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1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 138(5): 383-386, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33608232

RESUMO

BACKGROUND: Intraoperative injury of the thoracic duct is an uncommon complication of head and neck surgery, which is difficult to manage and associated with serious consequences. We report a case of lymphorrhoea of the neck refractory to all the usual treatments that resolved in response to a treatment strategy described in thoracic and visceral surgery: use of a sympathomimetic drug, etilefrine. To our knowledge and after review of the literature, this is the first reported case of lymphorrhoea of the neck treated by etilefrine. CASE REPORT: Our patient presented massive lymphatic fluid leakage following left neck dissection as part of the management of oropharyngeal cancer with lymph node metastases. The treatments usually proposed, such as intraoperative repair and appropriate dietary and drug management, were not effective, resulting in multiple, severe complications. After evaluation of the benefit-risk balance, treatment with etilefrine was introduced at the dosages proposed in the literature for the management of chylothorax. This treatment allowed complete resolution of the lymphatic fluid leak after one week. DISCUSSION: Etilefrine can therefore be added to the treatment options for the management of lymphatic fluid leaks refractory to the usual treatments.


Assuntos
Quilotórax , Etilefrina , Quilotórax/cirurgia , Humanos , Pescoço , Esvaziamento Cervical , Ducto Torácico
2.
Alzheimers Dement (N Y) ; 6(1): e12096, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163613

RESUMO

IMPORTANCE: Adults with Down syndrome (DS) are at high-risk of revealing Alzheimer's disease (AD) pathology, in part due to the triplication of chromosome 21 encoding the amyloid precursor protein. Adults with DS are uniformly affected by AD pathology by their 30's and have a 70% to 80% chance of clinical dementia by their 60's. Our previous studies have assessed longitudinal changes in amyloid beta (Aß) accumulation in DS. OBJECTIVE: The goal of the present study was to assess the presence of brain tau using [18F]AV-1451 positron emission tomography (PET) in DS and to assess the relationship of brain tau pathology to Aß using Pittsburgh Compound B (PiB)-PET. DESIGN: Cohort study. SETTING: Multi-center study. PARTICIPANTS: Participants consisted of a sample of individuals with DS and sibling controls recruited from the community; exclusion criteria included contraindications for magnetic resonance imaging (MRI) and/or a medical or psychiatric condition that impaired cognitive functioning. EXPOSURES: PET brain scans to assess Aß ([11C]PiB) and tau ([18F]AV-1451) burden. MAIN OUTCOMES AND MEASURES: Multiple linear regression models (adjusted for chronological age, sex and performance site) were used to examine associations between regional [18F]AV-1451 standard uptake value ratio (SUVR) (based on regions associated with Braak stages 1-6) and global [11C]PiB SUVR (as both a continuous and dichotomous variable). RESULTS: A cohort of 156 participants (mean age = 39.05, SD(8.4)) were examined. These results revealed a significant relationship between in vivo Aß and tau pathology in DS. As a dichotomous variable, [18F]AV-1451 retention was higher in each Braak region in PiB(+) participants. We also found, based on our statistical models, starting with the Braak 3 region of interest (ROI), an acceleration of [18F]AV-1451 SUVR deposition with [11C]PiB SUVR increases.

3.
Toxicol Res (Camb) ; 6(5): 631-653, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30090531

RESUMO

Systems biology combines comprehensive molecular analyses with quantitative modeling to understand the characteristics of a biological system as a whole. Leveraging a similar approach, systems toxicology aims to decipher complex biological responses following exposures. This work reports a systems toxicology meta-analysis in the context of in vitro assessment of a candidate modified-risk tobacco product (MRTP) using three human organotypic cultures of the aerodigestive tract (buccal, bronchial, and nasal epithelia). Complementing a series of functional measures, a causal network enrichment analysis of transcriptomic data was used to compare quantitatively the biological impact of aerosol from the Tobacco Heating System (THS) 2.2, a candidate MRTP, with 3R4F cigarette smoke (CS) at similar nicotine concentrations. Lower toxicity was observed in all cultures following exposure to THS2.2 aerosol compared with 3R4F CS. Because of their morphological differences, a smaller exposure impact was observed in the buccal (stratified epithelium) compared with the bronchial and nasal (pseudostratified epithelium). However, the causal network enrichment approach supported a similar mechanistic impact of CS across the three cultures, including the impact on xenobiotic, oxidative stress, and inflammatory responses. At comparable nicotine concentrations, THS2.2 aerosol elicited reduced and more transient effects on these processes. To demonstrate the benefits of additional data modalities, we employed a newly established targeted mass-spectrometry marker panel to further confirm the reduced cellular stress responses elicited by THS2.2 aerosol compared with 3R4F CS in the nasal culture. Overall, this work demonstrates the applicability and robustness of the systems toxicology approach for in vitro inhalation toxicity assessment.

4.
Transl Psychiatry ; 5: e693, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26645628

RESUMO

The metabotropic glutamate receptor subtype 5 (mGluR5) has been implicated in the pathophysiology of mood and anxiety disorders and is a potential treatment target in major depressive disorder (MDD). This study compared brain mGluR5 binding in elderly patients suffering from MDD with that in elderly healthy volunteers using positron emission tomography (PET) and [(11)C]ABP688. Twenty elderly (mean age: 63.0 ± 6.3) subjects with MDD and twenty-two healthy volunteers in the same age range (mean age: 66.4 ± 7.3) were examined with PET after a single bolus injection of [(11)C]ABP688, with many receiving arterial sampling. PET images were analyzed on a region of interest and a voxel level to compare mGluR5 binding in the brain between the two groups. Differences in [(11)C]ABP688 binding between patients with early- and late-onset depression were also assessed. In contrast to a previously published report in a younger cohort, no significant difference in [(11)C]ABP688 binding was observed between elderly subjects with MDD and healthy volunteers. [(11)C]ABP688 binding was also similar between subgroups with early- or late-onset depression. We believe this is the first study to examine mGluR5 expression in depression in the elderly. Although future work is required, results suggest potential differences in the pathophysiology of elderly depression versus depression earlier in life.


Assuntos
Encéfalo/metabolismo , Radioisótopos de Carbono , Transtorno Depressivo Maior/metabolismo , Oximas , Tomografia por Emissão de Pósitrons , Piridinas , Receptor de Glutamato Metabotrópico 5/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
5.
Neuroimage Clin ; 9: 479-83, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26594630

RESUMO

The amyloid imaging agent, Pittsburgh Compound-B, binds with high affinity to ß-amyloid (Aß) in the brain, and it is well established that PiB also shows non-specific retention in white matter (WM). However, little is known about retention of PiB in areas of white matter hyperintensities (WMH), abnormalities commonly seen in older adults. Further, it is hypothesized that WMH are related to both cognitive dysfunction and Aß deposition. The goal of the present study was to explore PiB retention in both normal-appearing WM (NAWM) and WMH in a group of elderly, cognitively normal individuals. In a group of cognitively normal elderly (n = 64; 86.5 ± 2.6 years) two analyses were applied: (1) ROIs were placed over periventricular areas in which WMH caps are commonly seen on all subjects, regardless of WMH burden or size. (2) Subject-specific maps of NAWM and WMH were co-registered with the PiB-PET images and mean SUVR values were calculated in these NAWM and WMH maps. PiB retention was significantly reduced in the ROIs of subjects with high WMH compared to subjects with low WMH. Additionally, in subjects with high WMH, there was significantly lower PiB retention in subject-specific maps of WMH compared to NAWM, which was not observed in subjects with low WMH, likely because of the small size of WMH maps in this group. These data suggest that WM in areas of WMH binds PiB less effectively than does normal WM. Further exploration of this phenomenon may lead to insights about the molecular basis of the non-specific retention of amyloid tracers in white matter.


Assuntos
Compostos de Anilina/farmacocinética , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/patologia , Tomografia por Emissão de Pósitrons/métodos , Tiazóis/farmacocinética , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Idoso de 80 Anos ou mais , Ventrículos Cerebrais/metabolismo , Feminino , Humanos , Masculino , Substância Branca/metabolismo
6.
Toxicol In Vitro ; 29(8): 2102-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26277032

RESUMO

Cigarette smoking causes serious and fatal diseases. The best way for smokers to avoid health risks is to quit smoking. Using modified risk tobacco products (MRTPs) may be an alternative to reduce the harm caused for those who are unwilling to quit smoking, but little is known about the toxic effects of MRTPs, nor were the molecular mechanisms of toxicity investigated in detail. The toxicity of an MRTP and the potential molecular mechanisms involved were investigated in high-content screening tests and whole genome transcriptomics analyses using human bronchial epithelial cells. The prototypic (p)MRTP that was tested had less impact than reference cigarette 3R4F on the cellular oxidative stress response and cell death pathways. Higher pMRTP aerosol extract concentrations had impact on pathways associated with the detoxification of xenobiotics and the reduction of oxidative damage. A pMRTP aerosol concentration up to 18 times higher than the 3R4F caused similar perturbation effects in biological networks and led to the perturbation of networks related to cell stress, and proliferation biology. These results may further facilitate the development of a systems toxicology-based impact assessment for use in future risk assessments in line with the 21st century toxicology paradigm, as shown here for an MRTP.


Assuntos
Aerossóis/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Nicotiana , Mucosa Respiratória/citologia , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Brônquios , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional , Regulação da Expressão Gênica , Humanos , Transcriptoma
7.
Clin Genet ; 85(5): 476-81, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23692385

RESUMO

Ciliopathies are heterogeneous disorders sharing different clinical signs due to a defect at the level of the primary cilia/centrosome complex. Postaxial polydactyly is frequently reported in ciliopathies, especially in Bardet-Biedl syndrome (BBS). Clinical features and genetic results observed in a pair of dizygotic twins with BBS are reported. The following manifestations were present: retinitis pigmentosa, bilateral insertional polydactyly, cognitive impairment and renal dysfunction. X-rays of the hands confirmed the presence of a 4th mesoaxial extra-digit with Y-shaped metacarpal bones. The sequencing of LZTFL1 identified a missense mutation (NM_020347.2: p.Leu87Pro; c.260T>C) and a nonsense mutation (p.Glu260*; c.778G>T), establishing a compound heterozygous status for the twins. A major decrease of LZTFL1 transcript and protein was observed in the patient's fibroblasts. This is the second report of LZTFL1 mutations in BBS patients confirming LZTFL1 as a BBS gene. Interestingly, the only two families reported in literature thus far with LZTFL1 mutations have in common mesoaxial polydactyly, a very uncommon feature for BBS. This special subtype of polydactyly in BBS patients is easily identified on clinical examination and prompts for priority sequencing of LZTFL1 (BBS17).


Assuntos
Síndrome de Bardet-Biedl/genética , Dedos/anormalidades , Mutação/genética , Polidactilia/genética , Dedos do Pé/anormalidades , Fatores de Transcrição/genética , Adulto , Síndrome de Bardet-Biedl/fisiopatologia , Análise Mutacional de DNA , Feminino , Dedos/fisiopatologia , Heterozigoto , Humanos , Linhagem , Polidactilia/fisiopatologia , Dedos do Pé/fisiopatologia , Gêmeos
8.
J Anim Sci ; 90(13): 5099-106, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22851236

RESUMO

A 4-yr study was conducted at Corona Range and Livestock Research Center, Corona, NM, to establish if a protein-dense self-fed supplement could substitute for a traditional hand-fed (range cube) supplement that is less protein dense and minimize or maintain cow BW and BCS during late gestation and the subsequent steer progeny feedlot performance, health, and economic viability. Late gestation cows received one of 3 supplementation strategies: 1) 36% CP cottonseed meal base supplement (CSM; positive control) fed 3 times per week, 2) self-fed supplement (SMP) comprising 50% animal protein sources (blood meal and feather meal) and 50% trace mineral package, or 3) brief and intermittent supplementation of CSM based on periods of acute environmental stress (VAR; negative control) by ranch management. Initiation of supplementation varied across years due to changing forage conditions and climatically imposed grazing constraints but always ended approximately 2 wks before calving each year. Across all 4 yr, supplement consumption averaged 0.65, 0.21, and 0.04 kg·head(-1)·d(-1) for CSM, SMP, and VAR, respectively. After weaning, steers were preconditioned for 45 d and were received and treated as custom fed commercial cattle at a feedlot in mid November each year. Cow BW and BCS were not influenced (P ≥ 0.13) by prepartum supplementation; however, the strategy did have an effect on BW and BCS change with cows managed in the VAR group. Cows managed in the VAR group lost the greatest (P < 0.05) amount of BW and BCS whereas no differences were measured between CSM and SMP groups. Prepartum supplementation strategies did not influence (P = 0.98) pregnancy rates. Calf weaning, initial feedlot and final BW, and HCW were unaffected (P ≥ 0.80) by prepartum supplementation of the dam. Steers from dams fed CSM and VAR had a greater percentage treated for sickness than SMP steers (P = 0.03), which resulted in a tendency (P = 0.07) for medicine costs to be greater in steers from CSM and VAR cows. The use of a self-fed package supplement was equally effective as use of a traditional hand-fed, oilseed-based supplement in maintaining BW and BCS during late gestation. In addition, these results imply that although nutrition treatment of cows during the prenatal period had no effect on calf growth performance, calves from cows fed SMP had improved feedlot health.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais/análise , Animais , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Bovinos/crescimento & desenvolvimento , Feminino , Masculino , New Mexico , Gravidez , Distribuição Aleatória , Estações do Ano
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(5 Pt 2): 056312, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21728652

RESUMO

We provide an experimental demonstration that the circular hydraulic jump represents a hydrodynamic white hole or gravitational fountain (the time reverse of a black hole) by measuring the angle of the Mach cone created by an object in the "supersonic" inner flow region. We emphasize the general character of this gravitational analogy by showing theoretically that the white hole horizon constitutes a stationary and spatial saddle-node bifurcation within dynamical-systems theory. We also demonstrate that the inner region has a "superluminal" dispersion relation, that is, that the group velocity of the surface waves increases with frequency, and discuss some possible consequences with respect to the robustness of Hawking radiation. Finally, we point out that our experiment shows a concrete example of a possible "trans-Planckian distortion" of black or white holes.

10.
Neurology ; 77(1): 39-47, 2011 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-21700583

RESUMO

OBJECTIVE: This study examined the relationship between postmortem precuneus cholinergic enzyme activity, Pittsburgh compound B (PiB) binding, and soluble amyloid-ß concentration in mild cognitive impairment (MCI) and Alzheimer disease (AD). METHODS: Choline acetyltransferase (ChAT) activity, [(3)H]PiB binding, and soluble amyloid-ß(1-42) (Aß42) concentration were quantified in precuneus tissue samples harvested postmortem from subjects with no cognitive impairment (NCI), MCI, and mild AD and correlated with their last antemortem Mini-Mental State Examination (MMSE) score and postmortem pathologic evaluation according to the National Institute on Aging-Reagan criteria, recommendations of the Consortium to Establish a Registry for Alzheimer's Disease, and Braak stage. RESULTS: Precuneus ChAT activity was lower in AD than in NCI and was comparable between MCI and NCI. Precuneus [(3)H]PiB binding and soluble Aß42 levels were elevated in MCI and significantly higher in AD than in NCI. Across all case subjects, reduced ChAT activity was associated with increased [(3)H]PiB binding, increased soluble Aß42, lower MMSE score, presence of the APOE*4 allele, and more advanced AD pathology. CONCLUSIONS: Despite accumulating amyloid burden, cholinergic enzyme activity is stable in the precuneus during prodromal AD. A decline in precuneus ChAT activity occurs only in clinical AD, when PiB binding and soluble Aß42 levels are substantially elevated compared with those in MCI. Anti-amyloid interventions in MCI case subjects with a positive PiB PET scan may aid in reducing cholinergic deficits and cognitive decline later in the disease process.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Lobo Parietal/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Compostos de Anilina , Benzotiazóis/farmacocinética , Estudos de Casos e Controles , Colina O-Acetiltransferase/metabolismo , Feminino , Humanos , Masculino , Emaranhados Neurofibrilares/patologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Mudanças Depois da Morte , Escalas de Graduação Psiquiátrica , Ensaio Radioligante , Cintilografia , Tiazóis , Trítio/farmacocinética
11.
Genes Brain Behav ; 10(3): 299-308, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21091868

RESUMO

G protein-coupled receptor (GPCR) associated sorting protein-1 (GASP-1) is suspected to play a key role in recycling and degradation of several GPCRs. In a previous study, we have shown that GASP-1-knock-out (GASP-1-KO) mice displayed deficits in acquiring a cocaine self-administration task, associated with an exacerbated down-regulation of striatal dopaminergic and cholinergic receptors. Among several possibilities, GASP-1 deficiency could have impaired memory processes underlying the acquisition of the operant conditioning task. Therefore, the present study investigated cognitive performances of GASP-1-KO mice and their wild-type littermates (WT) in a broad variety of memory tasks. Consistent with a deficit in procedural memory, GASP-1-KO mice showed delayed acquisition of a food-reinforced bar-press task. During water-maze training in hidden- or visible-platform paradigms, mutant and WT mice acquired the tasks at the same rate. However, GASP-1 mice exhibited persistent thigmotaxic swimming, longer distance to the platform, and reduced swim speed. There was no deficit in several tasks requiring simple behavioral responses (Barnes maze, object recognition and passive avoidance tasks). Thus, the ability to acquire and/or express complex responses seems affected in GASP-1-deficient mice. Hippocampal functions were preserved, as the retention of an acquired memory in spatial tasks remained unaffected. The pattern of behavioral deficits observed in GASP-1-KO mice is coherent with current knowledge on the role of striatal GPCRs in acquisition/expression of skilled behavior and in motivation. Together with the previous findings, the so far established phenotype of GASP-1-KO mice makes them a potentially exciting tool to study striatal functions.


Assuntos
Doenças dos Gânglios da Base/genética , Proteínas de Transporte/genética , Transtornos Cognitivos/genética , Deficiências da Aprendizagem/genética , Transtornos da Memória/genética , Animais , Doenças dos Gânglios da Base/metabolismo , Doenças dos Gânglios da Base/fisiopatologia , Comportamento Animal/fisiologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/fisiopatologia , Corpo Estriado/metabolismo , Corpo Estriado/fisiopatologia , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intracelular , Deficiências da Aprendizagem/metabolismo , Deficiências da Aprendizagem/fisiopatologia , Masculino , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Quimeras de Transplante/genética
12.
Eur Phys J E Soft Matter ; 33(1): 11-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20848154

RESUMO

Patterns formed by centimeter scale bubbles on the free surface of a viscous liquid are investigated in a cylindrical container. These bubbles emerge periodically at the surface and interact with each other in the central zone. Their radial emission, due to interaction and radial surface flow, leads to the formation of a variety of patterns. Different star-like and spiral patterns appear spontaneously by increasing the bubble emergence frequency. It is found that these patterns are due to a constant angular shift in the bubble emission direction. Measurements of this angular shift show a supercritical bifurcation accompanied by a transition from a pattern of two opposed straight arms to spiral patterns. By applying the tools and concepts from the study of leaf arrangement in botany (phyllotaxis), the recognized patterns and the mechanism of the pattern formation are discussed. Close similarities to the leaf arrangement are found in the behavior of the angular shift and the patterns. These findings suggest that the observed patterns are formed by a packing mechanism of successively appearing elements (bubbles), which is similar to that of the leaves at the earliest stage of phyllotaxis.


Assuntos
Hidrodinâmica , Movimento (Física) , Óleos/química , Silicones/química , Propriedades de Superfície , Viscosidade
13.
Neurology ; 74(10): 807-15, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20147655

RESUMO

OBJECTIVE: To investigate whether longitudinal declines in cognition are associated with higher fibrillar amyloid-beta (Abeta) deposition in vivo in individuals without dementia. METHOD: [(11)C]PiB images were obtained to measure fibrillar Abeta burden in 57 participants without dementia from the Baltimore Longitudinal Study of Aging. Participants (33 men, 24 women) had a mean (SD) age of 78.7 (6.2) years. Six participants (4 men, 2 women) had mild cognitive impairment defined as Clinical Dementia Rating = 0.5. To measure [(11)C]PiB retention, distribution volume ratios (DVR) for 15 regions of interest were estimated by fitting a simplified reference tissue model to the measured time activity curves. Mixed effects regression was used to predict cognitive trajectories over time using data before and including time of PiB (mean follow-up 10.8 years), with mean cortical DVR, age at baseline, sex, and education as independent predictors. Voxel-based analysis identified local associations. RESULTS: [(11)C]PiB retention was higher in older individuals. Greater declines over time in mental status and verbal learning and memory, but not visual memory, were associated significantly with higher PiB retention. Voxel-based analysis showed significant associations in frontal and lateral temporal regions. CONCLUSIONS: Higher Abeta deposition is associated with greater longitudinal decline in mental status and verbal memory in the preceding years. The differential association for verbal but not visual memory may reflect the greater reliance of verbal word list learning on prefrontal regions, which show early Abeta deposition. Prospective imaging may help distinguish between individuals with evolving neuropathology who develop accelerated cognitive decline vs those with normal aging.


Assuntos
Amiloide/metabolismo , Compostos de Anilina , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/metabolismo , Tiazóis , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico , Radioisótopos de Carbono , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Entrevista Psiquiátrica Padronizada , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons/métodos , Estudos Retrospectivos
14.
PLoS One ; 5(12): e15166, 2010 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-21203385

RESUMO

Accurate conversion of magnetic resonance spectra to quantitative units of concentration generally requires compensation for differences in coil loading conditions, the gains of the various receiver amplifiers, and rescaling that occurs during post-processing manipulations. This can be efficiently achieved by injecting a precalibrated, artificial reference signal, or pseudo-signal into the data. We have previously demonstrated, using in vitro measurements, that robust pseudo-signal injection can be accomplished using a second coil, called the injector coil, properly designed and oriented so that it couples inductively with the receive coil used to acquire the data. In this work, we acquired nonlocalized phosphorous magnetic resonance spectroscopy measurements from resting human tibialis anterior muscles and used pseudo-signal injection to calculate the Pi, PCr, and ATP concentrations. We compared these results to parallel estimates of concentrations obtained using the more established phantom replacement method. Our results demonstrate that pseudo-signal injection using inductive coupling provides a robust calibration factor that is immune to coil loading conditions and suitable for use in human measurements. Having benefits in terms of ease of use and quantitative accuracy, this method is feasible for clinical use. The protocol we describe could be readily translated for use in patients with mitochondrial disease, where sensitive assessment of metabolite content could improve diagnosis and treatment.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Espectroscopia de Ressonância Magnética/métodos , Trifosfato de Adenosina/química , Calibragem , Humanos , Modelos Biológicos , Modelos Estatísticos , Músculo Esquelético/metabolismo , Imagens de Fantasmas , Fosfatos/química , Fósforo/química , Reprodutibilidade dos Testes
15.
Neurology ; 73(15): 1193-9, 2009 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-19822868

RESUMO

BACKGROUND: PET imaging using [(18)F]fluorodeoxyglucose (FDG) and [(11)C]Pittsburgh compound B (PIB) have been proposed as biomarkers of Alzheimer disease (AD), as have CSF measures of the 42 amino acid beta-amyloid protein (Abeta(1-42)) and total and phosphorylated tau (t-tau and p-tau). Relationships between biomarkers and with disease severity are incompletely understood. METHODS: Ten subjects with AD, 11 control subjects, and 34 subjects with mild cognitive impairment from the Alzheimer's Disease Neuroimaging Initiative underwent clinical evaluation; CSF measurement of Abeta(1-42), t-tau, and p-tau; and PIB-PET and FDG-PET scanning. Data were analyzed using continuous regression and dichotomous outcomes with subjects classified as "positive" or "negative" for AD based on cutoffs established in patients with AD and controls from other cohorts. RESULTS: Dichotomous categorization showed substantial agreement between PIB-PET and CSF Abeta(1-42) measures (91% agreement, kappa = 0.74), modest agreement between PIB-PET and p-tau (76% agreement, kappa = 0.50), and minimal agreement for other comparisons (kappa <0.3). Mini-Mental State Examination score was significantly correlated with FDG-PET but not with PIB-PET or CSF Abeta(1-42). Regression models adjusted for diagnosis showed that PIB-PET was significantly correlated with Abeta(1-42), t-tau, and p-tau(181p), whereas FDG-PET was correlated only with Abeta(1-42). CONCLUSIONS: PET and CSF biomarkers of Abeta agree with one another but are not related to cognitive impairment. [(18)F]fluorodeoxyglucose-PET is modestly related to other biomarkers but is better related to cognition. Different biomarkers for Alzheimer disease provide different information from one another that is likely to be complementary.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Biomarcadores/metabolismo , Transtornos Cognitivos/diagnóstico por imagem , Idoso , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Compostos de Anilina/metabolismo , Biomarcadores/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Estudos de Casos e Controles , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/metabolismo , Feminino , Fluordesoxiglucose F18/metabolismo , Humanos , Masculino , Fragmentos de Peptídeos/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons , Escalas de Graduação Psiquiátrica , Tiazóis/metabolismo , Proteínas tau/líquido cefalorraquidiano
16.
J Anim Sci ; 87(11): 3656-68, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19648488

RESUMO

Purified lipopolysaccharide (LPS) infusion in cattle induces clinical and metabolic responses similar to gram-negative bacterial infection. Effects of LPS and dietary protein on rectal temperature, serum hormones, haptoglobin, plasma urea N and AA, and N balance were evaluated in 24 steers (250 +/- 2.8 kg of BW). Treatments were a 2 x 3 factorial of LPS (0 vs. 1.5 microg/kg of BW; -LPS vs. +LPS) and diets containing (DM basis) 1) 14.5% CP, 11.6% ruminally degradable protein (RDP), and 2.9% ruminally undegradable protein (RUP; CP14.5CON); 2) 16.3% CP, 13.4% RDP, and 2.9% RUP (CP16RDP); and 3) 16.1% CP, 11.2% RDP, and 4.9% RUP (CP16RUP). Diet RDP and RUP were altered using casein, fish meal, and corn gluten meal. Steers were adapted to diets (1.1 Mcal/kg of NE(g); DM fed at 1.8% BW) for 14 d and were infused (intravenously 1 mL/min) with LPS (in 100 mL of saline) on d 15. Rectal temperature and serum cortisol, prolactin, haptoglobin, and insulin increased, glucose initially increased and then declined, and serum thyroxine and triiodothyronine decreased for +LPS vs. -LPS steers (LPS x hour; P < 0.01). Serum IGF-I was less (P < 0.01) for +LPS vs. -LPS steers. Plasma urea N increased in response to LPS (LPS x hour; P = 0.02) and was greater for +LPS steers fed CP16RDP and CP16RUP vs. CP14.5CON, but greater in -LPS steers fed CP16RUP vs. CP16RDP and CP14.5CON (LPS x diet; P = 0.04). Plasma Met, Thr, Leu, Ile, Phe, Trp, Gly, Ser, Asn, and Tyr decreased, and plasma Ala increased in response to LPS (LPS x hour; P < 0.01). Plasma Orn initially increased and then decreased in +LPS vs. -LPS steers (LPS x hour; P < 0.01). No LPS x diet interactions (P > or = 0.15) occurred for DM, OM, NDF and N intake, fecal excretion, or apparent digestibility. Dietary DM, OM, NDF, and N intake, and retained N were less (P < 0.01) for +LPS than -LPS steers. Total N intake, apparent N digestibility, and retained N were greater (P < or = 0.05) for steers fed CP16RDP and CP16RUP vs. CP14.5CON. An LPS x diet interaction (P = 0.05) occurred for N retention (% N intake) because N retention was less for +LPS than -LPS steers when fed CP14.5CON, but not different between +LPS and -LPS steers when fed CP16RDP and CP16RUP. These results demonstrate that LPS infusion alters serum hormones, plasma AA, and N balance in cattle and imply that growing steers exposed to LPS may require greater dietary protein concentrations to account for altered intake and metabolic AA demand.


Assuntos
Bovinos/fisiologia , Proteínas Alimentares/farmacologia , Lipopolissacarídeos/farmacologia , Nitrogênio/metabolismo , Aminoácidos/sangue , Animais , Glicemia/análise , Nitrogênio da Ureia Sanguínea , Temperatura Corporal , Bovinos/metabolismo , Digestão/fisiologia , Haptoglobinas/análise , Hidrocortisona/sangue , Insulina/sangue , Masculino , Prolactina/sangue
17.
Brain ; 132(Pt 5): 1310-23, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19042931

RESUMO

Although beta-amyloid (Abeta) plaques are a primary diagnostic criterion for Alzheimer's disease, this pathology is commonly observed in the brains of non-demented older individuals. To explore the importance of this pathology in the absence of dementia, we compared levels of amyloid deposition (via 'Pittsburgh Compound-B' (PIB) positron emission tomography (PET) imaging) to hippocampus volume (HV) and episodic memory (EM) in three groups: (i) normal controls (NC) from the Berkeley Aging Cohort (BAC NC, n = 20); (ii) normal controls (NC) from the Alzheimer's disease neuroimaging initiative (ADNI NC, n = 17); and (iii) PIB+ mild cognitive impairment subjects from the ADNI (ADNI PIB+ MCI, n = 39). Age, gender and education were controlled for in each statistical model, and HV was adjusted for intracranial volume (aHV). In BAC NC, elevated PIB uptake was significantly associated with smaller aHV (P = 0.0016) and worse EM (P = 0.0086). Within ADNI NC, elevated PIB uptake was significantly associated with smaller aHV (P = 0.047) but not EM (P = 0.60); within ADNI PIB+ MCI, elevated PIB uptake was significantly associated with both smaller aHV (P = 0.00070) and worse EM (P = 0.046). To further understand these relationships, a recursive regression procedure was conducted within all ADNI NC and PIB+ MCI subjects (n = 56) to test the hypothesis that HV mediates the relationship between Abeta and EM. Significant correlations were found between PIB index and EM (P = 0.0044), PIB index and aHV (P < 0.0001), as well as between aHV and EM (P < 0.0001). When both aHV and PIB were included in the same model to predict EM, aHV remained significant (P = 0.0015) whereas PIB index was no longer significantly associated with EM (P = 0.50). These results are consistent with a model in which Abeta deposition, hippocampal atrophy, and EM occur sequentially in elderly subjects, with Abeta deposition as the primary event in this cascade. This pattern suggests that declining EM in older individuals may be caused by Abeta-induced hippocampus atrophy.


Assuntos
Peptídeos beta-Amiloides/análise , Hipocampo/patologia , Transtornos da Memória/patologia , Fatores Etários , Idoso , Envelhecimento/fisiologia , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Doença de Alzheimer/psicologia , Compostos de Anilina , Atrofia , Radioisótopos de Carbono , Estudos de Casos e Controles , Escolaridade , Feminino , Hipocampo/química , Hipocampo/diagnóstico por imagem , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Transtornos da Memória/diagnóstico por imagem , Transtornos da Memória/psicologia , Pessoa de Meia-Idade , Análise Multivariada , Tamanho do Órgão , Tomografia por Emissão de Pósitrons/métodos , Escalas de Graduação Psiquiátrica , Compostos Radiofarmacêuticos , Fatores Sexuais , Tiazóis
18.
J Anim Sci ; 87(2): 681-92, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18849391

RESUMO

Metabolic demand for sulfur-containing AA increases during inflammation in nonruminants. Therefore, Met supplementation may alleviate the negative effects of infection on N balance. Effects of gram-negative bacterial lipopolysaccharide (LPS) and supplemental dietary Met on N balance, serum hormones and haptoglobin, and plasma urea-N and AA were evaluated in 20 Angus-cross steers (BW = 262 +/- 6.3 kg). Treatments (2 x 2 factorial) were infusion of no LPS (-LPS) or a prolonged low dose of LPS (+LPS) and dietary supplementation of no (-MET) or 14 g/d (+MET) of rumen-protected Met (providing 7.9 g/d of dl-Met). Steers were adapted to a roughage-based diet (DMI = 1.4% of BW daily) and supplemental Met for 14 d, and were then infused (1 mL/min via intravenous catheter) with LPS on d 1 (2 microg/kg of BW) and 3 (1 microg/kg of BW) of a 5-d collection period. Blood was collected on d 1, before LPS infusion, and at 2, 4, 6, 8, 10, 12, and 24 h after LPS challenge. Diet samples, feed refusals, feces, and urine were collected daily for 5 d. Rectal temperature and serum concentrations of cortisol, prolactin, tumor necrosis factor-alpha, and haptoglobin increased, whereas thyroxine and triiodothyronine decreased for +LPS vs. -LPS steers (LPS x h; P < 0.01). Plasma urea-N was greater for +LPS than -LPS steers (LPS; P = 0.03), and serum IGF-1 was not affected (P > or = 0.26) by LPS or Met. Plasma concentrations of Thr, Lys, Leu, Ile, Phe, Trp, Asn, Glu, and Orn decreased, plasma Ala increased, and Gly and Ser initially increased, then declined in +LPS vs. -LPS steers (LPS x h; P < or = 0.04). Plasma Met was greater for +MET than -MET steers before LPS infusion, but declined in +MET steers after LPS infusion (LPS x Met x h; P < 0.01). By design, DMI was not different, but DM digested was less (P = 0.04) for +LPS than -LPS steers. Infusion of LPS did not affect (P > or = 0.24) N intake, fecal N excretion, or N digested, but resulted in greater (P < 0.01) urinary N excretion and less (P < 0.01) N retention. The absence of an LPS x Met interaction (P = 0.26) for N retention indicates that supplemental Met does not improve the N utilization of growing beef steers exposed to a gram-negative bacterial endotoxin. Decreases in plasma concentrations of several essential AA in +LPS steers suggest that metabolic demand for these AA likely increased in steers exposed to endotoxin.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Digestão/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Metionina/administração & dosagem , Nitrogênio/metabolismo , Rúmen/metabolismo , Animais , Proteínas Sanguíneas/análise , Temperatura Corporal , Bovinos/crescimento & desenvolvimento , Bovinos/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Hormônios/sangue , Lipopolissacarídeos/administração & dosagem , Masculino , Distribuição Aleatória
19.
Lett Drug Des Discov ; 6(6): 437, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20119496

RESUMO

AIMS: One promising approach for treatment of Alzheimer's disease (AD) is use of anti-amyloid therapies, based on the hypothesis that increases in amyloid-beta (Aß) deposits in brain are a major cause of AD. Several groups have focused on Aß immunotherapy with some success. Small molecules derivatives of Congo red have been shown to inhibit Aß aggregation and protect against Aß neurotoxicity in vitro. The agents described here are all small molecule Aß-binding agents (SMAßBA's) derivatives of Congo red. MAIN METHODS: Here, we have explored the anti-amyloid properties of these SMAßBA's in mice doubly transgenic for human prensenilin-1 (PS1) and APP gene mutations that cause early-onset AD. Mice were treated with either methoxy-X04, X:EE:B34 and X:034-3-OMe1. After treatment, brains were examined for Aß-deposition, using histochemistry, and soluble and insoluble Aß levels were determined using ELISA. KEY FINDINGS: A range of anti-amyloid activity was observed with these three compounds. PS1/APP mice treated with methoxy-X04 and X:EE:B34 showed decrease in total Aß load, a decrease in Aß fibril load, and a decrease in average plaque size. Treatment with methoxy-X04 also resulted in a decrease in insoluble Aß levels. The structurally similar compound, X:034:3-OMe1, showed no significant effect on any of these measures. The effectiveness of the SMAßBA's may be related to a combination of binding affinity for Aß and entry into brain, but other factors appear to apply as well. SIGNIFICANCE: These data suggest that SMAßBA's may significantly decrease amyloid burden in brain during the pathogenesis of AD and could be useful therapeutics alone, or in combination with immunotherapy.

20.
Neurology ; 71(12): 903-10, 2008 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-18794492

RESUMO

BACKGROUND: Extrapyramidal motor symptoms precede dementia in Parkinson disease (PDD) by many years, whereas dementia occurs early in dementia with Lewy bodies (DLB). Despite this clinical distinction, the neuropsychological and neuropathologic features of these conditions overlap. In addition to widespread distribution of Lewy bodies, both diseases have variable burdens of neuritic plaques and neurofibrillary tangles characteristic of Alzheimer disease (AD). OBJECTIVES: To determine whether amyloid deposition, as assessed by PET imaging with the beta-amyloid-binding compound Pittsburgh Compound B (PiB), can distinguish DLB from PDD, and to assess whether regional patterns of amyloid deposition correlate with specific motor or cognitive features. METHODS: Eight DLB, 7 PDD, 11 Parkinson disease (PD), 15 AD, and 37 normal control (NC) subjects underwent PiB-PET imaging and neuropsychological assessment. Amyloid burden was quantified using the PiB distribution volume ratio. RESULTS: Cortical amyloid burden was higher in the DLB group than in the PDD group, comparable to the AD group. Amyloid deposition in the PDD group was low, comparable to the PD and NC groups. Relative to global cortical retention, occipital PiB retention was lower in the AD group than in the other groups. For the DLB, PDD, and PD groups, amyloid deposition in the parietal (lateral and precuneus)/posterior cingulate region was related to visuospatial impairment. Striatal PiB retention in the DLB and PDD groups was associated with less impaired motor function. CONCLUSIONS: Global cortical amyloid burden is high in dementia with Lewy bodies (DLB) but low in Parkinson disease dementia. These data suggest that beta-amyloid may contribute selectively to the cognitive impairment of DLB and may contribute to the timing of dementia relative to the motor signs of parkinsonism.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Demência/metabolismo , Doença por Corpos de Lewy/psicologia , Doença de Parkinson/psicologia , Tomografia por Emissão de Pósitrons , Idoso , Compostos de Anilina , Encéfalo/diagnóstico por imagem , Cognição , Demência/diagnóstico , Demência/diagnóstico por imagem , Demência/etiologia , Diagnóstico Diferencial , Feminino , Humanos , Doença por Corpos de Lewy/fisiopatologia , Masculino , Pessoa de Meia-Idade , Movimento , Testes Neuropsicológicos , Doença de Parkinson/fisiopatologia , Tiazóis , Distribuição Tecidual
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