• Title/Summary/Keyword: Herrera

Search Result 46, Processing Time 0.024 seconds

Fenofibrate reduces adiposity in pregnant and virgin rats but through different mechanisms

  • Del Carmen Gonzalez, Maria;Vidal, Hubert;Herrera, Emilio;Bocos, Carlos
    • BMB Reports
    • /
    • v.42 no.10
    • /
    • pp.679-684
    • /
    • 2009
  • Fenofibrate has been proven to reduce adiposity. Since gestation produces an increase in white adipose tissue (WAT) mass, we comparatively studied this drug-effect in virgin and pregnant rats. Fenofibrate reduced lumbar WAT weight in both pregnant and virgin rats. Fenofibrate treatment did not modify plasma free fatty acid (FFA) concentration in virgin rats, it greatly increased it in pregnant animals. Remarkable differences between the two groups were obtained for two proteins related to fatty acid oxidation and esterification and storing. Respectively, the mRNA levels of carnitine palmitoyltransferase I (CPT-I) were increased by the fenofibrate only in the virgin rats and a similar finding was observed for the expression of phosphoenolpyruvate carboxykinase (PEPCK). These findings indicate that fenofibrate reduces adiposity in pregnant and virgin rats through different mechanisms: a) in virgin rats, by promoting fatty acid oxidation; and b) in pregnant rats, by enhancing fatty acid output.

Theoretical Investigation of the Triphosphate Forms of Azidothymidine and Thymidine

  • Arissawa, Marcia;Felcman, Judith;Herrera, Juan Omar Machucca
    • BMB Reports
    • /
    • v.36 no.3
    • /
    • pp.243-250
    • /
    • 2003
  • In this paper we investigate (using AM1 semi-empirical as well as HF methods at the STO-3G, 3-21G, 6-31G, 6-$31G^*$ and 6-31+$G^{**}$ level) the conformations, geometrical parameters, Mulliken charges, and solvation effects of the triphosphate form of AZT (AZTTP), as well as the thymidine nucleotide (dTTP) structure. Our calculated geometrical parameters and Mulliken charges, with and without solvation effects, are correlated with recent experimental results.

Testing and modelling of shape memory alloy plates for energy dissipators

  • Heresi, Pablo;Herrera, Ricardo A.;Moroni, Maria O.
    • Smart Structures and Systems
    • /
    • v.14 no.5
    • /
    • pp.883-900
    • /
    • 2014
  • Shape memory alloys (SMA) can dissipate energy through hysteresis cycles without significant residual deformation. This paper describes the fabrication and testing of copper-based SMA hourglass-shaped plates for use in energy dissipation devices and the development of a numerical model to reproduce the experiments. The plates were tested under cyclic flexural deformations, showing stable hysteresis cycles without strength degradation. A detailed nonlinear numerical model was developed and validated with the experimental data, using as input the constitutive relationship for the material determined from cyclic tests of material coupons under tension loading. The model adequately reproduces the experimental results. The study is focused on the exploitation of SMA in the martensite phase.

Applications of BOTDR fiber optics to the monitoring of underground structures

  • Moffat, Ricardo A.;Beltran, Juan F.;Herrera, Ricardo
    • Geomechanics and Engineering
    • /
    • v.9 no.3
    • /
    • pp.397-414
    • /
    • 2015
  • Three different applications for monitoring displacements in underground structures using a BOTDR-based distributed optical fiber strain sensing system are presented. These applications are related to the strain measurements of (1) instrumented PVC tube designed to be attached to tunnel side wall and ceiling as a sensor; (2) rock bolts for tunnels; and (3) shotcrete lining under loading. The effectiveness of using the proposed strain sensing system is evaluated by carrying out laboratory tests, in-situ measurements, and numerical simulations. The results obtained from this validation process provide confidence that the optical fiber is able to quantify strain fields under a variety of loading conditions and consequently use this information to estimate the behavior of rock mass during mining activity. As the measuring station can be located as far as 1 km of distance, these alternatives presented may increase the safety of the mine during mining process and for the personnel doing the measurements on the field.

Magnetic Tunnel Junction based non-volatile Magnetoresistive RAM

  • Tehrani, S.;Durlam, M.;Naji, P.;DeHerrera, M.;Chen, E.Y.;Slaughter, J.M.;Rizzo, N.;Engel, B.
    • Proceedings of the Korean Magnestics Society Conference
    • /
    • 2000.09a
    • /
    • pp.33-59
    • /
    • 2000
  • Demonstrated uniform MR and resistance across 6 inch wafer, Demonstrated successful integration of MTJ and CMOS, Measured address access time of 8ns and read cycle time of 18ns for 256${\times}$2 arrays at 3.0V using a single transistor and MTJ for a cell

  • PDF

Benign osteoblastoma of the mandible: a case report

  • Maria del Carmen Navas-Aparicio
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.49 no.1
    • /
    • pp.49-52
    • /
    • 2023
  • Osteoblastoma is a rare benign neoplasm formed by osteoid tissue and well-vascularized bone that occurs mainly in children and adolescents. It appears primarily in the long bones, vertebral column, and small bones of the hands and feet, and not typically in the skull and maxillary bones. The purpose of this study is to present the case of an 8-year-old girl with a diagnosis of right mandibular osteoblastoma and a review of the relevant literature. The goals of treatment were to preserve dental occlusion, masticatory function and facial symmetry while minimizing the effects on patient body image and quality of life. Osteoblastoma, although it is benign, can be aggressive, and its treatment will depend on the timing of diagnosis, size and location. Early diagnosis is essential to avoid not only radical surgery as in the case presented, but also to help minimize the risk of possible relapse and potential malignancy of a benign osteoblastoma.

Seismic performance of moment connections in steel moment frames with HSS columns

  • Nunez, Eduardo;Torres, Ronald;Herrera, Ricardo
    • Steel and Composite Structures
    • /
    • v.25 no.3
    • /
    • pp.271-286
    • /
    • 2017
  • The use of Hollow Structural Sections (HSS) provides an alternative for steel buildings in seismic zones, with the advantage over WF columns that the HSS columns have similar resistance along both axes and enhanced performance under flexure, compression and torsion with respect to other columns sections. The HSS columns have shown satisfactory performance under seismic loads, such as observed in buildings with steel moment frames in the Honshu earthquake (2011). The purpose of this research is to propose a new moment connection, EP-HSS ("End-plate to Hollow Structural Section"), using a wide flange beam and HSS column where the end plate falls outside the range of prequalification established in the ANSI/AISC 358-10 Specification, as an alternative to the traditional configuration of steel moment frames established in current codes. The connection was researched through analytical, numerical (FEM), and experimental studies. The results showed that the EP-HSS allowed the development of inelastic action on the beam only, avoiding stress concentrations in the column and developing significant energy dissipation. The experiments followed the qualification protocols established in the ANSI/AISC 341-10 Specification satisfying the required performance for highly ductile connections in seismic zones, thereby ensuring satisfactory performance under seismic actions without brittle failure mechanisms.

Role of telomere length in subtelomeric gene expression and its possible relation to cellular senescence

  • Hernandez-Caballero, E.;Herrera-Gonzalez, N.E.;Salamanca-Gomez, F.;Arenas-Aranda, D.J.
    • BMB Reports
    • /
    • v.42 no.11
    • /
    • pp.747-751
    • /
    • 2009
  • Transcriptional silencing of subtelomeric genes is associated with telomere length, which is correlated with age. Long and short telomeres in young and old people, respectively, coincide with gene repression and activation in each case. In addition, differential location of genes with respect to telomeres causes telomere position effect. There is very little evidence of the manner in which age-related telomere length affects the expression of specific human subtelomeric genes. We analyzed the relationship between telomere length and gene expression levels in fibroblasts derived from human donors at ages ranging from 0-70 years. We studied three groups of genes located between 100 and 150 kb, 200 and 250 kb, and >300 kb away from telomeres. We found that the chromatin modifier-encoding genes Eu-HMTase1, ZMYND11, and RASA3 were overexpressed in adults. Our results suggest that short telomere length-related overexpression of chromatin modifiers could underlie transcriptional changes contributing to cellular senescence.

Differential Effects of Two Widely Used Solvents, DMSO and Ethanol, on the Growth and Recovery of Trypanosoma cruzi Epimastigotes in Culture

  • Cevallos, Ana Maria;Herrera, Juliana;Lopez-Villasenor, Imelda;Hernandez, Roberto
    • Parasites, Hosts and Diseases
    • /
    • v.55 no.1
    • /
    • pp.81-84
    • /
    • 2017
  • Trypanosoma cruzi is the etiological agent of Chagas disease. Epimastigote forms of T. cruzi can be readily cultured in axenic conditions. Ethanol and dimethyl sulfoxide (DMSO) are commonly used solvents employed as vehicles for hydrophobic compounds. In order to produce a reference plot of solvent dependent growth inhibition for T. cruzi research, the growth of epimastigotes was analyzed in the presence of different concentrations of ethanol (0.1-4.0%) and DMSO (0.5-7.5%). The ability of the parasites to resume growth after removal of these solvents was also examined. As expected, both ethanol and DMSO produced a dose-dependent inhibition of cellular growth. Parasites could recover normal growth after 9 days in up to 2% ethanol or 5% DMSO. Since DMSO was better tolerated than ethanol, it is thus recommended to prefer DMSO over ethanol in the case of a similar solubility of a given compound.

Endoscopic Balloon Dilation for Treatment of Congenital Antral Web

  • Peck, Jacquelin;Khalaf, Racha;Marth, Ryan;Phen, Claudia;Sosa, Roberto;Cordero, Francisco Balsells;Wilsey, Michael
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • v.21 no.4
    • /
    • pp.351-354
    • /
    • 2018
  • Congenital antral webs are a rare but relevant cause of gastric outlet obstruction in infants and children. The condition may lead to feeding refusal, vomiting, and poor growth. Due to the relative rarity of the disease, cases of congenital antral web are frequently misdiagnosed or diagnosed with significant delay as physicians favorably pursue diagnoses of pyloric stenosis and gastric ulcer disease, which are more prevalent. We report a case of an eight-month-old female who presented with persistent non-bilious emesis, feeding difficulties, and failure to thrive and was discovered to have an antral web. The web was successfully treated with endoscopic balloon dilation, which resolved her symptoms. Two years later, the patient remains asymptomatic and is thriving with weight at the 75th percentile for her age.