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Objective To prepare desirable quality-control materials for the establishement of qualified external quality assessment on fluorescence in situ hybridization (FISH)-detected prenatal diagnosis of chromosomal aneuploidies. Methods Four types of amniotic fluid cell suspensions (13-trisomy, 18-trisomy, 21-trisomy and 47,XXY) were mixed together by ratio to produce mosaicism with the percentages of each aneuploidy as 10%, 20%, 30% and 40%, respectively. After being stored in liquid nitrogen of −196 °C for six months, randomly selected samples were incubated in 37 °C water, followed by cultivation, hypo-osmosis and fixation. Finally, FISH detetion was applied on them before and after external laboratory mailing, in step with detection on conventional case samples. Results Before mailing, the positive rates of each aneuploidy described above were 12.8%, 23.6%, 33.8%, 44.0%, while 12.6%, 23.8%, 34.0%, 43.5% after mailing. t-test, criteria for stability assessment of quality-control materials in CANS-GL03:2006, showed no significant effect of external mailing on mosaicism since corresponding t values are lower than threshold with significance level α as 0.05 and degree of freedom as 10. Conclusion As FISH detection showed, the mosaic cell strains prepared in current study exhibited excellent stabilities after cryopreservation in −196 °C, subculture, hypo-osmosis, fixation and external laboratory mailing, demonstrating them as reliable and promising quality-control materials for the establishment of a qualified external quality assessment on prenatal diagnosis of chromosomal aneuploidies.

The purpose of our study is to explore the relationship between recovery of neural function and transformation of the internal capsule (IC) after transient middle cerebral artery occlusion (MCAO) by using diffusion kurtosis imaging (DKI).Six male adult Sprague-Dawley rats implemented with transient MCAO were used in this study. Sensorimotor function was assessed according to repetitive behavioral testing on day 1, 3, 7, 14, and 28 after cerebral ischemia. Metrics of DKI were acquired, and the time course of the region-to-normal ratio was evaluated in IC.After cerebral ischemia, relative fractional anisotropy in IC decreased on day 3 (P .01). Relative mean diffusivity (rMD) increased on day 28 (P .05). Relative mean diffusional kurtosis (rMK) increased on day 3 (P .01) and decreased on day 7 (P .05). Relative axial diffusional kurtosis (rKa) increased on day 3 (P .01) and declined on day 7 (P .05). Relative radial diffusional kurtosis (rKr) was reduced on day 7 (P .05). Changes in rMK were larger than changes in rMD on day 3 (P .05). The factor of rKa and rKr revealed marked difference on day 7 (P .05) and day 14 (P .05). Neurological function score showed that rats exhibited functional recovery from day 7 (P .01) post stroke.This longitudinal multiparametric magnetic resonance imaging study suggested that K metrics offers information complimentary to conventional diffusion metrics and revealed the procedure during the structural modification in the ipsilateral IC following focal cerebral ischemia. After transient MCAO, the neural transformation occurred in a time-dependent procedure.

Background Pathomechanism of secondary degeneration in remote regions after ischemic stroke has not been totally clarified. Contrast-enhanced MRI with injecting Gd-DTPA in cisterna magna (CM) is regarded as an efficient method to measure glymphatic system function in brain. Our research aimed at evaluating glymphatic system changes in secondary degeneration areas by contrast-enhanced MRI. Methods Ischemic stroke was induced by left middle cerebral artery occlusion (MCAO) model. A total of 12 Sprague-Dawley rats were randomly divided into three groups: control group with sham operations (n=4), the group of acute phase (1 day after MCAO) (n=4), and the group of subacute phase (7 days after MCAO) (n=4). Contrast-enhanced MRI was performed in 1days or 7days after operations respectively. All rats received an intrathecal injection of Gd-DTPA (2μl/min, totally 20μl) and high-resolution 3D T1-weighted MRI for 6 h. The time course of the signal-to-noise ratio (SNR) in substantia Nigra (SN) and ventral thalamic nucleus (VTN) was evaluated between two hemispheres in all rats. Results In control group without ischemia, time-to-peak of SNR in SN was earlier than that in VTN. There were no differences of SNR between two hemispheres after intrathecal Gd-DTPA administration. In the group of acute phase, MRI revealed similar time course and time-to-peak of SNR between ipsilateral and contralateral VTN, while a tendency of higher SNR in ipsilateral SN than contralateral SN at 4h, 5h, 6h after Gd-DTPA injection. And time-to-peak of SNR was similar in bilateral SN. In the group of subacute phase, time-to-peak of SNR was similar in bilateral VTN, while longer in ipsilateral SN compared with contralateral side. In addition, SNR in T1WI in ipsilateral was significantly higher than SNR in contralateral SN and VTN at 5h (VTN, P= 0.003; SN, P=0.004) and 6h (VTN, P=0.015; SN, P=0.006) after Gd-DTPA injection. Conclusion Glymphatic system was impaired in ipsilateral SN and VTN after ischemic stroke, which may contribute to neural degeneration.

Recent researches document that an oncogenic role of USP22 activation may contribute to progression and predict the prognosis. We have reported that USP22 mediates cell survival and proliferation by promoting the expression of BMI-1 and upregulation of activated AKT pathway in colon cancer cells. However, little is known about its mechanisms in non-small-cell lung cancer (NSCLC). Here the authors investigated the significance of activation of USP22 and potential targets BMI-1, PTEN and phospho-AKT (p-AKT) in NSCLC.Expression levels of USP22, BMI-1, PTEN and p-AKT in samples from 114 patients with NSCLC were evaluated immunohistochemically using the tissue microarray method. Clinical significance was analyzed by multivariate Cox regression analysis, Kaplan-Meier curves and the log-rank test.Immunohistochemically, USP22, BMI-1, p-AKT and PTEN were positive in 66.66%, 78.07%, 71.92% and 43.85% of NSCLC samples, respectively. Statistical correlation analysis showed USP22 to be significantly correlated with BMI-1 (r=0.315, P=0.001), p-AKT (r=0.271, P=0.003), and PTEN (r=-0.384, P0.0001). NSCLCs with positive expression of USP22, BMI-1, p-AKT, and negative expression of PTEN were significantly correlated to tumor size (P=0.0240), differentiation (P=0.0457), pT classification (P=0.0077), pN classification (P=0.0064), and AJCC stage (P=0.0363) and poor overall survival (P0.001). Multivariate Cox proportional hazards model analysis showed that the combined 4 markers was the independent prognostic indicator of overall survival (P0.001; HR, 5.974; 95% CI, 3.307-10.791).The simultaneous targeting of USP22, and its downstream signal transduction molecules seem highly informative in stratification of the cancer into subgroups with distinct likelihood of therapy failure, which contribute to make decision process regarding the individualized therapy selection and optimization.

In rat models to induce both focal cerebral ischemia and chronic cerebral hypoperfusion, it is highly desirable to verify the success of vessel occlusion and reopening with non-invasive method. The contrast-agent free 3D time-of-flight magnetic resonance angiography (TOF-MRA), diffusion-weighted imaging (DWI) and T2-weighted imaging by 3.0-T MR clinical scanner were applied when unilateral middle cerebral artery (MCA) was occluded and reopened, and after bilateral common carotid arteries were in ligation. The arterial angiograms of the rat brain and neck were achieved successfully in all chosen directions by the 3D TOF-MRA. It was shown that MCA in occlusion presented no signal in MRA, and the parenchyma of the ipsilateral MCA territory hypointensity signal in maps of apparent diffusion coefficient (ADC). After reperfusion, the signal intensity of ipsilateral MCA was resumed in MRA, and the decreased ADC was restored simultaneously. However, after 5 h of reperfusion, it was found that the value of ADC deteriorated second time with high T2 value. In bilateral common carotid artery occlusion (BCCAO) rats, it can be confirmed by MRA that the effectively occluded BCCA presented the absent signal and the basilar artery became tortuous. As a result, MRA by clinical scanner was proved of a valuable method to validate transient middle cerebral artery occlusion (MCAO) and permanent BCCAO rat model.