Potential bronchoconstrictor stimuli in acid fog.

Acid fog is complex and contains multiple stimuli that may be capable of inducing bronchoconstriction. These stimuli include sulfuric and niric acids, the principal inorganic acids present; sulfites, formed in the atmosphere as a reaction product of sulfur dioxide and water droplets; fog water itself, a hypoosmolar aerosol; the organic acid hydroxymethanesulfonate, the bisulfite adduct of formaldehyde; and gaseous pollutants, e.g., sulfur dioxide, oxides of nitrogen, ozone. Given this complexity, evaluation of the respiratory health effects of naturally occurring acid fog requires assessment of the bronchoconstrictor potency of each component stimulus and possible interactions among these stimuli. We summarize the results of three studies that involve characterization of the bronchoconstrictor potency of acid fog stimuli and/or their interaction in subjects with asthma. The results of the first study indicate that titratable acidity appears to be a more important stimulus to bronchoconstriction than is pH. The results of the second study demonstrate that sulfite species are capable of inducing bronchoconstriction, especially when inhaled at acid pH. The results of the third study suggest that acidity can potentiate hypoosmolar fog-induced bronchoconstriction

Ocean acidification impairs vermetid reef recruitment.

Vermetids form reefs in sub-tropical and warm-temperate waters that protect coasts from erosion, regulate sediment transport and accumulation, serve as carbon sinks and provide habitat for other species. The gastropods that form these reefs brood encapsulated larvae; they are threatened by rapid environmental changes since their ability to disperse is very limited. We used transplant experiments along a natural CO2 gradient to assess ocean acidification effects on the reef-building gastropod Dendropoma petraeum. We found that although D. petraeum were able to reproduce and brood at elevated levels of CO2, recruitment success was adversely affected. Long-term exposure to acidified conditions predicted for the year 2100 and beyond caused shell dissolution and a significant increase in shell Mg content. Unless CO2 emissions are reduced and conservation measures taken, our results suggest these reefs are in danger of extinction within this century, with significant ecological and socioeconomic ramifications for coastal systems

Use of Short Tandem Repeat Sequences to Study Mycobacterium leprae in Leprosy Patients in Malawi and India

Molecular typing has provided an important tool for studies of many pathogens. Such methods could be particularly useful in studies of leprosy, given the many outstanding questions about the pathogenesis and epidemiology of this disease. The approach is particularly difficult with leprosy, however, because of the genetic homogeneity of M. leprae and our inability to culture it. This paper describes molecular epidemiological studies carried out on leprosy patients in Malawi and in India, using short tandem repeat sequences (STRS) as markers of M. leprae strains. It reveals evidence for continuous changes in these markers within individual patients over time, and for selection of different STRS-defined strains between different tissues (skin and nerve) in the same patient. Comparisons between patients collected under different circumstances reveal the uses and limitations of the approach—STRS analysis may in some circumstances provide a means to trace short transmission chains, but it does not provide a robust tool for distinguishing between relapse and reinfection. This encourages further work to identify genetic markers with different stability characteristics for incorporation into epidemiological studies of leprosy

From regional pulse vaccination to global disease eradication: insights from a mathematical model of Poliomyelitis

Mass-vaccination campaigns are an important strategy in the global fight against poliomyelitis and measles. The large-scale logistics required for these mass immunisation campaigns magnifies the need for research into the effectiveness and optimal deployment of pulse vaccination. In order to better understand this control strategy, we propose a mathematical model accounting for the disease dynamics in connected regions, incorporating seasonality, environmental reservoirs and independent periodic pulse vaccination schedules in each region. The effective reproduction number, $R_e$, is defined and proved to be a global threshold for persistence of the disease. Analytical and numerical calculations show the importance of synchronising the pulse vaccinations in connected regions and the timing of the pulses with respect to the pathogen circulation seasonality. Our results indicate that it may be crucial for mass-vaccination programs, such as national immunisation days, to be synchronised across different regions. In addition, simulations show that a migration imbalance can increase $R_e$ and alter how pulse vaccination should be optimally distributed among the patches, similar to results found with constant-rate vaccination. Furthermore, contrary to the case of constant-rate vaccination, the fraction of environmental transmission affects the value of $R_e$ when pulse vaccination is present.Comment: Added section 6.1, made other revisions, changed titl

Pathogenesis and treatment of oral candidosis

Oral infections caused by yeast of the genus Candida and particularly Candida albicans (oral candidoses) have been recognised throughout recorded history. However, since the 1980s a clear surge of interest and associated research into these infections have occurred. This has largely been due to an increased incidence of oral candidosis over this period, primarily because of the escalation in HIV-infection and the AIDS epidemic. In addition, changes in medical practice leading to a greater use of invasive clinical procedures and a more widespread use of immunosuppressive therapies have also contributed to the problem. Whilst oral candidosis has previously been considered to be a disease mainly of the elderly and very young, its occurrence throughout the general population is now recognised. Candida are true ‘opportunistic pathogens’ and only instigate oral infection when there is an underlying predisposing condition in the host. Treatment of these infections has continued (and in some regards continues) to be problematic because of the potential toxicity of traditional antifungal agents against host cells. The problem has been compounded by the emergence of Candida species other than C. albicans that have inherent resistance against traditional antifungals. The aim of this review is to give the reader a contemporary overview of oral candidosis, the organisms involved, and the management strategies that are currently employed or could be utilised in the future

BCG Revaccination Does Not Protect Against Leprosy in the Brazilian Amazon: A Cluster Randomised Trial

BCG is a vaccine developed and used to protect against tuberculosis, but it can also protect against leprosy. In Brazil, children receive BCG at birth, and since 1996 a trial has been conducted to find out if a second dose of BCG administered to schoolchildren gives additional protection against tuberculosis. We use this trial to find out if such vaccination protects against leprosy. The trial was conducted in the Brazilian Amazon, involving almost 100,000 children aged 7–14 years who had received neonatal BCG. Half of them received a second dose of BCG at school, and the other half did not. We followed the children for 6 years and observed that there were as many new cases of leprosy in the vaccinated children as in the unvaccinated children. Therefore, we concluded that a second dose of BCG given at school age in the Brazilian Amazon offers no additional protection against leprosy

Quality of care in elder emergency department patients with pneumonia: a prospective cohort study

<p>Abstract</p> <p>Background</p> <p>The goals of the study were to assess the relationship between age and processes of care in emergency department (ED) patients admitted with pneumonia and to identify independent predictors of failure to meet recommended quality care measures.</p> <p>Methods</p> <p>This was a prospective cohort study of a pre-existing database undertaken at a university hospital ED in the Midwest. ED patients ≥18 years of age requiring admission for pneumonia, with no documented use of antibiotics in the 24 hours prior to ED presentation were included. Compliance with Pneumonia National Quality Measures was assessed including ED antibiotic administration, antibiotics within 4 hours, oxygenation assessment, and obtaining of blood cultures. Odds ratios were calculated for elders and non-elders. Logistic regression was used to identify independent predictors of process failure.</p> <p>Results</p> <p>One thousand, three hundred seventy patients met inclusion criteria, of which 560 were aged ≥65 years. In multiple variable logistic regression analysis, age ≥65 years was independently associated with receiving antibiotics in the ED (odds ratio [OR] = 2.03, 95% CI 1.28–3.21) and assessment of oxygenation (OR = 2.10, 95% CI, 1.18–3.32). Age had no significant impact on odds of receiving antibiotics within four hours of presentation (OR 1.10, 95% CI 0.84–1.43) or having blood cultures drawn (OR 1.02, 95%CI 0.78–1.32). Certain other patient characteristics were also independently associated with process failure.</p> <p>Conclusion</p> <p>Elderly patients admitted from the ED with pneumonia are more likely to receive antibiotics while in the ED and to have oxygenation assessed in the ED than younger patients. The independent association of certain patient characteristics with process failure provides an opportunity to further increase compliance with recommended quality measures in admitted patients diagnosed with pneumonia.</p

Off the Couch and Onto the Streets: Toward an Ethnographic Psychoanalysis

Psychoanalysis has much to gain by incorporating ethnographic methods into its repertoire. Recent works in ethnographic psychoanalysis demonstrate how psychoanalysis stands to function better as both community intervention and participatory action research. This article describes the historical convergence between psychoanalysis and cultural anthropology and situates ethnographic psychoanalysis within interdisciplinary theory and practice

Cardiac Complications in Patients with Community-Acquired Pneumonia: A Systematic Review and Meta-Analysis of Observational Studies

Vicente Corrales-Medina and colleagues report estimates of the risk of cardiac complications among patients with community-acquired pneumonia from a systematic review and meta-analysis