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Moran-Ramos S.,Instituto Nacional Of Ciencias Medicas | Moran-Ramos S.,National Autonomous University of Mexico | Avila-Nava A.,National Autonomous University of Mexico | Tovar A.R.,Instituto Nacional Of Ciencias Medicas | And 3 more authors.
Journal of Nutrition | Year: 2012

Nonalcoholic fatty liver disease (NAFLD) is associated with multiple factors such as obesity, insulin resistance, and oxidative stress. Nopal, a cactus plant widely consumed in the Mexican diet, is considered a functional food because of its antioxidant activity and ability to improve biomarkers of metabolic syndrome. The aim of this study was to assess the effect of nopal consumption on the development of hepatic steatosis and hepatic oxidative stress and on the regulation of genes involved in hepatic lipid metabolism. Obese Zucker (fa/fa) rats were fed a control diet or a diet containing 4% nopal for 7 wk. Rats fed the nopal-containing diet had;50% lower hepatic TG than the control group as well as a reduction in hepatomegaly and biomarkers of hepatocyte injury such as alanine and aspartate aminotransferases. Attenuation of hepatic steatosis by nopal consumption was accompanied by a higher serum concentration of adiponectin and a greater abundance of mRNA for genes involved in lipid oxidation and lipid export and production of carnitine palmitoyltransferase-1 and microsomal TG transfer proteins in liver. Hepatic reactive oxygen species and lipid peroxidation biomarkers were significantly lower in rats fed nopal compared with the control rats. Furthermore, rats fed the nopal diet had a lower postprandial serum insulin concentration and a greater liver phosphorylated protein kinase B (pAKT):AKT ratio in the postprandial state. This study suggests that nopal consumption attenuates hepatic steatosis by increasing fatty acid oxidation and VLDL synthesis, decreasing oxidative stress, and improving liver insulin signaling in obese Zucker (fa/fa) rats. © 2012 American Society for Nutrition.

Rosetti F.,Instituto Nacional Of Ciencias Medicas | Mayadas T.N.,Harvard University
Immunological Reviews | Year: 2016

Mac-1 (CD11b/CD18) is a β2 integrin classically regarded as a pro-inflammatory molecule because of its ability to promote phagocyte cytotoxic functions and enhance the function of several effector molecules such as FcγR, uPAR, and CD14. Nevertheless, recent reports have revealed that Mac-1 also plays significant immunoregulatory roles, and genetic variants in ITGAM, the gene that encodes CD11b, confer risk for the autoimmune disease systemic lupus erythematosus (SLE). This has renewed interest in the physiological roles of this integrin and raised new questions on how its seemingly opposing biological functions may be regulated. Here, we provide an overview of the CD18 integrins and how their activation may be regulated as this may shed light on how the opposing roles of Mac-1 may be elicited. We then discuss studies that exemplify Mac-1's pro-inflammatory versus regulatory roles particularly in the context of IgG immune complex-mediated inflammation. This includes a detailed examination of molecular mechanisms that could explain the risk-conferring effect of rs1143679, a single nucleotide non-synonymous Mac-1 polymorphism associated with SLE. © 2016 John Wiley & Sons A/S.

Cuevas-Ramos D.,Instituto Nacional Of Ciencias Medicas | Aguilar-Salinas C.A.,Instituto Nacional Of Ciencias Medicas | Gomez-Perez F.J.,Instituto Nacional Of Ciencias Medicas
Current Opinion in Pediatrics | Year: 2012

PURPOSE OF REVIEW: FGF21 has emerged as a hormone involved in energy homeostasis. A large number of recent reports have expanded the role of FGF21 from a response factor to prolonged fasting to a key hormone that regulates free fatty acid (FFAs) levels. The therapeutic role of recombinant human FGF21 for type 2 diabetes and dyslipidemia is under study. RECENT FINDINGS: Recent evidence suggests that supraphysiological concentrations of FFAs induce FGF21 secretion (i.e., starvation and intense physical activity) through the peroxisome proliferator-activated receptor alpha (PPARα) pathway. The rise in FGF21 levels is aimed at improving energy production (ketogenesis) and utilization (oxidation) of FFAs. FGF21 increment may protect against chronic exposure to high concentrations of FFAs, which causes lipotoxicity in muscle, pancreas, and liver. In addition, FGF21 induces appetite and inhibits growth, probably as part of the adaptive starvation response. The autocrine function of FGF21 in adipose tissue increases PPARγ activity and glucose uptake. Increased plasma FGF21 levels have been found in insulin resistance states in humans. However, the reason for this rise in FGF21 values is still under study. SUMMARY: We propose that FGF21 serves as a defense mechanism against supraphysiological concentrations of FFAs. In addition, FGF21 might have a therapeutic indication in humans. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Kimura-Hayama E.T.,Grupo Mexico | Higuera J.A.,Instituto Nacional Of Ciencias Medicas | Corona-Cedillo R.,Magnetic Resonance Unit | Chavez-Macias L.,Hospital General Of Mexico | And 4 more authors.
Radiographics | Year: 2010

Neurocysticercosis is a neurologic parasitic disease caused by the encysted larva of the tapeworm Taenia solium and is the most important parasitic disease of the human central nervous system. It is the most common cause of acquired epilepsy in endemic settings and constitutes a public health challenge for most of the developing world. Nowadays, however, as a result of globalization, neurocysticercosis is being seen more frequently in developed countries as well. Neurocysticercosis is acquired through fecal-oral contamination, and the disease course is complex, with two intermediate hosts (ie, pigs and humans) and a definitive host (humans). Traditionally, it has been classified into active and nonactive forms according to disease location. Radiologists must be aware of its imaging appearance, which is quite variable, as is the differential diagnosis. Imaging findings depend on several factors, including the stage of the life cycle of T solium at presentation; the number and location (ie, subarachnoid, cisternal, or intraventricular) of parasites; and associated complications such as vascular involvement (ie, arteritis with or without infarction), inflammatory response (ie, edema, gliosis, or arachnoiditis), and, in ventricular forms, degree of obstruction. Thus, the diagnostic approach, management, and prognosis for neurocysticercosis differ widely depending on the type of infection. © RSNA, 2010.

Jimenez-Corona A.,Instituto Nacional Of Salud Publica | Aguilar-Salinas C.A.,Instituto Nacional Of Ciencias Medicas | Rojas-Martinez R.,Instituto Nacional Of Salud Publica | Hernandez-Avila M.,Instituto Nacional Of Salud Publica
Salud Publica de Mexico | Year: 2013

Objective. To determine the frequency of application of prevention and control measures for type 2 diabetes in Mexican population. Materials and methods. ENSANUT 2012 is a nationally and by-state representative survey. Sample design was probabilistic, multistage, stratified and clustered. The information of 46 277 adults=20 was used for this analysis. A weighted analysis was performed using Stata 12. Results. Prevalence of diabetes by previous diagnosis was 9.2% (6.4 millions) in ENSANUT 2012, 7.3% (3.7 millions) in 2006 and 4.6% (2.1 millions) in 2000. In 2012, the mean of medical examinations in the previous year related to diabetes control was 7.3. However, the percentage of cases in which preventive actions for chronic complications were performed (such as foot care [14.6%], ophthalmology [8.6%] and determination of HbA1c [9.6%]) was low. Conclusions. Patients with diabetes have frequent access to medical services. However, preventive actions are applied insufficiently both in quality and quantity.

Garcia-Munoz R.,Hospital San Pedro | Llorente L.,Instituto Nacional Of Ciencias Medicas
Immunology | Year: 2014

Immunological tolerance theory in chronic lymphocytic leukaemia (CLL): we suggest that B cells that express B-cell receptors (BCR) that recognize their own BCR epitopes are viewed by immune system as 'dangerous cells'. BCR autonomous signalling may induce constant receptor editing and mistakes in allelic exclusion. The fact that whole BCR recognizes a self-antigen or foreing antigen may be irrelevant in early B cell development. In early B cells, autonomous signalling induced by recognition of the BCR's own epitopes simulates an antigen-antibody engagement. In the bone marrow this interaction is viewed as recognition of self-molecules and induces receptor editing. In mature B cells autonomous signalling by the BCR may promote 'reversible anergy' and also may correct self-reactivity induced by the somatic hypermutation mechanisms in mutated CLL B cells. However, in unmutated CLL B cells, BCR autonomous signalling in addition to self-antigen recognition augments B cell activation, proliferation and genomic instability. We suggest that CLL originates from a coordinated normal immunologic tolerance mechanism to destroy self-reactive B cells. Additional genetic damage induced by tolerance mechanisms may immortalize self-reactive B cells and transform them into a leukemia. © 2014 John Wiley & Sons Ltd.

Garcia M.P.M.,Instituto Nacional Of Ciencias Medicas
Annals of Hepatology | Year: 2011

The prevalence of under nutrition in cirrhotic patients is 61% and it usually progresses as the disease becomes more advanced. The deterioration in the nutritional status and its associated metabolic derangements has raised doubts about the benefits of severe and prolonged protein restriction as a treatment for hepatic encephalopathy. However, the practice of dietary protein restriction for patients with liver cirrhosis is deeply embedded among medical practitioners and dietitians. To date, no solid conclusions may be drawn about the benefit of protein restriction. However, the negative effects of protein restriction are clear, that is, increased protein catabolism, the release of amino acids from the muscle, and possible worsening of hepatic encephalopathy. In conclusion, chronic protein restriction causes progressive and harmful protein depletion and must be avoided.

Mink S.N.,University of Manitoba | Jacobs H.,University of Manitoba | Gotes J.,Instituto Nacional Of Ciencias Medicas | Kasian K.,University of Manitoba | Cheng Z.-Q.,University of Manitoba
Journal of Applied Physiology | Year: 2011

Although hydrogen peroxide (H2O2) is a well-described reactive oxygen species that is known for its cytotoxic effects and associated tissue injury, H2O2 has recently been established as an important signaling molecule. We previously demonstrated that lysozyme (Lzm-S), a mediator of sepsis that is released from leukocytes, could produce vasodilation in a phenylephrine-constricted carotid artery preparation by H 2O2 signaling. We found that Lzm-S could intrinsically generate H2O2 and that this generation activated H 2O2-dependent pathways. In the present study, we used this carotid artery preparation as a bioassay to define those antioxidants that could inhibit Lzm-S's vasodilatory effect. We then determined whether this antioxidant could reverse the hypotension that developed in an Escherichia coli bacteremic model. Of the many antioxidants tested, we found that ethyl gallate (EG), a nonflavonoid phenolic compound, was favorable in inhibiting Lzm-S-induced vasodilation. In our E. coli model, we found that EG reversed the hypotension that developed in this model and attenuated end-organ dysfunction. By fluorometric H2O2 assay and electrochemical probe techniques, we showed that EG could scavenge H2O2 and that it could reduce H2O2 production in model systems. These results show that EG, an antioxidant that was found to scavenge H 2O2 in vitro, was able to attenuate cardiovascular dysfunction in a canine in vivo preparation. Antioxidants such as EG may be useful in the treatment of hemodynamic deterioration in septic shock. © 2011 the American Physiological Society.

De La Garza-Villasenor L.,Instituto Nacional Of Ciencias Medicas
Cirugia y Cirujanos | Year: 2010

Background: Humans use many ways to communicate with fellow humans. Symbols have been one of these ways. Shamans probably used these in the beginning and adopted other distinctive symbols as they were introduced. Discussion: The origin, the reason and use of three symbols in medicine and surgery are discussed. Some symbols currently remain the same and others have been modified or have disappeared. The oldest of these three symbols is the staff of Aesculapius, related to the Greek god of medicine and health. Since the 19 th century, in some countries the symbol of the medical profession has become the caduceus, but the staff is the natural symbol. The second symbol is the barber pole that was created at the beginning of the Middle Ages. This was the means to locate the office and shop of a barber/surgeon in towns, cities and battlefields. On the other hand, the surgeon made use of the emblem of the union, trade or fraternity to which he belonged, accompanied by the bowl for bloodletting. The third symbol is the wearing of long and short robes that distinguished graduate surgeons from a medical school and the so-called barber/surgeons. Conclusions: Symbols facilitate the manner in which to identify the origin or trade of many working people. Some symbols currently remain and others have either been modified or are obsolete, losing their relationship with surgery and medicine.

Noyola-Martinez N.,Instituto Nacional Of Ciencias Medicas | Diaz L.,Instituto Nacional Of Ciencias Medicas | Zaga-Clavellina V.,Instituto Nacional Of Perinatologia Isidro Espinosa Of Los Reyes | Avila E.,Instituto Nacional Of Ciencias Medicas | And 3 more authors.
Journal of Steroid Biochemistry and Molecular Biology | Year: 2014

Placenta is an important source of endocrine and immunological factors. During pregnancy, calcitriol, the active metabolite of vitamin D, is also metabolized by decidua and placental tissue by means of CYP27B1 and CYP24A1 for synthesis and inactivation of calcitriol respectively. Calcitriol production is regulated by several factors in a tissue-specific manner. However, the association of pro-inflammatory cytokines on calcitriol metabolism has not been studied in human placenta. The aim of the present study was to investigate the effects of TNF-α, INF-γ, IL-6 and IL-1β upon CYP27B1 and CYP24A1 gene expression in primary cultures of human placental cells. Placentas were obtained immediately after delivery by cesarean section from normotensive women. Cytokine effects upon mRNA of CYPs in enriched trophoblastic cell preparations were evaluated by using qPCR. The results showed that incubation of trophoblasts in the presence of each cytokine resulted in a significant increase of both CYPs expression. Interestingly, TNF-α increased significantly the ratio of CYP24A1/CYP27B1 gene expression, while IFN-γ preferentially induced CYP27B1, whereas IL-1β and IL-6 stimulated gene expression of both CYPs in the same proportion. The results suggest that cytokines among other factors regulate calcitriol metabolism in human placenta; specifically, INF-γ may contribute to calcitriol production while TNF-α favors its catabolism. © 2013 Elsevier Ltd.

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