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1.
AJNR Am J Neuroradiol ; 44(4): 417-423, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36927761

RESUMO

BACKGROUND AND PURPOSE: Incidental findings are discovered in neuroimaging research, ranging from trivial to life-threatening. We describe the prevalence and characteristics of incidental findings from 16,400 research brain MRIs, comparing spontaneous detection by nonradiology scanning staff versus formal neuroradiologist interpretation. MATERIALS AND METHODS: We prospectively collected 16,400 brain MRIs (7782 males, 8618 females; younger than 1 to 94 years of age; median age, 38 years) under an institutional review board directive intended to identify clinically relevant incidental findings. The study population included 13,150 presumed healthy volunteers and 3250 individuals with known neurologic diagnoses. Scanning staff were asked to flag concerning imaging findings seen during the scan session, and neuroradiologists produced structured reports after reviewing every scan. RESULTS: Neuroradiologists reported 13,593/16,400 (83%) scans as having normal findings, 2193/16,400 (13.3%) with abnormal findings without follow-up recommended, and 614/16,400 (3.7%) with "abnormal findings with follow-up recommended." The most common abnormalities prompting follow-up were vascular (263/614, 43%), neoplastic (130/614, 21%), and congenital (92/614, 15%). Volunteers older than 65 years of age were significantly more likely to have scans with abnormal findings (P < .001); however, among all volunteers with incidental findings, those younger than 65 years of age were more likely to be recommended for follow-up. Nonradiologists flagged <1% of MRIs containing at least 1 abnormality reported by the neuroradiologists to be concerning enough to warrant further evaluation. CONCLUSIONS: Four percent of individuals who undergo research brain MRIs have an incidental, potentially clinically significant finding. Routine neuroradiologist review of all scans yields a much higher rate of significant lesion detection than selective referral from nonradiologists who perform the examinations. Workflow and scan review processes need to be carefully considered when designing research protocols.


Assuntos
Encefalopatias , Encéfalo , Masculino , Feminino , Humanos , Adulto , Encéfalo/patologia , Encefalopatias/diagnóstico por imagem , Encefalopatias/epidemiologia , Achados Incidentais , Imageamento por Ressonância Magnética , Neuroimagem , Voluntários
2.
Neurology ; 78(22): 1769-76, 2012 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-22592366

RESUMO

OBJECTIVE: To evaluate the longitudinal influence of family history (FH) of Alzheimer disease (AD) and apolipoprotein E ε4 allele (APOE4) on brain atrophy and cognitive decline over 4 years among asymptomatic middle-aged individuals. METHODS: Participants were cognitively healthy adults with (FH+) (n = 60) and without (FH-) (n = 48) a FH of AD (mean age at baseline 54 years) enrolled in the Wisconsin Registry for Alzheimer's Prevention. They underwent APOE genotyping, cognitive testing, and an MRI scan at baseline and 4 years later. A covariate-adjusted voxel-based analysis interrogated gray matter (GM) modulated probability maps at the 4-year follow-up visit as a function of FH and APOE4. We also examined the influence of parent of origin on GM atrophy. Parallel analyses investigated the effects of FH and APOE4 on cognitive decline. RESULTS: Neither FH nor APOE4 had an effect on regional GM or cognition at baseline. Longitudinally, a FH × APOE4 interaction was found in the right posterior hippocampus, which was driven by a significant difference between the FH+ and FH- subjects who were APOE4-. In addition, a significant FH main effect was observed in the left posterior hippocampus. No significant APOE4 main effects were detected. Persons with a maternal history of AD were just as likely as those with a paternal history of AD to experience posterior hippocampal atrophy. There was no longitudinal decline in cognition within the cohort. CONCLUSION: Over a 4-year interval, asymptomatic middle-aged adults with FH of AD exhibit significant atrophy in the posterior hippocampi in the absence of measurable cognitive changes. This result provides further evidence that detectable disease-related neuroanatomic changes do occur early in the AD pathologic cascade.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Hipocampo/patologia , Doença de Alzheimer/prevenção & controle , Análise de Variância , Atrofia/diagnóstico , Cognição , Estudos de Coortes , Pai , Feminino , Genótipo , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Anamnese , Pessoa de Meia-Idade , Mães , Testes Neuropsicológicos , Valor Preditivo dos Testes
3.
Eur J Cancer Care (Engl) ; 20(4): 445-54, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20738392

RESUMO

Clinical trials are crucial to improve cancer treatment but recruitment is difficult. Optimised patient information has been recognised as a key issue. In line with the increasing focus on patients' perspectives in health care, we aimed to study patients' opinions about the written information used in three clinical trials for breast cancer. Primary data collection was done in focus group interviews with breast cancer patient advocates. Content analysis identified three major themes: comprehensibility, emotions and associations, and decision making. Based on the advocates' suggestions for improvements, 21 key issues were defined and validated through a questionnaire in an independent group of breast cancer patient advocates. Clear messages, emotionally neutral expressions, careful descriptions of side effects, clear comparisons between different treatment alternatives and information about the possibility to discontinue treatment were perceived as the most important issues. Patients' views of the information in clinical trials provide new insights and identify key issues to consider in optimising future written information and may improve recruitment to clinical cancer trials.


Assuntos
Neoplasias da Mama , Ensaios Clínicos como Assunto , Consentimento Livre e Esclarecido/normas , Educação de Pacientes como Assunto , Idoso , Neoplasias da Mama/psicologia , Comunicação , Feminino , Grupos Focais , Humanos , Consentimento Livre e Esclarecido/psicologia , Pessoa de Meia-Idade , Defesa do Paciente , Pesquisa Qualitativa , Inquéritos e Questionários
4.
J Eur Acad Dermatol Venereol ; 24(9): 1013-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20337812

RESUMO

Itch accompanies most inflammatory skin diseases but may occur as a solitary sensation in otherwise normal skin. Chronic itch often requires combined treatments but some cases remain therapy resistant. Complementary medicine is becoming increasingly popular among patients. Acupuncture is the oldest and most well-studied alternative option with evidence-based effect on pain. This article summarizes the rational for the use of acupuncture in treatment of itch and reviews therapeutic and experimental therapeutic studies on acupuncture and itch.


Assuntos
Acupuntura , Prurido/terapia , Dermatopatias/terapia , Humanos
5.
Water Res ; 44(9): 2850-62, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20188390

RESUMO

Biocides and pesticides are designed to control the occurrence of unwanted organisms. From their point of application, these substances can be mobilized and transported to surface waters posing a threat to the aquatic environment. Historically, agricultural pesticides have received substantially more attention than biocidal compounds from urban use, despite being used in similar quantities. This study aims at improving our understanding of the influence of mixed urban and agricultural land use on the overall concentration dynamics of biocides and pesticides during rain events throughout the year. A comprehensive field study was conducted in a catchment within the Swiss plateau (25 km(2)). Four surface water sampling sites represented varying combinations of urban and agricultural sources. Additionally, the urban drainage system was studied by sampling the only wastewater treatment plant (WWTP) in the catchment, a combined sewer overflow (CSO), and a storm sewer (SS). High temporal resolution sampling was carried out during rain events from March to November 2007. The results, based on more than 600 samples analyzed for 23 substances, revealed distinct and complex concentration patterns for different compounds and sources. Five types of concentration patterns can be distinguished: a) compounds that showed elevated background concentrations throughout the year (e.g. diazinon >50 ng L(-1)), indicating a constant household source; b) compounds that showed elevated concentrations driven by rain events throughout the year (e.g. diuron 100-300 ng L(-1)), indicating a constant urban outdoor source such as facades; c) compounds with seasonal peak concentrations driven by rain events from urban and agricultural areas (e.g. mecoprop 1600 ng L(-1) and atrazine 2500 ng L(-1) respectively); d) compounds that showed unpredictably sharp peaks (e.g. atrazine 10,000 ng L(-1), diazinon 2500 ng L(-1)), which were most probably due to improper handling or even disposal of products; and finally, e) compounds that were used in high amounts but were not detected in surface waters (e.g. isothiazolinones). It can be safely concluded that in catchments of mixed land use, the contributions of biocide and pesticide inputs into surface waters from urban areas are at least as important as those from agricultural areas.


Assuntos
Agricultura , Desinfetantes/análise , Água Doce/análise , Praguicidas/análise , Reforma Urbana , Monitoramento Ambiental , Chuva , Movimentos da Água , Poluentes Químicos da Água/análise
6.
Maturitas ; 65(2): 131-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20044221

RESUMO

Factors contributing to increased risk for Alzheimer's disease (AD) include age, sex, genes, and family history of AD. Several risk factors for AD are endogenous; however, accumulating evidence implicates modifiable risk factors in the pathogenesis of AD. Although the continued task of identifying new genes will be critical to learning more about the disease, several research findings suggest that potentially alterable environmental factors influence genetic contributions, providing targets for disease prevention and treatment. Here, we review midlife risk factors for AD, and address the potential for therapeutic intervention in midlife.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/genética , Doenças Cardiovasculares/complicações , Feminino , Predisposição Genética para Doença , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Fatores Socioeconômicos
7.
J Vet Intern Med ; 23(5): 1007-13, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19674279

RESUMO

BACKGROUND: The contribution of right heart (RH) chamber enlargement to general heart enlargement seen on thoracic radiographs in mitral regurgitation (MR) is not known. OBJECTIVES: To determine the size and shape of the RH chambers in normal dogs and dogs with varying degrees of MR. ANIMALS: Fifty-four privately owned dogs: 13 normal, 41 with varying degrees of MR including 25 with congestive heart failure (CHF). METHODS: Archived first pass radionuclide angiocardiograms were used to produce static images of the RH and left heart (LH) chambers. Indexes of size and shape of the RH and LH chambers were related to severity of MR determined by heart rate-normalized pulmonary transit time (nPTT), vertebral heart scale (VHS), and clinical status. RH shape was measured by a circularity index of RH short axis/long axis. RESULTS: A 2nd degree polynomial fit best described the ratios; RH/LH dimension to nPTT (R(2)= 0.62) and to VHS (R(2)= 0.43), RH/LH area to nPTT (R(2)= 0.64) and to VHS (R(2)= 0.58), all P < .001. RH circularity was decreased in CHF, P < .001. In CHF, the RH chambers of 16 dogs were both flattened and enlarged, whereas 9 had convex septal borders. CONCLUSIONS: RH chambers are not significantly dilated in dogs with mild to moderate MR without CHF. In CHF, RH chambers enlarge and also may be compressed by the LH chambers. Pulmonary hypertension probably is present in some dogs with CHF. Increased sternal contact is not a useful sign of right-sided heart dilatation in MR.


Assuntos
Cardiomegalia/veterinária , Doenças do Cão/patologia , Insuficiência da Valva Mitral/veterinária , Angiocardiografia/veterinária , Animais , Cardiomegalia/patologia , Cães , Átrios do Coração/patologia , Ventrículos do Coração/patologia , Insuficiência da Valva Mitral/patologia , Análise de Regressão , Estudos Retrospectivos
8.
Rev Sci Instrum ; 80(7): 073108, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19655944

RESUMO

The JILA multidimensional optical nonlinear spectrometer (JILA-MONSTR) is a robust, ultrastable platform consisting of nested and folded Michelson interferometers that can be actively phase stabilized. This platform generates a square of identical laser pulses that can be adjusted to have arbitrary time delay between them while maintaining phase stability. The JILA-MONSTR provides output pulses for nonlinear excitation of materials and phase-stabilized reference pulses for heterodyne detection of the induced signal. This arrangement is ideal for performing coherent optical experiments, such as multidimensional Fourier-transform spectroscopy, which records the phase of the nonlinear signal as a function of the time delay between several of the excitation pulses. The resulting multidimensional spectrum is obtained from a Fourier transform. This spectrum can resolve, separate, and isolate coherent contributions to the light-matter interactions associated with electronic excitation at optical frequencies. To show the versatility of the JILA-MONSTR, several demonstrations of two-dimensional Fourier-transform spectroscopy are presented, including an example of a phase-cycling scheme that reduces noise. Also shown is a spectrum that accesses two-quantum coherences, where all excitation pulses require phase locking for detection of the signal.

9.
Eur J Anaesthesiol ; 25(7): 528-30, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18413009

RESUMO

The expansion of the European Union during the last 2 yr has resulted in the need for a revision of existing guidelines to further harmonize education and training in the specialty of anaesthesiology throughout the European Union. Although each individual country is responsible for its own training and certification, these guidelines are intended to reflect minimum criteria for specialist training. It is the opinion of the Section and Board of Anaesthesia that specialist training will need to be for a minimum of 5 yr.


Assuntos
Anestesia/normas , Anestesiologia/educação , Cuidados Críticos/normas , Conselhos de Especialidade Profissional/normas , Anestesiologia/normas , Certificação/normas , Educação Médica , Avaliação Educacional/normas , União Europeia , Humanos , Medicina/normas , Especialização , Ensino/normas
10.
J Physiol Pharmacol ; 59(1): 115-28, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18441392

RESUMO

With diabetes mellitus, the ability of the kidneys to maintain fluid balance is affected. Hyperglycaemia increases production of hyaluronan in cultured kidney cells implying that diabetes promotes induction of hyaluronan in the kidney. The aim of the present study was to determine if the interstitial matrix component hyaluronan is differently distributed within the kidney in diabetic rats compared to non-diabetic rats. Furthermore, to test if diabetic rats are able to respond with diuresis upon a hypotonic fluid load. The normal heterogeneous intrarenal distribution of hyaluronan was confirmed in non-diabetic control rats, with 60-fold more in the papilla than in the cortex. In diabetic animals, the cortical hyaluronan was unaffected but the papillary hyaluronan content was 3-fold higher than in non-diabetic rats. This increase correlated with a more than three-fold induction of the papillary hyaluronan-synthase 2 mRNA expression. In non-diabetic animals, 2 h water loading increased papillary hyaluronan (+93%) and diuresis (17-fold). In diabetic animals, baseline diuresis was 8-fold higher than in non-diabetic animals, which correlated with hyperglycaemia, glucosuria and proteinuria. Water loading in diabetic animals did not further increase papillary hyaluronan or diuresis: the urine flow rate decreased. To conclude, papillary hyaluronan is elevated in diabetic rats, which coincides with induction of hyaluronan-synthase 2 mRNA, hyperglycaemia, glucosuria, proteinuria and overt diuresis. The inability to respond to a water load with further diuresis may be related to the already elevated papillary hyaluronan and the inability to change hyaluronan during water loading.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Glucuronosiltransferase/metabolismo , Ácido Hialurônico/metabolismo , Animais , Diurese/fisiologia , Expressão Gênica/fisiologia , Glicosúria/fisiopatologia , Hialuronan Sintases , Hiperglicemia/fisiopatologia , Córtex Renal/metabolismo , Medula Renal/metabolismo , Masculino , Proteinúria/fisiopatologia , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos WF
11.
J Genet Couns ; 16(6): 811-20, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17705030

RESUMO

Hereditary non-polyposis colorectal cancer (HNPCC) is one of our most common cancer syndromes and an increasing number of individuals live in families with verified hereditary cancer. We conducted an interview study to explore experiences from and perceived impact on life after genetic testing for HNPCC. Three major themes emerged: reactions and emotions, family relations and implications for life. Among the reactions described were suspecting heredity, feelings of guilt, the importance of experiential knowledge, and coping strategies. The impact on family relations was related to perceived responsibility for conveying information, encountering different reactions among family members, and difficulties in communication and relations. The implications described included uncertainty, adaptation, new choices and changes in life, family planning issues, and experiences of surveillance programs. We suggest that the themes and sub-themes identified should be taken into account during genetic counselling in order to facilitate the spread of information and to prepare family members for the impact on life that knowledge about hereditary cancer may have.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/psicologia , Adaptação Psicológica , Adulto , Idoso , Ansiedade , Portador Sadio , Emoções , Feminino , Aconselhamento Genético , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Mutação
12.
Eur J Anaesthesiol ; 24(7): 563-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17568472

RESUMO

The still ever increasing demand for sedation and/or analgesia for diagnostic and therapeutic procedures puts high pressure on anaesthesia care providers all over Europe. Since the capacity to provide that service by anaesthetists is limited in most European countries, guidelines for non-anaesthetist doctors who want to sedate patients on a high-quality level and especially in a safe way are mandatory. This paper, produced by a working party of the European Board of Anaesthesiology of the European Union of Medical Specialists (EUMS/UEMS), gives direction to those practitioners who feel responsibilities in this area of medicine. Close cooperation with anaesthesiologists seems mandatory to achieve and sustain a high-quality standard for our patients undergoing medical or surgical procedures under sedation.


Assuntos
Analgesia/métodos , Anestesia/métodos , Anestesiologia , Médicos , Sociedades Médicas , Conselhos de Especialidade Profissional , Assistência ao Convalescente , Analgesia/efeitos adversos , Anestesia/efeitos adversos , Período de Recuperação da Anestesia , Anestesiologia/educação , Certificação , Competência Clínica , Educação Médica Continuada , Educação de Pós-Graduação em Medicina , Europa (Continente) , Pessoal de Saúde/educação , Humanos , Prontuários Médicos , Monitorização Fisiológica , Seleção de Pacientes , Garantia da Qualidade dos Cuidados de Saúde , Recursos Humanos
13.
Neurology ; 67(11): 2039-41, 2006 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-17159116

RESUMO

We compared fMRI and cognitive data from nine hormone therapy (HT)-naive women with data from women exposed to either opposed conjugated equine estrogens (CEE) (n = 10) or opposed estradiol (n = 4). Exposure to either form of HT was associated with healthier fMRI response; however, CEE-exposed women exhibited poorer memory performance than either HT-naive or estradiol-exposed subjects. These preliminary findings emphasize the need to characterize differential neural effects of various HTs.


Assuntos
Cognição/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios Conjugados (USP)/farmacologia , Imageamento por Ressonância Magnética , Cognição/fisiologia , Terapia de Reposição de Estrogênios/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Pós-Menopausa/efeitos dos fármacos , Pós-Menopausa/fisiologia
14.
Br J Dermatol ; 155(5): 970-6, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17034527

RESUMO

BACKGROUND: The effect of acupuncture on nociceptive pain is well documented, but effects on nociceptive itch have been contradictory. OBJECTIVES: To evaluate possible effects of acupuncture on the occurrence, distribution and function of sensory nerve fibres in human skin. METHODS: Ten subjects were treated by inserting 10 acupuncture needles subcutaneously at the upper lateral aspect of one buttock. The subjects were recruited from an acupuncture clinic and were undergoing specific acupuncture treatment for their disorders. The needles were stimulated (rotated to and fro) twice during the twice-weekly 25-min sessions over 5 weeks. Skin biopsies, diameter 3 mm, were taken before and 3-6 days after local acupuncture. Antibodies to the pan-neuronal marker protein gene product 9.5 (PGP 9.5), calcitonin gene-related peptide (CGRP), vanilloid receptor 1 (VR1) and mu- and delta-opioid receptors were employed to study sensory unmyelinated nerve fibres that transmit nociceptive pain and itch. A histamine prick test using planimetry was used to record experimental itch after acupuncture on the treated area and on the corresponding control skin, and a visual analogue scale was used to evaluate itch. RESULTS: The mean +/- SEM number of CGRP-immunoreactive nerve fibres per biopsy section was reduced from 36.0 +/- 3.3 to 21.3 +/- 4.0 (P = 0.05) after the treatment. PGP 9.5-immunoreactive nerve fibres were found both in the epidermis and in the subpapillary dermis. The mean +/- SEM total number of PGP 9.5-immunoreactive nerve fibres decreased from 249.8 +/- 16.7 to 211.8 +/- 12.0 (P = 0.03). The PGP 9.5-immunoreactive nerve fibres occurring in the dermis appeared more fragmented after the acupuncture compared with pretreatment. VR1 immunoreactivity was found both in the free nerve fibres and in kite-like formations, possibly mast cells, throughout the dermis, sometimes occurring around hair follicles. The mean +/- SEM number of VR1-immunoreactive elements was not significantly influenced by acupuncture, at 33.5 +/- 4.6 vs. 43.0 +/- 4.4 (P = 0.09). No immunoreactivity was found in the skin against mu- and delta-opioid receptors with the antibodies used in this study. Neither histamine-induced itch nor cutaneous responses were influenced by acupuncture. CONCLUSIONS: The present data indicate an effect of acupuncture on neuropathic itch but not histamine-mediated itch. Our findings support the opinion that the pain-relieving effects of acupuncture partly depend on its effect on the peripheral innervation.


Assuntos
Terapia por Acupuntura/métodos , Pele/inervação , Analgesia por Acupuntura/métodos , Adulto , Idoso , Biópsia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Feminino , Histamina , Humanos , Pessoa de Meia-Idade , Fibras Nervosas/metabolismo , Fibras Nervosas/patologia , Neurônios Aferentes/metabolismo , Neurônios Aferentes/patologia , Prurido/patologia , Prurido/terapia , Pele/patologia , Ubiquitina Tiolesterase/metabolismo
15.
J Chem Phys ; 124(14): 144905, 2006 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-16626243

RESUMO

Three pulse photon echo peak shift spectroscopy and transient grating measurements on Zn-substituted cytochrome c, Zn-tetraphenylporphyrin, and Zn-protoporphyrin IX are reported. The effects of protein conformation, axial ligation, and solvent are investigated. Numerical simulations of the peak shift and transient grating experiments are presented. The simulations employed recently derived optical response functions for square-symmetric molecules with doubly degenerate excited states. Simulations exploring the effects of excited-state energy splitting, symmetric and asymmetric fluctuations, and excited-state lifetime show that the time scales of the peak shift decay in the three-level system largely reflect the same dynamics as in the two-level system. However, the asymptotic peak shift, which is a clear indicator of inhomogeneous broadening in a two-level system, must be interpreted more carefully for three-level systems, as it is also influenced by the magnitude of the excited-state splitting. The calculated signals qualitatively reproduce the data.


Assuntos
Citocromos c/química , Porfirinas/química , Protoporfirinas/química , Espectrofotometria/métodos , Zinco/química , Animais , Fenômenos Químicos , Físico-Química , Heme/química , Cavalos , Modelos Estatísticos , Modelos Teóricos , Oscilometria , Solventes
16.
Neurobiol Aging ; 27(11): 1604-12, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16226349

RESUMO

This study examined the functionality of the medial temporal lobe (MTL) and posterior cingulate (PC) in mild cognitive impairment amnestic type (MCI), a syndrome that puts patients at greater risk for developing Alzheimer disease (AD). Functional MRI (fMRI) was used to identify regions normally active during encoding of novel items and recognition of previously learned items in a reference group of 77 healthy young and middle-aged adults. The pattern of activation in this group guided further comparisons between 14 MCI subjects and 14 age-matched controls. The MCI patients exhibited less activity in the PC during recognition of previously learned items, and in the right hippocampus during encoding of novel items, despite comparable task performance to the controls. Reduced fMRI signal change in the MTL supports prior studies implicating the hippocampus for encoding new information. Reduced signal change in the PC converges with recent research on its role in recognition in normal adults as well as metabolic decline in people with genetic or cognitive risk for AD. Our results suggest that a change in function in the PC may account, in part, for memory recollection failure in AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Idoso , Doença de Alzheimer/psicologia , Atrofia , Estudos de Casos e Controles , Transtornos Cognitivos/patologia , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Análise por Pareamento , Memória , Lobo Temporal/patologia , Lobo Temporal/fisiopatologia
18.
Cell Mol Life Sci ; 62(3): 299-312, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15723166

RESUMO

Recent findings from the Women's Health Initiative (WHI) have raised considerable concern over prolonged use of opposed and unopposed oral conjugated equine estrogen (CEE), given the increased risk of serious adverse effects, including stroke and venous thromboembolic complications. Furthermore, results from the WHI Memory Study (WHIMS) indicated that over 5 years of therapy with Prempro impaired performance on global cognitive tests and nearly doubled the risk of dementia. These surprising findings were contradictory to cumulative evidence from basic science, epidemiological and some intervention studies suggesting hormone therapy was cardioprotective and could potentially reduce the risk of dementia. This review paper focuses on the neurobiology of estrogen, summarizing the clinical evidence for neuroprotective and cognition-enhancing efficacy of estrogen. Further, the paper briefly discusses variables that may account for the unexpected findings of WHIMS, and offers suggestions for future research.


Assuntos
Hormônios Esteroides Gonadais/farmacologia , Fármacos Neuroprotetores/farmacologia , Ensaios Clínicos como Assunto/estatística & dados numéricos , Estrogênios/farmacologia , Feminino , Hormônios Esteroides Gonadais/fisiologia , Humanos
19.
Talanta ; 65(2): 349-57, 2005 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-18969806

RESUMO

The screen-printed four-electrode system was used as the amperometric transducer for determination of phenols and pesticides using immobilised tyrosinase, peroxidase, acetylcholinesterase and butyrylcholinesterase. Acetylthiocholine chloride was chosen as substrate for cholinesterases to measure inhibition by pesticides, hydrogen peroxide served as co-substrate for peroxidase to measure phenols. The compatibility of hydrolases and oxidoreductases working in the same array was studied. The detection of p-cresol, catechol and phenol as well as of pesticides including carbaryl, heptenophos and fenitrothion was carried out in flow-through and steady state arrangements. In addition, the effects of heavy metals (Cu(2+), Cd(2+), Fe(3+)), fluoride (NaF), benzene and dimethylsulphoxide on cholinesterase activities were evaluated. It was demonstrated that electrodes modified with hydrolases and oxidoreductases can function in the same array. The achieved R.S.D. values obtained for the flow system were below 4% for the same sensor and less than 10% within a group of five sensors. For the steady state system, R.S.D.s were approximately twice higher. One assay was completed in less than 6min. The limit of detection for catechol using tyrosinase was equal to 0.35 and 1.7muM in the flow and steady state systems, respectively. On the contrary, lower limits of detection for pesticides were achieved in the steady state system-carbaryl 26nM, heptenophos 14nM and fenitrothion 0.58muM.

20.
J Mol Endocrinol ; 31(3): 509-18, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14664711

RESUMO

Pancreatic beta-cells have low activities of the antioxidant enzyme catalase. Nitric oxide interacts with the haem group of catalase inhibiting its activity. We have studied the activity of catalase in beta-cells under conditions mimicking prediabetes and in which nitric oxide is generated from cytokine treatment in vitro. We also studied whether there is regulation of catalase enzyme activity by nitric oxide at the protein or gene expression level. RINm5F insulin-producing cells, treated for 24 h with cytokines, showed increased medium nitrite production (17+/-2.2 vs 0.3+/-0.2 pmol/ micro g protein) and significantly decreased cellular catalase activity (42.4+/-4.5%) compared with control cells. A similar reduction was seen in catalase-overexpressing RIN-CAT cells and in rat or human pancreatic islets of Langerhans. Catalase activity was also suppressed by the long-acting nitric oxide donor diethylenetriamine/nitric oxide adduct (Deta-NO) and this inhibition was reversible. The inhibition of catalase activity by cytokines in RINm5F cells was significantly reversed by the addition of the nitric oxide synthase 2 (NOS2) inhibitors nitro monomethylarginine or N-(3-(aminomethyl)benzyl)acetamidine (1400W). Protein expression was found to be unchanged in cytokine- or Deta-NO-treated RINm5F cells, while mRNA expression was marginally increased. We have shown that inhibition of catalase activity by cytokines is nitric oxide dependent and propose that this inhibition may confer increased susceptibility to cytokine- or nitric oxide-induced cell killing.


Assuntos
Catalase/metabolismo , Citocinas/farmacologia , Insulinoma/enzimologia , Óxido Nítrico/farmacologia , Neoplasias Pancreáticas/enzimologia , Amidinas/farmacologia , Animais , Benzilaminas/farmacologia , Morte Celular/fisiologia , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas/enzimologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , RNA Mensageiro/genética , Ratos , Triazenos/farmacologia , Células Tumorais Cultivadas
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