Current Issue : July-September Volume : 2023 Issue Number : 3 Articles : 5 Articles
Background Extracellular vesicles (EVs), including small EVs (sEVs) such as exosomes, exhibit great potential for the diagnosis and treatment of brain disorders, representing a valuable tool for precision medicine. The latter demands high-quality human biospecimens, especially in complex disorders in which pathological and specimen heterogeneity, as well as diverse individual clinical profile, often complicate the development of precision therapeutic schemes and patient-tailored treatments. Thus, the collection and characterization of physiologically relevant sEVs are of the utmost importance. However, standard brain EV isolation approaches rely on tissue dissociation, which can contaminate EV fractions with intracellular vesicles. Methods Based on multiscale analytical platforms such as cryo-EM, label-free proteomics, advanced flow cytometry, and ExoView analyses, we compared and characterized the EV fraction isolated with this novel method with a classical digestion-based EV isolation procedure. Moreover, EV biogenesis was pharmacologically manipulated with either GW4869 or picrotoxin to assess the validity of the spontaneous-release method, while the injection of labelled-EVs into the mouse brain further supported the integrity of the isolated vesicles. Results We hereby present an efficient purification method that captures a sEV-enriched population spontaneously released by mouse and human brain tissue. In addition, we tested the significance of the release method under conditions where biogenesis/secretion of sEVs was pharmacologically manipulated, as well as under animals’ exposure to chronic stress, a clinically relevant precipitant of brain pathologies, such as depression and Alzheimer’s disease. Our findings show that the released method monitors the drug-evoked inhibition or enhancement of sEVs secretion while chronic stress induces the secretion of brain exosomes accompanied by memory loss and mood deficits suggesting a potential role of sEVs in the brain response to stress and related stress-driven brain pathology. Conclusions Overall, the spontaneous release method of sEV yield may contribute to the characterization and biomarker profile of physiologically relevant brain-derived sEVs in brain function and pathology....
Introduction: Laryngeal cancer is the first cancer of upper aerodigestive tract. Dysphonia, dyspnea and dysphagia are evocative signs. Diagnosis is histological and squamous cell carcinoma is the most common type. The objective of our study was to discuss epidemiological and anatomo-pathological characteristics of laryngeal cancers diagnosed in different pathological anatomy and cytology (ACP) laboratories of Dakar hospitals. Material and method: This was a retrospective study spanning from January 2013 to December 2018 at the pathological anatomy laboratories of Fann, Aristide Le Dantec and Idrissa Pouye hospitals. All patients with laryngeal cancer confirmed at histology were included. Data collection was based on clinical records of the patients and archives of histological reports of the pathological laboratories. Data analysis was performed under the Excel software. Results: We collected 215 cases of laryngeal cancer. The average age was 58.01 years with extremes of 07 and 94 years. The male sex was predominant with 183 patients (85.12%) against 32 women (14.88%). The most noted risk factor was tobacco which affected 14 patients, or 60.87%. Three patients (13.04%) did not present any alcohol-smoking impregnation. Clinically, dysphonia was noted in 22 patients (26.51%). It was associated with dyspnea in 0.48% of cases and dysphagia in 3.61%. Laryngoscopy was performed in 62 patients or 28.83% of cases, nasofibroscopy in 6.45% of cases. Cord arythenoid fixity was noted in two patients (3.23%) and hypo-mobility in 1 patient (1.61%). The most frequent local extension was involvement of the piriform sinus with 11.29% of cases. Palpable lymphadenopathy reported in 17 patients (20.48%). Pathological examination was performed in all patients after post endoscopic biopsy in 92 patients (42.79%), and after obtaining the operative specimen in 123 cases (57.21%). The three floors affected 76 patients (35.35%). The ulcerative budding aspect most noted concerned 108 patients (60.97%). Histologically, it was a squamous cell carcinoma in 205 patients (95.34%). The most site invaded by the tumor was cricoid cartilage.T4 type was most found (45 patients or 40.90%) followed by the T3 type with 34.55%. There was no lymphadenopathy invasion (Type N0) in 74 patients (67.27%), capsular rupture was reported in five patients (6.77%), no evaluable metastasis in 110 patients (97.27%), and stage IVA predominated in 66 patients (60%). Conclusion: laryngeal cancer is a reality in our contexts, however, its incidence is poorly understood in Senegal. The main risk factors remain tobacco and alcohol. Histology confirms the diagnosis. Its management is multidisciplinary and must be early....
The elbow joint is prone to stiffness and adhesion after trauma or surgery. High-energy trauma easily led to loss of mobility of the elbow joint. Mild trauma can also cause stiffness in the elbow joint. In order to investigate the pathogenesis of stiffness and adhesion in elbow joint, a feedback-type elbow joint control system based on network is proposed in this paper. The simulation results show that it has significant differences in elbow bioelectrical impedance in patients with elbow trauma, and this new method realizes the control strategy of converting the patient’s elbow joint pathological information into elbow joint orthosis control information....
Growing evidence suggests a crucial role of neuroinflammation in the pathophysiology of Parkinson’s disease (PD). Neuroinflammation is linked to the accumulation and aggregation of a-synuclein (αSyn), the primary pathological hallmark of PD. Toll-like receptors 4 (TLR4) can have implications in the development and progression of the pathology. In this study, we analyzed the expression of TLR4 in the substantia nigra (SN) and medial temporal gyrus (GTM) of wellcharacterized PD patients and age-matched controls. We also assessed the co-localization of TLR4 with pSer129 αSyn. Using qPCR, we observed an upregulation of TLR4 expression in the SN and GTM in PD patients compared to controls, which was accompanied by a reduction in αSyn expression likely due to the depletion of dopaminergic (DA) cells. Additionally, using immunofluorescence and confocal microscopy, we observed TLR4-positive staining and co-localization with pSer129-αSyn in Lewy bodies of DA neurons in the SN, as well as in pyramidal neurons in the GTM of PD donors. Furthermore, we observed a co-localization of TLR4 and Iba-1 in glial cells of both SN and GTM. Our findings provide evidence for the increased expression of TLR4 in the PD brain and suggest that the interaction between TLR4 and pSer129-αSyn could play a role in mediating the neuroinflammatory response in PD....
Pulmonary damage in SARS-CoV-2 is characterized pathologically by diffuse alveolar damage (DAD) and thrombosis. In addition, nosocomial bacterial superinfections and ventilator-induced lung injury (VILI) are likely to occur. The SARS-CoV-2 Omicron variant have manifested itself as a more diffusive virus which mainly affects the upper airways, such as the nose and pharynx. The mechanism leading to a lung injury with a complex clinical course for the Omicron SARS-CoV-2 variant remains unclear. A key question is whether the organ damage is due to direct organ targeting of the virus or downstream effects such as an altered immune response. An immune escape process of Omicron variant is being studied, which could lead to prolonged viral shedding and increase hospitalization times in patients with comorbidities, with an increased risk of pulmonary co-infections/superinfections and organ damage. This brief commentary reports the current knowledge on the Omicron variant and provides some useful suggestions to the scientific community....
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