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1.
Rapid Commun Mass Spectrom ; 35(17): e9147, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34145645

RESUMO

RATIONALE: Information on the temperature of formation or alteration of carbonate minerals can be obtained by measuring the abundance of the isotopologues 47 and 48 (Δ47 and Δ48 values) of CO2 released during acid dissolution. The combination of these two proxies can potentially provide a greater insight into the temperature of formation, particularly if the carbonate minerals form by non-equilibrium processes. METHODS: We have precipitated calcium carbonates at seven temperatures between 5 and 65°C and measured their δ48 values using a Thermo-253 plus isotope ratio mass spectrometer. The values were transformed to Δ48 values in the conventional manner and then converted to the carbon dioxide equilibrium scale. RESULTS: Using the Δ48 values, we have established an empirical calibration between temperature and Δ48 values: [Formula: see text] CONCLUSIONS: The calibration line produced allows the determination of the temperature of natural carbonates using the Δ48 values and agrees with the measurements of the Δ47 and Δ48 values of some carbonates assumed to have formed under equilibrium conditions.

2.
Biol Lett ; 16(2): 20190865, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32019462

RESUMO

The Gulf of Mexico (GoM) is home to the world's largest remaining wild oyster fisheries, but baseline surveys needed to assess habitat condition are recent and may represent an already-shifted reference state. Here, we use prehistoric oysters from archaeological middens to show that oyster size, an indicator of habitat function and population resilience, declined prior to the earliest assessments of reef condition in an area of the GoM previously considered pristine. Stable isotope sclerochronlogy reveals extirpation of colossal oysters occurred through truncated life history and slowed growth. More broadly, our study suggests that management strategies affected by shifting baselines may overestimate resilience and perpetuate practices that risk irreversible decline.


Assuntos
Crassostrea , Animais , Ecossistema , Pesqueiros , Golfo do México , México
3.
Pediatr Res ; 80(6): 768-776, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27500537

RESUMO

Glucocorticoid induction of pulmonary surfactant involves a mesenchyme-derived protein first characterized in 1978 by Smith and termed fibroblast-pneumocyte factor (FPF). Despite a number of agents having been postulated as being FPF, its identity has remained obscure. In the past decade, three strong candidates for FPF have arisen. This review examines the evidence that keratinocyte growth factor (KGF), leptin or neuregulin-1ß (NRG-1ß) act as FPF or components of it. As with FPF production, glucocorticoids enhance the concentration of each of these agents in fibroblast-conditioned media. Moreover, each stimulates the synthesis of surfactant-associated phospholipids and proteins in type II pneumocytes. Further, some have unique activities, for example, KGF also minimizes lung injury through enhanced epithelial cell proliferation and NRG-1ß enhances surfactant phospholipid secretion and ß-adrenergic receptor activity in type II cells. However, even though these agents have attributes in common with FPF, it is inappropriate to specify any one of these agents as FPF. Rather, it appears that each contributes to separate mesenchymal-epithelial signaling mechanisms involved in different aspects of lung development. Given that the production of pulmonary surfactant is essential for postnatal survival, it is reasonable to suggest that several mechanisms independently regulate surfactant synthesis.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Células Epiteliais Alveolares/citologia , Células Epiteliais Alveolares/metabolismo , Animais , Proliferação de Células/fisiologia , Fator 7 de Crescimento de Fibroblastos/metabolismo , Glucocorticoides/metabolismo , Glucocorticoides/farmacologia , Humanos , Leptina/metabolismo , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Neuregulina-1/metabolismo , Fosfolipídeos/metabolismo , Surfactantes Pulmonares/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais
4.
Soc Psychiatry Psychiatr Epidemiol ; 46(4): 291-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20191262

RESUMO

OBJECTIVES: The goal of this study was to determine childhood clinical predictors of quality of life (QoL) in early adulthood in children with obsessive-compulsive disorder (OCD). METHODS: A longitudinal cohort study was conducted with 36 (out of 62 eligible) children with OCD, interviewed once at childhood baseline (mean age 12.1 ± 2.1, range 8.0-15.8), and again in early adulthood after an average follow-up interval of 9 years. QoL was measured in adulthood with the longitudinal interval follow-up evaluation range of impaired functioning tool (LIFE-RIFT). RESULTS: Forty-two percent of children experienced a remission of OCD symptoms by early adulthood. OCD appeared to most strongly impair the interpersonal relationships and work domains of QoL. QoL and severity of OCD and anxiety symptoms were significantly associated in early adulthood. Primary hoarding symptoms in childhood predicted poor QoL in adulthood. Increased symptoms in the forbidden thoughts dimension in both childhood and adulthood were associated with improved adulthood QoL. CONCLUSIONS: Children for whom OCD symptoms remitted by adulthood showed no evidence of residual impairment in QoL, whereas children whose OCD symptoms failed to remit by adulthood showed at most mild impairment in QoL. Hoarding symptoms in childhood appear to portend not only the persistence of OCD symptoms but also poorer QoL in early adulthood.


Assuntos
Transtorno Obsessivo-Compulsivo/psicologia , Adolescente , Adulto , Criança , Feminino , Previsões , Humanos , Estudos Longitudinais , Masculino , Qualidade de Vida , Índice de Gravidade de Doença , Perfil de Impacto da Doença , Tempo , Adulto Jovem
5.
Br J Hosp Med (Lond) ; 76(9): 510-5, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26352709

RESUMO

Incident reporting systems are vital to safe health care. Existing systems should be made simpler and more accessible, proper feedback given to those who complete reports and lessons learned from investigations shared more widely. A major shift in culture is required so health-care professionals feel safe completing incident reports.

6.
Artigo em Inglês | MEDLINE | ID: mdl-24255802

RESUMO

BACKGROUND: Deep brain stimulation (DBS) remains an experimental but promising treatment for patients with severe refractory Gilles de la Tourette syndrome (TS). Controversial issues include the selection of patients (age and clinical presentation), the choice of brain targets to obtain optimal patient-specific outcomes, and the risk of surgery- and stimulation-related serious adverse events. METHODS: This report describes our open-label experience with eight patients with severe refractory malignant TS treated with DBS. The electrodes were placed in the midline thalamic nuclei or globus pallidus, pars internus, or both. Tics were clinically assessed in all patients pre- and postoperatively using the Modified Rush Video Protocol and the Yale Global Tic Severity Scale (YGTSS). RESULTS: Although three patients had marked postoperative improvement in their tics (>50% improvement on the YGTSS), the majority did not reach this level of clinical improvement. Two patients had to have their DBS leads removed (one because of postoperative infection and another because of lack of benefit). DISCUSSION: Our clinical experience supports the urgent need for more data and refinements in interventions and outcome measurements for severe, malignant, and medication-refractory TS. Because TS is not an etiologically homogenous clinical entity, the inclusion criteria for DBS patients and the choice of brain targets will require more refinement.

7.
J Child Adolesc Psychopharmacol ; 20(4): 237-47, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20807062

RESUMO

OBJECTIVE: This article reviews the available scientific literature concerning the neurobiological substrates of Tourette's disorder (TD). METHODS: The electronic databases of PubMed, ScienceDirect, and PsycINFO were searched for relevant studies using relevant search terms. RESULTS: Neuropathological as well as structural and functional neuroimaging studies of TD implicate not only the sensorimotor corticostriatal circuit, but also the limbic and associative circuits as well. Preliminary evidence also points to abnormalities in the frontoparietal network that is thought to maintain adaptive online control. Evidence supporting abnormalities in dopaminergic and noradrenergic neurotransmission remains strong, although the precise mechanisms remain the subject of speculation. CONCLUSION: Structural and functional abnormalities in multiple parallel corticostriatal circuits may underlie the behavioral manifestations of TD and related neuropsychiatric disorders over the course of development. Further longitudinal research is needed to elucidate these neurobiological substrates.


Assuntos
Dopamina/metabolismo , Norepinefrina/metabolismo , Síndrome de Tourette/fisiopatologia , Animais , Corpo Estriado/fisiopatologia , Humanos , Neurotransmissores/metabolismo
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