4,176 research outputs found
Children with severe malnutrition: can those at highest risk of death be identified with the WHO protocol?
Background With strict adherence to international recommended treatment guidelines, the case fatality for severe malnutrition ought to be less than 5%. In African hospitals, fatality rates of 20% are common and are often attributed to poor training and faulty case management. Improving outcome will depend upon the identification of those at greatest risk and targeting limited health resources. We retrospectively examined the major risk factors associated with early (<48 h) and late in-hospital death in children with severe malnutrition with the aim of identifying admission features that could distinguish a high-risk group in relation to the World Health Organization (WHO) guidelines. Methods and Findings Of 920 children in the study, 176 (19%) died, with 59 (33%) deaths occurring within 48 h of admission. Bacteraemia complicated 27% of all deaths: 52% died before 48 h despite 85% in vitro antibiotic susceptibility of cultured organisms. The sensitivity, specificity, and likelihood ratio of the WHO-recommended “danger signs” (lethargy, hypothermia, or hypoglycaemia) to predict early mortality was 52%, 84%, and 3.4% (95% confidence interval [CI] = 2.2 to 5.1), respectively. In addition, four bedside features were associated with early case fatality: bradycardia, capillary refill time greater than 2 s, weak pulse volume, and impaired consciousness level; the presence of two or more features was associated with an odds ratio of 9.6 (95% CI = 4.8 to 19) for early fatality (p < 0.0001). Conversely, the group of children without any of these seven features, or signs of dehydration, severe acidosis, or electrolyte derangements, had a low fatality (7%). Conclusions Formal assessment of these features as emergency signs to improve triage and to rationalize manpower resources toward the high-risk groups is required. In addition, basic clinical research is necessary to identify and test appropriate supportive treatments
Synthetic magnetism for photon fluids
We develop a theory of artificial gauge fields in photon fluids for the cases
of both second-order and third-order optical nonlinearities. This applies to
weak excitations in the presence of pump fields carrying orbital angular
momentum, and is thus a type of Bogoliubov theory. The resulting artificial
gauge fields experienced by the weak excitations are an interesting
generalization of previous cases and reflect the PT-symmetry properties of the
underlying non-Hermitian Hamiltonian. We illustrate the observable consequences
of the resulting synthetic magnetic fields for examples involving both
second-order and third-order nonlinearities
Destination images of non-visitors
This article provides much needed understanding of destination images held by non-visitors. Recognizing the characteristics of non-visitor images and their formation is important in order to understand images more widely. This qualitative study assesses images of London. The views of three hundred people in the Czech Republic who have never visited London were obtained via an innovative open-ended research instrument. The study showed that non-visitors imagine destinations through comparisons with their own experiences of places. Findings indicate that images can be very persistent and that the first images formed of a destination endure over time. Although the research is based on people with no direct experience of London, the research highlights that a range of secondary ‘experiences’ influence image formation
Phenotypic effects of overexpression of the MMAC1 gene in prostate epithelial cells
The prostate cancer cell lines PC3 and LNCaP have been shown to lack expression of the tumour suppressor gene MMAC1/PTEN, in contrast to the immortalized non-tumorigenic epithelial lines PNT1a and PNT2. We have measured the effects of reintroduction of wild type (wt) and mutant MMAC1 genes on to these genetic backgrounds, using gene constructs expressing either wt MMAC1 or various mutants deficient in the dual specificity phosphatase domain of the protein. Over-expression of wild type PTEN protein induced cell shrinkage and rounding, but did not result in increased levels of classical apoptosis. Permanently transfected lines containing the MMAC1 gene could only be obtained from the PNT cells, as PTEN expression resulted in rapid loss of both tumour lines. In contrast, mutation of the phosphatase domain resulted in partial attenuation of the phenotypic effects of MMAC1 after transient transfection, and also allowed the derivation of permanent tumour cell lines containing the mutated MMAC1 gene. The results suggest that re-expression of wt PTEN is incompatible with survival of human prostate cancer cells in vitro, and that the full biological activity of this common tumour suppressor requires functions additional to the established protein and lipid phosphatase activities in epithelial systems. © 2000 Cancer Research Campaig
Rapid intravenous rehydration of children with acute gastroenteritis and dehydration: a systematic review and meta-analysis
Background: The World Health Organization (WHO) recommends rapid intravenous rehydration, using fluid volumes of 70-100mls/kg over 3–6 h, with some of the initial volume given rapidly as initial fluid boluses to treat hypovolaemic shock for children with acute gastroenteritis (AGE) and severe dehydration. The evidence supporting the safety and efficacy of rapid versus slower rehydration remains uncertain.Methods: We conducted a systematic review of randomised controlled trials (RCTs) on 11th of May 2017 comparing different rates of intravenous fluid therapy in children with AGE and moderate or severe dehydration, using standard search terms. Two authors independently assessed trial quality and extracted data. Non-RCTs and non-English articles were excluded. The primary endpoint was mortality and secondary endpoints included adverse events (safety) and treatment efficacy.Main results: Of the 1390 studies initially identified, 18 were assessed for eligibility. Of these, 3 studies (n = 464) fulfilled a priori criteria for inclusion; most studied children with moderate dehydration and none were conducted in resource-poor settings. Volumes and rates of fluid replacement varied from 20 to 60 ml/kg given over 1-2 h (fast) versus 2-4 h (slow). There was substantial heterogeneity in methodology between the studies with only one adjudicated to be of high quality. There were no deaths in any study. Safety endpoints only identified oedema (n = 6) and dysnatraemia (n = 2). Pooled analysis showed no significant difference between the rapid and slow intravenous rehydration groups for the proportion of treatment failures (N = 468): pooled RR 1.30 (95% CI: 0.87, 1.93) and the readmission rates (N = 439): pooled RR 1.39 (95% CI: 0.68, 2.85).Conclusions: Despite wide implementation of WHO Plan C guideline for severe AGE, we found no clinical evaluation in resource-limited settings, and only limited evaluation of the rate and volume of rehydration in other parts of the world. Recent concerns over aggressive fluid expansion warrants further research to inform guidelines on rates of intravenous rehydration therapy for severe AG
In vitro modelling of epithelial and stromal interactions in non-malignant and malignant prostates
To study the effects of stromal epithelial cell interactions on prostate cancer metastasis, we have used primary human prostatic stromal cells derived from malignant and non-malignant tissues and established epithelial cell lines from normal (PNT1a and PNT2-C2) and tumour (PC-3, DU145 and LNCaP) origins. The effects of stromal cells on epithelial cell growth were studied in direct and indirect (using culture inserts) co-culture and by exposure to stromal cell-conditioned medium (assessed by MTT assay). The influence of stromal cells on epithelial cell invasion was measured using matrigel invasion chambers and on epithelial cell motility using time lapse microscopy. Results indicated that epithelial cell line growth was similarly unaffected or inhibited by stromal cells derived from malignant (n = 8) or non-malignant tissue (n = 8). In contrast, PNT2-C2 and PC-3 cells were found to be the least and the most invasive and motile epithelia respectively. Stromal cultures enhanced the invasion of both epithelial cells, but no differences were observed between the use of malignant and non-malignant tissues. All stromal cultures modestly stimulated PNT2-C2 motility but displayed a greater stimulation of PC-3 cell motility, while stromal cells derived from malignant tissue stimulated PNT2-C2 and PC-3 cell motility more than stromal cultures from non-malignant tissues. © 2000 Cancer Research Campaig
A Tale of Two Surfers: Joy and Wellbeing in Mature Participants
Within larger concern over wellbeing at a global level, there is growing interest in the role that sport can play in developing positive wellbeing with a focus on young people. Lifestyle sports that people participate in for pleasure rather than competition are likely to offer opportunity to develop wellbeing but research on them neglects middle aged participants. This article redresses this oversight by focusing on two surfers, with one male and one female, in their forties to explore the role that surfing plays in their lives and its contribution to their wellbeing. Using a narrative inquiry approach it explores the place of surfing in their lives over three decades to identify how its meaning changed as they matured and how it offered a highly effective coping mechanism for dealing with life’s stresses and pressures
Incidence and clinical characteristics of group A rotavirus infections among children admitted to hospital in Kilifi, Kenya
Background
Rotavirus, predominantly of group A, is a major cause of severe diarrhoea worldwide, with
the greatest burden falling on young children living in less-developed countries. Vaccines
directed against this virus have shown promise in recent trials, and are undergoing
effectiveness evaluation in sub-Saharan Africa. In this region limited childhood data are
available on the incidence and clinical characteristics of severe group A rotavirus disease.
Advocacy for vaccine intervention and interpretation of effectiveness following implementation
will benefit from accurate base-line estimates of the incidence and severity of rotavirus
paediatric admissions in relevant populations. The study objective was to accurately define the
incidence and severity of group A rotavirus disease in a resource-poor setting necessary to
make informed decisions on the need for vaccine prevention.
Methods and Findings
Between 2002 and 2004 we conducted prospective surveillance for group A rotavirus
infection at Kilifi District Hospital in coastal Kenya. Children < 13 y of age were eligible as
"cases" if admitted with diarrhoea, and "controls" if admitted without diarrhoea. We calculated
the incidence of hospital admission with group A rotavirus using data from a demographic
surveillance study of 220,000 people in Kilifi District. Of 15,347 childhood admissions 3,296
(22%) had diarrhoea, 2,039 were tested for group A rotavirus antigen and, of these, 588 (29%)
were positive. 372 (63%) rotavirus-positive cases were infants. Of 620 controls 19 (3.1%, 95%
confidence interval [CI] 1.9–4.7) were rotavirus positive. The annual incidence (per 100,000
children) of rotavirus-positive admissions was 1,431 (95% CI 1,275–1,600) in infants and 478
(437–521) in under-5-y-olds, and highest proximal to the hospital. Compared to children with
rotavirus-negative diarrhoea, rotavirus-positive cases were less likely to have coexisting
illnesses and more likely to have acidosis (46% versus 17%) and severe electrolyte imbalance
except hyponatraemia. In-hospital case fatality was 2% among rotavirus-positive and 9%
among rotavirus-negative children.
Conclusions
In Kilifi > 2% of children are admitted to hospital with group A rotavirus diarrhoea in the first
5 y of life. This translates into over 28,000 vaccine-preventable hospitalisations per year across
Kenya, and is likely to be a considerable underestimate. Group A rotavirus diarrhoea is
associated with acute life-threatening metabolic derangement in otherwise healthy children.
Although mortality is low in this clinical research setting this may not be generally true in
African hospitals lacking rapid and appropriate management
Population pharmacokinetics of a single daily intramuscular dose of gentamicin in children with severe malnutrition
Article published in Journal of Antimicrobial ChemotherapyObjectives: The World Health Organization recommends that all children admitted with severe
malnutrition should routinely receive parenteral ampicillin and gentamicin; despite this, mortality
remains high. Since this population group is at risk of altered volume of distribution, we aimed to
study the population pharmacokinetics of once daily gentamicin (7.5 mg/kg) in children with severe
malnutrition and to evaluate clinical factors affecting pharmacokinetic parameters.
Methods: Thirty-four children aged 0.5–10 years were studied. One hundred and thirty-two gentamicin
concentrations (median of four per patient), drawn 0.4–24.6 h after administration of the intramuscular
dose, were analysed. The data were fitted by a two-compartment model using the population package
NONMEMw.
Results: Gentamicin was rapidly absorbed and all concentrations measured within the first 2 h after
administration were >8 mg/L (indicating that satisfactory peak concentrations were achieved). Ninetyeight
percent of samples measured more than 20 h after the dose were <1 mg/L. The best model
included weight, and it was found that high base deficit, high creatinine concentration and low temperature
(all markers of hypovolaemic shock) reduced clearance (CL/F). Weight influenced volume of the
central (V1/F) and peripheral (V2/F) compartments, and high base deficit reduced V2/F and intercompartmental
CL (Q/F). Interindividual variability in CL was 26%, in V1/F 33% and in V2/F and Q/F was
52%. Individual estimates of CL/F ranged from 0.02 to 0.16 (median 0.10) L/h/kg and those of Vss/F
from 0.26 to 1.31 (median 0.67) L/kg. Initial half-lives had a median of 1.4 h and elimination half-lives
and a median of 14.9 h. Excessive concentrations were observed in one patient who had signs of renal
impairment and shock.
Conclusions: Although a daily dose of 7.5 mg/kg achieves satisfactory gentamicin concentrations in
the majority of patients, patients with renal impairment and shock may be at risk of accumulation with
24 hourly dosing. Further studies of gentamicin pharmacokinetics in this group are now needed to
inform future international guideline recommendations
- …