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1.
Nature ; 614(7949): 659-663, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623548

RESUMO

Transmission spectroscopy1-3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations' relatively narrow wavelength range and spectral resolving power, which precluded the unambiguous identification of other chemical species-in particular the primary carbon-bearing molecules6,7. Here we report a broad-wavelength 0.5-5.5 µm atmospheric transmission spectrum of WASP-39b8, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, measured with the JWST NIRSpec's PRISM mode9 as part of the JWST Transiting Exoplanet Community Early Release Science Team Program10-12. We robustly detect several chemical species at high significance, including Na (19σ), H2O (33σ), CO2 (28σ) and CO (7σ). The non-detection of CH4, combined with a strong CO2 feature, favours atmospheric models with a super-solar atmospheric metallicity. An unanticipated absorption feature at 4 µm is best explained by SO2 (2.7σ), which could be a tracer of atmospheric photochemistry. These observations demonstrate JWST's sensitivity to a rich diversity of exoplanet compositions and chemical processes.

2.
Opt Lett ; 38(12): 2147-9, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23939005

RESUMO

Four-wave mixing can be used to generate coherent output beams, with frequencies difficult to acquire in commercial lasers. Here, a single narrow external cavity diode laser locked to the two photon 5s-5d transition in rubidium is combined with a tapered amplifier system to produce a high power cw beam at 778 nm and used to generate coherent light at 420 nm through parametric four-wave mixing. This process is analyzed in terms of the intensity and frequency of the incoming beam as well as the atomic density of the sample. The efficiency of the process is currently limited when on resonance due to the absorption of the 420 nm beam, and modifications should allow a significant increase in output power.

3.
Anim Genet ; 44(4): 383-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23350719

RESUMO

The White Park Cattle (WPC) is an indigenous ancient breed from the British Isles which has a long-standing history in heroic sagas and documents. The WPC has retained many primitive traits, especially in their grazing behaviour and preferences. Altogether, the aura of this breed has led to much speculation surrounding its origin. In this study, we sequenced the mitogenomes from 27 WPC and three intronic fragments of genes from the Y chromosome of three bulls. We observed six novel mitogenomic lineages that have not been found in any other cattle breed so far. We found no evidence that the WPC is a descendant of a particular North or West European branch of aurochs. The WPC mitogenomes are grouped in the T3 cluster together with most other domestic breeds. Nevertheless, both molecular markers support the primitive position of the WPC within the taurine breeds.


Assuntos
Bovinos/genética , Variação Genética , Genoma Mitocondrial/genética , Cromossomo Y/genética , Animais , Sequência de Bases , Cruzamento , DNA Mitocondrial/genética , Marcadores Genéticos , Genótipo , Haplótipos , Íntrons/genética , Masculino , Dados de Sequência Molecular , Fenótipo , Filogenia , Análise de Sequência de DNA/veterinária , Reino Unido
4.
Oral Maxillofac Surg ; 26(3): 463-467, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34618280

RESUMO

INTRODUCTION: The SARS-CoV-2 pandemic forced many governments to impose nation-wide lockdowns. Government legislation forced limited travel on the population with restrictions on the normal way of life to limit spread of the SARS-CoV-2 virus. The aim of this study is to explore the effects of lockdown on the presentation of maxillofacial trauma in a level I trauma centre. METHODS: Comparative analysis was carried out using prospective and retrospective review of all consecutive patients admitted with any maxillofacial fracture in the lockdown period between 15th March and 15th June 2020 with the same period in 2019 to a Regional Trauma Maxillofacial Surgery Unit. Data included basic demographics and mechanism of injury including alcohol/drug influence, polytrauma, site of injury and treatment modality including escalation of care. RESULTS: Across both periods, there were a total of one hundred and five (n = 105) recorded episodes of traumatic fractures with fifty-three (n = 53) in the pre-lockdown cohort and fifty-two (n = 52) in the lockdown. Included patients were significantly (p = 0.024) older during lockdown (mean age 41.44 years SD 20.70, range 5-96) with no differences in gender distribution between cohorts (p = 0.270). Patients in lockdown were more likely to be involved in polytrauma (p < 0.05) and have sustained their injury by cycling/running or any outdoor related activity (p = 0.013). Lockdown saw a significant reduction in alcohol and drug related violence (p < 0.05). Significantly more patients required operative management (p = 0.038). CONCLUSION: Local lockdowns form part of the governments public health strategy for managing future outbreaks of SARS-CoV-2. Our study showed no significant reduction in volume of trauma during lockdown. It is vital that hospitals maintain trauma capacity to ensure that patients are treated in a timely manner.


Assuntos
COVID-19 , Fraturas Ósseas , Traumatismos Maxilofaciais , Traumatismo Múltiplo , Adulto , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Humanos , Traumatismos Maxilofaciais/epidemiologia , Traumatismos Maxilofaciais/cirurgia , Traumatismo Múltiplo/epidemiologia , Traumatismo Múltiplo/cirurgia , Pandemias , Estudos Prospectivos , Estudos Retrospectivos , SARS-CoV-2 , Centros de Traumatologia
5.
Heredity (Edinb) ; 106(2): 261-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20551978

RESUMO

Recently developed Bayesian genotypic clustering methods for analysing genetic data offer a powerful tool to evaluate the genetic structure of domestic farm animal breeds. The unit of study with these approaches is the individual instead of the population. We aimed to empirically evaluate various individual-based population genetic statistical methods for characterization of genetic diversity and structure of livestock breeds. Eighteen British pig populations, comprising 819 individuals, were genotyped at 46 microsatellite markers. Three Bayesian genotypic clustering approaches, principle component analysis (PCA) and phylogenetic reconstruction were applied to individual multilocus genotypes to infer the genetic structure and diversity of the British pig breeds. Comparisons of the three Bayesian genotypic clustering methods (STRUCTURE, BAPS and STRUCTURAMA) revealed some broad similarities but also some notable differences. Overall, the methods agreed that majority of the British pig breeds are independent genetic units with little evidence of admixture. The three Bayesian genotypic clustering methods provided complementary, biologically credible clustering solutions but at different levels of resolution. BAPS detected finer genetic differentiation and in some cases, populations within breeds. Consequently, it estimated a greater number of underlying genetic populations (K, in the notation of Bayesian clustering methods). Two of the Bayesian methods (STRUCTURE and BAPS) and phylogenetic reconstruction provided similar success in assignment of individuals, supporting the use of these methods for breed assignment.


Assuntos
Modelos Estatísticos , Suínos/genética , Animais , Teorema de Bayes , Frequência do Gene , Variação Genética , Genética Populacional , Genótipo , Filogenia , Análise de Componente Principal , Reino Unido
6.
J Inherit Metab Dis ; 32 Suppl 1: S127-35, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19319660

RESUMO

Patients with MPS II often present with limitations to functional mobility. With the advent of enzyme replacement therapy (ERT), robust assessment tools are important to assess response to treatment. The aim of this study was to see if the GAITRite™ system (electronic pressure sensitive walkway) could identify any changes to gait pattern following commencement of ERT. Six boys with MPS type II were assessed at baseline and at intervals post commencing ERT. Four individual characteristics of gait were studied - velocity, cadence, step length and base of support. Changes in parameters for each individual could be analysed and be compared with age matched controls. The data generated from the GAITRite™ indicated all six boys had changes to their gait pattern. The most notable changes were in velocity, step length and base of support. The GAITRite™ was found to identify changes in gait parameters in this group of patients. It is an accessible way of providing both quantitative and qualitative analysis of gait in the clinical environment, and could potentially be used to monitor response to treatment. Larger studies are needed to corroborate our findings, as well as to establish the GAITRite™ as a monitoring tool.


Assuntos
Terapia de Reposição de Enzimas , Marcha , Iduronato Sulfatase/uso terapêutico , Mucopolissacaridose II/tratamento farmacológico , Mucopolissacaridose II/fisiopatologia , Fenômenos Biomecânicos , Estudos de Casos e Controles , Criança , Pré-Escolar , Humanos , Masculino , Mucopolissacaridose II/complicações , Doenças Musculoesqueléticas/tratamento farmacológico , Doenças Musculoesqueléticas/etiologia , Doenças Musculoesqueléticas/fisiopatologia , Proteínas Recombinantes/uso terapêutico , Caminhada
7.
Cancer Res ; 55(5): 999-1001, 1995 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-7867012

RESUMO

Human astrocytomas frequently overexpress wild-type p53, which suggests that gliomas have evolved a mechanism to subvert p53-mediated apoptosis. bcl-2 inhibits apoptosis mediated by p53, and it is expressed in several human cancers. We therefore examined a series of human gliomas to determine whether bcl-2 is expressed and whether this expression is associated with tumors which have wild-type p53. Twenty-eight paraffin-embedded gliomas (3 WHO grade II, 13 grade III, 12 grade IV) were immunohistochemically stained for bcl-2 and p53. p53 mutations were identified with single strand conformation polymorphism and DNA sequencing. Sixteen of 28 (57%) tumors expressed bcl-2, and bcl-2 expression was associated with wild-type p53 (P < 0.01). Among gliomas which overexpressed p53, bcl-2 was positive in 7 of 7 tumors with wild-type p53 but in only 1 of 7 with mutant p53 (P < 0.01). We conclude that bcl-2 is frequently expressed in human gliomas and that expression is more common in tumors with wild-type p53.


Assuntos
Astrocitoma/química , Glioma/química , Proteínas Proto-Oncogênicas/análise , Proteína Supressora de Tumor p53/análise , Apoptose/fisiologia , Astrocitoma/genética , Astrocitoma/patologia , Expressão Gênica , Genes p53/genética , Glioma/genética , Glioma/patologia , Imuno-Histoquímica , Mutação , Inclusão em Parafina , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2 , Proteína Supressora de Tumor p53/genética
8.
Neurology ; 47(4): 1088-90, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8857752

RESUMO

The inferolateral trunk arises from the internal carotid artery at C-4 and provides vascular supply to cranial nerves III to VI. We report a patient who developed neuropathies of cranial nerves III, V1-3, and VI, 48 hours after infusion of cisplatin into the right internal carotid artery for an anaplastic oligoastrocytoma. The clinical and radiographic findings implicated direct toxicity to nerves in the distribution of the inferolateral trunk. We found additional cases by review of published brain tumor chemotherapy trials, thus identifying a novel, toxic neurovascular mechanism for injury to cranial nerves III to VI.


Assuntos
Cisplatino/efeitos adversos , Doenças dos Nervos Cranianos/etiologia , Adulto , Astrocitoma/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Artérias Carótidas , Cisplatino/administração & dosagem , Humanos , Imageamento por Ressonância Magnética , Masculino
9.
Science ; 223(4639): 878, 1984 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17781607
10.
Brain Res ; 218(1-2): 189-206, 1981 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-7272735

RESUMO

Thirty days after castration the concentration of dopamine (DA) was significantly reduced in the septum and n. accumbens septi, but not in the caudate-putamen, of male rat brain. The concentrations of dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), the principle metabolites of DA, also tended to be lower in septum and n. accumbens septi after castration. Chronic s.c. administration of testosterone (T), estradiol (E2), 5 alpha-dihydrotestosterone (DHT), or E2 plus DHT in silastic capsules effectively reversed these effects of castration in septum and n. accumbens septi without affecting concentrations of DA, DOPAC, or HVA in caudate-putamen. The accumulation of DOPA after inhibition of aromatic amino acid decarboxylase activity, which was taken as an in vivo index of tyrosine hydroxylase activity, was not affected in these brain regions by long-term castration or by chronic administration of DHT to castrated males. Acute administration of haloperidol caused equivalent, significant increments in concentrations of DOPAC and HVA in all brain regions studied, regardless of whether castrated rats had been implanted with DHT capsules or no hormone. However, in the absence of haloperidol treatment the concentration of DOPAC in septum and n. accumbens septi, but not in caudate-putamen, was significantly higher in castrated rats implanted with DHT as opposed to no hormone. These results suggest that chronic exposure to T, or to its neural metabolites, E2 and DHT, selectively enhances metabolic activity in mesolimbic DA neurons.


Assuntos
Corpo Estriado/metabolismo , Di-Hidrotestosterona/farmacologia , Dopamina/metabolismo , Estradiol/farmacologia , Núcleo Accumbens/metabolismo , Núcleos Septais/metabolismo , Substância Negra/metabolismo , Testosterona/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Castração , Corpo Estriado/efeitos dos fármacos , Ácido Homovanílico/metabolismo , Masculino , Núcleo Accumbens/efeitos dos fármacos , Ratos , Substância Negra/efeitos dos fármacos
11.
Perit Dial Int ; 21 Suppl 3: S144-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11887809

RESUMO

OBJECTIVE: Patients on continuous ambulatory peritoneal dialysis (CAPD) must receive an increased dialysis dose as they lose residual renal function so that total clearances are optimized. The dialysis dose may be increased by increasing the exchange volume. Patients on CAPD are often reluctant to use a greater exchange volume, fearing increased pain and discomfort and an altered body image. To assess patient perception of various fill volumes, we studied 12 stable patients currently treated with 2-L exchanges who had no surgical contraindication to larger fill volumes. METHOD: After an overnight dwell, patients received a 2-L, 2.5-L, or 3-L exchange of Baxter PD4 (Baxter Healthcare SA, Castlebar, Ireland) for 3 hours in a randomized crossover design. Patients and staff were both blinded to the fill volume. At the beginning and end of the exchange, intraperitoneal hydrostatic pressure (IPP) in the supine position was measured, and the patient's perception of the exchange was evaluated using the validated McGill Pain Questionnaire (MPG). RESULTS: Initial IPP increased with increasing fill volume (12.5 +/- 3.7 cmH2O vs 16.1 +/- 4.2 cmH2O vs 18.7 +/- 3.6 cmH2O for 2, 2.5 L, and 3L, respectively). For all fill volumes, IPP had fallen by the end of the 3-hour dwell, at which time it was similar to that after an overnight 2-L exchange. The pain rating index by was generally low for all exchange volumes and did not correlate with IPP. Minor degrees of discomfort were reported by 4, 2, and 1 patients with 3-L, 2.5-L, and 2-L exchanges respectively. CONCLUSION: Our study suggests that, despite an increased IPP, larger exchange volumes are generally well tolerated by patients, with only a minority of patients feeling mild discomfort.


Assuntos
Soluções para Diálise/administração & dosagem , Diálise Peritoneal Ambulatorial Contínua , Adulto , Idoso , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Pressão Hidrostática , Masculino , Pessoa de Meia-Idade , Medição da Dor , Cavidade Peritoneal/fisiopatologia , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos
15.
Haemophilia ; 13(5): 542-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17880441

RESUMO

Development of haemophilic arthropathy has long-term implications for functional mobility in people with haemophilia, but early manifestations are often asymptomatic and difficult to identify. Earlier identification of joint damage may improve outcomes. The aim of this case note review was to determine whether the GAITRite system (electronic pressure sensitive walkway) could identify early changes in gait patterns in boys with haemophilia compared with their peers. Clinic data from medical and physiotherapy notes of boys with severe haemophilia were compared with data from age and leg length-matched controls. Data from two consecutive walks at preferred speed were collected on all participants using the GAITRite system. Clinic assessment notes from 26 boys (aged 7-17 years) with severe haemophilia were identified. Of these, 20 boys had no evidence of joint pathology on assessment and six boys had radiographic evidence of arthropathy. When these data were compared with normal controls, there were statistically significant increases in swing time, stance time, single support and double support in the asymptomatic group (P < 0.01) suggesting subtle early compensatory changes in gait pattern. The children with arthropathy had additional significant differences in their gait compared with matched controls. These differences included normalized velocity, step length, stride length, step time and base of support (P < 0.01). The GAITRite system appears sensitive enough to identify early subtle changes in gait and differentiate between asymptomatic boys with haemophilia and those with arthropathy in comparison with a matched control group. The electronic walkway is an accessible and portable means of providing quantitative gait analysis in the clinical environment. This is an important finding as early identification of gait changes may provide clinicians with the opportunity to intervene with the aim of arresting progression of joint damage.


Assuntos
Diagnóstico por Computador/instrumentação , Marcha/fisiologia , Hemofilia A/fisiopatologia , Artropatias/etiologia , Adolescente , Análise de Variância , Criança , Diagnóstico por Computador/métodos , Hemofilia A/diagnóstico , Humanos , Artropatias/fisiopatologia , Masculino , Avaliação de Resultados em Cuidados de Saúde , Reprodutibilidade dos Testes , Projetos de Pesquisa , Sensibilidade e Especificidade
16.
J Hered ; 97(3): 244-52, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16740626

RESUMO

DNA markers are commonly used for large-scale evaluation of genetic diversity in farm animals, as a component of the management of animal genetic resources. AFLP markers are useful for such studies as they can be generated relatively simply; however, challenges in analysis arise from their dominant scoring and the low level of polymorphism of some markers. This paper describes the results obtained with a set of AFLP markers in a study of 59 pig breeds. AFLP fingerprints were generated using four primer combinations (PC), yielding a total of 148 marker loci, and average harmonic mean of breed sample size was 37.3. The average proportion of monomorphic populations was 63% (range across loci: 3%-98%). The moment-based method of Hill and Weir (2004, Mol Ecol 13:895-908) was applied to estimate gene frequencies, gene diversity (F(ST)), and Reynolds genetic distances. A highly significant average F(ST) of 0.11 was estimated, together with highly significant PC effects on gene diversity. The variance of F(ST) across loci also significantly exceeded the variance expected under the hypothesis of AFLP neutrality, strongly suggesting the sensitivity of AFLP to selection or other forces. Moment estimates were compared to estimates derived from the square root estimation of gene frequency, as currently applied for dominant markers, and the biases incurred in the latter method were evaluated. The paper discusses the hypotheses underlying the moment estimations and various issues relating to the biallelic, dominant, and lowly polymorphic nature of this set of AFLP markers and to their use as compared to microsatellites for measuring genetic diversity.


Assuntos
Marcadores Genéticos , Variação Genética , Polimorfismo Genético , Suínos/genética , Animais , Repetições de Microssatélites/genética
17.
Anim Genet ; 37(3): 189-98, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16734675

RESUMO

An important prerequisite for a conservation programme is a comprehensive description of genetic diversity. The aim of this study was to use anonymous genetic markers to assess the between- and the within-population components of genetic diversity for European pig breeds at the scale of the whole continent using microsatellites. Fifty-eight European pig breeds and lines were analysed including local breeds, national varieties of international breeds and commercial lines. A sample of the Chinese Meishan breed was also included. Eleven additional breeds from a previous project were added for some analyses. Approximately 50 individuals per breed were genotyped for a maximum of 50 microsatellite loci. Substantial within-breed variability was observed, with the average expected heterozygosity and observed number of alleles per locus being 0.56 [range 0.43-0.68] and 4.5 respectively. Genotypic frequencies departed from Hardy-Weinberg expectations (P < 0.01) in 15 European populations, with an excess of homozygotes in 12 of them. The European breeds were on average genetically very distinct, with a Wright F(ST) index value of 0.21. The Neighbour-Joining tree drawn from the Reynolds distances among the breeds showed that the national varieties of major breeds and the commercial lines were mostly clustered around their breeds of reference (Duroc, Hampshire, Landrace, Large White and Piétrain). In contrast, local breeds, with the exception of the Iberian breeds, exhibited a star-like topology. The results are discussed in the light of various forces, which may have driven the recent evolution of European pig breeds. This study has consequences for the interpretation of biodiversity results and will be of importance for future conservation programmes.


Assuntos
Variação Genética , Repetições de Microssatélites , Suínos/genética , Alelos , Animais , Biodiversidade , Cruzamento , Europa (Continente) , Frequência do Gene , Genótipo , Suínos/classificação
18.
Anim Genet ; 37(3): 232-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16734682

RESUMO

The use of DNA markers to evaluate genetic diversity is an important component of the management of animal genetic resources. The Food and Agriculture Organisation of the United Nations (FAO) has published a list of recommended microsatellite markers for such studies; however, other markers are potential alternatives. This paper describes results obtained with a set of amplified fragment length polymorphism (AFLP) markers as part of a genetic diversity study of European pig breeds that also utilized microsatellite markers. Data from 148 AFLP markers genotyped across samples from 58 European and one Chinese breed were analysed. The results were compared with previous analyses of data from 50 microsatellite markers genotyped on the same animals. The AFLP markers had an average within-breed heterozygosity of 0.124 but there was wide variation, with individual markers being monomorphic in 3-98% of the populations. The biallelic and dominant nature of AFLP markers creates a challenge for their use in genetic diversity studies as each individual marker contains limited information and AFLPs only provide indirect estimates of the allelic frequencies that are needed to estimate genetic distances. Nonetheless, AFLP marker-based characterization of genetic distances was consistent with expectations based on breed and regional distributions and produced a similar pattern to that obtained with microsatellites. Thus, data from AFLP markers can be combined with microsatellite data for measuring genetic diversity.


Assuntos
Polimorfismo Genético , Suínos/genética , Alelos , Animais , Cruzamento , Europa (Continente) , Marcadores Genéticos , Genótipo , Heterozigoto , Repetições de Microssatélites , Filogenia , Suínos/classificação
19.
Arteriosclerosis ; 6(5): 465-74, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3767691

RESUMO

The atherogenicity of dietary peanut oil (PO) was examined in cynomolgus monkeys fed semipurified diets for 15 months. Four groups of six monkeys were fed diets containing 0.22 mg/kcal (0.1%) cholesterol and 0%, 5%, 10%, or 20% PO. An additional group was fed 2.0% cholesterol and 20% PO to serve as a literature control. Increasing the concentration of PO in the diet was associated with significant decreases in total plasma cholesterol (p less than 0.05) and the total/HDL cholesterol ratio (p less than 0.05) and an increase in the terminal HDL cholesterol concentration (p less than 0.05). Intimal thickness and composition were determined from cross sections of the thoracic aorta and the iliac and coronary arteries. Increasing dietary PO was associated with decreases in thickness (p less than 0.005), lipid (p less than 0.001), and smooth muscle cells (p less than 0.005) in the aortic intima. Aortic intimal lipid was positively correlated with the ratio of total to HDL cholesterol (r2 = 0.78, p less than 0.05). Monkeys fed 2.0% cholesterol and 20% PO revealed extensive atherosclerosis in all three arterial sites compared with those of any other group. Whereas the dietary fat effect was most demonstrable in the aorta, dietary cholesterol had a greater effect on the iliac and coronary arteries than it did on the aorta. Under these circumstances, dietary PO was not atherogenic in cynomolgus monkeys when fed with a concentration of cholesterol equivalent to that consumed by humans.


Assuntos
Arteriosclerose/etiologia , Dieta Aterogênica , Gorduras Insaturadas na Dieta/efeitos adversos , Óleos de Plantas/uso terapêutico , Animais , Aorta Torácica/patologia , Arteriosclerose/sangue , Arteriosclerose/patologia , Colesterol na Dieta/efeitos adversos , HDL-Colesterol/sangue , Vasos Coronários/patologia , Gorduras Insaturadas na Dieta/sangue , Feminino , Artéria Ilíaca/patologia , Macaca fascicularis , Óleo de Amendoim
20.
J Neurol Neurosurg Psychiatry ; 60(1): 102-5, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8558135

RESUMO

Some patients ultimately diagnosed with primary CNS lymphoma (PCNSL) have transient symptomatic contrast enhancing lesions. These "sentinel lesions" of PCNSL recede spontaneously or with corticosteroid treatment and present an important diagnostic dilemma because they show variable, but non-diagnostic histopathological features. Four previously healthy, immunocompetent patients aged 49 to 58 years had contrast enhancing intraparenchymal brain lesions. Before biopsy, three of the four were treated with corticosteroids. Initial biopsies showed demyelination with axonal sparing in two, non-specific inflammation in one, and normal brain in one. Infiltrating lymphocytes predominantly expressed T cell markers with rare B cells. All four patients recovered within two to four weeks after the initial biopsy and imaging studies showed resolution of the lesions. The CSF was normal in three of the four patients tested; oligoclonal bands were absent in both of the two tested. After seven to 11 months, each patient developed new symptomatic lesions in a different region of the brain, biopsy of which showed a B cell PCNSL. The mechanism of spontaneous involution of sentinel lesions is not understood, but may represent host immunity against the tumour. Sentinel lesions of PCNSL should be considered in patients with contrast enhancing focal parenchymal lesions that show non-specific or demyelinative histopathological changes. Close clinical and radiographic follow up is essential if PCNSL is to be diagnosed early in such patients.


Assuntos
Neoplasias Encefálicas/patologia , Linfoma de Células B/patologia , Corticosteroides/uso terapêutico , Biópsia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/imunologia , Doenças Desmielinizantes/etiologia , Diagnóstico Diferencial , Feminino , Humanos , Inflamação , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/imunologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Fatores de Tempo
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