543 research outputs found
Prevalence of asymptomatic bacteriuria among pre-school children in Nnewi, South-East Nigeria
Background: Early diagnosis and management of urinary tract infection (UTI) in young children reduces the risk of renal scarring and chronic renalinsufficiency. We determined the prevalence of asymptomatic bacteriuria(ASB) among pre-school children in Nnewi, South-East Nigeria.Methodology: This was a crosssectional survey involving apparently healthy nursery school children aged 3-5 years. A pre-tested, care-giver administered questionnaire was used to obtain information about the participants including age, sex, history of fever and antibiotic administration in the two weeks preceding the study. Following a clinical examination, a sample of mid-stream urine was collected from each participant for dipstick urinalysis, and urine microscopy and culture. ASB was defined as the presence of .105CFU/ml of urine in a participantwho had no symptoms of UTI.Results: Out of 792 children, 417 (52.3%) were females and 375 (47.4%) were males. The mean age of the children was 4.0 } 0.7 years. ASB was found in 31 children (4%). The prevalence of ASB in females (7.2%) was significantly higher than in males (0.5%), p<0.001. The highest prevalenceof ASB of 5.6% occurred in the 4-year-olds and the lowest of 2.0 %occurred in 5 year olds, p=0.09. The commonest bacterial isolates among the ASB cases were Staphlococcus aureus, 13 (40.6%); Streptococcus faecalis, 9 (28.1%) and Escherichia coli, 5 (15.6%). Conclusion: Asymptomatic bacteriuria is commoner in female preschoolchildren and S. aureus is the commonest bacterial isolate. Routine evaluation of female preschool children for bacteriuria is recommended.Key words: Asymptomatic bacteriuria, Pre-school children, Prevalenc
Risk factors for prosthetic joint infections following total hip arthroplasty based on 33,337 hips in the Finnish Arthroplasty Register from 2014 to 2018
Background and purpose - Periprosthetic joint infection (PJI) is a devastating complication and more information on risk factors for PJI is required to find measures to prevent infections. Therefore, we assessed risk factors for PJI after primary total hip arthroplasty (THA) in a large patient cohort. Patients and methods - We analyzed 33,337 primary THAs performed between May 2014 and January 2018 based on the Finnish Arthroplasty Register (FAR). Cox proportional hazards regression was used to estimate hazard ratios with 95% confidence intervals (CI) for first PJI revision operation using 25 potential patient- and surgical-related risk factors as covariates. Results - 350 primary THAs were revised for the first time due to PJI during the study period. The hazard ratios for PJI revision in multivariable analysis were 2.0 (CI 1.3-3.2) for ASA class II and 3.2 (2.0-5.1) for ASA class III-IV compared with ASA class I, 1.4 (1.1-1.7) for bleeding > 500 mL compared with 120 minutes compared with 45-59 minutes, and 2.6 (1.4-4.9) for simultaneous bilateral operation. In the univariable analysis, hazard ratios for PJI revision were 2.3 (1.7-3.3) for BMI of 31-35 and 5.0 (3.5-7.1) for BMI of > 35 compared with patients with BMI of 21-25. Interpretation - We found several modifiable risk factors associated with increased PJI revision risk after THA to which special attention should be paid preoperatively. In particular, high BMI may be an even more prominent risk factor for PJI than previously assessed.Peer reviewe
Spirometry Abnormalities and Its Associated Factors Among Primary School Children in a Nigerian City.
BACKGROUND: There is paucity of data on objectively measured lung function abnormalities in Nigerian children using diagnostic testing methods such as spirometry. Such assessments could prompt early diagnosis and therapeutic interventions. METHODS: This was a cross sectional study among children aged 6 to 12 years in South-Eastern Nigeria. We selected participants from one school using a multistage stratified random sampling technique. A structured respiratory questionnaire was administered to obtain necessary data. The lung functions of the children were measured by spirometry. We used Lower Limits of Normal (LLN) based on GLI reference equations for African-American and mixed ethnicities to define abnormal spirometry. We studied the association between the exposures and lung function using logistic regression/chi-squared tests. RESULTS: A total of 145 children performed acceptable and repeatable tests. There were 73 males (50.3%), mean age of 9.13 years (+1.5) and age range 6 to 12 years. Frequency of respiratory symptoms was cough- 64 (44.1%) and wheeze in 19 (13.1%). Using GLI for African-Americans, fifty-five (37.9%) children had abnormal spirometryobstructive pattern in 40 (27.6%) and restrictive pattern in 15 (10.3%). The two references showed significant differences in interpretation of abnormality (χ2 = 72.86; P < .001). Respiratory symptom-wheeze was an independent determinant of abnormal lung function in this population.(OR = 0.31; 95%CI: 0.10-0.94; P = .04). CONCLUSION: There is a high burden of respiratory symptoms and abnormal spirometry among these children. The need for objective evaluation of lung function especially for children with respiratory symptoms is evident
Uncertainty in humanities network visualization
Network visualization is one of the most widely used tools in digital humanities research. The idea of uncertain or “fuzzy” data is also a core notion in digital humanities research. Yet network visualizations in digital humanities do not always prominently represent uncertainty. In this article, we present a mathematical and logical model of uncertainty as a range of values which can be used in network visualizations. We review some of the principles for visualizing uncertainty of different kinds, visual variables that can be used for representing uncertainty, and how these variables have been used to represent different data types in visualizations drawn from a range of non-humanities fields like climate science and bioinformatics. We then provide examples of two diagrams: one in which the variables displaying degrees of uncertainty are integrated/pinto the graph and one in which glyphs are added to represent data certainty and uncertainty. Finally, we discuss how probabilistic data and what-if scenarios could be used to expand the representation of uncertainty in humanities network visualizations
An unbiased in vitro screen for activating epidermal growth factor receptor mutations
Cancer tissues harbor thousands of mutations, and a given oncogene may
be mutated at hundreds of sites. Yet, only a few of these mutations have
been functionally tested. Here, we describe an unbiased platform for
the functional characterization of thousands of variants of a single
receptor tyrosine kinase (RTK) gene in a single assay. Our in vitro screen for activating mutations
(iSCREAM) platform enabled rapid analysis of mutations conferring
gain-of-function RTK activity promoting clonal growth. The screening
strategy included a somatic model of cancer evolution and utilized a
library of 7,216 randomly mutated epidermal growth factor receptor
(EGFR) single-nucleotide variants, that were tested in murine lymphoid
Ba/F3 cells. These cells depend on exogenous interleukin-3 (IL-3) for
growth, but this dependency can be compensated by ectopic EGFR
overexpression, enabling selection for gain-of-function EGFR
mutants. Analysis of the enriched mutants revealed EGFR A702V, a novel
activating variant that structurally stabilized the EGFR kinase dimer
interface and conferred sensitivity to kinase inhibition by afatinib. As
proof of concept for our approach, we recapitulated clinical
observations and identified the EGFR L858R as the major enriched EGFR
variant. Altogether iSCREAM enabled robust enrichment of 21 variants
from a total of 7,216 EGFR mutations. These findings indicate the
power of this screening platform for unbiased identification of
activating RTK variants that are enriched under selection pressure in a
model of cancer heterogeneity and evolution
Learned helplessness in chess players: The importance of task similarity and the role of skill
The effects of noncontingency between subjects' responses and outcomes were examined with respect to treatment/posttest similarity and skill in the task. The experimental design consisted of three groups. The first group had to solve chess problems with objective solutions and received veridical feedback; each member of the second group faced problems with no objective solutions, and received the same feedback as the member of the first group he was yoked with, but without any control on it; the control group received a waiting task. It was found that the group with unsolvable problems was more depressed than the two other groups at the end of the experiment. The mid-strength players were the most sensitive to the manipulation, and the weakest players showed little effect of learned helplessness. It was also found that the effects were proportional to the degree of similarity between the treatment and the posttest. The results limit the domain of applicability of the learned helplessness model
Selective loss of kisspeptin signaling in oocytes causes progressive premature ovulatory failure
Study question: Does direct kisspeptin signaling in the oocyte have a role in the control of follicular dynamics and ovulation?Summary answer: Kisspeptin signaling in the oocyte plays a relevant physiological role in the direct control of ovulation; oocyte-specific ablation of kisspeptin receptor, Gpr54, induces a state of premature ovulatory failure in mice that recapitulates some features of premature ovarian insufficiency (POI).What is known already: Kisspeptins, encoded by the Kiss1 gene, are essential for the control of ovulation and fertility, acting primarily on hypothalamic GnRH neurons to stimulate gonadotropin secretion. However, kisspeptins and their receptor, Gpr54, are also expressed in the ovary of different mammalian species, including humans, where their physiological roles remain contentious and poorly characterized.Study design, size, duration: A novel mouse line with conditional ablation of Gpr54 in oocytes, named OoGpr54-/-, was generated and studied in terms of follicular and ovulatory dynamics at different age-points of postnatal maturation. A total of 59 OoGpr54-/- mice and 47 corresponding controls were analyzed. In addition, direct RNA sequencing was applied to ovarian samples from 8 OoGpr54-/- and 7 control mice at 6 months of age, and gonadotropin priming for ovulatory induction was conducted in mice (N = 7) from both genotypes.Participants/materials, setting, methods: Oocyte-selective ablation of Gpr54 in the oocyte was achieved in vivo by crossing a Gdf9-driven Cre-expressing transgenic mouse line with a Gpr54 LoxP mouse line. The resulting OoGpr54-/- mouse line was subjected to phenotypic, histological, hormonal and molecular analyses at different age-points of postnatal maturation (Day 45, and 2, 4, 6 and 10-11 months of age), in order to characterize the timing of puberty, ovarian follicular dynamics and ovulation, with particular attention to identification of features reminiscent of POI. The molecular signature of ovaries from OoGpr54-/- mice was defined by direct RNA sequencing. Ovulatory responses to gonadotropin priming were also assessed in OoGpr54-/- mice.Main results and the role of chance: Oocyte-specific ablation of Gpr54 caused premature ovulatory failure, with some POI-like features. OoGpr54-/- mice had preserved puberty onset, without signs of hypogonadism. However, already at 2 months of age, 40% of OoGpr54-/- females showed histological features reminiscent of ovarian failure and anovulation. Penetrance of the phenotype progressed with age, with >80% and 100% of OoGpr54-/- females displaying complete ovulatory failure by 6- and 10 months, respectively. This occurred despite unaltered hypothalamic Gpr54 expression and gonadotropin levels. Yet, OoGpr54-/- mice had decreased sex steroid levels. While the RNA signature of OoGpr54-/- ovaries was dominated by the anovulatory state, oocyte-specific ablation of Gpr54 significantly up- or downregulated of a set of 21 genes, including those encoding pituitary adenylate cyclase-activating polypeptide, Wnt-10B, matrix-metalloprotease-12, vitamin A-related factors and calcium-activated chloride channel-2, which might contribute to the POI-like state. Notably, the anovulatory state of young OoGpr54-/- mice could be rescued by gonadotropin priming.Large scale data: N/A. .Limitations, reasons for caution: Conditional ablation of Gpr54 in oocytes unambiguously caused premature ovulatory failure in mice; yet, the ultimate molecular mechanisms for such state of POI can be only inferred on the basis of RNAseq data and need further elucidation, since some of the molecular changes observed in OoGpr54-/- ovaries were secondary to the anovulatory state. Direct translation of mouse findings to human disease should be made with caution since, despite the conserved expression of Kiss1/kisspeptin and Gpr54 in rodents and humans, our mouse model does not recapitulate all features of common forms of POI.Wider implications of the findings: Deregulation of kisspeptin signaling in the oocyte might be an underlying, and previously unnoticed, cause for some forms of POI in women.Study funding/competing interest(s): This work was primarily supported by a grant to M.P. and M.T.-S. from the FiDiPro (Finnish Distinguished Professor) Program of the Academy of Finland. Additional financial support came from grant BFU2017-83934-P (M.T.-S.; Ministerio de Economía y Competitividad, Spain; co-funded with EU funds/FEDER Program), research funds from the IVIRMA International Award in Reproductive Medicine (M.T.-S.), and EFSD Albert Renold Fellowship Programme (S.T.R.). The authors have no conflicts of interest to declare in relation to the contents of this work.</p
Social Security Coverage and the Labor Market in Developing Countries
This paper analyzes the reasons behind the low rates of contribution to social security programs in developing countries. Using a large set of harmonized household surveys from Latin America we compare contribution patterns among wage employees, for whom participation is compulsory, with contribution patterns among self-employed workers, for whom participation is often voluntary. In all countries, contribution rates among salaried workers are similarly correlated with education, earnings, size of the employer, household characteristics and age. In addition, contribution patterns among salaried workers are highly correlated with contribution patterns among the self-employed. Our results indicate that on average more than 30 percent of the explained within-country variance in contributions patterns may be accounted for by individuals low willingness to participate in old-age pension programs. Nonetheless, we also find evidence suggesting that some workers are rationed out of social security against their will
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