Publications by authors named "Ivan Ruiz"

Background: Genetic testing for neurodevelopmental disorders is now considered the standard of care for unexplained epilepsy as well as autism spectrum disorders, intellectual disability, and developmental delays with as many as 50% of individuals identified as having an underlying genetic etiology. Capicua () is a transcriptional repressor and is widely expressed among human brain tissue. Patients in the literature with pathogenic variants in present with a broad spectrum of phenotypic abnormalities.

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  • The study investigates whether anhedonia in individuals with schizophrenia (SZ) is due to emotional memory impairment for positive experiences instead of a reduced ability to feel pleasure.
  • The research involved 30 SZ participants and 30 healthy controls who completed an eye-tracking task to measure how they remembered pleasant, unpleasant, and neutral stimuli, assessing their emotional responses during and after viewing.
  • Results showed that both groups initially processed emotional stimuli similarly, but SZ participants showed worse recognition for pleasant items over time, indicating a specific issue with remembering positive experiences linked to higher anhedonia severity.
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Animals constantly integrate sensory information with prior experience to select behavioral responses appropriate to the current situation. Genetic factors supporting this behavioral flexibility are often disrupted in neuropsychiatric conditions, such as the autism-linked gene which supports acoustically evoked habituation learning. encodes an AP2 endocytosis adaptor complex subunit, although its behavioral mechanisms and importance have been unclear.

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  • * A study compared SZ outpatients and healthy controls (CN) using a cognitive effort allocation task (COGED), revealing that SZ participants were less willing to work for rewards and showed less flexibility in their effort choices under varying cognitive demands.
  • * Those with SZ who held strong defeatist beliefs about their performance were particularly reluctant to choose high-effort tasks when faced with increased cognitive load, indicating that addressing these beliefs could help improve decision-making in this population.
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Negative symptoms are a strong predictor of functional impairment in schizophrenia (SZ). Unfortunately, mechanisms underlying negative symptoms are poorly understood and available treatments are minimally effective. The current study evaluated the novel hypothesis that negative symptoms are associated with an implicit cognitive effort monitoring impairment that manifests during tasks requiring sustained allocation of cognitive control.

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Codon usage bias has long been appreciated to influence protein production. Yet, relatively few studies have analyzed the impacts of codon usage on tissue-specific mRNA and protein expression. Here, we use codon-modified reporters to perform an organism-wide screen in for distinct tissue responses to codon usage bias.

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Negative symptoms are core features of schizophrenia-spectrum disorders that are frequently observed across all phases of illness. By their nature, COVID-19 social isolation, physical distancing, and health precautions induce behavioural aspects of negative symptoms. However, it is unclear whether these prevention measures also lead to increases in experiential negative symptoms, whether such effects are equivalent across individual negative symptom domains, and if exacerbations occur equivalently across phases of illness.

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Psychotic disorders are characterized by a generalized neurocognitive deficit (i.e., performance 1.

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Objective: Recent conceptual frameworks propose anhedonia reflects abnormalities in the temporal dynamics of positive emotion in schizophrenia, characterized by intact consummatory and impaired anticipatory pleasure. A comprehensive meta-analysis can directly test this theory using self-report data.

Method: A meta-analysis was performed on studies reporting Temporal Experience of Pleasure Scale (TEPS) data from healthy controls and schizophrenia or schizotypy groups.

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Rocky Mountain spotted fever (RMSF) has been reported in Colombia since 1937. Most recent outbreaks were in 2006-2008, followed by the absence of recognized cases. This report describes new clinical cases of RMSF and epidemiologic investigations.

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Background: The majority of small-scale gold miners worldwide, including those in Mozambique, use mercury to extract gold. Over the last fifty years, gold production from small-scale mining has been accelerating and consequently the amount of mercury released to the environment has increased dramatically, causing major global health problems. In 2018, a team from the Danish non-governmental organization Diálogos introduced the mercury-free gold extraction method in the Cabo Delgado province in Mozambique in the villages of Waqueia and Nanlia.

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Prior studies using exploratory factor analysis provide evidence that negative symptoms are best conceptualized as 2 dimensions reflecting diminished motivation and expression. However, the 2-dimensional model has yet to be evaluated using more complex mathematical techniques capable of testing structure. In the current study, network analysis was applied to evaluate the latent structure of negative symptoms using a community-detection algorithm.

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Background: Individuals with schizophrenia have deficits in social cognition that are associated with poor functional outcome. Unfortunately, current treatments result in only modest improvement in social cognition. Oxytocin, a neuropeptide with pro-social effects, has significant benefits for social cognition in the general population.

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Hedonic response is preserved in schizophrenia. However, it is unclear whether this is also true in individuals meeting criteria for "prodromal" psychosis, who are considered to be at symptomatic high risk for developing the disorder. In this study, we examined neurophysiological and self-reported response to emotional stimuli in UHR ( = 23) and healthy control (CN:  = 30) participants who passively viewed pleasant, unpleasant, and neutral images for 500 ms while the electroencephalogram was recorded and then provided self-reports of valence and arousal to the stimuli.

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The present work introduces the use of environmental sensors to assess indoor air quality (IAQ) in combination with human biometrics. The sensor array included temperature, relative humidity, carbon dioxide, and noise monitors. The array was used in a classroom as well as in a vehicle cabin to assess the carbon dioxide production rate of individuals in a closed ventilation environment.

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Background: The hypothesis that defeatist performance attitudes are associated with decreased goal-directed task effort and negative symptoms in consumers with schizophrenia was investigated by using pupillary responses as a biomarker of task effort. Pupillary dilation during cognitive tasks provides a biomarker of effort devoted to the task, with greater dilation indicating greater effort.

Methods: Defeatist attitudes were assessed in 149 consumers with schizophrenia or schizoaffective disorder and 50 healthy control subjects, and consumers were divided into three groups (tertile split) with respect to severity of defeatist attitudes.

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Objective: The aim of this study was to investigate the relationship between age and cannabis use in patients with a first psychotic episode, and to analyze the mediating effect of comorbid use of other drugs and sex on age at onset of psychosis.

Method: All consenting patients (aged 15 to 65 years) with a first psychotic episode needing inpatient psychiatric treatment during a 2-year period between February 1997 and January 1999 were considered, confirming a total of 131 patients. Subjects were interviewed using the Structured Clinical Interview for DSM-IV Axis I Disorders, and clinical and demographic data were collected.

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Objective: Evaluate the clinical and functional behavior of the ventricular and atrioventricular stimulation modes in the elective replacement of pulse generator in patients with chagasic cardiopathy and atrioventricular block.

Methods: Twenty-seven patients under ventricular and atrioventricular stimulation were comparatively evaluated at the beginning of the study, and alternately in ventricular and atrioventricular modes in two 90-day phases, with regard to: the clinical behavior evaluated according to quality of life and functional class, and the functional behavior evaluated by transthoracic echocardiography and the six-minute walk test. The statistical analysis was performed with patients at baseline, and under ventricular and atrioventricular modes, using the chi-square test and the repeated measures analysis of variance, and taking into consideration a 0.

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A new case of MURCS association (mullerian duct aplasia, renal aplasia and cervicothoracic somite dysplasia) in an 18 year old patient is reported. In addition to other minor phenotypical features, hypothalamic chronic anovulation was documented. Basal concentrations of PRL, TSH, GH, F and E were within reference values for adult women.

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