15 research outputs found

    The contribution of sex chromosome conflict to disrupted spermatogenesis in hybrid house mice

    Get PDF
    Incompatibilities on the sex chromosomes are important in the evolution of hybrid male sterility, but the evolutionary forces underlying this phenomenon are unclear. House mice (Mus musculus) lineages have provided powerful models for understanding the genetic basis of hybrid male sterility. X chromosome-autosome interactions cause strong incompatibilities in Mus musculus F1 hybrids, but variation in sterility phenotypes suggests a more complex genetic basis. Additionally, X-Y chromosome conflict has resulted in rapid expansions of ampliconic genes with dosage-dependent expression that is essential to spermatogenesis. Here we evaluated the contribution of X-Y lineage mismatch to male fertility and stage-specific gene expression in hybrid mice. We performed backcrosses between two house mouse subspecies to generate reciprocal Y-introgression strains and used these strains to test the effects of X-Y mismatch in hybrids. Our transcriptome analyses of sorted spermatid cells revealed widespread overexpression of the X chromosome in sterile F1 hybrids independent of Y chromosome subspecies origin. Thus, postmeiotic overexpression of the X chromosome in sterile F1 mouse hybrids is likely a downstream consequence of disrupted meiotic X-inactivation rather than X-Y gene copy number imbalance. Y-chromosome introgression did result in subfertility phenotypes and disrupted expression of several autosomal genes in mice with an otherwise non-hybrid genomic background, suggesting that Y-linked incompatibilities contribute to reproductive barriers, but likely not as a direct consequence of X-Y conflict. Collectively, these findings suggest that rapid sex chromosome gene family evolution driven by genomic conflict has not resulted in strong male reproductive barriers between these subspecies of house mice

    Galaktoglukomannany (GGM) wyodr臋bnione z trocin drewna 艣wierkowego do zastosowa艅 medycznych

    No full text
    The article presents a method of extracting galactoglucomannas (GGMs) from softwood (spruce). GGMs were extracted using thermal and enzymatic treatment in an aqueous environment. The GGMs extracted, depending on the extraction method, were characterized by different compositions of simple carbohydrates i. e. glucose, galactose and mannose, as well as by the average molecular weight. Evaluation of the composition of GGMs obtained was performed using GC/MS and SEC. The biopolymer composites obtained by combining GGMs with microcrystalline chitosan (MCCh), showed suitability for constructing dressing materials in the form of sponges. The studies were performed in order to evaluate antibacterial properities of composite realtive to Escherichia coli standard Gram (-) and their susceptibility to enzymatic and hydrolytic degradation. The research confirmed the usefulness of MCCh/GGMs composities for constructing dressing materials.W artykule przedstawiono metod臋 wyodr臋bniania galaktoglukomannan贸w (GGM) ze 艣wierkowych trocin drzewnych, z zastosowaniem obr贸bki termicznej i enzymatycznej prowadzonej w 艣rodowisku wodnym. Wyodr臋bnione GGM (w zale偶no艣ci od metody wyodr臋bniania) charakteryzowa艂y si臋 zr贸偶nicowanym sk艂adem pod wzgl臋dem zawarto艣ci poszczeg贸lnych cukr贸w prostych tj. glukozy, galaktozy i mannozy oraz warto艣ci膮 艣redniej masy cz膮steczkowej. Ocen臋 sk艂adu i zmian strukturalnych otrzymanych GGM prowadzono z wykorzystaniem chromatografii GC/MS, SEC. Wytworzone biopolimerowe kompozyty, uzyskane w wyniku po艂膮czenia GGM z mikrokrystalicznym chitozanem (MKCh), wykaza艂y przydatno艣膰 do konstrukcji materia艂贸w opatrunkowych w postaci g膮bki. Oceniono dzia艂anie przeciwbakteryjne wytworzonych biokompozyt贸w wobec wzorcowej bakterii Escherichia coli Gram (-) oraz ich podatno艣膰 na degradacj臋 hydrolityczn膮 i enzymatyczn膮. Przeprowadzone badania potwierdzi艂y przydatno艣膰 GGM do wytwarzania kompozyt贸w z MKCh, stanowi膮cych podstawowy sk艂adnik konstrukcyjny materia艂贸w opatrunkowych

    Badania nad wyodr臋bnianiem w艂贸kien celulozowych z jednorocznych odpadowych surowc贸w ro艣linnych

    No full text
    This paper presents the results of cellulose fibre extraction from plant biomass including: rape, hemp and flax straws. The selected materials were treated by thermal/mechanical/chemical method in order to remove non-cellulosic components such as lignin, hemicellulose, and pectin as well as to obtain cellulosic material with suitable structure and properties necessary for the manufacture of nanofibres. It has been shown that the use of multistage chemical treatment using oxygen and peroxide compounds as delignifing agents for hemp and flax straws, allowed the safe removal of lignin and other non-cellulosic components without degradation of the cellulose fibres obtained, while maintaining a polymerization degree above 1000 units. It was found out that it is possible to obtain cellulose fibres from hemp and flax straws (type retted flax straw-fibre variety, flax straw-oil variety), which can be processed into cellulose micro-and nanofibres.W artykule przedstawiono wyniki bada艅 procesu wyodr臋bniania celulozowych sk艂adnik贸w w艂贸knistych z r贸偶nych biomasowych surowc贸w ro艣linnych mi臋dzy innymi: s艂omy rzepaku, s艂omy konopnej, a tak偶e s艂om lnianych. Badane surowce ro艣linne charakteryzowa艂y si臋 zr贸偶nicowanym sk艂adem chemicznym pod wzgl臋dem zawarto艣ci celulozy, ligniny czy substancji nieorganicznych, co jest istotnym elementem wp艂ywaj膮cym na mo偶liwo艣膰 wyodr臋bnienia z nich w艂贸kien celulozowych. Wybrane surowce ro艣linne poddano obr贸bce termiczno-mechaniczno-chemicznej, w wyniku kt贸rej w r贸偶nym stopniu nast臋powa艂o oczyszczenie biomasy od z niecelulozowych sk艂adnik贸w (ligniny, hemicelulozy i pektyn) oraz przygotowanie surowca celulozowego o za艂o偶onej strukturze i w艂a艣ciwo艣ciach niezb臋dnych do ich przerobu na formy nanow艂贸kniste

    Wyodr臋bnianie galaktoglukomannan贸w (GGM) z krajowych odmian drzew iglastych

    No full text
    The article presents a method of extracting galactoglucomannans from conifers: spruce and larch. Galactoglucomannans (GGMs) were extracted from shavings of Polish varieties of spruce and larch, using thermal and enzymatic treatment in an aqueous environment. The composition of the extracted GGMs (depending on the extraction method) was characterized by varied content of individual monosaccharides, i.e. glucose, galactose and mannose, as well as the average particle mass. The quantitative and qualitative composition of the extracted GGMs is an important factor affecting the possibility of their wide employment in modifying cellulose fibre-containing materials in order to improve their barrier qualities, and as biological agents in plant health products. GC/MS and SEC chromatographic tests and 13C NMR analysis made it possible to establish the composition and structural changes of the acquired GGMs.W artykule przedstawiono spos贸b wyodr臋bniania galaktoglukomannan贸w z drzew iglastych: 艣wierku i modrzewia. Galaktoglukomannany (GGM) wyodr臋bniono z trocin drzewnych krajowych odmian 艣wierku i modrzewia z zastosowaniem obr贸bki termicznej i enzymatycznej w 艣rodowisku wodnym. Wyodr臋bnione GGM (w zale偶no艣ci od metody wyodr臋bniania) charakteryzowa艂y si臋 zr贸偶nicowanym sk艂adem pod wzgl臋dem zawarto艣ci poszczeg贸lnych cukr贸w prostych tj. glukozy, galaktozy i mannozy oraz warto艣ci膮 艣redniej masy cz膮steczkowej. Sk艂ad ilo艣ciowy i jako艣ciowy wyodr臋bnionych GGM jest istotnym elementem wp艂ywaj膮cym na mo偶liwo艣膰 ich szerokiego zastosowania do modyfikacji materia艂贸w zawieraj膮cych w艂贸kna celulozowe w celu polepszenia ich w艂a艣ciwo艣ci barierowych oraz jako czynniki czynnik贸w biologicznych dla 艣rodk贸w ochrony ro艣lin. Badania z wykorzystaniem chromatografii GC/MS, SEC oraz analiza 13C NMR pozwoli艂y oceni膰 sk艂ad i zmiany strukturalne otrzymanych GGM

    Wykorzystanie cieczy maceracyjnej pozosta艂ej z enzymatycznego roszenia Spartium junceum do biosyntezy nanocelulozy bakteryjnej

    No full text
    The idea of the production of high value-added materials from wastes originating from renewable plant biomass has great potential of becoming an integral part of modern biorefineries. Spartium junceum (Spanish broom) is a perennial shrub widespread in the Mediterranean area. Since ancient times it has been used as a raw material for the manufacture of ropes, nets, bags, sails and even high quality yarns, fabric and garments. Waste post-maceration liquid (PML) from Spanish broom enzymatic retting was utilized as a component of different culture media in the biosynthesis of bacterial nanocellulose (BNC) by Gluconacetobacter xylinus (ATCC 700178). The results of the experiments showed that it is possible to use post-maceration liquid as a medium component for the biosynthesis of BNC. It was also possible to reduce the cost of biosynthesis by elimination or reduction of the amount of individual medium components and to obtain BNC with a comparable or higher yield than in the standard culture medium.Wytwarzanie materia艂贸w o wysokiej warto艣ci dodanej z odpad贸w powstaj膮cych z przetw贸rstwa odnawialnej biomasy ro艣linnej zwi膮zane jest 艣ci艣le z ide膮 nowoczesnych biorafinerii. Spartium junceum jest wieloletnim krzewem szeroko rozpowszechnionym w basenie Morza 艢r贸dziemnego. Od czas贸w staro偶ytnych wykorzystywany by艂 jako surowiec do wytwarzania lin, sieci, work贸w, 偶agli a nawet prz臋dz i tkanin ubraniowych. W celu efektywnego wydzielania w艂贸kien z ga艂膮zek Spartium junceum w艂oski instytut badawczy ARTES wyizolowa艂 szczepy mikroorganizm贸w produkuj膮ce wyspecjalizowane enzymy oraz opracowa艂 proces enzymatycznego roszenia w艂贸knodajnej ro艣liny z wykorzystaniem opatentowanej mieszanki enzym贸w o nazwie GINEXTRA庐. Odpadowa ciecz po maceracji (PML) zosta艂a wykorzystana jako sk艂adnik ciek艂ych pod艂o偶y hodowlanych w procesie biosyntezy nanocelulozy bakteryjnej (BNC) z udzia艂em szczepu Gluconacetobacter xylinus (ATCC 700178). Badania wykaza艂y, 偶e odpadowa ciecz maceracyjna mo偶e z powodzeniem zast膮pi膰 wod臋 w pod艂o偶u hodowlanym. Dodatkowymi zaletami s膮: obni偶enie koszt贸w biosyntezy BNC przez ca艂kowite wyeliminowanie lub ograniczenie ilo艣ci drogich sk艂adnik贸w pod艂o偶a i otrzymanie nanocelulozy bakteryjnej z wydajno艣ci膮 por贸wnywaln膮 lub nawet wy偶sz膮 ni偶 przy zastosowaniu standardowego pod艂o偶a

    Establishing and Operating (Pilot Phase) a Telemetric Streamflow Monitoring Network in Greece

    No full text
    This paper describes HYDRONET, a telemetry-based prototype of a streamflow monitoring network in the Greek territory, where such data are sparse. HYDRONET provides free and near-real-time online access to data. Instead of commercially available stations, in-house-designed and -built telemetric stations were installed, which reduced the equipment cost by approximately 50%. The labour of hydrometric campaigns was reduced by applying a new maximum-entropy method to estimate the discharge from surface velocity observations. Here, we describe these novelty elements succinctly. The potential of HYDRONET to provide civil protection services is exemplified by a flood warning demonstrator for Kalamata鈥檚 City Centre. The network鈥檚 operation, including the hydraulic criteria for monitoring site selection, the characteristics of the telemetric equipment, the operational monitoring and hydrometric procedures, and the specifics of data transmission, quality control, and storage are described in detail, along with experiences with problems encountered during this pilot phase
    corecore