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1.
Psychol Serv ; 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38127500

RESUMEN

Coordinated specialty care (CSC) is the dominant model for early psychosis care in the United States, representing a proactive recovery-oriented approach to serious mental illness in its early stages. CSC involves broad multidisciplinary support for participants, including from psychologists in some CSC teams, encompassing educational and vocational support, medication management, psychotherapy, case management, peer support, and family interventions. CSC programs have proliferated in the last 20 years, leading to a quality-access dialectic, where increasing access to treatment simultaneously prompts concerns about care quality, particularly in the context of staffing shortages and funding limits. Evidence-based psychosocial treatment, including psychotherapy, is an integral part of CSC, yet workforce training deficits, workforce turnover, and CSC financing pose threats to intervention fidelity and thus CSC participants' ability to access high-quality care. We propose an enhanced role for psychologists as a way of resolving the quality-access dialectic in the area of psychosocial treatment, specifically evidence-based therapy. We describe the potential of psychologists' skills in clinical supervision, formulation, evidence-based interventions and measurement-based care, drawing on practice examples. After considering possible limitations, we outline implementation models, for example, drawing on Early Psychosis Intervention Network and Project Extension for Community Healthcare Outcomes. We conclude with four recommendations: Psychologists should be placed in CSC team or network-leadership roles; psychological expertise should be made available to CSC teams for training, consultation, and technical assistance; psychological expertise should be used to address CSC implementation challenges; and research is needed to demonstrate psychologists' value to stakeholders. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

2.
Child Youth Serv Rev ; 1552023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37982096

RESUMEN

Sexual minority youth have long remained an understudied population within the juvenile justice system, despite emerging evidence suggesting that sexual minority youth are overrepresented. Recent literature indicates that system-involved sexual minority youth may have more behavioral health concerns than their heterosexual counterparts. Even so, more work is needed to elucidate the unique needs of sexual minority youth who become involved in the system, especially as it pertains to suicidal behaviors and non-suicidal self-injury (NSSI). The present study provided a descriptive evaluation of the prevalence of sexual minority youth making early system contact and their mental health concerns. Of the 218 justice-involved youth from a Northeastern family court in the sample, over a quarter identified as a sexual minority (n = 58). Our findings indicated that these youth evidenced significantly higher scores on a mental health screener compared to their heterosexual counterparts, evidencing greater symptomology on scales indicative of depression/anxiety, thought disturbance, etc. Further, sexual minority youth reported higher rates of lifetime, past year, and past month NSSI as well as lifetime and past year suicide attempts. These findings highlight the need to support the well-being of sexual minority youth in the juvenile justice system by screening for and addressing their mental health needs in this unique setting.

3.
Schizophr Bull ; 49(6): 1486-1493, 2023 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-37621256

RESUMEN

BACKGROUND: Paranoid beliefs commonly occur in the general adolescent population. Exposure to adverse life events (ALEs) and/or bullying are important environmental risk factors. The extent to which others, especially parents, are available to help a young person cope with stressful situations may offset this risk. STUDY DESIGN: A cross-sectional adolescent-parent dyad design (n = 142 pairs) was used to test whether an adolescent's perception of being supported by their family, and/or the parent's perception of stress and burden in their parenting role, moderated the association between environmental risk and adolescent paranoid beliefs. STUDY RESULTS: Moderation analysis indicated that ALEs were significantly associated with adolescent paranoid beliefs when parents reported high stress and burden in their parenting role. Conversely, at low and moderate levels of parental stress, ALEs were unrelated to paranoid beliefs. Bullying was strongly associated with paranoia, with no moderation effects. The adolescent's perception of support within their family had no moderating effects. CONCLUSIONS: Findings indicate that the focus of prevention should be shifted beyond just families of adolescents who are experiencing psychosis and/or have high "at-risk" profiles, to families of adolescents exposed to ALEs. Targeted support for parents to help reduce parental stress and burden, and help foster protective family environments even in the face of ALEs, is an important avenue for reducing the risk of paranoid beliefs in adolescents. Further research is required to better understand how to offset the deleterious effect of bullying on paranoid beliefs in adolescents.


Asunto(s)
Acoso Escolar , Trastornos Paranoides , Humanos , Adolescente , Trastornos Paranoides/etiología , Responsabilidad Parental , Apoyo Familiar , Estudios Transversales , Padres , Relaciones Padres-Hijo
4.
J College Stud Psychother ; 36(2): 201-222, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35694629

RESUMEN

Evidence supports the use of brief psychosis-spectrum screening tools for identifying individuals at an increased risk of developing a psychotic disorder. Screening has not been well studied in general mental health settings that serve young adults in the age range associated with highest risk for psychosis. This study explored the feasibility of psychosis-risk screening and assessment among help-seeking students at a university counseling center. The PRIME Screen-Revised was administered to students at clinic intake. Participants who screened positively were offered a follow-up assessment using the Structured Interview for Psychosis-risk Syndromes (SIPS). At intake, 510 students completed the PRIME Screen-Revised, with 132 (25.9%) screening positive. Comprehensive psychosis-spectrum evaluations were completed with 38 participants, and 22 met criteria for a psychosis-spectrum disorder, representing 57.9% of this subsample. Findings suggest that psychosis-risk screening in a college clinic is a promising approach to identifying those at high risk for or in the early stages of psychosis.

5.
R I Med J (2013) ; 105(4): 26-30, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35476732

RESUMEN

Individuals with psychosis-spectrum conditions have strikingly high rates of suicidal thoughts and behaviors, especially in the early stages of illness. Given increasing rates of suicide among adolescents, and given that psychosis symptoms often emerge during this developmental period, it is important that practitioners working with adolescents are attuned to the intersection of psychotic experiences and suicide risk. Furthermore, youth with emerging signs of psychosis often struggle with other mental health concerns that are linked to suicidal thoughts and behaviors, including depression, anxiety, mania, trauma, and substance use. Taken together, these factors indicate that identifying early signs of psychosis can be critical for addressing suicide risk, and psychosis-spectrum symptoms are important experiences to include in safety planning for youth. Herein we discuss considerations for safety planning for adolescents experiencing psychosis-spectrum symptoms, drawn from clinical observations and pilot data collected from adolescents in a psychiatric inpatient unit and their families.


Asunto(s)
Trastornos Psicóticos , Trastornos Relacionados con Sustancias , Prevención del Suicidio , Suicidio , Adolescente , Ansiedad , Humanos , Ideación Suicida , Suicidio/psicología
6.
Child Youth Care Forum ; 51(3): 579-592, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34305371

RESUMEN

Background: Given reports of the adverse effects of COVID-19 on adolescent mental health, it is critical to understand how it impacts psychiatrically hospitalized youth who may be particularly vulnerable to its effects. Objective: This study aimed to advance our understanding of high-risk adolescents' experiences of COVID-19, including COVID-19-related stress, changes in daily functioning, and coping as they relate to suicidal ideation (SI). Method: Participants were 107 youth (ages 11-18; M = 15.06, SD = 1.79) admitted to an adolescent psychiatric inpatient unit during the time when the initial COVID-19 safety measures (i.e., school closure, stay-at-home- order) and reopening initiatives (Phase I, II, and III) were implemented in Rhode Island between March 13th and July 19th 2020. Adolescents completed measures of COVID-19-related stress, coping, functioning, and SI at the time of admission. Results: Nearly half of the sample (43%) reported a negative impact of COVID-19 on daily functioning. Youth who endorsed COVID-19-related decline in functioning evidenced higher levels of SI compared to youth with no change or improvement in functioning due to COVID-19. Overall levels of stress were not associated with SI. Greater coping repertoire, but not the use of specific coping strategies was associated with higher levels of SI. Conclusions: Findings demonstrate the importance of examining COVID-19-related changes in functioning and broadening repertoire of coping strategies among adolescents at high risk for SI. Supplementary Information: The online version contains supplementary material available at 10.1007/s10566-021-09641-1.

7.
Psychiatry Res ; 307: 114322, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34922238

RESUMEN

Evidence supports the use of brief psychosis-spectrum screening measures to identify individuals at elevated risk for psychosis, however, there is limited research on psychosis-spectrum screening among adolescents hospitalized for acute mental health concerns. Given the psychiatric vulnerability of this population, screening efforts within inpatient settings may help identify adolescents at greatest risk for ongoing mental health concerns including psychosis. This study investigates the use of two brief screening tools to identify psychosis-spectrum symptoms in psychiatrically hospitalized adolescents. Upon intake, adolescents completed two screening measures, the PRIME Screen-Revised and the Youth Self-Report Thought Problems scale, followed by a brief interview to evaluate psychosis-spectrum diagnoses. Associations between screening scores and diagnostic status were explored to evaluate the use of these tools to identify psychosis-spectrum conditions in this population. The sample included 57 adolescents, 28 of whom met psychosis-spectrum criteria. Psychosis-spectrum status was strongly correlated with PRIME scores (r = 0.59) and Thought Problems T scores (r = 0.55). Logistic regression analyses indicated that both screening measures demonstrate promising accuracy (74-81%) for identifying adolescents meeting psychosis-spectrum criteria. The PRIME and Thought Problems scale may be appropriate screening tools for use in adolescent inpatient settings to identify those experiencing clinically significant psychosis-spectrum symptoms.


Asunto(s)
Pacientes Internos , Trastornos Psicóticos , Adolescente , Humanos , Tamizaje Masivo , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/psicología , Autoinforme
8.
Clin Psychol Rev ; 87: 102038, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34034038

RESUMEN

Despite considerable public and scholarly debate about the role of social media in self-injurious thoughts and behaviors (SITBs), no comprehensive, quantitative synthesis of this literature has previously been undertaken. The current systematic review and meta-analysis examines associations between social media use and SITBs, including suicidal ideation, suicide plans, suicide attempts, and nonsuicidal self-injury (NSSI). A range of social media behaviors and experiences were identified, including cybervictimization and perpetration, exposure to and generation of SITB-related content, problematic use, sexting, social media importance, and frequency of use. A systematic search of PsycINFO, Medline, CINAHL, and the references of prior reviews yielded 61 eligible studies. Results largely suggested medium effect sizes for associations between specific social media constructs (cybervictimization, SITB-related social media use, problematic social media use) and SITBs. There was no association between frequency of social media use and SITBs; however, studies on this topic were limited. The majority of studies identified focused on cybervictimization, and results suggested positive associations with all SITBs, with the association between cybervictimization and suicidal ideation stronger for adolescents than adults. Overall, findings highlight the utility of examining specific social media behaviors and experiences, and point to the need for more research in this area.


Asunto(s)
Conducta Autodestructiva , Medios de Comunicación Sociales , Adolescente , Adulto , Humanos , Factores de Riesgo , Ideación Suicida , Intento de Suicidio
9.
J Affect Disord Rep ; 4: 100100, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33558865

RESUMEN

BACKGROUND: Psychiatrically vulnerable adolescents may be at heightened risk for suicide during the COVID-19 pandemic. This study characterizes suicidal ideation (SI) and suicide attempts (SA) in a sample of adolescents psychiatrically hospitalized during COVID-19. Rates of SI and SA are compared to a historical hospital sample from a matched period in the year prior. Associations between specific stressors and COVID-related SI are also explored. METHODS: This cross-sectional chart review utilizes hospital intake data, including self-reports of SA, SI (general and COVID-related), and COVID-specific stressors. RESULTS: SA and SI ratings were higher in the COVID-19 sample compared to the historical sample. Stressors related to missing special events, financial problems, in-home conflict, and changes in living circumstances were associated with COVID-related SI. Among first-time admissions, several interpersonal stressors were linked to COVID-related SI. LIMITATIONS: Analyses were cross-sectional, limiting our ability to draw conclusions about causality. CONCLUSIONS: This study offers preliminary evidence that COVID-19 may be contributing to suicidal thoughts and behaviors in high-risk adolescents.

10.
Psychiatry Res ; 296: 113668, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33401091

RESUMEN

Suicide is a leading cause of death for young adults, and college-enrolled students are at markedly high risk for suicide. Psychotic-like experiences (PLEs) and sleep difficulties are prevalent among college students and have been linked to increased suicidal ideation (SI). This cross-sectional study examined the relation between PLEs and SI, moderated by sleep quality, in a sample of 442 students at a university counseling center. The Behavioral Health Measure-43 (BHM-43) was used to evaluate mental health symptoms, including sleep quality and SI. The PRIME Screen-Revised was used to measure PLEs. Regression results indicated that higher PRIME scores statistically predicted greater SI. There was a significant interaction between PRIME and sleep quality in predicting SI. Among individuals with greater sleep difficulties, PLEs were positively, significantly associated with SI. The PRIME was not a significant predictor of SI at lower levels of sleep difficulties (i.e. better sleep quality). This interaction effect remained significant when controlling for age and the BHM-43 depression and bipolar subscales. Findings suggest that sleep difficulties may be linked to increased SI for individuals with PLEs, and better sleep may be protective. Further research is needed to explore treatment targeting PLEs and/or sleep to mitigate suicide risk among university students.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Estudiantes/psicología , Ideación Suicida , Adolescente , Adulto , Consejo , Estudios Transversales , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Trastornos Psicóticos , Sueño , Suicidio , Encuestas y Cuestionarios , Universidades , Adulto Joven
11.
Early Interv Psychiatry ; 15(4): 949-956, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-32954685

RESUMEN

AIM: Early psychosocial treatment for psychosis-spectrum symptoms has been linked to positive outcomes, whereas delayed treatment is associated with poorer prognosis. Thus, there is a critical need to bolster psychotherapy engagement efforts, particularly among high-risk groups and during high-risk periods, in order to maximize recovery. This study explores the relation between psychosis-spectrum symptoms and psychotherapy readiness among psychiatrically hospitalized adolescents, a foundational step for developing more effective psychotherapy engagement approaches for this population. METHODS: Adolescents (n = 704; 12-18 years) who were admitted to a psychiatric inpatient unit completed the Readiness for Psychotherapy Index (RPI), a psychosis-spectrum questionnaire (PRIME Screen), and a brief diagnostic interview at intake. Correlational patterns and regression analyses were used to explore associations between variables. RESULTS: The PRIME Screen was negatively associated with the RPI Openness subscale and positively associated with the Distress subscale, beyond the effects of demographics (ie, age, sex, race) and psychiatric diagnoses. CONCLUSIONS: Results indicate that the RPI probes multiple facets of psychotherapy readiness that have unique associations with psychosis-spectrum experiences. Adolescents with higher PRIME scores endorsed greater mental health-related distress and lower levels of openness to psychotherapy. These psychotherapy readiness factors warrant further exploration, as they may be significant barriers or facilitators to engaging adolescents with psychosis-spectrum symptoms in much needed early treatment services.


Asunto(s)
Adolescente Hospitalizado , Trastornos Psicóticos , Adolescente , Hospitalización , Humanos , Psicoterapia , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/terapia , Encuestas y Cuestionarios
12.
Early Interv Psychiatry ; 15(2): 406-411, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32436366

RESUMEN

AIM: Evidence supports the use of brief psychosis-spectrum screeners for identifying individuals at risk for psychosis. Screening has not been well-studied in help-seeking college samples. This study investigated the use of the Behavior Assessment System for Children, Second Edition (BASC-2) Atypicality Scale as a psychosis-spectrum screening tool within a university counselling centre. METHODS: Atypicality scores from the BASC-2 were compared to interview-based assessment, the Structured Interview for Psychosis-risk Syndromes (SIPS), to explore associations across the measures and evaluate the scale's ability to identify individuals who meet criteria for a psychosis-spectrum diagnosis. RESULTS: Forty-three participants completed the BASC-2 and SIPS, and 23 were SIPS-positive. Compared to the SIPS-negative group, the SIPS-positive group had significantly higher Atypicality scores. Exploratory results indicated that Atypicality scores identified SIPS-positive individuals with an overall accuracy of 72% (78% sensitivity, 65% specificity). CONCLUSION: The Atypicality Scale may be an appropriate first-line psychosis-spectrum screening tool in college counselling centres.


Asunto(s)
Trastornos Psicóticos , Universidades , Niño , Consejo , Humanos , Síntomas Prodrómicos , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/diagnóstico
13.
J Psychiatr Res ; 130: 327-332, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32877826

RESUMEN

OBJECTIVE: Rates of self-injurious thoughts and behaviors have increased in adolescents over the past two decades. Sexual and gender minority (SGM) youth report elevated rates of self-injurious thoughts and behaviors compared to heterosexual and cisgender youth. Studies of factors influencing suicide risk in SGM youth remain limited, however, and have largely been conducted in community or epidemiological samples. METHOD: The present study aimed to address these limitations by examining the prevalence and clinical characteristics of sexual and gender minority youth in a sample of 515 youth admitted to an adolescent inpatient unit. In addition, the present study aimed to compare rates of self-reported self-injurious thoughts and behaviors, adverse early childhood experiences, and rates of rehospitalization in sexual and gender minority compared to non-sexual and gender minority youth. RESULTS: Results show that nearly 40% of the sample identified as sexual and/or gender minority. Sexual minority youth reported higher rates of suicidal ideation (t = -6.19, p < .001), higher rates of prior suicidal behavior (Chi2 = 27.44, p < .001) and non-suicidal self-injury (Chi2 = 48.09, p < .001), and greater numbers of adverse childhood experiences (t = -3.99, p < .001); gender minority youth reported higher rates of suicidal ideation (t = -3.91 p = .001). There were no group differences for SGM youth in rates of rehospitalization in the 6-months following initial admission. These results held when controlling for sex assigned at birth and current depression status in multi-variate analyses. CONCLUSIONS: The study illuminates the importance of assessing SGM status in clinical care and highlights the need to evaluate sexual and gender minority specific risk factors for self-injurious thoughts and behaviors in youth.


Asunto(s)
Pacientes Internos , Minorías Sexuales y de Género , Adolescente , Preescolar , Heterosexualidad , Humanos , Recién Nacido , Prevalencia , Ideación Suicida
14.
J Child Adolesc Psychopharmacol ; 30(8): 522-525, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32053009

RESUMEN

Objectives: Thought problems, such as hallucinations and delusional or disorganized ideas, have been associated with increased sleep problems and risk for suicidal ideation (SI). Sleep problems have also been linked directly to suicidality in adolescence. The nature of the relationship between these symptoms among adolescents with acute suicidality is not well understood. This study aims to examine the interrelationships between thought problems, sleep difficulties, and SI in adolescents psychiatrically hospitalized for safety concerns, with the goal of informing suicide risk screening and intervention for this population. Methods: Participants included adolescents (n = 690) aged 11-18. A retrospective chart review was used to obtain scores on study measures, including the Suicidal Ideation Questionnaire Junior (SIQ-Jr), the thought problems and sleep disturbance scales on the Youth Self Report (YSR), and mental health diagnoses using the Children's Interview for Psychiatric Syndromes (ChIPS). Results: Findings indicate that SIQ-Jr scores are moderately correlated with both YSR thought problems (r = 0.51, p < 0.001) and YSR sleep disturbance (r = 0.47, p < 0.001). Further, linear regression analyses support the hypotheses that thought problems (ß = 0.28) and sleep difficulties (ß = 0.11) are uniquely associated with SI, beyond the significant effects of depression (ß = 0.36) and female sex (ß = -0.07); R2 = 0.43, F (8, 673) = 62.49, p < 0.001). Conclusions: These results suggest that sleep interventions and treatment of thought problems may be important for reducing SI, within and outside the context of depression. Furthermore, the adolescent version of the YSR may be a useful tool to evaluate these risk factors alongside other psychiatric concerns.


Asunto(s)
Adolescente Hospitalizado/psicología , Servicio de Psiquiatría en Hospital , Autoinforme , Trastornos del Sueño-Vigilia/psicología , Ideación Suicida , Adolescente , Estudios Transversales , Femenino , Humanos , Masculino , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Estudios Retrospectivos , Encuestas y Cuestionarios
15.
J Psychother Integr ; 30(2): 304-331, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34305369

RESUMEN

Early detection and prevention of psychosis has become an international priority. Much of this work has focused on youth presenting with attenuated symptoms of psychosis-those at Clinical High Risk for psychosis (CHR)-given their elevated probability of developing the full disorder in subsequent years. Individuals at CHR may be prone to exacerbated psychological distress during the COVID-19 pandemic and its subsequent physical isolation measures, due to heightened stress sensitivity and comorbid mental health problems. Telepsychotherapy holds promise for reaching this population, especially during the current COVID-19 outbreak. However, there are limited evidence-based guidelines or interventions for use of telepsychotherapy with this population. In this paper, we review common clinical issues for individuals at CHR and how they might be exacerbated by the COVID-19 pandemic; best practices for treatment and adaptations for telepsychotherapy for individuals at CHR; and highlight real clinical issues that we are currently experiencing in a United States-based specialized CHR clinic as we conduct telepsychotherapy via videoconferencing. We conclude with questions for those in the field to contemplate, as well as potential challenges and benefits in using telepsychotherapy with individuals at CHR and their families.

16.
J Nutr Educ Behav ; 49(4): 312-320.e1, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28185812

RESUMEN

OBJECTIVE: To assess the level of nutrition-sensitive agriculture competencies of graduating midlevel animal and plant sciences students in Ethiopia and identify factors associated with the attainment of competencies. DESIGN: A cross-sectional study design using structured skills observation checklists, objective written questions, and structured questionnaires was employed. SETTING: Two agriculture technical vocational education and training colleges in the 2 regions of Ethiopia. PARTICIPANTS: A total of 145 students were selected using stratified random sampling techniques from a population of 808 students with the response rate of 93%. MAIN OUTCOME MEASURES: Nutrition-sensitive agriculture competency (knowledge and skills attributes) of graduating students. ANALYSIS: Bivariate and multivariable statistical analyses were used to examine the association between the variables of students' gender, age, department, institutional ownership, and perception of learning environment and their performance in nutrition competency. RESULTS: Combined scores showed that 49% of students demonstrated mastery of nutrition competencies. Gender and institutional ownership were associated with the performance of students (P < .001); male students and students at a federal institution performed better. CONCLUSIONS AND IMPLICATIONS: The study showed low performance of students in nutrition competency and suggested the need for strengthening the curriculum, building tutors' capacity, and providing additional support to female students and regional colleges.


Asunto(s)
Agricultura/educación , Escolaridad , Conocimientos, Actitudes y Práctica en Salud , Ciencias de la Nutrición/educación , Competencia Profesional , Adulto , Factores de Edad , Crianza de Animales Domésticos/educación , Botánica/educación , Estudios Transversales , Etiopía , Femenino , Humanos , Masculino , Evaluación de Necesidades , Caracteres Sexuales , Estudiantes , Educación Vocacional , Recursos Humanos , Adulto Joven
17.
Proc Natl Acad Sci U S A ; 112(31): E4236-45, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26199412

RESUMEN

Dioxygenases of the TET (Ten-Eleven Translocation) family produce oxidized methylcytosines, intermediates in DNA demethylation, as well as new epigenetic marks. Here we show data suggesting that TET proteins maintain the consistency of gene transcription. Embryos lacking Tet1 and Tet3 (Tet1/3 DKO) displayed a strong loss of 5-hydroxymethylcytosine (5hmC) and a concurrent increase in 5-methylcytosine (5mC) at the eight-cell stage. Single cells from eight-cell embryos and individual embryonic day 3.5 blastocysts showed unexpectedly variable gene expression compared with controls, and this variability correlated in blastocysts with variably increased 5mC/5hmC in gene bodies and repetitive elements. Despite the variability, genes encoding regulators of cholesterol biosynthesis were reproducibly down-regulated in Tet1/3 DKO blastocysts, resulting in a characteristic phenotype of holoprosencephaly in the few embryos that survived to later stages. Thus, TET enzymes and DNA cytosine modifications could directly or indirectly modulate transcriptional noise, resulting in the selective susceptibility of certain intracellular pathways to regulation by TET proteins.


Asunto(s)
5-Metilcitosina/metabolismo , Proteínas de Unión al ADN/metabolismo , Desarrollo Embrionario/genética , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Proteínas Proto-Oncogénicas/metabolismo , Transcriptoma/genética , Animales , Biomarcadores/metabolismo , Blastocisto/metabolismo , Blastómeros/metabolismo , Blastómeros/patología , Linaje de la Célula , Colesterol/biosíntesis , ADN/metabolismo , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Dioxigenasas , Regulación hacia Abajo/genética , Pérdida del Embrión/metabolismo , Pérdida del Embrión/patología , Embrión de Mamíferos/patología , Impresión Genómica , Proteínas Hedgehog/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Proto-Oncogénicas/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Análisis de Secuencia de ARN , Transducción de Señal/genética
20.
Proc Natl Acad Sci U S A ; 108(35): 14566-71, 2011 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-21873190

RESUMEN

The Ten-Eleven-Translocation 2 (TET2) gene encodes a member of TET family enzymes that alters the epigenetic status of DNA by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine (5hmC). Somatic loss-of-function mutations of TET2 are frequently observed in patients with diverse myeloid malignancies, including myelodysplastic syndromes, myeloproliferative neoplasms, and chronic myelomonocytic leukemia. By analyzing mice with targeted disruption of the Tet2 catalytic domain, we show here that Tet2 is a critical regulator of self-renewal and differentiation of hematopoietic stem cells (HSCs). Tet2 deficiency led to decreased genomic levels of 5hmC and augmented the size of the hematopoietic stem/progenitor cell pool in a cell-autonomous manner. In competitive transplantation assays, Tet2-deficient HSCs were capable of multilineage reconstitution and possessed a competitive advantage over wild-type HSCs, resulting in enhanced hematopoiesis into both lymphoid and myeloid lineages. In vitro, Tet2 deficiency delayed HSC differentiation and skewed development toward the monocyte/macrophage lineage. Our data indicate that Tet2 has a critical role in regulating the expansion and function of HSCs, presumably by controlling 5hmC levels at genes important for the self-renewal, proliferation, and differentiation of HSCs.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Células Madre Hematopoyéticas/citología , Homeostasis , Proteínas Proto-Oncogénicas/fisiología , Animales , Diferenciación Celular , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Dioxigenasas , Hematopoyesis , Ratones , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Proto-Oncogénicas/genética
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