Impaired brain insulin signalling in Parkinson's disease.

AIMS: Brain insulin resistance (i.e., decreased insulin/insulin-like growth factor-1 [IGF-1] signalling) may play a role in the pathophysiology of Parkinson's disease (PD), and several anti-diabetic drugs have entred clinical development to evaluate their potential disease-modifying properties in PD. A measure of insulin resistance is the amount of the downstream messenger insulin receptor substrate-1 that is phosphorylated at serine residues 312 (IRS-1pS312) or 616 (IRS-1pS616). We assessed IRS-1pS312 and IRS-1pS616 expression in post-mortem brain tissue of PD patients and a preclinical rat model based on viral-mediated expression of A53T mutated human α-synuclein (AAV2/9-h-α-synA53T). METHODS: IRS-1pS312 and IRS-1pS616 staining intensity were determined by immunofluorescence in both neurons and glial cells in the substantia nigra pars compacta (SNc) and putamen of PD patients and controls without known brain disease. We further explored a possible relation between α-synuclein aggregates and brain insulin resistance in PD patients. Both insulin resistance markers were also measured in the SNc and striatum of AAV2/9-h-α-synA53T rats. RESULTS: We found higher IRS-1pS312 staining intensity in nigral dopaminergic neurons and a trend for higher IRS-1pS312 staining intensity in putaminal neurons of PD patients. We observed no differences for IRS-1pS616 staining intensity in neurons or IRS-1pS312 staining intensity in glial cells. IRS-1pS312 showed high co-localisation within the core of nigral Lewy bodies. Like PD patients, AAV2/9-h-α-synA53T rats showed higher IRS-1pS312 staining intensity in the SNc and striatum than controls, whereas IRS-1pS616 was not different between groups. CONCLUSIONS: Our results provide evidence for brain insulin resistance in PD and support the rationale for repurposing anti-diabetic drugs for PD treatment.

Reducing reflex first-line prescriptions in a surgical pathology laboratory: toward sustainable practice with positive economic and clinical effects.

In surgical pathology departments, reflex first-line techniques (RFLTs) are aimed at reducing workloads and addressing recent shortages of medical personnel. However, the impacts thereof on economic and diagnostic factors have been poorly addressed. Also, in the era of global warming, environmental considerations are crucial. This study assessed the economic and diagnostic efficacies of routine pathological RFLT and the quality of care and sustainability. Ten RFLTs of the Bordeaux University Hospital pathology department (six special stains, one cytology technique, and three immunohistochemical tests) were studied. First, a retrospective economic analysis evaluated the average cost of these RFLTs per slide and per year. Second, diagnostic relevance was prospectively surveyed. Third, the effects of changes made were analyzed over 2 years. The ten RFLTs were associated with average annual costs of €46,708. Diagnostic relevance analysis indicated that most stains were unnecessary; only 17% were requested as second-line techniques. Elimination of 7/10 tests afforded annual cost savings of €22,522 and reduced the workload by 5568 tests/year, without compromising the workflow or diagnostic quality. Seven of ten RFLTs could be eliminated without compromising diagnostic quality or the workflow. This afforded not only financial benefits but also positive social and environmental impacts. We offer valuable insights into appropriate practices in surgical pathology laboratories. Collaboration between the medical and technical teams was crucial; other healthcare sectors would also benefit from our approach.

Myopathy and scleromyxedema.

Scleromyxedema is a chronic, idiopathic disorder associated with monoclonal gammopathy, and characterized by dermal mucin deposition. However, systemic manifestations are frequent, including neuromuscular symptoms. We herein present a 71-year-old man who developed a vacuolar myopathy in a context of a known scleromyxedema, and we compare our observation with the nineteen other cases found in the medical literature. Such an association (especially with suggestive skin abnormalities) has to be known for two reasons. First, this diagnosis might be quite challenging because the myopathy may precede the typical skin changes. Secondly, conversely to other forms of vacuolar myopathy, some of the symptoms may respond (even partially) to immunomodulatory and/or immunosuppressant therapeutics.