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1.
Phys Rev Lett ; 123(5): 057401, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31491315

RESUMO

We show that crystal-field calculations for C_{1} point-group symmetry are possible, and that such calculations can be performed with sufficient accuracy to have substantial utility for rare-earth based quantum information applications. In particular, we perform crystal-field fitting for a C_{1}-symmetry site in ^{167}Er^{3+}:Y_{2}SiO_{5}. The calculation simultaneously includes site-selective spectroscopic data up to 20 000 cm^{-1}, rotational Zeeman data, and ground- and excited-state hyperfine structure determined from high-resolution Raman-heterodyne spectroscopy on the 1.5 µm telecom transition. We achieve an agreement of better than 50 MHz for assigned hyperfine transitions. The success of this analysis opens the possibility of systematically evaluating the coherence properties, as well as transition energies and intensities, of any rare-earth ion doped into Y_{2}SiO_{5}.

2.
J Phys Condens Matter ; 31(1): 015501, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30499454

RESUMO

We present a comprehensive spectroscopic study of C[Formula: see text] point-group symmetry sites in Sm[Formula: see text]:CaF[Formula: see text]/SrF[Formula: see text] codoped with either NaF or LiF. Data includes electron paramagnetic resonance measurements of Zeeman and hyperfine interactions for the ground state, as well as site-selective excitation and fluorescence spectroscopy up to the [Formula: see text]G[Formula: see text] multiplet. Inclusion of the EPR data allowed us to determine unique crystal-field parameters. The parameters provide information about the geometry of the sites and the nature of the interactions between the Sm[Formula: see text] dopant and the alkaline earth co-dopant.

3.
Mol Psychiatry ; 22(12): 1680-1690, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29086770

RESUMO

The epigenome is associated with biological factors, such as disease status, and environmental factors, such as smoking, alcohol consumption and body mass index. Although there is a widespread perception that environmental influences on the epigenome are pervasive and profound, there has been little evidence to date in humans with respect to environmental factors that are biologically distal. Here we provide evidence on the associations between epigenetic modifications-in our case, CpG methylation-and educational attainment (EA), a biologically distal environmental factor that is arguably among the most important life-shaping experiences for individuals. Specifically, we report the results of an epigenome-wide association study meta-analysis of EA based on data from 27 cohort studies with a total of 10 767 individuals. We find nine CpG probes significantly associated with EA. However, robustness analyses show that all nine probes have previously been found to be associated with smoking. Only two associations remain when we perform a sensitivity analysis in the subset of never-smokers, and these two probes are known to be strongly associated with maternal smoking during pregnancy, and thus their association with EA could be due to correlation between EA and maternal smoking. Moreover, the effect sizes of the associations with EA are far smaller than the known associations with the biologically proximal environmental factors alcohol consumption, body mass index, smoking and maternal smoking during pregnancy. Follow-up analyses that combine the effects of many probes also point to small methylation associations with EA that are highly correlated with the combined effects of smoking. If our findings regarding EA can be generalized to other biologically distal environmental factors, then they cast doubt on the hypothesis that such factors have large effects on the epigenome.


Assuntos
Sucesso Acadêmico , Epigênese Genética , Ilhas de CpG , Metilação de DNA , Estudos de Associação Genética , Humanos , Herança Multifatorial
4.
Displays ; 46: 16-24, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28757666

RESUMO

This paper describes an algorithm for generating a planar image that when tilted provides stereo cues to slant, without contamination from pictorial gradients. As the stimuli derived from this image are ultimately intended for use in studies of slant perception under magnification, a further requirement is that the generated image be suitable for high-definition printing or display on a monitor. A first stage generates an image consisting of overlapping edges with sufficient density that when zoomed, edges that nearly span the original scale are replaced with newly emergent content that leaves the visible edge statistics unchanged. A second stage reduces intensity clumping while preserving edges by enforcing a broad dynamic range across the image. Spectral analyses demonstrate that the low-frequency content of the resulting image, which would correspond to the pictorial cue of texture gradient changes under slant, (a) has a power fall-off deviating from 1/f noise (to which the visual system is particularly sensitive), and (b) does not offer systematic cues under changes in scale or slant. Two behavioral experiments tested whether the algorithm generates stimuli that offer cues to slant under stereo viewing only, and not when disparities are eliminated. With a particular adjustment of dynamic range (and nearly so with the other version that was tested), participants viewing without stereo cues were essentially unable to discriminate slanted from flat (frontal) stimuli, and when slant was reported, they failed to discriminate its direction. In contrast, non-stereo viewing of a control stimulus with pictorial cues, as well as stereoscopic observation, consistently allowed participants to perceive slant correctly. Experiment 2 further showed that these results generalized across a population of different stimuli from the same generation process and demonstrated that the process did not substitute biased slant cues.

5.
Transl Psychiatry ; 6(12): e983, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27959337

RESUMO

The blood-brain barrier separates circulating blood from the central nervous system (CNS). The scope of this barrier is not fully understood which limits our ability to relate biological measurements from peripheral to central phenotypes. For example, it is unknown to what extent gene expression levels in peripheral blood are reflective of CNS metabolism. In this study, we examine links between central monoamine metabolite levels and whole-blood gene expression to better understand the connection between peripheral systems and the CNS. To that end, we correlated the prime monoamine metabolites in cerebrospinal fluid (CSF) with whole-genome gene expression microarray data from blood (N=240 human subjects). We additionally applied gene-enrichment analysis and weighted gene co-expression network analyses (WGCNA) to identify modules of co-expressed genes in blood that may be involved with monoamine metabolite levels in CSF. Transcript levels of two genes were significantly associated with CSF serotonin metabolite levels after Bonferroni correction for multiple testing: THAP7 (P=2.8 × 10-8, ß=0.08) and DDX6 (P=2.9 × 10-7, ß=0.07). Differentially expressed genes were significantly enriched for genes expressed in the brain tissue (P=6.0 × 10-52). WGCNA revealed significant correlations between serotonin metabolism and hub genes with known functions in serotonin metabolism, for example, HTR2A and COMT. We conclude that gene expression levels in whole blood are associated with monoamine metabolite levels in the human CSF. Our results, including the strong enrichment of brain-expressed genes, illustrate that gene expression profiles in peripheral blood can be relevant for quantitative metabolic phenotypes in the CNS.


Assuntos
Monoaminas Biogênicas/líquido cefalorraquidiano , Perfilação da Expressão Gênica , Adolescente , Adulto , Idoso , Encéfalo/metabolismo , Endofenótipos , Feminino , Ácido Homovanílico/líquido cefalorraquidiano , Humanos , Ácido Hidroxi-Indolacético/líquido cefalorraquidiano , Masculino , Metoxi-Hidroxifenilglicol/líquido cefalorraquidiano , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Valores de Referência , Serotonina/líquido cefalorraquidiano , Serotonina/genética , Adulto Jovem
6.
Am J Transplant ; 15(6): 1605-14, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25828101

RESUMO

Early hepatic allograft dysfunction (EAD) manifests posttransplantation with high serum transaminases, persistent cholestasis, and coagulopathy. The biological mechanisms are poorly understood. This study investigates the molecular mechanisms involved in EAD and defines a gene expression signature revealing different biological pathways in subjects with EAD from those without EAD, a potential first step in developing a molecular classifier as a potential clinical diagnostic. Global gene expression profiles of 30 liver transplant recipients of deceased donor grafts with EAD and 26 recipients without graft dysfunction were investigated using microarrays of liver biopsies performed at the end of cold storage and after graft reperfusion prior to closure. Results reveal a shift in inflammatory and metabolic responses between the two time points and differences between EAD and non-EAD. We identified relevant pathways (PPARα and NF-κB) and targets (such as CXCL1, IL1, TRAF6, TIPARP, and TNFRSF1B) associated with the phenotype of EAD. Preliminary proof of concept gene expression classifiers that distinguish EAD from non-EAD patients, with Area Under the Curve (AUC) >0.80 were also identified. This data may have mechanistic and diagnostic implications for EAD.


Assuntos
Testes Genéticos , Rejeição de Enxerto/genética , Transplante de Fígado , Fígado/fisiopatologia , Transcriptoma/genética , Adulto , Idoso , Aloenxertos , Biópsia , Feminino , Humanos , Fígado/patologia , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , PPAR alfa/genética , Doadores de Tecidos , Transcrição Gênica/genética , Transplantados
7.
Mol Psychiatry ; 20(12): 1499-507, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25623945

RESUMO

Reduced expression of the Gad1 gene-encoded 67-kDa protein isoform of glutamic acid decarboxylase (GAD67) is a hallmark of schizophrenia. GAD67 downregulation occurs in multiple interneuronal sub-populations, including the parvalbumin-positive (PVALB+) cells. To investigate the role of the PV-positive GABAergic interneurons in behavioral and molecular processes, we knocked down the Gad1 transcript using a microRNA engineered to target specifically Gad1 mRNA under the control of Pvalb bacterial artificial chromosome. Verification of construct expression was performed by immunohistochemistry. Follow-up electrophysiological studies revealed a significant reduction in γ-aminobutyric acid (GABA) release probability without alterations in postsynaptic membrane properties or changes in glutamatergic release probability in the prefrontal cortex pyramidal neurons. Behavioral characterization of our transgenic (Tg) mice uncovered that the Pvalb/Gad1 Tg mice have pronounced sensorimotor gating deficits, increased novelty-seeking and reduced fear extinction. Furthermore, NMDA (N-methyl-d-aspartate) receptor antagonism by ketamine had an opposing dose-dependent effect, suggesting that the differential dosage of ketamine might have divergent effects on behavioral processes. All behavioral studies were validated using a second cohort of animals. Our results suggest that reduction of GABAergic transmission from PVALB+ interneurons primarily impacts behavioral domains related to fear and novelty seeking and that these alterations might be related to the behavioral phenotype observed in schizophrenia.


Assuntos
Comportamento Animal , Glutamato Descarboxilase/genética , Interneurônios/metabolismo , Parvalbuminas/metabolismo , Esquizofrenia/genética , Animais , Encéfalo/fisiologia , Modelos Animais de Doenças , Eletrofisiologia , Comportamento Exploratório , Medo , Inativação Gênica , Ketamina/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Transgênicos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Filtro Sensorial/genética , Transmissão Sináptica
8.
Am J Transplant ; 14(5): 1164-72, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24725967

RESUMO

There are no minimally invasive diagnostic metrics for acute kidney transplant rejection (AR), especially in the setting of the common confounding diagnosis, acute dysfunction with no rejection (ADNR). Thus, though kidney transplant biopsies remain the gold standard, they are invasive, have substantial risks, sampling error issues and significant costs and are not suitable for serial monitoring. Global gene expression profiles of 148 peripheral blood samples from transplant patients with excellent function and normal histology (TX; n = 46), AR (n = 63) and ADNR (n = 39), from two independent cohorts were analyzed with DNA microarrays. We applied a new normalization tool, frozen robust multi-array analysis, particularly suitable for clinical diagnostics, multiple prediction tools to discover, refine and validate robust molecular classifiers and we tested a novel one-by-one analysis strategy to model the real clinical application of this test. Multiple three-way classifier tools identified 200 highest value probesets with sensitivity, specificity, positive predictive value, negative predictive value and area under the curve for the validation cohort ranging from 82% to 100%, 76% to 95%, 76% to 95%, 79% to 100%, 84% to 100% and 0.817 to 0.968, respectively. We conclude that peripheral blood gene expression profiling can be used as a minimally invasive tool to accurately reveal TX, AR and ADNR in the setting of acute kidney transplant dysfunction.


Assuntos
Biomarcadores/sangue , Perfilação da Expressão Gênica , Rejeição de Enxerto/sangue , Rejeição de Enxerto/classificação , Falência Renal Crônica/cirurgia , Transplante de Rim , Complicações Pós-Operatórias/genética , Adulto , Área Sob a Curva , Reações Falso-Negativas , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Humanos , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Complicações Pós-Operatórias/sangue , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade
9.
Vet Clin Pathol ; 43(1): 15-23, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24405452

RESUMO

BACKGROUND: Greyhounds have several hematologic variables that are outside of the respective reference intervals of other dog breeds. In addition, increases in HCT, total protein and HGB concentration, and RBC and WBC counts occur immediately after exercise; these values return to resting values within a few hour after racing. OBJECTIVE: This study evaluated the effects of exercise on the concentration of reticulocytes in circulating blood in racing Greyhounds. We hypothesized that reticulocyte numbers are significantly increased immediately after a race, and return to baseline within one to 2 h postrace. METHODS: Fifty actively racing Greyhounds at the Wheeling Island Racetrack and Casino were included in the study. Samples were collected by jugular venipuncture one day prior to racing at the kennel (resting), immediately after racing, and one to 2 h after the race (recovery). Reticulocyte counts were determined with an IDEXX ProCyte Dx Hematology Analyzer (IDEXX Laboratories, Inc., Westbrook, ME, USA). Due to a nonparametric distribution, the results were statistically compared using the Friedman test. RESULTS: Reticulocyte concentrations were significantly different among the 3 sample collection times (P < .0001). There was a significant increase in reticulocyte concentration immediately after racing (P < .001); one to 2 h after racing, the reticulocyte numbers decreased significantly (P < .001) to counts comparable to resting samples. CONCLUSION: The increase in reticulocyte concentration is probably related to splenic contraction secondary to the release of catecholamines, although premature bone marrow release could also account for these changes. Thus, it is important to consider a Greyhound's activity and degree of excitement when interpreting selected hematologic data in a clinical setting.


Assuntos
Cães/sangue , Condicionamento Físico Animal/fisiologia , Reticulócitos/fisiologia , Animais , Cães/fisiologia , Feminino , Testes Hematológicos/veterinária , Masculino , Valores de Referência , Contagem de Reticulócitos/veterinária , Fatores de Tempo , West Virginia
10.
Mol Psychiatry ; 19(5): 580-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24322205

RESUMO

Gamma-aminobutyric acid (GABA)-ergic disturbances are hallmark features of schizophrenia and other neuropsychiatric disorders and encompass multiple interneuronal cell types. Using bacterial artificial chromosome-driven, miRNA silencing technology we generated transgenic mouse lines that suppress glutamic acid decarboxylase 1 (GAD1) in either cholecystokinin (CCK)- or neuropeptide Y (NPY)-expressing interneurons. In situ lipidomic and proteomic analyses on brain tissue sections revealed distinct, brain region-specific profiles in each transgenic line. Behavioral analyses revealed that suppression of GAD1 in CCK+ interneurons resulted in locomotor and olfactory sensory changes, whereas suppression in NPY+ interneurons affected anxiety-related behaviors and social interaction. Both transgenic mouse lines had altered sensitivity to amphetamine albeit in opposite directions. Together, these data argue that reduced GAD1 expression leads to altered molecular and behavioral profiles in a cell type-dependent manner, and that these subpopulations of interneurons are strong and opposing modulators of dopamine system function. Furthermore, our findings also support the hypothesis that neuronal networks are differentially controlled by diverse inhibitory subnetworks.


Assuntos
Comportamento/fisiologia , Colecistocinina/metabolismo , Glutamato Descarboxilase/metabolismo , Interneurônios/fisiologia , Neuropeptídeo Y/metabolismo , Ácido gama-Aminobutírico/metabolismo , Anfetamina/farmacologia , Animais , Ansiedade/fisiopatologia , Encéfalo/fisiologia , Estimulantes do Sistema Nervoso Central/farmacologia , Colecistocinina/genética , Glutamato Descarboxilase/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Neuropeptídeo Y/genética , Percepção Olfatória/fisiologia , Proteômica/métodos , Comportamento Social
11.
Transl Psychiatry ; 3: e311, 2013 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-24105442

RESUMO

Studying monoaminergic seasonality is likely to improve our understanding of neurobiological mechanisms underlying season-associated physiological and pathophysiological behavior. Studies of monoaminergic seasonality and the influence of the serotonin-transporter-linked polymorphic region (5-HTTLPR) on serotonin seasonality have yielded conflicting results, possibly due to lack of power and absence of multi-year analyses. We aimed to assess the extent of seasonal monoamine turnover and examined the possible involvement of the 5-HTTLPR. To determine the influence of seasonality on monoamine turnover, 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) were measured in the cerebrospinal fluid of 479 human subjects collected during a 3-year period. Cosine and non-parametric seasonal modeling were applied to both metabolites. We computed serotonin (5-HT) seasonality values and performed an association analysis with the s/l alleles of the 5-HTTLPR. Depressive symptomatology was assessed using the Beck Depression Inventory-II. Circannual variation in 5-HIAA fitted a spring-peak cosine model that was significantly associated with sampling month (P=0.0074). Season of sampling explained 5.4% (P=1.57 × 10(-7)) of the variance in 5-HIAA concentrations. The 5-HTTLPR s-allele was associated with increased 5-HIAA seasonality (standardized regression coefficient=0.12, P=0.020, N=393). 5-HIAA seasonality correlated with depressive symptoms (Spearman's rho=0.13, P=0.018, N=345). In conclusion, we highlight a dose-dependent association of the 5-HTTLPR with 5-HIAA seasonality and a positive correlation between 5-HIAA seasonality and depressive symptomatology. The presented data set the stage for follow-up in clinical populations with a role for seasonality, such as affective disorders.


Assuntos
Depressão/líquido cefalorraquidiano , Ácido Homovanílico/líquido cefalorraquidiano , Ácido Hidroxi-Indolacético/líquido cefalorraquidiano , Estações do Ano , Serotonina/líquido cefalorraquidiano , Adulto , Alelos , Depressão/metabolismo , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Análise de Regressão , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética
12.
Am J Transplant ; 11(9): 1972-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21794091

RESUMO

Chronic kidney disease (CKD) occurs frequently after liver transplantation (LT) and is associated with significant morbidity and mortality. Thus, there is a pressing need to identify characteristics and biomarkers diagnostic of CKD to enable early diagnosis allowing preemptive interventions, as well as mechanistic insights into the progression from kidney injury to irreversible kidney failure. We analyzed 342 patients who had baseline glomerular filteration rate (GFR) >60 at the time of LT and are now >3 years post-LT. Risk factors for post-LT CKD were compared between three different groups defined by current GFR: >90 (n = 40), 60-90 (n = 146) and <60 (n = 156) mL/min. Age, cyclosporine use and pre-LT GFR were independently associated with new onset CKD. A subset (n = 64) without viral/immune disease or graft dysfunction underwent multianalyte plasma proteomic evaluations for correlation with CKD. Plasma proteomic analysis of two independent cohorts, test (n = 22) and validation (n = 42), identified 10 proteins highly associated with new onset CKD. In conclusion, we have identified clinical characteristics and a unique plasma proteomic signature correlating with new onset CKD after LT. These preliminary results are currently being validated in a prospective, multicenter study to determine if this signature precedes the onset of CKD and resolves with early interventions aimed at preserving kidney function.


Assuntos
Biomarcadores/sangue , Proteínas Sanguíneas/metabolismo , Falência Renal Crônica/sangue , Transplante de Fígado/efeitos adversos , Proteômica , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/fisiopatologia , Masculino , Pessoa de Meia-Idade
13.
Transplant Proc ; 42(6): 2287-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20692464

RESUMO

Ischemia/reperfusion (I/R) injury is a serious condition that results from some surgical procedures, including intestinal transplantation. Ischemic postconditioning is defined as brief periods of reperfusion alternating with reocclusion applied during the early minutes after reperfusion. The objective of this study was to investigate the effect of ischemic postconditioning before small bowel autotransplantation. Total orthotopic intestinal autotransplantation was performed in 30 white domestic pigs. Grafts were stored in cold University of Wisconsin solution for 1, 3, or 6 hours. Duration of reperfusion was 3 hours in all grafts. Before reperfusion, the intestine was postconditioned via 3 cycles of ischemia for 30 seconds and reperfusion for 30 seconds (ischemic postconditioning protocol). Tissue from the small intestine was obtained after laparotomy (control group) and at the end of reperfusion periods. To monitor oxidative stress, tissue concentrations of malondialdehyde and reduced glutathione, and activity of superoxide dismutase were determined at spectrophotometry. Tissue damage on sections stained with hematoxylin- eosin was evaluated using a quantitative method (Scion Image software; Scion Corp, Frederick, Maryland). Our results demonstrated that ischemic postconditioning significantly decreased the reperfusion-ended lipid peroxidation value (mean +/- SEM, 142.0 +/- 7.1 micromol/g vs 125.0 +/- 2.1 micromol/g; P < .05). Moreover, the capacity and activity of endogenous antioxidant protective systems (glutathione 789+/-8.0 micromol/g vs 934 +/- 5.7 micromol/g, and superoxide dismutase 110 +/- 9 IU/g vs 126 +/- 4 IU/g; P < .05) remained higher in the ischemic postconditioning groups compared with tissues without ischemic postconditioning. At quantitative analysis, tissue injury was increased by the duration of cold preservation. The greatest injury was observed in the mucosal and submucosal layers and in the depth of crypts after 6 hours of preservation. Ischemic postconditioning significantly decreased intestinal wall injury in each group (P < .05). It was concluded that ischemic postconditioning before reperfusion mitigated oxidative stress and histologic damage during small bowel autotransplantation.


Assuntos
Intestino Delgado/transplante , Pós-Condicionamento Isquêmico/métodos , Animais , Temperatura Baixa , Glutationa/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/irrigação sanguínea , Intestino Delgado/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Músculo Liso/metabolismo , Preservação de Órgãos/métodos , Superóxido Dismutase/metabolismo , Suínos , Transplante Autólogo
14.
Mol Psychiatry ; 15(10): 987-95, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20125089

RESUMO

In schizophrenia, glutamic acid decarboxylase 1 (GAD1) disturbances are robust, consistently observed, cell-type specific and represent a core feature of the disease. In addition, neuropeptide Y (NPY), which is a phenotypic marker of a sub-population of GAD1-containing interneurons, has shown reduced expression in the prefrontal cortex in subjects with schizophrenia, suggesting that dysfunction of the NPY+ cortical interneuronal sub-population might be a core feature of this devastating disorder. However, modeling gene expression disturbances in schizophrenia in a cell type-specific manner has been extremely challenging. To more closely mimic these molecular and cellular human post-mortem findings, we generated a transgenic mouse in which we downregulated GAD1 mRNA expression specifically in NPY+ neurons. This novel, cell type-specific in vivo system for reducing gene expression uses a bacterial artificial chromosome (BAC) containing the NPY promoter-enhancer elements, the reporter molecule (eGFP) and a modified intron containing a synthetic microRNA (miRNA) targeted to GAD1. The animals of isogenic strains are generated rapidly, providing a new tool for better understanding the molecular disturbances in the GABAergic system observed in complex neuropsychiatric disorders such as schizophrenia. In the future, because of the small size of the silencing miRNAs combined with our BAC strategy, this method may be modified to allow generation of mice with simultaneous silencing of multiple genes in the same cells with a single construct, and production of splice-variant-specific knockdown animals.


Assuntos
Cromossomos Artificiais Bacterianos , Modelos Animais de Doenças , Inativação Gênica , Camundongos Transgênicos , MicroRNAs/genética , Esquizofrenia/genética , Processamento Alternativo , Animais , Encefalopatias/genética , Encefalopatias/fisiopatologia , Regulação da Expressão Gênica/fisiologia , Glutamato Descarboxilase/genética , Células HEK293 , Humanos , Camundongos , Neuropeptídeo Y/genética , Esquizofrenia/fisiopatologia
16.
Int Endod J ; 42(11): 1032-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19825038

RESUMO

AIM: To determine the influence of solvents on gutta-percha and sealer remaining on root canal walls and in dentinal tubules. METHODOLOGY: The root canals of 70 teeth were prepared chemomechanically to apical size 40. In group 1 (n = 10; control group), the canals remained unfilled. In groups 2-4 (n = 20 each), the canals were filled using lateral compaction with gutta-percha and sealer. Removal of root fillings was undertaken after 2 weeks using Gates Glidden burs and hand files without solvent (group 2), with eucalyptol (60 microL; group 3) and with chloroform (60 microL; group 4) to size 50. After further irrigation using sodium hypochlorite and ethylenediaminetetraacetic acid, the roots were split, photographed and scanning electron microscopy (SEM) was performed. The number of filled dentinal tubules (SEM) and the surface covered by root filling remnants (photographs) were evaluated for the coronal, middle and apical third of each root half. Statistical analysis was performed via mixed model for clustered data followed by Tukey's test. RESULTS: After pooling the results of all thirds of the canal, open tubules were more prevalent in the control group, followed by the nonsolvent group, the eucalyptol group and the chloroform group (P < 0.05 between all groups). Less surface was covered by root filling remnants in the nonsolvent group than in the eucalyptol group and the chloroform group (P < 0.05); again, fewer remnants were found in the control group than in all other groups (P < 0.05). CONCLUSIONS: Solvents led to more gutta-percha and sealer remnants on root canal walls and inside dentinal tubules.


Assuntos
Descolagem Dentária/métodos , Cavidade Pulpar/ultraestrutura , Dentina/ultraestrutura , Preparo de Canal Radicular/métodos , Solventes , Clorofórmio , Dente Canino , Cicloexanóis , Eucaliptol , Guta-Percha , Humanos , Incisivo , Microscopia Eletrônica de Varredura , Monoterpenos , Retratamento , Materiais Restauradores do Canal Radicular
17.
Clin Radiol ; 64(10): 972-82, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19748002

RESUMO

AIM: To evaluate whether computer-aided detection (CAD) as a second reader using perspective filet view [three-dimensional (3D) filet] improves the performance of inexperienced readers at computed tomography colonography (CTC) compared with unassisted 3D filet and unassisted two-dimensional (2D) CTC. MATERIAL AND METHODS: Fifty symptomatic patients underwent CTC and same-day colonoscopy with segmental unblinding. Two inexperienced readers read the CTC studies on 3D filet and 2D several weeks apart. Four months later, readers re-read the cases only evaluating CAD marks using 3D filet. Suspicious CAD marks not previously described on 3D filet were recorded. Jackknife free-response receiver operating characteristic (JAFROC-1) analysis was used to compare the observers' performances in detecting lesions with 3D filet, 2D and 3D filet with CAD. RESULTS: One hundred and three lesions > or =3mm were detected at colonoscopy with segmental unblinding. CAD alone had a sensitivity of 73% (75/103) at a mean false-positive rate per patient of 12.8 in supine and 11.4 in prone. For inexperienced readers sensitivities with 3D filet with CAD were 58% (60/103) and 48% (50/103) with an improvement of 14-16 percentage points (p<0.05) compared with 2D and of 10-11 percentage points (p<0.05) compared with 3D filet. For inexperienced readers, the false-positive rate was 25-41% and 71-200% higher with 3D filet with CAD compared with 3D filet and 2D, respectively. JAFROC-1 analysis showed no significant differences in per-lesion overall performance among reading modes (p=0.8). CONCLUSION: CAD applied as a second reader using 3D filet increased both sensitivity and the number of false positives by inexperienced readers compared with 3D filet and 2D, thus not improving overall performance, i.e., the ability to distinguish between lesions and non-lesions.


Assuntos
Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada , Colonoscopia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Competência Clínica , Colonografia Tomográfica Computadorizada/métodos , Colonografia Tomográfica Computadorizada/estatística & dados numéricos , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Software
18.
Acta Radiol ; 50(3): 244-55, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19235581

RESUMO

BACKGROUND: "Perspective-filet view" is a novel three-dimensional (3D) viewing technique for computed tomography colonography (CTC). Studies with experienced readers have shown a sensitivity for perspective-filet view similar to that of 2D or 3D endoluminal fly-through in detection of colorectal lesions. It is not known whether perspective-filet view, compared to axial images, improves lesion detection by inexperienced readers. PURPOSE: To compare primary 3D analysis using perspective-filet view (3D Filet) with primary 2D analysis, as used by inexperienced CTC readers. Secondary aims were to compare lesion detection by 3D Filet when used by experienced and inexperienced readers, and to evaluate the effect of combined 3D Filet + 2D analysis. MATERIAL AND METHODS: Fifty symptomatic patients were prospectively enrolled. An experienced reader performed 3D Filet analysis followed by complete 2D analysis (3D Filet + 2D), before colonoscopy with segmental unblinding. Two inexperienced readers (readers 2 and 3), blinded to CTC and colonoscopy findings, retrospectively performed 3D Filet analysis and, after 5 weeks, 2D analysis. True positives >or=6 mm detected by the inexperienced readers with 3D Filet and/or 2D were combined to obtain 3D Filet + 2D. RESULTS: Colonoscopy revealed 116 lesions: 16 lesions >or=10 mm, 19 lesions 6-9 mm, and 81 lesions or=6 mm with 3D Filet and 3D Filet + 2D were 77% and 83%, respectively. For the inexperienced readers, sensitivities for lesions >or=6 mm with 3D Filet and 2D were 51% and 57% (reader 2) and 40% and 43% (reader 3), respectively. There was no significant difference between 3D Filet and 2D regarding sensitivity and reading time. For lesions >or=6 mm, 3D Filet + 2D improved the sensitivity of reader 2 to 63% and of reader 3 to 51%. CONCLUSION: Lesion detection by inexperienced readers using perspective-filet view is comparable to that obtained by 2D. Lesion detection improves by combining 3D Filet + 2D, but not to the level of an experienced reader.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenoma/diagnóstico por imagem , Adenoma/epidemiologia , Competência Clínica , Pólipos do Colo/diagnóstico por imagem , Pólipos do Colo/epidemiologia , Colonografia Tomográfica Computadorizada/métodos , Colonografia Tomográfica Computadorizada/estatística & dados numéricos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/epidemiologia , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Imageamento Tridimensional/métodos , Imageamento Tridimensional/estatística & dados numéricos , Radiologia/educação , Adenocarcinoma/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Colonoscopia , Meios de Contraste/administração & dosagem , Educação Médica Continuada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Sensibilidade e Especificidade , Software , Estudos de Tempo e Movimento , Ácidos Tri-Iodobenzoicos
19.
Heredity (Edinb) ; 101(5): 416-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18648385

RESUMO

In this study, we examine the frequency of a 900 kb inversion at 17q21.3 in the Gypsy and Caucasian populations of Hungary, which may reflect the Asian origin of Gypsy populations. Of the two haplotypes (H1 and H2), H2 is thought to be exclusively of Caucasian origin, and its occurrence in other racial groups is likely to reflect admixture. In our sample, the H1 haplotype was significantly more frequent in the Gypsy population (89.8 vs 75.5%, P<0.001) and was in Hardy-Weinberg disequilibrium (P=0.017). The 17q21.3 region includes the gene of microtubule-associated protein tau, and this result might imply higher sensitivity to H1 haplotype-related multifactorial tauopathies among Gypsies.


Assuntos
Povo Asiático/genética , Variação Genética , Genoma Humano , Roma (Grupo Étnico)/genética , População Branca/genética , Proteínas tau/genética , Cromossomos Humanos Par 17/genética , Haplótipos , Humanos
20.
Clin Hemorheol Microcirc ; 39(1-4): 79-85, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18503113

RESUMO

After revascularization of an acute arterial occlusion the development of a serious ischaemic-reperfusion injury is a menacing challenge and a hard task in peripheral vascular surgery. A whale of evidences point to oxidative stress, as an important trigger, in the complex chain of events leading to reperfusion injury. In the present study authors aimed to examine oxidative stress parameters, antioxidant-prooxidant state and leukocyte adhesion molecules (CD11a and CD18) expression following acute revascularization surgery of lower limb.10 patients were examined in the prospective randomized study. Peripheral blood sample was collected in ischaemic period, and after reperfusion in the 2nd and 24th hours, and on 7th day. Superoxide-dismutase activity, reduced glutathion concentration and leukocytes free radical production were measured. The degree of lipidperoxidation was marked with the quantity of malondialdehyde. The expressions of adhesion molecules were measured with flowcytometry.The speed and rate of free radical production significantly increased in the early reperfusion (p<0.05). The level of antioxidant enzymes decreased after revascularization. The CD11a and CD18 expression of the granulocytes significantly (p<0.05) decreased right after the revascularization, but with a gradual elevation until the 7th day they exceed the ischaemic value. Our results showed a time specific turnover of the sensitive antioxidant-prooxidant balance after revascularization operation.


Assuntos
Inflamação , Extremidade Inferior/patologia , Traumatismo por Reperfusão , Procedimentos Cirúrgicos Vasculares , Antígeno CD11a/biossíntese , Antígenos CD18/biossíntese , Radicais Livres , Glutationa/metabolismo , Granulócitos/citologia , Humanos , Leucócitos/citologia , Leucócitos/metabolismo , Peroxidação de Lipídeos , Estresse Oxidativo , Estudos Prospectivos , Superóxido Dismutase/metabolismo
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