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1.
Opt Lett ; 45(17): 4790-4793, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870858

RESUMO

Optical beams carrying orbital angular momentum are a very active field of research for their prospective applications, especially at short wavelengths. We consider here such beams produced through high-harmonic generation (HHG) in a rare gas and analyze the characterization of their high-charge vortex structure by an extreme ultraviolet Hartmann wavefront sensor. We show that such HHG beams are generally composed of a set of numerous vortex modes. The sensitivity of the intensity and phase of the HHG beam to the infrared laser aberrations is investigated using a deformable mirror.

2.
Opt Lett ; 43(12): 2780-2783, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29905687

RESUMO

We demonstrate for the first time, to the best of our knowledge, the ability of extreme ultraviolet (XUV) Hartmann wavefront sensors to characterize high charge vortex beams produced by high-order harmonic generation up to the order of 25. We also show that phase matched absorption limited high harmonic generation is able to maintain the high charge vortex structure of the XUV beam even in a rather long (1 cm) generation medium.

3.
Funct Neurol ; 32(1): 28-34, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28380321

RESUMO

The aim of our study was to identify and quantify spatiotemporal and kinematic gait parameters obtained by 3D gait analysis (GA) in a group of Parkinson's disease (PD) patients compared with healthy subjects in order to investigate whether early PD patients could present an abnormal gait pattern. Forty-four patients affected by early-stage PD compared with a control group were analyzed. All participants were evaluated with 3D GA in the gait laboratory. The greatest significance in temporal parameters was found in cadence (102.46 ± 13.17 steps/min in parkinsonian patients vs 113.84 ± 4.30 steps/min in control subjects), followed by stride duration (1.19 ± 0.18 seconds right limb and 1.19 ± 0.19 seconds left limb in PD patients vs 0.426 ± 0.16 seconds right limb and 0.429 ± 0.23 seconds left limb in normal subjects) and stance duration. Marked differences were also found in the swing phase and in swing duration (p<0.05), while the stance phase was not significantly different in patients compared with healthy subjects. A statistically different velocity in PD patients (0.082 ± 0.29 m/s) vs healthy subjects (1.33 ± 0.06 m/s) was shown by spatial parameter analysis. Step width, stride length and swing velocity were highly significant parameters, as was average velocity. Our study highlighted some distinguishing characteristics of gait in early PD. Ambulation disorders may be present in the early stage of PD and their detection allows for early medical treatment and possible rehabilitation.


Assuntos
Marcha , Doença de Parkinson/fisiopatologia , Idoso , Antiparkinsonianos/uso terapêutico , Fenômenos Biomecânicos , Feminino , Humanos , Imageamento Tridimensional , Levodopa/uso terapêutico , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Caminhada
4.
Folia Neuropathol ; 54(3): 282-294, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27764521

RESUMO

INTRODUCTION: Fahr's disease is characterized by bilateral calcium deposition within the basal ganglia, cerebellar dentate nucleus and subcortical brain white matter. The main clinical manifestations are rigid or hyperkinetic syndrome, mood disorders and cognitive impairment. The correlation between neurological impairment and symmetrical basal ganglia calcification is not so frequent. Aim of the study was to report the results of neurological assessment of three sporadic cases of Fahr's disease highlighting a correlation between the clinical syndrome and neuroimaging. CASE REPORTS: Three adults of aged 32, 55 and 70, were studied. They all showed a heterogeneous clinical spectrum. One case developed neuropsychiatric symptoms, whereas the others complained of the tremorigen syndrome. Brain computed tomography scans revealed several calcifications in basal ganglia, cerebellar white matter and dentate nuclei. CONCLUSIONS: The pathogenesis of Fahr's disease is probably secondary to the dysfunction of cortico-basal connections and their interhemispheric relations. No significant correlation between calcifications and neurological symptoms is proved.


Assuntos
Doenças dos Gânglios da Base/diagnóstico , Doenças dos Gânglios da Base/metabolismo , Calcinose/diagnóstico , Calcinose/metabolismo , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/metabolismo , Adulto , Idoso , Encéfalo/patologia , Calcificação Fisiológica/fisiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico/métodos , Testes Neuropsicológicos
5.
Blood ; 93(3): 936-41, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9920843

RESUMO

Human immunodeficiency virus (HIV)-1-infected long-term nonprogressors (LT-NP) represent less than 5% of HIV-1-infected patients. In this work, we tried to understand whether combined genotypes of CCR5-triangle up32, CCR2-64I, SDF1-3'A and HLA alleles can predict the LT-NP status. Among the chemokine receptor genotypes, only the frequency of the CCR5-triangle up32 allele was significantly higher in LT-NP compared with the group of standard progressors. The predominant HLA alleles in LT-NP were HLA-A3, HLA-B14, HLA-B17, HLA-B27, HLA-DR6, and HLA-DR7. A combination of both HLA and chemokine receptor genotypes integrated in a multivariate logistic regression model showed that if a subject is heterozygous for CCR5-triangle up32 and homozygous for SDF1 wild type, his odds of being LT-NP are increased by 16-fold, by 47-fold when a HLA-B27 allele is present with HLA-DR6 absent, and by 47-fold also if at least three of the following alleles are present: HLA-A3, HLA-B14, HLA-B17, HLA-DR7. This model allowed a correct classification of 70% of LT-NPs and 81% of progressors, suggesting that the host's genetic background plays an important role in the evolution of HIV-1. The chemokine receptor and chemokine genes along with the HLA genotype can serve as predictors of HIV-1 outcome for classification of HIV-1-infected subjects as LT-NPs or progressors.


Assuntos
Quimiocinas CXC/genética , Infecções por HIV/genética , Sobreviventes de Longo Prazo ao HIV , HIV-1 , Receptores CCR5/genética , Receptores de Quimiocinas , Receptores de Citocinas/genética , Adolescente , Adulto , Alelos , Quimiocina CXCL12 , Estudos de Coortes , Progressão da Doença , Intervalo Livre de Doença , Feminino , França/epidemiologia , Predisposição Genética para Doença , Genótipo , Infecções por HIV/mortalidade , Sobreviventes de Longo Prazo ao HIV/estatística & dados numéricos , Antígenos HLA/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptores CCR2 , Deleção de Sequência
6.
AIDS ; 11(11): F73-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9302436

RESUMO

OBJECTIVE: To determine the influence of heterozygosity for the delta 32 mutant CCR-5 allele on HIV-1 disease progression. DESIGN: HIV-1 disease progression and serum viral load were analysed according to the C-C chemokine receptor (CCR)-5 genotype in 412 Caucasian patients (319 men and 93 women) with a known date of seroconversion, who were enrolled in the SEROCO cohort (median follow-up, 74 months). RESULTS: The frequency of heterozygosity for the mutant allele was 17% and did not differ according to sex or risk factor of HIV infection. Heterozygotes were significantly less likely than patients with two functional alleles to have symptomatic primary infection. Their serum viral load was lower during the 6- to 24-month plateau phase after seroconversion. This difference persisted afterwards, although the rate of decline in CD4+ cells was similar. Kaplan-Meier survival curves showed slower progression to clinical AIDS in heterozygotes during the first 7 years following infection (P < 0.02), the two curves tending to join thereafter (overall log-rank test, P = 0.17). However, the interaction term with time did not reach significance in a Cox model. The overall relative risk of progression was 0.67 (95% confidence interval, 0.38-1.18) and was not influenced by adjustment for age at seroconversion or symptomatic primary infection. After adjustment for early viral load the relative risk was 0.83. Pneumocystis carinii pneumonia and toxoplasmosis were less likely to be the first AIDS-defining illness in heterozygotes than in the other patients (0 versus 24.7% of AIDS cases, P = 0.04), despite similar management. CONCLUSION: Deletion of one CCR-5 gene allele appears to protect against HIV-1 disease progression, mainly during the early years of the infection. Heterozygosity for the deletion leads to persistently lower viral load, and also seems to protect against some opportunistic infections.


Assuntos
Infecções por HIV/genética , HIV-1 , Receptores de Citocinas/genética , Receptores de HIV/genética , Carga Viral , Infecções Oportunistas Relacionadas com a AIDS/genética , Síndrome da Imunodeficiência Adquirida/diagnóstico , Alelos , Contagem de Linfócito CD4 , Progressão da Doença , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pneumonia por Pneumocystis/diagnóstico , RNA Viral/análise , Receptores CCR5 , Fatores de Risco , Fatores Sexuais , Toxoplasmose/diagnóstico
7.
Eur Neurol ; 28(1): 30-3, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2452738

RESUMO

The main 'acute-phase proteins' were determined in serum of 20 patients with presenile Alzheimer's disease (AD) and compared with values in 18 age-matched healthy control subjects. Following parameters were evaluated: alpha 1-antitrypsin (alpha AT), haptoglobin (HPT), transferrin (TRF), acidic alpha 1-glycoprotein (A alpha G), ceruloplasmin (CER), alpha 2-macroglobulin (alpha MG), C-reactive protein (CRP), albumin (ALB), together with the immunoglobulins IgG, IgM and IgA, and some of the most significant factors of the classic (C3, C4) and alternative (properdin factor B) pathways of complement activation. The results showed a statistically significant increase in the levels of alpha AT (p less than 0.001), CER (p less than 0.001) and of all the complement factors studied (p less than 0.005). The levels of other acute-phase protein (HPT, TRF, A alpha G, alpha MG, CRP, ALB) and immunoglobulins (IgG, IgM, IgA) were similar in AD patients and normal controls. These results give rise the possibility that these elements indicate an altered immunoregulation compatible with chronic cell damage and/or chronic inflammation conditions. Moreover, the increased level of alpha AT can be related to the low production of interleukin-1 (IL-1) reported in AD, which supports the hypothesis of a relative derangement of the macrophage function in presenile AD patients.


Assuntos
Proteínas de Fase Aguda/sangue , Doença de Alzheimer/imunologia , Idoso , Proteínas do Sistema Complemento/metabolismo , Feminino , Humanos , Imunoglobulinas/metabolismo , Masculino , Pessoa de Meia-Idade
8.
Riv Neurol ; 56(6): 358-64, 1986.
Artigo em Italiano | MEDLINE | ID: mdl-3296121

RESUMO

A 30 days therapeutical trial with trazodone has been performed in 47 patients suffering from different types of tremor. No significant improvement was detected in patients suffering from parkinsonian syndromes, multiple sclerosis, psycogenic tremor and hyperthyroidism. After the double-blind trial with trazodone, a significant improvement (p less than 0.025) was, instead, evident in 5 out of 6 patients with essential tremor, while the score did not change in the 3 patients with essential tremor who were treated with placebo.


Assuntos
Trazodona/uso terapêutico , Tremor/tratamento farmacológico , Adulto , Idoso , Ensaios Clínicos como Assunto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Transtornos Somatoformes/tratamento farmacológico , Tremor/psicologia
9.
Ital J Neurol Sci ; 7(5): 537-9, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3804708

RESUMO

We report a head-injured patient in whom CT scan revealed an extracerebral hypodense fluid collection separated into two compartments by a membrane, which was probably the torn dura mater. We briefly discuss the probable pathogenetic mechanism.


Assuntos
Líquido Cefalorraquidiano , Hematoma Epidural Craniano/etiologia , Fraturas Cranianas/complicações , Adulto , Espaço Epidural , Osso Frontal/lesões , Humanos , Masculino , Osso Parietal/lesões , Espaço Subdural , Lobo Temporal/patologia , Tomografia Computadorizada por Raios X
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