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Xiao-Dong Wu,
Yu Zhu, Wen-Jun Chen,
Xiang Jin,
Nicholas Tsai,
Huang-Yuan Huang,
Jian-Yuan Jiang,
Dong-Qing Zhu,
Pei-Ying Li,
Robert Weber,
Wen Yuan,
Hua-Jiang Chen
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ABSTRACT: The objective of this study was to detect cerebral potentials elicited by proximal stimulation of the first sacral (S1) nerve root at the S1 dorsal foramen and to investigate latency and amplitude of the first cerebral potential. Tibial nerve SEP and S1 nerve root SEP were obtained from 20 healthy subjects and 5 patients with unilateral sciatic nerve or tibial nerve injury. Stimulation of the S1 nerve root was performed by a needle electrode via the S1 dorsal foramen. Cerebral potentials were recorded twice to document reproducibility. Latencies and amplitudes of the first cerebral potentials were recorded. Reproducible cerebral evoked potentials were recorded and P20s were identified in 36 of 40 limbs in the healthy subjects. The mean latency of P20 was 19.8 ± 1.6 ms. The mean amplitude of P20-N30 was 1.2 ± 0.9 μV. In the five patients, P40 of tibial nerve SEP was absent, while well-defined cerebral potentials of S1 nerve root SEP were recorded and P20 was identified from the involved side. This method may be useful in detecting S1 nerve root lesion and other disorders affecting the proximal portions of somatosensory pathway. Combined with tibial nerve SEP, it may provide useful information for diagnosis of lesions affecting the peripheral nerve versus the central portion of somatosensory pathway.
European Spine Journal 05/2011; 20(10):1613-9. · 1.97 Impact Factor
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ABSTRACT: To put some improvements to the traditional transforaminal lumbar interbody fusion (TLIF) and discuss its clinical significance.
Completed the traditional posterior lumbar interbody fusion (PLIF) and TLIF procedure in 12 fresh cadavers, dissect further to expose the surrounding anatomical structures, and put the modified TLIF surgery according to the anatomical findings. And simulated the operation in 12 fresh cadavers, analyzed its feasibility and potential advantages.
The early anatomical study found that the related nerve root was in a state of high tension and certain risk of injury when completed the traditional PLIF and TLIF surgery, and found certain operational area between the superior articular process and the midline structures of the spinous processes and interspinous ligaments. Put the modified TLIF surgical approach according to the anatomical findings, which the operating area is located in PLIF outside and TLIF inside. As the following words: Take a posterior-middle incision, preserve the supraspinous and interspinous ligaments, and the spinous processes, dissect the bilateral paravertebral muscle, expose lamina and facet joints, not including transverse process, and remove unilateral inferior two third lamina, inferior articular process and expose the articular surface of the superior articular process, then dispose the intervertebral space for interbody fusion obliquely in the unilateral approach. Successfully completed the modified TLIF procedure in 12 fresh cadavers, the results showed that the technique has the following advantages. (1) Only remove unilateral inferior two third lamina and inferior articular process, preserve the supraspinous and interspinous ligaments, and the spinous processes, not expose the transverse process. (2) Both central canal, and lateral recess and nerve root canal of the operative side can be decompressed effectively simultaneously. (3) Avoid excessive traction to the thecal sac and traversing nerve roots and decrease the injury rate due to the reservation of the midline structures and the oblique manipulation, and less injury rate of the exiting nerve root, because of not necessary to expose it routinely.
The modified TLIF is safe and feasible, could effectively reduce the nerve roots injuries. Maybe it's a better choice for most of the Chinese patients at present.
Zhonghua wai ke za zhi [Chinese journal of surgery] 07/2009; 47(14):1100-3.
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ABSTRACT: To explore the possible regulatory role of chlorophyllase (Chlase) in chlorophyll (Chl) degradation during leaf senescence, RNAi Arabidopsis (Arabidopsis thaliana) plants were constructed to repress the expressions of AtCLH1 and/or AtCLH2. Transcript levels of AtCLH1 and/or AtCLH2 were dramatically lowered and Chlase activity was correspondingly inhibited, but the Chl degradation kinetics was not affected in the RNAi plants. Results of further analysis indicated that the Chl a/b ratio decreased in AtCLH1 RNAi lines, in comparison with the increasing Chl a/b ratio in the wide type during leaf senescence. In addition, an induced Chlase activity was consistently detected at the initial stage of senescence in all the plants examined. In contrast, transcript levels of both AtCLH1 and AtCLH2 decreased dramatically upon the initiation of senescence in both the wide-type and the RNAi plants. Interestingly, compared with the wide type, lower but still significant transcript levels of the RNAi targeted Chlase gene(s) were sustained during the whole period of dark incubation in all the three RNAi lines examined, indicating the functioning of some compensatively regulating mechanism. Based on these results, along with related reports, we conclude that Chlase might be required at the initial stage of leaf senescence, quite likely playing a role in converting Chl b to a.
Zhi wu sheng li yu fen zi sheng wu xue xue bao = Journal of plant physiology and molecular biology 01/2008; 33(6):596-606.
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ABSTRACT: Chlorophyllase (EC 3.1.1.14) is involved in the first step of chlorophyll degradation. Isolation of chlorophyllase genes greatly facilitates characterization of chlorophyllase properties and elucidation of molecular regulation of their in vivo activities. There are two chlorophyllase genes, AtCLH1 and AtCLH2, in Arabidopsis thaliana. The in vivo roles of AtCLH1 have been reported previously. However, few studies have been carried out on AtCLH2. Here, we show that purified recombinant Chlase2, encoded by AtCLH2, exhibits in vitro chlorophyllase activity. Interestingly, “activation” of in vitro activity of the recombinant Chlase2 required higher concentrations of a detergent or a polar solvent. To determine its activity in vivo, the expression of AtCLH2 was inhibited by RNA interference. RNAi plants showed decreased contents of chlorophyllide without a substantial change in the total amount of the extractable chlorophyll and consequently presented lower chlorophyllide to chlorophyll ratios in their leaves. In addition, the two AtCLHs exhibited differential expression patterns. Our results suggest that AtCLH2 might play a distinctive role in chlorophyll catabolism in vivo.
Journal of Integrative Plant Biology 04/2007; 49(4):531 - 539. · 2.53 Impact Factor
