Syntheses of All-Methylated Ellagitannin, Isorugosin B and Rugosin B

Ellagitannins possess a wide range of biological activities and remarkable structural diversity, which commonly include an axially chiral biaryl unit. This paper describes syntheses of all-methylated versions of isorugosin B and rugosin B, which are regioisomeric, ellagitannin-related compounds. The key features of these syntheses involve the construction of an axially chiral biaryl function on a sugar moiety through a Pd-catalyzed intramolecular biaryl coupling reaction, Bringmann’s atroposelective lactone opening reaction, and a two-step ester formation. This is the first synthetic approach for generating ellagitannins featuring a valoneoyl group

An evaluation of the classification process within grassalco’s gravity concentrating plant at maripaston, district para-suriname / Uma avaliação do processo de classificação dentro da planta de concentração gravitacional em maripaston, distrito para-suriname

In 2014 started the states mining company of the government, N.V. Grassalco a pilot mining operation at Maripaston using a gravity concentration plant to process the tailing of the small scale gold miners that consist of free and associated recoverable gold. This plant consists of a Hammer mill, four Centrifugal concentrators, a Hydro cyclone, a Ball mill, and a Shaking table in the gold room. This project was carried out to evaluate the classification process of the hydro cyclone in this gravity concentrating plant and for this evaluation the apex diameter and discharge type, percentage solid, and particle size distribution were taken into account. To study the performance of the Hydro cyclone, the feed, underflow, and overflow were sampled and analyzed. The results obtained showed that the d80 determined during this project was between 500 µm and 700 µm, while N.V. Grassalco applies a d80 size of 63 µm, and the sharpness of separation was between 0.5 and 1.1, while according to some researchers the sharpness of separation of a good classification process lies between 0.2 and 0.4. It was also observed that the discharge type of the underflow was roping. Based on these findings can be concluded that the Hydro cyclone did not perform well.

Prognostic value of coronary artery calcium score in symptomatic individuals: A meta-analysis of 34,000 subjects

Background: Coronary artery calcium (CAC) scanning has evolved into an important subclinical prediction method for cardiovascular diseases in asymptomatic subjects. However, the prognostic implication of CAC scanning in symptomatic individuals is less clear. Objectives: To assess the prognostic utility of CAC in predicting risk of major adverse cardiac events (MACE) in stable patients with suspected CAD. Methods: We did a systematic electronic literature search for studies presenting original data in CAC score, and reporting cardiovascular events in stable, symptomatic patients as primary outcome. Primary outcome of the meta-analysis was the occurrence of MACE, a composite of late coronary revascularization, hospitalization for unstable angina or heart failure, nonfatal myocardial infarction, and cardiac death or all-cause mortality. Using random effects models, we pooled relative risk ratios of CAC for MACE, and adjusted hazard ratios (HR) of the associations between different CAC strata (CAC 0–100,100–400, and ≥ 400, versus CAC = 0) and incident MACE. Results: We included 19 observational studies (n = 34,041). In total, 1601 events were analyzed, of which 158 in patients with CAC = 0. The pooled relative risk ratio was 5.71 (95%-CI: 3.98;8.19) for subjects with CAC > 0. The pooled estimate of adjusted HRs demonstrated increasing, positive associations, with the strongest association for CAC > 400 (HR: 4.88; 95%-CI: 2.44;9.27). Conclusions: This meta-analysis demonstrated that increased levels of CAC are strongly and independently associated with increased risk for MACE in stable, symptomatic patients with suspected CAD, showing increasing risk with greater CAC scores. Application of CAC scanning as a prediction method could be useful for a considerable number of such patients

Prognostic value of the coronary artery calcium score in suspected coronary artery disease: a study of 644 symptomatic patients

Aim: The long-term value of coronary artery calcium (CAC) scanning has not been studied extensively in symptomatic patients, but was evaluated by us in 644 consecutive patients referred for stable chest pain. Methods: We excluded patients with a history of cardiovascular disease and with a CAC score of zero. CAC scanning was done with a 16-row MDCT scanner. Endpoints were: (a) overall mortality, (b) mortality or non-fatal myocardial infarction and (c) the composite of mortality, myocardial infarction or coronary revascularisation. Revascularisations within 1 year following CAC scanning were not considered. Results: The mean age of the 320 women and 324 men was 63 years. Follow-up was over 8 years. There were 58 mortalities, while 22 patients suffered non-fatal myocardial infarction and 24 underwent coronary revascularisation, providing 104 combined endpoints. Cumulative 8‑year survival was 95% with CAC score 100 and 100 and ≥400 units was 2.6 [95% confidence interval (CI) 1.23–5.54], and 4.6 (95% CI 2.1–9.47) respectively. After correction for clinical risk factors, CAC score remained independently associated with increased risk of cardiac events. Conclusions: Risk increased with increasing CAC score. Patients with CAC >100 or ≥400 Agatston units were at increased risk of major adverse cardiac events and are eligible for preventive measures. CAC scanning provided incremental prognostic information to guide the choice of diagnostic and therapeutic options in many subjects evaluated for chest pain

How the serotonin transporter 5-HTTLPR polymorphism influences amygdala function: the roles of in vivo serotonin transporter expression and amygdala structure

The serotonin transporter-linked promoter region (5-HTTLPR) polymorphism of the serotonin transporter gene is associated with amygdala response during negative emotion. The aim of this study was to investigate whether this genotype effect on amygdala function is mediated by current serotonin transporter (5-HTT) levels or rather by genetically induced influences during neurodevelopment, shaping brain structure. A total of 54 healthy subjects underwent functional and structural magnetic resonance imaging, [11C]DASB positron emission tomography and 5-HTTLPR genotyping to analyze the interrelationships between amygdala activation during processing of unpleasant stimuli, 5-HTTLPR genotype, amygdala volumes and 5-HTT levels in the midbrain and in other brain regions. In line with previous research, carriers of the short allele (S) showed increased amygdala activation. Path analysis demonstrated that this genotype effect was not procured by current 5-HTT availability but by amygdala structure, with smaller amygdala volumes in the S than in the LL genotype, as well as smaller volumes being associated with increased amygdala activation. Our findings stress the role of genetic effects during neurodevelopment

Differential serotonin transport is linked to the rh5-HTTLPR in peripheral blood cells

The human serotonin transporter (SERT) gene possesses a 43-base pair (bp) insertion-deletion promoter polymorphism, the h5-HTTLPR. Genotype at this locus correlates with variation in anxiety-related personality traits and risk for major depressive disorder in many studies. Yet, the complex effects of the h5-HTTLPR, in combination with closely associated single-nucleotide polymorphisms (SNPs), continue to be debated. Moreover, although SERT is of high clinical significance, transporter function in vivo remains difficult to assess. Rhesus express a promoter polymorphism related to the h5-HTTLPR. The rh5-HTTLPR has been linked to differences in stress-related behavior and cognitive flexibility, although allelic variations in serotonin uptake have not been investigated. We studied the serotonin system as it relates to the 5-HTTLPR in rhesus peripheral blood cells. Sequencing of the rh5-HTTLPR revealed a 23-bp insertion, which is somewhat longer than originally reported. Consistent with previous reports, no SNPs in the rh5-HTTLPR and surrounding genomic regions were detected in the individuals studied. Reductions in serotonin uptake rates, cell surface SERT binding, and 5-hydroxyindoleacetic acid/serotonin ratios, but not SERT mRNA levels, were associated with the rh5-HTTLPR short allele. Thus, serotonin uptake rates are differentiable with respect to the 5-HTTLPR in an easily accessible native peripheral tissue. In light of these findings, we foresee that primary blood cells, in combination with high sensitivity functional measurements enabled by chronoamperometry, will be important for investigating alterations in serotonin uptake associated with genetic variability and antidepressant responsiveness in humans

Serotonin, genetic variability, behaviour, and psychiatric disorders - a review

Brain monoamines, and serotonin in particular, have repeatedly been shown to be linked to different psychiatric conditions such as depression, anxiety, antisocial behaviour, and dependence. Many studies have implicated genetic variability in the genes encoding monoamine oxidase A (MAOA) and the serotonin transporter (5HTT) in modulating susceptibility to these conditions. Paradoxically, the risk variants of these genes have been shown, in vitro, to increase levels of serotonin, although many of the conditions are associated with decreased levels of serotonin. Furthermore, in adult humans, and monkeys with orthologous genetic polymorphisms, there is no observable correlation between these functional genetic variants and the amount or activity of the corresponding proteins in the brain. These seemingly contradictory data might be explained if the association between serotonin and these behavioural and psychiatric conditions were mainly a consequence of events taking place during foetal and neonatal brain development. In this review we explore, based on recent research, the hypothesis that the dual role of serotonin as a neurotransmitter and a neurotrophic factor has a significant impact on behaviour and risk for neuropsychiatric disorders through altered development of limbic neurocircuitry involved in emotional processing, and development of the serotonergic neurons, during early brain development