Dark Rims: Novel Sequence Enhances Diagnostic Specificity in Multiple Sclerosis

BACKGROUND AND PURPOSE

The 2010 McDonald criteria are designed to sensitively detect MS; however, the low specificity of these criteria can occasionally lead to the misdiagnosis of MS. The purpose of this study was to determine whether a novel double inversion recovery MR imaging technique has the potential to increase the specificity of diagnostic criteria distinguishing MS from non-MS white matter lesions.

MATERIALS AND METHODS

This was a cross-sectional observational study. MR imaging data were acquired between 2011 and 2016. A novel double inversion recovery sequence that suppresses CSF and GM signal was used (GM-double inversion recovery). We compared WM lesions in a group of patients with multiple sclerosis and in a second group of positive controls with white matter lesions who did not have a diagnosis of MS. The presence of a rim on the GM-double inversion recovery MR imaging sequence was combined with the 2001 and 2010 McDonald disseminated-in-space criteria. Multiple MR imaging markers, including lesion location, size, and the presence of a rim, were compared between groups as well as a quantitative measure of lesion T1 hypointensity.

RESULTS

MR images from 107 patients with relapsing-remitting MS (median age, 32 years) and 36 positive control (median age, 39 years) subjects were analyzed. No significant differences were found in age and sex. In patients with MS, 1120/3211 lesions (35%) had a rim on GM-double inversion recovery; the positive control group had only 9/893 rim lesions (1%). Rims were associated with a decrease in the lesion T1 ratio. Using the 2010 MR imaging criteria plus the presence of rims on GM-double inversion recovery, we achieved 78% and 97% specificity in subjects with ≥1 and ≥2 rim lesions, respectively.

CONCLUSIONS

The addition of a novel GM-double inversion recovery technique enhanced specificity for diagnosing MS compared with established MR imaging criteria.

Blockade of miR-663b inhibits cell proliferation and induces apoptosis in osteosarcoma via regulating TP73 expression

OBJECTIVE

This study aimed to investigate the exact role of miR-663b in osteosarcoma (OS) progression and further explore the underlying molecular mechanisms.

MATERIALS AND METHODS

The miR-663b expression in human OS cell lines was determined by qRT-PCR, and the results suggested that miR-663b was highly expressed in human OS cells. TargetScan was used to predict the potential targets of miR-663b, and the prediction was confirmed by dual-luciferase reporter assay. To investigate the role of miR-663b in OS, miR-663b was down-regulated in U2OS cells using miR-663b inhibitor. CCK8 and flow cytometry were preformed to investigate the proliferation and apoptosis of U2OS cells. Moreover, qRT-PCR and western blot analysis were performed to measure the mRNA and protein expression.

RESULTS

We found that miR-663b directly targets TP73 and negatively regulates TP73 expression. MiR-663b inhibitor significantly decreased the proliferation ability of U2OS cells, while the percentage of apoptotic cells was markedly increased. The level of Bcl-2 was notably inhibited by miR-663b inhibitor, while Bax expression was significantly enhanced. Moreover, miR-663b down-regulation promoted p53 and p21 expression in U2OS cells.

CONCLUSIONS

MiR-663b down-regulation represses proliferation and induces apoptosis in OS by targeting TP73. Therefore, we provide a potential therapeutic target for OS treatment (Fig. 6, Ref. 27).

[Application of three questionnaires in screening obstructive sleep apnea in patients with chronic obstructive pulmonary disease]

Objective: To evaluate the clinical value of three questionnaires [Sleep Apnea Clinical Score (SACS), Berlin Questionnaire (BQ), and Epworth Sleepiness Scale (ESS)] in screening obstructive sleep apnea (OSA) in patients with chronic obstructive pulmonary disease (COPD). Methods: A total of 198 patients with COPD were assessed the likelihood of OSA by using the SACS, BQ, ESS, which was confirmed by the overnight polysomnography (PSG). The receiver operating characteristic curve (ROC) and the calculated likelihood ratios were used to compare the values of three scoring systems in predicting OSA in COPD patients. Results: The patients had an average age of (65.5±9.3) years and 92.9% (184 cases) of which were male, 14 cases (7.1%) were female; 27 cases (13.6%) had a high probability of OSA by SACS assessment, 61 cases (30.8%) had a high probability screened by BQ, and 72 (36.4%) had OSA high probability by ESS. The diagnosis of OSA in 75 patients (37.9%) were confirmed by PSG. OSA did not be accurately predicted by ESS screening in patients with COPD, with a ROC curve area under the curve of 0.592 (95% CI: 0.509-0.674, P=0.053). BQ had an area under the ROC curve of 0.706 (95% CI: 0.626-0.779, P<0.001). However, the prediction of SACS was much better, with an area under the ROC curve of 0.810 (95% CI: 0.737-0.871, P<0.001). Conclusion: SACS is superior to BQ and ESS in predicting OSA in this group of patients with COPD.

Serum cystatin C and anti-N-methyl-D-aspartate receptor encephalitis

BACKGROUND

Cystatin C (CysC) is associated with many neurodegenerative disorders and autoimmune diseases, but its relationship with anti-N-Methyl-D-aspartate receptor (anti-NMDAR) encephalitis is unknown.

METHODS

Serum levels of CysC were determined in 66 patients with anti-NMDAR encephalitis and 115 healthy controls. Of the 66 patients, 30 had a follow-up evaluation at 3 months after admission. Association of CysC with anti-NMDAR encephalitis and its clinical parameters were evaluated in the patients.

RESULTS

The serum levels of CysC were significantly lower in patients with anti-NMDAR encephalitis than in controls (0.70 ± 0.13 vs 0.83 ± 0.17 mg/mL, P < .001). Disease severity and disease duration were significantly associated with CysC levels. Furthermore, a follow-up evaluation revealed that after treatment anti-NMDAR encephalitis patients had significantly increased serum CysC levels (P < .001) and significantly decreased modified Rankin Scale (mRS) scores (P < .001) compared with before treatment. In addition, a significant negative correlation was observed between the change in CysC levels and the change in mRS scores (r = -.700, P < .001).

CONCLUSION

Our results show that the serum levels of CysC are associated with anti-NMDAR encephalitis and its clinical parameters and that the changes in CysC levels correlate with therapeutic effect. Therefore, our findings provide new insights into the association between serum CysC and anti-NMDAR encephalitis.

[The therapeutic effect of HSV1-hGM-CSF combined with doxorubicin on the mouse breast cancer model]

Objective: To evaluate the oncolytic effect of herpes simplex virus type 1 which carried recombined human granulocyte-macrophage colony-stimulating factor (HSV1-hGM-CSF) on the mouse breast cancer cell line 4T1 and compare the anticancer effects of HSV1-hGM-CSF, doxorubicin alone or combination on the breast cancer in mice. Methods: We investigated the cytotoxic effect on 4T1 cells in vitro, the cell growth, cell apoptosis and cell cycle of 4T1 cells treated with oncolytic HSV1-hGM-CSF at different MOIs (0, 0.5, 1 and 2) and doxorubicin at different concentrations (0, 2, 4 and 8 μg/ml). The effects of oncolytic HSV1-hGM-CSF and doxorubicin on the tumor growth, survival time and their side effects on the mouse breast cancer model were observed. Results: Both oncolytic HSV1-hGM-CSF and doxorubicin significantly inhibited the proliferation of 4T1 cells in vitro. Doxorubicin induced the G(2)/M phase arrest of 4T1 cells, while the cytotoxicity of oncolytic HSV1-hGM-CSF was no cell cycle-dependent.At day 16 after treatment with doxorubicin and HSV1-hGM-CSF, the tumor volume of 4T1 tumor bearing mice were (144.40±27.68)mm(3,) (216.80±57.18)mm(3,) (246.10±21.90)mm(3,) (327.50±44.24)mm(3,) (213.30±32.31)mm(3) and (495.80±75.87)mm(3) in the groups of doxorubicin combined with high dose HSV1-hGM-CSF, doxorubicin combined with low dose HSV1-hGM-CSF, doxorubicin alone, high dose HSV1-hGM-CSF alone, low dose HSV1-hGM-CSF alone and control, respectively.Compared with the control group, both doxorubicin and HSV1-hGM-CSF treatment exhibited significant reduction of primary tumor volume in vivo (P<0.001). The median survival times were 48, 50, 40, 42, 43 and 37 days in the six groups mentioned above, respectively. The median survival period of doxorubicin alone, high dose HSV1-hGM-CSF alone and low dose HSV1-hGM-CSF alone were significantly longer than that of control (P<0.05). Conclusion: Synergistic effect of sequential treatment with doxorubicin and oncolytic HSV1-hGM-CSF is observed in 4T1 mouse breast cancer.

MicroRNA-645 promotes cell metastasis and proliferation of renal clear cell carcinoma by targeting GK5

OBJECTIVE

To dissect the functioning mode of miR-645 on renal clear cell carcinoma cell metastasis and growth, and provide therapeutic targets for renal clear cell carcinoma.

PATIENTS AND METHODS

Quantitative Real-time PCR (qRT-PCR) assay was employed to detect miR-645 expression level. Wound healing assay and transwell assay were performed to investigate metastasis capacity of renal clear cell carcinoma cells. Cell Counting Kit 8 (CCK8) assay was incorporated to assess cell proliferation capacity. Flow cytometry was used to identify cell apoptosis and cell cycle distribution. Protein levels were assessed by Western blotting assay. The target gene was predicted and verified by bioinformatics analysis and luciferase assay.

RESULTS

MiR-645 was upregulated in renal clear cell carcinoma tissues when compared with para-carcinoma tissues (n=32). Downregulated miR-645 could attenuate cell migration and invasion capacities, as well as inhibited cell proliferation capacity, promoted cell apoptosis and cell cycle arrest at G0/G1 phase. GK5 was chosen as the target gene of miR-645 by bioinformatics analysis and luciferase reporter assay. Moreover, silence of GK5 could rescue tumor suppression role of downregulated miR-645 on renal clear cell carcinoma metastasis.

CONCLUSIONS

Knockdown of miR-645 exerted tumor-suppressive effects on renal clear cell carcinoma metastasis and growth via targeting GK5 in vitro, which provided an innovative and candidate target for diagnose and treatment of renal clear cell carcinoma.

Association of the Glu504Lys polymorphism in the aldehyde dehydrogenase 2 gene with endothelium-dependent dilation disorder in Chinese Han patients with essential hypertension

BACKGROUND

In essential hypertension (EH), 30-50% of the variability in blood pressure is determined by genetic factors. The aldehyde dehydrogenase 2 (ALDH2) gene Glu504Lys polymorphism is associated with 'alcohol flush' and might be associated with EH.

AIMS

The aim of the present study was to investigate the association of the Glu504Lys polymorphism in the ALDH2 gene with endothelium-dependent dilation (EDD) disorder in Chinese Han patients with EH.

METHODS

This case-control study enrolled 1210 patients with EH. The control group consisted of 1089 healthy subjects with normal blood pressure. Patients with EH were divided into normal brachial arterial flow-mediated dilation (FMD) (EH1 group, n = 354) versus endothelial dysfunction (EH2 group, n = 856). ALDH2 gene Glu504Lys polymorphism was detected using a DNA microarray.

RESULTS

The ALDH2 AA/AG genotypes and the A allele frequencies were significantly higher in the EH group compared with healthy controls (both P < 0.05) and significantly higher in the EH2 group compared with the EH1 group (79.8 vs 51.4%; 45.0 vs 29.1%, respectively; both P < 0.05). Multivariate logistic regression analyses showed that the ALDH2 gene Glu504Lys polymorphism was independently associated with EH (dominant: odds ratio (OR) = 1.38; 95% confidence interval (95% CI) = 1.14-2.82; P = 0.01; additive: OR = 1.32; 95% CI = 1.12-2.44; P = 0.02) as well as with EDD in patients with EH (dominant: OR = 1.49, 95% CI = 1.16-3.01, P = 0.02; additive: OR = 1.43, 95% CI = 1.10-2.87, P = 0.03).

CONCLUSION

The ALDH2 Glu504Lys polymorphism was associated with EDD disorders in Chinese Han patients with EH, providing further evidence that this mutation and 'alcohol flush' are not harmless in this Asian population.

Characterization of retroviral infectivity and superinfection resistance during retrovirus-mediated transduction of mammalian cells

Retroviral vectors including lentiviral vectors are commonly used tools to stably express transgenes or RNA molecules in mammalian cells. Their utilities are roughly divided into two categories, stable overexpression of transgenes and RNA molecules, which requires maximal transduction efficiency, or functional selection with retrovirus (RV)-based libraries, which takes advantage of retroviral superinfection resistance. However, the dynamic features of RV-mediated transduction are not well characterized. Here, we engineered two murine stem cell virus-based retroviral vectors expressing dual fluorescence proteins and antibiotic markers, and analyzed virion production efficiency and virion stability, dynamic infectivity and superinfection resistance in different cell types, and strategies to improve transduction efficiency. We found that the highest virion production occurred between 60 and 72 h after transfection. The stability of the collected virion supernatant decreased by >60% after 3 days in storage. We found that RV infectivity varied drastically in the tested human cancer lines, while low transduction efficiency was partially overcome with increased virus titer, prolonged infection duration and/or repeated infections. Furthermore, we demonstrated that RV receptors PIT1 and PIT2 were lowly expressed in the analyzed cells, and that PIT1 and/or PIT2 overexpression significantly improved transduction efficiency in certain cell lines. Thus, our findings provide resourceful information for the optimal conditions of retroviral-mediated gene delivery.

Gradient nonlinearity calibration and correction for a compact, asymmetric magnetic resonance imaging gradient system

Due to engineering limitations, the spatial encoding gradient fields in conventional magnetic resonance imaging cannot be perfectly linear and always contain higher-order, nonlinear components. If ignored during image reconstruction, gradient nonlinearity (GNL) manifests as image geometric distortion. Given an estimate of the GNL field, this distortion can be corrected to a degree proportional to the accuracy of the field estimate. The GNL of a gradient system is typically characterized using a spherical harmonic polynomial model with model coefficients obtained from electromagnetic simulation. Conventional whole-body gradient systems are symmetric in design; typically, only odd-order terms up to the 5th-order are required for GNL modeling. Recently, a high-performance, asymmetric gradient system was developed, which exhibits more complex GNL that requires higher-order terms including both odd- and even-orders for accurate modeling. This work characterizes the GNL of this system using an iterative calibration method and a fiducial phantom used in ADNI (Alzheimer's Disease Neuroimaging Initiative). The phantom was scanned at different locations inside the 26 cm diameter-spherical-volume of this gradient, and the positions of fiducials in the phantom were estimated. An iterative calibration procedure was utilized to identify the model coefficients that minimize the mean-squared-error between the true fiducial positions and the positions estimated from images corrected using these coefficients. To examine the effect of higher-order and even-order terms, this calibration was performed using spherical harmonic polynomial of different orders up to the 10th-order including even- and odd-order terms, or odd-order only. The results showed that the model coefficients of this gradient can be successfully estimated. The residual root-mean-squared-error after correction using up to the 10th-order coefficients was reduced to 0.36 mm, yielding spatial accuracy comparable to conventional whole-body gradients. The even-order terms were necessary for accurate GNL modeling. In addition, the calibrated coefficients improved image geometric accuracy compared with the simulation-based coefficients.

Post-mortem findings in a patient with avian influenza A (H5N6) virus infection

Avian influenza A (H5N6) has been found to infect humans, and has resulted in ten cases with six deaths in China since 2014. Here, we describe the systematic post-mortem pathology of a patient fatally infected with H5N6 virus and evaluate the associated pathogenesis compared with H1N1 pdm09 fatal cases. The most prominent histopathological features were diffuse alveolar damage and pulmonary vasculitis in the lungs of the patient. The virus disseminated to extrapulmonary organs, including the brain. Compared with H1N1 pdm09 fatal infection, H5N6 infection induced a more exacerbated immune response involving overt pulmonary inflammation, which led to alveolar damage and respiratory failure.

Penehyclidine hydrochloride postconditioning ameliorates cerebral ischemia-reperfusion injury: critical role of mitochondrial ATP sensitive potassium channel

Cerebral ischemia/reperfusion (CI/R) leads to disability and death worldwide. However, limited approaches have been made in developing therapies to decrease the detrimental effects of CI/R. In the present study, we evaluated the effects of penehyclidine hydrochloride (PHC) postconditioning on CI/R injury and elucidated the underlying mechanisms. In CI/R rats, we showed that PHC postconditioning could effectively inhibit I/R-induced brain infarction and edema, and deficit of neurological function. In addition, PHC postconditioning significantly inhibited I/R-induced increase of proinflammatory cytokines and TUNEL-positive cell numbers. Moreover, the opening of mitochondrial permeability transition pore (mPTP) and oxidative stress resulting from I/R were suppressed notably by PHC postconditioning, as evidenced by increased absorbance at 540 nm in Ca2+-induced mitochondrial swelling test and increased SOD activity and decreased ROS and MDA level. 5-hydroxydecanoate (5-HD), a specific inhibitor of MitoKATP, was used to evaluate the role of MitoKATP in the neuroprotective effect of PHC postconditioning. The results showed that 5-HD could markedly suppress PHC postconditioning-caused inhibition of brain infarction and edema, deficit of neurological function, inflammation, apoptosis, opening of mPTP and oxidative stress induced by CI/R. The results demonstrated that PHC postconditioning could protect against I/R injury in brain through the inhibition of oxidative stress, mPTP opening, apoptosis and inflammation. Activation of MitoKATP was critical for PHC postconditioning-exhibited neuro-protective effects against I/R injury. These findings may provide a novel foundation for therapeutic strategies targeting cerebral protection against I/R damage.

Regulatory circuit of PKM2/NF-κB/miR-148a/152-modulated tumor angiogenesis and cancer progression

Upregulation of the embryonic M2 isoform of pyruvate kinase (PKM2) emerges as a critical player in the cancer development and metabolism, yet the underlying mechanism of PKM2 overexpression remains to be elucidated. Here we demonstrate that IGF-1/IGF-IR regulates PKM2 expression by enhancing HIF-1α-p65 complex binding to PKM2 promoter. PKM2 expression is regulated by miR-148a/152 suppression. PKM2 directly interacts with NF-κB p65 subunit to promote EGR1 expression for regulating miR-148a/152 feedback circuit in normal cells, but not in cancer cells because of the DNA hypermethylation of miR-148a and miR-152 gene promoters. The silencing of miR-148a/152 contributes to the overexpression of PKM2, NF-κB or/and IGF-IR in some cancer cells. We show that disruption of PKM2/NF-κB/miR-148a/152 feedback loop can regulate cancer cell growth and angiogenesis, and is also associated with triple-negative breast cancer (TNBC) phenotype, which may have clinical implication for providing novel biomarker(s) of TNBC and potential therapeutic target(s) in the future.

Genome-wide association study of myelosuppression in non-small-cell lung cancer patients with platinum-based chemotherapy

Platinum-induced myelosuppression severely impedes successful chemotherapy in non-small-cell lung cancer (NSCLC) patients. Hence, it is clinically important to identify the patients who are at high risk for severe toxicity to certain chemotherapy. We first carried out a genome-wide scan of 906 703 single-nucleotide polymorphisms (SNPs) to identify genetic variants associated with platinum-induced myelosuppression risk in 333 NSCLC patients with chemotherapy. Then, we replicated 24 SNPs that had P<1 × 10(-4) in another independent cohort of 876 NSCLC patients. With P<0.05 as the criterion of statistical significance, we found that rs13014982 at 2q24.3 and rs9909179 at 17p12 exhibited consistently significant associations with myelosuppression risk in both the genome-wide association studies (GWAS) scan and the replication stage (rs13014982: odds ratio (OR)=0.55, 95% confidence intervals (CIs): 0.41-0.74, P=7.29 × 10(-5) for GWAS scan and OR=0.77, 95% CI: 0.65-0.93, P=0.006 for replication stage; rs9909179: OR=0.51, 95% CI: 0.37-0.70, P=4.60 × 10(-5) for GWAS scan and OR=0.82, 95% CI: 0.68-0.99, P=0.040 for replication stage; both in additive model). In combined samples of genome-wide scan and replication samples, the minor alleles of rs13014982 and rs9909179 remained significant associations with the decreased risk of myelosuppression (rs13014982: OR=0.71, 95% CI: 0.61-0.83, P =1.36 × 10(-5); rs9909179: OR=0.76, 95% CI: 0.65-0.89, P=0.001). Rs13014982 at 2q24.3 and rs9909179 at 17p12 might be independent susceptibility markers for platinum-induced myelosuppression risk in NSCLC patients.