Monitoring and surveillance of antimicrobial resistance in microorganisms associated with aquatic animals.

The World Organisation for Animal Health (OIE) Aquatic Animal Health Code recommends that programmes forthe monitoring and surveillance of antimicrobial resistance in microorganisms associated with aquatic animals be initiated by the appropriate authorities. This paper discusses the classes of bacteria to be studied in such programmes and the methods of sample collection to be employed. It also discusses the susceptibility test protocols appropriate for use in such programmes, the interpretive criteria that should be applied to the data they generate and the form in which the output of such programmes should be reported. The authors argue that it is essential that all monitoring and surveillance programmes should employ standardised and internationally harmonised susceptibility test methods to the greatest extent possible. With respect to bacteria capable of infecting aquatic animals, it is recommended that the set of consensus-based standards and guidelines published by the Clinical and Laboratory Standards Institute be adopted as the basis for international harmonisation of test protocols, as they are significantly more developed than any alternatives. It is further recommended that, for the purpose of evaluating antimicrobial resistance trends, such as emerging resistance, the data generated by these protocols should be interpreted by the application of epidemiological cut-off values. However, as yet, internationally agreed cut-off values have been produced for only one species. Thus, for many species, authorities will be obliged to set their own local and laboratory-specific cut-off values. It is recommended that laboratories use a statistical and standardised method of establishing such local cut-off values. Internationally harmonised standard test protocols and interpretive criteria have, to a large extent, been developed to monitor antimicrobial resistance in bacterial species capable of infecting humans. These methods can also be applied to microorganisms capable of infecting humans that are isolated from aquatic animals reared for human consumption or for sale as companion animals.

Endothelial colony-forming cells and mesenchymal stem cells from ECMO circuits of term infants.

OBJECTIVE: Endothelial progenitor cells (EPCs) have been examined in numerous adult diseases and have been suggested as a cellular-based therapy. However, there are no reports describing EPCs being isolated from newborn peripheral blood. STUDY DESIGN: Endothelial colony-forming cells (ECFCs), a subtype of EPCs, were isolated from blood collected from 12 neonatal extracorporeal membrane oxygenation (ECMO) circuits. RESULT: ECFCs were isolated in all samples. We unexpectedly isolated a distinctly different colony of mesenchymal stem cells (MSCs) in seven samples. Both cell types expressed the expected endothelial or mesenchymal cell surface antigens. CONCLUSION: To our knowledge, this is the first report of ECFCs and MSCs isolated from peripheral blood of critically ill term newborns. Both cells types may be mobilized in response to critical illness or to the ECMO circuit. Further studies evaluating the role of stem cells in various newborn conditions are warranted.

Working hypothesis to redefine endothelial progenitor cells.

Since 1997, postnatal vasculogenesis has been purported to be an important mechanism for neoangiogenesis via bone marrow (BM)-derived circulating endothelial progenitor cells (EPCs). Based on this paradigm, EPCs have been extensively studied as biomarkers to assess severity of cardiovascular disease and as a cell-based therapy for several human cardiovascular disorders. In the majority of studies to date, EPCs were identified and enumerated by two primary methodologies; EPCs were obtained and quantified following in vitro cell culture, or EPCs were identified and enumerated by flow cytometry. Both methods have proven controversial. This review will attempt to outline the definition of EPCs from some of the most widely cited published reports in an effort to provide a framework for understanding subsequent studies in this rapidly evolving field. We will focus this review on studies that used cell culture techniques to define EPCs.

'The day of the soft towel?': comparison of the current bed-bathing method with the soft towel bed-bathing method.

The impressions of 200 patients (both medical and surgical) and 200 nursing staff (registered, enrolled and trainee enrolled nurses) in relation to two bed-bathing methods were compared by means of questionnaires and semi-structured interviews. Data regarding costs were obtained from appropriate cost centre managers. The results of the study found the soft towel bed-bathing method to be more cost effective and provide more patient and nurse satisfaction than the current bed-bathing method.

Passy-Muir valve in children with tracheotomy.

INTRODUCTION: Early vocalization and speech production remains a goal in children who require tracheotomy for airway obstruction or chronic ventilation. Although studies document the efficacy of the Passy-Muir valve (PMV) in adults, none have reviewed its efficacy in children. We performed this study to better understand the clinical complexity of its use in children. MATERIALS AND METHODS: Retrospective evaluation of 55 consecutive cases of children with tracheotomy using the PMV. RESULTS: The children ranged in age from 3 days to 18 years at the time of their tracheotomies, and nearly half were 12 months old or younger. Successful use often requires patient and family conditioning. Overall, 52 children out of the 55 who were evaluated as candidates for the PMV tolerated its use. Many required two or more trials prior to the patient and family being comfortable with its use. CONCLUSIONS: The PMV may be used successfully in children with a variety of airway pathologies as well as diverse medical problems. Discussed is the current protocol for the evaluation of the patient and the introduction of the valve.

Maturation of the pediatric tracheostomy stoma: effect on complications.

The pediatric tracheostomy stoma can be matured via a technique that places 4-quadrant sutures from the tracheal cartilage to the dermis. This has the potential of decreasing the risk of accidental decannulation and the formation of granulation tissue. A retrospective analysis of 149 tracheostomies performed between January 1989 and December 1996 was done for the following factors: age, underlying diagnosis, indication for tracheostomy, type of tracheal incision, maturation of stoma, duration of tracheostomy, and early and late (>7 days) complications. Maturation of the stoma was performed in 88 (59.1%) of the 149 tracheostomies. There was an overall complication rate of 21.5% (32/149, not including granulation tissue formation). There were 9 (6.0%) early complications and 23 (15.4%) late complications. The overall incidence of tracheocutaneous fistulas occurred in 11 (11.2%) of the 98 decannulated patients: 6 (10.2%) of the 59 matured stomas and 5 (12.8%) of the 39 nonmatured stomas. Granulation tissue was found on subsequent laryngoscopy in 24 (27.3%) of the 88 matured stomas versus 23 (37.7%) of the 61 nonmatured stomas. There were no tracheostomy-related mortalities. Maturing the tracheostomy stoma resulted in a decreased morbidity from accidental decannulations and did not increase the incidence of tracheocutaneous fistulas or granulation tissue formation.

Chyloperitoneum and abdominal adhesions in a miniature horse.

Chyloperitoneum is a potential cause of colic in horses. Although rare in horses, chyloperitoneum can develop secondary to tearing of mesenteric adhesions and rupture of mesenteric lymphatic vessels. The prognosis for horses with chyloperitoneum depends on the underlying cause and the response to treatment.

Effects of tissue anisotropy on the spectral characteristics of ultrasonic backscatter measured with a clinical imaging system.

In this paper, we report the effects of inherent tissue anisotropy on the spectral properties of backscattered ultrasound when measured with a commercially-available imaging system. We insonified five specimens of bovine tendon immersed in a water tank and rotated in 10 degrees increments while being imaged with a Hewlett-Packard Sonos 1500 system. The backscattered RF signals corresponding to each angle of insonification were digitized and the spectral characteristics of the backscattered ultrasound were determined. The mean anisotropy, defined as the average difference between values at perpendicular and parallel insonification, for band-limited estimates of backscattered power, centroid frequency, upper-band to lower-band power ratio, and upper-band to total-band power ratio were found to be 24.6 +/- 1.1 dB, 142 +/- 27 kHz, 32 +/- 13%, and 22 +/- 5%, respectively (mean +/- SE). The magnitude of each of these backscatter spectral parameters was larger at perpendicular insonification compared with the corresponding values at parallel insonification, consistent with previous measurements of the inherent anisotropy of ultrasonic attenuation and backscatter in tissue.

Echocardiographic quantification of regional left ventricular wall motion with color kinesis.

BACKGROUND: Color kinesis is a new technology for the echocardiographic assessment of left ventricular wall motion based on acoustic quantification. This technique automatically detects endocardial motion in real time by using integrated backscatter data to identify pixel transitions from blood to tissue during systole on a frame-by-frame basis. In this study, we evaluated the feasibility and accuracy of quantitative segmental analysis of color kinesis images to provide objective evaluation of regional systolic endocardial motion. METHODS AND RESULTS: Two-dimensional echocardiograms were obtained in the short-axis and apical four-chamber views in 20 normal subjects and 40 patients with regional wall motion abnormalities. End-systolic color overlays superimposed on the gray scale images were obtained with color kinesis to color encode left ventricular endocardial motion throughout systole on a frame-by-frame basis. These color-encoded images were divided into segments by use of custom software. In each segment, pixels of different colors were counted and displayed as stacked histograms reflecting the magnitude and timing of regional endocardial excursion. In normal subjects, histograms were found to be highly consistent and reproducible. The patterns of contraction obtained in normal subjects were used as a reference for the objective automated interpretation of regional wall motion abnormalities, defined as deviations from this pattern. The variability in the echocardiographic interpretation of wall motion between two experienced readers was similar to the diagnostic variability between the consensus of the two readers and the automated interpretation. CONCLUSIONS: Color kinesis is a promising new tool that may be used clinically to improve the qualitative and quantitative evaluation of spatial and temporal aspects of global and regional wall motion. In this initial study, segmental analysis of color kinesis images provided accurate, automated, and quantitative diagnosis of regional wall motion abnormalities.

Automated, on-line quantification of left ventricular dimensions and function by echocardiography with backscatter imaging and lateral gain compensation.

To provide on-line quantification of left ventricular cavity dimensions and function by echocardiography 60 control subjects and 10 patients with cardiac dysfunction were studied. A novel, ultrasound imaging system was used which was developed to detect and track, in real time, ventricular endocardial blood boundaries based on quantitative assessment of acoustic properties of tissue. In addition, lateral gain compensation, a robust and novel image enhancement procedure, was used to provide instantaneous measurement and display of cavity areas and functional indexes on a beat-by-beat basis within regions of interest drawn around the blood pool cavity. In control subjects, short-axis end-diastolic area averaged 13.1 +/- 3.7 cm2 (SD), end-systolic area 5.9 +/- 2.7 cm2, and fractional area change 55.6 +/- 11.2%. Apical views yielded corresponding values of 23.8 +/- 4.5 cm2, 15.5 +/- 3.4 cm2 and 34.7 +/- 7.8%. Instantaneous peak rate of cavity area change approximated 50 cm2/s in systole and 60 cm2/s in diastole in each view. Serial measurements of area and functional index were reproducible over intervals of 2 to 3 weeks. Patients with dilated ventricles exhibited average apical view area values of 49.1 +/- 6.1 cm2 and 43.1 +/- 4.9 cm2 in diastole and systole with a fractional area change of 12.2 +/- 3.0%. Thus, results with on-line echocardiographic backscatter imaging-assisted automated edge detection are reproducible and capable of delineating cardiac dysfunction conveniently, promptly and serially at the bedside.

Use of an in vitro haemolysis test to predict tissue irritancy in an intramuscular formulation.

As part of a drug development program, an in vitro haemolysis test has been used to predict the in vivo muscle tissue irritancy of intramuscular (i.m.) formulations of a new drug entity. Solutions of lactic acid, polyvinylpyrrolidone (PVP) 12PF and two commercial injections were also included in the study. The results indicated that the test was able to differentiate formulations in terms of haemolytic potential and the correlation between the haemolysis test results and in vivo intramuscular irritancy studies indicated that the test may be used to screen formulations for potential tissue irritancy prior to in vivo evaluation.