Defining susceptibility of broiler chicks to colibacillosis.

This study aimed to define the susceptibility of broilers to colibacillosis through quantification of clinical responses and to examine the relationship between susceptibility and growth retardation. A challenge experiment was carried out twice. In each trial, 192 chicks were challenged intratracheally with Escherichia coli (E. coli) at 7 days of age and 160 chicks served as controls. Surviving chicks were euthanized at 14 or 15 days. Parameters measured were: daily mortality, lesion scores, body weight at 1, 4, 7, 10, 12 and 14 or 15 days and feeding behaviour at 6, 11 and 13 days. The results were reproducible, and increasing susceptibility to colibacillosis was defined by four categories: chicks without lesions, chicks with airsacculitis but no systemic lesions, chicks with systemic lesions, and chicks that die. Increasing susceptibility was associated with increasing growth retardation, but growth retardation was not inevitably linked to challenge with E. coli.     

Accuracy and choice of procedures in 24-hour oesophageal pH monitoring with monocrystalline antimony electrodes

In 24 h pH monitoring, the evaluation is dependent on the absolute accuracy of the pH measurements. Several sources of error exist, such as the chemical composition of calibration buffers and reference electrode gel and the effect of temperature on both the pH and the reference electrodes. We investigated the magnitude of these errors for the monocrystalline antimony electrode. Similar analysis applies to other types of pH electrodes. The errors we found are important when choosing a calibration procedure. We recommend a calibration procedure in which the pH and reference electrodes are both put in a beaker with the calibration buffers prior to and after the 24 h measurements. The calibration buffers and the electrode gel should have a specially selected ion composition where, for example, the Cl-ion concentration is critical. Corrections for differences in temperature between the calibration and the in situ measurements must be added. The pH measurements can be checked by performing in situ calibration.     

DNA fingerprinting of isolates of Staphylococcus aureus from newborns and their contacts

During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, and hospital staff, S. aureus was isolated from 536 of 1,945 specimens. Ninety-three isolates of S. aureus from the three groups of individuals were included in a study to evaluate the potential of DNA fingerprinting for strain differentiation. The 93 isolates were also phage typed and their plasmid profiles were analyzed. Cleavage of DNA with BamHI resulted in 13 different DNA restriction endonuclease band patterns (DNA REBPs), one of which consisted of eight isolates whose DNA was not cleaved with BamHI. The DNAs from these eight isolates were easily cleaved with HindIII. The different DNA REBPs were stable both during in vitro and in vivo growth and allowed strain differentiation within phage groups or types. We could not show any strong association between DNA REBP classes, phage types or groups, and plasmid profiles. Of the 93 isolates, 27 (29.0%) could not be phage typed and 12 (12.9%) lacked plasmids. We therefore conclude that DNA fingerprinting is a powerful tool, in addition to phage typing and plasmid profile analysis, for strain differentiation of S. aureus.     

Genetic homogeneity of Taylorella equigenitalis from Norwegian trotting horses revealed by chromosomal DNA fingerprinting.

Chromosomal DNA fingerprinting indicated that Norwegian Taylorella equigenitalis strains are genetically homogeneous and similar to some Swedish isolates but different from other European strains. As contagious equine metritis is rarely a serious disease in Norwegian horses, we conclude that the dominant T. equigenitalis strain in Norway is a genetically homogeneous clone of low virulence.     

Outline of a typology of men’s use of anabolic androgenic steroids in fitness and strength training environments*

Recent research into the use of anabolic androgenic steroids (AAS) in fitness and strength training environments have revealed great variance in users’ approach to AAS use and more specifically their approach to health risks and desired objectives. However, there have only been few attempts to develop theoretical frameworks directed at conceptualising the variance in AAS use. In this paper, we propose a unified framework in the form of a typology, which concerns men’s general approach to AAS use. The typology is based on sociologist Max Weber’s method on the ideal typology. The work comes out of the authors’ own qualitative empirical research on male AAS users in fitness and strength training environments, but is also related to and draws on the international literature on the subject. The suggested typology consists of four ideal types: the Expert type, the Well-being type, the YOLO type and the Athlete type. The four types are developed around two overarching categories, namely users’ approach to risk and effectiveness. The typology outlines distinct and characteristic approaches to AAS use and can, thus, be employed by researchers as well as health professionals as a heuristic tool for investigation and explanation.     

An outbreak of legionnaires disease caused by long-distance spread from an industrial air scrubber in Sarpsborg, Norway.

BACKGROUND: On 21 May 2005, the Norwegian health authorities were alerted by officials from a local hospital that several recent patients had received the diagnosis of legionnaires disease; all patients resided in 2 neighboring municipalities. We investigated the outbreak to identify the source and to implement control measures. METHODS: We interviewed all surviving case patients and investigated and harvested samples from 23 businesses with cooling towers and other potential infection sources. The locations of the businesses and the patients' residences and movements were mapped. We calculated attack rates and risk ratios among people living within various radii of each potential source. Isolates of Legionella pneumophila were compared using molecular methods. RESULTS: Among 56 case patients, 10 died. The case patients became ill 12-25 May, resided up to 20 km apart, and had not visited places in common. Those living up to 1 km from a particular air scrubber had the highest risk ratio, and only for this source did the risk ratio decrease as the radius widened. Genetically identical L. pneumophila serogroup 1 isolates were recovered from patients and the air scrubber. The air scrubber is an industrial pollution-control device that cleans air for dust particles by spraying with water. The circulating water had a high organic content, pH of 8-9, and temperature of 40 degrees C. The air was expelled at 20 m/s and contained a high amount of aerosolized water. CONCLUSIONS: The high velocity, large drift, and high humidity in the air scrubber may have contributed to the wide spread of Legionella species, probably for >10 km. The risk of Legionella spread from air scrubbers should be assessed.     

Non-random Mating and Convergence Over Time for Mental Health, Life Satisfaction, and Personality: The Nord-Trøndelag Health Study

Earlier studies have shown evidence for various sources of observed spousal similarity regarding different traits and characteristics. We explored the relative contribution of non-random mating and convergence to spouse similarity with respect to global mental health, life satisfaction, optimism, and type A personality. We used population-based data collected for the Nord-Trøndelag Health Study (1984–1986) and prospective registry information about when and with whom people entered into marriage/cohabitation between 1970 and 2000 for 19,599 married/cohabitating couples and 1,551 future couples that entered into marriage/cohabitation during the 16 years after data collection. Couples were categorized by interval between data collection and entry into marriage/cohabitation. Age-adjusted polychoric correlations calculated for each group were used as the dependent variables in non-linear, segmented regression analysis, with time since or until marriage/cohabitation as the independent variable. Initial correlations between partners-to-be were low to moderate, typically around one-half of the values estimated in existing couples, indicating both non-random mating and early convergence. There appeared to be moderate divergence during the first 20 years of marriage/cohabitation and moderate convergence during the rest of life.     

Interviewing Victims of Repeated Domestic Violence: Investigators' Beliefs and Strategies

Most victims of domestic violence are abused repeatedly over time. Hence, investigative challenges arise concerning victims' ability to recall particular events. This research focuses on investigators' understanding of memory-based problems associated with repeated victimization and their strategies to facilitate recall. Eighty-one Swedish police officers completed a questionnaire probing their beliefs about memory for repeated events, aims of witness interviews and specific memory-enhancing techniques. A large proportion reported not making any extra preparations or using specific techniques to tackle the challenges of interviewing victims of repeated violence. However, respondents were largely aware of problematic memory features, including source monitoring errors, and they reported using scientifically supported techniques.