Buccal dental microwear variability in extant African Hominoidea: taxonomy versus ecology

Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have been used to trace the dietary habits of fossil species, including primates and hominids. However, few studies have addressed the variability of this microwear. The abrasiveness of dietary components depends not only on the hardness of the particles ingested, but also on the presence of dust and other exogenous elements introduced during food processing. These elements are responsible for the microwear typology observed on the enamel surfaces of primate teeth. Here we analyzed the variability of buccal microwear patterns in African Great Apes (Gorilla gorilla and Pan troglodytes), using tooth molds obtained from the original specimens held in several osteological collections. Our results suggest that ecological adaptations at subspecies or population level account for differences in microwear patterns, which are attributed to habitat and ecological conditions within populations rather than differences between species. The findings from studies on the variability of buccal dental microwear in extant species will contribute to a better understanding of extinct hominids’ diet and ecology.     

Patterns of genetic diversity and linkage disequilibrium in a highly structured Hordeum vulgare association-mapping population for the Mediterranean basin

Population structure and genome-wide linkage disequilibrium (LD) were investigated in 192 Hordeum vulgare accessions providing a comprehensive coverage of past and present barley breeding in the Mediterranean basin, using 50 nuclear microsatellite and 1,130 DArT^® markers. Both clustering and principal coordinate analyses clearly sub-divided the sample into five distinct groups centred on key ancestors and regions of origin of the germplasm. For given genetic distances, large variation in LD values was observed, ranging from closely linked markers completely at equilibrium to marker pairs at 50 cM separation still showing significant LD. Mean LD values across the whole population sample decayed below r ² of 0.15 after 3.2 cM. By assaying 1,130 genome-wide DArT^® markers, we demonstrated that, after accounting for population substructure, current genome coverage of 1 marker per 1.5 cM except for chromosome 4H with 1 marker per 3.62 cM is sufficient for whole genome association scans. We show, by identifying associations with powdery mildew that map in genomic regions known to have resistance loci, that associations can be detected in strongly stratified samples provided population structure is effectively controlled in the analysis. The population we describe is, therefore, shown to be a valuable resource, which can be used in basic and applied research in barley.     

The bioeroded megasurface of Oura (Algarve,south Portugal): implications for the Neogene stratigraphy and tectonic evolution of southwest Iberia

The use of rocky palaeoshore bioerosion analysis as a tool to solve stratigraphic and tectonic issues is beginning to bear fruits. The occurrence of an extensive intra-Miocene marine abrasion platform in southern Portugal at Oura (Albufeira) has been identified on the basis of bioerosion trace fossils analysis. The observed ichnodiversity is rather low, with bivalve boring Gastrochaenolites being dominant. Nevertheless, the ichnoassemblage may be assigned to the Entobia ichnofacies. The palaeoichnological study of the Oura hardground confirmed the existence of an important intra-Miocene stratigraphic gap (ca. 3 Ma hiatus), represented by a razor-sharp erosional contact that separates the two main Neogene units in the Algarvian region: the lower carbonate sequence of Lagos–Portimão Formation (Langhian/Serravallian) and the upper siliciclastic sequence of the Cacela Formation (Upper Tortonian).     

Compartments in a marine food web associated with phylogeny, body mass, and habitat structure

A long-standing question in community ecology is whether food webs are organized in compartments, where species within the same compartment interact frequently among themselves, but show fewer interactions with species from other compartments. Finding evidence for this community organization is important since compartmentalization may strongly affect food web robustness to perturbation. However, few studies have found unequivocal evidence of compartments, and none has quantified the suite of mechanisms generating such a structure. Here, we combine computational tools from the physics of complex networks with phylogenetic statistical methods to show that a large marine food web is organized in compartments, and that body size, phylogeny, and spatial structure are jointly associated with such a compartmentalized structure. Sharks account for the majority of predatory interactions within their compartments. Phylogenetically closely related shark species tend to occupy different compartments and have divergent trophic levels, suggesting that competition may play an important role structuring some of these compartments. Current overfishing of sharks has the potential to change the structural properties, which might eventually affect the stability of the food web.     

Hepatic monocyte chemoattractant protein-1 is upregulated by dietary cholesterol and contributes to liver steatosis

To assess the role of monocyte chemoattractant protein-1 (MCP-1/CCL2) in the development of fatty liver, we have used LDLr^−/− mice as an animal model of high-fat, high-cholesterol diet-induced liver steatosis. The rapid dietary induction of hepatic mRNA MCP-1 expression was paralleled by a concomitant increase in plasma MCP-1 that was strongly associated with the degree of liver steatosis. Hepatocytes showed an intense immunoreactivity for MCP-1 that was mainly located surrounding the hepatic lipid droplets. The intake of cholesterol also increased the concentration of MCP-1 in liver homogenates. This was accompanied by a differential expression of members of the PPAR family. Additionally, complete MCP-1 deficiency prevents the development of liver steatosis in LDLr^−/− mice and partial deficiency is accompanied by a certain protective effect. Our data also suggest that MCP-1 may be important in the regulation of hepatic insulin resistance and may represent a link between inflammation and metabolic diseases. We conclude that dietary cholesterol upregulation of hepatic MCP-1 may help to understand the role of circulating MCP-1 in conditions where liver derangements are clinically important and in the association of liver steatosis with the metabolic syndrome.     

A clinical registry of dementia based on the principle of epidemiological surveillance

Background  

Traditional epidemiological studies do not allow elucidating the reality of referral and diagnosis patterns of dementia in routine clinical practice within a defined territory. This information is useful and necessary in order to plan and allocate healthcare resources. This paper presents the results from a dementia case registry based on epidemiological surveillance fundamentals.     

Prevalence of dementia and major dementia subtypes in Spanish populations: A reanalysis of dementia prevalence surveys, 1990-2008

Background

To diagnose multiple sclerosis (MS), evidence for dissemination in space and time is required. There is no clear definition on how symptoms and signs of a patient indicate clinical dissemination in space. To provide a uniform approach on this subject, a clinical classification system was described recently differentiating patients with mono- and multifocal clinical presentation. Here we assess the predictive value of clinically defined dissemination in space at first presentation for time to clinically definite MS (CDMS).

Methods

Four hundred and sixty-eight patients with a first episode suggestive of MS were classified as clinically mono- or multifocal by two neurologists blinded to magnetic resonance imaging (MRI) results. These patients were part of the BENEFIT study in which 292 patients were randomized to interferon beta-1b (IFNB-1b) and 176 to placebo. By using Kaplan-Meier statistics the risk for CDMS was studied in mono- and multifocal patients of the placebo group, both with and without taking into account MRI measures of potential prognostic relevance.

Results

Time to CDMS was similar in monofocal and multifocal patients. In monofocal patients, the risk for CDMS over 2 years was significantly higher when ≥ 9 T2 lesions or at least one Gd-enhancing lesion were present at the first event or 3 or 6 months after the first event. In patients with multifocal presentation, these MRI measures had no significant added value in predicting time to CDMS.

Conclusion

These data indicate that a carefully performed neurological assessment of symptoms and signs, combined with lesions on MRI, is important for defining the risk of conversion to CDMS.

Trial Registration

The Benefit trial has been registered under NCT00185211 http://www.clinicaltrials.gov     

Seroprevalence and risk factors associated with Toxoplasma gondii in domestic pigs from Spain

Serum samples from 2970 (1400 sows, 1570 fattening) pigs, from 100 farms in the 10 main swine production regions in Spain were tested for antibodies against T. gondii by the modified agglutination test (MAT). Antibodies to T. gondii (MAT 1:25 or higher) were detected in 492 pigs (16.6%, 9.7% in fattening pigs and 24.2% in sows). The herd prevalence was 85.0% (95% CI: 78–92) and within-farm prevalence ranged from 2.9% to 92.8% (median = 17.6%). Statistically significant differences were observed among sampling regions with seroprevalence significantly higher in pigs from Valencia Community (27.3%), Extremadura (23.3%) and Catalonia (21.2%). A generalized estimating equations model indicated that the risk factors associated with T. gondii seroprevalence were: age, sows compared to fattening pigs (OR = 2.9; 95% CI = 1.83–4.53), lack of rodent control (OR = 1.9; 95% CI = 1.04–3.60) and presence of cats (OR = 1.6; 95% CI = 1.12–2.34). The seroprevalence observed in the present study indicates a widespread, although variable, exposure to T. gondii among domestic pigs in Spain, which might have important implications for public health. Management measures including control of rodents and cats on the farms could help to reduce the observed prevalence levels in Spain.