Singlet oxygen-mediated synthesis of malarial chemotherapeutic agents

Malaria is the leading infectious disease found in humans, affecting third-world countries. Worldwide, more than two billion people are at risk of malaria, with about 500 million clinical cases of malaria each year and one million deaths. In this focused review, an effort has been made to summarize the reactions of singlet oxygen with organic substrates, their stereoselectivity, stereospecificity and utilization in generating dioxetanes and endoperoxides. The study of production and reactivity indications of this exceptional molecule has emerged as a rich and diverse area in the synthesis of antimalarials like artemisinin and its semisynthetic derivatives, structurally simple 1,2,4-trioxanes, sesquiterpene isonitriles, synthetic cyclic, and other acyclic peroxides. Artermisinin, a mainstay in antimalarial drug therapy, meets the dual challenge posed by drug-resistant parasites and rapid advancement of lethal malarial threat. The cardinal mechanism of peroxidation and ring closure in its production are induced by singlet oxygen and acid. Moreover, its complex structure restricts the complete chemical synthesis of artemisinin. Consequently, the limited availability coupled with increasing demand for artemisinin has paved the way for the preparation of synthetic alternatives of artemisinin and its derivatives. Likewise, past evidence of the structure–activity relationship indicate the importance of singlet oxygen in antimalarial drug synthesis. It is anticipated that this compendium on the chemistry of singlet oxygen will be of use to organic/medicinal chemists and pharmacologists working on antimalarial drug development.     

Contiguous multiple cervicothoracic spinous process fractures in an adult: A case report

Fracture of isolated spinous processes at multiple levels is a rare injury. Herein, we present a 45-year-old male with cervical pain and swelling following a road traffic accident. Computerized tomography and magnetic resonance imaging revealed fractures of spinous process from C7 to D6 vertebra. The patient was managed with rest, analgesics and immobilization. At the 1-year follow-up, the patient is doing well without any neurological problem.     

Brain activation during the voiding phase of micturition in healthy adults: A meta‐analysis of neuroimaging studies

Several studies have used a variety of neuroimaging techniques to measure brain activity during the voiding phase of micturition. However, there is a lack of consensus on which regions of the brain are activated during voiding. The aim of this meta‐analysis is to identify the brain regions that are consistently activated during voiding in healthy adults across different studies. We searched the literature for neuroimaging studies that reported brain co‐ordinates that were activated during voiding. We excluded studies that reported co‐ordinates only for bladder filling, during pelvic floor contraction only, and studies that focused on abnormal bladder states such as the neurogenic bladder. We used the activation‐likelihood estimation (ALE) approach to create a statistical map of the brain and identify the brain co‐ordinates that were activated across different studies. We identified nine studies that reported brain activation during the task of voiding in 91 healthy subjects. Together, these studies reported 117 foci for ALE analysis. Our ALE map yielded six clusters of activation in the pons, cerebellum, insula, anterior cingulate cortex (ACC), thalamus, and the inferior frontal gyrus. Regions of the brain involved in executive control (frontal cortex), interoception (ACC, insula), motor control (cerebellum, thalamus), and brainstem (pons) are involved in micturition. This analysis provides insight into the supraspinal control of voiding in healthy adults and provides a framework to understand dysfunctional voiding. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.