Pseudorabies virus(PRV)is the etiological agent of pseudorabies in pigs,which is char-acterized by dyspnea,reproductive disorders,and neurological diseases,and it spreads widely a-round the world.Since 2011,the newly emerged PRV variants have resulted in poor immunity pro-tection of traditional vaccine strains,and the original method of vaccine strain preparation is time-consuming and labor-intensive.Therefore,it is urgently needed to develop an efficient screening method of the vaccine strain at present.Using CRISPR/Cas9 gene editing technology in this study,two single guide RNAs(sgRNA)were designed targeting the virulence gene TK of PRV variant strain CH/JX/2016,and then the enhanced green fluorescent protein the reporter(EGFP)gene was inserted at the TK locus by a homologous repair plasmid.After multiple rounds of plaque puri-fication,the rPRV-ΔTK/EGFP strain was obtained.The results showed the cleavage efficiency of the two sgRNAs was extremely high.The preparation of rPRV-ΔTK/EGFP strain was succeed af-ter only three rounds of purification,and the EGFP expressed normally.The CRISPR/Cas9 system can edit the PRV gene simply,rapidly,and efficiently,and exhibits great potential in the construction of vaccine candidate strains.Meanwhile,the rescued rPRV-ΔTK/EGFP strain not only could be used as a tracer strain in PRV variant infection progresses,but also for subsequent antivi-ral drug screening.

Objective: To investigate the relationship between urinary monohydroxylated metabolites of hydroxyl polycyclic aromatic hydrocarbons (OH-PAHs) and lung function, as well as the role of oxidative stress in these associations, so as to provide a scientific basis for air pollution control and policy formulation. Methods: A panel study was carried out among 45 young healthy adults. Four follow up surveys and health examinations were conducted from November 2017 to October 2018 to measure lung function parameters [forced vital capacity (FVC), second forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), FEV1/FVC, and forced expiratory flow between 25% and 75% vital capacity (FEF 25%~75% )], markers of exposure to 7OHPAHs [∑ 7OH PAHs], and markers of oxidative stress[8 hydroxy 2 deoxyguanosine (8 OHdG) and 8 isoprostaglandin F 2α (8 iso PGF 2α )]. The relationship between urinary PAH metabolites and lung function was quantified by linear mixed effects models. Mediation analysis was performed to assess the role of oxidative stress in the relationship between OH PAHs and lung function. Results: The median values of FVC, FEV1, FEVI/FVC, PEF, and FEF 25%-75% were 4.37 L, 3.58 L, 83.00%, 4.38 L/s, and 3.32 L/s, respectively. The results showed that each 1 unit increase in log transformed value of 2 Hydroxyfluorene (2 OHFlu) was associated with a 5.05% decrease ( β %=-5.05%，95% CI =-8.85%--1.09%) in FVC, 4.15% decrease ( β %=-4.15%，95% CI =-7.94%- -0.22% ) in FEV1 and 5.87% decrease ( β %=-5.87%，95% CI =-11.35%--0.05%) in FEF 25%-75% , respectively. Each 1 unit increase in log transformed values of 2 OHFlu and 9 Phenanthrol (9 OHPhe) was associated with a 7.03% decrease ( β %=-7.03%，95% CI =-12.60%--1.11%) and a 7.08% decrease ( β%=-7.08%，95% CI =-13.50%--0.17%) in PEF, respectively. Additionally, urinary ∑ 7OH PAHs had a positive correlation with the levels of urinary 8 OHdG and 8 iso PGF 2α ( r =0.64, 0.69, P <0.01). Meanwhile, the levels of 8 OHdG mediated 17.06% and 15.71% of the association between 2 OHFlu with FVC and FEV1. Conclusion The finding reveales a negative relationship between urinary OH PAHs and lung function among young healthy adults. The 8 OHdG plays a mediated role in the correlation of 2 OHFlu with FVC and FEV1. Active relevant policies are needed to control air pollution and maintain the healthy living conditions of young people.

Objective: To explore the association between urinary metals and lung function among college students, and to provide a theoretical basis for related research on metal exposure and lung function injury. Methods: A total of 45 healthy college students were recruited from North China University of Science and Technology in Caofeidian between 2017-2018. During the four seasons, information was obtained from questionnaires and physical examinations, lung function parameters were assessed, including FVC, FEV1, PEF, FEV1/FVC and FEF 25-75 , and morning urine samples were collected simultaneously. The urinary levels of 15 metals were measured by inductively coupled plasma mass spectrometry (ICP/MS); a Kruskal Wallis H test was used to compare differences in urinary metals during the four seasons; and a mixed effect model was used to assess correlations between urinary metals and lung function. Results: There were significant differences in the levels of urinary chromium, iron, nickel, copper, zinc, arsenic, selenium, selenium, molybdenum, cadmium, antimony and lead from 15 metals over the four seasons ( H =9.79- 20.61 , P <0.05). The differences observed in five lung function parameters over the four seasons were statistically significant ( F =61.72, 45.30, 47.61, 25.47, 35.13, P <0.05). The linear mixed effect model analysis showed that urinary concentrations of vanadium, manganese, iron, cobalt, nickel and antimony were negatively correlated with FEV1( B =0.202, 0.192, 0.181, 0.154, 0.131 , 0.283); urinary concentrations of aluminum, vanadium, manganese, iron, cobalt, nickel, zinc, cadmium, and antimony were negatively correlated with FVC ( B =0.252, 0.290, 0.292, 0.271, 0.201, 0.180, 0.171, 0.163, 0.381); urinary concentrations of manganese and antimony were negatively correlated with PEF ( B =0.291, 0.354)( P <0.05). Conclusion The increase of multiple metal concentrations among college students was related to lung function decline, the long term metal exposure might lead to lung function damage. So environmental metal pollution should be controlled.

A 46-year-old male patient developed scatterred reddish-brown plaques and nodules on the back 6 years prior to the presentation. Then, the lesions gradually spread to the axillary fossa and protothorax, and became indurated with slight itching in winter. Laboratory examination revealed hypergammaglobulinemia. Computed tomography(CT)scan showed multiple nodular or patchy shadows in both lungs, lymphadenectasis in axillary, mediastinal and inguinal regions, and spleen enlargement. Histopathological examination of skin lesions showed granulomatous infiltrates with plenty of lymphocytes, histiocytes and mature plasma cells in the middle and lower dermis with the presence of lymphoid follicle-like structures, but no cell atypia was observed. Immunohistochemical study showed positive staining for CD38, CD138, CD79a, κ and λ light chains. According to clinical manifestations and laboratory examination results, the patient was diagnosed with cutaneous and systemic plasmacytosis.

Objective To establish a tree shrew mode of breast tumor.Method Forty-five 3 to 4 month-old female tree shrews were orally gavaged with 20 mg 7,12-dimethylbenz(a)anthracene (DMBA) or peanut oil per animal for three times.Following that, fifteen DMBA administrated tree shrews were implanted 90 day-release medroxyprogesterone acetate ( MPA) pellets.The tree shrews were palpated once weekly to detect mammary tumors for 45 weeks after first DMBA administration.Results DMBA were able to induce breast tumors (12.5%) in tree shrews, and MPA increased the tumor incidence (50%) while no breast tumors were observed in the control group.Three induced breast tumors were intraductal papillary carcinomas and one was IDC by H&E stain.Conclusion All induced tumors are similar with spontaneous tumors in structure and molecular markers.

BACKGROUND:Short-segment pedicle screw technology has been extensively used in the treatment and repair of thoracolumbar burst fractures. The technique of operative treatment through the paraspinal muscle approach has advantages such as less trauma and bleeding, and rapid recovery. However, it requires further investigations to verify the superiority of the paraspinal muscle approach of two lateral incisions near the posterior median line. OBJECTIVE:To evaluate the clinical efficacy and Cobb’s angle of short-segment pedicle screw fixation through paraspinal muscle approach of two lateral incisions near the posterior median line in the treatment of thoracic and lumbar fractures. METHODS:From September 2010 to June 2012, 56 patients with thoracic and lumbar fractures were included in the retrospective study, including 42 males and14 females, with an average of 45 years (range 18-59 years). According to the surgical approach, patients were divided into two groups, traditional approach (n=25) and paraspinal muscle approach (n=31). The operative time, intraoperative blood loss, postoperative drainage and postoperative ambulant time in the two groups were observed and compared. The visual analog scale scores at 7 days, 1 month and 6 months postoperatively were recorded. The Cobb’s angles of suffered vertebra were measured preoperatively and at 7 days and 6 months postoperatively. RESULTS AND CONCLUSION:Al patients were fol owed up after internal fixation. The paraspinal muscle approach was superior to traditional approach in the operation time, intraoperative blood loss, postoperative drainage and postoperative ambulant time, and visual analog scale scores at 7 days and 1 month postoperatively (P<0.05). There was no significant difference between the preoperative and postoperative Cobb’s angle in the two groups (P>0.05). The short-segment pedicle screw fixation through paraspinal muscle approach of two lateral incisions near the posterior median line in the treatment of thoracic and lumbar fractures, is an effective and minimal y invasive treatment, with less trauma, less bleeding, rapid recovery, and simple operations. Similar to open surgery, this treatment can recover the anatomical morphology and reconstruct spinal stability, and had good biocompatibility to the host.

Objective To compare the clinical effects in patients treated with anterograde reamed intramedullary nail (IMN) and dynamic compression plate (DCP) for diaphyseal fractures of the humerus.Methods Forty-seven patients with diaphyseal fractures of the humerus,were divided into two groups by random digits table:IMN group (23 cases) and DCP group (24 cases),IMN and DCP were performed fixation,respectively.After the surgery,perioperative,functional outcomes of shoulder and elbow,postoperative complications between two groups were compared.Results The average follow-up time was (22.3 ± 5.7)months,3 cases were lost in 12-month-follow-up,1 case in IMN group and 2 cases in DCP group.The operation time,intraoperative blood loss in IMN group were significantly shorter than those in DCP group [(67.7 ± 15.3) min vs.(87.0 ± 12.5) min,(106.3 ±57.6) ml vs.(226.7 ±60.2) ml,P＜0.05].The incidence rate of subacromial impingement in IMN group was significantly higher than that in DCP group [18.2％ (4/22) vs.0,P ＜ 0.05].The incidence rate of wound infection in IMN group was significantly better than that in DCP group [4.5％(1/22) vs.22.7％(5/22),P ＜ 0.05].There were no statistically significant differences between two groups in other indexes (P ＞ 0.05).Conclusions DCP has some advantage in perioperative period,but they are comparable in the functional outcomes of shoulder and elbow and complications.

BACKGROUND: Super-resolution reconstruction has been extensively studied and used in many fields,such as medical diagnostics,military surveillance,frame freeze in video,and remote sensing.OBJECTIVE: In order to obtain high-resolution magnetic resonance images,gradient magnetic field is required and the signal-to-noise will be reduced due to the decrease in voxel size with traditional scan.The present study used a self-adaptive regularized super-resolution reconstruction algorithm to acquire high-resolution magnetic resonance images from four half-pixel-shifted low resolution images.METHODS: The least squares algorithm was used as a cost function.The dedvative of the cost function was calculated to obtain an iterative formula of super-resolution reconstruction.In the process of iterative process,the parameter and step size of image resolution were regularized.RESULTS AND CONCLUSION: The new regularization parameter makes cost function of the new algorithm convex within the definition region.The piori information is involved in the regularization parameter that can improve the high-frequency components of the restored image.As shown from the results obtained in the phantom imaging,the proposed super-resolution technique can improve the resolution of magnetic resonance image.

In the present research, two Chinese rhesus monkeys were inoculated intravenously with 5000 TCID50 of SIVmac239. The changes in the numbers of CD4+T lymphocyte in peripheral blood,plasma viral loads, proviral DNA and humoral antibodies against virus were periodically monitored during 121 days. At the early stage of infection, proviral DNA had been detected in PBMCs, and infectious SIVmac239 virus had been isolated from PBMCs. At the same period, the numbers of CD4+T lymphocytes were significantly decreased, and maintained at low level during the 121-day period of infection. Plasma viral loads reached the peak at week 2 post-inoculation and kept at a steady state subsequently. Moreover, antibodies against viral proteins were detected from plasma. All the results showed that the two Chinese rhesus monkeys had been infected with SIVmac239 successfully. This animal model can be applied for further AIDS researches.

AIM: To investigate the role of nuclear factor ?B (NF-?B) in the induction of IL-8 gene by TNF-? in colon cancer cells and the effect of antioxidant on the induction of IL-8. METHODS: ELISA was used to detect the concentrations of IL-8. IL-8 mRNA was analyzed by using RT-PCR. NF-?B in the cell nuclei was detected with electrophoretic mobility shift assay. RESULTS: (1) IL-8 production and IL-8 mRNA expression induced by TNF-? was blocked by pyrrolidine dithiocarbamate (PDTC). (2) TNF-? triggered the activation and translocation of NF-?B and PDTC inhibited the activation of NF-?B induced by TNF-?. CONCLUSION: The induction of IL-8 gene and protein by TNF-? is dependent on the activation of NF-?B. Antioxidants may inhibit the induction of IL-8 gene and protein through inhibiting NF-?B activation.