加替沙星无菌检查方法的建立与标准操作探讨

目的:建立加替沙星原料及制剂无菌检查法及标准操作方法。方法:按2005年版中国药典无菌检查法验证实验的有关要求,通过接种阳性代表菌株,对薄膜过滤、添加中和剂等去除加替沙星抗菌活性的实验方法和条件进行验证,逐步建立加替沙星原料及制剂无菌检查的标准操作方法。结果:在对加替沙星不同原料及制剂样品适当的处理基础上,采用薄膜过滤法,以0.1%蛋白胨水溶液作为冲洗液,约每滤筒300 mL 的冲洗量,每筒培养基中加入0.1 mol·L~(-1)硫酸锰溶液3 mL 可去除加替沙星对细菌的抑菌作用。结论:加替沙星具有较强的抑菌活性,通过适当的样品处理、薄膜过滤法和添加硫酸锰溶液作为重金属络合剂,去除加替沙星抑菌活性,可对解决喹诺酮类抗生素无菌检查问题起到较好的参考作用。     

An empirical evaluation of the performance of antibody identification tasks

Four empirical studies were conducted for better understanding of the nature of problem-solving activities by medical technologists and medical technology students when performing antibody identification tasks. The results indicated the importance of strategies that ensure the collection of converging evidence, as these strategies protect against the fallibility of commonly used heuristics and against errors due to simple slips. The results also indicate that not only do students make significant numbers of errors, but so do practicing technologists. In one of the studies covering a 1-year period, for instance, a group of 16 technologists made a total of 41 errors in 1057 cases. On the basis of these findings, several alternatives are proposed to reduce errors.     

How safe is diathermy in patients with cochlear implants?

INTRODUCTION

Cochlear implants are surgically inserted electrical devices that enable severely or profoundly deaf individuals to interpret sounds from their environment and communicate more effectively. As a result of their electrical nature, they are susceptible to electromagnetic interference and can be damaged by excessive electrical energy. Surgical diathermy is one source of such potentially damaging energy. The British Cochlear Implant Group guidelines advise that monopolar diathermy should not be used in the head and neck region in patients with cochlear implants and that bipolar diathermy should not be used within 2cm of the implant (http://www.bcig.org.uk/site/public/current/safety.htm).

METHODS

A questionnaire was provided to 36 surgeons working in different specialties in the head and neck region, inquiring as to their knowledge of the safety considerations when using diathermy in cochlear implant patients. Thirty-five surgeons provided responses.

RESULTS

Overall, 77% of the respondents were unaware of the existence of published guidelines. Even when given an option to seek advice, 11% erroneously felt it was safe to use monopolar diathermy above the clavicles with a cochlear implant in situ and 49% felt that there was no restriction on the use of bipolar diathermy.

CONCLUSIONS

There is a significant deficit in the knowledge of safe operating practice in the rapidly expanding population of patients with cochlear implants which threatens patient safety. Through this publication we aim to increase awareness of these guidelines among members of the surgical community and this paper is intended to act as a point of reference to link through to the published safety guidelines.     

Erythropoietin structure-function relationships: high degree of sequence homology among mammals

To investigate structure-function relationships of erythropoietin (Epo), we have obtained cDNA sequences that encode the mature Epo protein of a variety of mammals. A first set of primers, corresponding to conserved nucleotide sequences between mouse and human DNAs, allowed us to amplify by polymerase chain reaction (PCR) intron 1/exon 2 fragments from genomic DNA of the hamster, cat, lion, dog, horse, sheep, dolphin, and pig. Sequencing of these fragments permitted the design of a second generation of species-specific primers. RNA was prepared from anemic kidneys and reverse-transcribed. Using our battery of species-specific 5' primers, we were able to successfully PCR- amplify Epo cDNA from Rhesus monkey, rat, sheep, dog, cat, and pig. Deduced amino acid sequences of mature Epo proteins from these animals, in combination with known sequences for human, Cynomolgus monkey, and mouse, showed a high degree of homology, which explains the biologic and immunological cross-reactivity that has been observed in a number of species. Human Epo is 91% identical to monkey Epo, 85% to cat and dog Epo, and 80% to 82% to pig, sheep, mouse, and rat Epos. There was full conservation of (1) the disulfide bridge linking the NH2 and COOH termini; (2) N-glycosylation sites; and (3) predicted amphipathic alpha- helices. In contrast, the short disulfide bridge (C29/C33 in humans) is not invariant. Cys33 was replaced by a Pro in rodents. Most of the amino acid replacements were conservative. The C-terminal part of the loop between the C and D helices showed the most variation, with several amino acid substitutions, deletions, and/or insertions. Calculations of maximum parsimony for intron 1/exon 2 sequences as well as coding sequences enabled the construction of cladograms that are in good agreement with known phylogenetic relationships.