34 research outputs found
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Mycobacterium abscessus - an uncommon, but important cause of peritoneal dialysis-associated peritonitis - case report and literature review.
BACKGROUND: Peritoneal dialysis (PD) is a form of therapy for end-stage kidney disease (ESKD), and peritonitis is a known complication. Mycobacterium (M) species associated peritonitis in PD patients is uncommon. Our experience of managing PD associated peritonitis caused by M abscessus in a middle-aged man with ESKD due to focal segmental glomerulosclerosis is shared in this article with a review of the literature on this condition. CASE PRESENTATION: A 49-year old man presented to our unit with symptoms of peritonitis and cloudy PD effluent. Initial analysis of PD fluid showed Gram stain was negative, with no organism grown. Empirical PD peritonitis treatment with intra-peritoneal antibiotics did not improve his symptoms and he required intravenous antibiotics, PD catheter removal and a switch to haemodialysis. Cultures of the PD fluid later grew M abscessus, and the antibiotic regimen was changed appropriately, leading to clinical improvement. CONCLUSION: M abscessus associated peritonitis in PD patients is rare. It needs to be borne in mind when clinical improvement is not seen with standard broad-spectrum antibiotics, especially in situations where the PD fluid is initially deemed to be culture negative. PD fluid samples should be sent for acid-fast bacillus and if detected, should be further analysed with genome-wide sequencing to confirm the species of the Mycobacterium. Prompt removal of the catheter with peritoneal washout is critical for clinical improvement
Susskind's Challenge to the Hartle-Hawking No-Boundary Proposal and Possible Resolutions
Given the observed cosmic acceleration, Leonard Susskind has presented the
following argument against the Hartle-Hawking no-boundary proposal for the
quantum state of the universe: It should most likely lead to a nearly empty
large de Sitter universe, rather than to early rapid inflation. Even if one
adds the condition of observers, they are most likely to form by quantum
fluctuations in de Sitter and therefore not see the structure that we observe.
Here I present my own amplified version of this argument and consider possible
resolutions, one of which seems to imply that inflation expands the universe to
be larger than 10^{10^{10^{122}}} Mpc.Comment: 24 pages, LaTeX, 8 references added and a distinction between Linde's
and Vilenkin's tunneling proposal
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Ariel – a window to the origin of life on early earth?
Is there life beyond Earth? An ideal research program would first ascertain how life on Earth began and then use this as a blueprint for its existence elsewhere. But the origin of life on Earth is still not understood, what then could be the way forward? Upcoming observations of terrestrial exoplanets provide a unique opportunity for answering this fundamental question through the study of other planetary systems. If we are able to see how physical and chemical environments similar to the early Earth evolve we open a window into our own Hadean eon, despite all information from this time being long lost from our planet’s geological record. A careful investigation of the chemistry expected on young exoplanets is therefore necessary, and the preparation of reference materials for spectroscopic observations is of paramount importance. In particular, the deduction of chemical markers identifying specific processes and features in exoplanetary environments, ideally “uniquely”. For instance, prebiotic feedstock molecules, in the form of aerosols and vapours, could be observed in transmission spectra in the near future whilst their surface deposits could be observed from reflectance spectra. The same detection methods also promise to identify particular intermediates of chemical and physical processes known to be prebiotically plausible. Is Ariel truly able to open a window to the past and answer questions concerning the origin of life on our planet and the universe? In this paper, we discuss aspects of prebiotic chemistry that will help in formulating future observational and data interpretation strategies for the Ariel mission. This paper is intended to open a discussion and motivate future detailed laboratory studies of prebiotic processes on young exoplanets and their chemical signatures
'Communicate to vaccinate' (COMMVAC). building evidence for improving communication about childhood vaccinations in low- and middle-income countries: protocol for a programme of research
ABSTRACT: BACKGROUND: Effective provider-parent communication can improve childhood vaccination uptake and strengthen immunisation services in low- and middle-income countries (LMICs). Building capacity to improve communication strategies has been neglected. Rigorous research exists but is not readily found or applicable to LMICs, making it difficult for policy makers to use it to inform vaccination policies and practice. The aim of this project is to build research knowledge and capacity to use evidence-based strategies for improving communication about childhood vaccinations with parents and communities in LMICs. Methods and design This project is a mixed methods study with six sub-studies. In sub-study one, we will develop a systematic map of provider-parent communication interventions for childhood vaccinations by screening and extracting data from relevant literature. This map will inform sub-study two, in which we will develop a taxonomy of interventions to improve provider-parent communication around childhood vaccination. In sub-study three, the taxonomy will be populated with trial citations to create an evidence map, which will also identify how evidence is linked to communication barriers regarding vaccination. In the project's fourth sub-study, we will present the interventions map, taxonomy, and evidence map to international stakeholders to identify high-priority topics for systematic reviews of interventions to improve parent-provider communication for childhood vaccination. We will produce systematic reviews of the effects of high-priority interventions in the fifth sub-study. In the sixth and final sub-study of the project, evidence from the systematic reviews will be translated into accessible formats and messages for dissemination to LMICs. DISCUSSION: This project combines evidence mapping, conceptual and taxonomy development, priority setting, systematic reviews, and knowledge transfer. It will build and share concepts, terms, evidence, and resources to aid the development of communication strategies for effective vaccination programmes in LMIC
Community perceptions of malaria and vaccines in the South Coast and Busia regions of Kenya
<p>Abstract</p> <p>Background</p> <p>Malaria is a leading cause of morbidity and mortality in children younger than 5 years in Kenya. Within the context of planning for a vaccine to be used alongside existing malaria control methods, this study explores sociocultural and health communications issues among individuals who are responsible for or influence decisions on childhood vaccination at the community level.</p> <p>Methods</p> <p>This qualitative study was conducted in two malaria-endemic regions of Kenya--South Coast and Busia. Participant selection was purposive and criterion based. A total of 20 focus group discussions, 22 in-depth interviews, and 18 exit interviews were conducted.</p> <p>Results</p> <p>Participants understand that malaria is a serious problem that no single tool can defeat. Communities would welcome a malaria vaccine, although they would have questions and concerns about the intervention. While support for local child immunization programs exists, limited understanding about vaccines and what they do is evident among younger and older people, particularly men. Even as health care providers are frustrated when parents do not have their children vaccinated, some parents have concerns about access to and the quality of vaccination services. Some women, including older mothers and those less economically privileged, see themselves as the focus of health workers' negative comments associated with either their parenting choices or their children's appearance. In general, parents and caregivers weigh several factors--such as personal opportunity costs, resource constraints, and perceived benefits--when deciding whether or not to have their children vaccinated, and the decision often is influenced by a network of people, including community leaders and health workers.</p> <p>Conclusions</p> <p>The study raises issues that should inform a communications strategy and guide policy decisions within Kenya on eventual malaria vaccine introduction. Unlike the current practice, where health education on child welfare and immunization focuses on women, the communications strategy should equally target men and women in ways that are appropriate for each gender. It should involve influential community members and provide needed information and reassurances about immunization. Efforts also should be made to address concerns about the quality of immunization services--including health workers' interpersonal communication skills.</p
One size does not fit all: local determinants of measles vaccination in four districts of Pakistan
Common factors are associated with vaccination. However, despite common factors the pattern of variables related to measles vaccination differs between and within districts. In this study children were more likely to receive measles vaccination if their mother had any formal education, if she knew at least one vaccine preventable disease, and if she had not heard of any bad effects of vaccination. In rural areas, living within 5 km of a vaccination facility or in a community visited by a vaccination team were factors associated with vaccination, as was the mother receiving information about vaccinations
Immunoglobulin, glucocorticoid, or combination therapy for multisystem inflammatory syndrome in children: a propensity-weighted cohort study
Background: Multisystem inflammatory syndrome in children (MIS-C), a hyperinflammatory condition associated with SARS-CoV-2 infection, has emerged as a serious illness in children worldwide. Immunoglobulin or glucocorticoids, or both, are currently recommended treatments. Methods: The Best Available Treatment Study evaluated immunomodulatory treatments for MIS-C in an international observational cohort. Analysis of the first 614 patients was previously reported. In this propensity-weighted cohort study, clinical and outcome data from children with suspected or proven MIS-C were collected onto a web-based Research Electronic Data Capture database. After excluding neonates and incomplete or duplicate records, inverse probability weighting was used to compare primary treatments with intravenous immunoglobulin, intravenous immunoglobulin plus glucocorticoids, or glucocorticoids alone, using intravenous immunoglobulin as the reference treatment. Primary outcomes were a composite of inotropic or ventilator support from the second day after treatment initiation, or death, and time to improvement on an ordinal clinical severity scale. Secondary outcomes included treatment escalation, clinical deterioration, fever, and coronary artery aneurysm occurrence and resolution. This study is registered with the ISRCTN registry, ISRCTN69546370. Findings: We enrolled 2101 children (aged 0 months to 19 years) with clinically diagnosed MIS-C from 39 countries between June 14, 2020, and April 25, 2022, and, following exclusions, 2009 patients were included for analysis (median age 8·0 years [IQR 4·2–11·4], 1191 [59·3%] male and 818 [40·7%] female, and 825 [41·1%] White). 680 (33·8%) patients received primary treatment with intravenous immunoglobulin, 698 (34·7%) with intravenous immunoglobulin plus glucocorticoids, 487 (24·2%) with glucocorticoids alone; 59 (2·9%) patients received other combinations, including biologicals, and 85 (4·2%) patients received no immunomodulators. There were no significant differences between treatments for primary outcomes for the 1586 patients with complete baseline and outcome data that were considered for primary analysis. Adjusted odds ratios for ventilation, inotropic support, or death were 1·09 (95% CI 0·75–1·58; corrected p value=1·00) for intravenous immunoglobulin plus glucocorticoids and 0·93 (0·58–1·47; corrected p value=1·00) for glucocorticoids alone, versus intravenous immunoglobulin alone. Adjusted average hazard ratios for time to improvement were 1·04 (95% CI 0·91–1·20; corrected p value=1·00) for intravenous immunoglobulin plus glucocorticoids, and 0·84 (0·70–1·00; corrected p value=0·22) for glucocorticoids alone, versus intravenous immunoglobulin alone. Treatment escalation was less frequent for intravenous immunoglobulin plus glucocorticoids (OR 0·15 [95% CI 0·11–0·20]; p<0·0001) and glucocorticoids alone (0·68 [0·50–0·93]; p=0·014) versus intravenous immunoglobulin alone. Persistent fever (from day 2 onward) was less common with intravenous immunoglobulin plus glucocorticoids compared with either intravenous immunoglobulin alone (OR 0·50 [95% CI 0·38–0·67]; p<0·0001) or glucocorticoids alone (0·63 [0·45–0·88]; p=0·0058). Coronary artery aneurysm occurrence and resolution did not differ significantly between treatment groups. Interpretation: Recovery rates, including occurrence and resolution of coronary artery aneurysms, were similar for primary treatment with intravenous immunoglobulin when compared to glucocorticoids or intravenous immunoglobulin plus glucocorticoids. Initial treatment with glucocorticoids appears to be a safe alternative to immunoglobulin or combined therapy, and might be advantageous in view of the cost and limited availability of intravenous immunoglobulin in many countries. Funding: Imperial College London, the European Union's Horizon 2020, Wellcome Trust, the Medical Research Foundation, UK National Institute for Health and Care Research, and National Institutes of Health
Mars: new insights and unresolved questions
Mars exploration motivates the search for extraterrestrial life, the development of space technologies, and the design of human missions and habitations. Here, we seek new insights and pose unresolved questions relating to the natural history of Mars, habitability, robotic and human exploration, planetary protection, and the impacts on human society. Key observations
and findings include:
– high escape rates of early Mars’ atmosphere, including loss of water, impact present-day habitability;
– putative fossils on Mars will likely be ambiguous biomarkers for life;
– microbial contamination resulting from human habitation is unavoidable; and
– based on Mars’ current planetary protection category, robotic payload(s) should characterize the local martian environment for any life-forms prior to human habitation.Some of the outstanding questions are:– which interpretation of the hemispheric dichotomy of the planet is correct;
– to what degree did deep-penetrating faults transport subsurface liquids to Mars’ surface;
– in what abundance are carbonates formed by atmospheric processes;
– what properties of martian meteorites could be used to constrain their source locations;
– the origin(s) of organic macromolecules;
– was/is Mars inhabited;
– how can missions designed to uncover microbial activity in the subsurface eliminate potential false positives caused by microbial contaminants from Earth;
– how can we ensure that humans and microbes form a stable and benign biosphere; and
– should humans relate to putative extraterrestrial life from a biocentric viewpoint (preservation of all biology), or anthropocentric viewpoint of expanding habitation of space?Studies of Mars’ evolution can shed light on the habitability of extrasolar planets. In addition,
Mars exploration can drive future policy developments and confirm (or put into question) the
feasibility and/or extent of human habitability of space