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1.
Data Brief ; 48: 109105, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37095754

RESUMO

The data presented in this article are related to the research paper entitled "Observation of night-time emissions of the Earth in the near UV range from the International Space Station with the Mini-EUSO detector" (Remote Sensing of Environment, Volume 284, January 2023, 113336, https://doi.org/10.1016/j.rse.2022.113336). The data have been acquired with the Mini-EUSO detector, an UV telescope operating in the range 290-430 nm and located inside the International Space Station. The detector was launched in August 2019, and it has started operations from the nadir-facing UV-transparent window in the Russian Zvezda module in October 2019. The data presented here refer to 32 sessions acquired between 2019-11-19 and 2021-05-06. The instrument consists of a Fresnel-lens optical system and a focal surface composed of 36 multi-anode photomultiplier tubes, each with 64 channels, for a total of 2304 channels with single photon counting sensitivity. The telescope, with a square field-of-view of 44°, has a spatial resolution on the Earth surface of 6.3 km and saves triggered transient phenomena with a temporal resolution of 2.5 µs and 320 µs. The telescope also operates in continuous acquisition at a 40.96 ms scale. In this article, large-area night-time UV maps obtained processing the 40.96 ms data, taking averages over regions of some specific geographical areas (e.g., Europe, North America) and over the entire globe, are presented. Data are binned into 0.1° × 0.1° or 0.05° × 0.05° cells (depending on the scale of the map) over the Earth's surface. Raw data are made available in the form of tables (latitude, longitude, counts) and .kmz files (containing the .png images). These are - to the best of our knowledge - the highest sensitivity data in this wavelength range and can be of use to various disciplines.

2.
Rev Sci Instrum ; 92(5): 055108, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243302

RESUMO

Red, green, blue color photography is a mature technology and a powerful tool for the evaluation and understanding of the way an object reflects light and its related optical properties, but color photography fails to give a complete picture of these effects due to its inherent lack of spectral resolution. In this work, we update the L'OREAL reference device for skin color measurement, the Chromasphere, by replacing its current color camera system with an imaging spectrometer. This imaging spectrometer must provide a spatial resolution on par with the previous color cameras and a spectral resolution commensurate with a spectroradiometer while also achieving a time resolution suitable for in vivo studies of the human face. Due to these requirements, common spatial scanning techniques are not suitable for this application, and so we utilized a spectral-scanning approach based on a tunable liquid-crystal birefringent filter. We present the design and performance tests of a working prototype that is capable of measuring the spectrum in each of 4 MP with a nominal spectral resolution of 10 nm across the wavelength range from 420 to 730 nm in a total imaging time of less than 10 s. We cross-compared the spectral and color measurements obtained with this prototype, an industry-standard spectroradiometer, and a charge-coupled device color camera in order to assess the prototype's performance, and the results of this comparison show that our prototype is capable of taking spectral measurements near enough in quality to those of a spectroradiometer to successfully bridge the divide between such devices and conventional color cameras. Doing so, this instrument opens new possibilities for studies of complex in vivo phenomena that neither non-imaging spectrometers nor conventional cameras can pursue.


Assuntos
Fotografação
3.
Sci Rep ; 7(1): 5440, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28710357

RESUMO

While the direct physical impact on seabed biota is well understood, no studies have defined thresholds to inform an ecosystem-based approach to managing fishing impacts. We addressed this knowledge gap using a large-scale experiment that created a controlled gradient of fishing intensity and assessed the immediate impacts and short-term recovery. We observed a mosaic of taxon-specific responses at various thresholds. The lowest threshold of significant lasting impact occurred between 1 and 3 times fished and elicited a decrease in abundance of 39 to 70% for some sessile epifaunal organisms (cnidarians, bryozoans). This contrasted with significant increases in abundance and/or biomass of scavenging species (epifaunal echinoderms, infaunal crustaceans) by two to four-fold in areas fished twice and more. In spite of these significant specific responses, the benthic community structure, biomass and abundance at the population level appeared resilient to fishing. Overall, natural temporal variation in community metrics exceeded the effects of fishing in this highly dynamic study site, suggesting that an acute level of disturbance (fished over six times) would match the level of natural variation. We discuss the implications of our findings for natural resources management with respect to context-specific human disturbance and provide guidance for best fishing practices.


Assuntos
Biota/fisiologia , Conservação dos Recursos Naturais/métodos , Pesqueiros/estatística & dados numéricos , Peixes/fisiologia , Cadeia Alimentar , Animais , Biomassa , Briozoários/fisiologia , Cnidários/fisiologia , Crustáceos/fisiologia , Equinodermos/fisiologia , Ecossistema , Humanos , Densidade Demográfica
4.
Biofactors ; 18(1-4): 277-81, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14695944

RESUMO

Neurodegenerative Diseases represent the most common cause of Dementia, about 5-10% of the population aged above 65 years and about 30% above 80 years. A study about Apo-E alleles, Coenzyme Q and Vitamins E as biological indicators was performed in plasma samples of patients aged from 30 to 85 years, affected by Neurodegenerative Diseases. The results were compared with control subjects of approximately the same ages as the reference group. A frequency of 21.7% of epsilon4 allele in control group was estimated, against 15.8% observed in patients. The frequency of epsilon2 and epsilon3 alleles was 13.0% and 65.2% in the control group against 10.5% and 73.7% in patients. No significant differences were observed between the frequency of epsilon3/epsilon3 genotype and epsilon3/epsilon4 genotype in the control group compared to patients' group. The frequencies observed in epsilon2/epsilon3 genotype groups were 8.7% vs 15.8% and of e2/e4 genotype 17.4% vs 5.3%. The epsilon2/epsilon2 and epsilon4/epsilon4 genotypes were not identified in any groups. Plasma CoQ10 concentrations were similar in patient and control groups and no differences were found even taking into account the distribution of male and female subjects in the two groups. Also, vitamin E did not provide evidence of any differences between groups and the analysis among sexes revealed that again vitamin E concentrations were similar in between subgroups.


Assuntos
Alelos , Apolipoproteínas E/genética , Ubiquinona/sangue , Vitamina E/sangue , Idoso , Apolipoproteína E2 , Apolipoproteína E3 , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
5.
Parasite ; 1(3): 219-26, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9140488

RESUMO

The schizogony of malarial parasite is a typical cyclic phenomenon where the different stages of parasite development appear at regular time intervals. Each of the stages is specifically sensitive to different antimalarial drugs. Knowledge of the details of the cycle, drug susceptibility and the pharmacokinetics of drugs, could allow the improvement of drug action by the chronotherapeutic approach: treatment at the time of appearance of the drug sensitive stage with a drug that displays rapid pharmacokinetics. Since murine malarias serve as preferable models for in vivo drug testing, the pharmacokinetics of subcutaneously (sc) administered chloroquine (CQ) were tested in the whole blood of healthy mice and in animals slightly (1.5-3.5% parasitemia) or heavily infected (21-25% parasitemia) with Plasmodium chabaudi chabaudi. The half-time of absorption was around 5 min and almost independent of parasitemia. The apparent half-time of drug concentration decay was around 40 min in healthy animals, about 90 min at low parasitemia and about 410 min in heavy infection, indicating that the concentration of CQ is a typical spike, that is prolonged by asymptomatic disease, and considerably more by the active accumulation of CQ in infected cells. The latter is confirmed by the 3-fold higher peak blood [CQ] at the trophozoite stage and < 1.5-fold increase during schizogony. In conjunction with our previous experiments which showed that a single sc injection of 5 mg/kg CQ is sufficient to eliminate the drug susceptible mid-term trophozoite stage, the present results seem to justify to propose the chronotherapeutic approach for the treatment of malaria.


Assuntos
Antimaláricos/farmacocinética , Cloroquina/farmacocinética , Malária/metabolismo , Parasitemia/metabolismo , Plasmodium chabaudi , Animais , Antimaláricos/administração & dosagem , Cloroquina/administração & dosagem , Ritmo Circadiano , Modelos Animais de Doenças , Injeções Intraperitoneais , Modelos Lineares , Masculino , Camundongos , Análise de Regressão
8.
Parasitol Today ; 7(12): 350-2, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15463414

RESUMO

Chronotherapy is the science of the timing of drug application so as to achieve optimal therapeutic success for the treatment of disease. Here, Irene Landau, Alain Chabaud, Gilles Cambie and Hagai Ginsburg show how a suitable animal model can be chosen, how the stage of parasite development most susceptible to the drug can be identified, and how this can eventually be used for the improvement of drug treatment.

9.
C R Acad Sci III ; 310(5): 183-8, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2107960

RESUMO

Freeze-thawing of blood infected with malaria parasites is a technique which brings about the destruction of all stages except the merozoites and makes possible investigations on the behaviour of these merozoites and the schizogonic rhythm of each species. Merozoites of Plasmodium y. yoelii remain in the blood during the 24 hrs. following inoculation; it is concluded that their penetration in the erythrocytes occurs gradually during this time. Synchronism is poor. Merozoites of P. vinckei petteri penetrate rapidly inside the erythrocytes independently of the time of inoculation. Infection is therefore synchronous and does not follow the circadian rhythm of the host. Penetration of merozoites of P. c. chabaudi is predominant at midnight when rodents are maintained with a normal circadian rhythm (light from 8 am to 8 pm) and predominant at noon when the rhythm of the host is inverted (light from 8 pm to 8 am). Infection is therefore synchronous and follows the host rhythm. The three species of plasmodia coexisting in Thamnomys rutilans from CAR show the same periodicity of 24 hrs. but, because of differences in the biology of the merozoites, they occupy three distinct niches. These notions have great practical implications in chronotherapy, as many data lead to the idea that merozoites are drug resistant.


Assuntos
Eritrócitos/parasitologia , Plasmodium/fisiologia , Roedores/parasitologia , África Central , Animais , Ritmo Circadiano , Plasmodium yoelii/fisiologia
10.
Ann Parasitol Hum Comp ; 66(1): 14-21, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1883151

RESUMO

The cyclic nature of malarial fever in conjunction with the pharmacokinetic characteristics of antimalarial drugs, call for the conception of a chrono-therapeutic approach for the treatment of the disease. An experimental murine malarial model was devised using the highly synchronous species Plasmodium vinckei petteri to test this rationale. Sub-curative doses of chloroquine were injected sub-cutaneously to mice either during the prepatent period or during patent infection. Inspection of the effect of drug applied at different stages of the parasitic cycle, revealed that medium size trophozoites (MT) were the most susceptible stage to chloroquine, while ring and young trophozoite stages were refractory to the drug. Chloroquine given during these latter stages, affected the parasites when they developed into the MT stage. Drug treatment during the MT stage phase-shifted the schizogonic cycle by 18 hours. Hence, treatment with two consecutive injections given 18 hours apart, i.e. timed to the overwhelming presence of the MT stage in the circulation, gave the best therapeutic results.


Assuntos
Cloroquina/uso terapêutico , Malária/tratamento farmacológico , Plasmodium/efeitos dos fármacos , Animais , Cloroquina/administração & dosagem , Modelos Animais de Doenças , Injeções Subcutâneas , Masculino , Camundongos , Periodicidade , Fatores de Tempo
11.
Lancet ; 345(8945): 289-91, 1995 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-7530793

RESUMO

To assess the risk of mother-to-infant transmission of hepatitis C virus (HCV), we followed up 116 babies of anti-HCV positive mothers, of whom 22 were coinfected with HIV and 94 had HCV alone. None of the babies whose mothers had HCV alone acquired HCV, while 8 babies (36%; p < 0.001) of mothers co-infected with HIV acquired HCV (5 babies) or HCV and HIV (3). There was no association between any specific maternal HCV genotype and enhanced risk of neonatal infection. HCV-RNA levels were significantly higher (p < 0.05) in mothers with HIV coinfection than in those with HCV alone. These data indicate that maternal HIV status correlates with enhanced level of viraemia which favours neonatal infection.


Assuntos
Infecções por HIV/complicações , Hepatite C/transmissão , Transmissão Vertical de Doenças Infecciosas , Adolescente , Adulto , Aleitamento Materno , Feminino , Seguimentos , Infecções por HIV/transmissão , Hepacivirus/imunologia , Anticorpos Anti-Hepatite/sangue , Hepatite C/sangue , Hepatite C/complicações , Anticorpos Anti-Hepatite C , Humanos , Recém-Nascido
12.
J Clin Lab Immunol ; 31(2): 55-7, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1983767

RESUMO

In an effort to improve the Walter Reed Staging System (WR), which mainly relies on immune depletion parameters, by introducing viral replication and T-cell activation markers, we examined by p24 antigenaemia and serum neopterin levels (SNL) 72 HIV positive PGL, ARC and AIDS patients (11 of whom classified as WR 2, 21 as WR 3, 16 as WR 5 and 24 as WR 6). While CD4 cell counts, already weakly correlating with the WR itself, did not significantly differ between p24 antigen (p24 AG) positive and negative patients, striking differences between the two groups, especially in PGL patients (p less than 0.0001), were found as far as SNL was concerned. In fact, SNL values, fluctuating around 10 and 30 nmol/l, respectively, in p24 Ag positive and negative patients regardless of their WR allocation, seemed rather to reflect, as global means of any given class, prevalence rate of p24 Ag positivity. We suggest, therefore, to use CD4/SNL ratio (R) for HIV infection and disease staging, as it not only may represent a compromise index between cellular immune depletion and T-cell activation, but also seems to take into account the viral replication component, already shown to be an important predictive marker of disease progression.


Assuntos
Biopterinas/análogos & derivados , Linfócitos T CD4-Positivos , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/sangue , Complexo Relacionado com a AIDS/sangue , Complexo Relacionado com a AIDS/microbiologia , Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/microbiologia , Adolescente , Adulto , Biopterinas/análise , Feminino , Infecções por HIV/microbiologia , Humanos , Contagem de Leucócitos , Masculino , Neopterina , Viremia/sangue
13.
Boll Ist Sieroter Milan ; 69(2): 423-30, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1983798

RESUMO

During a 12 month open clinical trial, 14 patients (6 with AIDS, 2 with ARC and 6 with PGL) were continuously administered a daily 1200 mg dose of Zidovudine. Clinical course was correlated with a number of serological (HIV p24 antigen, p17 and p24 antibodies) and immunological (CD4 cell counts, serum neopterin and beta 2-microglobulin levels) parameters. All patients survived until the end of the trial: none developed major opportunistic infections, but 5 required an average of 7 blood transfusions each. Disappearance of p24 Ag was observed in 4 out of 7 patients, although with a subsequent reappearance in 3; moreover, changes of p24 Ag and HIV core Ab profiles were generally paralleled by neopterin and, to a lesser extent, by CD4/neopterin ratio variations. In the long run, significant differences between baseline and end-point results were shown by neopterin, but not by CD4 cell counts and beta 2-microglobulin levels. Efficacy of Zidovudine therapy seemed to be mainly related to clinical, but even more so, to immunological and serological status at baseline; in fact, severe clinical deterioration was observed in 2 patients who had an already low CD4/neopterin ratio from the beginning, coupled with a p24 Ag positivity and a negativity of both anti-p17 and -p24. Conversely, a stable clinical condition was observed in those patients in whom the reverse was true.


Assuntos
Infecções por HIV/tratamento farmacológico , Zidovudina/uso terapêutico , Complexo Relacionado com a AIDS/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Biopterinas/análogos & derivados , Biopterinas/análise , Linfócitos T CD4-Positivos , Feminino , Anticorpos Anti-HIV/sangue , Proteína do Núcleo p24 do HIV/análise , Infecções por HIV/sangue , Infecções por HIV/imunologia , Humanos , Masculino , Neopterina , Resultado do Tratamento , Microglobulina beta-2/análise
14.
J Clin Microbiol ; 32(2): 403-6, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8150950

RESUMO

A new anti-human immunodeficiency virus type 1 and 2 (anti-HIV 1 and 2) test is described. It uses recombinant p24 and peptides covering gp32, gp41, and gp120 to identify HIV-1 and HIV-2 infections. This test has been shown to be specific (99.5%) and sensitive (99.8%). In this respect, the assay was equal or superior to anti-HIV 1 and 2 tests run as references. The test was able to discriminate sera from patients with HIV infections from those from uninfected individuals with excellence; it also exerted high intra- and interassay precisions. The "modular" concept of the test allows the use of single components (gp32 or gp41) to separate between HIV-2 and HIV-1 infections, respectively.


Assuntos
Infecções por HIV/diagnóstico , HIV-1 , HIV-2 , Técnicas Imunoenzimáticas , Diagnóstico Diferencial , Estudos de Avaliação como Assunto , Feminino , Anticorpos Anti-HIV/sangue , Antígenos HIV , Infecções por HIV/imunologia , Soropositividade para HIV/diagnóstico , Soropositividade para HIV/imunologia , HIV-1/imunologia , HIV-2/imunologia , Humanos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Masculino , Gravidez , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
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