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1.
Sensors (Basel) ; 21(23)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34884145

RESUMO

The automated quantification of the behaviour of freely moving animals is increasingly needed in applied ethology. State-of-the-art approaches often require tags to identify animals, high computational power for data collection and processing, and are sensitive to environmental conditions, which limits their large-scale utilization, for instance in genetic selection programs of animal breeding. Here we introduce a new automated tracking system based on millimetre-wave radars for real time robust and high precision monitoring of untagged animals. In contrast to conventional video tracking systems, radar tracking requires low processing power, is independent on light variations and has more accurate estimations of animal positions due to a lower misdetection rate. To validate our approach, we monitored the movements of 58 sheep in a standard indoor behavioural test used for assessing social motivation. We derived new estimators from the radar data that can be used to improve the behavioural phenotyping of the sheep. We then showed how radars can be used for movement tracking at larger spatial scales, in the field, by adjusting operating frequency and radiated electromagnetic power. Millimetre-wave radars thus hold considerable promises precision farming through high-throughput recording of the behaviour of untagged animals in different types of environments.


Assuntos
Movimento , Radar , Agricultura , Animais , Coleta de Dados , Monitorização Fisiológica , Ovinos
2.
Sensors (Basel) ; 19(15)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362437

RESUMO

This paper addresses the implementation of autonomous radiofrequency identification sensor nodes based on wireless power transfer. For size reduction, a switching method is proposed in order to use the same frequency band for both supplying power to the nodes and wirelessly transmitting the nodes' data. A rectenna harvests the electromagnetic energy delivered by the dedicated radiofrequency source for charging a few-mF supercapacitor. For supercapacitors of 7 mF, it is shown that the proposed autonomous sensor nodes were able to wirelessly communicate with the reader at 868 MHz for 10 min without interruption for a tag-to-reader separation distance of 1 meter. This result was obtained from effective radiated powers of 2 W during the supercapacitor charging and of 100 mW during the wireless data communication.

3.
Sensors (Basel) ; 19(6)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871142

RESUMO

This paper reports the indoor wireless measurement of pressure from zero-power (or passive) microwave (24 GHz) sensors. The sensors are packaged and allow the remote measurement of overpressure up to 2.1 bars. Their design, fabrication process and packaging are detailed. From the measurement of sensor scattering parameters, the outstanding sensitivity of 995 MHz/bar between 0.8 and 2.1 bars was achieved with the full-scale measurement range of 1.33 GHz. Moreover, the 3D radar imagery technique was applied for the remote interrogation of these sensors in electromagnetic reverberant environments. The full-scale dynamic range of 4.9 dB and the sensitivity of 4.9 dB/bar between 0.7 and 1.7 bars were achieved with radar detection in a highly reflective environment. These measurement results demonstrate for the first time the ability of the radar imagery technique to interrogate fully passive pressure sensors in electromagnetic reverberant environments.

4.
Haematologica ; 94(3): 335-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19176363

RESUMO

BACKGROUND: Elevated serum ferritin levels are frequently encountered in clinical situations and once iron overload or inflammation has been ruled out, many cases remain unexplained. Genetic causes of hyperferritinemia associated to early cataract include mutations in the iron responsive element in the 5' untranslated region of the L ferritin mRNA, responsible for the hereditary hyperferritinemia cataract syndrome. DESIGN AND METHODS: We studied 91 probands with hyperferritinemia comprising 25 family cases belonging to families with at least two cases of unexplained hyperferritinemia, and 66 isolated cases. In the families, we also analyzed 30 relatives. Hyperferritinemia was considered as unexplained when transferrin saturation was below 45% and/or serum iron below 25 mumol/L and/or no tissue iron excess was detected, when inflammation had been ruled out and when iron responsive element mutation was absent. We carried out sequencing analysis of the FTL gene coding the L ferritin. RESULTS: A novel heterozygous p.Thr30Ile mutation in the NH2 terminus of L ferritin subunit was identified in 17 probands out of the cohort. The mutation was shown to cosegregate with hyperferritinemia in all the 10 families studied. No obvious clinical symptom was found associated with the presence of the mutation. This unique mutation is associated with an unusually high percentage of ferritin glycosylation. CONCLUSIONS: This missense mutation of FTL represents a new cause of genetic hyperferritinemia without iron overload. We hypothesized that the mutation increases the efficacy of L ferritin secretion by increasing the hydrophobicity of the N terminal "A" alpha helix.


Assuntos
Ferritinas/sangue , Sobrecarga de Ferro/sangue , Mutação de Sentido Incorreto , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Apoferritinas , Criança , Saúde da Família , Feminino , Ferritinas/química , Ferritinas/genética , Ferritinas/metabolismo , Glicosilação , Heterozigoto , Humanos , Sobrecarga de Ferro/genética , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Estrutura Secundária de Proteína , Adulto Jovem
5.
Clin Chim Acta ; 470: 70-74, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28457853

RESUMO

Congenital disorders of glycosylation (CDGs) are rare inherited disorders affecting glycosylation of proteins and lipids and sharing very heterogeneous multivisceral symptoms. The biochemical screening of these diseases is currently limited to electrophoresis or HPLC separation/quantification of serum transferrin glycoforms and is relatively frequently hampered by genetic polymorphism. Further, it has been shown that transferrin glycosylation can be very poorly affected in confirmed CDGs. We developed a fast and simple two-dimensional (2-DE) Western-blot analysis applied to the simultaneous detection of various serum glycoproteins, i.e. haptoglobin, α1-anti-trypsin, transferrin and α1-acid glycoprotein, and applied it to a large cohort of CDGs and secondary glycosylation disorders. When separated using 2-DE, haptoglobin ß glycoforms showed clear abnormalities in all interpretable CDG type I and CDG type II patterns. Although secondary glycosylation defects such as alcoholism, untreated fructosemia and bacterial neuraminidase remain to be excluded, we showed that 2-DE pattern of haptoglobin ß glycoforms thus constitute a very reliable additional biomarker of all types of CDGs. Coupled with common screening techniques and glycans mass spectrometry, it can orientate and facilitate the way towards CDG molecular diagnostic.


Assuntos
Defeitos Congênitos da Glicosilação/metabolismo , Eletroforese em Gel Bidimensional , Haptoglobinas/metabolismo , Biomarcadores/metabolismo , Glicosilação , Haptoglobinas/isolamento & purificação , Humanos , Transferrina/metabolismo
6.
Eur J Pediatr ; 166(2): 153-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17089090

RESUMO

Chronic granulomatous disease (CGD) is a rare primary immunodeficiency caused by mutations of one of the subunits of phagocyte reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase leading to decreased or complete absence of neutrophil oxidative burst. We report the clinical and laboratory findings in two young unrelated females 14 and 9 years of age and natives of Tahiti and Reunion Islands, respectively, with severe X-linked granulomatous disease. In both cases, the infectious pattern was unusual, with convergent symptoms suggesting underlying mycobacterial infection. Functional analysis revealed low residual NADPH oxidase activity with about 5-10% of normal neutrophil population. De novo null mutations affecting the CYBB gene that encodes the gp91 protein were found in both cases in the heterozygous state (in patient 1, p.Arg130X in exon 5, and in patient 2, a novel insertion in exon 6, c.632_633insCATC). Methylation analysis confirmed that phenotype expression was linked to skewed X inactivation and showed that the de novo mutation arose on the maternally inherited chromosome in one case and on the paternally inherited chromosome in the other case. In conclusion, X-linked CGD carriers could therefore be at risk for severe infectious diseases depending on the skewed X inactivation pattern and the infectious context.


Assuntos
DNA/genética , Família , Predisposição Genética para Doença , Doença Granulomatosa Crônica/genética , Glicoproteínas de Membrana/genética , Mutação , NADPH Oxidases/genética , Adolescente , Western Blotting , Criança , Feminino , Doença Granulomatosa Crônica/sangue , Humanos , NADPH Oxidase 2 , NADPH Oxidases/sangue , Neutrófilos/enzimologia , Estresse Oxidativo/genética , Reação em Cadeia da Polimerase , Índice de Gravidade de Doença
7.
J Immunol ; 179(7): 4754-65, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17878374

RESUMO

Polymorphonuclear neutrophils (PMN) play a key role in innate immunity. Their activation and survival are tightly regulated by microbial products via pattern recognition receptors such as TLRs, which mediate recruitment of the IL-1R-associated kinase (IRAK) complex. We describe a new inherited IRAK-4 deficiency in a child with recurrent pyogenic bacterial infections. Analysis of the IRAK4 gene showed compound heterozygosity with two mutations: a missense mutation in the death domain of the protein (pArg12Cys) associated in cis-with a predicted benign variant (pArg391His); and a splice site mutation in intron 7 that led to the skipping of exon 7. A nontruncated IRAK-4 protein was detected by Western blotting. The patient's functional deficiency of IRAK-4 protein was confirmed by the absence of IRAK-1 phosphorylation after stimulation with all TLR agonists tested. The patient's PMNs showed strongly impaired responses (L-selectin and CD11b expression, oxidative burst, cytokine production, cell survival) to TLR agonists which engage TLR1/2, TLR2/6, TLR4, and TLR7/8; in contrast, the patient's PMN responses to CpG-DNA (TLR9) were normal, except for cytokine production. The surprisingly normal effect of CpG-DNA on PMN functions and apoptosis disappeared after pretreatment with PI3K inhibitors. Together, these results suggest the existence of an IRAK-4-independent TLR9-induced transduction pathway leading to PI3K activation. This alternative pathway may play a key role in PMN control of infections by microorganisms other than pyogenic bacteria in inherited IRAK-4 deficiency.


Assuntos
Quinases Associadas a Receptores de Interleucina-1/deficiência , Neutrófilos/imunologia , Neutrófilos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Receptor Toll-Like 9/metabolismo , Adolescente , Sequência de Bases , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Interleucina-1/farmacologia , Quinases Associadas a Receptores de Interleucina-1/química , Quinases Associadas a Receptores de Interleucina-1/genética , Interleucina-18/farmacologia , Masculino , Modelos Moleculares , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Mutação/genética , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Estrutura Terciária de Proteína , Espécies Reativas de Oxigênio/metabolismo , Receptor Toll-Like 9/agonistas
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