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In seasonal environments, many organisms evolve strategies such as diapause to survive stressful periods. Understanding the link between habitat stability and diapause strategy can help predict population’s survival in a changing world. Freshwater organisms may survive periods of drought or freezing only with the help of durable resting stages. The frequency and extent of drought or freezing vary strongly among habitats and are predicted to change as a consequence of climate change raising questions about an organism’s ability to cope with different forms of stress. Using Daphnia magna as a model system, we tested resting stages from different populations for their ability to cope with stress during diapause. The combination of elevated temperatures and wet conditions during diapause shows to prevent hatching altogether. In contrast, hatching is relatively good after a dry and warm diapause, but declines with rising temperatures, while time to hatching increases. Resting stages produced by populations from summer-dry habitats perform slightly, but consistently, better at higher temperatures and dryness, supporting the local adaptation hypothesis. Considering that temperatures and summer droughts are projected to increase in upcoming years, it is fundamental to know how resting stages resist stressful conditions so as to predict and protect the ecological functioning of freshwater ecosystems.

Environmental fluctuations often select for adaptations such as diapause states, allowing species to outlive harsh conditions. The natural sugar trehalose which provides both cryo- and desiccation-protection, has been found in diapause stages of diverse taxa. Here, we hypothesize that trehalose deposition in resting stages is a locally adapted trait, with higher concentrations produced in harsher habitats. We used resting stages, produced under standardized conditions, by 37 genotypes of Daphnia magna collected from Western Palaearctic habitats varying in their propensity to dry in summer and freeze in winter. Resting eggs produced by D. magna from populations from summer-dry habitats showed significantly higher trehalose than those from summer-wet habitats, suggesting that trehalose has a protective function during desiccation. By contrast, winter-freezing did not explain variation in trehalose content. Adaptations to droughts are important, as summer dryness of water bodies is foreseen to increase with ongoing climate change.

Gnathiid isopods are marine ectoparasites that feed on the blood of fishes that have been implicated as vectors of blood parasites, with transmission possibly occurring through biting during their parasitic life-stages, or through ingestion by fishes. However, evidence for their role as vectors is limited, reflecting the small number of research groups working on them. Here, we used a molecular barcode approach to identify fish hosts and apicomplexan parasites in free-living gnathiids from the eastern Caribbean Sea, with the goal of further evaluating their potential role as reservoirs and/or vectors for these parasites. Apicomplexa were only identified in 8% of the Gnathia analyzed, and in four cases we could identify both Apicomplexa and fish host DNA. The results further suggest that Gnathia spp. in this region may serve as reservoirs for Apicomplexa, but whether they are vectors for this parasite remains uncertain.

According to the World Health Organization, cancer is one of the leading causes of morbidity and mortality worldwide. The previously estimated 14 million new cases in the year of 2012 are expected to rise, yearly, over the following 2 decades. Among women, breast cancer is the most common one. In 2012, almost 1.7 million people were diagnosed worldwide and half a million died from the disease. Despite having several treatments available, from surgery to chemotherapy, most of these treatments have severe adverse effects. Chemotherapy has a narrow therapeutic window and requires high dosage treatment in patients with advanced-stage cancers and further need innovative treatment strategies. Although methotrexate (MTX) is not a first line drug used against breast cancer, however, it might be valuable to fight the disease. MTX is an effective and cheap drug that might impair malignant growth without irreversible damage to normal tissues. Nevertheless, while MTX does present some disadvantages including poor solubility and low permeability, several strategies are being used to discover and provide novel and effective targeted treatment against breast cancer. In this review, we analyze the chemotherapy of breast cancer and its relationship with drug MTX.

The phylogenetic and systematic relationships of the reduced limbed lizards of the genus Bachia are poorly understood. Here, we investigate the eastern Caribbean Bachia assigned to the B. heteropa and B. flavescens groups, whose members are characterized by a band of hexagonal or quadrangular scales on the dorsum, respectively. The polytypic Bachia heteropa is redefined, and the previous subspecies in the Grenadines (Bachia heteropa alleni) and Trinidad (B. h. trinitatis) are demonstrated to be species-level lineages. One new species of hex-scaled Bachia was formerly assigned intergrade status between B. heteropa and Bachia trinitatis. Here, it is described as a new species from Caripito, Venezuela. Bachia h. heteropa, B. h. lineata, and B. h. marcelae are elevated to species status. The Tobago species formerly considered a member of the Bachia flavescens species group is described as a new species. In this paper, we increase the number of species in the genus Bachia from 25 to 31 with the description of two new species and the elevation of four previously described species from the synonymy of Bachia heteropa. This work will greatly improve the understanding of the systematics and evolution of Bachia in the eastern Caribbean.

Biological therapies, such as recombinant proteins, are nowadays amongst the most promising approaches towards precision medicine. One of the most innovative methodologies currently available aimed at improving the production yield of recombinant proteins with minimization of costs relies on the combination of in silico studies to predict and deepen the understanding of the modified proteins with an experimental approach. The work described herein aims at the design and production of a biomimetic vector containing the single-chain variable domain fragment (scFv) of an anti-HER2 antibody fragment as a targeting motif fused with HIV gp41. Molecular modeling and docking studies were performed to develop the recombinant protein sequence. Subsequently, the DNA plasmid was produced and HEK-293T cells were transfected to evaluate the designed vector. The obtained results demonstrated that the plasmid construction is robust and can be expressed in the selected cell line. The multidisciplinary integrated in silico and experimental strategy adopted for the construction of a recombinant protein which can be used in HER2+-targeted therapy paves the way towards the production of other therapeutic proteins in a more cost-effective way.

In this work we report on the development of Giant Magnetoresistive (GMR) sensors for off-line current measurements in standard integrated circuits. An ASIC has been specifically designed and fabricated in the well-known AMS-0.35 μm CMOS technology, including the electronic circuitry for sensor interfacing. It implements an oscillating circuit performing a voltage-to-frequency conversion. Subsequently, a fully CMOS-compatible low temperature post-process has been applied for depositing the GMR sensing devices in a full-bridge configuration onto the buried current straps. Sensitivity and resolution of these sensors have been investigated achieving experimental results that show a detection sensitivity of about 100 Hz/mA, with a resolution of about 5 μA.

Gnathiid isopods are marine ectoparasites that feed on the blood of fishes that have been implicated as vectors of blood parasites, with transmission possibly occurring through biting during their parasitic life-stages, or through ingestion by fishes. However, evidence for their role as vectors is limited, reflecting the small number of research groups working on them. Here, we used a molecular barcode approach to identify fish hosts and apicomplexan parasites in free-living gnathiids from the eastern Caribbean Sea, with the goal of further evaluating their potential role as reservoirs and/or vectors for these parasites. Apicomplexa were only identified in 8% of the Gnathia analyzed, and in four cases we could identify both Apicomplexa and fish host DNA. The results further suggest that Gnathia spp. in this region may serve as reservoirs for Apicomplexa, but whether they are vectors for this parasite remains uncertain.

The broadstripe cleaning goby Elacatinus prochilos has two alternative ecotypes: sponge-dwellers, which live in large groups and feed mainly upon nematode parasites; and coral-dwellers, which live in small groups or in solitude and behave as cleaners. Recent studies focusing on the skin and gut microbiomes of tropical fish showed that microbial communities are influenced mainly by diet and host species. Here we compare the skin and gut microbiomes of the Caribbean broadstripe cleaning goby Elacatinus prochilos alternative ecotypes (cleaners and non-cleaners) from Barbados and predict that different habitat use and behavior (cleaning vs non-cleaning) will translate in different microbial assemblages between the two ecotypes. We sequenced the microbial 16S rRNA V4 region and performed amplicon sequence variant (ASV) analysis using the dada2 pipeline implemented in the QIIME 2 bioinformatic platform. We used Linear Regression and permutational multivariate analysis of variance to test whether differences in alpha- and beta-diversities, respectively, could be attributed to ecotype. We found significant differences in both alpha- and beta-diversity of skin and gut microbiomes belonging to different ecotypes. Importantly, the skin microbiome of obligate cleaners is more diverse (alpha-diversity estimates) and harbours a significantly higher proportion and prevalence of potential fish pathogens. Likewise, potential pathogens were also more prevalent in the gut of coral dwellers. We suggest that habitat use, diet, but also direct contact with potential diseased clientele during cleaning, could be the cause for this pattern.

The common wall lizard has been widely introduced across Europe and overseas. We investigated the origin of putatively introduced Podarcis muralis populations from two southern Europe localities: (i) Ljubljana (Slovenia), where uncommon phenotypes were observed near the railway tracks and (ii) the port of Vigo (Spain), where the species was recently found 150 km far from its previously known range. We compared cytochrome-b mtDNA sequences of lizards from these populations with published sequences across the native range. Our results support the allochthonous status and multiple, long-distance origins in both populations. In Ljubljana, results support two different origins, Serbia and Italy. In Vigo, at least two separate origins are inferred, from western and eastern France. Such results confirm that human-mediated transport is promoting biological invasion and lineage admixture in this species. Solid knowledge of the origin and invasion pathways, as well as population monitoring, is crucial for management strategies to be successful.

Genetic diversity within partial 18S rRNA sequences from Hepatozoon protozoan parasites from domestic cats in South Africa was assessed and compared against published data to assess global biogeographic patterns. Multiple distinct haplotypes of Hepatozoon felis were identified, as well as an unrelated Hepatozoon lineage. Hepatozoon felis genetic diversity globally is very high, indicating a likely complex of species. The recently described Hepatozoon apri from wild boars is closely related to some lineages of H. felis. Sarcocystis and Babesia parasites were also detected. Since Hepatozoon felis is apparently a species complex, potential differences between genetically distinct forms need to be assessed. The finding of an unrelated Hepatozoon indicates that felids can be infected by more species of Hepatozoon than currently known, and that trophic interactions may increase the number of Hepatozoon species found in carnivores. Genetic screening again is demonstrated to identify previously unrecognised parasites from vertebrate hosts.

Hemosporidians are a monophyletic group of protozoan parasites infecting all terrestrial vertebrate orders. Although Plasmodium is the most studied genus within the Haemosporidia, this research effort is heavily biased toward mammal and bird hosts. We screened 205 specimens of at least 18 reptile species from Brazil using a partial mitochondrial cytochrome b gene marker. Positive samples were sequenced and included in a phylogenetic assessment. Four positive PCR products matched others identified as Plasmodium using BLAST from 3 different host species, Ameiva ameiva, Tropidurus hispidus, and Hemidactylus mabouia. Recovery of similar haplotypes in the native T. hispidus and exotic H. mabouia (99.9%) indicate potential host-switching.

Tissue samples from wildlife from South Africa were opportunistically collected and screened for haemoprotozoan parasites using nonspecific PCR primers. Samples of 127 individuals were tested, comprising over 50 different species. Haemogregarines were the most commonly identified parasites, but sarcocystids and piroplasmids were also detected. Phylogenetic analyses estimated from the 18S rDNA marker highlighted the occurrence of several novel parasite forms and the detection of parasites in novel hosts. Phylogenetic relationships, which have been recently reviewed, appear to be much more complex than previously considered. Our study highlights the high diversity of parasites circulating in wildlife in this biodiverse region, and the need for further studies to resolve taxonomic issues.

Cartilaginous fishes are the oldest jawed vertebrates and are also reported to be the hosts of some of the most basal lineages of Cestoda and Aporocotylidae (Digenea) parasites. Recently a phylogenetic analysis of the coccidia (Apicomplexa) infecting marine vertebrates revealed that the lesser spotted dogfish harbours parasite lineages basal to Eimeria Schneider, 1875 and the group formed by Schellackia Reichenow, 1919, Lankesterella Ames, 1923, Caryospora Leger, 1904 and Isospora Schneider, 1881. In the present study we have found additional lineages of coccidian parasites infecting the cownose ray Rhinoptera bonasus Mitchill and the blue shark Prionace glauca Linnaeus. These lineages were also found as basal to species from the genera Lankesterella, Schellackia, Caryospora and Isospora infecting higher vertebrates. These results confirm previous phylogenetic assessments and suggest that these parasitic lineages first evolved in basal vertebrate hosts (i.e. Chondrichthyes), and that the more derived lineages infect higher vertebrates (e.g. birds and mammals) conforming to the evolution of their hosts. We hypothesise that elasmobranchs might host further ancestral parasite lineages harbouring unknown links of parasite evolution.

Less than thirty years after the giant magnetoresistance (GMR) effect was described, GMR sensors are the preferred choice in many applications demanding the measurement of low magnetic fields in small volumes. This rapid deployment from theoretical basis to market and state-of-the-art applications can be explained by the combination of excellent inherent properties with the feasibility of fabrication, allowing the real integration with many other standard technologies. In this paper, we present a review focusing on how this capability of integration has allowed the improvement of the inherent capabilities and, therefore, the range of application of GMR sensors. After briefly describing the phenomenological basis, we deal on the benefits of low temperature deposition techniques regarding the integration of GMR sensors with flexible (plastic) substrates and pre-processed CMOS chips. In this way, the limit of detection can be improved by means of bettering the sensitivity or reducing the noise. We also report on novel fields of application of GMR sensors by the recapitulation of a number of cases of success of their integration with different heterogeneous complementary elements. We finally describe three fully functional systems, two of them in the bio-technology world, as the proof of how the integrability has been instrumental in the meteoric development of GMR sensors and their applications.

Species that are able to solve novel problems through social learning from either a conspecific or a heterospecific may gain a significant advantage in new environments. We tested the ability of a highly successful invasive species, the Italian wall lizard Podarcis sicula , to solve a novel foraging task when social information was available from both a conspecific and an unfamiliar heterospecific ( Podarcis bocagei ). We found that Italian wall lizards that had access to social information made fewer errors, regardless of whether the demonstrator was a conspecific or a heterospecific, compared to Italian wall lizards that individually learnt the same task. We suggest that social learning could be a previously underappreciated, advantageous mechanism facilitating invasions.

The effects of ice ages on speciation have been well documented for many European and North American taxa. In contrast, very few studies have addressed the consequences of such environmental and topographical changes in North East Asian species. More precisely, the Korean Peninsula offers a unique model to assess patterns and processes of speciation as it hosts the northern- and eastern-most distribution limit of some widespread Asian taxa. Despite this, studies addressing phylogeographic patterns and population genetics in the peninsula and surrounding countries are few and studies for most families are lacking. Here we inferred the phylogenetic relationships of the common toad (Bufo gargarizans) from South Korea and their North East Asian counterpart populations, based on mitochondrial data. KoreanB. gargarizansGenBank BLASTs matched few individuals from nearby China, but the presence of a Korean clade suggests isolation on the Korean Peninsula, previous to the last glacial maximum, linked to sea level resurgence. Molecular clock calibrations within this group were used to date the divergence between clades and their relationship to paleo-climatic events in the area. Lack of genetic structure among South Korean populations and strong homogeneity between the Korean and some Chinese localities suggest weak isolation and recent expansion. Geographical projection of continuous coalescent maximum-clade-credibility trees shows an original Chinese expansion towards the Korean Peninsula through the Yellow Sea circa two million years ago with colonisation events dating circa 800 thousand years ago (K. y. a.). Following this colonisation, the data point to outgoing Korean Peninsula dispersal events throughout different periods, towards the North through land, and West through land bridge formations over the Yellow Sea during sea level falls. In accordance, demographic analyses revealed a population expansion in the Koran Peninsula circa 300 K. y. a., likely attributed to glacial cycle fluctuations.