1,409 research outputs found
Nematoxic effect of essential oils and their fractions against the pinewood nematode, Bursaphelenchus xylophilus
The pinewood nematode (PWN) Bursaphelenchus xylophilus is a highly pathogenic
plant parasite that greatly affects pine forests. In Portugal, the most affected species is
Pinus pinaster Aiton. Despite great efforts, since its fist detection in 1999, the PWN has
spread through the country, including Madeira Island, having been recently detected in
Spain [1,2]. Containing this pest is of the utmost importance for European pine forest
safeguard.
Since most synthetic chemicals used to control phytoparasites are toxic to humans and
animals, and can accumulate in the soil and in food plants [3], in the present work, the
nematoxic potential of over 80 essential oils (EOs), isolated from the Portuguese flora,
were assessed against the PWN. EOs were isolated by hydrodistillation and analysed by
GC and GC-MS [3]. EOs hydrocarbon and oxygen-containing fractions were obtained as
in [4]. Direct-contact assays, adapted from [3], were performed by adding EOs/methanol
stock-solutions to 50-100 mixed-stage PWN suspensions. After 24h in darkness, dead
and live nematodes were counted under an inverted microscope. Assays were repeated
at least 10 times in two series.
Mortalities â„96% were obtained with 2ÎŒL/mL of the EOs isolated from Cymbopogon
citratus, Eucalyptus citriodora, Mentha arvensis, Origanum virens, Origanum vulgare,
Ruta graveolens, Satureja montana, Syzygium aromaticum, Thymbra capitata, Thymus
caespititius (carvacrol and/or thymol-rich), Thymus vulgaris and Thymus zygis. These
EOs were further tested at 1, 0.5 and 0.25ÎŒL/mL. Minimum lethal concentrations (LC100)
<0.4ÎŒL/mL, were obtained for the 2-undecanone-rich R. graveolens EO and the carvacrol
and Îł-terpinene-rich S. montana and T. capitata EOs. Assays with EO fractions revealed
that the monoterpene-rich nematoxic EOs control PWN through their combined
hydrocarbon and oxygen-containing fractions through additive and/or synergic relations.
As complex mixtures of active components, EOs may prove to be effective nematoxic
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Development of prostrate cancer vaccine using PAP as target antigen
Treatment options for patients with advanced prostate cancer (PC) still remain limited and rarely curative. The prostatic acid phosphatase (PAP) is prostate specific protein over-expressed in more than 90% of prostate tumours. Although an FDA-approved vaccine for the treatment of advanced prostate disease, PROVENGEÂź (sipuleucel-T), has been shown to prolong survival, the precise sequence of the PAP protein responsible for the outcome remains unknown. As the PAP antigen is one of the very few prostate-specific antigens for which there is a rodent equivalent with high homology, pre-clinical studies using PAP have the potential to be directly relevant to the clinical setting. The current study identified HLA-A2 and HLA-DR1 PAP-derived peptides using the transgenic HHDII/DR1 and C57Bl/6 mice. The PAP-114-128 (15-mer) peptide was shown to elicit CD4+ and CD8+ T-cell-specific responses in C57Bl/6 mice. Furthermore, when immunised in a DNA vector format (ImmunoBody), PAP-114-128 was able to prevent and reduce the growth of TRAMP C1 prostate cancer cell-derived tumours in both prophylactic and therapeutic settings
Isolation and characterization of Rep PepYLCV encoding gene from West Sumatra
Replicase (Rep) protein of Geminivirus is known as one of the important components not only for its successful replication in their host but also known to interact with various host plant proteins. However, it is still unclear if those interactions are associated with symptoms level. This research aims to explore the possibility of Rep as pathogenic determinant by in silico approach. Here we report the comparison of three Rep sequences isolated from Pesisir Selatan and Tanah Datar districts in West Sumatra Indonesia. The PCR-based cloning approach was used in this study to isolate the gene sequences from all isolates. Pathogenic determinant was predicted from phenotype and genotype analysis. Phenotype data showed symptoms appearance after 8 dpi for PSSWS14 and 20 dpi for PSSWS3. Furthermore, genotype showed that the nonconserved region in N-terminal of Rep makes different in its putative binding site. It is prospective to be related to the symptoms appearance rates. We predict the differences in N-terminal of Rep affecting the symptoms appearance rates of Geminivirus infection
Optimising medication use for people living with dementia and their caregivers
Background: As people living with dementia (PLWD) gradually lose their ability to manage their medicines appropriately, family members or friends step in to assist them. A variety of medication and person-related factors affect the medication use process. Aim: To identify and examine the factors contributing to the challenges to medication use from the perspective of PLWD and from their caregivers in the community and care home setting, in order to help maintain optimal therapy for this patient population, with a focus on the use of appropriate drug formulations, along dementia progression. In addition, to make recommendations for assistance for PLWD and caregivers to help alleviate caregiver burden and optimise the medication use process. Methods: To enable a comprehensive examination of issues from perspectives of PLWD and their caregivers, in relation to care setting and dementia severity, participants were recruited from the community and care homes in London. Semi-structured interviews were conducted, and medicines administration was observed in 4 care homes providing different types of care (nursing, residential, and mixed). Interviews were audio-recorded and transcribed verbatim. A conceptual model was developed based on a review of the literature; the domains provided the framework for thematic analysis of the data to achieve the research aim. Analysis was an iterative process and constant comparison was employed across interview transcripts. Results: Community results identified 6 areas that affect medication use; these are caregiver burden, the PLWDâs autonomy, scheduling and administering of medications, choice of formulations, interactions with formal care, and lack of medication information. Care home results also identified 6 areas; organisational aspects of the medication round, interactions between staff and residents, the residentsâ autonomy, choice of formulation, staff knowledge, and interactions within the care home. Findings have also identified how key changes along dementia progression affect medication use. These include the development of swallowing difficulties, increase in the number and variety of medications, appropriateness of formulations, decline in cognition and communication, behaviour changes, caregiver expectations for the future, the PLWDâs autonomy, transition from self to caregiver-led care, and changes in support needs. Conclusion: The study has identified challenges to medication use in PLWD and their caregivers along dementia progression and informed recommendations to optimise medication use and alleviate caregiver burden. Recommendations include a proposed medicines optimisation model for PLWD and their caregivers, suggestions for tailored consultations and medication use reviews, improvements for care home organisation, and specific recommendations for the pharmaceutical industry for the development of dementia-friendly formulations. Furthermore, suggestions are proposed to adapt the Family Caregiver Medication Administration Hassles Scale for caregivers of PLWD based on the findings
A Pathogenic Isolate of Monopartite PepYLCV DNA A-like Genome Differs Significantly in C1 Gene and CR Sequence, but not in their other Genes
Background and Objective: In order to elucidate pathogenic determining factor of pepper yellow leaf curl virus isolated from a lowland chili pepper cultivation field in West Sumatra, Indonesia, a whole genome analysis via primer walking strategy was conducted. Materials and Methods: The whole DNA A-like genome sequence of PepYLCIpsV was elucidated via five steps of primer walking, started with universal primers PAR1c715 and PAL1v1978 as the start point. Results: Whole genome comparison analysis identified only one single base insertion/deletion event located in the common region from a previously described isolate collected from the upland location (PepYLCItdV). The BLAST comparison on the nucleotide level showed 90.6% maximal homology with the existing DNA A-like genome from many pepper yellow leaf curl viruses deposited in public database so far. Further detail comparison each of six Open Reading Frames (ORFs) between PepYLCIpsV and PpepYLCItdV indicated that V1 and V2 displayed 94-95% homology, respectively, while C2 and C3 had homology in range of 99 and 97%, respectively. Interestingly C1 and C4 showed homology only 79 and 68%, respectively and the Common Region (CR) shared only 74% similarity. Conclusion: The C1 and CR could be the determining factors for the pathogenicity, therefore, characterizing of these two regions in the population could be used for management and controlling of the virus. The pathogenic isolate PepYLCIpsV (KT809345) appears to be derived by recombination from two isolates originating from different regions and hosts. Its existence seems to be more ancient than its currently mild dominant counterpart PepYLCItdV (KT809346)
The evolution of early childhood education policy in Hong Kong
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Familywise error control in multi-armed response-adaptive trials.
Response-adaptive designs allow the randomization probabilities to change during the course of a trial based on cumulated response data so that a greater proportion of patients can be allocated to the better performing treatments. A major concern over the use of response-adaptive designs in practice, particularly from a regulatory viewpoint, is controlling the type I error rate. In particular, we show that the naĂŻve z-test can have an inflated type I error rate even after applying a Bonferroni correction. Simulation studies have often been used to demonstrate error control but do not provide a guarantee. In this article, we present adaptive testing procedures for normally distributed outcomes that ensure strong familywise error control by iteratively applying the conditional invariance principle. Our approach can be used for fully sequential and block randomized trials and for a large class of adaptive randomization rules found in the literature. We show there is a high price to pay in terms of power to guarantee familywise error control for randomization schemes with extreme allocation probabilities. However, for proposed Bayesian adaptive randomization schemes in the literature, our adaptive tests maintain or increase the power of the trial compared to the z-test. We illustrate our method using a three-armed trial in primary hypercholesterolemia.DSR and JMSW were funded by the Medical Research Council, grant code MC_UU_00002/6. DSR was also funded by the Biometrika Trust
Cross-validated risk scores adaptive enrichment (CADEN) design
\ua9 2024 The AuthorsWe propose a Cross-validated ADaptive ENrichment design (CADEN) in which a trial population is enriched with a subpopulation of patients who are predicted to benefit from the treatment more than an average patient (the sensitive group). This subpopulation is found using a risk score constructed from the baseline (potentially high-dimensional) information about patients. The design incorporates an early stopping rule for futility. Simulation studies are used to assess the properties of CADEN against the original (non-enrichment) cross-validated risk scores (CVRS) design which constructs a risk score at the end of the trial. We show that when there exists a sensitive group of patients, CADEN achieves a higher power and a reduction in the expected sample size compared to the CVRS design. We illustrate the application of the design in two real clinical trials. We conclude that the new design offers improved statistical efficiency over the existing non-enrichment method, as well as increased benefit to patients. The method has been implemented in an R package caden
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