Radiocarbon age inversions and progression: Source and causes in Late Holocene sediments from Lake Chapala, western Mexico

Abstract

Objective: To investigate the effects of raloxifene on the insulin sensitivity and lipid profile in insulin-sensitive and insulin-resistant postmenopausal women. Study design: This placebo-controlled, double-blind, randomized study involved 64 postmenopausal women aged between 45 and 55 years. All subjects were screened with the insulin resistance homeostasis model assessment (IR-HOMA) and those patients in the lowest quartile (n = 16) were assigned as insulin sensitive and those in the highest quartile as insulin resistant (n = 16). Patients in both groups received either raloxifene hydrochloride (60 mg/day) or a placebo for a period of 12 weeks. Insulin sensitivity, the serum lipid profile and anthropometric measurements were established before and after therapy. Results: Women with the highest IR-HOMA scores were associated with a significantly higher weight, body mass index, waist and waist-to-hip ratio (p < 0.05). Raloxifene significantly reduced the IR-HOMA scores from 5.76 ± 2.91 to 1.93 ± 0.96 (p = 0.02) and modified the lipid profile in insulin-resistant patients when compared with the placebo group and those patients receiving raloxifene in the insulin-sensitive group. Conclusion: Raloxifene reduced insulin resistance and modified the lipid profile in insulin-resistant postmenopausal women. " 2013 Informa UK Ltd.",,,,,,"10.3109/09513590.2013.788628",,,"http://hdl.handle.net/20.500.12104/44047","http://www.scopus.com/inward/record.url?eid=2-s2.0-84879321401&partnerID=40&md5=a681916948a479c295af6caa196b3c02",,,,,,"7",,"Gynecological Endocrinology",,"674

677",,"29",,"Scopus

WOS",,,,,,"Insulin resistant; Lipid profile; Postmenopausal women",,,,,,"Raloxifene modifies the insulin sensitivity and lipid profile of postmenopausal insulin resistant women",,"Article" "45815","123456789/35008",,"Rodríguez-Noriega, E., Infectious Diseases Division, Universidad de Guadalajara, Complejo Médico, Hospital Civil de Guadalajara, Jalisco, Mexico.; Andrade-Villanueva, J., Infectious Diseases Division, Universidad de Guadalajara, Complejo Médico, Hospital Civil de Guadalajara, Jalisco, Mexico.; Amaya-Tapia, G., Infectious Diseases Division, Universidad de Guadalajara, Complejo Médico, Hospital Civil de Guadalajara, Jalisco, Mexico.",,"Rodriguez-Noriega, E.

Andrade-Villanueva, J.

Amaya-Tapia, G.",,"1989",,"Infections caused by Salmonella typhi are commonly followed by a chronic carrier state despite positive clinical and initial bacteriologic responses. The use of primary antibiotics like chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole has several major drawbacks, including in some instances the failure to prevent the carrier state. The appearance worldwide of strains with multiple resistance to the most commonly used regimens has prompted the search for new forms of therapy. Among the agents studied have been third-generation cephalosporins and quinolones, which are active in vitro against bacterial enteropathogens like S. typhi. Resolution of chronic carriage of S. typhi and other salmonellae is difficult, and regimens commonly fail (including those that combine antibiotic administration with removal of the gallbladder). In addition to being active in vitro against Salmonella species, the newer quinolones adequately penetrate the intestinal lumen, liver, bile, and gallbladder. Initial experience with norfloxacin and ciprofloxacin in oral treatment of the chronic S. typhi carrier state in adults has been promising.",,,,,,,,,"http://hdl.handle.net/20.500.12104/44036","http://www.scopus.com/inward/record.url?eid=2-s2.0-0001409114&partnerID=40&md5=d4a35cff2048bed3a75f760433ecf97d

http://ovidsp.ovid.com/ovidweb.cgi?T=JS&CSC=Y&NEWS=N&PAGE=fulltext&D=med3&AN=2672248",,,,,,,,"Reviews of Infectious Diseases",,"S1179

1187",,"11 Suppl 5",,"Scopus

MEDLINE

WOS",,,,"Index Medicus;4-Quinolones;Anti-Bacterial Agents/tu [Therapeutic Use];Anti-Infective Agents/tu [Therapeutic Use];Carrier State/dt [Drug Therapy];Humans;Salmonella Infections/dt [Drug Therapy]",,,,,,,,"Quinolones in the treatment of Salmonella carriers.",,"Review" "45823","123456789/35008",,"Zárate-del-Valle, P.F., Departamento de Química, Universidad de Guadalajara, Blvd. M. García Barragan 1421, Col. Olimpica, 44430 Guadalajara, Jalisco, Mexico; Ramírez-Sánchez, H.U., Departamento de Física, Universidad de Guadalajara, Av. Vallarta 2606, 44130 Guadalajara, Jalisco, Mexico; Fernex, F., UMR-CNRS Géosciences de l'Environnement, G•ochimie Isotopique, University de Nice, Valrose, 06108 Nice Cedex 2, France; Simoneit, B.R.T., COGER, King Saud University, Riyadh 11451, Saudi Arabia, Department of Chemistry, Oregon State University, Corvallis, OR 97331, United States; Israde-Alcantara, I., Departamento de Geología y Mineralogía, Instituto de Investigaciones Metalérgicas, Edif. U Ciudad Universitaria, 58060 Morelia, Michoacán, Mexico",,"Zarate-del-Valle, P.F.

Ramirez-Sanchez, H.U.

Fernex, F.

Simoneit, B.R.T.

Israde-Alcantara, I.",,"2011",,"The results of eight radiocarbon datings of Lake Chapala sediments (site T46) are presented, the age inversions (AI) observed and their age progression discussed. As deduced from some AIs and the 210Pb activity (site CHP4), the bioturbation zone in the lake varies over a depth of 5-25 cm. The linear sedimentation rates (LSRs) calculated from 14C ages do not match the LSR calculated from unsupported 210Pb activity for the upper sediments. This demonstrates the usefulness of dating sediments with complementary radiometric techniques such as short-lived isotope counting (SLIC), i. e., 210Pb and 137Cs. This approach leads to the following conclusions: (1) The incorporation of detrital particles with ancient carbon into the sedimentary column of the lake occurred by a combination of: (a) the presence of outcrops of hydrothermal petroleum with ages &gt;40 ka (ka = thousands of years) in the lake, and (b) mass transport due to the presence of two elongated gyre circulation patterns integrated by cyclonic circulation (counterclockwise) in the north portion of the lake and anticyclonic circulation in the southern part. (2) Consequently, the 14C ages of shallow lake sediments have geologic ages one order of magnitude greater compared to their ages determined by the 210Pb method. (3) A bioturbation mechanism is not necessary to explain the 14C AI in the top 70 cm and from 110 to 150 cm depth of the sediments. (4) According to the biological proxies data for the last 600 years B. P., the paleoclimate at Lake Chapala has changed from sub-humid to dry environmental conditions, and eutrophication has increased over the past 100 years due to local input from ongoing agricultural activities. " 2010 Springer-Verlag.