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1.
Brain Spine ; 3: 101735, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37383457

RESUMO

Background: There is wide-ranging published literature around cranioplasty following traumatic brain injury (TBI) and stroke, but the heterogeneity of outcomes limits the ability for meta-analysis. Consensus on appropriate outcome measures has not been reached, and given the clinical and research interest, a core outcome set (COS) would be beneficial. Objectives: To collate outcomes currently reported across the cranioplasty literature which will subsequently be used in developing a cranioplasty COS. Methods: This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. All full-text English studies with more than ten patients (prospective) or more than 20 patients (retrospective) published after 1990 examining outcomes in CP were eligible for inclusion. Results: The review included 205 studies from which 202 verbatim outcomes were extracted, grouped into 52 domains, and categorised into one or more of the OMERACT 2.0 framework core area(s). The total numbers of studies that reported outcomes in the core areas are 192 (94%) pathophysiological manifestations/ 114 (56%) resource use/economic impact/ 94 (46%) life impact/mortality 20 (10%). In addition, there are 61 outcome measures used in the 205 studies across all domains. Conclusion: This study shows considerable heterogeneity in the types of outcomes used across the cranioplasty literature, demonstrating the importance and necessity of developing a COS to help standardise reporting across the literature.

2.
Front Surg ; 9: 864385, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35656088

RESUMO

Decompressive craniectomy (DC) is an operation where a large section of the skull is removed to accommodate brain swelling. Patients who survive will usually require subsequent reconstruction of the skull using either their own bone or an artificial prosthesis, known as cranioplasty. Cranioplasty restores skull integrity but can also improve neurological function. Standard care following DC consists of the performance of cranioplasty several months later as historically, there was a concern that earlier cranioplasty may increase the risk of infection. However, recent systematic reviews have challenged this and have demonstrated that an early cranioplasty (within three months after DC) may enhance neurological recovery. However, patients are often transferred to a rehabilitation unit following their acute index admission and before their cranioplasty. A better understanding of the pathophysiological effects of cranioplasty and the relationship of timing and complications would enable more focused patient tailored rehabilitation programs, thus maximizing the benefit following cranioplasty. This may maximise recovery potential, possibly resulting in improved functional and cognitive gains, enhancement of quality of life and potentially reducing longer-term care needs. This narrative review aims to update multi-disciplinary team regarding cranioplasty, including its history, pathophysiological consequences on recovery, complications, and important clinical considerations both in the acute and rehabilitation settings.

3.
Parkinsonism Relat Disord ; 10(7): 425-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15465400

RESUMO

Hereditary spastic paraplegia with thin corpus callosum is a rare degenerative disease, which is characterized by a progressive weakness of the lower limbs with a hypoplastic corpus callosum, and is often associated with other symptoms such as mental impairment, amyotrophy, sensory disturbances, dysuria, nystagmus and cataract. We describe two siblings (brother and sister) who showed a thin corpus callosum on MRI, one of whom showed the pure form of progressive spastic paraplegia, while the other showed predominant levodopa-responsive parkinsonism. The present cases are illustrative of a phenotypic heterogeneity in the same family of spastic paraplegia with a thin corpus callosum, despite the identical neuroimaging findings, and also presented another form of autosomal recessive juvenile levodopa-responsive parkinsonism.


Assuntos
Antiparkinsonianos/uso terapêutico , Corpo Caloso/patologia , Levodopa/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Paraplegia Espástica Hereditária/complicações , Adolescente , Benzotropina/uso terapêutico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Eletroencefalografia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Debilidade Muscular/etiologia , Debilidade Muscular/fisiopatologia , Testes Neuropsicológicos , Selegilina/uso terapêutico , Paraplegia Espástica Hereditária/patologia , Tremor/etiologia , Tremor/fisiopatologia
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(3 Pt 1): 031103, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12366095

RESUMO

We study an escape process of a noisy particle with a time varying load. We present an effective nonperturbative method which works even when the time varying load amplitude is comparable to other parameters. It is based on the idea that for every instant of time, we know the quasiadiabatic eigenspectrum and the quasiadiabatic eigenfunctions of the instantaneous system. We show that when two time-varying quasiadiabatic eigenvalues in the spectrum get close to each other, the amplitudes of the quasiadiabatic eigenfuntions show an abrupt change; therefore, the escape rate is highly affected.

5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(4 Pt 2): 046124, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12443276

RESUMO

We study an ionization process for a particle bound by an attractive delta(x) potential of a certain depth defined on a finite lattice under an external periodic force. Ionization coincides with the time when first two time dependent energy eigenvalues get close to each other. We use a slow driving force away from the resonance frequency. We also observe intermittent high frequency oscillation which can be analyzed with two level approximation.

7.
J Mol Biol ; 385(5): 1470-80, 2009 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-18845160

RESUMO

Calmodulin (CaM) is a ubiquitous second messenger protein that regulates a variety of structurally and functionally diverse targets in response to changes in Ca(2+) concentration. CaM-dependent protein kinase II (CaMKII) and calcineurin (CaN) are the prominent CaM targets that play an opposing role in many cellular functions including synaptic regulation. Since CaMKII and CaN compete for the available Ca(2+)/CaM, the differential affinity of these enzymes for CaM is crucial for achieving a balance in Ca(2+) signaling. We used the computational protein design approach to modify CaM binding specificity for these two targets. Starting from the X-ray structure of CaM in complex with the CaM-binding domain of CaMKII, we optimized CaM interactions with CaMKII by introducing mutations into the CaM sequence. CaM optimization was performed with a protein design program, ORBIT, using a modified energy function that emphasized intermolecular interactions in the sequence selection procedure. Several CaM variants were experimentally constructed and tested for binding to the CaMKII and CaN peptides using the surface plasmon resonance technique. Most of our CaM mutants demonstrated small increase in affinity for the CaMKII peptide and substantial decrease in affinity for the CaN peptide compared to that of wild-type CaM. Our best CaM design exhibited an about 900-fold increase in binding specificity towards the CaMKII peptide, becoming the highest specificity switch achieved in any protein-protein interface through the computational protein design approach. Our results show that computational redesign of protein-protein interfaces becomes a reliable method for altering protein binding affinity and specificity.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/química , Cálcio/metabolismo , Calmodulina/química , Simulação por Computador , Modelos Moleculares , Sequência de Aminoácidos , Sítios de Ligação , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Cristalografia por Raios X , Dados de Sequência Molecular , Mutação , Ligação Proteica
8.
Proc Natl Acad Sci U S A ; 103(38): 13968-73, 2006 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-16966599

RESUMO

Changes in synaptic strength that underlie memory formation in the CNS are initiated by pulses of Ca2+ flowing through NMDA-type glutamate receptors into postsynaptic spines. Differences in the duration and size of the pulses determine whether a synapse is potentiated or depressed after repetitive synaptic activity. Calmodulin (CaM) is a major Ca2+ effector protein that binds up to four Ca2+ ions. CaM with bound Ca2+ can activate at least six signaling enzymes in the spine. In fluctuating cytosolic Ca2+, a large fraction of free CaM is bound to fewer than four Ca2+ ions. Binding to targets increases the affinity of CaM's remaining Ca2+-binding sites. Thus, initial binding of CaM to a target may depend on the target's affinity for CaM with only one or two bound Ca2+ ions. To study CaM-dependent signaling in the spine, we designed mutant CaMs that bind Ca2+ only at the two N-terminal or two C-terminal sites by using computationally designed mutations to stabilize the inactivated Ca2+-binding domains in the "closed" Ca2+-free conformation. We have measured their interactions with CaMKII, a major Ca2+/CaM target that mediates initiation of long-term potentiation. We show that CaM with two Ca2+ ions bound in its C-terminal lobe not only binds to CaMKII with low micromolar affinity but also partially activates kinase activity. Our results support the idea that competition for binding of CaM with two bound Ca2+ ions may influence significantly the outcome of local Ca2+ signaling in spines and, perhaps, in other signaling pathways.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Cálcio/metabolismo , Calmodulina/metabolismo , Sinalização do Cálcio/fisiologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Calmodulina/química , Calmodulina/genética , Simulação por Computador , Ativação Enzimática , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Dobramento de Proteína , Sinapses/fisiologia
9.
Immunology ; 109(1): 76-86, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12709020

RESUMO

Bisphenol A (BPA) and p-nonylphenol (NP) are representative endocrine disruptors (EDs) that may have adverse effects on human health. The influence of these compounds on allergic immune responses remains unclear. In this study, we have examined the effects of BPA and NP on production of interleukin-4 (IL-4), a pro-inflammatory cytokine closely associated with allergic immune responses. Both BPA and NP significantly enhanced IL-4 production in keyhole limpet haemocyanin (KLH)-primed CD4+ T cells in a concentration-dependent manner. Treatment with BPA or NP in vivo resulted in significant increase of IL-4 production in CD4+ T cells and of antigen-specific immunoglobulin E (IgE) levels in the sera of KLH-primed mice. Furthermore, BPA and NP enhanced the activation of IL-4 gene promoter in EL4 T cells transiently transfected with IL-4 promoter/reporter constructs, and the enhancing effect mapped to a region in the IL-4 promoter containing binding sites for nuclear factor (NF)-AT. Activation of T lymphocytes by phorbol 12-myristate 13-acetate/ionomycin resulted in markedly enhanced binding activities to the NF-AT site, which significantly increased upon addition of BPA or NP, as demonstrated by the electrophoretic mobility shift assay, indicating that the transcription factor NF-AT was involved in the enhancing effect of BPA and NP on IL-4 production. The enhancement of IL-4 production by BPA or NP was significantly reduced by nitrendipine, a blocker of Ca2+ influx, and by FK506, a calcineurin inhibitor. FK506 inhibited the NF-AT-DNA binding activity and IL-4 gene promoter activity enhanced by BPA or NP. These results represent the first report describing possible enhancement of allergic response by EDs through increasing IL-4 production in CD4+ T cells and antigen-specific IgE levels in the sera via the stimulation of Ca2+/calcineurin-dependent NF-AT activation.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Estrogênios não Esteroides/farmacologia , Interleucina-4/biossíntese , Proteínas Nucleares , Fenóis/farmacologia , Animais , Compostos Benzidrílicos , Linfócitos T CD4-Positivos/imunologia , Cálcio/imunologia , Células Cultivadas , Proteínas de Ligação a DNA/imunologia , Relação Dose-Resposta Imunológica , Feminino , Imunoglobulina E/sangue , Interleucina-4/genética , Linfonodos/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Fatores de Transcrição NFATC , Regiões Promotoras Genéticas/imunologia , Fatores de Transcrição/imunologia
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