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Visualising disease progression on multiple variables with vector plots and path plots.
BACKGROUND: It is often desirable to observe how a disease progresses over time in individual patients, rather than graphing group averages; and since multiple outcomes are typically recorded on each patient, it would be advantageous to visualise disease progression on multiple variables simultaneously. METHODS: A variety of vector plots and a path plot have been developed for this purpose, and data from a longitudinal Huntington's disease study are used to illustrate the utility of these graphical methods for exploratory data analysis. RESULTS: Initial and final values for three outcome variables can be easily visualised per patient, along with the change in these variables over time. In addition to the disease trajectory, the path individual patients take from initial to final observation can be traced. Categorical variables can be coded with different types of vectors or paths (e.g. different colours, line types, line thickness) and separate panels can be used to include further categorical or continuous variables, allowing clear visualisation of further information for each individual. In addition, summary statistics such as mean vectors, bivariate interquartile ranges and convex polygons can be included to assist in interpreting trajectories, comparing groups, and detecting multivariate outliers. CONCLUSION: Vector and path plots are useful graphical methods for exploratory data analysis when individual-level information on multiple variables over time is desired, and they have several advantages over plotting each variable separately.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Merging enzymes with chemocatalysis for amide bond synthesis
Amides are one of the most fundamental chemical bonds in nature. In addition to proteins and other metabolites, many valuable synthetic products comprise amide bonds. Despite this, there is a need for more sustainable amide synthesis. Herein, we report an integrated next generation multi-catalytic system, merging nitrile hydratase enzymes with a Cu-catalysed N-arylation reaction in a single reaction vessel, for the construction of ubiquitous amide bonds. This synergistic one-pot combination of chemo- and biocatalysis provides an amide bond disconnection to precursors, that are orthogonal to those in classical amide synthesis, obviating the need for protecting groups and delivering amides in a manner unachievable using existing catalytic regimes. Our integrated approach also affords broad scope, very high (molar) substrate loading, and has excellent functional group tolerance, telescoping routes to natural product derivatives, drug molecules, and challenging chiral amides under environmentally friendly conditions at scale
Association of type of birth attendant and place of delivery on infant mortality in sub-Saharan Africa
Objective: To examine the association between type of birth attendant and place of delivery, and infant mortality (IM).Methods: This cross-sectional study used self-reported data from the Demographic Health Surveys for women in Ghana, Kenya, and Sierra Leone. Logistic regression estimated odds ratios (ORs) and95% confidence intervals.Results: In Ghana and Sierra Leone, odds of IM were higher for women who delivered at a health facility versus women who delivered at a household residence (OR=3.18, 95% confidence interval, CI: 1.29-7.83, p=0.01 and OR=1.62, 95% CI: 1.15-2.28, p=0.01, respectively). Compared to the use of health professionals, the use of birth attendants for assistance with delivery was not significantly associated with IM for women in Ghana or Sierra Leone (OR=2.17, 95% CI: 0.83-5.69, p=0.12 and OR=1.25, 95% CI: 0.92-1.70, p=0.15, respectively). In Kenya, odds of IM, though nonsignificant, were lower for women who used birth attendants than those who used health professionals to assist with delivery (OR=0.85, 95% CI: 0.51-1.41, p=0.46), and higher with delivery at a health facility versus a household residence (OR=1.29, 95% CI: 0.81-2.03, p=0.28).Conclusions: Women in Ghana and Sierra Leone who delivered at a health facility had statistically significant increased odds of IM. Birth attendant type-IM associations were not statistically significant.Future research should consider culturally-sensitive interventions to improve maternal health and help reduce IM.Keywords: birth attendant, infant mortality, sub-Saharan Afric
A longitudinal investigation of childhood communication ability and adolescent psychotic experiences in a community sample
Background:
Some childhood speech and language impairments precede psychosis but it is not clear whether they also precede adolescent psychotic experiences and whether this association is specific to psychotic experiences.
Methods:
Pragmatic language and expressive speech and language (parent-assessed using the Children's Communication Checklist) at age 9 and psychotic experiences and depression at ages 12 and 18 were investigated in 7659 participants from the Avon Longitudinal Study of Parents and Children. Associations were investigated using multivariate modelling.
Results:
Poorer pragmatic language at 9 years was associated with psychotic experiences at both ages (12 years OR 1.22, 95% CI 1.11, 1.34; 18 years OR 1.25, 95% CI 1.10, 1.41) but only with depression at 18 years (OR 1.10, 95% CI 1.00, 1.22). Poorer expressive speech and language ability was not associated with psychotic experiences or depression at either age. There was evidence that pragmatic language was specifically associated with psychotic experiences at age 12 but no evidence that the strength of any of the associations changed over time.
Conclusions:
Deficits in pragmatic language precede early and late adolescent psychotic experiences and early adolescent depression. Interventions aimed at helping children improve pragmatic language skills may reduce the incidence of adolescent psychopathology and associated psychological disorder and dysfunction later in life
Management Information Systems Education: A Systematic Review
Management information systems (MIS) programs were developed to prepare graduates to create innovative solutions to problems where business and technology intersect. As such, the curricula must change rapidly to stay current with industry standards, an accelerating moving target. This research presents the findings of a systematic literature review to identify and present trends in the scholarly literature on MIS education. The purpose of this approach was to understand how academia ensures students are prepared for industry and keeps pace with changing industry needs. Key findings from the literature are presented, as well as a compilation of areas for future research. Overwhelmingly, a lack of international perspective was identified as the vast majority of articles collected data in the US. Further, the direction of future research and exploration revolved around five themes of innovative pedagogical approaches, industry partnerships, subtopics of MIS education, new methods and metrics for measuring success in MIS education, and cross-disciplinary opportunities in fields such as mathematics, traditional business disciplines, and the hard sciences
Omega-3 and Omega-6 Fatty acids and risk of psychotic outcomes in the ALSPAC birth cohort
Background
Long chain polyunsaturated fatty acid (PUFA) levels have been implicated in the pathology of psychotic disorders. We investigated the relationship between childhood PUFA levels and later psychotic experiences (PE's) in a large birth cohort.
Methods
Plasma levels of Ω-3 and Ω-6 fatty acids (FA's) were assayed at ages 7 and 16 years. PE's were assessed at ages 12 and 18 years using a semi-structured interview. Primary outcome was any PE's at 18 years; sensitivity analyses examined incident PE's between ages 12 and 18 years, persistent PE's (at 12 and 18) and psychotic disorder at 18 years. Genetic instruments for Ω-3 and Ω-6 were derived and used in a multivariable Mendelian Randomization analysis.
Results
Higher levels of Ω-6 FA's AA, OA and AdA at age 7 years were weakly associated with a reduced risk for PE's at 18 years, however, effect sizes were small and attenuated after adjusting for confounders (strongest evidence for OA; adjusted OR, 0.842; 95% CI, 0.711, 0.998; p, 0.048). Total Ω-6 levels at age 16 years were associated with an increased odds of psychotic disorder at age 18 years. However, there was no association between Ω-6/Ω-3 ratio and psychosis outcomes, nor with genetic instruments of total Ω-3 or Ω-6 levels.
Conclusions
There is no strong evidence that total plasma Ω-3 FA levels or Ω-6/Ω-3 ratios in childhood and mid-adolescence are associated with increased risk for PE's or psychotic disorder, but very marginal evidence that alterations in the Ω-6 pathway at developmental time points might influence risk2
Tissue Penetration of Meropenem in Patients Undergoing Gynecologic Surgery
The purpose of this study was to assess the tissue-penetrating ability of a new β-lactam antibiotic, meropenem, in 64 patients undergoing elective gynecologic surgery. Patients received a single 500-mg dose intravenously before surgery. Plasma and tissue concentrations of meropenem were highest at ∼1 hour, and good tissue penetration was seen in the variety of specimens evaluated. The median plasma concentration at ∼1 hour was 13.3 µg/mL. The median fluid and tissue concentrations at ∼1 hour were as follows: cervix, 8.5 µg/g; endometrium, 2.3 µg/g; fallopian tube, 1.9 µg/g; myometrium, 3.6 µg/g; ovary, 2.3 µg/g; and uterus, 2.3 µg/g. These tissue concentrations exceed the MICs of meropenem for 90% of typical pathogens associated with gynecologic infections. Meropenem readily penetrates gynecologic tissue. A single 500-mg dose provides adequate tissue concentrations for treatment of gynecologic infections caused by susceptible pathogen
Aerobic capacity and upper limb strength are reduced in women diagnosed with breast cancer: a systematic review
AbstractQuestion: What are typical values of physical function for women diagnosed with breast cancer and how do these compare to normative data? Design: Systematic review with meta-analysis. Participants: Women diagnosed with breast cancer who were before, during or after treatment. Outcome measures: Physical function was divided into three categories: aerobic capacity, upper and lower extremity muscular fitness, and mobility. Measures of aerobic capacity included field tests (6-minute walk test, 12-minute walk tests, Rockport 1-mile test, and 2-km walk time) and submaximal/maximal exercise tests on a treadmill or cycle ergometer. Measures of upper and lower extremity muscular fitness included grip strength, one repetition maximum (bench, chest or leg press), muscle endurance tests, and chair stands. The only measure of mobility was the Timed Up and Go test. Results: Of the 1978 studies identified, 85 were eligible for inclusion. Wide ranges of values were reported, reflecting the range of ages, disease severity, treatment type and time since treatment of participants. Aerobic fitness values were generally below average, although 6-minute walk time was closer to population norms. Upper and lower extremity strength was lower than population norms for women who were currently receiving cancer treatment. Lower extremity strength was above population norms for women who had completed treatment. Conclusion: Aerobic capacity and upper extremity strength in women diagnosed with breast cancer are generally lower than population norms. Assessment of values for lower extremity strength is less conclusive. As more research is published, expected values for sub-groups by age, treatment, and co-morbidities should be developed. [Neil-Sztramko SE, Kirkham AA, Hung SH, Niksirat N, Nishikawa K Campbell KL (2014) Aerobic capacity and upper limb strength are reduced in women diagnosed with breast cancer: a systematic review. Journal of Physiotherapy 60: 189–200
Manipulation of P-TEFb control machinery by HIV: recruitment of P-TEFb from the large form by Tat and binding of HEXIM1 to TAR
Basal transcription of the HIV LTR is highly repressed and requires Tat to recruit the positive transcription elongation factor, P-TEFb, which functions to promote the transition of RNA polymerase II from abortive to productive elongation. P-TEFb is found in two forms in cells, a free, active form and a large, inactive complex that also contains 7SK RNA and HEXIM1 or HEXIM2. Here we show that HIV infection of cells led to the release of P-TEFb from the large form. Consistent with Tat being the cause of this effect, transfection of a FLAG-tagged Tat in 293T cells caused a dramatic shift of P-TEFb out of the large form to a smaller form containing Tat. In vitro, Tat competed with HEXIM1 for binding to 7SK, blocked the formation of the P-TEFb–HEXIM1–7SK complex, and caused the release P-TEFb from a pre-formed P-TEFb–HEXIM1–7SK complex. These findings indicate that Tat can acquire P-TEFb from the large form. In addition, we found that HEXIM1 binds tightly to the HIV 5′ UTR containing TAR and recruits and inhibits P-TEFb activity. This suggests that in the absence of Tat, HEXIM1 may bind to TAR and repress transcription elongation of the HIV LTR
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