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181.
In this work, we compared the proteome of mature and immature kernels of transgenic and untransformed durum wheat lines in which genes of the starch branching enzymes of class II (SBEIIa) were silenced by RNA interference using two different methods of genetic transformation. The comparative analysis of granule bound and metabolic protein fractions of Svevo and Ofanto and their derived transgenic lines highlighted twenty four and thirty three differentially accumulated spots, respectively, in the line MJ16-112 (obtained by biolistic transformation of Svevo) and in the line A431_4p1a (obtained by Agrobacterium-mediated transformation of Ofanto).  相似文献   
182.
Journal of Pest Science - A correction to this paper has been published: https://doi.org/10.1007/s10340-021-01393-0  相似文献   
183.
Using high resolution molecular technique of atomic force microscopy, we address the extracellular polymer production of Adriatic diatom Cylindrotheca closterium analyzed at the single cell level and the supramolecular organization of gel phase isolated from the Northern Adriatic macroaggregates. Our results revealed that extracellular polysaccharides freshly produced by marine diatoms can self-assemble directly to form gel network characteristics of the macroscopic gel phase in the natural aquatorium. Based on the experiments performed with isolated polysaccharide fractions of C. closterium and of macroaggregates gel phase, we demonstrated that the polysaccharide self-assembly into gel network can proceed independent of any bacterial mediation or interaction with inorganic particles.  相似文献   
184.
Neurological and locomotor clinical signs are described in animals infected with Trypanosoma evansi. These disturbances may be related to changes in the amount of acetylcholine (neurotransmitter) in the synaptic cleft. Therefore, changes in acetylcholinesterase (AChE) activity and lipid peroxidation in brain and spinal cord of T. evansi-infected rats were investigated. Each rat was intraperitoneally infected with 10(6) trypomastigotes kept in fresh (group A; n=13) and cryopreserved blood (group B; n=13). Thirteen served as uninfected (not-infected; group C). In days 4 and 30 post-infection (PI) the rats were anesthetized and subsequently decapitated to obtain the brain and the spinal cord (between vertebrae L1 and S2). The brain was removed and dissected (cerebellum, cerebral cortex, striatum and hippocampus) to measure the activity of AChE and lipid peroxidation, determined by TBARS levels. To verify if T. evansi was present in the central nervous system (CNS), brain structures of three rats of each group were processed by PCR T. evansi-specific. AChE activity was significantly increased in all brain structures and decrease in spinal cord in infected rats in 4 PI (P<0.05). The levels of TBARS were decreased in the brain structures, differently from spinal cord, which showed increased lipid peroxidation in 4 PI. The AChE activity in striatum, cerebral cortex, hippocampus and spinal cord reduced concomitantly with the increase of the enzyme in cerebellum of the infected rats (P<0.05), and the TBARS levels increased in cerebellum, striatum and spinal cord of infected rats compared to non-infected animals in 30 PI. The PCR was positive for T. evansi in all structures of the brain, confirming the presence of the parasite in the CNS. Based on the results, we conclude that the changes in AChE activity and lipid peroxidation in the CNS are induced by infection with T. evansi, suggesting that the parasite interferes with the cholinergic neurotransmission in this experimental condition.  相似文献   
185.
The sensorial representativeness of the headspace solid-phase microextraction (HS-SPME) aroma extract from commercial Sherry vinegars has been determined by direct gas chromatography-olfactometry (D-GCO). Extracts obtained under optimal conditions were used to characterize the aroma of these vinegars by means of GCO and aroma extract dilution analysis (AEDA). Among the 37 different odorants determined, 13 of them were identified for the first time in Sherry vinegars: 2 pyrazines (3-isopropyl-2-methoxypyrazine, 3-isobutyl-2-methoxypyrazine), 2 sulfur compounds (methanethiol, dimethyl trisulfide), 1 unsaturated ketone (1-octen-3-one), 1 norisoprenoid (β-damascenone), 1 ester (ethyl trans-cinnamate) and 6 aldehydes (2- and 3-methylbutanal, octanal, nonanal, (E)-2-nonenal and (E,E)-2,4-decadienal). The determination of the odor thresholds in a hydroacetic solution together with the quantitative analysis-which was also performed using the simple and fast SPME technique-allowed obtaining the odor activity values (OAV) of the aromatic compounds found. Thus, a first pattern of their sensory importance on commercial Sherry vinegar aroma was provided.  相似文献   
186.
Seasonal differences in the resumption of postpartum ovarian activity, milk production and periparturient metabolic status were investigated in lactating non-suckling dairy Awassi sheep in two consecutive experiments. In Experiment 1, autumn-lambing (AL, n = 27) and spring-lambing (SL, n = 37) ewes were investigated. Ovarian activity was monitored by means of individual progesterone (P4) profiles from day 5 to day 100 post partum. Most of the AL dams (89%) ovulated till day 35 after parturition and became cyclic thereafter. Incidence of persistent corpus luteum (CLP) and short luteal phases (sCL) was frequent (18% and 29%, respectively) among non-conceiving dams. In contrast, only 24% of the SL ewes ovulated before day 35. P4 levels during the luteal phase were lower in cyclic animals, and the cycle was longer in SL than in AL animals. No CLP or sCL was detected in the spring-lambing group, and 61% of SL ewes remained acyclic till the end of the trial. Lactation length was significantly longer in SL dams than in AL ewes (P = 0.008). According to the plasma metabolites (BHB, NEFA) and metabolic hormones (insulin, IGF-I, thyroxine) examined, negative energy balance did not appear in any of the animals. However, seasonal differences were seen in IGF-I and thyroxine levels, which were higher in the SL dams. In Experiment 2, influence of additional lighting was studied in autumn-lambing ewes. The long-day photoperiod (LD, n = 23) group was exposed to artificial light from sunset till midnight (approx. 16 h light/8 h dark) from some weeks before the expected date of delivery in mid-September until the end of December. The control group (n = 25) experienced only natural daylength. The first postpartum ovulation tended to occur later in the LD animals than in the controls (P = 0.047). The lactation of the LD group tended to be longer (P = 0.061). NEFA, BHB, insulin, IGF-I and thyroxine levels did not differ between the groups. Conclusions: (i) The ovarian function of the Awassi population is seasonal under temperate continental climate conditions. (ii) The first postpartum ovulation of non-suckling, autumn-lambing dams may occur very early, even before the completion of uterine involution. (iii) Additional artificial lighting may delay the time of first postpartum ovulation in AL ewes. (iv) Postpartum negative energy balance is unlikely to occur in dairy Awassi ewes even in high-producing intensive systems.  相似文献   
187.
SIRT6 promotes DNA repair under stress by activating PARP1   总被引:2,自引:0,他引:2  
Sirtuin 6 (SIRT6) is a mammalian homolog of the yeast Sir2 deacetylase. Mice deficient for SIRT6 exhibit genome instability. Here, we show that in mammalian cells subjected to oxidative stress SIRT6 is recruited to the sites of DNA double-strand breaks (DSBs) and stimulates DSB repair, through both nonhomologous end joining and homologous recombination. Our results indicate that SIRT6 physically associates with poly[adenosine diphosphate (ADP)-ribose] polymerase 1 (PARP1) and mono-ADP-ribosylates PARP1 on lysine residue 521, thereby stimulating PARP1 poly-ADP-ribosylase activity and enhancing DSB repair under oxidative stress.  相似文献   
188.
189.
  • 1. Over the past two decades the number of fisheries targeting shark resources has increased dramatically. A combination of factors, including relatively slow growth rate, low fecundity and late age of maturity, result in low recovery rates from exploitation for most shark species. This, in turn, is reflected in the poor record of sustainability of shark fisheries.
  • 2. One of the greatest challenges is to find a way to deal with the substantial levels of shark bycatch taken in many non‐target fisheries. Poor general recording of shark landings and paucity of shark landing data at the species level also undermine the development of effective shark management strategies. 3. This paper reviews the problems that must be faced worldwide if shark resources are to be managed sustainably and lays out a comprehensive set of prioritized management strategies to facilitate the sustainable management of global shark fisheries. It is acknowledged that the majority of sharks are harvested in developing countries and that the management of shark resources in developing and developed countries will need to incorporate different management strategies relevant to local socio‐economic agendas. The management recommendations deal with methods to improve the global regulation of fisheries, ways to improve global conservation ethics and encourage active participation in management, as well as means by which specific management strategies may be implemented.
Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
190.
The illness of three people due to diarrhetic shellfish poisoning (DSP) following their ingestion of recreationally harvested mussels from Sequim Bay State Park in the summer of 2011, resulted in intensified monitoring for diarrhetic shellfish toxins (DSTs) in Washington State. Rapid testing at remote sites was proposed as a means to provide early warning of DST events in order to protect human health and allow growers to test “pre-harvest” shellfish samples, thereby preventing harvest of toxic product that would later be destroyed or recalled. Tissue homogenates from several shellfish species collected from two sites in Sequim Bay, WA in the summer 2012, as well as other sites throughout Puget Sound, were analyzed using three rapid screening methods: a lateral flow antibody-based test strip (Jellett Rapid Test), an enzyme-linked immunosorbent assay (ELISA) and a protein phosphatase 2A inhibition assay (PP2A). The results were compared to the standard regulatory method of liquid chromatography coupled with tandem mass spectroscopy (LC-MS/MS). The Jellett Rapid Test for DSP gave an unacceptable number of false negatives due to incomplete extraction of DSTs using the manufacturer’s recommended method while the ELISA antibody had low cross-reactivity with dinophysistoxin-1, the major toxin isomer in shellfish from the region. The PP2A test showed the greatest promise as a screening tool for Washington State shellfish harvesters.  相似文献   
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