External Quality Assessment for Rubella Virus RNA Detection Using Armored RNA in China.

BACKGROUND: Although tremendous efforts have been made to reduce rubella incidence, there are still 300 new cases of congenital rubella syndrome daily; thus, rubella infections remain one of the leading causes of preventable congenital birth defects. An effective surveillance system, which could be achieved and maintained by using an external quality assessment program, is critical for prevention and control of this disease. METHODS: Armored RNAs, which are noninfectious and RNase-resistant, were used for encapsulation of the E1 gene of rubella virus and for preparation of a 10-specimen panel for external quality assessment. Thirty-two laboratories across mainland China that used nucleic acid tests for rubella virus RNA detection were included in the external quality assessment program organized by the National Center for Clinical Laboratories of China. RESULTS: Different kinds of commercial kits were used by the laboratories for nucleic acid extraction and TaqMan real-time reverse-transcription PCR for rubella virus RNA detection; 99.2% sensitivity and 100% specificity were achieved in this external quality assessment program. CONCLUSIONS: Most of the participating laboratories obtained accurate results for rubella nucleic acid tests, thereby achieving the quality required for regional rubella and congenital rubella syndrome elimination.

Potential of diffusion tensor MRI in the assessment of periventricular leukomalacia.

AIM: To investigate magnetic resonance (MR) diffusion tensor imaging (DTI) and fibre tractography in the assessment of altered major white matter (WM) fibre tracts in periventricular leukomalacia (PVL). MATERIALS AND METHODS: Twelve children (male:female = 7:5, age range 3-10 years; mean age = 6.5 years) who had suffered PVL were included in this study. Meanwhile, Twelve age-matched normal controls (male:female = 6:6, age range 4-12 years; mean age = 7.3 years) with normal MRI findings and no neurological abnormalities were recruited for comparison. DTI was performed with 15 different diffusion gradient directions and DTI colour maps were created from fractional anisotropy (FA) values and the three vector elements. To identify alteration of WM fibre tracts in patient of PVL quantitatively, FA values on diffusion tensor colour maps were compared between the patients and controls. Quantitative analysis was performed using the regions of interest (ROI) method settled on the central part of all identifiable WM fibres, including the corticospinal tract (CST) in the brainstem, middle cerebellar peduncle (MCP), medial lemniscus (ML), anterior/posterior limb of internal capsule (ICAL/ICPL), arcuate fasciculus (AF), posterior thalamic radiation (PTR), genu of corpus callosum (GCC), splenium of corpus callosum (SCC), corona radiata (CR), cingulum (CG), and superior longitudinal fasciculus (SLF). The averaged FA value of each WM fibre was measured and summarized as the mean +/- standard deviation (SD). All data were analysed by paired Student's t-test. A p-value of less than 0.05 was considered to indicate statistical significance. RESULTS: Visual investigation of WM fibre tracts showed that the ICAL, brainstem CST, ML, MCP, and external capsule (EC) was similar in controls and subjects. However, the ICPL, AF, PTR, CR, CG, SLF and corpus callosum, were all attenuated in size. All 12 cases of PVL showed a significant mean FA reduction in the ICPL, AF, PTR, CR, CG, SLF, SCC, and GCC in comparison with the ipsilateral regions of healthy controls (p<0.05). However, there were no statistically significant differences of the ICAL, ML, MCP, and brainstem CST when analysed using a two-tailed Student's t-test for paired data (p>0.01). CONCLUSION: DTI can provide more information for understanding the pathophysiology of motor disability and associated sensory handicap in PVL.

[Graf's ultrasound examination method in assessment of dysplasia and congenital dislocation of infant hip].

OBJECTIVE: To discuss the application of Graf's sonographic method in assessment of developmental dysplasia and dislocation of infant hip. METHODS: 2258 infants (4516 hips) were examined and evaluated by Graf's method. RESULTS: The analysis of data showed that type I hip accounted too 78.99%, type II 20.56%, and type III and type IV 0.45%. CONCLUSION: Graf's method can provide qualitative and quantitative evaluation for hips of infants in 3 months after birth. It is an effective in developmental dysplasia of the hip (DDH) and is also useful for early treatment and follow-up of DDH.