Molecular epidemiology of Escherichia coli causing bloodstream infections in a centralized Canadian region: a population-based surveillance study.

OBJECTIVES: Escherichia coli is a leading cause of bloodstream infections worldwide, and is responsible for substantial patient morbidity, mortality and healthcare expenditure. Understanding the molecular epidemiology of E. coli will aid in designing superior treatment and prevention strategies. METHODS: We undertook a population-based surveillance study describing the clinical factors, susceptibility patterns, incidence rates and geographical distribution of sequence types (STs) among E. coli isolates (n = 686) causing incident bloodstream infections in a centralized Canadian region during 2016. STs were identified using a seven-single-nucleotide-polymorphism quantitative PCR (n = 422) and sequencing of certain house-keeping genes (n = 249). RESULTS: The annual population incidence rate of E. coli bloodstream infections was 48.8/100 000 patient years, and five dominant clones (ST131, ST73, ST69, ST95 and ST1193) accounting for 55% (378/686) of the population were identified, each with a specific geographical distribution within Calgary. ST131 was the most common (overall incidence rate of 10.4/100 000 patient years), an antimicrobial-resistant (AMR) clone affecting mainly the elderly and the very young. ST131 was common among residents in long-term care with an incidence rate of 312.5/100 000 patient years. ST73 was associated with community infections in the elderly, while ST69 and ST95 had increased incidence rates among females. ST1193 was the second most AMR clone and was associated with bloodstream infections in elderly males. CONCLUSIONS: This study showed that E. coli clones have unique characteristics in a well-defined human population. The elimination of ST131 would substantially decrease the overall incidence rate and AMR burden among E. coli bloodstream infections in the Calgary region, leading to considerable public health benefits.

The cellular perspective on mammary gland development: stem/progenitor cells and beyond.

Study of the mammary gland at the stem cell level is necessary for understanding mammary gland development. Knowledge of mammary gland development and growth is the first step toward formulating strategies to improve milk production. The success of these strategies requires an understanding of the dynamics of adult stem cells and their progeny in the development of the bovine mammary gland. The stem cell lineage pathway begins with adult stem cells and ends with the production of terminally differentiated cells. The progression of adult stem cells along the mammary gland stem cell lineage pathway requires the coordination of many events. One important event in this process is cell differentiation. This differentiation process evolves with a gradient appearance of cell organelles progressing from stem cells to terminally differentiated cells. To dissect differentiation, mechanisms that regulate stem cells to differentiate toward a particular cell fate must be identified. Ultrastructural characteristics assist in distinguishing cells in various stages of differentiation in the mammary gland cell lineage pathway. Cells in the lineage pathway can become either epithelial cells or myoepithelial cells. Epithelial cells function in the production and secretion of milk, whereas myoepithelial cells assist epithelial cells in milk secretion. This review focuses on current concepts regarding adult stem cells and the recent progress on bovine mammary gland stem/progenitor cell development and differentiation. Multistep strategies that incorporate manipulation of the mechanisms influencing lineage choices in the mammary gland will produce beneficial effects on mammary gland development and milk production.

A comparative study of histological conditions suitable for both immunofluorescence and in situ hybridization in the detection of Herpesvirus and its antigens in chicken tissues.

Our objective was to identify an optimal single set of conditions for use in both indirect immunofluorescence assays (IFA) and in situ hybridization (ISH) to detect viral proteins and nucleic acids in avian lymphoid and neural tissues. Various fixatives were evaluated for use with IFA to detect turkey Herpesvirus (HVT) glycoprotein B (gB) and ISH to identify HVT mRNA in chicken tissues. A precipitating fixative (acetone) was compared to crosslinking fixatives [buffered glutaraldehyde-picric acid (BGPA), 10% formalin, and 4% paraformaldehyde] for both IFA and ISH using spleen, thymus, bursa, sciatic plexus, and brachial plexus of 28-day-old chickens. Four percent paraformaldehyde was found to be the optimal fixative for preservation of all chicken tissues examined with both IFA and ISH. Glass slide preparation, incubation temperatures, and tissue processing were each individually evaluated for ISH and IFA. Silylated slides provided the best retention of tissue sections for both procedures. For IFA, 37 degrees C was the ideal incubation temperature tested, whereas the optimal incubation temperature tested for ISH was 47 degrees C. Of the blocking agents compared, Evans blue dye prevented background fluorescence to a greater extent than either calf serum or bovine serum albumin. These findings provide a technical basis for investigations into various aspects of the molecular pathology of avian diseases.

Characterization of eae+ Escherichia coli isolated from healthy and diarrheic calves.

Strains of Escherichia coli from 101 healthy and 114 diarrheic calves were screened by PCR for the eae (intimin) gene and Shiga toxin genes (stx). Each eae+ and eae/stx+ strain was examined for antimicrobial susceptibility, enterohemolysin activity, and the somatic O antigen was determined. An immunoassay was used to detect Shiga toxin antigens for the eae/stx+ E. coli. Significantly more (p = 0.005) of the healthy calves carried eae+ and eae/stx+ E. coli in their feces when compared to strains from diarrheic calves. Moreover, Shiga toxin antigens were detected significantly more (p = 0.001) often among the eae/stx+ strains from healthy calves when compared to eae/stx+ strains from diarrheic calves. However, significantly more (p = 0.001) of the eae+ and eae/stx+ strains from diarrheic calves were resistant to at least one of the antimicrobials tested, and the strains from diarrheic calves had a significantly (p = 0.05) higher rate of antimicrobial resistance to at least two different antimicrobial classes. No significant difference (p> or =0.05) was detected among the eae+ and eae/stx+ strains from healthy and diarrheic calves for enterohemolysin production. Serogroups O-negative, O5, O26, and O111 were predominate among both healthy and diarrheic calves.

Identification and localization of glycoprotein B expression in lymphoid tissues of chickens infected with turkey herpesvirus.

One-day-old chickens were inoculated with turkey herpesvirus (HVT). Using an indirect immunofluorescence assay with a monoclonal antibody against HVT glycoprotein B (gB), we determined the course of productive HVT infection in peripheral blood mononuclear cells (PBMCs), spleen, thymus, and bursa. PBMCs were examined from days 4 through 35 postinfection (PI). The spleen, thymus, and bursa were examined from 21 through 70 days PI. Although productive infection in PBMCs was detected at 4 to 12 days PI, it ended by 14 days PI. Splenic cells expressed gB at 21, 28, 35, and 70 days PI, whereas the thymus was positive for gB expression at 21 and 35 days PI. The bursa was never positive for gB expression. At 21, 28, 35, and 70 days PI, plaque formation after co-cultivation of PBMCs with chicken embryo fibroblasts indicated the presence of HVT in infected chickens by co-cultivation assays. On the basis of indirect immunofluorescence assay, gB expression in the spleen and thymus indicates a productive HVT infection in chickens.

Latent turkey herpesvirus infection in lymphoid, nervous, and feather tissues of chickens.

In earlier studies, we found that a late gene product, glycoprotein B (gB) was highly expressed in lymphoid tissues of chickens inoculated with turkey herpesvirus (HVT). The objectives of the present study were twofold. First, we wanted to expand on our previous research and determine if gB expression declines or disappears during later time periods of HVT infection. Second, we wanted to correlate gB expression with presence of HVT, i.e. if gB expression is absent, can HVT still be detected? Fifteen 1-day-old chicks were inoculated by intraperitoneal inoculation with 2000 plaque forming units of strain FC126 HVT. Thymus, spleen, bursa, brachial plexus, sciatic plexus, and feather tips were harvested at 21, 28, 35, 70, and 105 days postinoculation (PI). Brachial plexus and sciatic plexus were examined at 21, 28, and 35 days PI, and feather tips were examined at 21 and 28 days PI. An indirect immunofluorescence assay was used to detect HVT gB expression, and an in situ hybridization assay was used to detect HVT. At 21 days PI, gB expression was present in the thymus, spleen, and bursa. At 28 and 35 days PI, gB expression was detected in the thymus and spleen. At 70 days PI, gB expression was detected only in the spleen, and at 105 days PI, gB expression was not detected in any of the lymphoid tissue (thymus, spleen, or bursa). gB expression was not detected in the brachial plexus, sciatic plexus, or feather tips at any of the five time points. The bursa contained HVT only at 21 and 28 days PI. However, HVT was demonstrated in all other tissues from 21 to 105 days PI. Progression from a productive HVT infection to a latent HVT infection results in the loss of gB expression. Throughout this progression, a region of the HVT genome can be detected by appropriate methods.

Determinants of patient satisfaction with outpatient surgery.

To help understand the determinants of patient satisfaction following outpatient surgery, the authors developed a written survey instrument and administered it to more than 200 patients. The significant predictors of overall satisfaction were the courtesy of the staff and clinical quality. Overall satisfaction was also found to be a significant predictor of intent to recommend.

Tissue-specific restriction of latent turkey HVT transcription.

Using in situ hybridization, latent turkey herpesvirus (HVT) transcription was examined in lymphoid and/or nonlymphoid tissues. Blood samples were taken for virus isolation from chickens at 7 and 240 days post infection (PI) representing time points for productive and latent turkey herpesvirus infections, respectively. Spleen, thymus, sciatic and brachial nerves from infected chickens were analyzed for latent HVT transcription and HVT glycoprotein B (gB) expression at 240 days PI. Using indirect immunofluorescence, HVT gB expression was not detected in any tissues examined at 240 days PI. HVT genomic fragments from a HVT BamHI library were used as probes in in situ hybridization assays. In the spleen, thymus, sciatic and brachial nerves, latent HVT transcription occurred from the repeat regions flanking the unique long region (TRL and IRL). However, fine-mapping of this region revealed a difference in latent HVT transcriptional pattern. A SmaI map of the HVT BamHI-F fragment was made to further fine-map latent HVT transcription. A 1.6 kbp SmaI subfragment hybridized to cells infected with latent HVT in the spleen and thymus. However, the 1.6 kbp SmaI subfragment did not hybridize to cells of the brachial or sciatic nerves. In addition, a 2.0 kbp SmaI subfragment hybridized to cells in the thymus but not in the spleen, sciatic or brachial nerves. The above results suggest that latent turkey herpesvirus exhibits tissue-specific transcription.

A comparison study of vecuronium bromide and atracurium besylate for rapid sequence induction.

Rapid sequence induction is necessary in emergency surgical operations to lessen the chance of aspiration of stomach contents. Succinylcholine usually is the relaxant of choice, because of its rapid onset. However, succinylcholine has side effects which may result in potentially life-threatening conditions. The purpose of this study was to compare two short-acting non-depolarizing muscle relaxants-vecuronium and atracurium, using the priming principle, with a depolarizing muscle relaxant, succinylcholine. The comparison may determine if a more suitable method for rapid sequence induction can be identified. Conditions at intubation and at the time to 80-90% neuromuscular blockade were evaluated. Subjects were intubated when the train of four revealed an 80-90% twitch depression. In Group I, the control group using succinylcholine, the mean time to 80-90% neuromuscular block was 74.8 seconds. In Group II subjects, who had received vecuronium, the mean time was 149.4 seconds. Subject in Group III, who received atracurium, had a mean time of 163.7 seconds. There was statistical significance within all three groups (ANOVA, p less than 0.01). Group I subjects showed a significantly faster time to 80-90% neuromuscular block when compared with subjects in Group II and III, but no difference in the time to 80-90% block was revealed between Group II and Group III subjects. Conditions for intubation at 80-90% neuromuscular blockade were the same for all three groups. It was concluded that the administration of vecuronium and atracurium using the priming principle did not allow onset times similar to succinylcholine and that the intubating conditions were similar among all three groups at 80-90% neuromuscular blockade.

Comparison of droperidol 0.01 mg/kg and 0.005 mg/kg as a premedication in the prevention of nausea and vomiting in the outpatient for laparoscopy.

Patients undergoing outpatient laparoscopy and general anesthesia have a high incidence of postoperative nausea and vomiting. It is essential that anesthesia techniques accommodate the special needs of these outpatients. Droperidol is an effective antiemetic but larger doses above 1-1.25 mg may cause unwanted side effects which may prolong recovery and discharge. The current trend is to decrease the dose of droperidol to prevent side effects while still retaining the antiemetic properties. This experimental study compares droperidol 0.010 mg/kg and 0.005 mg/kg as a premedication for the prevention of nausea and vomiting in 32 female outpatients undergoing laparoscopy and general anesthesia. The patients were randomized into two groups. Group I received droperidol 0.010 mg/kg and Group II received 0.005 mg/kg as a preoperative antiemetic in double-blind fashion. Both groups received the same anesthetic for induction and maintenance of anesthesia. The patients were observed in the postanesthesia room for the incidence of nausea and vomiting. They were transported to the outpatient department and were also observed for nausea and vomiting. The t-test was used to show that there were no significant differences between groups in population characteristics. Chi-square analysis was used to determine statistical significance in the incidence of nausea or vomiting between the two groups. Analysis showed there was no statistically significant difference in the incidence of nausea or vomiting in the postanesthesia room or the outpatient department, although there was a significant clinical difference between the groups especially in the incidence of nausea in the outpatient department.(ABSTRACT TRUNCATED AT 250 WORDS)

AANA Journal course: new technologies in anesthesia: update for nurse anesthetists--alternatives for postoperative pain management.

Conventional intramuscular or intravenous opioid therapy provides less than optimal postoperative analgesia in many situations. Recent advances allow a more rational administration of narcotic agents and a more individualized approach to patient analgesic requirements. In this lesson, current concepts of pain physiology will be covered, including afferent pain pathways, the descending modulation of nociception traffic and the neurohumoral stress response. A discussion of selected alternatives to traditional postoperative pain management techniques will be presented. Descriptions of spinal opioid therapy and patient-controlled analgesia (PCA) will include the pharmacology and complications of these techniques. The potential for idealized postoperative pain management to alter the neurohumoral stress response to tissue injury, and thereby affect perioperative outcome, will be explored.

Central anticholinergic syndrome in a pediatric patient following transdermal scopolamine patch placement.

A 9-year-old child was admitted to the hospital with congenital left ureteropelvic junction obstruction with massive left pyelocaliectasis and underwent dismembered pyeloplasty of the left kidney under general anesthesia without complications. Postoperatively, the child was placed on patient-controlled analgesia, with morphine as the drug of choice. The patient was discharged to the ward with adequate pain control and no complaints of nausea or vomiting. Once on the ward, a transdermal scopolamine patch was placed for nausea and vomiting. More than 24 hours after patch placement, the child experienced central anticholinergic syndrome (CAS) with hallucinations and incontinence. The scopolamine patch was promptly removed, and all symptoms of CAS rapidly ceased. A transdermal scopolamine patch should not be used in the pediatric population, and with extreme caution in the elderly. Treatment of CAS includes prompt removal of the patch, cleansing of the area, and possible physostigmine administration.

The recovery of horses from inhalant anesthesia: a comparison of halothane and isoflurane.

OBJECTIVE: Recovery is one of the more precarious phases of equine general anesthesia. The quality and rate of recovery of horses from halothane and isoflurane anesthesia were compared to determine differences in the characteristics of emergence from these commonly used inhalant anesthetics. EXPERIMENTAL DESIGN: Prospective, randomized blinded clinical trial. SAMPLE POPULATION: A total of 96 Thoroughbred and 3 Standardbred racehorses admitted for elective distal forelimb arthroscopy. METHODS: All horses were premedicated with intravenous xylazine, induced with guaifenesin and ketamine, and maintained on a large animal circle system fitted with an out of the circle, agent specific vaporizer. Recoveries were managed by a blinded scorer with a standardized protocol. A 10 category scoring system was used to assess each horse's overall attitude, purposeful activity, muscle coordination, strength and balance from the time of arrival in recovery to standing. Times to extubation, sternal recumbency and standing were recorded. Median recovery scores and mean times to extubation, sternal and standing were compared using the Mann-Whitney U test and student's t test, respectively. RESULTS: The median score for horses recovering from halothane was lower (20.0; range, 10 to 57) than that for horses recovering from isoflurane (27.5; range, 10 to 55). Horses in the two groups were extubated at similar mean times (halothane, 11.3 +/- 5.5 and isoflurane, 9.5 +/- 5.2 minutes) but horses recovering from isoflurane achieved sternal recumbency (halothane, 37.7 +/- 12.1 and isoflurane, 24.7 +/- 8.8 minutes) and stood (halothane, 40.6 +/- 12.9 and isoflurane, 27.6 +/- 9.6 minutes) sooner than those recovering from halothane. CONCLUSIONS: The recovery of horses from isoflurane anesthesia was more rapid but less composed than that from halothane. CLINICAL RELEVANCE: The quality of recovery following isoflurane was worse than after halothane anesthesia using the criteria chosen for this study. However, the range of recovery scores was similar for both groups and all horses recovered without significant injury.

Equine post-anesthetic lameness. A retrospective study.

The incidence of post-anesthetic lameness in 655 horses undergoing 733 anesthetic episodes over a 3 year period was 6.4%. Nineteen factors previously reported or proposed to play a role in the development of post-anesthetic lameness were evaluated statistically. Only hypotension and the duration of the anesthetic period were significant factors.