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In oviparous species, pesticides may affect embryo survival via maternal transfer or contaminant absorption from the soil, thus representing an important cause of population decline. Maternal transfer is a source of contamination during vitellogenesis and oviductal egg retention. Currently, there is still limited evidence of the potential risk of embryonic exposure routes in reptiles. We investigated whether different agricultural treatments affect embryo, egg, and hatchling development and survival in the Italian wall lizard. We kept gravid females from conventional and control fields in captivity until oviposition and, after eggs being incubated in a pesticide-free environment, offspring morphology and performance (running speed) were assessed. Our results showed that the size of the mother positively influences the number of the eggs and offspring, as well as hatching body condition. Bigger females from conventional treatments tended to lay more eggs. Moreover, at equal female body conditions, eggs and hatchlings from conventional treatments had worse quality (i.e., smaller size and lower body condition) than those from control areas. No effect of treatment was observed on hatchling locomotor performance. In conclusion, our study provided new insights of the direct and indirect effects of field management (i.e., pesticide exposure) on females' reproductive success through the alteration of female's behaviour, which in turn may affect offspring development and health. [ABSTRACT FROM AUTHOR]

For many years lizard thermal ecology studies have relied on the use of contact thermometry to obtain internal body temperature (T b ) of the animals. However, with progressing technology, an interest grew in using new, less invasive methods, such as InfraRed (IR) pyrometry and thermography, to infer T b of reptiles. Nonetheless few studies have tested the reliability of these new tools. The present study tested the use of IR cameras as a non-invasive tool to infer T b of lizards, using three differently body-sized lacertid species ( Podarcis virescens, Lacerta schreiberi and Timon lepidus ). Given the occurrence of regional heterothermy, we pairwise compared thermography readings of six body parts (snout, eye, head, dorsal, hind limb, tail base) to cloacal temperature (measured by a thermometer-associated thermocouple probe) commonly employed to measure T b in field and lab studies. The results showed moderate to strong correlations (R 2 =0.84–0.99) between all body parts and cloacal temperature. However, despite the readings on the tail base showed the strongest correlation in all three species, it was the eye where the absolute values and pattern of temperature change most consistently followed the cloacal measurements. Hence, we concluded that the eye would be the body location whose IR camera readings more closely approximate that of the animal's internal environment. Alternatively, other body parts can be used, provided that a careful calibration is carried out. We provide guidelines for future research using thermography to infer Tb of lizards. [ABSTRACT FROM AUTHOR]

Ecological niche models (ENMs) will successfully identify a species' ecological niche, provided that important assumptions are fulfilled, namely environment equilibrium and niche equality across the distribution. Violations may seriously affect ENM reliability, leading to erroneous biogeographic conclusions and inappropriate conservation prioritisation. We evaluate the robustness of ENMs against incomplete knowledge of distribution with a real example, the threatened Iberian lizard Podarcis carbonelli , whose distribution was gradually discovered over a long time period. We used several ENM methods for presence-only data (Maxent, ENFA, Bioclim, and Domain) to infer the realised ecological niche at two spatial resolutions (1 km and 200 m). The distribution data were split into four partial datasets corresponding to separate subranges: Central System (CS); Viseu-Aveiro (VA); Atlantic coast (AC); and Doñana (DO). We then accumulated the datasets following the species discovery sequence: CS + VA, CS + VA + AC, and CS + VA + AC + DO. Niche equivalence and similarity between partial models were compared using Ecospat. ENMs were strongly affected by the violation of niche equilibrium; only the VA subrange forecasts the complete species range. ENMs were also sensitive to the violation of niche equality: only VA models were similar to the Iberian model, altitude being the most important variable followed by annual precipitation, maximum temperature in July, and annual radiation. When the ENMs were applied only to the first subrange discovered (CS), only the VA area was predicted, while the other subranges might have remained unknown, thus compromising conservation strategies. As assumptions of niche equilibrium and equality were violated, likely owing to the species' ecological multimodality, the models generated were biased and of limited predictive value. ENMs are useful tools in biogeography and conservation, but only if their basal assumptions are achieved. Partial models may be useful if they are considered as representing different suitable habitats. [ABSTRACT FROM AUTHOR]

Understanding if morphological differences between organisms that occupy different environments are associated to differences in functional performance can suggest a functional link between environmental and morphological variation. In this study we examined three components of the ecomorphological paradigm – morphology, locomotor performance and habitat use – using two syntopic wall lizards endemic to the Iberian Peninsula as a case study to establish whether morphological variation is associated with habitat use and determine the potential relevance of locomotor performance for such an association. Differences in habitat use between both lizards matched patterns of morphological variation. Indeed, individuals of Podarcis guadarramae lusitanicus , which are more flattened, used more rocky environments, whereas Podarcis bocagei , which have higher heads, used more vegetation than rocks. These patterns translated into a significant association between morphology and habitat use. Nevertheless, the two species were only differentiated in some of the functional traits quantified, and locomotor performance did not exhibit an association with morphological traits. Our results suggest that the link between morphology and habitat use is mediated by refuge use, rather than locomotor performance, in this system, and advise caution when extrapolating morphology-performance-environment associations across organisms. [ABSTRACT FROM AUTHOR]

Prey response to different predators is complex and can include diverse antipredatory strategies. In syntopic populations of competing species common predators can play a mediator role thus influence the interaction out-come of prey-species in an indirect way. We studied differences in antipredator response in two competing lizards in syntopy in a multi-predator environment. Studied prey species, Iberolacerta horvathi and Podarcis muralis , are likely to compete in syntopic populations limited in size and have similar morphology and ecology but exhibit fine-scale ecophysiological differences. Taking into account interspecific differences in ecophysiology we expected that I. horvathi as a more precise thermoregulator would be less prone to use refuges that represent a thermal cost (are colder than outside). The pattern we found was the opposite of our expectations; I. horvathi escaped at greater distances and remained in the refuge for longer before re-emerging than P. muralis . Second part of the study revealed that both species were able to recognize chemical cues of predator snakes (represented as higher tongue flick rates in the presence of scents of predator snakes in comparison to control). Behavioral responses, which are linked with stressful situations connected to saurophagous snakes, were more frequent and variable in I. horvathi . Overall, antipredator responses seem to be more pronounced in I. horvathi than in P. muralis. While this “more cautious” attitude of I. horvathi should provide higher short-term benefits (higher survival rates), this would hold true only in populations where predation pressure is high. Otherwise it carries substantial time and thermoregulatory costs. For I. horvathi , costs of refuge use should be even higher due to narrower dimensions of their ecophysiological fundamental niche. Such divergences in antipredator behavior are expected to shape the relationships between both species in syntopic populations modulated by common predation pressure and habitat structure. [ABSTRACT FROM AUTHOR]

Abstract: While glaciations constituted the major recent paleoclimatic event, inducing multiple oscillations on species’ ranges, future and rapid shifts are expected if global warming predictions are confirmed. Investigating the whole temporal spectrum of range shifts is of conservation importance since species suffering contractions during the interglacial periods may continue contracting in a warming scenario; lizards provide excellent models for such analysis. We investigated the historical biogeography of Podarcis carbonelli, a lacertid lizard endemic to the Western Iberian Peninsula with a fragmented distribution, likely resulting from an important reduction during the Pleistocene and Holocene. We modelled with Maxent its current distribution and projected it to past (Last Interglacial—LIG and Last Glacial Maximum—LGM) and future (2020, 2050 and 2080) scenarios. The consensus models predicted a larger suitable area than the currently occupied, in areas with a high humidity and low maximum temperatures. The LIG model indicated a reduced range restricted to the northern Portuguese coast, and the LGM model, a suitable area larger than the current. After the LGM, areas with suitable climate started regression till present, which is predicted to continue in future, with a northward range shift and a loss of suitable climate from inland zones towards the coast. The range of P. carbonelli may have been oscillating from the northern Portuguese coast to the south and to inland during the Pleistocene. The Portuguese West Atlantic coast, harbouring a substantial part of the species’ genetic diversity, with suitable climate during the LIG and LGM and forecasted to remain in the future, is not currently protected but deserves conservation priority. [Copyright &y& Elsevier]

Abstract: A variety of different methods are available for investigating the effects of past climate fluctuation on biota. Among them, molecular phylogeography and species distribution modeling approaches have been shown to be especially useful tools to trace past climate induced modifications of species’ geographic distributions. The results of both analytical approaches are here combined to better understand the influences of past climate changes on the fragmented distribution pattern of the lizard genus Iranolacerta that currently occurs in the northwest and central Zagros Mountains of Iran. While Iranolacerta zagrosica is restricted to few localities and cannot be modeled, the potential distribution of Iranolacerta brandtii suggested a large region of unfavorable habitat between northwest and the central Zagros Mountains populations. From the phylogenetic perspective, both species display deep genetic separation likely predating the Pleistocene. However, limited genetic diversity across this divided range of I. brandtii implies that the current separation is recent. Deeper genetic divergences were, nevertheless, uncovered within the northwest population. Since no recent geological events explain these results, the most likely explanation for such a distribution pattern is due to past climate fluctuations. Both sources of evidence suggest that during the early Holocene the northwest and Zagros populations of I. brandtii were connected, and the current pattern was shaped with their disconnection in the early Holocene. Further studies may identify potential glacial refugia for other species in this biodiverse region. [Copyright &y& Elsevier]

Abstract: At the European level, lacertid lizards have been proposed as potential model species for reptile ecotoxicology. We studied demographic and morphological aspects of natural field subpopulations of Podarcis bocagei inhabiting similar agricultural habitats which were either regularly exposed to pesticides, or not. Parameters examined in this study included population size and density, sex ratio, adult body size, fluctuating asymmetry in femoral pores and parasite prevalence. In general, we detected few statistically significant differences between the exposed and reference subpopulations. Although field situations are ecologically complex and factors other than pesticides may be acting, the absence of observable effects on field subpopulations is probably indicative that lizards are coping or compensating for this level of exposure. [Copyright &y& Elsevier]

Abstract: By reaction of 2,6-diformyl-4-methylphenol (BDF) with the amino acids l-His and l-Ala in the presence of VOCl2, two new oxovanadium(IV) complexes with the ligand obtained by the 1:2 condensation of BDF with the amino acids, BDF–His and BDF–Ala, were synthesised. The compounds were characterised in the solid state by elemental analyses, IR, CD and magnetic susceptibility measurements, and in the mother liquor by EPR. In water-containing solutions, BDF–Ala and BDF–His partially hydrolyse but the degree of Schiff base formation increases upon addition of VOSO4. The equilibria in the system VIVO2++BDF–His were studied by spectroscopic methods (EPR, CD and UV–Vis) in the pH range 1.5–12. The coordination behaviour of the ligand changes as the pH increases, leading to the formation of four main species all involving Ophen as donor atom. Plausible binding modes are discussed based on the spectroscopic results. [Copyright &y& Elsevier]

Urban biodiversity plays a crucial role in the functioning of urban ecosystems and significantly impacts the well-being and quality of life for city residents. By focusing on the city of Porto as a case study, the influence of local-scale land cover evolution on urban biodiversity is investigated, using species richness of birds, reptiles, and amphibians as indicators, within a multimodel inference framework. The results underscore the importance of past land cover and land cover legacy in shaping urban biodiversity. Birds, reptiles, and amphibians respond positively to older vegetation patches but negatively to long-established urban areas. Birds exhibit adaptability by positively responding to recent vegetation, while amphibians tend to avoid newly vegetated zones. The fragmented distribution of amphibians and reptiles in Porto suggests limited mobility and a potential delayed response to habitat loss and isolation. Reptiles benefit from both wooded and herbaceous habitats, emphasizing the importance of local spatial diversity, while water elements are critical for amphibians, although many aquatic habitats in the urban context may not be suitable. Modeling results guide the identification of priority areas for urban biodiversity conservation in Porto, informing decision-makers, urban planners, and conservationists. This spatially explicit research aids efforts to create more ecologically resilient and biodiverse urban environments. It highlights the role of historical land cover and the unique responses of different vertebrate groups to urbanization, contributing to our understanding of urban biodiversity dynamics and sustainable urban development. • Vertebrate groups respond positively to vegetation, negatively to artificial cover. • Birds adapt to both older and recent vegetation, due to higher mobility. • Herpetofauna relies on small-scale habitat diversity, such as water features. • Herpetofauna's fragmented distribution suggests delayed response to habitat loss. • Spatial prioritization is particularly relevant for urban planning and management. [ABSTRACT FROM AUTHOR]

Most animals face predators in their daily life and have evolved antipredator strategies that promote survival while minimizing escaping costs. For example, many animals often hide into refuges when chased. Ectotherms rely on external sources of heat to raise their body temperature, and thermoregulate to keep their body temperature close to the optimal for performance. For many ectotherms living in temperate areas, it can be expected that they pay a cost in terms of heat loss while staying hidden. Indeed, refuges are often more thermally unsuitable than the external environment. Hence, the aim of this study was to assess if and to what extent hiding may result in a decrease of body temperature in a temperate lizard. We used infrared technology to measure the body temperature of a large-sized lizard (Timon lepidus) before individuals escaped from a simulated predation attempt to hide inside a refuge, and after they emerged back from the refuge. We quantified the change of body temperature that lizards experienced while hiding. Results show that while the decrease in body temperature covaried with the time spent hidden, it was also affected by the initial body temperature. Our key finding is that the time spent hidden depends mostly on the temperature inside the refuge. Indeed, lizards hiding in warmer refuges spent more time hidden, likely benefitting from a reduced cooling rate. This suggests that lizards perceive and evaluate the thermal quality of their refuges and integrate this information to react to predation attempts and minimize the potential thermal consequences of hiding. • Potential thermal consequences of hiding are largely unknown in ectotherm species. • We measured lizard body temperature before and after hiding from a predator. • Temperature decrease covaried with hiding time and was modulated by initial body temperature. • Hiding time was positively correlated with the thermal quality of refuges. • We quantified for the first time how hiding reduces body temperature of a lizard. [ABSTRACT FROM AUTHOR]

• Geckos were tested in the lab to choose refuge size, temperature, and presence of conspecifics. • They first chose larger refuges regardless their temperature and then smaller cold refuges. • Aggregation behaviour was influenced by adulthood and sex. • Size-related disparities between individuals modulates aggregation patterns. • Findings are relevant for social behaviour in ectotherms and useful for management. In small sedentary ectotherms, patterns of spatial use result from the interplay between multiple, often conflicting factors, including abiotic and biotic interactions. Evaluating the costs and benefits of these pressures is crucial to make correct behavioural decisions in terms of fitness. The insular São Vicente's wall gecko Tarentola substituta provides a relatively simple model system to study these questions as it inhabits arid rocky habitats where refuges are limited, density of conspecifics is high, and terrestrial predators are almost absent. In the field, adults tend to find diurnal shelter under mid-sized rocks, frequently in male-female couples, while juveniles occupy small rocks which are thermally suboptimal. A lab experiment was conducted to determine the roles of ecological (shelter size and temperature) and social (conspecifics) factors in refuge selection. Single and pair combinations of geckos of different age and sex classes were allowed to select among four refuges: cold small, hot small, cold large, or hot large rock. Based on previous studies, we hypothesized that larger and thermally buffered rocks would be the preferred refuges, and that adult male-female pairs under the same rock would be more frequent than other combinations.Geckos primarily selected larger shelters, trading off the presence of conspecifics against thermal quality. In social terms, sex, adult condition and size-related disparity shaped the patterns of aggregation, resulting in lower aggregation frequencies between adults and juveniles and even between juveniles of different sizes. These results reasonably match field observations suggesting selection of rocks as diurnal retreats according to their thermal properties, and social aggregations mainly involving adult males and females but not juveniles. Overall, this combined evidence provides insights on the spatial ecology of geckos, and likely other ectotherms, under conditions of low predation, limited resources and high intraspecific competition, such as those prevailing on island systems. [ABSTRACT FROM AUTHOR]

Sister species living in sympatry offer the opportunity to study the degree of divergence in their ecological, physiological and life-history traits. It has been hypothesized that closely related species with overlapping distribution should differ in their niche to reduce competition for resources. Furthermore, the investigation of sympatric species may shed light on how they may coexist without outcompeting each other. In the present study, we assess the degree of physiological divergence in two sympatric lacertid lizards, Podarcis bocagei and Podarcis guadarramae lusitanicus . These species share a Pliocenic ancestry and overlap at a both geographical and ecological scale. We assessed their thermal preferences and water loss rates, two physiological traits considered stable across congeneric species. We found that the two species differ in both traits, with P. bocagei selecting higher temperature than P. g. lusitanicus and losing more water than the latter at and above its preferred temperature. The results also showed that for both species body size has a relevant impact on thermal and hydric traits, with bigger individuals losing proportionally less water and selecting higher temperatures. These results, combined with previous evidence, suggest that physiological mechanisms, ecological preferences and morphology probably allow these two species to overlap in their distribution while selecting different microhabitats and thus decreasing possible competition between them. [ABSTRACT FROM AUTHOR]

Aerobic respiration is the main energy source for most eukaryotes, and efficient mitochondrial energy transfer greatly influences organismal fitness. To survive environmental changes, cells have evolved to adjust their biochemistry. Thus, measuring energy metabolism at the subcellular level can enhance our understanding of individual performance, population dynamics, and species distribution ranges. We investigated three important metabolic traits at the subcellular level in five lacertid lizard species sampled from different elevations, from sea level up to 2000 m. We examined hemoglobin concentration, two markers of oxidative stress (catalase activity and carbonyl concentration) and maximum rate of metabolic respiration at the subcellular level (potential metabolic activity at the electron transport system). The traits were analysed in laboratory acclimated adult male lizards to investigate the adaptive metabolic responses to the variable environmental conditions at the local sampling sites. Potential metabolic activity at the cellular level was measured at four temperatures – 28 °C, 30 °C, 32 °C and 34 °C – covering the range of preferred body temperatures of the species studied. Hemoglobin content, carbonyl concentration and potential metabolic activity did not differ significantly among species. Interspecific differences were found in the catalase activity, Potential metabolic activity increased with temperature in parallel in all five species. The highest response of the metabolic rate with temperature (Q 10) and Arrhenius activation energy (E a) was recorded in the high-mountain species Iberolacerta monticola. [Display omitted] • Metabolic traits - oxygen delivery, electron transport, and antioxidant activity - were studied in five lacertid species. • Only catalase activity differed significantly among the species. • Temperature has a positive effect on potential metabolic activity in all species. • The mountain species shows the lowest and marginally significant metabolic rate response to temperature changes. [ABSTRACT FROM AUTHOR]

Sympatric species from the same ecological guild, that exhibit partial altitudinal segregation, can potentially interact in areas of syntopic occurrence. Besides general species' ecology, physiology can provide important answers about species interactions reflected in altitudinal patterns. Lizards Podarcis muralis and Iberolacerta horvathi exhibit partial altitudinal segregation, while they strongly resemble in overall morphology and ecology (diet, daily and seasonal activity pattern), but show certain degree of physiological dissimilarity. They have similar mean preferred body temperatures and patterns of seasonal and daily variations but differ in the magnitude of seasonal variation. Since an ectotherm metabolism is highly dependent on body temperature, thermoregulation is expected to directly affect their metabolism. We compared metabolic rates of adult males from an area of sympatry, measured under two temperature regimes (20 °C and 28 °C). Both species increased metabolic rates with temperature in a similar pattern. We also compared electron transport activity from tail tissues which provide values of species' potential metabolic activity (enzymatic capacity). Species clearly differed in potential metabolic activity; I. horvathi attained higher values than P. muralis . No difference was detected in how species exploited this potential (calculated from the ratio of electron transport activity and metabolic rates) . However, we observed higher potential metabolic activity I. horvathi which together with the ability to thermoregulate more precisely could represent a higher competitive advantage over P. muralis in thermally more restrictive environments such as higher altitudes. Understanding of metabolism seems to provide valuable information for understanding recent distributional patterns as well as species interactions. [ABSTRACT FROM AUTHOR]

Abstract: Amphibians epitomize the modern biodiversity crisis, and attract great attention from the scientific community since a complex puzzle of factors has influence on their disappearance. However, these factors are multiple and spatially variable, and declining in each locality is due to a particular combination of causes. This study shows a suitable statistical procedure to determine threats to amphibian species in medium size administrative areas. For our study case, ten biological and ecological variables feasible to affect the survival of 15 amphibian species were categorized and reduced through Principal Component Analysis. The principal components extracted were related to ecological plasticity, reproductive potential, and specificity of breeding habitats. Finally, the factor scores of species were joined in a presence-absence matrix that gives us information to identify where and why conservation management are requires. In summary, this methodology provides the necessary information to maximize benefits of conservation measures in small areas by identifying which ecological factors need management efforts and where should we focus them on. [Copyright &y& Elsevier]

Abstract: As part of a wider study examining the impacts of corn pesticides on lacertid lizards in north-western Portugal, we examined various physiological, biochemical, and histological biomarkers of exposure and effect among field populations of Podarcis bocagei. Biomarkers included body condition index, standard metabolic rate, locomotor performance, parasitization, glutathione oxidative pathways and related enzyme activity, lipid peroxidation and liver and testis histology. Few of the various biomarkers investigated provided statistically significant evidence of toxic effect. However, using a weight of evidence approach, we conclude that pesticides are affecting lizards living in the vicinity of pesticide exposed corn agriculture sites. Lizards from these locations present a profile of animals under metabolic stress with reduced condition indices, increased standard metabolic rate, lower incidence of hepatocyte vacuolation, altered iron metabolism, increased activation of GSH oxidation pathways, and even increased prevalence of hemoparasites. [Copyright &y& Elsevier]

Abstract: The XRD structure and the influence of the conformation in the molecular orbitals of the pteridine-benzoylhydrazone ligand (BZLMH=benzoylhydrazone of 6-acetyl-1,3,7-trimethyllumazine, lumazine=(1H,3H)-pteridin-2,4-dione) have been studied. Complexes of BZLMH with nickel(II), zinc(II) and mercury(II) have been prepared and spectroscopically characterized by IR, NMR and fluorescence spectroscopy; also XRD studies have allowed to establish two different coordinative patterns in the complexes [Ni3(BZLMH)3(OH)(H2O)(CH3CN)2](ClO4)5 ·2H2O·CH3CN (2) and [Zn(NO3)(BZLMH)(H2O)](NO3) (3). Compound (2) is a trinuclear hydroxo-centered complex with a central hydroxo group bridging the three nickel(II) ions. The [Ni3(μ3-OH)]5+ core is planar with the benzoylhydrazone ligands coordinated in the bis-bidentate [O(4),N(5)]-[N(61),O(63)] mode. The zinc(II) compound displays a BPT coordination geometry in which the BZLMH ligand acts in a tridentate fashion using N(5), N(61) and O(63) donor atoms. Fluorescence spectroscopic properties of benzoylhydrazone (BZLMH) are studied and the fluorescence band shift and changes in intensity is modulated by complexation with different metal ions (Ni2+, Zn2+ and Hg2+), so the binding is signaled such a possible cause. [Copyright &y& Elsevier]

Abstract: A series of mononuclear complexes with Co(II), Ni(II), Cu(II), Zn(II), Hg(II), Mo(VI) and Pd(II) containing the ligand derived from the 1:2 condensation of 2,6-diformyl-4-methylphenol and 5,6-diamino-1,3-dimethyluracil (hereafter denoted as BDFDAAU) were synthesized. The complexes were characterized by elemental analysis, thermogravimetry (TG) and differential scanning calorimetry (DSC), IR, 1H, 13C and 15N NMR, UV–visible–near IR (UV–VIS–NIR), EPR and magnetic measurements. The deprotonated ligand in the phenolic oxygen shows a symmetric tridentate coordination mode through the two azomethine nitrogen atoms and the phenolic oxygen atom whereas the coordination of the neutral ligand takes place through the phenolic oxygen atom and one azomethine nitrogen atom. In the Mo(VI) complex, the ligand is bideprotonated in the phenolic oxygen and an amino group from one uracil unit; so, the coordination mode changes again into an asymmetric way: phenolic oxygen atom, one azomethine nitrogen atom and the nitrogen atom from the deprotonated amino group. The antiproliferative behaviour against the five human tumor cell lines (human neuroblastoma NB69, human breast cancer MCF-7 and EVSA-T, human glioma H4 and human bladder carcinoma cell line ECV) suggested a modulator behaviour, according to the concentration, of cell growth due to their estrogen-like characteristics. [Copyright &y& Elsevier]

Abstract: New complexes of rhenium(I) with some 5-nitrosopyrimidines with general formula [ReCl(CO)3L] have been prepared and characterized by elemental analysis, conductivity measurements, IR and 1H, 13C and 15N NMR spectroscopic methods. The complexes appear to be monomeric and the pyrimidine ligands act in a neutral form. The structure of [ReCl(CO)3(DANU)]·CH3CN has been solved by X-ray diffraction. The coordination environment around the Re(I) may be described as a distorted octahedron in which the ligand behaves in a bidentate fashion through N5 and O4 atoms, making a five-membered chelate ring. The coordination sphere is completed with three carbonyl groups in fac-arrangement and one chlorine atom. The evaluation of the antiproliferative behavior against five human tumor cell lines (human breast cancer MCF-7 and EVSA-T, human neuroblastoma NB69, human glioma H4 and human bladder carcinoma cell line ECV) suggested a modulator behavior of cell growth at low concentrations due to their estrogenic-like characteristics. [Copyright &y& Elsevier]

The synthesis, spectroscopic (IR, 1H and 13C NMR, UV–Vis–NIR, EPR), magnetic measurements and biological studies of a number of complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Au(III) and Hg(II) of the Schiff base derived from the 1:2 condensation of 2,6-diformyl-4-methylphenol and 5-aminouracil, ((5-{[(3-{[(2,4-dioxopyrimidin-5(1H,3H)-yl)imino]methyl}-2-hydroxy-5-methylphenyl)methylene]amino}pyrimidine-2,4(1H,3H)-dione, hereafter denoted as BDF5AU) are reported. In all cases, the complexes appear to be monomeric. The deprotonated ligand in the phenolic oxygen atom shows a tridentate coordination mode through the two azomethine nitrogen atoms and the phenolic oxygen atom. The coordination of the neutral ligand takes place through the phenolic oxygen atom and one azomethine nitrogen atom and the carbonylic oxygen atom in fourth position of one uracil ring. The biological properties of some perchlorate complexes on the activity of some neutral, acid, basic and omega aminopeptidases (AP) are assayed, demonstrating a general inhibitory effect. Neutral and basic AP are mainly inhibited by Cu(II), Ni(II) and Cd(II) complexes, although tyrosyl-AP is activated by Zn(II) complex. Glutamyl-AP but not aspartyl-AP is inhibited by all the complexes assayed excepting Zn(II) complex. Finally, omega AP is inhibited by Ni(II) and Cd(II) complexes. [Copyright &y& Elsevier]

• Fluctuating asymmetry (FA) is a less invasive indicator of effect of stress. • Treatments had an effect on femoral pore but non on head shape FA. • A dissimilar degree of FA among treatments was found only in females. • FA may have a real potential as biomarker of population stress in wall lizards. The extensive use of pesticides in agricultural environments produces drastic effects on wildlife, hence the need for less invasive indicators of environmental stress to monitoring the impact of agriculture treatments on biological systems. Fluctuating asymmetry (FA), as measure of developmental instability, has recently been proposed as reliable biomarker of populations stress due to environmental disturbance. We investigate femoral pores (FP) and dorsal head shape (HS) traits in populations of the Italian wall lizard inhabiting agricultural environments to examine whether different pesticide exposures (conventional, organic and control) can cause distinctive degree of FA. High-resolution photographs of FP and HS were taken in the field with a digital camera. The number of FP were counted twice on both sides and HS was analysed using geometric morphometrics with 25 landmarks and 12 semilandmarks. Individuals under conventional management showed higher levels of FA compared to control ones, and females exhibited higher FA levels than males for the FP. However, no significant difference was found for the HS trait. Our study provided evidence that FA may have a real potential as biomarker of population stress in wall lizards, highlighting the importance in the choice of the experimental design and the traits adopted for estimating DI. [ABSTRACT FROM AUTHOR]

Maintaining body temperature is essential for the optimal performance of physiological functions. Ectotherms depend on external heat sources to thermoregulate. However, thermoregulation may be constrained by body condition and hydration state. Autotomy (i.e., the voluntary shed of a body part) evolved in various animal lineages and allowed surviving certain events (such as predator attacks), but it may affect body condition and volume/surface ratios, increase dehydration and constrain thermoregulation. In the framework of a general analysis of the evolution of autotomy, here we assessed the effects of tail loss on the thermal preferences and evaporative water loss rates (EWL) in the lizard Podarcis bocagei , integrating the thermal and hydric factors. We did not observe shifts in the thermal preferences of experimentally autotomized lizards when compared to the controls, which contradicted the hypothesis that they would raise preferred temperature to increase metabolic rates and accelerate regeneration. Evaporative water loss rates were also similar for tailed and tailless individuals, suggesting negligible increase of water loss through the injury and no specific ecophysiological responses after autotomy. Therefore, the changes observed in autotomized lizards in the field are to be considered primarily behavioural, rather than physiological, and thermoregulation could be secondarily affected by behavioural compensations for an increased predation risk after autotomy. Functional studies are necessary to understand how lizards' interaction with the environment is altered after autotomy, and further studies including different dehydration levels would be useful to fully understand the effect of water shortage on lizards' performance after caudal autotomy. • Caudal autotomy showed no effects on Podarcis bocagei's thermal preference. • Evaporative water loss rates were unaffected by caudal autotomy, suggesting a negligible desiccation through the injury. • Lack of short-to-medium term effects on ecophysiology suggest that shifts after autotomy are mainly behavioural. [ABSTRACT FROM AUTHOR]

Two polycyclic lumazine derivatives with different side chains (alkyl-acid and alkyl-ester chains) have been synthesized. Both novel bioinspired compounds exhibit interesting luminescent properties. Herein, the structural and optical properties of these compounds have been analyzed by single-crystal X-ray analysis, absorption, fluorescence and vibrational Raman spectroscopy together with DFT calculations. Their spectroscopic behavior depends on the five-fused core, which remains almost planar in the excited electronic state, and also on the nature of the side chain. In the solid phase, bathochromic shifts were observed with respect to solution for both molecules. These spectroscopic shifts were particularly notorious for the acid derivative and they might be related to the differences found in the molecular packing depending on the nature of the side chain. Two different theoretical strategies were employed to study the molecular packing in the crystalline state. Firstly, the energy of the S 0 →S 1 transition was calculated for a molecule surrounded by a cluster of neighboring molecules extracted from the crystal structure. Secondly, the lowest-energy electronic transitions were computed for different-size molecular clusters extracted from the crystal structure. Thus, the J-aggregate photophysical behavior experimentally observed in the solid phase, and the spectroscopic differences between both compounds, were explained on the basis of short-range excitonic coupling. These results provide valuable insights for the rational design of new bioinspired compounds with luminescent properties. Image 1 • Two novel bioinspired polycyclic lumazines have been presented showing interesting luminescent properties. • Photophysical properties of the acid derivative could be modified as a function of pH in aqueous solution. • J-aggregate photophysical features could be explained on the basis of the short-range excitonic coupling. [ABSTRACT FROM AUTHOR]

A series of Ni(II), Zn(II) and Cd(II) complexes with the Schiff base derived from the condensation 1:1 from pyridine-2-carboxaldehyde and 5,6-diamino-1,3-dimethyluracil (6-amino-1,3-dimethyl-5-[(pyridin-2-ylmethylidene)-amino]pyrimidine-2,4(1 H ,3 H )-dione, DAAUPic) were synthesized and subsequently characterized by means of elemental analysis, FT-IR, NMR and nine of them by X-ray diffraction. Except the [Zn(μ- O , O′ -AcO)( N 5 , N 6 , N 1F -DAAUPicH –1 )] 2 and [Cd( O , O′ -NO 3 )(μ- O 4 ,( N 5 , N 6 , N 1F )-DAAUPicH −1 )(H 2 O)] 2 ·2H 2 O dimers and the [Cd(μ- S , N -SCN)( N 5 , N 6 , N 1F -DAAUPicH −1 )] n chain-like polymer, all of them display monomeric molecular structures. The anticancer activity of compounds was also explored studying their effects on renin-angiotensin system (RAS)-regulating aminopeptidases on estrogen-dependent and triple negative breast cancer cell lines. At the concentrations used, some of the complexes showed different effects on (RAS) peptidases, which support the idea that their effects on cell growth/proliferation could be related to autocrine/paracrine regulatory functions of their corresponding peptide substrates. [ABSTRACT FROM AUTHOR]

The reactions of [RhCl(CO)(PPh 3 ) 2 ], [RhCl(CO) 2 ] 2 and [IrCl(CO)(PPh 3 ) 2 ] with different 5-nitrosopyrimidines afforded sixteen complexes which have been structurally characterized by elemental analysis, IR and NMR ( 1 H and 13 C) spectral methods and luminescence spectroscopy. The crystal and molecular structures of [Rh III Cl(VIOH − 1 ) 2 (PPh 3 )], [Rh III Cl(DVIOH − 1 ) 2 (PPh 3 )] and [Rh II (DVIOH − 1 ) 2 (PPh 3 ) 2 ] have been established from single crystal x-ray structure analyses. The three complexes are six-coordinated with both violurato ligands into an equatorial N5,O4-bidentate fashion, but with different mutually arrangements. Theoretical studies were driven on the molecular structure of [Rh III Cl(VIOH − 1 ) 2 (PPh 3 )] to assess the nature of the metal–ligand interaction as well as the foundations of the cis – trans ( 3L – 2L ) isomerism. An assortment of density functional (SOGGA11-X, B1LYP, B3LYP, B3LYP-D3 and wB97XD) has been used, all of them leading to a similar description of the target system. Thus, a topological analysis of the electronic density within AIM scheme and the study of the Mulliken charges yield a metal–ligand link of ionic character. Likewise, it has been proved that the cis – trans isomerism is mainly founded on that metal–ligand interaction with the relativistic effects playing a significant role. Although most of the compounds showed low direct toxicity against the human cell lines NB69 (neuroblastoma) and U373-MG (astroglioma), they differently modify in several ways the renin–angiotensin system (RAS)-regulating proteolytic regulatory enzymes aminopeptidase A (APA), aminopeptidase N (APN) and insulin-regulated aminopeptidase (IRAP). Therefore, these complexes could exert antitumor activity against both brain tumor types, acting through the paracrine regulating system mediated by tissue RAS rather than exerting a direct cytotoxic effect on tumor cells. [ABSTRACT FROM AUTHOR]

We have described that local tissue renin-angiotensin-system (RAS) is involved in tumor growth in a rat model of experimental glioma in vivo, through the modification of their corresponding local proteolytic regulatory enzymes. Thus, we have found a time-dependent significant decrease in aminopeptidase N (APN) and a significant increase in aminopeptidase A (APA) activities concomitantly with tumor growth in tumor tissue whereas no changes were found in circulating aminopeptidase activities; we suggested that angiotensin peptides may play an essential step in both tumor infiltration and associated angiogenesis. Here we analyze in vitro the antiproliferative efficacy, apoptotic properties and effects of three new disilver complexes containing E-6-(hydroxyimino)ethyl-1,3,7-trimethyllumazine (lumazine = pteridine-2,4(1H,3H)-dione) on RAS-regulating APA and APN specific activities in human neuroblastoma and glioma cell lines NB69 and U373-MG. Disilver compounds showed cytotoxicity against both cell lines, although their potency was different for each cell type. Furthermore, NB69 cells need higher concentrations of silver complexes than U373-MG cells to obtain a 50% growth inhibition. All compounds showed apoptotic effects, with U373-MG cells being more susceptible. The three silver complexes tested also show a dose-dependent inhibitory effect on APA activity in NB69 and U373-MG cells, although U373-MG cells are more sensitive. On the contrary, none of them showed effects on APN activity in NB69 neuroblastoma cells whereas the three compounds showed a dose-dependent stimulatory effect on APN activity in U373-MG glioma cells with a similar potency. Disilver complexes show specific antitumor activity against brain tumor cells acting through the paracrine regulating system mediated by local tissue RAS. [ABSTRACT FROM AUTHOR]

Abstract: Seventeen new palladium(II) complexes of general formulaes PdCl2L, PdCl(LH−1)(solvent) and PdCl2(PPh3)2L containing pyrimidine ligands derived from 6-amino-5-nitrosouracil and violuric acid have been prepared and characterized by elemental analysis, IR and NMR (1H and 13C) methods and, two of them, PdCl(DANUH−1)(CH3CN)]·½H2O and [PdCl(2MeOANUH−1)(CH3CN)] by X-ray single-crystal diffraction (DANU: 6-amino-1,3-dimethyl-5-nitrosouracil; 2MeOANU: 6-amino-2-methoxy-5-nitroso-3H-pyrimidin-4-one). The coordination environment around palladium is nearly square planar in the two compounds with different supramolecular arrangements. Crystallographic and spectral data are consistent with a bidentate coordination mode through N5 and O4 atoms when the ligands act in neutral form and N5 and N6 atoms in the monodeprotonated ones. The cytotoxicity of the complexes against human neuroblastoma (NB69) and human glioma (U373-MG) cell lines has been tested showing a considerable antiproliferative activity. Also, the study of the effects of palladium(II) complexes on the renin–angiotensin system (RAS) regulating proteolytic regulatory enzymes aminopeptidase A (APA), aminopeptidase N (APN) and insulin-regulated aminopeptidase (IRAP) shows a strong dependence on the compound tested and the tumoral cell type, also affecting different catalytic routes; the compounds affect in a different way the activities of enzymes of the RAS system, changing their functional roles as initiators of cell proliferation in tumors as autocrine/paracrine mediators. [Copyright &y& Elsevier]

Abstract: The synthesis and molecular and supramolecular structures of the compound (6-amino-1-methyl-5-nitrosouracilato-N3)-triphenylphosphine-gold(I) with interesting abilities to inhibit tumor growth in an animal model of experimental glioma are reported. Thus, its antitumor properties, effects on both enzyme and non-enzyme antioxidant defense systems and the response of several biochemical biomarkers have been analyzed. After seven days of treatment, the gold compound decreased the tumor growth to ca. one-tenth and reduced oxidative stress biomarkers (thiobarbituric acid-reactive substances (TBARS) and protein oxidation levels) compared to animals treated with the vehicle. Also, gold compound maintained non-enzyme antioxidant defense systems as in non-tumor animals and increased enzyme antioxidant defenses, such as superoxide dismutase and glutathione peroxidase activities, and decreased catalase activity. Analysis of serum levels of electrolytes, nitrogenous compounds, glucose, lipids, total protein, albumin, transaminases and alkaline phosphatase indicated that gold compound treatment showed few adverse effects, while effectively inhibiting tumor growth through mechanisms that involved endogenous antioxidant defenses. [Copyright &y& Elsevier]

Abstract: The symmetric diazine derived from 6-acetyl-1,3,7-trimethylpteridine-2,4(1H,3H)-dione, (6,6′,1,1′-(hydrazine-1,2-diylidene) bis (ethan-1-yl-1-ylidene) bis (1,3,7-trimethylpteridine-2,4(1H,3H)-dione), DHzD) has been prepared and reacted with ReCl(CO)5 and AgClO4 to give binuclear complexes with formula [Re2Cl2(CO)6(DHzD)]·2CH3CN and [Ag2(DHzD)2](ClO4)2·7H2O. The XRD single-crystal results indicate two quite different binuclear modes depending on the number of ligands and the counteranion coordinative capacities. Thus, the dirhenium complex consists in two fac-ReCl(CO)3 + units attached to the N5–O4 bidentate sites from both pteridine moieties of the Z,Z′ isomer of the ligand (Re–O, 2.185(5) and Re–N5, 2.225(6)Å). The disilver complex displays two crystallographically independent but practically equivalent 3+3-coordinated silver centers to N61, N5 and O4 atoms from both DHzD ligands (E,E′ isomer); distances Ag–N range between 2.31 and 2.48Å, whereas oxygen atoms are weaker bonded (2.65–2.82Å). In the molecular units there are not M–M bonds, both metal atoms lying farther than the sum of Van der Waals’ radii (Re–Re, 7.959(5)Å; Ag–Ag, 4.073(5) Å). [Copyright &y& Elsevier]

Abstract: The rise of molecular techniques in the study of evolutionary histories has resulted in a gradual abandonment of morphological characters as the only sources of phylogenetic inference. However, morphological characters may be valuable for phylogenetic reconstruction, especially for tracking adaptive changes across phylogeographic groups defined by genetic markers. We examined the discriminative power of morphological characters between four mitochondrial clades covering almost the entire distribution area of the smooth snake Coronella girondica in the Western Mediterranean. We detected three characters showing sexual dimorphism (relative tail length, number of ventral and of subcaudal scale counts) and, more interestingly, two characters (number of subcaudal and of dorsal rows) displaying interclade differences. Almost all C. girondica examined had 21 dorsal rows except those from a narrow coastal belt in the south-eastern Iberian Peninsula, which had 19 dorsal rows. The distribution of these specimens matches a mitochondrial clade that originated approximately 1.4–2.0 million years ago. Both of these morphological characters support a Betic lineage with a rather well-defined contact zone with the other Iberian lineage, which has been maintained even without the existence of current geographic barriers. The long-term survival of the Betic lineage throughout the Pleistocene climatic oscillations suggests a systematic revision within C. girondica. [Copyright &y& Elsevier]

Abstract: The XRD structure of two seven-coordinated Mn(II) complexes with the formula [Mn(phen)(nicot)(NO3)(H2O)]·EtOH·H2O (1) and [Mn(phen)(NO3)2(H2O)] (2) are reported. The 2,9-dimethyl-1,10-phenanthroline, nitrato and nicotinato anions act as bidentate ligands, with Mn–N distances of 2.21–2.29Å and Mn–O distances of 2.17–2.40Å. In both compounds, the water molecule seems to be the strongest coordinated ligand, with bond distances of 2.139(2)Å in 1 and 2.195(2)Å in 2. The average ratio between coordinated unidentate and bidentate bond lengths less than the unity justifies, from an energetical point of view, the shape of the coordination polyhedra. In the structure of 1, the coordination polyhedron may be best-described as a distorted pentagonal bipyramid with a nitrogen from phenanthroline and the water molecule occupying the apical sites. The polyhedron shape for 2 is close to a square-capped trigonal prism, the capping site being occupied by the water molecule. The crystal structures are built by H-bonded bidimensional sheets piled up by π–π stacking of the partially interpenetrated aromatic moieties of adjacent layers. [Copyright &y& Elsevier]

Abstract: Three new Cd(II) complexes with the Schiff base ligand derived from the condensation 1+2 of 2,6-diacetylpyridine and 5,6-diamino-1,3-dimethyluracil have been “in template” synthesized. The molecular structures of complexes were determined by single-crystal X-ray diffraction. The metal center shows a very distorted mer-bis-tridentate CdN6 octahedral geometry as consequence of the reduced bite angles of the ligand and the existence of long-distanced interactions with donor atoms in the neighbourhood. The luminescent properties of complexes in CH3CN solution were investigated showing the emission energies depend on the uracil part of the ligand. The evaluation of their biological properties against C6 glioma cell line indicates that cadmium(II) complexes could be an interesting tools to treat drug-resistant brain tumors. [Copyright &y& Elsevier]

Abstract: The human exploitation of land resources (land use) has been considered the major factor responsible for changes in biodiversity within terrestrial ecosystems given that it affects directly the distribution of the fauna. Reptiles are known to be particularly sensitive to habitat change due to their ecological constraints. Here, the impact of land use on reptile diversity was analysed, choosing Catalonia (NE Iberia) as a case study. This region provides a suitable scenario for such a biogeographical study since it harbours: 1) a rich reptile fauna; 2) a highly diverse environment showing strong variation in those variables usually shaping reptile distributions; and 3) good species distribution data. Potential species richness was calculated, using ecological modelling techniques (Ecological Niche Factor Analysis – ENFA). The subtraction of the observed from the potential species richness was the dependent variable in a backwards multiple linear regression, using land use variables. Agriculture was the land use with the strongest relation with the non-fulfilment of the potential species richness, indicating a trend towards a deficit of biodiversity. Deciduous forest was the only land use negatively related with the subtracted species richness. Results indicate a clear relationship between land use and biodiversity at a mesoscale. This finding represents an important baseline for conservation guidelines within the habitat change framework because it has been achieved at the same spatial scale of chorological studies and management policies. [Copyright &y& Elsevier]