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Flowering plants exhibit a wide range of sexual reproduction systems, with the majority being hermaphroditic. However, some plants, such as Actinidia arguta (kiwiberry), have evolved into dioecious species with distinct female and male vines. In this study, we investigated the flower load and growth habits of female kiwiberry genotypes to identify the genetic basis of high yield with low maintenance requirements. Owing to the different selection approaches between female and male genotypes, we further extended our study to male kiwiberry genotypes. By combining both investigations, we present a novel breeding tool for dioecious crops. A population of A. arguta seedlings was phenotyped for flower load traits, in particular the proportion of non-floral shoots, proportion of floral shoots, and average number of flowers per floral shoot. Quantitative trait locus (QTL) mapping was used to analyse the genetic basis of these traits. We identified putative QTLs on chromosome 3 associated with flower-load traits. A pleiotropic effect of the male-specific region of the Y chromosome (MSY) on chromosome 3 affecting flower load-related traits between female and male vines was observed in an A. arguta breeding population. Furthermore, we utilized Genomic Best Linear Unbiased Prediction (GBLUP) to predict breeding values for the quantitative traits by leveraging genomic data. This approach allowed us to identify and select superior genotypes. Our findings contribute to the understanding of flowering and fruiting dynamics in Actinidia species, providing insights for kiwiberry breeding programs aiming to improve yield through the utilization of genomic methods and trait mapping. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01476-7.
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In dioecious crops such as Actinidia arguta (kiwiberries), some of the main challenges when breeding for fruit characteristics are the selection of potential male parents and the long juvenile period. Currently, breeding values of male parents are estimated through progeny tests, which makes the breeding of new kiwiberry cultivars time-consuming and costly. The application of best linear unbiased prediction (BLUP) would allow direct estimation of sex-related traits and speed up kiwiberry breeding. In this study, we used a linear mixed model approach to estimate narrow sense heritability for one vine-related trait and five fruit-related traits for two incomplete factorial crossing designs. We obtained BLUPs for all genotypes, taking into consideration whether the relationship was pedigree-based or marker-based. Owing to the high cost of genome sequencing, it is important to understand the effects of different sources of relationship matrices on estimating breeding values across a breeding population. Because of the increasing implementation of genomic selection in crop breeding, we compared the effects of incorporating different sources of information in building relationship matrices and ploidy levels on the accuracy of BLUPs' heritability and predictive ability. As kiwiberries are autotetraploids, multivalent chromosome formation and occasionally double reduction can occur during meiosis, and this can affect the accuracy of prediction. This study innovates the breeding programme of autotetraploid kiwiberries. We demonstrate that the accuracy of BLUPs of male siblings, without phenotypic observations, strongly improved when a tetraploid marker-based relationship matrix was used rather than parental BLUPs and female siblings with phenotypic observations. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01419-8.
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Environmental extremes, such as drought and flooding, are becoming more common with global warming, resulting in significant crop losses. Understanding the mechanisms underlying the plant water stress response, regulated by the abscisic acid (ABA) pathway, is crucial to building resilience to climate change. Potted kiwifruit plants (two cultivars) were exposed to contrasting watering regimes (water logging and no water). Root and leaf tissues were sampled during the experiments to measure phytohormone levels and expression of ABA pathway genes. ABA increased significantly under drought conditions compared with the control and waterlogged plants. ABA-related gene responses were significantly greater in roots than leaves. ABA responsive genes, DREB2 and WRKY40, showed the greatest upregulation in roots with flooding, and the ABA biosynthesis gene, NCED3, with drought. Two ABA-catabolic genes, CYP707A i and ii were able to differentiate the water stress responses, with upregulation in flooding and downregulation in drought. This study has identified molecular markers and shown that water stress extremes induced strong phytohormone/ABA gene responses in the roots, which are the key site of water stress perception, supporting the theory kiwifruit plants regulate ABA to combat water stress.
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Ácido Abscísico , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/metabolismo , Desidratação/metabolismo , Secas , Estresse Fisiológico/genética , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Folhas de Planta/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de PlantasRESUMO
The symbiotic Epichloë festucae var. lolii endophyte produces alkaloids which can provide its host grass, perennial ryegrass (Lolium perenne L), with a selective advantage in both natural and agricultural managed ecosystems. This study focuses on understanding the alkaloid concentrations that occur in endophyte-infected perennial ryegrass during the early establishment phase. In a glasshouse experiment fungal alkaloid concentrations (peramine, lolitrem B, ergovaline, and epoxy-janthitrems) were measured in perennial ryegrass seedlings infected with E. festucae var. lolii proprietary strains AR1, AR37, NEA2, and NZ common toxic for 69 days after sowing. The endophyte becomes metabolically active, starting alkaloid production, as early as 6 days after sowing. Alkaloid concentrations peaked in 8- to 10- day-old seedlings due to a seedling growth slowdown. This study provides data showing that the loss of insect protection in endophyte-infected seedlings is linked to a reduction in chemical defence after seed-stored, maternally synthesised alkaloids are diluted by seedling dry matter accumulation.
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Alcaloides/metabolismo , Endófitos/metabolismo , Epichloe/metabolismo , Lolium/crescimento & desenvolvimento , Lolium/microbiologia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , SimbioseRESUMO
The original version of this article unfortunately contained a mistake. There is a mistake in the affiliation section and Figure 6. The correct affiliation and Figure 6 are shown here.
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In ascomycetes and basidiomycetes, iron-responsive GATA-type transcriptional repressors are involved in regulating iron homeostasis, notably to prevent iron toxicity through control of iron uptake. To date, it has been unknown whether this iron regulator contributes toward mutualistic endosymbiosis of microbes with plants, a system where the endophyte must function within the constraints of an in-host existence, including a dependency on the host for nutrient acquisition. Functional characterization of one such protein, SreA from Epichloë festucae, a fungal endosymbiont of cool-season grasses, indicates that regulation of iron homeostasis processes is important for symbiotic maintenance. The deletion of the sreA gene (ΔsreA) led to iron-dependent aberrant hyphal growth and the gradual loss of endophyte hyphae from perennial ryegrass. SreA negatively regulates the siderophore biosynthesis and high-affinity iron uptake systems of E. festucae, similar to other fungi, resulting in iron accumulation in mutants. Our evidence suggests that SreA is involved in the processes that moderate Epichloë iron acquisition from the plant apoplast, because overharvesting of iron in ΔsreA mutants was detected as premature chlorosis of the host using a hydroponic plant growth assay. E. festucae appears to have a tightly regulated iron management system, involving SreA that balances endophyte growth with its survival and prevents overcompetition with the host for iron in the intercellular niche, thus promoting mutualistic associations. Mutations that interfere with Epichloë iron management negatively affect iron-dependent fungal growth and destabilize mutualistic Epichloë -ryegrass associations.
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Epichloe , Fatores de Transcrição GATA , Lolium , Simbiose , Epichloe/genética , Proteínas Fúngicas/genética , Fatores de Transcrição GATA/genética , Fatores de Transcrição GATA/metabolismo , Ferro/metabolismo , Lolium/microbiologia , Mutação , Simbiose/genéticaRESUMO
A crucial step in the infection process of grazing ruminants by gastro-intestinal nematodes is the exsheathment of the infective third-stage larva following ingestion. Recently, heat shock was shown to play an important role in the carbon dioxide (CO2)-dependent exsheathment response in Haemonchus contortus. The current in vitro study set out to evaluate the role of heat shock in other abomasal species. In rumen fluid, all species tested exsheathed rapidly and efficiently in response to heat shock and CO2. This response was significantly higher compared to slow temperature changes, supporting the hypothesis that heat shock plays an important role in vivo. However, in artificial buffer, the effect of heat shock was species-dependent. For H. contortus and Ostertagia leptospicularis, the response in artificial buffer was similar to rumen fluid. In contrast, Ostertagia ostertagi and Teladorsagia circumcincta exsheathment was significantly lower and/or slower in artificial buffer, and there was no benefit of heat shock. For these two species, it appears that there are co-factors in the rumen fluid, in addition to heat shock and CO2, contributing to exsheathment. Overall, the data indicate that there are significant differences between abomasal species in their response to exsheathment triggers.
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Abomaso/parasitologia , Dióxido de Carbono/farmacologia , Haemonchus/fisiologia , Resposta ao Choque Térmico/fisiologia , Ostertagia/fisiologia , Trichostrongyloidea/fisiologia , Animais , Trato Gastrointestinal/parasitologia , Larva/fisiologia , Rúmen/parasitologia , Ruminantes/parasitologiaRESUMO
The first step in the infection process of grazing ruminants by gastrointestinal nematodes is the exsheathment of the third-stage larva (L3). Exsheathment of various species can be achieved in vitro using carbon dioxide (CO2) under the appropriate temperature and pH conditions. However, it remains unclear whether elevated CO2 levels are an absolute requirement for exsheathment. Exsheathment of four abomasal species was investigated in both the presence and absence of CO2, in either rumen fluid (cow or sheep) or buffer (standard or enriched). Exsheathment of Ostertagia ostertagi, Teladorsagia circumcincta and Ostertagia leptospicularis was observed in CO2-depleted rumen fluid and enriched buffer (respectively 46%, 22% and 15% in rumen fluid and 28% 18% and 26% in enriched buffer after 24 h). The level of this response was dependent on the species as well as the medium, and exsheathment was significantly higher in the presence of CO2. For Haemonchus contortus, exsheathment could only be achieved under CO2-saturated conditions. In conclusion, even though these parasite species exsheath in the same environment, there were significant differences in the minimal requirements to trigger their exsheathment. Some abomasal species were capable of exsheathment in the absence of CO2, which is likely facilitated by cofactors present in the rumen fluid and/or enriched buffer.
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Dióxido de Carbono/metabolismo , Ostertagia/crescimento & desenvolvimento , Ostertagia/metabolismo , Trichostrongyloidea/crescimento & desenvolvimento , Trichostrongyloidea/metabolismo , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Haemonchus/fisiologia , Larva , Rúmen/química , Rúmen/parasitologia , Ovinos , Doenças dos Ovinos/parasitologia , TemperaturaRESUMO
Gastrointestinal parasites are an important health issue in grazing ruminants. Understanding the processes involved in the transition from the free living to the parasitic life stage of these nematodes is one avenue to identifying new targets amenable to future intervention. The transition to parasitism is initiated by exsheathment and is triggered by the sudden change in environment after ingestion of the infective larva by the host. Two major changes in environment are the increases in temperature and carbon dioxide (CO2) levels. For CO2 a role in exsheathment has been described previously, but the exact role of temperature was unclear. The current study is the first to investigate the importance of temperature in triggering exsheathment of Haemonchus contortus. Carbon dioxide induced exsheathment in H. contortus proved to be temperature dependent, as no exsheathment was observed at room temperatures. However, the temperature requirement to trigger exsheathment was quite specific. A rapid change in temperature (heat shock) very efficiently induced high levels of exsheathment. In contrast, when the larvae were exposed to a slow increase in temperature, the exsheathment response was smaller and delayed. Further investigation revealed that timing of the heat shock in relation to the CO2 administration was crucial, as well as the final temperature and magnitude of the heat shock. In conclusion, these data indicate that heat shock rather than temperature itself is a crucial aspect in triggering the biological exsheathment cascade, and thus infection process, of H. contortus.
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Haemonchus/fisiologia , Larva/crescimento & desenvolvimento , Animais , Dióxido de Carbono/metabolismo , Ecossistema , Meio Ambiente , Feminino , Haemonchus/crescimento & desenvolvimento , Temperatura Alta , Larva/metabolismo , MasculinoRESUMO
Sharpea and Kandleria are associated with rumen samples from low-methane-emitting sheep. Four strains of each genus were studied in culture, and the genomes of nine strains were analysed, to understand the physiology of these bacteria. All eight cultures grew equally well with d-glucose, d-fructose, d-galactose, cellobiose, and sucrose supplementation. d-Lactate was the major end product, with small amounts of the mixed acid fermentation products formate, acetate and ethanol. Genes encoding the enzymes necessary for this fermentation pattern were found in the genomes of four strains of Sharpea and five of Kandleria. Strains of Sharpea produced traces of hydrogen gas in pure culture, but strains of Kandleria did not. This was consistent with finding that Sharpea, but not Kandleria, genomes contained genes coding for hydrogenases. It was speculated that, in co-culture with a methanogen, Sharpea and Kandleria might change their fermentation pattern from a predominately homolactic to a predominately mixed acid fermentation, which would result in a decrease in lactate production and an increase in formation of acetate and perhaps ethanol. However, Sharpea and Kandleria did not change their fermentation products when co-cultured with Methanobrevibacter olleyae, a methanogen that can use both hydrogen and formate, and lactate remained the major end product. The results of this study therefore support a hypothesis that explains the link between lower methane yields and larger populations of Sharpea and Kandleria in the rumens of sheep.
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Firmicutes/metabolismo , Ácido Láctico/metabolismo , Lactobacillales/metabolismo , Metano/metabolismo , Methanobrevibacter/crescimento & desenvolvimento , Rúmen/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Cocultura , Fermentação , Firmicutes/genética , Firmicutes/crescimento & desenvolvimento , Firmicutes/isolamento & purificação , Hidrogênio/metabolismo , Hidrogenase/genética , Hidrogenase/metabolismo , Lactobacillales/genética , Lactobacillales/crescimento & desenvolvimento , Lactobacillales/isolamento & purificação , Methanobrevibacter/metabolismo , OvinosRESUMO
Altered gastric accommodation and intestinal morphology suggest impaired gastrointestinal (GI) transit may occur in the Wistar-Kyoto (WKY) rat strain, as common in stress-associated functional GI disorders. Because changes in GI transit can alter microbiota composition, we investigated whether these are altered in WKY rats compared with the resilient Sprague-Dawley (SD) rats under basal conditions and characterized plasma lipid and metabolite differences. Bead transit was tracked by X-ray imaging to monitor gastric emptying (4 h), small intestine (SI) transit (9 h), and large intestine transit (12 h). Plasma extracts were analyzed by lipid and hydrophilic interaction liquid chromatography (HILIC) and liquid chromatography-mass spectrometry (LC-MS). Cecal microbial composition was determined by Illumina MiSeq 16S rRNA amplicon sequencing and analysis using the QIIME pipeline. Stomach retention of beads was 77% for WKY compared with 35% for SD rats. GI transit was decreased by 34% (9 h) and 21% (12 h) in WKY compared with SD rats. Excluding stomach retention, transiting beads moved 29% further along the SI over 4-9 h for WKY compared with SD rats. Cecal Ruminococcus, Roseburia, and unclassified Lachnospiraceae genera were less abundant in WKY rats, whereas the minor taxa Dorea, Turicibacter, and Lactobacillus were higher. Diglycerides, triglycerides, phosphatidyl-ethanolamines, and phosphatidylserine were lower in WKY rats, whereas cholesterol esters and taurocholic acids were higher. The unexpected WKY rat phenotype of delayed gastric emptying, yet rapid SI transit, was associated with altered lipid and metabolite profiles. The delayed gastric emptying of the WKY phenotype suggests this rat strain may be useful as a model for gastroparesis.NEW & NOTEWORTHY This study reveals that the stress-prone Wistar-Kyoto rat strain has a baseline physiology of gastroparesis and rapid small intestine transit, together with metabolic changes consistent with lipid metabolism-associated dysbiosis, compared with nonstress-prone rats. This suggests that the Wistar-Kyoto rat strain may be an appropriate animal model for gastroparesis.
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Trato Gastrointestinal/fisiologia , Trânsito Gastrointestinal/fisiologia , Gastroparesia , Metabolismo dos Lipídeos , Animais , Peso Corporal , Cromatografia Líquida/métodos , Corticosterona/sangue , Modelos Animais de Doenças , Esvaziamento Gástrico/fisiologia , Trato Gastrointestinal/microbiologia , Masculino , Espectrometria de Massas , Metabolômica , Ratos , Ratos Endogâmicos WKY , Ratos Sprague-DawleyRESUMO
Optogenetics and photopharmacology enable the spatio-temporal control of cell and animal behavior by light. Although red light offers deep-tissue penetration and minimal phototoxicity, very few red-light-sensitive optogenetic methods are currently available. We have now developed a red-light-induced homodimerization domain. We first showed that an optimized sensory domain of the cyanobacterial phytochromeâ 1 can be expressed robustly and without cytotoxicity in human cells. We then applied this domain to induce the dimerization of two receptor tyrosine kinases-the fibroblast growth factor receptorâ 1 and the neurotrophin receptor trkB. This new optogenetic method was then used to activate the MAPK/ERK pathway non-invasively in mammalian tissue and in multicolor cell-signaling experiments. The light-controlled dimerizer and red-light-activated receptor tyrosine kinases will prove useful to regulate a variety of cellular processes with light.
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Nature has incorporated small photochromic molecules, colloquially termed 'photoswitches', in photoreceptor proteins to sense optical cues in phototaxis and vision. While Nature's ability to employ light-responsive functionalities has long been recognized, it was not until recently that scientists designed, synthesized and applied synthetic photochromes to manipulate many of which open rapidly and locally in their native cell types, biological processes with the temporal and spatial resolution of light. Ion channels in particular have come to the forefront of proteins that can be put under the designer control of synthetic photochromes. Photochromic ion channel controllers are comprised of three classes, photochromic soluble ligands (PCLs), photochromic tethered ligands (PTLs) and photochromic crosslinkers (PXs), and in each class ion channel functionality is controlled through reversible changes in photochrome structure. By acting as light-dependent ion channel agonists, antagonist or modulators, photochromic controllers effectively converted a wide range of ion channels, including voltage-gated ion channels, 'leak channels', tri-, tetra- and pentameric ligand-gated ion channels, and temperature-sensitive ion channels, into man-made photoreceptors. Control by photochromes can be reversible, unlike in the case of 'caged' compounds, and non-invasive with high spatial precision, unlike pharmacology and electrical manipulation. Here, we introduce design principles of emerging photochromic molecules that act on ion channels and discuss the impact that these molecules are beginning to have on ion channel biophysics and neuronal physiology.
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Ativação do Canal Iônico/efeitos da radiação , Canais Iônicos/efeitos da radiação , Luz , Optogenética , Animais , Sítios de Ligação , Humanos , Canais Iônicos/química , Canais Iônicos/genética , Canais Iônicos/metabolismo , Ligantes , Potenciais da Membrana , Estimulação Luminosa , Ligação Proteica , Conformação Proteica , Relação Estrutura-AtividadeRESUMO
OBJECTIVES: To determine long-term adherence to a 5 day antibiotic course guideline for treating intensive care unit (ICU)-acquired Gram-negative bacteria (GNB) infections. METHODS: Descriptive analysis of patient-level data on all GNB-active antibiotics prescribed from day 3 and all GNB identified in clinical samples in 5350 patients admitted to a 30 bed general ICU between 2002 and 2009. RESULTS: Four thousand five hundred and eleven of 5350 (84%) patients were treated with one or more antibiotics active against GNB commenced from day 3. Gentamicin was the most frequently prescribed antibiotic (92.2 days of therapy/1000 patient-days). Only 6% of courses spanned >6 days of therapy and 89% of antibiotic therapy days were with a single antibiotic active against GNB. There was no significant difference between gentamicin and meropenem in the number of first courses in which a resistant GNB was identified in blood cultures [11/1177 (0.9%) versus 5/351 (1.4%); Pâ=â0.43] or respiratory tract specimens [59/951 (6.2%) versus 17/246 (6.9%); Pâ=â0.68] at the time of starting therapy. CONCLUSIONS: This study demonstrates long-term adherence to a 5 day course antibiotic guideline for treatment of ICU-associated GNB infections. This guideline is a potential antibiotic-sparing alternative to currently recommended dual empirical courses extending to ≥7 days.
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Antibacterianos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Unidades de Terapia Intensiva , Idoso , Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Quimioterapia Combinada , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND/AIMS: Citrate is an effective anticoagulant during continuous renal replacement therapy (CRRT). Previous studies showed raised parathyroid hormone (PTH) levels when aiming for serum ionized calcium [Cai] between 0.8 and 1.1 mmol/l. Our objective was to assess whether citrate-based CRRT with physiologic target systemic [Ca(i)] between 1.12 and 1.20 mmol/l could maintain stable PTH levels. METHODS: Measurement of intact PTH (PTHi) in 30 consecutive critically ill patients treated with citrate-based CRRT. RESULTS: Thirty patients [mean age: 70.4 (SD 11.3) years; 56.7% males] were enrolled. Mean serum [Ca(i)] was 1.16 mmol/l (SD 0.09), 1.13 mmol/l (SD 0.09), 1.17 mmol/l (SD 0.05) and 1.16 mmol/l (SD 0.04) at baseline, 12, 24 and 48 h, respectively (p = 0.29). Median PTHi levels (interquartile range) at baseline, 12, 24 and 48 h were 66.5 (43-111), 109 (59.5-151.5), 88.5 (47-133) and 85 pg/ml (53-140), respectively. The differences between baseline and 12 h and across all time points were statistically not significant (p = 0.16 and p = 0.49, respectively). In a mixed-effects model, each 0.1 mmol/l increase in serum [Ca(i)] was associated with a 31.2% decrease in PTHi (p < 0.001). Results were unchanged after adjustment for age, gender, magnesium, phosphate, arterial pH and time spent on CRRT. CONCLUSIONS: Maintaining systemic [Ca(i)] within the physiologic range was associated with stable PTHi levels.
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Cálcio/sangue , Ácido Cítrico/uso terapêutico , Hormônio Paratireóideo/sangue , Terapia de Substituição Renal/efeitos adversos , Terapia de Substituição Renal/métodos , Trombose/etiologia , Trombose/prevenção & controle , Idoso , Anticoagulantes/uso terapêutico , Feminino , Humanos , Íons , Falência Renal Crônica/metabolismo , Falência Renal Crônica/terapia , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: Micronutrients, principally vitamins and minerals, play an important role both in health and in disease. Parenteral micronutrient products are commonly prescribed for critically ill patients both in line with the terms of the product's license, and for other indications where there is an underpinning physiological rationale, or precedent, for their use but little evidence. This survey sought to understand United Kingdom (UK) prescribing practice in this area. METHODS: A 12-question survey was circulated to healthcare professionals working in UK critical care units. The survey was designed to explore several aspects of micronutrient prescribing or recommendation practice by the critical care multidisciplinary team, including indications and underpinning clinical rationale for using these products, dosing, and considerations with respect to micronutrients delivered as part of nutrition. Results were analysed, exploring indications, considerations relating to diagnoses, therapies including renal replacement therapies, and method of nutrition. RESULTS: 217 responses were included in the analysis, with 58% from physicians and the remaining 42% from nurses, pharmacists, dietitians and other healthcare disciplines. Vitamins were most commonly prescribed or recommended for Wernicke's encephalopathy (prescribed or recommended by 76% of respondents), treatment of refeeding syndrome (64.5%), and for patients with unknown or uncertain alcohol intake history (63.6%). These clinically suspected or confirmed indications were cited more frequently as a reason to prescribe than laboratory identified deficiency states. 20% of respondents indicated that they would prescribe or recommend parenteral vitamins for patients requiring renal replacement therapy. The practice of vitamin C prescribing was heterogeneous, including dose and indication. Trace elements were prescribed or recommended less often than vitamins, with the most frequently reported indications being for patients requiring parenteral nutrition (42.9%), biochemically confirmed deficiency states (35.9%), and for treatment of refeeding syndrome (26.3%). CONCLUSIONS: Micronutrient prescribing in ICUs in the UK is heterogeneous, with clinical scenarios where there is an evidence base or an established precedent for their use often guiding decisions to use micronutrient products. Further work to examine the potential benefits and harms on patient-oriented outcomes of micronutrient product administration should be undertaken, to facilitate their judicious and cost-effective use, with a focus on areas where they have a theoretical benefit.
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Síndrome da Realimentação , Oligoelementos , Humanos , Micronutrientes , Vitaminas , Vitamina A , Vitamina K , Cuidados Críticos/métodosRESUMO
Increasing water-soluble carbohydrate (WSC) content in white clover is important for improving nutritional quality and reducing environmental impacts from pastoral agriculture. Elucidation of genes responsible for foliar WSC variation would enhance genetic improvement by enabling molecular breeding approaches. The aim of the present study was to identify single nucleotide polymorphisms (SNPs) associated with variation in foliar WSC in white clover. A set of 935 white clover individuals, randomly sampled from five breeding pools selectively bred for divergent (low or high) WSC content, were assessed with 14,743 genotyping-by-sequencing SNPs, using three outlier detection methods: PCAdapt, BayeScan and KGD-FST. These analyses identified 33 SNPs as discriminating between high and low WSC populations and putatively under selection. One SNP was located in the intron of ERD6-like 4, a gene coding for a sugar transporter located on the vacuole membrane. A genome-wide association study using a subset of 605 white clover individuals and 5,757 SNPs, identified a further 12 SNPs, one of which was associated with a starch biosynthesis gene, glucose-1-phosphate adenylyltransferase, glgC. Our results provide insight into genomic regions underlying WSC accumulation in white clover, identify candidate genomic regions for further functional validation studies, and reveal valuable information for marker-assisted or genomic selection in white clover.
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INTRODUCTION: Delirium affects up to 80% of patients admitted to intensive care units (ICUs) and contributes to increased morbidity and mortality. Haloperidol is the gold standard for treatment, although quetiapine has been successfully used in the management of delirium. METHODS: We conducted a retrospective study of patients admitted to the ICU between February 2008 and May 2010 who were prescribed quetiapine by the attending clinician. Data collected included demographics, history of drug and/or alcohol dependence, ICU and hospital length of stay, length of mechanical ventilation and the duration of treatment with sedatives and medications for delirium. The daily dose of quetiapine was recorded. Hyperactive or mixed delirium was identified by a validated chart review and a Richmond Agitation Sedation Scale (RASS) score persistently greater than 1 for 48 hours despite therapy. RESULTS: Seventeen patients were included. Delirium onset occurred after a median of five days. Patients were being given at least four agents for delirium prior to the introduction of quetiapine, and they had a median RASS score of 3. Quetiapine was initiated at a 25 mg daily dose and titrated to a median daily dose of 50 mg. The median duration of delirium prior to quetiapine therapy was 15 days. Quetiapine commencement was associated with a reduction in the need for other medications (within 0 to 6 days) and resolution of delirium within a median of four days. Adverse events included somnolence and transient hypotension. CONCLUSIONS: This case series provides an initial effort to explore a possible role for quetiapine in the management of refractory hyperactive and mixed ICU delirium.
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Delírio/tratamento farmacológico , Dibenzotiazepinas/uso terapêutico , Unidades de Terapia Intensiva , Agitação Psicomotora/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Delírio/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agitação Psicomotora/epidemiologia , Fumarato de Quetiapina , Estudos RetrospectivosRESUMO
Epichloë endophytes are filamentous fungi (family Clavicipitaceae) that live in symbiotic associations with grasses in the sub family Poöideae. In New Zealand, E. festucae var. lolii confers significant resistance to perennial ryegrass (Lolium perenne) against insect and animal herbivory and is an essential component of pastoral agriculture, where ryegrass is a major forage species. The fungus produces in planta a range of bioactive secondary metabolites, including ergovaline, which has demonstrated bioactivity against the important pasture pest black beetle, but can also cause mammalian toxicosis. We genetically modified E. festucae var. lolii strain AR5 to eliminate key enzymatic steps in the ergovaline pathway to determine if intermediate ergot alkaloid compounds can still provide insecticidal benefits in the absence of the toxic end product ergovaline. Four genes (dmaW, easG, cloA, and lpsB) spanning the pathway were deleted and each deletion mutant was inoculated into five different plant genotypes of perennial ryegrass, which were later harvested for a full chemical analysis of the ergot alkaloid compounds produced. These associations were also used in a black beetle feeding deterrence study. Deterrence was seen with just chanoclavine present, but was cumulative as more intermediate compounds in the pathway were made available. Ergovaline was not detected in any of the deletion associations, indicating that bioactivity towards black beetle can be obtained in the absence of this mammalian toxin.