Research of reversal effect of PESV to multi-drug resistance of leukemia stem cell / 中国中药杂志

Using the BALB/c mouse multidrug resistance model of leukemia, the effect of peptide extract from scorpion venom (PESV) to the upstream signal factors of P-gp of MDR leukemia stem cells on the mouse tumor block was observed, and the mechanism of PESV to reverse the MDR of LSC was studied. At the same time, the expression of P-gp, MDR1 mRNA and PI3-K, NF-κB were respectively detected through flow cytometry, RT-PCR, Western blot and Elisa, and the mouse liver, spleen were examined via histopathological methods. The results of the experiment were as follows: mice of the control group didn't show any obvious changes, while mice of the other six groups all showed arched back, emaciation, liver swell, and inflammation was found in all liver tissue. The expression level of P-gp and PI3K on the LSC membrane of mouse tumor block was down-regulated; the expression of MDR1 mRNA in the cytoplasm was obviously down in the PESV low dose group, and which was inordinately up in the middle dose group and the high dose group. The expression level of NF-κB in the leukemia stem cell nucleus remarkably decreased. PESV had a outstanding role of down-regulating PI3K, NF-κb, MDR1 which were all upstream factors of P-gp, and to a certain degree enhanced the sensitivity of LSC to ADM. Therefore, this experiment explained one of the mighty mechanism of PESV to reverse MDR of LSC, and provided a foundation to further study of combinational anti-cancer effects of PESV.

Impacts of acupuncture at Hegu (LI 4) on facial EMG in rhesus monkeys under the physiological state / 中国针灸

<p><b>OBJECTIVE</b>To observe the specificity relationship between acupuncture at "Hegu" (LI 4) and the facial muscular movement in rhesus monkeys under the physiological state by using neuromuscular electrical measurement technique.</p><p><b>METHODS</b>Eighteen rhesus monkeys were randomized into a Hegu group, a Houxi group and a Waiguan group, 6 monkeys in each one. Under the physiological state, EMG was detected on the frontal muscle, zygomatic muscle and orbicular muscle before and after acupuncture at different acupoints. The impacts of acupuncture on the facial EMG were studied and compared among different acupoints.</p><p><b>RESULTS</b>With acupuncture at "Hegu" (LI 4), the latency was reduced (P < 0.01) and the peak value and area were increased (P < 0.05, P < 0.01) in the frontal EMG; the area and the peak value were increased (P < 0.01, P < 0.05) and latency was reduced (P < 0.05) in the zygomatic EMG; the frequency was increased (P < 0.01) and the latency was reduced (P < 0.05) in the orbicular EMG. Before and after acupuncture at "Hegu" (LI 4), the change rates of EMG frequency, peak value, area and latency on the frontal, zygomatic and orbicular muscles were higher than those at "Houxi" (SI 3) and "Waiguan" (TE 5) (P < 0.05, P < 0.01) separately.</p><p><b>CONCLUSION</b>The relative specificity presents between Hegu (LI 4) and facial muscular movement.</p>

Establishment and identification of CML model via injection of K562 cells into the murine caudal vein / 中国实验血液学杂志

This study was purposed to establish and identify the model of extramedullary infiltration of CML-NOD/SCID mice. 24 mice were irradiated with 270 cGy of (137)Cs and absorbed dose rate 80 cGy/min, and were randomly divided into test group I, test group II and control group. The mice in test group I and test group II were injected with 5×10(6) and 1×10(7) K562 cells per mouse respectively, the mice in control group were injected with 0.2 ml of normal saline. The general situation and survival time of these mice were monitored, the extramedullary infiltration of leukemia cells was detected by histopathology examination and RT-PCR. The results indicated that at 4 - 8 weeks after injection, all the mice of group I and group II displayed extramedullary infiltration, suggesting that CML/NOD-SCID model was successfully established. It is concluded that the model of extramedullary infiltration of CML/NOD-SCID mice can be established by injection K562 cells into caudal vein, and can be confirmed by histopathologic examination and detection of BCR-ABL fusion gene using RT-PCR.

Influence of polypeptide extract from scorpion venom on PI3K and p-Akt signaling protein expression and cell proliferation of K562 cells / 中国实验血液学杂志

This study was aimed to investigate the effect of polypeptide extract from scorpion venom (PESV) on PI3K, p-Akt signal protein regulating K562 cell apoptosis and its mechanism. The K562 cells were cultured with PESV for different time, the cell growth curve was determined by MTT method, the levels of PI3K and p-Akt proteins were detected by Western blot. The results showed that as compared with control group, the apoptosis rate of K562 cells treated with PESV increased, the levels of PI3K and p-Akt expression decreased. It is concluded that the PESV inhibits the proliferation and promotes the apoptosis of K562 cells probably through suppressing the expression of PI3K and p-Akt signal proteins.

Location of exogenous α-crystallin in retinal ganglion cells / 中华实验眼科杂志

Background There is no effective method to regenerate the optic nerve after injury. It has been recently reported that α-crystallin could promote the survive rate and axon regeneration of retinal ganglion cells (RGCs) effectively. However,the molecular mechanism is not clear. Objective This study was to identify the site of RGCs where the exogenous α-crystallin bind to. Methods RGCs was isolated from retinas of two 2-day-old Long Evans rats and primarily cultured. The positive rate of the RGCs was assessed by counting the number of positive cells for fluorescently-labeled thy1. 1 and cy3 under the fluorescence microscope. The biotinylated exogenous α-crystallin was evaluated by direct coloration and the activity of molecular chaperones was measured by insulin test.After identifying the success of biotinylation along with the activity of molecular chaperones,biotinylated α-crystallin was co-incubated with RGCs and the cells then were reacted to fluorescently labeled avidin for the observation of binding site of exogenous α-crystallin under the laser confocal microscope. Results RGCs of 94% were survived through primary culture. The coloration of biotinylated α-crystallin labeled by the direct coloration method was more intensive, and the value of A450 descended as the decrease of biotinylated α-crystallin concentration,indicating that the α-crystallin was biotinylated successfully. The activity of molecular chaperones of biotinylated α-crystallin was significantly strong but no significant change after being biotinylated after co-incubation of RGCs with biotinylated α-crystallin. Laser confocal microscope examination revealed that co-incubated RGCs with biotinylated α-crystallin showed the red fluorescence on membrane and axon of RGCs rather than cytoplasm and nucleus. The absent response was seen in the control group. Conclusion Exogenous α-crystallin can specifically combine with the membrane of RGCs to play the biological function,but its binding mode and mechanism need further study.