STUDIES ON VIRULENCE : II. THE INCREASE IN VIRULENCE IN VITRO OF A STRAIN OF PNEUMOCOCCUS.

1. An automatic apparatus is described by which a new supply of food can be furnished actively growing organisms at any desired interval of time—an automatic transferring device. 2. A single strain of pneumococcus, Type I, Neufeld, which had become avirulent for mice, acquired virulence of maximal degree when grown in the described apparatus with skimmed milk sterilized in an Arnold sterilizer as the medium. Transfers were made at intervals of 2, 4, and 8 hours. It is difficult to determine the best interval of transfer, but the 8 hour interval apparently is most suitable, with the 4 and 2 hour following in preference in the order named. 3. Pasteurized skimmed milk from a single dairy, but obtained on different days, when used as medium at a 2 hour interval, varied in effect on the virulence of pneumococci, the results showing that the virulence might be either increased, decreased, or maintained. 4. Skimmed milk heated for varying lengths of time, 30 minutes at 17 pounds pressure, or 60 or 90 minutes at the same pressure, lost its suitability for maintaining virulence of a pneumococcus when transferred every 2 hours, the effect being in direct proportion to the length of time the milk was heated. 5. The H ion concentration of milk had slight effect on virulence. A virulent strain of pneumococcus was grown in milk adjusted to pH = 5, 6, 7, 8, and 9, transfers being made every 2 hours. Virulence was maintained to a like degree on milk titrated to pH = 5, 6, and 7, but when the organism was grown in milk of pH = 8 and 9, virulence decreased, more rapidly at pH = 9 than at pH = 8. 6. A pure line practically avirulent strain of pneumococcus picked by the Barber method, when grown in milk at a 4 hour interval of transfer, increased in virulence 10 million fold; that is to say, until one diplococcus would kill a mouse. Prior to this study, no record has been found in which the virulence of any microorganism has been increased to such a degree by an in vitro method.     

Making short-term climate forecasts useful: Linking science and action

This paper discusses the evolution of scientific and social understanding that has led to the development of knowledge systems supporting the application of El Niño-Southern Oscillation (ENSO) forecasts, including the development of successful efforts to connect climate predictions with sectoral applications and actions “on the ground”. The evolution of “boundary-spanning” activities to connect science and decisionmaking is then discussed, setting the stage for a report of outcomes from an international workshop comprised of producers, translators, and users of climate predictions. The workshop, which focused on identifying critical boundary-spanning features of successful boundary organizations, included participants from Australia, Hawaii, and the Pacific Islands, the US Pacific Northwest, and the state of Ceará in northwestern Brazil. Workshop participants agreed that boundary organizations have multiple roles including those of information broker, convenor of forums for engagement, translator of scientific information, arbiter of access to knowledge, and exemplar of adaptive behavior. Through these roles, boundary organizations will ensure the stability of the knowledge system in a changing political, economic, and climatic context. The international examples reviewed in this workshop demonstrated an interesting case of convergent evolution, where organizations that were very different in origin evolved toward similar structures and individuals engaged in them had similar experiences to share. These examples provide evidence that boundary organizations and boundary-spanners fill some social/institutional roles that are independent of culture.     

Stress,Inflammation and Pain: A Potential Role for Monocytes in Fibromyalgia‐related Symptom Severity

The possibility that immunological changes might contribute to symptom severity in fibromyalgia (FM) prompted this proof‐of‐concept study to determine whether differences in monocyte subpopulations might be present in persons with FM compared with healthy controls. Relationships were assessed by comparing specific symptoms in those with FM (n = 20) and patterns of monocyte subpopulations with healthy age‐matched and gender‐matched controls (n = 20). Within the same time frame, all participants provided a blood sample and completed measures related to pain, fatigue, sleep disturbances, perceived stress, positive and negative affect and depressed mood (and the Fibromyalgia Impact Questionnaire for those with FM). Monocyte subpopulations were assessed using flow cytometry. No differences were observed in total percentages of circulating monocytes between the groups; however, pain was inversely correlated with percentages of circulating classical (r = ?0.568, p = 0.011) and intermediate (r = ?0.511, p = 0.025) monocytes in the FM group. Stress and pain were highly correlated (r = 0.608, p = 0.004) in the FM group. The emerging pattern of changes in the percentages of circulating monocyte subpopulations concomitant with higher ratings of perceived pain and the correlation between stress and pain found in the FM group warrant further investigation. Copyright © 2015 John Wiley & Sons, Ltd.     

High risk of loss to follow‐up among South African children on ART during transfer,a retrospective cohort analysis with community tracing

Introduction : Decentralization of HIV care for children has been recommended to improve paediatric outcomes by making antiretroviral treatment (ART) more accessible. We documented outcomes of children transferred after initiating ART at a large tertiary hospital in the Eastern Cape of South Africa. Methods : Electronic medical records for all children 0–15 years initiating ART at Dora Nginza Hospital (DNH) in Port Elizabeth, South Africa January 2004 to September 2015 were examined. Records for children transferred to primary and community clinics were searched at 16 health facilities to identify children with successful (at least one recorded visit) and unsuccessful transfer (no visits). We identified all children lost to follow‐up (LTF) after ART initiation: those LTF at DNH (no visit >6 months), children with unsuccessful transfer, and children LTF after successful transfer (no visit >6 months). Community tracing was conducted to locate caregivers of children LTF and electronic laboratory data were searched to measure reengagement in care, including silent transfers. Results : 1,582 children initiated ART at median age of 4 years [interquartile range (IQR): 1–8] and median CD4+ of 278 cells/mm³ [IQR: 119–526]. A total of 901 (57.0%) children were transferred, 644 (71.5%) to study facilities; 433 (67.2%) children had successful transfer and 211 (32.8%) had unsuccessful transfer. In total, 399 children were LTF: 105 (26.3%) from DNH, 211 (52.9%) through unsuccessful transfer and 83 (20.8%) following successful transfer. Community tracing was conducted for 120 (30.1%) of 399 children LTF and 66 (55.0%) caregivers were located and interviewed. Four children had died. Among 62 children still alive, 8 (12.9%) were reported to not be in care or taking ART and 18 (29.0%) were also not taking ART. Overall, 65 (16.3%) of 399 children LTF had a laboratory result within 18 months of their last visit indicating silent transfer and 112 (28.1%) had lab results from 2015 to 2016 indicating current care. Conclusion : We found that only two‐thirds of children on ART transferred to primary and community health clinics had successful transfer. These findings suggest that transfer is a particularly vulnerable step in the paediatric HIV care cascade.