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Aranguibel D Benítez S Guillen I Villarreal L Bandres D Bastidas G 《Revista de gastroenterologia de Mexico》2012,77(2):99-102
Gastric cancer is one of the main causes of death in the world. In Venezuela, gastric tumors represent 37% of all malignant tumors of the digestive system, but only 1,6% to 3,1% of these cases are lymphoepithelioma-like carcinoma. Synchronous neoplastic lesions are also rare. The clinical case presented herein, a man with two synchronous tumor lesions, is the first of its kind in this country. Despite their incipient aspect, the histologic study reported two malignant tumors of epithelial origin: well-differentiated adenocarcinoma and lymphoepithelioma-like carcinoma. 相似文献
23.
Sandra Merscher-Gomez Johanna Guzman Christopher E. Pedigo Markku Lehto Robier Aguillon-Prada Armando Mendez Mariann I. Lassenius Carol Forsblom TaeHyun Yoo Rodrigo Villarreal Dony Maiguel Kevin Johnson Ronald Goldberg Viji Nair Ann Randolph Matthias Kretzler Robert G. Nelson George W. Burke III Per-Henrik Groop Alessia Fornoni the FinnDiane Study Group 《Diabetes》2013,62(11):3817-3827
Diabetic kidney disease (DKD) remains the most common cause of end-stage kidney disease despite multifactorial intervention. We demonstrated that increased cholesterol in association with downregulation of ATP-binding cassette transporter ABCA1 occurs in normal human podocytes exposed to the sera of patients with type 1 diabetes and albuminuria (DKD+) when compared with diabetic patients with normoalbuminuria (DKD−) and similar duration of diabetes and lipid profile. Glomerular downregulation of ABCA1 was confirmed in biopsies from patients with early DKD (n = 70) when compared with normal living donors (n = 32). Induction of cholesterol efflux with cyclodextrin (CD) but not inhibition of cholesterol synthesis with simvastatin prevented podocyte injury observed in vitro after exposure to patient sera. Subcutaneous administration of CD to diabetic BTBR (black and tan, brachiuric) ob/ob mice was safe and reduced albuminuria, mesangial expansion, kidney weight, and cortical cholesterol content. This was followed by an improvement of fasting insulin, blood glucose, body weight, and glucose tolerance in vivo and improved glucose-stimulated insulin release in human islets in vitro. Our data suggest that impaired reverse cholesterol transport characterizes clinical and experimental DKD and negatively influences podocyte function. Treatment with CD is safe and effective in preserving podocyte function in vitro and in vivo and may improve the metabolic control of diabetes.Diabetic kidney disease (DKD) is responsible for nearly half of the incidents of end-stage kidney disease in the U.S. (1), yet our current understanding of the pathophysiological processes responsible for DKD has led to limited improvements in patient outcomes. Multifactorial intervention reduces the rate of progression of DKD but does not prevent end-stage kidney disease in type 1 (T1D) or type 2 diabetes (T2D) (2,3). A key factor for this translation gap is the current lack of adequate mechanistic insight into DKD in humans.The kidney glomerulus is a highly specialized structure that ensures the selective ultrafiltration of plasma so that essential proteins are retained in the blood (4). Podocytes are glomerular epithelial cells that contribute to the glomerular filtration barrier through a tight regulation of actin cytoskeleton remodeling (4). Currently, the diagnosis of DKD relies on the detection of microalbuminuria (5). However, a growing body of evidence suggests that key histological lesions precede the development of albuminuria (6,7); among them, decreased podocyte number (podocytopenia) has been described as an independent predictor of DKD progression (8–12). Although we have previously shown that podocyte insulin resistance and susceptibility to apoptosis is already present at the time of onset of microalbuminuria in experimental models of DKD, the cause of podocyte injury in early DKD remains unknown (13).We used a previously established cell-based assay in which differentiated human podocytes are exposed to 4% patient sera for 24 h (14) to identify new pathways and targets in DKD. Podocytes exposed to the sera of patients with DKD showed increased cholesterol accumulation in association with downregulation of ATP-binding cassette transporter 1 (ABCA1) expression that was independent of circulating cholesterol.ABCA1 is a major regulator of cellular cholesterol homeostasis by mediating efflux to lipid-poor apolipoprotein acceptors in the bloodstream (15). ABCA1 genetic variants are strongly associated with the risk of coronary artery disease (16). Furthermore, the capacity of patient sera to induce ABCA1-mediated cholesterol efflux in macrophages is impaired in patients with T2D and incipient or overt nephropathy (17). Excessive cholesterol accumulation has been described in glomeruli of rodent models of T1D and T2D (18–20) and may contribute to DKD development and progression. Finally, inactivating mutations of ABCA1 result in Tangier disease, which causes premature atherosclerosis and proteinuria (21).Although interventions that increase ABCA1 expression (such as liver X receptor agonists) may be beneficial in DKD, they have a relatively high incidence of adverse events (22) as well as intrinsic lipogenic effects (23). We used β-cyclodextrins, cyclic oligosaccharides consisting of seven β(1-4)-glucopyranose rings, to remove cholesterol from differentiated human podocytes in vitro and from diabetic animals in vivo. The exact mechanism by which cyclodextrins (CDs) remove cholesterol from cells is not completely understood, but the formation of cholesterol/CD inclusion complexes at the membrane surface plays an important role in this process (24).We hypothesized that 2-hydroxypropyl-β-cyclodextrin, which was recently approved by the U.S. Food and Drug Administration (FDA) for the cure of Niemann-Pick disorder (25,26), would be an effective way to sequester cholesterol and to protect podocytes from cholesterol-dependent damage in DKD in vivo and in vitro. 相似文献
24.
Castelo B. Vilanculo Mrcio J. Da Silva Milena Galdino Teixeira Jesus Avendano Villarreal 《RSC advances》2020,10(13):7691
In this work, we describe a new one-pot synthesis route of valuable linalool oxidation derivatives (i.e., 2-(5-methyl-5-vinyltetrahydrofuran-2-yl propan-2-ol) (1a)), 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol (1b) and diepoxide (1c), using a green oxidant (i.e., hydrogen peroxide) under mild conditions (i.e., room temperature). Lacunar Keggin heteropolyacid salts were the catalysts investigated in this reaction. Among them, Na7PW11O39 was the most active and selective toward oxidation products. All the catalysts were characterized by FT-IR, TG/DSC, BET, XRD analyses and potentiometric titration. The main reaction parameters were assessed. Special attention was dedicated to correlating the composition and properties of the catalysts and their activity.In this work, the catalyst Na7PW11O39 was used in a new one-pot synthesis route to oxidize linalool to valuable derivatives (i.e., vinyltetrahydrofuran, vinyltetrahydropyran, and diepoxide), using a green oxidant (H2O2) at room temperature. 相似文献
25.
Jian Yan Daniel O. Villarreal Trina Racine Jaemi S. Chu Jewell N. Walters Matthew P. Morrow Amir S. Khan Niranjan Y. Sardesai J. Joseph Kim Gary P. Kobinger David B. Weiner 《Vaccine》2014
Despite an intensive vaccine program influenza infections remain a major health problem, due to the viruses’ ability to change its envelope glycoprotein hemagglutinin (HA), through shift and drift, permitting influenza to escape protection induced by current vaccines or natural immunity. Recently a new variant, H7N9, has emerged in China causing global concern. First, there have been more than 130 laboratory-confirmed human infections resulting in an alarmingly high death rate (32.3%). Second, genetic changes found in H7N9 appear to be associated with enabling avian influenza viruses to spread more effectively in mammals, thus transmitting infections on a larger scale. Currently, no vaccines or drugs are effectively able to target H7N9. Here, we report the rapid development of a synthetic consensus DNA vaccine (pH7HA) to elicit potent protective immunity against the H7N9 viruses. We show that pH7HA induces broad antibody responses that bind to divergent HAs from multiple new members of the H7N9 family. These antibody responses result in high-titer HAI against H7N9. Simultaneously, this vaccine induces potent polyfunctional effector CD4 and CD8T cell memory responses. Animals vaccinated with pH7HA are completely protected from H7N9 virus infection and any morbidity associated with lethal challenge. This study establishes that this synthetic consensus DNA vaccine represents a new tool for targeting emerging infection, and more importantly, its design, testing and development into seed stock for vaccine production in a few days in the pandemic setting has significant implications for the rapid deployment of vaccines protecting against emerging infectious diseases. 相似文献
26.
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28.
L.A. Soria P.M. Corva A. Branda Sica E.L. Villarreal L.M. Melucci C.A. Mezzadra J. Papaleo Mazzucco G. Fernndez Macedo C. Silvestro A. Schor M.C. Miquel 《Molecular and cellular probes》2009,23(6):304-308
The PPARGC1A gene (peroxysome proliferator-activated receptor-γ coactivator 1α gene) controls muscle fiber type and brown adipocyte differentiation; therefore, it is a candidate gene for beef quality traits (tenderness and fat content). Two SNPs (Single Nucleotide Polymorphisms) were identified within exon 8 by multiple alignment of DNA sequences obtained from 24 bulls: a transition G/A (SNP 1181) and a transversion A/T (SNP 1299). The SNP 1181 is a novel SNP, corresponding to a non-conservative substitution (AGT/AAT) that could be the cause of amino acid substitution (364Serine/364Asparagine). A Mismatch PCR method was designed to determine genotypes of 73 bulls and 268 steers for SNP 1181. Growth, slaughter and meat quality information were available for the group of steers. Allele A of SNP 1181 was not found in Angus. In 243 steers, no significant differences (P > 0.05) were found for either final live body weight, gain in backfat thickness in Spring, kidney fat weight, kidney fat percentage, Warner–Bratzler shear force at 7 days postmortem, intramuscular fat percentage or meat colour between genotype GG and AG. This SNP could be included in breed composition and population admixture analyses because there are marked differences in allelic frequencies between Bos taurus and Bos indicus breeds. 相似文献
29.
Villarreal MG Ohlsson J Abrahamsson M Sjöstrom A Sjöstrand J 《Acta ophthalmologica Scandinavica》2000,78(2):177-181
PURPOSE: 1045 children between 12 and 13 years old were examined in a field study in the G?teborg area (Sweden). The aim of this study was to report the prevalence of refractive errors, with special attention to myopia, since there are no previous reports in Sweden about this age group. METHODS: The examination included visual acuity testing and refraction under cycloplegia. RESULTS: We found a prevalence of myopia (> or = -0.5D) of 49.7% and a prevalence of bilateral myopia of 39%. In the whole population, 23.3% were considered to need glasses (> or = -0.75D). We also found a prevalence of high myopia (> or = -5D) in 2.5% of the children. DISCUSSION: No statistically significant difference in myopia with respect to gender was found. The proportion of children needing glasses is considered the best indicator of the prevalence of myopia in this sample. The results confirm that this tendency towards myopisation in a teenage population in G?teborg is similar to the prevalence found in other parts of the world. 相似文献
30.
Health interventions for the metal working industry: which is the most cost-effective? A study from a developing country 总被引:1,自引:0,他引:1
Salinas AM Villarreal E Nuñez GM Garza ME Briones H Navarro O 《Occupational medicine (Oxford, England)》2002,52(3):129-135
This study ranked the cost-effectiveness of health interventions in the metal working industry in a developing country. Data were based on 82 034 workers of the Northern region of Mexico. Effectiveness was measured through 'healthy life years' (HeaLYs) gained. Costs were estimated per worker according to type and appropriate inputs from selected health interventions. 'Hand' was the anatomical region that yielded the most gain of HeaLYs and amputation was the injury that yielded the most gain of HeaLYs. The most effective health intervention corresponded to training, followed by medical care, education, helmets, safety shoes, lumbar supports, safety goggles, gloves and safety aprons. In dollar terms, education presented the best cost-effectiveness ratio (US$637) and safety aprons presented the worst cost-effectiveness ratio (US$1 147 770). Training proved to be a very expensive intervention, but presented the best effectiveness outcome and the second best cost-effectiveness ratio (US$2084). Cost-effectiveness analyses in developing countries are critical. Corporations might not have the same funds and technology as those in developed countries or multinational companies. 相似文献