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PubMed2005

Measuring fluctuating asymmetry in fattening rabbits: a valid indicator of performance and housing quality?

Fluctuating asymmetry (FA) has been advocated as the preferred measure of developmental instability and a reliable indicator of the quality of an animal (performance/fitness) and of its environment during its growing life. Empirical studies, however, are too scant or equivocal to consider this assumption adequately validated, which is partly due to the lack of a robust methodological framework for collecting and analyzing FA data. Therefore, we conducted an experiment in which 306 weaned rabbits were housed either in welfare-friendly pens (n = 6) or barren pens (n = 6). The size of both types of pen was similar (1.91 m2), but the welfare-friendly pens were equipped with suitable enrichment material (gnawing stick, elevated platform, and hiding box) and were stocked with one-half of the number of rabbits compared with the barren pens (17 vs. 34 rabbits per pen). Performance data (BW gain, ADFI, and G:F) were collected every 14 d. After slaughter (d 63 to 72), we measured twice the left- and right-hand side of 11 presumed bilateral traits on intact carcasses and 50 traits on fleshed bones. Using a stringent decision process, an optimal combination of morphological traits for estimating FA in fattening rabbits was determined. This combination consisted of five traits (fleshed bones) that showed no directional asymmetry or antisymmetry and showed a high level of FA relative to the measurement error; also, these traits were not correlated in their signed FA values. Measurements on intact carcasses seemed inappropriate for estimating FA. Using this robust FA measuring protocol, rabbits housed in the welfare-friendly pens were less asymmetric than were rabbits from the barren pens. Except for a greater daily BW gain in the welfare-friendly pens during the first 14 d after weaning, there were no effects of housing conditions on performance traits. The FA was negatively correlated with BW gain in rabbits from the barren pens, whereas in the welfare-friendly pens, there was no correlation. These results support the application of FA as an indicator of animal welfare and performance; however, FA seems to be a more reliable estimator of the underlying developmental instability when living conditions are suboptimal.

Animal Welfare↗
PubMed2002

T-lymphocyte epitope identification and their use in vaccine development for HIV-1.

Cellular immune responses mediated by CD8+ cytotoxic T-lymphocytes (CTL) and CD4+ helper T-lymphocytes (HTL) are needed to effectively control and clear many viral pathogens, including HIV-1. Thus, vaccines for HIV-1 capable of inducing CTL and HTL responses are now the focus of multiple academic and industry-based research and development programs. The use of defined, minimal CTL and HTL epitopes in vaccines has several potential advantages. Firstly, it is possible to use epitopes that are conserved thus targeting the majority of viral variants within a given clade or across clades. Secondly, epitopes from multiple viral structural or accessory gene products can be included in vaccines, which supports the induction cellular immune responses with significant breadth. Finally, dominance relationships between epitopes can be altered to increase immune recognition of subdominant epitopes. HTL and CTL epitopes from HIV-1 have recently been identified and characterized in numbers that are large enough to support their use in experimental vaccines. Initial studies with prototype DNA vaccines encoding epitopes indicate the need to include intracellular targeting sequences, to direct the encoded gene products to different cellular compartments, and amino acid spacer sequences between epitopes to optimize the processing, and subsequent presentation, of individual epitopes. Vaccines composed of CTL or HTL epitopes are now being developed for clinical testing.

AIDS Vaccines↗
PubMed1994

Hypochlorite solution as a decontaminant in sulfur mustard contaminated skin defects in the euthymic hairless guinea pig.

Hypochlorite solutions are thought to be efficacious when used to topically decontaminate intact skin. However, few studies have examined the efficacy of decontamination of chemically contaminated wounds. Therefore, we compared the decontamination efficacy of sodium hypochlorite (0.5% and 2.5% solutions), calcium hypochlorite (0.5% and 2.5% solutions) and sterile water to untreated controls in wounds exposed to sulfur mustard (HD). Anesthetized euthymic hairless guinea pigs (EHGP) (n = 6) were exposed to 20 mg/kg (approximately 0.4 LD50) HD in a full-thickness 8 mm surgical biopsy skin defect (i.e., wound). Each animal was subsequently decontaminated, after a two-minute intra-wound exposure to liquid HD, with nothing or one of the decontamination solutions. Decontamination efficacy was determined by the visual grading of the HD-traumatized wound lesion and by comparison of the expected HD-induced leukocyte suppression. Leukocyte suppression was inconsistent in all animals; therefore, the visual grading was the only viable evaluation method. No significant differences were observed among wounds decontaminated with any of the solutions. However, the skin surrounding non-decontaminated (but exposed) control animals showed the least visual pathology. The lesions induced following decontamination are presumed to be due to the mechanical flushing of HD onto the peri-lesional skin, or by chemical damage induced by the solution, or HD-solution interaction. Further studies are required to best delineate the optimal decontamination process for HD contaminated wounds.

Analysis of Variance↗
PubMedDate not supplied

An educational hypertext system supporting radiographic image quality.

Understanding the physical and technical factors affecting image characteristics is an essential learning task in the process of optimizing radiographic image quality. The goal of the present effort is the design of a stand-alone software application acting as an educational aid to radiology residents and radiographers. The application is organized in three modules, each one offering a different approach to the learning task. The core of the system is a hypertext database management system composed of text, digitized radiographs, graphics and animations. User orientation, linking, indexing, and annotation are some of the facilities offered in pursuing topics of interest.

Computer Graphics↗
PubMed1990

Developmental changes in glutamine transport by rat jejunal basolateral membrane vesicles.

The ontogeny of glutamine uptake by jejunal basolateral membrane vesicles (BLMV) was studied in suckling and weanling rats and the results were compared with adult rats. Glutamine uptake was found to represent a transport into an osmotically active space and not mere binding to the membrane surface. Temperature dependency indicated a carrier-mediated process with optimal pH of 7.0. Transport of glutamine was Na+ (out greater than in) gradient dependent with a distinct "overshoot" phenomenon. The magnitude of the overshoot was higher in suckling compared with weanling rats. The uptake kinetics and inhibition profile indicated the existence of two major transport pathways. A Na(+)-dependent system correlated with System A showed tolerance to System N and System ASC substrates, and a Na(+)-independent system similar to the classical L system that favors leucine and BCH. The Vmax for the Na(+)-dependent system was higher in suckling compared with weanling and adult rats. The Vmax for the Na(+)-dependent system was 0.86 +/- 0.17, 0.64 +/- 0.8, and 0.41 +/- 0.9 nmol.mg protein-1.10 sec-1 for suckling, weanling, and adult rats, respectively. The Vmax for the Na(+)-independent system was 0.68 +/- 0.08, 0.50 +/- 0.03, and 0.24 +/- 0.03 nmol.mg protein-1.10 sec-1 for suckling, weanling, and adult rats, respectively. We conclude that glutamine uptake undergoes developmental changes consistent with more activity and/or number of glutamine transporters during periods of active cellular proliferation and differentiation.

Aging↗
PubMed2004

Reciprocal influences of attentional focus on postural and suprapostural task performance.

The authors examined the influence that attentional focus on either a postural or a suprapostural task had on the performance of each task. Participants (N = 32) stood on an inflated rubber disk and held a pole horizontally. All participants performed under 4 attentional focus conditions: external (disk) or internal (feet) focus on the postural task, and external (pole) or internal (hands) focus on the suprapostural task. Compared with internal focuses, external focuses on either task resulted in similar and reduced postural sway. Response frequency on each task increased when participants focused on the respective task. Finally, an external focus on either task produced higher frequencies of responding on the suprapostural task. The authors conclude that suprapostural task goals have a stronger influence on postural control than vice versa, reflecting the propensity of the motor system to optimize control processes on the basis of the desired movement effect.

Attention↗
PubMed2001

[Automated analysis for determination of PCBs in fish].

An automated analytical method for determination of polychlorinated biphenyls (PCBs) in fish was developed using supercritical fluid extraction (SFE) in combination with an automated sample preparation instrument (Prep) and GC/MS. By incorporating basic alumina with the sample in the extraction process, and optimizing the amount of carbon dioxide used, fish lipid was selectively reduced. The extract was cleaned up on a Florisil cartridge with Prep. The method was evaluated using naturally contaminated tissues and by comparison of automated analytical method results with those obtained by the conventional method. Mean recovery of PCBs from 3 kinds of fish including hairtail, mackerel and yellowtail were 69.8%, 90.2% and 81.1%, respectively. This method is less laborious and requires far less organic solvent than the conventional method, but produced comparable results.

Animals↗
PubMed2005

Prosodic cues for morphological complexity: the case of Dutch plural nouns.

It has recently been shown that listeners use systematic differences in vowel length and intonation to resolve ambiguities between onset-matched simple words (Davis, Marslen-Wilson, & Gaskell, 2002; Salverda, Dahan, & McQueen, 2003). The present study shows that listeners also use prosodic information in the speech signal to optimize morphological processing. The precise acoustic realization of the stem provides crucial information to the listener about the morphological context in which the stem appears and attenuates the competition between stored inflectional variants. We argue that listeners are able to make use of prosodic information, even though the speech signal is highly variable within and between speakers, by virtue of the relative invariance of the duration of the onset. This provides listeners with a baseline against which the durational cues in a vowel and a coda can be evaluated. Furthermore, our experiments provide evidence for item-specific prosodic effects.

Cues↗
PubMed2005

An early electrophysiological response associated with expertise in letter perception.

Expertise with print is likely to optimize visual processes for recognizing characters of a familiar writing system. Although brain activations have been identified for words and letter strings in contrast with other stimuli, relatively little work has focused on the neural basis of single-letter perception. English readers and Chinese-English bilinguals participated in an ERP study and performed a 1-back identity judgment on Roman letters, Chinese characters, pseudofonts, and their string versions. The Chinese-English bilinguals showed an enhanced N170 for both Roman letters and Chinese characters relative to pseudofonts. For the non-Chinese readers, the N170 amplitude was larger for Roman letters relative to Chinese characters and pseudofonts. Our results suggest that changes in relatively early visual processes underlie expert letter perception.

Adult↗
PubMed2006

Development of an integrated prostate cancer research information system.

BACKGROUND: In this article, we describe the design and implementation of a comprehensive prostate cancer database developed to collect, store, and access clinical, treatment, and outcomes data for research and clinical care. PATIENTS AND METHODS: The Prostate Cancer Clinical Research Information System is a relational database. Data are entered from multiple sources, including medical records, institutional laboratory, patient registration, pharmacy systems, and clinician forms. The history, design, and operational characteristics of the database are described. Issues regarding necessary staffing and funding of databases are reviewed. RESULTS: Four thousand two hundred forty-six patients have information in the Prostate Cancer Clinical Research Information System. Mean age of patients is 62 years, and 89% are white. Seventy-one percent of patients presented at diagnosis with T1 or T2 disease, and 78% had biopsy Gleason scores of <or=7, 8-10 in 18%. Median prostate-specific antigen level at diagnosis was 7 ng/mL, and 77% of patients presented with increased prostate-specific antigen as a trigger symptom. Sixty-four percent of patients presented to our clinic having had no previous treatment for prostate cancer. The majority of approached patients provided consent for collection of clinical data, blood, and tissue. Quality control assessments demonstrate high levels of concordance among data entry personnel. CONCLUSION: Clinical databases are difficult to implement and maintain; however, they represent a valuable resource, particularly when linked to blood and tissue banks. Elements needed for a successful clinical database include engagement of clinicians, utility for research, and the ability to integrate with legacy systems. As cancer centers develop such databases, lessons learned from each experience should be shared in order to optimize the process.

Adult↗
PubMed2005

Toward validation of process criteria for high-pressure processing of orange juice with predictive models.

Mathematical models were developed to predict time to inactivation (TTI) by high-pressure processing of Salmonella in Australian Valencia orange juice (pH 4.3) and navel orange juice (pH 3.7) as a function of pressure magnitude (300 to 600 MPa) and inoculum level (3 to 7 log CFU/ml). For each model, the TTI was found to increase with increasing inoculum level and decrease with increasing pressure magnitude. The U.S. Food and Drug Administration Juice Hazard Analysis and Critical Control Point Regulation requires fruit juice processors to include control measures that produce a 5-log reduction of the pertinent microorganism of public health significance in the juice. To achieve a 5-log reduction of Salmonella in navel orange juice at 20 degrees C, the models predicted hold times of 198, 19, and 5 s at 300, 450, and 600 MPa, respectively. In Valencia orange juice at 20 degrees C, a 5-log reduction of Salmonella was achieved in 369, 25, and 5 s at 300, 450, and 600 MPa, respectively. At pressures below 400 MPa, Salmonella was more sensitive to pressure in the more acidic conditions of the navel orange juice and TTIs were shorter. At higher pressures, little difference in the predicted TTI was observed. Refrigerated storage (4 degrees C) of inoculated navel orange juice treated at selected pressure/time/inoculum combinations showed that under conditions in which viable Salmonella was recovered immediately after high-pressure processing, pressure-treated Salmonella was susceptible to the acidic environment of orange juice or to chill storage temperature. These TTI models can assist fruit juice processors in selecting processing criteria to achieve an appropriate performance criterion with regard to the reduction of Salmonella in orange juice, while allowing for processing flexibility and optimization of high-pressure juice processing.

Beverages↗
PubMed2005

Clinical and ethical implications of genetic counselling in familial adenomatous polyposis.

The association of specific genetic disturbances with the development of hereditary cancer helps us to understand the risk of suffering from it, the possibility of an earlier diagnosis, and the treatment and prevention of this disease. Familial adenomatous polyposis (FAP) is a pre-neoplastic syndrome characterized by the presence of hundreds of adenomatous polyps in the colon, which develop into a carcinoma. FAP can be diagnosed using sequencing techniques to detect mutations in the germinal line of the APC (adenomatous polyposis coli) gene. The genetic diagnostic approach in families with FAP, previously followed up in the Gastrointestinal Clinic, has both advantages and disadvantages, and places us nearer the disease and patient. Disclosing the results of this genetic test entails relevant problems in clinical practice, which affect the health field and raise legal and ethical issues, along with the familial, occupational, and social implications that knowing the genetic status can have on the patient. Genetic analysis is rare in normal clinical practice, which involves errors in the interpretation of the results obtained, and during the process of genetic counselling. Specialized multidisciplinary units are necessary for the management of patients with FAP undergoing analysis and appropriate genetic counselling, thus providing an individualized service. The creation of FAP registers and protocols for this healthcare process should optimize the management of these patients and their families.

Adenomatous Polyposis Coli↗
PubMed1998

Diagnosis of Helicobacter pylori: invasive methods.

The methods which require endoscopy for the examination of the gastric mucosa are called invasive (direct) methods. Several tests can be performed on the gastric mucosa obtained by endoscopy: Rapid urease test, histology, smear (cytology), culture and polymerase chain reaction. A combination of at least two tests with high sensitivity and specificity is recommended for clinical trials, and, when possible, for clinical management of patients. In clinical practice the invasive methods should be carried out only in those patients to be treated with eradication regimes. All invasive methods rely on gastric biopsy samples. Therefore, the specimens should be taken under optimal conditions. Several factors guide the site and the number of biopsy specimens for identification of Helicobacter pylori infection. In pre-treatment diagnosis, the biopsies should be taken from the distal antrum (2 cm from the pylorus). The number required depends on the diagnostic method used: in Helicobacter pylori eradicated patients the same number of biopsies for histology and culture should be taken from the antrum and corpus. The sensitivity and specificity of the Rapid urease test varies from 80-90% the results are known very quickly and the cost is very low. The maximal accuracy of histology is obtained with: an optimal specimen processing, an adequate staining and an experienced observer. This method of biopsy processing facilitates the identification of Helicobacter pylori which is commonly located on the superficial and foveolar epithelium. Sensitivity depends on the observer's experience and the extent of biopsy sampling. In general, the histological method has a sensitivity and specificity of 90-95%. In patients treated by proton pump inhibitors, antibiotics or bismuth salts two-four weeks prior to biopsy, the bacteria may be restricted to the corpus or fundus. Culture is strictly indicated in patients after failure of two or more eradication regimens to test for susceptibility and resistence. Specificity is 100% and sensitivity depends on the experience and interest of the microbiologist. The indication of polymerase chain reaction is only for research, specially, in molecular epidemiology and for fingerprinting.

Biopsy↗
PubMedDate not supplied

Selecting and managing a professional consultant to a clinical laboratory.

Managers of clinical laboratories, like those in other complex organizations, will often seek the advice of external professional consultants to provide solutions to current problems. Optimizing the process of selecting and managing consultants to clinical laboratories is the topic of this article. A number of practical tips are offered, including a discussion of the use of nontraditional consultants. Special emphasis is placed on developing a request for proposal and evaluating responses to the request for proposal by the various consulting firms bidding for the engagement. The use of consultants in the health-care arena in general and clinical laboratories in particular will undoubtedly increase as financial and organizational challenges to the industry continue to proliferate.

Competitive Bidding↗
PubMed1999

An integrated dialysis delivery network in Ontario.

In August 1995, the Ontario Ministry of Health (MOH) issued a request for proposal (RFP) for the establishment of new and expanded dialysis services. London Health Sciences Centre (LHSC) was successful in expanding its integrated dialysis delivery network with satellites in Stratford, Woodstock and Owen Sound. This achievement required collaboration of LHSC and host hospital staff to meet the challenging RFP requirements. With final approval received in January 1997, efforts were required to establish an operational model supporting self-care and full-care patients, to train satellite staff and patients, and to manage the resulting clinical impact. A balanced scorecard (Kaplan & Norton, 1992) evaluation model was developed. Initial outcome data indicate that full-care patients in satellites require more fallback support to London units, experience more hypotensive episodes during dialysis and, in some cases, demonstrate lower levels of dialysis adequacy and nutritional status when compared to satellite self-care patients. Findings from these data will assist in revising patient inclusion criteria and processes to optimize community-based dialysis.

Ambulatory Care↗
PubMedDate not supplied

A quality management approach to optimizing delivery and administration of preoperative antibiotics.

OBJECTIVE: To optimize the process for delivering and administering preoperative antibiotics in order to prevent potential adverse patient outcomes. DESIGN: Using a multidisciplinary quality-improvement team, an evaluation of the preoperative medication order and delivery process was conducted. Charts were reviewed by selected time periods, with winter 1994 discharges for orthopedic surgeries (n = 97) and spring 1995 discharges for open heart procedures (n = 50) being used to arrive at baseline data (n = 147). A plan was devised to mainstream the medication-use process so that it would be standardized hospitalwide. A goal of administering preoperative antibiotics within 30 to 60 minutes prior to cut time was established. Following redesign and education, a repeat chart review of orthopedic surgeries (n = 33) and open heart procedures (n = 168) was conducted during April 1997 for discharges from the same diagnosis-related groups to total (n = 201). SETTING: A nearly 1,000-bed tertiary referral center and teaching hospital with three separate campuses. RESULTS: We identified multiple ordering mechanisms, multiple medication sources and delivery sites, multiple administration sites and administering personnel, and other logistical conflicts. Thirty-one percent of cases received antibiotics less than 30 minutes prior to start time, 39% between 30 to 60 minutes, and 30% greater than 60 minutes before start time. Following the multidisciplinary redesign and education, an increase from 39% to 61% receiving preoperative antibiotics between 30 to 60 minutes prior to surgery start time and a decrease from 31% to 18% receiving them in less than 30 minutes was documented. The percentage of patients receiving preoperative antibiotics in 60 minutes or less increased from 70% to 80%. CONCLUSION: A continuous quality-improvement approach that engages all departments involved in patient care is necessary to achieve meaningful change in complicated hospital processes.

Antibiotic Prophylaxis↗
PubMed1999

[Hospital physicians in the light of letters of complaint].

In a competitive health-care system the quality of services and, closely related, customer satisfaction are significant success factors. Some patients or their relatives who are dissatisfied with the provided service express this in letters of complaint. Using the critical incident technique based on a sample of 54 letters of complaint regarding doctors' performance sent to the administration of the Inselspital of Berne we examined information such feedback contains. A total of 133 critical occurrences have been described. Seventy percent of the occurrences were related to medical treatment and 6% to the medical education and research process. The remaining 26% of the complaints concerned accommodation, care, administration or other areas. In the sphere of medical service procedures the dissatisfaction of patients centered on information provided to patients and their families (38%), followed by criticism concerning clinic organization (23%), interaction with the doctor (14%), his professional competence (13%) as well as the management of clinical data (12%). On average, 3 out of 10 letters allude to possible criminal or liability proceedings or seemed to have a potential for escalation in other areas. The situations as presented in these complaints is to be considered as objective and relevant. To continue the process of optimization and quality improvement it is therefore recommendable to take these signals seriously.

Humans↗