Exosomes are small extracellular vesicles 30-200 nm in diameter that contain many bioactive macromolecules, including proteins, lipids, and nucleic acids; consequently, they play important roles in many physiological and pathological processes and are classified into various property-dependent subtypes. Research into exosome heterogeneity helps broaden our understanding of the physiological and pathological mechanisms associated with exosomes. Exosomes exist in many human biological fluids, with those derived from cerebrospinal fluid (CSF) regarded as potential disease biomarkers. Despite this, few studies have focused on their proteomics, and little research into CSF-derived exosome subtypes has been reported. Traumatic brain injury (TBI) is a major public health issue characterized by a large number of patients and complex pathological processes. While a comprehensive understanding of the pathophysiological processes that underpin TBI is essential for developing therapeutic interventions, proteomic studies into CSF-derived exosomes in patients with TBI are limited. Herein, we designed a tandem size-exclusion chromatography protocol for isolating and profiling the proteins of CSF-derived exosome subtypes from patients with TBI using nanoscale liquid chromatography and trapped-ion mobility spectrometry time-of-flight mass spectrometry (nanoLC-TIMS-TOF-MS). We first centrifuged the collected CSF to remove cells and cell debris, after which it was concentrated by ultrafiltration to increase the exosome concentration and remove small proteins and peptides. A mini-size exclusion chromatography (Mini-SEC) column was then used to separate the exosomes from large amounts of interfering proteins, after which high performance liquid-SEC (HPL-SEC) was used to further separate exosomes according to size. The entire extracellular-vesicle-subset separation and purification process takes approximately 1 h for a single CSF sample. Four differently sized exosome subtypes were successfully isolated and are referred to as S1, S2, S3, and S4 in order of descending size. The S1 subtype exhibited the highest exosome purity according to the particle-to-protein ratio. Multiple characterization methods, including transmission electron microscopy (TEM), Western blotting (WB), and nanoparticle tracking analysis (NTA), confirmed that the exosome subtypes had been successfully acquired. NanoLC-TIMS-TOF-MS, combined with database searching were then used to characterize the proteins. A total of 739 proteins were identified, of which 79% and 72% matched all proteins and the top 100 proteins in the Vesiclepedia database, respectively. Moreover, gene ontology analysis revealed that the identified proteins are mainly located in extracellular exosomes, and that the isolated exosome subtypes are closely related to multiple biological processes, including cell signaling, coagulation, and immune responses. Hierarchical cluster analysis revealed that samples from the same exosome subset are grouped first. Principal-component and Pearson's correlation coefficient analyses revealed that the proteins expressed in the CSF-derived exosome subtypes are heterogeneous. Interestingly, the proteins identified in the S1 subtype varied greatly between samples, highlighting the potential applicability of this subtype to formulating precise therapeutic regimens for different patients. We also analyzed the highly expressed proteins in the exosome subtypes, which revealed that the enrichment pathway of the S1 subtype involves Vitamin B12 metabolism and the regulation of protein catabolic processes, while the specific enrichment pathway of the S2 subtype includes binding and ligand uptake by scavenger receptors, heme scavenging from plasma, and an inflammatory response. In contrast, the unique enrichment pathway of the S3 subtype contains complementary and coagulation cascades and acute-phase responses, while that of the S4 subtype includes post-translational protein phosphorylation. Furthermore, STRING-based protein-association analysis predicted multiple interactions among proteins in the various exosome subtypes. In conclusion, the developed tandem size-exclusion chromatography method was used to isolate cerebrospinal fluid exosome subtypes. This study enriches knowledge regarding cerebrospinal fluid exosomes in patients with TBI based on proteomics.
Objectives: The study aims to investigate the predictive performance of preoperative imaging features combined with tap test for the outcomes of ventriculoperitoneal (VP) shunt in idiopathic normal pressure hydrocephalus (iNPH). Methods: In this multicenter retrospective study, 166 iNPH patients who underwent VP shunt surgery between August 2019 and November 2023 were included. Preoperative clinical characteristics and imaging features were collected. Preoperative clinical assessment and at least 3 months of postoperative follow-up were performed. Multivariable logistic regression, sensitivity, specificity, and the area under the receiver operating characteristic curve (AUC) were used to evaluate predictive performance. Results: Out of 166 total patients, 96 were responders and 70 non-responders. The tap test showed significant difference between two group (p < 0.01). Multivariable logistic regression identified that a positive disproportionately enlarged subarachnoid space (DESH) sign (OR = 0.09, 95% CI: 0.04-0.22, p < 0.001) and a sharper callosal angle (CA) (OR = 0.97, 95% CI: 0.95-1.00, p = 0.02) were associated with symptom improvement after shunt. The sensitivity, specificity, and AUC of tap test were 0.64, 0.60, and 0.62, respectively. Combining CA and the tap test increased sensitivity to 0.85, while combining DESH, CA, and the tap test improved specificity and AUC to 0.67 and 0.72, respectively. Conclusion: The findings suggest that the imaging features DESH and CA, when combined with the tap test, enhance the prediction of VP shunt outcomes in iNPH patients. Despite the improved predictive capability, further research focusing on innovative biomarkers for VP shunt is warranted.
Abstract Background This study aimed to evaluate the T2W hypointense ring and T2-FLAIR mismatch signs in gliomas and use these signs to construct prediction models for glioma grading and isocitrate dehydrogenase (IDH) mutation status. Methods Two independent radiologists retrospectively evaluated 207 glioma patients to assess the presence of T2W hypointense ring and T2-FLAIR mismatch signs. The inter-rater reliability was calculated using the Cohen’s kappa statistic. Two logistic regression models were constructed to differentiate glioma grade and predict IDH genotype noninvasively, respectively. Receiver operating characteristic (ROC) analysis was used to evaluate the developed models. Results Of the 207 patients enrolled (119 males and 88 females, mean age 51.6 ± 14.8 years), 45 cases were low-grade gliomas (LGGs), 162 were high-grade gliomas (HGGs), 55 patients had IDH mutations, and 116 were IDH wild-type. The number of T2W hypointense ring signs was higher in HGGs compared to LGGs (p < 0.001) and higher in the IDH wild-type group than in the IDH mutant group (p < 0.001). There were also significant differences in T2-FLAIR mismatch signs between HGGs and LGGs, as well as between IDH mutant and wild-type groups (p < 0.001). Two predictive models incorporating T2W hypointense ring, absence of T2-FLAIR mismatch, and age were constructed. The area under the ROC curve (AUROC) was 0.940 for predicting HGGs (95% CI = 0.907–0.972) and 0.830 for differentiating IDH wild-type (95% CI = 0.757–0.904). Conclusions The combination of T2W hypointense ring, absence of T2-FLAIR mismatch, and age demonstrate good predictive capability for HGGs and IDH wild-type. These findings suggest that MRI can be used noninvasively to predict glioma grading and IDH mutation status, which may have important implications for patient management and treatment planning.
AIMS:Idiopathic Normal pressure hydrocephalus (iNPH) is a neurodegenerative disease characterized by gait disturbance, dementia, and urinary dysfunction. The neural network mechanisms underlying this phenomenon is currently unknown.METHODS:To investigate the resting-state functional connectivity (rs-FC) abnormalities of iNPH-related brain connectivity from static and dynamic perspectives and the correlation of these abnormalities with clinical symptoms before and 3-month after shunt. We investigated both static and dynamic functional network connectivity (sFNC and dFNC, respectively) in 33 iNPH patients and 23 healthy controls (HCs).RESULTS:The sFNC and dFNC of networks were generally decreased in iNPH patients. The reduction in sFNC within the default mode network (DMN) and between the somatomotor network (SMN) and visual network (VN) were related to symptoms. The temporal properties of dFNC and its temporal variability in state-4 were sensitive to the identification of iNPH and were correlated with symptoms. The temporal variability in the dorsal attention network (DAN) increased, and the average instantaneous FC was altered among networks in iNPH. These features were partially associated with clinical symptoms.CONCLUSION:The dFNC may be a more sensitive biomarker for altered network function in iNPH, providing us with extra information on the mechanisms of iNPH.
This study investigated the relationship between preoperative cerebral blood flow (CBF) in patients with idiopathic normal pressure hydrocephalus (INPH) and preoperative clinical symptoms and changes of clinical symptoms after shunt surgery. A total of 32 patients with diagnosed INPH and 18 age-matched healthy controls (HCs) were involved in this study. All subjects underwent magnetic resonance imaging (MRI), including 3D pulsed arterial-spin labeling (PASL) for non-invasive perfusion imaging, and clinical symptom evaluation at baseline, and all patients with INPH were reexamined with clinical tests 1 month postoperatively. Patients with INPH had significantly lower whole-brain CBF than HCs, with the most significant differences in the high convexity, temporal lobe, precuneus, and thalamus. At baseline, there was a significant correlation between the CBF in the middle frontal gyrus, calcarine, inferior and middle temporal gyrus, thalamus, and posterior cingulate gyrus and poor gait manifestation. After shunting, improvements were negatively correlated with preoperative perfusion in the inferior parietal gyrus, inferior occipital gyrus, and middle temporal gyrus. Preoperative CBF in the middle frontal gyrus was positively correlated with the severity of preoperative cognitive impairment and negatively correlated with the change of postoperative MMSE score. There was a moderate positive correlation between anterior cingulate hypoperfusion and improved postoperative urination. Our study revealed that widely distributed and intercorrelated cortical and subcortical pathways are involved in the development of INPH symptoms, and preoperative CBF may be correlative to short-term shunt outcomes.
The study preliminarily explored the sequence and difference of involvement in different neuroanatomical structures in idiopathic normal pressure hydrocephalus (INPH). We retrospectively analyzed the differences in diffusion tensor imaging (DTI) parameters in 15 ROIs [including the bilateral centrum semiovale (CS), corpus callosum (CC) (body, genu, and splenium), head of the caudate nucleus (CN), internal capsule (IC) (anterior and posterior limb), thalamus (TH), and the bilateral frontal horn white matter hyperintensity (FHWMH)] between 27 INPH patients and 11 healthy controls and the correlation between DTI indices and clinical symptoms, as evaluated by the INPH grading scale (INPHGS), the Mini-Mental State Examination (MMSE), and the timed up and go test (TUG-t), before and 1 month after shunt surgery. Significant differences were observed in DTI parameters from the CS ( p FA1 = 0.004, p ADC1 = 0.005) and the genu ( p FA2 = 0.022; p ADC2 = 0.001) and body ( p FA3 = 0.003; p ADC3 = 0.002) of the CC between the groups. The DTI parameters from the CS were strongly correlated with the MMSE score both pre-operatively and post-operatively. There was association between apparent diffusion coefficient (ADC) values of anterior and posterior limbs of the IC and MMSE. The DTI parameters of the head of the CN were correlated with motion, and the ADC value was significantly associated with the MMSE score. The FA value from TH correlated with an improvement in urination after shunt surgery. We considered that different neuroanatomical structures are affected differently by disease due to their positions in neural pathways and characteristics, which is further reflected in clinical symptoms and the prognosis of shunt surgery.
Citation for published version (APA): Gao, F-J., Wang, D-D., Chen, F., Sun, H-X., Hu, F-Y., Xu, P., Li, J., Liu, W., Qi, Y-H., Li, W., Wang, M., Zhang, S., Xu, G-Z., Chang, Q., & Wu, J-H. (2021). Prevalence and genetic-phenotypic characteristics of patients with USH2A mutations in a large cohort of Chinese patients with inherited retinal disease. British Journal of Ophthalmology, 105(1), 87-92. https://doi.org/10.1136/bjophthalmol-2020-315878
PURPOSE: To evaluate the efficacy and safety of photodynamic therapy (PDT) for macular circumscribed choroidal hemangioma in Chinese patients.DESIGN: Retrospective, consecutive, noncomparative case series.METHODS: Twenty-five eyes (25 patients) with macular circumscribed choroidal hemangioma, 18 subfoveal and 7 perifoveal, with vision impairment attributable to subfoveal fluid and retinal detachment underwent visual acuity testing, fundus fluorescein angiography, ultrasonography, and optical coherence tomography (OCT) examinations to evaluate the efficacy and safety of PDT treatment. PDT was performed with a standard concentration of verteporfin and intravenous injection time. Laser was used at 50 J/cm(2) for 83 seconds on subfoveal and 75 J/cm(2) for 125 seconds on perifoveal lesions. More than 1 spot was used for large lesions and spots overlapped only outside the fovea.RESULTS: The mean follow-up time was 35.5 +/- 15 months. All patients were treated with 1 session except in 2 subfoveal cases. The mean best-corrected visual acuity (BCVA) increased from 0.09 +/- 0.11 to 0.31 +/- 0.37 (P < .01) and 11 patients (44%) had their vision improve over 4 lines. The remaining 14 patients (56%) had stabilized vision with the retina reattached. The mean thickness of the hemangioma before the treatment was 3.2 +/-. 0.9 mm and decreased to 1.3 +/- 1.0 mm post treatment (P < .01), with complete regression of tumor in 7 cases (28%).CONCLUSIONS: PDT with individualized laser parameters for macular circumscribed choroidal hemangioma is effective and safe, leading to improved or stabilized BCVA as a result of tumor shrinkage and the resolution of the subretinal fluid. (Am J Ophthalmol 2010; 150:710-715. (C) 2010 by Elsevier Inc. All rights reserved.)
Pathological myopic macular retinoschisis can be classified into 4 types based on optical coherence tomography (OCT) images: outer layer retinoschisis, outer + middle layer retinoschisis, outer + inner layer retinoschisis and muhilayer retinoschisis. Currently vitrectomy is the major option to treat this condition as it can remove the posterior vitreous cortex completely and peel the internal limiting membrane (ILM) around the posterior vessels arch. Vitrectomy benefits the visual function significantly for outer layer retinoschisis with foveal detachment, but has no or very little effects on muhilayer retinoschisis. The appropriate starting site for removal of posterior cortex and ILM should be the site without inner layer retinoschisis. The knowledge and understanding of the OCT classification of pathological myopic macular retinoschisis is important for us to chose correct operation methods and determine the prognosis after treatment.
In the neural retina, glial cells control the ionic concentrations in part by mediation of transmembrane water fluxes through aquaporin (AQP) water channels. The expression and immunolocalization of two water channels, AQP1 and AQP4, in the rat retina during experimental high salt loading were investigated in this study. Six-week-old Wistar rats were allowed free access to rat chow with 8% NaCl concentration. Of these rats, 6 were killed after 2, 6, 10 and 20 weeks. Twelve-week-old and 26-week-old Wistar rats with a normal diet (0.5% NaCl concentration) were used as controls. Retinal tissues were collected. Ultrathin sections stained with uranyl acetate and lead citrate were photographed using a transmission electron microscope (TEM). Retinal whole mounts and cryosections were immunostained with AQP1 and AQP4 antibodies to detect the immunolocalization changes by confocal microscopy. The AQP1 and AQP4 contents were evaluated by western blot analysis. In control tissues, no intracellular edema and mitochondria swelling were observed by TEM. The immunoreactive AQP4 was expressed by glial cells (Müller cells and astrocytes) predominantly in the inner retina, and AQP1 was expressed in the outer retina. In the retinas of high salt loading animals, obvious intracellular edema was observed by TEM in retinal ganglion cell (RGC) and mitochondria swelling was observed in glial cells. Strong expression of AQP1 was found in glial cells located in the innermost retinal layers, mainly in astrocytes. The superficial retinal vessels were surrounded by AQP4 in control retinas, but by both AQP4 and AQP1 in retina of high salt loading animals. A similar alteration in the localization of AQP1 has been described in the rat retina after transient ischemia and diabetes. Western blot results supported the conclusion that the AQP1 expression increased during high salt diet. Our findings indicate that high salt loading may induce neural retina edema, and that altered glial cell-mediated water transport via AQP channels in the retina may be one of the reasons for intracellular edema in the neural retina.
OBJECTIVE:To investigate the clinical features of Best vitelliform macular dystrophy (BVMD) in Chinese patients.METHODS:Ten consecutive patients (20 eyes) were diagnosed as BVMD by the fundus photography, EOG, fluorescein angiography (FFA) and optical coherence tomography (OCT). Their clinical data were analyzed retrospectively.RESULTS:Of the twenty eyes from ten patients, three eyes from three patients (age range 9-18 years, mean 12.33+/-4.93 years) in Stage II, two eyes from two patients (age range 9-18, mean 13.50+/-6.36 years) in Stage IIa, four eyes from two patients (age range 11-29 years, mean 20.00+/-10.39 years) in Stage III and eleven from six patients (age range 9-44 years, mean 27.09+/-14.02 years) in Stage IV were found at their first presentation to our hospital. OCT scan showed the broadening of the outer-retina-choroid-complex signal with the retinal elevation in Stage II. The moderately reflective material which represents the vitelliform material may accumulate forming a conical mound that would elevate the retinal sensory layer in Stage IIa. In 'pseudohypopon' or atrophy phase there may be a large volume of serous retinal detachment. If a fibrous macular or foveal atrophy was seen in the fundus photograph, the thinning of the outer-retina-choroid-complex signal with serous retinal detachment may be shown by OCT.CONCLUSIONS:The present observation is a first study on the clinical findings of Chinese BVMD patients. It supports the hypothesis that the yellowish material is located under the RPE. Long term evaluation with more patients should be done to acknowledge more characteristics of BVMD in Chinese patients.