703 research outputs found

    Production of callus from protoplasts of cultured grape pericarp

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    Protoplasts were isolated from callus cultures of grape vine pericarp after an overnight incubation at 26 °c in 2% Cellulase Onozuka SS plus 1 % Macerozyme dissolved in a mixture of 0.14 molal KCl and 0.10 molal CaCl2 at pH 5.5. When cultured in a liquid medium with either 0.24 M sorbitol or 0.23 M sucrose as osmotic stabilizer, new cell walls were regenerated within the first few days. Cell division commenced by the sixth day of culture, and approximately 0.5% of the population continued dividing. Eventual transfer of the culture to the surface of medium solidified with agar resulted in callus formation.Kallusbildung aus Protoplasten von kultiviertem TraubenperikarpEine Nährlösung wird beschrieben, in der Protoplasten, die aus Kalluskulturen von Traubenperikarp isoliert worden waren, neue Zellwände bildeten und Zellteilungen eingingen. Spätere Übertragung auf einen festen Nährboden ergab aktives Kalluswachstum

    In vitro propagation of grapevine (Vitis vinifera L.) from fragmented shoot apices

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    A method is described for the in vitro propagation of grapevine from fragmented shoot apices, which has the potential to produce approximately 8000 plantlets from a single apex within 4 months. Apical cell clumps were grown in a liquid culture medium with cytokinin but in the absence of auxin. Transfer of the differentiated cell clumps to the same medium gelled with agar resulted in shoot masses which could be repeatedly subcultured. Excised shoots rooted readily on a hormone-free basal medium, and were successfully transferred to glasshouse conditions. This method has potential value in commercial clonal grapevine propagation.In-vitro-Vermehrung der Rebe (Vitis vinifera L.) aus zerstückelten TriebspitzenEine Methode für die in-vitro-Vermehrung der Rebe aus zerstückelten Triebspitzen wird beschrieben. Zellklumpen der Triebspitze wurden auf einem flüssigen Medium, das Cytokinin, aber kein Auxin enthielt, kultiviert. Nach Übertragung der differenzierten Zellklumpen auf ein mit Agar verfestigtes, aber sonst gleich zusammengesetztes Medium entstanden Büschel von Trieben, die zerteilt und weiter vermehrt werden konnten. Explantierte Einzeltriebe bewurzelten sich auf einem hormonfreien Grundmedium rasch

    Ploidy stability in grapevines following long term storage in vitro

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    A modified method to prepare root tip squashes was used for the routine examination of chromosomes of grapevines developed from in vitro shoot cultures. The results established that adventitious buds obtained by culture of fragmented shoot apices were diploid, and that storage at 9.5 °C of multiple shoot cultures of eight Vitis genotypes for periods up to 12 months did not affect the ploidy level of plants regenerated from them

    Partial characterization of Agrobacterium vitis strains

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    Seventeen strains of Agrobacterium vitis (formerly classified A. tumefaciens biovar 3) were characterized using part of the T-DNA and virA regions of the Ti plasmid as probes. All strains except one were of the wide host range (WHR) strains and were classified into two groups depending on their ability to utilize octopine or nopaline. These WHR type oncogenic strains had homology with the limited host range type (LHR) virA gen of A. vitis but not with the WHR virA gene of A. tumefaciens. The frequency of T-DNA excision in some Agrobacterium strains was estimated with the plasmid pTMA which mimics T-DNA excision from Ti plasmid DNA. In an A. vitis strain isolated from grapevine, T-DNA excision occurred after co-cultivation with grapevine tissues, but not with acetosyringone. In contrast, in A. tumefaciens, T-DNA excision occurred after co-cultivation with acetosyringone, but not with grapevine tissue

    Effect of Root Temperature on Cytokinin Activity in Root Exudate of Vitis vinifera

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    Dilatation in the femoral vascular bed does not cause retrograde relaxation of the iliac artery in the anaesthetized pig

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    Aim:  We tested the hypothesis that dilatation of a feeding artery may be elicited by transmission of a signal through the tissue of the arterial wall from a vasodilated peripheral vascular bed. Methods:  In eight pentobarbital anaesthetized pigs, acetylcholine (ACh, an endothelium-dependent vasodilator) was injected intra-arterially above (upstream) and below (downstream) a test segment of the left iliac artery, the diameter of which was measured continuously by sonomicrometry. Results:  Under control conditions, ACh injections upstream and downstream of the test segment caused dilatation. Downstream injection dilated the peripheral arterioles, resulting in increased blood flow and proximal dilatation. This is a shear stress, nitric oxide (NO)-dependent response. The experiment was then repeated after applying a stenosis to prevent the increased flow caused by downstream injection of ACh; the stenosis was placed either above the site of diameter measurement to allow retrograde conduction, or below that site to prevent distally injected ACh reaching the measurement site. Under these conditions, downstream injection of ACh had a minimal effect on the shear stress of the test segment with no increase in test segment diameter. This was not due to endothelial damage or dysfunction as injection of ACh upstream still caused a large increase in test segment diameter. Conclusions:  Our results indicate that dilatation of the feeding artery of a vasodilated bed is caused by increased shear stress within the feeding artery and not via a signal transmitted through the arterial wall from below

    Pain assessment tools in paediatric palliative care: A systematic review of psychometric properties and recommendations for clinical practice

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    Background: Assessing pain in infants, children and young people with life-limiting conditions remains a challenge due to diverse patient conditions, types of pain and often a reduced ability or inability of patients to communicate verbally. Aim: To systematically identify pain assessment tools that are currently used in paediatric palliative care and examine their psychometric properties and feasibility and make recommendations for clinical practice. Design: A systematic literature review and evaluation of psychometric properties of pain assessment tools of original peer-reviewed research published from inception of data sources to April 2021. Data sources: PsycINFO via ProQuest, Web of Science Core, Medline via Ovid, EMBASE, BIOSIS and CINAHL were searched from inception to April 2021. Hand searches of reference lists of included studies and relevant reviews were performed. Results: From 1168 articles identified, 201 papers were selected for full-text assessment. Thirty-four articles met the eligibility criteria and we examined the psychometric properties of 22 pain assessment tools. Overall, the Faces Pain Scale-Revised (FPS-R) had high cross-cultural validity, construct validity (hypothesis testing) and responsiveness; while the Faces, Legs, Activity, Cry and Consolability (FLACC) scale and Paediatric Pain Profile (PPP) had high internal consistency, criterion validity, reliability and responsiveness. The number of studies per psychometric property of each pain assessment tool was limited and the methodological quality of included studies was low. Conclusion: Balancing aspects of feasibility and psychometric properties, the FPS-R is recommended for self-assessment, and the FLACC scale/FLACC Revised and PPP are the recommended observational tools in their respective age groups

    THE INFLUENCE OF THE VARIOUS TEMPERATURES ON THE PUPAS OF MEDITERRANEAN FRUITFLY AND ON THE EARLY DEVELOPMENT OF PLASE OPIUS CONCOLORA SZEPL

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    The identification and investigation of novel clock-controlled genes (CCGs) has been conducted thus far mainly in model organisms such as nocturnal rodents, with limited information in humans. Here, we aimed to characterize daily and circadian expression rhythms of CCGs in human peripheral blood during a sleep/sleep deprivation (S/SD) study and a constant routine (CR) study. Blood expression levels of 9 candidate CCGs (SREBF1, TRIB1, USF1, THRA1, SIRT1, STAT3, CAPRIN1, MKNK2, and ROCK2), were measured across 48 h in 12 participants in the S/SD study and across 33 h in 12 participants in the CR study. Statistically significant rhythms in expression were observed for STAT3, SREBF1, TRIB1, and THRA1 in samples from both the S/SD and the CR studies, indicating that their rhythmicity is driven by the endogenous clock. The MKNK2 gene was significantly rhythmic in the S/SD but not the CR study, which implies its exogenously driven rhythmic expression. In addition, we confirmed the circadian expression of PER1, PER3, and REV-ERBα in the CR study samples, while BMAL1 and HSPA1B were not significantly rhythmic in the CR samples; all 5 genes previously showed significant expression in the S/SD study samples. Overall, our results demonstrate that rhythmic expression patterns of clock and selected clock-controlled genes in human blood cells are in part determined by exogenous factors (sleep and fasting state) and in part by the endogenous circadian timing system. Knowledge of the exogenous and endogenous regulation of gene expression rhythms is needed prior to the selection of potential candidate marker genes for future applications in medical and forensic settings

    Genetic influences on social attention in free-ranging rhesus macaques

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    An ethological approach to attention predicts that organisms orient preferentially to valuable sources of information in the environment. For many gregarious species, orienting to other individuals provides valuable social information but competes with food acquisition, water consumption and predator avoidance. Individual variation in vigilance behaviour in humans spans a continuum from inattentive to pathological levels of interest in others. To assess the comparative biology of this behavioural variation, we probed vigilance rates in free-ranging macaques during water drinking, a behaviour incompatible with the gaze and postural demands of vigilance. Males were significantly more vigilant than females. Moreover, vigilance showed a clear genetic component, with an estimated heritability of 12%. Monkeys carrying a relatively infrequent ‘long’ allele of TPH2, a regulatory gene that influences serotonin production in the brain, were significantly less vigilant compared to monkeys that did not carry the allele. These findings resonate with the hypothesis that the serotonin pathway regulates vigilance in primates and by extension provoke the idea that individual variation in vigilance and its underlying biology may be adaptive rather than pathological
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