Cytotoxicity Screening of Several Tomato Extracts

Jose´ Luis Guil-Guerrero,Rebeca Ramos-Bueno,Ignacio Rodríguez-García,Cristóbal López-Sánchez 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.1

The cytotoxic effects of extracts of the tomato variety “Racimo” have been evaluated through the use of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at several concentrations. Three extracts—ethanol–water, petroleum ether, and in vitro digested tomato—exhibited in vitro cytotoxicity against the proliferation of the cultured cancer cell line HT-29. The concentration that caused 50% inhibition of cancer cell growth occurred (GI50) of the different extracts for HT-29 cells was 62.5μg/mL for the petroleum ether extract and 87.0μg/mL for the digested tomato extract. For the ethanol–water extract, it was not possible to determine this parameter at the assayed extract concentrations. These results clearly indicate that after the digestion process, the less polar substances, such as carotenoids and sterols, are bioavailable as active species against cancer cells. The GI50 levels for tomato extracts are similar to those values reported for medicinal plants. The results of the MTT assay on nonmutagenic CCD-18 cells showed a lack of negative effect on cell growth, which indicates that tomato extracts act selectively on HT-29 tumor cells. ^1H-Nuclear magnetic resonance spectra confirmed the presence of known compounds with accepted cytotoxic activity against tumor lines (lycopene and β-carotene). The high cytotoxicity for HT-29 cells showed by the petroleum ether extract might be due to the simultaneous presence in the extract of both carotenoids and glyceryl esters of fatty acids. The results of this work clearly indicate the importance of carotenoid consumption on colon tumor proliferation and prevention, and also the importance of the dietary fats in carotenoid bioavailability.

Analysis of Compression and Permeability Behavior of Porous Ti6Al4V by Computed Microtomography

Luis Olmos,Didier Bouvard,Jose Luis Cabezas‑Villa,Jose Lemus‑Ruiz,Omar Jiménez,Dante Arteaga 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.3

Porous materials were developed as a good alternative to replace different bones in the human body as they improve osseointegration,tissue ingrowth and simulate the mechanical properties of human bones. Such characteristics highly depend on thepore features and volume fraction. Samples with a pore volume fraction between 16 and 60% and a pore size distribution of100–500 μm were analyzed by computed microtomography. 3D images acquisition was performed at 10 μm pixel resolution,which permitted to observe the complete sample. Features like size, shape, orientation, connectivity and pore coordinationwere determined from the 3D image analysis. Compression behavior was evaluated by interrupted compression testing and,after that, new 3D images were acquired. In order to evaluate permeability, numerical simulations of flow throughout the3D images were carried out by using Avizo® software. It was found that shape and pore size distribution was similar in allsamples, showing good distribution of the pore formers inside the matrix. Full connectivity of pores was obtained with 32%volume fraction and above, and the coordination number follows the Artz model. The pores showed a radial orientation,which induces anisotropy in the flow properties. The compression showed two different behaviors, pore closing and porecoalescence. Values of permeability match with those reported for bones as well as the anisotropy in the radial and verticaldirections. It is concluded that the sample with 60 vol% of pores could be consider to be used for bone implants.

The Effect of the Buffer Size in QoS for Multimedia and bursty Traffic: When an Upgrade Becomes a Downgrade

( Luis Sequeira ),( Julian Fernandez-navajas ),( Jose Saldana ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.9

This work presents an analysis of the buffer features of an access router, especially the size, the impact on delay and the packet loss rate. In particular, we study how these features can affect the Quality of Service (QoS) of multimedia applications when generating traffic bursts in local networks. First, we show how in a typical SME (Small and Medium Enterprise) network in which several multimedia flows (VoIP, videoconferencing and video surveillance) share access, the upgrade of the bandwidth of the internal network may cause the appearance of a significant amount of packet loss caused by buffer overflow. Secondly, the study shows that the bursty nature of the traffic in some applications traffic (video surveillance) may impair their QoS and that of other services (VoIP and videoconferencing), especially when a certain number of bursts overlap. Various tests have been developed with the aim of characterizing the problems that may appear when network capacity is increased in these scenarios. In some cases, especially when applications generating bursty traffic are present, increasing the network speed may lead to a deterioration in the quality. It has been found that the cause of this quality degradation is buffer overflow, which depends on the bandwidth relationship between the access and the internal networks. Besides, it has been necessary to describe the packet loss distribution by means of a histogram since, although most of the communications present good QoS results, a few of them have worse outcomes. Finally, in order to complete the study we present the MOS results for VoIP calculated from the delay and packet loss rate.

Long-Term Evolution of the Electrical Stimulation Levels for Cochlear Implant Patients

Jose Luis Vargas,Manuel Sainz,Cristina Roldan,Isaac Alvarez,Angel de la Torre 대한이비인후과학회 2012 Clinical and Experimental Otorhinolaryngology Vol.5 No.4

imObjectives. The stimulation levels programmed in cochlear implant systems are affected by an evolution since the first switch-on of the processor. This study was designed to evaluate the changes in stimulation levels over time and the relationship between post-implantation physiological changes and with the hearing experience provided by the continuous use of the cochlear implant. Methods. Sixty-two patients, ranging in age from 4 to 68 years at the moment of implantation participated in this study. All subjects were implanted with the 12 channels COMBI 40+ cochlear implant at San Cecilio University Hospital, Granada,Spain. Hearing loss etiology and progression characteristics varied across subjects. Results. The analyzed programming maps show that the stimulation levels suffer a fast evolution during the first weeks after the first switch-on of the processor. Then, the evolution becomes slower and the programming parameters tend to be stable at about 6 months after the first switch-on. The evolution of the stimulation levels implies an increment of the electrical dynamic range, which is increased from 15.4 to 20.7 dB and improves the intensity resolution. A significant increment of the sensitivity to acoustic stimuli is also observed. For some patients, we have also observed transitory changes in the electrode impedances associated to secretory otitis media, which cause important changes in the programming maps. Conclusion. We have studied the long-term evolution of the stimulation levels in cochlear implant patients. Our results show the importance of systematic measurements of the electrode impedances before the revision of the programming map. This report also highlights that the evolution of the programming maps is an important factor to be considered in order to determine an adequate calendar fitting of the cochlear implant processor.

Letters to the Editor : Retiform Purpura Caused by the Use of Cocaine, That Was Probably Adulterated with Levamisole

( Jose Luis Torregrosa Calatayud ),( Juan Garcias Ladaria ),( Blanca De Unamuno Bustos ),( Violeta Zaragoza Ninet ),( Victor Alegre De Miquel ) 대한피부과학회 2015 Annals of Dermatology Vol.27 No.1

남미의 경험과 한국경제 (연구조사자료36) 161~195

Jose Luis Machinea 한국경제연구원 1990 한국경제연구원 연구조사자료 Vol.YJ1990-001 No.-

Association between Heart Failure and Clinical Prognosis in Patients with Acute Ischemic Stroke: A Retrospective Cohort Study

Jose Luis Lozano Villanueva,Javier Francisco Torres Zafra,Fabián Cortés Muñoz,Fernán del Cristo Mendoza Beltrán,Jenny Carolina Sánchez Casas,Luis Alfonso Barragán Pedraza 대한신경과학회 2021 Journal of Clinical Neurology Vol.17 No.2

Background and Purpose Ischemic stroke is a common cause of death worldwide. In clinical practice it is observed that many individuals who have experienced an ischemic stroke also suffer from simultaneous comorbidities such as heart failure, which could be directly associated with a worse clinical prognosis. Therefore, this study analyzed outcomes in terms of the severity of the event, inhospital mortality, duration of hospital stay, and inhospital recurrence of the episode, in order to determine the implications resulting from the presentation of both pathologies. Methods This was a retrospective-cohort, hospital-based study. Results The study included 110 subjects with heart failure (exposed) and 109 subjects without heart failure (nonexposed). The incidence of inhospital mortality was 27.27% in exposed patients and 9.17% in nonexposed patients (p<0.001), and the presence of heart failure increased the risk of death by 92% (p=0.027). According to scores on the National Institutes of Health Stroke Scale, the median severity was worse in exposed than nonexposed patients (16.1 vs. 9.2, p=0.001). The median hospital stay was 9 days in subjects with heart failure and 7 days in nonexposed patients (p=0.011). The rate of inhospital stroke did not differ significantly between exposed and nonexposed patients (1.82% vs. 0.92%, p=0.566). Conclusions Individuals with heart failure who suffer from an acute ischemic stroke show worse clinical outcomes in terms of mortality, event severity, and duration of hospital stay.

남미의 경험과 한국경제 (연구조사자료36) 97~128

Jose Luis Machinea 한국경제연구원 1990 한국경제연구원 연구조사자료 Vol.YJ1990-001 No.-

Effect of Pectin on the Expression of Proteins Associated with Mitochondrial Biogenesis and Cell Senescence in HT29-Human Colorectal Adenocarcinoma Cells

Jose Javier Zamorano-Leon,Sandra Ballesteros,Natalia de las Heras,Luis Alvarez-Sala,Mariano de la Serna-Soto,Khaoula Zekri-Nechar,Gala Freixer,Bibiana Calvo-Rico,Zhengguang Yang,Jose Manuel Garcia-Gar 한국식품영양과학회 2019 Preventive Nutrition and Food Science Vol.24 No.2

Mitochondria dynamic is regulated by different proteins, maintaining a balance between fission and fusion. An imbalance towards mitochondrial fission has been associated with tumor cell proliferation. The aim of this study was to analyze whether pectin modifies the viability of human colon cancer cells and the expression of proteins involved in mitochondrial fusion and fission. The human colon carcinoma cell line HT29 cells was growth in 10% fetal bovine serum in the absence and presence of pectin. Pectin reduced HT29 cell viability in a concentration-dependent manner, reaching a plateau at 150∼300 μ㏖/L pectin. The presence of 200 μ㏖/L pectin reduced the expression of dynamin-related protein-1 and increased expression of the mitochondrial fusion-associated proteins mitofusin-1 and 2. Expression of cyclin B1, a protein involved in G2/M transition, was found decreased in pectin-incubated HT29 cells. Moreover, expression of p53 protein, the amount of p53 in the nucleous and β-galactosidase activity, which are all biomarkers for cellular senescence, were significantly higher in pectin-incubated HT29 cells than in HT29 cells incubated without pectin. Expression of the protein B-cell lymphoma 2 (Bcl-2) homologous antagonist/killer was increased in response to incubation with pectin. However, incubation with pectin did not affect expression of Bcl-2-associated X protein or Bcl-2, or the caspase-3 activity. Overall, we concluded that pectin reduces the viability of human HT29 colon cancer cells, which is accompanied with a shift in the expression of proteins associated with mitochondrial dynamics towards mitochondrial fusion. Moreover, incubation with pectin favors cellular senescence over apoptosis in HT29 cells.

Prediction of Non-Genotoxic Carcinogenicity Based on Genetic Profiles of Short Term Exposure Assays

Luis Orlando Perez,Rolando Gonzalez-Jose,Pilar Peral Garcia 한국독성학회 2016 Toxicological Research Vol.32 No.4

Non-genotoxic carcinogens are substances that induce tumorigenesis by non-mutagenic mechanisms and long term rodent bioassays are required to identify them. Recent studies have shown that transcription profiling can be applied to develop early identifiers for long term phenotypes. In this study, we used rat liver expression profiles from the NTP (National Toxicology Program, Research Triangle Park, USA) DrugMatrix Database to construct a gene classifier that can distinguish between non-genotoxic carcinogens and other chemicals. The model was based on short term exposure assays (3 days) and the training was limited to oxidative stressors, peroxisome proliferators and hormone modulators. Validation of the predictor was performed on independent toxicogenomic data (TG-GATEs, Toxicogenomics Project-Genomics Assisted Toxicity Evaluation System, Osaka, Japan). To build our model we performed Random Forests together with a recursive elimination algorithm (VarSelRF). Gene set enrichment analysis was employed for functional interpretation. A total of 770 microarrays comprising 96 different compounds were analyzed and a predictor of 54 genes was built. Prediction accuracy was 0.85 in the training set, 0.87 in the test set and increased with increasing concentration in the validation set: 0.6 at low dose, 0.7 at medium doses and 0.81 at high doses. Pathway analysis revealed gene prominence of cellular respiration, energy production and lipoprotein metabolism. The biggest target of toxicogenomics is accurately predict the toxicity of unknown drugs. In this analysis, we presented a classifier that can predict non-genotoxic carcinogenicity by using short term exposure assays. In this approach, dose level is critical when evaluating chemicals at early time points.