The impact of a mosquito net voucher subsidy programme on incremental ownership: The case of the Tanzania National Voucher Scheme

The subsidisation of mosquito nets has been widely used to increase ownership in countries where malaria represents a public health problem. However, an important question that has not been addressed empirically is how far net subsidy programmes increase ownership above the level that would have prevailed in the absence of the subsidy (i.e., incremental ownership). This study addresses that gap by investigating the impact of a large‐scale mosquito net voucher subsidy––the Tanzania National Voucher Scheme (TNVS)––on short‐term demand for unsubsidised commercial nets, estimating a household demand model with nationally representative household survey data. The results suggest that, despite the TNVS using a categorical targeting approach that did not discriminate by wealth, it still led to a large increase in incremental ownership of mosquito nets, with limited evidence of displacement of unsubsidised sales. Although no evidence is found of an additional TNVS voucher decreasing the number of unsubsidised sales in the same period, results indicate that an additional TNVS voucher reduced the probability of purchasing any unsubsidised net in the same period by 14%. The findings also highlight the critical role played by social learning or campaign messaging in increasing mosquito net ownership.     

Lapatinib nano-delivery systems: a promising future for breast cancer treatment

Introduction: Breast cancer stands the second prominent cause of death among women. For its efficient treatment, Lapatinib (LAPA) was developed as a selective tyrosine kinase inhibitor of receptors, overexpressed by breast cancer cells. Various explored delivery strategies for LAPA indicated its controlled release with enhanced aqueous solubility, improved bioavailability, decreased plasma protein binding, reduced dose and toxicity to the other organs with maximized clinical efficacy, compared to its marketed tablet formulation.

Areas covered: This comprehensive review deals with the survey, performed through different electronic databases, regarding various challenges and their solutions attained by fabricating delivery systems like nanoparticles, micelle, nanocapsules, nanochannels, and liposomes. It also covers the synthesis of novel LAPA-conjugates for diagnostic purpose.

Expert opinion: Unfortunately, clinical use of LAPA is restricted because of its extensive albumin binding capacity, poor oral bioavailability, and poor aqueous solubility. LAPA is marketed as the oral tablet only. Therefore, it becomes imperative to formulate alternate efficient multiparticulate or nano-delivery systems for administration through non-oral routes, for active/passive targeting, and to scale-up by pharmaceutical scientists followed by their clinical trials by clinical experts. LAPA combinations with capecitabine and letrozole should also be tried for breast cancer treatment.     

功能化纳米粒在脑靶向递药中应用的研究进展

血脑屏障的存在,导致药物不能有效到达靶部位发挥作用,极大的影响神经系统药物的发展和进步。纳米技术已被证明是用于脑靶向治疗的一种有效工具,尤其在脑肿瘤和神经退行性疾病中应用甚广。功能化纳米粒通过表面修饰等提高药物的顺应性,在药物原来的治疗基础上,达到更加精准的靶向性,高效率在靶部位聚集,起到治疗作用。本文主要综述功能化纳米粒及其功能化策略,总结了影响功能化纳米粒脑靶向运输的因素,同时对功能化的纳米粒在脑部疾病治疗中的优势和应用进行阐述,为其相关研究提供参考。     

以Toll样受体为靶点的药物研究进展

Toll样受体是一种保守的模式识别受体,能识别病原相关分子模式(PAMP)和损伤相关分子模式(DAMP),TLRs通过多种信号传递调控免疫系统功能,活化NF-κB信号通路,调节TNF-α、IL-6和IFN-α等多种细胞因子的分泌,从而调节或控制天然免疫与获得性免疫。研究发现,TLRs在自身免疫性疾病、肿瘤等疾病的发生发展过程中起着重要的作用。因此,TLRs正成为重要的药物发现靶点,以TLRs为药物靶点设计的化合物已上市或进入临床研究阶段。本文总结了以TLRs为靶点的药物研究进展。     

包合物脂质体靶向系统在给药中的应用

近年来,包合物和脂质体作为药物的载体被广泛用于药物制剂领域,各自发挥着自身的优势。将环糊精包合物应用于脂质体给药系统——这一新型的药物载体,能够更好地提高靶向给药效果。本文通过概述包合物及脂质体的优势,阐明包合物脂质体这一新型给药系统能提高药物的载药量,增加脂质体的稳定性,对提高药物的吸收和临床疗效等方面具有重要意义,对于靶向给药系统的进一步发展具有新的参考价值。     

Chlorotoxin: A Helpful Natural Scorpion Peptide to Diagnose Glioma and Fight Tumor Invasion

Chlorotoxin is a small 36 amino-acid peptide identified from the venom of the scorpion Leiurus quinquestriatus. Initially, chlorotoxin was used as a pharmacological tool to characterize chloride channels. While studying glioma-specific chloride currents, it was soon discovered that chlorotoxin possesses targeting properties towards cancer cells including glioma, melanoma, small cell lung carcinoma, neuroblastoma and medulloblastoma. The investigation of the mechanism of action of chlorotoxin has been challenging because its cell surface receptor target remains under questioning since two other receptors have been claimed besides chloride channels. Efforts on chlorotoxin-based applications focused on producing analogues helpful for glioma diagnosis, imaging and treatment. These efforts are welcome since gliomas are very aggressive brain cancers, close to impossible to cure with the current therapeutic arsenal. Among all the chlorotoxin-based strategies, the most promising one to enhance patient mean survival time appears to be the use of chlorotoxin as a targeting agent for the delivery of anti-tumor agents. Finally, the discovery of chlorotoxin has led to the screening of other scorpion venoms to identify chlorotoxin-like peptides. So far several new candidates have been identified. Only detailed research and clinical investigations will tell us if they share the same anti-tumor potential as chlorotoxin.     

Targeting prostate cancer: Prostate-specific membrane antigen based diagnosis and therapy

The high incidence rates of prostate cancer (PCa) raise demand for improved therapeutic strategies. Prostate tumors specifically express the prostate-specific membrane antigen (PSMA), a membrane-bound protease. As PSMA is highly overexpressed on malignant prostate tumor cells and as its expression rate correlates with the aggressiveness of the disease, this tumor-associated biomarker provides the possibility to develop new strategies for diagnostics and therapy of PCa. Major advances have been made in PSMA targeting, ranging from immunotherapeutic approaches to therapeutic small molecules. This review elaborates the diversity of PSMA targeting agents while focusing on the radioactively labeled tracers for diagnosis and endoradiotherapy. A variety of radionuclides have been shown to either enable precise diagnosis or efficiently treat the tumor with minimal effects to nontargeted organs. Most small molecules with affinity for PSMA are based on either a phosphonate or a urea-based binding motif. Based on these pharmacophores, major effort has been made to identify modifications to achieve ideal pharmacokinetics while retaining the specific targeting of the PSMA binding pocket. Several tracers have now shown excellent clinical usability in particular for molecular imaging and therapy as proven by the efficiency of theranostic approaches in current studies. The archetypal expression profile of PSMA may be exploited for the treatment with alpha emitters to break radioresistance and thus to bring the power of systemic therapy to higher levels.