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The remarkable performance of Convolutional Neural Networks (CNNs) has increased their use in real-time systems and devices with limited resources. Hence, compacting these networks while preserving accuracy has become necessary, leading to multiple compression methods. However, the majority require intensive iterative procedures and do not delve into the influence of the used data. To overcome these issues, this paper presents several contributions, framed in the context of e x plainable Artificial Intelligence (xAI): (a) two filter pruning methods for CNNs, which remove the less significant convolutional kernels; (b) a fine-tuning strategy to recover generalization; (c) a layer pruning approach for U-Net; and (d) an explanation of the relationship between performance and the used data. Filter and feature maps information are used in the pruning process: Principal Component Analysis (PCA) is combined with a next-convolution influence-metric, while the latter and the mean standard deviation are used in an importance score distribution-based method. The developed strategies are generic, and therefore applicable to different models. Experiments demonstrating their effectiveness are conducted over distinct CNNs and datasets, focusing mainly on semantic segmentation (using U-Net, DeepLabv3+, SegNet, and VGG-16 as highly representative models). Pruned U-Net on agricultural benchmarks achieves 98.7% parameters and 97.5% FLOPs drop, with a 0.35% gain in accuracy. DeepLabv3+ and SegNet on CamVid reach 46.5% and 72.4% parameters reduction and a 51.9% and 83.6% FLOPs drop respectively, with almost no decrease in accuracy. VGG-16 on CIFAR-10 obtains up to 86.5% parameter and 82.2% FLOPs decrease with a 0.78% accuracy gain. • New filter pruning and fine-tuning strategies for segmentation and classification. • Novel layer pruning method for U-Net, a relevant semantic segmentation model. • Performing a detailed pruning survey on encoder–decoder and classification models. • Significant reduction in parameters and FLOPs maintaining networks efficiency. • Analyzing the dependence of the pruned models performance on the used dataset. [ABSTRACT FROM AUTHOR]

Subterranean estuaries are biogeochemically active coastal sites resulting from the underground mixing of fresh aquifer groundwater and seawater. In these systems, microbial activity can largely transform the chemical elements that may reach the sea through submarine groundwater discharge (SGD), but little is known about the microorganisms thriving in these land‐sea transition zones. We present the first spatially‐resolved characterization of the bacterial assemblages along a coastal aquifer in the NW Mediterranean, considering the entire subsurface salinity gradient. Combining bulk heterotrophic activity measurements, flow cytometry, microscopy and 16S rRNA gene sequencing we find large variations in prokaryotic abundances, cell size, activity and diversity at both the horizontal and vertical scales that reflect the pronounced physicochemical gradients. The parts of the transect most influenced by freshwater were characterized by smaller cells and lower prokaryotic abundances and heterotrophic production, but some activity hotspots were found at deep low‐oxygen saline groundwater sites enriched in nitrite and ammonium. Diverse, heterogeneous and highly endemic communities dominated by Proteobacteria, Patescibacteria, Desulfobacterota and Bacteroidota were observed throughout the aquifer, pointing to clearly differentiated prokaryotic niches across these transition zones and little microbial connectivity between groundwater and Mediterranean seawater habitats. Finally, experimental manipulations unveiled large increases in community heterotrophic activity driven by fast growth of some rare and site‐specific groundwater Proteobacteria. Our results indicate that prokaryotic communities within subterranean estuaries are highly heterogeneous in terms of biomass, activity and diversity, suggesting that their role in transforming nutrients will also vary spatially within these terrestrial–marine transition zones. [ABSTRACT FROM AUTHOR]

Pathogenic variants in the AP4B1 gene lead to a rare form of hereditary spastic paraplegia (HSP) known as SPG47. We report on a patient with a clinical suspicion of complicated HSP of the lower limbs with intellectual disability, as well as a novel homozygous noncanonical splice site variant in the AP4B1 gene, in which the effect on splicing was validated by RNA analysis. We sequenced 152 genes associated with HSP using Next‐Generation Sequencing (NGS). We isolated total RNA from peripheral blood and generated cDNA using reverse transcription‐polymerase chain reaction (RT‐PCR). A region of AP4B1 mRNA was amplified by PCR and the fragments obtained were purified from the agarose gel and sequenced. We found a homozygous variant of uncertain significance in the AP4B1 gene NM_006594.4: c.1511‐6C>G in the proband. Two different AP4B1 mRNA fragments were obtained in the patient and his carrier parents. The shorter fragment was the predominant fragment in the patient and revealed a deletion with skipping of the AP4B1 exon 10. The patient's longer fragment corresponded to an insertion of the last five nucleotides of AP4B1 intron 9. We confirmed that this variant affects the normal splicing of RNA, sustaining the molecular diagnosis of SPG47 in the patient. [ABSTRACT FROM AUTHOR]

The development of explainability methods for Convolutional Neural Networks (CNNs), under the growing framework of e x plainable Artificial Intelligence (xAI) for image understanding, is crucial due to neural networks success in contrast with their black box nature. However, usual methods focus on image visualizations and are inadequate to analyze the encoded contextual information (that captures the spatial dependencies of pixels considering their neighbors), as well as to explain the evolution of learning across layers without degrading the information. To address the latter, this paper presents a novel explanatory method based on the study of the latent representations of CNNs through their topology, and supported by Topological Data Analysis (TDA). For each activation layer after a convolution, the pixel values of the activation maps along the channels are considered latent space points. The persistent homology of this data is summarized via persistence landscapes, called Latent Landscapes. This provides a global view of how contextual information is being encoded, its variety and evolution, and allows for statistical analysis. The applicability and effectiveness of our approach is demonstrated by experiments conducted with CNNs trained on distinct datasets: (1) two U-Net segmentation models on RGB and pseudo-multiband images (generated by considering vegetation indices) from the agricultural benchmark CRBD were evaluated, in order to explain the difference in performance; and (2) a VGG-16 classification network on CIFAR-10 (RGB) was analyzed, showing how the information evolves within the network. Moreover, comparisons with state-of-the-art methods (Grad-CAM and occlusion) prove the consistency and validity of our proposal. It offers novel insights into the decision making process and helps to compare how models learn. • Design a novel topology-based explanatory method for Convolutional Neural Networks. • The topology of latent spaces is related to the variety of encoded information. • Discussing in detail the learning process and its relationship to performance. • Statistical analysis of the results obtained to further interpret the networks. [ABSTRACT FROM AUTHOR]

Despite the relevance of submarine groundwater discharge (SGD) for ocean biogeochemistry, the microbial dimension of SGD remains poorly understood. SGD can influence marine microbial communities through supplying chemical compounds and microorganisms, and in turn, microbes at the land–ocean transition zone determine the chemistry of the groundwater reaching the ocean. However, compared with inland groundwater, little is known about microbial communities in coastal aquifers. Here, we review the state of the art of the microbial dimension of SGD, with emphasis on prokaryotes, and identify current challenges and future directions. Main challenges include improving the diversity description of groundwater microbiota, characterized by ultrasmall, inactive and novel taxa, and by high ratios of sediment-attached versus free-living cells. Studies should explore microbial dynamics and their role in chemical cycles in coastal aquifers, the bidirectional dispersal of groundwater and seawater microorganisms, and marine bacterioplankton responses to SGD. This will require not only combining sequencing methods, visualization and linking taxonomy to activity but also considering the entire groundwater–marine continuum. Interactions between traditionally independent disciplines (e.g. hydrogeology, microbial ecology) are needed to frame the study of terrestrial and aquatic microorganisms beyond the limits of their presumed habitats, and to foster our understanding of SGD processes and their influence in coastal biogeochemical cycles. [ABSTRACT FROM AUTHOR]

This research aims to evaluate the scientific production on public relations addressing Latin America through a quantitative content and bibliometric analysis of articles and special issues published between 1980 and 2020, written in the official languages of the region: Spanish and Portuguese. The results of 123 articles confirm a substantial increase of studies since 2011, and some limitations of scientific dissemination. Although almost half of the authors were based in Brazil (40%), 17 base countries were counted. This work complements the latest studies on the object of study in English (Thelen, 2021) and provides the scientific community with recognition and access to native production. • A set of 123 native language articles where analised on public relations addressing Latin America. • There is a significant increase in the number of studies from 2016 onwards (29%). • Brazil accumulated the largest number of papers in the period (n = 49). • It was found that the impact in native languages (4.2) was lower than in English (43.2). [ABSTRACT FROM AUTHOR]

In parts of the Baltic Sea, the phytoplankton spring bloom communities, commonly dominated by diatoms, are shifting toward the co‐occurrence of diatoms and dinoflagellates. Although phytoplankton are known to shape the composition and function of associated bacterioplankton communities, the potential bacterial responses to such a decrease of diatoms are unknown. Here we explored the changes in bacterial communities and heterotrophic production during the spring bloom in four consecutive spring blooms across several sub‐basins of the Baltic Sea and related them to changes in environmental variables and in phytoplankton community structure. The taxonomic structure of bacterioplankton assemblages was partially explained by salinity and temperature but also linked to the phytoplankton community. Higher carbon biomass of the diatoms Achnanthes taeniata, Skeletonema marinoi, Thalassiosira levanderi, and Chaetoceros spp. was associated with more diverse bacterial communities dominated by copiotrophic bacteria (Flavobacteriia, Gammaproteobacteria, and Betaproteobacteria) and higher bacterial production. During dinoflagellate dominance, bacterial production was low and bacterial communities were dominated by Alphaproteobacteria, mainly SAR11. Our results suggest that increases in dinoflagellate abundance during the spring bloom will largely affect the structuring and functioning of the associated bacterial communities. This could decrease pelagic remineralization of organic matter and possibly affect the bacterial grazers communities. [ABSTRACT FROM AUTHOR]

Deep ocean microbial communities rely on the organic carbon produced in the sunlit ocean, yet it remains unknown whether surface processes determine the assembly and function of bathypelagic prokaryotes to a larger extent than deep‐sea physicochemical conditions. Here, we explored whether variations in surface phytoplankton assemblages across Atlantic, Pacific and Indian ocean stations can explain structural changes in bathypelagic (ca. 4,000 m) free‐living and particle‐attached prokaryotic communities (characterized through 16S rRNA gene sequencing), as well as changes in prokaryotic activity and dissolved organic matter (DOM) quality. We show that the spatial structuring of prokaryotic communities in the bathypelagic strongly followed variations in the abundances of surface dinoflagellates and ciliates, as well as gradients in surface primary productivity, but were less influenced by bathypelagic physicochemical conditions. Amino acid‐like DOM components in the bathypelagic reflected variations of those components in surface waters, and seemed to control bathypelagic prokaryotic activity. The imprint of surface conditions was more evident in bathypelagic than in shallower mesopelagic (200–1,000 m) communities, suggesting a direct connectivity through fast‐sinking particles that escape mesopelagic transformations. Finally, we identified a pool of endemic deep‐sea prokaryotic taxa (including potentially chemoautotrophic groups) that appear less connected to surface processes than those bathypelagic taxa with a widespread vertical distribution. Our results suggest that surface planktonic communities shape the spatial structure of the bathypelagic microbiome to a larger extent than the local physicochemical environment, likely through determining the nature of the sinking particles and the associated prokaryotes reaching bathypelagic waters. [ABSTRACT FROM AUTHOR]

Aerobic anoxygenic phototrophic (AAP) bacteria are a phylogenetically diverse and ubiquitous group of prokaryotes that use organic matter but can harvest light using bacteriochlorophyll a. Although the factors regulating AAP ecology have long been investigated through field surveys, the few available experimental studies have considered AAPs as a group, thus disregarding the potential differential responses between taxonomically distinct AAP assemblages. Here, we used sequencing of the pufM gene to describe the diversity of AAPs in 10 environmentally distinct temperate lakes, and to investigate the taxonomic responses of AAP communities in these lakes when subjected to similar experimental manipulations of light and predator removal. The studied communities were clearly dominated by Limnohabitans AAP but presented a clear taxonomic segregation between lakes presumably driven by local conditions, which was maintained after experimental manipulations. Predation reduction (but not light exposure) caused significant compositional shifts across most assemblages, but the magnitude of these changes could not be clearly related to changes in bulk AAP abundances or taxonomic richness of AAP assemblages during experiments. Only a few operational taxonomic units, which differed taxonomically between lakes, were found to respond positively during experimental treatments. Our results highlight that different freshwater AAP communities respond differently to similar control mechanisms, highlighting that in‐depth knowledge on AAP diversity is essential to understand the ecology and potential role of these photoheterotrophs. [ABSTRACT FROM AUTHOR]

Aerobic methanotrophic bacteria (methanotrophs) use methane as a source of carbon and energy, thereby mitigating net methane emissions from natural sources. Methanotrophs represent a widespread and phylogenetically complex guild, yet the biogeography of this functional group and the factors that explain the taxonomic structure of the methanotrophic assemblage are still poorly understood. Here, we used high‐throughput sequencing of the 16S rRNA gene of the bacterial community to study the methanotrophic community composition and the environmental factors that influence their distribution and relative abundance in a wide range of freshwater habitats, including lakes, streams and rivers across the boreal landscape. Within one region, soil and soil water samples were additionally taken from the surrounding watersheds in order to cover the full terrestrial–aquatic continuum. The composition of methanotrophic communities across the boreal landscape showed only a modest degree of regional differentiation but a strong structuring along the hydrologic continuum from soil to lake communities, regardless of regions. This pattern along the hydrologic continuum was mostly explained by a clear niche differentiation between type I and type II methanotrophs along environmental gradients in pH, and methane concentrations. Our results suggest very different roles of type I and type II methanotrophs within inland waters, the latter likely having a terrestrial source and reflecting passive transport and dilution along the aquatic networks, but this is an unresolved issue that requires further investigation. [ABSTRACT FROM AUTHOR]

Caffeine is a compound that can exert physiological–beneficial effects in the organism. Nevertheless, there are controversies about its protective-antioxidant and/or its negative genotoxic effect. To abound on the analysis of the possible genotoxic/antioxidant effect of caffeine, we used as research model the yeast Yarrowia lipolytica parental strain, and mutant strains (∆rad52 and ∆ku80), which are deficient in the DNA repair mechanisms. Caffeine (5 mM) showed a cytostatic effect on all strains, but after 72 h of incubation the parental and ∆ku80 strains were able to recover of this inhibitory effect on growth, whereas ∆rad52 was unable to recover. When cells were pre-incubated with caffeine and H2O2 or incubated with a mixture of both agents, a higher inhibitory effect on growth of mutant strains was observed and this effect was noticeably greater for the Δrad52 strain. The toxic effect of caffeine appears to be through a mechanism of DNA damage (genotoxic effect) that involves DSB generation since, in all tested conditions, the growth of Δrad52 strain (cells deficient in HR DNA repair mechanism) was more severely affected. [ABSTRACT FROM AUTHOR]

Microbial taxa range from being ubiquitous and abundant across space to extremely rare and endemic, depending on their ecophysiology and on different processes acting locally or regionally. However, little is known about how cosmopolitan or rare taxa combine to constitute communities and whether environmental variations promote changes in their relative abundances. Here we identified the Spatial Abundance Distribution (SpAD) of individual prokaryotic taxa (16S rDNA‐defined Operational Taxonomic Units, OTUs) across 108 globally‐distributed surface ocean stations. We grouped taxa based on their SpAD shape ("normal‐like"‐ abundant and ubiquitous; "logistic"‐ globally rare, present in few sites; and "bimodal"‐ abundant only in certain oceanic regions), and investigated how the abundance of these three categories relates to environmental gradients. Most surface assemblages were numerically dominated by a few cosmopolitan "normal‐like" OTUs, yet there was a gradual shift towards assemblages dominated by "logistic" taxa in specific areas with productivity and temperature differing the most from the average conditions in the sampled stations. When we performed the SpAD categorization including additional habitats (deeper layers and particles of varying sizes), the SpAD of many OTUs changed towards fewer "normal‐like" shapes, and OTUs categorized as globally rare in the surface ocean became abundant. This suggests that understanding the mechanisms behind microbial rarity and dominance requires expanding the context of study beyond local communities and single habitats. We show that marine bacterial communities comprise taxa displaying a continuum of SpADs, and that variations in their abundances can be linked to habitat transitions or barriers that delimit the distribution of community members. [ABSTRACT FROM AUTHOR]

This article presents reflections about the hegemonic ideological representations contained in the discourse of the Movement for Life and the Family in Paraguay. This includes a hermeneutic analysis of the discourse of videos that were part of the Facebook campaign "We are many, many more" produced by the Movement. The interpretation of the data has been made from the perspective of feminist gender studies and from the Paraguayan debate about the diversity of configurations and family structures and their role in educational content. The analysis of the social and political context and the debate around the subsequent elections indicate that the main objective of the campaign was promoting a specific profile of political candidate, according to the values of the conservative electorate. [ABSTRACT FROM AUTHOR]

Bioelectronic tongues (bioET) made of sensors combining enzymes and nanomaterials have been shown to be advantageous due to the specificity offered by the biosensors and the enhanced sensitivity provided by the nanomaterials. In this work, an innovative bioET for milk analysis is developed using potentiometric biosensors based on lactic dehydrogenase, galactose oxidase and urease specific for the detection of compounds of interest in milk (lactic acid, galactose and urea). The performance of the biosensors has been fostered by covalently immobilizing the enzymes on membranes of carboxylated polyvinyl chloride combined with gold nanoparticles. The design and composition of the biosensors contributes to preserving the enzymatic activity, allowing limits of detection in the range of 10−5 – 10−6 M with excellent sensitivity and reproducibility (variation coefficients ranged from 1 to 5.1%). The three biosensors, combined in a single device and coupled to a pattern recognition software, can discriminate efficiently twelve classes of milk with different fat content (skimmed, semi-skimmed and whole milk) and nutritional characteristics (calcium enriched, lactose free and folic acid-enriched). The bioET shows an excellent classification capability with an accuracy of up to 99.7%. By applying Support Vector Machine (SVM) analysis, the BioET can perform the simultaneous assessment of eight physicochemical parameters (acidity, fat, proteins, lactose, density, urea, dry matter and nonfat dry matter) with satisfactory correlation coefficients and low residual errors. The results are further improved by implementing ensemble methodologies. The proposed strategy has been demonstrated to be useful for improving the performance of bioETs in the dairy industry. • A potentiometric bioET specifically dedicated to milk analysis was developed. • Enzymes were covalently linked to membranes combining Carboxilated-PVC and AuNPs. • The effective enzymatic immobilization helped to retain the enzymatic activity. • Using SVM and ensemble methods, nine physicochemical parameters can be determined simultaneously. [ABSTRACT FROM AUTHOR]

Freshwater bacterioplankton communities are influenced by the transport of bacteria from the surrounding terrestrial environments. It has been shown that, although most of these dispersed bacteria gradually disappear along the hydrologic continuum, some can thrive in aquatic systems and become dominant, leading to a gradual succession of communities. Here we aimed at exploring the environmental factors driving the structure of such contrasting bacterial populations as well as their functional properties. Using Illumina sequencing of the 16S rRNA gene, we characterized the taxonomic composition of bacterioplankton communities from 10 streams and rivers in Québec spanning the whole hydrologic continuum (river Strahler order 0 to 7), which were sampled in two occasions. With the aim to understand the fate and controls of the transported bacteria, among the taxa present at the origin of the hydrologic gradient (i.e., in the smallest headwater streams) we identified two types of dynamics: i) 'Tourist' taxa, which were those that decreased in abundance from the headwaters towards the largest rivers, and ii) 'Seed' taxa, those that increased their abundances along the hydrologic continuum. Communities changed gradually from the fast-flowing headwater streams dominated by 'Tourist' taxa (ca. 95% of the sequences) towards the largest rivers (Strahler order 4-7) where 'Seed' taxa comprised up to 80% of community sequences. Variation in taxonomic composition of the communities dominated by 'Tourist' taxa in streams seemed related to different degree of terrestrial inputs, whereas compositional changes in 'Seed' communities in the large rivers were linked to differences in autochthonous processes. Finally, the two types of communities differed significantly in their metabolic potential assessed through Biolog Ecoplates. All this suggests that hydrologic transport modulates the gradual replacement of two contrasting population types subjected to different environmental controls and with different metabolic potentials. Moreover, we show that the separate exploration of the two pools of taxa allows unveiling environmental drivers and processes operating on them that remain hidden if explored at the whole community level. [ABSTRACT FROM AUTHOR]

Aquatic bacterial communities harbour thousands of coexisting taxa. To meet the challenge of discriminating between a 'core' and a sporadically occurring 'random' component of these communities, we explored the spatial abundance distribution of individual bacterioplankton taxa across 198 boreal lakes and their associated fluvial networks (188 rivers). We found that all taxa could be grouped into four distinct categories based on model statistical distributions (normal like, bimodal, logistic and lognormal). The distribution patterns across lakes and their associated river networks showed that lake communities are composed of a core of taxa whose distribution appears to be linked to in-lake environmental sorting (normal-like and bimodal categories), and a large fraction of mostly rare bacteria (94% of all taxa) whose presence appears to be largely random and linked to downstream transport in aquatic networks (logistic and lognormal categories). These rare taxa are thus likely to reflect species sorting at upstream locations, providing a perspective of the conditions prevailing in entire aquatic networks rather than only in lakes. [ABSTRACT FROM AUTHOR]

This article accounts for the way proportionality principles have been executed in Colombia for the control of constitutionality of the states of emergency, through the evaluation of six (6) special cases from 1991, four (4) of them related to internal states of exception and two (2) of them related to social emergency. A qualitative methodology was used to describe the way the Constitutional Court was applying the proportionality principle to analyze such exceptions, accounting for an analysis matrix that describes the key points of such principle, to wit: a) the existence of a special crisis and not of a structural damage to the states of exception; b) not suspension of human rights or basic freedom of people over which measures are imposed; c) not interruption of the normal operation of the government branches; d) the exercise of powers exclusively to effectively face abnormalities; the strict relationship between cause and abnormality and, in this sense, the direction of decrees only and exclusively to resolve the causes that give origin to the state of exception; e) the length defined for the states of exception (Cifuentes, 2002) to conclude that the Constitutional Court, while applying the proportionality principle, has failed to make an exhaustive judgment of the requirements incorporated; in this way, it has allowed a perpetuation of the executive power and a government with no separation of powers. [ABSTRACT FROM AUTHOR]

Aim The need to go beyond taxonomy to understand patterns in microbial function has led to an increased use of trait-based approaches, yet we know little about how microbial functional traits vary across large-scale environmental gradients in natural ecosystems. Here, we apply a trait-based approach to explore the large-scale variability in the trait structure underlying the processing of dissolved organic matter (DOM) by boreal bacterioplankton communities, as well as its regulation and links to taxonomic composition. Location Samples were collected from 296 rivers and lakes across five regions in northern Quebec (Canada), which span large gradients in environmental, climatic and geographical properties typical of the boreal zone. Methods We used the metabolic profiles obtained with Biolog EcoPlates® as an imprint of the trait structure underlying bacterial processing of DOM, and Illumina sequencing of the 16SrRNA gene to characterize the taxonomic composition of these bacterial assemblages. The resulting spatial patterns were compared with an array of climatic, landscape and limnological properties varying at the landscape scale. Results Despite a clear regional segregation of the sampled sites based on environmental variables, the trait structure of boreal bacteria did not show any regional or ecosystem-specific patterns, but rather was linked to a gradient of quality of DOM. Community trait configurations diverged progressively with decreasing terrestrial influence, probably due to local processes that transform and diversify the available pool of DOM. This DOM quality gradient did not explain the taxonomic biogeography of these communities, which was controlled by a different set of environmental factors. Main conclusions The functional biogeography of boreal bacterioplankton is driven by the nature of the DOM pool, and particularly by the influence of terrestrial DOM. The lack of coherence between functional and taxonomic biogeographies implies that the environmental controls of freshwater bacterial performance cannot be directly inferred from spatial patterns in taxonomic composition. [ABSTRACT FROM AUTHOR]

Bacteria inhabiting boreal freshwaters are part of metacommunities where local assemblages are often linked by the flow of water in the landscape, yet the resulting spatial structure and the boundaries of the network metacommunity have never been explored. Here, we reconstruct the spatial structure of the bacterial metacommunity in a complex boreal aquatic network by determining the taxonomic composition of bacterial communities along the entire terrestrial/aquatic continuum, including soil and soilwaters, headwater streams, large rivers and lakes. We show that the network metacommunity has a directional spatial structure driven by a common terrestrial origin of aquatic communities, which are numerically dominated by taxa recruited from soils. Local community assembly is driven by variations along the hydrological continuum in the balance between mass effects and species sorting of terrestrial taxa, and seems further influenced by priority effects related to the spatial sequence of entry of soil bacteria into the network. [ABSTRACT FROM AUTHOR]

Large rivers are commonly regulated by damming, yet the effects of such disruption on prokaryotic communities have seldom been studied. We describe the effects of the three large reservoirs of the Ebro River ( NE Iberian Peninsula) on bacterioplankton assemblages by comparing several sites located before and after the impoundments on three occasions. We monitored the abundances of several bacterial phylotypes identified by r RNA gene probing, and those of two functional groups (picocyanobacteria and aerobic anoxygenic phototrophic bacteria- AAPs). Much greater numbers of particles colonized by bacteria were found in upstream waters than downstream sites. Picocyanobacteria were found in negligible numbers at most sites, whereas AAPs constituted up to 14% of total prokaryotes, but there was no clear effect of reservoirs on the spatial dynamics of these two groups. Instead, damming caused a pronounced decline in Betaproteobacteria, Gammaproteobacteria and Bacteroidetes from upstream to downstream sites, whereas Alphaproteobacteria and Actinobacteria significantly increased after the reservoirs. Redundancy analysis revealed that conductivity, temperature and dissolved inorganic nitrogen were the environmental predictors that best explained the observed variability in bacterial community composition. Our data show that impoundments exerted significant impacts on bacterial riverine assemblages and call attention to the unforeseen ecological consequences of river regulation. [ABSTRACT FROM AUTHOR]

We investigated the short-term effects of variable solar irradiance and spectrum on the gross biological production of dimethylsulfide (DMS), a trace gas with potential climatic effects, in eight experiments performed at different times of the year in a northwest Mediterranean coastal site. Experimentally determined net community DMS production, DMS photolysis, and dark microbial DMS consumption rates were used to calculate gross community DMS production by budgeting. In addition, the composition of the bacterioplankton and phytoplankton communities in the initial samples, and the photoinhibition of bulk bacterial heterotrophic activity and phytoplankton photosynthetic efficiency were monitored. Our results show that: (1) gross DMS production is irradiance dependent, with a maximum short-term stimulation factor of 2- to 6-fold compared to dark incubations; (2) its spectral shape is variable but generally similar to that of phytoplankton photoinhibition or photodamage, with more effective stimulation at shorter ultraviolet wavelengths; and (3) stronger stimulation occurs when samples are overexposed with respect to their prior exposure. Remarkably, the photoresponse of gross DMS production was in most cases strong enough to (at least) compensate the photochemical DMS loss at the water subsurface. Such response would prevent DMS depletion in stratified and highly irradiated waters. Since the initial microbial communities were representative of meso- to oligotrophic conditions, our observations should apply to a wide variety of oceanic regimes. [ABSTRACT FROM AUTHOR]

The influence of solar ultraviolet radiation and photosynthetically active radiation (PAR) on summertime marine bacterial uptake and assimilation of sulfur from radiolabeled dimethlysulfoniopropionate (S-DMSP) was studied at four Arctic and two Antarctic stations. Incubations with H-leucine were also conducted for comparative purposes as a measurement of bacterial activity. Arctic waters were characterized by large numbers of colonial Phaeocystis pouchetii and higher DMSP concentrations than in the two diatom-dominated Antarctic samples. Exposure to full sunlight radiation (280-700 nm), and to a lesser extent to PAR + UVA (320-700 nm), generally decreased the bacterial assimilation of H-leucine with respect to darkness, and caused variable effects on S-DMSP assimilation. By using a single-cell approach involving microautoradiography we found high percentages of sulfur assimilating cells within the bacterial groups Gammaproteobacteria, Bacteroidetes, SAR11 and Roseobacter despite the varying DMSP concentrations between Arctic and Antarctic samples. The dominant SAR11 clade contributed 50-70% of the cells assimilating both substrates in the Arctic stations, whereas either Gammaproteobacteria or SAR11 were the largest contributors to H-leucine uptake in samples from the two Antarctic stations. Only one station was analyzed for single-cell S-DMSP assimilation in Antarctica, and Gammaproteobacteria were major contributors to its uptake, providing the first evidence for Antarctic bacteria actively taking up S-DMSP. PAR + UVA repeatedly increased the number of SAR11 cells assimilating H-leucine. This pattern also occurred with other S-DMSP assimilating groups, though not so consistently. Our results support a widespread capability of polar bacteria to assimilate DMSP-sulfur during the season of maximum DMSP concentrations, and show for the first time that all major polar taxa can be highly active at this assimilation under the appropriate circumstances. Our findings further confirm the role of sunlight as a modulator of heterotrophic carbon and sulfur fluxes in the surface ocean. [ABSTRACT FROM AUTHOR]

Even though the uptake and assimilation of organic compounds by phytoplankton has been long recognized, very little is still known about its potential ecological role in natural marine communities and whether it varies depending on the light regimes the algae experience. We combined measurements of size-fractionated assimilation of trace additions of ³H-leucine and 35S-dimethylsulfoniopropionate (DMSP) with microautoradiography to assess the extent and relevance of osmoheterotrophy in summer phytoplankton assemblages from Arctic and Antarctic waters, and the role of solar radiation on it was further investigated by exposing samples to different radiation spectra. Significant assimilation of both substrates occurred in the size fraction containing most phytoplankton (.5 mm), sunlight exposure generally increasing 35S-DMSP- sulfur assimilation and decreasing ³H-leucine assimilation. Microautoradiography revealed that the capacity to take up both organic substrates seemed widespread among different polar algal phyla, particularly in pennate and centric diatoms, and photosynthetic dinoflagellates. Image analysis of the microautoradiograms showed for the first time interspecific variability in the uptakes of 35S-DMSP and ³H-leucine by phytoplankton depending on the solar spectrum. Overall, these results suggest that the role of polar phytoplankton in the utilization of labile dissolved organic matter may be significant under certain conditions and further confirm the relevance of solar radiation in regulating heterotrophy in the pelagic ocean. [ABSTRACT FROM AUTHOR]

The effect of photosynthetically available radiation (PAR; 400-700 nm) and ultraviolet radiation (UVR; 280-400 nm) on marine bacterial heterotrophic activity was assessed monthly throughout a seasonal cycle in Blanes Bay (northwestern Mediterranean Sea). Seawater samples amended with ³H-leucine were exposed to solar radiation under three radiation treatments: PAR +UVR (280-700 nm), PAR +UVA (320-700 nm), and PAR only. Parallel reference incubations in the dark and under a fixed artificial light source (PAR only) were also performed. Exposure to high UVR doses caused strong inhibition of ³H-leucine incorporation rates (LIR), whereas natural PAR doses did not cause overall significant effects. Within UVR, UVA radiation accounted for most of the reduction in LIR, and this effect was modulated by the proportionality of the experimental light to the previous light exposure history of the samples. Constant (artificial) PAR-only exposure led to a general but seasonally variable increase in bacterial heterotrophic production compared to the dark controls, with large increases in spring and lower changes during summer. This pattern was likely caused by the stimulation of the bacterial group Gammaproteobacteria, which showed higher numbers of cells active in ³Hleucine uptake after light exposure. Again, the previous light history of the samples seemed to partly explain the measured effects. Overall, our results show variable responses of bacterial activities to light manipulations, depending on seasonally changing light conditions and communities, and stress the importance of realistic simulation of light exposure conditions for ecosystem-relevant photobiological studies with microbial plankton. [ABSTRACT FROM AUTHOR]

The sensitivity of coastal marine bacterioplankton to natural photosynthetically active radiation ( PAR, 400-700 nm) and ultraviolet radiation ( UVR, 280-400 nm) was evaluated in five experiments over a seasonal cycle in the Blanes Bay, NW Mediterranean Sea. Exposure to natural solar radiation generally inhibited bulk bacterial activities or damaged membrane integrity when irradiances were high (i.e. spring and summer experiments) and, in general, UVB (280-320 nm) accounted for most of the inhibition. When assessing activity (3H-leucine uptake) at the single-cell level by microautoradiography and rRNA gene probing, seasonally varying responses and sensitivities were found among bacterial groups. While autumn and winter irradiances seemed too low to cause changes in activity, variable effects were found in spring and summer. SAR11 was consistently inhibited by UVR and PAR exposure, whereas G ammaproteobacteria and B acteroidetes showed higher resistance. R oseobacter, S ynechococcus and the NOR5 clade were occasionally photostimulated in their activity, mainly because of PAR. Our results indicate that a component of seasonality exists in the bacterial responses to solar radiation, which vary not only depending on the irradiance and the spectral characteristics, but also on the previous light history and the taxonomic composition of the community. [ABSTRACT FROM AUTHOR]

There is a large body of evidence supporting a major role of heterotrophic bacteria in dimethylsulphoniopropionate (DMSP) utilisation as a source of reduced sulphur. However, a role for phototrophic microorganisms has been only recently described and little is known about their contribution to DMSP consumption and the potential modulating effects of sunlight. In an attempt to ascertain the relative quantitative roles of heterotrophic bacteria and picophytoplankton in the osmoheterotrophic uptake of DMSP-sulphur upon exposure to natural sunlight conditions, we incubated northwestern Mediterranean waters under various optical filters and used an array of bulk and single-cell activity methods to trace the fate of added 35S-DMSP. Flow cytometry cell sorting confirmed dark 35S uptake by Prochlorococcus, Synechococcus and heterotrophic bacteria, the latter being the most efficient in terms of uptake on a cell volume basis. Under exposure to full sunlight, however, the relative contribution of Synechococcus was significantly enhanced, mainly because of the inhibition of heterotrophic bacteria. Microautoradiography showed a strong increase in the proportion of Synechococcus cells actively taking up 35S-DMSP, which, after full sunlight exposure, made up to 15% of total active Bacteria. Parallel incubations with 3H-leucine generally showed no clear responses to light. Finally, size-fractionated assimilation experiments showed greater relative cyanobacterial assimilation during the day than at night compared with that of heterotrophic bacteria. Our results show for the first time a major influence of sunlight in regulating the competition among autotrophic and heterotrophic picoplankton for DMSP uptake at both the daily and seasonal time scales. [ABSTRACT FROM AUTHOR]

The characterization of wild species of the genus Nicotiana is very important for the genetic breeding programs of Nicotiana tabacum L. because they can be a source of pest resistance genes to increase the genetic variability in the only commercial species of this genus in Cuba. The objective of this work was to characterize the genetic variability in ten species of the Nicotiana genus of the germoplasm bank in Cuba through the analysis of nine isozyme systems and total proteins. The isozymes assayed were peroxidase, polyphenol oxidase, esterase, carbonic anhidrase, superoxide dismutase, diaphorase, acid phosphatase, alkaline phosphatase and malic enzyme, as well as total proteins. Isozyme electrophoresis was performed on vertical slab polyacrylamide gels (PAGE). The total polymorphism level among species in the systems studied was 92,7%, where the most polymorphic systems were peroxidase, acid phosphatase and malic enzyme with 100%. These polymorphic systems, jointly with alkaline phosphatase and total protein, were the most important markers for the identification and characterization of Nicotiana species since they allowed distinguishing band patterns for each of them. This result is a first approach to the isozyme studies in wild species from the germoplasm bank in Cuba, leading to the knowledge of the variability level of those species. [ABSTRACT FROM AUTHOR]

Abstract: RNA viruses replicate their genomes with a very high error rate and constitute highly heterogeneous mutant distributions similar to the molecular quasispecies introduced to explain the evolution of prebiotic replicators. The genetic information included in a quasispecies can only be faithfully transmitted below a critical error rate. When the error threshold is crossed, the population structure disorganizes, and it is substituted by a randomly distributed mutant spectrum. For viral quasispecies, the increase in error rate is associated with a decrease in specific infectivity that can lead to the extinction of the population. In contrast, a strong resistance to extinction has been observed in populations subjected to bottleneck events despite the increased accumulation of mutations. In the present study, we show that the mutagenic nucleoside analogue 5-azacytidine (AZC) is a potent mutagen for bacteriophage Qβ. We have evaluated the effect of the increase in the replication error rate in populations of the bacteriophage Qβ evolving either in liquid medium or during development of clonal populations in semisolid agar. Populations evolving in liquid medium in the presence of AZC were extinguished, while during plaque development in the presence of AZC, the virus experienced a significant increase in the replicative ability. Individual viruses isolated from preextinction populations could withstand high error rates during a number of plaque-to-plaque transfers. The response to mutagenesis is interpreted in the light of features of plaque development versus infections by free-moving virus particles and the distance to a mutation–selection equilibrium. The results suggest that clonal bacteriophage populations away from equilibrium derive replicative benefits from increased mutation rates. This is relevant to the application of lethal mutagenesis in vivo, in the case of viruses that encounter changing environments and are transmitted from cell to cell under conditions of limited diffusion that mimic the events taking place during plaque development. [Copyright &y& Elsevier]

The production of biomass and antibacterial extracellular products by Lactobacillus casei subsp, casei CECT 4043 was followed in both batch and in realkalized fed-batch cultures. Enhanced concentrations of biomass and antibacterial extracellular products were obtained with the use of the latter fermentation technique in comparison with the batch mode. The culture obtained by fed-batch fermentation was mixed with skim milk and used to prepare a probiotic feed for weaned piglets. To test the effect of the potentially probiotic culture of L. casei on body weight gain, feed intake, feed conversion efficiency, and on fecal coliform counts of piglets, two groups of animals received either feed supplemented with the probiotic preparation or avilamycin for 28 days. The control group was fed nonsupplemented feed. At the end of the administration period (day 28), the groups receiving probiotic and avilamycin exhibited the highest average body weight gain values, although the mean feed intake and feed conversion efficiency values were not different among the groups (P > 0.05). For the entire experimental period (42 days), the control group exhibited the lowest feed intake value, the probiotic group exhibited the highest feed conversion efficiency value, and the antibiotic group exhibited the highest body weight gain (P < 0.05). Interestingly, no significant difference in body weight gain was observed between the probiotic and the control groups by day 42 (P > 0.05). Fecal coliform values decreased (although not significantly) by day 28 in the three groups. However, the mean counts returned to pretreatment levels by day 42 in all groups. [ABSTRACT FROM AUTHOR]

Abstract: Human immunodeficiency virus type 1 (HIV-1) strains having dipeptide insertions in the fingers subdomain and other drug resistance-related mutations scattered throughout their reverse transcriptase (RT)-coding region show high-level resistance to zidovudine (AZT) and other nucleoside analogues. Those phenotypic effects have been correlated with their increased ATP-dependent phosphorolytic activity on chain-terminated primers. Mutations T69S and T215Y and a dipeptide insertion (i.e. Ser-Ser) between positions 69 and 70 are required to achieve low-level resistance to thymidine analogues. However, additional amino acid substitutions are necessary to achieve the high-level phenotypic resistance to AZT shown by clinical HIV isolates carrying a dipeptide insertion in their RT-coding region. In order to identify those mutations that contribute to resistance in the sequence context of an insertion-containing RT derived from an HIV clinical isolate (designated as SS RT), we expressed and purified a series of chimeric enzymes containing portions of the wild-type or SS RT sequences. ATP-mediated excision activity measurements using AZT- and stavudine (d4T)-terminated primers and phenotypic assays showed that molecular determinants of high-level resistance to AZT were located in the fingers subdomain of the polymerase. Further studies, using recombinant RTs obtained by site-directed mutagenesis, revealed that M41L, A62V and in a lesser extent K70R, were the key mutations that together with T69S, T215Y and the dipeptide insertion conferred high levels of ATP-dependent phosphorolytic activity on AZT and d4T-terminated primers. Excision activity correlated well with AZT susceptibility measurements, and was consistent with phenotypic resistance to d4T. Structural analysis of the location of the implicated amino acid substitutions revealed a coordinated effect of M41L and A62V on the positioning of the β3–β4 hairpin loop, which plays a key role in the resistance mechanism. [Copyright &y& Elsevier]

Given the alarming world's pollution due the irrational use of chemicals products and the universal preoccupation because of this, a lot of research has been dedicated to use non polluting organic products for the control of different plagues and illness. Our work is based in the use of homeopathic products for the phytopathogens fungi control in vitro. Our research was accomplished in the Plants Protection Laboratory of Villa Clara Province during april, 2004. We used six homeopathic products and four phytopathogens fungi stems Fusarium solani, Rizoctonia solani, Phytophthora parasitica and Altenaria brasicae. We used the poisoned medium technique and punction sowing to evaluate the colony's diametrical growing at 24, 48 and 72 hours. There were no total control of fungi but a consistent diminution of mycelia growing of the stems treated. [ABSTRACT FROM AUTHOR]

Given the alarming world's pollution due the irrational use of chemicals products and the universal preoccupation because of this, a lot of research has been dedicated to use non polluting organic products for the control of different plagues and illness. Our work is based in the use of homeopathic products for the phytopathogenic fungi control in vitro. Our research was accomplished in the Plants Protection Laboratory of Villa Clara Province during April, 2004. We used six homeopathic products and four phytopathogens fungi stems Fusarium solani, Rizoctonia solani, Phytophthora parasitica and Altenaria brasicae. We used the poisoned medium technique and function sowing to evaluate the colony's diametrical growing at 24, 48 and 72 hours. There were no total control of fungi but a consistent diminution of mycelia growing of the stems treated. [ABSTRACT FROM AUTHOR]

A genetic screen based on the blue-white β-galactosidase complementation assay designed to detect G→A mutations arising during RNA-dependent DNA synthesis was used to compare the fidelity of mutant human immunodeficiency virus type 1 reverse transcriptases (RTs) with the mutations M230L and M230I with the wild-type enzyme, in the presence of biased deoxynucleoside triphosphate (dNTP) pools. The mutant RTs with the M230L and M230I changes were found to be 20 to 70 times less faithful than the wild-type RT in the presence of low [dCTP]/[dTTP] ratios but showed similar fidelity in assays carried out with equimolar concentrations of each nucleotide. Biased dNTP pools led to short tandem repeat deletions in the target sequence, which were also detectable with the assay. However, deletion frequencies were similar for all of the RTs tested. The reported data suggest that RT pausing due to the low dNTP levels available in the RT reaction mixture facilitates strand transfer, in a process that is not necessarily mediated by nucleotide misinsertion. [ABSTRACT FROM AUTHOR]

Although some methods for measuring bioadhesion/mucoadhesion have been proposed, a standardized method is not yet available. This is expected to hinder systematic comparisons of results across studies. This study aimed to design a single/systematic in vitro method for measuring bioadhesion/mucoadhesion that is applicable to various pharmaceutical dosage forms. To this end, we measured the peak force and work of adhesion of minitablets, pellets, and a bioadhesive emulsion using a texture analyzer. Porcine tissue was used to simulate human stomach/skin conditions. The results of these formulations were then compared to those for formulations without the bioadhesive product. We conducted a case study to assess the stability of a bioadhesive emulsion. The results for the two parameters assessed were contact time = 60 s and contact force = 0.5 N at a detachment speed of 0.1 mm/s. Significant differences were observed between the bioadhesive and control formulations, thus demonstrating the adhesive capacity of the bioadhesive formulations. In this way, a systematic method for assessing the bioadhesive capacity of pharmaceutical dosage forms was developed. The method proposed here may enable comparisons of results across studies, i.e., results obtained using the same and different pharmaceutical formulations (in terms of their bioadhesion/mucoadhesion capacity). This method may also facilitate the selection of potentially suitable formulations and adhesive products (in terms of bioadhesive properties). [ABSTRACT FROM AUTHOR]

X-linked myotubular myopathy (XLMTM; OMIM 310400) is a centronuclear congenital muscular disorder of X-linked recessive inheritance. Although female carriers are typically asymptomatic, affected heterozygous females have been described. Here, we describe the case of a sporadic female patient with suspicion of centronuclear myopathy and a heterozygous large deletion at Xq28 encompassing the MAMLD1 , MTM1 , MTMR1 , CD99L2 , and HMGB3 genes. The deletion was first detected using a custom next generation sequencing (NGS)-based multigene panel and finally characterized by comparative genomic hybridization array and multiplex ligation probe assay techniques. In this patient we have confirmed, by MTM1 mRNA quantification, a MTM1 gene expression less than the expected 50 percent in patient muscle. The significant 20% reduction in MTM1 mRNA expression in muscle, precludes low level of the normal myotubularin protein as the cause of the phenotype in this heterozygous female. We have also found that BIN1 expression in patient muscle biopsy was significantly increased, and postulate that BIN1 expression will be increased in XLMTM patient muscle as an attempt to maintain muscle function. • Manifestations in recessive X-linked diseases carriers has been linked to a skewed inactivation of the X chromosome. • We reported a female patient with XLMTM and a MTM1 gene expression less than 50 percent in patient muscle. • The genetic diagnosis of female patients with XLMTM should be aided by XCI analysis, histological studies, and RNA analysis. • BIN1 expression, increased in patient muscle, will be increased in XLMTM patient as an attempt to maintain muscle function. [ABSTRACT FROM AUTHOR]

We studied leucine turnover using a primed infusion of [1-14C]- l-leucine and glucose turnover using a primed infusion of [6-3H]- d-glucose in five alcoholic patients without liver damage and five age-matched controls. Infusions were maintained for 6 hr, and at the end of the 3rd hour, a 0.8 g/kg iv ethanol load was administered in 20 min. Leucine flux, nonoxidative disposal and oxidation rates, and glucose rate of appearance were calculated during the 3rd and 6th hours of infusion. Ethanol disappearance rate and the percentage completely metabolized to CO2 and H2O in 3 hr were also calculated. Compared with controls, alcoholics had significantly higher basal leucine flux (55.6 ± 12 vs. 37.3 ± 9.3 μ m/m2/min) and nonoxidative disposal (48.7 ± 8.7 vs. 31.1 ± 7.5 μ m/m2/min). No differences were observed in basal glucose appearance rates in alcoholics and controls (397.6 ± 115.2 vs. 349.4 ± 120.6 μ m/m2/min). Compared with controls, alcoholics had a higher alcohol disappearance rate (2.72 ± 0.59 vs. 1.84 ± 0.43 m m/kg/min) and percentage of ethanol metabolized to CO2 and H2O in 3 hr (40.6 ± 10.2 vs. 22.9 ± 6.9%). After the ethanol load, both leucine turnover and glucose rate of appearance decreased significantly only in alcoholics. There was a positive correlation between the change in leucine flux and ethanol disappearance rate and percentage metabolized to CO2 and H2O in alcoholics. [ABSTRACT FROM AUTHOR]

Summary: The aerobic anoxygenic phototrophic (AAP) bacteria are common in most marine environments but their global diversity and biogeography remain poorly characterized. Here, we analyzed AAP communities across 113 globally‐distributed surface ocean stations sampled during the Malaspina Expedition in the tropical and subtropical ocean. By means of amplicon sequencing of the pufM gene, a genetic marker for this functional group, we show that AAP communities along the surface ocean were mainly composed of members of the Halieaceae (Gammaproteobacteria), which were adapted to a large range of environmental conditions, and of different clades of the Alphaproteobacteria, which seemed to dominate under particular circumstances, such as in the oligotrophic gyres. AAP taxa were spatially structured within each of the studied oceans, with communities from adjacent stations sharing more taxonomic similarities. AAP communities were composed of a large pool of rare members and several habitat specialists. When compared to the surface ocean prokaryotic and picoeukaryotic communities, it appears that AAP communities display an idiosyncratic global biogeographical pattern, dominated by selection processes and less influenced by dispersal limitation. Our study contributes to the understanding of how AAP communities are distributed in the horizontal dimension and the mechanisms underlying their distribution across the global surface ocean. [ABSTRACT FROM AUTHOR]

Methane-oxidizing bacteria (MOB) present in the water column mitigate methane (CH 4) emissions from hydropower complexes to the atmosphere. By creating a discontinuity in rivers, dams cause large environmental variations, including in CH 4 and oxygen concentrations, between upstream, reservoir, and downstream segments. Although highest freshwater methanotrophic activity is often detected at low oxygen concentrations, CH 4 oxidation in well-oxygenated downstream rivers below dams has also been reported. Here we combined DNA and RNA high-throughput sequencing with microscopic enumeration (by CARD-FISH) and biogeochemical data to investigate the abundance, composition, and potential activity of MOB taxa from upstream to downstream waters in the tropical hydropower complex Batang Ai (Malaysia). High relative abundance of MOB (up to 61% in 16S rRNA sequences and 19% in cell counts) and enrichment of stable isotopic signatures of CH 4 (up to 0‰) were detected in the hypoxic hypolimnion of the reservoir and in the outflowing downstream river. MOB community shifts along the river-reservoir system reflected environmental sorting of taxa and an interrupted hydrologic connectivity in which downstream MOB communities resembled reservoir's hypolimnetic communities but differed from upstream and surface reservoir communities. In downstream waters, CH 4 oxidation was accompanied by fast cell growth of particular MOB taxa. Our results suggest that rapid shifts in active MOB communities allow the mitigation of CH 4 emissions from different zones of hydropower complexes, including in quickly re-oxygenated rivers downstream of dams. Unlabelled Image • Methane-oxidizing bacteria (MOB) can reach high abundances in reservoirs. • Inflowing MOB communities are restructured along a hydropower complex. • Methane dynamics can be accompanied by rapid shifts in MOB communities. [ABSTRACT FROM AUTHOR]

Active non-muscle myosin II (NMII) enables migratory cell polarization and controls dynamic cellular processes, such as focal adhesion formation and turnover and cell division. Filament assembly and force generation depend on NMII activation through the phosphorylation of Ser19 of the regulatory light chain (RLC). Here, we identify amino acid Tyr (Y) 155 of the RLC as a novel regulatory site that spatially controls NMII function. We show that Y155 is phosphorylated in vitro by the Tyr kinase domain of epidermal growth factor (EGF) receptor. In cells, phosphorylation of Y155, or its phospho-mimetic mutation (Glu), prevents the interaction of RLC with the myosin heavy chain (MHCII) to form functional NMII units. Conversely, Y155 mutation to a structurally similar but non-phosphorylatable amino acid (Phe) restores the more dynamic cellular functions of NMII, such as myosin filament formation and nascent adhesion assembly, but not those requiring stable actomyosin bundles, e.g., focal adhesion elongation or migratory front-back polarization. In live cells, phospho-Y155 RLC is prominently featured in protrusions, where it prevents NMII assembly. Our data indicate that Y155 phosphorylation constitutes a novel regulatory mechanism that contributes to the compartmentalization of NMII assembly and function in live cells. • Myosin light chain (RLC) is phosphorylated in tyrosine • Aberrant cell function by RLC deletion is not corrected by phospho-mimetic RLC • Phosphorylation of RLC in Y155 impairs formation of functional myosin hexamers • Phospho-Y155 RLC mainly appears at lamellipodia Aguilar-Cuenca et al. determine the cellular function of myosin light chain (RLC) phosphorylation on tyrosine. Phospho-Tyr155 RLC mainly appears at lamellipodia, preventing the interaction of the regulatory light chain with myosin heavy chain II, impairing formation of functional myosin hexamers and limiting myosin assembly during protrusion. [ABSTRACT FROM AUTHOR]

The MYH9 gene encodes the heavy chain (MHCII) of non-muscle myosin II A (NMII-A). This is an actin-binding molecular motor essential for development that participates in many crucial cellular processes such as adhesion, cell migration, cytokinesis and polarization, maintenance of cell shape and signal transduction. Several types of mutations in the MYH9 gene cause an array of autosomal dominant disorders, globally known as MYH9-related diseases (MYH9-RD). These include May-Hegglin anomaly (MHA), Epstein syndrome (EPS), Fechtner syndrome (FTS) and Sebastian platelet syndrome (SPS). Although caused by different MYH9 mutations, all patients present macrothrombocytopenia, but may later display other pathologies, including loss of hearing, renal failure and presenile cataracts. The correlation between the molecular and cellular effects of the different mutations and clinical presentation are beginning to be established. In this review, we correlate the defects that MYH9 mutations cause at a molecular and cellular level (for example, deficient filament formation, altered ATPase activity or actin-binding) with the clinical presentation of the syndromes in human patients. We address why these syndromes are tissue restricted, and the existence of possible compensatory mechanisms, including residual activity of mutant NMII-A and/or the formation of heteropolymers or co-polymers with other NMII isoforms. [ABSTRACT FROM AUTHOR]

Due the actual world situation about the irrational abuse of chemicals, a lot of research has been dedicated to use non polluting organic products to control different plagues and illness. Our work is based in the use of homeopathic products in order to control phytopathogens fungi associated to seeds. Our work was made in the Plants Protection Laboratory of Villa Clara Province during april in 2004. We used 6 homeopathics products in two kinds of seeds, (french beans and indian carob beans). These seeds were treated with the different homeopathic products during 20 minutes and then mounted in plates by the wet chamber method recommended by the International Seed Testing Association (ISTA) with three replics for each treatment and a witness for each kind of seed. We obtained different degrees of control with the homeopathic products in both kinds of seeds of the phytopathogenic fungi found like Fusarium sp., Cladosporium sp., Macrophomina phaseolina and other associated species of Aspergillus sp., Rhyzopus sp., and Penicillium sp. [ABSTRACT FROM AUTHOR]

Due the current world situation about the irrational abuse of chemicals, a lot of research has been dedicated to use non polluting organic products to control different plagues and illness. Our work is based in the use of homeopathic products in order to control phytopathogenic fungi associated to seeds. Our work was made in the Plants Protection Laboratory of Villa Clara Province during april in 2004. We used 6 homeopathics products in two kinds of seeds, (french beans and indian carob beans). These seeds were treated with the different homeopathic products during 20 minutes and then mounted in plates by the wet chamber method recommended by the International Seed Testing Association (ISTA) with three replicas for each treatment and a witness for each kind of seed. We obtained different degrees of control with the homeopathic products in both kinds of seeds of the phytopathogenic fungi found like Fusarium sp., Cladosporium sp., Macrophomina phaseolina and other associated species of Aspergillus sp., Rhyzopus sp., and Penicillium sp. [ABSTRACT FROM AUTHOR]

The article presents case study of a 16‑year‑old male patient with a myopathy with proximal muscle weakness and was diagnosed with calpainopathy. It mentions that electromyography showed myopathic pattern, muscle biopsy and a dystrophic pattern; and a lower intensity of staining with anti‑DYS‑3 antibody shown by immunohistochemical analysis. It also reflects on mutation identification a necessary approach to an upcoming gene therapy.

Summary: Lake methane (CH4) emissions are largely controlled by aerobic methane‐oxidizing bacteria (MOB) which mostly belong to the classes Alpha‐ and Gammaproteobacteria (Alpha‐ and Gamma‐MOB). Despite the known metabolic and ecological differences between the two MOB groups, their main environmental drivers and their relative contribution to CH4 oxidation rates across lakes remain unknown. Here, we quantified the two MOB groups through CARD‐FISH along the water column of six temperate lakes and during incubations in which we measured ambient CH4 oxidation rates. We found a clear niche separation of Alpha‐ and Gamma‐MOB across lake water columns, which is mostly driven by oxygen concentration. Gamma‐MOB appears to dominate methanotrophy throughout the water column, but Alpha‐MOB may also be an important player particularly in well‐oxygenated bottom waters. The inclusion of Gamma‐MOB cell abundance improved environmental models of CH4 oxidation rate, explaining part of the variation that could not be explained by environmental factors alone. Altogether, our results show that MOB composition is linked to CH4 oxidation rates in lakes and that information on the MOB community can help predict CH4 oxidation rates and thus emissions from lakes. [ABSTRACT FROM AUTHOR]

Supracondylar are the most common fractures in the elbow joint during childhood with a peak between the ages five to seven. Besides, they are the second most common type of fracture in the pediatric population in general. The typical cause of the injury is the patient falling from their own height on the palm of the hand with the elbow in hyperextension. The diagnosis is based on the clinical suspicion according to the injury mechanism and the age of the patient, in addition to a standard elbow X-ray from two views. The Gartland classification is the most used instrument to establish the severity of the fracture and to guide the treatment, which can be orthopedic in non-displaced fracture, whereas the method of choice for correction of displaced fractures is closed reduction and percutaneous fixation. The most common complication is the neuropraxia of the median nerve. Others are the brachial artery injury, compartment syndrome, Volkamm ischemic contracture, sliding of the pins and ulna varus. [ABSTRACT FROM AUTHOR]

Streams are typically supersaturated in carbon dioxide (CO 2 ) and methane (CH 4 ), and are recognized as important components of regional carbon (C) emissions in northern landscapes. Whereas there is consensus that in most of the systems the CO 2 emitted by streams represents C fixed in the terrestrial ecosystem, the pathways delivering this C to streams are still not well understood. We assessed the contribution of direct soil CO 2 injection versus the oxidation of soil-derived dissolved organic C (DOC) and CH 4 in supporting CO 2 supersaturation in boreal streams in Québec. We measured the concentrations of CO 2 , CH 4 and DOC in 43 streams and adjacent soil waters during summer base-flow period. A mass balance approach revealed that all three pathways are significant, and that the mineralization of soil-derived DOC and CH 4 accounted for most of the estimated stream CO 2 emissions (average 75% and 10%, respectively), and that these estimated contributions did not change significantly between the studied low order (≤ 3) streams. Whereas some of these transformations take place in the channel proper, our results suggest that they mainly occur in the hyporheic zones of the streams. Our results further show that stream CH 4 emissions can be fully explained by soil CH 4 inputs. This study confirms that these boreal streams, and in particular their hyporheic zones, are extremely active processors of soil derived DOC and CH 4 , not just vents for soil produced CO 2 . [ABSTRACT FROM AUTHOR]

Two diel cycle studies were conducted to determine the effect of day-night light changes on winter bacterial activity in the coastal Mediterranean (Blanes Bay Microbial Observatory). Bacterial abundances, bacterial heterotrophic activity, and flagellate grazing counts were determined at 4-h intervals during two 3-d periods separated by 2 d. Twice a day, the single-cell activity of major bacterial groups was further analyzed by applying microautoradiography combined with catalyzed reporter deposition-fluorescence in situ hybridization. During the first cycle, all the measured parameters (including the number of active cells in most groups) varied synchronously, with higher values at night and lower during the day. An episode of strong winds between the two studied periods disrupted this periodicity at the onset of the second cycle. The bulk incorporation of ³H-leucine recovered the diel pattern after 2 d, mostly driven by the activity of Gammaproteobacteria. Among the possibilities considered, the observed nighttime increases in the grazing activity of heterotrophic nanoflagellates appeared to partially drive the activity of all bacterial taxa through potential periodic release of dissolved organic matter. [ABSTRACT FROM AUTHOR]