Sanatoria revisited: sunlight and health

Since the 18th century tuberculosis has been a major cause of death throughout the world. It is a highly infectious disease that spreads by droplet infection and finding effective treatment to combat tuberculosis took a great deal of time. One of the first treatments to have some real success was a stay in a sanatorium. Sanatoria were homes that provided patients with good food and fresh air (and therefore sunlight). The first sanatorium to use sunlight therapy (heliotherapy) seriously was founded in Leysin, Switzerland, by Auguste Rollier. Patients built up their sun exposure gradually to prevent sunburn or skin damage. We suggest that heliotherapy was more successful in treating tuberculosis than was appreciated once chemotherapy became available. The birth of heliotherapy coincided with an increased appreciation of the association of sunlight and health among the general public. The secret of its success is the combined effects of sunlight on the skin inducing the production of nitric oxide and vitamin D. Nitric oxide is not only a messenger in the cardiovascular system and responsible for relaxation of vascular muscle but is also involved in the innate immune system. Vitamin D is responsible for immune system functions and multiple studies have found an association between tuberculosis immunity and high vitamin D levels. Therefore, it is understandable that providing tuberculosis patients with sunlight may have boosted their immune system and aided them in the fight against tuberculosis. In view of the high level of resistance to all drug regimens in some patients, perhaps it is time to revive the use of sanatoria in the fight against tuberculosis

Could misreporting of condom use explain the observed association between injectable hormonal contraceptives and HIV acquisition risk?

OBJECTIVE: Some observational studies have suggested an association between the use of hormonal contraceptives (HC) and HIV acquisition. One major concern is that differential misreporting of sexual behavior between HC users and nonusers may generate artificially inflated risk estimates. STUDY DESIGN: We developed an individual-based model that simulates the South African HIV serodiscordant couples analyzed for HC-HIV risk by Heffron et al. (2012). We varied the pattern of misreporting condom use between HC users and nonusers and reproduced the trial data under the assumption that HC use is not associated with HIV risk. The simulated data were analyzed using Cox proportional hazards models, adjusting for the reported level of condom use. RESULTS: If HC users overreport condom use more than nonusers, an apparent excess risk could be observed even without any biological effect of HC on HIV acquisition. With 45% overreporting by HC users (i.e., 9 out of every 20 sex acts reported with condoms are actually unprotected) and accurate condom reporting by nonusers, a true null effect can be inflated to give an observed hazard ratio (HR̂) of 2.0. In a different population with lower overall reported condom use, artificially high HR̂s can only be generated if non-HC users underreport condom use. CONCLUSION: Differential condom misreporting can theoretically produce inflated HR̂ values for an association between HC and HIV even without a true association. However, to produce a doubling of HIV risk that is entirely spurious requires substantially different levels of misreporting among HC users and nonusers, which may be unrealistic. IMPLICATIONS: Considerably differential amounts of condom use misreporting by HC users and nonusers would be needed to produce entirely spurious observed levels of excess HIV acquisition risk among HC users when there is actually no true association

Fine-scale hydrodynamics influence the spatio-temporal distribution of harbour porpoises at a coastal hotspot

The coastal Runnelstone Reef, off southwest Cornwall (UK), is characterised by complex topography and strong tidal flows and is a known high-density site for harbour porpoise (. Phocoena phocoena); a European protected species. Using a multidisciplinary dataset including: porpoise sightings from a multi-year land-based survey, Acoustic Doppler Current Profiling (ADCP), vertical profiling of water properties and high-resolution bathymetry; we investigate how interactions between tidal flow and topography drive the fine-scale porpoise spatio-temporal distribution at the site. Porpoise sightings were distributed non-uniformly within the survey area with highest sighting density recorded in areas with steep slopes and moderate depths. Greater numbers of sightings were recorded during strong westward (ebbing) tidal flows compared to strong eastward (flooding) flows and slack water periods. ADCP and Conductivity Temperature Depth (CTD) data identified fine-scale hydrodynamic features, associated with cross-reef tidal flows in the sections of the survey area with the highest recorded densities of porpoises. We observed layered, vertically sheared flows that were susceptible to the generation of turbulence by shear instability. Additionally, the intense, oscillatory near surface currents led to hydraulically controlled flow that transitioned from subcritical to supercritical conditions; indicating that highly turbulent and energetic hydraulic jumps were generated along the eastern and western slopes of the reef. The depression and release of isopycnals in the lee of the reef during cross-reef flows revealed that the flow released lee waves during upslope currents at specific phases of the tidal cycle when the highest sighting rates were recorded. The results of this unique, fine-scale field study provide new insights into specific hydrodynamic features, produced through tidal forcing, that may be important for creating predictable foraging opportunities for porpoises at a local scale. Information on the functional mechanisms linking porpoise distribution to static and dynamic physical habitat variables is extremely valuable to the monitoring and management of the species within the context of European conservation policies and marine renewable energy infrastructure development

Posterior cricoid region fluoroscopic findings: the posterior cricoid plication.

The region posterior to the cricoid cartilage is challenging to assess fluoroscopically. The purpose of this investigation is to critically evaluate the posterior cricoid (PC) region on fluoroscopy and describe patterns of common findings. This was a case control study. All fluoroscopic swallowing studies performed between June 16, 2009, and February 9, 2010, were reviewed for features seen in the PC region. These findings were categorized into distinct patterns and compared to fluoroscopic studies performed in a cohort of normal volunteers. Two hundred patient studies and 149 healthy volunteer studies were reviewed. The mean age of the referred patient cohort and the volunteer cohort was 57 years (±19) and 61 years (±16), respectively (p > 0.05). The patient cohort was 53% male and the control cohort was 56% female (p > 0.05). Four groups were identified. Pharyngoesophageal webs were seen in 7% (10/149) of controls and 14% (28/200) of patients (p = 0.03). A PC arch impression was seen in 16% of patients (32/200) and controls (24/149) (p = 1). A PC plication was demonstrated in 23% (34/149) of controls and 30% (60/200) of patients (p = 0.13). No distinctive PC region findings were seen in 54% (81/149) of controls and 42% (84/200) of referred patients (p = 0.02). Four patients (2%) had both a web and a PC plication. Four categories of PC region findings were identified (unremarkable PC region, web, PC arch impression, and PC plication). Both patients referred for swallowing studies and healthy volunteers demonstrated esophageal webs, PC arch impressions, and PC plications. Only webs were more common in patients than in control subjects (p = 0.03). The PC impression and PC plication are likely to represent normal variants that may be identified on fluoroscopic swallow studies

Biomarkers of potential harm in people switching from smoking tobacco to exclusive e-cigarette use, dual use or abstinence: secondary analysis of Cochrane systematic review of trials of e-cigarettes for smoking cessation

Aims This study aims to compare biomarkers of potential harm between people switching from smoking combustible cigarettes (CC) completely to electronic cigarettes (EC), continuing to smoke CC, using both EC and CC (dual users) and using neither (abstainers), based on behaviour during EC intervention studies. Design Secondary analysis following systematic review, incorporating inverse variance random-effects meta-analysis and effect direction plots. Setting This study was conducted in Greece, Italy, Poland, the United Kingdom and the United States. Participants A total of 1299 adults smoking CC (nine studies) and provided EC. Measurements Measurements were conducted using carbon monoxide (CO) and 26 other biomarkers. Findings In pooled analyses, exhaled CO (eCO) was lower in EC versus EC + CC [mean difference (MD) = −4.40 parts per million (p.p.m.), 95% confidence interval (CI) = −12.04 to 3.24, two studies] and CC (MD = −9.57 p.p.m., 95% CI = −17.30 to −1.83, three studies). eCO was lower in dual users versus CC only (MD = −1.91 p.p.m., 95% CI = −3.38 to −0.45, two studies). Magnitude rather than direction of effect drove substantial statistical heterogeneity. Effect direction plots were used for other biomarkers. Comparing EC with CC, 12 of 13 biomarkers were significantly lower in EC users, with no difference for the 13th. Comparing EC with dual users, 12 of the 25 biomarkers were lower for EC, and five were lower for dual use. For the remaining eight measures, single studies did not detect statistically significant differences, or the multiple studies contributing to the outcome had inconsistent results. Only one study provided data comparing dual use with CC; of the 13 biomarkers measured, 12 were significantly lower in the dual use group, with no statistically significant difference detected for the 13th. Only one study provided data on abstainers. Conclusions Switching from smoking to vaping or dual use appears to reduce levels of biomarkers of potential harm significantly