[Does Omega-3 supplementation after the age of 65 influence cognitive function? Results of a systematic review]

BACKGROUND

The percentage of the older population is progressively increasing as are diseases associated with aging such as cognitive decline (CD) and dementia. Observational epidemiological studies suggest that diets rich in omega 3 polyunsaturated fatty acids (w3-PUFA) might reduce the risk of CD and dementia. The main objective was to assess whether there is sufficient scientific evidence about the relationship between w3-PUFA supplementation in patients aged 65 or older and cognitive performance.

METHODS

We used the Pubmed data base to search for articles related to w3-PUFA and CD or dementia. Initially we identified 582 articles, after applying the eligibility criterion we included six studies in this systematic review.

RESULTS

The studies included were heterogeneous regarding population, measurement of exposure and outcome. Therefore, it was not possible to conduct a quantitative analysis. Two studies found that w3-PUFA supplementation decreased the risk of Alzheimer and improved cognitive performance. Two studies found an improvement in only one of the domains of cognitive performance (visual analogical classification and verbal fluency) and another two did not find any evidence of protection.

CONCLUSIONS

We found few studies to support or refute the evidence that w3-PUFA supplementation in patients aged 65 or older improves cognitive performance or prevents dementia.

High Blood Pressure States in Children, Adolescents, and Young Adults Associate Accelerated Vascular Aging, with a Higher Impact in Females' Arterial Properties

The aims of the study were to determine (1) whether the presence of High blood pressure (HBP) states in the youth associate a steeper rate of age-related change in arterial geometrical and wall properties with respect to subjects with no previous cardiovascular risk factor (CRF) exposure, (2) in which parameters and in what magnitude, and (3) the existence of a gender-related difference in the impact of this condition on arterial properties. 300 individuals (mean/range: 15/4-29 years; 133 females) were included. Two groups were assembled: (1) Reference: nonprevious exposure to traditional CRF and (2) HBP: subjects with arterial hypertension and/or elevated blood pressure (BP) levels during the study. Additionally, HBP subjects were separated in BP-related subgroups. Measured parameters were (1) central (aortic) arterial BP and aortic pulse wave analysis parameters, (2) carotid and femoral artery local (pressure-strain elastic modulus) and regional (pulse wave velocity; PWV) stiffness, and (3) arterial diameters and carotid intima-media thickness (CIMT). Age-related changes in these parameters (absolute values and z-scores) were explored by obtaining simple linear regression models for each group. HBP presented a steeper rate of change (accelerated vascular aging; VA) for most of the parameters assessed, mainly in central (aortic) hemodynamics. VA increased as the HBP level got higher. Both males' and females' aging rates were affected by this condition, but females presented a more marked relative age-related increase with HBP exposure. HBP states in the youth gradually associate accelerated VA, with a progressive hemodynamic-structural-functional onset of damage, with females presenting a more marked relative HBP-associated arterial repercussion.

Main results of strategic noise maps and action plans in Navarre (Spain)

According to Directive 2002/49, strategic noise maps and their correspondent action plans were carried out in the Autonomous Community of Navarre, Spain. Six strategic noise maps were produced for 120 km of major roads as well as a strategic noise map for the Agglomeration of the Region of Pamplona (ARP) with a population of 280,199 inhabitants. In the ARP, a total of 36,400 people (13.0 %) are exposed to Ln levels over 55 dBA and 42,300 people (15.1 %) are exposed to Lden levels over 65 dBA. With regard to major roads, a total of 3,900 people are exposed to Ln levels over 55 dBA and 2,400 people are exposed to Lden levels over 65 dBA. When designing action plans, different prioritisation criteria concerning rank-based effectiveness measures (mainly the amount of people benefitting from them) were taken into account.

Human papillomavirus type-16 (HPV-16) major transforming proteins functionally interact with interferon signaling mechanisms

Since the IFN system has been implicated in cell growth and differentiation control mechanisms, we evaluated the influence of the expression of HPV-16 E6 and E7 oncoproteins on IFN signaling by using cotransfection experiments. Both viral oncoproteins differentially interfered with the inducibility of IFN-beta promoter by Sendai virus. The activation by IFN-gamma of a GBP ISRE reporter was dramatically affected by both viral proteins suggesting a disruption of STATs/IRFs function. Further, the inducibility of 6-16 gene ISRE reporter by IFN-alpha was decreased to varying degrees by both viral oncoproteins, implying that ISGF3 function is also impaired. Taken together, these observations suggest that HPV-16 negatively interacts with cellular targets of the IFN system, and these interactions may be implicated in cellular transformation caused by HPVs and their refractory response to IFN treatment.

Are urban noise pollution levels decreasing?

The majority of acoustic impact studies developed over the last 50 years have used a similar acoustic parameter (L(eq), L(dn)) but the noise mapping methodology has been very uneven. The selection of the measurement points, the measurement periods, or the evaluation indices have not followed a unique criterion. Therefore, it is not possible to compare the sound pollution levels between different cities from those studies, at least in a rigorous sense. Even more, different studies carried out in the same city by different researchers during different years and using different methodologies are not conclusive whether the acoustic pollution increases or decreases. The present paper shows results, with statistical significance, about the evolution of the acoustic pollution obtained for two Spanish cities, Pamplona and Madrid. In both cases, it can be concluded that noise pollution decreases over time (P<0.01).

Strategic noise map of a major road carried out with two environmental prediction software packages

The main objective of this study is to analyze the differences found in the results of noise mapping using two of the most popular software techniques for the prediction of environmental noise. The location selected to conduct the comparative study is an area encompassed by the ring road that surrounds the city of Pamplona and on a grid, with a total of 6 x 10(5) points, approximately. In fact, and as the Environmental Noise Directive points out, it is a major road designated by a Member State (Spain). Configuration of the calculation parameters (discretization of the sources, ground absorption, reflection order, etc.) was as equivalent as possible as far as programs allow. In spite of that, a great number of differences appear in the findings. Although in 95.5% of the points the difference in the noise level calculated from the two programs was less than 3 dB, this general statistic result concealed some great differences. These are due to the various algorithms that programs implement to evaluate noise levels. Most differences pertain to highly screened receivers or remote ones. In the former, the algorithm of visibility is the main cause of such differences. In the latter, differences are mainly brought about by a different implementation of the propagation under homogeneous and favorable atmospheric conditions from both software systems.

Influence of close-up dry period protein supplementation on productive and reproductive performance of Holstein cows in their subsequent lactation

Holstein cows on a commercial dairy were assigned to close-up dry groups and offered an 11.7% crude protein (CP) ration based on corn silage, alfalfa cubes, oat hay, corn, and barley grain without (Control; C) or with (Supplemented; S) 0.8 kg/d per cow of a high CP supplement of SoyPass, distillers dried grains, ring dried blood meal, feather meal, and corn gluten meal. Heifers (C: 37, S: 44) and mature cows (C: 96, S: 81) were allocated to one of four groups based upon their time in the close-up groups (i.e., 1 to 4, 5 to 8, 9 to 12, and 13 to 19 d) within parity (i.e., heifers or mature) for statistical analysis. Full lactation means of all response parameters for cows confirmed to be pregnant that completed a lactation (i.e., lactating at 305 d in milk or dried off before 305 d in milk but not culled; C: 28, S: 23 for heifers and C: 48, S: 43 for mature cows) were analyzed by ANOVA. Lactation curves were evaluated by parallel curve analysis to assess differences in lactation curve shape, and curve separation, due to treatments. Protein supplementation had no impact on full-lactation milk or milk component yields of heifers, determined by ANOVA, although parallel curve analysis showed higher milk and milk protein yield with protein supplementation. As the number of days cows spent consuming their assigned close-up dry rations increased, heifers produced more milk, milk fat and milk protein, although the maximum yield for milk and milk protein occurred for those fed close-up rations for 9 to 12 d. For mature cows, neither time close up or close-up period protein supplementation influenced any mean response parameter, by ANOVA, although parallel curve analysis showed higher milk and protein yield for supplemented cows as time close up increased. Overall, results suggest the optimum close-up period length was 9 to 12 d, with a protein content intermediate between 11.7 and 14.4% of DM, for heifers. In contrast, results do not support any substantive benefit of a close up period, or protein contents above 11.7%, for mature cows.

Mapping of genetic deletions on the long arm of chromosome 22 in human pancreatic adenocarcinomas

The molecular mechanisms of carcinogenesis in pancreatic cancer are still poorly understood, although the inactivation of tumor suppressor genes at multiple loci is suspected. We investigated the loss of heterozygosity (LOH) on chromosome 22 in pancreatic cancer by means of a PCR-based microsatellite analysis of archival paraffin-embedded histological sections in order to better define deleted region(s) and to test whether the NF-2 gene is involved. Using a panel of thirteen markers that spanned the long arm of chromosome 22, loss of heterozygosity was identified for at least one locus in 37% of investigated pancreatic adenocarcinomas. These deletions are clustered into two separate areas of the chromosome 22--one proximal to the NF-2 gene and one distal. The NF-2 gene itself is not involved. These regions are likely locations of tumor suppressor genes that may contribute to the development of pancreatic cancer.

[Are all sedation scales equally useful for nursing assessment?]

The usefulness of three clinical scales for monitoring sedation in intensive care units was compared. The Ramsay scale, Cook modification of the Glasgow scale, and combined Ramsay-Cook scale were evaluated. Thirty-five patients with continuous intravenous sedation were monitored using all three clinical scales. The scores were collected simultaneosly with a two-observer method carried out by the nurse in charge of the patient and a second observer (nurse or physician). The three scales were considered valid and reproductible, with "good" agreement for the Ramsay scale and "very good" agreement for the Cook modified coma scale and the combined Ramsay-Cook scale. In conclusion, since the Cook modified Glasgow scale was the most reproducible, it is preferred for use in research and daily practice. The Ramsay scale is more subjective, but may be useful for daily nursing activities.

Role of dermal cells from normal and ultraviolet B-damaged skin in induction of contact hypersensitivity and tolerance

With conventional regimens for induction of contact hypersensitivity with highly reactive haptens, circumstantial evidence implicates both epidermal and dermal APC. However, similar applications of hapten to skin that has been treated with an acute, low dose UVB radiation protocol induce contact hypersensitivity only in certain genetically defined strains of mice, termed UVB-resistant. Moreover, mice that fail to acquire contact hypersensitivity when hapten is painted on UVB-exposed skin display hapten-specific tolerance. In the present study, dermal cell suspensions have been prepared from normal and UVB-exposed mouse skin as a means of identifying the cell(s) that: 1) provide APC function after UVB radiation in UVB-resistant mice; and 2) confer tolerance after UVB radiation in UVB-susceptible mice. The results confirm that the normal murine dermis contains Ia+ cells that, when hapten-derivatized in vitro and injected s.c. into naive, syngeneic mice, possess typical Ag-presenting function. Cells with similar function are retained in the dermis of UVB-resistant mice after exposure to UVB radiation, whereas dermal cells of UVB-exposed skin of UVB-susceptible mice display no ability to induce contact hypersensitivity. Instead, the latter dermal cells, when hapten-conjugated and injected s.c., induce tolerance. Thus, doses of UVB radiation that deplete the epidermis of Langerhans cells do not deplete the dermis of UVB-resistant mice of contact hypersensitivity-inducing APC, but do confer upon cells within the dermis of UVB-susceptible mice the capacity to induce unresponsiveness.

Role of dermal cells from normal and ultraviolet B-damaged skin in induction of contact hypersensitivity and tolerance

With conventional regimens for induction of contact hypersensitivity with highly reactive haptens, circumstantial evidence implicates both epidermal and dermal APC. However, similar applications of hapten to skin that has been treated with an acute, low dose UVB radiation protocol induce contact hypersensitivity only in certain genetically defined strains of mice, termed UVB-resistant. Moreover, mice that fail to acquire contact hypersensitivity when hapten is painted on UVB-exposed skin display hapten-specific tolerance. In the present study, dermal cell suspensions have been prepared from normal and UVB-exposed mouse skin as a means of identifying the cell(s) that: 1) provide APC function after UVB radiation in UVB-resistant mice; and 2) confer tolerance after UVB radiation in UVB-susceptible mice. The results confirm that the normal murine dermis contains Ia+ cells that, when hapten-derivatized in vitro and injected s.c. into naive, syngeneic mice, possess typical Ag-presenting function. Cells with similar function are retained in the dermis of UVB-resistant mice after exposure to UVB radiation, whereas dermal cells of UVB-exposed skin of UVB-susceptible mice display no ability to induce contact hypersensitivity. Instead, the latter dermal cells, when hapten-conjugated and injected s.c., induce tolerance. Thus, doses of UVB radiation that deplete the epidermis of Langerhans cells do not deplete the dermis of UVB-resistant mice of contact hypersensitivity-inducing APC, but do confer upon cells within the dermis of UVB-susceptible mice the capacity to induce unresponsiveness.

Molecular karyotype variation in Leishmania (Viannia) peruviana: indication of geographical populations in Peru distributed along a north-south cline

Forty-one Leishmania peruviana isolates were selected along a north-south transect which crossed areas endemic for uta in three different biogeographical regions in the Peruvian Andes. The isolates were analysed by molecular karyotyping and hybridization with three chromosome-derived DNA probes. All the isolates could be distinguished from L. braziliensis by their pLb-134 hybridization patterns. However, the patterns with the other probes (pLb-168 and -22) could be used to cluster the Peruvian isolates in discrete groups (karyodemes) which varied in their level of similarity with L. braziliensis. The geographical distribution of these karyodemes supports the hypothesis that eco-graphical isolation has contributed to the heterogeneity of L. peruviana.

Biochemical characterization of Leishmania (Viannia) braziliensis and Leishmania (Viannia) peruviana by isoenzyme electrophoresis

Leishmanial organisms isolated from 24 patients with Andean cutaneous leishmaniasis (uta) and from 7 with sylvatic leishmaniasis in both cutaneous and mucosal forms were characterized on the basis of their isoenzyme profiles for 13 enzymes using both cellulose acetate (CA) and thin-layer starch gel (TLS) electrophoretic techniques. Malate dehydrogenase (MDH) after electrophoresis on CA or TLS and mannose phosphate isomerase (MPI) on TLS were the only enzymes of 13 examined which discriminated between the organisms from patients with uta (L. (V.) peruviana) and those with sylvatic leishmaniasis (L. (V.) braziliensis). Mannose phosphate isomerase gave more clear-cut and reproducible discrimination than did MDH on either TLS or CA, and it is suggested that MPI is a reliable enzyme marker that can be used in routine TLS electrophoresis to distinguish between L. (V.) peruviana and L. (V). braziliensis.

The use of nonradioactive DNA probes for the characterization of Leishmania isolates from Peru

We describe conditions for dot blot DNA hybridization studies using biotinylated kDNA probes from Leishmania. The sensitivity and specificity attained with biotinylated or 32P-labeled probes were equivalent. The lower level of detection obtained was 100 parasites that were blotted on nitrocellulose paper and then treated with Proteinase K. Studies were performed with 112 Leishmania isolates from Andean (uta) and sylvatic mucocutaneous (espundia) patients and all were determined to belong to the Leishmania braziliensis complex.

Characterization of Leishmania species from Peru

Twenty-six isolates of Leishmania parasites of Peruvian origin were studied by isoenzyme electrophoresis of four marker enzymes (ASAT, ALAT, G6PD and GPI), kinetoplast DNA hybridization and monoclonal antibody binding and compared with marker strains of the New World organisms L. b. braziliensis, L. b. guyanensis, L. m. mexicana and L. m. amazonensis. 12 of the isolates studied were of Andean origin; 11 of these were isolated from patients with Andean cutaneous leishmaniasis. The organisms originating from the Peruvian Amazonian forest were isolated from patients with cutaneous (12 cases) or mucocutaneous (2 cases) leishmaniasis. One of the Andean isolates was obtained from an infected phlebotomine vector. 25 of the new isolates were identified as L. braziliensis ssp. according to the three techniques employed. The results of monoclonal antibody binding showed that 23 of the isolates were indistinguishable from L. b. braziliensis. Two isolates identified as L. braziliensis ssp. according to their isoenzyme profiles and k-DNA hybridization patterns could not be classified at the subspecies level. The isolate obtained from the phlebotomine vector could not be identified. No evidence of the existence of parasites of the L. mexicana complex in Peruvian territory was found in this study. The results obtained show a remarkable similarity between Leishmania of Andean origin and L. b. braziliensis.