2,064 research outputs found
Arsenic, chromium, copper, iron, manganese, lead, selenium and zinc in the tissues of the largemouth yellowfish, Labeobarbus kimberleyensis (Gilchrist and Thompson, 1913), from the Vaal Dam, South Africa, and associated consumption risks
This paper addresses the accumulation of trace elements in the water, sediment and tissues of Labeobarbus kimberleyensis from the Vaal Dam, South Africa. Fish were collected from the Vaal Dam during February to April 2011. Five organs, water and sediment were collected and trace element concentrations were measured with an ICP-MS. Target hazard quotients were calculated to assess the human health risk associated with consuming muscle tissue of this fish species. Trace element levels for Cu, Fe and Mn were higher in water and sediment compared to L. kimberleyensis. Sediment element levels were highest compared to water and fish. Clear trends in element accumulation by the different organs were observed. Liver and kidney accumulated the highest element concentrations, followed by the gills, muscle and spinal cord. Bioconcentration factors further supported the observation that trace element accumulation was lower in fish compared to sediment. The high sediment element levels indicate that there is a low bioavailability of elements for accumulation by biota in the Vaal Dam. Target hazard quotient determination indicated that risk associated with the consumption of muscle tissue fromL. kimberleyensis was low for most elements, except Cr and Se. Element levels in L. kimberleyensis, water and sediment have increased compared to previous studies on the Vaal Dam.Keywords: bioaccumulation; Labeobarbus kimberleyensis; risk assessment; target hazard quotient; trace element; Vaal Dam; water qualit
Assessing early memories of threat and subordination: Confirmatory factor analyisis of the early life experiences scale for adolescents.
The Early Life Experiences Scale (ELES) is a self-report questionnaire that assesses personal feelings of perceived threat and submissiveness in interactions within family. This paper presents the adaptation and validation of the ELES in Portuguese language for adolescents. The sample was composed of 771 adolescents from community schools with ages between 13 and 18 years old. Along with ELES, participants also answered the Early Memories of Warmth and Safeness Scale and the Positive and Negative Affect Schedule for Children and Adolescents. Confirmatory factor analysis (CFA) was performed to test the factor structure of the ELES and results confirm a three-factor structure, composed by Threat, Submissiveness and Unvalued dimensions. These emotional memories focused on perceived threat, submissiveness and unvalued seem to have a distinct nature. The scale also showed adequate internal consistency, good test-retest reliability and convergent validity with measures of positive emotional memories, positive and negative affect. There were sex differences for threat subscale and age differences for submissiveness subscale. Overall, these findings suggest that the ELES in its Portuguese version for adolescents may be a useful tool for research, educational and clinical contexts with school-aged adolescents
The Ctf18 RFC-like complex positions yeast telomeres but does not specify their replication time
Peer reviewedPreprin
Diagnosis and management of parathyroid carcinoma: a state-of-the-art review
Parathyroid carcinoma is one of the least common endocrine malignancies and accounts for approximately 1% of all patients with primary hyperparathyroidism. A systematic review of peer-reviewed literature published between January 2000 and March 2022 via Medline, Embase, Cochrane Central Register of Controlled Trials, EudraCT, ClinicalTrials.gov, CINAHL and SCOPUS was conducted. Manuscripts were eligible if they included data on adult non-pregnant populations with parathyroid carcinoma. No restrictions regarding interventions, comparators or duration of follow-up were imposed. Single case reports, reviews or meta-analyses were excluded. Outcomes of interest were molecular pathogenesis, clinical presentation, differential diagnosis, treatment, follow-up and overall survival. Study quality was evaluated using the Newcastle-Ottawa Scale for observational studies. This review included 75 studies from 17 countries, reporting on more than 3000 patients with parathyroid carcinoma. CDC73 mutation has been recognised as playing a pivotal role in molecular pathogenesis. Parathyroid carcinoma typically presents with markedly increased calcium and parathyroid hormone levels. The most frequently described symptoms were bone and muscle pain or weakness. En bloc resection remains the gold standard for the surgical approach. The 5-year overall survival ranged from 60 to 93%, with resistant hypercalcaemia a significant cause of mortality. Emerging evidence indicating that targeted therapy, based on molecular biomarkers, presents a novel treatment option. The rarity of PC and need for personalised treatment warrant multidisciplinary management in a 'centre of excellence' with a track record in PC management
To Clone or Not To Clone: Method Analysis for Retrieving Consensus Sequences In Ancient DNA Samples
The challenges associated with the retrieval and authentication of ancient DNA (aDNA) evidence are principally due to post-mortem damage which makes ancient samples particularly prone to contamination from “modern” DNA sources. The necessity for authentication of results has led many aDNA researchers to adopt methods considered to be “gold standards” in the field, including cloning aDNA amplicons as opposed to directly sequencing them. However, no standardized protocol has emerged regarding the necessary number of clones to sequence, how a consensus sequence is most appropriately derived, or how results should be reported in the literature. In addition, there has been no systematic demonstration of the degree to which direct sequences are affected by damage or whether direct sequencing would provide disparate results from a consensus of clones
Recommended from our members
Urinary tract infections and antibiotic use in pregnancy - qualitative analysis of online forum content
Background Antibiotics are standard treatment for asymptomatic and symptomatic urinary tract infections (UTIs) in pregnancy. Their overuse, however, can contribute to antimicrobial resistance (AMR) and expose the foetus to drugs that might affect its development. Preventative behaviours are currently the best option to reduce incidences of UTIs and to avoid the use of antibiotics in pregnancy. The aim of this study was to explore women’s experiences of UTIs in pregnancy to develop an understanding of their concerns and to optimise and encourage behaviours that facilitate appropriate use of antibiotics.
Methods
An online pregnancy forum in the United Kingdom (UK) was used to collect data on women’s discussions of UTIs. A total of 202 individual threads generated by 675 different usernames were selected for analysis. The data was organised using NVivo 11® software and then analysed qualitatively using inductive thematic analysis.
Results
Women’s perceptions of UTIs and antibiotic use in pregnancy were driven by their pre-natal attachment to the foetus. UTIs were thought to be common and high risk in pregnancy, which meant that antibiotics were viewed as essential in the presence of suspected symptoms. The dominant view about antibiotics was that their use was safe and of little concern in pregnancy. Women reported an emotional reaction to developing a UTI. They coped by seeking information about behaviour change strategies to assist with recovery and through emotional support from the online forum.
Conclusions
Women face dual risks when they experience UTIs; the risk from the infection and the risk from antibiotic treatment. Pre-natal attachment to the foetus is highlighted in the decision making process. The focus is on the shorter term risk from UTIs while undermining the longer term risks from antibiotic use, especially the risk of AMR. A balanced view needs to be presented, and evidence-based infection prevention strategies should be promoted, to women to ensure appropriate antibiotic use in pregnancy, to address the global challenge of AMR
Decision-to-incision times and maternal and infant outcomes.
Journal ArticleOBJECTIVE: To measure decision-to-incision intervals and related maternal and neonatal outcomes in a cohort of women undergoing emergency cesarean deliveries at multiple university-based hospitals comprising the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. METHODS: All women undergoing a primary cesarean delivery at a Network center during a 2-year time span were prospectively ascertained. Emergency procedures were defined as those performed for umbilical cord prolapse, placental abruption, placenta previa with hemorrhage, nonreassuring fetal heart rate pattern, or uterine rupture. Detailed information regarding maternal and neonatal outcomes, including the interval from the decision time to perform cesarean delivery to the actual skin incision, was collected. RESULTS: Of the 11,481 primary cesarean deliveries, 2,808 were performed for an emergency indication. Of these, 1,814 (65%) began within 30 minutes of the decision to operate. Maternal complication rates, including endometritis, wound infection, and operative injury, were not related to the decision-to-incision interval. Measures of newborn compromise including umbilical artery pH less than 7 and intubation in the delivery room were significantly greater when the cesarean delivery was commenced within 30 minutes, likely attesting to the need for expedited delivery. Of the infants with indications for an emergency cesarean delivery who were delivered more than 30 minutes after the decision to operate, 95% did not experience a measure of newborn compromise. CONCLUSION: Approximately one third of primary cesarean deliveries performed for emergency indications are commenced more than 30 minutes after the decision to operate, and the majority were for nonreassuring heart rate tracings. In these cases, adverse neonatal outcomes were not increased. LEVEL OF EVIDENCE: II-2
Interphase chromosome positioning in in vitro porcine cells and ex vivo porcine tissues
Copyright @ 2012 The Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and 85 reproduction in any medium, provided the original author and source are credited. The article was made available through the Brunel University Open Access Publishing Fund.BACKGROUND: In interphase nuclei of a wide range of species chromosomes are organised into their own specific locations termed territories. These chromosome territories are non-randomly positioned in nuclei which is believed to be related to a spatial aspect of regulatory control over gene expression. In this study we have adopted the pig as a model in which to study interphase chromosome positioning and follows on from other studies from our group of using pig cells and tissues to study interphase genome re-positioning during differentiation. The pig is an important model organism both economically and as a closely related species to study human disease models. This is why great efforts have been made to accomplish the full genome sequence in the last decade. RESULTS: This study has positioned most of the porcine chromosomes in in vitro cultured adult and embryonic fibroblasts, early passage stromal derived mesenchymal stem cells and lymphocytes. The study is further expanded to position four chromosomes in ex vivo tissue derived from pig kidney, lung and brain. CONCLUSIONS: It was concluded that porcine chromosomes are also non-randomly positioned within interphase nuclei with few major differences in chromosome position in interphase nuclei between different cell and tissue types. There were also no differences between preferred nuclear location of chromosomes in in vitro cultured cells as compared to cells in tissue sections. Using a number of analyses to ascertain by what criteria porcine chromosomes were positioned in interphase nuclei; we found a correlation with DNA content.This study is partly supported by Sygen International PLC
The bashful and the boastful : prestigious leaders and social change in Mesolithic Societies
The creation and maintenance of influential leaders and authorities is one of the key themes of archaeological and historical enquiry. However the social dynamics of authorities and leaders in the Mesolithic remains a largely unexplored area of study. The role and influence of authorities can be remarkably different in different situations yet they exist in all societies and in almost all social contexts from playgrounds to parliaments. Here we explore the literature on the dynamics of authority creation, maintenance and contestation in egalitarian societies, and discuss the implications for our interpretation and understanding of the formation of authorities and leaders and changing social relationships within the Mesolithic
- …