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1.
Cryobiology ; 114: 104839, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38097056

RESUMO

Vitrification is a promising approach for ice-free cryopreservation of biological material, but progress is hindered by the limited set of experimental tools for studying processes in the interior of the vitrified matter. Isochoric cryopreservation chambers are often metallic, and their opacity prevents direct visual observation. In this study, we introduce photon counting X-ray computed tomography (CT) to compare the effects of rigid isochoric and unconfined isobaric conditions on vitrification and ice formation during cooling of two aqueous solutions: 50 wt% DMSO and a coral vitrification solution, CVS1. Previous studies have only compared vitrification in isochoric systems with isobaric systems that have an exposed air-liquid interface. We use a movable piston to replicate the surface and thermal boundary conditions of the isochoric system yet maintain isobaric conditions. When controlling for the boundary conditions we find that similar ice and vapor volume fractions form during cooling in isochoric and isobaric conditions. Interestingly, we observe distinct ice and vapor cavity morphology in the isochoric systems, possibly due to vapor outgassing or cavitation as rapid cooling causes the pressure to drop in the confined systems. These observations highlight the array of thermal-fluid processes that occur during vitrification in confined aqueous systems and motivate the further application of imaging techniques such as photon counting X-ray CT in fundamental studies of vitrification.


Assuntos
Criopreservação , Vitrificação , Criopreservação/métodos , Congelamento , Raios X , Água , Tomografia Computadorizada por Raios X , Crioprotetores/farmacologia
2.
Cryobiology ; 116: 104935, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38936595

RESUMO

Isochoric (constant-volume or volumetrically confined) vitrification has shown potential as an alternative cryopreservation-by-vitrification technique, but the complex processes at play within the chamber are yet poorly characterized, and recent investigations have prompted significant debate around whether a truly isochoric vitrification process (in which the liquid remains completely confined by solid boundaries) is indeed feasible. Based on a recent thermomechanical simulation of a high-concentration Me2SO solution, Solanki and Rabin (Cryobiology, 2023, 111, 9-15.) argue that isochoric vitrification is not feasible, because differential thermal contraction of the solution and container will necessarily drive generation of a cavity, corrupting the rigid confinement of the liquid. Here, we provide direct experimental evidence to the contrary, demonstrating cavity-free isochoric vitrification of a ∼3.5 M vitrification solution by combined isochoric pressure measurement (IPM) and photon-counting x-ray computed tomography (PC-CT). We hypothesize that the absence of a cavity is due to the minimal thermal contraction of the solution, which we support with additional volumetric analysis of the PC-CT reconstructions. In total, this study provides experimental evidence both demonstrating the feasibility of isochoric vitrification and highlighting the potential of designing vitrification solutions that exhibit minimal thermal contraction.

3.
Actas Dermosifiliogr ; 113(5): 459-466, 2022 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35697405

RESUMO

BACKGROUND AND OBJECTIVE: Psoriasis is a multisystem disease associated with an increased prevalence of oral lesions. The aim of this study was to determine the prevalence of oral lesions in patients with psoriasis and examine associations with clinical and patient characteristics. MATERIAL AND METHODS: We conducted a cross-sectional study of patients with psoriasis and healthy controls seen between December 2019 and February 2020. We recorded biometric data, comorbidities associated with psoriasis, oral examination findings, and clinical characteristics of psoriasis. RESULTS: We studied 100 patients with psoriasis and 100 controls. Oral lesions were more common in the psoriasis group (74% vs 46%, P<.001). The most common lesions were fissured tongue (39% vs 16%, P<.001) and periodontitis (28% vs 16%, P=.04). Geographic tongue was uncommon in both the study and the control group (4% vs 2%, P=.68). In the psoriasis group, patients with fissured tongue had a higher prevalence of cardiovascular disease (23.1% vs 4.9%), diabetes mellitus (28.2% vs 8.2%), and psoriatic arthritis (15.4% vs 1.6%) than those without this condition. Periodontitis was also associated with a higher prevalence of cardiovascular disease (28.6% vs 5.6%). Type of psoriasis, location, and time since onset were not significantly associated with oral lesions. Patients with oral lesions, however, had more severe disease (Psoriasis Area Severity Index [PASI], 3.9 vs 2.4; P=.05). Mean PASI was also higher in patients with fissured tongue (4.7 vs. 2.7, P=.03) and periodontitis (5.1 vs. 2.9, P=.04). CONCLUSIONS: The prevalence of oral lesions, especially fissured tongue and periodontitis, is higher in patients with psoriasis than in healthy controls. Oral lesions were associated with more severe psoriasis and a higher prevalence of associated comorbidities. We recommend examining the oral cavity of patients with psoriasis, especially those with more severe disease and comorbidities, irrespective of type of psoriasis, location, or time since onset.


Assuntos
Doenças Cardiovasculares , Periodontite , Psoríase , Doenças da Língua , Língua Fissurada , Doenças Cardiovasculares/complicações , Estudos Transversais , Humanos , Periodontite/complicações , Periodontite/epidemiologia , Prevalência , Psoríase/complicações , Psoríase/epidemiologia , Língua Fissurada/complicações , Língua Fissurada/etiologia
4.
J Opt Soc Am A Opt Image Sci Vis ; 37(11): C45-C49, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33175730

RESUMO

This contribution reports, for what we believe is the first time, on VO2-based thin-film coatings on flexible Al substrates exhibiting a tunable positive emittance-switching Δε=(εH-εL)>0. More precisely, a layered stack of a-Si:H/SiO2/VO2 on flexible Al sheets presents minimum and maximum values of emissivity of about 0.18 and 0.57 at 40ºC and 83ºC, respectively, and hence allows an emittance-switching Δε of 0.39 and a relative variation Δε/ÎµΛ of ∼217%. Such variations fit with the potential applications of such coatings as smart radiation devices in small satellites and spacecraft.

5.
Biotechnol Bioeng ; 114(11): 2528-2538, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28688186

RESUMO

Microbial production of plant derived, biologically active compounds has the potential to provide economic and ecologic alternatives to existing low productive, plant-based processes. Current production of the pharmacologically active cyclic triterpenoid betulinic acid is realized by extraction from the bark of plane tree or birch. Here, we reengineered the reported betulinic acid pathway into Saccharomyces cerevisiae and used this novel strain to develop efficient fermentation and product purification methods. Fed-batch cultivations with ethanol excess, using either an ethanol-pulse feed or controlling a constant ethanol concentration in the fermentation medium, significantly enhanced production of betulinic acid and its triterpenoid precursors. The beneficial effect of excess ethanol was further exploited in nitrogen-limited resting cell fermentations, yielding betulinic acid concentrations of 182 mg/L, and total triterpenoid concentrations of 854 mg/L, the highest concentrations reported so far. Purification of lupane-type triterpenoids with high selectivity and yield was achieved by solid-liquid extraction without prior cell disruption using polar aprotic solvents such as acetone or ethyl acetate and subsequent precipitation with strong acids. This study highlights the potential of microbial production of plant derived triterpenoids in S. cerevisiae by combining metabolic and process engineering.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Etanol/metabolismo , Engenharia Metabólica/métodos , Saccharomyces cerevisiae/fisiologia , Triterpenos/isolamento & purificação , Triterpenos/metabolismo , Reatores Biológicos/microbiologia , Fermentação/fisiologia , Redes e Vias Metabólicas/genética , Triterpenos Pentacíclicos , Saccharomyces cerevisiae/citologia , Ácido Betulínico
6.
AIDS Behav ; 18(4): 740-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23918244

RESUMO

We sought to examine whether methadone maintenance therapy (MMT) decreased rates of antiretroviral therapy (ART) discontinuation and was associated with plasma HIV RNA responses among a cohort of illicit drug users. Cumulative ART discontinuation rates were estimated using Kaplan-Meier methods and factors independently associated with ART discontinuation were identified using Cox proportional hazards regression. Engagement in MMT was negatively and independently associated with ART discontinuation [Adjusted Relative Hazard = 0.67 (95 % CI 0.54-0.83); p < 0.001]. Among participants receiving ART and MMT, 81.6 % of plasma HIV-1 RNA assessments were <500 copies/mL, while 65.81 % of HIV-1 RNA assessments among those prescribed ART without MMT were <500 copies/mL (p < 0.001). These results demonstrate that engagement in MMT conferred a protective benefit against ART discontinuation and was associated with a significant increase in plasma HIV RNA suppression among HIV-infected opioid-dependent drug users.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Drogas Ilícitas/efeitos adversos , Adesão à Medicação/estatística & dados numéricos , Metadona/administração & dosagem , Tratamento de Substituição de Opiáceos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto , Analgésicos Opioides/administração & dosagem , Contagem de Linfócito CD4 , Canadá/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Resultado do Tratamento , Carga Viral
7.
Sci Rep ; 14(1): 1512, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233437

RESUMO

Transcranial direct current stimulation combined with cognitive training (tDCS-cog) represents a promising approach to combat cognitive decline among healthy older adults and patients with mild cognitive impairment (MCI). In this 5-day-long double-blinded randomized trial, we investigated the impact of intensified tDCS-cog protocol involving two trains of stimulation per day on working memory (WM) enhancement in 35 amnestic and multidomain amnestic MCI patients. Specifically, we focused to improve WM tasks relying on top-down attentional control and hypothesized that intensified tDCS would enhance performance of visual object matching task (VOMT) immediately after the stimulation regimen and at a 1-month follow-up. Secondarily, we explored whether the stimulation would augment online visual working memory training. Using fMRI, we aimed to elucidate the neural mechanisms underlying the intervention effects by analyzing BOLD activations during VOMT. Our main finding revealed no superior after-effects of tDCS-cog over the sham on VOMT among individuals with MCI as indicated by insignificant immediate and long-lasting after-effects. Additionally, the tDCS-cog did not enhance online training as predicted. The fMRI analysis revealed brain activity alterations in right insula that may be linked to tDCS-cog intervention. In the study we discuss the insignificant behavioral results in the context of the current evidence in tDCS parameter space and opening the discussion of possible interference between trained cognitive tasks.


Assuntos
Disfunção Cognitiva , Estimulação Transcraniana por Corrente Contínua , Humanos , Idoso , Estimulação Transcraniana por Corrente Contínua/métodos , Córtex Pré-Frontal Dorsolateral , Encéfalo/diagnóstico por imagem , Memória de Curto Prazo/fisiologia , Disfunção Cognitiva/terapia , Córtex Pré-Frontal/fisiologia , Método Duplo-Cego
8.
Sci Rep ; 14(1): 2818, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38307893

RESUMO

Solar heat management & green air-conditioning are among the major technologies that could mitigate heat islands phenomenon while minimizing significantly the CO2 global foot-print within the building & automotive sectors. Chromogenic materials in general, and thermochromic smart coatings especially are promising candidates that consent a noteworthy dynamic solar radiation Infrared (NIR-IR) regulation and hence an efficient solar heat management especially with the expected increase of the global seasonal temperature. Within this contribution, two major challenging bottlenecks in vanadium oxide based smart coatings were addressed. It is validated for the first time that the NIR-IR modulation of the optical transmission (∆TTRANS = T(T〈TMIT) - T(T〉TMIT) of Vanadium oxide based smart coatings can be controlled & tuned. This upmost challenging bottle-neck controllability/tunability is confirmed via a genuine approach alongside to a simultaneous drastic reduction of the phase transition temperature TMIT from 68.8 °C to nearly room temperature. More precisely, a substantial thermochromism in multilayered V2O5/V/V2O5 stacks equivalent to that of standard pure VO2 thin films but with a far lower transition temperature, is reported. Such a multilayered V2O5/V/V2O5 thermochromic system exhibited a net control & tunability of the optical transmission modulation in the NIR-IR (∆TTRANS) via the nano-scaled thickness' control of the intermediate Vanadium layer. In addition, the control of ∆TTRANS is accompanied by a tremendous diminution of the thermochromic transition temperature from the elevated bulk value of 68.8 °C to the range of 27.5-37.5 ºC. The observed remarkable and reversible thermochromism in such multilayered nano-scaled system of V2O5/V/V2O5 is likely to be ascribed to a noteworthy interfacial diffusion, and an indirect doping by alkaline ions diffusing from the borosilicate substrate. It is hoped that the current findings would contribute in advancing thermochromic smart window technology and their applications for solar heat management in glass windows in general, skyscraper especially & in the automotive industry. If so, this would open a path to a sustainable green air-conditioning with zero-energy input.

9.
Front Pharmacol ; 14: 1186016, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324473

RESUMO

Multiple sclerosis (MS) and inflammatory bowel disease (IBD) are autoimmune disorders characterized by inflammatory episodes affecting the brain and the gastrointestinal (GI) tract, respectively. The frequent association between MS and IBD suggests that both conditions may share common pathogenic mechanisms. However, different responses to biological therapies indicate differences in immune mechanisms of inflammation. Anti-CD20 therapies are high efficacy treatments increasingly used to control inflammatory bursts in MS, but they may alter GI homeostasis and promote the development of bowel inflammation in susceptible individuals. This review analyzes the mechanistic association between immunity in MS and IBD, the effect of anti-CD20 therapies on the gut microenvironment, and provides recommendations for early detection and management of GI toxicities in the context of B-cell depletion in MS patients.

11.
Gastroenterol Clin Biol ; 32(8-9): 734-9, 2008.
Artigo em Francês | MEDLINE | ID: mdl-18774251

RESUMO

SUMMARY: Septic pylephlebitis is usually a complication of intraabdominal infection in the region drained by the portal venous system. We report two cases of portal and mesenteric venous thrombosis associated with Fusobacterium necrophorum bacteremia, which did not show any obvious intra-abdominal source of infection with noninvasive imaging procedures. In one case, early anticoagulation treatment was associated with repermeation of the portal vein and its right branch. As in Bacteroides bacteremia, portal and/or mesenteric venous thrombosis should be searched for in case of Fusobacterium bacteremia of unknown origin. Repermeation of the portal vein and relief of extrahepatic portal hypertension can be achieved in these cases with early anticoagulation.


Assuntos
Bacteriemia/complicações , Infecções por Fusobacterium/complicações , Veias Mesentéricas , Veia Porta , Trombose Venosa/microbiologia , Adulto , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
12.
Radiat Prot Dosimetry ; 178(3): 254-259, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981719

RESUMO

Operational measures taken for the repatriation of Alcyon II 60Co Teletherapy head and El Dorado 6 60Co Teletherapy devices located in Yaounde and Douala respectively are reported. Operations carried out have permit to store Alcyon head in the CC 33 container and to transfer 60Co source from El Dorado 6 device to YKT1B container. These containers are approved as Type B package for securely transport. Optically stimulated luminescence dosimeters had been distributed to all involved persons to estimate the received effective dose during operations. It appears by the present study that, the most received individual effective dose is 130 µSv during the whole process.


Assuntos
Exposição Ambiental/prevenção & controle , Exposição Ocupacional/prevenção & controle , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Resíduos Radioativos , Gerenciamento de Resíduos/métodos , Camarões , Humanos , Doses de Radiação , Gerenciamento de Resíduos/instrumentação
13.
Br J Pharmacol ; 152(1): 151-60, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17603549

RESUMO

BACKGROUND AND PURPOSE: Blockade of AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptors is a good treatment option for a variety of central nervous system disorders. The present study evaluated the neuroprotective and anticonvulsant effects of EGIS-8332, a non-competitive AMPA receptor antagonist, as a potential drug candidate. EXPERIMENTAL APPROACH: AMPA antagonist effects of EGIS-8332 were measured using patch-clamp techniques. Neuroprotective and anticonvulsant effects of EGIS-8332 were evaluated in various experimental models, relative to those of GYKI 53405. KEY RESULTS: EGIS-8332 inhibited AMPA currents in rat cerebellar Purkinje cells and inhibited the AMPA- and quisqualate-induced excitotoxicity in primary cultures of telencephalon neurons (IC(50)=5.1-9.0 microM), in vitro. Good anticonvulsant actions were obtained in maximal electroshock-, sound- and chemically-induced seizures (range of ED(50)=1.4-14.0 mg kg(-1) i.p.) in mice. Four days after transient global cerebral ischaemia, EGIS-8332 decreased neuronal loss in the hippocampal CA1 area in gerbils and rats. EGIS-8332 dose-dependently reduced cerebral infarct size after permanent middle cerebral artery occlusion in mice and rats (minimum effective dose=3 mg kg(-1) i.p.). Side effects of EGIS-8332 emerged much above its pharmacologically active doses. A tendency for better efficacy of GYKI 53405 than that of EGIS-8332 was observed in anticonvulsant tests that reached statistical significance in few cases, while the contrary was perceived in cerebral ischaemia tests. CONCLUSIONS AND IMPLICATIONS: EGIS-8332 seems suitable for further development for the treatment of epilepsy, ischaemia and stroke based on its efficacy in a variety of experimental disease models, and on its low side effect potential.


Assuntos
Anticonvulsivantes/farmacologia , Benzodiazepinas/farmacologia , Isquemia Encefálica/prevenção & controle , Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Receptores de AMPA/antagonistas & inibidores , Convulsões/prevenção & controle , Animais , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapêutico , Benzodiazepinas/metabolismo , Benzodiazepinas/uso terapêutico , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Agonistas de Aminoácidos Excitatórios/toxicidade , Gerbillinae , Masculino , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos DBA , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/uso terapêutico , Técnicas de Patch-Clamp , Células de Purkinje/efeitos dos fármacos , Células de Purkinje/metabolismo , Ácido Quisquálico/toxicidade , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Receptores de AMPA/metabolismo , Convulsões/etiologia , Convulsões/metabolismo , Telencéfalo/efeitos dos fármacos , Telencéfalo/metabolismo , Fatores de Tempo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/metabolismo
14.
Stat Methods Med Res ; 16(6): 497-522, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17698932

RESUMO

This work describes the application of a spatio-temporal modeling to the study of glaucoma, a very serious ocular illness. The aim of this modeling is to solve various significant medical problems, namely the forecasting of future observations, the classification of observations as normal or defective, and the simulation of new longitudinal data sets. In order to ascertain whether a patient suffers from glaucoma, a perimetry is performed. The output of a perimetry is called a visual field and consists of a map with 52 numerical values plotted on a regular grid. In this work, a data set of healthy patients' visual fields is used. The work begins with an exploratory spatial data analysis. A semi-parametric approach is used to model the mean, and the variogram is fitted using a Matérn function. Once the spatial structure has been analysed, the spatial mean is subtracted from all the observations in the data set and the spatio-temporal correlation of the residuals is explored. All this information is used to build a space-time model, the parameters of which are estimated by maximum likelihood. Different methods are used to check the goodness of fit.


Assuntos
Modelos Estatísticos , Testes de Campo Visual/estatística & dados numéricos , Glaucoma/diagnóstico , Humanos , Espanha
15.
Biotechnol J ; 11(5): 717-24, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26710256

RESUMO

Melatonin is a natural mammalian hormone that plays an important role in regulating the circadian cycle in humans. It is a clinically effective drug exhibiting positive effects as a sleep aid and a powerful antioxidant used as a dietary supplement. Commercial melatonin production is predominantly performed by complex chemical synthesis. In this study, we demonstrate microbial production of melatonin and related compounds, such as serotonin and N-acetylserotonin. We generated Saccharomyces cerevisiae strains that comprise heterologous genes encoding one or more variants of an L-tryptophan hydroxylase, a 5-hydroxy-L-tryptophan decarboxylase, a serotonin acetyltransferase, an acetylserotonin O-methyltransferase, and means for providing the cofactor tetrahydrobiopterin via heterologous biosynthesis and recycling pathways. We thereby achieved de novo melatonin biosynthesis from glucose. We furthermore accomplished increased product titers by altering expression levels of selected pathway enzymes and boosting co-factor supply. The final yeast strain produced melatonin at a titer of 14.50 ± 0.57 mg L(-1) in a 76h fermentation using simulated fed-batch medium with glucose as sole carbon source. Our study lays the basis for further developing a yeast cell factory for biological production of melatonin.


Assuntos
Glucose/metabolismo , Melatonina/biossíntese , Engenharia Metabólica/métodos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/genética , Animais , Técnicas de Cultura Celular por Lotes , Vias Biossintéticas , Meios de Cultura/química , Fermentação , Humanos , Microbiologia Industrial/métodos , Saccharomyces cerevisiae/enzimologia , Serotonina/análogos & derivados , Serotonina/biossíntese
16.
Waste Manag ; 36: 277-88, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25488733

RESUMO

This paper reports on a project focused on obtaining the current consumption and disposal habits of electrical and electronic toys from a survey aimed at parents of children of nine pre- and primary schools. In addition, it is also focused on identifying the most effective way of transmitting environmental information to parents and children to promote the collection of electrical and electronic toys at their end-of-life. The study was implemented in a Spanish municipality. With regard to the consumption habits, aspects related to the amount of toys that children receive annually and percentage of those which are electrical and electronic toys have been obtained and classified according to the family size. Results from Chi-squared analysis and Ordinal Logistic Regression show that there is a statistically significance relationship among these variables. Regarding disposal habits, aspects related to the reasons and way for discarding electrical and electronic toys, time that toys are kept at home or the willingness to rent or buy second hand e-toys have been obtained. What really attracts attention is that, apart from consumers who donate the toy to family or social associations, 67.1% of consumers discard them along with other waste fractions in domestic bins, whereas only 32.9% do so at recycling points, as Directive 2012/19/EU requires. To increase this percentage, three environmental education actions (distinguishing from each other by the way used to transmit the environmental information: paper, audiovisual or personal communication) have been designed, applied and evaluated their efficiency according to the amount of waste toys collected.


Assuntos
Comportamento do Consumidor , Educação , Resíduo Eletrônico/análise , Meio Ambiente , Jogos e Brinquedos , Adulto , Criança , Pré-Escolar , Conservação dos Recursos Naturais , Humanos , Jogos e Brinquedos/psicologia , Espanha
17.
Med Biol Eng Comput ; 53(7): 623-33, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25773368

RESUMO

Erythrocyte shape deformations are related to different important illnesses. In this paper, we focus on one of the most important: the Sickle cell disease. This disease causes the hardening or polymerization of the hemoglobin that contains the erythrocytes. The study of this process using digital images of peripheral blood smears can offer useful results in the clinical diagnosis of these illnesses. In particular, it would be very valuable to find a rapid and reproducible automatic classification method to quantify the number of deformed cells and so gauge the severity of the illness. In this paper, we show the good results obtained in the automatic classification of erythrocytes in normal cells, sickle cells, and cells with other deformations, when we use a set of functions based on integral-geometry methods, an active contour-based segmentation method, and a k-NN classification algorithm. Blood specimens were obtained from patients with Sickle cell disease. Seventeen peripheral blood smears were obtained for the study, and 45 images of different fields were obtained. A specialist selected the cells to use, determining those cells which were normal, elongated, and with other deformations present in the images. A process of automatic classification, with cross-validation of errors with the proposed descriptors and with other two functions used in previous studies, was realized.


Assuntos
Eritrócitos/classificação , Eritrócitos/citologia , Eritrócitos/patologia , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Anemia Falciforme/patologia , Forma Celular , Humanos , Microscopia
18.
Pediatr Infect Dis J ; 9(8): 551-5, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2235170

RESUMO

The nosocomial spread of enteric pathogens is often difficult to control in overcrowded pediatric wards. During 1983 and 1984, despite cohorting of patients and enforced hand washing, more than 200 cases of nosocomial multiply resistant Salmonella typhimurium phage type R-9 were observed on two adjacent pediatric wards. Most cases occurred during the summer months. After 19 new cases were detected early in the summer of 1985, oral administration of furazolidone throughout their entire hospital stay (2.5 mg/kg twice daily) was recommended for all subsequently hospitalized infants. Among the 114 (65%) infants who were appropriately treated, only one additional case (1%) was detected. In contrast 11 (19%) cases occurred among the 59 infants who were inappropriately treated: 5 of 35 (14%) of those who were not treated and 6 of 24 (25%) in whom treatment with furazolidone was delayed greater than 24 hours (P less than 0.001 between the appropriately and inappropriately treated groups). In pediatric wards where infection control measures cannot be optimally applied, prophylactic furazolidone administration may be helpful in preventing the spread of enteric pathogens.


Assuntos
Infecção Hospitalar/epidemiologia , Furazolidona/uso terapêutico , Infecções por Salmonella/epidemiologia , Estudos de Coortes , Infecção Hospitalar/prevenção & controle , Surtos de Doenças , Tolerância a Medicamentos , Fezes/microbiologia , Humanos , Lactente , Israel/epidemiologia , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/prevenção & controle , Salmonella typhimurium/classificação , Salmonella typhimurium/efeitos dos fármacos , Estados Unidos/epidemiologia
19.
Brain Res Bull ; 50(3): 179-86, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10566979

RESUMO

The neuroprotective activity of the non-competitive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) antagonist GYKI-52466 (1-[4-aminophenyl]-4-methyl-7,8-methylene-dioxy-5H-2,3-benzodia zep ine HCI; EGIS-8159) was studied in the gerbil bilateral carotid occlusion (BCO) model of global ischemia. Drug effect on hippocampal CA1 neuronal loss, hypermotility, and cognitive deficit (decrease in spontaneous alternation (SA) behaviour in the Y-maze) induced by 5-min or 3-min BCO were measured. GYKI-52466 was administered at 4 x 15 mg/kg intraperitoneal (i.p.) doses 30, 45, 60, and 75 min following surgery. The competitive AMPA antagonist NBQX (2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)-quinoxaline) applied at 3 x 30 mg/kg i.p. doses 60, 70, and 85 min after reperfusion was also tested for comparison. Both compounds showed weak and non-significant effects on 5-min BCO-induced changes in all the three variables. However, following 3-min ischemia GYKI-52466 and NBQX produced significant inhibition (49% and 48%, respectively) on CA1 cell loss. Moreover, GYKI-52466, but not NBQX, significantly inhibited the 3-min ischemia induced hypermotility and decrease in SA. At their neuroprotective doses, both compounds caused long-lasting (min. 8 h) hypothermia in gerbils. GYKI-52466 induced much higher decrease in body temperature (6 degrees C at peak level) than NBQX did (2 degrees C at peak level). Administration of 4 x 10 mg/kg i.p. chlorpromazine to gerbils 15 min before and 0, 15, and 30 min after 3-min BCO resulted in considerable hypothermia (5.5 degrees C peak effect, 8 h duration), but no protective action of the compound on CA1 cell loss and hypermotility was observed. However, chlorpromazine inhibited the ischemia-induced cognitive impairment. The results suggest that drug-induced hypothermia may differentially influence the histological and the behavioural outcomes of ischemic intervention.


Assuntos
Ansiolíticos/farmacologia , Benzodiazepinas , Antagonistas de Aminoácidos Excitatórios/farmacologia , Ataque Isquêmico Transitório/fisiopatologia , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Receptores de AMPA/antagonistas & inibidores , Animais , Temperatura Corporal/efeitos dos fármacos , Clorpromazina/farmacologia , Gerbillinae , Ataque Isquêmico Transitório/psicologia , Masculino , Quinoxalinas/farmacologia , Fatores de Tempo
20.
Waste Manag ; 34(12): 2434-44, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25266157

RESUMO

European waste legislation has been encouraging for years the incorporation of selective collection systems for the biowaste fraction. European countries are therefore incorporating it into their current municipal solid waste management (MSWM) systems. However, this incorporation involves changes in the current waste management habits of households. In this paper, the attitude of the public towards the incorporation of selective collection of biowaste into an existing MSWM system in a Spanish municipality is analysed. A semi-structured telephone interview was used to obtain information regarding aspects such as: level of participation in current waste collection systems, willingness to participate in selective collection of biowaste, reasons and barriers that affect participation, willingness to pay for the incorporation of the selective collection of biowaste and the socioeconomic characteristics of citizens who are willing to participate and pay for selective collection of biowaste. The results showed that approximately 81% of the respondents were willing to participate in selective collection of biowaste. This percentage would increase until 89% if the Town Council provided specific waste bins and bags, since the main barrier to participate in the new selective collection system is the need to use specific waste bin and bags for the separation of biowaste. A logit response model was applied to estimate the average willingness to pay, obtaining an estimated mean of 7.5% on top of the current waste management annual tax. The relationship of willingness to participate and willingness to pay for the implementation of this new selective collection with the socioeconomic variables (age, gender, size of the household, work, education and income) was analysed. Chi-square independence tests and binary logistic regression was used for willingness to participate, not being obtained any significant relationship. Chi-square independence tests, ordinal logistic regression and ordinary linear regression was applied for willingness to pay, obtaining statistically significant relationship for most of the socioeconomic variables.


Assuntos
Atitude , Resíduos Sólidos/análise , Gerenciamento de Resíduos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Espanha
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