Gene targeted mutagenesis and replacement can be used to modify gene sequence in genomic background without position effect or insertion inactivation in transgenic plants. Targeted mutagenesis organism has little biosafety concerns free of transgenes or marker genes. Gene targeted mutagenesis and replacement in high plants now appears to be a potential tool for gene functional analysis in situ, crops genetic improvement and molecular design. Zinc finger nuclease(ZFN)is most important and would be widely used in gene targeted mutagenesis and replacement through introducing double-strand breaks in genome. Strategies for gene targeted mutagenesis and replacement in plants is discussed. ZFN is described in detail from its structure, operation model and application in plants. Developmental prospect of ZFN in plant gene targeted mutagenesis and replacement is also discussed.

OBJECTIVETo explore the underwater decompression schedule for 100 m Trimix conventional diving operations and evaluate its safety through a simulated rabbits Trimix conventional diving.

METHODSAccording to the Haldane theory, the assumed time units, the classification of tissue compartments, the nitrogen super-saturation safety coefficient and the selection of methods used for the calculation of the simulated 100 m Trimix conventional diving schedule were properly selected, and the calculating method for the dive decompression schedule was thus firmly established. In our experiments, five tissue compartments were selected during the calculation of decompression schedule: 5 min, 10 min, 20 min, 40 min and 75 min, and the nitrogen super-saturation safety coefficient was calculated by 1.6. Eight New Zealand rabbits were performed a simulated 100 m Trimix dive program which was established according to the Haldane theory, and eight rabbits for intact group. The tissues wet/dry ratio and ethology were detected and observed before and after the simulated diving to evaluate the safety of decompression schedule.

RESULTSBy using the developed underwater decompression schedule, abnormal ethology changes in rabbits could not be observed after compression and decompression to the surface; and the tissues wet/dry ratio of simulated diving rabbits had no significant changes compared with the intact group (P > 0.05).

CONCLUSIONThe decompression schedule calculated by Haldane theory seemed to be safe and reliable, the diving breathing gas concentration did not cause oxygen toxicity and nitrogen narcosis among the dive rabbits, and dive efficiency was greatly improved by using enriched oxygen gas in UPTD safety range during decompression.

Animal Experimentation ; Animals ; Decompression ; Diving ; Helium ; Nitrogen ; Oxygen ; Rabbits

Numerous interpolation-based methods have been described for reducing metal artifacts in CT images, but due to the limit of the interpolation methods, interpolation alone often fails to meet the clinical demands. In this paper, we describe the use of quartic polynomial interpolation in reconstruction of the images of the metal implant followed by linear interpolation to eliminate the streaks. The two interpolation methods are combined according to their given weights to achieve good results.
Algorithms ; Artifacts ; Dental Prosthesis ; Humans ; Radiographic Image Interpretation, Computer-Assisted ; methods ; Tomography, X-Ray Computed ; methods

Objective To explore the effects of acupuncture on pruritic behaviors, expression of 5-HT neurons in medulla oblongata and 5-HTR2B on mice with chloroquine-induced pruritus; To discuss the mechanism of action of acupuncture in chloroquine-induced pruritus. Methods A non-histamine-dependent pruritus model was prepared by subcutaneous injection of chloroquine into the back of the neck. Forty C57B/6J mice were randomly divided into model-acupuncture group, model-non-acupuncture group, normal saline group and blank control group, with 10 mice in each group. After modeling, acupuncture was given in Xuehai, Quchi and Hegu on both sides. The plug and twist way was used to stimulate, once a day, three times. Model-non-acupuncture group received no acupuncture. Normal saline group received the neck injection of saline in the back. Blank control group received no treatment. Behavioral changes were observed, and immunofluorescence technique and Western blot were used to test the expression of 5-HT neurons and 5-HTR2B in medulla oblongata neurons. Results The number of scratches in model-acupuncture group and model-non-acupuncture group was obviously more than normal saline group and blank control group (P<0.05). The number of scratches in model-acupuncture group was lower than that of model-non-acupuncture group (P<0.05). The expression of 5-HT in medulla oblongata neurons was unclear in both normal saline group and blank control group. The expression of 5-HT neurons in medulla oblongata significantly increased in model group, which decreased after acupuncture. The expression of 5-HTR2B of model group was significant higher than normal saline group and blank control group (P<0.01). Compared with model-non-acupuncture group, the expression of 5-HTR2B in model-acupuncture group significant decreased (P<0.01). Conclusion Acupuncture can significantly inhibitscratching behaviors in mice induced by chloroquine, and the mechanism may be realized by decreasing the expression of 5-HT neurons and 5-HTR2B in medulla oblongata neurons.

Objective To investigate the histopathological and ultrastructural changes in the corneal epithelium in TgAPPswePS1 transgenic mice.Methods TgAPPswePS1 transgenic mice were randomly divided into experimental group (A and B sub-group) and control group.There were 15 APPswe/PSEN1dE9 transgenic mice (15-18 months old) with Alzheimer's disease (AD) in the experimental A group,and 15 APPswe/PSEN1 dE9 transgenic AD mice (8 months old) mice in the experimental B group,as well as 10 wild-type mice (8 months old) in the control group.Then,the histopathological and ultrastructural changes and the expression of amyloid β-protein (Aβ) in the corneal epithelium of the mice were detected,and finally,the apoptosis of corneal epithelial cells were observed by TUNEL assay.Results The thickness of corneal epithelium in the control group,A and B sub-group of the experimental group was (23.567 ± 2.123) μm,(15.456 ± 1.439) μm and (20.104 ± 1.763) μm,respectively.Meanwhile,murine corneal epithelial cells presented the histopathological changes of disorderly arrangement,decreased layers of cells and irregular morphology in the experimental group compared with the control group.Under transmission electron microscope,the microvilli on the surface of corneal epithelium was flat and significantly decreased in the A and B sub-group when compared with the control group.Moreover,Aβ positive expression in the experimental group was significantly upregulated compared with the control group;and the apoptotic number of the corneal epithelium in the B sub-group [(5.631 ± 2.471) cells] was smaller than that in the A sub-group [(16.329 ±3.542) cells],with the significant difference(P ＜ 0.05).Conclusion There are changes in the histopathology and ultrastructure of the corneal epithelium and the expression of Aβ in TgAPPswePS1 transgenic mice compared with wild-type mice,which are associated with the age of mice.

[Objective]To evaluate the practicality of non-mydriatic digital fundus camera in the remote screen of diabetic retinopathy for community residents.[Methods]Ninety-two patients(184 eyes)with type 2 diabetes mellitus have been taken 1-field and 5-field non-mydriatic fundus photography and examination in mydriatic fundus by pre-placed-mirror ophthalmoscopy by a ophthalmologist,the results were sent to the hospital with a computer programs. A specialist evaluates the consistency of detectable rate of diabetic retinophathy(DR)among the 3 methods.The time of tak-ing 1-field and 5-field non-mydriatic fundus photography is compared.[Results]All the three methods show good consis-tency in detectable rate of DR compare with each other,the κ value is 0.89 for 1-field non-mydriatic fundus photography and examination in mydriatic fundus by preplaced-mirror ophthalmoscopy,0.95 for 1-field and 5-field non-mydriatic fundus photography and 0.95 for 5-field non-mydriatic fundus photography and examination in mydriatic fundus by pre-placed-mirror ophthalmoscopy,respectively. The 1-field non-mydriatic fundus photography spent less time compares with 5-field non-mydriatic fundus photography(55.4±5.8 vs 405.9±68.5 s,P<0.01).[Conclusion]The remote screen for diabetic retinopathy in community based on non-mydriatic digital fundus camera is worth promoting,we suggest 1-field non-mydriatic fundus photography as a screen method.

Objective To investigate the association between interleukin-10 (IL-10) gene promoter microsatellite polymorphisms and the susceptibility to hepatitis B virus infection in Han,Yi and Yao ethnicities in GuiZhou province.Methods 500 volunteers were selected from Guizhou province.Ailelic frequency of IL-10.G and IL-10.R loci was identified by short tandom repeat polymerase chain reaction.The relativity between allelic frequency and HBV infection was analyzed.Results Genotype data from H-W analysis on all the IL-10 polymorphisms indicated that it was a random distribution.Very high HBV infection rates were found in the native ethnic minorities of Guizhou province.The overall HBV infection rate among the total population was 67.00％,with the HBV infection rates of Yi nationality in Weining,Yi nationality in Qianxi,Yao nationality in Libo and Han nationality in Libo as 51.85％,42.86％,79.52％ and 84.30％,respe~vely.The polymorphisms distribution of IL- 10.G and IL- 10.R were statistically different among the ethnic groups (P＜ 0.05 ).The polymorphisms distribution of IL-10.R had no significant difference between HBV infection group and non-infection group,as well as among HBV natural removal group and non-infected group in all the ethnic groups.The frequency of IL-10.G 459 bp (19CA) was significantly higher in non-infection group than in the infected group (P＜ 0.05 ).The frequency of IL-10.G 471 bp (25CA) was significantly higher in the non-infection group than in the HBV natural removal group(P＜0.05).The polymorphisms distribution of IL-10.G did not show significant difference between the HBV infection group and the HBV natural removal group in all the ethnic groups.We did not find any differences in allelic and genotypic frequencies of IL-10.G between infection group and non-infection group in Yi nationality in Weining,and Yao nationality in Libo (P＞0.05),as well as HBV natural removal group and non-infected group (P＞0.05).Conclusion The polymorphisms distribution of IL-10.R and IL-10.G did not show significant difference in Yi,Yao and Han ethnics population living in Guizhou province.IL-10.G seemed to influence the susceptibility of HBV infection in Han,Yao and Yi ethnics population of Guizhou province.

OBJECTIVETo investigate the clinical, pathological and immunohistochemical features of vulvar intraepithelial neoplasia (VIN).

METHODSAccording to the 2004 modified terminology of International Society for the Study of Vulvovaginal Diseases (ISSVD), the cases were diagnosed as VIN from patients who had performed vulvar biopsy in Beijing Wuzhou Women's Hospital from February 2009 to December 2011, which were reclassified as usual VIN and differentiated VIN. The clinical and pathological studies were conducted respectively. MaxVision immunohistochemical staining was used to detect the expression of Ki-67, p16 and p53 proteins.

RESULTSThere were 20 cases of VIN in 237 patients, and the incidence of VIN was 8.4% in all of contemporary vulvar biopsy. In 17 cases of usual VIN, mean age was 29.6 years, the lesion typically presented with atypical cells involving almost all layers of the epithelium, which was equivalent to the high-grade squamous intraepithelial neoplasia of cervix. Immunohistochemistry for Ki-67 and p16 was strongly positive in usual VIN. High risk human papillomavirus (HPV) detection was also positive. The incidence of differentiated VIN was less than usual VIN, and there were only 3 cases in this study. In differentiated VIN, patients aged over 50 years, with mean of 53.7 years, and the lesion most commonly presented with lichen sclerosis background. There were epithelial thickening and extending, and parakeratosis, and atypia was strictly confined to the basal and parabasal layers of the epithelium where the cells enlarged with abundant eosinophilic cytoplasm, presented with prominent nucleoli, increased cellularity and abnormal keratinization. In differentiated VIN, p53 was strongly positive, Ki-67 and p16 immunohistochemical expression was confined to the basal layer only.

CONCLUSIONSVIN is a precursor of invasive squamous cell carcinoma of the vulva. The modified terminology of ISSVD classifies VIN as high-grade lesions. Definitive pathological diagnosis of VIN plays an important role in its timely treatment and the prevention of vulvar carcinoma.

Adult ; Carcinoma in Situ ; metabolism ; pathology ; virology ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Female ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Middle Aged ; Papillomavirus Infections ; pathology ; Tumor Suppressor Protein p53 ; metabolism ; Vulvar Neoplasms ; metabolism ; pathology ; virology ; Young Adult

OBJECTIVETo evaluate the roles of enteric nervous system neurotransmitters, nitric oxide (NO), substance P (SP) and vasoactive intestinal polypeptide (VIP), and interstitial cells of Cajal (ICC) in the colon in slow transit constipation in rats.

METHODSThirty-two healthy Wistar rats were randomly assigned to control and constipated groups. In the constipated group, the rats were daily administered with diphenoxylate (8 mg/kg) to develop slow transit constipation, while the control rats were fed with water. The number and the weight of fecal granule and the body weight of rats were recorded every 5 days for 90 days. Transit functions of intestinal movement were examined by an activated charcoal suspension pushing test one week after stopping the administration of diphenoxylate. The levels of NO and SP in the colonic mucosa were measured by nitrate reductase methods and ELISA respectively. The distribution of VIP and ICC positive cells confirmed with symbolic c-kit+ cells in the colonic wall were observed by immunohistochemical methods.

RESULTSThe daily number of fecal granule in the constipated group was significantly less than that in the control group (P<0.01). The mean weight of each fecal granule in the constipated group was significantly higher than that in the control group (P<0.01). The discharge time of the first granule of black faeces in the constipated group (430.2+/- 132.1 min) was significantly longer than that in the control group (337.2+/- 74.7 min; P<0.05). There were no significant differences in NO and SP levels and the density of VIP positive cells in the distal colonic segment between the two groups. The number of c-kit+ cells in the distal colonic wall in the constipated group was significantly reduced compared with that in the control group (P<0.05).

CONCLUSIONSThe reduction of ICC number in the distal colon may be contributed to the pathogenesis of slow transit constipation in rats.

Animals ; Body Weight ; Coiled Bodies ; Colon ; cytology ; innervation ; Constipation ; etiology ; Male ; Neurotransmitter Agents ; physiology ; Nitric Oxide ; analysis ; physiology ; Proto-Oncogene Proteins c-kit ; analysis ; Rats ; Rats, Wistar ; Substance P ; analysis ; physiology ; Vasoactive Intestinal Peptide ; analysis ; physiology

Objective To investigate the association of IL-10 gene promoter polymorphism with susceptibility to hepatitis B viral infection in Han, Yi and Yao ethnic groups from Guizhou province.Methods Five hundred volunteers from Guizhou province were selected to undertake PCR-RFLP for detection of IL-10 gene promoter -592 polymorphisim. Results The genotypic distributions of IL-10-592 were 32.53%- 51.43% (AA),40.74%-54.82% (AC),5.79%-18.52% (CC) whereas the allelic frequencies were 59.94% -72.38% for the A allele, and 27.62%-40.06% for the C allele in Han, Yi and Yao ethnics from Guizhou. The distributions of allele and genotype frequencies of IL-10-592 were statistically different between Yao ethnic in Libo and Yi ethnic in Qianxi, Yao ethnic in Libo and Han ethnic in Libo, Yi ethnic in Qianxi and Yi ethnic in Weining, Yi ethnic in Weining and Han ethnic in Libo (P ＜0.05). IL-10-592 polymorphism was associated with HBV infection in Yi ethnic in Qianxi and the whole population. Conclusion IL-10-592 gene polymorphisms influenced the susceptibility to HBV infection in Han, Yao, Yi sub-populations in Guizhou. Result of the study suggested that IL-10-592 gene polymorphisms might serve as a risk factor to HBV infection.