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1.
Virchows Arch ; 478(5): 1025-1031, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32676967

RESUMO

Ocular perivascular epithelioid cell tumor (PEComa) is exceedingly rare. We reported two examples involving the choroid and subconjunctival tissue, respectively, in patients aged 17 and 20 years. Both tumors comprised packets and sheets of large polygonal cells with moderately pleomorphic nuclei and prominent nucleoli, traversed by delicate fibrovascular septa. Melanin pigmentation was present in one case. The tumors showed HMB45 and TFE3 immunoreactivity. TFE3 gene translocation was confirmed by FISH break-apart probes. RNA seq revealed PRCC-TFE3 and NONO-TFE3 fusions, with the former representing the first description of PRCC-TFE3 in PEComa. Critical reappraisal of the reported cases showed that ocular PEComa frequently affected young patents with melanin pigmentation, frequent TFE3 protein expression, and/or TFE3 gene translocation. No recurrence or metastasis was reported after complete excision despite the presence of cytologic atypia.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular/genética , Neoplasias da Coroide/genética , Neoplasias Oculares/genética , Fusão Gênica , Doenças do Aparelho Lacrimal/genética , Proteínas de Neoplasias/genética , Neoplasias de Células Epitelioides Perivasculares/genética , Adolescente , Biomarcadores Tumorais/análise , Neoplasias da Coroide/química , Neoplasias da Coroide/patologia , Neoplasias da Coroide/cirurgia , Neoplasias Oculares/química , Neoplasias Oculares/patologia , Neoplasias Oculares/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Doenças do Aparelho Lacrimal/metabolismo , Doenças do Aparelho Lacrimal/patologia , Doenças do Aparelho Lacrimal/cirurgia , Masculino , Melaninas/análise , Neoplasias de Células Epitelioides Perivasculares/química , Neoplasias de Células Epitelioides Perivasculares/patologia , Neoplasias de Células Epitelioides Perivasculares/cirurgia , RNA-Seq , Adulto Jovem
2.
Int J Oral Maxillofac Surg ; 49(3): 333-341, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31353172

RESUMO

Skeletal advancement surgery with sagittal split ramus osteotomy (SSRO) or mandibular distraction osteogenesis (MDO) is effective in treating patients with obstructive sleep apnoea (OSA) and may improve their quality of life (QoL). This study aimed to evaluate the longitudinal QoL changes in moderate-to-severe OSA patients after skeletal advancement surgery. Eighteen patients were randomized to receive SSRO (n=9) or MDO (n=9) alone or as part of the skeletal advancement surgery. Baseline QoL was compared with that of a control group (n=36). QoL was compared between the SSRO group and MDO group over a period of 2 years postoperative. The Epworth Sleepiness Scale (ESS), Calgary Sleep Apnea Quality of Life Index (SAQLI), Functional Outcomes of Sleep Questionnaire (FOSQ), and Short Form Health Survey (SF-36) were used as instruments. The OSA group had worse ESS, SF-36, FOSQ, and SAQLI preoperatively than the control group. The MDO and SSRO groups showed significant improvements in ESS at all postoperative time points (P≤0.021). The FOSQ, SAQLI, and SF-36 of both groups at 2 years postoperative were similar to those of the control group. No differences in QoL were found between the SSRO and MDO groups. This study showed QoL was improved in patients with moderate-to-severe OSA after skeletal advancement surgery by SSRO or MDO.


Assuntos
Avanço Mandibular , Qualidade de Vida , Apneia Obstrutiva do Sono , Humanos , Estudos Longitudinais , Resultado do Tratamento
3.
Org Biomol Chem ; 17(16): 4043-4048, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30950479

RESUMO

Cytochrome c-poly(acrylic acid) (cyt c-PAA) conjugates with 34-fold enchancement in peroxidase turnover number (kcat) are reported. Cyt c-PAA conjugates were prepared by carbodiimide coupling. PAA with molecular weight (Mw) ranging from 1.8k to 250k g mol-1 were employed, and the effect of PAA Mw on peroxiodase kinetics was assessed. The kcat value increased with increased Mw of PAA, ranging from 0.077(±0.002) s-1 in the absence of PAA to 2.66(±0.08) s-1 for the conjugate of cyt c with 250k PAA. Enzymatic activity studies over pH 6-8 indicated improved activity for cyt c-PAA conjugates at neutral or slightly alkaline pH. Examination of the cyt c heme spectroscopy in the presence of H2O2 revealed that formation of compound III, a reactive intermediate that leads to enzyme inactivation, was supressed in cyt c-PAA conjugates. Thus, we suggest the kcat enhancement can be attributed to acidification of the pH microenvironment and inhibition of the formation of a reactive intermediate that deactivates cyt c during the catalytic cycle.


Assuntos
Resinas Acrílicas/metabolismo , Citocromos c/metabolismo , Peroxidases/metabolismo , Resinas Acrílicas/química , Citocromos c/química , Etildimetilaminopropil Carbodi-Imida/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Estrutura Molecular
4.
Hepatology ; 68(1): 113-126, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29360137

RESUMO

Primary liver carcinomas with both hepatocytic and cholangiocytic differentiation have been referred to as "combined (or mixed) hepatocellular-cholangiocarcinoma." These tumors, although described over 100 years ago, have attracted greater attention recently because of interest in possible stem cell origin and perhaps because of greater frequency and clinical recognition. Currently, because of a lack of common terminology in the literature, effective treatment and predictable outcome data have been challenging to accrue. This article represents a consensus document from an international community of pathologists, radiologists, and clinicians who have studied and reported on these tumors and recommends a working terminology for diagnostic and research approaches for further study and evaluation. CONCLUSION: It is recommended that diagnosis is based on routine histopathology with hematoxylin and eosin (H&E); immunostains are supportive, but not essential for diagnosis. (Hepatology 2018;68:113-126).


Assuntos
Carcinoma Hepatocelular/diagnóstico , Colangiocarcinoma/diagnóstico , Neoplasias Hepáticas/classificação , Idoso , Carcinoma Hepatocelular/patologia , Colangiocarcinoma/patologia , Feminino , Humanos , Fígado/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Radiografia , Terminologia como Assunto
5.
Oncogene ; 37(1): 116-127, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28892050

RESUMO

Aberrant protein glycosylation could be a distinct surface-marker of cancer cells that influences cancer progression and metastasis because glycosylation can regulate membrane protein folding which alters receptor activation and changes epitope exposure for antibody (Ab) recognition. Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6), a glycophosphoinositol-anchored protein, is a heavily glycosylated tumor antigen. However, the clinical significance and biological effect of CEACAM6 glycosylation has not been addressed in cancers. We recently developed an anti-CEACAM6 Ab (TMU) from an immune llama library which can be engineered to a single-domain (sd)Ab or a heavy-chain (HC)Ab. The TMU HCAb specifically recognized glycosylated CEACAM6 compared to the conventional antibodies. Using the TMU HCAb, we found that glycosylated CEACAM6 was a tumor marker associated with recurrence in early-stage OSCC (oral squamous cell carcinoma) patients. CEACAM6 promoted OSCC cell invasion, migration, cytoskeletal rearrangement, and metastasis via interaction with epidermal growth factor (EGF) receptor (EGFR) and enhancing EGFR activation, clustering and intracellular signaling cascades. These functions were modulated by N-acetylglucosaminyltransferase 5 (MGAT5) which mediated N-glycosylation at Asn256 (N256) of CEACAM6. Finally, the TMU sdAb and HCAb treatment inhibited the migration, invasion and EGF-induced signaling in CEACAM6-overexpressing cells. In conclusion, the complex N-glycosylation of CEACAM6 is critical for EGFR signaling of OSCC invasion and metastasis. Targeting glycosylated CEACAM6 with the TMU sdAb or TMU HCAb could be a feasible therapy for OSCC.


Assuntos
Antígenos CD/metabolismo , Carcinoma de Células Escamosas/patologia , Moléculas de Adesão Celular/metabolismo , Receptores ErbB/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Bucais/patologia , Recidiva Local de Neoplasia/patologia , Adulto , Animais , Antígenos CD/genética , Asparagina/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/secundário , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Receptores ErbB/genética , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Glicosilação , Humanos , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Camundongos SCID , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Nutr Health Aging ; 19(4): 413-23, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25809805

RESUMO

OBJECTIVES: Epidemiological evidence linking diet, one of the most important modifiable lifestyle factors, and risk of Alzheimer's disease (AD) is rapidly increasing. However, there is little or no evidence for a direct association between dietary nutrients and brain biomarkers of AD. This study identifies nutrient patterns associated with major brain AD biomarkers in a cohort of clinically and cognitively normal (NL) individuals at risk for AD. DESIGN: Cross-sectional study. SETTING: Manhattan (broader area). PARTICIPANTS: Fifty-two NL individuals (age 54+12 y, 70% women, Clinical Dementia Rating=0, MMSE>27, neuropsychological test performance within norms by age and education) with complete dietary information and cross-sectional, 3D T1-weighted Magnetic Resonance Imaging (MRI; gray matter volumes, GMV, a marker of brain atrophy), 11C-Pittsburgh compound-B (PiB; a marker of fibrillar amyloid-ß, Aß) and 18F-fluorodeoxyglucose (FDG; a marker of glucose metabolism, METglc) Positron Emission Tomography (PET) scans were examined. MEASUREMENTS: Dietary intake of 35 nutrients associated with cognitive function and AD was assessed using the Harvard/Willet Food Frequency Questionnaire. Principal component analysis was used to generate nutrient patterns (NP) from the full nutrient panel. Statistical parametric mapping and voxel based morphometry were used to assess the associations of the identified NPs with AD biomarkers. RESULTS: None of the participants were diabetics, smokers, or met criteria for obesity. Five NPs were identified: NP1 was characterized by most B-vitamins and several minerals [VitB and Minerals]; NP2 by monounsaturated and polyunsaturated fats, including ω-3 and ω-6 PUFA, and vitamin E [VitE and PUFA]; NP3 by vitamin A, vitamin C, carotenoids and dietary fibers [Anti-oxidants and Fibers]; NP4 by vitamin B12, vitamin D and zinc [VitB12 and D]; NP5 by saturated, trans-saturated fats, cholesterol and sodium [Fats]. Voxel-based analysis showed that NP4 scores [VitB12 and D] were positively associated with METglc and GMV, and negatively associated with PiB retention in AD-vulnerable regions (p<0.001). In addition, both METglc and GMV were positively associated with NP2 scores [VitE and PUFA], and negatively associated with NP5 scores [Fats] (p<0.001), and METglc was positively associated with higher NP3 scores [Anti-oxidants and Fibers] (p<0.001). Adjusting for age, gender, ethnicity, education, caloric intake, BMI, alcohol consumption, family history and Apolipoprotein E (APOE) status did not attenuate these relationships. The identified 'AD-protective' nutrient combination was associated with higher intake of fresh fruit and vegetables, whole grains, fish and low-fat dairies, and lower intake of sweets, fried potatoes, high-fat dairies, processed meat and butter. CONCLUSION: Specific dietary NPs are associated with brain biomarkers of AD in NL individuals, suggesting that dietary interventions may play a role in the prevention of AD by modulating AD-risk through its effects on Aß and associated neuronal impairment.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Biomarcadores/análise , Encéfalo/metabolismo , Cognição/fisiologia , Dieta/estatística & dados numéricos , Adulto , Idoso , Doença de Alzheimer/patologia , Doença de Alzheimer/psicologia , Amiloide/análise , Encéfalo/patologia , Estudos de Coortes , Estudos Transversais , Feminino , Glucose/metabolismo , Substância Cinzenta , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Cidade de Nova Iorque , Tomografia por Emissão de Pósitrons , Análise de Componente Principal , Inquéritos e Questionários
7.
J Prev Alzheimers Dis ; 1(1): 23-32, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25237654

RESUMO

OBJECTIVES: Epidemiological evidence linking diet, one of the most important modifiable environmental factors, and risk of Alzheimer's disease (AD) is rapidly increasing. Several studies have shown that higher adherence to a Mediterranean diet (MeDi) is associated with reduced risk of AD. This study examines the associations between high vs. lower adherence to a MeDi and structural MRI-based brain atrophy in key regions for AD in cognitively normal (NL) individuals with and without risk factors for AD. DESIGN: Cross-sectional study. SETTING: Manhattan (broader area). PARTICIPANTS: Fifty-two NL individuals (age 54+12 y, 70% women) with complete dietary information and cross-sectional, 3D T1-weighted MRI scans were examined. MEASUREMENTS: Subjects were dichotomized into those showing higher vs. lower adherences to the MeDi using published protocols. Estimates of cortical thickness for entorhinal cortex (EC), inferior parietal lobe, middle temporal gyrus, orbitofrontal cortex (OFC) and posterior cingulate cortex (PCC) were obtained by use of automated segmentation tools (FreeSurfer). Multivariate general linear models and linear regressions assessed the associations of MeDi with MRI measures. RESULTS: Of the 52 participants, 20 (39%) showed higher MeDi adherence (MeDi+) and 32 (61%) showed lower adherence (MeDi-). Groups were comparable for clinical, neuropsychological measures, presence of a family history of AD (FH), and frequency of Apolipoprotein E (APOE) ε4 genotype. With and without controlling for age and total intracranial volume, MeDi+ subjects showed greater thickness of AD-vulnerable ROIs as compared to MeDi- subjects (Wilk's Lambda p=0.026). Group differences were most pronounced in OFC (p=0.001), EC (p=0.03) and PCC (p=0.04) of the left hemisphere. Adjusting for gender, education, FH, APOE status, BMI, insulin resistance scores and presence of hypertension did not attenuate the relationship. CONCLUSION: NL individuals showing lower adherence to the MeDi had cortical thinning in the same brain regions as clinical AD patients compared to those showing higher adherence. These data indicate that the MeDi may have a protective effect against tissue loss, and suggest that dietary interventions may play a role in the prevention of AD.

8.
Neuroimage ; 100: 684-691, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24999038

RESUMO

Interstitial concentration of amyloid beta (Aß) is positively related to synaptic activity in animal experiments. In humans, Aß deposition in Alzheimer's disease overlaps with cortical regions highly active earlier in life. White matter lesions (WML) disrupt connections between gray matter (GM) regions which in turn changes their activation patterns. Here, we tested if WML are related to Aß accumulation (measured with PiB-PET) and glucose uptake (measured with FDG-PET) in connected GM. WML masks from 72 cognitively normal (age 61.7 ± 9.6 years, 71% women) individuals were obtained from T2-FLAIR. MRI and PET images were normalized into common space, segmented and parcellated into gray matter (GM) regions. The effects of WML on connected GM regions were assessed using the Change in Connectivity (ChaCo) score. Defined for each GM region, ChaCo is the percentage of WM tracts connecting to that region that pass through the WML mask. The regional relationship between ChaCo, glucose uptake and Aß was explored via linear regression. Subcortical regions of the bilateral caudate, putamen, calcarine, insula, thalamus and anterior cingulum had WM connections with the most lesions, followed by frontal, occipital, temporal, parietal and cerebellar regions. Regional analysis revealed that GM with more lesions in connecting WM and thus impaired connectivity had lower FDG-PET (r = 0.20, p<0.05 corrected) and lower PiB uptake (r = 0.28, p<0.05 corrected). Regional regression also revealed that both ChaCo (ß = 0.045) and FDG-PET (ß = 0.089) were significant predictors of PiB. In conclusion, brain regions with more lesions in connecting WM had lower glucose metabolism and lower Aß deposition.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Glicemia/metabolismo , Encéfalo/metabolismo , Substância Branca/metabolismo , Idoso , Compostos de Anilina , Encéfalo/patologia , Feminino , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Tiazóis , Substância Branca/patologia
9.
Int J Oral Maxillofac Surg ; 41(11): 1427-38, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22704592

RESUMO

This systematic review was performed to investigate the usefulness and clinical effectiveness of skeletal anchorage devices to determine the most effective bone anchor system for orthodontic tooth movement. Literature on bone anchorage devices was selected from PubMed and the Cochrane Library from January 1966 to June 2010. 55 publications regarding miniplates, miniscrews, palatal implants and dental implants as orthodontic anchorage were identified for further analysis. All bone anchorage devices were found to have relatively high success rates and demonstrated their ability to provide absolute anchorage for orthodontic tooth movement. Significant tooth movement could be achieved with low morbidities and good patient acceptance. The reported success rates for the four groups of anchorage systems were generally high with slight variability (miniplates 91.4-100%; palatal implants 74-93.3%; miniscrews 61-100%; dental implants 100%). It was concluded that bone anchorage systems can achieve effective orthodontic movement with low morbidities. The success rate is generally high with slight variability between miniplates, palatal implants, miniscrews and dental implants. Owing to the lack of randomized controlled trials, there is no strong evidence to confirm which bone anchor system is the most effective for orthodontic tooth movement.


Assuntos
Procedimentos de Ancoragem Ortodôntica/instrumentação , Placas Ósseas , Parafusos Ósseos , Implantes Dentários , Humanos
10.
AJNR Am J Neuroradiol ; 32(11): 2037-42, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21960489

RESUMO

BACKGROUND AND PURPOSE: Emerging evidence suggests that obese adolescents show changes in brain structure compared with lean adolescents. In addition, obesity impacts body development during adolescence. We tested a hypothesis that T1, a marker of brain maturation, can show brain differences associated with obesity. MATERIALS AND METHODS: Adolescents similar in sex, family income, and school grade were recruited by using strict entry criteria. We measured brain T1 in 48 obese and 31 lean adolescents by quantitative MR imaging at 1.5T. We combined MPRAGE and inversion-recovery sequences with normalization to standard space and automated skull stripping to obtain T1 maps with a symmetric voxel volume of 1 mm(3). RESULTS: Sex, income, triglycerides, total cholesterol, and fasting glucose did not differ between groups, but obese adolescents had significantly lower HDL, higher LDL, and higher fasting insulin levels than lean adolescents. Intracranial vault volume did not differ between groups, but obese adolescents had smaller intracranial vault-adjusted brain parenchymal volumes. Obese adolescents had 4 clusters (>100 contiguous voxels) of T1 relaxation that were significantly different (P < .005) from those in lean adolescents. Three of these clusters had longer T1s in obese adolescents (in the orbitofrontal and parietal regions), and 1 cluster had shorter T1s, compared with lean adolescents. CONCLUSIONS: Our results suggest that obesity may have a significant impact on brain development, especially in the frontal and parietal lobes. It is unclear if these changes persist into adulthood or whether they indicate that obese subjects follow a different developmental trajectory during adolescence.


Assuntos
Encéfalo/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Obesidade/patologia , Magreza/patologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
11.
Hong Kong Med J ; 17(1): 39-46, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21282825

RESUMO

OBJECTIVE: To present Hong Kong'Äìspecific data from a large Asian population (also involving Thailand, Singapore, and Taiwan) on safety and manufacturing consistency across four AS03(A)-adjuvanted H5N1 vaccine formulations in terms of immune response against the A/Vietnam/1194/2004 strain. Immunogenicity against the heterologous A/Indonesia/05/2005 strain was also assessed. NCT Number: 00449670. DESIGN: Prospective, observer-blind study. SETTING: Out-patient clinic of a tertiary hospital in Hong Kong. PARTICIPANTS: A total of 360 subjects aged 18 to 60 years were randomised into six groups to receive two doses (21 days apart) of the study vaccine. INTERVENTIONS: One of the four adjuvanted formulations (3.75 microgram H5N1 haemagglutinin [HA]+AS03(A)) of the vaccine (H5N1-AS03(A)) or one of the two non-adjuvanted (3.75 microgram H5N1 [HA]) formulations of the vaccine (H5N1-DIL). MAIN OUTCOME MEASURES: Blood samples collected before vaccination and 21 days after each vaccine dose were analysed using haemagglutination-inhibition and neutralisation assays. Solicited, unsolicited, and serious adverse events were recorded. RESULTS: Manufacturing consistency across all four vaccine formulations was demonstrated. After two doses, the AS03(A)-adjuvanted prepandemic influenza vaccine demonstrated high seroprotection rates against the A/Vietnam/1194/2004 strain (95.8%) and good immunogenicity against the heterologous A/Indonesia/05/2005 strain (45.7%), as compared to the non-adjuvanted vaccine (4.6% and 1.5%, respectively). The seroconversion rates induced by the adjuvanted formulations in terms of viral neutralising antibodies against the two strains were much higher than those induced by the non-adjuvanted formulations. There were no safety concerns for any of the adjuvanted vaccine formulations. CONCLUSIONS: The AS03(A)-adjuvanted H5N1 prepandemic influenza vaccine demonstrated good immunogenicity and an acceptable safety profile in Hong Kong.


Assuntos
Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Adulto , Anticorpos Antivirais/sangue , Feminino , Hong Kong , Humanos , Vacinas contra Influenza/efeitos adversos , Masculino , Pandemias , Estudos Prospectivos
12.
Diabetologia ; 53(11): 2298-306, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20668831

RESUMO

AIMS/HYPOTHESIS: Central nervous system abnormalities, including cognitive and brain impairments, have been documented in adults with type 2 diabetes who also have multiple co-morbid disorders that could contribute to these observations. Assessing adolescents with type 2 diabetes will allow the evaluation of whether diabetes per se may adversely affect brain function and structure years before clinically significant vascular disease develops. METHODS: Eighteen obese adolescents with type 2 diabetes and 18 obese controls without evidence of marked insulin resistance, matched on age, sex, school grade, ethnicity, socioeconomic status, body mass index and waist circumference, completed MRI and neuropsychological evaluations. RESULTS: Adolescents with type 2 diabetes performed consistently worse in all cognitive domains assessed, with the difference reaching statistical significance for estimated intellectual functioning, verbal memory and psychomotor efficiency. There were statistical trends for executive function, reading and spelling. MRI-based automated brain structural analyses revealed both reduced white matter volume and enlarged cerebrospinal fluid space in the whole brain and the frontal lobe in particular, but there was no obvious grey matter volume reduction. In addition, assessments using diffusion tensor imaging revealed reduced white and grey matter microstructural integrity. CONCLUSIONS/INTERPRETATION: This is the first report documenting possible brain abnormalities among obese adolescents with type 2 diabetes relative to obese adolescent controls. These abnormalities are not likely to result from education or socioeconomic bias and may result from a combination of subtle vascular changes, glucose and lipid metabolism abnormalities and subtle differences in adiposity in the absence of clinically significant vascular disease. Future efforts are needed to elucidate the underlying pathophysiological mechanisms.


Assuntos
Encéfalo/patologia , Diabetes Mellitus Tipo 2/complicações , Obesidade/complicações , Adolescente , Índice de Massa Corporal , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Circunferência da Cintura
13.
Neurology ; 72(6): 513-20, 2009 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19005175

RESUMO

BACKGROUND: At cross-section, cognitively normal individuals (NL) with a maternal history of late-onset Alzheimer disease (AD) have reduced glucose metabolism (CMRglc) on FDG-PET in the same brain regions as patients with clinical AD as compared to those with a paternal and a negative family history (FH) of AD. This longitudinal FDG-PET study examines whether CMRglc reductions in NL subjects with a maternal history of AD are progressive. METHODS: Seventy-five 50- to 82-year-old NL received 2-year follow-up clinical, neuropsychological, and FDG-PET examinations. These included 37 subjects with negative family history of AD (FH-), 9 with paternal (FHp), and 20 with maternal AD (FHm). Two subjects had parents with postmortem confirmed AD. Statistical parametric mapping was used to compare CMRglc across FH groups at baseline, follow-up, and longitudinally. RESULTS: At both time points, the FH groups were comparable for demographic and neuropsychological characteristics. At baseline and at follow-up, FHm subjects showed CMRglc reductions in the parieto-temporal, posterior cingulate, and medial temporal cortices as compared to FH- and FHp (p < 0.001). Longitudinally, FHm had significant CMRglc declines in these regions, which were significantly greater than those in FH- and FHp (p < 0.05). CONCLUSIONS: A maternal history of Alzheimer disease (AD) predisposes normal individuals to progressive CMRglc reductions in AD-vulnerable brain regions, which may be related to a higher risk for developing AD.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/congênito , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Glucose/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença/genética , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Mães
14.
J Neurol ; 254(12): 1666-75, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17994313

RESUMO

Very little data exist to evaluate the value of longitudinal CSF biological markers for Alzheimer's disease (AD). Most studies indicate that tau and amyloid beta markers do not reflect disease progression. We now report on a longitudinal, three-time point, CSF Isoprostane (IsoP) and quantitative MRI study that examined 11 normal elderly (NL) volunteers and 6 Mild Cognitive Impairment (MCI) patients. After 4 years, all 6 MCI patients declined to AD and 2 of the NL subjects declined to MCI. At baseline and longitudinally, the MCI patients showed reduced delayed memory, increased IsoP levels, and reduced medial temporal lobe gray matter concentrations as compared to NL. A group comprised of all decliners to AD or to MCI (n = 8) was distinguished at baseline from the stable NL controls (n = 9) by IsoP with 100% accuracy.Moreover, both at baseline and longitudinally, the IsoP measures significantly improved the diagnostic and predictive outcomes of conventional memory testing and quantitative MRI measurements. These data indicate that IsoP is potentially useful for both the early detection of AD-related pathology and for monitoring the course of AD.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/patologia , Isoprostanos/líquido cefalorraquidiano , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Atrofia , Mapeamento Encefálico , Transtornos Cognitivos/líquido cefalorraquidiano , Transtornos Cognitivos/patologia , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Valor Preditivo dos Testes
15.
Ann N Y Acad Sci ; 1097: 114-45, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17413016

RESUMO

It is widely believed that the path to early and effective treatment for Alzheimer's disease (AD) requires the development of early diagnostic markers that are both sensitive and specific. To this aim, using longitudinal study designs, we and others have examined magnetic resonance imaging (MRI), 2-fluoro-2-deoxy-d-glucose-positron emission tomography (FDG/PET), and cerebrospinal fluid (CSF) biomarkers in cognitively normal elderly (NL) subjects and in patients with mild cognitive impairment (MCI). Such investigations have led to the often replicated findings that structural evidence of hippocampal atrophy as determined by MRI, as well as metabolic evidence from FDG-PET scan of hippocampal damage, predicts the conversion from MCI to AD. In this article we present a growing body of evidence of even earlier diagnosis. Brain pathology can be detected in NL subjects and used to predict future transition to MCI. This prediction is enabled by examinations revealing reduced glucose metabolism in the hippocampal formation (hippocampus and entorhinal cortex [EC]) as well as by the rate of medial temporal lobe atrophy as determined by MRI. However, neither regional atrophy nor glucose metabolism reductions are specific for AD. These measures provide secondary not primary evidence for AD. Consequently, we will also summarize recent efforts to improve the diagnostic specificity by combining imaging with CSF biomarkers and most recently by evaluating amyloid imaging using PET. We conclude that the combined use of conventional imaging, that is MRI or FDG-PET, with selected CSF biomarkers incrementally contributes to the early and specific diagnosis of AD. Moreover, selected combinations of imaging and CSF biomarkers measures are of importance in monitoring the course of AD and thus relevant to evaluating clinical trials.


Assuntos
Envelhecimento/genética , Envelhecimento/patologia , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Genômica , Doença de Alzheimer/epidemiologia , Animais , Apolipoproteínas E/genética , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/patologia , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Fatores de Risco
16.
Diabetologia ; 50(4): 711-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17334649

RESUMO

AIMS/HYPOTHESIS: There is evidence that type 2 diabetes mellitus is associated with cognitive impairment. Most studies investigating this association have evaluated elderly individuals, after many years of diabetes, who generally have poor glycaemic control and significant vascular disease. The aim of the current study was to investigate the early cognitive consequences and associated brain correlates of type 2 diabetes. MATERIALS AND METHODS: With regard to cognition and brain measures, we compared 23 age-, sex- and education-matched control subjects with 23 mostly middle-aged individuals with relatively well-controlled diabetes of less than 10 years from the time of diagnosis. RESULTS: We found deficits in hippocampal-based memory performance and preservation of other cognitive domains. Relative to control subjects, individuals with diabetes had reductions in brain volumes that were restricted to the hippocampus. There was an inverse relationship between glycaemic control and hippocampal volume; in multivariate regression analysis, HbA(1c) was the only significant predictor of hippocampal volume, accounting for 33% of the observed variance. Other variables commonly associated with type 2 diabetes, such as elevated BMI, hypertension or dyslipidaemia, did not independently contribute to the variance in hippocampal volume. CONCLUSIONS/INTERPRETATION: These results suggest that the medial temporal lobe may be the first brain site affected by type 2 diabetes and that individuals in poorer metabolic control may be affected to a greater extent.


Assuntos
Encefalopatias/complicações , Complicações do Diabetes/diagnóstico , Diabetes Mellitus Tipo 2/patologia , Hipocampo/patologia , Transtornos da Memória/complicações , Idoso , Encéfalo/patologia , Cognição , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
17.
AJNR Am J Neuroradiol ; 28(1): 135-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17213441

RESUMO

Inflammatory myofibroblastic tumor (IMT) is a rare tumor with a variable natural history and biologic behavior, ranging from completely benign to malignant with fatal outcome. We report a case of benign IMT in the left nasal cavity with radiologic features mimicking angiofibroma. We also demonstrate the hypervascular nature of this disease on angiography and the contribution of preoperative embolization in assisting surgical excision and minimizing the potential uncontrolled intraoperative bleeding.


Assuntos
Angiografia , Cavidade Nasal , Neoplasias de Tecido Muscular/diagnóstico , Neoplasias Nasais/diagnóstico , Adolescente , Terapia Combinada , Diagnóstico Diferencial , Embolização Terapêutica , Feminino , Humanos , Inflamação/patologia , Artéria Maxilar/diagnóstico por imagem , Cavidade Nasal/irrigação sanguínea , Cavidade Nasal/patologia , Cavidade Nasal/cirurgia , Terapia Neoadjuvante , Neoplasias de Tecido Muscular/irrigação sanguínea , Neoplasias de Tecido Muscular/patologia , Neoplasias de Tecido Muscular/cirurgia , Neoplasias Nasais/irrigação sanguínea , Neoplasias Nasais/patologia , Neoplasias Nasais/cirurgia
18.
Vaccine ; 24(25): 5371-80, 2006 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-16713661

RESUMO

We investigated the immune antibody response to influenza vaccine in community-dwelling Chinese elderly persons in Hong Kong. One hundred and twenty-eight subjects were recruited in a single-blind, randomized, and placebo-controlled trial. There was no significant baseline difference between the vaccine and placebo groups regarding the seroprotection rates (PR) (haemagglutination inhibition [HI] titre>or=1:40) and geometric mean titres (GMT) of the HI antibody titers. The PR, GMTs and serological response rates increased significantly in the vaccinated versus placebo groups in A-H1N1 at both weeks 4 and month 6. The GMTs and serological response rates but not the PR for A-H3N2 and influenza B increased significantly in vaccinated versus placebo group at week 4 and month 6 post-vaccination. Multivariate logistic regression analyses of the seroconversion rate for A-H3N2 within the vaccinated group showed that gender, coronary heart disease and the serum albumin level were significant predictors (p=0.018, 0.009 and 0.025, respectively). Influenza vaccination provoked a protective HI antibody response in community-living Chinese elderly persons. The mean number of unplanned hospital admissions per subject over 6 months was significantly lower in the vaccinated than in the placebo groups. Hospitalized elderly persons had poorer nutrition, 4-week post-immunization HI antibody titres and lower mini-mental state examination (MMSE) score than non-hospitalized elderly persons. Logistic regression analyses showed that chronic obstructive airway disease significantly increased the risk of hospitalization while the serum albumin level and 4-week A-H3N2 PR (HI>or=40) were independent predictors of a decreased risk of hospitalizations.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/administração & dosagem , Características de Residência , Idoso , Idoso de 80 Anos ou mais , Feminino , Testes de Inibição da Hemaglutinação , Hong Kong , Humanos , Esquemas de Imunização , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Masculino , Vacinação
19.
Neurobiol Aging ; 27(3): 394-401, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16125823

RESUMO

The diagnosis of Alzheimer's disease (AD) in patients with mild cognitive impairment (MCI) is limited because it is based on non-specific behavioral and neuroimaging findings. The lesions of Alzheimer's disease: amyloid beta (Abeta) deposits, tau pathology and cellular oxidative damage, affect the hippocampus in the earlier stages causing memory impairment. In a 2-year longitudinal study of MCI patients and normal controls, we examined the hypothesis that cerebrospinal fluid (CSF) markers for these pathological features improve the diagnostic accuracy over memory and magnetic resonance imaging (MRI)-hippocampal volume evaluations. Relative to control, MCI patients showed decreased memory and hippocampal volumes and elevated CSF levels of hyperphosphorylated tau and isoprostane. These two CSF measures consistently improved the diagnostic accuracy over the memory measures and the isoprostane measure incremented the accuracy of the hippocampal volume achieving overall diagnostic accuracies of about 90%. Among MCI patients, over 2 years, longitudinal hippocampal volume losses were closely associated with increasing hyperphosphorylated tau and decreasing amyloid beta-42 levels. These results demonstrate that CSF biomarkers for AD contribute to the characterization of MCI.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Transtornos Cognitivos/diagnóstico , Hipocampo/patologia , Isoprostanos/líquido cefalorraquidiano , Imageamento por Ressonância Magnética/métodos , Proteínas tau/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/complicações , Biomarcadores/líquido cefalorraquidiano , Transtornos Cognitivos/líquido cefalorraquidiano , Transtornos Cognitivos/etiologia , Feminino , Humanos , Aumento da Imagem/métodos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Neurology ; 64(11): 1860-7, 2005 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-15955934

RESUMO

BACKGROUND: To facilitate image analysis, most recent 2-[18F]fluoro-2-deoxy-d-glucose PET (FDG-PET) studies of glucose metabolism (MRglc) have used automated voxel-based analysis (VBA) procedures but paradoxically none reports hippocampus MRglc reductions in mild cognitive impairment (MCI) or Alzheimer disease (AD). Only a few studies, those using regions of interest (ROIs), report hippocampal reductions. The authors created an automated and anatomically valid mask technique to sample the hippocampus on PET (HipMask). METHODS: Hippocampal ROIs drawn on the MRI of 48 subjects (20 healthy elderly [NL], 16 MCI, and 12 AD) were used to develop the HipMask. The HipMask technique was applied in an FDG-PET study of NL (n = 11), MCI (n = 13), and AD (n = 12), and compared to both MRI-guided ROIs and VBA methods. RESULTS: HipMask and ROI hippocampal sampling produced significant and equivalent MRglc reductions for contrasts between MCI and AD relative to NL. The VBA showed typical cortical effects but failed to show hippocampal MRglc reductions in either clinical group. Hippocampal MRglc was the only discriminator of NL vs MCI (78% accuracy) and added to the cortical MRglc in classifying NL vs AD and MCI vs AD. CONCLUSIONS: The new HipMask technique provides accurate and rapid assessment of the hippocampus on PET without the use of regions of interest. Hippocampal glucose metabolism reductions are found in both mild cognitive impairment and Alzheimer disease and contribute to their diagnostic classification. These results suggest re-examination of prior voxel-based analysis 2-[18F]fluoro-2-deoxy-d-glucose PET studies that failed to report hippocampal effects.


Assuntos
Doença de Alzheimer/diagnóstico , Transtornos Cognitivos/diagnóstico , Fluordesoxiglucose F18 , Hipocampo/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/metabolismo , Estudos de Coortes , Regulação para Baixo/fisiologia , Metabolismo Energético/fisiologia , Feminino , Glucose/metabolismo , Hipocampo/diagnóstico por imagem , Hipocampo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Design de Software
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