[Camptocormia disclosing Parkinson's disease]

Design and synthesis of five-membered heterocyclic derivatives of istradefylline with comparable pharmacological activity

Parkinson's disease (PD) is a common degenerative disease of the central nervous system among the elderly. Istradefylline, an FDA-approved adenosine A_2A receptor antagonist (anti-PD drug), has good efficacy. However, it has been reported that the double bond of istradefylline is easily converted into cis-configuration when exposed to an indoor environment or direct light in a dilute solution. In order to find more stable adenosine A_2A receptor antagonists with similar pharmacological efficacy to istradefylline, the compounds series I-1 (12 compounds) was designed by maintaining the xanthine skeleton of istradefylline unchanged and replacing the trans-double bond with thiazole or benzothiazole and other biologically active heterocyclic compounds. These compounds were synthesized via multi-step experiment and successfully confirmed through different characterization techniques for their ability to inhibit cAMP formation in A_2A AR overexpressing cells. The thiazole derivative of istradefylline (Compound I-1-11, I-1-12) exhibited significant activity (IC₅₀  = 16.74 ± 4.11 μM, 10.36 ± 3.09 μM), as compared to istradefylline (IC₅₀  = 5.05 ± 1.32 μM). In addition, the molecular docking of benzothiazole derivatives I-1-11 and thiazole derivatives I-1-12 with higher inhibition rate were carried out and compared with istradefylline. The molecular docking results showed that I-1-11 and I-1-12 anchored in the same site as that of XAC (3REY) with predicted affinity binding energy -6.63 kcal/mol and - 6.75 kcal/mol, respectively. Validation through dynamics simulation also showed stable interactions, with fluctuations <3 Å and MM/GBSA energy <-20 kcal/mol. Hence, this study could provide a basis for the rational design of adenosine A_2A receptor antagonists with better potency.

Design Method to Structure Orthosis Design: Camptocormia Postural Brace Case Study

The orthosis is considered a class 1 medical device which often originates from a nonstructured development process. As these devices are mainly developed by small- and medium-sized enterprises, with no standard research method, the result can be an unadapted device which may not respond to the user's needs and which in the short term may be abandoned. One way to solve this problem is to define and apply standard rules and procedures throughout the development/design process. Although methodologies may solve the “empiricism” in orthosis design problems, these design strategies are not applied during orthosis development due to the particularities of this field and the difficulties in linking the required knowledge and the actors that may be present during the orthosis development. The objective of this work is to develop a methodology to structure the orthosis design process that takes into account both the device life cycle and the different stakeholders involved in the design process. A case study was used to validate the proposed methodology. It was applied to the development of an orthosis to treat a specific postural disorder called camptocormia, also known as bent spine syndrome. This disorder is characterized by the anteroflexion of the trunk and especially affects elderly people. Contrary to scoliosis, the characteristics of camptocormia are not permanent, which means that the patient is able to straighten his posture. A postural brace is used to treat this disorder which enables the patient to redress and maintain the correct upright posture of the trunk.

A case of Parkinson's disease following dystonia

Parkinsonism and dystonia are both disorders of the extrapyramidal motor system, and some patients exhibit a complex of the two symptoms. Although several reports have referred to the coexistence of these disorders as parkinsonian disorders with dystonia, in the majority of cases, dystonia appeared after parkinsonism. DAT-scan is useful for the early diagnosis of Parkinson's disease (PD) and other types of parkinsonism such as dementia with Lewy bodies. This case report describes a 67-year old woman diagnosed with axial dystonia without parkinsonism 6 years previously, which had worsened despite treatment with Botulinum toxin injections, and hindered the patient's gait. The patient visited the hospital because of gait disturbances and DAT-scan showed a levodopa transducer decrease in the putamen. A few weeks later, she was re-admitted to hospital and exhibited Parkinsonism. Levodopa improved the gait disturbances but axial dystonia was unchanged, and a clinical diagnosis of PD was made. In the authors' opinion, this was a rare case of parkinsonian disorders with dystonia, characterized by the development of PD after dystonia. DAT-scan may be helpful for the diagnosis of patients with parkinsonian disorders with dystonia.

Painful camptocormia: the relevance of shaking your patient's hand

Camptocormia is an abnormal posture with marked flexion of thoracolumbar spine that abates in the recumbent position. Camptocormia has been described in various neurological (Parkinsonism), muscular (myopathy), psychogenic or orthopedic disorders. There are several hypotheses that can explain this impaired posture but they are usually related to the concomitant pathologies. We report the first case of a patient with confirmed myotonic dystrophy addressed to our medical center for impaired posture who underwent extensive medical exams and explorations because of a myotonic hand. Axial weakness and muscle atrophy, validated by CT-scan imaging, are discussed independent of the concomitant pathology (Parkinson, myopathy).