校对 ---鹿瓜多肽注射剂质量评价与标准优化

通过探索性研究对鹿瓜多肽注射剂质量现状及存在问题进行评价,并对现行质量标准进行优化。首先,对影响终产品新鲜度的因素进行考察。建立丹磺酰氯柱前衍生-HPLC 法测定鹿瓜多肽注射剂中 8 种生物胺的含量,结果显示个别企业的样品中检出较高浓度的尸胺;采用免疫亲和柱净化-柱后光化学衍生-HPLC -FLD 法测定鹿瓜多肽注射剂及中间提取液中黄曲霉毒素 B₁、B₂、G₁ 和 G₂ 的含量,并采用自动电位滴定法测定甜瓜子原料的酸价和过氧化值,结果表明部分企业生产原料甜瓜子存在霉变、酸败等问题,应在新鲜度方面给予重视。其次,优化了鹿瓜多肽注射剂质量标准中高分子量物质和多肽含量测定的方法。采用 Tricine-SDS-PAGE 电泳法代替凝胶色谱法测定高分子量物质,提高了测定的准确性;采用试剂盒法代替福林酚法测定多肽含量,该法操作简便、专属性更强,适用于大批量样品的快速测定。最后,对鹿瓜多肽注射剂质量标准中缺失的溶血与凝聚、生物学活性测定项目进行研究。建立直接观察法结合酶标仪测定法考察溶血与凝聚反应,结果各企业样品均无溶血与凝聚现象;采用 CCK-8 法考察鹿瓜多肽注射剂对 THP-1 细胞增殖的抑制作用,以此评价其抗炎活性,结果显示鹿瓜多肽注射剂对 THP-1 细胞具有增殖抑制作用,各企业样品的体外抗炎效果具有一定差异。探索性研究结果显示,鹿瓜多肽注射剂原材料、中间产品及终产品的安全性均存在一定隐患,表明本品的整体质量水平一般,且现行质量标准存在缺陷,亟待提高。     

Proposal of a Parameter for OATP1B1 Inhibition Screening at the Early Drug Discovery Stage

It is known that potent inhibition of organic-anion-transporting polypeptide (OATP)1B1 increases exposure to statins, leading to severe adverse effects. The aim of this study was to propose a parameter and its criteria in OATP1B1 inhibition assay at the early drug discovery stage to avoid compounds with the risk of statin-related adverse effects. According to drug label information, most compounds classified as “contraindicated” or “should be avoided” when administered concomitantly with statins increased their AUCs more than 4-fold. Generally, R values where R = 1 + plasma unbound fraction (fu) × maximum inhibitor concentration at the inlet to the liver/IC₅₀ are used to evaluate the extent of clinical drug interaction. However, clinical doses and C_max cannot be determined at the screening stage. Therefore, we estimated the correlations between change in AUC of statins concomitantly administered with OATP1B1 inhibitors and various parameters including fu/IC₅₀. Cyclosporin A, rifampicin, and telaprevir increased the AUC of statins more than 4-fold and fu/IC₅₀ of these compounds was >0.1 L/μmol. On the other hand, fu/IC₅₀ of other compounds was ≤0.03 L/μmol. This study indicates that fu/IC₅₀ is a useful parameter to avoid compounds that seriously affect statin potency through interaction with OATP1B1 at the screening stage.     

甲状腺乳头状癌患者术后首次131I治疗后辐射剂量率的影响因素及出院时间的探讨

目的 探讨甲状腺乳头状癌(PTC)患者术后首次131I治疗后影响辐射剂量率降低的相关因素,并预估其住院隔离时间。方法 选取2015年5月至2018年11月于南方医科大学珠江医院住院并首次行131I治疗的PTC患者167例,其中男性43例、女性124例,年龄(37.14± 12.00)岁。将所有患者按治疗剂量分为高剂量组(63例)和低剂量组(104例),于治疗后24、48、72、96 h时测量距离患者1 m处的辐射剂量率,将治疗后患者体内滞留131I活度为400 MBq时的时间点定为出院时间。采用多重线性回归方法分析影响辐射剂量率降低的相关因素。组间比较采用两独立样本非参数检验或两独立样本t检验。结果 PTC患者首次行131I治疗后的辐射剂量率随时间推移迅速下降,高剂量组治疗后的24、48 h辐射剂量率[(70.62±34.45)、15.64 μSv/h]明显高于低剂量组[(11.27±5.13)、2.03 μSv/h],且差异均有统计学意义(t=-13.581、-7.952,均P <0.01)。81.0%(51/63)和90.5%(57/63)的高剂量组患者分别可在治疗48 h和72 h后出院,99%(103/104)的低剂量组患者可在治疗24 h后出院。多重线性回归分析显示,131I剂量和2 h摄碘率对高剂量组24 h辐射剂量率的影响有统计学意义(F=9.23,复相关系数R2=0.212,P<0.01),高剂量组24 h辐射剂量率与2 h摄碘率和131I剂量呈正相关;性别、24 h摄碘率和残甲法3对高剂量组48 h辐射剂量率的影响有统计学意义(F=34.45,复相关系数R2=0.622,P<0.01),48 h辐射剂量率与24 h摄碘率和残留甲状腺体积呈正相关,与性别呈负相关;131I剂量和24 h饮水量对低剂量组24 h辐射剂量率的影响有统计学意义(F=12.76,复相关系数R2=0.186 ,P<0.01),低剂量组24 h辐射剂量率与131I剂量呈正相关,与24 h饮水量呈负相关。结论 PTC术后患者首次131I治疗24 h后,影响其辐射剂量率降低的主要因素是服用131I的剂量,而48 h后的主要影响因素是24 h甲状腺摄碘率、残留甲状腺体积和性别。低剂量组和高剂量组平均住院时间分别为1 d和2 d左右。     

High grade angiosarcoma fifteen years after breast conservation therapy with radiation therapy: A case report

INTRODUCTION

Angiosarcoma is a rare tumor of the breast. Secondary angiosarcoma of the breast refers specifically to a tumor that arises after a latency period following radiation. With breast conservation therapy gaining significant popularity to that of mastectomy, more cases of secondary angiosarcoma continue to arise in the irradiated fields of these patients.

PRESENTATION OF CASE

The authors describe the case of an 80 year old female who presented fifteen years after her surgery and radiation treatment with two bleeding skin lesions in her breast. These lesions were found to be high grade angiosarcoma upon excision. Due to high cardiac co-morbidity she was treated with re-excision and surveillance.

DISCUSSION

This case is an example of a rare sequela to a common procedure. Breast conservation therapy with lumpectomy and radiation has become a popular technique in treating localized breast cancer. Radiation like all therapy has its known adverse effects. Further work is needed with the small amount of published cases of angiosarcoma after breast irradiation so that we may find optimal treatment plans for these patients. Like any rare entity, difficulty lies in accruing enough cases to compare prognosis and results.

CONCLUSION

Secondary breast angiosarcoma diagnosis requires frequent follow ups and a high index of suspicion. With mastectomy giving the best chance of treatment in these cases, early detection is crucial in this rare sequela.     

Multi-staged flap reconstruction for complex radiation thoracic ulcer

INTRODUCTION

Chest wall reconstruction due to previous radiation therapy can be challenging and complex, requiring a multidisciplinary approach.

PRESENTATION OF CASE

The authors present the case of a 84-year-old woman with a right chest wall radionecrosis ulcer, that was submitted to an ablative surgery resulting in a full-thickness defect of 224 cm², firstly reconstructed with a pedicled omental flap. Due to partial flap necrosis, other debridements and chest wall multi-staged flap reconstruction were performed.

DISCUSSION

This case highlights that the reconstructive choice should be individualized and dependent on patient and local factors. The authors advise that surgical team should work closely and be well versed in chest wall reconstruction with a variety of pedicled flaps, when a complication occurs.

CONCLUSION

A multi-staged flap reconstruction could be a salvage procedure for the coverage of complex, great and complicated chest wall defects due to previous radiation therapy.     

A reduction in chronic hepatitis B virus infection prevalence among children in Vietnam demonstrates the importance of vaccination

Background

Vietnam has high endemic hepatitis B virus infection with >8% of adults estimated to have chronic infection. Hepatitis B vaccine was first introduced in the national childhood immunization program in 1997 in high-risk areas, expanded nationwide in 2002, and included birth dose vaccination in 2003. This survey aimed to assess the impact of Vietnam's vaccination programme by estimating the prevalence of hepatitis B surface antigen (HBsAg) among children born during 2000–2008.

Methods

This nationally representative cross-sectional survey sampled children based on a stratified three-stage cluster design. Demographic and vaccination data were collected along with a whole blood specimen that was collected and interpreted in the field with a point-of-care HBsAg test.

Results

A total of 6,949 children were included in the survey analyses. The overall HBsAg prevalence among surveyed children was 2.70% (95% confidence interval (CI): 2.20–3.30). However, HBsAg prevalence was significantly higher among children born in 2000–2003 (3.64%) compared to children born 2007–2008 (1.64%) (prevalence ratio (PR: 2.22, CI 1.55–3.18)). Among all children included in the survey, unadjusted HBsAg prevalence among children with ≥3 doses of hepatitis B vaccine including a birth dose (1.75%) was significantly lower than among children with ≥3 doses of hepatitis B vaccine but lacked a birth dose (2.98%) (PR: 1.71, CI: 1.00–2.91) and significantly lower than among unvaccinated children (3.47%) (PR: 1.99, CI: 1.15–3.45). Infants receiving hepatitis B vaccine >7 days after birth had significantly higher HBsAg prevalence (3.20%) than those vaccinated 0-1 day after birth (1.52%) (PR: 2.09, CI: 1.27–3.46).

Conclusion

Childhood chronic HBV infection prevalence has been markedly reduced in Vietnam due to vaccination. Further strengthening of timely birth dose vaccination will be important for reducing chronic HBV infection prevalence of under 5 children to <1%, a national and Western Pacific regional hepatitis B control goal.     

Prevalence of chronic hepatitis B virus infection before and after implementation of a hepatitis B vaccination program among children in Nepal

Background

In Nepal, an estimated 2–4% of the population has chronic hepatitis B virus (HBV) infection. To combat this problem, from 2002 to 2004, a national three dose hepatitis B vaccination program was implemented to decrease infection rates among children. The program does not currently include a birth dose to prevent perinatal HBV transmission. In 2012, to assess the impact of the program, we conducted a serosurvey among children born before and after vaccine introduction.

Methods

In 2012, a cross-sectional nationally representative stratified cluster survey was conducted to estimate hepatitis B surface antigen (HBsAg) prevalence among children born from 2006 to 2007 (post-vaccine cohort) and among children born from 2000 to 2002 (pre-vaccine cohort). Demographic data, as well as written and oral vaccination history were collected. All children were tested for HBsAg; mothers of HBsAg positive children were also tested. Furthermore, we evaluated the field sensitivity and specificity of the SD Bioline HBsAg rapid diagnostic test by comparing results with an enzyme immunoassay.

Results

Among 2181 post-vaccination cohort children with vaccination data by either card or recall, 86% (95% confidence interval [CI] 77–95%) received ≥3 hepatitis B vaccine doses. Of 1200 children born in the pre-vaccination cohort, 0.28% (95% CI 0.09–0.85%) were positive for HBsAg; of 2187 children born in the post-vaccination cohort, 0.13% (95% CI 0.04–0.39%) were positive for HBsAg (p = 0.39). Of the six children who tested positive for HBsAg, two had mothers who were positive for HBsAg. Finally, we found the SD Bioline HBsAg rapid diagnostic test to have a sensitivity of 100% and a specificity of 100%.

Conclusions

This is the first nationally representative hepatitis B serosurvey conducted in Nepal. Overall, a low burden of chronic HBV infection was found in children born in both the pre and post-vaccination cohorts. Current vaccination strategies should be continued.     

The delicate balance in genetically engineering live vaccines

Contemporary vaccine development relies less on empirical methods of vaccine construction, and now employs a powerful array of precise engineering strategies to construct immunogenic live vaccines. In this review, we will survey various engineering techniques used to create attenuated vaccines, with an emphasis on recent advances and insights. We will further explore the adaptation of attenuated strains to create multivalent vaccine platforms for immunization against multiple unrelated pathogens. These carrier vaccines are engineered to deliver sufficient levels of protective antigens to appropriate lymphoid inductive sites to elicit both carrier-specific and foreign antigen-specific immunity. Although many of these technologies were originally developed for use in Salmonella vaccines, application of the essential logic of these approaches will be extended to development of other enteric vaccines where possible. A central theme driving our discussion will stress that the ultimate success of an engineered vaccine rests on achieving the proper balance between attenuation and immunogenicity. Achieving this balance will avoid over-activation of inflammatory responses, which results in unacceptable reactogenicity, but will retain sufficient metabolic fitness to enable the live vaccine to reach deep tissue inductive sites and trigger protective immunity. The breadth of examples presented herein will clearly demonstrate that genetic engineering offers the potential for rapidly propelling vaccine development forward into novel applications and therapies which will significantly expand the role of vaccines in public health.