7-Keto-Cholesterol and Cholestan-3beta, 5alpha, 6beta-Triol Induce Eryptosis through Distinct Pathways Leading to NADPH Oxidase and Nitric Oxide Synthase Activation

BACKGROUND/AIMS: We showed that patho-physiological concentrations of either 7-keto-cholesterol (7-KC), or cholestane-3beta, 5alpha, 6beta-triol (TRIOL) caused the eryptotic death of human red blood cells (RBC), strictly dependent on the early production of reactive oxygen species (ROS). The goal of the current study was to assess the contribution of the erythrocyte ROS-generating enzymes, NADPH oxidase (RBC-NOX), nitric oxide synthase (RBC-NOS) and xanthine oxido-reductase (XOR) to the oxysterol-dependent eryptosis and pertinent activation pathways. METHODS: Phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, reactive oxygen/nitrogen species (RONS) and nitric oxide formation from 2',7'-dichloro-dihydrofluorescein (DCF-DA) and 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate (DAF-FM DA) -dependent fluorescence, respectively; Akt1, phospho-NOS3 Ser1177, and PKCζ from Western blot analysis. The activity of individual 7-KC (7 μM) and TRIOL (2, μM) on ROS-generating enzymes and relevant activation pathways was assayed in the presence of Diphenylene iodonium chloride (DPI), N-nitro-L-arginine methyl ester (L-NAME), allopurinol, NSC23766 and LY294002, inhibitors in this order of RBC-NOX, RBC-NOS, XOR and upstream regulatory proteins Rac GTPase and phosphoinositide3 Kinase (PI3K); hemoglobin oxidation from spectrophotometric analysis. RESULTS: RBC-NOX was the target of 7-KC, through a signaling including Rac GTPase and PKCζ, whereas TRIOL caused activation of RBC-NOS according to the pathway PI3K/Akt, with the concurrent activity of a Rac-GTPase. In concomitance with the TRIOL-induced .NO production, formation of methemoglobin with global loss of heme were observed, ascribable to nitrosative stress. XOR, activated after modification of the redox environment by either RBC-NOX or RBC-NOS activity, concurred to the overall oxidative/nitrosative stress by either oxysterols. When 7-KC and TRIOL were combined, they acted independently and their effect on ROS/RONS production and PS exposure appeared the result of the effects of the oxysterols on RBC-NOX and RBC-NOS. CONCLUSION: Eryptosis of human RBCs may be caused by either 7-KC or TRIOL by oxidative/nitrosative stress through distinct signaling cascades activating RBC-NOX and RBC-NOS, respectively, with the complementary activity of XOR; when combined, the oxysterols act independently and both concur to the final eryptotic effect

A Data Fusion Perspective on Human Motion Analysis Including Multiple Camera Applications

Proceedings of: 5th International Work-Conference on the Interplay Between Natural and Artificial Computation, (IWINAC 2013). Mallorca, Spain, June 10-14.Human motion analysis methods have received increasing attention during the last two decades. In parallel, data fusion technologies have emerged as a powerful tool for the estimation of properties of objects in the real world. This papers presents a view of human motion analysis from the viewpoint of data fusion. JDL process model and Dasarathy's input-output hierarchy are employed to categorize the works in the area. A survey of the literature in human motion analysis from multiple cameras is included. Future research directions in the area are identified after this review.Publicad

Anti-proliferative effect of main dietary phytosterols and \u3b2-cryptoxanthin alone or combined in human colon cancer Caco-2 cells through cytosolic Ca+2 \u2013 and oxidative stress induced apoptosis

\u3b2-cryptoxanthin (\u3b2-Cx) and phytosterols (Ps) have potential against different cancer types,including colon cancer. However, their combined action has not been reported so far. Human colon cancer Caco-2 cells were treated 24 h with \u3b2-Cx and/or main dietary Ps (\u3b2-sitosterol, campesterol and stigmasterol), alone or in combination, at concentrations compatible with physiological human serum levels. A decrease in cell viability due to apoptosis (rise in sub-G1 population and exposure of membrane phosphatidylserine) was accompanied with dephosphorylation of BAD, mitochondrial depolarization and caspase 3-dependent PARP cleavage, with intracellular Ca2+ influx and increase of RONS levels as initial triggers. Ps and \u3b2-Cx, alone or in combination showed anti-proliferative activity against human colon adenocarcinoma Caco-2 cells through the mitochondrial pathway of apoptosis. No additive or synergistic effects were observed.The importance of bioactivity-guided assays with mixtures of dietary bioactive compounds to determine their eventual interactions in the functional food context is demonstrated

Ratchet, pawl and spring Brownian motor

We present a model for a thermal Brownian motor based on Feynman's famous ratchet and pawl device. Its main feature is that the ratchet and the pawl are in different thermal baths and connected by an harmonic spring. We simulate its dynamics, explore its main features and also derive an approximate analytical solution for the mean velocity as a function of the external torque applied and the temperatures of the baths. Such theoretical predictions and the results from numerical simulations agree within the ranges of the approximations performed.Comment: Submitted to Physica

Anti-Eryptotic Activity of Food-Derived Phytochemicals and Natural Compounds

Human red blood cells (RBCs), senescent or damaged due to particular stress, can be removed by programmed suicidal death, a process called eryptosis. There are various molecular mechanisms underlying eryptosis. The most frequent is the increase in the cytoplasmic concentration of Ca2+ ions, later exposure of erythrocytes to oxidative stress, hyperosmotic shock, ceramide formation, stimulation of caspases, and energy depletion. Phosphatidylserine (PS) exposed by eryptotic RBCs due to interaction with endothelial CXC-Motiv-Chemokin-16/Scavenger-receptor, causes the RBCs to adhere to vascular wall with consequent damage to the microcirculation. Eryptosis can be triggered by various xenobiotics and endogenous molecules, such as high cholesterol levels. The possible diseases associated with eryptosis are various, including anemia, chronic kidney disease, liver failure, diabetes, hypertension, heart failure, thrombosis, obesity, metabolic syndrome, arthritis, and lupus. This review addresses and collates the existing ex vivo and animal studies on the inhibition of eryptosis by food-derived phytochemicals and natural compounds including phenolic compounds (PC), alkaloids, and other substances that could be a therapeutic and/or co-adjuvant option in eryptotic-driven disorders, especially if they are introduced through the diet

Antiproliferative effects of bioaccessible fractions of honeys from Sicilian black honeybee (Apis mellifera ssp. sicula) on human colorectal carcinoma cells

The aim of this study was to evaluate the antiproliferative activity of bioaccessible fractions (BFs) obtained by the internationally standardized INFOGEST static digestion method to Sicilian honeys of three distinct floral origins (Sulla, Thistle and Dill) and the Manuka honey (gold standard), and to compare their effects based on total polyphenol content (TPC). Differentiated CaCo-2 cells (intestinal-like) and non-differentiated CaCo-2 and HCT-116 colonic tumour-like cells were incubated for 24 h with BFs of honeys to test viability, apoptosis, mitochondrial membrane potential (MMP), ROS and cell cycle. TPC after digestion ranked in the following order: Dill > Thistle > Sulla > Manuka. No decrease in cell viability in differentiated CaCo-2 cells was observed, while a reduction to 25\u201385% (CaCo-2) and 20\u201380% (HCT-116) of viability was obtained. This descent in viability was caused by a cell cycle block with an increase in apoptosis through dissipation of MMP and raise in ROS levels, being Thistle and Dill the most effective honeys followed by Sulla and finally Manuka, in agreement with TPC after digestion

Atherosclerotic Plaque Segmentation Based on Strain Gradients: A Theoretical Framework

Background: Atherosclerotic plaque detection is a clinical and technological problem that has been approached by different studies. Nowadays, intravascular ultrasound (IVUS) is the standard used to capture images of the coronary walls and to detect plaques. However, IVUS images are difficult to segment, which complicates obtaining geometric measurements of the plaque. Objective: IVUS, in combination with new techniques, allows estimation of strains in the coronary section. In this study, we have proposed the use of estimated strains to develop a methodology for plaque segmentation. Methods: The process is based on the representation of strain gradients and the combination of the Watershed and Gradient Vector Flow algorithms. Since it is a theoretical framework, the methodology was tested with idealized and real IVUS geometries. Results: We achieved measurements of the lipid area and fibrous cap thickness, which are essential clinical information, with promising results. The success of the segmentation depends on the plaque geometry and the strain gradient variable (SGV) that was selected. However, there are some SGV combinations that yield good results regardless of plaque geometry such as ▽εvMises+▽εrθ, ▽εyy+▽εrr or ▽εmin+▽εTresca. These combinations of SGVs achieve good segmentations, with an accuracy between 97.10% and 94.39% in the best pairs. Conclusions: The new methodology provides fast segmentation from different strain variables, without an optimization step

Incidence, seasonality and serotypes of rotavirus in Gipuzkoa (Basque Country), Spain. A 14-year study

Over a 14-year period (1984–97) the presence of rotavirus in stool samples from children under 15 years with acute gastroenteritis was studied by enzymoimmunoanalysis. Serotyping (G1–G4) was performed using monoclonal antibodies. A total of 17348 children under 15 were investigated. Rotavirus was detected in 3637 (21·0%) specimens, 74·6% of which were from children younger than 2 years old. G1 and G4 were the most frequent serotypes. In 1991–7, the minimum incidence of rotavirus gastroenteritis in children under 4 years of age was 21·7 cases/1000 children/year. By the age of 5 years, at least 1 out of 11·3 children and probably 1 out of every 5–6 children in this area had experienced an episode of rotavirus gastroenteritis that required medical care. In the 1984–90 period a clear seasonality was not observed but in the second period of the study (1991–7), seasonality was marked, with peak activity in winter

Early microvascular and neural changes in patients with type 1 and type 2 diabetes mellitus without clinical signs of diabetic retinopathy

Purpose: To assess and compare early modifications in inner retinal layer thickness and optical coherence tomography angiography parameters in patients with diabetes mellitus (DM) Types 1 and 2 without clinical signs of diabetic retinopathy. Methods: Ninety eyes of 90 subjects (24 Type 1 DM, 36 Type 2 DM, and 30 healthy controls) were prospectively evaluated with spectral domain OCT, swept-source OCT angiography, and color fundus photography (on the same day). Retinal nerve fiber layer, ganglion cell layer (GCL+), and nerve fiber layer + GCL+ (GCL++) thickness were automatically determined by the instrument in the 1, 3, and 6 central mm. On OCT angiography, the following parameters were evaluated: area of foveal avascular zone, number of focally dilated endings of the capillaries (detected only on OCT angiography), presence of regular/irregular foveal avascular zone, capillary loss, and capillary network irregularities in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Results: Ganglion cell layer+ (P = 0.0099) and GCL++ (P = 0.0367) were significantly thicker in DM Type 1 versus DM Type 2 in 1 central mm, after adjustment for age and DM duration. The area of foveal avascular zone was significantly larger in DM Type 1 versus controls in both SCP and DCP and in DM Type 1 versus Type 2 only in DCP (P , 0.05 for all); the number of focally dilated endings of the capillaries was higher in DM Type 1 versus controls in both SCP and DCP (P , 0.01 for all); and in DM Type 2 versus controls only in DCP (P = 0.007). Perifoveal capillary loss in SCP and inner retinal layer thickness had the highest correlation in both DM types. Conclusion: There are specific neural and microvascular modifications even before clinical signs of diabetic retinopathy in DM Types 1 and 2. Perifoveal capillary loss in the SCP is highly correlated with inner retinal layer. These data may help in characterization of patients at the preclinical stage of diabetic retinopathy

Calibration of Elekta aSi EPIDs used as transit dosimeter.

The transit in vivo dosimetry performed by the Electronic Portal Imaging Device (EPID), avoids the problem of solid-state detector positioning on the patient. Moreover, the dosimetric characterization of the recent Elekta aSi EPIDs in terms of signal stability and linearity enables these detectors adaptable for the transit in vivo dosimetry with 6, 10 and 15 MV photon beams. However, the implementation of the EPID transit dosimetry requires several measurements. Recently, the present authors have developed an in vivo dosimetry method for the 3D CRT based on correlation functions defined by the ratios between the transit signal, st (w,L), by the EPID and the phantom mid-plane dose, Dm(w,L), at the Source to Axis Distance (SAD) as a function of the phantom thickness, w, and the square field dimensions, L. When the phantom mid-plane was positioned at distance d from the SAD, the ratios st(w,L)/s't(d,w,L), were used to take into account the variation of the scattered photon contributions on the EPID as a function of, d and L. The aim of this paper was the implementation of a procedure that uses generalized correlation functions obtained by nine Elekta Precise linac beams. The procedure can be used by other Elekta Precise linacs equipped with the same aSi EPIDs assuring the stabilities of the beam output factors and the EPID signals. The calibration procedure of the aSi EPID here reported avoids measurements in solid water equivalent phantoms needed to implement the in vivo dosimetry method in the radiotherapy center. A tolerance level ranging between ±5% and ±6% (depending on the type of tumor) was estimated for the comparison between the reconstructed isocenter dose, Diso and the computed dose Diso, TPS by the treatment planning system (TPS)