Objective To explore the feasibility of mouse muscle-derived cells with adenovirus-mediated expression of BMP-2 in the treatment of mouse tibia bone defect via collagen sponge as scaffold. Methods Mouse adenovirus BMP-2 plasmids were prepared and identified by PCR.The adherent cells of muscle-derived stem cells cultured in vitro were passaged,cells of the third generation were selected,and recombinant Ad-BMP-2 plasmids were expressed and incubated in mouse myoblasts.The number of BMP-2 positive cells was measured using indirect immunofluorescence method,and alkaline phosphatase(ALP) method was adopted to determine the cell activity in each group.The mouse models of proximal tibial bone defect were established(n=80) and were divided into Ad-BMP-2 transfection group,Ad-LacZ transfection group,blank group and Ad-BMP-2 implantation group.The histological and radiological changes were observed 3 weeks after operation. Results It was revealed by indirect immunofluorescence that BMP-2 positive cells were frequently found in Ad-BMP-2 transfection group,while none were observed in Ad-LacZ transfection group and blank group.The ALP activity was higher in Ad-BMP-2 transfection group,while that was extremely low in Ad-LacZ transfection group and blank group.There was most typical imaging of repair and healing of bone defect in Ad-BMP-2 transfection group,followed by Ad-BMP-2 implantation group,while there was no typical imaging in Ad-LacZ transfection group and blank group. Conclusion The constructed Ad-BMP-2 plasmids can effectively transfect mouse muscle-derived cells,and the transfected cells can continuously express effective amount of BMP-2.The mouse muscle-derived cells with adenovirus-mediated expression of BMP-2 play a definite role in the treatment of bone defect,which provides an effective method and material for clinical application.

BACKGROUND:The mechanism of differentiation and proliferation of bone marrow-derived mesenchymal stem cells remains unclear. In addition, issues such as how signal pathways such as Ca2+and bone marrow-derived mesenchymal stem cellproliferation and differentiation signals form complex signal network remain poorly understood.
OBJECTIVE:To investigate the effect of Ca2+in the induced differentiation of bone marrow-derived mesenchymal stem cells into hepatocytes.
METHODS:Bone marrow-derived mesenchymal stem cells were isolated from rat bone marrow using whone bone marrow adherence method, purified, amplified, and induced with hepatocyte growth factor. [Ca2+]i in the directional differentiated bone marrow-derived mesenchymal stem cells and control bone marrow-derived mesenchymal stem cells were detected with flow cytometry. Bone marrow-derived mesenchymal stem cells induced with hepatocyte growth factor were mixed with nimodipine of different concentration, and cells were divided into three groups:hepatocyte growth factor+nimodipine 10 mg/L, 50 or 100 mg/L groups. cellgrowth was observed with inverted phase contrast microscope and alpha 1-antitrypsin expression of the cells was confirmed by immunocytochemistry. The calcineurin M and the activation of extracellular signal regulated kinase pathway was detected by reverse transcription-PCR and western blotting, respectively.
RESULTS AND CONCLUSION:[Ca2+]i in the directional differentiated bone marrow-derived mesenchymal stem cells was higher than in the control group (P<0.05). After addition of a larger dose of nimodipine, no differentiation of cells was obeserved and growth of bone marrow-derived mesenchymal stem cells was getting worse. There were few alpha 1-antitrypsin positive cells in the nimodipine groups. Calcineurin Mexpression was significantly increased in directional differentiated bone marrow-derived mesenchymal stem cells and smal dose of nimodipine than the controls (P<0.05). However, no significant difference was found among middle, high dose nimodipine and control groups (P>0.05). These findings indicate that Ca2+could participate in the differentiation of bone marrow-derived mesenchymal stem cells into hepatocytes incuded with cytokines, and also maintain the survival and proliferation of bone marrow-derived mesenchymal stem cells.

At present, there is no cure for acquired immune deficiency syndrome (AIDS) due to HIV-1 latent reservoirs. Therefore, it urgently requires novel HIV-1 latency-regulating agents with high potency, low toxicity and favorable drug-like properties to achieve a functional cure for AIDS. Herein, we reviewed the advances in HIV-1 latency-regulating agents since 2019, including the drug discovery strategies, bioactivities, and mechanisms of these compounds. It is of great guiding significance in the development of latency-regulating agents with clinical value.

Objective To determine the difference in blood microcirculation recovery between normal frostbite and high-altitude frostbite during the wound healing.Methods Twenty four male rats were randomly divided into control group (n=8), normal frostbite group (n=8), and high-altitude group (n=8). The normal frostbite group rats were frozen to produce mid-degree frostbite models by controlling the freezing time with liquid nitrogen penetration equipment. The high-altitude frostbite group rats were acclimated to a hypoxic and low-pressure environment for 1 week, and then the high-altitude frostbite models were constructed by the same way with liquid nitrogen penetration apparatus. On days 3, 7, 11, 15, 19, and 23 after modeling, the recovery situation of blood circulation of each group was observed with contrast ultrasonography by injecting SonoVue micro-bubble into rats' tail. Finally, the micro-bubble concentration (MC) was calculated to confirm the blood circulation recovery with software Image Pro. ResultsAt different time points, the wound area of the high-altitude frostbite group was bigger than that of the normal frostbite group, and the MC of control group was always about (27±0.2)×109/ml. On day 3, 7, 11, 15, 19, and 23, the MC was significantly lower in the high-altitude frostbite group than in the control group and normal frostbite group (P<0.05). The MC of normal frostbite group was significantly lower than that of the control group on day 3, 7, 11, 15 and 19 (P<0.05). In addition, no obvious difference in MC was found between normal group and control group on the 23th day (P<0.05).Conclusion The blood microcirculation recovery after high-altitude frostbite is significantly slower than the normal frostbite.

Objective To evaluate the effect of the difficult embryo transfer on the clinical pregnancy outcome of in vitro fertili-zation-embryo transfer(IVF-ET) .Methods There were 209 fresh cycles of difficultly transferring and 2 489 fresh cycles of easily embryo transferring between January 2011 and December 2012 .The clinical outcome was compared .Results There were statistical-ly significant differences in the catheter blood staining rates (51 .20% vs 27 .68% ,P< 0 .05) ,implantation rate(31 .14% vs 35 . 54% ,P<0 .05) ,and clinical pregnancy rate (46 .41% vs 55 .56% ,P<0 .05)between the two groups .There was no significant difference in the rates of ectopic pregnancy and miscarriage between the two groups (P>0 .05) .Conclusion Difficulty ET will in-fluence the clinical pregnancy .Therefore ,all efforts should be made to avoid the difficult transfer in order to increase the pregnant rate .

Objective To understand the impact of Qionghai Lake wetland ecological protection construction on the preva?lence of schistosomiasis,so as to provide the evidence for formulating the strategies for schistosomiasis control and prevention. Methods A retrospective survey of the construction of Qionghai Lake wetland was performed,and eleven villages around the wetland were surveyed for schistosomiasis endemic situation. The influence of the wetland project on the schistosomiasis preva?lence and Oncomelania hupensis snail status were investigated. Results Before the construction of Qionghai Lake wetland,the snail elimination and extended chemotherapy for residents was performed. After the project was finished,the roads and ditches were hardened. From 2009 to 2014,the schistosome infection rate of residents declined from 0.37% to 0. No schistosome infect?ed snails were found and in recent 2 years,no snails were found. No mice were infected in the sentinel tests. Conclusions The construction of Qionghai Lake wetland effectively eliminates snails,and interrupts the transmission of schistosomiasis. Howev?er,the environment of the wetland is more suitable for snail breeding,and therefore,the surveillance still should be strength?ened.

Objective To evaluate the intervention effect of Yi?Han bilingual health education of schistosomiasis control. Methods Baimiao Village in Daqing Town,Xichang City,where Yi Nationality inhabited,was chosen as a pilot to carry out Yi?Han bilingual health education of schistosomiasis control from 2012 to 2015. The villagers and students in the pilot area were in?vestigated by questionnaires before and after the intervention to understand their awareness and correct behavior status on schis?tosomiasis control. Results After the intervention of Yi?Han bilingual health education of schistosomiasis control for 3 years, the awareness rate and the correct rate of behavior on schistosomiasis control of the villagers in the pilot area improved from 45.79%and 51.12%in 2012 to 97.80%and 98.78%in 2015. As for the students,the two rates mentioned above improved from 64.16%and 60.83%in 2012 to 100%and 98.89%in 2015 respectively,and all the differences between the rates before and af?ter the intervention were statistically significant( all P<0.01). Conclusion The intervention of Yi?Han bilingual health educa?tion of schistosomiasis control can obviously improve the knowledge awareness rates and the correct rates of behavior of the resi?dents and students in the gathering area of Yi Nationality.

Objective To evaluate the application value of polymerase chain reaction (PCR)-fluorescence probe method in identifying genotypes of hepatitis C virus (HCV).Methods One hundred and sixty six serum samples from patients with chronic HCV infection were collected nationwide from March to June 2016.HCV Core-E1 gene region was amplified and sequenced by nested reverse transcription-PCR (RT nested-PCR)and genetic subtypes were analyzed by phylogenetic tree,meanwhile HCV genotypes were also determined by PCR-fluorescent probe method.Kappa test was used to compare the consistency of two methods.Results Among 166 samples detected by RT nested-PCR,the genotype of 66 samples (39.8%) was 1 b,34 (20.5%)was 2a,16 (9.6%)was 3a,27 was 3b (16.2%),23 (13.9%)was 6a.Two samples with 3b genotype detected by RT nested-PCR were identified as 1 b by PCR-fluorescent probe.The consistency rate of two methods was 98.7% (164 /166),there was no significant difference between two methods (χ2 =0.0492,P >0.05).Conclusion PCR-fluorescence probe method can accurately identify HCV genotypes and can be used in clinic.

Objective To determine the effects of non-thermal biological effect of low frequency pulsed electromagnetic field (LFPEF) with 15 Hz and 30 mT on ulcer wound during the plateau stress ulcer cure.Methods Thirty male Sprague-Dawley rats were assigned to three equal groups:control,normal cure group (NC) and exposure treatment groups (ET).The plateau rats stress ulcer models were constructed with the combination method of a hypoxic and low-pressure acclimation and the stimulation of absolute ethyl alcohol irrigating stomach.The LFPEF equipment generated the LFPEF of 15 Hz,40％ duty cycle and 30 mT to expose and treat the rats' stomach of ET group with the frequency of 3 hours each day.After 6 days of exposure treatment,the stress ulcer cure situation of each group was evaluated by the methods of macroscopic observation,the gastric juice pH values detection and ulcer index (UI) measurement.Results After 6 days of model,the macroscopic observation showed that the ulcer of NC group was worse than the that of ET group (P＜0.05).The pH values and UI of ET group were significantly different with those of NC group,and closed to those of the control group.Conclusion The nonthermal biological effect of LFPEF could promote the plateau stress ulcer cure.

AIM:To observe the structural basis of ocular motility abnormalities in patients with congenital fibrosis of the extraocular muscles type Ⅰ ( CFEOM Ⅰ) due to missense mutations in the developmental kinesin KIF21A using high - resolution magnetic resonance imaging ( MRI) .
METHODS: Totally 11 affected individuals reported KIF21A mutations were correlated with MRI studies demonstrating extraocular muscles ( EOMs ) size, location, contractility, and innervation. EOMs and the motor nerve in the orbits were imaged with T1 weighted in a triplanar scan using a dual-phased coils with 2. 0mm thick. Motor nerves were imaged at the brainstem using head coils and 3D-FIESTA with 0. 6-mm thick.
RESULTS: Patients with CFEOM Ⅰ exhibited different degrees of hypoplasia of oculomotor nerve, the abducens nerve and the trochlear nerve were also affected, of which 8 cases of orbital section could see the signal of abnormal nerve dominated by oculomotor nerve to lateral rectus. The both sides of six EOMS in all patients exhibited variable atrophy and abnormal bright internal signal on T1 imaging, particularly severe for the superior rectus and levator muscles.
CONCLUSION: High - resolution MRI can directly demonstrate pathology of motor nerves,affected EOMs, and ‘Pulley' hypoplasia caused by CFEOM Ⅰ due to mutations in KIF21A,and these findings suggest that the neuronal hypoplasia is the etiological factor of CFEOM.