Chronic treatment of hypertensive patients with converting enzyme inhibitors.

It is widely accepted that pharmacologic reduction of the blood pressure of hypertensive patients reduces the risk of at least some of the major cardiovascular complications (1-5). All major studies were carried out before orally active converting enzyme inhibitors had become available. In other words, very effective antihypertensive drugs have been around for quite some time and have already proven their efficacy. Therefore, the considerable enthusiasm that has developed during the very recent years for the new converting enzyme inhibitors should be evaluated in the light of previously available antihypertensive drugs, the more so, as drugs cheaper than converting enzyme inhibiting agents are presently available. Thus, the increased expense when using this new class of antihypertensive compounds should be justified by a therapeutic gain. When evaluating a class of antihypertensive drugs such as converting enzyme inhibitors, there are basically three main considerations: What is their efficacy in long-term use? This includes the effect on blood pressure, on heart, on hemodynamics, and on blood flow distribution. What are the metabolic effects? What is the effect on sodium and potassium excretion? How are the serum lipids affected by its use? Are there any untoward effects related either to the chemical structure of the compound per se or rather to the approach? In particular, are there any central effects of the drug which can cause discomfort to the patient? The following discussion has the principal aim to review these aspects with chronic use of oral converting enzyme inhibiting agents without, however, even attempting to provide an exhaustive review of the subject.

Magnetic pill tracking : a novel non-invasive tool for investigation of human digestive motility

RESUME Les améliorations méthodologiques des dernières décennies ont permis une meilleure compréhension de la motilité gastro-intestinale. Il manque toutefois une méthode qui permette de suivre la progression du chyme le long du tube gastro-intestinal. Pour permettre l'étude de la motilité de tout le tractus digestif humain, une nouvelle technique, peu invasive, a été élaborée au Département de Physiologie, en collaboration avec l'EPFL. Appelée "Magnet Tracking", la technique est basée sur la détection du champ magnétique généré par des matériaux ferromagnétiques avalés. A cet usage, une pilule magnétique, une matrice de capteurs et un logiciel ont été développés. L'objet de ce travail est de démontrer la faisabilité d'un examen de la motilité gastro-intestinale chez l'Homme par cette méthode. L'aimant est un cylindre (ø 6x7 mm, 0.2 cm3) protégé par une gaine de silicone. Le système de mesure est constitué d'une matrice de 4x4 capteurs et d'un ordinateur portable. Les capteurs fonctionnent sur l'effet Hall. Grâce à l'interface informatique, l'évolution de la position de l'aimant est suivie en temps réel à travers tout le tractus digestif. Sa position est exprimée en fonction du temps ou reproduite en 3-D sous forme d'une trajectoire. Différents programmes ont été crées pour analyser la dynamique des mouvements de l'aimant et caractériser la motilité digestive. Dix jeunes volontaires en bonne santé ont participé à l'étude. L'aimant a été avalé après une nuit de jeûne et son séjour intra digestif suivi pendant 2 jours consécutifs. Le temps moyen de mesure était de 34 heures. Chaque sujet a été examiné une fois sauf un qui a répété sept fois l'expérience. Les sujets restaient en décubitus dorsal, tranquilles et pouvaient interrompre la mesure s'ils le désiraient. Ils sont restés à jeûne le premier jour. L'évacuation de l'aimant a été contrôlée chez tous les sujets. Tous les sujets ont bien supporté l'examen. Le marqueur a pu être détecté de l'oesophage au rectum. La trajectoire ainsi constituée représente une conformation de l'anatomie digestive : une bonne superposition de celle-ci à l'anatomie est obtenue à partir des images de radiologie conventionnelle (CT-scan, lavement à la gastrografine). Les mouvements de l'aimant ont été caractérisés selon leur périodicité, leur amplitude ou leur vitesse pour chaque segment du tractus digestif. Ces informations physiologiques sont bien corrélées à celles obtenues par des méthodes établies d'étude de la motilité gastro-intestinale. Ce travail démontre la faisabilité d'un examen de la motilité gastro-intestinal chez l'Homme par la méthode de Magnet Tracking. La technique fournit les données anatomiques et permet d'analyser en temps réel la dynamique des mouvements du tube digestif. Cette méthode peu invasive ouvre d'intéressantes perspectives pour l'étude de motilité dans des conditions physiologiques et pathologiques. Des expériences visant à valider cette approche en tant que méthode clinique sont en voie de réalisation dans plusieurs centres en Suisse et à l'étranger. SUMMARY Methodological improvements realised over the last decades have permitted a better understanding of gastrointestinal motility. Nevertheless, a method allowing a continuous following of lumina' contents is still lacking. In order to study the human digestive tract motility, a new minimally invasive technique was developed at the Department of Physiology in collaboration with Swiss Federal Institute of Technology. The method is based on the detection of magnetic field generated by swallowed ferromagnetic materials. The aim of our work was to demonstrate the feasibility of this new approach to study the human gastrointestinal motility. The magnet used was a cylinder (ø6x7mm, 0.2 cm3) coated with silicon. The magnet tracking system consisted of a 4x4 matrix of sensors based on the Hall effect Signals from the sensors were digitised and sent to a laptop computer for processing and storage. Specific software was conceived to analyse in real time the progression of the magnet through the gastrointestinal tube. Ten young and healthy volunteers were enrolled in the study. After a fasting period of 12 hours, they swallowed the magnet. The pill was then tracked for two consecutive days for 34 hours on average. Each subject was studied once except one who was studied seven times. Every subject laid on his back for the entire experiment but could interrupt it at anytime. Evacuation of the magnet was controlled in all subjects. The examination was well tolerated. The pill could be followed from the esophagus to the rectum. The trajectory of the magnet represented a "mould" of the anatomy of the digestive tube: a good superimposition with radiological anatomy (gastrografin contrast and CT) was obtained. Movements of the magnet were characterized by periodicity, velocity, and amplitude of displacements for every segment of the digestive tract. The physiological information corresponded well to data from current methods of studying gastrointestinal motility. This work demonstrates the feasibility of the new approach in studies of human gastrointestinal motility. The technique allows to correlate in real time the dynamics of digestive movements with the anatomical data. This minimally invasive method is ready for studies of human gastrointestinal motility under physiological as well as pathological conditions. Studies aiming at validation of this new approach as a clinically relevant tool are being realised in several centres in Switzerland and abroad. Abstract: A new minimally invasive technique allowing for anatomical mapping and motility studies along the entire human digestive system is presented. The technique is based on continuous tracking of a small magnet progressing through the digestive tract. The coordinates of the magnet are calculated from signals recorded by 16 magnetic field sensors located over the abdomen. The magnet position, orientation and trajectory are displayed in real time. Ten young healthy volunteers were followed during 34 h. The technique was well tolerated and no complication was encountered, The information obtained was 3-D con-figuration of the digestive tract and dynamics of the magnet displacement (velocity, transit time, length estimation, rhythms). In the same individual, repea-ted examination gave very reproducible results. The anatomical and physiological information obtained corresponded well to data from current methods and imaging. This simple, minimally invasive technique permits examination of the entire digestive tract and is suitable for both research and clinical studies. In combination with other methods, it may represent a useful tool for studies of Cl motility with respect to normal and pathological conditions.

The antioxidant effect of β-caryophyllene protects rat liver from carbon tetrachloride-induced fibrosis by inhibiting hepatic stellate cell activation.

Plant-based whole foods provide thousands of bioactive metabolites to the human diet that reduce the risk of developing chronic diseases. β-Caryophyllene (CAR) is a common constituent of the essential oil of numerous plants, vegetables, fruits and medicinal herbs, and has been used as a flavouring agent since the 1930 s. Here, we report the antioxidant activity of CAR, its protective effect on liver fibrosis and its inhibitory capacity on hepatic stellate cell (HSC) activation. CAR was tested for the inhibition of lipid peroxidation and as a free radical scavenger. CAR had higher inhibitory capacity on lipid peroxidation than probucol, α-humulene and α-tocopherol. Also, CAR showed high scavenging activities against hydroxyl radical and superoxide anion. The activity of 5-lipoxygenase, an enzyme that actively participates in fibrogenesis, was significantly inhibited by CAR. Carbon tetrachloride-treated rats received CAR at 2, 20 and 200 mg/kg. CAR significantly improved liver structure, and reduced fibrosis and the expression of Col1a1, Tgfb1 and Timp1 genes. Oxidative stress was used to establish a model of HSC activation with overproduction of extracellular matrix proteins. CAR (1 and 10 μm) increased cell viability and significantly reduced the expression of fibrotic marker genes. CAR, a sesquiterpene present in numerous plants and foods, is as a natural antioxidant that reduces carbon tetrachloride-mediated liver fibrosis and inhibits hepatic cell activation.

Evaluation of a chemiluminescent enzyme-linked immunosorbent assay for the diagnosis of Trypanosoma cruzi infection in a nonendemic setting

The disappearance of lytic, protective antibodies (Abs) from the serum of patients with Chagas disease is accepted as a reliable indicator of parasitological cure. The efficiency of a chemiluminescent enzyme-linked immunosorbent assay based on a purified, trypomastigote-derived glycosylphosphatidylinositol-anchored mucin antigen for the serologic detection of lytic Abs against Trypanosoma cruzi was evaluated in a nonendemic setting using a panel of 92 positive and 58 negative human sera. The technique proved to be highly sensitive {100%; 95% confidence interval (CI) = 96-100} and specific (98.3%; 95% CI = 90.7-99.7), with a kappa score of 0.99. Therefore, this assay can be used to detect active T. cruzi infection and to monitor trypanosomicidal treatment.

Long-term efficacy and safety of atazanavir/ritonavir treatment in a cohort of treatment-naïve HIV patients: An interim analysis of the REMAIN study.

Purpose: Combined antiretroviral therapy has dramatically improved HIV-infected individuals survival. Long-term strategies are currently needed to achieve the goal of durable virologic suppression. However, long-term available data for specific antiretrovirals (ARV) are limited. In clinical trials, boosted atazanavir (ATV/r) regimens has shown good efficacy and tolerability in ARV-naïve patients for up to 4 years. The REMAIN study aimed to evaluate the long-term outcomes of ATV/r regimens in ARV-naïve patients in a real life setting. Methods: Non-comparative, observational study conducted in Germany, Portugal and Spain. Historical and longitudinal follow-up data was extracted six monthly from the medical record of HIV-infected, treatment-naïve patients, who initiated an ATV/r-regimen between 2008 and 2010. The primary endpoint was the proportion of patients remaining on ATV treatment over time. Secondary endpoints included virologic response (HIV-1 RNA <50 c/mL and <500 c/mL), reasons for discontinuation and long-term safety. The duration of treatment and time to virologic failure (VF) were analyzed using the Kaplan- Meier method. Data from an interim analysis including patients with at least one year of follow-up are reported here. Results: A total of 411 patients were included in this interim analysis [median (Q1, Q3) follow-up: 23.42 (16.25, 32.24) months≥: 77% male; median age 40 years [min, max: 19, 78≥; 16% IDUs; 18% CDC C; 18% hepatitis C. TDF/FTC was the most common backbone (85%). At baseline, median (Q1, Q3) HIV-RNA and CD4 cell count were 4.91 (4.34, 5.34) log10 c/mL and 256 (139, 353) cells/mm3, respectively. The probability of remaining on treatment was 0.84 (95% CI: 0.80, 0.87) and 0.72 (95% CI: 0.67, 0.76) for the first and second year, respectively. After 2 years of follow-up, 84% (95% CI: 0.79, 0.88) of patients were virologically suppressed (<50 c/mL). No major protease inhibitors mutations were observed at VF. Overall, 125 patients (30%) discontinued ATV therapy [median (Q1, Q3) time to discontinuation: 11.14 (6.24, 19.35) months]. Adverse events (AEs) were the main reason for discontinuation (n =47, 11%). Hyperbilirubinaemia was the most common AE leading to discontinuation (14 patients). No unexpected AEs were reported. Conclusions: In a real life clinical setting, ATV/r regimens showed durable virologic efficacy with good tolerability in an ARV-naïve population. Data from longer follow-up will provide additional valuable information.

Megazol and its bioisostere 4H-1,2,4-triazole: comparing the trypanocidal, cytotoxic and genotoxic activities and their in vitro and in silico interactions with the Trypanosoma brucei nitroreductase enzyme

Megazol (7) is a 5-nitroimidazole that is highly active against Trypanosoma cruzi and Trypanosoma brucei, as well as drug-resistant forms of trypanosomiasis. Compound 7 is not used clinically due to its mutagenic and genotoxic properties, but has been largely used as a lead compound. Here, we compared the activity of 7 with its 4H-1,2,4-triazole bioisostere (8) in bloodstream forms of T. brucei and T. cruzi and evaluated their activation by T. brucei type I nitroreductase (TbNTR) enzyme. We also analysed the cytotoxic and genotoxic effects of these compounds in whole human blood using Comet and fluorescein diacetate/ethidium bromide assays. Although the only difference between 7 and 8 is the substitution of sulphur (in the thiadiazole in 7) for nitrogen (in the triazole in 8), the results indicated that 8 had poorer antiparasitic activity than 7 and was not genotoxic, whereas 7 presented this effect. The determination of Vmax indicated that although 8 was metabolised more rapidly than 7, it bounds to the TbNTR with better affinity, resulting in equivalent kcat/KM values. Docking assays of 7 and 8 performed within the active site of a homology model of the TbNTR indicating that 8 had greater affinity than 7.

A neuron-specific deletion of the microRNA-processing enzyme DICER induces severe but transient obesity in mice.

MicroRNAs (miRNAs) are small, non-coding RNA molecules that regulate gene expression post-transcriptionally. MiRNAs are implicated in various biological processes associated with obesity, including adipocyte differentiation and lipid metabolism. We used a neuronal-specific inhibition of miRNA maturation in adult mice to study the consequences of miRNA loss on obesity development. Camk2a-CreERT2 (Cre+) and floxed Dicer (Dicerlox/lox) mice were crossed to generate tamoxifen-inducible conditional Dicer knockouts (cKO). Vehicle- and/or tamoxifen-injected Cre+;Dicerlox/lox and Cre+;Dicer+/+ served as controls. Four cohorts were used to a) measure body composition, b) follow food intake and body weight dynamics, c) evaluate basal metabolism and effects of food deprivation, and d) assess the brain transcriptome consequences of miRNA loss. cKO mice developed severe obesity and gained 18 g extra weight over the 5 weeks following tamoxifen injection, mainly due to increased fat mass. This phenotype was highly reproducible and observed in all 38 cKO mice recorded and in none of the controls, excluding possible effects of tamoxifen or the non-induced transgene. Development of obesity was concomitant with hyperphagia, increased food efficiency, and decreased activity. Surprisingly, after reaching maximum body weight, obese cKO mice spontaneously started losing weight as rapidly as it was gained. Weight loss was accompanied by lowered O2-consumption and respiratory-exchange ratio. Brain transcriptome analyses in obese mice identified several obesity-related pathways (e.g. leptin, somatostatin, and nemo-like kinase signaling), as well as genes involved in feeding and appetite (e.g. Pmch, Neurotensin) and in metabolism (e.g. Bmp4, Bmp7, Ptger1, Cox7a1). A gene cluster with anti-correlated expression in the cerebral cortex of post-obese compared to obese mice was enriched for synaptic plasticity pathways. While other studies have identified a role for miRNAs in obesity, we here present a unique model that allows for the study of processes involved in reversing obesity. Moreover, our study identified the cortex as a brain area important for body weight homeostasis.

Living with digestive stomas: strategies to cope with the new bodily reality.

OBJECTIVE the objective in this study was to describe the strategies developed by digestive stoma patients to cope with their situation. METHOD a qualitative and descriptive study was undertaken, involving 21 stoma patients living in the provinces of Málaga and Granada (Spain). The informants were selected in accordance with criteria of appropriateness and diversity, through intentional sampling. The data were collected by means of semistructured interviews. RESULTS the content analysis revealed three categories around which the distinct strategies were developed: Self-care, Adaptation to the bodily change and Self-help. CONCLUSION the strategies developed are focusing on achieving the effective management of the stoma and are closely linked with the achievement of autonomy. Discovering the strategies applied is fundamental for the nursing professionals to offer high-quality care, centered on people and their process.

Evaluation of a recombinant rhoptry protein 2 enzyme-linked immunoassay for the diagnosis of toxoplasmosis acquired during pregnancy

The aim of this study was to evaluate an enzyme-linked immunoassay with recombinant rhoptry protein 2 (ELISA-rROP2) for its ability to detectToxoplasma gondii ROP2-specific IgG in samples from pregnant women. The study included 236 samples that were divided into groups according to serological screening profiles for toxoplasmosis: unexposed (n = 65), probable acute infection (n = 48), possible acute infection (n = 58) and exposed to the parasite (n = 65). When an indirect immunofluorescence assay forT. gondii-specific IgG was considered as a reference test, the ELISA-rROP2 had a sensitivity of 61.8%, specificity of 62.8%, predictive positive value of 76.6% and predictive negative value of 45.4% (p = 0.0002). The ELISA-rROP2 reacted with 62.5% of the samples from pregnant women with probable acute infection and 40% of the samples from pregnant women with previous exposure (p = 0.0180). Seropositivity was observed in 50/57 (87.7%) pregnant women with possible infection. The results underscored that T. gondii rROP2 is recognised by specific IgG antibodies in both the acute and chronic phases of toxoplasmosis acquired during pregnancy. However, the sensitivity of the ELISA-rROP2 was higher in the pregnant women with probable and possible acute infections and IgM reactivity.

Gender difference in the response to an angiotensin-converting enzyme inhibitor and a diuretic in hypertensive patients of African descent.

BACKGROUND: The efficacy of angiotensin-converting enzyme (ACE) inhibitors in decreasing blood pressure in African patients is controversial. OBJECTIVE: We examined the ambulatory blood pressure (ABP) response to a diuretic and an ACE inhibitor in hypertensive patients of East African descent and evaluated the individual characteristics that determined treatment efficacy. DESIGN: A single-blind randomized AB/BA crossover design. SETTING: Hypertensive families of East African descent from the general population in the Seychelles. PARTICIPANTS: Fifty-two (29 men and 23 women) out of 62 eligible hypertensive patients were included.Main outcome measures ABP response to 20 mg lisinopril (LIS) daily and 25 mg hydrochlorothiazide (HCT) daily given for a 4-week period.Results The daytime systolic/diastolic ABP response to HCT was 4.9 [95% confidence interval (CI) 1.2-8.6]/3.6 (1.0-6.2) mmHg for men and 12.9 (9.2-16.6)/6.3 (3.7-8.8) mmHg for women. With LIS the response was 18.8 (15.0-22.5)/14.6 (12.0-17.1) mmHg for men and 12.4 (8.7-16.2)/7.7 (5.1-10.2) mmHg for women. The night-time systolic/diastolic response to HCT was 5.0 (0.6-9.4)/2.7 [(-0.4)-5.7] mmHg for men and 11.5 (7.1-16.0)/5.7 (2.6-8.8) mmHg for women, and to LIS was 18.7 (14.2-22.1)/15.4 (12.4-18.5) mmHg for men and 3.5 [(-1.0)-7.9]/2.3 [(-0.8)-5.4] mmHg for women. Linear regression analyses showed that gender is an independent predictor of the ABP responses to HCT and to LIS. CONCLUSIONS: Hypertensive patients of African descent responded better to LIS than to HCT. Men responded better to LIS than to HCT and women responded similarly to both drugs.

Commercial enzyme-linked immunosorbent assay versuspolymerase chain reaction for the diagnosis of chronic Chagas disease: a systematic review and meta-analysis

Chronic Chagas disease diagnosis relies on laboratory tests due to its clinical characteristics. The aim of this research was to review commercial enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) diagnostic test performance. Performance of commercial ELISA or PCR for the diagnosis of chronic Chagas disease were systematically searched in PubMed, Scopus, Embase, ISI Web, and LILACS through the bibliography from 1980-2014 and by contact with the manufacturers. The risk of bias was assessed with QUADAS-2. Heterogeneity was estimated with the I2 statistic. Accuracies provided by the manufacturers usually overestimate the accuracy provided by academia. The risk of bias is high in most tests and in most QUADAS dimensions. Heterogeneity is high in either sensitivity, specificity, or both. The evidence regarding commercial ELISA and ELISA-rec sensitivity and specificity indicates that there is overestimation. The current recommendation to use two simultaneous serological tests can be supported by the risk of bias analysis and the amount of heterogeneity but not by the observed accuracies. The usefulness of PCR tests are debatable and health care providers should not order them on a routine basis. PCR may be used in selected cases due to its potential to detect seronegative subjects.

Maladie de Fabry: du diagnostic a l'enzymotherapie substitutive. [Fabry disease: diagnostic due of substitutive enzyme-therapy]

Fabry disease is a X-linked sphingolipid storage disorder resulting from the defective activity of the lysosomal enzyme, alpha-galactosidase A. Hemizygotes develop severe multisystemic disease, dominated by renal failure and progressive neurological and cardiac involvement, causing premature death. Thirty percent of heterozygotes have severe involvement of one or several organs. With developments in molecular biology, it is now possible to produce the human recombinant enzyme alpha-galactosidase A. More than 20 patients are now treated in Switzerland.

Kalemia during combined therapy with an angiotensin converting enzyme inhibitor and a potassium-sparing diuretic.

Both angiotensin converting enzyme (ACE) inhibitors and potassium-sparing diuretics tend to increase serum potassium levels. This retrospective study was undertaken to assess whether these two types of agents can nevertheless be combined safely. Twelve hypertensive patients were treated for 1-70 months (mean = 17) with an ACE inhibitor together with a potassium-sparing diuretic (spironolactone, n = 10; amiloride, n = 2). In addition, eight patients also took a thiazide or a loop diuretic. Nine patients had a normal and three a slightly impaired renal function. No clinically relevant hyperkalemia was observed during the course of the study. These data suggest that it is not impossible to combine an ACE inhibitor with a potassium-sparing diuretic, as long as renal function is normal and serum potassium concentration is monitored closely.

Role of bradykinin in the neonatal renal effects of angiotensin converting enzyme inhibition.

The vascular effects of angiotensin converting enzyme inhibitors are mediated by the inhibition of the dual action of angiotensin converting enzyme (ACE): production of angiotensin II and degradation of bradykinin. The deleterious effect of converting enzyme inhibitors (CEI) on neonatal renal function have been ascribed to the elevated activity of the renin-angiotensin system. In order to clarify the role of bradykinin in the CEI-induced renal dysfunction of the newborn, the effect of perindoprilat was investigated in anesthetized newborn rabbits with intact or inhibited bradykinin B2 receptors. Inulin and PAH clearances were used as indices of GFR and renal plasma flow, respectively. Perindoprilat (20 microg/kg i.v.) caused marked systemic and renal vasodilation, reflected by a fall in blood pressure and renal vascular resistance. GFR decreased, while urine flow rate did not change. Prior inhibition of the B2 receptors by Hoe 140 (300 microg/kg s.c.) did not prevent any of the hemodynamic changes caused by perindoprilat, indicating that bradykinin accumulation does not contribute to the CEI-induced neonatal renal effects. A control group receiving only Hoe 140 revealed that BK maintains postglomerular vasodilation via B2 receptors in basal conditions. Thus, the absence of functional B2 receptors in the newborn was not responsible for the failure of Hoe 140 to prevent the perindoprilat-induced changes. Species- and/or age-related differences in the kinin-metabolism could explain these results, suggesting that in the newborn rabbit other kininases than ACE are mainly responsible for the degradation of bradykinin.