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Abstract Background Long-chain acyl-coenzyme A synthetase (LACS) is a type of acylating enzyme with AMP-binding, playing an important role in the growth, development, and stress response processes of plants. Results The research team identified different numbers of LACS in four cotton species (Gossypium hirsutum, Gossypium barbadense, Gossypium raimondii, and Gossypium arboreum). By analyzing the structure and evolutionary characteristics of the LACS, the GhLACS were divided into six subgroups, and a chromosome distribution map of the family members was drawn, providing a basis for further research classification and positioning. Promoter cis-acting element analysis showed that most GhLACS contain plant hormones (GA, MeJA) or non-biological stress-related cis-elements. The expression patterns of GhLACS under salt stress treatment were analyzed, and the results showed that GhLACS may significantly participate in salt stress response through different mechanisms. The research team selected 12 GhLACSs responsive to salt stress for tissue expression analysis and found that these genes are expressed in different tissues. Conclusions There is a certain diversity of LACS among different cotton species. Analysis of promoter cis-acting elements suggests that GhLACS may be involved in regulating plant growth, development and stress response processes. GhLACS25 was selected for in-depth study, which confirmed its significant role in salt stress response through virus-induced gene silencing (VIGS) and induced expression in yeast cells.

Sesame, one of the ancient oil crops, is an important oilseed due to its nutritionally rich seeds with high protein content. Genomic scale information for sesame has become available in the public databases in recent years. The genes and their families involved in oil biosynthesis in sesame are less studied than in other oilseed crops. Therefore, we retrieved a total of 69 genes and their translated amino acid sequences, associated with gene families linked to the oil biosynthetic pathway. Genome-wide in silico mining helped identify key regulatory genes for oil biosynthesis, though the findings require functional validation. Comparing sequences of the SiSAD (stearoyl-acyl carrier protein (ACP)-desaturase) coding genes with known SADs helped identify two SiSAD family members that may be palmitoyl-ACP-specific. Based on homology with lysophosphatidic acid acyltransferase (LPAAT) sequences, an uncharacterized gene has been identified as SiLPAAT1. Identified key regulatory genes associated with high oil content were also validated using publicly available transcriptome datasets of genotypes contrasting for oil content at different developmental stages. Our study provides evidence that a longer duration of active oil biosynthesis is crucial for high oil accumulation during seed development. This underscores the importance of early onset of oil biosynthesis in developing seeds. Up-regulating, identified key regulatory genes of oil biosynthesis during early onset of seed development, should help increase oil yields. [ABSTRACT FROM AUTHOR]

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Background Left atrial (LA) strain parameters have been demonstrated to be valuable predictors of atrial fibrillation (AF) in several patient cohorts. The purpose of this study was to investigate whether LA strain, assessed by two-dimensional speckle-tracking echocardiography, can be used to predict the development of AF in the general population. Methods and results This prospective longitudinal study included 4466 participants from the fifth Copenhagen City Heart Study. All participants underwent a health examination, including echocardiographic measurements of LA strain. Participants with prevalent AF at baseline were excluded. The primary endpoint was incident AF. During a median follow-up period of 5.3 years, 154 (4.3%) participants developed AF. In univariable analysis, peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and LA strain during the conduit phase were significantly associated with the development of AF. PALS [hazard ratio (HR) 1.05, 95% confidence interval (CI) (1.03–1.07), P  < 0.001, per 1% decrease] and PACS (HR 1.08, 95% CI (1.05–1.12), P  < 0.001, per 1% decrease] remained independent predictors of AF in multivariable analysis. In addition, PALS and PACS remained significantly associated with AF development even in participants with normal-sized atria and normal left ventricular (LV) systolic function. Conclusion In the general population, PALS and PACS independently predict incident AF. These findings remained consistent even in participants with normal-sized LA and normal LV systolic function. [ABSTRACT FROM AUTHOR]

Copyright of VertigO is the property of La Revue Electronique en Sciences de l'Environnement VertigO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In plants, Long-chain acyl-CoA synthetases (LACSs) play key roles in activating fatty acids to fatty acyl-CoA thioesters, which are then further involved in lipid synthesis and fatty acid catabolism. LACSs have been intensively studied in Arabidopsis , but its evolutionary relationship in green plants is unexplored. In this study, we performed a comprehensive genome-wide analysis of the LACS gene family across green plants followed by phylogenetic clustering analysis, gene structure determination, detection of conserved motifs, gene expression in tissues and subcellular localization. Our results identified LACS genes in 122 plant species including algae, low land plants (i.e., mosses and lycophytes), monocots, and eudicots. In total, 697 sequences were identified, and 629 sequences were selected because of alignment and some duplication errors. The retrieved amino acid sequences ranged from 271 to 1056 residues and diversified in intron/exon patterns in different LACSs. Phylogenetic clustering grouped LACS gene family into six major clades with distinct potential functions. This classification is well supported by examining gene structure and conserved motifs. Also, gene expression analysis and subcellular localization substantiate with clade division in the phylogeny, indicating that the evolutionary pattern is visible in their functionality. Additionally, experimental analysis of lacs2 mutant validated that LACS2 plays key roles in suberin synthesis. Thus, our study not only provides an evolutionary mechanism underlying functional diversification but also lays the foundation for further elucidation of the LACS gene family. • This is the first genome-wide identification of 629 LACSs genes in 122 plant species. • Phylogenetic analysis of LACSs genes shows six major clades with potential distinct functions. • LACSs genes present specific expression patterns across different tissues with different level. [ABSTRACT FROM AUTHOR]

Purpose: To compare surgical parameters among eyes undergoing laser-assisted cataract surgery (LACS) using different lens fragmentation patterns (LFP). Methods: Prospective, randomized, unmasked clinical trial. One-hundred eyes underwent LACS and were randomly assigned to 1 of 3 LFP treatment groups: (1) laser capsulotomy only; no lens fragmentation (NLF) (n = 34); (2) three-plane chop (TPC) (n = 33); and, (3) pie-cut pattern (PCP) fragmentation (n = 33). Prechop phacoemulsification (PHACO) was performed on all eyes using the same femtosecond (FS) laser and active-fluidics PHACO machine. Main outcome measures: FS laser dock time (s), PHACO time (s), PHACO power (%), cumulative dissipated energy (CDE) (%-s), irrigating fluid volume, and operative time. Results: The 3 treatment groups were comparable in terms of patient age (P = 0.164) and nuclear density (P = 0.669). FS dock time was higher in the PCP group (184.18 ± 25.86) compared to the TPC (145.09 ± 14.15) group (P < 0.001). PHACO time was significantly shorter in the PCP (23.19 ± 17.20 s) compared to TPC (35.27 ± 17.70) and NLF (46.15 ± 23.72) groups (P < 0.001). PHACO power was lower in the PCP (11.81 ± 3.71) compared to the NLF (14.41 ± 1.88) and TPC (14.04 ± 2.46) groups (P < 0.001). CDE was lower in the PCP (2.85 ± 2.32) compared to NLF (6.55 ± 3.32) and TPC (6.55 ± 5.45) groups (P < 0.001). Fluid volumes and operative times were similar. Conclusion: LFP can influence PHACO surgical parameters. Extensive fragmentation patterns such as PCP appear to lower PHACO time, power, and CDE and may potentially reduce the risk of PHACO related complications. [ABSTRACT FROM AUTHOR]

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Copyright of Knowledge & Management of Aquatic Ecosystems is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Palaeoenvironmentalists from the Chrono-environment laboratory in Besançon have been working in Greenland since 2006. The Study area is located in southern Greenland, within the Norse Eastern settlement occupied from 986 to 1450 cal. BC. The study aims at characterizing the impact of this first colonization on a pristine environment. The lacustrine sequence was studied with the help of different proxies (palynology, Non Pollen Palynomorph, Diatoms, sedimentology, geochemical and isotope analyses) and, in some site, the Norse settlement was integrated in the Holocene context. About 20 sediment cores were collected during 5 fieldtrips from 2006 to 2013. The Holocene sequence from Igaliku, the medieval Garðar, starts at 8000 cal. AD and the record of pollen rain start at about 6100 cal. AD ; it is one of the best radiocarbon dated sequence of this area. From 6100 to 2500 cal. AD, pollen diagram from Lake Igaliku shows that vegetation is dominated by juniper and willow. Starting in 2500 cal. AD, with the beginning of the neoglacial period, Juniper pollen decreases while dwarf birch and white birch become the dominant tree taxa. Decrease in birch and juniper and the rise in coprophilous fungi are the first evidences of the Norse settlement. The presence of settlers and livestock is clearly recorded: increasing soil erosion frequencies Norse apophytes (sheep sorrel, dandelion, buttercup) and coprophilous fungi. This colonization phase is followed by a period of decreasing human impact at the beginning of the 14th century, with a decrease in coprophilous fungi suggesting a reduced grazing pressure. The regrowth of willow and birch and the disappearance of anthropogenic indicators except sheep sorrel type between the 15th and 18th century demonstrate the abandonment of the settlement, until the development of contemporary agriculture in the 20th century. Impact of modern agriculture on vegetation is comparable to the Norse impact. However, mechanization and fertilization have heavily increased soil erosion and transformed the lake ecosystem.

Gene editing tools (Zinc-Finger Nucleases, ZFN; Transcription Activator-Like Effector Nucleases, TALEN; and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated (Cas)9, CRISPR-Cas9) provide us with a powerful means of performing genetic engineering procedures. A combinational approach that utilizes both somatic cell nuclear transfer (SCNT) and somatic cell gene editing facilitates the generation of genetically engineered animals. However, the associated research has utilized markers and/or selected genes, which constitute a potential threat to biosafety. Microhomologous-mediated end-joining (MMEJ) has showed the utilization of micro-homologous arms (5–25 bp) can mediate exogenous gene insertion. Dairy milk is a major source of nutrition worldwide. However, most people are not capable of optimally utilizing the nutrition in milk because of lactose intolerance. Sulfolobus solfataricus β-glycosidase (LacS) is a lactase derived from the extreme thermophilic archaeon Sulfolobus solfataricus . Our finally aim was to site-specific integrated LacS gene into cow's genome through TALEN-mediated MMEJ and produce low-lactose cow. Firstly, we constructed TALENs vectors which target to the cow's β-casein locus and LacS gene expression vector which contain TALEN reorganization sequence and micro-homologous arms. Then we co-transfected these vectors into fetal derived skin fibroblasts and cultured as monoclone. Positive cell clones were screened using 3′ junction PCR amplification and sequencing analysis. The positive cells were used as donors for SCNT and embryo transfer (ET). Lastly, we detected the genotype through PCR of blood genomic DNA. This resulted in a LacS knock-in rate of 0.8% in TALEN-treated cattle fetal fibroblasts. The blastocyst rate of SCNT embryo was 27%. The 3 months pregnancy rate was 20%. Finally, we obtained 1 newborn cow (5%) and verified its genotype. We obtained 1 site-specific marker-free LacS transgenic cow. It provides a basis to solve lactose intolerance by gene engineering breeding. This study also provides us with a new strategy to facilitate gene knock-ins in livestock using techniques that exhibit improved biosafety and intuitive methodologies. [ABSTRACT FROM AUTHOR]

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Long-chain acyl-Coenzyme A (CoA) synthetases (LACSs) catalyze the formation of long-chain acyl-CoA, and play important roles in fatty acid metabolism including phospholipids, triacylglycerol (TAG) biosynthesis and fatty acid β-oxidation. Here, we report the characterization of a LACS gene from Brassica napus. It is highly homologous to Arabidopsis LACS4 and thus designated as BnLACS4. The cloned gene BnLACS4 could complement a LACS-deficient yeast strain YB525. It is mainly expressed in flowers and developing seeds where lipid biosynthesis is at high rate in Brassica napus. When transiently expressed in tobacco leaves, BnLACS4 is localized in endoplasmic reticulum (ER), the common site for eukaryotic pathway of lipid biosynthesis. Expression of BnLACS4 in the yeast strain pep4 increased its lipid content. Taken together, our results suggest that BnLACS4 may be involved in lipid biosynthesis in B. napus.

In recent decades, marked declines in calcium (Ca) concentrations have been noted in many softwater boreal lakes, and are believed to be a long-term consequence of acid deposition as well as other stressors (such as timber harvesting). Reduced Ca availability may act as a potent environmental stressor. Investigations of the direct ecological impacts of lower Ca concentrations in freshwater systems have largely focused on Ca-rich members of the Cladocera; however, a growing body of work, spanning several scientific fields, suggests Ca decline will have profound direct and indirect consequences for aquatic ecosystems. Here, we synthesize recent laboratory analyses and field surveys to provide an overview of these consequences, while highlighting paleolimnological investigations that provide some long-term perspective on the phenomenon. However, considerable questions remain regarding 'baseline' or pre-impact conditions, due to the accelerated leaching of Ca from watershed soils during the period of anthropogenic influence. Furthermore, catchment-specific differences in both leaching rates and the initial size of the Ca pool in watershed soils complicate determination of the eventual endpoints of the declines. Despite these uncertainties, persistent low Ca concentrations are anticipated to impede biological recovery from lake acidification, and that ongoing declines will have cascading effects throughout aquatic ecosystems due to the loss of vulnerable taxa. To better understand how reduced Ca availability will continue to change affected surface waters and how these changes will interact with other environmental stressors will require continued investigation of the declines from multiple scientific perspectives. [ABSTRACT FROM AUTHOR]

Transcatheter aortic valve implantation (TAVI) is maturing strongly as an alternative to surgical aortic valve replacement (SAVR) in patients who are inoperable/high risk for open heart surgery. General anesthesia (GA) is the usual mode of anesthesia in these patients, but local anesthesia with conscious sedation (LACS) has recently been described as a safe alternative with some added advantages. We report 2 cases who were unfit for GA and were done successfully under LACS.

The Joseph-Samson Dam is located on the St. Charles River near the confluence with the St. Lawrence River in the Lower Town of Quebec City. The dam creates a 3.7 km long reservoir, with a very popular linear park running alongside. This water body has esthetic value and allows recreational boating. With its anti-tidal gates, the dam protects from flooding during very high spring tides in the St. Lawrence. However, the dam has completely changed the formerly natural estuary into a channel with sedimentation formed from the organic and inorganic sediment influx coming from the semi-urban, urban and forest watershed. Highly productive fish runs up the St. Charles are a thing of the past and significant reduction in dissolved oxygen is now often observed. Furthermore, the dam may actually increase the risk of flooding in the Lower Town under high flows. One-dimensional simulations (HEC-RAS) were performed to assess the dam's impact on flood risks for different bottom gate settings and two-dimensional simulations (RIVER 2D) were performed to assess the dam's impact on river velocities and sedimentation processes. [ABSTRACT FROM AUTHOR]

Converging evidence suggests that freshwater systems play an important role in the carbon cycles at both regional and global scales. In addition, there are serious concerns that ongoing and future changes to the environment could alter these dynamics. This is particularly important in the boreal forest biome, which contains a very high density of lakes. In this review, we synthesize the current state of research to provide a critical overview of ( i) the role of boreal lakes as emitters versus sinks of carbon, ( ii) their contribution to the regional carbon balance, ( iii) knowledge gaps that may inhibit an accurate evaluation of the role of boreal lakes in a landscape context, and ( iv) impacts of environmental perturbations on carbon dynamics in boreal lakes. Several recent studies indicate that boreal lakes are actively processing, emitting, and storing carbon rather than being passive transport conduits. Yet, generalizing the role of lake ecosystems for the overall carbon balance of the boreal forest biome is challenging because of the scarcity of studies on lake carbon budgets in a landscape context that can capture the potential temporal and spatial variability and uncertainties associated with the available estimates of carbon pools and fluxes. Further, environmental perturbations, such as climate change, acidic deposition, and nutrient enrichment, likely affect both carbon export to lakes and in-lake carbon processing in boreal regions. Predicting their overall impacts on lake carbon budgets is particularly difficult, not only because individual environmental stressors likely affect multiple processes involved in carbon cycling, but also because often multiple stressors act synergistically or antagonistically at the landscape level. Accordingly, long-term, system-wide approaches are required to accurately evaluate the importance of lakes for boreal carbon budgets in a changing environment. [ABSTRACT FROM AUTHOR]

Dans le cadre du Programme de Surveillance répondant à la Directive européenne Cadre sur l'Eau, un suivi du phytoplancton des plans d'eau de plus de 50 hectares est réalisé dans le bassin Rhin-Meuse. C'est lors de ce suivi que la diatomée centrique Aulacoseira scalaris (Grunow in Van Heurck) Houk, Klee & Passauer a été identifiée dans les lacs de Longemer en 2010 (Xonrupt-Longemer, France) et de Gérardmer en 2011 (Gérardmer, France). Sa présence a été à nouveau détectée dans les échantillons prélevés en 2014 sur ces deux lacs. Aulacoseira scalaris n'avait été jusqu'à présent trouvée que dans des échantillons fossiles à subfossiles des U.S.A. (État de l'Oregon, et Virginia City de l'État du Nevada) et de France (Lac de Gérardmer, Vosges, France). Cette espèce ayant été retrouvée vivante dans le phytoplancton de ces deux lacs des Vosges, elle ne doit plus être considérée comme uniquement une diatomée fossile. Des informations sur son autécologie sont proposées grâce aux données physicochimiques des deux lacs, et sa morphologie est comparée avec les espèces d' Aulacoseira semblables présentes dans la littérature. As a part of the Monitoring Program of the European Water Framework Directive, the phytoplankton of water bodies over 50 hectares have been studied in the Rhine-Meuse river basin. During the analysis, the centric diatom Aulacoseira scalaris (Grunow in Van Heurck) Houk, Klee & Passauer was identified from Longemer Lake in 2010 (Xonrupt-Longemer, France) and Gérardmer Lake in 2011 (Gérardmer, France). The presence of this diatom was again confirmed in samples collected in 2014 from both lakes. Interestingly, Aulacoseira scalaris until recently has been found only in fossil to subfossil materials from U.S.A. (State of Oregon and Virginia City, State of Nevada) and France (Vosges Mountains, Gérardmer Lake). The species has been observed for the first time in live material and should no longer be considered as strictly fossil or subfossil. Information on its autecology is provided using the physicochemical data of the lakes, and its morphology is compared with similar species of Aulacoseira in available literature. [ABSTRACT FROM AUTHOR]

The article discusses the contribution of an operon consisted of LacS symporter, integral membrane protein, and β-galactosidase to bifidobacterial galactooligosaccharides (GOS), a prebiotics, consumption. Topics discussed include analysis of GOS consumption by 14 bifidobacterial strains; transcription analysis of GOS consumer; and the growth of bifidobacteria on GOS.

The present study aimed to compare the results of hand-assisted laparoscopic surgery (HALS) and conventional laparotomy (CL) at a single institution in Japan. Of the 212 patients with stage I/II/III colorectal cancer who received a curative resection, 98 patients underwent HALS and 114 patients underwent CL. The clinical background and post-operative management did not differ between the two groups. There were no significant differences in the 3-year relapse-free and 3-year overall survival rates between the HALS and CL groups for the patients in any stage. Blood loss during surgery was 250.1 and 135.5 ml (mean and median; the same hereafter) in stage I patients receiving HALS versus 608.2 and 315.5 ml in stage I CL patients (P=0.006), while it was 277.6 and 146 ml in stage II patients receiving HALS versus 548.6 and 347 ml in stage II CL patients (P=0.004). Post-operative hospital stay was recorded at 16.8 and 15 days in stage III patients receiving HALS versus 23.1 and 21 days in stage III CL patients (P=0.001). There were no significant differences in the operating time or complications between the two groups. These results indicate that the survival rate was comparable for HALS and CL, while HALS caused less surgical stress and achieved a better cosmetic outcome. The results of the final analysis of this cohort are awaited. [ABSTRACT FROM AUTHOR]

A large dam is planned at Stiegler’s Gorge in Tanzania. The change in the Rufiji River flood pattern will affect downstream ecosystems. This paper concentrates on the highly productive floodplain lakes that play a vital role in local livelihoods. A participatory monitoring system with village-based observers collected water level, rainfall, fisheries and food data from 2001 to 2011. Water balances of the lakes show dependence on the Rufiji River flood, with varying vulnerability. With the dam design flood of 2500 m3 s-1, lakes with a high threshold and small catchment will dry out quickly. Lakes with a lower threshold and substantial catchment are more robust but may still dry out during prolonged local drought. Analysis of rainfall (1923–2012) indicates a recent decrease. The data were analysed through feedback workshops with local observers, government technical staff and researchers. Through this collaborative approach, local capacity in preparing for the post-dam future was enhanced.Editor D. Koutsoyiannis; Guest editor M. AcremanCitation Duvail, S., Mwakalinga, A.B., Eijkelenburg, A., Hamerlynck, O., Kindinda, K., and Majule, A., 2014. Jointly thinking the post-dam future: exchange of local and scientific knowledge on the lakes of the Lower Rufiji, Tanzania. Hydrological Sciences Journal, 59 (3–4), 713–730. [ABSTRACT FROM PUBLISHER]

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Abstract: Fungi and animals constitute sister kingdoms in the eukaryotic domain of life. The major classes of transporters, channels, sensors, and effectors that move and respond to calcium ions were already highly networked in the common ancestor of fungi and animals. Since that time, some key components of the network have been moved, altered, relocalized, lost, or duplicated in the fungal and animal lineages and at the same time some of the regulatory circuitry has been dramatically rewired. Today the calcium transport and signaling networks in fungi provide a fresh perspective on the scene that has emerged from studies of the network in animal cells. This review provides an overview of calcium signaling networks in fungi, particularly the model yeast Saccharomyces cerevisiae, with special attention to the dominant roles of acidic calcium stores in fungal cell physiology. [Copyright &y& Elsevier]

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Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As the outermost layer on aerial tissues of the primary plant body, the cuticle plays important roles in plant development and physiology. The major components of the cuticle are cutin and cuticular wax, both of which are composed primarily of fatty acid derivatives synthesized in the epidermal cells. Long-chain acyl-CoA synthetases (LACS) catalyze the formation of long-chain acyl-CoAs and the Arabidopsis genome contains a family of nine genes shown to encode LACS enzymes. LACS2 is required for cutin biosynthesis, as revealed by previous investigations on lacs2 mutants. Here, we characterize lacs1 mutants of Arabidopsis that reveals a role for LACS1 in biosynthesis of cuticular wax components. lacs1 lacs2 double-mutant plants displayed pleiotropic phenotypes including organ fusion, abnormal flower development and reduced seed set; phenotypes not found in either of the parental mutants. The leaf cuticular permeability of lacs1 lacs2 was higher than that of either lacs1 or lacs2 single mutants, as determined by measurements of chlorophyll leaching from leaves immersed in 80% ethanol, staining with toluidine blue dye and direct measurements of water loss. Furthermore, lacs1 lacs2 mutant plants are highly susceptible to drought stress. Our results indicate that a deficiency in cuticular wax synthesis and a deficiency in cutin synthesis together have compounding effects on the functional integrity of the cuticular barrier, compromising the ability of the cuticle to restrict water movement, protect against drought stress and prevent organ fusion. [ABSTRACT FROM AUTHOR]