RESUMO
BACKGROUND & AIMS: Infections are life-threatening to patients with acute decompensation and acute-on-chronic liver failure (AD/ACLF). Patients with AD/ACLF have prostaglandin E2-mediated immune suppression, which can be reversed by administration of albumin; infusion of 20% human albumin solution (HAS) might improve outcomes of infections. We performed a feasibility study to determine optimal trial design, assess safety, and validate laboratory assessments of immune function to inform design of a phase 3 trial. METHODS: We performed a prospective multicenter, single-arm, open-label trial of 79 patients with AD/ACLF and levels of albumin lower than 30 g/L, seen at 10 hospitals in the United Kingdom from May through December 2015. Patients were given daily infusions of 20% HAS, based on serum levels, for 14 days or until discharge from the hospital. Rates of infection, organ dysfunction, and in-hospital mortality were recorded. The primary end point was daily serum albumin level during the treatment period. Success would be demonstrated if 60% achieved and maintained serum albumin levels at or above 30 g/L on at least one third of days with recorded levels. RESULTS: The patients' mean model for end-stage disease score was 20.9 ± 6.6. The primary end point (albumin ≥30 g/L on at least one third of days recorded) was achieved by 68 of the 79 patients; 75% of administrations were in accordance with suggested dosing regimen. Mean treatment duration was 10.3 days (104 ± 678 mL administered). There were 8 deaths and 13 serious adverse events, considered by the independent data-monitoring committee to be consistent with those expected. Twelve of 13 patients that developed either respiratory or cardiovascular dysfunction (based on ward-based clinical definitions) as their only organ dysfunction were alive at 30 days compared with 1 of 3 that developed renal dysfunction. Only 1 case of brain dysfunction was recorded. CONCLUSIONS: In a feasibility trial, we found that administration of HAS increased serum levels of albumin in patients with AD/ACLF. The dosing regimen was acceptable at multiple sites and deemed safe by an independent data-monitoring committee. We also developed a robust system to record infections. The poor prognosis for patients with renal dysfunction was confirmed. However, patients with cardiovascular or respiratory dysfunction had good outcomes, which is counterintuitive. Severe encephalopathy appeared substantially under-reported, indicating that ward-based assessment of these parameters cannot be recorded with sufficient accuracy for use as a primary outcome in phase 3 trials. Trial registration no: EudraCT 2014-002300-24 and ISRCTN14174793.
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Doença Hepática Terminal/terapia , Fatores Imunológicos/administração & dosagem , Infecções Oportunistas/prevenção & controle , Albumina Sérica Humana/administração & dosagem , Soro/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos Fase III como Assunto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Doença Hepática Terminal/complicações , Feminino , Humanos , Fatores Imunológicos/farmacocinética , Fatores Imunológicos/farmacologia , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Albumina Sérica Humana/farmacocinética , Albumina Sérica Humana/farmacologia , Reino Unido , Adulto JovemRESUMO
BACKGROUND: Neuro-inflammation has long been implicated as a contributor to the progression of Alzheimer's disease in both humans and animal models. Type-1 interferons (IFNs) are pleiotropic cytokines critical in mediating the innate immune pro-inflammatory response. The production of type-1 IFNs following pathogen detection is, in part, through the activation of the toll-like receptors (TLRs) and subsequent signalling through myeloid differentiation factor-88 (Myd88) and interferon regulatory factors (IRFs). We have previously identified that neuronal type-1 IFN signalling, through the type-1 interferon alpha receptor-1 (IFNAR1), is detrimental in models of AD. Using an in vitro approach, this study investigated the TLR network as a potential production pathway for neuronal type-1 IFNs in response to Aß. METHODS: Wildtype and Myd88(-/-) primary cultured cortical and hippocampal neurons were treated with 2.5 µM Aß1-42 for 24 to 72 h or 1 to 10 µM Aß1-42 for 72 h. Human BE(2)M17 neuroblastoma cells stably expressing an IRF7 small hairpin RNA (shRNA) or negative control shRNA construct were subjected to 7.5 µM Aß1-42/Aß42-1 for 24 to 96 h, 2.5 to 15 µM Aß1-42 for 96 h or 100 ng/ml LPS for 0.5 to 24 h. Q-PCR was used to analyse IFNα, IFNß, IL-1ß, IL-6 and TNFα mRNA transcript levels. Phosphorylation of STAT-3 was detected by Western blot analysis, and cell viability was assessed by MTS assay. RESULTS: Reduced IFNα, IFNß, IL-1ß, IL-6 and TNFα expression was detected in Aß1-42-treated Myd88(-/-) neurons compared to wildtype cells. This correlated with reduced phosphorylation of STAT-3, a downstream type-1 IFN signalling mediator. Significantly, Myd88(-/-) neuronal cultures were protected against Aß1-42-induced neurotoxicity compared to wildtype as determined by MTS assay. Knockdown of IRF7 in M17 cells was sufficient in blocking IFNα, IFNß and p-STAT-3 induction to both Aß1-42 and the TLR4 agonist LPS. M17 IRF7 KD cells were also protected against Aß1-42-induced cytotoxicity. CONCLUSIONS: This study confirms that the neuronal type-1 IFN response to soluble amyloid is mediated primarily through TLRs. This production is dependent upon Myd88 and IRF7 signalling. This study suggests that targeting this pathway to modulate neuronal type-1 IFN levels may be beneficial in controlling Aß-induced neurotoxicity.
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Peptídeos beta-Amiloides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Fator Regulador 7 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fragmentos de Peptídeos/farmacologia , Análise de Variância , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Regulação da Expressão Gênica/genética , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Transgênicos , Fator 88 de Diferenciação Mieloide/genética , Neuroblastoma/patologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , TransfecçãoRESUMO
Sepsis with multi organ dysfunction syndrome (MODS) is the most common cause of death in patients in noncoronary intensive care units. Currently, there are no specific treatments that reduce mortality in patients with sepsis and MODS. We report three patients who received therapeutic plasma exchange (TPE) for sepsis with MODS who completely recovered. The first patient, a 3-year-old male presented with Methicillin-resistant Staphylococcus aureus-associated respiratory, renal, coagulation, hepatic, and neurologic dysfunction. After 5 TPEs, the patient fully recovered. The second patient was a 36-year-old pregnant female who developed MODS at 22 weeks of gestation. She had developed respiratory, hepatic, renal, cardiovascular, neurologic, and coagulation dysfunction following pneumonia and concurrent urinary tract infection resulting in an intrauterine fetal demise. After 8 TPEs, the patient was discharged home with only mild residual hepatic dysfunction. The third patient, a 50-year-old female with a history of seizure disorder, was found unresponsive in over 100°F heat and diagnosed with Staphylococcus aureus-associated MODS. Her respiratory, coagulation, neurologic, renal, and hepatic systems were affected. The patient underwent 6 TPEs after which she had marked improvement. In conclusion, TPE may be an effective adjunct therapy in MODS by possibly removing toxic mediators and replacing deficient factors using donor plasma.
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Insuficiência de Múltiplos Órgãos/terapia , Troca Plasmática , Sepse/terapia , Adulto , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/imunologia , Sepse/imunologiaRESUMO
OBJECTIVE: To assess whether an easy-to-use multifaceted intervention for children presenting to primary care with respiratory tract infections would reduce antibiotic dispensing, without increasing hospital admissions for respiratory tract infection. DESIGN: Two arm randomised controlled trial clustered by general practice, using routine outcome data, with qualitative and economic evaluations. SETTING: English primary care practices using the EMIS electronic medical record system. PARTICIPANTS: Children aged 0-9 years presenting with respiratory tract infection at 294 general practices, before and during the covid-19 pandemic. INTERVENTION: Elicitation of parental concerns during consultation; a clinician focused prognostic algorithm to identify children at very low, normal, or elevated 30 day risk of hospital admission accompanied by antibiotic prescribing guidance; and a leaflet for carers including safety netting advice. MAIN OUTCOME MEASURES: Rate of dispensed amoxicillin and macrolide antibiotics (superiority comparison) and hospital admissions for respiratory tract infection (non-inferiority comparison) for children aged 0-9 years over 12 months (same age practice list size as denominator). RESULTS: Of 310 practices needed, 294 (95%) were randomised (144 intervention and 150 controls) representing 5% of all registered 0-9 year olds in England. Of these, 12 (4%) subsequently withdrew (six owing to the pandemic). Median intervention use per practice was 70 (by a median of 9 clinicians). No evidence was found that antibiotic dispensing differed between intervention practices (155 (95% confidence interval 138 to 174) items/year/1000 children) and control practices (157 (140 to 176) items/year/1000 children) (rate ratio 1.011, 95% confidence interval 0.992 to 1.029; P=0.25). Pre-specified subgroup analyses suggested reduced dispensing in intervention practices with fewer prescribing nurses, in single site (compared with multisite) practices, and in practices located in areas of lower socioeconomic deprivation, which may warrant future investigation. Pre-specified sensitivity analysis suggested reduced dispensing among older children in the intervention arm (P=0.03). A post hoc sensitivity analysis suggested less dispensing in intervention practices before the pandemic (rate ratio 0.967, 0.946 to 0.989; P=0.003). The rate of hospital admission for respiratory tract infections in the intervention practices (13 (95% confidence interval 10 to 18) admissions/1000 children) was non-inferior compared with control practices (15 (12 to 20) admissions/1000 children) (rate ratio 0.952, 0.905 to 1.003). CONCLUSIONS: This multifaceted antibiotic stewardship intervention for children with respiratory tract infections did not reduce overall antibiotic dispensing or increase respiratory tract infection related hospital admissions. Evidence suggested that in some subgroups and situations (for example, under non-pandemic conditions) the intervention slightly reduced prescribing rates but not in a clinically relevant way. TRIAL REGISTRATION: ISRCTN11405239ISRCTN registry ISRCTN11405239.
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COVID-19 , Infecções Respiratórias , Humanos , Criança , Adolescente , Antibacterianos/uso terapêutico , Tosse/tratamento farmacológico , Pandemias , Infecções Respiratórias/tratamento farmacológico , Atenção Primária à SaúdeRESUMO
Background: Clinical uncertainty in primary care regarding the prognosis of children with respiratory tract infections contributes to the unnecessary use of antibiotics. Improved identification of children at low risk of future hospitalisation might reduce clinical uncertainty. A National Institute for Health and Care Research-funded 5-year programme (RP-PG-0608-10018) was used to develop and feasibility test an intervention. Objectives: The aim of the children with acute cough randomised controlled trial was to reduce antibiotic prescribing among children presenting with acute cough and respiratory tract infection without increasing hospital admission. Design: An efficient, pragmatic open-label, two-arm trial (with embedded qualitative and health economic analyses) using practice-level randomisation using routinely collected data as the primary outcome. Setting: General practitioner practices in England. Participants: General practitioner practices using the Egton Medical Information Systems® patient-record system for children aged 0-9 years presenting with a cough or upper respiratory tract infection. Recruited by Clinical Research Networks and Clinical Commissioning Groups. Intervention: Comprised: (1) elicitation of parental concerns during consultation; (2) a clinician-focused prognostic algorithm to identify children with acute cough and respiratory tract infection at low, average or elevated risk of hospitalisation in the next 30 days accompanied by prescribing guidance, (3) provision of a printout for carers including safety-netting advice. Main outcome measures: Co-primaries using the practice list-size for children aged 0-9 years as the denominator: rate of dispensed amoxicillin and macrolide items at each practice (superiority comparison) from NHS Business Services Authority ePACT2 and rate of hospital admission for respiratory tract infection (non-inferiority comparison) from Clinical Commissioning Groups, both routinely collected over 12 months. Results: Of the 310 practices required, 294 (95%) were recruited (144 intervention and 150 controls) with 336,496 registered 0-9-year-olds (5% of all 0-9-year-old children in England) from 47 Clinical Commissioning Groups. Included practices were slightly larger than those not included, had slightly lower baseline dispensing rates and were located in more deprived areas (reflecting the distribution for practice postcodes nationally). Twelve practices (4%) subsequently withdrew (six related to the pandemic). The median number of times the intervention was used was 70 per practice (by a median of 9 clinicians) over 12 months. There was no evidence that the antibiotic dispensing rate in the intervention practices [0.155 (95% confidence interval 0.135 to 0.179)] differed to controls [0.154 (95% confidence interval 0.130 to 0.182), relative risk= 1.011 (95% confidence interval 0.992 to 1.029); p = 0.253]. There was, overall, a reduction in dispensing levels and intervention usage during the pandemic. The rate of hospitalisation for respiratory tract infection in the intervention practices [0.019 (95% confidence interval 0.014 to 0.026)] compared to the controls [0.021 (95% confidence interval 0.014 to 0.029)] was non-inferior [relative risk = 0.952 (95% confidence interval 0.905 to 1.003)]. The qualitative evaluation found the clinicians liked the intervention, used it as a supportive aid, especially with borderline cases but that it, did not always integrate well within the consultation flow and was used less over time. The economic evaluation found no evidence of a difference in mean National Health Service costs between arms; mean difference -£1999 (95% confidence interval -£6627 to 2630). Conclusions: The intervention was feasible and subjectively useful to practitioners, with no evidence of harm in terms of hospitalisations, but did not impact on antibiotic prescribing rates. Future work and limitations: Although the intervention does not appear to change prescribing behaviour, elements of the approach may be used in the design of future interventions. Trial registration: This trial is registered as ISRCTN11405239 (date assigned 20 April 2018) at www.controlled-trials.com (accessed 5 September 2022). Version 4.0 of the protocol is available at: https://www.journalslibrary.nihr.ac.uk/ (accessed 5 September 2022). Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment (NIHR award ref: 16/31/98) programme and is published in full in Health Technology Assessment; Vol. 27, No. 32. See the NIHR Funding and Awards website for further award information.
Coughs and colds (also known as respiratory tract infections) are the most common reason that children are taken to family doctors and nurses in primary care. These clinicians are not always sure how best to treat them and often use antibiotics 'just in case'. There are now concerns that clinicians are using antibiotics too often, and that this is increasing the number of resistant bugs (bacteria that cannot be killed by antibiotics). We wanted to see if using a scoring system of symptoms and signs of illness to help clinicians identify children very unlikely to need hospital care as well as listening to parents' concerns and giving them a personalised leaflet with care and safety advice, reduced antibiotic use. We recruited practices rather than patients, so did not need individual patient consent. The two main outcomes were the rate of antibiotics dispensed for children and number of children admitted to hospital for respiratory tract infections, using routinely collected data for 09-year-olds. We recruited 294 general practitioner practices, which was 95% of the total needed; 144 were asked to use the intervention and 150 to continue providing usual care (controls); only 12 practices subsequently withdrew (6 related to the pandemic). The average number of times the intervention was used was 70 per practice (by an average of 9 clinicians) over 12 months. There was no evidence that the antibiotic dispensing rate in the intervention practices differed from control practices. Further analyses showed an overall reduction in dispensing levels and intervention usage during the pandemic. The rate of hospitalisation for respiratory tract infection in the intervention practices was similar to the control practices. In the interviews, we found that clinicians liked the intervention and used it as a supportive aid during consultations, especially for borderline cases, rather than a tool to change prescribing behaviour.
Assuntos
Antibacterianos , Infecções Respiratórias , Criança , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Antibacterianos/uso terapêutico , Tomada de Decisão Clínica , Medicina Estatal , Incerteza , Infecções Respiratórias/tratamento farmacológico , Tosse/tratamento farmacológicoRESUMO
OBJECTIVES: Conducting randomised controlled trials (RCTs) in primary care is challenging; recruiting patients during time-limited or remote consultations can increase selection bias and physical access to patients' notes is costly and time-consuming. We investigated barriers and facilitators to running a more efficient design. DESIGN: An RCT aiming to reduce antibiotic prescribing among children presenting with acute cough and a respiratory tract infection (RTI) with a clinician-focused intervention, embedded at the practice level. By using aggregate level, routinely collected data for the coprimary outcomes, we removed the need to recruit individual participants. SETTING: Primary care. PARTICIPANTS: Baseline data from general practitioner practices and interviews with individuals from Clinical Research Networks (CRNs) in England who helped recruit practices and Clinical Commission Groups (CCGs) who collected outcome data. INTERVENTION: The intervention included: (1) explicit elicitation of parental concerns, (2) a prognostic algorithm to identify children at low risk of hospitalisation and (3) provision of a printout for carers including safety-netting advice. COPRIMARY OUTCOMES: For 0-9 years old-(1) Dispensing data for amoxicillin and macrolide antibiotics and (2) hospital admission rate for RTI. RESULTS: We recruited 294 of the intended 310 practices (95%) representing 336 496 registered 0-9 years old (5% of all 0-9 years old children). Included practices were slightly larger, had slightly lower baseline prescribing rates and were located in more deprived areas reflecting the national distribution. Engagement with CCGs and their understanding of their role in this research was variable. Engagement with CRNs and installation of the intervention was straight-forward although the impact of updates to practice IT systems and lack of familiarity required extended support in some practices. Data on the coprimary outcomes were almost 100%. CONCLUSIONS: The infrastructure for trials at the practice level using routinely collected data for primary outcomes is viable in England and should be promoted for primary care research where appropriate. TRIAL REGISTRATION NUMBER: ISRCTN11405239.
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Medicina Geral , Infecções Respiratórias , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Inglaterra , Humanos , Lactente , Recém-Nascido , Atenção Primária à Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções Respiratórias/tratamento farmacológicoRESUMO
Plant oils containing ω-7 fatty acids (FAs; palmitoleic 16:1Δ(9) and cis-vaccenic 18:1Δ(11)) have potential as sustainable feedstocks for producing industrially important octene via metathesis chemistry. Engineering plants to produce seeds that accumulate high levels of any unusual FA has been an elusive goal. We achieved high levels of ω-7 FA accumulation by systematic metabolic engineering of Arabidopsis (Arabidopsis thaliana). A plastidial 16:0-ACP desaturase has been engineered to convert 16:0 to 16:1Δ(9) with specificity >100-fold than that of naturally occurring paralogs, such as that from cat's claw vine (Doxantha unguis-cati). Expressing this engineered enzyme (Com25) in seeds increased ω-7 FA accumulation from <2% to 14%. Reducing competition for 16:0-ACP by down-regulating the ß-ketoacyl-ACP synthase II 16:0 elongase further increased accumulation of ω-7 FA to 56%. The level of 16:0 exiting the plastid without desaturation also increased to 21%. Coexpression of a pair of fungal 16:0 desaturases in the cytosol reduced the 16:0 level to 11% and increased ω-7 FA to as much as 71%, equivalent to levels found in Doxantha seeds.
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Ácidos Graxos/metabolismo , Plantas/metabolismo , Sementes/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Plantas/enzimologiaRESUMO
INTRODUCTION: Respiratory tract infections (RTIs) in children are common and present major resource implications for primary care. Unnecessary use of antibiotics is associated with the development and proliferation of antimicrobial resistance. In 2016, the National Institute for Health Research (NIHR)-funded 'TARGET' programme developed a prognostic algorithm to identify children with acute cough and RTI at very low risk of 30-day hospitalisation and unlikely to need antibiotics. The intervention includes: (1) explicit elicitation of parental concerns, (2) the results of the prognostic algorithm accompanied by prescribing guidance and (3) provision of a printout for carers including safety netting advice. The CHIldren's COugh feasibility study suggested differential recruitment of healthier patients in control practices. This phase III 'efficiently designed' trial uses routinely collected data at the practice level, thus avoiding individual patient consent. The aim is to assess whether embedding a multifaceted intervention into general practitioner (GP) practice Information Technology (IT) systems will result in reductions of antibiotic prescribing without impacting on hospital attendance for RTI. METHODS AND ANALYSIS: The coprimary outcomes are (1) practice rate of dispensed amoxicillin and macrolide antibiotics, (2) hospital admission rate for RTI using routinely collected data by Clinical Commissioning Groups (CCGs). Data will be collected for children aged 0-9 years registered at 310 practices (155 intervention, 155 usual care) over a 12-month period. Recruitment and randomisation of practices (using the Egton Medical Information Systems web data management system) is conducted via each CCG stratified for children registered and baseline dispensing rates of each practice. Secondary outcomes will explore intervention effect modifiers. Qualitative interviews will explore intervention usage. The economic evaluation will be limited to a between-arm comparison in a cost-consequence analysis. ETHICS AND DISSEMINATION: Research ethics approval was given by London-Camden and Kings Cross Research Ethics Committee (ref:18/LO/0345). This manuscript refers to protocol V.4.0. Results will be disseminated through peer-reviewed journals and international conferences. TRIAL REGISTRATION NUMBER: ISRCTN11405239.
Assuntos
Tosse , Infecções Respiratórias , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Tosse/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Londres , Atenção Primária à Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções Respiratórias/tratamento farmacológicoRESUMO
Compared to traditional means, modern DNA assembly methods allow cloning of large, multigenic vectors for plant transformation in rapid fashion. These methods are often robust and efficient and can assemble multiple DNA fragments into a single vector in one reaction. Here we describe the use of an automated DNA assembly platform for the generation of complex, multigenic T-DNA binary vectors using a hierarchical Golden Gate cloning strategy. These DNA constructs contained diverse DNA elements for the expression of multiple genes for trait stacking in the crop of interest. This platform streamlines the DNA assembly and validation process through high-efficiency cloning methods, integrated automation equipment, and increased throughput. The implementation of this platform removes bottlenecks for routine molecular biology and opens new possibilities for downstream experimental idea testing.
Assuntos
Clonagem Molecular/métodos , Vetores Genéticos/genética , Família Multigênica/genética , Plantas Geneticamente Modificadas/genética , Escherichia coli/genética , Plasmídeos/genética , Plasmídeos/isolamento & purificação , Biologia Sintética/instrumentação , Biologia Sintética/métodos , Transformação Bacteriana/genéticaRESUMO
INTRODUCTION: Circulating prostaglandin E2 levels are elevated in acutely decompensated cirrhosis and have been shown to contribute to immune suppression. Albumin binds to and inactivates this immune-suppressive lipid mediator. Human albumin solution (HAS) could thus be repurposed as an immune-restorative drug in these patients.This is a phase III randomised controlled trial (RCT) to verify whether targeting a serum albumin level of ≥35 g/L in hospitalised patients with decompensated cirrhosis using repeated intravenous infusions of 20% HAS will reduce incidence of infection, renal dysfunction and mortality for the treatment period (maximum 14 days or discharge if <14 days) compared with standard medical care. METHODS AND ANALYSIS: Albumin To prevenT Infection in chronic liveR failurE stage 2 is a multicentre, open-label, interventional RCT. Patients with decompensated cirrhosis admitted to the hospital with a serum albumin of <30 g/L are eligible, subject to exclusion criteria. Patients randomised to intravenous HAS will have this administered, according to serum albumin levels, for up to 14 days or discharge. The infusion protocol aims to increase serum albumin to near-normal levels.The composite primary endpoint is: new infection, renal dysfunction or mortality within the trial treatment period. Secondary endpoints include mortality at up to 6 months, incidence of other organ failures, cost-effectiveness and quality of life outcomes and time to liver transplant. The trial will recruit 866 patients at more than 30 sites across the UK. ETHICSANDDISSEMINATION: Research ethics approval was given by the London-Brent research ethics committee (ref: 15/LO/0104). The clinical trials authorisation was issued by the medicines and healthcare products regulatory agency (ref: 20363/0350/001-0001). The trial is registered with the European Medicines Agency (EudraCT 2014-002300-24) and has been adopted by the National Institute for Health Research (ISRCTN 14174793). This manuscript refers to version 6.0 of the protocol. Results will be disseminated through peer-reviewed journals and international conferences. Recruitment of the first participant occurred on 25 January 2016.
Assuntos
Infecções Bacterianas/prevenção & controle , Infecção Hospitalar/prevenção & controle , Doença Hepática Terminal/terapia , Albumina Sérica Humana/uso terapêutico , Ensaios Clínicos Fase III como Assunto , Doença Hepática Terminal/complicações , Humanos , Hospedeiro Imunocomprometido , Infusões Intravenosas , Cirrose Hepática/complicações , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Renal/prevenção & controle , Albumina Sérica/análiseRESUMO
The molecular basis of transgene susceptibility to silencing is poorly characterized in plants; thus, we evaluated several transgene design parameters as means to reduce heritable transgene silencing. Analyses of Arabidopsis plants with transgenes encoding a microalgal polyunsaturated fatty acid (PUFA) synthase revealed that small RNA (sRNA)-mediated silencing, combined with the use of repetitive regulatory elements, led to aggressive transposon-like silencing of canola-biased PUFA synthase transgenes. Diversifying regulatory sequences and using native microalgal coding sequences (CDSs) with higher GC content improved transgene expression and resulted in a remarkable trans-generational stability via reduced accumulation of sRNAs and DNA methylation. Further experiments in maize with transgenes individually expressing three crystal (Cry) proteins from Bacillus thuringiensis (Bt) tested the impact of CDS recoding using different codon bias tables. Transgenes with higher GC content exhibited increased transcript and protein accumulation. These results demonstrate that the sequence composition of transgene CDSs can directly impact silencing, providing design strategies for increasing transgene expression levels and reducing risks of heritable loss of transgene expression.
Assuntos
Arabidopsis/genética , Sequência Rica em GC , Inativação Gênica , Interferência de RNA , RNA de Plantas/metabolismo , Transgenes , Metilação de DNA , Elementos de DNA Transponíveis , DNA de Plantas/metabolismo , Ácido Graxo Sintase Tipo II/genética , Ácidos Graxos Insaturados/genética , Genes de Plantas , Zea mays/genéticaRESUMO
Dietary omega-3 long-chain polyunsaturated fatty acids (LC-PUFAs), docosahexaenoic acid (DHA, C22:6) and eicosapentaenoic acid (EPA, C20:5) are usually derived from marine fish. Although production of both EPA and DHA has been engineered into land plants, including Arabidopsis, Camelina sativa and Brassica juncea, neither has been produced in commercially relevant amounts in a widely grown crop. We report expression of a microalgal polyketide synthase-like PUFA synthase system, comprising three multidomain polypeptides and an accessory enzyme, in canola (Brassica napus) seeds. This transgenic enzyme system is expressed in the cytoplasm, and synthesizes DHA and EPA de novo from malonyl-CoA without substantially altering plastidial fatty acid production. Furthermore, there is no significant impact of DHA and EPA production on seed yield in either the greenhouse or the field. Canola oil processed from field-grown grain contains 3.7% DHA and 0.7% EPA, and can provide more than 600 mg of omega-3 LC-PUFAs in a 14 g serving.
Assuntos
Brassica napus/metabolismo , Ácidos Docosa-Hexaenoicos/química , Melhoramento Genético/métodos , Microalgas/fisiologia , Óleos de Plantas/metabolismo , Policetídeo Sintases/metabolismo , Brassica napus/genética , Ácidos Docosa-Hexaenoicos/isolamento & purificação , Ácidos Docosa-Hexaenoicos/metabolismo , Óleos de Plantas/análise , Óleos de Plantas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Policetídeo Sintases/genética , Engenharia de Proteínas/métodos , Óleo de Brassica napusRESUMO
Approximately 20% of unselected cases and 30% cytogenetically diploid cases of acute myeloid leukemia (AML) and 80% of grade II-III gliomas and secondary glioblastomas carry mutations in the isocitrate dehydrogenase (IDH) 1 and 2 genes. IDH1/2 mutations prevent oxidative decarboxylation of isocitrate to α-ketoglutarate (α-KG) and modulate the function of IDH (neomorphic activity) thereby facilitating reduction of α-KG to D-2-hydroxyglutarate (D-2HG), a putative oncometabolite. D-2HG is thought to act as a competitive inhibitor of α-KG-dependent dioxygenases that include prolyl hydroxylases and chromatin-modifying enzymes. The end result is a global increase of cellular DNA hypermethylation and alterations of the cellular epigenetic state, which has been proposed to play a role in the development of a variety of tumors. In this review, we provide an update on potential molecular mechanisms linking IDH1/2 mutations and the resulting oncometabolite, D-2HG, with malignant transformation. In addition, in patients with AML and glioma we focus on the associations between IDH1/2 mutations and clinical, morphologic, cytogenetic, and molecular characteristics.
RESUMO
We report an extremely rare case with a total of 50 fibroadenomas simultaneously presented in bilateral breasts and left axillary accessory breast, up to 8 cm in size, in a 20 year-old Chinese woman. The histopathologic and immunophenotypic features of the fibroadenomas are described and possible underlying pathogenesis is discussed. To our knowledge, this is the first case with such a large number of bilateral multiple breast fibroadenomas in a young female reported in the literature.