Radioembolization with yttrium-90(90Y) microspheres is an alternative treatment choice for hepatic malignancies and has become incorporated into guidelines by many international oncology and other professional organizations. The tumoricidal effects of radioembolization are predominantly derived from its radioactivity rather than ischemia. Therefore, the overall side effects that have been associated with this therapy, such as fatigue, nausea and vomiting, which are mild but common. Occasionally, severe complications may occur due to incidental embolization of non-target tissue by the microspheres. This review describes in detail the manifestation of side effects and various complications that may be associated with radioembolization using 90Y microspheres. Management and treatment options of these potential adverse events will also be discussed briefly.

Radioembolization with yttrium-90 (90Y) microspheres is a locoregional procedure during which either resin or glass microspheres loaded with β-emitting 90Y are selectively injected into a hepatic artery.The microspheres are trapped in downstream vasculatures,at which point they deliver a cytotoxic dose of radiation to the target tumor.The safety and efficacy of this method have been demonstrated in studies of survival outcomes in patients with nonresectable hepatic malignancies.In this first part of a series of reviews on radioembolization with 90Y microspheres,we cover the basic characteristics of 90Y and 90Y microspheres,techniques for the radioembolization procedure,and methods for ensuring radiation safety and protection.

Yttrium-90 (90Y) radioembolization therapy can directly deliver a high dose of radiation to the tumor being targeted,which has been demonstrated to be effective in treating patients with hepatic malignancy.Compared with transarterial chemoembolization,90Yradioembolization is less frequently associated with toxicities such as abdominal pain,fever,nausea,and vomiting.However,the efficacy and safety of 90Y radioembolization therapy are largely reliant on careful preprocedural evaluation and diligent follow-up.This review discusses the details of essential preprocedural work-up and postprocedural follow-up for patients treated with 90Y radioembolization.

Potential complications arising from yttrium-90 (90Y) radioembolization are often related to inadvertent embolization of non-target vasculature during particle administration.Therefore,careful pretherapeutic planning with arterial mapping is especially important to help identify potential high-risk arteries and vascular communications.A complete pre-therapeutic evaluation of hepatic arterial vasculature includes selective arteriography,precautionary embolization of potential risk arteries and identification of occurrences of hepatopulmonary shunting secondary to tumor-related pathologic arteriovenous channels.The aim of this review is to discuss the pertinent arterial anatomy during 90Y radioembolization therapy and strategies on how to evaluate the risk and prevent the occurrence of non-target embolization through those vascular structures.

Accurate doses of yttrium-90 (90Y) microspheres are critical for the treatment of liver malignancies,because it is closely related to the clinical efficacy and adverse reactions.The dose calculationis primarily based on the type of ~Y delivery medium,whether it is glass microsphere (TheraSpheres) or resin microsphere (SIR-Spheres).The dose calculation of glass microspheres is based on the assumption that the expected radiation dose of the liver and the microspheres can be evenly distributed throughout the liver,while the dose calculation of resin microspheres is based on the assumption that the microspheres are not uniformly distributed throughout the liver,and the degree of this inhomogeneous distribution depends on the extent to which the normal liver is replaced by the tumor tissue.Many other factors may also potentially affect the therapeutic dose of 90Y microspheres.This review will introduce the calculation methods of 90Y microsphere dose,and describe the factors that need to be considered in order to achieve maximum efficacy and avoid adverse effects.

Cyanobacteria are important photosynthetic autotrophic microorganisms and are considered as one of the most promising microbial chassises for photosynthetic cell factories. Glycogen is the most important natural carbon sink of cyanobacteria, playing important roles in regulating its intracellular carbon distributions. In order to optimize the performances of cyanobacterial photosynthetic cell factories and drive more photosynthetic carbon flow toward the synthesis of desired metabolites, many strategies and approaches have been developed to manipulate the glycogen metabolism in cyanobacteria. However, the disturbances on glycogen metabolism usually cause complex effects on the physiology and metabolism of cyanobacterial cells. Moreover, the effects on synthesis efficiencies of different photosynthetic cell factories usually differ. In this manuscript, we summarized the recent progress on engineering cyanobacterial glycogen metabolism, analyzed and compared the physiological and metabolism effects caused by engineering glycogen metabolism in different cyanobacteria species, and prospected the future trends of this strategy on optimizing cyanobacterial photosynthetic cell factories.
Carbon/metabolism* ; Carbon Dioxide/metabolism* ; Cyanobacteria/metabolism* ; Glycogen/metabolism* ; Metabolic Engineering ; Photosynthesis/physiology*