Safe Return to Driving After Volar Plating of Distal Radius Fractures.

PURPOSE: A major concern for patients following distal radius fracture fixation is when they can resume driving. This decision has medical, legal, and safety considerations, but there are no evidence-based guidelines to assist the surgeon. The goal of this study was to observe when patients are capable of safely resuming driving following surgical fixation of the distal radius. METHODS: Patients undergoing volar plating of a distal radius fracture were prospectively enrolled. At approximately 2 and 4 weeks after surgery, patients were administered a driving examination on a closed course and given a subjective questionnaire including visual analog scale scores. All basic functions of vehicle operation were evaluated. Successful completion indicated they would pass a driving evaluation. RESULTS: Twenty-three patients were enrolled. Sixteen (69.5%) passed their first attempt (average of 18.4 days from surgery), another 4 (17.4%) passed their second attempt (31.3 days from surgery), and 3 did not complete the second examination. Patients who failed relied too much on their nonsurgical hand, were not able to control the steering wheel with 2 hands, and reported pain and insecurity when using the operative hand. Of those who passed the second attempt, the first failure was universally attributed to pain. Fifteen patients reported a return to independent driving prior to the first examination (average, 11.3 days). Of the 7 who failed, 6 reported they could control the car in an emergency, and 2 reported they would not feel safe with daily driving. Maximum pain while driving on the visual analog scale was 2.4 of 10 among those who failed compared with 1.3 among those who passed. CONCLUSIONS: Most patients could safely return to driving within 3 weeks of surgery. Pain was the primary limiting factor affecting driving ability. Safe return to driving may be warranted within 3 weeks of distal radius volar plate fixation in some patients. Persistent pain is likely the most important obstacle to a safe return to driving. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Prostaglandin E2 protects murine lungs from bleomycin-induced pulmonary fibrosis and lung dysfunction.

Prostaglandin E(2) (PGE(2)) is a lipid mediator that is produced via the metabolism of arachidonic acid by cyclooxygenase enzymes. In the lung, PGE(2) acts as an anti-inflammatory factor and plays an important role in tissue repair processes. Although several studies have examined the role of PGE(2) in the pathogenesis of pulmonary fibrosis in rodents, results have generally been conflicting, and few studies have examined the therapeutic effects of PGE(2) on the accompanying lung dysfunction. In this study, an established model of pulmonary fibrosis was used in which 10-12-wk-old male C57BL/6 mice were administered a single dose (1.0 mg/kg) of bleomycin via oropharyngeal aspiration. To test the role of prostaglandins in this model, mice were dosed, via surgically implanted minipumps, with either vehicle, PGE(2) (1.32 µg/h), or the prostacyclin analog iloprost (0.33 µg/h) beginning 7 days before or 14 days after bleomycin administration. Endpoints assessed at 7 days after bleomycin administration included proinflammatory cytokine levels and measurement of cellular infiltration into the lung. Endpoints assessed at 21 days after bleomycin administration included lung function assessment via invasive (FlexiVent) analysis, cellular infiltration, lung collagen content, and semiquantitative histological analysis of the degree of lung fibrosis (Ashcroft method). Seven days after bleomycin administration, lymphocyte numbers and chemokine C-C motif ligand 2 expression were significantly lower in PGE(2)- and iloprost-treated animals compared with vehicle-treated controls (P < 0.05). When administered 7 days before bleomycin challenge, PGE(2) also protected against the decline in lung static compliance, lung fibrosis, and collagen production that is associated with 3 wk of bleomycin exposure. However, PGE(2) had no therapeutic effect on these parameters when administered 14 days after bleomycin challenge. In summary, PGE(2) prevented the decline in lung static compliance and protected against lung fibrosis when it was administered before bleomycin challenge but had no therapeutic effect when administered after bleomycin challenge.

Isolation of Salmonella enterica serovar Enteritidis from houseflies (Musca domestica) found in rooms containing Salmonella serovar Enteritidis-challenged hens.

Houseflies (Musca domestica) released into rooms containing hens challenged with Salmonella enterica serovar Enteritidis (Salmonella serovar Enteritidis) rapidly became contaminated with Salmonella serovar Enteritidis. Forty to 50% of the flies were contaminated at 48 h, and the percentage increased to 50 to 70% at 4 and 7 days postexposure and then decreased to 30% at day 15. Initial attempts at recovering surface organisms for culture using an aqueous rinse were largely unsuccessful, while cultures of internal contents readily recovered Salmonella serovar Enteritidis. However, when 0.5% detergent was incorporated into the rinse, high recovery levels of bacteria were observed from both external and internal culture regimens, indicating equal distribution of the organism on and in the fly and a tighter interaction of the organism with the host than previously thought. Salmonella serovar Enteritidis was isolated routinely from the fly gut, on rare occasions from the crop, and never from the salivary gland. Feeding contaminated flies to hens resulted in gut colonization of a third of the birds, but release of contaminated flies in a room containing previously unchallenged hens failed to result in colonization of any of the subject birds. These results indicate that flies exposed to an environment containing Salmonella serovar Enteritidis can become colonized with the organism and might serve as a source for transmission of Salmonella serovar Enteritidis within a flock situation.

Colonization of specific regions of the reproductive tract and deposition at different locations inside eggs laid by hens infected with Salmonella enteritidis or Salmonella heidelberg.

Internal contamination of eggs by Salmonella Enteritidis has been a significant source of human illness for several decades and is the focus of a recently proposed U.S. Food and Drug Administration regulatory plan. Salmonella Heidelberg has also been identified as an egg-transmitted human pathogen. The deposition of Salmonella strains inside eggs is apparently a consequence of reproductive tissue colonization in infected laying hens, but the relationship between colonization of specific regions of the reproductive tract and deposition in different locations within eggs is not well documented. In the present study, groups of laying hens were experimentally infected with large oral doses of Salmonella Heidelberg, Salmonella Enteritidis phage type 13a, or Salmonella Enteritidis phage type 14b. For all of these isolates, the overall frequency of ovarian colonization (34.0%) was significantly higher than the frequency of recovery from either the upper (22.9%) or lower (18.1%) regions of the oviduct. No significant differences were observed between the frequencies of Salmonella isolation from egg yolk and albumen (4.0% and 3.3%, respectively). Some significant differences between Salmonella isolates were observed in the frequency of recovery from eggs, but not in the frequency or patterns of recovery from reproductive organs. Accordingly, although the ability of these Salmonella isolates to colonize different regions of the reproductive tract in laying hens was reflected in deposition in both yolk and albumen, there was no indication that any specific affinity of individual isolates for particular regions of this tract produced distinctive patterns of deposition in eggs.

Comparison of Salmonella enterica serovar enteritidis levels in crops of fed or fasted infected hens.

Long-term feed withdrawal has been shown to increase ileocecal intestinal colonization and fecal shedding of Salmonella enterica serovar Enteritidis in challenged hens. Less information is available regarding effects of fasting on crop colonization. Two trials were conducted to compare effects of 14-day feed withdrawal vs. full feed on crop colonization in hens challenged with Salmonella Enteritidis. The levels of Salmonella Enteritidis in the crops of fasted hens were significantly higher than in nonfasted hens on days 3 and 10 and days 3, 9, and 16 postinfection (PI) in trials 1 and 2, respectively. Fecal shedding of Salmonella Enteritidis was significantly increased in the fasted hens on day 10 PI in trial 1. Analysis of crop IgA anti-Salmonella Enteritidis lipopolysaccharide levels in crop lavage samples of hens in trial 1 revealed a humoral response PI in both treatment groups with no significant differences, although peak response for fasted hens occurred 1 wk later. Histologic evaluation of hematoxylin and eosin-stained crop sections from trial 1 birds revealed mild to moderate heterophilic infiltration within the crop lamina propria (LP) or LP and epithelium of nonfasted infected hens at 24 and 96 hr PI. In comparison, heterophils in crops of fasted hens infected at this time point were sparse, indicating a possible diminished heterophil response in the fasted birds. Multifocal areas of tissue inflammation, as indicated by marked heterophil infiltration, with necrosis and sloughing of epithelium, were observed in crops from fasted hens at day 11 PI (14th day of feed withdrawal) but not in the fed groups. This severe heterophilic inflammation was observed in both challenged and nonchallenged fasted hens, suggesting that some factor other than Salmonella Enteritidis was responsible. These results indicate that feed withdrawal can have a dramatic effect on the integrity of the crop and its ultimate response to infection.

Development of a lavage procedure to collect lung secretions from chickens for evaluating respiratory humoral immunity.

Mucosal immunology research has been hampered by the difficulty and labour-intensiveness of collecting samples. This is especially true for sites such as the lung, and the present paper describes a simple method for obtaining samples from this organ in chickens. Following sacrifice, the bird was placed on its back and the trachea was cut and exteriorized. Narrow-diameter tubing, to which a 30 ml syringe was attached, was threaded down the trachea to the bronchi and air was evacuated from the lung. Warm buffer was administered and the lung sample then aspirated, processed and frozen. In the current experiment this sampling system was tested on hens that were challenged with Salmonella Enteritidis. Elevated anti-Salmonella Enteritidis antibody levels in lung from infected hens were observed in significantly more infected hens than non-infected control hens in two trials. The simplicity and utility of this sampling system will make it a useful tool for those laboratories wishing to expand their humoral mucosal immunology capabilities, even for study of non-respiratory pathogens.

Ovoinhibitor in the chicken bursa of Fabricius: identification, isolation, and localization.

A monoclonal antibody (Mab) developed against a partially purified bursal protein extract was found to bind specifically to a single cell type in the cortico-medullary border region of the chicken bursa of Fabricius. These cells were microscopically similar to the bursal secretory dendritic-like cells. A product with an apparent molecular weight of approximately 56 kDa on SDS-polyacrylamide gel electrophoresis was immunopurified from bursal extracts by utilizing this Mab. This product was subjected to peptide digestion and protein sequencing. The two resulting sequences perfectly matched the known sequence of chicken ovoinhibitor. Gene-specific polymerase chain reaction (PCR) primers were designed for the ovoinhibitor, RNA was purified from chicken bursae, and reverse transcription/PCR was performed. Two amplicons with the expected size for ovoinhibitor mRNA were obtained. These data suggest that the gene for ovoinhibitor is expressed in the bursa of Fabricius, and that the bursal secretory dendritic-like cells may be a previously unreported source of ovoinhibitor.

The chicken pituitary expresses an ovoinhibitor-like protein in subpopulations of some, but not all, hormone-producing cell types.

Ovoinhibitor is a serine protease-inhibiting protein that was originally purified from egg whites. It is secreted by the oviduct under the control of estrogen and progesterone and it specifically inhibits serine proteinases such as trypsin and chymotrypsin. During recent attempts to raise monoclonal antibodies (Mabs) against chicken bursa of Fabricius proteins, one Mab was produced that specifically recognized chicken ovoinhibitor. This was the first demonstration of ovoinhibitor in an avian immune organ. We presently report on the expression of an ovoinhibitor-like molecule by the pituitary of the chicken as revealed by immunocytochemistry and RT-PCR. Immunofluorescent dual staining experiments using the mouse anti-ovoinhibitor Mab in conjunction with polyclonal antibodies against various hypophysial hormones revealed partial co-localization of an ovoinhibitor-like molecule with growth hormone (GH), luteinizing hormone (LH), and pro-opiomelanocortin (POMC), in a subset of the respective hormone producing cells. By contrast, no co-localization with prolactin (PRL) could be reliably demonstrated. RT-PCR of hypophysial mRNA using ovoinhibitor gene-specific primers yielded an amplicon that was 20% shorter than predicted on the basis of the published ovoinhibitor sequence. Sequencing revealed that of the represented exons only the central portion was expressed in the pituitary and that both 5' and 3' ends of each exon had been truncated. While expression of ovalbumin-like serine protease inhibitors (serpins) has been previously reported in the rat pituitary, to our knowledge, this is the first report of a Kazal-type serine protease inhibitor in the vertebrate neuroendocrine system.

Reduction of Salmonella Typhimurium in experimentally challenged broilers by nitrate adaptation and chlorate supplementation in drinking water.

The effects of two feed supplements on Salmonella Typhimurium in the ceca of market-age broilers were determined. Broilers orally challenged 6 days before slaughter with a novobiocin- and nalidixic acid-resistant strain of Salmonella Typhimurium were divided into one of four groups (20 birds each). The first group (the control group) received no treatment, the second group received sodium nitrate (SN) treatment (574 mg of NaNO3 per kg of feed), the third group received experimental chlorate product (ECP) treatment (15 mM NaClO3 equivalents), and the fourth group received ECP treatment in combination with SN treatment. The SN treatment was administered via feed for 5 days immediately before slaughter, and ECP was provided via ad libitum access to drinking water for the last 2 days before slaughter. Cecal contents were subjected to bacterial analysis. Significant (P < 0.05) Salmonella Typhimurium reductions (ca. 2 log units) relative to levels for untreated control broilers were observed for broilers receiving ECP in combination with SN. The ECP-only treatment resulted in significant (P < 0.05) reductions (ca. 0.8 log) of Salmonella Typhimurium in trial 2. We hypothesize that increasing Salmonella Typhimurium nitrate reductase activity resulted in increased enzymatic reduction of chlorate to chlorite, with a concomitant decrease in cecal Salmonella Typhimurium levels. On the basis of these results, preadaptation with SN followed by ECP supplementation immediately preharvest could be a potential strategy for the reduction of Salmonella Typhimurium in broilers.

Evaluation of phosphorus loads from Ontario municipal wastewater treatment plants.

Results are presented from an evaluation of the nature and accuracy of phosphorus loads discharged by Ontario municipal wastewater treatment plants into the Great Lakes. Data were examined for the 96 plants treating flows in excess of 4546 m(3)d(-1) for the period 1981 to 1985. For the Lake Erie, Lake Ontario/St. Lawrence River and Upper Great Lakes basins, total basin phosphorus loads were classified according to type of wastewater treatment system, the type of chemical added for phosphorus removal, plant capacity, and sampling frequency. Load estimation techniques were compared using the 1985 daily data from three representative treatment plants. Annual phosphorus loads were compared using the complete data records for the plants and using Monte Carlo techniques to simulate an incomplete data record typical of once per week effluent phosphorus sampling. Potential sources of bias were identified in annual phosphorus load estimates from municipal treatment plants.

The application of infrared measurement techniques to electronic design and testing.

This paper deals with the practical as well as the theoretical aspects of applying ir radiation measurement techniques to the design and testing of electronic components and circuits. Included are descriptions of the various types of instrumentation and their relative merits, general operating guidelines, means for emissivity equalization, component applications, and circuit applications. Limitations are considered for each point of discussion.