Endothelial Function and Serum Concentration of Toxic Metals in Frequent Consumers of Fish

Background

Endothelial dysfunction is involved in the pathogenesis of atherosclerosis. Consumption of fish is associated with reduced cardiovascular risk, but there is paucity of data concerning its effect on endothelial function. Furthermore, investigation of the effects of fish consumption on health must take into account the ingestion of contaminants, including transition metals and some metalloids, which may have unfavorable effects on health, including those on the cardiovascular system. We investigated the association between fish consumption, endothelial function (flow mediated dilation of the brachial artery), and serum concentration of some toxic metals in apparently healthy people.

Methods

Twenty-nine high fish consumers (at least 3 portions a week) were compared with 25 low fish consumers (less than 1 portion a week). All participants were free of diabetes, cardiovascular or other systemic diseases. Serum metal (antimonium, arsenic, mercury, lead, cobalt, copper, zinc, selenium, strontium) concentrations were measured in subgroups of 24 high fish consumers and 19 low fish consumers.

Results

Both groups exhibited similar habitual dietary patterns, age and anthropometric characteristics. The high fish consumers had higher flow mediated dilation (9.7±1.8 vs. 7.3±1.9%; P<0.001), but also higher serum concentrations of mercury (5.87±2.69 vs. 1.65±1.10 mcg/L; P<0.001) and arsenic (6.04±3.25 vs. 2.30±1.58 mcg/L; P<0.001). The fasting plasma glucose concentrations were significantly correlated with both mercury (r = 0.39; P = 0.01) and arsenic concentrations (r = 0.55; P<0.001).

Conclusions

Habitual consumption of high amounts of fish is associated with better endothelial function despite higher serum concentrations of mercury and arsenic.     

Impact of precipitation dynamics on net ecosystem productivity

Net ecosystem productivity (NEP) was measured on shortgrass steppe (SGS) vegetation at the USDA Central Plains Experimental Range in northeastern Colorado from 2001 to 2003. Large year‐to‐year differences were observed in annual NEP, with >95% of the net carbon uptake occurring during May and June. Low precipitation during the 2002 April to June time period greatly reduced annual net carbon uptake. Large precipitation events (>10 mm day^?1) promoted carbon uptake, while small precipitation events (<10 mm day^?1) enhanced heterotrophic respiration and resulted in a net loss of carbon from the system. Large precipitation event enhanced carbon uptake was attributed to increased soil water content (SWC), which promotes plant photosynthesis. The large precipitation events which occurred from July to October have lower increases in daytime net CO₂ uptake (NEP_d) due to the presence of low live plant biomass compared to earlier in the growing season. Live aboveground plant biomass (AGB), solar radiation, and SWC were the major variables that controlled NEP_d, while AGB, SWC, and relative humidity control nighttime respiration losses (NEP_n). Aboveground plant biomass is the most important variable for controlling both NEP_d and NEP_n dynamics. These results suggest that the major factor controlling growing season NEP_n is the amount of carbon fixed via photosynthesis during the day. Heterotrophic soil respiration is greatly enhanced for one to 2 days following rainfall events with daily rainfall events >5 mm having a similar increase in respiration (>3.00 g m Cm^?2 day^?1). In addition, the size of the heterotrophic respiration pulse is independent of both the amount of time since the last rainfall event and the time of occurrence during the growing season.     

Fluorescent labeling of proteins in sodium dodecyl sulfate complexes with fluorescamine

The effects of sodium dodecyl sulfate on the fluorescent labeling of proteins were studied. Of 57 primary amine groups in bovine serum albumin, no more than 7 are titrable by fluorescamine. Fluorescamine labeling does not cause appreciable conformational changes of proteins. The extent of labeling of proteins decreases as the concentrations of sodium dodecyl sulfate increases. The fluorescence properties of labeled primary amine are only slightly affected by the polarities of the solvents. The inhibitory effects of sodium dodecyl sulfate upon labelings are interpreted as the low permeability of fluorescamine toward the highly charged envelopes of sodium dodecyl sulfate-protein micelles.     

Evolutionary and clinical neocentromeres: two faces of the same coin?

It has been hypothesized that human clinical neocentromeres and evolutionary novel centromeres (ENC) represent two faces of the same phenomenon. However, there are only two reports of loci harboring both a novel centromere and a clinical neocentromere. We suggest that only the tip of the iceberg has been scratched because most neocentromerization events have a very low chance of being observed. In support of this view, we report here on a neocentromere at 9q33.1 that emerged in a ring chromosome of about 12 Mb. The ring was produced by a balanced rearrangement that was fortuitously discovered because of its malsegregation in the propositus. Chromatin-immunoprecipitation-on-chip experiments using anti-centromere protein (CENP)-A and anti-CENP-C antibodies strongly indicated that a novel centromeric domain was present in the ring, in a chromosomal domain where an ENC emerged in the ancestor to Old World monkeys.     

Quercus ilex L.: How season,Plant Organ and Extraction Procedure Can Influence Chemistry and Bioactivities

Quercus species have a plethora of applications, either in wine and wood industries, in human and animal nutrition or in human health. In order to improve the knowledge on this genus, the aim of the present study was to correlate, for the first time, the phenolic composition of different Quercus ilex L. plant tissues (leaves in two maturation stages, acorns, teguments and cotyledons) and different extraction procedures with scavenging and anticholinesterase activities. The hydromethanolic and aqueous extracts obtained showed strong radical scavenging activity against DPPH, superoxide anion radical and nitric oxide radical, leaves exhibiting higher total phenolic content and revealing the best antioxidant properties, followed by tegument and acorns. Concerning the phenolic profile, fifteen compounds were identified and quantified by HPLC‐DAD, ranging from 1568.43 to 45,803.16 mg/kg dried extract. The results indicate that Q. ilex can be a source of strong antioxidant phenolic compounds with possible interest for food and pharmaceutical industries.     

Balance between autocrine interleukin-1beta and caspases defines life versus death of polymorphonuclear cells

The role of endogenous IL-1beta in regulating spontaneous and Fas-triggered apoptosis of human PMN has been studied in relation to the activity of the IL-1beta-generating enzyme ICE (caspase-1), an enzyme also involved in the mechanism of cell death. Upon in vitro culture, PMN undergo spontaneous apoptosis and express increasing levels of IL-1beta, caspase-1- and caspase-3-like enzymes. Endogenous IL-1beta protects PMN from apoptosis, since inhibition of either IL-1beta or caspase-1 activity can accelerate PMN apoptotic death. Thus, in spontaneous PMN apoptosis caspase-1 essentially plays an anti-apoptotic role by inducing maturation of protective IL-1beta, whereas other molecules are responsible of driving apoptosis. Upon Fas triggering, PMN apoptosis is greatly accelerated, in correlation with increased caspase activity, whereas IL-1beta production is not augmented. Inhibition of IL-1beta activity can increase Fas-induced apoptosis, whereas caspase-1 inhibitors are without significant effect. It is hypothesized that in Fas-induced PMN apoptosis caspase-1 has a double role: it can protect from apoptosis through generation of protective IL-1beta, as in spontaneous apoptosis, and it can also exert pro-apoptotic activity which counterbalances the protective effect and allows accelerated apoptosis.     

Fine needle aspiration biopsy of a posttransplant lymphoproliferative disorder with pronounced plasmacytic differentiation presenting in the face. A case report

BACKGROUND: Posttransplant lymphoproliferative disorders (PTLDs) occur in fewer than 2% of transplant patients. However, as a group, 54% of PTLD patients die of these diseases. Presentation as only skin/superficial soft tissue nodules is rare, with this the second such reported case, and this is the only fine needle aspiration biopsy (FNAB) of such a case as well as the only FNAB of a plasmacytoid monomorphous/monoclonal PTLD. CASE: A 48-year-old, white male, seven years status post kidney transplantation, presented with a 2.5-cm mass in the skin/soft tissue anterior to the right maxillary sinus. FNAB showed a moderately cellular smear composed of discohesive cells, many with the morphology of plasma cells and some with the morphology of large lymphocytes. Flow cytometry showed these cells to be a monoclonal B-cell population, and a diagnosis of monomorphous/monoclonal PTLD was made. The diagnosis was subsequently confirmed by histology. The patient ultimately died. CONCLUSION: The clinical course of the present patient was grave as compared with the course of the other reported patient.