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2-Aminobenzothiazoles Inhibit Virulence Gene Expression and Block Polymyxin Resistance in Salmonella enterica. Chembiochem 2020; 21:3500-3503. [PMID: 32750193 DOI: 10.1002/cbic.202000422] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/30/2020] [Indexed: 01/01/2023]
Abstract
One promising strategy to combat antibiotic-resistant bacteria is to develop compounds that block bacterial defenses against antibacterial conditions produced by the innate immune system. Salmonella enterica, which causes food-borne gastroenteritis and typhoid fever, requires histidine kinases (HKs) to resist innate immune defenses such as cationic antimicrobial peptides (CAMPs). Herein, we report that 2-aminobenzothiazoles block histidine kinase-dependent phenotypes in Salmonella enterica serotype Typhimurium. We found that 2-aminobenzothiazoles inhibited growth under low Mg2+ , a stressful condition that requires histidine kinase-mediated responses, and decreased expression of the virulence genes pagC and pagK. Furthermore, we discovered that 2-aminobenzothiazoles weaken Salmonella's resistance to polymyxin B and polymyxin E, which are last-line antibiotics and models for host defense CAMPs. These findings raise the possibilities that 2-aminobenzothiazoles can block HK-mediated bacterial defenses and can be used in combination with polymyxins to treat infections caused by Salmonella.
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A Call for Better Integrated Policies to Accelerate the Fertility Decline in Sub-Saharan Africa. Stud Fam Plann 2020; 51:193-204. [PMID: 32538513 DOI: 10.1111/sifp.12118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
To accelerate their demographic transition, sub-Saharan African (SSA) countries must trigger significant and rapid fertility declines. These fertility declines will open a demographic window of opportunity and enable countries to capture a first demographic dividend. Despite some successes, many programs aimed at decreasing fertility in SSA have yielded disappointing results. This commentary argues that better integrated policies will help to accelerate fertility declines in SSA. Such an approach should harness the synergies between a set of four key policy levers: women's empowerment; female education; family planning, reproductive health services, and universal health coverage; and legal reforms. These policy levers should be coupled with renewed commitment from leaders on the continent and increased investments in both family planning and population institutions. By concomitantly investing in these priorities and harnessing the synergies of these policy levers, countries in SSA have a critical opportunity to accelerate their demographic transition, which could help them reach emerging economy status.
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3
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Exploring the copper resistance mechanism of the lipoprotein DcrB in
Salmonella enterica. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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4
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Discovery of small molecules that sensitize
Salmonella
to polymyxin antibiotics. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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5
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Structural and Functional Characterization of Fumarase C from
Salmonella enterica. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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6
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Closed fumarase C active‐site structures reveal SS Loop residue contribution in catalysis. FEBS Lett 2019; 594:337-357. [DOI: 10.1002/1873-3468.13603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/26/2019] [Accepted: 09/05/2019] [Indexed: 12/23/2022]
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The structure of DcrB, a lipoprotein from Salmonella enterica, reveals flexibility in the N-terminal segment of the Mog1p/PsbP-like fold. J Struct Biol 2018; 204:513-518. [PMID: 30339832 PMCID: PMC9976613 DOI: 10.1016/j.jsb.2018.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/08/2018] [Accepted: 10/15/2018] [Indexed: 01/01/2023]
Abstract
DcrB is an 18 kDa lipoprotein that contains a single domain of unknown function. DcrB is found within Enterobacteriaceae, a family of Gram-negative bacteria which includes pathogens that can cause food-borne illness and hospital-acquired infections. In Salmonella enterica serovar Typhimurium, DcrB is up-regulated by conditions that promote the production of known virulence factors. We determined the structure of a truncated form of DcrB from Salmonella to 1.92 Å resolution by X-ray crystallography. This truncated form, DcrBΔ37, contains the entire domain of unknown function but lacks the lipoprotein signal sequence (residues 1-20) as well as residues 21-37. The DcrBΔ37 monomer contains the Mog1p/PsbP-like fold, which is found in functionally diverse proteins in mammals, yeast, plants, and cyanobacteria. Interestingly, DcrBΔ37 crystallized as a domain-swapped homodimer in which the N-terminal β-hairpin extends from one protomer to interact with the core of the second protomer. This domain-swapping indicates that the N-terminal portion of the Mog1p/PsbP-like fold likely has conformational flexibility. Overall, our results provide the first example of an enterobacterial protein that contains the Mog1p/PsbP-like fold and expands knowledge of the structural and phylogenetic diversity of Mog1p/PsbP-like proteins.
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Continuity and Change in Sub-Saharan African Demography. Population Studies 2015. [DOI: 10.1080/00324728.2015.1064605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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10
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Population and climate change: who will the grand convergence leave behind? THE LANCET GLOBAL HEALTH 2014; 2:e253-4. [DOI: 10.1016/s2214-109x(14)70021-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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Abstract
Like many other countries worldwide, Africa faces a rapidly increasing elderly population; however, most African countries also still have very high levels of fertility, high rates of population growth, and very young populations. This means African countries will have to address the doubling or even the tripling, by 2050, of their working-age population and better prepare for the future of their upcoming young generations, while aiming for a “modern” demographic regime of low mortality and low fertility. Such a regime would put African countries in a position to capture a demographic dividend, realize inclusive growth, reduce poverty levels, and achieve economic convergence. Socioeconomic advances help foster demographic transformations, and improvements in demographic indicators also help trigger socioeconomic advances, but this process is not automatic. Authorities will need to intervene swiftly on mortality, and particularly on fertility, through adequate population and health policies and programs.
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12
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The State and the Stork: The Population Debate and Policy Making in US History. Population Studies 2013. [DOI: 10.1080/00324728.2013.844952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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13
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Abstract
Nematodes represent a diverse phylum of both free living and parasitic species. While the species Caenorhabditis elegans is a valuable model organism, parasitic nematodes or helminths pose a serious threat to human health. Indeed, helminths cause many neglected tropical diseases that afflict humans. Nematode glycoconjugates have been implicated in evasive immunomodulation, a hallmark of nematode infections. One monosaccharide residue present in the glycoconjugates of several human pathogens is galactofuranose (Galf). This five-membered ring isomer of galactose has not been detected in mammals, making Galf metabolic enzymes attractive therapeutic targets. The only known pathway for biosynthetic incorporation of Galf into glycoconjugates depends upon generation of the glycosyl donor UDP-Galf by the flavoenzyme uridine 5'-diphosphate (UDP) galactopyranose mutase (UGM or Glf). A putative UGM encoding gene (glf-1) was recently identified in C. elegans. We sought to assess the catalytic activity of the corresponding gene product (CeUGM). CeUGM catalyzes the isomerization of UDP-Galf and UDP-galactopyranose (UDP-Galp). In the presence of enzyme, substrate, and a hydride source, a galactose-N5-FAD adduct was isolated, suggesting the CeUGM flavin adenine dinucleotide (FAD) cofactor serves as a nucleophile in covalent catalysis. Homology modeling and protein variants indicate that CeUGM possesses an active site similar to that of prokaryotic enzymes, despite the low sequence identity (∼15%) between eukaryotic and prokaryotic UGM proteins. Even with the primary sequence differences, heterocyclic UGM inhibitors developed against prokaryotic proteins also inhibit CeUGM activity. We postulate that inhibitors of CeUGM can serve as chemical probes of Galf in nematodes and as anthelmintic leads. The available data suggest that CeUGM facilitates the biosynthetic incorporation of Galf into nematode glycoconjugates through generation of the glycosyl donor UDP-Galf.
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14
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Conflicting roles for a cell surface modification in Salmonella. Mol Microbiol 2013; 88:970-83. [PMID: 23646936 DOI: 10.1111/mmi.12236] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2013] [Indexed: 12/15/2022]
Abstract
Chemical modifications of components of the bacterial cell envelope can enhance resistance to antimicrobial agents. Why then are such modifications produced only under specific conditions? Here, we address this question by examining the role of regulated variations in O-antigen length in the lipopolysaccharide (LPS), a glycolipid that forms most of the outer leaflet of the outer membrane in Gram-negative bacteria. We determined that activation of the PmrA/PmrB two-component system, which is the major regulator of LPS alterations in Salmonella enterica serovar Typhimurium, impaired growth of Salmonella in bile. This growth defect required the PmrA-activated gene wzz(st), which encodes the protein that determines long O-antigen chain length and confers resistance to complement-mediated killing. By contrast, this growth defect did not require the wzz(fepE) gene, which controls production of very long O-antigen, or other PmrA-activated genes that mediate modifications of lipid A or core regions of the LPS. Additionally, we establish that long O-antigen inhibits growth in bile only in the presence of enterobacterial common antigen, an outer-membrane glycolipid that contributes to bile resistance. Our results suggest that Salmonella regulates the proportion of long O-antigen in its LPS to respond to the different conditions it faces during infection.
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A processive carbohydrate polymerase that mediates bifunctional catalysis using a single active site. Biochemistry 2012; 51:1148-59. [PMID: 22217153 DOI: 10.1021/bi201820p] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Even in the absence of a template, glycosyltransferases can catalyze the synthesis of carbohydrate polymers of specific sequence. The paradigm has been that one enzyme catalyzes the formation of one type of glycosidic linkage, yet certain glycosyltransferases generate polysaccharide sequences composed of two distinct linkage types. In principle, bifunctional glycosyltransferases can possess separate active sites for each catalytic activity or one active site with dual activities. We encountered the fundamental question of one or two distinct active sites in our investigation of the galactosyltransferase GlfT2. GlfT2 catalyzes the formation of mycobacterial galactan, a critical cell-wall polymer composed of galactofuranose residues connected with alternating, regioisomeric linkages. We found that GlfT2 mediates galactan polymerization using only one active site that manifests dual regioselectivity. Structural modeling of the bifunctional glycosyltransferases hyaluronan synthase and cellulose synthase suggests that these enzymes also generate multiple glycosidic linkages using a single active site. These results highlight the versatility of glycosyltransferases for generating polysaccharides of specific sequence. We postulate that a hallmark of processive elongation of a carbohydrate polymer by a bifunctional enzyme is that one active site can give rise to two separate types of glycosidic bonds.
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Book reviews. Population Studies 2010. [DOI: 10.1080/00324728.2010.512432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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17
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18
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The polymerase activity of a mycobacterial galactofuranosyltransferase suggests a novel mechanism for template‐independent processive polymerization. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.1059.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Chemical probes of UDP-galactopyranose mutase. ACTA ACUST UNITED AC 2006; 13:825-37. [PMID: 16931332 DOI: 10.1016/j.chembiol.2006.06.007] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 06/05/2006] [Accepted: 06/06/2006] [Indexed: 12/26/2022]
Abstract
Many pathogenic prokaryotes and eukaryotes possess the machinery required to assemble galactofuranose (Galf)-containing glycoconjugates; these glycoconjugates can be critical for virulence or viability. Accordingly, compounds that block Galf incorporation may serve as therapeutic leads or as probes of the function of Galf-containing glycoconjugates. The enzyme UDP-galactopyranose mutase (UGM) is the only known generator of UDP-galactofuranose, the precursor to Galf residues. We previously employed a high-throughput fluorescence polarization assay to investigate the Klebsiella pneumoniae UGM. We demonstrate the generality of this assay by extending it to UGM from Mycobacterium tuberculosis. To identify factors influencing binding, we synthesized a directed library containing a 5-arylidene-2-thioxo-4-thiazolidinone core, a structure possessing features common to ligands for both homologs. Our studies offer a blueprint for identifying inhibitors of the growing family of UGM homologs and provide insight into UGM inhibition.
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Methyl scanning: total synthesis of demethylasterriquinone B1 and derivatives for identification of sites of interaction with and isolation of its receptor(s). J Am Chem Soc 2005; 127:4609-24. [PMID: 15796526 DOI: 10.1021/ja044325h] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The principle of methyl scanning is proposed for determination of the sites of interaction between biologically active small molecules and their macromolecular target(s). It involves the systematic preparation of a family of methylated derivatives of a compound and their biological testing. As a functional assay, the method can identify the regions of a molecule that are important (and unimportant) for biological activity against even unknown targets, and thus provides an excellent complement to structural biology. Methyl scanning was applied to demethylasterriquinone B1, a small-molecule mimetic of insulin. A new, optimal total synthesis of this natural product was developed that enables the family of methyl scan derivatives to be concisely prepared for evaluation in a cellular assay. The results of this experiment were used to design a biotin-demethylasterriquinone conjugate for use as an affinity reagent. This compound was prepared in tens of milligram quantities in a four-step synthesis.
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Circulating monocytes in patients with acute coronary syndromes lack sufficient interleukin-10 production after lipopolysaccharide stimulation. Clin Exp Immunol 2004; 138:364-8. [PMID: 15498050 PMCID: PMC1809199 DOI: 10.1111/j.1365-2249.2004.02602.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Acute coronary syndromes (ACS) are associated with inflammation resulting from monocyte activation. We sought for differences in the production of pro- and anti-inflammatory cytokines by monocytes from patients with ACS. C-reactive protein (CRP) and neopterin were measured in 22 patients with acute coronary syndromes, 50 patients with stable vascular disease and 22 healthy controls. Production of tumour necrosis factor (TNF)-alpha and interleukin (IL)-10 was determined after, respectively, 6 and 24 h of incubation of full blood with lipopolysaccharide (LPS). Levels of CRP [median, interquartile range (IQR)][1.5 mg/l (0.8-4.5) ACS patient versus 2.1 (0.9-3.6) stable disease versus 0.4 (0.3-1.2) healthy controls] (P < 0.001) and neopterin [7.4 nmol/l (6.0-8.7) ACS patient versus 7.1(6.0-8.9) stable disease versus 6.4 (5.6-7.3) healthy controls] (P = 0.07) were higher in both the patient groups. IL-10 production after LPS stimulation was greatly reduced in patients with acute coronary syndromes (16 175 pg/ml, 7559-28 470 pg/ml) as opposed to patients with stable disease (28 379 pg/ml, 12 601-73 968 pg/ml) and healthy controls (63 830 pg/ml, 22 040-168 000 pg/ml) (P = 0.003). TNF-alpha production was not signi fi cantly different between the groups [7313 pg/ml (4740-12 615) ACS patient versus 11 002 (5913-14 190) stable disease versus 8229 (5225-11 364) healthy controls] (P = 0.24). Circulating monocytes in unstable coronary syndromes produce equal amounts of TNF-alpha but less IL-10 after stimulation with LPS in vitro as compared with healthy controls. We hypothesize that, in acute coronary syndromes, the production proinflammatory cytokines is not counterbalanced by anti-inflammatory cytokines such as IL-10.
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Increased alpha-linolenic acid intake lowers C-reactive protein, but has no effect on markers of atherosclerosis. Eur J Clin Nutr 2004; 58:1083-9. [PMID: 15220952 DOI: 10.1038/sj.ejcn.1601938] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE To investigate the effects of increased alpha-linolenic acid (ALA)-intake on intima-media thickness (IMT), oxidized low-density lipoprotein (LDL) antibodies, soluble intercellular adhesion molecule-1 (sICAM-1), C-reactive protein (CRP), and interleukins 6 and 10. DESIGN Randomized double-blind placebo-controlled trial. SUBJECTS Moderately hypercholesterolaemic men and women (55 +/- 10 y) with two other cardiovascular risk factors (n = 103). INTERVENTION Participants were assigned to a margarine enriched with ALA (fatty acid composition 46% LA, 15% ALA) or linoleic acid (LA) (58% LA, 0.3% ALA) for 2 y. RESULTS Dietary ALA intake was 2.3 en% among ALA users, and 0.4 en% among LA users. The 2-y progression rate of the mean carotid IMT (ALA and LA: +0.05 mm) and femoral IMT (ALA:+0.05 mm; LA:+0.04 mm) was similar, when adjusted for confounding variables. After 1 and 2 y, ALA users had a lower CRP level than LA users (net differences -0.53 and -0.56 mg/l, respectively, P < 0.05). No significant effects were observed in oxidized LDL antibodies, and levels of sICAM-1, interleukins 6 and 10. CONCLUSIONS A six-fold increased ALA intake lowers CRP, when compared to a control diet high in LA. The present study found no effects on markers for atherosclerosis. SPONSORSHIP The Dutch 'Praeventiefonds'.
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Microalbuminuria is related to marked end organ damage in previously untreated, elderly hypertensive patients. Blood Press 2002; 11:84-90. [PMID: 12035876 DOI: 10.1080/08037050211267] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We wondered whether, in an elderly hypertensive population in a primary prevention setting, free from diabetes mellitus and clinical atherosclerosis, differences between end organ damage and microalbuminuria (MA) could be found using a lower level of urinary albumin excretion than that of classically defined MA. From a population survey of 173 previously untreated hypertensive patients (4x blood pressure systolic > or = 160 and < or = 220 mmHg, and/or diastolic > or = 95 and < or = 115 mmHg), mean age 67 +/- 4 years, were screened for MA (defined as albumin excretion between 20 and 300 mg/24 h). End organ damage was determined by B-mode ultrasound scanning of carotid and femoral arteries and echocardiography. Out of 173 hypertensives, 14 showed MA (8%). These hypertensives had a significantly higher intima media thickness (IMT; 1.01 +/- 0.21 vs 0.88 +/- 0.6 mm, p < 0.05) and increased left ventricular mass index (118 +/- 31 vs 103 +/- 22 g/m2, p < 0.05) than hypertensives without MA. Linear regression analysis showed that MA, age, male gender and diastolic blood pressure were independently related to IMT, while systolic blood pressure, male gender and body mass index were independently related to left ventricular mass. Even using lower levels of urinary albumin excretion rate, patients with MA had significantly higher IMT and increased left ventricular mass. Moreover, MA was independently related to IMT in these elderly hypertensives. These results suggest that the threshold value for MA should be reconsidered in hypertension.
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Antineutrophil cytoplasmatic antibodies in patients with premature atherosclerosis: prevalence and association with risk factors. J Intern Med 2002; 251:29-34. [PMID: 11851862 DOI: 10.1046/j.1365-2796.2002.00920.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Autoimmunity is suggested to play a role in premature atherosclerosis. Antineutrophil cytoplasmatic antibodies (ANCA) are a group of autoantibodies found in several inflammatory disorders in which they supposedly amplify the inflammatory process. In this study the hypothesis is tested that ANCA play a role in premature atherosclerosis. DESIGN Cross-sectional study followed by nested case-control study. In a total of 286 consecutive patients with premature atherosclerosis (age < 55 years) ANCA were tested. Within the same cohort, a nested case-control study in 16 ANCA-positive patients and 32 ANCA-negative controls matched for sex, and site of atherosclerosis, was executed. SETTING University hospital outpatient clinic for lipids and premature atherosclerosis. SUBJECTS A total of 286 consecutive patients with premature atherosclerosis (age < 55 years). RESULTS Prevalence of ANCA was 5.6% (16 of 286). All cases had perinuclear ANCA (pANCA); no cytoplasmatic ANCA was found. Mean age was 42 +/- 7 in the ANCA-positive vs. 42 +/- 9 years in the ANCA-negative group (P=ns). More female parents were ANCA-positive (8M/8F vs. 200M/70F, P=0.03). Patients with ANCA had more often peripheral vascular disease (37.5 vs. 15.2%, P=0.03). In the case-control study levels of Lp(a) were higher (43.8 vs. 15.6% >300 mg x L(-1), P=0.05), whereas levels of HDL-c were lower in ANCA-positive patients (0.84 +/- 0.26 vs. 1.06 +/- 0.27 mmol x L(-1), P=0.01). Markers of inflammation, C-reactive protein (CRP) and serum amyloid A (SAA), did not differ, nor did antibodies against oxidized-LDL and malondialdehyde (MDA)-LDL, markers for the extent of atherosclerosis. CONCLUSIONS Our results suggest that ANCA do not appear to play a major role in premature atherosclerosis as there was no increased prevalence of the autoantibody. Moreover, no differences in the incidence of classical cardiovascular risk factors nor in serum levels of markers of inflammation were found between the ANCA-positive group as compared with the ANCA-negative group.
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Secondary prevention with fluvastatin decreases levels of adhesion molecules, neopterin and C-reactive protein. Eur J Intern Med 2001; 12:503-9. [PMID: 11711273 DOI: 10.1016/s0953-6205(01)00172-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Treatment of hypercholesterolaemia with HMG-CoA reductase inhibitors results in an earlier reduction of morbidity and mortality than expected from trials using conventional cholesterol-lowering therapies. Possible explanations for this effect include stimulation of angiogenesis, improvement of endothelial function, plaque stabilisation, inhibition of coagulation and/or thrombocyte aggregation and inhibition of the inflammatory response associated with atherosclerosis. METHODS We investigated whether statins exert their effects by inhibition of endothelial activation, inflammation and/or monocyte/macrophage activation by measuring plasma levels of soluble cell adhesion molecules, neopterin and C-reactive protein upon treatment with fluvastatin for a period of 12 months in patients with established atherosclerosis and hypercholesterolaemia. RESULTS Blood samples were taken at baseline and at 3 and 12 months after starting treatment with fluvastatin 80 mg daily. Upon treatment, a reduction of s-ICAM-1 (956.3+/-123.6 vs. 745.4+/-127.4 vs. 674.9+/-70.8 ng/ml, P<0.05) and s-E-selectin (58.6+/-6.7 vs. 47.0+/-6.1 vs. 44.9+/-3.2 ng/ml, P<0.01) was observed. In addition, levels of neopterin decreased, albeit transiently (7.1+/-0.7 vs. 6.0+/-0.5 vs. 6.5+/-0.8 nmol/l, P=0.02), suggesting a reduction in monocyte/macrophage activity. Moreover, we found a decrease in levels of C-reactive protein during follow-up (5.21+/-2.0 vs. 3.18+/-0.7 vs. 1.95+/-0.3 mg/l, P<0.05), compatible with a reduction in inflammatory activity. CONCLUSION We conclude that statins have a combined beneficial effect on monocyte/macrophage activity, endothelial function and systemic inflammatory activity.
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Abstract
The purpose of this study was to evaluate in a prospective, double-blind, placebo-controlled study the effect of long-term (2-year) lisinopril treatment on cardiovascular end-organ damage in patients with previously untreated isolated systolic hypertension (ISH). All patients with ISH were derived from a population screening program. End-organ damage measurements, done initially and after 6 and 24 months of treatment, included measurements of aortic distensibility and echocardiographic left ventricular mass index (LVMI) and diastolic function. Blood pressure was measured by office and ambulatory measurements. Of the 97 subjects with ISH selected from the screening, 62 (30 lisinopril) completed the study according to protocol. Office blood pressure decreased in both groups, but ambulatory results significantly decreased with lisinopril-treatment only. Aortic distensibility increased significantly with lisinopril, as opposed to a decrease in placebo-treated subjects. The main effect of increased distensibility occurred between 6 and 24 months, whereas ambulatory blood pressure changed mainly in the first 6 months of treatment. LVMI decreased in both treatment groups, with a significantly higher reduction in lisinopril-treated subjects. Left ventricular diastolic function showed no significant changes in either group. The vascular pathophysiologic alterations of ISH-a decreased aortic distensibility-can be improved with long-term lisinopril treatment, whereas values deteriorate further in placebo-treated subjects. These results, in one of the first studies including subjects with previously untreated ISH only, indicate that lisinopril treatment might favorably influence the cardiovascular risk of ISH.
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Abstract
In hypertension, both reduced vascular supply and increased cardiac demand contribute to the development of (silent) myocardial ischemia. Our aim was to determine the prevalence of ST-segment depression and to analyze contributing factors in asymptomatic, previously untreated, older hypertensives. From a population survey, in 184 patients with mild hypertension (4 times systolic blood pressure >/=160 mm Hg and/or diastolic blood pressure >/=95 mm Hg), 60 to 75 years of age, cardiovascular end-organ damage was measured. Episodes of ST-segment depression were measured by 48-hour ambulatory Holter monitoring and were observed in 21 hypertensives (12%). They showed a significantly higher combined far-wall intima-media thickness of carotid and femoral arteries and more arterial plaques as measured by B-mode ultrasound compared with hypertensives without ST depression (0.00098+/-0.00021 versus 0.00088+/-0.00016 mm and 5.2+/-3.7 versus 3.7+/-2.8 plaques, P<0.05, respectively), whereas left ventricular mass index was not different (111+/-18 versus 104+/-24 g/m(2); P=0.18, respectively). In hypertensives with transient ST-segment depression, a significant relation was found between left ventricular mass and ischemic burden (r=0.51, P=0.02). Approximately 1 of 8 unselected and previously untreated older hypertensives show asymptomatic ST-segment depression, suggestive of silent myocardial ischemia. These data suggest that vascular factors mainly determine the occurrence of ischemic ST-segment depression and cardiac factors determine the ischemic burden in older hypertensives.
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Long-term effects of amlodipine and lisinopril on left ventricular mass and diastolic function in elderly, previously untreated hypertensive patients: the ELVERA trial. J Hypertens 2001; 19:303-9. [PMID: 11212974 DOI: 10.1097/00004872-200102000-00018] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare the effects of a calcium antagonist (amlodipine) and an angiotensin converting enzyme inhibitor (lisinopril) on left ventricular mass and diastolic function in elderly, previously untreated hypertensives. DESIGN A double-blind randomized parallel group trial. Effects of amlodipine and lisinopril on left ventricular mass and diastolic function (E/A Ratio) (The ELVERA trial). SETTING Rural northern Netherlands: population screening new diagnosed hypertensive subjects. PATIENTS The study population comprised 166 newly diagnosed hypertensive (aged 60-75) with diastolic blood pressure between 95-115 mmHg and/or systolic blood pressure between 160-220 mmHg. INTERVENTION Patients were randomly allocated to receive 5-10 mg amlodipine or 10-20 mg lisinopril for 2 years. MAIN OUTCOME MEASURES Prior and after 1 and 2 years of treatment left ventricular mass, indexed by body surface (LVMI) was estimated by 2-D mode echocardiography according to Devereux with use of Penn convention. Early to atrial filling ratio (E/A) was assessed by transmitral flow. Change from baseline of LVMI and E/A ratio was evaluated by repeated measurement analysis of the treatment effect in an intention-to-treat analysis. RESULTS Both amlodipine and lisinopril led to equivalent reduction in systolic and diastolic blood pressure. At the end of the study the amlodipine group led to LVMI decrease by 21.8 g/m < or = [95% confidence interval (CI), 18.3-25.3] and E/A ratio increased by 0.08 (95% CI, 0.05-0.11). In the lisinopril group LVMI decreased by 22.4 g/m < or = (95%, CI, 19.0-25.8) and E/A ratio increased by 0.07 (95% CI, 0.04-0.10). No statistically significant differences were found in changes in LVMI and E/A ratio between amlodipine and lisinopril. CONCLUSION A long-term study, the ELVERA trial proves that amlodipine and lisinopril reduce left ventricular mass and improve diastolic function to a similar extent in elderly newly diagnosed hypertensive patients.
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Associations of alpha-linolenic acid and linoleic acid with risk factors for coronary heart disease. Eur J Clin Nutr 2000; 54:865-71. [PMID: 11114683 DOI: 10.1038/sj.ejcn.1601102] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Prevention of coronary heart disease (CHD) in high-risk subjects. OBJECTIVE To investigate the associations of dietary intake of alpha-linolenic acid (ALA) and linoleic acid (LA) as assessed by food frequency questionnaire and in the plasma cholesteryl ester (CE), with CHD risk factors. DESIGN Baseline data of a double-blind, randomized placebo-controlled trial. Subjects have hypercholesterolemia (6.0-8.0 mmol/l) and at least two other CHD risk factors (n=266). RESULTS The reported dietary ALA and LA intakes and the LA/ALA ratio were associated with the contents in the CE (r=0.37, r=0.21, and r=0.42, respectively; P<0.01). In multivariate analysis, CE ALA was inversely associated with diastolic blood pressure (r=-0.13; P<0.05) and positively with serum triacylglycerol (r=0.13; P<0.05), and CE LA was inversely associated with serum triacylglycerol (r=-0.32; P<0.01). The CE LA/ALA ratio was strongly inversely associated with CE ALA (r=-0.95; P<0.01). In the lowest quintile of CE ALA, mean dietary intake was 0.4 energy % ALA (1.2 g/day), 8.4 energy % LA and an LA/ALA ratio of 21, and in the highest quintile 0.6 energy % ALA (1.7 g/day), 6.8 energy % LA and 12 (ratio). In the lowest quintile of CE ALA the diastolic blood pressure was 4 mm Hg lower (P trend<0.05), and the serum triacylglycerol 0.3 mmol/l higher (P trend NS) when compared with the top quintile. CONCLUSIONS In a CHD high-risk population with LA-rich background diet, these cross-sectional data suggest that replacing LA in the diet by ALA may decrease diastolic blood pressure, and may increase serum triacylglycerol concentration.
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Abstract
Due to the results of antihypertensive intervention studies, isolated systolic hypertension (ISH) has gained new interest lately. Yet, apart from increased aortic stiffness, the specific pathophysiological features of ISH have remained largely undetermined. Therefore, we investigated the elastic properties of the vascular bed of an upper arm segment in uncomplicated ISH patients and matched normotensive controls using an electrical bioimpedance technique. Compared with the controls, the compliance of the arterial bed as a whole at normotensive blood pressure level was on the average 108.0% higher (p < 0.005) in the hypertensive patients. The blood volume of the arterial bed as a whole at operating blood pressure level and that of the larger arteries were significantly higher (40.5%, p < 0.05, and 40.5%, p < 0.01, respectively). The same held true for the venous blood volume (64.4%, p < 0.05), and for the width of the arterial compliance-pressure relation (34.6%, p < 0.01). We concluded that ISH is a separate pathophysiological entity in which all parts of a peripheral vascular bed are changed and the decreased buffering function of the aorta and large arteries is partly compensated for by an increase in small artery compliance.
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Impact of Mediterranean diet education versus posted leaflet on dietary habits and serum cholesterol in a high risk population for cardiovascular disease. Public Health Nutr 2000; 3:273-83. [PMID: 10979147 DOI: 10.1017/s1368980000000318] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To investigate the impact of intensive group education on the Mediterranean diet on dietary intake and serum total cholesterol after 16 and 52 weeks, compared to a posted leaflet with the Dutch nutritional guidelines, in the context of primary prevention of cardiovascular disease (CVD). DESIGN Controlled comparison study of an intervention group given intensive group education about the Mediterranean diet and a control group of hypercholesterolaemic persons given usual care by general practitioners (GPs). SETTING A socioeconomically deprived area in the Netherlands with an elevated coronary heart disease (CHD) mortality ratio. SUBJECTS Two hundred and sixty-six hypercholesterolaemic persons with at least two other CVD risk factors. RESULTS After 52 weeks, the intervention group decreased total and saturated fat intake more than the control group (net differences were 1.8 en% (95%CI 0.2-3.4) and 1.1 en% (95%CI 0. 4-1.9), respectively). According to the Mediterranean diet guidelines the intake of fish, fruit, poultry and bread increased in the intervention group, more than in the control group. Within the intervention group, intake of fish (+100%), poultry (+28%) and bread (+6%) was significantly increased after 1 year (P < 0.05). The intensive programme on dietary education did not significantly lower serum cholesterol level more (-3%) than the posted leaflet (-2%) (net difference 0.06 mmol l-1, 95%CI -0.10 to 0.22). Initially, the body mass index (BMI) decreased more in the intervention group, but after 1 year the intervention and control group gained weight equally (+1%). CONCLUSIONS Despite beneficial changes in dietary habits in the intervention group compared with the control group, after 1 year BMI increased and total fat and saturated fat intake were still too high.
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Home blood pressure measurement: reproducibility and relationship with left ventricular mass. Blood Press Monit 1999; 4:65-9. [PMID: 10450121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE To evaluate the reproducibility and relationship with left ventricular mass index of home blood pressure in comparison with ambulatory and office blood pressures. METHODS We measured home, ambulatory and office blood pressures of 84 previously untreated hypertensive patients, aged 60-74 years, from primary care, at baseline and after 12 weeks, without active intervention in between. Left ventricular mass index was determined echocardiographically during week 12. RESULTS Decreases in systolic and diastolic blood pressures were found after 12 weeks for mean home and office blood pressures (P<0.05), but not for mean ambulatory blood pressure. The coefficients of reproducibility for systolic and diastolic ambulatory blood pressures were 26.4 and 16.0, respectively. Correlation coefficients for correlation of left ventricular mass index to ambulatory blood pressure (0.51 and 0.36) were higher than the correlation coefficients for home (0.31 and 0. 16) and office (0.32 and 0.21) blood pressures, for systolic and diastolic values, respectively. However, we could find no statistically significant difference among the correlation coefficients for all three types of measurements. CONCLUSIONS Home blood pressure was considerably less reproducible than ambulatory blood pressure and no different from office blood pressure in this respect. The relationship with left ventricular mass index appeared to be stronger for ambulatory than it was for home and office blood pressures, although not statistically significant so.
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Abstract
Recent data have shown that left ventricular (LV) geometry provides additional information on the simple dichotomy of presence or absence of LV hypertrophy with regard to cardiovascular risk of hypertensive patients. A "new" class of concentric remodeling was created, identifying a rather large group of hypertensive patients who do have increased risk despite no LV hypertrophy. Because determination of LV geometry is not easy, our objective was to develop a nomogram enabling determination of LV geometry in a simple way. The geometric classification is based on the combination of increased relative wall thickness and LV hypertrophy (LV mass index > or = 125 g/m2) both of which are calculated from wall thickness and end-diastolic diameter. In the nomogram the calculated cutoff lines for relative wall thickness and left ventricular hypertrophy are plotted, forming 4 quadrants that represent the geometric classes. Two nomograms are made: 1 based on Penn convention measurement calculations and 1 based on American Society of Echocardiography convention measurements. This nomogram provides a simple way to determine LV geometry, and thus a quick assessment of the additional cardiovascular risk of the hypertensive patient. This is especially important for subjects with concentric remodeling, who would otherwise not be identified as having increased risk for cardiovascular disease.
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Effects of amlodipine and lisinopril on left ventricular mass and diastolic function in previously untreated patients with mild to moderate diastolic hypertension. Blood Press 1998; 7:109-17. [PMID: 9657538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The aim of the study was to compare the effects of two long-acting antihypertensive agents, the calcium-antagonist amlodipine and the ACE inhibitor lisinopril, on left ventricular mass and diastolic filling in patients with mild to moderate diastolic hypertension from primary care centres. It is a 1-year prospective, double-blind, randomized, parallel group, comparative study. Patients between 25 and 75 years of age with untreated hypertension with elevated diastolic blood pressure (> or = 95 mmHg) on three occasions (twice on the first visit and once only on the second and third visits) were recruited from a population survey. After 4 weeks placebo run-in 71 patients were randomized to dosages of amlodipine 5-10 mg or lisinopril 10-20 mg, which were titrated on the basis of the effects on blood pressure. Fifty-nine patients completed the study period. Primary endpoints were left ventricular mass index and early to atrial peak filling velocity. Office and ambulatory blood pressure and other echocardiographic measurements were considered secondary. Decrease in blood pressure was equal for both treatment regimens. A statistically significant decrease in left ventricular mass index in both treatment groups was observed: -11.0 g/m2 (95% CI: -6.0, -16.1) in the amlodipine group and -12.6 g/m2 (95% CI: -8.2, -17.0) in the lisinopril group. The higher the baseline value of left ventricular mass before treatment, the more the decrease after treatment. Early to atrial peak filling velocity did not change significantly within the treatment groups: +0.07 (95% CI: -0.01, +0.15) in the amlodipine group and +0.01 (95% CI: -0.06, +0.08) in the lisinopril group. However, analysis of time measurements of the early peak showed significant changes for both treatment groups. No significant differences in primary and secondary endpoints between treatment groups were found. Twelve patients did not complete the study, seven in amlodipine and five in lisinopril, basically due to adverse events. The effects of amlodipine and lisinopril on left ventricular mass and early to atrial filling peak velocity after 1 year of treatment in patients with previously untreated mild to moderate hypertension are similar. Further studies are recommended, particularly with a larger sample size and a follow-up of longer duration.
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[Aids in Madagascar. II. Intervention policy for maintaining low HIV infection prevalence]. BULLETIN DE LA SOCIETE DE PATHOLOGIE EXOTIQUE (1990) 1998; 91:71-3. [PMID: 9559169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The HIV seroprevalence per 100,000 adults Malagasy rose from 20 in 1989, to 30 in 1992, and to 70 in 1995. In that year, the total number of HIV infected people in the Big Island was estimated at 5,000, the number of people sick with AIDS at 130, and the people at risk at more than 1,000,000. The latter are the persons infected with other STDs and individuals (or their partners) with risky sexual behaviour (e.g. numerous sexual partners, occasional sexual partners, and/or sexual contacts with commercial sex workers). The HIV prevalence rate is low as compared with those of other countries. Nevertheless, the spread of the HIV infection is alarming in some parts of the country and the risk factors are also present, namely: the high prevalence of STDs, numerous sexual partners, the low use of condoms in all groups, the development of tourism, the development of prostitution associated with social and economical problems, and internal and international migrations (with risky sexual contacts). Therefore, the still low but rising HIV prevalence in 1995 does not warrant complacency. To estimate the trend of HIV prevalence within the population, it is useful to know two different assumptions, as follows: firstly, a controlled evolution of the epidemic (low epidemic) and secondly, a very fast spread of the epidemic (high epidemic). If we consider the 5,000 individuals seropositive in July 1995, the Aids Impact Model (AIM) projection model shows that HIV seroprevalence rates among adults in 2015 might be between 3% (when the progression course of HIV epidemic is low) and 15% (when the progression course of HIV epidemic is high). By 2015 AIDS could have severe demographic, social, and economic impacts. Then, it is necessary to take measures to prevent contamination. Five major interventions are required: public information about AIDS, HIV transmission mechanism, and its prevention, communities education via the respected people and the notabilities to promote moral values, reduce the number of sexual partners, delay visit of sexual activity, and advice for infected couples; screening of blood donors and the supposed high risk group; control of STDs; reduction of the number of sexual partners; promotion of condom use, abstinence, and fidelity. To sum up, the fight against AIDS is not only the health professional workers' problem. It concerns all Malagasy people. Therefore, successfullness in prevention efforts to slow the epidemic needs concerted, collective, and long lasting actions from all sectors of the society for the nation's future and the well-being of the rising generations.
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[AIDS in Madagascar. I. Epidemiology, projections, socioeconomic impact, interventions]. BULLETIN DE LA SOCIETE DE PATHOLOGIE EXOTIQUE (1990) 1998; 91:68-70. [PMID: 9559168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Madagascar is still among the rare states of low prevalence of HIV. The seroprevalence rate is nevertheless rising. The aim of this study is to show the current view of the epidemic, its future tendency, its economical and social impact on people and what measures to be taken at the national scale. In Madagascar, we can state by 1995 20 cases of notified AIDS and probably 130 cases of non-notified AIDS. Seroprevalence data are collected every year by the National Reference Laboratory STD/AIDS. But, they are insufficient to estimate the number of infected people. So, they had been completed by a serosurveillance study of AIDS and syphilis in middle of 1995 and at the beginning of 1996. Pregnant women, persons with STDs and prostitutes are been screened in the six biggest cities of the Island. Results show, not only a high prevalence of syphilis, but also indicate that now, we have about 5,000 seropositive people in the country. Besides, by the number of people with STDs, it is estimated that one million Malgasy adults risk to be infected. Based on estimates of the epidemic, be it the cases of a high scenario, (Kenya) or of a low one (Thailand) by the year 2015, the seroprevalence rate could represent 3% or 15% of adults. Demographic consequences of the epidemic will be serious, particularly if HIV spreads quickly. Nevertheless, it does not stop the increase of population. Therefore, there will be more infected people with the disease, especially young people between 15 and 49 years old. The increase of dead people will be serious. Social consequences of the epidemic (case of high scenario) will be gravely felt, in particular by the rise of the number of AIDS orphans. Tuberculosis outbreak can be observed too. This disease is already a serious problem in Madagascar. At last, the epidemic will bring with it a high increase of money spent on health and will have grave consequences on agriculture, industry and commerce. Nevertheless, Madagascar still benefit a big luck which is the prevention of the epidemic not to be exploded in a near future. For this, struggle against it is particularly effective on its start. In addition to counselling given to infected people and care-given to patients, means of prevention of AIDS contamination in all target groups must be set up quickly. It is about broadcasting information on AIDS, community education, controlling other STDs e.g. (importance of medicaments' program), promoting the use of condoms and screening HIV new cases. Only an urgent coordination of everyone's efforts can control the epidemic of AIDS.
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Effect of quinapril and triamterene/hydrochlorothiazide on cardiac and vascular end-organ damage in isolated systolic hypertension. J Cardiovasc Pharmacol 1998; 31:187-94. [PMID: 9475259 DOI: 10.1097/00005344-199802000-00003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We compared, in a prospective double-blind randomized study, the effect of the angiotensin-converting enzyme inhibitor quinapril (QUI) with that of triamterene/hydrochlorothiazide (THCT) treatment on cardiovascular end-organ damage in subjects with untreated isolated systolic hypertension (ISH). End-organ damage measurements, performed initially and after 6 and 26 weeks of treatment, included echocardiographic determination of left ventricular mass index (LVMI) and of diastolic function and measurement of aortic distensibility and peripheral vascular resistance. Blood pressure was significantly reduced in the 44 subjects (21 QUI, 23 THCT) completing the study. Both LVMI and aortic distensibility had changed at 6 weeks, with comparable improvements in both groups. LV diastolic function showed overall no significant changes, although patterns of early filling did differ between the two drug groups. Peripheral vascular resistance appeared to increase between 6 and 26 weeks in THCT subjects only, along with a decreased aortic distensibility. Blood pressure and LV mass were rapidly and markedly reduced in both treatment groups of ISH subjects, paralleled by an improvement of aortic distensibility. In interpreting these results, the pathophysiologic alterations in ISH need to be taken into account, because these differ strongly from those in diastolic hypertension. Results of LV diastolic function and peripheral vascular resistance were less clear but appear to show less favorable changes in the THCT subjects treatment group.
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Dyslipidemia and endothelium-dependent relaxation in internal mammary arteries used for coronary bypass surgery. Cardiovasc Res 1997; 34:568-74. [PMID: 9231040 DOI: 10.1016/s0008-6363(97)00081-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE Impairment of endothelium-dependent relaxation is related to dyslipidemia and may be an early marker for atherosclerosis in angiographically smooth arteries. The aim of the present study was to relate preoperative serum lipids to endothelium-dependent relaxation in internal mammary arteries of patients undergoing coronary bypass surgery. METHODS The study group consisted of 37 patients, from whom segments of the internal mammary artery were obtained during surgery. Measurements of endothelium-dependent relaxation were performed in organ baths by adding methacholine (10 nM-10 microM). RESULTS All internal mammary arteries dilated in response to methacholine, ranging from 4 to 112% of the precontraction to 10 mumol phenylephrine. In a multiple regression model, increased total serum cholesterol appeared to be the best predictor for impaired endothelium-dependent relaxation. A 1 mmol increase of total cholesterol was associated with a 11.2% decrease of endothelium-dependent relaxation (P = 0.006). When total cholesterol was omitted from the model, LDL-cholesterol became the best predictor of endothelium-dependent relaxation (regression coefficient 10.3%/mmol; P = 0.02). No other variable was significantly associated with endothelium-dependent relaxation, and none of the preoperative variables was associated with endothelium-independent relaxation, expressed as the response to sodium nitrite (10 mM). CONCLUSION Our study showed that endothelium-dependent relaxation in apparently non-diseased internal mammary arteries used for coronary bypass surgery was independently related to preoperative (LDL)-cholesterol levels.
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High prevalence of concentric remodeling in elderly individuals with isolated systolic hypertension from a population survey. Hypertension 1997; 29:539-43. [PMID: 9040435 DOI: 10.1161/01.hyp.29.2.539] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Echocardiographic determination of left ventricular mass index (LVMI) is shown to be valuable in the assessment of cardiovascular risk. Determination of left ventricular geometry, including concentric remodeling, provides additional prognostic information. In isolated systolic hypertension (ISH), the few echocardiographic studies available show an increased LVMI, but criteria and patient populations differ. No comparison with diastolic hypertension (DH) has been made, nor has left ventricular geometry (with concentric remodeling) been evaluated. We compared both LVMI and left ventricular geometry of newly diagnosed ISH subjects with normotensive and DH subjects, all previously untreated and from the same population. The echocardiographic LVMI of 97 previously untreated ISH subjects (4 x systolic pressure > or = 160 mm Hg, diastolic pressure < 95 mm Hg) was clearly elevated compared with values in age- and sex-matched normotensive subjects (98 and 71 g/m2, respectively; P < .001). The geometric pattern was abnormal in most ISH subjects, with a high prevalence (43%) of concentric remodeling. Both LVMI and left ventricular geometry of ISH subjects did not differ significantly from values in DH subjects (LVMI, 92 g/m2; concentric remodeling, 56%). Sex differences in LV geometry in ISH were present only with the Framingham criteria, not with the Koren criteria. This study shows a high prevalence of concentric remodeling in elderly individuals with previously untreated ISH. The increase of LVMI and abnormality in left ventricular geometry are comparable with those in DH subjects, further defining the place of ISH as a cardiovascular risk factor in the elderly. Whether there are sex differences in cardiac adaptation in ISH and whether the geometric classification can be used to adjust treatment remain to be investigated.
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Acceptance and side effects of ambulatory blood pressure monitoring: evaluation of a new technology. J Hum Hypertens 1996; 10 Suppl 3:S39-42. [PMID: 8872824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Ambulatory blood pressure (BP) monitoring is probably becoming a clinically useful procedure for the evaluation of hypertensive patients. Previous reports have shown that the devices are safe and serious side effects are rare. Discomfort and inconveniences associated with its use are more frequent. In this study, patient acceptance of ambulatory blood pressure monitoring (ABPM) was compared with acceptance of other diagnostic procedures and their side effects were assessed. Patients were asked to fill in a form and 129 of 166 patients responded. The acceptance was measured with a visual analogue scale which ranged from 'very annoying' on the left to 'not annoying at all' on the right. All forms were collected anonymously. Mean distance (cm) of the visual likert scale was 8.6 to 9.4 for the diagnostic procedures frequently used in routine patient care. Ambulatory BP measurement (ABPM) scored 6.1 cm. Reported side effects (in 27% of patients) were: plan (9%), skin irritation (8%), noisy device (8%), inconvenience with work (3%), haematoma (2%) and other (4%). Reports from the patients on sleep quality were: 23% normal, 61% minor disturbance, 14% had sleep, and 2% did not sleep at all. It can be concluded that ambulatory BP monitoring was the diagnostic procedure with the lowest patient acceptance. Side effects of this new technology were reported by 27% of patients. However, risks are relatively minor. Sleep disturbances were very frequent and was a serious problem for 16% of patients.
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Predictive value of ambulatory blood pressure shortly after withdrawal of antihypertensive drugs in primary care patients. BMJ (CLINICAL RESEARCH ED.) 1996; 313:404-6. [PMID: 8761232 PMCID: PMC2351811 DOI: 10.1136/bmj.313.7054.404] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine whether ambulatory blood pressure eight weeks after withdrawal of antihypertensive medication is a more sensitive measure than seated blood pressure to predict blood pressure in the long term. DESIGN Patients with previously untreated diastolic hypertension were treated with antihypertensive drugs for one year; these were withdrawn in patients with well controlled blood pressure, who were then followed for one year. SETTING Primary care. SUBJECTS 29 patients fulfilling the criteria for withdrawal of antihypertensive drugs. MAIN OUTCOME MEASURES Sensitivity, specificity, and positive and negative predictive value of seated and ambulatory blood pressure eight weeks after withdrawal of antihypertensive drugs. RESULTS Eight weeks after withdrawal of medication, mean diastolic blood pressure returned to the pretreatment level on ambulatory measurements but not on seated measurements. One year after withdrawal of medication, mean diastolic blood pressure had returned to the pretreatment level both for seated and ambulatory blood pressure. For ambulatory blood pressure, the sensitivity and the positive predictive value eight weeks after withdrawal of medication were superior to those for seated blood pressure; specificity and negative predictive value were comparable for both types of measurement. Receiver operating characteristic curves showed that the results were not dependent on the cut off values that were used. CONCLUSION Ambulatory blood pressure eight weeks after withdrawal of antihypertensive drugs predicts long term blood pressure better than measurements made when the patient is seated.
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Coronary angioscopy confirms the presence of red thrombus in acute myocardial infarction after blunt chest trauma. Am Heart J 1996; 131:1216-8. [PMID: 8644603 DOI: 10.1016/s0002-8703(96)90099-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Abstract
Although echocardiography provides a reliable method to determine left ventricular (LV) mass, it may not be available in all settings. Numerous electrocardiographic (ECG) criteria for the detection of LV hypertrophy have been developed, but few attempts have been made to predict the LV mass itself from the ECG. In a community-based survey program in the general population, 277 subjects were identified with untreated diastolic hypertension (diastolic blood pressure 95 to 115 mm Hg, 3 occasions) or isolated systolic hypertension (diastolic blood pressure <95 mm Hg and systolic blood pressure 160 to 220 mm Hg, 3 occasions). All subjects underwent ECG and echocardiography on the same day. A multiple linear regression analysis was performed using a random training sample of the data set (n = 185). The independent variables included both ECG and non-ECG variables. The resulting model was used to predict the LV mass in the remainder of the data set, the validation sample (n = 92). Using sex, age, body surface area, the S-voltage in V1 and V4, and the duration of the terminal P in V1 as independent variables, the model explained 45% of the variance (r = 0.67) in the training sample and 42% (r = 0.65) in the validation sample. This result exceeded that of 2 existing ECG models for LV mass (r = 0.40 and 0.41). The correlations between LV mass and combinations of ECG variables used for the detection of LV hypertrophy, such as the Sokolow-Lyon Voltage (r = 0.03) and the Cornell Voltage (r = 0.31), were comparatively low. In settings where echocardiography is not available or is too expensive and time-consuming, prediction of the LV mass from the ECG may offer a valuable alternative.
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Abstract
This article discusses various aspects of cholesterol-lowering therapy using the HMG-CoA reductase inhibitor simvastatin in the light of the large Scandinavian Simvastatin Survival Study (4S). In 4S, patients with proven coronary heart disease (CHD) and plasma total cholesterol > 5.5 mmol/L (212 mg/dl) despite dietary measures received statin therapy or placebo for > or = 5 years. A significant mortality reduction was accomplished in those receiving the statin. Moreover, a significant decrease of nonfatal myocardial infarction and requirement for coronary bypass surgery or angioplasty was demonstrated, which will contribute to the cost-effectiveness of this well tolerated therapy. Plaque stabilisation and improvement of endothelial function are thought to be mediators of this therapeutic success. Responsible drug prescription in the post-4S era may result in the recognition and treatment of more patients with CHD. This is likely to be more beneficial than exhaustive efforts to completely achieve the goals of the most strict guidelines in the individual patient. In patients who carry the highest absolute risk for a recurrent event, aggressive drug therapy may be most justified. Reluctance to initiate lipid lowering drug therapy in patients with proven CHD should now be disputed.
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Comparative effects of diltiazem and lisinopril on left ventricular structure and filling in mild-to-moderate hypertension. J Cardiovasc Pharmacol 1995; 26:983-9. [PMID: 8606538 DOI: 10.1097/00005344-199512000-00020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The comparative effects on echocardiographically determined left ventricular (LV) mass and pulsed Doppler derived indexes of LV diastolic filling were studied in previously untreated hypertensive patients after 6 months of treatment with diltiazem 300 mg once daily (o.d.) (n = 16), and lisinopril 20 mg o.d. (n = 20). LV mass index decreased in the lisinopril group (from 98 to 96 g/m2; mean difference after 6 months of treatment with diltiazem-lisinopril was 13.7 g/m2 [95% confidence interval (CI) 0.8 to 26.6, p < 0.05]. In both groups diastolic filling parameters improved, but there was no statistically significant difference between the groups. Both treatment regimens showed a similar decrease in office and maximal exercise systolic blood pressure (SPB). Ambulatory daytime BP was lower after lisinopril treatment (from 147/96 to 126/83 mm Hg) than after diltiazem treatment (from 142/93 to 135/87 mm Hg); mean difference between diltiazem and lisinopril after 6 months of treatment was 9.7 (95% CI 3.4 to 16.0, p < 0.05)/9.4 (95% CI 2.5 to 16.3, p < 0.05) mm Hg. Nighttime BP decreased from 129/81 to 113/70 mm Hg in the lisinopril group, but not in the diltiazem group (from 125/79 to 122/77 mm Hg); mean difference between diltiazem and lisinopril after 6 months of treatment was 4.4 (95% CI - 0.2 to 8.9)/6.6 (95% CI 1.1 to 12.0) mm Hg. Changes in diastolic filling parameters were significantly correlated with changes in LV mass index in the lisinopril group, suggesting that the improvements in diastolic filling in the diltazem group may be partly due to an effect on factors other than LV mass.
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Hypertension and left ventricular hypertrophy in black people. J Hum Hypertens 1995; 9:205-6. [PMID: 7783104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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[Rapidly progressive aortic insufficiency in a female patient with rheumatoid arthritis]. NEDERLANDS TIJDSCHRIFT VOOR GENEESKUNDE 1994; 138:618-21. [PMID: 8145866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In a 23-year-old woman with severe rheumatoid arthritis, a rapidly progressive aortic regurgitation (onset within 2 years) was observed. She had a high IgM rheumatoid factor titre and nailfold lesions. The differential diagnosis from infectious endocarditis was difficult. The patient's aortic valve was replaced with a St. Jude mechanical prosthesis. The aortic valve was tricuspid with thick sclerotic cusps and sterile ulcerations and vegetations on the left and right coronary cusps. Histopathologic examination showed hyaline degenerative changes and plasma cell infiltrates in the stroma of the cusps, associated with rheumatoid arthritis. In the literature, aortic regurgitation is associated with longstanding rheumatoid arthritis, subcutaneous nodules, a high IgM rheumatoid factor titre and (or) signs of vasculitis.
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Comparative study of diltiazem and lisinopril in hypertension: similar improvements in diastolic function despite different effects on left ventricular mass and ambulatory blood pressure. JOURNAL OF HYPERTENSION. SUPPLEMENT : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF HYPERTENSION 1993; 11:S366-7. [PMID: 8158425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Characterization of hypertensive subjects who become normotensive during three months of office BP follow-up: comparison with subjects with sustained hypertension and normotensives, and follow-up after two years. J Hum Hypertens 1993; 7:509-14. [PMID: 8263894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
After an observation period of three months, 83% of new hypertensives (n = 84), identified in a population survey, became normotensive. Those with sustained hypertension (n = 14) were compared with 14 initially hypertensives who became normotensive and 14 normotensives, matched for age and sex, using ambulatory and exercise BP and echocardiography (both M-mode and Doppler). The initially hypertensive group (n = 11) was re-examined after two years follow-up. The 24h mean ambulatory and submaximal systolic exercise BP did not differ between sustained (139/92 and 210 mmHg) and initially hypertensives (143/95 and 217 mmHg), being significantly lower in the normotensive group (129/85 and 198 mmHg). Left ventricular mass did not differ between the initially hypertensive and the normotensive groups, being significantly higher in the sustained hypertensives. In both hypertensive groups, as compared with normotensives, the ratio between flow velocity in early and late diastole (E/A ratio) tended to be lower and the early diastolic deceleration time (DT) was significantly shorter. After two years, in the untreated initially hypertensives, office DBP had increased to hypertensive values, without change in ambulatory BP, left ventricular mass or early diastolic deceleration time. The E/A ratio had decreased to a level < 1. We conclude that the subjects who became normotensive after three months office BP follow-up have a BP load and signs of compromised left ventricular diastolic function similar to that of the sustained hypertensives, but without increased left ventricular mass.(ABSTRACT TRUNCATED AT 250 WORDS)
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