费氏链霉菌脱氢酶NeoE的生物信息学分析及其对产新霉素的影响

目的 NeoE是费氏链霉菌合成新霉素途径中一种重要的NAD(P)+依赖性脱氢酶,本研究的目的是预测其生物学性质及其对新霉素合成能力的影响。方法 由NCBI网站蛋白质数据库获得NeoE氨基酸序列,利用生物信息学网站及软件分析预测其特征。随后构建neoE过表达质粒,以接合转移方式得到高产重组菌株SF-neoE。最后经摇瓶发酵以及相关基因的转录分析探究NeoE对新霉素生物合成的影响。结果 NeoE由340个氨基酸组成,理论相对分子质量约为35228.33 Da,理论pI值5.14,不存在信号肽和跨膜区,是一个疏水性的稳定胞内蛋白。对含空载质粒菌株和重组菌株摇瓶发酵与RT-qPCR分析,结果表明第48小时neoE的相对表达水平较对照菌株提高了2.1倍,且NeoE的过量表达使得新霉素效价提高42%。结论 该结果为提高新霉素效价提供思路,并为后续定向改造NeoE探究其对费氏链霉菌生长代谢的影响奠定理论基础。     

Kontaktallergien bei Patienten mit Ekzemen des äußeren Gehörgangs Ergebnisse des Informationsverbundes Dermatologischer Kliniken und der Deutschen Kontaktallergie-Gruppe

Zusammenfassung Hintergrund und Fragestellung. Ziel der Untersuchung war die Analyse der innerhalb des Informationsverbundes Dermatologischer Kliniken (IVDK) und der Deutschen Kontaktallergie-Gruppe (DKG) erfassten Daten von Patienten mit Geh?rgangsekzemen. Patienten/Methodik. In dem Datenpool des IVDK wurden zwischen 1992 und 1997 145 Patienten mit Geh?rgangsekzemen gefunden. Ausgewertet wurden neben den DKG-Testreihen auch die getesteten patienteneigenen Substanzen. Ergebnisse. Bei einem Drittel des untersuchten Patientenkollektivs wurde ein allergisches Kontaktekzem diagnostiziert. Inhaltsstoffe medizinischer Externa nahmen eine führende Rolle als Kontaktallergene ein. Im Vergleich der populationskorrigierten Sensibilisierungsh?ufigkeiten (PAFS) zeigte sich für Neomycinsulfat im Untersuchungskollektiv eine deutlich h?here, für Nickelsulfat dagegen eine deutlich niedrigere PAFS als im Gesamtkollektiv. Dies zeigt, dass auf topographisch engstem Raum unterschiedliche Kontaktallergene von Bedeutung sind. Schlussfolgerungen. W?hrend Nickelsulfat am ?u?eren Ohr ein wesentliches Allergen darstellt, dominieren bei Geh?rgangsekzemen die Inhaltsstoffe medizinischer Externa, insbesondere Neomycinsulfat und, wie die Auswertung der getesteten patienteneigenen Substanzen ergab, m?glicherweise auch Polymyxin B.     

Once-daily ofloxacin otic solution versus neomycin sulfate/polymyxin B sulfate/hydrocortisone otic suspension four times a day: a multicenter,randomized, evaluator-blinded trial to compare the efficacy,safety, and pain relief in pediatric patients with otitis externa

ABSTRACT

Introduction: Otitis externa (OE) is an infection of the external auditory canal affecting children and adults and is associated with symptoms of local pain and tenderness. Twice-daily topical treatment with ofloxacin otic solution (0.3% [Floxin otic solution]) for 10 days has been reported to be as effective and well tolerated as neomycin sulfate/polymyxin B sulfate/hydrocortisone otic suspension (Cortisporin otic suspension) administered four times daily for 10 days.

Objective: This study compared the efficacy, safety, and ear-pain resolution of once-daily ofloxacin otic solution (0.3%) versus neomycin sulfate/polymyxin B sulfate/hydrocortisone otic suspension administered four times daily, in children with OE.

Research design, patients, and methods: This multicenter, randomized, parallel-group, evaluator-blinded study was conducted at 34 centers in 278 pediatric OE patients aged 6 months to 12 years. Patients received five drops of ofloxacin otic solution (0.3%) in the affected ears once daily or three drops of neomycin sulfate/polymyxin B sulfate/hydrocortisone otic suspension four times daily, for 7–10 days. Patient evaluations were performed at pretherapy (day 1), end of therapy (days 7–9), and test of cure (7–10 days post-treatment) visits. Data for 208 patients were clinically evaluable and those for 90 patients were microbiologically evaluable. Scores were obtained for patient assessments of pain severity.

Main outcome measures: The overall clinical response was cure in the clinically evaluable patients, demonstrated by resolution of OE signs and symptoms at the test of cure visit. The overall clinical-microbiological response was cure in the microbiologically evaluable patients demonstrated by both clinical cure and microbiological eradication.

Results: For the clinically evaluable patients, equivalent cure rates were obtained between the once-daily ofloxacin-treated and four-times-daily neomycin sulfate/polymyxin B sulfate/hydrocortisone-treated patients (93.8% and 94.7%, respectively). For the clinically and microbiologically evaluable patients, the overall cure rates were 96.4% versus 97.1% for the ofloxacin-treated and neomycin sulfate/polymyxin B sulfate/hydrocortisone-treated patients, respectively. The eradication rates for the prevalent pathogen, Pseudomonas aeruginosa, were 98% versus 100% for ofloxacin-treated and neomycin sulfate/polymyxin B sulfate/hydrocortisone-treated patients, respectively. Decreases in pain severity were similar in both treatment groups. Statistical analyses were limited by the small numbers of patients in each treatment group.

Conclusion: In the treatment of OE in children, once-daily ofloxacin otic solution was as effective and safe as neomycin sulfate/polymyxin B sulfate/hydrocortisone otic suspension given four times daily. The two treatments provide rapid and comparable pain relief; however, ofloxacin otic solution does not have the risk of ototoxicity associated with neomycin and provides effective pain relief without adjunctive steroids.     

Kinetics of killing or growth of Trichomonas vaginalis in the presence of aminoglycosides, neomycin and geneticin (G418)

Few therapeutic drugs, other than metronidazole and close derivatives, are currently available to treat trichomoniasis. Trichomonas vaginalis is known to have a primitive ribosome based on small subunit ribosomal DNA sequence comparisons. Targeting ribosomal subunits, the aminoglycosides neomycin and geneticin (G418, distinct from gentamycin) were tested for activity against T. vaginalis. While neomycin had no effect, G418 was effective in killing cultured T. vaginalis cells at doses intermediate between those previously effective against prokaryotes and eukaryotes. G418 cytotoxicity requires further study before recommending this agent as topically applied therapy in refractory patients.     

新氢化可的松凝胶的制备及质量控制

目的研制新氢化可的松凝胶。方法以硫酸新霉素、氢化可的松为主药制备凝胶,采用抗生素微生物检定法和紫外分光光度法测定凝胶中硫酸新霉素、氢化可的松的含量。结果硫酸新霉素效价为标示量的90%～110%,氢化可的松的平均回收率为100.16%,RSD为0.18%,临床有效率为86.45%。结论该凝胶制备工艺简单,成本低廉,性质稳定,质量可控,疗效确切。     

Suitability of a liquid chromatography assay of neomycin sulfate to replace the microbiological assay for neomycin in USP Monographs

The current USP National Formulary contains 65 Monographs for drug formulations containing neomycin. All 65 Monographs prescribe a bioassay for neomycin assay. This bioassay, based on cell culture, is labor intensive, has poor precision, and cannot be adapted for purity or identification. High-performance anion-exchange chromatography with integrated pulsed amperometric detection (HPAE-IPAD), a liquid chromatography technique, has been shown to be suitable for neomycin purity analysis and neomycin assay of an over-the-counter first aid cream (Hanko and Rohrer [17]). Here we propose that an HPAE-IPAD assay can replace the bioassay in the 65 neomycin-containing Monographs. We applied the HPAE-IPAD assay to four neomycin-containing drug products representing the four classes of formulations found in the 65 Monographs, liquid, solid, suspension, and cream. Each drug was analyzed with two chromatography systems, and on 3 separate days. For all products, HPAE-IPAD measurements were precise and accurate with respect to the label concentrations. There was also high accuracy for spike recovery of neomycin from the four drug products throughout 70–150% of the labeled concentration. These results suggest that an HPAE-IPAD assay would be an accurate assay for neomycin, and would be faster and more precise than the current bioassay.     

Rifaximin,a non-absorbable rifamycin,for the treatment of hepatic encephalopathy. A double-blind,randomised trial

Summary

The aim of this study was to evaluate the efficacy and tolerability of rifaximin, a non-absorbable intestinal antibiotic, in comparison to neomycin in the short- and long-term treatment of hepatic encephalopathy (HE). Forty-nine patients with a definite diagnosis of cirrhosis were included in this double-blind, randomised, controlled trial. Patients were randomly assigned to one of the following treatments: (1) rifaximin 400?mg three times daily: (2) neomycin 1?g three times daily. Both drugs were administrated orally as tablets during 14 consecutive days each month, for a period of six months.

The neuropsychiatric signs and blood ammonia levels were examined before starting the treatment, and every 30 days, until the final assessment.

In all patients a progressive and important reduction in HE grade was observed, and no statistically significant difference between the two treatments was detected.

In both groups the disturbances in speech, memory, behaviour and mood, gait, asterixis, writing, and serial subtraction of 7s and five-pointed star tests all showed the highest proportion of improvement.

During the study blood ammonia levels decreased in both the rifaximin and in the neomycin groups, and again no statistically significant difference was found between groups.

Our findings confirm, therefore, the usefulness of rifaximin in the treatment of HE, supporting its use as a first-choice antibiotic, particularly in patients intolerant to neomycin or with impaired renal function.     

新霉素效价测定方法改进

目的：寻找一种能够长期保存的检定菌以更适于新霉素效价测定。方法：以短小芽孢杆菌代替药典法中的金黄色葡萄球菌测定新霉素效价。结果：在线性范围4．58-21．84μg／ml,两种菌试验结果一致。结论：本试验结果可靠,对药品生产、监督及科研部门更有适用价值。