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1.
J Pers Med ; 14(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38929814

RESUMEN

Current United States Preventive Services Task Force (USPSTF) recommendations include routine screening for breast, cervical, colorectal, and lung cancer; however, two out of every three cancer cases occur in other indications, leading to diagnoses in advanced stages of the disease and a higher likelihood of mortality. Blood-based multi-cancer early detection (MCED) tests can impact cancer screening and early detection by monitoring for multiple different cancer types at once, including indications where screening is not performed routinely today. We conducted a survey amongst healthcare providers (HCPs), payers, and patients within the U.S. health system to understand the current utilization of cancer screening tests and the anticipated barriers to widespread adoption of blood-based MCED tests. The results indicated that the community favors the adoption of blood-based MCED tests and that there is broad agreement on the value proposition. Despite this recognition, the survey highlighted that there is limited use today due to the perceived lack of clinical accuracy and utility data, high out-of-pocket patient costs, and lack of payer coverage. To overcome the hurdles for future widespread adoption of blood-based MCED tests, increased investment in data generation, education, and implementation of logistical support for HCPs will be critical.

2.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38731851

RESUMEN

COVID-19 is characterized by a wide range of clinical manifestations, where aging, underlying diseases, and genetic background are related to worse outcomes. In the present study, the differential expression of seven genes related to immunity, IRF9, CCL5, IFI6, TGFB1, IL1B, OAS1, and TFRC, was analyzed in individuals with COVID-19 diagnoses of different disease severities. Two-step RT-qPCR was performed to determine the relative gene expression in whole-blood samples from 160 individuals. The expression of OAS1 (p < 0.05) and IFI6 (p < 0.05) was higher in moderate hospitalized cases than in severe ones. Increased gene expression of OAS1 (OR = 0.64, CI = 0.52-0.79; p = 0.001), IRF9 (OR = 0.581, CI = 0.43-0.79; p = 0.001), and IFI6 (OR = 0.544, CI = 0.39-0.69; p < 0.001) was associated with a lower risk of requiring IMV. Moreover, TGFB1 (OR = 0.646, CI = 0.50-0.83; p = 0.001), CCL5 (OR = 0.57, CI = 0.39-0.83; p = 0.003), IRF9 (OR = 0.80, CI = 0.653-0.979; p = 0.03), and IFI6 (OR = 0.827, CI = 0.69-0.991; p = 0.039) expression was associated with patient survival. In conclusion, the relevance of OAS1, IRF9, and IFI6 in controlling the viral infection was confirmed.


Asunto(s)
2',5'-Oligoadenilato Sintetasa , COVID-19 , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón , SARS-CoV-2 , Humanos , 2',5'-Oligoadenilato Sintetasa/genética , COVID-19/genética , COVID-19/inmunología , COVID-19/virología , Masculino , Femenino , Persona de Mediana Edad , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/genética , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Proteínas Nucleares/genética , Adulto , Anciano , Proteínas Mitocondriales
3.
Plants (Basel) ; 13(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38611445

RESUMEN

One of the phytopathogens that cause severe damage to jalapeño pepper is Leveillula taurica (Lév.) Arnaud, the causative agent of powdery mildew. Synthetic fungicides are currently employed for its control, contributing to adverse effects on human health and the environment. The main objective of this research was to identify the causal agent of powdery mildew and assess the efficacy of chitosan in powdery mildew control on jalapeño pepper. The following treatments were evaluated in laboratory and greenhouse conditions: T1 = 0.0125% chitosan, T2 = 0.0025% chitosan, T3 = 0.05% chitosan, T4 = 0.1% chitosan, T5 = 0.2% chitosan, T6 = tebuconazole 25% (1.8 mL/L water), and T7 = control (water). Symptomatology results indicated that L. taurica is indeed the causative agent of powdery mildew. Treatments T4 and T5 exhibited the lowest percentages of incidences and severity, hence achieving higher control efficacy in the laboratory (57.70 ± 3.85 and 65.39 ± 3.85) and greenhouse (56.67 ± 4.08 and 70 ± 8.16%) compared to T6 (control efficacy, 38.46 ± 0.00% in the laboratory and 50 ± 0.00% in the greenhouse). The chitosan derived from shrimp had a significant impact on the cell walls of L. taurica spores and mycelium. Consequently, chitosan emerges as a viable organic alternative to fungicides for controlling powdery mildew in jalapeño pepper.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38661631

RESUMEN

Our theory of positively reinforced free-operant behavior (Perez & Dickinson, 2020) assumes that responding is controlled by two systems. One system is sensitive to the correlation between response and reinforcement rates and controls goal-directed behavior, whereas a habitual system learns by reward prediction error. We present an extension of this theory to the aversive domain that explains why free-operant avoidance responding increases with both the experienced rate of negative reinforcement and the difference between this rate and that programmed by the avoidance schedule. The theory also assumes that the habitual component is reinforced by the acquisition of aversive inhibitory properties by the feedback stimuli generated by responding, which then act as safety signals that reinforce habit performance. Our analysis suggests that the distinction between habitual and goal-directed control of rewarded behavior can also be applied to the aversive domain. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

5.
Phys Chem Chem Phys ; 26(6): 5621-5632, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38288508

RESUMEN

In this work we performed a detailed numerical analysis to investigate the static and dynamic magnetic properties of hexagonal cells of square and circular cobalt nanodots as a function of the distance between them and the external magnetic field to which they are subjected. By simulating hysteresis curves with the external magnetic field applied parallel and perpendicular to the plane of these nanostructures, we can conclude that the cobalt nanodots presented a significant perpendicular magnetic anisotropy. We also obtained that the coercivity increases with decreasing volume, which implies that the circular dots have a higher coercivity than the square dots. Furthermore, we studied the dynamic susceptibility of these systems and found that it is possible to control both the position and the number of resonance peaks by controlling the geometry and the distance between the magnetic nanodots. This work provides useful information on the behaviour of cobalt nanodot arrays, opening paths for the design and improvement of two-dimensional technological devices.

6.
Neurobiol Learn Mem ; 204: 107794, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37473985

RESUMEN

The influence of the Rescorla-Wagner model cannot be overestimated, despite that (1) the model does not differ much computationally from its predecessors and competitors, and (2) its shortcomings are well-known in the learning community. Here we discuss the reasons behind its widespread influence in the cognitive and neural sciences, and argue that it is the constant search for general-process theories by learning scholars which eventually produced a model whose application spans many different areas of research to this day. We focus on the theoretical and empirical background of the model, the theoretical connections that it has with later developments across Marr's levels of analysis, as well as the broad variety of research that it has guided and inspired.


Asunto(s)
Aprendizaje por Asociación , Condicionamiento Clásico , Aprendizaje
7.
Front Cell Infect Microbiol ; 13: 1173213, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37389217

RESUMEN

COVID-19 is characterized by a wide range of symptoms where the genetic background plays a key role in SARS-CoV-2 infection. In this study, the relative expression of IRF9, CCL5, IFI6, TGFB1, IL1B, OAS1, and TFRC genes (related to immunity and antiviral activity) was analyzed in upper airway samples from 127 individuals (97 COVID-19 positive and 30 controls) by using a two-step RT-PCR. All genes excepting IL1B (p=0.878) showed a significantly higher expression (p<0.005) in COVID-19 cases than in the samples from the control group suggesting that in asymptomatic-mild cases antiviral and immune system cells recruitment gene expression is being promoted. Moreover, IFI6 (p=0.002) and OAS1 (p=0.044) were upregulated in cases with high viral loads, which could be related to protection against severe forms of this viral infection. In addition, a higher frequency (68.7%) of individuals infected with the Omicron variant presented higher viral load values of infection when compared to individuals infected with other variants (p<0.001). Furthermore, an increased expression of IRF9 (p<0.001), IFI6 (p<0.001), OAS1 (p=0.011), CCL5, (p=0.003) and TGFB1 (p<0.001) genes was observed in individuals infected with SARS-CoV-2 wildtype virus, which might be due to immune response evasion of the viral variants and/or vaccination. The obtained results indicate a protective role of IFI6, OAS1 and IRF9 in asymptomatic -mild cases of SARS-CoV-2 infection while the role of TGFB1 and CCL5 in the pathogenesis of the disease is still unclear. The importance of studying the dysregulation of immune genes in relation to the infective variant is stand out in this study.


Asunto(s)
COVID-19 , Humanos , COVID-19/genética , Antivirales , SARS-CoV-2/genética , Evasión Inmune
8.
Melanoma Res ; 33(5): 375-387, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37307530

RESUMEN

Melanoma is one of the most common cancers in the world. The main routes of tumor progression are related to angiogenesis and lymphangiogenesis. These routes can occur by local invasion, which is called angiolymphatic invasion (ALI). In this study, we assess gene expression of relevant biomarkers of angiogenesis and lymphangiogenesis in 80 FFPE melanoma samples to determine a molecular profile that correlates with ALI, tumor progression, and disease-free survival. The results were enhanced by a posttranscriptional analysis by an immunofluorescence assay. Three SNPs in the VEGFR-2 gene were genotyped in 237 malignant melanoma (MM) blood DNA samples by qPCR. A significant correlation was found for LYVE -1 and ALI, qualitative ( P  = 0.017) and quantitative ( P  = 0.005). An increased expression of protein LIVE-1 in ALI samples supported these results ( P  = 0.032). VEGFR2 was lower in patients who showed disease progression ( P  = 0.005) and protein VEGFR2 posttranscriptional expression decreased ( P  = 0.016). DFS curves showed differences ( P  = 0.023) for VEGFR2 expression detected versus the absence of VEGFR2 expression. No significant influence on DFS was detected for the remaining analyzed genes. Cox regression analysis suggested that VEGFR2 expression has a protective role (HR = 0.728; 95% CI = 0.552-0.962; P  = 0.025) on disease progression. No significant association was found between any of the studied SNPs of VEGFR2 and DFS or progression rate. Our main results suggest that LYVE-1 gene expression is closely related to ALI; the relationship with the development of metastases in MM deserves further studies. Low expression of VEGFR2 was associated with disease progression and the expression of VEGFR2 correlates with an increased DFS.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/genética , Supervivencia sin Enfermedad , Linfangiogénesis/genética , Progresión de la Enfermedad , Melanoma Cutáneo Maligno
9.
Podium (Pinar Río) ; 18(1)abr. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1440756

RESUMEN

El proyecto "Estudio de patrones de lateralidad de atletas elites de Cuba" tiene como objetivo el diagnóstico, la caracterización y la valoración de los patrones de lateralidad de atletas activos y retirados con altos resultados deportivos, pero hasta el momento se adolece de una profundización en la utilidad que puede tener la lateralidad en la preparación técnico-táctica en los deportes de combate, por lo que el objetivo de este artículo fue sistematizar las principales investigaciones relacionadas con la utilización de la lateralidad en estos deportes. Para ello, se emplearon los métodos inductivo-deductivo, análisis-síntesis y revisión bibliográfica con el fin de determinar los antecedentes e interpretar las principales investigaciones referentes sobre esta temática. Se concluyó que entre los principales aspectos abordados estuvieron: las ventajas competitivas de los deportistas zurdos, el volumen técnico que se realizó en competiciones, la caracterización del deportista de acuerdo a sus preferencias laterales y cómo estas influyen en el rendimiento deportivo. Sin embargo, no se apreció estudio alguno referido a la utilización de los patrones de la lateralidad en la preparación técnico-táctica en los deportes de combate, lo que devino en carencia, para el estudio de estas disciplinas deportivas.


O projeto "Estudo dos padrões de lateralidade de atletas de elite em Cuba" tem como objetivo diagnosticar, caracterizar e avaliar os padrões de lateralidade de atletas ativos e aposentados com altos resultados esportivos, mas até agora não houve um estudo aprofundado da utilidade que a lateralidade pode ter na preparação técnico-táctica em esportes de combate, portanto o objetivo deste artigo foi sistematizar as principais pesquisas relacionadas com o uso da lateralidade nestes esportes. Para este fim, foram utilizados os métodos indutivo-deducativo, análise-síntese e revisão bibliográfica a fim de determinar os antecedentes e interpretar as principais pesquisas sobre este assunto. Concluiu-se que entre os principais aspectos abordados estavam: as vantagens competitivas dos atletas canhotos, o volume técnico realizado nas competições, a caracterização do atleta de acordo com suas preferências laterais e como estas influenciam o desempenho esportivo. Entretanto, não foi encontrado nenhum estudo sobre o uso de padrões de lateralidade na preparação técnico-táctica em esportes de combate, o que resultou em uma falta de estudo destas disciplinas esportivas.


The project "Study of laterality patterns of elite athletes in Cuba" has as its objective the diagnosis, characterization and assessment of laterality patterns of active and retired athletes with high sports results, but so far it lacks a deepening in the usefulness that laterality can have in the technical-tactical preparation in combat sports, so the objective of this article was to systematize the main researches related to the use of laterality in these sports. For this, the inductive-deductive, analysis-synthesis and bibliographic review methods were used in order to determine the background and interpret the main reference research on this subject. It was concluded that among the main aspects addressed were: the competitive advantages of left-handed athletes, the technical volume that was carried out in competitions, the characterization of the athlete according to their lateral preferences and how they influence sports performance. However, no study was observed regarding the use of laterality patterns in technical-tactical preparation in combat sports, which became a lack, for the study of these sports disciplines.

10.
Microorganisms ; 11(3)2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36985159

RESUMEN

Fungi of the family Botryosphaeriaceae are considered responsible for various symptoms in avocado such as dieback, external necrosis of branches and inflorescences, cankers on branches and trunks, or stem-end rot of fruits. In recent years, these problems are becoming more frequent in avocado orchards in the Canary Islands (Spain). This work includes the characterization of fungal species involved in these diseases, which were isolated from avocado crops in Tenerife Island between 2018 and 2022. A total of 158 vegetal samples were collected, from which 297 fungal isolates were culture-isolated. Fifty-two of them were selected according to their morphological features as representative isolates of Botryosphaeriaceae, and their molecular characterization was carried out, sequencing the ITS1-2 region as well as the ß-tubulin and the elongation factor 1-alpha genes. Five species of Botryosphaeriaceae were isolated, including Neofusicoccum australe, N. cryptoaustrale/stellenboschiana, N. luteum, N. parvum, and Lasiodiplodia brasiliensis. This is the first time that L. brasiliensis has been associated with avocado dieback and that N. cryptoaustrale/stellenboschiana has been cited in avocado causing symptoms of dieback and stem-end rot. However, it was not possible to assign our isolates unequivocally to N. cryptoaustrale or N. stellenboschiana even additionally using the rpb2 marker for their molecular characterization. Botryosphaeriaceae family seem to be involved in avocado dieback, in the premature fall of fruits during their development in the field and in post-harvest damage in Tenerife, but further studies are needed to clarify the fungal pathogens associated with symptoms in relation to phenological plant growth stages or less frequently observed.

12.
Int J Mol Sci ; 25(1)2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38203550

RESUMEN

Cutaneous squamous cell carcinoma (CSCC) is one of the most common cancers in the skin. CSCC belongs to the non-melanoma skin cancers, and its incidence is increasing every year around the world. The principal routes of tumor progression are related to angiogenesis and lymphangiogenesis. In this study, we assess the gene expression of the relevant biomarkers of both routes in 49 formalin-fixed paraffin-embedded (FFPE) CSCC samples in an attempt to determine a molecular profile that correlates with the tumor progression and disease-free survival (DFS). The results were enhanced by a posttranscriptional analysis using an immunofluorescence assay. Overexpression of the vascular endothelial growth factor C (VEGFC) gene was found in patients with tumor progression (p = 0.022) and in patients with perineural invasion (p = 0.030). An increased expression of protein VEGFC in samples with tumor progression supported these results (p = 0.050). In addition, DFS curves showed differences (p = 0.027) for tumors with absent-low VEGFC expression versus those with high levels of VEGFC expression. No significant influence on DFS was detected for the remaining analyzed genes. VEGFC expression was found to be a risk factor in the disease progression (HR = 2.675; 95% CI: 1.089-6.570; p = 0.032). Our main results suggest that VEGFC gene expression is closely related to tumor progression, DFS, and the presence of perineural invasion.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Cutáneas , Humanos , Carcinoma de Células Escamosas/genética , Supervivencia sin Enfermedad , Expresión Génica , Neoplasias Cutáneas/genética , Factor C de Crecimiento Endotelial Vascular/genética
13.
Behav Brain Sci ; 45: e265, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36353862

RESUMEN

Understanding how culture evolves in society is an extremely difficult task. The bifocal stance theory (BST) deploys two copying strategies which can be linked to dual-system theories of behavior. BST would benefit from incorporating results from these theories, such as the evolution of attention to goals or steps of a behavioral sequence, and the role of the environment in prompting different copying strategies.


Asunto(s)
Hábitos , Humanos
14.
PLoS Comput Biol ; 18(9): e1010410, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36084131

RESUMEN

In the natural world, stimulus-outcome associations are often ambiguous, and most associations are highly complex and situation-dependent. Learning to disambiguate these complex associations to identify which specific outcomes will occur in which situations is critical for survival. Pavlovian occasion setters are stimuli that determine whether other stimuli will result in a specific outcome. Occasion setting is a well-established phenomenon, but very little investigation has been conducted on how occasion setters are disambiguated when they themselves are ambiguous (i.e., when they do not consistently signal whether another stimulus will be reinforced). In two preregistered studies, we investigated the role of higher-order Pavlovian occasion setting in humans. We developed and tested the first computational model predicting direct associative learning, traditional occasion setting (i.e., 1st-order occasion setting), and 2nd-order occasion setting. This model operationalizes stimulus ambiguity as a mechanism to engage in higher-order Pavlovian learning. Both behavioral and computational modeling results suggest that 2nd-order occasion setting was learned, as evidenced by lack and presence of transfer of occasion setting properties when expected and the superior fit of our 2nd-order occasion setting model compared to the 1st-order occasion setting or direct associations models. These results provide a controlled investigation into highly complex associative learning and may ultimately lead to improvements in the treatment of Pavlovian-based mental health disorders (e.g., anxiety disorders, substance use).


Asunto(s)
Aprendizaje por Asociación , Aprendizaje Discriminativo , Condicionamiento Clásico , Señales (Psicología) , Humanos , Aprendizaje
15.
J Pers Med ; 12(7)2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35887521

RESUMEN

Despite evidence that precision medicine (PM) results in improved patient care, the broad adoption and implementation has been challenging across the United States (US). To better understand the perceived barriers associated with PM adoption, a quantitative survey was conducted across five stakeholders including medical oncologists, surgeons, lab directors, payers, and patients. The results of the survey reveal that stakeholders are often not aligned on the perceived challenges with PM awareness, education and reimbursement, with there being stark contrast in viewpoints particularly between clinicians, payers, and patients. The output of this study aims to help raise the awareness that misalignment on the challenges to PM adoption is contributing to broader lack of implementation that ultimately impacts patients. With better understanding of stakeholder viewpoints, we can help alleviate the challenges by focusing on multi-disciplinary education and awareness to ultimately improve patient outcomes.

16.
Artículo en Inglés | MEDLINE | ID: mdl-35886529

RESUMEN

(1) Background: Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) continues to cause profound health, economic, and social problems worldwide. The management and disinfection of materials used daily in health centers and common working environments have prompted concerns about the control of coronavirus disease 2019 (COVID-19) infection risk. Ozone is a powerful oxidizing agent that has been widely used in disinfection processes for decades. The aim of this study was to assess the optimal conditions of ozone treatment for the elimination of heat-inactivated SARS-CoV-2 from office supplies (personal computer monitors, keyboards, and computer mice) and clinical equipment (continuous positive airway pressure tubes and personal protective equipment) that are difficult to clean. (2) Methods: The office supplies and clinical equipment were contaminated in an area of 1 cm2 with 1 × 104 viral units of a heat-inactivated SARS-CoV-2 strain, then treated with ozone using two different ozone devices: a specifically designed ozonation chamber (for low-medium ozone concentrations over large volumes) and a clinical ozone generator (for high ozone concentrations over small volumes). SARS-CoV-2 gene detection was carried out using quantitative real-time polymerase chain reaction (RT-qPCR). (3) Results: At high ozone concentrations over small surfaces, the ozone eliminated SARS-CoV-2 RNA in short time periods-i.e., 10 min (at 4000 ppm) or less. The optimum ozone concentration over large volumes was 90 ppm for 120 min in ambient conditions (24 °C and 60-75% relative humidity). (4) Conclusions: This study showed that the appropriate ozone concentration and exposure time eliminated heat-inactivated SARS-CoV-2 RNA from the surfaces of different widely used clinical and office supplies, decreasing their risk of transmission, and improving their reutilization. Ozone may provide an additional tool to control the spread of the COVID-19 pandemic.


Asunto(s)
COVID-19 , Ozono , COVID-19/prevención & control , Humanos , Pandemias/prevención & control , ARN Viral , SARS-CoV-2
17.
PLoS One ; 17(7): e0271826, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35867641

RESUMEN

The current COVID-19 pandemic is causing profound health, economic, and social problems worldwide. The global shortage of medical and personal protective equipment (PPE) in specialized centers during the outbreak demonstrated the need for efficient methods to disinfect and recycle them in times of emergency. We have previously described that high ozone concentrations destroyed viral RNA in an inactivated SARS-CoV-2 strain within a few minutes. However, the efficient ozone dosages for active SARS-CoV-2 are still unknown. The present study aimed to evaluate the systematic effects of ozone exposure on face masks from hospitalized patients infected with SARS-CoV-2. Face masks from COVID-19 patients were collected and treated with a clinical ozone generator at high ozone concentrations in small volumes for short periods. The study focused on SARS-CoV-2 gene detection (assessed by real-time quantitative polymerase chain reaction (RT-qPCR)) and on the virus inactivation by in vitro studies. We assessed the effects of different high ozone concentrations and exposure times on decontamination efficiency. We showed that high ozone concentrations (10,000, 2,000, and 4,000 ppm) and short exposure times (10, 10, and 2 minutes, respectively), inactivated both the original strain and the B.1.1.7 strain of SARS-CoV-2 from 24 contaminated face masks from COVID-19 patients. The validation results showed that the best condition for SARS-CoV-2 inactivation was a treatment of 4,000 ppm of ozone for 2 minutes. Further studies are in progress to advance the potential applications of these findings.


Asunto(s)
COVID-19 , Ozono , COVID-19/prevención & control , Humanos , Máscaras , Ozono/farmacología , Ozono/uso terapéutico , Pandemias/prevención & control , SARS-CoV-2
18.
Learn Mem ; 29(7): 160-170, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35710303

RESUMEN

Theories of learning distinguish between elemental and configural stimulus processing depending on whether stimuli are processed independently or as whole configurations. Evidence for elemental processing comes from findings of summation in animals where a compound of two dissimilar stimuli is deemed to be more predictive than each stimulus alone, whereas configural processing is supported by experiments using similar stimuli in which summation is not found. However, in humans the summation effect is robust and impervious to similarity manipulations. In three experiments in human predictive learning, we show that summation can be obliterated when partially reinforced cues are added to the summands in training and tests. This lack of summation only holds when the partially reinforced cues are similar to the reinforced cues (experiment 1) and seems to depend on participants sampling only the most salient cue in each trial (experiments 2a and 2b) in a sequential visual search process. Instead of attributing our and others' instances of lack of summation to the customary idea of configural processing, we offer a formal subsampling rule that might be applied to situations in which the stimuli are hard to parse from each other.


Asunto(s)
Aprendizaje por Asociación , Señales (Psicología) , Animales , Condicionamiento Clásico , Humanos
19.
Learn Mem ; 29(1): 16-28, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34911800

RESUMEN

It has been suggested that there are two distinct and parallel mechanisms for controlling instrumental behavior in mammals: goal-directed actions and habits. To gain an understanding of how these two systems interact to control behavior, it is essential to characterize the mechanisms by which the balance between these systems is influenced by experience. Studies in rodents have shown that the amount of training governs the relative expression of these two systems: Behavior is goal-directed following moderate training, but the more extensively an instrumental action is trained, the more it becomes habitual. It is less clear whether humans exhibit similar training effects on the expression of goal-directed and habitual behavior, as human studies have reported contradictory findings. To tackle these contradictory findings, we formed a consortium, where four laboratories undertook a preregistered experimental induction of habits by manipulating the amount of training. There was no statistical evidence for a main effect of the amount of training on the formation and expression of habits. However, exploratory analyses suggest a moderating effect of the affective component of stress on the impact of training over habit expression. Participants who were lower in affective stress appeared to be initially goal-directed, but became habitual with increased training, whereas participants who were high in affective stress were already habitual even after moderate training, thereby manifesting insensitivity to overtraining effects. Our findings highlight the importance of the role of moderating variables such as individual differences in stress and anxiety when studying the experimental induction of habits in humans.


Asunto(s)
Condicionamiento Operante , Objetivos , Animales , Hábitos , Humanos , Motivación
20.
Curr Issues Mol Biol ; 43(3): 2167-2176, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34940125

RESUMEN

Formalin-fixed paraffin-embedded (FFPE) tumour samples may provide crucial data regarding biomarkers for neoplasm progression. Analysis of gene expression is frequently used for this purpose. Therefore, mRNA expression needs to be normalized through comparison to reference genes. In this study, we establish which of the usually reported reference genes is the most reliable one in cutaneous malignant melanoma (MM) and cutaneous squamous cell carcinoma (CSCC). ACTB, TFRC, HPRT1 and TBP expression was quantified in 123 FFPE samples (74 MM and 49 CSCC biopsies) using qPCR. Expression stability was analysed by NormFinder and Bestkeeper softwares, and the direct comparison method between means and SD. The in-silico analysis with BestKeeper indicated that HPRT1 was more stable than ACTB and TFRC in MM (1.85 vs. 2.15) and CSCC tissues (2.09 vs. 2.33). The best option to NormFinder was ACTB gene (0.56) in MM and TFRC (0.26) in CSCC. The direct comparison method showed lower SD means of ACTB expression in MM (1.17) and TFRC expression in CSCC samples (1.00). When analysing the combination of two reference genes for improving stability, NormFinder indicated HPRT1 and ACTB to be the best for MM samples, and HPRT1 and TFRC genes for CSCC. In conclusion, HPRT1 and ACTB genes in combination are the most appropriate choice for normalization in gene expression studies in MM FFPE tissue, while the combination of HPRT1 and TFRC genes are the best option in analysing CSCC FFPE samples. These may be used consistently in forthcoming studies on gene expression in both tumours.


Asunto(s)
Biomarcadores de Tumor , Expresión Génica , Histocitoquímica , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Anciano , Anciano de 80 o más Años , Biología Computacional , Femenino , Perfilación de la Expresión Génica/métodos , Histocitoquímica/métodos , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Adhesión en Parafina , Reacción en Cadena en Tiempo Real de la Polimerasa , Neoplasias Cutáneas/patología , Fijación del Tejido
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