200 research outputs found
Predictive ability of the Desire to Avoid Pregnancy scale
BACKGROUND: A longstanding gap in the reproductive health field has been the availability of a screening instrument that can reliably predict a person's likelihood of becoming pregnant. The Desire to Avoid Pregnancy Scale is a new measure; understanding its sensitivity and specificity as a screening tool for pregnancy as well as its predictive ability and how this varies by socio-demographic factors is important to inform its implementation. METHODS: This analysis was conducted on a cohort of 994 non-pregnant participants recruited in October 2018 and followed up for one year. The cohort was recruited using social media as well as advertisements in a university, school, abortion clinic and outreach sexual health service. Almost 90% of eligible participants completed follow-up at 12 months; those lost to follow-up were not significantly different on key socio-demographic factors. We used baseline DAP score and a binary variable of whether participants experienced pregnancy during the study to assess the sensitivity, specificity, area under the ROC curve (AUROC) and positive and negative predictive values (PPV and NPV) of the DAP at a range of cut-points. We also examined how the predictive ability of the DAP varied according to socio-demographic factors and by the time frame considered (e.g., pregnancy within 3, 6, 9 and 12 months). RESULTS: At a cut-point of 2 on the 0-4 range of the DAP scale, the DAP had a sensitivity of 0.78, a specificity of 0.81 and an excellent AUROC of 0.87. In this sample the cumulative incidence of pregnancy was 16% (95%CI 13%, 18%) making the PPV 43% and the NPV 95% at this cut-point. The DAP score was the factor most strongly associated with pregnancy, even after age and number of children were taken into account. The association between baseline DAP score and pregnancy did not differ across time frames. CONCLUSIONS: This is the first study to assess the DAP scale as a screening tool and shows that its predictive ability is superior to the limited pre-existing pregnancy prediction tools. Based on our findings, the DAP could be used with a cut-point selected according to the purpose
TB58: Further Evaluation of Entomogenous Fungi as a Biological Agent of Aphid Control in Northeastern Maine
An intensive survey and study were made each year from 1952 through 1962 to determine seasonal abundance of living and dead diseased aphids by species on potatoes and to collect many of the infected specimens for exact diagnosis. Results of the study disclosed that the action of entomogenous fungi was outstanding in reducing the size of aphid populations on potatoes. This technical bulletin reports on the results of the continuance of the study from 1963 through 1969. However, the collection of dead, diseased aphids throughout the summer was done only from 1963 through 1966 ; thereafter, diagnosis was limited to dead, diseased specimens intensively collected from potatoes during a 1-week period when fungal activity was greatest. This was usually in mid-August, near the seasonal peak of aphid abundance on potatoes not treated with insecticides.https://digitalcommons.library.umaine.edu/aes_techbulletin/1131/thumbnail.jp
Desire to Avoid Pregnancy scale:clinical considerations and comparison with other questions about pregnancy preferences
BACKGROUND: Clinicians and women of reproductive age would benefit from a reliable way to identify who is likely to become pregnant in the next year, in order to direct health advice. The 14-item Desire to Avoid Pregnancy (DAP) scale is predictive of pregnancy; this paper compares it with other ways of assessing pregnancy preferences to shortlist options for clinical implementation. METHODS: A cohort of 994 UK women of reproductive age completed the DAP and other questions about pregnancy preferences, including the Attitude towards Potential Pregnancy Scale (APPS), at baseline and reported on pregnancies quarterly for a year. For each question, DAP item and combinations of DAP items, we examined the predictive ability, sensitivity, specificity, area under the receiver operating curve (AUROC), and positive and negative predictive values. RESULTS: The AUROCs and predictive ability of the APPS and DAP single items were weaker than the full DAP, though all except one had acceptable AUROCs (>0.7). The most predictive individual DAP item was 'It would be a good thing for me if I became pregnant in the next 3 months', where women who strongly agreed had a 66.7% chance of pregnancy within 12 months and the AUROC was acceptable (0.77). CONCLUSION: We recommend exploring the acceptability to women and healthcare professionals of asking a single DAP item ('It would be a good thing for me if I became pregnant in the next 3 months'), possibly in combination with additional DAP items. This will help to guide service provision to support reproductive preferences
The myriad challenges of the Paris Agreement
The much awaited and intensely negotiated Paris Agreement was adopted on 12 December 2015 by the Parties to the United Nations Framework Convention on Climate Change. The agreement set out a more ambitious long-term temperature goal than many had anticipated, implying more stringent emissions reductions that have been under-explored by the research community. By its very nature a multidisciplinary challenge, filling the knowledge gap requires not only climate scientists, but the whole Earth system science community, as well as economists, engineers, lawyers, philosophers, politicians, emergency planners and others to step up. To kick start cross-disciplinary discussions, the University of Oxford's Environmental Change Institute focused its 25th anniversary conference upon meeting the challenges of the Paris Agreement for science and society. This theme issue consists of review papers, opinion pieces and original research from some of the presentations within that meeting, covering a wide range of issues underpinning the Paris Agreement
Mutation of the Mouse Syce1 Gene Disrupts Synapsis and Suggests a Link between Synaptonemal Complex Structural Components and DNA Repair
In mammals, the synaptonemal complex is a structure required to complete crossover recombination. Although suggested by cytological work, in vivo links between the structural proteins of the synaptonemal complex and the proteins of the recombination process have not previously been made. The central element of the synaptonemal complex is traversed by DNA at sites of recombination and presents a logical place to look for interactions between these components. There are four known central element proteins, three of which have previously been mutated. Here, we complete the set by creating a null mutation in the Syce1 gene in mouse. The resulting disruption of synapsis in these animals has allowed us to demonstrate a biochemical interaction between the structural protein SYCE2 and the repair protein RAD51. In normal meiosis, this interaction may be responsible for promoting homologous synapsis from sites of recombination
Phylogenomic analysis of gastroenteritis-associated Clostridium perfringens in England and Wales over a 7-year period indicates distribution of clonal toxigenic strains in multiple outbreaks and extensive involvement of enterotoxin-encoding (CPE) plasmids
Clostridium perfringens is a major enteric pathogen known to cause gastroenteritis in human adults. Although major outbreak cases are frequently reported, only limited whole-genome sequencing (WGS) based studies have been performed to understand the genomic epidemiology and virulence gene content of outbreak-associated C. perfringens strains. We performed phylogenomic analysis on 109 C. perfringens isolates (human and food) obtained from disease cases in England and Wales between 2011 and 2017. Initial findings highlighted the enhanced discriminatory power of WGS in profiling outbreak C. perfringens strains, when compared to the current Public Health England referencing laboratory technique of fluorescent amplified fragment length polymorphism analysis. Further analysis identified that isogenic C. perfringens strains were associated with nine distinct care-home-associated outbreaks over the course of a 5-year interval, indicating a potential common source linked to these outbreaks or transmission over time and space. As expected, the enterotoxin cpe gene was encoded in all but 4 isolates (96.3 %; 105/109), with virulence plasmids encoding cpe (particularly pCPF5603 and pCPF4969 plasmids) extensively distributed (82.6 %; 90/109). Genes encoding accessory virulence factors, such as beta-2 toxin, were commonly detected (46.7 %; 51/109), and genes encoding phage proteins were also frequently identified. Overall, this large-scale genomic study of gastroenteritis-associated C. perfringens suggested that three major cpe-encoding (toxinotype F) genotypes underlie these outbreaks: strains carrying (1) pCPF5603 plasmid, (2) pCPF4969 plasmid and (3) chromosomal-cpe strains. Our findings substantially expanded our knowledge on type F C. perfringens involved in human-associated gastroenteritis, with further studies required to fully probe the dissemination and regional reservoirs of this enteric pathogen, which may help devise effective prevention strategies to reduce the food-poisoning disease burden in vulnerable patients, such as the elderly
ZraP is a periplasmic molecular chaperone and a repressor of the zinc-responsive two-component regulator ZraSR
The bacterial envelope is the interface with the surrounding environment and is consequently subjected to a barrage of noxious agents including a range of compounds with antimicrobial activity. The ESR (envelope stress response) pathways of enteric bacteria are critical for maintenance of the envelope against these antimicrobial agents. In the present study, we demonstrate that the periplasmic protein ZraP contributes to envelope homoeostasis and assign both chaperone and regulatory function to ZraP from Salmonella Typhimurium. The ZraP chaperone mechanism is catalytic and independent of ATP; the chaperone activity is dependent on the presence of zinc, which is shown to be responsible for the stabilization of an oligomeric ZraP complex. Furthermore, ZraP can act to repress the two-component regulatory system ZraSR, which itself is responsive to zinc concentrations. Through structural homology, ZraP is a member of the bacterial CpxP family of periplasmic proteins, which also consists of CpxP and Spy. We demonstrate environmental co-expression of the CpxP family and identify an important role for these proteins in Salmonella's defence against the cationic antimicrobial peptide polymyxin B
Cardiac mTOR complex 2 preserves ventricular function in pressure-overload hypertrophy
Mammalian target of rapamycin (mTOR), a central regulator of growth and metabolism, has tissue-specific functions depending on whether it is part of mTOR complex 1 (mTORC1) or mTORC2. We have previously shown that mTORC1 is required for adaptive cardiac hypertrophy and maintenance of function under basal and pressure-overload conditions. In the present study, we aimed to identify functions of mTORC2 in the heart.; Using tamoxifen-inducible cardiomyocyte-specific gene deletion, we generated mice deficient for cardiac rapamycin-insensitive companion of mTOR (rictor), an essential and specific component of mTORC2. Under basal conditions, rictor deficiency did not affect cardiac growth and function in young mice and also had no effects in adult mice. However, transverse aortic constriction caused dysfunction in the rictor-deficient hearts, whereas function was maintained in controls after 1 week of pressure overload. Adaptive increases in cardiac weight and cardiomyocyte cross-sectional area, fibrosis, and hypertrophic and metabolic gene expression were not different between the rictor-deficient and control mice. In control mice, maintained function was associated with increased protein levels of rictor, protein kinase C (PKC)βII, and PKCδ, whereas rictor ablation abolished these increases. Rictor deletion also significantly decreased PKCε at baseline and after pressure overload. Our data suggest that reduced PKCε and the inability to increase PKCβII and PKCδ abundance are, in accordance with their known function, responsible for decreased contractile performance of the rictor-deficient hearts.; Our study demonstrates that mTORC2 is implicated in maintaining contractile function of the pressure-overloaded male mouse heart
Analysis of SMALP co-extracted phospholipids shows distinct membrane environments for three classes of bacterial membrane protein
Biological characterisation of membrane proteins lags behind that of soluble proteins. This reflects issues with the traditional use of detergents for extraction, as the surrounding lipids are generally lost, with adverse structural and functional consequences. In contrast, styrene maleic acid (SMA) copolymers offer a detergent-free method for biological membrane solubilisation to produce SMA-lipid particles (SMALPs) containing membrane proteins together with their surrounding lipid environment. We report the development of a reverse-phase LC-MS/MS method for bacterial phospholipids and the first comparison of the profiles of SMALP co-extracted phospholipids from three exemplar bacterial membrane proteins with different topographies: FtsA (associated membrane protein), ZipA (single transmembrane helix), and PgpB (integral membrane protein). The data showed that while SMA treatment per se did not preferentially extract specific phospholipids from the membrane, SMALP-extracted ZipA showed an enrichment in phosphatidylethanolamines and depletion in cardiolipins compared to the bulk membrane lipid. Comparison of the phospholipid profiles of the 3 SMALP-extracted proteins revealed distinct lipid compositions for each protein: ZipA and PgpB were similar, but in FtsA samples longer chain phosphatidylglycerols and phosphatidylethanolamines were more abundant. This method offers novel information on the phospholipid interactions of these membrane proteins
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