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1.
Insect Biochem Mol Biol ; 165: 104059, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38101706

RESUMO

Blood feeding is a secondary adaptation in hematophagous bugs. Many proteins are secreted in the saliva that are devoted to coping with the host's defense and to process the blood meal. Digestive enzymes that are no longer required for a blood meal would be expected to be eventually lost. Yet, in many strictly hematophagous arthropods, α-amylase genes, which encode the enzymes that digest starch from plants, are still present and transcribed, including in the kissing bug Rhodnius prolixus (Hemiptera, Reduviidae) and its related species, which transmit the Chagas disease. We hypothesized that retaining α-amylase could be advantageous if the bugs occasionally consume plant tissues. We first checked that the α-amylase protein of Rhodnius robustus retains normal amylolytic activity. Then we surveyed hundreds of gut DNA extracts from the sylvatic R. robustus to detect traces of plants. We found plant DNA in 8% of the samples, mainly identified as Attalea palm trees, where R. robustus are usually found. We suggest that although of secondary importance in the blood-sucking bugs, α-amylase may be needed during occasional plant feeding and thus has been retained.


Assuntos
Doença de Chagas , Rhodnius , Triatoma , Animais , Rhodnius/genética , DNA , Triatoma/genética , alfa-Amilases/genética
2.
Eur Radiol Exp ; 7(1): 79, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087079

RESUMO

BACKGROUND: Spleen stiffness measurement (SSM) performed by transient elastography at 100 Hz is a novel technology for the evaluation of portal hypertension in advanced chronic liver disease, but technical aspects are lacking. We aimed to evaluate the intraexamination variability of SSM and to determine the best transient elastography protocol for obtaining robust measurements to be used in clinical practice. METHODS: We analyzed 253 SSM exams with up to 20 scans for each examination, performed between April 2021 and June 2022. All SSM results were evaluated according to different protocols by dividing data into groups of n measurements (from 2 to 19). Considering as reference the median SSM values across all the 20 measurements, we calculated the distribution of the absolute deviations of each protocol from the reference median. This analysis was repeated 1,000 times by resampling the data. Distributions were also stratified by etiology (chronic liver disease versus clinically significant portal hypertension) and different SSM ranges: < 25 kPa, 25-75, and > 75 kPa. RESULTS: Overall, we observed that the spleen stiffness exam had less variability if it exceeded 12 measurements, i.e., absolute deviations ≤ 5 kPa at 95% confidence. For exams with higher SSM values (> 75 kPa), as seen in clinically significant portal hypertension, at least 15 measurements are highly recommendable. CONCLUSIONS: Fifteen scans per examination should be considered for each SSM exam performed at 100 Hz to achieve a low intraexamination variability within a reasonable time in clinical practice. RELEVANCE STATEMENT: Performing at least 15 scans per examination is recommended for 100 Hz SSM in order to achieve a low intraexamination variability, in particular for values > 75 kPa compatible with clinically significant portal hypertension. KEY POINTS: • Spleen stiffness measurement by transient elastography is used for stratification in patients with portal hypertension. • At 100 Hz, this method may have intraexamination variability. • A minimum of 15 scans per examination achieves a low intraexamination variability.


Assuntos
Técnicas de Imagem por Elasticidade , Hipertensão Portal , Humanos , Baço/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Hipertensão Portal/diagnóstico por imagem
3.
R Soc Open Sci ; 10(5): 221255, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206965

RESUMO

In recent years, the scientific community has called for improvements in the credibility, robustness and reproducibility of research, characterized by increased interest and promotion of open and transparent research practices. While progress has been positive, there is a lack of consideration about how this approach can be embedded into undergraduate and postgraduate research training. Specifically, a critical overview of the literature which investigates how integrating open and reproducible science may influence student outcomes is needed. In this paper, we provide the first critical review of literature surrounding the integration of open and reproducible scholarship into teaching and learning and its associated outcomes in students. Our review highlighted how embedding open and reproducible scholarship appears to be associated with (i) students' scientific literacies (i.e. students' understanding of open research, consumption of science and the development of transferable skills); (ii) student engagement (i.e. motivation and engagement with learning, collaboration and engagement in open research) and (iii) students' attitudes towards science (i.e. trust in science and confidence in research findings). However, our review also identified a need for more robust and rigorous methods within pedagogical research, including more interventional and experimental evaluations of teaching practice. We discuss implications for teaching and learning scholarship.

4.
R Soc Open Sci ; 10(2): 210586, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36756069

RESUMO

Increased execution of replication studies contributes to the effort to restore credibility of empirical research. However, a second generation of problems arises: the number of potential replication targets is at a serious mismatch with available resources. Given limited resources, replication target selection should be well-justified, systematic and transparently communicated. At present the discussion on what to consider when selecting a replication target is limited to theoretical discussion, self-reported justifications and a few formalized suggestions. In this Registered Report, we proposed a study involving the scientific community to create a list of considerations for consultation when selecting a replication target in psychology. We employed a modified Delphi approach. First, we constructed a preliminary list of considerations. Second, we surveyed psychologists who previously selected a replication target with regards to their considerations. Third, we incorporated the results into the preliminary list of considerations and sent the updated list to a group of individuals knowledgeable about concerns regarding replication target selection. Over the course of several rounds, we established consensus regarding what to consider when selecting a replication target. The resulting checklist can be used for transparently communicating the rationale for selecting studies for replication.

5.
Am J Trop Med Hyg ; 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35576947

RESUMO

The genome size of five Rhodnius species (R. milesi, R. nasutus, R. neivai, R. prolixus, and R. robustus) and two Psammolestes species (P. coroedes and P. tertius) were estimated using flow cytometry and/or k-mer distributions in genome sequences. Phylogenetic generalized linear mixed models highlighted significant genome size variations among species and between sexes, with R. prolixus showing the largest genome. In this study we provide the first data on female genome size in Triatominae. For five species, female genome size did not differ from males, except for R. robustus, where females had smaller genomes. Genome size estimations based on the k-mer distribution method were less than those estimated from flow cytometry, but both methods exhibited the same pattern of sexual differences. Further genomic studies are needed to infer whether genome size variation could be an adaptive trait in Rhodnius.

6.
Psychol Med ; 51(16): 2752-2761, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34620261

RESUMO

Approval and prescription of psychotropic drugs should be informed by the strength of evidence for efficacy. Using a Bayesian framework, we examined (1) whether psychotropic drugs are supported by substantial evidence (at the time of approval by the Food and Drug Administration), and (2) whether there are systematic differences across drug groups. Data from short-term, placebo-controlled phase II/III clinical trials for 15 antipsychotics, 16 antidepressants for depression, nine antidepressants for anxiety, and 20 drugs for attention deficit hyperactivity disorder (ADHD) were extracted from FDA reviews. Bayesian model-averaged meta-analysis was performed and strength of evidence was quantified (i.e. BFBMA). Strength of evidence and trialling varied between drugs. Median evidential strength was extreme for ADHD medication (BFBMA = 1820.4), moderate for antipsychotics (BFBMA = 365.4), and considerably lower and more frequently classified as weak or moderate for antidepressants for depression (BFBMA = 94.2) and anxiety (BFBMA = 49.8). Varying median effect sizes (ESschizophrenia = 0.45, ESdepression = 0.30, ESanxiety = 0.37, ESADHD = 0.72), sample sizes (Nschizophrenia = 324, Ndepression = 218, Nanxiety = 254, NADHD = 189.5), and numbers of trials (kschizophrenia = 3, kdepression = 5.5, kanxiety = 3, kADHD = 2) might account for differences. Although most drugs were supported by strong evidence at the time of approval, some only had moderate or ambiguous evidence. These results show the need for more systematic quantification and classification of statistical evidence for psychotropic drugs. Evidential strength should be communicated transparently and clearly towards clinical decision makers.


Assuntos
Antipsicóticos , Transtorno do Deficit de Atenção com Hiperatividade , Humanos , Antipsicóticos/uso terapêutico , Teorema de Bayes , Psicotrópicos/uso terapêutico , Antidepressivos/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico
7.
Arch Toxicol ; 95(10): 3417-3424, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34458933

RESUMO

The identification of genotoxic agents and their potential for genotoxic alterations in an organism is crucial for risk assessment and approval procedures of the chemical and pharmaceutical industry. Classically, testing strategies for DNA or chromosomal damage focus on in vitro and in vivo (mainly rodent) investigations. In cell culture systems, the alkaline unwinding (AU) assay is one of the well-established methods for detecting the percentage of double-stranded DNA (dsDNA). By establishing a reliable lysis protocol, and further optimization of the AU assay for the model organism Caenorhabditis elegans (C. elegans), we provided a new tool for genotoxicity testing in the niche between in vitro and rodent experiments. The method is intended to complement existing testing strategies by a multicellular organism, which allows higher predictability of genotoxic potential compared to in vitro cell line or bacterial investigations, before utilizing in vivo (rodent) investigations. This also allows working within the 3R concept (reduction, refinement, and replacement of animal experiments), by reducing and possibly replacing animal testing. Validation with known genotoxic agents (bleomycin (BLM) and tert-butyl hydroperoxide (tBOOH)) proved the method to be meaningful, reproducible, and feasible for high-throughput genotoxicity testing, and especially preliminary screening.


Assuntos
Bleomicina/toxicidade , Instabilidade Genômica , Testes de Mutagenicidade/métodos , terc-Butil Hidroperóxido/toxicidade , Animais , Caenorhabditis elegans , Dano ao DNA/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Mutagênicos/toxicidade , Reprodutibilidade dos Testes
8.
PLoS One ; 16(7): e0255093, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34297766

RESUMO

BACKGROUND: Following testing in clinical trials, the use of remdesivir for treatment of COVID-19 has been authorized for use in parts of the world, including the USA and Europe. Early authorizations were largely based on results from two clinical trials. A third study published by Wang et al. was underpowered and deemed inconclusive. Although regulators have shown an interest in interpreting the Wang et al. study, under a frequentist framework it is difficult to determine if the non-significant finding was caused by a lack of power or by the absence of an effect. Bayesian hypothesis testing does allow for quantification of evidence in favor of the absence of an effect. FINDINGS: Results of our Bayesian reanalysis of the three trials show ambiguous evidence for the primary outcome of clinical improvement and moderate evidence against the secondary outcome of decreased mortality rate. Additional analyses of three studies published after initial marketing approval support these findings. CONCLUSIONS: We recommend that regulatory bodies take all available evidence into account for endorsement decisions. A Bayesian approach can be beneficial, in particular in case of statistically non-significant results. This is especially pressing when limited clinical efficacy data is available.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Tratamento Farmacológico da COVID-19 , COVID-19/epidemiologia , SARS-CoV-2 , Monofosfato de Adenosina/administração & dosagem , Alanina/administração & dosagem , Ensaios Clínicos como Assunto , Europa (Continente)/epidemiologia , Humanos , Resultado do Tratamento , Estados Unidos/epidemiologia
9.
J Anxiety Disord ; 78: 102357, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33588287

RESUMO

OBJECTIVE: This systematic review and meta-analysis aimed to clarify the association between social anxiety and affective (AE) and cognitive empathy (CE). METHODS: 1442 studies from PsycINFO, Medline, and EMBASE (inception-January 2020) were systematically reviewed. Included studies (N = 48) either predicted variance in empathy using social anxiety scores or compared empathy scores between socially anxious individuals and a control group. RESULTS: Social anxiety and AE were statistically significantly positively associated, k = 14, r = .103 (95%CI [.003, .203]), z = 2.03, p = .043. Sex (QM (2) = 18.79, p <  .0001), and type of measures (QM (1 = 7.34, p = .007) moderated the association. Correlations were significant for male samples (rmale = .316, (95%CI [.200, .432])) and studies using self-report measures (rself-report = .162 (95%CI [.070, .254])). Overall, social anxiety and CE were not significantly associated, k = 52, r =-.021 (95%CI [-.075, .034]), z= -0.74, p = .459. Sample type moderated the association (QM (1) = 5.03, p < .0001). For clinical samples the association was negative (rclinical= -.112, (95%CI [-.201, -.017]). CONCLUSION: There was evidence for a positive association between social anxiety and AE, but future studies are needed to verify the moderating roles of sex and type of measure. Besides, low CE might only hold for patients with SAD.


Assuntos
Empatia , Medo , Ansiedade , Humanos , Masculino , Autorrelato
10.
Front Psychiatry ; 11: 563287, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192682

RESUMO

Background: Meta-analyses suggest an increased prevalence of paternal depression during the perinatal period of around 10%. The relationship between paternal and maternal symptoms, however, has received little attention. Objective: To determine pooled estimates pertaining to the relationship between paternal and maternal depression during the perinatal period according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Data sources: Studies reporting on the relationship between depression in fathers and mothers between the first trimester and the first year following childbirth were identified using PubMed, PsycINFO, and EMBASE for the period between November 2009 and February 2020. Study selection: A total of 28 primary, empirical studies published in English or German, reporting effect estimates for the relationship of depression in mother-father/partner dyads, involving 11,593 couples, were included. Ten studies included multiple assessments, resulting in 64 extracted effects. Analysis: Information on correlations and odds ratios were extracted. Four random-effects analyses were conducted for the pooled association between paternal and maternal depression: (a) during the prenatal and (b) during the postnatal period, as well as for the prospective relationships between (c) paternal depression and maternal depression at a later timepoint, and (d) vice versa. Models were specified as restricted maximum-likelihood estimation. Heterogeneity was assessed using H 2 and I 2. Funnel plots, the Egger method, and the trim-and-fill test were used to assess publication bias. Sensitivity analyses with and without studies for which we approximated r were conducted. Data synthesis: With substantial heterogeneity, positive associations were found between paternal and maternal depression (a) during pregnancy (r = 0.238), (b) in the postnatal period (r = 0.279), as well as for the prospective relationship between (c) paternal and later maternal depression (r = 0.192), and (d) maternal and later paternal depression (r = 0.208). Conclusion: Paternal depression showed positive correlations with maternal depression across the perinatal period. Given notable methodological and cultural heterogeneity and limitations of individual studies, it was not possible to further identify determining or moderating factors. Increasing evidence for implications of parental depression for child development warrants further scientific attention.

11.
J Trace Elem Med Biol ; 57: 21-27, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31546209

RESUMO

BACKGROUND AND AIM: When exceeding the homeostatic range, manganese (Mn) might cause neurotoxicity, characteristic of the pathophysiology of several neurological diseases. Although the underlying mechanism of its neurotoxicity remains unclear, Mn-induced oxidative stress contributes to disease etiology. DNA damage caused by oxidative stress may further trigger dysregulation of DNA-damage-induced poly(ADP-ribosyl)ation (PARylation), which is of central importance especially for neuronal homeostasis. Accordingly, this study was designed to assess in the genetically traceable in vivo model Caenorhabditis elegans the role of PARylation as well as the consequences of loss of pme-1 or pme-2 (orthologues of PARP1 and PARP2) in Mn-induced toxicity. METHODS: A specific and sensitive isotope-dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to quantify PARylation in worms. Next to monitoring the PAR level, pme-1 and pme-2 gene expression as well as Mn-induced oxidative stress was studied in wildtype worms and the pme deletion mutants. RESULTS AND CONCLUSION: While Mn failed to induce PARylation in wildtype worms, toxic doses of Mn led to PAR-induction in pme-1-deficient worms, due to an increased gene expression of pme-2 in the pme-1 deletion mutants. However, this effect could not be observed at sub-toxic Mn doses as well as upon longer incubation times. Regarding Mn-induced oxidative stress, the deletion mutants did not show hypersensitivity. Taken together, this study characterizes worms to model PAR inhibition and addresses the consequences for Mn-induced oxidative stress in genetically manipulated worms.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/enzimologia , Manganês/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Animais , Cromatografia Líquida , Glutationa/metabolismo , Espectrometria de Massas em Tandem
12.
Cortex ; 117: 168-181, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30981955

RESUMO

Neuroimaging and transcranial magnetic stimulation (TMS) studies have implicated a dorsal fronto-parietal network in endogenous attention control and a more ventral set of areas in exogenous attention shifts. However, the extent and circumstances under which these cortical networks overlap and/or interact remain unclear. Crucially, whereas previous studies employed experimental designs that tend to confound exogenous with endogenous attentional engagement, we used a cued target discrimination paradigm that behaviourally dissociates exogenous from endogenous attention processes. Participants engaged with endogenous attention cues, while simultaneous apparent motion cues were driving exogenous attention along the motion path towards or away from the target position. To interfere with dorsal or ventral attention networks, we delivered neuronavigated double-pulse TMS over either right intraparietal sulcus (rIPS) or right temporo-parietal junction (rTPJ) towards the end of the cue target interval, and compared the effects to a sham-TMS condition. For sham-TMS, endogenous and exogenous cueing both benefitted discrimination accuracy. Target discrimination was enhanced at validly versus invalidly cued locations (endogenous cueing benefit) as well as when targets appeared in versus out of the motion path (exogenous cueing benefit), despite motion being uninformative and task-irrelevant, replicating previous findings. Interestingly, both rIPS- and rTPJ-TMS abolished attention benefits from exogenous cueing, while endogenous cueing benefits were unaffected. Our findings provide evidence against independent involvement of the dorsal and ventral attention network nodes in exogenous attention processes.


Assuntos
Antecipação Psicológica/fisiologia , Atenção/fisiologia , Encéfalo/fisiologia , Rede Nervosa/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico , Sinais (Psicologia) , Feminino , Humanos , Masculino , Vias Neurais/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia , Estimulação Magnética Transcraniana , Adulto Jovem
13.
PLoS One ; 10(12): e0144082, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26623650

RESUMO

Many behaviourally relevant sensory events such as motion stimuli and speech have an intrinsic spatio-temporal structure. This will engage intentional and most likely unintentional (automatic) prediction mechanisms enhancing the perception of upcoming stimuli in the event stream. Here we sought to probe the anticipatory processes that are automatically driven by rhythmic input streams in terms of their spatial and temporal components. To this end, we employed an apparent visual motion paradigm testing the effects of pre-target motion on lateralized visual target discrimination. The motion stimuli either moved towards or away from peripheral target positions (valid vs. invalid spatial motion cueing) at a rhythmic or arrhythmic pace (valid vs. invalid temporal motion cueing). Crucially, we emphasized automatic motion-induced anticipatory processes by rendering the motion stimuli non-predictive of upcoming target position (by design) and task-irrelevant (by instruction), and by creating instead endogenous (orthogonal) expectations using symbolic cueing. Our data revealed that the apparent motion cues automatically engaged both spatial and temporal anticipatory processes, but that these processes were dissociated. We further found evidence for lateralisation of anticipatory temporal but not spatial processes. This indicates that distinct mechanisms may drive automatic spatial and temporal extrapolation of upcoming events from rhythmic event streams. This contrasts with previous findings that instead suggest an interaction between spatial and temporal attention processes when endogenously driven. Our results further highlight the need for isolating intentional from unintentional processes for better understanding the various anticipatory mechanisms engaged in processing behaviourally relevant stimuli with predictable spatio-temporal structure such as motion and speech.


Assuntos
Atenção/fisiologia , Orientação/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Percepção Visual/fisiologia , Adulto , Sinais (Psicologia) , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Movimento (Física) , Estimulação Luminosa/métodos , Percepção Espacial/fisiologia , Adulto Jovem
14.
Front Neurosci ; 8: 228, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25126055

RESUMO

There is not only evidence for behavioral differences in voice perception between female and male listeners, but also recent suggestions for differences in neural correlates between genders. The fMRI functional voice localizer (comprising a univariate analysis contrasting stimulation with vocal vs. non-vocal sounds) is known to give robust estimates of the temporal voice areas (TVAs). However, there is growing interest in employing multivariate analysis approaches to fMRI data (e.g., multivariate pattern analysis; MVPA). The aim of the current study was to localize voice-related areas in both female and male listeners and to investigate whether brain maps may differ depending on the gender of the listener. After a univariate analysis, a random effects analysis was performed on female (n = 149) and male (n = 123) listeners and contrasts between them were computed. In addition, MVPA with a whole-brain searchlight approach was implemented and classification maps were entered into a second-level permutation based random effects models using statistical non-parametric mapping (SnPM; Nichols and Holmes, 2002). Gender differences were found only in the MVPA. Identified regions were located in the middle part of the middle temporal gyrus (bilateral) and the middle superior temporal gyrus (right hemisphere). Our results suggest differences in classifier performance between genders in response to the voice localizer with higher classification accuracy from local BOLD signal patterns in several temporal-lobe regions in female listeners.

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