Objective To purify pre-ribosome and ribosome of mammalian ceils using continuous sucrose density gradient ultracentrifugation.Methods Continuous sucrose density gradient was established by ultracentrifugation,and the continuous sucrose density gradient of 10％-30％ and 10％-45％ were used to extract the pre-ribosome and ribosome in mammalian cells,respectively.The mammalian cell lysis buffer was added to the established continuous sucrose density gradient.Pre-ribosome and ribosome with different sedimentation coefficients were collected and the A260 absorbance of each sample was measured.Proteins of each sample were extracted to detect the large subunit protein,RPL15 by Western Blot.Results Large subunit ribosomal protein RPL15 exists on 60S of the pre-ribosome,and also on 60S,80S and polyribosome of mature ribosome.Conclusions The continuous sucrose density gradient,which is established by the swing-out rotor,can be used to isolate the pre-ribosome and ribosome of mammalian cells rapidly.This method has the advantages of good separation effect and simple operation,which provides a good method for rapid and large amount preparation and separation of various kinds of ribosomes.

Objective To investigate the process that chromosome kinesin KIF4A promote cisplatin resistance in lung cancer cells.Methods Reverse transcription PCR (RT-PCR) and Western Blot experiments were performed to analyze the expression of KIF4A in lung cancer cells A549 and cisplatin (DDP) resistant cells A549/ DDP.Cell transfection, RNA interference (RNAi) experiments and thiazolyl blue tetrazolium bromide (MTT) assays were carried out to examine cell proliferation of A549 cells with overexpression of exogenous KIF4A and A549/DDP cells with depletion of endogenous KIF4A after cisplatin treatment.Results Expression of KIF4A in A549/DDP cells was higher than that in A549 cells.With overexpression of exogenous KIF4A, A549 cells displayed drug resistance to cisplatin.On the contrary, depletion of endogenous KIF4A in A549/DDP cells resulted in cisplatin sensitivity.Conclusions Chromosome kinesin KIF4A involves in the regulation of cisplatin resistance in lung cancer cells and KIF4A may be a potential and effective new biological target for treatment of lung cancer cisplatin resistance.

Objective To observe the therapeutic efficacy of electrical stimulation and balloon dilatation in treating cricopharyngeal achalasia after a brainstem stroke.Methods Thirty dysphagia patients with cricopharyngeal achalasia after a brainstem stroke were randomly divided into an experimental group and a control group, each of 15.The experimental group was given real-time electrical stimulation and balloon dilatation, while the control group was treated using common electrical stimulation and balloon dilatation.Results Twenty-six patients in the 2 groups returned to oral feeding after treatment.Videofluoroscopy revealed that the cricopharyngeal sphincter had relaxed and the food passed successfully when swallowing.No aspiration was observed.There was no significant difference in swallowing between the two groups, but the average treatment time, days of treatment and cost of therapy in the experimental group were significantly less than in the control group.Conclusions Either real-time electrical stimulation or common electrical stimulation combined with balloon dilatation can treat dysphagia effectively, but the former can shorten the course of treatment and lower its cost.

In the recent years, the damage of the spleen has been increased due to trauma or neoplastic diseases. Traditional view holds the point that the damaged spleen should be completely removed, but with the development of spleen surgery, the important physiological function of the spleen has been widely recognized, and partial splenectomy has been well recognized by the surgeons. This paper summarized the clinical experience in partial splenectomy and raised some technical points.

Japan is one of the main trading partners for the import and export of experimental animals in China,and its quarantine and supervision policies for the import and export of experimental animals are very detailed and strict.This article takes experimental dogs,cats,and monkeys as examples to provide an in-depth analysis of the quarantine and supervision policies for the main experimental animals exported to Japan.At the same time,it reflects on the current laws and regulations,import and export management method,standards,biosafety,breeding and management status,as well as the import and export business status of experimental animals in China.Suggestions are provided in improving the laws and regulations,import and export management method,ensuring national biosafety,improving the management level of experimental animal breeding,and promoting the import and export trade of experimental animals,in order to provide reference for comprehensively improving the production,use,and breeding management level of experimental animals in China and strengthening the trade between China and Japan.

OBJECTIVETo analyze the effect difference of wave, intensity, time and treatment frequency by orthogonal design so as to explore the optimal parameters of scalp electroacupuncture (EA) for rehabilitation effect on children of cerebral palsy.

METHODSNinety children of cerebral palsy were assigned into 9 groups by orthogonal design, 10 cases in each one. The acupoints were bilateral excitable area, foot motor sensory area, speech two area, speech three area, balance area, and intelligent nine acupoints, including Shenting (GV 24), Sishencong (EX-HN 1), and bilateral Benshen (GB 13) and Touwei (ST 8). EA was applied at bilateral excitable area and speech three area. We designed an orthogonal experiment with four factors and three levels. We studied wave (sparse wave of 2 Hz, density wave of 100 Hz, sparse and density wave of 2 Hz /100 Hz), intensity (1 mA, 2 mA, intensity based on tolerance), time (10 min, 20 min, 30 min), frequency (once a day, once every other day, twice a week). The Gesell developmental scale was used to evaluate the developmental quotient (DQ); and gross motor function measure (GMFM), motor function before and after treatment.

RESULTSThe optimal parameters for DQ and GMFM were 2 Hz/100 Hz, 20 min, once every other day. .

CONCLUSIONThe optimal parameters for cerebral palsy may be 2 Hz/100 Hz, 20 min, once every other day.