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The three-dimensional positions of atoms in protein molecules define their structure and their roles in biological processes. The more precisely atomic coordinates are determined, the more chemical information can be derived and the more mechanistic insights into protein function may be inferred. Electron cryo-microscopy (cryo-EM) single-particle analysis has yielded protein structures with increasing levels of detail in recent years1,2. However, it has proved difficult to obtain cryo-EM reconstructions with sufficient resolution to visualize individual atoms in proteins. Here we use a new electron source, energy filter and camera to obtain a 1.7 Å resolution cryo-EM reconstruction for a human membrane protein, the ß3 GABAA receptor homopentamer3. Such maps allow a detailed understanding of small-molecule coordination, visualization of solvent molecules and alternative conformations for multiple amino acids, and unambiguous building of ordered acidic side chains and glycans. Applied to mouse apoferritin, our strategy led to a 1.22 Å resolution reconstruction that offers a genuine atomic-resolution view of a protein molecule using single-particle cryo-EM. Moreover, the scattering potential from many hydrogen atoms can be visualized in difference maps, allowing a direct analysis of hydrogen-bonding networks. Our technological advances, combined with further approaches to accelerate data acquisition and improve sample quality, provide a route towards routine application of cryo-EM in high-throughput screening of small molecule modulators and structure-based drug discovery.
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Apoferritinas/química , Apoferritinas/ultraestrutura , Microscopia Crioeletrônica/instrumentação , Microscopia Crioeletrônica/métodos , Receptores de GABA-A/química , Receptores de GABA-A/ultraestrutura , Imagem Individual de Molécula/métodos , Animais , Microscopia Crioeletrônica/normas , Descoberta de Drogas , Humanos , Camundongos , Modelos Moleculares , Polissacarídeos/química , Polissacarídeos/ultraestrutura , Imagem Individual de Molécula/normasRESUMO
Perinatal asphyxia (PA) and hypoxic-ischemic encephalopathy can result in severe, long-lasting neurological deficits. In vitro models, such as oxygen-glucose deprivation (OGD), are used experimentally to investigate neuronal response to metabolic stress. However, multiple variables can affect the severity level of OGD/PA and may confound any measured treatment effect. Oxytocin (OXT) has emerged as a potential neuroprotective agent against the deleterious effects of PA. Previous studies have demonstrated OXT's potential to enhance neuronal survival in immature hippocampal cultures exposed to OGD, possibly by modulating gamma-aminobutyric acid-A receptor activity. Moreover, OXT's precise impact on developing hippocampal neurons under different severities of OGD/PA remains uncertain. In this study, we investigated the effects of OXT (0.1 µM and 1 µM) on 7-day-old primary rat hippocampal cultures subjected to 2 h OGD/sham normoxic conditions. Cell culture viability was determined using the resazurin assay. Our results indicate that the efficacy of 1 µM OXT treatment varied according to the severity of the OGD-induced lesion, exhibiting a protective effect (p = 0.022) only when cellular viability dropped below 49.41% in non-treated OGD cultures compared to normoxic ones. Furthermore, administration of 0.1 µM OXT did not yield significant effects, irrespective of lesion severity (p > 0.05). These findings suggest that 1 µM OXT treatment during OGD confers neuroprotection exclusively in severe lesions in hippocampal neurons after 7 days in vitro. Further research is warranted to elucidate the mechanisms involved in OXT-mediated neuroprotection.
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BACKGROUND: Anaesthesiologists deliver an increasing amount of patient care and often work long hours in operating theatres and intensive care units, with frequent on-calls and insufficient rest in between. In the long term, this will negatively influence mental and physical health and well being. As fatigue becomes more prevalent, this has predictable implications for patient safety and clinical effectiveness. 1. OBJECTIVE: This study aimed to evaluate the prevalence, severity, causes and implications of work-related fatigue amongst specialist anaesthesiologists. DESIGN: An online survey of specialist anaesthesiologists. PARTICIPANTS: The survey was sent to anaesthesiologists in 42 European countries by electronic mail. MAIN OUTCOME MEASURES: Responses from a 36-item online survey assessed work-related fatigue and its impact on anaesthesiologists in European countries. RESULTS: Work-related fatigue was experienced in 91.6% of the 1508 respondents from 32 European countries. Fatigue was caused by their working patterns, clinical and nonclinical workloads, staffing issues and excessive work hours. Over 70% reported that work-related fatigue negatively impacted on their physical and mental health, emotional well being and safe commuting. Most respondents did not feel supported by their organisation to maintain good health and well being. CONCLUSION: Work-related fatigue is a significant and widespread problem amongst anaesthesiologists. More education and increased awareness of fatigue and its adverse effects on patient safety, staff well being and physical and mental health are needed. Departments should ensure that their rotas and job plans comply with the European Working Time Directive (EWTD) and introduce a fatigue risk management system to mitigate the effects of fatigue.
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Anestesiologistas , Fadiga , Humanos , Europa (Continente)/epidemiologia , Inquéritos e Questionários , Fadiga/diagnóstico , Fadiga/epidemiologiaRESUMO
BACKGROUND: There is a growing awareness of the effects of fatigue on trainee wellbeing and health. Trainees in anaesthesiology and intensive care work long hours, switching work schedules frequently with insufficient rest. This may have unwanted long-term effects on mental and physical health and emotional well being, resulting in burnout and affecting patient safety. OBJECTIVE: The study aimed to evaluate the prevalence, severity, causes and effects of work-related fatigue in trainees in anaesthesiology and intensive care. DESIGN: Online survey of trainees in anaesthesiology and intensive care. SETTINGS: A total of 31 countries within Europe were included in the survey. PARTICIPANTS: European anaesthesiology and intensive care trainees who responded to an invitation to take part by electronic mail or through social media. MAIN OUTCOME MEASURES: Responses from a 29-item online survey to assess the realities within European countries with regards to work-related fatigue. RESULTS: One thousand and two hundred trainees from 31 European countries answered the survey demonstrating that an alarming number of trainees were fatigued by their working patterns and night shifts. Trainees reported effects on personal well being, safe commuting and potential for clinical errors. Respondents described a lack of support from hospitals and management for recovery during and after night shifts. CONCLUSION: Fatigue among trainees in anaesthesiology and intensive care has a significant impact on their well being and potentially, on the incidence of clinical errors. Current measures from authorities and hospital management are not sufficient to prevent serious fatigue, and therefore a fatigue risk management system should be considered. Failure to address this issue might lead to a further decline in trainees' wellbeing, their capacity to work in the speciality in the future, and potentially increase patient care errors.
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Anestesiologia , Humanos , Europa (Continente)/epidemiologia , Fadiga/diagnóstico , Fadiga/epidemiologia , Cuidados Críticos , Assistência ao Paciente , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The epidemiology of critically ill patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be different worldwide. Despite similarities in medicine quality and formation, there are also significant differences concerning healthcare and ICU organisation, staffing, financial resources and population compliance and adherence. Large cohort data of critically ill patients from Central and Eastern Europe are also lacking. OBJECTIVES: The study objectives were to describe the clinical characteristics of patients admitted to Romanian ICUs with SARS-CoV-2 infection and to identify the factors associated with ICU mortality. DESIGN: Prospective, cohort, observational study. SETTING: National recruitment, multicentre study, between March 2020 to March 2021. PATIENTS: All patients with SARS-CoV-2 infection admitted to Romanian ICUs were eligible. There were no exclusion criteria. INTERVENTION: None. MAIN OUTCOME MEASURE: ICU mortality. RESULTS: The statistical analysis included 9058 patients with definitive ICU outcome. The multivariable mixed effects logistic regression model found that age [odds ratio (OR) 1.27; 95% confidence interval (CI), 1.23 to 1.31], male gender (OR 1.21; 95% CI 1.05 to 1.4), medical history of neoplasia (OR 1.74; 95% CI, 1.36 to 2.22), chronic kidney disease (OR 1.54; 95% CI, 1.27 to 1.88), type II diabetes (OR 1.23; 95% CI, 1.06 to 1.43), chronic heart failure (OR 1.24; 95% CI, 1.03 to 1.49), dyspnoea (OR 1.3; 95% CI, 1.1 to 1.5), SpO2 less than 90% (OR 3; 95% CI, 2.5 to 3.5), admission SOFA score (OR 1.07; 95% CI, 1.05 to 1.09), acute respiratory distress syndrome (ARDS) on ICU admission (OR 1.35; 95% CI, 1.1 to 1.63) and the need for noninvasive (OR 1.8, 95% CI, 1.5 to 1.22) or invasive ventilation (OR 28; 95% CI, 22 to 35) and neuromuscular blockade (OR 3.5; 95% CI, 2.6 to 4.8), were associated with larger ICU mortality.Higher GCS on admission (OR 0.81; 95% CI, 0.79 to 0.83), treatment with hydroxychloroquine (OR 0.78; 95% CI, 0.64 to 0.95) and tocilizumab (OR 0.58; 95% CI, 0.48 to 0.71) were inversely associated with ICU mortality. CONCLUSION: The SARS-CoV-2 critically ill Romanian patients share common personal and clinical characteristics with published European cohorts. Public health measures and vaccination campaign should focus on patients at risk.
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COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , Masculino , SARS-CoV-2 , Estudos ProspectivosRESUMO
Punicic acid (PuA) is a polyunsaturated fatty acid with significant medical, biological, and nutraceutical properties. The primary source of punicic acid is the pomegranate seed oil obtained from fruits of trees that are mainly cultivated in subtropical and tropical climates. To establish sustainable production of PuA, various recombinant microorganisms and plants have been explored as platforms with limited efficiencies. In this study, the oleaginous yeast Yarrowia lipolytica was employed as a host for PuA production. First, growth and lipid accumulation of Y. lipolytica were evaluated in medium supplemented with pomegranate seed oil, resulting in the accumulation of lipids up to 31.2%, consisting of 22% PuA esterified in the fraction of glycerolipids. In addition, lipid-engineered Y. lipolytica strains, transformed with the bifunctional fatty acid conjugase/desaturase from Punica granatum (PgFADX), showed the ability to accumulate PuA de novo. PuA was detected in both polar and neutral lipid fractions, especially in phosphatidylcholine and triacylglycerols. Promoter optimization for PgFADX expression resulted in improved accumulation of PuA from 0.9 to 1.8 mg/g of dry cell weight. The best-producing strain expressing PgFADX under the control of a strong erythritol-inducible promoter produced 36.6 mg/L PuA. These results demonstrate that the yeast Y. lipolytica is a promising host for PuA production.
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Yarrowia , Ácidos Graxos Dessaturases/metabolismo , Ácidos Linolênicos/metabolismo , Óleos de Plantas/metabolismo , Ácidos Graxos/metabolismoRESUMO
KEY POINTS: Baclofen is a GABAB agonist prescribed as a treatment for spasticity in stroke, brain injury and multiple sclerosis patients, who are often undergoing concurrent motor rehabilitation. Decreasing GABAergic inhibition is a key feature of motor learning and so there is a possibility that GABA agonist drugs, such as baclofen, could impair these processes, potentially impacting rehabilitation. Here, we examined the effect of 10 mg of baclofen, in 20 young healthy individuals, and found that the drug impaired retention of visuomotor learning with no significant effect on motor sequence learning. Overall baclofen did not alter transcranial magnetic stimulation-measured GABAB inhibition, although the change in GABAB inhibition correlated with aspects of visuomotor learning retention. Further work is needed to investigate whether taking baclofen impacts motor rehabilitation in patients. ABSTRACT: The GABAB agonist baclofen is taken daily as a treatment for spasticity by millions of stroke, brain injury and multiple sclerosis patients, many of whom are also undergoing motor rehabilitation. However, decreases in GABA are suggested to be a key feature of human motor learning, which raises questions about whether drugs increasing GABAergic activity may impair motor learning and rehabilitation. In this double-blind, placebo-controlled study, we investigated whether a single 10 mg dose of the GABAB agonist baclofen impaired motor sequence learning and visuomotor learning in 20 young healthy participants of both sexes. Participants trained on visuomotor and sequence learning tasks using their right hand. Transcranial magnetic stimulation (TMS) measures of corticospinal excitability, GABAA (short-interval intracortical inhibition, 2.5 ms) and GABAB (long-interval intracortical inhibition, 150 ms) receptor activation were recorded from left M1. Behaviourally, baclofen caused a significant reduction of visuomotor aftereffect (F1,137.8 = 6.133, P = 0.014) and retention (F1,130.7 = 4.138, P = 0.044), with no significant changes to sequence learning. There were no overall changes to TMS measured GABAergic inhibition with this low dose of baclofen. This result confirms the causal importance of GABAB inhibition in mediating visuomotor learning and suggests that chronic baclofen use could negatively impact aspects of motor rehabilitation.
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Baclofeno , Estimulação Magnética Transcraniana , Baclofeno/farmacologia , Método Duplo-Cego , Feminino , Agonistas GABAérgicos/efeitos adversos , Humanos , Masculino , Receptores de GABA-BRESUMO
(1) Background: Triple negative breast cancer (TNBC) is a highly aggressive tumor, associated with high rates of early distant recurrence and short survival times, and treatment may require surgery, and thus anesthesia. The effects of anesthetic drugs on cancer progression are under scrutiny, but published data are controversial, and the involved mechanisms unclear. Anesthetic agents have been shown to modulate several molecular cascades, including PI3K/AKT/mTOR. AKT isoforms are frequently amplified in various malignant tumors and associated with malignant cell survival, proliferation and invasion. Their activation is often observed in human cancers and is associated with decreased survival rate. Certain anesthetics are known to affect hypoxia cell signaling mechanisms by upregulating hypoxia-inducible factors (HIFs). (2) Methods: MCF-10A and MDA-MB 231 cells were cultivated and CellTiter-Blue® Cell Viability assay, 2D and 3D matrigel assay, immunofluorescence assays and gene expressions assay were performed after exposure to different sevoflurane concentrations. (3) Results: Sevoflurane exposure of TNBC cells results in morphological and behavioral changes. Sevoflurane differently influences the AKT isoforms expression in a time-dependent manner, with an important early AKT3 upregulation. The most significant effects occur at 72 h after 2 mM sevoflurane treatment and consist in increased viability, proliferation and aggressiveness and increased vimentin and HIF expression. (4) Conclusions: Sevoflurane exposure during surgery may contribute to cancer recurrence via AKT3 induced epithelial-mesenchymal transition (EMT) and by all three AKT isoforms enhanced cancer cell survival and proliferation.
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Proliferação de Células/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sevoflurano/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Anestésicos Inalatórios/farmacologia , Técnicas de Cultura de Células em Três Dimensões/métodos , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Filamentos Intermediários/efeitos dos fármacos , Filamentos Intermediários/metabolismo , Isoformas de Proteínas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
Nanoviridae is a family of plant viruses (nanovirids) whose members have small isometric virions and multipartite, circular, single-stranded (css) DNA genomes. Each of the six (genus Babuvirus) or eight (genus Nanovirus) genomic DNAs is 0.9-1.1 kb and is separately encapsidated. Many isolates are associated with satellite-like cssDNAs (alphasatellites) of 1.0-1.1 kb. Hosts are eudicots, predominantly legumes (genus Nanovirus), and monocotyledons, predominantly in the order Zingiberales (genus Babuvirus). Nanovirids require a virus-encoded helper factor for transmission by aphids in a circulative, non-propagative manner. This is a summary of the ICTV Report on the family Nanoviridae, which is available at ictv.global/report/nanoviridae.
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Nanoviridae/classificação , Nanoviridae/fisiologia , Animais , Afídeos/virologia , Babuvirus/classificação , Babuvirus/genética , Babuvirus/fisiologia , Babuvirus/ultraestrutura , DNA Viral/genética , Fabaceae/virologia , Genoma Viral , Insetos Vetores/virologia , Nanoviridae/genética , Nanoviridae/ultraestrutura , Nanovirus/classificação , Nanovirus/genética , Nanovirus/fisiologia , Nanovirus/ultraestrutura , Doenças das Plantas/virologia , Proteínas Virais/genética , Vírion/ultraestrutura , Replicação Viral , Zingiberales/virologiaRESUMO
The aim of the study was to outline technical difficulties and procedural complications of using partially covered esophageal self-expandable metal stents (SEMSs) in malignant esophageal respiratory fistulas (ERFs) as a palliative treatment option. In this study, 150 patients with malignant dysphagia underwent treatment with SEMSs. A total of 36 ERFs were detected through endoscopic or clinical assessment. Complete fistula sealing with SEMSs was possible in 35 of the 36 patients. The majority of fistulas were diagnosed in male patients with advanced esophageal cancer. All of them presented with prolonged dysphagia and cachexia. Stent migration or tumoral overgrowth was identified in 6 cases with recurrent dysphagia, and required a second stent insertion. SEMSs were highly efficient in 98% of the patients studied with ERFs, with successfully sealed ERFs after the first attempt, with an overall median survival rate of 92 days. The technique of esophageal SEMS placement is simple and can be rapidly mastered. Patients with ERFs have a respiratory shunt that makes intubation difficult and is often avoided. Restoring oral feeding increased the patient quality of life. SEMS placement is generally safe, but has few associated postoperative complications.
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Transtornos de Deglutição , Estenose Esofágica , Transtornos de Deglutição/complicações , Transtornos de Deglutição/terapia , Estenose Esofágica/etiologia , Estenose Esofágica/cirurgia , Humanos , Masculino , Cuidados Paliativos/métodos , Qualidade de Vida , Estudos Retrospectivos , Stents/efeitos adversos , Resultado do TratamentoRESUMO
Water retention and intercompartmental redistribution occur frequently in association with adverse postoperative outcomes, yet the available strategies for non-invasive assessment are limited. One such approach for evaluating body water composition in various circumstances is bio-electrical impedance analysis (BIA). This study aims to appraise the usefulness of the Body Composition Monitor (BCM, Fresenius Medical Care, Germany) in assessing body fluid composition and intercompartmental shifts before and after open major abdominal surgery. This prospective, clinician blinded observational study enrolled all the patients scheduled consecutively for elective major open abdominal surgery during a 1-year period starting from January 1st, 2016. BIA parameters-total body water (TBW), extracellular water (ECW), intracellular water (ICW), absolute fluid overload (AFO), and relative fluid overload (RFO) were measured before and after surgery. The results were compared with fluid balance and outcome parameters such as organ dysfunction, ICU-and hospital length of stay (-LOS). The study population included 71 patients aged 60.2 ± 12 of whom 60.6% men and with a BMI of 26.3 ± 5.1 kg/m2. Postoperative acute kidney injury, respiratory dysfunction, and infections occurred in 14.0%, 19.7% and 28.1% of cases, respectively. The median LOS in ICU was 20 h and the hospital-LOS was 10 days. Positive intraoperative fluid balance (2.4 ± 1.0 L) resulted in a significant increase of TBW (1.4 ± 2.4 L) and of ECW (1.4 ± 1.2 L). Intraoperative fluid balance significantly correlated with TBW change (r = 0.23, p = 0.04) and with AFO change (r = 0.31, p < 0.01). A significant correlation was found between pre- and postoperative AFO and RFO on one hand, and ICU-LOS on the other. BIA may be a useful tool for the perioperative assessment of volume status.
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Abdome/cirurgia , Composição Corporal , Impedância Elétrica , Unidades de Terapia Intensiva , Estudos Prospectivos , Procedimentos Cirúrgicos Operatórios/métodos , Desequilíbrio Hidroeletrolítico/fisiopatologia , Idoso , Índice de Massa Corporal , Água Corporal , Peso Corporal , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Período Pós-Operatório , Água , Equilíbrio HidroeletrolíticoRESUMO
Background: Both anemia and blood transfusion are now considered independent risk factors for poor outcome in colorectal cancer patients. Severe anemia can increase tumor aggressiveness and blood transfusion may induce immunosuppression and promote cancer recurrence. Specific Patient Blood Management (PBM) strategies for oncological surgical patients are insufficiently defined and recommended. Primary objectives: Evaluation of the perioperative anemia prevalence and transfusion rate in colorectal cancer patients. Secondary objectives: Sub-group analysis of anemic versus non-anemic patients and colon versus rectal cancer patients. Methods: We retrospectively reviewed records from all consecutive surgical oncological patients admitted between January and June 2017. We selected major lower abdominal surgical patients and then colorectal surgical patients. We evaluated the perioperative hemoglobin values dynamics (preoperative=Hb1, postoperative= Hb2, at discharge= Hb3), anemia prevalence and severity and transfusion rate. Statistical analysis used Student t test, Wilcoxon signed-rank and Chi-square tests from SPSS 17. Results: Of the 1284 patients screened, 546 patients were submitted to major lower abdominal surgery and 260 patients to colorectal cancer surgery. The mean age was 65.6 +- 11.1 years, 57.7% males. The perioperative dynamics of hemoglobin was Hb1/Hb2/Hb3 =12/10.6/10.4 g/dL. Anemia prevalence was 52.3/82.3/82.6% preoperatively/postoperatively/at hospital discharge. Global transfusion rate was 23.8%, with pre/intra/postoperative distribution of 2.3/11.9/10.8%. Anemic patients were older (p=0.005), with a higher transfusion rate (p 0.001) and a longer hospital LOS (p=0.04). Colon cancer patients had lower Hb values (p=0.001) and higher prevalence of preoperative anemia (p=0.001) comparing with rectal cancer patients. Conclusions: The analysis of this cohort of colorectal cancer patients identified an increased prevalence of anemia in all perioperative phases. There is an urgent need of PBM program implementation in this selected group of surgical patients.
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Anemia/terapia , Transfusão de Sangue , Neoplasias do Colo/terapia , Neoplasias Retais/terapia , Idoso , Anemia/diagnóstico , Anemia/etiologia , Neoplasias do Colo/complicações , Neoplasias do Colo/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Neoplasias Retais/complicações , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
The recent identification of a new nanovirus, pea necrotic yellow dwarf virus, from pea in Germany prompted us to survey wild and cultivated legumes for nanovirus infections in several European countries. This led to the identification of two new nanoviruses: black medic leaf roll virus (BMLRV) and pea yellow stunt virus (PYSV), each considered a putative new species. The complete genomes of a PYSV isolate from Austria and three BMLRV isolates from Austria, Azerbaijan and Sweden were sequenced. In addition, the genomes of five isolates of faba bean necrotic yellows virus (FBNYV) from Azerbaijan and Spain and those of four faba bean necrotic stunt virus (FBNSV) isolates from Azerbaijan were completely sequenced, leading to the first identification of FBNSV occurring in Europe. Sequence analyses uncovered evolutionary relationships, extensive reassortment and potential remnants of mixed nanovirus infections, as well as intra- and intercomponent recombination events within the nanovirus genomes. In some virus isolates, diverse types of the same genome component (paralogues) were observed, a type of genome complexity not described previously for any member of the family Nanoviridae. Moreover, infectious and aphid-transmissible nanoviruses from cloned genomic DNAs of FBNYV and BMLRV were reconstituted that, for the first time, allow experimental reassortments for studying the genome functions and evolution of these nanoviruses.
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Variação Genética , Genoma Viral , Nanoviridae/classificação , Nanoviridae/genética , Recombinação Genética , Análise de Sequência de DNA , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Europa (Continente) , Evolução Molecular , Fabaceae/virologia , Dados de Sequência Molecular , Nanoviridae/isolamento & purificação , Filogenia , Doenças das Plantas/virologiaRESUMO
Nucleic acid sensing is a 3 decades old but still challenging area of application for different biological sub-domains, from pathogen detection to single cell transcriptomics analysis. The many applications of nucleic acid detection and identification are mostly carried out by PCR techniques, sequencing, and their derivatives used at large scale. However, these methods' limitations on speed, cost, complexity and specificity have motivated the development of innovative detection methods among which nucleic acid biosensing technologies seem promising. Toehold switches are a particular class of RNA sensing devices relying on a conformational switch of secondary structure induced by the pairing of the detected trigger RNA with a de novo designed synthetic sensing mRNA molecule. Here we describe a streamlined methodology enabling the development of such a sensor for the RNA-mediated detection of an endangered plant species in a cell-free reaction system. We applied this methodology to help identify the rosewood Dalbergia maritima, a highly trafficked wood, whose protection is limited by the capacity of the authorities to distinguish protected logs from other unprotected but related species. The streamlined pipeline presented in this work is a versatile framework enabling cheap and rapid development of new sensors for custom RNA detection.
RESUMO
Nanoviruses are multipartite single-stranded DNA (ssDNA) plant viruses that cause important diseases of leguminous crops and banana. Little has been known about the variability and molecular evolution of these viruses. Here we report on the variability of faba bean necrotic stunt virus (FBNSV), a nanovirus from Ethiopia. We found mutation frequencies of 7.52 x 10(-4) substitutions per nucleotide in a field population of the virus and 5.07 x 10(-4) substitutions per nucleotide in a laboratory-maintained population derived thereof. Based on virus propagation for a period of more than 2 years, we determined a nucleotide substitution rate of 1.78 x 10(-3) substitutions per nucleotide per year. This high molecular evolution rate places FBNSV, as a representative of the family Nanoviridae, among the fastest-evolving ssDNA viruses infecting plants or vertebrates.
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Evolução Molecular , Nanovirus/genética , Mutação Puntual , DNA Viral/química , DNA Viral/genética , Etiópia , Dados de Sequência Molecular , Nanovirus/isolamento & purificação , Doenças das Plantas/virologia , Análise de Sequência de DNA , Vicia faba/virologiaRESUMO
Stroke affects millions of people worldwide each year, and stroke survivors are often left with motor deficits. Current therapies to improve these functional deficits are limited, making it a priority to better understand the pathophysiology of stroke recovery and find novel adjuvant options. The excitation-inhibition balance undergoes significant changes post-stroke, and the inhibitory neurotransmitter γ-aminobutyric acid (GABA) appears to play an important role in stroke recovery. In this review, we summarise the most recent studies investigating GABAergic inhibition at different stages of stroke. We discuss the proposed role of GABA in counteracting glutamate-mediated excitotoxicity in hyperacute stroke as well as the evidence linking decreased GABAergic inhibition to increased neuronal plasticity in early stroke. Then, we discuss two types of interventions that aim to modulate the excitation-inhibition balance to improve functional outcomes in stroke survivors: non-invasive brain stimulation (NIBS) and pharmacological interventions. Finding the optimal NIBS administration or adjuvant pharmacological therapies would represent an important contribution to the currently scarce therapy options.
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Increased inspiratory oxygen concentration is constantly used during the perioperative period of cancer patients to prevent the potential development of hypoxemia and to provide an adequate oxygen transport to the organs, tissues and cells. Although the primary tumours are surgically removed, the effects of perioperative hyperoxia exposure on distal micro-metastases and on circulating cancer cells can potentially play a role in cancer progression or recurrence. In clinical trials, hyperoxia seems to increase the rate of postoperative complications and, by delaying postoperative recovery, it can alter the return to intended oncological treatment. The effects of supplemental oxygen on the long-term mortality of surgical cancer patients offer, at this point, conflicting results. In experimental studies, hyperoxia effects on cancer biology were explored following multiple pathways. In cancer cell cultures and animal models, hyperoxia increases the production of reactive oxygen species (ROS) and increases the oxidative stress. These can be followed by the induction of the expression of Brain-derived neurotrophic factor (BDNF) and other molecules involved in angiogenesis and by the promotion of various degrees of epithelial mesenchymal transition (EMT).
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Many tasks require the skilled interaction of both hands, such as eating with knife and fork or keyboard typing. However, our understanding of the behavioural and neurophysiological mechanisms underpinning bimanual motor learning is still sparse. Here, we aimed to address this by first characterising learning-related changes of different levels of bimanual interaction and second investigating how beta tACS modulates these learning-related changes. To explore early bimanual motor learning, we designed a novel bimanual motor learning task. In the task, a force grip device held in each hand (controlling x- and y-axis separately) was used to move a cursor along a path of streets at different angles (0°, 22.5°, 45°, 67.5°, and 90°). Each street corresponded to specific force ratios between hands, which resulted in different levels of hand interaction, i.e., unimanual (Uni, i.e., 0°, 90°), bimanual with equal force (Bi eq , 45°), and bimanual with unequal force (Bi uneq 22.5°, 67.5°). In experiment 1, 40 healthy participants performed the task for 45 min with a minimum of 100 trials. We found that the novel task induced improvements in movement time and error, with no trade-off between movement time and error, and with distinct patterns for the three levels of bimanual interaction. In experiment 2, we performed a between-subjects, double-blind study in 54 healthy participants to explore the effect of phase synchrony between both sensorimotor cortices using tACS at the individual's beta peak frequency. The individual's beta peak frequency was quantified using electroencephalography. 20 min of 2 mA peak-to-peak amplitude tACS was applied during task performance (40 min). Participants either received in-phase (0° phase shift), out-of-phase (90° phase shift), or sham (3 s of stimulation) tACS. We replicated the behavioural results of experiment 1, however, beta tACS did not modulate motor learning. Overall, the novel bimanual motor task allows to characterise bimanual motor learning with different levels of bimanual interaction. This should pave the way for future neuroimaging studies to further investigate the underlying mechanism of bimanual motor learning.