Resistance to conventional anticancer therapies in patients with advanced solid tumors has prompted the need of alternative cancer therapies. Moreover, the success of novel cancer therapies depends on their selectivity for cancer cells with limited toxicity to normal tissues. Several decades after Coley's work a variety of natural and genetically modified non-pathogenic bacterial species are being explored as potential antitumor agents, either to provide direct tumoricidal effects or to deliver tumoricidal molecules. Live, attenuated or genetically modified non-pathogenic bacterial species are capable of multiplying selectively in tumors and inhibiting their growth. Due to their selectivity for tumor tissues, these bacteria and their spores also serve as ideal vectors for delivering therapeutic proteins to tumors. Bacterial toxins too have emerged as promising cancer treatment strategy. The most potential and promising strategy is bacteria based gene-directed enzyme prodrug therapy. Although it has shown successful results in vivo yet further investigation about the targeting mechanisms of the bacteria are required to make it a complete therapeutic approach in cancer treatment.

A cerebrovascular accident, or stroke, is defined as the abrupt onset of a neurological deficit, which can be due to ischemia. Cerebral ischemia is caused by a reduction in blood flow that thereby decreases cerebral metabolism. Chronic cerebral hypoperfusion leads to irreversible brain damage and plays an important role in the development of certain types of dementia. Vinpocetine, chemically known as ethyl apovincaminate, is a vinca alkaloid that exhibits cerebral blood-flow enhancing and neuroprotective effects. Non-clinical and clinical studies have suggested multiple mechanisms responsible for the beneficial neuroprotective effects of vinpocetine. As no significant side effects related to vinpocetine treatment have been reported, it is considered to be safe for long-term use. This vasoactive alkaloid is widely marketed as a supplement for vasodilation and as a nootropic for the improvement of memory. The present review focuses on studies investigating the role of vinpocetine in cerebrovascular diseases.

Artemisinin has been used effectively in malaria treatment. With the emerging resistance to malaria, the optimum and judicial use of the drug has become important. The drug metabolism and toxicology can have an impact on the therapeutic profile and clinical use of this antimalarial agent. In this review, we discuss the pharmacokinetics and toxicological aspects of artemisinin and its therapeutic implications. Artemisinins have several dosing routes including oral, intramuscular, intravenous and rectal. With repeated dosing, artemisinin has propensity for autoinduction, leading to decreased plasma levels on repeated dosing. Combination with other antimalarials in most cases did not influence the pharmacokinetics of artemisinins. Interactions with cytochrome P₄₅₀ inhibitors are known but these neither affect the efficacy nor the toxicity of the respective derivative. Artemisinins are generally regarded to be of low toxicity. Two major problems associated with them are neurotoxicity and reproductive toxicity. But the extent of this neurotoxicity is dependent on the nature of the compound, on the route of administration, and on the nature of the formulation. Moreover, it occurs in humans at very high doses. However, as a matter of precaution, the use of artemisinins in the first trimester of pregnancy has been contraindicated.

To overcome the problems associated with polypharmacy, which include medication non compliance, adverse drug reactions, drug-drug interactions and increased pill-burden, various strategies, such as sustained-release drugs and fixed-dose combination regimens (polypills), have been developed. Out of these, a novel and very much promising approach is the use of dual-action drugs. Amongst the dual-action drugs, there is a class of compounds known as dual inhibitors, which possess the dual inhibitory activity. The most common examples of dual inhibitors are rivastigmine, ladostigil, asenapine, phenserine, amitriptyline, clomipramine, doxepin and desipramine. This review article focuses on the conventional drugs used in different diseases which possess dual inhibition activity as well as those which are still in the preclinical/clinical phase.

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