Biomarkers of in vivo limbal stem cell function

PurposeTo evaluate in vivo parameters as biomarkers of limbal stem cell function and to establish an objective system that detects and stage limbal stem cell deficiency (LSCD).MethodsA total of 126 patients (172 eyes) with LSCD and 67 normal subjects (99 eyes) were included in this observational cross-sectional comparative study. Slit-lamp biomicroscopy, in vivo laser scanning confocal microscopy (IVCM), and anterior segment optical coherence tomography (AS-OCT) were performed to obtain the following: clinical score, cell morphology score, basal cell density (BCD), central corneal epithelial thickness (CET), limbal epithelial thickness (LET), total corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), and tortuosity coefficient. Their potential correlations with the severity of LSCD were investigated, and cutoff values were determined.ResultsAn increase clinical score correlated with a decrease in central cornea BCD, limbal BCD, CET, mean LET, maximum LET, CNFL, CNFD, CNBD, and tortuosity coefficient. Regression analyses showed that central cornea BCD, CET and CNFL were the best parameters to differentiate LSCD from normal eyes (Coef = 3.123, 3.379, and 2.223; all p < 0.05). The rank correlation analysis showed a similar outcome between the clinical scores and the central cornea BCD (ρ = 0.79), CET (ρ = 0.82), and CNFL (ρ = 0.71). A comprehensive LSCD grading formula based on a combination of these parameters was established.ConclusionsA comprehensive staging system combining clinical presentation, central cornea BCD, CET, and CNFL is established to accurately and objectively diagnose LSCD and stage its severity.     

Comparison of quantitative susceptibility mapping methods on evaluating radiation-induced cerebral microbleeds and basal ganglia at 3T and 7T

Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T₂*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength.     

RIPK3在皮肤基底细胞癌中的表达及意义

目的:研究RIPK3在皮肤基底细胞癌中的表达及意义。方法:应用免疫组化SP法检测皮肤基底细胞癌和正常皮肤组织中RIPK3蛋白的表达情况。用RIPK3特异性siRNA干扰RIPK3在原代表皮角质形成细胞HEKa中的表达，用Annexin V-FITC/PI双染法检测细胞凋亡的变化。结果:在所收集的正常皮肤组织中，RIPK3的阳性表达率为90.0%，而在皮肤基底细胞癌皮损中其表达呈明显下降，阳性率为7.5%，两组RIPK3蛋白的阳性表达率及表达强度的差异均具有统计学意义（P<0.001）。HEKa细胞特异性敲低RIPK3表达后细胞凋亡数量减少。结论:RIPK3在皮肤基底细胞癌中的表达显著低于正常皮肤组织，RIPK3在皮肤基底细胞癌中的异常表达可能是通过抑制细胞程序性死亡而在其发生发展过程中起作用。     

Long‐term therapy of multiple basal cell carcinomas: Clinicodermoscopic score for monitoring of intermittent vismodegib treatment

Vismodegib treatment of multiple basal cell carcinomas (BCCs) is limited by adverse effects and high relapse rates: intermittent regimens are therefore preferred for long‐term administration. The objective of this study was to investigate clinical and dermoscopic changes in BCCs during long‐term intermittent treatment and to identify those most indicative of tumor persistence/clearing. Clinical and dermoscopic images (n = 380 each) of 38 BCCs were acquired at 10 observation times (t0–t9). Biopsies were performed at baseline (t0) and after 72 weeks of treatment (t9). All images were evaluated retrospectively by experts who assessed the presence/absence of 12 clinical and 14 dermoscopic features: clinical scores (CScs) and dermoscopic scores (DScs) were then calculated.     

Efficacy and safety of Vismodegib treatment in patients with advanced basal cell carcinoma and multiple comorbidities

Basal cell carcinoma (BCC) is the most common malignancy in Caucasians, and its incidence is increasing. Most BCCs are treated surgically, nevertheless surgery is not an effective treatment for locally advanced or metastatic BCC. Alterations in hedgehog signaling pathway, a key regulator of cell growth and differentiation during development, are implicated in the pathogenesis of basal‐cell carcinoma. Vismodegib is a small‐molecule inhibitor of smoothened (SMO), a key component of the hedgehog (Hh) signaling pathway, administered in BCC patients, especially when surgery and radiotherapy treatments have failed. We report a series of eight elderly patients treated with vismodegib for advanced BCC and affected by concomitant multiple comorbidities. The efficacy and tolerability of vismodegib in patients with single and/or multiple comorbidities has been poorly studied. In our observation an overall high safety and tolerability has been observed over the course of treatment, with side effects of grade I and II and no changes in vital parameters, electrocardiography and echocardiogram. Vismodegib has been shown to be a safe and well tolerated treatment option for elderly patients affected by multiple comorbidities and advanced BCC.