Increased alpha suppression with age during involuntary memory retrieval

Recent work suggests that while voluntary episodic memory declines with age, involuntary episodic memory, which comes to mind spontaneously without intention, remains relatively intact. However, the neurophysiology underlying these differences has yet to be established. The current study used electroencephalography (EEG) to investigate voluntary and involuntary retrieval in older and younger adults. Participants first encoded sounds, half of which were paired with pictures, the other half unpaired. EEG was then recorded as they listened to the sounds, with participants in the involuntary group performing a sound localization cover task, and those in the voluntary group additionally attempting to recall the associated pictures. Participants later reported which sounds brought the paired picture to mind during the localization task. Reaction times on the localization task were slower for voluntary than involuntary retrieval and for paired than unpaired sounds, possibly reflecting increased attentional demands of voluntary retrieval and interference from reactivation of the associated pictures respectively. For the EEG analyses, young adults showed greater alpha event-related desynchronization (ERD) during voluntary than involuntary retrieval at frontal and occipital sites, while older adults showed pronounced alpha ERD regardless of intention. Additionally, older adults showed greater ERD for paired than unpaired sounds at occipital sites, likely reflecting visual reactivation of the associated pictures. Young adults did not show this alpha ERD memory effect. Taken together, these data suggest that involuntary memory is largely preserved with age, but this may be due to older adults' greater recruitment of top-down control even when demand for such control is limited.     

Unconjugated hyperbilirubinaemia in HBV carriers. Discriminant value of nicotinic acid (NA) test

Recently an unconjugated hyperbilirubinaemia, without any other abnormalities in liver function test, in 14.3% of HBV Japanese carriers has been noticed. Therefore, it would be possible to argue that the persistent infection of HBV in hepatocytes might play a role in an hypothetical metabolic derangement of bilirubin clearance. Twenty-five subjects in a group of 468 HBsAg+ patients (equal to 5.33%) presented an hyperbilirubinaemia. This percentage was not different from the 5.83% found in 3083 HBsAg- controls coming from the same institution. Therefore we could exclude that in our population the presence of HBV surface antigen itself would determine a statistically higher level of total bilirubin (TB) than in controls. The nicotinic acid (NA) loading test may reveal some bilirubin metabolic defects (i.e. Gilbert syndrome), even in subjects with normal basal values of TB. According to this background, we performed in 11 HBsAg+ males with basal TB higher than 17.1 mumol/l (1 mg%) (group A/1), 13 HBsAg+ males with basal TB lower or equal to 17.1 mumol/l (group A/2) and 14 HBsAg- normal controls matched for sex and age (group B) the NA test according to R?llinghoff et al. All the parameters calculated by the NA test resulted significantly different in the A/1 group compared with the B group, but not different from those found by several authors in the Gilbert's syndrome. On the contrary, no significant differences have been noticed between the latter group and the A/2 group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Sesquiterpene Lactones in the Molluscidal Extract of Eremanthus glomerulatus

The eremantholides 1A, 1B, 1E, 1G, 1H, 1J and the germacranolides 2A, B were found in the molluscidal extract from EREMANTHUS GLOMERULATUS L.     

Glaucolide B, A Molluscicidal Sesquiterpene Lactone, and Other Constituents of Vernonia eremophila

The sesquiterpene lactone glaucolide B was isolated from the molluscicidal extract of VERNONIA EREMOPHILA Mart, and shown to be responsible for the molluscicidal activity. Hydrogenolysis of glaucolide B resulted in the disappearance of the activity. Other inactive constituents of the extract were 3,7-dimethoxy-5,3',4'-trihydroxyflavone and two transformation products, possibly artefacts, of glaucolide B. Glaucolide B exhibited strong antimicrobial activity against B, CEREUS and moderate activity against S. AURENS, but was inactive in several other systems.     

Anodontites trapesialis: A biological monitor of organochlorine pesticides

The mussel Anodontites trapesialis (Lam, 1819) was used as an indicator of organochlorine pollutants in the Pardo River, located in the municipality of Ribeirão Preto (21° 07S and 47° 45W), State of São Paulo, Brazil.Biological monitoring was performed for one year at the site of a sugar cane grove on the left bank of the river. Forty-three animals were placed in two aluminum enclosures on the river bottom at this site and 4 animals of each enclosure were sacrificed for pesticide analysis at 3-month intervals, each collection corresponding to one season of the year.The animals were found to have been exposed to DDT, lindane, heptachlor, aldrin and dieldrin. Endrin was not detected in any of the analyses.Research supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP).     

A new approach to the diagnosis of central venous catheter sepsis

One hundred forty-four cancer patients harboring a central venous catheter (CVC) were prospectively investigated to assess the relationship between hub culture, clinical assessment of sepsis before removal, and CVC sepsis. In 22 patients, the CVC was removed because of clinical assessment of catheter sepsis expressed by the staff prior to the removal. For each CVC removal, peripheral blood (qualitative method), hub, and CVC tip (quantitative method) cultures were performed. Clinical sepsis (disappearance of fever after CVC removal) was observed in 13 patients, microbiologic "sepsis" (identification of the same microorganisms on the CVC tip and in the peripheral blood) in seven patients, and clinical and/or microbiologic sepsis in 16 patients. Staphylococcus epidermidis was the microorganism most frequently identified. Hub culture was negative in 48% and positive for a low number and a high number of colonies in 35% and 17%, respectively. The predictive value of hub culture was 96% when testing negative and 8% and 37% (p = 3 x 10(-3)) when testing positive for a low and a high number of colonies, respectively. Predictive values of clinical assessment were 55% if positive and 97% if negative. Combining hub cultures and clinical assessment, the risk of sepsis varied from 2% with both evaluations negative to 89% in the case of positive clinical assessment associated with positive high-count hub. Inasmuch as the CVCs used have a disposable hub, it is possible to have an accurate diagnosis of CVC sepsis without removing the CVC.     

Downregulation of inflammatory markers by conjugated linoleic acid isomers in human cultured astrocytes

Objectives: Conjugated linoleic acid (CLA) isomers have been shown to possess anti-inflammatory activity in the central nervous system. In this study, we aimed to evaluate whether modulation of the fatty acid profile by the CLA isomers c9,t11 or t10,c12CLA was associated with changes in the expression of pro-inflammatory molecules in human astrocytes.

Methods: Cultured astrocytes were treated for 6 days with 100?µM fatty acids (c9,t11CLA or t10,c12CLA or oleic acid). Following the treatment, the fatty acid profile of the cell and pro-inflammatory molecule expression were assessed.

Results: Only the t10,c12CLA isomer induced a significant decrease in arachidonic acid and increased the ratio of docosahexaenoic acid/eicosapentaenoic acid, which constitutes indirect evidence of peroxisome proliferator-activated receptor alpha activation. Inhibition of tumour necrosis factor-α, interleukin-1β, and RANTES expression was observed in astrocytes treated with c9,t11CLA and t10,c12CLA.

Discussion: Current data demonstrate that CLA isomers, particularly t10,c12, may affect neuroinflammation by reducing the pro-inflammatory molecules in cultured astrocytes, suggesting a potential nutritional role of CLA isomers in modulating the astrocyte inflammatory response.     

Update on treatment in multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system. In recent years, many disease-modifying therapies (DMT) have been approved for MS treatment. For this reason, a profound knowledge of the characteristics and indications of the available compounds is required to tailor the therapeutic strategy to the individual patient characteristics. This should include the mechanism of action and pharmacokinetic of the drug, the safety and efficacy profile provided by clinical trials, as well as the understanding of possible side effects. Moreover, the evolving knowledge of the disease is paving the way to new and innovative therapeutic approaches, as well as the development of new biomarkers to monitor the therapeutic response and to guide the clinician's therapeutic choices. In this review we provide a comprehensive overview on currently approved therapies in MS and the emerging evidence-based strategies to adopt for initiating, monitoring, and eventually adapting a therapeutic regimen with DMT.