The growth of microorganisms in total parenteral nutrition admixtures

Total nutrient admixtures (TNAs) containing glucose, amino acids, and lipid emulsion in one container and amino acid/dextrose solutions [conventional total parenteral nutrition (TPN) formulations] were studied in a controlled laboratory experiment for their ability to support the growth of microorganisms. Both TNA and conventional TPN formulations for peripheral and central venous administration with standard additives were inoculated with microorganisms to provide 10(1)-10(2) colony-forming units/ml (CFU/ml) of Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Candida albicans. The admixtures were stored at room temperature and samples for quantitative microbiology were taken at time 0, 6, 12, 24, 48, 72, and 96 hr. K. pneumoniae, E. coli, and P. aeruginosa were able to proliferate in central TNAs, but the growth of these organisms was retarded in conventional TPN solutions. In the peripheral formulations, K. pneumoniae and E. coli proliferated in both the TNA and conventional TPN systems, whereas P. aeruginosa grew well only in the peripheral TNA. S. epidermidis was not able to grow in any admixtures tested; however, C. albicans grew well in all admixtures, but growth was slower in the conventional central TPN. In conclusion, peripheral and central TNAs supported the growth of microorganisms significantly better than conventional TPN solutions.     

Toxic epidermal necrolysis; 15 years'' experience in a Dutch burns centre

BACKGROUND: Toxic epidermal necrolysis (TEN) is a severe and potentially fatal drug reaction characterized by an extensive skin rash with blisters and exfoliation, frequently accompanied by mucositis. The wounds caused by TEN are similar to second-degree burns and severe cases may involve large areas of skin loss. OBJECTIVES: Analysis of our results in patients with TEN and evaluation of the variety of therapeutic interventions that has been studied and suggested in TEN. PATIENTS/METHODS: Retrospective analysis of 19 consecutive patients with TEN treated in our burns centre between 1989 and 2004. RESULTS: Immediate withdrawal of any potentially fatal drug, maximum supportive care, and a restricted and tailored antibiotic, medical and surgical treatment regimen confined mortality to 21%, whereas prognosis scores like APACHE II and SCORTEN predicted mortality of 22 and 30%, respectively. A positive contribution of selective digestive decontamination is suggested but has yet to be established. CONCLUSIONS: Because of a potentially fatal outcome, fast referral of a patient suspected of TEN to a specialized centre (mostly a burns unit or specialized dermatology centre) for expert wound management and tailored comprehensive care is strongly advised and contributes to survival.     

Assessing ethical problem solving by reasoning rather than decision making

Context The assessment of ethical problem solving in medicine has been controversial and challenging. The purposes of this study were: (i) to create a new instrument to measure doctors’ decisions on and reasoning approach towards resolving ethical problems; (ii) to evaluate the scores generated by the new instrument for their reliability and validity, and (iii) to compare doctors’ ethical reasoning abilities between countries and among medical students, residents and experts. Methods This study used 15 clinical vignettes and the think‐aloud method to identify the processes and components involved in ethical problem solving. Subjects included volunteer ethics experts, postgraduate Year 2 residents and pre‐clerkship medical students. The interview data were coded using the instruments of the decision score and Ethical Reasoning Inventory (ERI). The ERI assessed the quality of ethical reasoning for a particular case (Part I) and for an individual globally across all the vignettes (Part II). Results There were 17 Canadian and 32 Taiwanese subjects. Based on the Canadian standard, the decision scores between Taiwanese and Canadian subjects differed significantly, but made no discrimination among the three levels of expertise. Scores on the ERI Parts I and II, which reflect doctors’ reasoning quality, differed between countries and among different levels of expertise in Taiwan, providing evidence of construct validity. In addition, experts had a greater organised knowledge structure and considered more relevant variables in the process of arriving at ethical decisions than did residents or students. The reliability of ERI scores was 0.70–0.99 on Part I and 0.75–0.80 on Part II. Conclusions Expertise in solving ethical problems could not be differentiated by the decisions made, but could be differentiated according to the reasoning used to make those decisions. The difference between Taiwanese and Canadian experts suggests that cultural considerations come into play in the decisions that are made in the course of providing humane care to patients.     

女性慢性下腹痛的干预性治疗

1背景 育龄妇女常见慢性下腹痛，可造成身体损害、情绪忧伤及导致巨大的健康服务费用。美国在这方面的花费超过8亿8千万美元（Mathias 1996）。英国全国数据库的一般性诊治资料显示，慢性下腹痛发病率及流行率与偏头痛、背部痛、哮喘发病率相似（Zondervan 1999）。     

Increased procollagenase activating angiogenic factor in the vitreous humour of oxygen treated kittens.

Previous studies have demonstrated an increase in a low molecular weight angiogenic factor (ESAF) present in the retinae of kittens with oxygen induced retinopathy. The present paper describes differences in the quantity of ESAF extracted from the vitreous humour of control and oxygen treated animals and proposes a mechanism for the induction of intravitreal neovascularisation.     

Identification of two genetic markers that distinguish pathogenic and nonpathogenic strains of Acanthamoeba spp.

Species-level identification of Acanthamoeba isolates is difficult and gives little or no indication of the isolate's pathogenicity. We identified two amplification-based genetic markers that were highly correlated with pathogenicity in Acanthamoeba spp. One marker, designed to amplify a 485-bp fragment of the small-subunit ribosomal RNA gene (ssrDNA), was preferentially amplified from the nonpathogenic strains; amplifications from the pathogenic strains yielded anomalous fragments of 650 and 900?bp. A second marker was developed on the basis of the anomalous 650-bp fragment. Primers to this sequence preferentially amplified a noncoding locus (called Ac6) only from the pathogenic strains. These two genetic markers may be useful for identification of pathogenic Acanthamoeba spp. strains.