Carbapenem-resistant
(CR-KP) represents an emerging threat to public health. CR-KP infections result in elevated morbidity and mortality. This fact, coupled with their global dissemination and ...increasingly limited number of therapeutic options, highlights the urgency of novel antimicrobials. Innovative strategies linking genome-wide interrogation with multi-layered metabolic data integration can accelerate the early steps of drug development, particularly target selection. Using the BioCyc ontology, we generated and manually refined a metabolic network for a CR-KP,
Kp13. Converted into a reaction graph, we conducted topological-based analyses in this network to prioritize pathways exhibiting druggable features and fragile metabolic points likely exploitable to develop novel antimicrobials. Our results point to the aptness of previously recognized pathways, such as lipopolysaccharide and peptidoglycan synthesis, and casts light on the possibility of targeting less explored cellular functions. These functions include the production of lipoate, trehalose, glycine betaine, and flavin, as well as the salvaging of methionine. Energy metabolism pathways emerged as attractive targets in the context of carbapenem exposure, targeted either alone or in conjunction with current therapeutic options. These results prompt further experimental investigation aimed at controlling this highly relevant pathogen.
A detailed analysis of low power (100 kW) solar-driven Rankine cycles in the medium temperature range has been carried out. Toluene, octamethylcyclotetrasiloxane (D4) and hexamethyldisiloxane (MM) ...has been considered as working fluids of organic Rankine cycle (ORC). Direct solar vapor generation configuration of solar ORC has been analysed and characterized with LS3 and IND300 parabolic trough collector (PTC) models. The analysis has been carried out for condensation temperatures in the ORC between 35ºC and 115ºC so that thermal power rejected can be used in different ways related to desalination processes (preheating of reverse osmosis feed, heating of feed of conventional or membrane distillation processes). The results obtained indicate a great importance of the regeneration process and such that is greater in the case of D4 and MM than toluene. On the other hand, vapor superheating implies an ORC thermal efficiency grown only if is accomplished by regeneration process with minimum certain values of recuperator effectiveness. From global efficiency point of view, in a 100 kW gross mechanical output solar ORC with identical condensation temperatures toluene presents the best behaviour follows by D4 and MM. The difference between toluene and D4 and MM is particularly important if the regeneration process is not considered. In a system with LS3 PTC an a recuperator´s effectiveness of 0.8, global efficiency values up to 22.3%, 19.3% and 18.3% with toluene, D4 and MM as working fluids can be reached respectively if condensation temperature is set to 35ºC. These values came down to 15.3%, 12.8% and 11% respectively if condensation temperature is set to 115ºC. If solar system is consisting of IND300 PTC global efficiency values are smaller than previously mentioned. In that case, global efficiency values up to 17.3%, 15.7% and 15% with toluene, D4 and MM as working fluids can be reached respectively if condensation temperature is set to 35ºC. With a condensation temperature of 115ºC the values are 11%, 10% and 8.8%.
Hairy armadillos constitute an ecologically homogeneous and morphologically similar group with currently 5 species classified in the subfamily Euphractinae. Among them, the Andean hairy armadillo ...Chaetophractus nationi (Xenarthra, Cingulata, Dasypodidae) is a small, endangered armadillo that has long been suspected to represent a high-altitude variant of Chaetophractus vellerosus. Here, we report the 1st phylogenetic systematics assessment of hairy armadillos using morphological and molecular analyses of all described species with focus on the status of the Andean hairy armadillo. Multivariate analyses of shape variation based on 3-dimensional landmark coordinates of skulls allowed a clear differentiation of each species with the exception of C. vellerosus and C. nationi, within which only a latitudinal and/or altitudinal gradient in size was apparent. Moreover, analyses of mitochondrial DNA control region (D-loop) revealed a single C. nationi haplotype that appeared to be identical with a C. vellerosus haplotype from Argentina. Identical sequences in C. vellerosus and C. nationi were also observed for 3 of the 5 non-coding nuclear markers investigated. Based on these data, we propose that C. nationi should be considered as a synonym of C. vellerosus. However, this taxonomic change should not preclude the protection of the high-altitude Bolivian populations that are steadily declining because of their overexploitation for traditional purposes. Finally, phylogenetic analyses of euphractine armadillos based on a combination of 6 non-coding nuclear markers and 2 nuclear exons suggest the paraphyly of the genus Chaetophractus, with C. vellerosus being more closely related to Zaedyus pichiy than to C. villosus.
Androgens play a critical role in the development of the male reproductive system, including the positioning of the gonads. It is not clear, however, which developmental processes are influenced by ...androgens and what are the target tissues and cells mediating androgen signaling during testicular descent. Using a Cre-loxP approach, we have produced male mice (GU-ARKO) with conditional inactivation of the androgen receptor (Ar) gene in the gubernacular ligament connecting the epididymis to the caudal abdominal wall. The GU-ARKO males had normal testosterone levels but developed cryptorchidism with the testes located in a suprascrotal position. Although initially subfertile, the GU-ARKO males became sterile with age. We have shown that during development, the mutant gubernaculum failed to undergo eversion, a process giving rise to the processus vaginalis, a peritoneal outpouching inside the scrotum. As a result, the cremasteric sac did not form properly, and the testes remained in the low abdominal position. Abnormal development of the cremaster muscles in the GU-ARKO males suggested the participation of androgens in myogenic differentiation; however, males with conditional AR inactivation in the striated or smooth muscle cells had a normal testicular descent. Gene expression analysis showed that AR deficiency in GU-ARKO males led to the misexpression of genes involved in muscle differentiation, cell signaling, and extracellular space remodeling. We therefore conclude that AR signaling in gubernacular cells is required for gubernaculum eversion and outgrowth. The GU-ARKO mice provide a valuable model of isolated cryptorchidism, one of the most common birth defects in newborn boys.
Although there are specific and general digital scanning guidelines depending on the system used, it is important to have the necessary flexibility in the acquisition of three-dimensional (3D) images ...to adapt to any clinical situation without affecting accuracy.
The purpose of this in vitro study was to identify and compare the scanning strategy with the greatest accuracy, in terms of trueness and precision, of four intraoral scanners in the impression of a complete dental arch.
Four digital scanners were evaluated with a 3D measuring software, using a highly accurate reference model obtained from an industrial scanner as a comparator. Four scanning strategies were applied 10 times on a complete maxillary arch cast inside a black methacrylate box. The data were statistically analyzed using one-way analysis of variance (ANOVA) and post hoc comparisons with Tamhane T2 test.
The trueness of the Trios and iTero system showed better results with strategy "D," Omnicam with strategy "B," and True Definition with strategy "C". In terms of precision, both iTero and True Definition showed better results with strategy "D", while Trios showed best results with strategy "A" and Omnicam with strategy "B". There were significant differences between the scanning strategies (p<0.05) with the iTero scanner, but not with the other scanners (p>0.05).
The digital impression systems used in the experiment provided sufficient flexibility for the acquisition of 3D images without this affecting the accuracy of the scanner.
•Pollination of oilseed rape, sunflower, pears and pumpkin was investigated in Europe.•Average harvestable mass was 2.8 % lower because of pollination limitation.•Highest pollination limitation was ...found for sunflowers (8%) and oilseed rape (6%).•No evidence of pollination limitation was found for pears and pumpkins.•Number of pollinator visits did not correspond with levels of pollination limitation.
Pollination services to crops may be worsening because of declines in farmland pollinators, but the consequences for yields have been uncertain. We therefore investigated pollination limitation in four entomophilous crops (oilseed rape, sunflower, pears and pumpkin) by quantifying the difference in harvestable mass between open-pollinated and saturation-pollinated (hand-pollinated) flowers. We also examined whether pollination limitation in the four crops was associated with the number of flower visits by insects. Across 105 commercial fields in six European countries, the average decrease in harvestable mass due to pollination limitation was 2.8 % (SE = 1.15). Among crops, the highest decreases were in sunflowers (8%) and in one of three oilseed rape production regions (6%). We observed substantial variation among crops in the numbers of insect visits received by flowers, but it did not significantly correspond with the levels of pollination limitation. Our results suggest that yields in these crops were not severely pollination-limited in the regions studied and that other factors besides visitation by pollinators influenced the degree of pollination limitation.
Armadillos are considered important reservoir hosts for
Trypanosoma cruzi
, the causative agent of Chagas disease
.
The first report of
T. cruzi
infection in pichis (
Zaedyus pichiy
), a small ...armadillo species endemic to central Argentina and Chile, dates back to 1935. However, more recent reports on
T. cruzi
in this species are scarce. The objective of this study was to assess
T. cruzi
infection and parasite load in
Z. pichiy
from Mendoza Province, an area endemic to human Chagas disease. Blood samples were obtained in 2014–2016 from pichis from Lavalle (low Monte), Malargüe (Patagonian steppe), and San Carlos (ecotone) departments, Mendoza Province, Argentina. The detection and quantification of
T. cruzi
was performed through qPCR amplification using satellite primers. Of the 265 analyzed samples, 201 (76%) were positive for
T. cruzi
. Parasite loads varied between < 0.1–55.8 parasite-equivalents/mL (par-eq/mL), with a median of 1.1 par-eq/mL in quantifiable samples. The prevalence was similar in Malargüe and Lavalle (85–94%), but significantly lower in pichis from San Carlos (50%). Animals from Lavalle captured after hibernation had significantly higher parasite loads (median 2.0 par-eq/mL). In Malargüe,
T. cruzi
infection and parasite loads were significantly lower before than after hibernation in 2016. The high prevalence and low median parasite load suggest a chronic and persistent infection of
T. cruzi
in pichis. Regional differences and a marked increase in precipitation during 2015–2016 could have influenced annual and seasonal infection rates of this vector-borne disease.
The pichi (Zaedyus pichiy; Cingulata: Chlamyphoridae) is an armadillo whose ectoparasite fauna is composed of ticks and fleas. Fleas were collected from 218 pichis in southern Mendoza, Argentina, in ...summer and winter of 2015 and 2016. Prevalences were analyzed and differences in the intensities of the total number of fleas related to host (age, sex, weight, size and physical condition) and environment-related (seasonality and year) factors evaluated. Phthiropsylla agenoris was the only species found. Intensities of fleas were higher in 2015, in juveniles, and in males. Individuals with poor physical condition were more parasitized than those with good or normal body condition. The main explanatory variable was sampling year. This factor was directly associated with precipitation. The extreme conditions and heavy rains during the El Niño event in 2015/2016 led to environmental changes that seem to have severely affected the life cycle of fleas.
1. Enhancing key floral resources is essential to effectively mitigate the loss of pollinator diversity and associated provisioning of pollination functions in agro-ecosystems. However, effective ...floral provisioning measures may diverge among different pollinator conservation targets, such as the conservation of rare species or the promotion of economically important crop pollinators. We examined to what extent such diverging conservation goals could be reconciled. 2. We analysed plant-bee visitation networks of 64 herbaceous semi-natural habitats representing a gradient of plant species richness to identify key resource plants of the three distinct conservation target groups: rare bees (of conservation concern), dominant wild croppollinating bees and managed crop-pollinating bees (i.e. honeybees). 3. Considering overall flower visitation, rare bees tended to visit nested subsets of plant species that were also visited by crop pollinators (46% and 77% nestedness in the dissimilarity between rare bees and wild crop pollinators or managed honeybees respectively). However, the set of preferred plant species, henceforth 'key plant species' (i.e. those species disproportionately more visited than expected according to their floral abundance) was considerably more distinct and less nested among bee target groups. 4. Flower visits of all bee target groups increased with plant species richness at a similar rate. Importantly, our analyses revealed that an exponential increase in the flower abundance of the identified key plant species and complementarity in the bee visitation pattern across plant species — rather than total flower abundance — were the major drivers of these relationships. 5. Synthesis and applications. We conclude that the multiple goals of preserving high bee diversity, conserving rare species and sustaining crop pollinators can be reconciled if key plant species of different target groups are simultaneously available. This availability is facilitated by a high floral resource complementarity in the plant community. The list of identified key resource plant species we provide here can help practitioners such as land managers and conservationists to better design and evaluate pollinator conservation and restoration measures according to their goals. Our findings highlight the importance of identifying and promoting such plant species for pollinator conservation in agricultural landscapes.
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