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991.
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Purpose

To explore how the use of a laser needle-knife affects vertebroarterial morphology and protein expression of PI-3K, AKT and VEGF in the carotid artery of a rabbit model of cervical spondylotic arteriopathy (CSA), and to determine its primary treatment mechanism.

Methods

The CSA rabbit model consisted of 30 rabbits with CSA that were randomly divided into a model group (n?=?10), an acupuncture group (n?=?10) and a laser needle-knife group (n?=?10) plus a further 10 wild type rabbits placed into a normal group. Rabbits in the acupuncture group were treated by needling the Fengchi (GB 20) and Jiaji (EX-B2) acupoints, while those in the laser needle-knife group were treated with a laser needle-knife on the Jiaji (EX-B2) near the spinous process of the fifth cervical vertebra, the rabbit in both groups immobilized during treatment. Rabbits in the other two groups received no treatment, but were immobilized for a similar duration. The morphology of the right vertebral artery and the distribution of pore size before and after treatment were compared using BET and SEM, and the protein expression of PI-3K, AKT and VEGF in the carotid artery of the four groups measured using Western blot analysis.

Results

The pore diameter and specific surface area of the right vertebral artery increased after treatment, as did the number of micropores. Compared with the normal group, the protein expression of PI-3K, AKT and VEGF in the carotid artery of the model group was significantly lower (P?<?0.05), while that of the laser needle-knife group was significantly higher (P?<?0.05 and P?<?0.01). In addition, rabbits from the acupuncture and laser needle-knife groups demonstrated significantly higher levels of protein expression of PI-3K and VEGF in the carotid artery compared with the model group (P?<?0.05 and P?<?0.01).

Conclusions

By promoting micrangium hyperplasia within the vertebral artery of rabbits with CSA, treatment with a laser needle-knife modified the protein expression of PI-3K, AKT and VEGF, suggesting that laser needle-knife therapy possibly treats CSA though these signaling pathways.  相似文献   
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Objective

To determine the effect of laser needle-knife on PI-3K, AKT and VEGF mRNA expression of vertebral arteries in a rabbit model of cervical spondylotic arteriopathy (CSA) and the mechanism of action involved.

Methods

Forty healthy general-grade rabbits were divided into a normal control group, model group, acupuncture group, and laser needle-knife group (n?=?10 rabbits per group), and the CSA rabbit model was established in all but groups but the normal control group. CSA model rabbits in the acupuncture group were treated by acupuncture at the Fengchi (GB 20) and Cervical Jiaji (EX-B 2) points, whereas rabbits in the laser needle-knife group were treated with laser needle-knife targeting the Jiaji points near the C5 spinous process. Rabbits in the normal control and model groups were fixed using similar methods. Behavioral characteristics of all rabbits were evaluated before and after treatment. Peak systolic velocity (PSV) of the right carotid and vertebral arteries in each group were examined using beside B ultrasound, and PI-3K, AKT, VEGF mRNA expression in vertebral arteries were determined by real-time PCR.

Results

The behavioral signs of rabbits were improved after treatment in both the acupuncture and laser needle-knife groups. In comparison with control group, PSV of right carotid arteries in acupuncture group and laser needle-knife group were enhanced significantly (P?<?0.05 and P?<?0.01), PSV of right vertebral arteries in acupuncture group and laser needle-knife group were enhanced significantly too (P?<?0.01 and P?<?0.05). PI-3K mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group (P?<?0.01, P?<?0.05). AKT mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group (P?<?0.01). VEGF mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group too (P?<?0.01, P?<?0.05). No significant differences were found in PI-3K, AKT and VEGF mRNA expression levels among acupuncture and laser needle-knife groups (P?>?0.05).

Conclusion

Laser needle-knife could effectively intervene the mRNA expression of PI-3K, AKT and VEGF, this may be one of the mechanisms of the effect of laser needle-knife in treating CSA in rabbits.  相似文献   
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Changes in labile carbon (LC) pools and microbial communities are the primary factors controlling soil heterotrophic respiration (Rh) in warming experiments. Warming is expected to initially increase Rh but studies show this increase may not be continuous or sustained. Specifically, LC and soil microbiome have been shown to contribute to the effect of extended warming on Rh. However, their relative contribution is unclear and this gap in knowledge causes considerable uncertainty in the prediction of carbon cycle feedbacks to climate change. In this study, we used a two‐step incubation approach to reveal the relative contribution of LC limitation and soil microbial community responses in attenuating the effect that extended warming has on Rh. Soil samples from three Tibetan ecosystems—an alpine meadow (AM), alpine steppe (AS), and desert steppe (DS)—were exposed to a temperature gradient of 5–25°C. After an initial incubation period, soils were processed in one of two methods: (a) soils were sterilized then inoculated with parent soil microbes to assess the LC limitation effects, while controlling for microbial community responses; or (b) soil microbes from the incubations were used to inoculate sterilized parent soils to assess the microbial community effects, while controlling for LC limitation. We found both LC limitation and microbial community responses led to significant declines in Rh by 37% and 30%, respectively, but their relative contributions were ecosystem specific. LC limitation alone caused a greater Rh decrease for DS soils than AMs or ASs. Our study demonstrates that soil carbon loss due to Rh in Tibetan alpine soils—especially in copiotrophic soils—will be weakened by microbial community responses under short‐term warming.  相似文献   
995.
Exploring the Diversity of Plant Metabolism   总被引:1,自引:0,他引:1  
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