67 research outputs found
Identifying the transporters of different flavonoids in plants
We recently identified a new component of flavonoid transport pathways in Arabidopsis. The MATE protein FFT (Flower Flavonoid Transporter) is primarily found in guard cells and seedling roots, and mutation of the transporter results in floral and growth phenotypes. The nature of FFT’s substrate requires further exploration but our data suggest that it is a kaempferol diglucoside. Here we discuss potential partner H+-ATPases and possible redundancy among the close homologues within the large Arabidopsis MATE family
An Arabidopsis rhomboid protease has roles in the chloroplast and in flower development
Increasing numbers of cellular pathways are now recognized to be regulated via proteolytic processing events. The rhomboid family of serine proteases plays a pivotal role in a diverse range of pathways, activating and releasing proteins via regulated intramembrane proteolysis. The prototype rhomboid protease, rhomboid-1 in Drosophila, is the key activator of epidermal growth factor (EGF) receptor pathway signalling in the fly and thus affects multiple aspects of development. The role of the rhomboid family in plants is explored and another developmental phenotype, this time in a mutant of an Arabidopsis chloroplast-localized rhomboid, is reported here. It is confirmed by GFP-protein fusion that this protease is located in the envelope of chloroplasts and of chlorophyll-free plastids elsewhere in the plant. Mutant plants lacking this organellar rhomboid demonstrate reduced fertility, as documented previously with KOM—the one other Arabidopsis rhomboid mutant that has been reported in the literature—along with aberrant floral morphology
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A rapid and low-cost method for genomic DNA extraction from the cyanobacterium Synechocystis
A two-step method is reported for preparation of genomic DNA from the model cyanobacterium Synechocystis that can be performed with minimal equipment and reagents in about an hour. High yields of genetic material can be obtained (200–450 ng/μl) with reasonable purity. A further ethanol precipitation step can be included but is not necessary if template is simply required for PCR or digestion. This new protocol is helpful for amplification of genes of interest in early-stage research projects and for low throughput screening of transformants. It is more reliable than colony PCR of Synechocystis cultures, and less involved and cheaper than existing clean-DNA preparation methods. It represents an unusually simple and reliable extraction protocol for the growing body of research making use of this cyanobacterium
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A day in the life of mitochondria reveals shifting workloads
Mitochondria provide energy for cellular function. We examine daily changing patterns of mitochondrial function and metabolism in Drosophila in vivo in terms of their complex (I-IV) activity, ATP production, glycolysis, and whole fly respiration in the morning, afternoon and night. Complex activity and respiration showed significant and unexpected variation, peaking in the afternoon. However, ATP levels by contrast are >40% greater in the morning and lowest at night when glycolysis peaks. Complex activity modulation was at the protein level with no evidence for differential transcription over the day. Timing differences between increased ATP production and peaks of complex activity may result from more efficient ATP production early in the day leaving complex activity with spare capacity. Optical stimulation of mitochondria is only possible in the mornings when there is such spare capacity.
These results provide first evidence of shifts in cellular energy capacity at the organism level. Understanding their translation may be significant to the chosen timing of energy demanding interventions to improve function and health
Solutions trial: Solution focused brief therapy (SFBT) in 10–17-year-olds presenting at police custody: a randomised controlled trial
Background: Within England, children and young people (CYP) who come into police custody are referred to Liaison and Diversion (L&D) teams. L&D teams have responsibility for liaising with healthcare and other support services while working to divert CYP away from the criminal justice system but have traditionally not provided targeted psychological interventions to CYP. Considering evidence that Solution Focused Brief Therapy (SFBT) leads to a reduction in internalising and externalising behaviour problems in CYP, the aim of this randomised controlled trial (RCT) was to determine whether there is a difference between services as usual (SAU) plus SFBT offered by trained therapists working within a L&D team, and SAU alone, in reducing offending behaviours in 10–17-year-olds presenting at police custody.
Methods: Design: two-arm individually RCT with internal pilot and process evaluation.
Participants: N = approximately 448 CYP aged 10–17 years presenting at one of three police custody suites in the area served by Lancashire and South Cumbria NHS Foundation Trust (LSCFT) who are referred to the L&D team. Participants will be recruited and allocated to intervention:control on a 1:1 basis. Interviews will be performed with 30–40 CYP in the intervention arm, 15 CYP in the control arm, up to 20 parents/guardians across both arms, up to 15 practitioners, and up to 10 site staff responsible for screening CYP for the trial.
Intervention and control: Those allocated to the intervention will be offered SAU plus SFBT, and control participants will receive SAU only.
Primary outcome: CYP frequency of offending behaviours assessed through the Self-Report Delinquency Measure (SRDM) at 12 months post-randomisation.
Secondary outcomes: criminal offence data (national police database); emotional and behavioural difficulties (self-report and parent/guardian reported); gang affiliation (self-report).
Process evaluation: evaluation of acceptability and experiences of the CYP, parents/guardians, site staff and practitioners; fidelity of SFBT delivery.
Discussion: This two-arm individually RCT will evaluate the effectiveness of SFBT in reducing offending behaviours in CYP presenting at police custody suites within the area served by LSCFT. Our process evaluation will assess the fidelity of delivery of SFBT, the factors affecting implementation, the acceptability of SFBT in CYP aged 10–17 years and recruitment and reach. We will also examine systems and structures for future delivery, therefore assessing overall scalability.
Trial registration: ClinicalTrials.gov ISRCTN14195235. Registered on June 16, 2023
A method for visualising fluorescence of flavonoid therapeutics in vivo in the model eukaryote Dictyostelium discoideum
Naturstoff reagent A (diphenylboric acid 2-aminoethyl ester, DPBA) has been used historically in plant science to observe polyphenolic pigments, such as flavonoids, whose fluorescence requires enhancement to be visible by microscopy. Flavonoids are common dietary constituents and are the focus of considerable attention because of their potential as novel therapies for numerous diseases. The molecular basis of therapeutic activity is only gradually being established, and one strand of such research is making use of the social amoeba Dictyostelium discoideum. We extended the application of DPBA to flavonoid imaging in these preclinical studies and report the first method for use of DPBA in this eukaryotic model microbe, and its applicability alongside subcellular markers. This in vivo fluorescence imaging provided a useful adjunct to parallel chemical and genetic studies
An Arabidopsis flavonoid transporter is required for anther dehiscence and pollen development
FLOWER FLAVONOID TRANSPORTER (FFT) encodes a multidrug and toxin efflux family transporter in Arabidopsis thaliana. FFT (AtDTX35) is highly transcribed in floral tissues, the transcript being localized to epidermal guard cells, including those of the anthers, stigma, siliques and nectaries. Mutant analysis demonstrates that the absence of FFT transcript affects flavonoid levels in the plant and that the altered flavonoid metabolism has wide-ranging consequences. Root growth, seed development and germination, and pollen development, release and viability are all affected. Spectrometry of mutant versus wild-type flowers shows altered levels of a glycosylated flavonol whereas anthocyanin seems unlikely to be the substrate as previously speculated. Thus, as well as adding FFT to the incompletely described flavonoid transport network, it is found that correct reproductive development in Arabidopsis is perturbed when this particular transporter is missing
Solutions Trial: Solution Focused Brief Therapy (SFBT) in 10–17-year-olds presenting at police custody: a randomised controlled trial
Background: Within England, children and young people (CYP) who come into police custody are referred to Liaison and Diversion (L&D) teams. L&D teams have responsibility for liaising with healthcare and other support services while working to divert CYP away from the criminal justice system but have traditionally not provided targeted psychological interventions to CYP. Considering evidence that Solution Focused Brief Therapy (SFBT) leads to a reduction in internalising and externalising behaviour problems in CYP, the aim of this randomised controlled trial (RCT) was to determine whether there is a difference between services as usual (SAU) plus SFBT offered by trained therapists working within a L&D team, and SAU alone, in reducing offending behaviours in 10–17-year-olds presenting at police custody. Methods: Design: two-arm individually RCT with internal pilot and process evaluation. Participants: N = approximately 448 CYP aged 10–17 years presenting at one of three police custody suites in the area served by Lancashire and South Cumbria NHS Foundation Trust (LSCFT) who are referred to the L&D team. Participants will be recruited and allocated to intervention:control on a 1:1 basis. Interviews will be performed with 30–40 CYP in the intervention arm, 15 CYP in the control arm, up to 20 parents/guardians across both arms, up to 15 practitioners, and up to 10 site staff responsible for screening CYP for the trial. Intervention and control: Those allocated to the intervention will be offered SAU plus SFBT, and control participants will receive SAU only. Primary outcome: CYP frequency of offending behaviours assessed through the Self-Report Delinquency Measure (SRDM) at 12 months post-randomisation. Secondary outcomes: criminal offence data (national police database); emotional and behavioural difficulties (self-report and parent/guardian reported); gang affiliation (self-report). Process evaluation: evaluation of acceptability and experiences of the CYP, parents/guardians, site staff and practitioners; fidelity of SFBT delivery. Discussion: This two-arm individually RCT will evaluate the effectiveness of SFBT in reducing offending behaviours in CYP presenting at police custody suites within the area served by LSCFT. Our process evaluation will assess the fidelity of delivery of SFBT, the factors affecting implementation, the acceptability of SFBT in CYP aged 10–17 years and recruitment and reach. We will also examine systems and structures for future delivery, therefore assessing overall scalability. Trial registration: ClinicalTrials.gov ISRCTN14195235. Registered on June 16, 2023
BRCA2 polymorphic stop codon K3326X and the risk of breast, prostate, and ovarian cancers
Background: The K3326X variant in BRCA2 (BRCA2*c.9976A>T; p.Lys3326*; rs11571833) has been found to be associated with small increased risks of breast cancer. However, it is not clear to what extent linkage disequilibrium with fully pathogenic mutations might account for this association. There is scant information about the effect of K3326X in other hormone-related cancers.
Methods: Using weighted logistic regression, we analyzed data from the large iCOGS study including 76 637 cancer case patients and 83 796 control patients to estimate odds ratios (ORw) and 95% confidence intervals (CIs) for K3326X variant carriers in relation to breast, ovarian, and prostate cancer risks, with weights defined as probability of not having a pathogenic BRCA2 variant. Using Cox proportional hazards modeling, we also examined the associations of K3326X with breast and ovarian cancer risks among 7183 BRCA1 variant carriers. All statistical tests were two-sided.
Results: The K3326X variant was associated with breast (ORw = 1.28, 95% CI = 1.17 to 1.40, P = 5.9x10- 6) and invasive ovarian cancer (ORw = 1.26, 95% CI = 1.10 to 1.43, P = 3.8x10-3). These associations were stronger for serous ovarian cancer and for estrogen receptor–negative breast cancer (ORw = 1.46, 95% CI = 1.2 to 1.70, P = 3.4x10-5 and ORw = 1.50, 95% CI = 1.28 to 1.76, P = 4.1x10-5, respectively). For BRCA1 mutation carriers, there was a statistically significant inverse association of the K3326X variant with risk of ovarian cancer (HR = 0.43, 95% CI = 0.22 to 0.84, P = .013) but no association with breast cancer. No association with prostate cancer was observed.
Conclusions: Our study provides evidence that the K3326X variant is associated with risk of developing breast and ovarian cancers independent of other pathogenic variants in BRCA2. Further studies are needed to determine the biological mechanism of action responsible for these associations
Evaluating Mitigation Effort: Tools and Institutions for Assessing Nationally Determined Contributions
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