114 research outputs found
Genetic Engineering of Trypanosoma (Dutonella) vivax and In Vitro Differentiation under Axenic Conditions
Trypanosoma vivax is one of the most common parasites responsible for animal trypanosomosis, and although this disease is widespread in Africa and Latin America, very few studies have been conducted on the parasite's biology. This is in part due to the fact that no reproducible experimental methods had been developed to maintain the different evolutive forms of this trypanosome under laboratory conditions. Appropriate protocols were developed in the 1990s for the axenic maintenance of three major animal Trypanosoma species: T. b. brucei, T. congolense and T. vivax. These pioneer studies rapidly led to the successful genetic manipulation of T. b. brucei and T. congolense. Advances were made in the understanding of these parasites' biology and virulence, and new drug targets were identified. By contrast, challenging in vitro conditions have been developed for T. vivax in the past, and this per se has contributed to defer both its genetic manipulation and subsequent gene function studies. Here we report on the optimization of non-infective T. vivax epimastigote axenic cultures and on the process of parasite in vitro differentiation into metacyclic infective forms. We have also constructed the first T. vivax specific expression vector that drives constitutive expression of the luciferase reporter gene. This vector was then used to establish and optimize epimastigote transfection. We then developed highly reproducible conditions that can be used to obtain and select stably transfected mutants that continue metacyclogenesis and are infectious in immunocompetent rodents
The origins of the trypanosome genome strains Trypanosoma brucei brucei TREU 927, T. b. gambiense DAL 972, T. vivax Y486 and T. congolense IL3000
The genomes of several tsetse-transmitted African trypanosomes (Trypanosoma brucei brucei, T. b. gambiense, T. vivax, T. congolense) have been sequenced and are available to search online. The trypanosome strains chosen for the genome sequencing projects were selected because they had been well characterised in the laboratory, but all were isolated several decades ago. The purpose of this short review is to provide some background information on the origins and biological characterisation of these strains as a source of reference for future users of the genome data. With high throughput sequencing of many more trypanosome genomes in prospect, it is important to understand the phylogenetic relationships of the genome strains
Short and long term treatment of asthma with intravenous nutrients
BACKGROUND: Asthma is an increasing problem in this country and others. Although medications for the treatment of asthma abound and are improving, there are inherent risks and side effects with all of them. Intravenous magnesium has been employed in the treatment of acute asthma, but its use has not become universal, nor has it been studied for the treatment of chronic asthma. It is known to be a safe drug with minimal side effects. In this study, the author investigates the use of magnesium and other nutrients in the treatment of both acute and chronic asthma. METHODS: In this non-blinded outcome study, following informed consent, forty-three (43) randomly selected volunteer patients with both acute and chronic asthma were treated with IV infusions described herein. All patients were observed with spirometry 10 minutes post-infusion; two sub-groups of patients were also observed after multiple infusions over a short period of time (less than one month) and a longer period of time (average 5.8 months). Pulmonary function was analyzed by spirometric testing with pre- and post-infusion spirometric measurements with the pre/post group. For longer term (Trend) patients, baseline spirometry measurements were compared to spirometry measurements after patients had received multiple infusions over a period of time. Eight (8) patients were measured for both pre/post and Trend data. RESULTS: The 38 pre-infusion/post-infusion patients with acute and chronic asthma demonstrated an overall average improvement (percentage improvement in percent predicted) of 45%. The 13 patients measured for improvement over time (Trend data, average duration 5.82 months), demonstrated an overall average improvement (percentage improvement in percent predicted) of 57%. Of the 13 patients in the multiple infusion group, 9 patients who received longer-term therapy (average duration of 12.58 months) for chronic asthma demonstrated an overall average improvement of 95% (percentage improvement in percent predicted). CONCLUSION: The use of intravenous treatment with multiple nutrients, including magnesium, for acute and chronic asthma may be of considerable benefit. Pulmonary function improved progressively the longer patients received treatment
The Prevalence and Psychopathological Correlates of Sibling Bullying in Children with and without Autism Spectrum Disorder
Using data from a prospective population based study, the prevalence and psychopathological correlates of sibling bullying in children with and without autism spectrum disorder (ASD) were estimated. There were 475 children with ASD and 13,702 children without ASD aged 11 years. Children with ASD were more likely to be bullied by their siblings compared to those without ASD. They were also more likely than those without ASD to both bully and be bullied by their siblings, which was associated with lower prosocial skills as well as more internalizing and externalizing problems compared to those not involved in any sibling bullying. Interventions to improve social and emotional outcomes in children with ASD should focus on both the affected and the unaffected sibling
School's out: what are urban children doing? The Summer Activity Study of Somerville Youth (SASSY)
Background:
Research indicates that in the United States, children experience healthier BMI and fitness levels during school vs. summer, but research is limited. The primary goal of this pilot study was to assess where children spend their time during the months that school is not in session and to learn about the different types of activities they engage in within different care settings. A secondary goal of this pilot study was to learn what children eat during the summer months.
Methods:
A nine-week summer study of 57 parents of second and third grade students was conducted in an economically, racial/ethnically and linguistically diverse US urban city. Weekly telephone interviews queried time and activities spent on/in 1) the main caregiver’s care 2) someone else’s care 3) vacation 4) and camp. Activities were categorised as sedentary, light, moderate, or vigorous (0-3 scale). For each child, a mean activity level was calculated and weighted for proportion of time spent in each care situation, yielding a weighted activity index. On the last phone call, parents answered questions about their child’s diet over the summer. Two post-study focus groups were conducted to help interpret findings from the weekly activity interviews.
Results:
The mean activity index was 1.05 ± 0.32 and differed between gender (p = 0.07), education (p = 0.08) and primary language spoken in the household (p = 0.01). Children who spent a greater percentage of time in parent care had on average a lower activity index (β = -0.004, p = 0.01) while children who spent a greater percentage of time in camp had a higher activity index (β = 0.004, p = 0.03). When stratified into type of camp, percentage of time spent in active camp was also positively associated with mean activity index (β = 0.005, p =\u3c 0.001). With regards to diet, after adjusting for maternal education, children who attended less than five weeks of camp were four times more likely to eat their meals in front of the TV often/almost all of the time (OR = 4.0, 95%CI 1.0-16.2, p \u3c 0.06).
Conclusions:
Summer activities and some dietary behaviours are influenced by situation of care and sociodemographic characteristics. In particular, children who spend a greater proportion of time in structured environments appear to be more active. We believe that this pilot study is an important first step in our understanding of what children do during the summer months
High-resolution analysis of copy number alterations and associated expression changes in ovarian tumors
<p>Abstract</p> <p>Background</p> <p>DNA copy number alterations are frequently observed in ovarian cancer, but it remains a challenge to identify the most relevant alterations and the specific causal genes in those regions.</p> <p>Methods</p> <p>We obtained high-resolution 500K SNP array data for 52 ovarian tumors and identified the most statistically significant minimal genomic regions with the most prevalent and highest-level copy number alterations (recurrent CNAs). Within a region of recurrent CNA, comparison of expression levels in tumors with a given CNA to tumors lacking that CNA and to whole normal ovary samples was used to select genes with CNA-specific expression patterns. A public expression array data set of laser capture micro-dissected (LCM) non-malignant fallopian tube epithelia and LCM ovarian serous adenocarcinoma was used to evaluate the effect of cell-type mixture biases.</p> <p>Results</p> <p>Fourteen recurrent deletions were detected on chromosomes 4, 6, 9, 12, 13, 15, 16, 17, 18, 22 and most prevalently on X and 8. Copy number and expression data suggest several apoptosis mediators as candidate drivers of the 8p deletions. Sixteen recurrent gains were identified on chromosomes 1, 2, 3, 5, 8, 10, 12, 15, 17, 19, and 20, with the most prevalent gains localized to 8q and 3q. Within the 8q amplicon, <it>PVT1</it>, but not <it>MYC</it>, was strongly over-expressed relative to tumors lacking this CNA and showed over-expression relative to normal ovary. Likewise, the cell polarity regulators <it>PRKCI </it>and <it>ECT2 </it>were identified as putative drivers of two distinct amplicons on 3q. Co-occurrence analyses suggested potential synergistic or antagonistic relationships between recurrent CNAs. Genes within regions of recurrent CNA showed an enrichment of Cancer Census genes, particularly when filtered for CNA-specific expression.</p> <p>Conclusion</p> <p>These analyses provide detailed views of ovarian cancer genomic changes and highlight the benefits of using multiple reference sample types for the evaluation of CNA-specific expression changes.</p
Assessing the impact of prescribed medicines on health outcomes
This paper reviews methods that can be used to assess the impact of medicine use on population health outcomes. In the absence of a gold standard, we argue that a convergence of evidence from different types of studies using multiple methods of independent imperfection provides the best bases for attributing improvements in health outcomes to the use of medicines. The major requirements are: good evidence that a safe and effective medicine is being appropriately prescribed; covariation between medicine use and improved health outcomes; and being able to discount alternative explanations of the covariation (via covariate adjustment, propensity analyses and sensitivity analyses), so that medicine use is the most plausible explanation of the improved health outcomes. The strongest possible evidence would be provided by the coherence of the following types of evidence: (1) individual linked data showing that patients are prescribed the medicine, there are reasonable levels of patient compliance, and there is a relationship between medicine use and health improvements that is not explained by other factors; (2) ecological evidence of improvements in these health outcomes in the population in which the medicine is used. Confidence in these inferences would be increased by: the replication of these results in comparable countries and consistent trends in population vital statistics in countries that have introduced the medicine; and epidemiological modelling indicating that changes observed in population health outcomes are plausible given the epidemiology of the condition being treated
Parents' psychological adjustment in families of children with Spina Bifida: a meta-analysis
BACKGROUND: Spina Bifida (SB) is the second most common birth defect worldwide. Since the chances of survival in children with severe SB-forms have increased, medical care has shifted its emphasis from life-saving interventions to fostering the quality of life for these children and their families. Little is known, however, about the impact of SB on family adjustment. Reviewers have struggled to synthesize the few contradictory studies available. In this systematic review a new attempt was made to summarize the findings by using meta-analysis and by delimiting the scope of review to one concept of family adjustment: Parents' psychological adjustment. The questions addressed were: (a) do parents of children with SB have more psychological distress than controls? (b) do mothers and fathers differ? and (c) which factors correlate with variations in psychological adjustment? METHODS: PsycInfo, Medline, and reference lists were scanned. Thirty-three relevant studies were identified of which 15 were eligible for meta-analysis. RESULTS: SB had a negative medium-large effect on parents' psychological adjustment. The effect was more heterogeneous for mothers than for fathers. In the reviewed studies child factors (age, conduct problems, emotional problems, and mental retardation), parent factors (SES, hope, appraised stress, coping, and parenting competence), family factors (family income, partner relationship, and family climate), and environmental factors (social support) were found to be associated with variations in parents' psychological adjustment. CONCLUSION: Meta-analysis proved to be helpful in organizing studies. Clinical implications indicate a need to be especially alert to psychological suffering in mothers of children with SB. Future research should increase sample sizes through multi-center collaborations
Ischaemic conditioning and targeting reperfusion injury: a 30 year voyage of discovery
To commemorate the auspicious occasion of the 30th anniversary of IPC, leading pioneers in the field of cardioprotection gathered in Barcelona in May 2016 to review and discuss the history of IPC, its evolution to IPost and RIC, myocardial reperfusion injury as a therapeutic target, and future targets and strategies for cardioprotection. This article provides an overview of the major topics discussed at this special meeting and underscores the huge importance and impact, the discovery of IPC has made in the field of cardiovascular research
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