Organizational networks in road safety: Case studies of U.S. Vision Zero cities.

Objective: Each year, more than 30,000 deaths occur on U.S. roads. Recognizing the magnitude and persistence of this public health problem, a number of U.S. cities have adopted a relatively new approach to prevention, termed Vision Zero (VZ). VZ has been adopted by more than 30 U.S. cities and calls for creating a transportation system that ensures that no road traffic crash results in death or serious injury. A core component of VZ is strong multidisciplinary and multisector stakeholder engagement, and cities adopting VZ often establish a VZ coalition to foster stakeholder collaboration. However, there is little information on the structure, development, and functioning of coalitions working to achieve VZ and on tools available to study and evaluate such coalition functioning. We sought to describe the characteristics of prominent U.S. VZ city coalitions and context surrounding VZ uptake and advancement in these cities. Moreover, we demonstrate use of network analysis as one tool for exploring the structure of interorganizational relationships in coalitions. Methods: We conducted case studies of 4 prominent U.S. VZ city coalitions in 2017-2018. We summarized coalition members' characteristics and responses to questions about their cities' VZ adoption, planning, and implementation. We asked each coalition member to provide information on their contact frequency, perceived productivity, and resource sharing with every other coalition member in their city and used network analysis techniques in 2 cities to understand the structures and relationships in coalitions. Results: Findings indicated that government agencies generally constituted the majority of coalition members and often played central roles in terms of coalition network contact, productivity, and resource flow. Other emerging similarities regarding coalition establishment and VZ implementation included the need for political support, the importance of formal plan development, and increased collaboration and cooperation among partners. Conclusions: Organizational network analyses, enriched with coalition member interviews, can elucidate key aspects of coalition creation, attributes, and relationship structure. The case studies of leading VZ coalition networks presented here highlight the use of these tools. Ultimately, understanding associations between VZ network structures and attributes and road safety outcomes could help inform effective coalition adoption, implementation, and maintenance to optimize safety outcomes.

IGA antiphospholipid antibodies in HLTV-1-associated tropical spastic paraparesis

A retrovirus human T cell lymphotropic virus type I (HTLV-I), is an essential but not a sufficient aetiological factor for tropical spastic paraparesis (TSP). Because some TSP patients have biological false positive tests for trepomemal infections (BFP-STS), we used EISA to study BFP-STS and anticardiolipin antibodies in 42 Jamaican TSP patients. The data indicate that in TSP anticardiolipin antibodies accur in about 26 percent of patients, are associated with biological false positive treponemal serology, are relatively restricted to the IgA isotype and may be induced by HTLV-I or other non-treponemal infections. (Au)

Clinical and genetic aspects of primary antiphospholipid antibody syndrome - abstract

Antibodies against phopholipids are associated with recurrent arterial and venous thromboses, thrombocytopenia and pregnancy loss. This antiphospholipid antibody syndrome is most commonly seen in systemic lupuis erythematosus (SLE); in previous studies we demonstrated that deficiency alleles of the fourth component of the complement system are associated with the presence of antiphospholipid antibodies in SLE. A primary antiphospholipid antibody syndrome is also known to occur in the absence of evidence of a defined connective tissue disorder; the aetiological relationship of this primary antiphospholipid antibody syndrome to SLE is unclear, but previous studies have suggested a genetic basis for some components of this syndrome. We investigated a 26-year-old woman who presented in 1986 with all the features of primary anti-phospholipid antibody syndrome. During the previous 4 years she had developed one episode of deep venous thrombosis and two pregnancy losses during the second trimester. On presentation, she was thrombocytopenic, had a false positive test for syphilis, a circulating lupus anticoagulant and persistently very high levels of IgG anticardiolipin antibody. However, antinuclear antibodies were repeatedly absent from serum. She subsequently developed two episodes of stroke, with radiological evidence of cerebral infarction. The anticardiolipin antibody levels were incompletely suppressed by plasmaphaeresis and intravenous cyclophosphamide, but she improved clinically after anticoagulation with warfarin was instituted. Studies of plasma and of DNA from this patient revealed the presence of a large heterozygous gene deletion at one of loci of the fourth component of the complement system (C4A) and the adjacent 21 hydroxylase-A gene. This deletion was present in only 7 percent of a control normal population. We and others have shown this deletion to be a risk factor for systemic lpus erythematosus. We are continuing long-term follow-up of this patient and studies among her family members to further elucidate the relationship of this and other genetic factors to the antiphospholipid antibody syndrome. This is the first report of the presence of a C4A gene deletion in a patient with the primary antiphospholipid antibody syndrome and it supports the idea that there is a close genetic relationship between this syndrome and systemic lupus erythematosus (AU)