515 research outputs found
NMR quantification of 16-O-methylcafestol and kahweol in Coffea canephora var. robusta beans from different geographical origins
Diterpenes have recently received a great deal of interest as tools to investigate the botanical origin of coffee. Specifically, kahweol has been proposed as a marker of Coffea arabica while 16-O-methylcafestol (16-OMC) is a Coffea canephora specific marker and its detection and quantification allow the authenticity of pure C. arabica roasted coffee blends to be assessed. In this study, we evaluated the possibility of the industrial use of the quantification of these diterpenes to assess the relative amounts of the two coffee species in blends. The content of 16-OMC and kahweol was determined in 78 samples (i.e., 39 green and the corresponding 39 roasted beans) of C. canephora from different geographical origins using a recently published NMR approach. Our results show a small natural variability in 16-OMC content for the Asian samples (average content = 1837 \ub1 113 mg/kg) while a much larger spread was found for the African samples (average content = 1744 \ub1 322 mg/kg). This large variability prevents the use of 16-OMC to quantify C. canephora in unknown roasted coffee blends. We also show that kahweol cannot be considered a specific C. arabica marker since it was detected almost all coffees and quantified in about 30% of the C. canephora samples
Hepatic PPARs: their role in liver physiology, fibrosis and treatment
Complex molecular and cellular mechanisms are involved in the pathway of liver fibrosis. Activation and transformation of hepatic stellate cells (HSCs) are considered the two main reasons for the cause and development of liver fibrosis. The peroxisome proliferator-activated receptors (PPARs) belonging to the family of ligand-activated transcription factors play a key role in liver homeostasis, regulating adipogenesis and inhibiting fibrogenesis in HSCs. Normal transcriptional function of PPARs contributes to maintain HSCs in quiescent phase. A reduced expression of PPARs in HSCs greatly induces a progression of liver fibrosis and an increased production of collagen. Here, we discuss role and function of PPARs and we take into consideration molecular factors able to reduce PPARs activity in HSCs. Finally, although further validations are needed, we illustrate novel strategies available from in vitro and animal studies on how some PPARs-agonists have been proved effective as antifibrotic substances in liver disease
Expression Patterns of TNFα, MAdCAM1, and STAT3 in Intestinal and Skin Manifestations of Inflammatory Bowel Disease.
Pathogenesis of cutaneous extraintestinal manifestations [EIM] in inflammatory bowel disease [IBD] remains elusive. Efficacy of anti-TNF agents suggests TNF-dependent mechanisms. The role of other biologics, such as anti-integrins or JAK-inhibitors, is not yet clear.
We performed immunohistochemistry for TNFα, NFκB, STAT1/STAT3, MAdCAM1, CD20/68, caspase 3/9, IFNγ, and Hsp-27/70 on 240 intestinal [55 controls, 185 IBD] and 64 skin biopsies [11 controls, 18 erythema nodosum [EN], 13 pyoderma gangenosum [PG], 22 psoriasis]. A semiquantitative score [0-100%] was used for evaluation.
TNFα was upregulated in intestinal biopsies from active Crohn`s disease [CD] vs controls [36.2 vs 12.1, p < 0.001], but not ulcerative colitis [UC: 17.9]. NFκB, however, was upregulated in intestinal biopsies from both active CD and UC [43.2 and 34.5 vs 21.8, p < 0.001 and p = 0.017, respectively]. TNFα and NFκB were overexpressed in skin biopsies from EN, PG, and psoriasis. No MAdCAM1 overexpression was seen in skin tissues, whereas it was upregulated in active UC vs controls [57.5 vs 35.4, p = 0.003]. STAT3 was overexpressed in the intestinal mucosa of active and non-active IBD, and a similar upregulation was seen in skin biopsies from EN [84.7 vs 22.3, p < 0.001] and PG [60.5 vs 22.3, p = 0.011], but not in psoriasis. Caspase 3 and CD68 overexpression in skin biopsies distinguished EN/PG from psoriasis and controls.
Upregulation of TNFα/NFκB in EN and PG is compatible with the efficacy of anti-TNF in EIM management. Data on overexpressed STAT3, but not MAdCAM1, support a rationale for JAK-inhibitors in EN and PG, while questioning the role of vedolizumab
Simulation of espresso coffee extraction using smoothed particle hydrodynamics
A mesoscopic model for the simulation of espresso extraction based on the Smoothed Particle Hydrodynamics method is presented. The model incorporates some essential features such as bimodal granulometry (fines-coarses) of the coffee bed, double (liquid/intra-granular) molecular diffusion and solid-liquid release mechanism. The porous structures (’coarses’) are modelled as stationary solid regions whereas the migration of cellular fragments (’fines’) is described by single-particles advected by the flow. The boundary filter is modelled as a buffer region where fines are immobilized while entering it, therefore providing a transient flow impedance. The model captures well the transient permeability of the coffee bed under direct-inverse discharge observed in experiments, showing the importance of fines migration on the hydrodynamics of the extraction. The concentration kinetics for different molecular compounds are also studied. The present work lays down the basis for the virtual analysis of coffee flavors by monitoring the hydrodynamic and microstructural effects on the balance of extracted key-odorant or taste-actives compounds in the beverage
Mesoscopic modelling and simulation of espresso coffee extraction
A mesoscopic model for the simulation of espresso extraction based on the Smoothed Particle Hydrodynamics method is presented. The model incorporates some essential features such as bimodal granulometry (fines-coarses) of the coffee bed, double (liquid/intra-granular) molecular diffusion and solid-liquid release mechanism. The porous structures ('coarses') are modelled as stationary solid regions whereas the migration of cellular fragments ('fines') is described by single-particles advected by the flow. The boundary filter is modelled as a buffer region where fines are immobilized while entering it, therefore providing a transient flow impedance. The model captures well the transient permeability of the coffee bed under direct-inverse discharge observed in experiments, showing the importance of fines migration on the hydrodynamics of the extraction. The concentration kinetics for different molecular compounds (i.e caffeine, trigonelline and chlorogenic acid) are compared to experimental data for a traditional espresso extraction, showing excellent results. The present work lays down the basis for the virtual analysis of coffee flavors by monitoring the hydrodynamic and microstructural effects on the balance of extracted key-odorant or taste-actives compounds in the beverage.Project RTI2018-094595-B-I00 funded by (AEI/FEDER, UE) and acronym “VIRHACOST
Eficiência de fungicidas para controle de giberela em trigo: resultados dos ensaios cooperativos - safra 2011.
O conjunto de ensaios instalados permitiu avaliar a eficiência de fungicidas no controle de giberela em diferentes níveis de ocorrência da doença. Considerando a variável composta índice de Giberela e os três locais de maior ocorrência de giberela (Castro - PR, Guarapuava - PR e Cruz Alta - RS) todos os fungicidas testados foram capazes de reduzir a ocorrência de giberela. Ainda considerando este conjunto de dados, a redução na ocorrência da doença implicou em maior manutenção da produtividade. Dada a interação observada entre tratamentos e ambiente, que levou a diferentes níveis de doença e de controle, e ainda considerando os dados de rendimento de grãos, não se pode concluir, neste primeiro ano de ensaios, que algum dos fungicidas utilizados seja indubitavelmente superior aos demais e com alta eficiência no controle de giberela do trigo.bitstream/item/72717/1/co-23-2012.pd
Dermoscopy of Pitted Keratolysis
Irritated hyperhidrotic soles with multiple small pits are pathognomonic for pitted keratolysis (PK). Here we show the dermatoscopic view of typical pits that can ensure the diagnosis. PK is a plantar infection caused by Gram-positive bacteria, particularly Corynebacterium. Increases in skin surface pH, hyperhidrosis, and prolonged occlusion allow these bacteria to proliferate. The diagnosis is fundamentally clinical and treatment generally consists of a combination of hygienic measures, correcting plantar hyperhidrosis and topical antimicrobials
Modeling the effect of flow-induced mechanical erosion during coffee filtration
The espresso extraction process involves a complex transport inside a geometry-changing porous medium. Large solid grains forming the majority of the porous medium can migrate, swell, and consolidate, and they can also morphologically change during flow, i.e., being mechanically eroded by hydrodynamic forces. These processes can, in turn, have a significant back-effect on the flow and the related coffee extraction profiles. In this article, we devise a bottom–up erosion model in the framework of smoothed dissipative particle dynamics to consider flow-induced morphological changes of the coffee grains. We assume that the coffee grains are not completely wetted and remain brittle. We found that heterogeneity in both the filtration direction and the transverse direction can be induced. The former is controlled by the angle of internal friction while the latter is controlled by both the cohesion parameter and the angle of internal friction. Not restricted to the modeling of espresso extraction, our model can also be applied to other eroding porous media. Our results suggest that, under ideal porous flow conditions, we can control the heterogeneity (in both the pressure drop direction and the transverse direction) of an eroding medium by tuning the yield characteristics of the eroding material
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