Helical computed tomographic angiography for the diagnosis of traumatic arterial injuries of the extremities

BACKGROUND: The radiologic study of choice for evaluation of traumatic arterial injuries is conventional arteriography, but it poses the risks of an invasive procedure. Computed tomographic arteriography (CTA) is emerging as a new way to study arterial anatomy, with the additional advantages of being noninvasive and a technique that allows evaluation of different body areas simultaneously. Our experience using CTA for evaluation of traumatic arterial injuries is provided in this study. METHODS: A retrospective review over a 22-month period of all adult patients undergoing CTA for evaluation of traumatic injuries to the extremities was performed. RESULTS: A total of 97 CTA studies were performed in the 95 patients. CTA adequately demonstrated the nature and location of all the arterial injuries when compared with conventional arteriography or surgical exploration. Abnormal CTA results included 21 arterial occlusions, 2 intimal flap defects, and 2 pseudoaneurysms. Nine of these 25 injuries were confirmed by surgery only, 10 by surgery and arteriography, and 6 by arteriography only. Normal CTA results were confirmed with arteriography in 10 cases. No missed injuries were encountered in patients with normal CTA results. CONCLUSION: CTA is a reliable technique for the detection and characterization of traumatic extremity arterial injuries. These results suggest CTA may be an alternative to conventional arteriography for the diagnosis of traumatic arterial injuries.     

The HORIZON Recurrent Fracture Trial: design of a clinical trial in the prevention of subsequent fractures after low trauma hip fracture repair

OBJECTIVE: To present the novel design of a trial testing the safety and efficacy of a yearly bisphosponate, zoledronic acid, in preventing new clinical fractures in patients with recent low trauma hip fracture repair. Research design and methods: Randomized, placebo-controlled, triple-blind study. One hundred and fifteen clinical centers worldwide are recruiting approximately 1714 subjects aged 50 years and over (no upper age limit, median age of enrolled subjects to date 79 years) who have undergone surgical repair of a low trauma hip fracture in the preceding 90 days. Patients will be assigned at random to an intervention group (5 mg zoledronic acid intravenously yearly) or a control group (placebo infusion yearly). Both groups receive a loading dose of Vitamin D2 or D3 IM or orally, followed by 800-1200 IU Vitamin D and 1000-1500 mg elemental calcium orally on a daily basis. Concomitant therapy with calcitonin, hormone replacement therapy, selective estrogen receptor modulators, tibolone, and external hip protectors are allowed. MAIN OUTCOME MEASURES: The primary endpoint is subsequent skeletal fractures as adjudicated by a clinical endpoints committee blinded to intervention status. Secondary outcomes include delayed hip fracture healing, changes in bone mineral density, and health resource utilization. Subjects will be recruited over a 3-4 year period and will be followed until 211 primary endpoints are accrued and adjudicated. CONCLUSIONS: This randomized clinical trial is novel among osteoporosis therapies as it (1). targets hip fracture patients, a previously understudied group, and (2). uses only clinically evident fractures as the primary outcome. Ethical and practical considerations in studying this frail population are discussed.     

Comparative fibrinolytic activity of front-loaded alteplase and the single-bolus mutants tenecteplase and lanoteplase during treatment of acute myocardial infarction

Background Quantification of fibrinolytic activity (FAct) in clinical practice has been abandoned because of the complexity of existing assays. The relationship between thrombolytic drug concentration and FAct is complex. FAct profiles of currently used thrombolytic drugs were not characterized. Methods By use of a system that quantifies FAct by shortening of clot lysis onset time (LOT), we measured LOT in vitro with incremented concentrations of alteplase (t-PA) and tenecteplase (TNK-tPA) and ex vivo in patients with acute myocardial infarction who were receiving front-loaded t-PA (n = 31), 30 to 40 mg TNK-tPA (n = 19), and 120 kU/kg lanoteplase ([n-PA] n = 23). Results In vitro, FAct depended on drug concentration by means of a double exponential model revealing 2 distinct activity zones (weak/strong). Ex vivo, no FAct was detected before agent administration (LOT > 1200 seconds). Ten minutes after a bolus was given, FAct was sharply increased in all patients, but it increased more with TNK-tPA than with t-PA or n-PA (mean LOT of 109, 125, and 130 seconds, respectively, P < .05). At 90 minutes, accelerated infusion of t-PA resulted in FAct that remained stronger than that observed for TNK-tPA (P < .0001) or n-PA (P = .011). At 180-minutes, significant FAct (LOT <600 seconds) was only observed in patients who received n-PA. Conclusion This study provides the first direct comparison of FAct between t-PA, TNK-tPA, and n-PA by use of the LOT test, the results of which are reliably related to drug concentration. The ideal FAct profile would combine an immediate strong FAct of relatively short duration, as seen with TNK-tPA, that may contribute to its better efficacy/safety profile in the Assessment of Safety and Efficacy of a New Thrombolytic Agent-2 (ASSENT-2) trial. Prolonged FAct after n-PA may contribute to increased hemorrhagic complications, as seen in the Intravenous n-PA for Treatment of Infarcting Myocardium Early-2 (InTIME-2) trial. Thus, characterizing FAct profiles might provide insights in developing more efficient thrombolytic regimens. (Am Heart J 2003;145:217-25)     

Characterization of somatostatin binding sites in cytosolic fraction of pig retina

Specific binding sites for somatostatin have been characterized in the cytosolic fraction of the pig retina. The interaction of 125I-Tyr11-somatostatin with cytosolic fraction was rapid, reversible, specific, saturable and temperature-dependent. At 15 degrees C, the binding data were compatible with the existence of two classes of binding sites: a high-affinity class with a Kd of 16.1 nM and a low-affinity class with a Kd of 236.4 nM. The presence of somatostatin binding sites in the cytosolic fraction of the retina, together with the known occurrence of somatostatin at this level, strongly suggest that this peptide may be involved in the physiology of the retina.     

Residential status and HIV risk behaviors among Puerto Rican drug injectors in New York and Puerto Rico.

This article investigates the association between residential status and human immunodeficiency virus (HIV) risk behaviors among island and New York Puerto Rican injection drug users (IDUs). We assigned 561 subjects from New York City and 312 from Puerto Rico to five residential status categories: living in parent's home, living in own home, living in other's home, living in temporary housing (hotel, single-room occupancy [SRO] hotels), and homeless (living in streets/shelters). Dependent variables included injection- and sex-related risk behaviors (sharing syringes, sharing other injection paraphernalia, shooting gallery use, and having paid sex). Chi square, t tests, and multivariate logistic analysis tests were performed separately by site. About one-quarter of the sample in each site was homeless. Island Puerto Ricans were more likely to live with their parents (44% vs. 12%, p < .001), and more New York IDUs lived in their own home (30% vs. 14%, p < .001). In New York, gallery use and paid sex were associated with living in other's home, living in parent's home, and being homeless. Sharing paraphernalia was related to living in other's home, living in temporary housing, and being homeless. In Puerto Rico, having paid sex was associated with homelessness. High-risk behaviors were more likely among homeless IDUs in both sites. Programs to provide housing and target outreach and other prevention programs for homeless IDUs would be helpful in reducing HIV risk.     

Transnational Mortality Comparisons Between Archipelago and Mainland Puerto Ricans

Puerto Ricans in the US experience higher deaths from diabetes and other causes compared to non-Hispanic Whites and other Hispanic groups. We compared mortality in Puerto Rico to that of Puerto Ricans in the US as a first step to investigate if similar or worse mortality patterns originate from the sending country (Puerto Rico). Age-adjusted death rates were generated using national vital statistics databases in the US and territories for all-cause and the top ten causes of death among Hispanics in 2009. Mortality ratios in the archipelago of Puerto Rico (APR) were compared to mainland US Puerto Ricans (MPR). Rates for other ethnic/racial groups (Mexican Americans, Cubans, and non-Hispanic Whites, Blacks, American Indians, and Asians) were calculated to provide a context. APR had significantly higher all-cause mortality and death rates for diabetes, nephritis, pneumonia/influenza, and homicide/assault compared to MPR (APR/MPR ratio for all-cause: 1.08, diabetes: 2.04, nephritis: 1.84, pneumonia/influenza: 1.33, homicide/assault: 3.15). Death rates for diabetes and homicide/assault (particularly among men) were higher among APR compared to any other racial/ethnic groups in the US. In contrast, deaths from heart disease, cancer, and chronic liver disease were significantly lower for APR compared to MPR (MPR/APR ratio 0.72, 0.91, 0.41, respectively). Among APR women, death rates for these causes were also lower compared to any other group in the US. Substantial mortality variability exists between Puerto Ricans in Puerto Rico and those in the US, re-emphasizing the need to study of how socio-environmental determinants of health differ in sending and receiving countries. Explanations for disparate rates include access to and availability of healthcare and unique factors related to the migration experience of this group.     

Barriers to and Suggestions for a Healthful,Active Lifestyle as Perceived by Rural and Urban Costa Rican Adolescents

ObjectiveTo assess the perceptions of rural and urban Costa Rican adolescents regarding which barriers and motivators affect their adoption of an active lifestyle.DesignData were collected in focus group discussions.Participants108 male and female adolescents aged 12 to 18 from the 7th to 11th grades.SettingTwo urban and 1 rural high school in San José, Costa Rica.Phenomena of InterestActive lifestyle; barriers and motivators for active life.AnalysisData were reviewed for emerging themes, and themes were coded using content analysis procedures.ResultsMajor barriers: (a) physical education curriculum was focused on competitive sports; (b) lack of facilities in the school and community environments; (c) family did not provide good role models and reinforced the socially expected gender roles. Key motivators: (a) changed the physical education curriculum to focus on leisure and recreational activities; (b) increased the availability of facilities both in the school and in the community; and (c) provided a strong social support network.Conclusions and ImplicationsThe school, community, and family environments are potential targets for physical activity interventions for adolescents. Future studies should explore in depth the influence of adolescent socialization patterns (particularly for females) in the establishment of an active lifestyle.     

An institutional ethnography of prevention and treatment services for substance use disorders in the Dominican Republic

ABSTRACT

The Dominican Republic is thought to have significant epidemics of illicit drug use but lacks surveillance and formal analyses of the policy context of drug prevention and treatment services. We conducted an institutional ethnography of 15 drug service organisations in Santo Domingo and Boca Chica, Dominican Republic, to explore barriers and resources for drug abuse prevention and treatment. Here, we present a typology of drug service organisations based on their services, methods, and approach. We then draw on interviews with representatives of drug service institutions to describe the primary barriers to drug treatment and prevention services for drug users. We conclude with a focus on the policy priorities that could improve the conditions of health care for marginalised drug users in the Dominican Republic.