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1.
J Environ Manage ; 336: 117664, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36921470

RESUMO

The increase in energy and fertilizer consumption makes it necessary to develop sustainable alternatives for agriculture. Anaerobic digestion and digestates appeared to be suitable options. However, untreated digestates still have high water content and can increase greenhouse gas emissions during storage and land application. In this study, manure-derived digestate and solid fraction of digestate after separation were treated with a novel solar drying technology to reduce their water content, combined with acidification to reduce the gaseous emissions. The acidified digestate and acidified solid fraction of digestate recovered more nitrogen and ammonia nitrogen than their respective non-acidified products (1.5-1.3 times for TN; 14 times for TAN). Ammonia and methane emissions were reduced up to 94% and 72% respectively, compared to the non-acidified ones, while N2O increased more than 3 times. Dried digestate and dried acidified digestate can be labeled as NPK organic fertilizer regarding the European regulation, and the dried solid fraction and the improved dried acidified solid fraction can be labeled as N or P organic fertilizer. Moreover, plant tests showed that N concentrations in fresh lettuce leaves were within the EU limit with all products in all the cases. However, zinc concentration appeared to be a limitation in some of the products as their concentration exceeded the European legal limits.


Assuntos
Amônia , Esterco , Fertilizantes , Agricultura , Nitrogênio/análise , Concentração de Íons de Hidrogênio , Água , Anaerobiose
2.
Arch Toxicol ; 96(6): 1815-1827, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35428896

RESUMO

Human Precision-cut intestinal slices (hPCIS) are used to study intestinal physiology, pathophysiology, drug efficacy, toxicology, kinetics, and metabolism. However, the use of this ex vivo model is restricted to approximately a 24 h timeframe because of declining viability of the hPCIS during traditional culture. We hypothesized that we could extend the hPCIS viability by using organoid medium. Therefore, we cultured hPCIS for up to 72 h in organoid media [expansion medium (Emed) and differentiation medium (Dmed)]. After incubation, we assessed culture-induced changes on viability markers, specific cell type markers and we assessed the metabolic activity of enterocytes by measuring midazolam metabolite formation. We show that the adenosine triphosphate (ATP)/protein ratio of Emed-cultured hPCIS and morphology of both Emed- and Dmed-cultured hPCIS was improved compared to WME-cultured hPCIS. Emed-cultured hPCIS showed an increased expression of proliferation and stem cell markers, whereas Dmed-cultured hPCIS showed an increased expression of proliferation and enterocyte markers, along with increased midazolam metabolism. Using the Emed, the viability of hPCIS could be extended for up to 72 h, and proliferating stem cells remained preserved. Using Dmed, hPCS also remained viable for up to 72 h, and specifically rescued the metabolizing enterocytes during culture. In conclusion, by using two different organoid culture media, we could extend the hPCIS viability for up to 72 h of incubation and specifically steer stem cells or enterocytes towards their original function, metabolism, and proliferation, potentially allowing pharmacokinetic and toxicology studies beyond the 24 h timeframe.


Assuntos
Intestinos , Midazolam , Meios de Cultura , Humanos , Inativação Metabólica , Midazolam/farmacologia , Organoides
3.
Tree Physiol ; 37(4): 441-455, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27885172

RESUMO

Isohydry (i.e., strong regulation of leaf water potential, Ψl) is commonly associated with strict stomatal regulation of transpiration under drought, which in turn is believed to minimize hydraulic risk at the expense of reduced carbon assimilation. Hence, the iso/anisohydric classification has been widely used to assess drought resistance and mortality mechanisms across species, with isohydric species being hypothetically more prone to carbon starvation and anisohydric species more vulnerable to hydraulic failure. These hypotheses and their underlying assumptions, however, have rarely been tested under controlled, experimental conditions. Our objective is to assess the physiological mechanisms underlying drought resistance differences between two co-occurring Mediterranean forest species with contrasting drought responses: Phillyrea latifolia L. (anisohydric and more resistant to drought) and Quercus ilex L. (isohydric and less drought resistant). A total of 100 large saplings (50 per species) were subjected to repeated drought treatments for a period of 3 years, after which Q. ilex showed 18% mortality whereas no mortality was detected in P. latifolia. Relatively isohydric behavior was confirmed for Q. ilex, but higher vulnerability to cavitation in this species implied that estimated embolism levels were similar across species (12-52% in Q. ilex vs ~30% in P. latifolia). We also found similar seasonal patterns of stomatal conductance and assimilation between species. If anything, the anisohydric P. latifolia tended to show lower assimilation rates than Q. ilex under extreme drought. Similar growth rates and carbon reserves dynamics in both species also suggests that P. latifolia was as carbon-constrained as Q. ilex. Increasing carbon reserves under extreme drought stress in both species, concurrent with Q. ilex mortality, suggests that mortality in our study was not triggered by carbon starvation. Our results warn against making direct connections between Ψl regulation, stomatal behavior and the mechanisms of drought-induced mortality in plants.


Assuntos
Carbono/metabolismo , Secas , Oleaceae/fisiologia , Quercus/fisiologia , Água/fisiologia , Florestas , Folhas de Planta/fisiologia , Transpiração Vegetal
4.
J Cereb Blood Flow Metab ; 9(4): 523-34, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2661584

RESUMO

Fourteen patients were studied by positron emission tomography (PET) within 48 h of onset of a hemispheric ischemic stroke and again 7 days later. After the first set of PET scans, the patients were randomized to receive either nimodipine (n = 7) or a carrier solution (n = 7) by intravenous infusion. The infusions were maintained until the end of the second PET studies. CBF, cerebral blood volume (CBV), oxygen extraction ratio (OER), CMRO2, and CMRglc were measured each time. These metabolic and perfusion measurements were performed by standard methods. A surface map of each metabolic and perfusion measurement in the cortical mantle was generated by interpolating between the available slices. The various surface maps representing the physiological characteristics determined in the same or subsequent studies were aligned so that all data sets could be analyzed identically using an array of square regions of interest (ROIs). The functional status of each ROI was recorded at the two intervals following the cerebrovascular accident to characterize the evolution of the infarct, penumbra, and normal brain regions. We presumed the ischemic penumbra to be cortical regions in the proximity of the infarct and perfused at CBF values between 12 and 18 ml/100 g/min on the first PET scan, while densely ischemic regions had CBF of less than 12 nl/100 g/min and normally perfused brain greater than 18 ml/100 g/min. In the densely ischemic zone, CBF increased more in the nimodipine-treated group than in the carrier group. As well, in this region nimodipine reversed the decline in CMRO2 noted in the carrier group, the difference in the changes being significant. In the penumbra zone, comparable trends were noted in OER and CMRO2 but the difference in the changes between the two groups did not reach statistical significance. Changes in CMRglc and CBV were comparable between the two groups in both cortical regions.


Assuntos
Infarto Cerebral/fisiopatologia , Nimodipina/farmacologia , Tomografia Computadorizada de Emissão , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Isquemia Encefálica/fisiopatologia , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nimodipina/administração & dosagem , Perfusão
5.
Rev. chil. cir ; 39(1): 59-61, 1987. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-58883

RESUMO

Se comunican tres casos de hemorragia gástrica masiva por ruptura de malformaciones arteriales de submucosas, en los que una endoscopia previa había diagnosticado y localizado la lesión. Dos de ellos fueron operados en intervalos y el tercero se operó inmediatamente después de un nuevo sangramiento sin estar sangrado activamente en el momento quirúrgico. En los tres casos se efectuó gastrotomía lográndose encontrar la lesión gracias a la información endoscópica. El tratamiento consistió en una resección en cuña lo cual permitió el diagnóstico histopatológico. Después de 18,20 y 35 meses de observación, los pacientes no han vuelto a sangrar


Assuntos
Adolescente , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Malformações Arteriovenosas , Hemorragia Gastrointestinal/etiologia , Ruptura Espontânea/complicações , Hemorragia Gastrointestinal/diagnóstico , Gastroscopia , Gastrostomia
6.
Rev. chil. pediatr ; 52(4): 289-92, 1981.
Artigo em Espanhol | LILACS | ID: lil-2666

RESUMO

Se practican 25 endoscopias digestivas altas a 18 ninos portadores de Hemorragia Digestiva o dolor abdominal recurrente, encontrando 4 ulceras duodenales agudas, 4 duodenitis erosivas, 4 gastritis erosivas, y 13 examenes normales (de estos, 7 son controles). Se describen detalladamente el aparato usado, la tecnica empleada y los resultados obtenidos en este estudio.Se concluye que este procedimiento es de alta utilidad diagnostica en patologia especifica, facil de realizar en manos de un endoscopista experto e inocuo para el paciente


Assuntos
Endoscopia , Hemorragia Gastrointestinal
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