504 research outputs found

    Effects of abscisic acid on ethylene biosynthesis and perception in Hibiscus rosa-sinensis L. flower development

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    The effect of the complex relationship between ethylene and abscisic acid (ABA) on flower development and senescence in Hibiscus rosa-sinensis L. was investigated. Ethylene biosynthetic (HrsACS and HrsACO) and receptor (HrsETR and HrsERS) genes were isolated and their expression evaluated in three different floral tissues (petals, style\u2013stigma plus stamens, and ovaries) of detached buds and open flowers. This was achieved through treatment with 0.1 mM 1-aminocyclopropane-1-carboxylic acid (ACC) solution, 500 nl l21 methylcyclopropene (1-MCP), and 0.1 mM ABA solution. Treatment with ACC and 1-MCP confirmed that flower senescence in hibiscus is ethylene dependent, and treatment with exogenous ABA suggested that ABA may play a role in this process. The 1-MCP impeded petal in-rolling and decreased ABA content in detached open flowers after 9 h. This was preceded by an earlier and sequential increase in ABA content in 1-MCP-treated petals and style\u2013stigma plus stamens between 1 h and 6 h. ACC treatment markedly accelerated flower senescence and increased ethylene production after 6 h and 9 h, particularly in style\u2013stigma plus stamens. Ethylene evolution was positively correlated in these floral tissues with the induction of the gene expression of ethylene biosynthetic and receptor genes. Finally, ABA negatively affected the ethylene biosynthetic pathway and tissue sensitivity in all flower tissues. Transcript abundance of HrsACS, HrsACO, HrsETR, and HrsERS was reduced by exogenous ABA treatment. This research underlines the regulatory effect of ABA on the ethylene biosynthetic and perception machinery at a physiological and molecular level when inhibitors or promoters of senescence are exogenously applied

    Chlorophyll a Fluorescence as a Tool in Evaluating the Effects of ABA Content and Ethylene Inhibitors on Quality of Flowering Potted Bougainvillea

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    Flowering potted plants during the postproduction stage are usually stored in inadequate environmental conditions. We evaluated the effect of the most common storage conditions and treatments on two Bougainvillea cultivars after harvest and during recovery. Flowering potted Bougainvillea plants were treated with 100 mL 2 mM amino-oxyacetic acid (AOA) or 500 ppb 1-methylcyclopropene (1-MCP) prior storage in dark at 14°C for simulating transport or storage conditions and, subsequently, transferred to growth chambers at 20°C in the light for one week for evaluating the recovery ability. The plant stress during the experiments was assessed by ethylene, ABA, and chlorophyll a fluorescence measurements. Ethylene production was affected by temperature rather than treatments. ABA concentration declined in leaves and flowers during storage and was not affected by treatments. Fluorescence parameters appear to be very useful for screening Bougainvillea cultivars resistant to prolonged storage periods

    Spatial and temporal distribution of mineral nutrients and sugars throughout the lifespan of Hibiscus rosa-sinensis L. flower

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    AbstractAlthough the physiological and molecular mechanisms of flower development and senescence have been extensively investigated, a whole-flower partitioning study of mineral concentrations has not been carried out. In this work, the distribution of sucrose, total reducing sugars, dry and fresh weight and macro and micronutrients were analysed in Hibiscus rosa-sinensis L. petals, stylestigma including stamens and ovary at different developmental stages (bud, open and senescent flowers). Total reducing sugars showed the highest value in petals of bud flowers, then fell during the later stages of flower development whereas sucrose showed the highest value in petals of senescent flowers. In petals, nitrogen and phosphorus content increased during flower opening, then nitrogen level decreased in senescent flowers. The calcium, phosphorus and boron concentrations were highest in ovary tissues whatever the developmental stage. Overall, the data presented suggests that the high level of total reducing sugars prior the onset of flower opening contributes to support petal cells expansion, while the high amount of sucrose at the time of petal wilting may be viewed as a result of senescence. Furthermore, this study discusses how the accumulation of particular mineral nutrients can be considered in a tissue specific manner for the activation of processes directly connected with reproduction

    Focus on therapy of hypnic headache

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    Hypnic headache (HH) is a primary headache disorder, which occurs exclusively during sleep and usually begins after 50 years of age. There are no controlled trials for the treatment of HH. We reviewed all the available papers, including 119 cases published in literature up to date, reporting the efficacy of the medications used to treat HH. Acute treatment is not recommended, since no drug proved to be clearly effective and also because the intensity and the duration of the attacks do not require the intake of a medication in most cases. As for prevention, a wide variety of medications were reported to be of benefit in HH. The drugs that were found to be effective in at least five cases are: lithium, indomethacin, caffeine and flunarizine. Lithium was the most extensively studied compound and demonstrated to be an efficacious treatment in 32 cases. Unfortunately, despite its efficacy, significant adverse effects and poor tolerability are not rare, mainly in elderly patients. Many patients reported a good response to indomethacin, but some could not tolerate it. Caffeine and melatonin treatments did not yield robust evidence to recommend their use as single preventive agents. Nevertheless, their association with lithium or indomethacin seems to produce an additional therapeutic efficacy. A course of lithium should be tried first, followed 3–4 months later by tapering. If headache recurs during tapering, a longer duration of therapy may be needed. If lithium treatment does not provide a significant response, indomethacin can be commenced as second-line approach. If these treatments prove to be ineffective or poorly tolerated, other agents, such as caffeine and melatonin, can be administered

    Effect of pre-operatory low-level laser therapy on pain, swelling, and trismus associated with third-molar surgery

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    The extraction of impacted third molars is commonly associated to pain, edema, trismus, limited jaw opening and movements. The aim of this retrospective study is to verify if pre-surgical low-level laser therapy (LLLT) associated with the extraction of impacted lower third molars could add benefits to the postoperative symptoms respect LLLT performed only after surgery. Data from 45 patients subjected to a surgical extraction of lower third molars were pooled and divided into three groups. Patients that received only routine management were inserted in the control group. Group 1, were patients that received LLLT immediately after surgery and at 24 hours. In group 2 were included patients treated with LLLT immediately before the extraction and immediately after the end of the procedure. Data were analyzed using linear regression and descriptive statistics. Both laser-treated groups were characterized by minor events of post-surgery complications of pain, edema, trismus. The use of NSAIDs in the first 24 hours was significantly inferior in Group 2. Pre-surgical LLLT treatment seems to increase the analgesic effect of LLLT. However, trismus and edema were reduced in both laser treated groups, independently from the period of irradiation

    Soil Organic Matter and Nutrient Levels in Outdoor Runs in Organic Laying Farms

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    settingsOrder Article Reprints Open AccessArticle Soil Organic Matter and Nutrient Levels in Outdoor Runs in Organic Laying Farms by Michele Zoli 1,*ORCID,Paolo Mantovi 2,Paolo Ferrari 2,Lorenzo Ferrari 1ORCID andValentina Ferrante 1ORCID 1 Department of Environmental Science and Policy, University of Milan, 20133 Milan, Italy 2 Fondazione CRPA Studi Ricerche, 42121 Reggio Emilia, Italy * Author to whom correspondence should be addressed. Animals 2023, 13(3), 401; https://doi.org/10.3390/ani13030401 Received: 28 November 2022 / Revised: 16 January 2023 / Accepted: 19 January 2023 / Published: 25 January 2023 (This article belongs to the Section Animal System and Management) Download Browse Figures Versions Notes Simple Summary Organic egg production is growing more and more, and consumers are increasingly attentive to sustainability issues and animal welfare. In organic production, laying hens must have continuous daytime access to outdoor runs. However, the management of this area is not always easy due to the high load of nutrients due to the feces of the hens. This work, including the FreeBirds project, aims to assess the nutrient load of the free range of three different Italian organic farms in three different contexts. The results show that, in all three farms, there is a high load of nitrates and phosphorus in the areas closest to the hen house, while for other chemical parameters, no clear trend was identified. This study shows that further developments are necessary to make the use of free range more homogeneous to avoid nutrient overloads that could cause high impacts, especially freshwater eutrophication

    Benzo[b]tiophen-3-ol derivatives as effective inhibitors of human monoamine oxidase: design, synthesis, and biological activity

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    A series of benzo[b]thiophen-3-ols were synthesised and investigated as potential human monoamine oxidase (hMAO) inhibitors in vitro as well as ex vivo in rat cortex synaptosomes by means of evaluation of 3,4-dihydroxyphenylacetic acid/dopamine (DOPAC/DA) ratio and lactate dehydrogenase (LDH) activity. Most of these compounds possessed high selectivity for the MAO-B isoform and a discrete antioxidant and chelating potential. Molecular docking studies of all the compounds underscored potential binding site interactions suitable for MAO inhibition activity, and suggested structural requirements to further improve the activity of this scaffold by chemical modification of the aryl substituents. Starting from this heterocyclic nucleus, novel lead compounds for the treatment of neurodegenerative disease could be developed

    Cohort study of electronic cigarette use: effectiveness and safety at 24 months

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    OBJECTIVE: To evaluate the safety and effectiveness of e-cigarettes, by comparing users of only e-cigarettes, smokers of only tobacco cigarettes and dual users. DESIGN: Prospective cohort study. We update previous 12-month findings and report the results of the 24-month follow-up. DATA SOURCES: Direct contact and questionnaires by phone or via internet. METHODS: Adults (30-75 years) were classified as: (1) tobacco smokers, if they smoked ≥1 tobacco cigarette/day, (2) e-cigarette users, if they inhaled ≥50 puffs/week of any type of e-cigarette and (3) dual users, if they smoked tobacco cigarettes and also used e-cigarettes. Carbon monoxide levels were tested in 50% of those declaring tobacco smoking abstinence. Hospital discharge data were used to validate possibly related serious adverse events in 46.0% of the sample. MAIN OUTCOME MEASURES: Sustained abstinence from tobacco cigarettes and/or e-cigarettes after 24 months, the difference in the number of tobacco cigarettes smoked daily between baseline and 24 months, possibly related serious adverse events. RESULTS: Data at 24 months were available for 229 e-cigarette users, 480 tobacco smokers and 223 dual users (overall response rate 68.8%). Of the e-cigarette users, 61.1% remained abstinent from tobacco (while 23.1% and 26.0% of tobacco-only smokers and dual users achieved tobacco abstinence). The rate (18.8%) of stopping use of either product (tobacco and/or e-cigarettes) was not higher for e-cigarette users compared with tobacco smokers or dual users. Self-rated health and adverse events were similar between all groups. Among those continuing to smoke, there were no differences in the proportion of participants reducing tobacco cigarette consumption by 50% or more, the average daily number of cigarettes and the average self-rated health by baseline group. Most dual users at baseline abandoned e-cigarettes and continued to smoke tobacco. Those who continued dual using or converted from tobacco smoking to dual use during follow-up experienced significant improvements in the 3 outcomes compared with those who continued or switched to only smoking tobacco (p<0.001). CONCLUSIONS: E-cigarette use alone might support tobacco quitters remaining abstinent from smoking. However, dual use did not improve the likelihood of quitting tobacco or e-cigarette use, but may be helpful to reduce tobacco consumption. Adverse event data were scarce and must be considered preliminary. TRIAL REGISTRATION NUMBER: NCT01785537
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