Is It Safe to Prep the External Fixator In Situ During Second-Stage Pilon Surgical Treatment?

OBJECTIVE: To evaluate the infection rate of our protocol of prepping the external fixator in situ during definitive second-stage pilon fracture open reduction internal fixation. DESIGN: Retrospective clinical investigation. SETTING: Academic Level 1 Trauma Center. PATIENTS/PARTICIPANTS: Out of 229 patients with distal tibia fractures presenting to our institution from 1999 to 2014, 100 were treated in a 2-stage fashion utilizing this protocol. INTERVENTION: Prepping the external fixator into the surgical field during the second-stage/definitive open reduction internal fixation procedure. MAIN OUTCOME MEASUREMENT: The rates of deep and superficial infections after definitive fixation. RESULTS: The deep infection rate was 13%, and the superficial infection rate was 11%. CONCLUSIONS: Infection rates using this protocol are comparable to previously reported infection rates for two-stage surgical treatment of pilon fractures. This protocol provides the treating surgeon information about an alternative method to streamline definitive fixation. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Decomposition of nitrosamines in CO2 capture by aqueous piperazine or monoethanolamine.

Amine scrubbing is an efficient method for carbon capture and sequestration, but secondary amines present in all amine solvents can form carcinogenic nitrosamines. Decomposition kinetics for n-nitrosopiperazine (MNPZ), nitrosodiethanolamine (NDELA), and nitroso-(2-hydroxyethyl) glycine (NHeGly) were measured over a range of temperature, base concentration, base strength, and CO2 loading pertinent to amine scrubbing. MNPZ and NDELA decomposition is first order in the nitrosamine, half order in base concentration, and base-catalyzed with a Brønsted slope of ß = 0.5. The activation energy is 94, 106, and 112 kJ/mol for MNPZ, NDELA, and NHeGly, respectively. MNPZ readily decomposes at 150 °C in 5 M piperazine, making thermal decomposition an important mechanism for MNPZ control. However, NHeGly and NDELA are too stable at 120 °C in 7 M monoethanolamine (MEA) for thermal decomposition to be important. Base treatment during reclaiming could rapidly and selectively decompose NHeGly and NDELA to mitigate nitrosamine accumulation in MEA.

The synthesis and the chemical and physical properties of non-aqueous silylamine solvents for carbon dioxide capture.

Silylamine reversible ionic liquids were designed to achieve specific physical properties in order to address effective CO2 capture. The reversible ionic liquid systems reported herein represent a class of switchable solvents where a relatively non-polar silylamine (molecular liquid) is reversibly transformed to a reversible ionic liquid (RevIL) by reaction with CO2 (chemisorption). The RevILs can further capture additional CO2 through physical absorption (physisorption). The effects of changes in structure on (1) the CO2 capture capacity (chemisorption and physisorption), (2) the viscosity of the solvent systems at partial and total conversion to the ionic liquid state, (3) the energy required for reversing the CO2 capture process, and (4) the ability to recycle the solvents systems are reported.

An innovative work-loop calorimeter for in vitro measurement of the mechanics and energetics of working cardiac trabeculae.

We describe a unique work-loop calorimeter with which we can measure, simultaneously, the rate of heat production and force-length work output of isolated cardiac trabeculae. The mechanics of the force-length work-loop contraction mimic those of the pressure-volume work-loops experienced by the heart. Within the measurement chamber of a flow-through microcalorimeter, a trabecula is electrically stimulated to respond, under software control, in one of three modes: fixed-end, isometric, or isotonic. In each mode, software controls the position of a linear motor, with feedback from muscle force, to adjust muscle length in the desired temporal sequence. In the case of a work-loop contraction, the software achieves seamless transitions between phases of length control (isometric contraction, isometric relaxation, and restoration of resting muscle length) and force control (isotonic shortening). The area enclosed by the resulting force-length loop represents the work done by the trabecula. The change of enthalpy expended by the muscle is given by the sum of the work term and the associated amount of evolved heat. With these simultaneous measurements, we provide the first estimation of suprabasal, net mechanical efficiency (ratio of work to change of enthalpy) of mammalian cardiac trabeculae. The maximum efficiency is at the vicinity of 12%.

Meta-analysis of interventions to increase physical activity among cardiac subjects.

BACKGROUND: Extensive primary research has tested interventions to increase physical activity (PA) among adults with cardiovascular disease. This meta-analysis integrates the extant research about how to increase PA in cardiac samples. METHODS: Extensive literature searching located published and unpublished intervention studies that measured PA outcomes. Results were coded from primary studies. Fixed- and random-effects meta-analytic procedures included moderator analyses. RESULTS: Data were synthesized across 11,877 subjects from 79 eligible research reports. The overall mean PA effect size for 2-group comparisons was 0.35 (higher mean for treatment than control), which is consistent with a difference of 1984 kcal/week for treatment subjects versus 1615 for control subjects. The fitness effect size for 2-group comparisons was .17. Other statistically significantly positive 2-group effect sizes were .24 for quality of life and .23 for subsequent cardiac events. Effect sizes for anthropometric measures and blood pressure did not differ significantly from 0. Exploratory moderator analyses found large effect sizes for PA among studies that had (1) an exclusive focus on PA versus diverse health behaviors, (2) more contact between interventionists and subjects, (3) supervised exercise sessions, (4) fitness testing, (5) face-to-face encounters versus mediated intervention delivery, and (6) more minutes of activity per week. Effect sizes were unrelated to funding status, dissemination vehicle, gender distribution, or attrition rate. CONCLUSIONS: These findings document that interventions can be effective in increasing PA among patients with cardiovascular diseases. Primary research should compare interventions in randomized trials to confirm causal relationships.

Meta-analysis of health behavior change interventions in type 1 diabetes.

OBJECTIVES: To meta-analyze research testing interventions to improve health behaviors including exercise among adults with type 1 diabetes. METHODS: Multiple literature-searching strategies identified published and unpublished studies reporting glycated hemoglobin outcomes. Fixed- and random-effects meta-analyses included moderator effects. RESULTS: Data were synthesized across 1435 subjects. The overall effect size was 0.26. This translates into a reduction of 0.33 in mean HbA1c levels between treatment (8.47%) and control (8.80%) groups. Effect sizes were larger with more females, lower body mass index, higher baseline HbA1c, and interventions targeting multiple behaviors. CONCLUSIONS: Behavior change interventions improve metabolic control in type 1 diabetes.

Physical activity interventions among adults with arthritis: meta-analysis of outcomes.

OBJECTIVE: Due to reduced physical activity, adults with arthritis experience significant disability and comorbidities including cardiovascular disease. This meta-analytic review integrates results from primary research studies testing interventions to increase physical activity in arthritis patients. METHODS: Extensive literature searching strategies were employed to locate published and unpublished empirical studies testing physical activity interventions. Results were coded for studies that had at least 5 participants. Effect sizes (ESs) were calculated for measures of physical activity, pain, and objective and subjective measures of functional ability. RESULTS: Twenty-eight research studies with 4111 subjects were synthesized. The mean ES for 2-group comparisons (treatment versus control) was 0.69 for physical activity, 0.21 for pain, 0.49 for objectively measured function, and 0.14 for subjectively measured function. This average effect on subjective function is consistent with a Health Assessment Questionnaire mean of 0.64 for treatment subjects as compared with 0.70 for control subjects. For pain assessed using the 0 to 10 visual analog scale, the average effect amounts to a mean of 3.78 for treatment subjects versus 4.33 for control subjects. Control group subjects experienced statistically significant improvements in pain and, to a lesser extent, objectively measured functional ability during study participation. CONCLUSIONS: Physical activity interventions resulted in moderate positive effects on physical activity behavior and small positive effects on pain and physical function outcomes. Future research should examine specific intervention characteristics that result in optimal results, such as frequency, type, and intensity of exercise.

Meta-analysis of the effect of exercise interventions on fitness outcomes among adults with type 1 and type 2 diabetes.

This review applied meta-analytic procedures to integrate primary research that examined exercise fitness outcomes among adults with type 1 or type 2 diabetes. We used extensive literature searching strategies to locate published and unpublished intervention studies that tested exercise interventions. We conducted meta-analytic procedures using both fixed- and random-effects models. Analyses were conducted separately for type 1 and type 2 diabetes and separately for two-group and single-group data under two assumptions about pre-post fitness outcomes association: no association and a strong positive association (0.80). Codable data were extracted from 35 reports with 1074 subjects. The type 1 diabetes overall weighted mean effect size for two-group comparisons was 0.65. For treatment group pretest versus post-test, the effect was 0.62. The effect size among adults with type 2 diabetes for two-group comparisons was 0.35. The treatment group pretest versus post-test comparison effect was 0.37. Effect sizes among control group participants were not statistically different from 0. For type 2 diabetes two-group comparisons, larger effect sizes were associated with exercise prescription, fitness testing, supervised exercise, group sessions, and recommendations for longer duration exercise sessions. HbA1c, age, body mass index, and gender distribution were unrelated to fitness outcomes.

A meta-analysis of exercise interventions among people treated for cancer.

GOAL: This review applied meta-analytic procedures to integrate primary research findings that tested exercise interventions among people treated for cancer. METHODS: Extensive literature searching strategies located published and unpublished intervention studies that tested exercise interventions with at least five participants (k = 30). Primary study results were coded. Meta-analytic procedures were conducted. MAIN RESULTS: The overall weighted mean effect size (ES) for two-group comparisons was 0.52 (higher mean for treatment than control) for physical function, 0.35 for symptoms other than fatigue, and 0.27 for body composition. More modest positive ESs were documented for mood (0.19), quality of life (0.14), fatigue (0.11), and exercise behavior (0.04). ESs were larger among single-group pre-post design studies. ESs among control group participants were typically negative and not (statistically) significantly different from 0. CONCLUSIONS: Exercise interventions resulted in small positive effects on health and well-being outcomes among existing studies. Future research should examine intervention-specific characteristics that result in optimal results, such as dose.

Detection of bovine torovirus and other enteric pathogens in feces from diarrhea cases in cattle.

The objectives of this study were to determine the prevalence of bovine torovirus (BoTV) in bovine fecal samples from diarrhea cases submitted to the Ohio Animal Disease Diagnostic Laboratory (ADDL) and to assess if a relationship exists between BoTV and the other enteric pathogens detected. From November 1999 to May 2001, 259 specimens from 53 calves (< or = 6 months old), 27 young adults (52 years), 125 adults (> or = 2 years), and 54 animals of unknown age were examined by an antigen-capture enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase-polymerase chain reaction (RT-PCR) assay developed to detect BoTV. Testing for other enteric pathogens was performed by ADDL, and the results were analyzed with the BoTV data. The BoTV was detected using ELISA or RT-PCR in 9.7% (25/259) of the clinical samples, 56% (14/25) of which were from calves (P < 0.001) representing 26.4% (14/53) of the calves tested. Of the BoTV-positive calves, 71% (10/14) were less than 3 weeks of age. In 11/25 positive specimens, BoTV was the only pathogen detected among those examined. Other enteric organisms detected alone or in combination with BoTV in calf samples were rotavirus, coronavirus, Salmonella spp., Cryptosporidium spp., and Giardia spp.; but no consistent association between BoTV and these organisms was observed. In summary, BoTV was detected in fecal samples from cattle with diarrhea, principally in young calves less than 3 weeks of age. Future studies of infectious diarrhea in cattle should also include assays for this etiologic agent.

Association of enteric shedding of bovine torovirus (Breda virus) and other enteropathogens with diarrhea in veal calves.

OBJECTIVE: To determine the prevalence, fecal shedding pattern, and association of bovine torovirus (BoTV) with diarrhea in veal calves at time of arrival and periodically throughout the first 35 days after their arrival on a veal farm. ANIMALS: 62 veal calves. PROCEDURE: Fecal samples collected on days 0, 4, 14, and 35 after arrival were tested for BoTV by use of ELISA and reverse transcriptase-polymerase chain reaction (RT-PCR) assay. Paired serum samples obtained from blood collected on days 0 and 35 were analyzed for BoTV antibodies with a hemagglutination inhibition assay. Fecal samples were also screened for other enteric pathogens, including rotavirus, coronavirus, and Cryptosporidium spp. RESULTS: Fecal shedding of BoTV was detected in 15 of 62 (24%) calves by use of ELISA and RT-PCR assay, with peak shedding on day 4. A significant independent association between BoTV shedding and diarrhea was observed. In addition, calves shedding > or = 2 enteric pathogens were more likely to have diarrhea than calves shedding < or = 1 pathogen. Calves that were seronegative or had low antibody titers against BoTV (< or = 1:10 hemagglutination inhibition units) at arrival seroconverted to BoTV (> 4-fold increase in titer); these calves were more likely to shed virus than calves that were seropositive against BoTV at arrival. CONCLUSIONS AND CLINICAL RELEVANCE: Shedding of BoTV was strongly associated with diarrhea in neonatal veal calves during the first week after arrival at the farm. These data provide evidence that BoTV is an important pathogen of neonatal veal calves.

Detection of respiratory and enteric shedding of bovine coronaviruses in cattle in an Ohio feedlot.

Recently, bovine coronavirus (BCV) has been isolated from new cattle arrivals to feedlots, but the association between respiratory and enteric infections with BCV in feedlot cattle remains uncertain. Fecal and nasal swab samples from 85 Ohio Agricultural Research and Development Center (OARDC) feedlot cattle averaging 7 months of age were collected at arrival (0) and at 4, 7, 14, and 21 days postarrival (DPA). An antigen capture enzyme-linked immunosorbent assay (ELISA) was used to detect concurrent shedding of BCV in fecal and nasal samples. All samples ELISA positive for BCV were matched with an equal number of BCV ELISA-negative samples and analyzed by reverse transcription-polymerase chain reaction (RT-PCR) of the N gene. Paired sera were collected at arrival and 21 DPA and tested for antibodies to BCV using an indirect ELISA. Information on clinical signs, treatments provided, and cattle weights were collected. The overall rates of BCV nasal and fecal shedding were 48% (41/85) and 53% (45/85) by ELISA and 84% (71/85) and 96% (82/85) by RT-PCR, respectively. The peak of BCV nasal and fecal shedding occurred at 4 DPA. Thirty-two cattle (38%) showed concurrent enteric and nasal shedding detected by both tests. Eleven percent of cattle had antibody titers against BCV at 0 DPA and 91% of cattle seroconverted to BCV by 21 DPA. The BCV fecal and nasal shedding detected by ELISA and RT-PCR were statistically correlated with ELISA antibody seroconversion (P < 0.0001); however, BCV fecal and nasal shedding were not significantly related to clinical signs. Seroconversion to BCV was inversely related to average daily weight gains (P < 0.06). Twenty-eight respiratory and 7 enteric BCV strains were isolated from nasal and fetal samples of 32 cattle in HRT-18 cell cultures. These findings confirm the presence of enteric and respiratory BCV infections in feedlot calves. Further studies are needed to elucidate the differences between enteric and respiratory strains of BCV and their role in the bovine respiratory disease complex of feedlot cattle.

Systemic and intestinal antibody secreting cell responses and protection in gnotobiotic pigs immunized orally with attenuated Wa human rotavirus and Wa 2/6-rotavirus-like-particles associated with immunostimulating complexes.

The undesirable side effects and variable efficacy of some oral live rotavirus vaccines in infants have necessitated alternative vaccine approaches. We evaluated a recombinant RFVP2/WaVP6 rotavirus-like-particle (2/6VLP) oral vaccine, using an immunostimulating complex (ISCOM) matrix as adjuvant, in a gnotobiotic (Gn) pig model of human rotavirus (HRV) disease. The 2/6VLPs adhered to the ISCOM-matrix (2/6VLP-ISCOM ) and were antigenic, but they failed to induce protection. However, when combined with attenuated (Att) HRV for oral priming, the 2/6VLP-ISCOM vaccine was effective as a booster and induced partial protection against virulent Wa HRV. The 250 microg 2/6VLP dose was more effective than 100 microg. The highest mean numbers of IgA antibody secreting cells evaluated by ELISPOT in intestinal lymphoid tissues were in pigs receiving AttHRV+2/6VLP-ISCOM or three doses of AttHRV and were associated with the highest protection rates.