The host protein SAMHD1 has been identified as the first mammalian deoxynucleoside triphosphate triphosphohydrolase (dNTPase), which blocks the infection of HIV-1 in non-cycling immune cells.SAMHD1 protein is highly expressed in human myeloid-lineage cells and resting CD4+T lymphocytes, which restricts HIV-1 replication by hydrolyzing the cellular dNTPs, thus inhibiting reverse transcription and viral complementary DNA ( cDNA) synthesis. Recent studies have revealed that SAMHD 1 plays an important role in virus whole life by promoting HIV -1 genome recombination, degenerating viral genome RNA and restricting virus transmission between cells .In this review, these progress on SAMHD1 research are summarized and the mechanisms by which SAMHD 1 mediates retroviral restriction are analyzed .

According to the sequence of SmLEA gene,a DNA fragment of 1 038 bp upstream of the coding sequence of SmLEA gene was amplified by DNA walking with the genomic DNA of Salvia miltiorrhiz as the template.Sequence analysis showed that the fragment contained some putative cis-elements relating to abiotic stress,ABA,seed specific expression.So the S.miltiorrhiz seedings was treated with 100?mol/L ABA,200mmol/L NaCl,4℃,and subjected to dehydration.The real-time PCR showed that expression levels of SmLEA was increased obviously,which was in accordance with the sequence analysis.

Objective To evaluate the changes in refractive state in high-myopic patients with rhegmatogenous retinal detachment after vitrectomy combined with cataract surgery.Methods Clinical data of 30 patients of rhegmatogenous retinal detachment in the Affiliated Hospital of Qingdao University from January 2016 to March 2017 was retrospectively analyzed,and these patients were randomly dividedly into two groups:high myopia (15 patients of 15 eyes) and non high myopia group (15 patients of 15 eyes),in which patients firstly underwent vitrectomy combined with phacoemulsification and silicone oil tamponade,followed by intraocular lens (IOL) implantation after the removal of silicone oil 3 months later.The two groups were continuously followedup for 6 months after IOL implantation.Before vitrectomy,the axial length,corneal curvature were measured for calculating the predictive spherical equivalent (SE).Then axial length and corneal curvature at 1 month,3,6 months after IOL implantation were measured for calculating the actual SE.The best corrected visual acuity (BCVA) was recorded before and after operation and the LogMAR was calculated in each groups.The SE,axial length,corneal curvature before vitrectomy and 1 month,3,6 months after IOL implantation were respectively compared in each group.The relationship between the refractive prediction errors and the preoperative axial length in the high myopia group was evaluated.Results The LogMAR visual acuity was improved in both groups,and the difference between before and after treatment was statistically significant (both P ＜0.05).The SE at 1 month,3,6 months after surgery showed significantly myopic shift in the high myopic eyes,and the myopic shift gradually increased with time,with statistically significant at each time point (all P ＜ 0.05),but there was no significant difference in myopic shift between before and after surgery as well as among each time point after surgery in the non-high myopic eyes (P ＞ 0.05).Axial length and corneal curvature at 1 month,3,6 month after surgery in the high myopia group were significantly increased (all P ＜ 0.05),whereas those in the non high myopia group did not change significantly (all P ＞ 0.05).By simple linear regression analysis,the refractive prediction errors had a negative correlation with the preoperative axial length in the high myopia group (R2 =0.580,P =0.001).Conclusion The LogMAR visual acuity after vitrectomy combined with cataract surgery is improved in patients with rhegmatogenous retinal detachment.Postoperative axial length growth and corneal curvature increase are presented in patients with high myopia,and the longer the preoperative axial length is,the more myopic shift the eye shows.

OBJECTIVETo investigate the association between blood pressure and related cognitive function with Mini-Mental State Examination (MMSE) in the elderly community residents in Beijing.

METHODSA selected sample of 60 years old and over from the communities was randomized ascertained to a longitudinal study in Beijing. The baseline data was produced in 1993, in which blood pressure, MMSE and a multidisciplinary questionnaire were involved. 4 years later in 1997, a similar procedure was repeated in 2079 elderly people whose MMSE scores were normal during the baseline study.

RESULTSThe mean systolic blood pressure, diastolic blood pressure and MMSE score were 141.77 +/- 24.94 mm Hg, 81.76 +/- 12.08 mm Hg and 25.65 +/- 3.59 in baseline. The MMSE score was 23.24 +/- 5.63 in the follow-up study. Significant decline in cognition was defined as a decrease of 4 score and over during the 4-years study. The proportion of significant decline in cognition in the follow-up was larger when the systolic blood pressure or diastolic blood pressure having an increase in baseline data. Further stratified observation showed that factors as elderly with elevated blood pressure, under 75 years old from rural areas without diabetes mellitus or antihypertensive medication were more commonly seen in the ones with significant cognition decline. Increased incidence of cognitive decline was found in those with increased level of hypertension. This association was also seen in systolic blood pressure after adjustment of heart disease and cerebrovascular disease.

CONCLUSIONSIn the 4-year longitudinal study, cognitive dysfunction might cause elevated baseline systolic and diastolic blood pressure in the elderly people whose baseline MMSE scores were normal.

Aged ; Blood Pressure ; China ; epidemiology ; Cognition Disorders ; epidemiology ; etiology ; Female ; Humans ; Hypertension ; complications ; epidemiology ; Incidence ; Longitudinal Studies ; Male ; Middle Aged ; Residence Characteristics

Objective To explore the epidemical pattern of acute schistosomiasis in Poyang Lake area so as to provide the scientific evidence for control-strategy-making. Methods The data of acute schistosomiasis in 12 counties along Poyang Lake from 1960 to 2007, including the data of 2 special investigations from 1982 to 1984 and from 1987 to 1989 were collected and analyzed with the retrospective investigation methods. Results There were 29 864 cases of acute schistosomiasis in 12 counties of Poyang Lake area from 1960 to 2007, accounting for 85.5% of the total acute schistosomiasis cases of Jiangxi Province. The largest number of cases existed in Yugan County, accounting for 18. 7%. The peak of acute schistosomiasis prevalence was in 1987 with 2 088 cases. However, the case of acute schistosomiasis declined significantly, keeping at a low level, since 1990. During the 2 special investigations, the people whose age were lower than 30 years old, were the susceptible populations of acute schistosomiasis (86. 1% and 82. 9% , respectively) , most of them were peasants and students, and the infection rates were 57. 4% and 21.2%, 61.7% and 21. 8%, respectively. Fishing and swimming were the main infection ways, with the infection rates of 43.0% and 44.9% , respectively. The peak season of infection was from April to October. Conclusions The river bank and continent of Poyang Lake are the main infection areas, the spring and autumn are the main epidemic seasons and the susceptible populations are the peasants, fishmen and young students. It is very important to enhance the comprehensive prevention and treatment measures in the key areas and population for schistosomiasis control.

Objective To investigate the effect of cell death by HIV-1 infection on gene 90K/Mac-2BP by RNA interference (RNAi) in U937 cell line.Methods We used human monocyte-macrophage cell line U937 as the cell model.Cells were infected by HIV-1 ( R5-tropic) 5 days, and then stained by PE-Annexin V and PerCP-7-AAD.90K/Mac-2BP in U937 cell line was knocked down , and these cells were infected by HIV-1 for 5 days.Then, cells were stained by PE-AnnexinV and PerCP-7-AAD.Apoptosis were examined upon flow cytometry .Results The percentages of Annexin V+cells without 90K/Mac-2BP knock-down were (16.27 ±0.30)% by HIV-1 infection.The percentages of them with 90K/Mac-2BP knock-down were (31.26 ±0.35)%, (25.76 ±0.30)%, (23.69 ±0.33)% respectively.The increase of cell apoptosis rate for HIV-1-infected U937 cells by 90K/Mac-2BP siRNA transfection was significantly greater than that for HIV-1-infected untreated cells (P﹤0.01).Conclusion The apoptosis of HIV-1-infected U937 cells was regulated by the expression of 90K/Mac-2BP.

Objective To study the effects of dammarane sapogenins ( DS-1226 ) on sleep interruption-induced learning and memory impairment in mice.Methods 130 SPF healthy 5 -6-week old male ICR mice were randomly divided into control, model, DS-1226 low dose, DS-1226 medium dose and DS-1226 high dose groups.The behavioral alterations in open field (OF), Morris water maze (MWM) and step-through (ST) tests were detected at 15 days after rotating drum-induced sleep interruption ( SI) .Results The total distance, movement speed, total duration of movement were increased in OF test ( P<0.05, vs.the model group) after treatment.The latency of place navigation was increased from day 5 in the MWM test after 15 d sleep interruption, and the number of crossing in the target quadrant and the percent distance in target quadrant were decreased after 15 d sleep interruption ( P <0.05, vs.the control group), while the latency of place navigation was decreased, and the percent distance in target quadrant and percent time in target quadrant after high dose DS-1226 oral administration ( P<0.05, vs.the model group) were increased.Error times, distance in dark chamber, time in dark chamber and immobility time in dark chamber were increased in training of step through test ( P<0.05, vs.the control group);while these indexes were decreased after DS-1226 oral administration ( P<0.05, vs.the model group) .But there was no significant difference in the step through testing course.Conclusions The results show that orally administrated DS-1226 can ameliorate SI-induced learning and memory impairment, and there is a significant dosage-effect relationship.

Objective To study the mutations of Env sequence of SIVmac239 after infection of Chinese rhesus monkeys, and compare the differences and characteristics of Gp120 sequences of enterotropic and neurotropic SIV strains. Methods Six strains of simian immunodeficiency virus were analyzed in this study: four separated from peripheral blood mononuclear cells of SIVmac239-infected monkeys and two neurotropic SIVmac251 strains.Isolated and cultured monoclonal virus was obtained by limiting dilution assay.Gp120 sequences were amplified after the RNA extraction and phylogenetic analysis was processed thereafter.So did the Gp120 amino acid sequence and N-glycosylation sites analysis of the enterotropic and neurotropic strains.Results SIVmac239 had different mutations in four rhesus monkeys.The diversity in amino acid sequences of the enterotropic and neurotropic strains concentrated in the V1 and V4 regions of Gp120.The enterotropic strains had an addition of glycosylation site in V4 but the glycosylation site changes of neurotropic strains were located in the conservative regions of C1, C2 and C3.Conclusions The addition of one glycosylation site in V4 region of GP120 and loss of one glycosylation site in C1 region are associated with enhanced enterotropism and neurotropism.The differences between the enterotropic and neurotropic strains are not dipicted in Gp120 V3 region which is closely related with the tropism of strains.

Objective To study the effect of repeated rectal exposure of low -dose simian immunodeficiency virus on the systemic cellular immunity in monkeys .Methods Eight 3-to 4-year old rhesus macaques ( Macaca mulatta) (male:female 1:1) were used in this study.The monkeys were inoculated with 10 TCID50 SIVmac239 virus through rectum twice a week for consecutive 6 weeks to establish a multiple rectal exposure model of SIVmac 239 virus infection.Then, plasma viral load, CD4+ T cell count, T cell subsets and IFN-γsecretion of the experiment monkeys were determined . Results Low-dose SIVmac239 virus induced some changes in the immune system through the rectal mucosa , but didn’t induce typical infection.Repeated rectal mucosal low-dose virus exposure can activate the cellular immune system . Conclusions This study defines the effect of repeated low -dose simian immunodeficiency virus exposure on the systemic cellular immunity, and provided basic information for HIV-1 vaccine research.

Objective To investigate the carbapenem-resistant mechanism of one strain of Klebsiella pneumoniae( KPN) and one strain of Pseudomonas aeruginosa( PAE) .Methods The identity of the isolates was confirmed by using MALDI-TOF mass spectrometry, 16S rDNA and special gene amplification .The minimum inhibitory concentrations (MICs) of the antimicrobial agents were determined by VITEK 2 Compact System .CarbaNP Antimicrobial susceptibility testing , plasmid extraction, electroporation experiment , PCR amplification, and cloning and sequencing were carried out to analyze the en-coding gene of β-lactamases.Results The types of β-lactamases of the KPN were blaKPC-2 and blaSHV, confirmed by se-quencing of the PCR products , and that of the PAE were blaKPC-2 .Only blaKPC-2 was displayed in both transformants .All of the results of CarbaNP were type A .Conclusion Both strains of KPN and PAE resisting to carbapenem produce a plasmid-mediated carbapenemase blaKPC-2 , which belongs to Bush group 2f, class A β-lactamase.The extended-spectrum β-lacta-mases gene encoding blaSHV of the KPN might be located in the chromosome or not in the plasmid carrying with blaKPC-2 .