Candidate Electromagnetic Counterpart to the Binary Black Hole Merger Gravitational-Wave Event S190521g.

We report the first plausible optical electromagnetic counterpart to a (candidate) binary black hole merger. Detected by the Zwicky Transient Facility, the electromagnetic flare is consistent with expectations for a kicked binary black hole merger in the accretion disk of an active galactic nucleus [B. McKernan, K. E. S. Ford, I. Bartos et al., Astrophys. J. Lett. 884, L50 (2019)AJLEEY2041-821310.3847/2041-8213/ab4886] and is unlikely [

Operative strategy for fistula-in-ano without division of the anal sphincter.

INTRODUCTION: The treatment of perianal fistulas is diverse because no single technique is universally effective. Fistulotomy remains the most effective way of eradicating the pathology but it renders the patient at some risk of faecal incontinence, which many patients are reluctant to take. There are no data in the literature to indicate the healing rate of perianal fistulas when using an operative strategy that routinely avoids division of any part of the anal sphincter. The aim of this paper is to present the long-term results with an operative strategy that aims to avoid division of any part of the anal sphincter complex when treating all types of perianal fistulas, thereby minimising/eliminating the risk of postoperative incontinence. METHODS: We report 54 consecutive cases of anal fistula that presented electively and as an emergency. Patients with known or subsequently diagnosed inflammatory bowel disease or malignancy were excluded from the study. RESULT: Overall, 46 patients (37 male and 9 female) with a median age at presentation of 42 years (range: 19-73 years) were treated by lay-open of the subcutaneous tract of the perianal fistula and insertion of a loose seton for the part of the fistula tract related to the sphincter complex. The types of fistula treated were intersphincteric (89%), transsphincteric (4%) and high suprasphincteric (7%). The median length of time that the seton was left in place was 7 months (range: 1.5-24 months). The healing rate was 86% with a recurrence rate of 19% and a median follow-up duration of 42 months. CONCLUSIONS: Patients who are reluctant to take any risk of faecal incontinence could be treated using an operative strategy that routinely avoids division of any part of the anal sphincter complex as this has a recurrence rate that compares well with other treatment modalities.

Uptake of abdominal aortic aneurysm screening. A cohort study.

BACKGROUND: Abdominal aortic aneurysms (AAA) are responsible for 1.4% of UK deaths. Deprivation is a risk factor for AAA. Screening reduces AAA related mortality and is cost effective if uptake remains high. The Highland aneurysm screening programme (HASP) began in 2001 offering screening to men in a sparsely populated area. The aim was to identify whether uptake varies with deprivation or rurality, in the context of an established programme. METHODS: Retrospective interrogation of HASP records was performed on all men offered screening from 2001 until 2010. Deprivation and rurality status were derived from postcode of residence (SIMD'09 and URC'08) and the relationships with screening uptake were examined. RESULTS: Mean uptake over the decade was 90.1%. There was a strong association between deprivation and uptake, which ranged from 79.5% in the most deprived population to 97.5% in the least deprived (p < 0.001). The odds of men who were least deprived attending was 10.6 times higher than those who were most deprived (p < 0.001). Higher uptake was observed in more rural areas (p = 0.02). When combined in a logistic regression model, only deprivation remained significant, indicating any apparent effect of rurality was explained by deprivation. No change was observed in the mean aortic diameter of 65-year-old men or the incidence of AAA. CONCLUSION: HASP has a high uptake even in the most deprived and rural populations, demonstrating that programme design has overcome any potential rural disadvantage. A gradient of uptake associated with deprivation remains, although even the most deprived have an uptake of almost 80%.

Altruistic self-removal of health-compromised honey bee workers from their hive.

Social insect colonies represent distinct units of selection. Most individuals evolve by kin selection and forgo individual reproduction. Instead, they display altruistic food sharing, nest maintenance and self-sacrificial colony defence. Recently, altruistic self-removal of diseased worker ants from their colony was described as another important kin-selected behaviour. Here, we report corroborating experimental evidence from honey bee foragers and theoretical analyses. We challenged honey bee foragers with prolonged CO(2) narcosis or by feeding with the cytostatic drug hydroxyurea. Both treatments resulted in increased mortality but also caused the surviving foragers to abandon their social function and remove themselves from their colony, resulting in altruistic suicide. A simple model suggests that altruistic self-removal by sick social insect workers to prevent disease transmission is expected under most biologically plausible conditions. The combined theoretical and empirical support for altruistic self-removal suggests that it may be another important kin-selected behaviour and a potentially widespread mechanism of social immunity.

Prevalence of adult-onset multifactorial disease among offspring of atomic bomb survivors.

The first study to examine whether parental radiation exposure leads to increased heritable risk of common adult-onset multifactorial diseases (i.e., hypertension, diabetes mellitus, hypercholesterolemia, ischemic heart disease, and stroke) was conducted among 11,951 participants in the clinical examination program out of a potential of 24,673 mail survey subjects who were offspring of survivors born from May 1946 through December 1984. Logistic regression analyses demonstrated no evidence of an association between the prevalence of multifactorial diseases in the offspring and parental radiation exposure, after adjusting for age, city, gender and various risk factors. The odds ratio (OR) for a paternal dose of 1 Gy was 0.91 [95% confidence interval (CI) 0.81-1.01, P = 0.08], and that for a maternal dose of 1 Gy was 0.98 (95% CI 0.86-1.10, P = 0.71). There was no apparent effect of parental age at exposure or of elapsed time between parental exposure and birth, but male offspring had a low odds ratio (OR = 0.76 at 1 Gy) for paternal exposure, but cautious interpretation is needed for this finding. The clinical assessment of nearly 12,000 offspring of A-bomb survivors who have reached a median age of about 50 years provided no evidence for an increased prevalence of adult-onset multifactorial diseases in relation to parental radiation exposure.

Cell death and thymic export during fetal life.

In the fetus the peripheral T cell pool expands as the fetus grows, but the mechanisms that regulate T cell homeostasis during fetal life are unknown. Here, we show that the peripheral T cell pool in the sheep fetus is established by the export from the fetal thymus of twice as many CD8+ as CD4+ thymic emigrants every day. Clonal deletion of CD4+ thymocytes in the fetal thymus appeared to be more stringent than was the case for CD8+ thymocytes because only 1 in 35 single-positive CD4 (SPCD4) thymocytes was exported from the thymus whereas the majority (2/3) of the single-positive CD8 (SPCD8) thymocytes were exported from the fetal thymus each day. Furthermore, within the thymus, the number of apoptotic SPCD4 thymocytes was 40 times greater than the number of apoptotic SPCD8 thymocytes. A tissue-specific migration of CD8+ emigrants localizing in the spleen was also established in the fetus in contrast to CD4+ emigrants, which migrated randomly to spleen and LN.

Tracking dendritic cells: use of an in situ method to label all blood leukocytes.

Here we describe an in situ procedure with a labeling index (percent of labeled blood leukocytes) >98%, which is high enough to permit the direct tracking of dendritic cell (DC) precursors from blood into lymphoid tissues, while circumventing the pitfalls associated with in vitro labeling. DC and lymphocytes have similar blood to afferent lymph migratory capabilities. This method has additional applications in tracking other rare cell populations in both normal and pathological states.