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51.
The development of drugs able to target BTK, PI3k‐delta and BCL2 has dramatically improved chronic lymphocytic leukaemia (CLL) therapies. However, drug resistance to these therapies has already been reported due to non‐recurrent changes in oncogenic pathways and genes expression signatures. In this study, we investigated the cooperative role of the BCL2 inhibitor venetoclax and the BRD4 inhibitor JQ1. In particular, we found that JQ1 shows additional activity with venetoclax, in CLL cell lines and in ex vivo isolated primary CD19+ lymphocytes, arguing in favour of combination strategies. Lastly, JQ1 is also effective in venetoclax‐resistant CLL cell lines. Together, our findings indicated that the BET inhibitor JQ1 could be a promising therapy in CLL, both as first‐line therapy in combination with venetoclax and as second‐line therapy, after the emergence of venetoclax‐resistant clones.  相似文献   
52.
The Envelope protein (E) is one of the four structural proteins encoded by the genome of SARS‐CoV and SARS‐CoV‐2 Coronaviruses. It is an integral membrane protein, highly expressed in the host cell, which is known to have an important role in Coronaviruses maturation, assembly and virulence. The E protein presents a PDZ‐binding motif at its C‐terminus. One of the key interactors of the E protein in the intracellular environment is the PDZ containing protein PALS1. This interaction is known to play a key role in the SARS‐CoV pathology and suspected to affect the integrity of the lung epithelia. In this paper we measured and compared the affinity of peptides mimicking the E protein from SARS‐CoV and SARS‐CoV‐2 for the PDZ domain of PALS1, through equilibrium and kinetic binding experiments. Our results support the hypothesis that the increased virulence of SARS‐CoV‐2 compared to SARS‐CoV may rely on the increased affinity of its Envelope protein for PALS1.  相似文献   
53.
Plant and Soil - Data about woody debris (WD) decomposition are very scarce for the Mediterranean basin. The specific aim of this work is to explore the relationships between WD traits with the...  相似文献   
54.

Benthic surveys are a key component of monitoring and conservation efforts for coral reefs worldwide. While traditional image-based surveys rely on manual annotation of photographs to characterise benthic composition, automatic image annotation based on computer vision is becoming increasingly common. However, accurate classification of some benthic groups from reflectance images presents a challenge to local ecologists and computers alike. Most coral reef organisms produce one or a combination of fluorescent pigments, such as Green Fluorescent Protein (GFP)-like proteins found in corals, chlorophyll-a found in all photosynthetic organisms, and phycobiliproteins found in red macroalgae, crustose coralline algae (CCA) and cyanobacteria. Building on the potential of these pigments as a target for automatic image annotation, we developed a novel imaging method based on off-the-shelf components to improve classification of coral and other biotic substrates using a multi-excitation fluorescence (MEF) imaging system. We used RGB cameras to image the fluorescence emission of coral and algal pigments stimulated by narrow-waveband blue and green light, and then combined the information into three-channel pseudocolour images. Using a set of a priori rules defined by the relative pixel intensity produced in different channels, the method achieved successful classification of organisms into three categories based on the dominant fluorescent pigment expressed, facilitating discrimination of traditionally problematic groups. This work provides a conceptual foundation for future technological developments that will improve the cost, accuracy and speed of coral reef surveys.

  相似文献   
55.
Somatic embryogenesis of Abies alba (Mill.) has significant potential to become an effective method for vegetative propagation of this species. To induce somatic embryogenesis in A. alba, the influence of the mother tree, sampling dates, and cold treatment storage of cones were examined. The initiation frequencies ranged from 1.7% to 16.6%. The sampling date and cone storage, but not the mother tree, had a significant effect on the initiation of embryogenic cultures. Storage of embryogenic cell lines was tested through cryopreservation for 6 yr. Four out of 12 cryostored embryogenic cell lines recovered, and the regeneration of cotyledonary embryos was obtained with two cell lines. The ability of embryogenic cell masses to produce somatic embryos and the mean number of cotyledonary embryos were higher when the maturation protocol was based on embryogenic suspensions dispersed on filter paper. The properly developed germinants were obtained only from maturation media where 32 μM abscisic acid was used, being 16.2% when polyethylene glycol (PEG) was not present and 1.8% when supplemented with 10% (w/v) PEG, respectively. The present study provides evidence that it is possible to cryopreserve A. alba embryogenic cultures while maintaining their maturing ability for the lengthy period (6 yr) needed for progeny testing of field-grown trees. Therefore, our findings are important for further studies and advanced breeding work of the species; however, the conversion of germinants into ex vitro conditions still remains a significant challenge.  相似文献   
56.
Psyttalia concolor (Szépligeti) is a koinobiont larval-pupal endoparasitoid of many Tephritidae of great economic importance, such as the medfly, Ceratitis capitata (Wiedemann). In several species of parasitoids it has been demonstrated that the mated females are strongly attracted by specific volatiles from insect-damaged plants. Yet the role of olfactory cues deriving from C. capitata-infested fruits on the female’s decision during the P. concolor host location was poorly investigated. In the present study, the responses of P. concolor females to either healthy or C. capitata-infested fruits was studied through behavioral assays. Volatiles emitted by healthy and infested fruits were SPME-sampled and analyzed by gas chromatography–mass spectrometry (GC–MS). The attractiveness of the identified volatiles was assessed and their electrophysiological activity was analyzed through gas-chromatography coupled with electroantennography (GC-EAD). P. concolor preferred infested peaches and apples over healthy ones, either when visual and olfactory or only olfactory cues were given. Nine compounds were found as exclusive of infested peaches, with respect to healthy ones, and seven of them evoked electrophysiological responses. In apples only quantitative changes in volatile emissions were observed after the medfly infestation. The emissions of 1-butyl butylate, 1-hexyl acetate and 1-butyl esanoate increased in infested apples, whereas 1-hexyl (E)-2-methyl butenoate decreased significantly. Among apple volatiles, 1-butyl butylate, 2-methyl-1-butyl acetate, 1-hexyl acetate, 2-methyl-1-butyl 2-methylbutanoate, 1-butyl hexanoate and 1-hexyl (E)-2-methyl butenoate elicited responses in female antennae. Synthetic blends reproducing the odors emitted by infested peaches and apples elicited strong attraction towards P. concolor females. For both fruits, the blend attractiveness was mainly due to some specific electrophysiological active chemicals: ethyl octanoate, decanal and 4-decanolide for peach, and 1-butyl butylate and 1-butyl hexanoate for apple. The responses induced by the identified fruit volatiles to P. concolor females allow us to suppose that they play a role as short-range attractants during host location.  相似文献   
57.
Using an optoelectronic motion capture system, we quantitatively assessed the arrangement of body segments and the displacement of the horizontal projection of the center of mass (CM) in seven skaters performing off-ice back spins on a rotating device (spinner). The position of the CM at the beginning of the spins was not a determining factor, but its rapid stabilization towards the center of the spinner, together with the achievement of a stable arrangement of trunk and limbs, was crucial to get the dynamic equilibrium, necessary for a lasting performance. At full spinning, however, there was an indicative variety of individual body postures. A final deceleration, associable with the loss of body equilibrium, was detected in the last spin of most of skaters.In conclusion, the current investigation demonstrated that the off-ice execution of back spin, a critical movement of ice skating, can be measured in laboratory, thus providing quantitative information to both the skaters and the coaches. The analysis is not invasive, and it may be proposed also for longitudinal evaluations of skating and postural training.  相似文献   
58.
The methods for symmetry line detection presented in the literature are typically suited to analyse symmetric upright postures, both standing and seated. The proposed method focuses on the symmetry line detection in subjects assuming asymmetric postures in which this line falls far outside the sagittal plane. The proposed approach evaluates the symmetry line by means of an autoregressive process in order to determine the set of planes suited to slice the back coherently with its geometric spatial configuration. The method is analysed assuming the cutaneous marking as reference and it is compared with a previous one, also developed by these authors. Results are analysed and critically discussed.  相似文献   
59.
Abstract

The discover and morphological characters of a Dematiaceous Hyphomycetes are described. The material, studied under a morphological point of view directly collected on the natural substratum, allows us to establish the appartenance to the genus Chaetopsina. Since this species does not appeare described till now, the Authors propose for it the nomenclature ivoriensis as a new species.  相似文献   
60.
Costs of sexual interactions play a key role in life‐history evolution. Although the costs of reproduction have been investigated in both sexes of many insects, the costs of same‐sex interactions have been examined in few species. In parasitic wasps, very little has been reported about the longevity costs of heterosexual interactions, and nothing is known about longevity costs of same‐sex interactions. In this study, the effects of heterosexual and homosexual activities on longevity were evaluated in Psyttalia concolor (Hymenoptera: Braconidae), a synovigenic koinobiont larval‐pupal endoparasitoid of tephritid flies. When compared with individually housed virgin wasps, male longevity was strongly reduced both in males kept with females, and in males kept with other males. When females were kept with males, their longevity was reduced compared with the virgin females and females kept with other females. Overall, the costs of male–female interactions were considerable in both sexes of P. concolor, while same‐sex activities were found to be costly only among males, suggesting that they may have implications for the evolution of the P. concolor mating system.  相似文献   
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