The ecological benefits of larger colony size may promote polygyny in ants.

How polygyny evolved in social insect societies is a long-standing question. This phenomenon, which is functionally similar to communal breeding in vertebrates, occurs when several queens come together in the same nest to lay eggs that are raised by workers. As a consequence, polygyny drastically reduces genetic relatedness among nestmates. It has been suggested that the short-term benefits procured by group living may outweigh the costs of sharing the same nesting site and thus contribute to organisms rearing unrelated individuals. However, tests of this hypothesis are still limited. To examine the evolutionary emergence of polygyny, we reviewed the literature to build a data set containing life-history traits for 149 Palearctic ant species and combined this data set with a reconstructed phylogeny. We show that monogyny is the ancestral state and that polygyny has evolved secondarily and independently throughout the phylogenetic tree. The occurrence of polygyny is significantly correlated with larger colony size, dependent colony founding and ecological dominance. Although polydomy (when a colony simultaneously uses several connected nests) tends to occur more frequently in polygynous species, this trend is not significant when phylogenetic history is accounted for. Overall, our results indicate that polygyny may have evolved in ants in spite of the reduction in nestmate relatedness because large colony size provides immediate ecological advantages, such as the more efficient use of temporal food resources. We suggest that the competitive context of ant communities may have provided the conditions necessary for the evolution of polygyny in some clades.

Troponin I as a Biomarker for Early Detection of Acute Myocardial Infarction.

Acute myocardial infarction (AMI) as the main cause of death among cardiovascular diseases is defined as a deficiency of oxygen that generates irreversible tissue necrosis in the heart muscle. For diagnostic measurements, the evaluation of cardiac markers concentration like cardiac triponin I (cTnI) in plasma or saliva thought the use of biosensors has become one of the most commonly applied strategies for prognosis of AMI. Inside this diagnostic devices, electrochemical (ECL) ones have been highly encourage to improve sensing capabilities by using different materials and configurations. In this review, the authors presents a summary of studies that involves cTnI detection using ECL biosensors modified with nanomaterials and related mechanisms.

AGING-ASSOCIATED COGNITIVE DECLINE IS REVERSED BY D-SERINE SUPPLEMENTATION.

Brain aging is a natural process that involves structural and functional changes that lead to cognitive decline, even in healthy subjects. This detriment has been associated with N-methyl-D-aspartate receptor (NMDAR) hypofunction due to a reduction in the brain levels of D-serine, the endogenous NMDAR co-agonist. However, it is not clear if D-serine supplementation could be used as an intervention to reduce or reverse age-related brain alterations. In the present work, we aimed to analyze the D-serine effect on aging-associated alterations in cellular and large-scale brain systems that could support cognitive flexibility in rats. We found that D-serine supplementation reverts the age-related decline in cognitive flexibility, frontal dendritic spine density, and partially restored large-scale functional connectivity without inducing nephrotoxicity; instead, D-serine restored the thickness of the renal epithelial cells that were affected by age. Our results suggest that D-serine could be used as a therapeutic target to reverse age-related brain alterations.SIGNIFICANT STATEMENTAge-related behavioral changes in cognitive performance occur as a physiological process of aging. Then, it is important to explore possible therapeutics to decrease, retard or reverse aging effects on the brain. NMDA receptor hypofunction contributes to the aging-associated cognitive decline. In the aged brain, there is a reduction in the brain levels of the NMDAR co-agonist, D-Serine. However, it is unclear if chronic D-serine supplementation could revert the age-detriment in brain functions. Our results show that D-serine supplementation reverts the age-associated decrease in cognitive flexibility, functional brain connectivity, and neuronal morphology. Our findings raise the possibility that restoring the brain levels of D-serine could be used as a therapeutic target to recover brain alterations associated with aging.

What are the consequences of ant-seed interactions on the abundance of two dry-fruited shrubs in a Mediterranean scrub?

Strong interactions between dry-fruited shrubs and seed-harvesting ants are expected in early successional scrubs, where both groups have a major presence. We have analysed the implications of the seed characteristics of two dry-fruited shrub species (Coronilla minima and Dorycnium pentaphyllum) on seed predation and dispersal mediated by harvester ants and the consequences of these processes on spatio-temporal patterns of plant abundance in a heterogeneous environment. We found that large C. minima seeds were collected much more (39%) than small D. pentaphyllum seeds (2%). However, not all of the removed seeds of these plant species were consumed, and 12.8% of the seeds were lost along the trails, which increased dispersal distances compared with abiotic dispersal alone. Seed dropping occurred among all microhabitats of the two plant species, but especially in open microhabitats, which are the most suitable ones for plant establishment. The two plant species increased their presence in the study area during the study period: C. minima in open microhabitats and D. pentaphyllum in high vegetation. The large size of C. minima seeds probably limited the primary seed dispersal of this species, but may have allowed strong interaction with ants. Thus, seed dispersal by ants resulted in C. minima seeds reaching more suitable microhabitats by means of increasing dispersal distance and redistribution among microhabitats. In contrast, the smaller size of D. pentaphyllum seeds arguably allows abiotic seed dispersal over longer distances and colonization of all types of microhabitats, although it probably also limits their interaction with ants and, consequently, their redistribution in suitable microhabitats. We suggest that dyszoochory could contribute to the success of plant species with different seed characteristics in scrub habitats where seeds are abundantly collected by seed-harvesting ants.

Predictive ultrasound factors of lymphatic invasion in rectal cancer: "extra-corporeal" study.

OBJECTIVE: the accuracy of preoperative endorectal ultrasound in the status evaluation of lymph nodes is around 50-70%, with a lack of eco-morphological patterns of clinical use. Since, accurate local staging is of great value in prognosis and decision-making we decided to analyze the referenced eco-morphological parameters in a try to find a proper predictive tool of clinical help that could improve the accuracy of rectal ultrasound. MATERIAL AND METHOD: the resected specimens of 24 patients that were operated on by radical surgery because rectal cancer, without preoperative radiotherapy were suspended in warm water and ultrasound scanned (360º circular probe with a transducer of 10 Mhz). All suspicious nodes were recorded and marked for the definitive histological report. RESULTS: from the 24 specimens, 318 nodes were imaged(210 benign and 100 involved). All ultrasound parameters analysed were significant but only lobulation, echogenicity and hilar reflection were independent values. An score system was design with the addition of all parameters that showed a sensitivity of 98%and specificity of 99,1%. CONCLUSIONS: our study shows that a careful study of ultra-sound lymph node images can get a high level of accuracy and better help in tailoring the treatment of any particular case.

Acute Myocardial Infarction Biosensor: A Review From Bottom Up.

Acute myocardial infarction (AMI) is a cardiovascular disease that is produced due to a deficiency of oxygen generating irreversible damage in the heart muscle. In diagnosis, electrocardiogram (ECG) investigation has been the main method but is insufficient, so approaches like the measurement of biomarkers levels in plasma or saliva have become one of the most commonly applied strategies for prognosis of AMI, as some of them are specifically related to a heart attack. Many tests are carrying on to determine biological markers changes, but usually, they present disadvantages related to time consumption and laborious work. To overcome the issues, researchers around the world have been developing different ways to enhance detection through the use of biosensors. These diagnostic devices have a biological sensing element associated to a physicochemical transducer that can be made from different materials and configurations giving place to different kinds of detection: Electrical/Electrochemical, Optical and Mechanical. In this review, the authors presents relevant investigations related to the most important biomarkers and biosensors used for their detection having in mind the nanotechnology participation in the process through the application of nanostructures as a good choice for device configuration.

Acorn crop size and pre-dispersal predation determine inter-specific differences in the recruitment of co-occurring oaks.

The contribution of pre-dispersal seed predation to inter-specific differences in recruitment remains elusive. In species with no resistance mechanisms, differences in pre-dispersal predation may arise from differences in seed abundance (plant satiation) or in the ability of seeds to survive insect infestation (seed satiation). This study aimed to analyse the impact of pre-dispersal acorn predation by weevils in two co-occurring Mediterranean oaks (Quercus ilex and Quercus humilis) and to compare its relevance with other processes involved in recruitment. We monitored the patterns of acorn production and acorn infestation by weevils and we conducted experimental tests of acorn germination after weevil infestation, post-dispersal predation and seedling establishment in mixed forests. Monitoring and experimental data were integrated in a simulation model to test for the effects of pre-dispersal predation in recruitment. In both oaks pre-dispersal acorn infestation decreased with increasing acorn crop size (plant satiation). This benefited Q. ilex which exhibited stronger masting behaviour than Q. humilis, with almost a single and outstanding reproductive event in 6 years. Acorn infestation was more than twice as high in Q. humilis (47.0%) as in Q. ilex (20.0%) irrespective of the number of seeds produced by each species. Although germination of infested acorns (seed satiation) was higher in Q. humilis (60%) than in Q. ilex (21%), this could barely mitigate the higher infestation rate in the former species, to reduce seed loss. Conversely to pre-dispersal predation, no inter-specific differences were observed either in post-dispersal predation or seedling establishment. Our results indicate that pre-dispersal predation may contribute to differences in seed supply, and ultimately in recruitment, between co-existing oaks. Moreover, they suggest that seed satiation can barely offset differences in seed infestation rates. This serves as a warning against overemphasising seed satiation as a mechanism to overcome seed predation by insects.

Ant community structure in citrus orchards in the mediterranean basin: impoverishment as a consequence of habitat homogeneity.

This study analyzes the structure and composition of ant communities in citrus orchards in Catalonia (northeast Spain) and compares them with the ant fauna found in natural communities of the region. In the citrus orchards considered in this study, the most abundant species were Lasius niger and Pheidole pallidula, which are behaviorally dominant species. Two other dominant species, Linepithema humile and Tetramorium caespitum, were also abundant, although only in one orchard. Species richness and diversity in the studied orchards were low compared with natural communities: although in orchards, there were few species and low diversity values, in natural communities, the number of species was higher and diversity also increased. This reduction of species richness and diversity was not modified by edge effects: only light and local differences were found between the inner part of the orchards and the orchard margins, and differences among orchards were greater than differences between inner parts and edges. The activity peaks of the different ant species actively foraging on these citrus orchards were distributed throughout the whole activity period of ants. Overall, the composition of ant communities present in the citrus orchards of this study was extremely poor. This agrees with the fact that monocultures are ecosystems associated with an inevitable loss of biodiversity and abundance of insect populations.

Age-specific, density-dependent and environment-based mortality of a short-lived perennial herb.

Density-independent and density-dependent processes affect plant mortality. Although less well understood, age-specific mortality can also play an important role in plant mortality. The goal of this study was to analyse several factors accounting for mortality in the Mediterranean short-lived perennial herb Lobularia maritima. We followed three cohorts of plants (from emergence to death) during 4 years in field conditions. We collected data on plant mortality of the effect of biotic agents (moth larvae and mycoplasma-like organisms, MLOs) and environmental variables. We also estimated density-dependent relationships affecting the fate of seedlings and adults. Results show that cohorts differed in their survival curves and ageing significantly increased mortality risk. Seedling mortality was density-dependent whereas adult mortality was not affected by density. MLO infection led to higher plant mortality whereas moth larvae attack did not affect plant mortality. In general, seedlings and adult plants experienced the highest mortality events in summer. We found, however, weak relationships between weather records and plant mortality. Age and size structures were not correlated. Overall, this study provides a comprehensive review of age-specific, density-dependent and density-independent factors that account for mortality of L. maritima plants throughout their life cycle in field conditions, highlighting the fact that age is an important factor in determining plant population dynamics.

Exploitative strategies of the invasive Argentine ant (Linepithema humile) and native ant species in a southern Spanish pine forest.

The Argentine ant, Linepithema humile (Mayr, 1868), is displacing native ant species in Doñana National Park (Spain). This paper discusses the results of experiments aimed at analyzing exploitation competition between the invading species and other ant species in a park community. The Argentine ant was found to implement several strategies favoring its success in exploitation competition: mass recruitment, use of various microhabitats (on the ground and in trees), and activity over a wide range of temperatures. Although these strategies were not exclusive to L. humile, their joint use, together with the large number of workers forming each "unicolony," conferred a clear advantage for resource exploitation. Some native species were more severely affected than others by the presence of L. humile in terms of both abundance and behavior. The worst affected species were those whose ecological characteristics were similar to those of the Argentine ant, e.g., Pheidole pallidula (Nylander, 1849); the species least affected was Cataglyphis floricola Tinaut, 1993, possibly because of its subordinate and thermophilous nature (little overlap of daily activity rhythms with the exotic species).

Spin-orbital effects in metal-dichalcogenide semiconducting monolayers.

Metal-dioxide &metal-dichalcogenide monolayers are studied by means of Density Functional Theory. For an accurate reproduction of the electronic structure of transition metal systems, the spin orbit interaction is considered by using fully relativistic pseudopotentials (FRUP). The electronic and spin properties of MX2 (M = Sc, Cr, Mn, Ni, Mo &W and X = O, S, Se &Te) were obtained with FRUP, compared with the scalar relativistic pseudopotentials (SRUP) and with the available experimental results. Among the differences between FRUP and SRUP calculations are giant splittings of the valence band, substantial band gap reductions and semiconductor to metal or non-magnetic to magnetic "transitions". MoO2, MoS2, MoSe2, MoTe2, WO2, WS2 and WSe2 are proposed as candidates for spintronics, while CrTe2, with µ ~ 1.59 µB, is a magnetic metal to be experimentally explored.

Health information technologies for sexual and reproductive health: Mapping the evidence in Latin America and the Caribbean.

In Latin America and the Caribbean (LAC), the sexual and reproductive health (SRH) of populations is a high priority for governments. Health information technologies (HITs) have been proposed as tools to close access gaps for SRH services. We developed an "evidence map" through a systematic search of articles published between 2005 and 2015 about the use of HITs to enhance SRH services in LAC countries. Two hundred and thirty-two registries were identified and screened. Thirty-one were eligible for full-text assessment. Most of the documents retrieved correspond to information provided by technology developers, targeting primarily the prevention of sexually transmitted infections and adolescent health. Although there has been clear progress in the use of HITs for SRH in the region, many institutional and technological challenges persist. Further studies should be carried out to test the beneficial effects of HITs on improving access to SRH services.

Patterns of diversity and composition of Mediterranean ground ant communities tracking spatial and temporal variability in the thermal environment.

The present study analyzed ant community structure and the factors affecting it in the Spanish Mediterranean area. The aim of this study was to test whether temperature controls the composition and diversity of the ground ant fauna and the spatial and temporal distribution of dominance groups along adjacent communities. The main descriptors of community structure (except perharps species richness) were found to vary along the gradient of vegetation cover: increased vegetation cover resulted in an increase in the relative abundance of the most common species, which led to a significant decrease in species evenness, together with a reduction in total ant density on the ground. In open habitats, dominant and subordinate species were abundant during different periods of the day, and this led to an increase in species evenness. In areas with high vegetation cover, dominants benefited from the lower temperatures by lengthening their periods of activity. This resulted in a decrease in the abundance of subordinate species, and in lower evenness. Seasonal patterns in community structure tracked temperature fluctuations and varied between habitat types. Evenness was similar in the two habitat types in spring, but increased in grasslands and decreased in shrublands/forests in summer. Species richness did not vary between seasons or habitat types. The relative abundance of dominance groups in the two types of habitats showed a different pattern between seasons. In grasslands, subordinates increased and dominants decreased their relative abundance from spring to summer, while in shrublands/forests, the opposite pattern was found. The overall conclusion from this study is that ground ant communities in open areas are primarily regulated by temperature variations, while in shrublands and forests, dominant species are more abundant, and competitive interactions appear to be the major structuring force.

Prevalence of coronary artery disease risk factors in workers at the general hospital of Mexico of the ministry of health.

OBJECTIVE: To assess the prevalence of coronary risk factors in 2,463 health-care workers at the General Hospital of Mexico. METHODS: The study participants--1,620 women (65.8%) and 843 men (34.2%)--ranged in age from 16 to 65 years old. Study subjects were classified into five occupational subgroups: maintenance workers, 477 (19.4%); administrators, 697 (28.3%); physicians, 495 (20.1%); nursing staff, 559 (22.7%); and students, 235 (9.5%). For each participant, a clinical history was elicited, anthropometric determinations were done, and samples were obtained for determining blood glucose, total cholesterol, low-density lipoprotein, high-density lipoprotein, and triglyceride levels. RESULTS: Cholesterol levels above 6.2 mmol/L (>240 mg/dL) were found in 14.9% of the women and 14.8% of the men in the overall study group. Triglyceride levels of more than 2.25 mmol/L (>200 mg/dL) were found in 471 participants (19.1%). The prevalence of obesity was 13.5%, and high blood pressure was detected in 22.2% of study participants. Only 32.2% of subjects engaged in physical exercise one or more times per week; moreover, 32% of those surveyed smoked. The prevalence for diabetes mellitus was 6.25%. The multifactorial coronary risk index was high in 13.2% of men and 43.2% of women older than 30 years of age. CONCLUSION: This study confirmed the high prevalence of risk factors for cardiovascular diseases in personnel of the General Hospital of Mexico. Because many of these risk factors are modifiable, educational efforts and preventive measures should be implemented.

Effects of long-term treatment with lansoprazole and omeprazole on serum gastrin and the fundic mucosa.

OBJECTIVE: To compare the effects of long-term lansoprazole and omeprazole treatment (6 months) on serum gastrin levels. PATIENTS: Forty duodenal ulcer patients without previous treatment with proton pump inhibitors were randomized to receive either 20 mg/day or omeprazole or 30 mg/day of lansoprazole. Serum gastrin levels were determined on entry and every 2 months. On finalizing the study antral and fundic biopsies were obtained for immunohistochemical analysis of the enterochromaffin-like cell population. RESULTS: Before starting the treatment fasting serum gastrin was similar in both groups (108.7 +/- 60.9 pg/mL omeprazole; 102.7 +/- 56.9 pg/mL lansoprazole). The treatment with either omeprazole or lansoprazole increased serum gastrin levels, but the increase was mild, maximal at 2 months and similar between omeprazole and lansoprazole (113.44 +/- 114.9 pg/mL omeprazole vs 166.1 +/- 117.9 pg/mL lansoprazole; p > 0.05). When serum gastrin levels were individually analyzed by patient, most were below 200 pg/mL and only 3 patients (1 omeprazole/2 lansoprazole) had levels near 500 pg/mL which were not correlated with enterochromaffin-like cell hyperplasia. CONCLUSIONS: Long-term treatment with either omeprazole or lansoprazole is safe, at least during 6 months, and results in mild hypergastrinemia. No differences between these two drugs were observed.

[Effect of exogenous administration of platelet-derived growth factor and epidermal growth factor on duodenal ulcer healing in rats treated with indomethacin]. / Efecto de la administración exógena de PDGF y EGF en la cicatrización de la úlcera duodenal en ratas tratadas con indometacina.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) delay peptic ulcer healing through mechanisms that are still not entirely understood. Growth factors play a significant role in healing. AIM: To evaluate whether exogenous administration of platelet-derived growth factor (PDGF) reverses the effect of indomethacin in experimental duodenal ulcers in rats and to define the potential mechanisms involved in this process. METHOD: Duodenal ulcer was induced in male Wistar rats with acetic acid. The rats were then administered indomethacin (2 mg/kg/day), PDGF-BB (30 ng/100 g/day), epidermal growth factor (EGF) (50 /kg/day) or famotidine (positive control) or the possible combinations of these. Macroscopic area, reduction in microscopic diameter, epithelial and granulation tissue proliferation, collagen secretion by granulation tissue, and gastric acid secretion were analyzed. RESULTS: Indomethacin delayed duodenal ulcer healing by decreasing cellular proliferation and inhibiting collagen secretion. PDGF and EGF accelerated healing and reversed the effects of indomethacin. The mechanisms involved were associated with an increase in collagen proliferation and secretion without affecting gastric acid secretion. Famotidine also accelerated healing and reversed the effect of indomethacin, and these effects were associated with a marked inhibition of gastric acid secretion and increase in collagen secretion by granulation tissue. CONCLUSIONS: Exogenous administration of PDGF and EGF accelerated healing and reversed the harmful effects of indomethacin in an experimental model of duodenal ulcer.

Ant-mediated expansion of an obligate seeder species during the first years after fire.

Most obligate seeder species build up a soil seed bank that is associated with massive seed germination in the year immediately after a fire. These species are also shade-intolerant and disappear when vegetation cover closes, creating unsuitable conditions for seedling recruitment. The only way for these plants to expand their populations is when habitats suitable for seedling recruitment arise (i.e. in years immediately after a fire). However, short primary seed dispersal of obligate seeders does not allow these plants to colonise the suitable habitats, and these habitats can only be colonised by secondary seed dispersion. We hypothesised that Fumana ericoides, an obligate-seeding small shrub, not only establishes abundantly in the first year after fire, but also expands its local range in the following years due to secondary dispersal by ants while suitable habitats are still available. We tested this hypothesis using experimental studies and a simulation model of potential population expansion in a recently burned area. Results showed that F. ericoides not only established prolifically in the year immediately after fire, but was also able to recruit new individuals and expand its population in the years following the fire, despite a low germination rate and short primary seed dispersal. Ant-mediated seed dispersal and availability of suitable habitats were key factors in this phenomenon: ants redistributed seeds in suitable habitats while they were available, which accelerated the expansion of F. ericoides because new plants established far away from the core population.

[Late postgastrectomy sequellae: primary cancers of the gastric stump]. / Secuelas tardías posgastrectomías: los cánceres primitivos del muñon gástrico.

The authors describe 8 cases of carcinoma of the gastric stump, 6 after Billroth II and 2 after Billroth I resection. They were observed after a free interval of 18.5 years and formed 3 per 100 of the treated gastric and duodenal malignant tumors. The authors indicate the surgical technique they recommend to prevent the malignant degeneration following operations for benign gastric or duodenal ulcers.

[The efficacy, safety and tolerance of fluvastatin sodium 40 mg in patients with hyperlipidemia type IIA]. / Eficacia, seguridad y tolerabilidad de la fluvastatina sódica 40 mg en pacientes con hiperlipidemia tipo IIA.

Fluvastatin sodium is the first wholly synthetic 3 hydroxy-3-methylglytary 1 coenzyme A reductase inhibitor. It reduces cholesterol synthesis, enhances low density lipoprotein catalysis and hepatocyte LDL receptor expression. To evaluate the efficacy, tolerability and safety of fluvastatin sodium 40 mg once a day, we studied 40 patients with type IIA dyslipidemia. We observed a statistically significant reduction in total cholesterol (20.7%, p < 0.01), low density lipoprotein cholesterol (29.5%, p < 0.01), triglycerides (10.56%, p N.S.), very low density lipoprotein cholesterol (10.56%, p N.S.), C-LDL:C-HDL (33.7%, p < 0.01) and an increase in high density lipoprotein cholesterol (2.8%) after 12 weeks of treatment. No patient reported side effects and no clinically significant modifications in safety parameters were observed during the study. We conclude that fluvastatin sodium 40 mg once daily is efficacious, safe and well tolerated in the treatment of type IIA primary dyslipidemia.

Multiple cavernous hemangioma of the kidney.

A case of renal angiomas, located on the tip of the papillae, presented with severe hematuria which required several blood transfusions. Radiological studies including arteriography were negative. The diagnosis was confirmed by intraoperative nephroscopy and histology.