Encapsulation of Cwp84 into pectin beads for oral vaccination against Clostridium difficile

We have designed an oral vaccine against Clostridium difficile infection. The virulent factor Cwp84, that is a cystein protease highly immunogenic in patients with C. difficile-associated disease, was entrapped within pectin beads. Beads encapsulating Cwp84 were shown to be stable in the simulated intestinal medium and to release the cystein protease once in the simulated colonic medium. Three groups of hamsters were immunized, the first receiving pectin beads encapsulating Cwp84, the second unloaded beads and the third one free Cwp84. After three immunizations by the intragastric route, all groups received clindamycine. Post-challenge survival with a strain of C. difficile showed that 2 days after infection, all hamsters treated with unloaded beads and all hamsters treated with free Cwp84 have deceased after 7 days, whereas about 40% of hamsters administered with Cwp84-loaded beads survived 10 days after challenge, proving that oral vaccination provides partial protection. These first data obtained with an oral vaccine against C. difficile appear promising for preventing this infection.     

Herbal Medicines Induced Anticholinergic Poisoning in Hong Kong

In the present review, the main objective was to report the incidence and causes of herbal medicines induced anticholinergic poisoning in Hong Kong during 1989–2012 and to emphasize the importance of pharmacovigilance, investigations and preventive measures. Relevant papers, official figures and unpublished data were obtained from Medline search, the Department of Health and the Drug and Poisons Information Bureau. In the New Territories East (where ~20% of the Hong Kong population lived), the incidence of herbal medicines induced anticholinergic poisoning during 1989–1993 was 0.09 per 100,000 population. There were no confirmed cases during 1994–1996. In the whole of Hong Kong, the incidence during 2000–June 2005 was 0.03 per 100,000 population. Contamination of Rhizoma Atractylodis (50%) and erroneous substitution (42%) were the main causes. The incidence during 2008–2012 was 0.06 per 100,000 population. Contamination of non-toxic herbs (50%) and erroneous substitution (41%) were the main causes. In Hong Kong, contamination of non-toxic herbs by tropane alkaloids and substitution of Flos Campsis by toxic Flos Daturae Metelis were the predominant causes of herbal medicines induced anticholinergic poisoning. Systematic studies along the supply chain are necessary to identify the likely sources of contamination. If erroneous substitution of Flos Campsis by Flos Daturae Metelis could be prevented, 40% of herbal medicines induced anticholinergic poisoning would not have occurred. Regular inspection of the retailer, continuing education for the staff in the herbal trade and repeated publicity measures will also be required. Pharmacovigilance of herbal medicines should help determine the incidence and causes of adverse reactions and monitor the effectiveness of preventive measures.     

Role of retinol in protecting epithelial cell damage induced by Clostridium difficile toxin A

Vitamin A (retinol), a fat-soluble vitamin, is an essential nutrient for the normal functioning of the visual system, epithelial cell integrity and growth, immunity, and reproduction. Our group has investigated the effect of high doses of oral vitamin A on early childhood diarrhea in our prospective community-based studies from Northeast Brazil and found a beneficial role in reducing the mean duration but not incidence of diarrheal episodes. In this study, we explored the role of retinol supplementation in intestinal cell lines following Clostridium difficile toxin A (TxA) challenge. C. difficile is the most common anaerobic pathogen borne with antibiotic-borne diarrhea and pseudomembranous colitis. Since retinol is critical for the integrity of tight junctions and to modulate the cell cycle, we have focused on changes in transepithelial electrical resistance (TEER) in Caco-2, a more differentiated intestinal cell line, and on models of cell proliferation, migration and viability in IEC-6 cells, an undifferentiated crypt cell line, following TxA injury. In this model, retinol therapy reduced apoptosis, improved cell migration and proliferation, and prevented the reduction in TEER, following C. difficile TxA challenge in a glutamine-free medium. These results suggest the role of retinol in protecting intestinal epithelial barrier function from C. difficile TxA enterotoxic damage.     

香港地区药学高等教育的现状及特色

介绍香港地区药学高等教育的发展概况、学制与学位、课程设置、毕业去向、现行的药剂师管理制度等,总结香港药学教育的3个特色。     

The systems for monitoring adverse drug reactions in Hong Kong

Post-marketing surveillance is essential for providing additional safety information on drugs. In Hong Kong, a scheme to monitor ADRs was introduced in October 1986. It relies on voluntary reporting by hospital doctors and general practitioners of suspected ADRs. There appeared to be gross under-reporting as only 68 reports were received between 1986 to 1991. Although hospital-based studies have provided us with information on the pattern of and the risk factors for ADRs, spontaneous reporting on a national scale remains the only feasible and inexpensive method for monitoring ADRs. In order to increase reporting, we hope to convince the medical profession in Hong Kong of the importance in reporting ADRs and to make it easier for them to report.     

Epidemiology and Clinical Features of Ciguatera Fish Poisoning in Hong Kong

In the present review, the main objective was to describe the epidemiology and clinical features of ciguatera fish poisoning in Hong Kong. From 1989 to 2008, the annual incidence of ciguatera varied between 3.3 and 64.9 (median 10.2) per million people. The groupers have replaced the snappers as the most important cause of ciguatera. Pacific-ciguatoxins (CTX) are most commonly present in reef fish samples implicated in ciguatera outbreaks. In affected subjects, the gastrointestinal symptoms often subside within days, whereas the neurological symptoms can persist for weeks or even months. Bradycardia and hypotension, which can be life-threatening, are common. Treatment of ciguatera is primarily supportive and symptomatic. Intravenous mannitol (1 g/kg) has also been suggested. To prevent ciguatera outbreaks, the public should be educated to avoid eating large coral reef fishes, especially the CTX-rich parts. A Code of Practice on Import and Sale of Live Marine Fish for Human Consumption for Prevention and Control of Ciguatera Fish Poisoning was introduced from 2004 to 2013. The Food Safety Ordinance with a tracing mechanism came into full effect in February 2012. The Government would be able to trace the sources of the fishes more effectively and take prompt action when dealing with ciguatera incidents.     

香港中成药注册管理工作概述

目的让更多的人了解香港中成药注册审评的规定与要求,以促进香港中药及中药新药的研究与开发。方法对香港中成药注册的政策法规和香港中成药过渡性注册及非过渡性注册的有关规定进行介绍和分析。结果与结论香港中成药注册管理虽起步较晚,但规范性文件已经制订,其注册管理工作将愈加严格和规范。     

大黄、枳实、厚朴不同炮制品对小承气汤中药效组分的影响

目的研究大黄、枳实、厚朴饮片变化对小承气汤药效组分的影响,以期为临床的合理应用和饮片的质量标准提供参考。方法采用HPLC法分别测定各类成分。大黄游离蒽醌类(芦荟大黄素、大黄酸、大黄素、大黄酚、大黄素甲醚):Syncronis C_(18)色谱柱(250 mm×4.6 mm,5μm);流动相:甲醇–0.1%磷酸;梯度洗脱;体积流量0.8 m L/min;柱温30℃;进样量10μL;检测波长254 nm。大黄结合蒽醌类(番泻苷B、番泻苷A):Syncronis C_(18)色谱柱(250 mm×4.6 mm,5μm);流动相:乙腈–0.05%磷酸;梯度洗脱;柱温30℃;进样量10μL;检测波长340 nm。枳实黄酮苷类(芸香柚皮苷、柚皮苷、橙皮苷、新橙皮苷):Syncronis C_(18)色谱柱(250 mm×4.6 mm,5μm);流动相:乙腈–水;梯度洗脱;体积流量0.7 m L/min;柱温40℃;进样量10μL;检测波长283 nm。厚朴木脂素类成分(和厚朴酚、厚朴酚):Syncronis C_(18)色谱柱(250 mm×4.6mm,5μm);流动相:乙腈–0.05%磷酸;梯度洗脱;体积流量0.7 m L/min;柱温30℃;进样量10μL;检测波长294 nm。结果小承气汤配伍剂量(大黄12 g–炒枳实9 g–姜厚朴6 g)不变,大黄、枳实、厚朴饮片改变时,小承气汤药效组分总量变化规律为:大黄–枳实–姜厚朴酒大黄–炒枳实–姜厚朴熟大黄–炒枳实–姜厚朴大黄炭–炒枳实–姜厚朴≈小承气汤大黄–炒枳实–厚朴,变化率分别为酒大黄组(6.561%)、熟大黄组(4.222%)、大黄炭组(0.118%)、枳实组(30.186%)、厚朴组(-11.218%)。除大黄炭组外,其余组的药效组分总量皆明显变化,其中枳实组变化最明显。结论同一味药材的不同炮制品在小承气汤处方中药效组分不同,对其他药味的影响亦不同,在小承气汤处方配伍中不可随意替代。     

柴胡属饮片中藏柴胡掺伪检测方法研究

目的 以Nepasaikosaponin K为指标,建立柴胡属饮片中藏柴胡掺伪检测方法。方法 采用高效液相色谱-串联质谱技术（HPLC-MS/MS）,电喷雾负离子多反应监测模式,以m/z 943.6→635.5、m/z 943.6→797.4、m/z 943.6→781.5为特征离子对,对北柴胡、南柴胡、锥叶柴胡、竹叶柴胡和藏柴胡等5种常见柴胡属饮片中Nepasaikosaponin K含量进行检测。进一步考察Nepasaikosaponin K定量离子对峰面积与藏柴胡掺伪比例之间线性关系,建立柴胡属饮片中藏柴胡掺伪比例计算公式,并以Nepasaikosaponin K为指标,开展藏柴胡掺伪限度研究。结果 Nepasaikosaponin K在藏柴胡中含量约为其他种柴胡的25~140倍。藏柴胡掺伪比例为0% ~ 100%范围内的混合样品中,定量离子对m/z 943.6→635.5峰面积与掺伪比例之间的线性关系良好。不同柴胡属掺伪模拟样品的计算掺伪量与实际掺伪量偏差在0.6%~1.4%之间。3批市售疑似掺伪北柴胡饮片中藏柴胡掺伪比例分别为14%、16%和27%。结论 该分析方法专属性强,灵敏度高,测定结果准确,为柴胡饮片中藏柴胡的掺伪情况筛查与评价提供依据,同时为其他中药饮片的掺伪情况分析提供新的思路与方法。     

生川乌配伍白蔹、白及反药组合在大鼠血中移行成分的研究

目的鉴定生川乌配伍白蔹、白及的入血成分,比较配伍前后血中移行成分的变化特征。方法大鼠ig给予生川乌配伍白蔹、白及提取物,收集血浆样品并采用UPLC-QTOF/MS法鉴定入血成分,由半定量分析比较配伍前后血中移行成分的变化。结果检测配伍组20个成分,均为来自于生川乌的原形成分,配伍组中双酯型生物碱的相对质量分数均显著降低,单酯型生物碱中苯甲酰乌头原碱的相对质量分数显著降低,醇胺型生物碱中宋果灵的相对质量分数显著降低,其他没有显著性变化。结论生川乌配伍白蔹、白及能够改变其血中移行成分的体内过程。     

Study of an outbreak of ciguatera fish poisoning in Hong Kong.

Ciguatera fish poisoning (CFP) has been a significant and increasing public health problem in Hong Kong since 1980s. With growing demand for imported live coral fishes, the number of people who suffered from this disease has also been increasing. An outbreak of CFP in 2004 was the second most prominent in record as compared with the most significant one that occurred in 1998. In 2004, out of a total of 823 reported food poisoning outbreaks involving 3159 persons, 65 incidents (7.9%) affecting 247 people (7.8%) were attributed to CFP. Validated mouse bioassay analysis of surveillance samples revealed that seven samples (13%) were confirmed to be contaminated with ciguatoxins (CTXs). Typical symptoms of CTXs were found in mice injected with 20mg of fish extracts. The causative fishes included Cheilinus undulatus, Epinephelus coioides, Plectropomus areolatus, and Plectropomus leopardus. Most of these CTX-positive samples analyzed had only trace amounts of CTXs in their extract, except a C. undulatus sample which contained a mice lethal dose (2.5MU/20mg ether extract). This fish species was also the major origin of coral fish that caused clusters of CFP in the last quarter of 2004. Cigua-Check analysis of 20 flesh grains from seven CTX-positive fishes, previously confirmed as CTX-positive samples by mouse bioassay, showed that 50% of flesh grains were CTX contaminated.     

Reporting of adverse drug reactions in relation to general medical admissions to a teaching hospital in Hong Kong

In Hong Kong, adverse drug reactions (ADRs) are rarely reported. We tried to improve the reporting of ADRs in our medical unit at the Prince of Wales Hospital by promoting the scheme at our regular unit meetings and by including report forms at the time of admission in the case notes of all patients admitted to two general medical wards. Registrars and interns based in these wards were requested to report all ADRs by filling in standard report forms. The hospital records of these patients were then reviewed by one investigator with two aims: (1) to assess the proportions of ADRs being reported; (2) to determine how good junior staff are in reporting ADRs. During a 2-month period in 1992, 430 patients were reviewed. A total of 122 ADRs were present in 98 patients either at the time of admission (n = 66) or after admission (n = 56), and of these, only six (5 per cent) were correctly reported. The diagnosis was either missed or wrong in 29 cases, which represent 24 per cent of the total number of ADRs. The remaining 71 per cent of ADRs were totally ignored. Possible ways to improve the reporting of ADRs in hospital are discussed.     

Toxicity and gastric tolerance of essential oils from Cymbopogon citratus, Ocimum gratissimum and Ocimum basilicum in Wistar rats

Oils of Cymbopogon citratus, Ocimum gratissimum and Ocimum basilicum are widely used for their medicinal properties, and as food flavours and perfumes. Recently in a study in West Africa, these oils have been recommended to combat Fusarium verticillioides and subsequent fumonisin contamination in stored maize, but their toxicological profile was not investigated. The current study was undertaken to provide data on acute and subacute toxicity as well as on gastric tolerance of these oils in rat. For this purpose, the oils were given by gavage to Wistar rats for 14 consecutive days. The animals were observed daily for their general behaviour and survival, and their visceral organs such as stomach and liver were taken after sacrifice for histological analyses. A dose-dependent effect of the tested oils was observed during the study. Applied at doses generally higher than 1500 mg/kg body weight, the oils caused significant functional damages to stomach and liver of rat. Unlike the other oils, administration of O. gratissimum oil did not result in adverse effects in rat liver at the tested doses. The no observed adverse effect level (NOAEL) of the tested oils has been established. The three tested oils can be considered as safe to human when applied on stored maize at recommended concentrations.     

The effect of Nepeta cataria extract on adherence and enzyme production of Staphylococcus aureus

Nepeta cataria L., commonly known as catnip, is a perennial herb with a considerable folkloric reputation. A diethyl ether extract of this plant has been shown to have antimicrobial activity against fungi and Gram-positive bacteria. The aim of this work was to study the activity of N. cataria extract on 44 Staphylococcus aureus strains, some resistant to methicillin, and S. aureus 6538P (American Type Culture Collection) by evaluating the effect of subminimum inhibitory concentrations on coagulase, DNAse, thermonuclease and lipase production, and on in-vitro adherence. DNAse, thermonuclease and lipase were inhibited by concentrations equal to 1/2 and 1/4 MIC. A reduction of adherence was also observed.     

In vitro antimicrobial activity of a chitooligosaccharide mixture against Actinobacillus actinomycetemcomitans and Streptococcus mutans

The purpose of this study was to evaluate the in vitro antibacterial activity of a chitooligosaccharide mixture (MW 2000–30 000 Da) with a deacetylation degree of 91.5% against two representative oral pathogens, Actinobacillus actinomycetemcomitans and Streptococcus mutans. A 0.1% concentration of the chitooligosaccharides (derived from the exoskeletons of marine crustaceans) was used to estimate antibacterial activity. Approximately 2 log colony forming units (CFU)/ml of A. actinomycetemcomitans were inactivated by 0.1% chitosan after 30 min, while 120 min exposure inactivated about 4.5 log CFU/ml of this organism. In contrast, the level of inactivation against S. mutans was less than 0.5 log CFU/ml after an exposure of up to 120 min. Electron microscopy showed that the exposure of A. actinomycetemcomitans to the chitooligosaccharides resulted in the disruption of cell membranes and that it could be considered for the treatment of periodontal diseases associated with A. actinomycetemcomitans.     

铜绿假单胞菌合并按蚊伊丽莎白菌肺部感染的病例分析

目的 探讨脑出血患者出现铜绿假单胞菌合并按蚊伊丽莎白菌感染的危险因素及抗菌药物治疗方案。方法 临床药师参与1例脑出血患者铜绿假单胞菌合并按蚊伊丽莎白菌肺部感染的治疗过程,通过查阅文献资料,并结合患者病情、病史、用药史及相关检查结果,分析按蚊伊丽莎白菌致病的危险因素并提出抗菌药治疗方案。结果 临床药师基于感染部位、混合细菌感染特点、抗菌药动学/药效学特性等,在抗感染方案调整为临床医师提出的用药建议后,患者全身感染得到有效控制。 结论 按蚊伊丽莎白菌为条件致病菌,毒力较低,不易感染健康人群。但当患者免疫力低时易转化为致病菌,需引起重视。     

香港采购药品的质量控制与质量保证经验与启示

目的 通过研究香港药品采购的质量控制与质量保证为大陆药品采购提供经验和启示.方法 介绍了香港药品采购的概况,从质量控制、保证的角度对香港药品采购进行分析.结果与结论 香港药品支出仅占拨款的9%~10%,这依赖于香港药品采购中成本管理.而在采购中通过对药品及采购行为的质量控制与质量保证措施,进而保证采购药品的治疗效果.建议大陆药品采购提高采购主体专业能力、充分构建信息化平台、增强事前测试和现场检查力度、采用黑名单制度,引用产品责任保险.