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101.
Carolina de Mattos Duarte Hugo Verli Joo Xavier de Araújo-Júnior Isac Almeida de Medeiros Eliezer J. Barreiro Carlos Alberto Manssour Fraga 《European journal of pharmaceutical sciences》2004,23(4-5):363-369
We describe herein the structural optimization of new piperamide analogues, designed from two natural prototypes, piperine 1 and piperdardine 2, obtained from Piper tuberculatum Jacq. (Piperaceae). Molecular modeling studies using semiempirical AM1 method were made in order to establish rational modifications to optimize them by molecular simplification. The targeted compounds (10) and (11) were respectively obtained using benzaldehyde (12) and para-anisaldehyde (13) as starting materials. 1H NMR spectra showed that the target compounds were diastereoselectively obtained as the (E)-isomer, the same geometry of the natural prototypes. These new synthetic amides presented significant hypotensive effects in cardiovascular essays using in vivo methodologies. Compound 11 (N-[5-(4′-methoxyphenyl)-2(E)-pentenoyl]thiomorpholine) showed a potency 10,000 times greater than its prototype 5, evidencing an optimization of the molecular architecture for this class of hypotensive drug candidates. 相似文献
102.
Significance of High Density Lipoprotein-Cholesterol in Cardiovascular Risk Prevention 总被引:2,自引:0,他引:2
Juan F. Ascaso Arturo Fernández-Cruz Pedro González Santos Antonio Hernández Mijares Alipio Mangas Rojas Prof. Jesus Millán Luis Felipe Pallardo Juan Pedro-Botet Francisco Pérez-Jiménez Gonzalo Pía Xavier Pintó Ignacio Plaza Juan Rubiés-Prat 《Am J Cardiovasc Drugs》2004,4(5):299-314
In the approach to lipid-related risk factors for cardiovascular diseases, serum high density lipoprotein-cholesterol (HDL-C) levels bear a particular significance as this lipoprotein is considered to be an antiatherogenic factor mainly, but not only, because of its influence and impact on reverse cholesterol transport. Hence the need and requirement to consider serum HDL-C levels for both primary and secondary prevention of cardiovascular disease. A particularly important aspect is the association of the 'low HDL syndrome' with the metabolic syndrome. These factors force us to consider serum HDL-C level as a therapeutic target by itself, or even in association with low density lipoprotein-cholesterol (LDL-C) levels when the latter are increased. This review stresses the aspects connecting serum HDL-C levels and cardiovascular risk, and looks at the populations that should be considered amenable to therapeutic management because of low serum HDL-C levels. We review therapeutic strategies, both pharmacological and nonpharmacological. The aim of this review is to present therapeutic management recommendations for correcting the proportion of cardiovascular risk that is attributable to changes in HDL-C. Serum HDL-C levels of >40 mg/dL must be a therapeutic target in primary and secondary prevention. This goal is particularly important in patients with low serum HDL-C levels and ischemic heart disease (IHD) or its equivalents, even if the therapeutic target for serum LDL-C levels (<100 mg/dL) has been achieved. The first choice for this clinical condition is fibric acid derivates. The same therapeutic option should be considered in patients without IHD with low serum HDL-C levels and high cardiovascular risk (>20%), hypertriglyceridemia, type 2 diabetes mellitus, or metabolic syndrome. 相似文献
103.
104.
Evelina Chapman Ludovic Reveiz Amy Chambliss Stephanie Sangalang Xavier Bonfill 《Journal of clinical epidemiology》2013,66(1):105-112
ObjectivesTo use an “evidence-mapping” approach to assess the usefulness of Cochrane reviews in identifying research gaps in the maternal health.Study Design and SettingThe article describes the general mapping, prioritizing, reconciling, and updating approach: (1) identifying gaps in the maternal health research using published systematic reviews and formulating research questions, (2) prioritizing questions using Delphi method, (3) reconciling identified research priorities with the existing literature (i.e., searching of ongoing trials in trials registries), (4) updating the process. A comprehensive search of Cochrane systematic reviews published or updated from January 2006 to March 2011 was performed. We evaluated the “Implications for Research” section to identify gaps in the research.ResultsOur search strategy identified 695 references; 178 systematic reviews identifying at least one research gap were used. We formulated 319 research questions, which were classified into 11 different categories based on the direct and indirect causes of maternal mortality: postpartum hemorrhage, abortion, hypertensive disorders, infection/sepsis, caesarean section, diabetes, pregnancy prevention, preterm labor, other direct causes, indirect causes, and health policies and systems. Most research questions concerned the effectiveness of clinical interventions, including drugs (42.6%), nonpharmacologic interventions (16.3%), and health system (14.7%).ConclusionIt is possible to identify gaps in the maternal health research by using this approach. 相似文献
105.
106.
107.
David E. Barroso Terezinha M.P.P. Casti?eiras Fernanda S. Freitas Jane W. Marsh Mary G. Krauland Mary M. Tulenko érica L. Fonseca Ana C.P. Vicente Maria C. Rebelo Elaine O. Cerqueira Adriano C. Xavier Ana P.C.M. Cardozo Simone E.M. da Silva Lee H. Harrison 《Emerging infectious diseases》2013,19(11):1847-1850
During 2003–2012, 8 clusters of meningococcal disease were identified in Rio de Janeiro State, Brazil, all caused by serogroup C Neisseria meningitidis. The isolates were assigned to 3 clonal complexes (cc): cc11, cc32, and cc103. These hyperinvasive disease lineages were associated with endemic disease, outbreaks, and high case-fatality rates. 相似文献
108.
T.C.A. Ferrari M.A.P. Xavier P.V.T. Vidigal N.S. Amaral P.A. Diniz A.P. Resende D.M. Miranda A.C. Faria A.S. Lima L.C. Faria 《Brazilian journal of medical and biological research》2014,47(11):990-994
Estimates of occult hepatitis B virus (HBV) infection prevalence varies among
different studies depending on the prevalence of HBV infection in the study
population and on the sensitivity of the assay used to detect HBV DNA. We
investigated the prevalence of occult HBV infection in cirrhotic patients undergoing
liver transplantation in a Brazilian referral center. Frozen liver samples from 68
adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. The
specificity of the amplified HBV sequences was confirmed by direct sequencing of the
amplicons. The patient population comprised 49 (72.1%) males and 19 (27.9%) females
with a median age of 53 years (range=18-67 years). Occult HBV infection was diagnosed
in three (4.4%) patients. The etiologies of the underlying chronic liver disease in
these cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of the
patients with cryptic HBV infection also presented hepatocellular carcinoma. Markers
of previous HBV infection were available in two patients with occult HBV infection
and were negative in both. In conclusion, using a sensitive nested polymerase chain
reaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence of
occult HBV infection in cirrhotic patients undergoing liver transplant, probably due
to the low prevalence of HBV infection in our population. 相似文献
109.