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1.
Psychol Med ; 53(2): 408-418, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-33952358

RESUMEN

BACKGROUND: This study aimed to develop, validate and compare the performance of models predicting post-treatment outcomes for depressed adults based on pre-treatment data. METHODS: Individual patient data from all six eligible randomised controlled trials were used to develop (k = 3, n = 1722) and test (k = 3, n = 918) nine models. Predictors included depressive and anxiety symptoms, social support, life events and alcohol use. Weighted sum scores were developed using coefficient weights derived from network centrality statistics (models 1-3) and factor loadings from a confirmatory factor analysis (model 4). Unweighted sum score models were tested using elastic net regularised (ENR) and ordinary least squares (OLS) regression (models 5 and 6). Individual items were then included in ENR and OLS (models 7 and 8). All models were compared to one another and to a null model (mean post-baseline Beck Depression Inventory Second Edition (BDI-II) score in the training data: model 9). Primary outcome: BDI-II scores at 3-4 months. RESULTS: Models 1-7 all outperformed the null model and model 8. Model performance was very similar across models 1-6, meaning that differential weights applied to the baseline sum scores had little impact. CONCLUSIONS: Any of the modelling techniques (models 1-7) could be used to inform prognostic predictions for depressed adults with differences in the proportions of patients reaching remission based on the predicted severity of depressive symptoms post-treatment. However, the majority of variance in prognosis remained unexplained. It may be necessary to include a broader range of biopsychosocial variables to better adjudicate between competing models, and to derive models with greater clinical utility for treatment-seeking adults with depression.


Asunto(s)
Ansiedad , Depresión , Humanos , Adulto , Depresión/psicología , Pronóstico , Resultado del Tratamiento , Escalas de Valoración Psiquiátrica
2.
BMC Med ; 19(1): 109, 2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-33952286

RESUMEN

BACKGROUND: Depression is commonly perceived as a single underlying disease with a number of potential treatment options. However, patients with major depression differ dramatically in their symptom presentation and comorbidities, e.g. with anxiety disorders. There are also large variations in treatment outcomes and associations of some anxiety comorbidities with poorer prognoses, but limited understanding as to why, and little information to inform the clinical management of depression. There is a need to improve our understanding of depression, incorporating anxiety comorbidity, and consider the association of a wide range of symptoms with treatment outcomes. METHOD: Individual patient data from six RCTs of depressed patients (total n = 2858) were used to estimate the differential impact symptoms have on outcomes at three post intervention time points using individual items and sum scores. Symptom networks (graphical Gaussian model) were estimated to explore the functional relations among symptoms of depression and anxiety and compare networks for treatment remitters and those with persistent symptoms to identify potential prognostic indicators. RESULTS: Item-level prediction performed similarly to sum scores when predicting outcomes at 3 to 4 months and 6 to 8 months, but outperformed sum scores for 9 to 12 months. Pessimism emerged as the most important predictive symptom (relative to all other symptoms), across these time points. In the network structure at study entry, symptoms clustered into physical symptoms, cognitive symptoms, and anxiety symptoms. Sadness, pessimism, and indecision acted as bridges between communities, with sadness and failure/worthlessness being the most central (i.e. interconnected) symptoms. Connectivity of networks at study entry did not differ for future remitters vs. those with persistent symptoms. CONCLUSION: The relative importance of specific symptoms in association with outcomes and the interactions within the network highlight the value of transdiagnostic assessment and formulation of symptoms to both treatment and prognosis. We discuss the potential for complementary statistical approaches to improve our understanding of psychopathology.


Asunto(s)
Depresión , Trastorno Depresivo Mayor , Adulto , Ansiedad/diagnóstico , Ansiedad/epidemiología , Trastornos de Ansiedad , Depresión/diagnóstico , Depresión/epidemiología , Humanos , Pronóstico
3.
BMC Fam Pract ; 20(1): 106, 2019 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-31351467

RESUMEN

BACKGROUND: Anxiety is under-recorded and under-treated in the UK and is under-represented in research compared with depression. Detecting anxiety can be difficult because of co-existing conditions. GPs can be reluctant to medicalise anxiety symptoms and patients can be reluctant to disclose them, for a variety of reasons. This research addresses the gap in evidence of real-life consultations of patients with anxiety and explores how physical and psychological symptoms are discussed and prioritised by patients and GPs in primary care consultations. METHODS: A mixed methods study using a baseline questionnaire, video-recorded primary care consultations and interview data with patients and GPs. RESULTS: Seventeen patients with anxiety symptoms (GAD-7 score ≥ 10) completed a questionnaire, had their consultation video-recorded and took part in a semi-structured interview. Four GPs were interviewed. The main themes that emerged from GP and patients accounts as barriers and facilitators to discussing anxiety mostly mirrored each other. The GP/patient relationship and continuity of care was the main facilitator for the discussion of anxiety in the consultation. The main barriers were: attribution of or unacknowledged symptoms; co-morbidities; and time constraints. GPs overcame these barriers by making repeat appointments and employing prioritising techniques; patients by choosing an empathetic GP. CONCLUSIONS: The findings add to the evidence base concerning the management of anxiety in primary care. The findings suggest that the discussion around anxiety is a process negotiated between the patient and the GP influenced by a range of barriers and facilitators. Co-existing depression and health anxieties can mask anxiety symptoms in patients. Good practice techniques such as bringing back patients for appointments to foster continuity of care and understanding can help disclosure and detection of anxiety symptoms. Future research could investigate this longitudinally and should include a wider range of GPs practices and GPs.


Asunto(s)
Trastornos de Ansiedad/diagnóstico , Relaciones Médico-Paciente , Atención Primaria de Salud , Actitud del Personal de Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derivación y Consulta , Encuestas y Cuestionarios , Reino Unido , Grabación en Video
4.
Diabet Med ; 32(3): 353-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25345907

RESUMEN

AIM: Insulin therapies with prandial injections offer the possibility to skip snacks or omit meals. It is unclear how many people with insulin-treated diabetes mellitus eat snacks and whether they snack for their own comfort or only on the recommendation of healthcare professionals. METHODS: In 2004, 163 consecutive people with insulin-treated diabetes seen in a university outpatient department were interviewed regarding their diet and degree of satisfaction with their meals. Fifty-five had Type 1 diabetes [age 47 years; diabetes duration 18 years; BMI 27 kg/m(2) ; HbA1c 62 mmol/mol (7.8%)], 53 had Type 2 diabetes with biphasic insulin therapy [age 68 years; diabetes duration 17 years; BMI 31 kg/m(2) ; HbA1c 60 mmol/mol (7.6%)] and 55 had Type 2 diabetes with prandial insulin therapy [age 60 years; diabetes duration 16 years; BMI 33 kg/m(2) ; HbA1c 59 mmol/mol (7.6%)]. RESULTS: Eighty per cent of those with Type 1 diabetes ate snacks, together with 77% of the Type 2 diabetes/biphasic group and 62% of the Type 2 diabetes/prandial group. Most participants (91% Type 1 diabetes, 88% Type 2 diabetes/biphasic group, 82% Type 2 diabetes/prandial group) liked to have snacks. The time at which they ate snacks was the same for both diabetes types. There were no differences between participants with Type 1 diabetes who snacked and those who did not in terms of age (P = 0.350), BMI (P = 0.368), HbA1c (P = 0.257) and time since diagnosis (P = 0.846). Participants with Type 2 diabetes who ate snacks were older than those who did not (biphasic: P = 0.006; prandial: P = 0.008). There were no differences in terms of BMI (biphasic: P = 0.731; prandial: P = 0.393), HbA1c (biphasic: P = 0.747; prandial: P = 0.616) and time since diagnosis (biphasic: P = 0.06; prandial: P = 0.620). CONCLUSIONS: Most people with insulin-treated diabetes eat snacks voluntarily and not because of physicians' instructions. There were no correlations between the use of snacks and HbA1c , BMI and time since diagnosis, except that the participants with Type 2 diabetes who ate snacks were older.


Asunto(s)
Peso Corporal/fisiología , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Conducta Alimentaria/psicología , Hemoglobina Glucada/metabolismo , Insulina/uso terapéutico , Calidad de Vida/psicología , Bocadillos/psicología , Adulto , Factores de Edad , Anciano , Estudios Transversales , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Humanos , Hipoglucemia/prevención & control , Hipoglucemiantes/uso terapéutico , Masculino , Persona de Mediana Edad , Satisfacción Personal , Factores de Tiempo , Resultado del Tratamiento
7.
Fam Pract ; 29(2): 163-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21890841

RESUMEN

BACKGROUND: Mild or subclinical hypothyroidism [raised thyroid-stimulating hormone (TSH) but normal free thyroxine (T4)] affects 5-10% of adults. Symptoms are non-specific and TSH levels are needed for diagnosis. OBJECTIVES: We explore the relationship between thyroid function and psychological distress and investigate the usefulness of an expert-designed Thyroid Symptom Questionnaire (TSQ) in identifying hypothyroidism. METHODS: DEPTH (DEPression and THyroid) is a cross-sectional study of 325 patients recruited from general practices in Bristol, for whom thyroid function tests were requested by the GP. Subjects completed the TSQ, General Health Questionnaire (GHQ-12) and Patient Health Questionnaire (PHQ) and had blood tests for TSH and free T4. RESULTS: The mean age was 45.7 years; 252 subjects (78%) were female; median TSH was 1.6. Psychological morbidity in this population is high: 54.2% have a GHQ-12 score >3, indicating psychological distress. We found no relationship between TSH and psychological distress [adjusted odds ratio 1.02 (95% confidence interval 0.91-1.13), P = 0.78]. The prevalence of hypothyroidism was 6.2% (95% confidence interval 3.8-9.5%). We found no evidence of an unadjusted association between TSQ score and subclinical hypothyroidism [adjusted odds ratio of 1.09 (95% confidence interval 0.95-1.24), P = 0.23]. CONCLUSIONS: Those referred for thyroid function tests, although no more likely than others to have hypothyroidism, have high rates of psychological distress. When mild (subclinical) hypothyroidism is detected in patients with psychological distress, it is important that GPs are aware that this is likely to be coincidental rather than causal and offer appropriate treatment.


Asunto(s)
Estrés Psicológico/psicología , Enfermedades de la Tiroides/psicología , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Hipotiroidismo/diagnóstico , Hipotiroidismo/psicología , Masculino , Persona de Mediana Edad , Estrés Psicológico/diagnóstico , Encuestas y Cuestionarios , Enfermedades de la Tiroides/diagnóstico , Pruebas de Función de la Tiroides/estadística & datos numéricos , Tirotropina/sangre , Tiroxina/sangre , Adulto Joven
8.
Phys Rev Lett ; 107(24): 240603, 2011 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-22242984

RESUMEN

We derive a simple formula for the fluctuations of the time average x(t) around the thermal mean (eq) for overdamped brownian motion in a binding potential U(x). Using a backward Fokker-Planck equation, introduced by Szabo, Schulten, and Schulten in the context of reaction kinetics, we show that for ergodic processes these finite measurement time fluctuations are determined by the Boltzmann measure. For the widely applicable logarithmic potential, ergodicity is broken. We quantify the large nonergodic fluctuations and show how they are related to a superaging correlation function.

10.
Epidemiol Psychiatr Sci ; 30: e42, 2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-34085616

RESUMEN

AIMS: To determine whether age, gender and marital status are associated with prognosis for adults with depression who sought treatment in primary care. METHODS: Medline, Embase, PsycINFO and Cochrane Central were searched from inception to 1st December 2020 for randomised controlled trials (RCTs) of adults seeking treatment for depression from their general practitioners, that used the Revised Clinical Interview Schedule so that there was uniformity in the measurement of clinical prognostic factors, and that reported on age, gender and marital status. Individual participant data were gathered from all nine eligible RCTs (N = 4864). Two-stage random-effects meta-analyses were conducted to ascertain the independent association between: (i) age, (ii) gender and (iii) marital status, and depressive symptoms at 3-4, 6-8, and 9-12 months post-baseline and remission at 3-4 months. Risk of bias was evaluated using QUIPS and quality was assessed using GRADE. PROSPERO registration: CRD42019129512. Pre-registered protocol https://osf.io/e5zup/. RESULTS: There was no evidence of an association between age and prognosis before or after adjusting for depressive 'disorder characteristics' that are associated with prognosis (symptom severity, durations of depression and anxiety, comorbid panic disorderand a history of antidepressant treatment). Difference in mean depressive symptom score at 3-4 months post-baseline per-5-year increase in age = 0(95% CI: -0.02 to 0.02). There was no evidence for a difference in prognoses for men and women at 3-4 months or 9-12 months post-baseline, but men had worse prognoses at 6-8 months (percentage difference in depressive symptoms for men compared to women: 15.08% (95% CI: 4.82 to 26.35)). However, this was largely driven by a single study that contributed data at 6-8 months and not the other time points. Further, there was little evidence for an association after adjusting for depressive 'disorder characteristics' and employment status (12.23% (-1.69 to 28.12)). Participants that were either single (percentage difference in depressive symptoms for single participants: 9.25% (95% CI: 2.78 to 16.13) or no longer married (8.02% (95% CI: 1.31 to 15.18)) had worse prognoses than those that were married, even after adjusting for depressive 'disorder characteristics' and all available confounders. CONCLUSION: Clinicians and researchers will continue to routinely record age and gender, but despite their importance for incidence and prevalence of depression, they appear to offer little information regarding prognosis. Patients that are single or no longer married may be expected to have slightly worse prognoses than those that are married. Ensuring this is recorded routinely alongside depressive 'disorder characteristics' in clinic may be important.


Asunto(s)
Antidepresivos , Depresión , Adulto , Antidepresivos/uso terapéutico , Ansiedad , Depresión/diagnóstico , Depresión/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estado Civil , Pronóstico
11.
J Exp Med ; 176(3): 787-92, 1992 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-1512542

RESUMEN

Interleukin 1 (IL-1) is a pluripotent cytokine involved in mediating a variety of physiological processes, including induction of cell proliferation upon wound healing. Treatment of quiescent FS-4 human dermal fibroblast cells with IL-1 activates c-myc gene transcription, and nuclear localization of NF-kappa B. Previously, we have noted that the murine c-myc gene contains two functional NF-kappa B sites located at -1101 to -1081 bp (upstream regulatory element [URE]) and +440 to +459 bp (internal regulatory element [IRE]) relative to the P1 promoter. Here we have demonstrated that IL-1 treatment induced binding of NF-kappa B-like proteins (p50/p65) to these c-myc elements. Heterologous promoter-CAT constructs driven by multiple copies of either the URE or IRE were IL-1 inducible when transfected into FS-4 cells. In contrast, constructs harboring elements with two G to C residue conversions, such that they were no longer able to bind NF-kappa B, were not responsive to IL-1. Mutation of these two base pairs at both NF-kappa B sites within a c-myc promoter/exon I-CAT construct, resulted in loss of inducibility with IL-1 upon transfection into quiescent FS-4 cells. Thus, IL-1 significantly induces c-myc expression through positive regulation by NF-kappa B, suggesting a role for this family of factors in activation of proliferation associated with wound healing.


Asunto(s)
Regulación de la Expresión Génica , Genes myc , Interleucina-1/fisiología , FN-kappa B/fisiología , Transcripción Genética , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , ADN , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/efectos de la radiación , Fibroblastos , Factores de Transcripción Forkhead , Humanos , Ratones , Datos de Secuencia Molecular , Proteínas Nucleares/metabolismo , Proteínas Nucleares/efectos de la radiación , Regiones Promotoras Genéticas , Secuencias Reguladoras de Ácidos Nucleicos , Activación Transcripcional , Rayos Ultravioleta
12.
Space Sci Rev ; 216(8): 137, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33268910

RESUMEN

The Mars 2020 Perseverance rover is equipped with a next-generation engineering camera imaging system that represents an upgrade over previous Mars rover missions. These upgrades will improve the operational capabilities of the rover with an emphasis on drive planning, robotic arm operation, instrument operations, sample caching activities, and documentation of key events during entry, descent, and landing (EDL). There are a total of 16 cameras in the Perseverance engineering imaging system, including 9 cameras for surface operations and 7 cameras for EDL documentation. There are 3 types of cameras designed for surface operations: Navigation cameras (Navcams, quantity 2), Hazard Avoidance Cameras (Hazcams, quantity 6), and Cachecam (quantity 1). The Navcams will acquire color stereo images of the surface with a 96 ∘ × 73 ∘ field of view at 0.33 mrad/pixel. The Hazcams will acquire color stereo images of the surface with a 136 ∘ × 102 ∘ at 0.46 mrad/pixel. The Cachecam, a new camera type, will acquire images of Martian material inside the sample tubes during caching operations at a spatial scale of 12.5 microns/pixel. There are 5 types of EDL documentation cameras: The Parachute Uplook Cameras (PUCs, quantity 3), the Descent stage Downlook Camera (DDC, quantity 1), the Rover Uplook Camera (RUC, quantity 1), the Rover Descent Camera (RDC, quantity 1), and the Lander Vision System (LVS) Camera (LCAM, quantity 1). The PUCs are mounted on the parachute support structure and will acquire video of the parachute deployment event as part of a system to characterize parachute performance. The DDC is attached to the descent stage and pointed downward, it will characterize vehicle dynamics by capturing video of the rover as it descends from the skycrane. The rover-mounted RUC, attached to the rover and looking upward, will capture similar video of the skycrane from the vantage point of the rover and will also acquire video of the descent stage flyaway event. The RDC, attached to the rover and looking downward, will document plume dynamics by imaging the Martian surface before, during, and after rover touchdown. The LCAM, mounted to the bottom of the rover chassis and pointed downward, will acquire 90 ∘ × 90 ∘ FOV images during the parachute descent phase of EDL as input to an onboard map localization by the Lander Vision System (LVS). The rover also carries a microphone, mounted externally on the rover chassis, to capture acoustic signatures during and after EDL. The Perseverance rover launched from Earth on July 30th, 2020, and touchdown on Mars is scheduled for February 18th, 2021.

13.
J Cell Biol ; 69(2): 393-406, 1976 May.
Artículo en Inglés | MEDLINE | ID: mdl-944188

RESUMEN

The content of myosin in plasmodia of the myxomycete Physarum polycephalum was measured by an immunological technique, quantitative microcomplement (C') fixation. Migrating plasmodia (starved after growth on rolled oats) contained 0.60 +/- 0.08 (SD) mg myosin per g fresh plasmodia. Myosin comprised 0.77% +/- 0.05 (SD) of the total plasmodial protein. When total plasmodial proteins were separated by electrophoresis on SDS-polyacrylamide gels, a large amount of protein appeared in a band comigrating with muscle actin. Densitometry performed after Coomassie blue staining indicated that as much as 15-25% of the total protein in the plasmodium could be actin. This gives an actin/myosin ratio by weight in the myxomycete plasmodium as high as 19-33, a very "actin-rich" actomyosin compared with rabbit skeletal muscle actomyosin with an actin/myosin ratio of 0.6. Starvation stimulates rapid migration and is correlated with a higher percent of both myosin and actin in the total protein of the plasmodium compared with normally growing cultures. Immunological cross-reaction of myosins from a variety of species was measured by C' fixation using an antiserum produced against purified native myosin from P. polycephalum. Although myxomycete and vertebrate striated muscle myosins have very similar morphological and biochemical properties, and apparently possess similar binding properties to F-actin, only myosins from myxomycetes in the order Physarales, rather closely related to P. polycephalum, gave detectable cross-reactions. This finding suggests that many amino acid sequences in myosin have been variable during evolution.


Asunto(s)
Actinas/análisis , Miosinas/análisis , Mixomicetos/análisis , Physarum/análisis , Animales , Antígenos , Pollos , Pruebas de Fijación del Complemento , Reacciones Cruzadas , Densitometría , Electroforesis en Gel de Poliacrilamida , Músculos/análisis , Miosinas/inmunología , Conejos , Especificidad de la Especie
14.
Science ; 223(4640): 1034-40, 1984 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-6695192

RESUMEN

There is increasing recognition that federal food safety laws and policies need to be revised. Congressional debate on proposed amendments to the Food, Drug, and Cosmetic Act has generated several different perspectives on how the food safety laws should be changed. Before a consensus can be reached, scientists, regulators, the food industry, and consumers will have to review such complex and controversial issues as the level of acceptable risk, the value of risk-benefit analysis, the proper role of independent scientific review, and the reliability of quantitative risk assessment.


Asunto(s)
Legislación Alimentaria , United States Food and Drug Administration , Carcinógenos , Aditivos Alimentarios , Análisis de los Alimentos , Colorantes de Alimentos , Contaminación de Alimentos , Legislación de Medicamentos , Legislación Alimentaria/tendencias , Residuos de Plaguicidas , Riesgo , Seguridad , Estados Unidos
15.
Science ; 266(5185): 596-604, 1994 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-7939714

RESUMEN

Within the fertilized egg lies the information necessary to generate a diversity of cell types in the precise pattern of tissues and organs that comprises the vertebrate body. Seminal embryological experiments established the importance of induction, or cell interactions, in the formation of embryonic tissues and provided a foundation for molecular studies. In recent years, secreted gene products capable of inducing or patterning embryonic tissues have been identified. Despite these advances, embryologists remain challenged by fundamental questions: What are the endogenous inducing molecules? How is the action of an inducer spatially and temporally restricted? How does a limited group of inducers give rise to diversity of tissues? In this review, the focus is on the induction and patterning of mesodermal and neural tissues in the frog Xenopus laevis, with an emphasis on families of secreted molecules that appear to underlie inductive events throughout vertebrate embryogenesis.


Asunto(s)
Inducción Embrionaria , Sustancias de Crecimiento/fisiología , Mesodermo/fisiología , Sistema Nervioso/embriología , Animales , Ectodermo/fisiología , Desarrollo Embrionario , Genes , Xenopus laevis/embriología
16.
Science ; 266(5190): 1528-37, 1994 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-7985023

RESUMEN

Extracellular signaling proteins encoded by the hedgehog (hh) multigene family are responsible for the patterning of a variety of embryonic structures in vertebrates and invertebrates. The Drosophila hh gene has now been shown to generate two predominant protein species that are derived by an internal autoproteolytic cleavage of a larger precursor. Mutations that reduced the efficiency of autoproteolysis in vitro diminished precursor cleavage in vivo and also impaired the signaling and patterning activities of the HH protein. The two HH protein species exhibited distinctive biochemical properties and tissue distribution, and these differences suggest a mechanism that could account for the long- and short-range signaling activities of HH in vivo.


Asunto(s)
Proteínas de Drosophila , Drosophila/metabolismo , Embrión no Mamífero/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas/metabolismo , Transducción de Señal , Secuencia de Aminoácidos , Animales , Línea Celular , Drosophila/embriología , Drosophila/genética , Inducción Embrionaria , Regulación del Desarrollo de la Expresión Génica , Genes de Insecto , Proteínas Hedgehog , Modelos Biológicos , Datos de Secuencia Molecular , Mutación , Precursores de Proteínas/química , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Proteínas/química , Proteínas/genética , Serina Endopeptidasas/química
17.
Science ; 293(5537): 2080-4, 2001 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-11486055

RESUMEN

One of the most dominant influences in the patterning of multicellular embryos is exerted by the Hedgehog (Hh) family of secreted signaling proteins. Here, we identify a segment polarity gene in Drosophila melanogaster, skinny hedgehog (ski), and show that its product is required in Hh-expressing cells for production of appropriate signaling activity in embryos and in the imaginal precursors of adult tissues. The ski gene encodes an apparent acyltransferase, and we provide genetic and biochemical evidence that Hh proteins from ski mutant cells retain carboxyl-terminal cholesterol modification but lack amino-terminal palmitate modification. Our results suggest that ski encodes an enzyme that acts within the secretory pathway to catalyze amino-terminal palmitoylation of Hh, and further demonstrate that this lipid modification is required for the embryonic and larval patterning activities of the Hh signal.


Asunto(s)
Aciltransferasas/genética , Aciltransferasas/metabolismo , Proteínas de Drosophila , Drosophila melanogaster/genética , Proteínas de Insectos/metabolismo , Ácido Palmítico/metabolismo , Transducción de Señal , Acilación , Aciltransferasas/química , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Tipificación del Cuerpo , Colesterol/metabolismo , Drosophila melanogaster/embriología , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/metabolismo , Expresión Génica , Genes de Insecto , Proteínas Hedgehog , Proteínas de Insectos/química , Proteínas de Insectos/genética , Datos de Secuencia Molecular , Mutación , Estructura Terciaria de Proteína , Transgenes
18.
Artículo en Inglés | MEDLINE | ID: mdl-18565746

RESUMEN

Previous research suggests that low n-3 long-chain polyunsaturated fatty acid (n-3PUFA) status is associated with higher levels of depression in clinical populations. This analysis aimed to investigate the relationship between depressed mood and n-3PUFA status in a non-clinical population. The analysis was conducted on data collected as part of a large randomized controlled trial investigating the impact of n-3PUFA supplementation on depressed mood in a community-based population. On entry into the trial, data on depressed mood were collected using the Depression, Anxiety and Stress Scales (DASS) and the Beck Depression Inventory (BDI). Plasma concentrations of various n-3PUFAs and n-6 long-chain polyunsaturated fatty acids (n-6PUFAs) were obtained from fasting venous blood samples, and various demographics were also measured. Using regression, there was no evidence of an association between either measure of depressed mood and any of the measures of n-3PUFA status or of n-6PUFA:n-3PUFA ratios. Clear associations were also not found when demographic factors were included in the analyses. These findings suggest that n-3PUFAs may not have a role in the aetiology of minor depression. This is also consistent with the results of other studies that have not demonstrated an association between depressed mood and n-3PUFA status in non-clinical populations and epidemiological studies that have not demonstrated an association between depressed mood and n-3PUFA intake in these populations.


Asunto(s)
Depresión/sangre , Ácidos Grasos Omega-3/sangre , Adulto , Factores de Edad , Depresión/diagnóstico , Ácidos Grasos Omega-6/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carencia Psicosocial , Análisis de Regresión , Estaciones del Año , Factores Sexuales , Encuestas y Cuestionarios
19.
Curr Biol ; 5(8): 944-55, 1995 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-7583153

RESUMEN

BACKGROUND: The hedgehog (hh) family of secreted signaling proteins is responsible for developmental patterning in a variety of systems, including the neural tube, limbs and somites. Within the neural tube, at the level of the spinal cord, products of the vertebrate gene sonic hedgehog (shh) are proposed to function as a ventral patterning influence, with the capability of inducing floor plate and motor neurons. RESULTS: We report the isolation of tiggy-winkle hedgehog (twhh), a novel member of the zebrafish hh gene family. Both twhh and shh are expressed in the ventral midline of the embryonic zebrafish neural tube and brain, but twhh expression becomes limited to the neural tube, whereas shh is also expressed in the notochord. Both genes are expressed in the developing brain, in domains that include a discrete region in the floor of the diencephalon, located between the sites of the future optic stalks. Using pax-2 and pax-6 as markers of proximo-distal fate within the developing eye, we found that ectopic expression of either hh gene promoted proximal fates and suppressed distal fates. In contrast, proximal fates were lost in cyclops mutant embryos, which lack twhh- and shh-expressing forebrain cells. Both twhh and shh proteins undergo autoproteolytic processing in vivo; a fragment corresponding to the amino-terminal cleavage product was sufficient to carry out all signaling activities associated with twhh in eye and brain development. CONCLUSIONS: These findings suggest that secreted signals encoded by members of the hedgehog gene family, emanating from the ventral midline of the neural tube, not only play important roles in dorso-ventral patterning of the brain but also appear to constitute an early patterning activity along the proximo-distal axis of the developing eyes.


Asunto(s)
Encéfalo/embriología , Proteínas de Drosophila , Ojo/embriología , Regulación del Desarrollo de la Expresión Génica , Proteínas/metabolismo , Transactivadores , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Encéfalo/metabolismo , Cartilla de ADN , Drosophila/genética , Inducción Embrionaria/genética , Ojo/metabolismo , Proteínas Hedgehog , Mesodermo , Datos de Secuencia Molecular , Notocorda/embriología , Notocorda/metabolismo , Proteínas/genética , Homología de Secuencia de Aminoácido , Pez Cebra/genética , Proteínas de Pez Cebra
20.
Mol Cell Biol ; 10(6): 2448-57, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2342456

RESUMEN

Interferon-stimulated gene factor 2 (ISGF2) was purified from HeLa cells treated with alpha interferon. The factor, a single polypeptide of 56 kilodaltons (kDa), bound both to the central 9 base pairs of the 15-base-pair interferon-stimulated response element (ISRE) that is required for transcriptional activation of interferon-stimulated genes and to the PRD-I regulatory element of the beta interferon gene. ISGF2 was a phosphoprotein, and dephosphorylation in vitro reduced its DNA-binding activity. However, conditions that changed the amount of ISGF2 did not change the phosphorylated isoforms in vivo. ISGF2 in unstimulated cells existed in trace amounts and was induced by both alpha interferon and gamma interferon as well as by virus infection. Plasmid-bearing Escherichia coli clones encoding ISGF2 were selected with antibody against purified ISGF2. Sequence analysis revealed that the ISGF2 protein was the same as that encoded by the cDNA clone IRF-1, which has been claimed to activate transcription of interferon genes. We show that transcription of the ISGF2 gene was induced by alpha interferon, gamma interferon, and double-stranded RNA. However, ISGF2 was neither necessary nor sufficient for induced transcription of the beta interferon gene, while the factor NF kappa B was clearly involved.


Asunto(s)
Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica , Genes , Interferón Tipo I/genética , Fosfoproteínas , Regiones Promotoras Genéticas , Transcripción Genética , Secuencia de Bases , Núcleo Celular/metabolismo , Cromatografía de Afinidad , Cromatografía en Gel , Clonación Molecular , Proteínas de Unión al ADN/aislamiento & purificación , Proteínas de Unión al ADN/metabolismo , Células HeLa/inmunología , Humanos , Factor 1 Regulador del Interferón , Interferón Tipo I/farmacología , Datos de Secuencia Molecular , Peso Molecular , Sondas de Oligonucleótidos
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