小儿腹股沟嵌顿疝术式探讨

目的 探讨经腹横纹切口腹腔内行小儿腹股沟嵌顿疝还纳修补术的疗效。方法 自2000年以来我们共收治小儿腹股沟嵌顿疝36例，全部采用经腹横纹切口腹腔内还纳修补的方法，对本方法与传统治疗方法优缺点进行对比分析。结果 本方法无副损伤，无血肿与复发。结论 经腹横纹切口腹腔内行小儿腹股沟嵌顿疝还纳修补术是一种有效的方法，可推广应用。     

Layer-specific diffusion weighted imaging in human primary visual cortex in vitro

One of the most prominent characteristics of the human neocortex is its laminated structure. The first person to observe this was Francesco Gennari in the second half the 18th century: in the middle of the depth of primary visual cortex, myelinated fibres are so abundant that he could observe them with bare eyes as a white line. Because of its saliency, the stria of Gennari has a rich history in cyto- and myeloarchitectural research as well as in magnetic resonance (MR) microscopy. In the present paper we show for the first time the layered structure of the human neocortex with ex vivo diffusion weighted imaging (DWI). To achieve the necessary spatial and angular resolution, primary visual cortex samples were scanned on an 11.7 T small-animal MR system to characterize the diffusion properties of the cortical laminae and the stria of Gennari in particular. The results demonstrated that fractional anisotropy varied over cortical depth, showing reduced anisotropy in the stria of Gennari, the inner band of Baillarger and the deepest layer of the cortex. Orientation density functions showed multiple components in the stria of Gennari and deeper layers of the cortex. Potential applications of layer-specific diffusion imaging include characterization of clinical abnormalities, cortical mapping and (intra)cortical tractography. We conclude that future high-resolution in vivo cortical DWI investigations should take into account the layer-specificity of the diffusion properties.     

Characterization and subcellular localization of an RNA silencing suppressor encoded by Rice stripe tenuivirus

Rice stripe virus (RSV) is a single-stranded (ss) RNA virus belonging to the genus Tenuivirus. RSV is present in many East Asian countries and causes severe diseases in rice fields, especially in China. In this study, we analyzed six proteins encoded by the virus for their abilities to suppress RNA silencing in plant using a green fluorescent protein (GFP)-based transient expression assay. Our results indicate that NS3 encoded by RSV RNA3, but not other five RSV encoded proteins, can strongly suppress local GFP silencing in agroinfiltrated Nicotiana benthamiana leaves. NS3 can reverse the GFP silencing, it can also prevent long distance spread of silencing signals which have been reported to be necessary for inducing systemic silencing in host plants. The NS3 protein can significantly reduce the levels of small interfering RNAs (siRNAs) in silencing cells, and was found to bind 21-nucleotide ss-siRNA, siRNA duplex and long ssRNA but not long double-stranded (ds)-RNA. Both N and C terminal of the NS3 protein are critical for silencing suppression, and mutation of the putative nuclear localization signal decreases its local silencing suppression efficiency and blocks its systemic silencing suppression. The NS3-GFP fusion protein and NS3 were shown to accumulate predominantly in nuclei of onion, tobacco and rice cells through transient expression assay or immunocytochemistry and electron microscopy. In addition, transgenic rice and tobacco plants expressing the NS3 did not show any apparent alteration in plant growth and morphology, although NS3 was proven to be a pathogenicity determinant in the PVX heterogenous system. Taken together, our results demonstrate that RSV NS3 is a suppressor of RNA silencing in planta, possibly through sequestering siRNA molecules generated in cells that are undergoing gene silencing.     

Roles of the Laodelphax striatellus Down syndrome cell adhesion molecule in Rice stripe virus infection of its insect vector

The arthropod Down syndrome cell adhesion molecule (Dscam) mediates pathogen‐specific recognition via an extensive protein isoform repertoire produced by alternative splicing. To date, most studies have focused on the subsequent pathogen‐specific immune response, and few have investigated the entry into cells of viruses or endosymbionts. In the present study, we cloned and characterized the cDNA of Laodelphax striatellus Dscam (LsDscam) and investigated the function of LsDscam in rice stripe virus (RSV) infection and the influence on the endosymbiont Wolbachia. LsDscam displayed a typical Dscam domain architecture, including 10 immunoglobulin (Ig) domains, six fibronectin type III domains, one transmembrane domain and a cytoplasmic tail. Alternative splicing occurred at the N‐termini of the Ig2 and Ig3 domains, the complete Ig7 domain, the transmembrane domain and the C‐terminus, comprising 10, 51, 35, two and two variable exons, respectively. Potentially LsDscam could encode at least 71 400 unique isoforms and 17 850 types of extracellular regions. LsDscam was expressed in various L. striatellus tissues. Knockdown of LsDscam mRNA via RNA interference decreased the titres of both RSV and Wolbachia, but did not change the numbers of the extracellular symbiotic bacterium Acinetobacter rhizosphaerae. Specific Dscam isoforms may play roles in enhancing the infection of vector‐borne viruses or endosymbionts.     

Manganese‐enhanced MRI visualizes V1 in the non‐human primate visual cortex

MRI at 7 Tesla has been used to investigate the accumulation of manganese in the occipital cortex of common marmoset monkeys (Callithrix jacchus) after administering four fractionated injections of 30 mg/kg MnCl₂ · 4H₂O in the tail vein. We found a statistically significant decrease in T₁ in the primary (V1) and secondary (V2) areas of the visual cortex caused by an accumulation of manganese. The larger T₁ shortening in V1 (ΔT₁ = 640 ms) relative to V2 (ΔT₁ = 490 ms) allowed us to robustly detect the V1/V2 border in vivo using heavily T₁‐weighted MRI. Furthermore, the dorso‐medial (DM) and middle‐temporal (MT) areas of the visual pathway could be identified by their T₁‐weighted enhancement. We showed by comparison to histological sections stained for cytochrome oxidase (CO) activity that the extent of V1 is accurately identified throughout the visual cortex by manganese‐enhanced MRI (MEMRI). This provides a means of visualizing functional cortical regions in vivo and could be used in longitudinal studies of phenomena such as cortical plasticity, and for non‐destructive localization of cortical regions to guide in the implementation of functional techniques. Published in 2009 by John Wiley & Sons, Ltd.     

The right paratracheal stripe in children

The width of the right paratracheal stripe (RPS) has been established in normal adults but not in normal children. The thymus and great vessels are relatively larger in children than in adults and could obscure or widen the RPS. We found that obscuration does occur and, therefore, the RPS is less often measurable in children than in adults. Widening by the thymus and great vessels, however, does not occur. The width of the RPS in normal children, 0.5 to 3.0 mm, is slightly less than in adults. From this study of normal children and our subsequent experience with pediatric patients, we conclude that in a child an RPS 4 mm or wider is reliable evidence of disease affecting the trachea, mediastinum, or pleura.Supported, in part, by National Institutes of Health Training Grant GM 0/272 from the National Institute of General Medical Sciences     

162例HIV-1抗体阳性血清WB带型分析

通过对本实验室１９９６－１９９８年间以ＷＢ法确认的１６２例ＨＩＶ－１抗体阳性血清ＷＢ带型分析，表明ＨＩＶ早期感染带型占确认阳性数的比例呈增长趋势，提示相关的传播途径并未得到完全有效控制；随着ＡＩＤＳ期带型所占比例的增加，预示着我省ＨＩＶ感染者逐步进入临床发病期，必须引起重视。     

Ochratoxin A as a potential etiologic factor in endemic nephropathy: lessons from toxicity studies in rats.

Various reports suggest that chronic dietary exposure to ochratoxin A (OTA), a mycotoxin frequently detected in various food items may be linked to the pathogenesis of endemic nephropathy, a chronic tubulointerstitial kidney disease which occurs in geographically limited areas of the Balkan region. OTA is a potent nephrotoxin and renal carcinogen. However, the pathological lesions observed in kidneys of rats treated with OTA appear be rather different from the clinical and pathological characteristics of endemic nephropathy. Moreover, increasing evidence suggests that OTA does not bind to DNA but induces tumors by an epigenetic, thresholded mechanism. This implies that there is a dose below which no adverse health effects are expected to occur. Based on food consumption data and OTA serum concentrations, it appears that human exposure - even in areas with relatively high dietary exposure to OTA such as endemic villages - is several orders of magnitude below doses known to cause nephrotoxicity and tumor formation in laboratory animals. While it is undoubtedly important to encourage prevention of food contamination by OTA and other mycotoxins, these observations suggest that OTA is not likely to be an etiological factor involved in BEN and indicate a need to search for new clues for the etiology of this endemic kidney disease.     

The inferior radiolucent area within the cardiac silhouette: validation as a landmark for coronary sinus catheterization

Background: Catheterization of the coronary sinus (CS) plays a preponderant role in device implantation and electrophysiology. Nevertheless, catheterization of this structure can be time-consuming and is related to operator experience. An inferior radiolucent area of the cardiac right anterior oblique (RAO) view has been suggested as a landmark to guide CS catheterization. However, the true relationship of this area with the CS ostium (CSO) has not been studied.
Methods: Thirty-five consecutive patients who underwent right coronary angiography were prospectively enrolled in the study. Fluoroscopic images of the heart in the right anterior oblique, both immediately before and during the venous phase of right coronary angiography, were recorded and digitally stored. Postprocedure measurements of the inferior radiolucent area within the cardiac silhouette and, subsequently, the distance of this area to the CSO, were performed by two independent observers.
Results: A radiolucent area of 9.5 ± 3.0 × 11.0 ± 3.4 mm was identified in the inferior annulus by the two evaluators in all patients. No significant differences in the dimensions of this area were found between the two observers. The CSO was 9.6 ± 7.2 mm superior and 0.1 ± 9.0 mm posterior to the radiolucent area and no statistically significant differences were found between the two observers.
Conclusion: An inferior radiolucent area can be identified within the cardiac silhouette in most patients in the RAO view. This area is slightly anterior and inferior to the CSO and can be used for catheterization guidance of this latter structure.     

Facilitation of Rice Stripe Virus Accumulation in the Insect Vector by Himetobi P Virus VP1

The small brown planthopper (SBPH) is the main vector for rice stripe virus (RSV), which causes serious rice stripe disease in East Asia. To characterize the virus-vector interactions, the SBPH cDNA library was screened with RSV ribonucleoprotein (RNP) as bait using a GAL4-based yeast two-hybrid system. The interaction between RSV-RNP and the Himetobi P virus (HiPV, an insect picorna-like virus) VP1 protein was identified. The relationships between HiPV and RSV in SBPH were further investigated, and the results showed that the titer of RSV was commonly higher in single insect that exhibited more VP1 expression. After the VP1 gene was repressed by RNA silencing, the accumulation of RSV decreased significantly in the insect, whereas the virus acquisition ability of SBPH was unaffected, which suggests that HiPV VP1 potentially facilitates the accumulation of RSV in SBPH.