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1.
J Dairy Sci ; 106(5): 3411-3420, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36894418

RESUMO

The most frequently reported definition of cystic ovarian disease in cattle is an abnormally persistent follicle (>7 to 10 d) with a diameter >25 mm. Discrimination between luteal and follicular ovarian cystic structures has traditionally been conducted by measuring the rim width of luteal tissue. The most common practice used in the field for diagnosis of cystic ovarian disease is examination by rectal palpation with or without the use of a B-mode ultrasound. Color Doppler ultrasound technology allows assessment of blood flow area measurements in the ovary, which has been proposed as a potential indirect measure for plasma progesterone (P4) concentrations. The objective of this study was to compare the diagnostic accuracy of differentiating luteal structures from follicular ovarian cysts using measures collected with B-mode and color Doppler transrectal ultrasonography. The definition of an ovarian cyst was a follicle greater than 20 mm in diameter in the absence of a corpus luteum that persisted for at least 10 d. A 3-mm luteal rim width was used to differentiate follicular and luteal cysts. A total of 36 cows were enrolled in the study during routine herd reproductive examination visits, with 26 and 10 having follicular and luteal cysts, respectively. Cows enrolled in the study were examined using a Mini-ExaPad mini ultrasound with color Doppler capabilities (IMV Imaging Ltd.). Blood samples were collected from each cow to measure P4 serum concentrations. History and signalment of each cow, including days in milk, lactation, times bred, days since last heat, milk composition, and somatic cell counts, were retrieved from an online database (DairyComp 305, Valley Agricultural Software). The accuracy of diagnosing follicular from luteal cysts based on luteal rim thickness was analyzed by receiver operating characteristic (ROC) curve using P4 as the gold standard, where P4 concentrations exceeding 1 ng/mL was defined as luteal, and all other structures with less P4 were considered follicular. Luteal rim and blood flow area were selected for further analysis because they presented the best ROC curves for differentiating cystic ovarian structures, with areas under the curve of 0.80 and 0.76, respectively. Luteal rim width of 3 mm was used as the cutoff standard in the study, resulting in sensitivity and specificity of 50% and 86%, respectively. Blood flow area of 0.19 cm2 was used as the cutoff standard in the study, resulting in sensitivity and specificity of 79% and 86%, respectively. When combining the use of luteal rim width and blood flow area to differentiate cystic ovarian structures, a parallel approach resulted in sensitivity and specificity of 73% and 93%, respectively, whereas an in-series approach resulted in sensitivity and specificity of 35% and 100%, respectively. In conclusion, the use of color Doppler ultrasonography when discriminating between luteal and follicular ovarian cysts in dairy cattle resulted in higher diagnostic accuracy compared with using B-mode ultrasonography alone.


Assuntos
Doenças dos Bovinos , Cistos Ovarianos , Feminino , Bovinos , Animais , Progesterona , Corpo Lúteo/diagnóstico por imagem , Cistos Ovarianos/diagnóstico por imagem , Cistos Ovarianos/veterinária , Folículo Ovariano , Ultrassonografia Doppler em Cores/veterinária , Doenças dos Bovinos/diagnóstico por imagem
2.
Neuropathol Appl Neurobiol ; 47(1): 26-42, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32464705

RESUMO

AIMS: Neuroferritinopathy (NF) or hereditary ferritinopathy (HF) is an autosomal dominant movement disorder due to mutation in the light chain of the iron storage protein ferritin (FTL). HF is the only late-onset neurodegeneration with brain iron accumulation disorder and study of HF offers a unique opportunity to understand the role of iron in more common neurodegenerative syndromes. METHODS: We carried out pathological and biochemical studies of six individuals with the same pathogenic FTL mutation. RESULTS: CNS pathological changes were most prominent in the basal ganglia and cerebellar dentate, echoing the normal pattern of brain iron accumulation. Accumulation of ferritin and iron was conspicuous in cells with a phenotype suggesting oligodendrocytes, with accompanying neuronal pathology and neuronal loss. Neurons still survived, however, despite extensive adjacent glial iron deposition, suggesting neuronal loss is a downstream event. Typical age-related neurodegenerative pathology was not normally present. Uniquely, the extensive aggregates of ubiquitinated ferritin identified indicate that abnormal FTL can aggregate, reflecting the intrinsic ability of FTL to self-assemble. Ferritin aggregates were seen in neuronal and glial nuclei showing parallels with Huntington's disease. There was neither evidence of oxidative stress activation nor any significant mitochondrial pathology in the affected basal ganglia. CONCLUSIONS: HF shows hallmarks of a protein aggregation disorder, in addition to iron accumulation. Degeneration in HF is not accompanied by age-related neurodegenerative pathology and the lack of evidence of oxidative stress and mitochondrial damage suggests that these are not key mediators of neurodegeneration in HF, casting light on other neurodegenerative diseases characterized by iron deposition.


Assuntos
Apoferritinas/metabolismo , Encéfalo/efeitos dos fármacos , Distúrbios do Metabolismo do Ferro/metabolismo , Ferro/metabolismo , Distrofias Neuroaxonais/metabolismo , Animais , Apoferritinas/química , Apoferritinas/genética , Encéfalo/patologia , Modelos Animais de Doenças , Ferritinas/química , Ferritinas/genética , Ferritinas/metabolismo , Humanos , Distúrbios do Metabolismo do Ferro/patologia , Pessoa de Meia-Idade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mutação/genética , Distrofias Neuroaxonais/patologia , Doenças Neurodegenerativas/patologia , Estresse Oxidativo/efeitos dos fármacos , Agregados Proteicos/fisiologia
3.
Neuropathol Appl Neurobiol ; 45(6): 597-608, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30422353

RESUMO

AIMS: Lewy body diseases are neuropathologically characterized by the abnormal accumulation of α-synuclein (α-syn) protein within vulnerable neurons. Although studies have evaluated α-syn in post mortem brain tissue, previous findings have been limited by typically employing pan-α-syn antibodies that may not recognize disease-relevant forms of protein. We investigated the presence of α-syn species present in post mortem brain tissues from Lewy body disease and Alzheimer's disease. METHODS: Soluble and insoluble/aggregated α-syn from frontal cortex of post mortem brain tissues form Parkinson's disease (PD), dementia with Lewy bodies (DLB), Alzheimer's disease (AD) and aged control cases were sequentially extracted using buffers with increasing detergent concentrations. Enzyme-linked immunosorbent assay (ELISA) was used to quantify the levels of total-, oligomeric- and phosphorylated-Ser129-α-syn (t-, o- and pS129-α-syn). ELISA data were validated by western blot and compared to histological data from the same region of the contralateral hemisphere. RESULTS: There was no difference in t-α-syn levels between groups in the aqueous-soluble, detergent-soluble or urea-soluble tissue fractions. However, aqueous-soluble non-phosphorylated o-α-syn was increased not only in PD and DLB but also in AD without neocortical Lewy bodies. In PD and AD, pS129-α-syn was increased in the detergent-soluble tissue fragment and, in AD, this was positively correlated with the burden of tau pathology. Increased levels of urea-soluble pS129-α-syn were demonstrated only in DLB tissue lysates but this did not correlate with Lewy body pathological burden. CONCLUSIONS: Taken together, these findings suggest that DLB have elevated levels of insoluble pS129-α-syn, but that increased levels of aqueous-soluble o-α-syn and detergent-soluble pS129-α-syn are also observed in PD and AD, suggesting different changes to α-syn across the spectrum of neurodegenerative proteopathies.


Assuntos
Doença de Alzheimer/metabolismo , Córtex Cerebral/metabolismo , Doença por Corpos de Lewy/metabolismo , alfa-Sinucleína/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Córtex Cerebral/patologia , Feminino , Humanos , Doença por Corpos de Lewy/patologia , Masculino , Fosforilação , Proteínas tau/metabolismo
4.
Phys Rev Lett ; 115(21): 217602, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26636873

RESUMO

We have utilized time-domain magnetoterahertz spectroscopy to investigate the low-frequency optical response of the topological insulator Cu_{0.02}Bi_{2}Se_{3} and Bi_{2}Se_{3} films. With both field and frequency dependence, such experiments give sufficient information to measure the mobility and carrier density of multiple conduction channels simultaneously. We observe sharp cyclotron resonances (CRs) in both materials. The small amount of Cu incorporated into the Cu_{0.02}Bi_{2}Se_{3} induces a true bulk insulator with only a single type of conduction with a total sheet carrier density of ~4.9×10^{12}/cm^{2} and mobility as high as 4000 cm^{2}/V·s. This is consistent with conduction from two virtually identical topological surface states (TSSs) on the top and bottom of the film with a chemical potential ~145 meV above the Dirac point and in the bulk gap. The CR broadens at high fields, an effect that we attribute to an electron-phonon interaction. This assignment is supported by an extended Drude model analysis of the zero-field Drude conductance. In contrast, in normal Bi_{2}Se_{3} films, two conduction channels were observed, and we developed a self-consistent analysis method to distinguish the dominant TSSs and coexisting trivial bulk or two-dimensional electron gas states. Our high-resolution Faraday rotation spectroscopy on Cu_{0.02}Bi_{2}Se_{3} paves the way for the observation of quantized Faraday rotation under experimentally achievable conditions to push the chemical potential in the lowest Landau level.

5.
Phys Rev Lett ; 114(20): 207201, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-26047249

RESUMO

Theoretical models of the spin-orbital liquid (SOL) FeSc2S4 have predicted it to be in close proximity to a quantum critical point separating a spin-orbital liquid phase from a long-range ordered magnetic phase. Here, we examine the magnetic excitations of FeSc2S4 through time-domain terahertz spectroscopy under an applied magnetic field. At low temperatures an excitation emerges that we attribute to a singlet-triplet excitation from the SOL ground state. A threefold splitting of this excitation is observed as a function of applied magnetic field. As singlet-triplet excitations are typically not allowed in pure spin systems, our results demonstrate the entangled spin and orbital character of singlet ground and triplet excited states. Using experimentally obtained parameters we compare to existing theoretical models to determine FeSc2S4's proximity to the quantum critical point. In the context of these models, we estimate the characteristic length of the singlet correlations to be ξ/(a/2)≈8.2 (where a/2 is the nearest neighbor lattice constant), which establishes FeSc2S4 as a SOL with long-range entanglement.

6.
Arch Toxicol ; 89(10): 1811-25, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25693864

RESUMO

Evidence indicates that Parkinson's disease (PD), in addition to having a genetic aetiology, has an environmental component that contributes to disease onset and progression. The exact nature of any environmental agent contributing to PD is unknown in most cases. Given its similarity to paraquat, an agrochemical removed from registration in the EU for its suspected potential to cause PD, we have investigated the in vitro capacity of the related herbicide Diquat to cause PD-like cell death. Diquat showed greater toxicity towards SH-SY5Y neuroblastoma cells and human midbrain neural cells than paraquat and also MPTP, which was independent of dopamine transporter-mediated uptake. Diquat caused cell death independently of caspase activation, potentially via RIP1 kinase, with only a minor contribution from apoptosis, which was accompanied by enhanced reactive oxygen species production in the absence of major inhibition of complex I of the mitochondrial respiratory chain. No changes in α-synuclein expression were observed following 24-h or 4-week exposure. Diquat may, therefore, kill neural tissue by programmed necrosis rather than apoptosis, reflecting the pathological changes seen following high-level exposure, although its ability to promote PD is unclear.


Assuntos
Apoptose/efeitos dos fármacos , Diquat/toxicidade , Herbicidas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Intoxicação por MPTP/patologia , Mitocôndrias/metabolismo , Necrose/induzido quimicamente , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Neuroblastoma/patologia , Paraquat/toxicidade , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Fatores de Tempo
7.
Phys Rev Lett ; 112(13): 137403, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24745454

RESUMO

Kink bound states in the one-dimensional ferromagnetic Ising chain compound CoNb2O6 have been studied using high-resolution time-domain terahertz spectroscopy in zero applied magnetic field. When magnetic order develops at low temperature, nine bound states of kinks become visible. Their energies can be modeled exceedingly well by the Airy function solutions to a 1D Schrödinger equation with a linear confining potential. This sequence of bound states terminates at a threshold energy near 2 times the energy of the lowest bound state. Above this energy scale we observe a broad feature consistent with the onset of the two particle continuum. At energies just below this threshold we observe a prominent excitation that we interpret as a novel bound state of bound states--two pairs of kinks on neighboring chains.

8.
Nat Genet ; 28(4): 350-4, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11438811

RESUMO

We describe here a previously unknown, dominantly inherited, late-onset basal ganglia disease, variably presenting with extrapyramidal features similar to those of Huntington's disease (HD) or parkinsonism. We mapped the disorder, by linkage analysis, to 19q13.3, which contains the gene for ferritin light polypeptide (FTL). We found an adenine insertion at position 460-461 that is predicted to alter carboxy-terminal residues of the gene product. Brain histochemistry disclosed abnormal aggregates of ferritin and iron. Low serum ferritin levels also characterized patients. Ferritin, the main iron storage protein, is composed of 24 subunits of two types (heavy, H and light, L) which form a soluble, hollow sphere. Brain iron deposition increases normally with age, especially in the basal ganglia, and is a suspected causative factor in several neurodegenerative diseases in which it correlates with visible pathology, possibly by its involvement in toxic free-radical reactions. We found the same mutation in five apparently unrelated subjects with similar extrapyramidal symptoms. An abnormality in ferritin strongly indicates a primary function for iron in the pathogenesis of this new disease, for which we propose the name 'neuroferritinopathy'.


Assuntos
Doenças dos Gânglios da Base/genética , Ferritinas/genética , Genes Dominantes/genética , Mutação , Subunidades Proteicas , Adulto , Idade de Início , Doenças dos Gânglios da Base/diagnóstico , Doenças dos Gânglios da Base/epidemiologia , Sequência de Bases , Encéfalo/patologia , Cromossomos Humanos Par 19/genética , Análise Mutacional de DNA , Feminino , Ferritinas/metabolismo , Efeito Fundador , Ligação Genética , Globo Pálido/metabolismo , Globo Pálido/patologia , Humanos , Ferro/metabolismo , Escore Lod , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Homologia de Sequência de Aminoácidos , Terminologia como Assunto
9.
Opt Express ; 20(11): 12303-17, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22714218

RESUMO

We present high precision measurements of polarization rotations in the frequency range from 0.1 to 2.5 THz using a polarization modulation technique. A motorized stage rotates a polarizer at ~ 80 Hz, and the resulting modulation of the polarization is measured by a lock-in technique. We achieve an accuracy of 0.050° (900 µrad) and a precision of 0.02° (350 µrad) for small rotation angles. A detailed mathematical description of the technique is presented, showing its ability to fully characterize elliptical polarizations from 0.1 to 2.5 THz.


Assuntos
Refratometria/instrumentação , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Radiação Terahertz
11.
Neurosci Lett ; 711: 134437, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31422098

RESUMO

Parkinson's disease (PD) is characterised pathologically by degeneration of the dopaminergic (DA) neurones of the substantia nigra pars compacta (SNpc) and the presence of α-synuclein containing Lewy body inclusions. Trichloroethylene (TCE) has been suggested as a potential environmental chemical that may contribute to the development of PD, via conversion to the neurotoxin, 1-Trichloromethyl-1,2,3,4-tetrahydro-ß-carboline (TaClo). We investigated the effect of an 8 week exposure to TCE or TaClo on wild type and, as an experimental model of PD, A30P mutant α-synuclein overexpressing mice using a combination of behaviour and pathology. TCE or TaClo exposure caused significant DA neuronal loss within the SNpc in both wild type and transgenic mice. Cell numbers were lower in A30P animals than wild type, however, no additive effect of TCE or TaClo exposure and A30P overexpression was found. TCE or TaClo did not appear to lead to acceleration of motor or cognitive deficits in either wild type or A30P mutant mice, potentially because of the modest reductions of DA neuronal number in the SNpc. Our results do however suggest that TCE exposure could be a possible factor in development of PD like changes following exposure.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Degeneração Neural/patologia , Neurotoxinas/toxicidade , Transtornos Parkinsonianos/patologia , Tricloroetileno/toxicidade , Animais , Neurônios Dopaminérgicos/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Neurotoxinas/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Tricloroetileno/metabolismo , alfa-Sinucleína/genética
12.
Brain ; 130(Pt 2): 357-67, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17235124

RESUMO

Several hereditary small vessel diseases (SVDs) of the brain have been reported in recent years. In 1977, Sourander and Wålinder described hereditary multi-infarct dementia (MID) in a Swedish family. In the same year, Stevens and colleagues reported chronic familial vascular encephalopathy in an English family bearing a similar phenotype. These disorders have invariably been suggested to be cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) but their genetic identities remain unknown. We used molecular, radiological and neuropathological methods to characterize these disorders. Direct DNA sequencing unexpectedly confirmed that affected members of the English family carried the R141C mutation in the NOTCH3 gene diagnostic of CADASIL. However, we did not detect any pathogenic mutations in the entire 8091 bp reading frame of NOTCH3 or find clear evidence for NOTCH3 gene linkage in the Swedish DNA. This was consistent with the lack of hyperintense signals in the anterior temporal pole and external capsule in Swedish subjects upon magnetic resonance imaging. We further found no evidence for granular osmiophilic material in skin biopsy or post-mortem brain samples of affected members in the Swedish family. In addition, there was distinct lack of NOTCH3 N-terminal fragments in the cerebral microvasculature of the Swedish hereditary MID subjects compared to the intense accumulation in the English family afflicted with CADASIL. Several differences in arteriosclerotic changes in both the grey and white matter were also noted between the disorders. The sclerotic index values, density of collagen IV immunoreactivity in the microvasculature and number of perivascular macrophages were greater in the English CADASIL samples compared to those from the Swedish brains. Multiple approaches suggest that the Swedish family with hereditary MID suspected to be CADASIL has a different novel disorder with dissimilar pathological features and belongs to the growing number of genetically uncharacterized familial SVDs.


Assuntos
CADASIL/genética , Demência por Múltiplos Infartos/genética , Receptores Notch/genética , Adulto , Encéfalo/irrigação sanguínea , Encéfalo/ultraestrutura , Mapeamento Cromossômico/métodos , Análise Mutacional de DNA/métodos , Demência por Múltiplos Infartos/metabolismo , Demência por Múltiplos Infartos/patologia , Feminino , Humanos , Arteriosclerose Intracraniana/genética , Arteriosclerose Intracraniana/patologia , Imageamento por Ressonância Magnética , Masculino , Microcirculação/metabolismo , Pessoa de Meia-Idade , Mutação , Linhagem , Reação em Cadeia da Polimerase/métodos , Receptor Notch3 , Receptores Notch/metabolismo , Pele/ultraestrutura
13.
P N G Med J ; 50(3-4): 145-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-19583097

RESUMO

A prospective study was undertaken to document the importance of urinary tract infection (UTI) as a cause of fever without a focus (FWF) in children less than 3 years of age presenting to the Children's Outpatients Department (COPD) of Port Moresby General Hospital (PMGH). 98 children, 55 males and 43 females, with a median age of 17 months and an interquartile range of 5-31.25 months, were recruited. In addition to a history and physical examination each child had a full blood count, a malaria parasite smear, and a urine sample (obtained by clean catch or midstream methods) for dipstick testing, microscopy and culture. Blood culture was performed where practicable. Lumbar puncture and cerebrospinal fluid (CSF) examination were done only if clinically indicated. UTI was diagnosed on urine culture in 9 of the 98 children. Both urinary nitrite and leukocyte esterase tests were sensitive (89%) and specific (96%). Other causes of FWF were classified as non-specific viral infection (31 children), lower respiratory tract infection (11), malaria (7), meningitis (4), bacteraemia (1 neonate) and other or unknown causes. The finding of UTI in 9% of the children is consistent with data from other tropical countries. Checking for urinary tract infection, which can be done using noninvasive methods of urine collection, is an important part of the investigation of infants and children with FWF.


Assuntos
Febre de Causa Desconhecida/etiologia , Infecções Urinárias/complicações , Infecções Urinárias/epidemiologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Ambulatório Hospitalar/estatística & dados numéricos , Papua Nova Guiné/epidemiologia , Prevalência , Estudos Prospectivos , Urinálise
14.
J Med Genet ; 42(11): 837-46, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15792962

RESUMO

BACKGROUND: The haplotype H1 of the tau gene, MAPT, is highly associated with progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). OBJECTIVE: To investigate the pathogenic basis of this association. METHODS: Detailed linkage disequilibrium and common haplotype structure of MAPT were examined in 27 CEPH trios using validated HapMap genotype data for 24 single nucleotide polymorphisms (SNPs) spanning MAPT. RESULTS: Multiple variants of the H1 haplotype were resolved, reflecting a far greater diversity of MAPT than can be explained by the H1 and H2 clades alone. Based on this, six haplotype tagging SNPs (htSNPs) that capture 95% of the common haplotype diversity were used to genotype well characterised PSP and CBD case-control cohorts. In addition to strong association with PSP and CBD of individual SNPs, two common haplotypes derived from these htSNPs were identified that are highly associated with PSP: the sole H2 derived haplotype was underrepresented and one of the common H1 derived haplotypes was highly associated, with a similar trend observed in CBD. There were powerful and highly significant associations with PSP and CBD of haplotypes formed by three H1 specific SNPs. This made it possible to define a candidate region of at least approximately 56 kb, spanning sequences from upstream of MAPT exon 1 to intron 9. On the H1 haplotype background, these could harbour the pathogenic variants. CONCLUSIONS: The findings support the pathological evidence that underlying variations in MAPT could contribute to disease pathogenesis by subtle effects on gene expression and/or splicing. They also form the basis for the investigation of the possible genetic role of MAPT in Parkinson's disease and other tauopathies, including Alzheimer's disease.


Assuntos
Regulação da Expressão Gênica , Desequilíbrio de Ligação , Doenças Neurodegenerativas/genética , Paralisia Supranuclear Progressiva/genética , Proteínas tau/genética , Idoso , Encéfalo/patologia , Feminino , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/metabolismo , Polimorfismo de Nucleotídeo Único , Paralisia Supranuclear Progressiva/metabolismo
15.
Transl Psychiatry ; 6: e728, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26836416

RESUMO

Dementia with Lewy bodies (DLB) is the second most common form of degenerative dementia. Siblings of affected individuals are at greater risk of developing DLB, but little is known about the underlying genetic basis of the disease. We set out to determine whether mutations in known highly penetrant neurodegenerative disease genes are found in patients with DLB. Whole-exome sequencing was performed on 91 neuropathologically confirmed cases of DLB, supplemented by independent APOE genotyping. Genetic variants were classified using established criteria, and additional neuropathological examination was performed for putative mutation carriers. Likely pathogenic variants previously described as causing monogenic forms of neurodegenerative disease were found in 4.4% of patients with DLB. The APOE ɛ4 allele increased the risk of disease (P=0.0001), conferred a shorter disease duration (P=0.043) and earlier age of death (P=0.0015). In conclusion, although known pathogenic mutations in neurodegenerative disease genes are uncommon in DLB, known genetic risk factors are present in >60% of cases. APOE ɛ4 not only modifies disease risk, but also modulates the rate of disease progression. The reduced penetrance of reported pathogenic alleles explains the lack of a family history in most patients, and the presence of variants previously described as causing frontotemporal dementia suggests a mechanistic overlap between DLB and other neurodegenerative diseases.


Assuntos
Exoma/genética , Doença por Corpos de Lewy/genética , Idoso , Feminino , Humanos , Masculino
16.
Oncogene ; 8(6): 1679-83, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8502487

RESUMO

We sought sequence characteristics that might explain the apparent high recombination frequency of the 5-kb BglII segment containing M-bcr exons 1, 2 and 3, and the intron to exon 4. An Alu sequence (subfamily Sx), in 5'-->3' orientation, lay in the middle of a 3-kb region that contains the great majority of Philadelphia chromosome breakpoint sites. The breakpoint of only one out of five chronic myeloid leukemia patients, for whom the BCR breakpoint site had been sequenced, was located within this Alu. Other features of interest for recombination were a 51-bp AT-rich region close to the 3' end, six hypervariable minisatellite consensus octamers, GC[A/T]GG[A/T]GG, six lymphoid recombinase heptamer signal sequences, one nonamer and a 16-bp inverted repeat. Dot matrix comparisons of the 5-kb M-bcr sequence with a 3-kb m-bcr2 segment showed significant homology only in corresponding Alu sequences.


Assuntos
Cromossomos Humanos Par 22 , DNA de Neoplasias/genética , DNA Satélite/genética , Rearranjo Gênico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteínas Oncogênicas/genética , Oncogenes , Proteínas Tirosina Quinases , Proteínas Proto-Oncogênicas , Translocação Genética , Sequência de Bases , Éxons , Variação Genética , Humanos , Dados de Sequência Molecular , Proteínas Proto-Oncogênicas c-bcr , Recombinação Genética , Sequências Repetitivas de Ácido Nucleico , Mapeamento por Restrição
17.
Oncogene ; 6(6): 1093-5, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1829807

RESUMO

A FER-related sequence isolated from a human genomic library was found to be homologous to TRK. In situ hybridization of a 0.92 kb probe, isolated from this sequence, localized the TRK gene to the long arm of chromosome 1 within bands 1q23-1q24. This is a significantly more proximal location of TRK than the 1q32-1q41 site published recently (Miozzo et al., 1990).


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 1 , Proteínas Oncogênicas/genética , Sequência de Aminoácidos , Sequência de Bases , Sondas de DNA , Humanos , Dados de Sequência Molecular , Proto-Oncogene Mas
18.
Stroke ; 36(9): 1864-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16051894

RESUMO

BACKGROUND AND PURPOSE: The apolipoprotein E4 allele (APOE4) associates with increased dementia risk, and hypertension may associate with mild cognitive deficits. We examined whether nondemented stroke patients with (1) a prestroke history of hypertension and (2) APOE4 were more cognitively impaired at 3 months after stroke. METHODS: A total of 257 participants were genotyped and outcomes from neuropsychological evaluations analyzed using regression. RESULTS: Total Cambridge Assessment for Mental Disorders in the Elderly (CAMCOG) and speed of working memory significantly associated with hypertension. No outcomes significantly associated with APOE4. CONCLUSIONS: Subjects with prestroke hypertension had more impaired global cognition and slower access to information held in working memory.


Assuntos
Apolipoproteínas E/genética , Transtornos Cognitivos/genética , Hipertensão/genética , Hipertensão/patologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Alelos , Apolipoproteína E2 , Apolipoproteína E4 , Fibrilação Atrial/genética , Cognição , Diabetes Mellitus Tipo 2/genética , Feminino , Genótipo , Humanos , Masculino , Testes Neuropsicológicos , Análise de Regressão , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento
19.
Leukemia ; 2(2): 74-8, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3422701

RESUMO

A patient with Ph-negative chronic myeloid leukemia showed active karyotypic evolution when he entered blast crisis. One cell line, which predominated briefly in an accelerated myeloid phase, was characterized by the t(11;19)(q23;p13). Chromosome in situ hybridization demonstrated movement of the oncogene c-ets-1 from the der (11q-) to the der (19p+). The breakpoint at 19p13 was in the vicinity of the human insulin receptor gene locus (INSR). No rearrangements of the c-ets and INSR genes were found in Southern blot analyses. Myeloid lineage was indicated by cell morphology and absence of immunoglobulin JH gene rearrangement and was supported by loss of the germ line bcr-3' gene. Chromosome rearrangements involving 11q23 and movement of c-ets-1 characterize monocytic and lymphoid leukemias and have not previously been reported in myeloid blast crisis of chronic myeloid leukemia.


Assuntos
Transformação Celular Neoplásica/patologia , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 19 , Leucemia Mieloide/genética , Proto-Oncogenes , Translocação Genética , Deleção Cromossômica , Células Clonais/patologia , Clonagem Molecular , Humanos , Cariotipagem , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico
20.
Leukemia ; 13(1): 126-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10049047

RESUMO

We report a patient with Philadelphia (Ph)-positive, BCR-ABL rearrangement positive, chronic myeloid leukemia (CML) with a prolonged chronic phase of 24 years who was first prescribed alpha-2 interferon 22 years after initial diagnosis. This therapy was tolerated poorly on account of thrombocytopenia, but an eventual major cytogenetic response was followed soon afterwards by transformation to terminal acute myeloid leukemia (AML). Cytogenetic studies indicated that the transformed myeloblasts were karyotypically normal and Ph negative. Although polymerase chain reaction (PCR) analysis of total leukemic mRNA remained BCR-ABL positive, other molecular studies, including Southern blotting and fluorescent in situ hybridization (FISH) analyses, showed that myeloblasts were BCR-ABL rearrangement negative. PCR-based clonality studies using an X-chromosome-linked restriction fragment polymorphism within the phosphoglycerate kinase gene (PGK1) further showed that the Ph-negative blast cells had a different clonal origin from the Ph-positive clone of chronic phase. We suggest that cases of underlying Ph-negative leukemic transformation in Ph-positive CML warrant further study and should be considered for trial of intensive remission induction therapy as appropriate for acute leukemia.


Assuntos
Crise Blástica/diagnóstico , Bussulfano/uso terapêutico , Proteínas de Fusão bcr-abl/genética , Interferon-alfa/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Doença Aguda , Adulto , Medula Óssea/patologia , Diagnóstico Diferencial , Feminino , Rearranjo Gênico , Humanos , Hibridização in Situ Fluorescente , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Fosfoglicerato Quinase/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Cromossomo X
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