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1.
Artículo en Inglés | MEDLINE | ID: mdl-38904702

RESUMEN

BACKGROUND: Klinefelter syndrome (KS), also referred to as XXY syndrome, is a significant but inadequately studied risk factor for neuropsychiatric disability. Whether alterations in functional brain connectivity or pubertal delays are associated with aberrant cognitive-behavioral outcomes in individuals with KS is largely unknown. In this observational study, we investigated KS-related alterations in the resting-state brain network, testosterone level, and cognitive-behavioral impairment in adolescents with Klinefelter syndrome. METHODS: We recruited 46 boys with KS, ages 8 to 17 years, and 51 age-matched typically developing (TD) boys. All participants underwent resting-state functional magnetic resonance imaging scans, pubertal, and cognitive-behavioral assessments. Resting-state functional connectivity and regional brain activity of the participants were assessed. RESULTS: We found widespread alterations in global functional connectivity among the inferior frontal gyrus, temporal-parietal area, and hippocampus in boys with KS. Aberrant regional activities, including enhanced fALFF in the motor area and reduced ReHo in the caudate, were also found in the KS group compared to the TD children. Further, using machine learning methods, brain network alterations in these regions accurately differentiated boys with KS from TD controls. Finally, we showed that the alterations of brain network properties not only effectively predict cognitive-behavioral impairment in boys with KS, but also appear to mediate the association between total testosterone level and language ability, a cognitive domain at particular risk for dysfunction in this condition. CONCLUSION: Our results offer an informatic neurobiological foundation for understanding cognitive-behavioral impairments in individuals with KS and contribute to our understanding of the interplay between pubertal status, brain function, and cognitive-behavioral outcome in this population.

2.
Mol Psychiatry ; 27(9): 3768-3776, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35595977

RESUMEN

Girls with fragile X syndrome (FXS) often manifest significant symptoms of avoidance, anxiety, and arousal, particularly in the context of social interaction. However, little is currently known about the associations among neurobiological, biobehavioral such as eye gaze pattern, and social-cognitive dysfunction in real-world settings. In this study, we sought to characterize brain network properties and eye gaze patterns in girls with FXS during natural social interaction. Participants included 42 girls with FXS and 31 age- and verbal IQ-matched girls (control). Portable functional near-infrared spectroscopy (fNIRS) and an eye gaze tracker were used to investigate brain network alterations and eye gaze patterns associated with social-cognitive dysfunction in girls with FXS during a structured face-to-face conversation. Compared to controls, girls with FXS showed significantly increased inter-regional functional connectivity and greater excitability within the prefrontal cortex (PFC), frontal eye field (FEF) and superior temporal gyrus (STG) during the conversation. Girls with FXS showed significantly less eye contact with their conversational partner and more unregulated eye gaze behavior compared to the control group. We also demonstrated that a machine learning approach based on multimodal data, including brain network properties and eye gaze patterns, was predictive of multiple domains of social-cognitive behaviors in girls with FXS. Our findings expand current knowledge of neural mechanisms and eye gaze behaviors underlying naturalistic social interaction in girls with FXS. These results could be further evaluated and developed as intermediate phenotypic endpoints for treatment trial evaluation in girls with FXS.


Asunto(s)
Síndrome del Cromosoma X Frágil , Femenino , Humanos , Fijación Ocular , Interacción Social , Encéfalo , Cognición
3.
Horm Behav ; 149: 105300, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36640638

RESUMEN

Turner syndrome (TS), a common neurogenetic disorder caused by complete or partial absence of an X chromosome in females, is characterized by distinct physical, cognitive, and social-emotional features. Girls with TS typically display average overall intellectual functioning with relative strength in verbal abilities and weaknesses in visuospatial processing, executive function (EF), and social cognition. This study was designed to better understand longitudinal trajectories of cognitive and social-emotional domains commonly affected in TS. Participants included 57 girls with monosomic 45,X TS and 55 age- and verbal-IQ matched girls who completed behavioral, child-report, and parent-report measures across four timepoints. Group differences in visuospatial processing, EF, social cognition, and anxiety were assessed longitudinally. Potential effects of estrogen replacement therapy (ERT) were assessed cross-sectionally on an exploratory basis. The TS group showed poorer performance on measures of visuospatial processing, EF, and social cognition, but not anxiety, compared to controls throughout childhood and adolescence. There were no significant group differences in the trajectory of skill development over time. Exploratory analyses within the TS group revealed that girls who were receiving ERT showed better performance on measures of overall IQ, expressive vocabulary, and visuospatial processing compared to those not receiving ERT. Consistent with existing literature, weaknesses in visuospatial processing, EF, and social competence among girls with TS persisted throughout childhood and adolescence. Exploratory analyses suggest that ERT may help improve some aspects of cognitive function in TS, although other pre-existing, nonhormonal differences between the two TS subgroups may alternatively explain these findings, given our study design. Future studies are needed to examine potential impacts of ERT on cognitive and social-emotional development in TS.


Asunto(s)
Cognición Social , Síndrome de Turner , Femenino , Humanos , Adolescente , Niño , Habilidades Sociales , Síndrome de Turner/genética , Síndrome de Turner/psicología , Cognición , Función Ejecutiva
4.
Dev Psychopathol ; : 1-12, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37185087

RESUMEN

Children with fragile X syndrome (FXS) often avoid eye contact, a behavior that is potentially related to hyperarousal. Prior studies, however, have focused on between-person associations rather than coupling of within-person changes in gaze behaviors and arousal. In addition, there is debate about whether prompts to maintain eye contact are beneficial for individuals with FXS. In a study of young females (ages 6-16), we used eye tracking to assess gaze behavior and pupil dilation during social interactions in a group with FXS (n = 32) and a developmentally similar comparison group (n = 23). Participants engaged in semi-structured conversations with a female examiner during blocks with and without verbal prompts to maintain eye contact. We identified a social-behavioral and psychophysiological profile that is specific to females with FXS; this group exhibited lower mean levels of eye contact, significantly increased mean pupil dilation during conversations that included prompts to maintain eye contact, and showed stronger positive coupling between eye contact and pupil dilation. Our findings strengthen support for the perspective that gaze aversion in FXS reflects negative reinforcement of social avoidance behavior. We also found that behavioral skills training may improve eye contact, but maintaining eye contact appears to be physiologically taxing for females with FXS.

5.
J Pediatr Psychol ; 47(1): 25-36, 2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-34718672

RESUMEN

OBJECTIVE: Children and adolescents, who have less developed coping skills, are affected by natural disasters and other traumatic events differently than adults. Emotional and behavioral effects are particularly pronounced during a pandemic-related disaster, when support networks that typically promote healthy coping, such as friends, teachers, and family members, may be less available. Children and adolescents with fragile X syndrome (FXS), who are at increased risk for developing anxiety and depression, may be particularly vulnerable to behavioral or emotional difficulties during a pandemic. This study examined the mental health outcomes of school-aged girls with FXS during the COVID-19 pandemic and associated stay-at-home orders. METHODS: Participants included 47 school-aged girls with FXS and 33 age- and developmentally matched comparison girls. Associations between COVID-19 behavioral and emotional outcomes and prior academic, adaptive, behavioral, and emotional functioning as well as prior maternal mental health and characteristics of the mother-child relationship were examined. Qualitative data from the parental report of emotional and behavioral responses to the pandemic were also obtained. RESULTS: Results indicate that school-aged girls with FXS demonstrate a distinct profile of COVID-19 related associations compared to the comparison group, such that pandemic-related worries and emotional impact of pandemic restrictions were predicted by prior mental health factors for the comparison group but by prior social, behavioral, and relational factors for the FXS group. CONCLUSIONS: Findings provide insight into factors that may confer risk or resilience for youth with special needs, suggesting potential therapeutic targets and informing public health initiatives in response to the pandemic.


Asunto(s)
COVID-19 , Síndrome del Cromosoma X Frágil , Adolescente , Adulto , Niño , Femenino , Síndrome del Cromosoma X Frágil/epidemiología , Humanos , Salud Mental , Pandemias , SARS-CoV-2
6.
J Dev Behav Pediatr ; 44(7): e476-e485, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37696031

RESUMEN

OBJECTIVE: Klinefelter syndrome (KS; 47, XXY), the most common sex chromosome aneuploidy in males, is characterized by testicular failure and testosterone deficiency as well as a variety of cognitive, social, and emotional challenges. In the current study, we aimed to clarify the cognitive-behavioral profile of peripubertal boys with KS using measures of cognition, academic achievement, adaptive behavior, and quality of life. METHOD: We compared 47 boys with KS (7-16 years of age) with 55 performance IQ-matched boys without KS on measures of cognition (WISC-V), executive function (BRIEF-2), academic achievement (KTEA-3), adaptive behavior (Vineland-3), and quality of life (PROMIS). In exploratory analyses, we examined associations among these measures and potential associations with pubertal metrics. RESULTS: Boys with KS demonstrated a significantly different profile of cognition, behavioral ratings of executive function, academic achievement, adaptive behavior, and quality of life compared with their typically developing peers, with, on average, lower functioning. The groups showed significantly different correlations between cognition and aspects of quality of life. No associations were observed between behavior and pubertal development. CONCLUSION: Taken together, these findings indicated that boys with KS are at increased risk for cognitive difficulties, which may affect academic achievement, adaptive behavior, and quality of life. Although initial exploratory analyses indicated that the magnitude of these alterations was not correlated with severity of testicular failure, longitudinal analyses currently being conducted by our group may help clarify the trajectory of these difficulties through the pubertal transition and testosterone replacement.


Asunto(s)
Éxito Académico , Síndrome de Klinefelter , Masculino , Adolescente , Niño , Humanos , Calidad de Vida , Cognición , Adaptación Psicológica , Testosterona
7.
Res Dev Disabil ; 143: 104622, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37939495

RESUMEN

BACKGROUND: Fragile X syndrome (FXS) is the leading monogenic cause of intellectual disability and autism in males and females. Females with FXS typically display a milder cognitive phenotype than males, despite experiencing significant developmental, behavioral, and social-emotional issues. AIMS: To measure and distinguish the cognitive-behavioral profile of girls with FXS relative to verbal IQ-matched peers. METHODS AND PROCEDURES: Ninety-seven participants (NFXS=55, Ncomparison=42) six to 16 years of age completed assessments evaluating cognition, academic achievement, and adaptive behavior. The comparison group consisted of age-, sex-, and verbal IQ-matched peers. OUTCOMES AND RESULTS: Consistent with previous studies, the FXS group demonstrated mean cognitive skills, academic achievement, and adaptive behavior in the borderline to low average range. On average, the FXS group showed poorer nonverbal reasoning, visual pattern recognition, verbal abstraction, math abilities, attention, inhibitory control, and working memory than the comparison group. There were no significant group differences in adaptive behavior. Different patterns of associations between cognition and selected outcomes emerged in each group. CONCLUSIONS AND IMPLICATIONS: Results highlight the importance of identifying specific cognitive-behavioral profiles in girls with FXS to inform more targeted interventions for optimizing outcomes and quality of life in this population.


Asunto(s)
Éxito Académico , Síndrome del Cromosoma X Frágil , Masculino , Femenino , Humanos , Niño , Síndrome del Cromosoma X Frágil/psicología , Calidad de Vida , Cognición , Adaptación Psicológica
8.
Artículo en Inglés | MEDLINE | ID: mdl-34555563

RESUMEN

BACKGROUND: Children and adolescents with fragile X syndrome (FXS) manifest significant symptoms of anxiety, particularly in response to face-to-face social interaction. In this study, we used functional near-infrared spectroscopy to reveal a specific pattern of brain activation and habituation in response to face stimuli in young girls with FXS, an important but understudied clinical population. METHODS: Participants were 32 girls with FXS (age: 11.8 ± 2.9 years) and a control group of 28 girls without FXS (age: 10.5 ± 2.3 years) matched for age, general cognitive function, and autism symptoms. Functional near-infrared spectroscopy was used to assess brain activation during a face habituation task including repeated upright/inverted faces and greeble (nonface) objects. RESULTS: Compared with the control group, girls with FXS showed significant hyperactivation in the frontopolar and dorsal lateral prefrontal cortices in response to all face stimuli (upright + inverted). Lack of neural habituation (and significant sensitization) was also observed in the FXS group in the frontopolar cortex in response to upright face stimuli. Finally, aberrant frontopolar sensitization in response to upright faces in girls with FXS was significantly correlated with notable cognitive-behavioral and social-emotional outcomes relevant to this condition, including executive function, autism symptoms, depression, and anxiety. CONCLUSIONS: These findings strongly support a hypothesis of neural hyperactivation and accentuated sensitization during face processing in FXS, a phenomenon that could be developed as a biomarker end point for improving treatment trial evaluation in girls with this condition.


Asunto(s)
Reconocimiento Facial , Síndrome del Cromosoma X Frágil , Niño , Femenino , Adolescente , Humanos , Síndrome del Cromosoma X Frágil/psicología , Encéfalo , Corteza Cerebral , Biomarcadores
9.
J Dev Behav Pediatr ; 43(9): e565-e572, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36219483

RESUMEN

OBJECTIVE: Female patients with fragile X syndrome (FXS), a genetic condition associated with a mutation in the FMR1 gene, are at significantly elevated risk for developing anxiety and depression. This study is designed to better understand these symptoms in school-age girls, particularly as they relate to age, social skills, and functional outcomes. METHODS: We compared 58 girls aged 6 to 16 years with FXS with 46 age-matched, sex-matched, and developmentally matched peers without FXS on measures of anxiety, depression, social skills, adaptive behavior, and quality of life. RESULTS: Girls with FXS 10.5 years and older demonstrated significantly higher levels of depression, withdrawal, and social avoidance than girls younger than 10.5 years with FXS ( p -values < 0.01). Girls in the comparison group did not show any age-related differences on these measures. The older FXS cohort also showed associations between social communication and interaction skills, adaptive behavior, and measures of anxiety and depression ( p -values < 0.05) not seen in the comparison group, regardless of age. CONCLUSION: We found that age seems to play an important role in the development of mood symptoms and that such symptoms are uniquely correlated with social communication and reciprocal social interaction behaviors and adaptive functioning in girls with FXS after puberty. These data suggest a critical window of intervention for girls with FXS in the improvement of social interaction skills and the prevention of social avoidance and symptoms of anxiety and depression, with the ultimate goal of improving quality of life and promoting greater independence.


Asunto(s)
Ansiedad , Depresión , Síndrome del Cromosoma X Frágil , Habilidades Sociales , Femenino , Humanos , Ansiedad/epidemiología , Depresión/epidemiología , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil , Síndrome del Cromosoma X Frágil/epidemiología , Calidad de Vida , Niño , Adolescente
10.
Front Microbiol ; 13: 829378, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35185850

RESUMEN

Shotgun metagenomics studies have improved our understanding of microbial population dynamics and have revealed significant contributions of microbes to gut homeostasis. They also allow in silico inference of the metagenome. While they link the microbiome with metabolic abnormalities associated with disease phenotypes, they do not capture microbial gene expression patterns that occur in response to the multitude of stimuli that constantly ambush the gut environment. Metatranscriptomics closes that gap, but its implementation is more expensive and tedious. We assessed the metabolic perturbations associated with gut inflammation using shotgun metagenomics and metatranscriptomics. Shotgun metagenomics detected changes in abundance of bacterial taxa known to be SCFA producers, which favors gut homeostasis. Bacteria in the phylum Firmicutes were found at decreased abundance, while those in phyla Bacteroidetes and Proteobacteria were found at increased abundance. Surprisingly, inferring the coding capacity of the microbiome from shotgun metagenomics data did not result in any statistically significant difference, suggesting functional redundancy in the microbiome or poor resolution of shotgun metagenomics data to profile bacterial pathways, especially when sequencing is not very deep. Obviously, the ability of metatranscriptomics libraries to detect transcripts expressed at basal (or simply low) levels is also dependent on sequencing depth. Nevertheless, metatranscriptomics informed about contrasting roles of bacteria during inflammation. Functions involved in nutrient transport, immune suppression and regulation of tissue damage were dramatically upregulated, perhaps contributed by homeostasis-promoting bacteria. Functions ostensibly increasing bacteria pathogenesis were also found upregulated, perhaps as a consequence of increased abundance of Proteobacteria. Bacterial protein synthesis appeared downregulated. In summary, shotgun metagenomics was useful to profile bacterial population composition and taxa relative abundance, but did not inform about differential gene content associated with inflammation. Metatranscriptomics was more robust for capturing bacterial metabolism in real time. Although both approaches are complementary, it is often not possible to apply them in parallel. We hope our data will help researchers to decide which approach is more appropriate for the study of different aspects of the microbiome.

11.
Sci Rep ; 11(1): 13053, 2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-34158543

RESUMEN

Detection of low abundance target DNA/RNA for clinical or research purposes is challenging because the target sequences can be hidden under a large background of human genomic or non-human metagenomic sequences. We describe a probe-based capture method to enrich for target sequences with DNA-clicked iron oxide nanoparticles. Our method was tested against commercial capture assays using streptavidin beads, on a set of probes derived from a common genotype of the hepatitis C virus. We showed that our method is more specific and sensitive, most likely due to the combination of an inert silica coating and a high density of DNA probes clicked to the nanoparticles. This facilitates target capture below the limits of detection for TaqMan qPCR, and we believe that this method has the potential to transform management of infectious diseases.


Asunto(s)
Química Clic , ADN/análisis , Nanopartículas Magnéticas de Óxido de Hierro/química , Oligonucleótidos/química , ARN/análisis , Genoma Viral , Hepacivirus/genética , Hepatitis/sangre , Hepatitis/virología , Humanos , Estreptavidina/química
12.
Cell Rep Med ; 2(10): 100404, 2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34755126

RESUMEN

Pathological examination is the gold standard for cancer diagnosis, and breast tumor cells are often found in clusters. We report a case study on one triple-negative breast cancer (TNBC) patient, analyzing tumor development, metastasis, and prognosis with simultaneous DNA and RNA sequencing of pathologist-defined cell clusters from multiregional frozen sections. The cell clusters are isolated by laser capture microdissection (LCM) from primary tumor tissue, lymphatic vessels, and axillary lymph nodes. Data are reported for a total of 97 cell clusters. A combination of tumor cell-cluster clonality and phylogeny reveals 3 evolutionarily distinct pathways for this patient, each associated with a unique mRNA signature, and each correlated with disparate survival outcomes. Hub gene analysis indicates that extensive downregulation of ribosomal protein mRNA is a potential marker of poor prognosis in breast cancer.


Asunto(s)
Linaje de la Célula/genética , ADN de Neoplasias/genética , Genoma Humano , ARN Neoplásico/genética , Neoplasias de la Mama Triple Negativas/diagnóstico , Neoplasias de la Mama Triple Negativas/genética , Agregación Celular/genética , Células Clonales , ADN de Neoplasias/metabolismo , Progresión de la Enfermedad , Células Epiteliales/clasificación , Células Epiteliales/metabolismo , Células Epiteliales/patología , Resultado Fatal , Femenino , Regulación Neoplásica de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Metástasis Linfática , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patología , Linfocitos/clasificación , Linfocitos/metabolismo , Linfocitos/patología , Filogenia , Pronóstico , ARN Neoplásico/metabolismo , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Adulto Joven
13.
Inflamm Bowel Dis ; 21(6): 1419-27, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25939040

RESUMEN

Inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis, are poorly understood disorders affecting the intestinal tract. The current model for disease suggests that genetically susceptible patients develop intolerance to gut microflora, and chronic inflammation develops as a result of environmental insults. Although interest has mainly focused on studying genetic variants and gut bacterial flora, little is known about the potential of viral infection to contribute to disease. Accordingly, we conducted a metagenomic analysis to document the baseline virome in colonic biopsy samples from patients with IBD in order to assess the contribution of viral infection to IBD. Libraries were generated from colon RNA to create approximately 2 GB sequence data per library. Using a bioinformatic pipeline designed to detect viral sequences, more than 1000 viral reads were derived directly from tissue without any coculture or isolation procedure. Herein, we describe the complexity and abundance of viruses, bacteria/bacteriophage, and human endogenous retroviral sequences from 10 patients with IBD and 5 healthy subjects undergoing surveillance colonoscopy. Differences in gut microflora and the abundance of mammalian viruses and human endogenous retroviruses were readily detected in the metagenomic analyses. Specifically, patients with herpesviridae sequences in their colon demonstrated increased expression of human endogenous viral sequences and differences in the diversity of their microbiome. This study provides a promising metagenomic approach to describe the colonic microbiome that can be used to better understand virus-host and phage-bacteria interactions in IBD.


Asunto(s)
Colon/microbiología , Microbioma Gastrointestinal/genética , Enfermedades Inflamatorias del Intestino/microbiología , Metagenómica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacteriófagos , Niño , Colonoscopía , Femenino , Herpesviridae/genética , Humanos , Masculino , Persona de Mediana Edad , ARN Viral , Proteínas de los Retroviridae/genética , Adulto Joven
14.
PLoS One ; 8(4): e60595, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23613733

RESUMEN

We conducted an unbiased metagenomics survey using plasma from patients with chronic hepatitis B, chronic hepatitis C, autoimmune hepatitis (AIH), non-alcoholic steatohepatitis (NASH), and patients without liver disease (control). RNA and DNA libraries were sequenced from plasma filtrates enriched in viral particles to catalog virus populations. Hepatitis viruses were readily detected at high coverage in patients with chronic viral hepatitis B and C, but only a limited number of sequences resembling other viruses were found. The exception was a library from a patient diagnosed with hepatitis C virus (HCV) infection that contained multiple sequences matching GB virus C (GBV-C). Abundant GBV-C reads were also found in plasma from patients with AIH, whereas Torque teno virus (TTV) was found at high frequency in samples from patients with AIH and NASH. After taxonomic classification of sequences by BLASTn, a substantial fraction in each library, ranging from 35% to 76%, remained unclassified. These unknown sequences were assembled into scaffolds along with virus, phage and endogenous retrovirus sequences and then analyzed by BLASTx against the non-redundant protein database. Nearly the full genome of a heretofore-unknown circovirus was assembled and many scaffolds that encoded proteins with similarity to plant, insect and mammalian viruses. The presence of this novel circovirus was confirmed by PCR. BLASTx also identified many polypeptides resembling nucleo-cytoplasmic large DNA viruses (NCLDV) proteins. We re-evaluated these alignments with a profile hidden Markov method, HHblits, and observed inconsistencies in the target proteins reported by the different algorithms. This suggests that sequence alignments are insufficient to identify NCLDV proteins, especially when these alignments are only to small portions of the target protein. Nevertheless, we have now established a reliable protocol for the identification of viruses in plasma that can also be adapted to other patient samples such as urine, bile, saliva and other body fluids.


Asunto(s)
ADN Viral/sangre , Técnicas y Procedimientos Diagnósticos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Hígado/virología , ARN Viral/sangre , Tropismo Viral/genética , Virus/genética , Secuencia de Bases , Biología Computacional , ADN Viral/genética , Biblioteca de Genes , Genoma Viral/genética , Humanos , Hígado/patología , ARN Viral/genética , Proteínas Virales/genética
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