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1.
Comput Ind Eng ; 168: 108125, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35370350

RESUMO

The pandemic by COVID-19 is causing a devastating effect on the health of the global population. Currently, there are several efforts to prevent the spread of the virus. Among those efforts, cleaning and disinfecting public areas have become important tasks and they should be automated in future smart cities. To contribute in this direction, this paper proposes a coverage path planning method for a spraying drone, an unmanned aerial vehicle that has mounted a sprayer/sprinkler system, that can disinfect areas. State-of-the-art planners consider a camera instead of a sprinkler, in consequence, the expected coverage will differ in running time because the liquid dispersion is different from a camera's projection model. In addition, current planners assume that the vehicles can fly outside the target region; this assumption can not be satisfied in our problem, because disinfections are performed at low altitudes. Our method presents i) a new sprayer/sprinkler model that fits a more realistic coverage volume to the drop dispersion and ii) a planning method that efficiently restricts the flight to the region of interest avoiding potential collisions in bounded scenes. The algorithm has been tested in several simulation scenes, showing that it is effective and covers more areas with respect to two approaches in the literature. Note that the proposal is not limited to disinfection applications, but can be applied to other ones, such as painting or precision agriculture.

2.
Clin Radiol ; 77(3): e208-e214, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34887070

RESUMO

AIM: To compare the machine learning computed tomography (CT) quantification tool, Computer-Aided Lung Informatics for Pathology Evaluation and Ratings (CALIPER) to pulmonary function testing (PFT) in assessing idiopathic pulmonary fibrosis (IPF) for patients undergoing treatment and determine the effects of limited (LD) and ultra-low dose (ULD) CT on CALIPER performance. MATERIALS AND METHODS: Thirty-eight IPF patients underwent PFT and standard, LD, and ULD CT. CALIPER classified each CT voxel into either vessel-related structures (VRS), normal, reticular (R), honeycomb (HC) or ground-glass (GG) features. CALIPER-derived interstitial lung disease (ILD) extent represented the sum of GG, R and HC values. Repeated-measures correlation coefficient (ρrm) and 95% confidence interval (CI) evaluated CALIPER features correlation with PFT. Lin's concordance correlation coefficient (CCC) assessed concordance of CALIPER parameters across different CT dosages. RESULTS: Twenty patients completed 12 months of follow-up. CALIPER ILD correlated significantly with percent predicted (%) forced vital capacity (FVC) and forced expiratory volume in 1 second (%FEV1; p=0.004, ρrm -0.343, 95% CI [-0.547, -0.108] and 0.008, -0.321, [-0.518, -0.07], respectively). VRS significantly correlated with %FVC and %FEV1 (p=0.000, ρrm -0.491, 95% CI [-0.685, -0.251] and -0.478, 0.000, [-0.653, -0.231], respectively). There was near perfect LD and moderate ULD concordance with standard dose CT for both ILD (CCC 0.995, 95% CI 0.988-0.999 and 0.9, 0.795-0.983, respectively) and VRS (CCC 0.989, 95% CI 0.963-0.997 and 0.915, 0.806-0.956, respectively). CONCLUSIONS: CALIPER parameters correlate well with PFTs for evaluation of IPF in patients undergoing anti-fibrotic treatment without being influenced by dose variation. CALIPER may serve as a robust, objective adjunct to PFTs in assessing anti-fibrotic treatment related changes.


Assuntos
Fibrose Pulmonar Idiopática/diagnóstico por imagem , Fibrose Pulmonar Idiopática/radioterapia , Aprendizado de Máquina , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Capacidade Vital
3.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1989-1992, Sept.-Oct. 2020.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131572

RESUMO

The morphological characteristics of the autologous platelet concentrate (APC) of 31 dogs were evaluated after cooling and freezing in 6% DMSO. Blood from the jugular vein of each patient was collected and centrifuged at 191g for six minutes to obtain APC. In the fresh sample, the platelet count, MPV, PDW and cell morphology were evaluated. Four samples of each animal were sent for storage, one refrigerated at 4°C for seven days, another for 30 days and two more stored in a freezer at -80°C in the same time interval, using 6% DMSO as cryoprotectant. The conserved samples were submitted to the same laboratory analysis as the fresh sample. There was a difference between fresh and preserved samples for platelet count, cell concentration, MPV and PDW (P<0.05), except in the 30-day refrigerated group, which showed severe morphological changes. In the frozen group for seven days, no difference was observed in the percentage of activation (P>0.05). The results obtained lead to the conclusion that cryopreservation with 6% DMSO at -80°C for seven days is a favorable option for the maintenance of platelet concentrations and the morphological characteristics of APC in dogs.(AU)


Assuntos
Animais , Cães , Refrigeração , Criopreservação , Plasma Rico em Plaquetas/citologia , Dimetil Sulfóxido
4.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 107-114, Jan.-Feb. 2020. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1088916

RESUMO

O objetivo deste trabalho foi mensurar as dimensões da patela de cadáveres caninos e avaliar sua relação com a massa corporal. Para a realização das medidas patelares, foram utilizados 70 cadáveres de cães adultos, com massa corpórea de 1 a 50kg, sem evidência clínica de afecção na articulação femorotibiopatelar. Com auxílio de um paquímetro, foram mensurados os comprimentos externo e interno, a largura externa no terço médio, a largura e a espessura internas nos terços proximal, médio e distal das patelas. Também foram mensuradas a largura nos terços proximal, médio e distal, a profundidade nos terços proximal, médio e distal do sulco troclear; essas medidas foram exclusivamente internas. Observou-se, de forma geral, forte correlação entre as medidas patelares e a massa corporal de cadáveres de cães. Nas condições deste estudo, pode-se concluir que o tamanho da patela varia segundo a massa corporal do cão e que essas medidas devem ser consideradas ao se planejar uma substituição protética.(AU)


The aim of this study was to measure the canine cadaver patellar dimensions and evaluate its relationship with body mass. 70 cadavers of adult dogs were used, with a body mass between 1 and 50kg, without clinical evidence of affection in the stifle joint. The external and internal lengths, external width in the middle third, width and thickness of the proximal, middle and distal thirds were measured using a pachymeter. The width was also measured in the proximal third, middle third and distal third, depth in the proximal third, middle third and distal third of the trochlear groove; these measurements were exclusively internal. A strong correlation was observed between the patellar dimension and body mass of canine cadavers. Under this study conditions, it is possible to conclude that the patellar size varies according to the canine body mass and these measures should be considered when planning a prosthetic replacement.(AU)


Assuntos
Animais , Cães , Patela/anatomia & histologia , Próteses e Implantes/veterinária , Peso Corporal , Luxação Patelar/veterinária , Cadáver
5.
Lab Chip ; 16(2): 312-25, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26659477

RESUMO

In cancer research and personalized medicine, new tissue culture models are needed to better predict the response of patients to therapies. With a concern for the small volume of tissue typically obtained through a biopsy, we describe a method to reproducibly section live tumor tissue to submillimeter sizes. These micro-dissected tissues (MDTs) share with spheroids the advantages of being easily manipulated on-chip and kept alive for periods extending over one week, while being biologically relevant for numerous assays. At dimensions below ~420 µm in diameter, as suggested by a simple metabolite transport model and confirmed experimentally, continuous perfusion is not required to keep samples alive, considerably simplifying the technical challenges. For the long-term culture of MDTs, we describe a simple microfluidic platform that can reliably trap samples in a low shear stress environment. We report the analysis of MDT viability for eight different types of tissues (four mouse xenografts derived from human cancer cell lines, three from ovarian and prostate cancer patients, and one from a patient with benign prostatic hyperplasia) analyzed by both confocal microscopy and flow cytometry over an 8-day incubation period. Finally, we provide a proof of principle for chemosensitivity testing of human tissue from a cancer patient performed using the described MDT chip method. This technology has the potential to improve treatment success rates by identifying potential responders earlier during the course of treatment and providing opportunities for direct drug testing on patient tissues in early drug development stages.


Assuntos
Antineoplásicos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Dispositivos Lab-On-A-Chip , Microdissecção , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Medicina de Precisão , Técnicas de Cultura de Tecidos/instrumentação , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Citometria de Fluxo , Humanos , Camundongos , Microscopia Confocal
6.
Environ Entomol ; 44(5): 1287-98, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26314006

RESUMO

Hunting ants are predators of organisms belonging to different trophic levels. Their presence, abundance, and diversity may reflect the diversity of other ants and contribute to evaluate habitat conditions. Between 2003 and 2005 the restoration of seven corridors in an Andean rural landscape of Colombia was performed. The restoration took place in lands that were formerly either forestry plantations or pasturelands. To evaluate restoration progress, hunting ants were intensely sampled for 7 yr, using sifted leaf litter and mini-Winkler, and pitfall traps in 21 plots classified into five vegetation types: forests, riparian forests, two types of restored corridors, and pasturelands. The ant communities were faithful to their habitat over time, and the main differences in ant composition, abundance, and richness were due to differences among land use types. The forests and riparian forests support 45% of the species in the landscape while the restored corridors contain between 8.3-25%. The change from forest to pasturelands represents a loss of 80% of the species. Ant composition in restored corridors was significantly different than in forests but restored corridors of soil of forestry plantations retained 16.7% more species than restored corridors from pasturelands. Ubiquitous hunting ants, Hypoponera opacior (Forel) and Gnamptogenys ca andina were usually associated with pastures and dominate restored corridors. Other cryptic, small, and specialized hunting ants are not present in the restored corridors. Results suggest that the history of land use is important for the biodiversity of hunting ants but also that corridors have not yet effectively contributed toward conservation goals.


Assuntos
Formigas/fisiologia , Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Animais , Colômbia , Florestas , Comportamento Predatório
8.
Science ; 346(6213): 1080-4, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25378461

RESUMO

Supermassive black holes with masses of millions to billions of solar masses are commonly found in the centers of galaxies. Astronomers seek to image jet formation using radio interferometry but still suffer from insufficient angular resolution. An alternative method to resolve small structures is to measure the time variability of their emission. Here we report on gamma-ray observations of the radio galaxy IC 310 obtained with the MAGIC (Major Atmospheric Gamma-ray Imaging Cherenkov) telescopes, revealing variability with doubling time scales faster than 4.8 min. Causality constrains the size of the emission region to be smaller than 20% of the gravitational radius of its central black hole. We suggest that the emission is associated with pulsar-like particle acceleration by the electric field across a magnetospheric gap at the base of the radio jet.

9.
Biomed Res Int ; 2014: 529519, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24783210

RESUMO

This paper presents different applications, in various foodstuffs, by a novel electronic nose (EN) based on a mixed metal oxide sensors array composed of thin films as well as nanowires. The electronic nose used for this work has been done, starting from the commercial model EOS835 produced by SACMI Scarl. The SENSOR Lab (CNR-INO, Brescia) has produced both typologies of sensors, classical MOX and the new technologies with nanowire. The aim of this work was to test and to illustrate the broad spectrum of potential uses of the EN technique in food quality control and microbial contamination diagnosis. The EN technique was coupled with classical microbiological and chemical techniques, like gas chromatography with mass spectroscopy (GC-MS) with SPME technique. Three different scenarios are presented: (a) detection of indigenous mould in green coffee beans, (b) selection of microbiological spoilage of Lactic Acid Bacteria (LAB), and (c) monitoring of potable water. In each case, the novel EN was able to identify the spoiled product by means of the alterations in the pattern of volatile organic compounds (VOCs), reconstructed by principal component analysis (PCA) of the sensor responses. The achieved results strongly encourage the use of EN in industrial laboratories. Finally, recent trends and future directions are illustrated.


Assuntos
Nariz Eletrônico , Análise de Alimentos , Microbiologia de Alimentos , Membranas Artificiais , Nanofios/química , Compostos Orgânicos Voláteis/análise , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Microbiologia de Alimentos/instrumentação , Microbiologia de Alimentos/métodos
12.
DNA Res ; 20(6): 567-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23857904

RESUMO

We present the sequencing and annotation of the Leishmania (Leishmania) amazonensis genome, an etiological agent of human cutaneous leishmaniasis in the Amazon region of Brazil. L. (L.) amazonensis shares features with Leishmania (L.) mexicana but also exhibits unique characteristics regarding geographical distribution and clinical manifestations of cutaneous lesions (e.g. borderline disseminated cutaneous leishmaniasis). Predicted genes were scored for orthologous gene families and conserved domains in comparison with other human pathogenic Leishmania spp. Carboxypeptidase, aminotransferase, and 3'-nucleotidase genes and ATPase, thioredoxin, and chaperone-related domains were represented more abundantly in L. (L.) amazonensis and L. (L.) mexicana species. Phylogenetic analysis revealed that these two species share groups of amastin surface proteins unique to the genus that could be related to specific features of disease outcomes and host cell interactions. Additionally, we describe a hypothetical hybrid interactome of potentially secreted L. (L.) amazonensis proteins and host proteins under the assumption that parasite factors mimic their mammalian counterparts. The model predicts an interaction between an L. (L.) amazonensis heat-shock protein and mammalian Toll-like receptor 9, which is implicated in important immune responses such as cytokine and nitric oxide production. The analysis presented here represents valuable information for future studies of leishmaniasis pathogenicity and treatment.


Assuntos
Genoma de Protozoário , Leishmania/genética , Interações Hospedeiro-Parasita , Humanos , Leishmania/metabolismo , Leishmaniose Cutânea/parasitologia , Modelos Genéticos , Anotação de Sequência Molecular , Dados de Sequência Molecular , Filogenia
13.
Colloids Surf B Biointerfaces ; 101: 370-5, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23010043

RESUMO

Biomagnetic immobilization of histidine-rich proteins based on the single-step affinity adsorption of transition metal ions continues to be a suitable practice as a cost effective and a up scaled alternative to the to multiple-step chromatographic separations. In our previous work, we synthesised Porous Magnetic silica (PMS) spheres by one-step hydrothermal-assisted modified-stöber method. The obtained spheres were decorated with Ni(2+) and Co(2+), and evaluated for the capture of a H6-Tagged green fluorescence protein (GFP-H6) protein. The binding capacity of the obtained spheres was found to be slightly higher in the case Ni(2+) decorated PMS spheres (PMSNi). However, comparing with commercial products, the binding capacity was found to be lower than the expected. In this way, the present work is an attempt to improve the binding capacity of PMSNi to histidine-rich proteins. We find that increasing the amount of Ni(2+) onto the surface of the PMS spheres leads to an increment of the binding capacity to GFP-H6 by a factor of two. On the other hand, we explore how the size of histidine-rich protein can affect the binding capacity comparing the results of the GFP-6H to those of the His-tagged α-galactosidase (α-GLA). Finally, we demonstrate that the optimization of the magnetophoresis parameters during washing and eluting steps can lead to an additional improvement of the binding capacity.


Assuntos
Histidina/isolamento & purificação , Níquel/química , Proteínas/isolamento & purificação , Dióxido de Silício/química , Cetrimônio , Compostos de Cetrimônio , Cobalto/química , Proteínas de Fluorescência Verde , Magnetismo , Microscopia Eletrônica de Transmissão , Porosidade , Suspensões , alfa-Galactosidase/química
14.
Antimicrob Agents Chemother ; 57(1): 382-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23114761

RESUMO

Rhodotorula species are emergent fungal pathogens capable of causing invasive infections, primarily fungemia. They are particularly problematic in immunosuppressed patients when using a central venous catheter. In this study, we evaluated the species distribution of 51 clinical and 8 environmental Rhodotorula species isolates using the ID32C system and internal transcribed spacer (ITS) sequencing. Antifungal susceptibility testing and biofilm formation capability using a crystal violet staining assay were performed. Using ITS sequencing as the gold standard, the clinical isolates were identified as follows: 44 R. mucilaginosa isolates, 2 R. glutinis isolates, 2 R. minuta isolates, 2 R. dairenensis isolates, and 1 Rhodosporidium fluviale isolate. The environmental isolates included 7 R. mucilaginosa isolates and 1 R. slooffiae isolate. Using the ID32C system, along with a nitrate assimilation test, only 90.3% of the isolates tested were correctly identified. In the biofilm formation assay, R. mucilaginosa and R. minuta exhibited greater biofilm formation ability compared to the other Rhodotorula species; the clinical isolates of R. mucilaginosa showed greater biofilm formation compared to the environmental isolates (P = 0.04). Amphotericin B showed good in vitro activity (MIC ≤ 1 µg/ml) against planktonic cells, whereas voriconazole and posaconazole showed poor activity (MIC(50)/MIC(90), 2/4 µg/ml). Caspofungin and fluconazole MICs were consistently high for all isolates tested (≥64 µg/ml and ≥ 4 µg/ml, respectively). In this study, we emphasized the importance of molecular methods to correctly identify Rhodotorula species isolates and non-R. mucilaginosa species in particular. The antifungal susceptibility profile reinforces amphotericin B as the antifungal drug of choice for the treatment of Rhodotorula infections. To our knowledge, this is the first study evaluating putative differences in the ability of biofilm formation among different Rhodotorula species.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , DNA Espaçador Ribossômico/genética , Fungemia/microbiologia , Rhodotorula/efeitos dos fármacos , Rhodotorula/genética , Microbiologia do Solo , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , DNA Espaçador Ribossômico/classificação , Fungemia/tratamento farmacológico , Violeta Genciana , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Filogenia , Plâncton/efeitos dos fármacos , Plâncton/crescimento & desenvolvimento , Rhodotorula/classificação , Rhodotorula/isolamento & purificação , Análise de Sequência de DNA , Especificidade da Espécie
15.
J Colloid Interface Sci ; 365(1): 156-62, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21996010

RESUMO

The complete elimination of enzymes from the reaction mixture and the possibility of its recycling for several rounds result in great benefits, allowing the reduction of the enzyme consumption and their usability in continuous processes. In this work, it is evaluated the capture of a H6-tagged green fluorescence protein (GFP-H6) on porous magnetic spheres using the Co(2+) and Ni(2+) affinity adsorption as a possible cost-effective and up-scaled alternative way for the immobilization of His-tagged proteins. For this purpose, Porous Magnetic Silica (PMS) spheres were synthesized by one-step hydrothermal-assisted modified-Stöber method. The obtained spheres have a homogenous size distribution of 400 nm diameter. The γ-Fe(2)O(3) nanoparticles are homogenously distributed in the silica matrix. The obtained PMS spheres have a saturation magnetization of about 10 emu/g. Magnetophoresis measurements show a total separation time of 16 min at 60 T/m. The obtained PMS spheres were successfully and homogenously decorated with Co(2+) and Ni(2+) and then evaluated for the capture of a GFP-H6 protein. The results were compared with the performance of the commercial beads Dynabeads® His-Tag Isolation & Pulldown.


Assuntos
Cobalto/química , Proteínas de Fluorescência Verde/isolamento & purificação , Histidina/isolamento & purificação , Nanopartículas de Magnetita/química , Níquel/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Dióxido de Silício/química , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Histidina/química , Histidina/genética , Porosidade , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética
17.
Eur J Endocrinol ; 164(4): 457-65, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21270112

RESUMO

BACKGROUND: Pituitary stalk interruption syndrome (PSIS) is a particular entity in the population of patients with hypopituitarism. Only rare cases have a known genetic cause. OBJECTIVES: i) To compare subgroups with or without extra-pituitary malformations (EPM) in a cohort of PSIS patients to identify predictive factors of evolution, ii) to determine the incidence of mutations of the known pituitary transcription factor genes in PSIS. Study design We analyzed features of 83 PSIS patients from 80 pedigrees and screened HESX1, LHX4, OTX2, and SOX3 genes. RESULTS: PSIS had a male predominance and was rarely familial (5%). Pituitary hypoplasia was observed only in the group with EPM. Multiple hormone deficits were observed significantly more often with versus without EPM (87.5 vs 69.5% respectively). Posterior pituitary location along the stalk was a significant protective factor regarding severity of hormonal phenotype. A novel HESX1 causative mutation was found in a consanguineous family, and two LHX4 mutations were present in familial PSIS. CONCLUSION: PSIS patients with EPM had a more severe hormonal disorder and pituitary imaging status, suggesting an antenatal origin. HESX1 or LHX4 mutations accounted for <5% of cases and were found in consanguineous or familial cases.


Assuntos
Proteínas de Homeodomínio/genética , Hipófise/anormalidades , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Proteínas com Homeodomínio LIM , Imageamento por Ressonância Magnética , Masculino , Mutação , Fatores de Transcrição Otx/genética , Hipófise/patologia , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição/genética
18.
Neurology ; 76(2): 172-8, 2011 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-21220721

RESUMO

OBJECTIVE: We studied a case series of peripheral nerve hyperexcitability (PNH) aiming to describe clinical characteristics, immunologic and cancer associations, antibodies against neuronal antigens (voltage-gated potassium channel antibodies [VGKC-Abs] and other), and muscle biopsy findings. METHODS: Patients presenting with clinical and electrophysiologic signs of PNH were selected. We studied clinical and electrophysiologic features; a panel of non-neuronal organ-specific antibodies, immunofluorescence on rat nervous tissues, and radioimmunoprecipitation for VGKC-Abs; and muscle biopsies. RESULTS: Thirty-eight patients were included. After the exclusion of 6 cases with axonopathy of known origin, patients were subdivided according to the presence of electrophysiologic findings of motor axonopathy and association with cancer: axonopathic-PNH (group A: 12 patients), isolated nonparaneoplastic PNH (group B: 16 patients), and isolated paraneoplastic PNH (3 with thymoma and myasthenia gravis, 1 with thyroid carcinoma). PNH clinical features were similar in groups A and B. We found an overall high prevalence of clinical autoimmunity (33% of group A and 63% of group B) and systemic non-neuronal autoantibodies (42% of group A and 75% of group B). However, VGKC-Abs were only positive in 2 patients of group B. Ten patients underwent muscle biopsy, which showed inflammatory changes in 2 cases and nonspecific myopathic features in 8. CONCLUSIONS: PNH is a heterogeneous disorder involving the peripheral nerves in patients with a high propensity for developing autoimmunity. Associated muscle diseases are frequent in the form of myositis, myasthenia gravis, or nonspecific myopathic pathologic findings. VGKC-Abs were uncommon in this series.


Assuntos
Anticorpos Antinucleares/metabolismo , Músculo Esquelético/patologia , Doenças do Sistema Nervoso Periférico/imunologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Adolescente , Adulto , Idoso , Biópsia , Eletrofisiologia , Feminino , Imunofluorescência , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/imunologia , Polineuropatia Paraneoplásica/imunologia , Polineuropatia Paraneoplásica/fisiopatologia , Doenças do Sistema Nervoso Periférico/patologia , Ensaio de Radioimunoprecipitação , Fatores de Risco , Timoma/imunologia , Neoplasias da Glândula Tireoide/imunologia , Adulto Jovem
19.
Clin Endocrinol (Oxf) ; 74(1): 21-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21039729

RESUMO

AIMS AND METHODS: The aim of this prospective study was to compare the diagnostic value of [¹8F]FDOPA-PET and [¹¹¹In]pentetreotide-SPECT somatostatin receptor scintigraphy (SRS) in patients with nonmetastatic extra-adrenal paragangliomas (PGLs). Twenty-five consecutive unrelated patients who were known or suspected of having nonmetastatic extra-adrenal PGLs were prospectively evaluated with SRS and [¹8F]FDOPA-PET. ¹³¹I-MIBG and [¹8F]FDG-PET were added to the work-up in patients with a personal or familial history of PGL, predisposing mutations, abdominal PGLs, metanephrine hypersecretion and abdominal foci on SRS and/or [¹8F]FDOPA-PET. RESULTS: SRS correctly detected 23/45 lesions of which 20 were head or neck lesions (H&N) and 3 were abdominal lesions. [¹8F]FDOPA-PET detected significantly more lesions than SRS (39/45, P < 0·001). Both SRS and ¹8F-DOPA-PET detected significantly more H&N than abdominal lesions (66·7% vs 20%, P = 0·003 and 96·7% vs 67%, P = 0·012, respectively). In two patients with the succinate dehydrogenase D (SDHD) mutation, [¹8F]FDOPA-PET missed five abdominal PGLs which were detected by the combination of SRS, [¹³¹I]MIBG and [¹8F]FDG-PET. A lesion-based analysis using a forward stepwise logistic regression model demonstrates that size ≤ 10 mm (P = 0·002) and abdominal lesions (P = 0·031) were independently associated with "[¹8F]FDOPA-PET diagnosis only". In turn, a previous history of surgery and/or the presence of germline mutation was associated with lower lesion size (P = 0·001). CONCLUSIONS: The sensitivity of SRS for localizing parasympathetic PGLs is lower than originally reported, and [¹8F]FDOPA-PET is better than SRS for localizing small lesions. SRS should be replaced by [¹8F]FDOPA-PET as the first-line imaging procedure in H&N PGL, especially in patients at risk of multifocal disease (predisposing mutations and or previous history of surgery).


Assuntos
Paraganglioma Extrassuprarrenal/diagnóstico , Tomografia por Emissão de Pósitrons , Somatostatina/análogos & derivados , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paraganglioma Extrassuprarrenal/metabolismo , Estudos Prospectivos , Receptores de Somatostatina/metabolismo , Adulto Jovem
20.
Rev. ciênc. farm. básica apl ; 31(3)set.-dez. 2010.
Artigo em Inglês | LILACS | ID: lil-570160

RESUMO

Este estudo demonstra como a Beta-galactosidase pode ser desativada e reativada usando EDTA e íons metálicos divalentes. A enzima foi desativada após 20 minutos na presença de EDTA. Desativação máxima para a menor concentração de EDTA (10-3 mol.L-1) ocorreu na presença do tampão Tris-HCl. A enzima recuperou 50% de sua atividade inicial após 10 minutos na presença de Mg2+ em concentrações superiores a 0,1mmol.L-1.Concentrações de 10-4 e 10-3 mol.L-1 de Mn2+ e Co2+ foram suficientes para reativar a enzima em 300% comparado ao controle de íons Mn2+ e aproximadamente 100% para íons Co2+. A enzima perdeu gradualmente a sua atividade quando a concentração foi de 10-2 mol.L-1. Ni2+ e Zn2+ foram incapazes de restabelecer a atividade catalítica. Km app e Vmax app foram 1,95 ± 0,05 mmol.L-1 e 5,40 ± 0,86 x 10-2 mmol.min-1.mg-1. A temperatura e pH ótimos foram 34ºC e 7,5. A meia vida da holoenzima foi de 17,5 min a 30ºC e para a apoenzima foi de 11,0 min a 30ºC. Quanto à variação de pH, a apoenzima provou ser mais sensível que a holoenzima.


In this study, it was demonstrated that Beta-galactosidase can be deactivated and reactivated with EDTA and divalent metal ions. The enzyme was deactivated after 20 minutes in EDTA solution. Maximal deactivation at the lowest EDTA concentration (10-3 mol.L-1) occurred in the presence of Tris-HCl buffer (pH 7.0). The enzyme recovered 50% of its initial activity after 10 minutes at Mg2+concentrations higher than 0.1 mmol.L-1. Experimental concentrations of 0.1 mmol.L-1 Mn2+ and 1.0 mmol.L-1 Co2+ were sufficient to reactivate the enzyme to around 300% of the control activity for the Mn2+ ion and nearly 100% for the Co2+ ion. The enzyme gradually lost its activity when the Co2+ concentration was 10-2 mol.L-1. Ni2+ and Zn2+ were unable to restore the catalytic activity. Km app and Vmax app were 1.95 ± 0.05 mmol.L-1 and 5.40 ± 0.86x10-2 mmol.min-1.mg-1, with o-NPG as substrate. Optimal temperature and pH were 34oC and 7.5. The half-life (t1/2) at 30ºC was 17.5 min for the holoenzyme and 11.0 min for the apoenzyme. With respect to pH variation, the apoenzyme proved to be more sensitive than the holoenzyme.


Assuntos
Humanos , Ácido Edético , Kluyveromyces , beta-Galactosidase/isolamento & purificação , Ativação Enzimática
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