteis/farmacologia , Salmonella/crescimento & desenvolvimentoRESUMO
The objective was to examine shelf stability, cooked product yield, and sensory characteristics of beef patties that had no binder (Control), incorporated soy flour (Textured Vegetable Protein; TVP) or one of three dry potato extracts: X-TRATOS™ (potato extract), X-TRATOS™ O (potato extract with mustard), or X-TRATOS™ W (potato extract with sodium acid pyrophosphate). In retail display patties, all binders decreased discoloration and lipid oxidation compared to Control, and X-TRATOS™ O was superior (Pâ¯<â¯0.05) to all other treatments. Cooking yield was higher (Pâ¯<â¯0.05) in patties containing potato extracts compared with patties containing TVP, which had higher yield than Control patties. Beef patties with potato extracts were juicier (Pâ¯<â¯0.05) than Control and TVP patties and had higher (Pâ¯<â¯0.05) overall acceptability than Control patties. We conclude that potato extracts are effective binders for use in fresh or precooked beef patties because they improve retail shelf life, cooked product yield, and sensory characteristics.
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Produtos da Carne/análise , Extratos Vegetais/química , Solanum tuberosum , Animais , Bovinos , Cor , Comportamento do Consumidor , Culinária , Difosfatos/química , Armazenamento de Alimentos , Humanos , Peroxidação de Lipídeos , Mostardeira , Glycine max , Água/químicaRESUMO
Breastfeeding can play a key role in the reduction of obesity, but initiation and maintenance rates in women with a body mass index (BMI) of ≥30 kg m-2 are low. Psychological factors influence breastfeeding behaviours in the general population, but their role is not yet understood in women with a BMI ≥30 kg m-2 . Therefore, this review aimed to systematically search and synthesize the literature, which has investigated the association between any psychological factor and breastfeeding behaviour in women with a BMI ≥30 kg m-2 . The search identified 20 eligible papers, reporting 16 psychological factors. Five psychological factors were associated with breastfeeding behaviours: intentions to breastfeed, belief in breast milk's nutritional adequacy and sufficiency, belief about other's infant feeding preferences, body image and social knowledge. It is therefore recommended that current care should encourage women to plan to breastfeed, provide corrective information for particular beliefs and address their body image and social knowledge. Recommendations for future research include further exploration of several psychological factors (i.e. expecting that breastfeeding will enhance weight loss, depression, anxiety and stress) and evidence and theory-based intervention development.
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Índice de Massa Corporal , Aleitamento Materno/psicologia , Comportamento Materno/psicologia , Mães/psicologia , Obesidade/psicologia , Imagem Corporal/psicologia , Aleitamento Materno/estatística & dados numéricos , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Intenção , Redução de PesoRESUMO
The study aimed to determine the prevalence of occult hepatitis B virus infection among HIV-infected persons and to evaluate the use of a pooling strategy to detect occult HBV infection in the setting of HIV infection. Five hundred and two HIV-positive individuals were tested for HBV, occult HBV and hepatitis C and D with serologic and nucleic acid testing (NAT). We also evaluated a pooled NAT strategy for screening occult HBV infection among the HIV-positive individuals. The prevalence of HBV infection among HIV-positive individuals was 32 (6.4%), and occult HBV prevalence was 10%. The pooling HBV NAT had a sensitivity of 66.7% and specificity of 100%, compared to HBV DNA NAT of individual samples. In conclusion, this study found a high prevalence of occult HBV infection among our HIV-infected population. We also demonstrated that pooled HBV NAT is highly specific, moderately sensitive and cost-effective. As conventional HBV viral load assays are expensive in resource-limited settings such as India, pooled HBV DNA NAT might be a good way for detecting occult HBV infection and will reduce HBV-associated complications.
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DNA Viral/isolamento & purificação , Infecções por HIV/complicações , Vírus da Hepatite B/isolamento & purificação , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Técnicas de Diagnóstico Molecular/métodos , Manejo de Espécimes/métodos , Adulto , Feminino , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite D/diagnóstico , Hepatite D/epidemiologia , Humanos , Índia/epidemiologia , Masculino , Sensibilidade e EspecificidadeRESUMO
Defined arrangements of individual molecules are covalenty connected ("printed") onto SAM-functionalised gold substrates with nanometer resolution. Substrates were initially pre-functionlised by coating with 3,3'-dithiodipropionic acid (DTPA) to form a self-assembled monolayer (SAM), which was characterised by atomic force microscopy (AFM), contact angle goniometry, cyclic voltammetry and surface plasmon resonance (SPR) spectroscopy. Pre-defined "ink" patterns displayed on DNA origami-based single-use carriers ("stamp") were covalently conjugated to the SAM using 1-ethyl-3-(3-dimethylamino-propyl)carbodiimide (EDC) and N-hydroxy-succinimide (NHS). These anchor points were used to create nanometer-precise single-molecule arrays, here with complementary DNA and streptavidin. Sequential steps of the printing process were evaluated by AFM and SPR spectroscopy. It was shown that 30% of the detected arrangements closely match the expected length distribution of designed patterns, whereas another 40% exhibit error within the range of only 1 streptavidin molecule. SPR results indicate that imposing a defined separation between molecular anchor points within the pattern through this printing process enhances the efficiency for association of specific binding partners for systems with high sterical hindrance. This study expands upon earlier findings where geometrical information was conserved by the application of DNA nanostructures, by establishing a generalisable strategy which is universally applicable to nearly any type of prefunctionalised substrate such as metals, plastics, silicates, ITO or 2D materials.
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In obesity fasting levels of both glucagon and insulin are elevated. In these subjects fasting levels of the free fatty acid palmitate are raised. We have demonstrated that palmitate enhances glucose-stimulated insulin secretion from isolated human islets via free fatty acid receptor 1 (FFAR1/GPR40). Since FFAR1 is also present on glucagon-secreting alpha-cells, we hypothesized that palmitate simultaneously stimulates secretion of glucagon and insulin at fasting glucose concentrations. In addition, we hypothesized that concomitant hypersecretion of glucagon and insulin was also contributed by reduced somatostatin secretion. We found basal glucagon, insulin and somatostatin secretion and respiration from human islets, to be enhanced during palmitate treatment at normoglycemia. Secretion of all hormones and mitochondrial respiration were lowered when FFAR1 or fatty acid ß-oxidation was inhibited. The findings were confirmed in the human beta-cell line EndoC-ßH1. We conclude that fatty acids enhance both glucagon and insulin secretion at fasting glucose concentrations and that FFAR1 and enhanced mitochondrial metabolism but not lowered somatostatin secretion are crucial in this effect. The ability of chronically elevated palmitate levels to simultaneously increase basal secretion of glucagon and insulin positions elevated levels of fatty acids as potential triggering factors for the development of obesity and impaired glucose control.