Subjects: Biology >> Botany submitted time 2018-01-29 Cooperative journals: 《干旱区科学》
Abstract：Most ecological studies in North Africa reveal a process of continuous degradation of rangeland ecosystems as a result of overgrazing. This degradation appears across the decreasing of perennial grass diversity. Indeed, the majority of steppe ecosystems are characterized by a low density of perennial grass species at present. This study evaluated the effects of temperature and water limitation on the seed germination of Stipagrostis ciliata (Desf.) de Winter, a perennial grass species. The seeds were collected from the Bou Hedma Park, Sidi Bouzid Governorate, Central Tunisia. The thermal time and hydrothermal time models were used to describe the seed germination of S. ciliata under different water potentials and temperatures. The germination response of S. ciliata seeds in darkness was evaluated over a range of temperatures (15°C, 20°C, 25°C, 30°C and 35°C) and across a wide range of osmotic potentials (0.0, –0.2, –0.6, –1.2, –1.6 and –2.0 MPa) of the polyethylene glycol (PEG6000) solutions at each temperature level. Among the tested temperatures, 25°C was found to be the optimal temperature to the germination of S. ciliata seeds. The final germination percentage (75.2%) was obtained with distilled water. The progressive decrease of osmotic potential of the PEG6000 solutions inhibited the seed germination. However, the number of days to first germination was increased with a reduction of osmotic potential. A significant positive relationship was identified between final germination percentage of S. ciliata seeds and osmotic potential of the PEG6000 solutions, with R2 ranging from 0.5678 to 0.8761. Furthermore, a high degree of congruency between predicted and observed germination time course curves was observed. In general, S. ciliata exhibits a significant adaptation capacity for water limitation and high temperature in arid ecosystems.
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Soil Science submitted time 2018-01-29 Cooperative journals: 《干旱区科学》
Abstract：Potassium (K) is known as one of the essential nutrients for the growth of plant species. The relationship between K and clay minerals can be used to understand the K cycling, and assess the plant uptake and potential of soil K fertility. This study was conducted to analyze the K forms (soluble, exchangeable, non-exchangeable and structural) and the relationship of K forms with clay minerals of calcareous soils in Kohgiluyeh and Boyer-Ahmad Province, Southwest Iran. The climate is hotter and drier in the west and south of the province than in the east and north of the province. A total of 54 pedons were dug in the study area and 32 representative pedons were selected. The studied pedons were mostly located on calcareous deposits. The soils in the study area can be classified into 5 orders including Entisols, Inceptisols, Mollisols, Alfisols and Vertisols. The main soil clay minerals in the west and south of the study area were illite, chlorite and palygorskite, whereas they were smectite, vermiculite and illite in the north and east of the province. Due to large amount of smectite and high content of organic carbon in soil surface, the exchangeable K in surface soils was higher than that in subsurface soils. It seems that organic matter plays a more important role than smectite mineral in retaining exchangeable K in the studied soils. Non-exchangeable K exhibited close relationships with clay content, illite, vermiculite and smectite. Although the amount of illite was the same in almost all pedons, amounts of structural and non-exchangeable K were higher in humid regions than in arid and semi-arid regions. This difference may be related to the poor reservoir of K+ minerals like palygorskite and chlorite together with illite in arid and semi-arid regions. In humid areas, illite was accompanied by vermiculite and smectite as the K+ reservoir. Moreover, the mean cumulative non-exchangeable K released by CaCl2 was higher than that released by oxalic acid, which may be due to the high buffering capacity resulting from high carbonates in soils.
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Soil Science submitted time 2018-01-29 Cooperative journals: 《干旱区科学》
YANG Fan
HUANG Laiming
YANG Renmin
YANG Fei
LI Decheng
ZHAO Yuguo
YANG Jinling
LIU Feng
ZHANG Ganlin
Abstract：Knowledge of soil carbon (C) distribution and its relationship with the environment can improve our understanding of its biogeochemical cycling and help to establish sound regional models of C cycling. However, such knowledge is limited in environments with complex landscape configurations. In this study, we investigated the vertical distribution and storage of soil organic carbon (SOC) and soil inorganic carbon (SIC) in the 10 representative landscapes (alpine meadow, subalpine shrub and meadow, mountain grassland, mountain forest, typical steppe, desert steppe, Hexi Corridor oases cropland, Ruoshui River delta desert, Alxa Gobi desert, and sandy desert) with contrasting bioclimatic regimes in the Heihe River Basin, Northwest China. We also measured the 87Sr/86Sr ratio in soil carbonate to understand the sources of SIC because the ratio can be used as a proxy in calculating the contribution of pedogenic inorganic carbon (PIC) to total SIC. Our results showed that SOC contents generally decreased with increasing soil depth in all landscapes, while SIC contents exhibited more complicated variations along soil profiles in relation to pedogenic processes and parent materials at the various landscapes. There were significant differences of C stocks in the top meter among different landscapes, with SOC storage ranging from 0.82 kg C/m2 in sandy desert to 50.48 kg C/m2 in mountain forest and SIC storage ranging from 0.19 kg C/m2 in alpine meadow to 21.91 kg C/m2 in desert steppe. SIC contributed more than 75% of total C pool when SOC storage was lower than 10 kg C/m2, and the proportion of PIC to SIC was greater than 70% as calculated from Sr isotopic ratio, suggesting the critical role of PIC in the C budget of this region. The considerable variations of SOC and SIC in different landscapes were attributed to different pedogenic environments resulted from contrasting climatic regimes, parent materials and vegetation types. This study provides an evidence for a general trade-off pattern between SOC and SIC, showing the compensatory effects of environmental conditions (especially climate) on SOC and SIC formation in these landscapes. This is largely attributed to the fact that the overall decrease in temperature and increase in precipitation from arid deserts to alpine mountains simultaneously facilitate the accumulation of SOC and depletion of SIC.
Subjects: Materials Science >> Materials Chemistry submitted time 2018-01-27
Abstract： It has been generally accepted that the nacreous tablets are transformed from the amorphous calcium carbonate (ACC) nanoparticles. However, how these nanoparticles are organized and transformed in three-dimensional (3D) space has not been well elucidated. Here, for the first time, we discovered a new type of immature tablets called “dendritic tablets” in domed sheet nacre of green mussels, which exhibits a dendritic surface texture in top views. By comparing their growth morphology with that of the granular tablets, we found that the ACC nanoparticles are always self-assembled into vertical clusters and then transformed into vertical crystallites of aragonite, each of which exhibits an equilibrium shape of abiotic aragonite. Most importantly, we found that the apparent contact angle between the tablet and substrate (i.e. the interlamellar membrane (ILM)) is unusually high (990 - 1260), which indicates that the ILM is non-wetting (or partial wetting) to the ACC nanoparticles. Therefore, we concluded that the non-wettability of the ILM may have great effects on the morphogenesis of the nacreous tablets.
Peer Review Status:
Awaiting Review
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the effect of propofol on myelin basic protein (MBP) expression in oligodendrocytes of SD rats at different developmental stages. Methods This study was conducted in 3-, 7-, 14- and 21-day-old SD rats (40 in each age group). In each group, the rats were randomized equally into control group and experimental group, and in the control group, the rats received an intraperitoneal injection of 25 mg/kg medium-long-chain fat emulsion followed by injections at a half dose every 20 min for 8 h; the rats in the experimental group were given injections of propofolmedium (at the initial dose of 25 mg/ kg) in the same manner. The transcriptional levels of MBP and caspase-3 in the brain tissues were detected by qRT-PCR, and the protein expression of MBP was with Western blotting and immunehistochemistry. Results Compared with those in the control groups, the expression of MBP mRNA was significantly down-regulated while caspase-3 mRNA was up-regulated in 3-, 7- and 14-day-old rats in the experimental groups (P<0.05). The protein expression of MBP in 7- and 14-day-old rats was significantly decreased in the experimental groups compared with the control groups (P<0.05). The expression of caspase-3 mRNA or MBP protein in 21-day-old rats showed no significant difference between the two groups (P>0.05). Conclusion Propofolcandown-regulatetheexpressionofMBPatboththemRNAandproteinlevelsinSDrats,especiallyinthoseat7and 14daysofage.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To clarify the mechanism by which interleukin-22 (IL-22) promotes the proliferation of fibroblast-like synoviocytes (FLS) from patients with rheumatoid arthritis (RA). Methods FLS were isolated from the synovial tissues of patients with RAand identified by immunohistochemistry for vimentin/CD68. The cells were subcultured and incubated with different concentrations of IL-22 for 24, 48, or 72 h, and their proliferation was examined using MTT assay. After treatment of the cells with IL-22 and AG490, alone or in combination, the expressions of the total and phosphorylated proteins of STAT3, ERK1/2 and P38 were detected with Western blotting. Results IL-22 significantly increased the proliferation of FLS in a dose-dependent manner (P<0.05). The total protein of STAT3 in the cells showed no significant changes with extended time of IL-22 treatment (P=0.68), but the expression of phosphorylated STAT3 protein increased significantly (P<0.001). The total and phosphorylated proteins of ERK1/2 and P38 underwent no significant changes after IL-22 treatment (P>0.05). A combined treatment with 50 ng/mL IL-22 and 100 μmol/L AG490 resulted in a significant decrease in the proliferation of FLS as compared with IL-22 treatment alone (P<0.01). Conclusion IL-22 can dose-dependently promote the proliferation of FLS from patientswithRAbyinducingphosphorylationofSTAT3proteinbutnotthroughERK1/2orP38signalpathway.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To achieve differential diagnosis of normal and malignant gastric tissues based on discrepancies in their dielectric properties using support vector machine. Methods The dielectric properties of normal and malignant gastric tissues at the frequency ranging from 42.58 to 500 MHz were measured by coaxial probe method, and the Cole-Cole model was used to fit the measured data. Receiver-operating characteristic (ROC) curve analysis was used to evaluate the discrimination capability with respect to permittivity, conductivity, and Cole-Cole fitting parameters. Support vector machine was used for discriminating normal and malignant gastric tissues, and the discrimination accuracy was calculated using k-fold cross-validation. Results The area under the ROC curve was above 0.8 for permittivity at the 5 frequencies at the lower end of the measured frequency range. The combination of the support vector machine with the permittivity at all these 5 frequencies combined achieved the highest discrimination accuracy of 84.38% with a MATLAB runtime of 3.40 s. Conclusion The support vectormachine-assisteddiagnosisisfeasibleforhumanmalignantgastrictissuesbasedonthedielectricproperties.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective Increased cAMP response element modulator α (CREMα) in T cells plays an essential role in the pathogenesis of systemic lupus erythematosus (SLE). The aim of this study was to investigate the mechanisms that elevates CREMα expression in SLE. Methods CD4+ T cells from 5 healthy volunteers and 5 SLE patients were isolated for analysis of histone H3 lysine 27 trimethylation (H3K27me3) enrichment in different gene promoters using chromatin immunoprecipitation (ChIP) microarray. The levels of H3K27me3, H3K27 demethylases Jumonji domain containing 3 (JMJD3) and ubiquitously transcribed X (UTX), and H3K27 methyltransferase enhancer of zeste homolog 2 (EZH2) within the CREMα promoter were subsequently tested by ChIP and real-time PCR in CD4+ T cells from 30 normal controls and 30 SLE patients; CREMα mRNA level was also determined by real-time RT-PCR. Results Analysis of ChIP microarray data identified that H3K27me3 enrichment at the CREMα promoter in CD4+ T cells from SLE patients was 0.23 times that of the normal control subjects. The results of ChIP and real-time PCR confirmed a marked decrease of H3K27me3 enrichment at the CREMα promoter in CD4+ T cells from SLE patients (P<0.001). The level of H3K27me3 at the promoter was negatively correlated with CREMα mRNAlevel in CD4+ T cells from SLE patients (P<0.001). In addition, a sharp increase was observed in JMJD3 binding at the CREMα promoter region in CD4+ T cells from SLE patients (P<0.001), and it was negatively correlated with H3K27me3 enrichment (P<0.001) and positively correlated with CREMα mRNAlevel (P<0.001). There were no significant changes in UTX (P=0.172) or EZH2 (P=0.281) binding at the CREMα promoter region in CD4+ T cells from SLE patients as compared to normal controls. Conclusion Increased JMJD3 binding down-regulates H3K27me3 enrichment at the CREMα promoter in CD4+ T cells ofSLEpatientstostimulateCREMαoverexpressionandresultinthedevelopmentofSLE.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To explore the hemodynamic changes in cynomolgus monkeys with mild carotid atherosclerotic (CAS) plaques after therapy with pushing manipulation on Qiaogong acupoint (MPQ). Methods Nine cynomolgus monkeys were equally randomized into MPQ group, mild CAS model group and blank control group. Mild CAS models were established in the monkeys in MPQ and model groups, and the monkeys in MPQ group received treatment with MPQ intervention after the modeling. The conditions of the carotid artery and the hemodynamic changes in the 3 groups were evaluated after the treatment. Results Formation of CAS plaques was detected in monkeys in both MPQ and model groups. The vascular cross-sectional area, plaque cross-sectional area and stenosis rate of the plaques in the two groups all differed significantly from those in the blank control group (P<0.05), but these parameters were similar between MPQ group and the model group (P>0.05). Compared with those in the blank control group, the hemodynamic parameters showed significant changes in MPQ and the model groups (P<0.05) but remained similar between the latter two groups (P>0.05). Conclusion CAS plaques can cause changes in hemodynamic parameters. Short-term therapy with MPQ does not affect the stability of the plaques or cause adverseeffectsonhemodynamicsincynomolgusmonkeyswithmildCASplaques.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the changes in the transcription of protein arginine methylation enzyme family genes in the dorsal root ganglia (DRG) following peripheral nerve injury in mice. Methods C57BL6 mouse models of neuropathic pain induced by peripheral nerve injury were established by bilateral L4 spinal nerve ligation (SNL). At 7 days after SNL or sham operation, the DRG tissue was collected for transcriptional analysis of 9 protein arginine methylation enzyme genes (Prmt1-3, Carm1, and Prmt5-9) using RNA-Seq to identify the differentially expressed genes in the injured DRGs. We also established mouse models of lateral L4 SNL and models of chronic constriction injury (CCI) of the sciatic nerve and tested the paw withdrawal frequency (PWF) in responseto mechanicalstimulation and paw withdrawal latency (PWL) in responseto thermal stimulation on 0, 3, 7 and 14 days after SNL or CCI; the expressions of the differentially expressed genes in the injured DRGs were verified in the two models using RT-qPCR. ResultsAmong the 9 protein arginine methylation enzyme family genes that were tissue-specifically expressed in the DRG, Prmt2 and Prmt3 showed the highest and Prmt6 showed the lowest basal expression. Compared with the sham-operated mice group, the mice receiving SNL exhibited upregulated Carm1 gene transcription (by 1.7 folds) but downregulated Prmt5, Prmt8 and Prmt9 transcription in the injured DRG (Prmt8 gene showed the most significant down-regulation by 16.3 folds). In mouse models of SNL and CCI, Carm1 gene expression increased progressively with time while Prmt8 transcription was obviously lowered on days 3, 7 and 14 after the injury; the transcription levels of Prmt1, Prmt5 and Prmt9 presented with no significant changes following the injuries. Both SNL and CCI induced mechanicalallodyniaandthermalhypersensitivitiesinthemiceshownbyincreasedPWFanddecreasedPWLondays3,7and 14 after the injuries. Conclusion Periphery nerve injury induces Carm1 upregulation and Prmt8 downregulation in the injured DRGinmice,whichshedslightonnewtargetsfortreatmentofneuropathicpain.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the effects of spleen tyrosine kinase (SYK) overexpression on proliferation and apoptosis of colorectal cancer cells and explore the possible mechanism. Methods The mRNA expressions of SYK and Fra-1 in 10 clinical specimens of colorectal cancer and 10 adjacent tissues were measured with qRT-PCR, and their protein expressions were detected with Western blotting. The recombinant plasmid pcDNA.3.1-SYK was constructed and transfected into colorectal cancer cells to induce SYK overexpression, and the cell viability and proliferation were assessed using by MTT assay and BrdU assay,respectively;caspase-3activityinthecellswasevaluatedwithacommercialkitandthecellapoptosiswasanalyzedwith Annexin-V FITC/PI assay. Results The expressions of SYK were significantly decreased in colorectal cancer tissues and colorectal cancer cell lines. Transfection of pcDNA.3.1-SYK into the colorectal cancer cells induced obviously upregulated mRNA and protein expressions of SYK, which caused a significant suppression of the cell viability and proliferation and enhancement of the cell apoptosis along with a significant inhibition of Fra-1 expression. Conclusions SYK overexpression inhibits the proliferation and promotes apoptosis of colorectal cancer cells, and these effects are possibly mediated by the regulationofFra-1expressionbySYK.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective We purpose a novel factor analysis method based on kinetic cluster and α-divergence measure for extracting the blood input function and the time-activity curve of the regional tissue from dynamic myocardial positron emission computed tomography(PET) images. Methods Dynamic PET images were decomposed into initial factors and factor images by minimizing the α-divergence between the factor model and actual image data. The kinetic clustering as a priori constraint was then incorporated into the model to solve the nonuniqueness problem, and the tissue time-activity curves and the tissue space distributions with physiological significance were generated. Results The model was applied to the 82RbPET myocardial perfusion simulation data and compared with the traditional model-based least squares measure and the minimal spatial overlap constraint. The experimental results showed that the proposed model performed better than the traditional model in terms of both accuracy and sensitivity. Conclusion This method can select the optimal measure by α value, and incorporate the prior information of the kinetic clustering of PET image pixels to obtain the accurate time-activity curves of the tissue,whichhasshowngoodperformanceinvisualevaluationandquantitativeevaluation.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To evaluate the diagnostic efficacy of real-time polymerase chain reaction (q-PCR) for Clostridium difficile infection (CDI) in comparison with routine culture and enzyme-linked fluorescent spectroscopy-based aprroaches. Methods Stool samples were collected from suspected CDI cases in General Hospital of Guangzhou Military Command of PLAbetween May and December in 2016. All the samples were examined with 3 methods, namely enzyme-linked fluorescent spectroscopy for detecting Clostridium difficile toxinA/B (CDAB), detection of glutamate dehydrogenase (GDH), and q-PCRfor amplification ofClostridiumdifficile-specificgenetpiandtoxingene(tcdA/tcdB),withtheresultsoffecalcultureasthereferenceforevaluating the diagnostic efficacy of the 3 methods. Results Of the total of 70 fecal samples, 13 (18.57%) were found to be positive for Clostridium difficile, including toxin-producing strains in 6 (8.57%) samples. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic coincidence rate of q-PCR for tpi were 92.31%, 91.23%, 70.59%, 98.11% and 91.43%, respectively,whichweresignificantlyhigherthanthoseofGDHtest(84.62%,84.21%,55.00%,96.00%,and84.29%,respectively; χ2=24.881, P<0.001). The sensitivity of q-PCR for tcdA/cdB was significantly higher than that of enzyme-linked fluorescent spectroscopy for CDAB in detecting CDI (66.67% vs 33.33%; χ2=35.918, P<0.001). Conclusion Both CDAB detection and q-PCR have a high specificity in detecting CDI, but GDH detection has a good sensitivity, and all these 3 methods have a high negative predictive value. Compared with other detection methods, amplification of tpi and tcdA/tcdB using q-PCR allows morerapid,sensitiveandspecificdetectionofCDI.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To observe the effect of different time windows and interventions on skin pressure ulcers and ischemiareperfusion (I/R) injury in rats. Methods Sixty-eight SD rats were randomly divided into blank control group (n=4) and model group (n=64). The rats in the model group were randomly divided into group A(n=32) without intervention and group B (n= 32) with post-conditioning. The degree of skin compression, neutrophil infiltration and serum levels of free radicals were observed in the rats after compression for 2, 4, 6, and 8 h (8 rats at each time point). ResultsAsignificant difference was found in the severity of skin damage among the control group, groupA, and group B (P=0.001), and the injury was milder in group B thaningroupA.Severeskinlesionsoccurredin2ratsafterskincompressionfor6h,ascomparedwith6aftercompressionfor 8 h (P=0.043), but in none of the rats after compression for 2 or 4. Seventeen rats in group B and 15 in groupAshowed grade 1 neutrophil infiltration in the skin lesions, and 8 rats in group B and 10 in group Ashowed grade II neutrophil infiltration (P= 0.002). Neutrophil infiltration was the mildest in rats with a 2-h compression, and exacerbated progressively and significantly as the compression time extended (P=0.027). With the prolongation of the intervention time, the rats in both groups A and B showed decreased SOD and increased MDA and NO levels, and overall the I/R injury was milder in 2- and 4-h compression groups than in 6- and 8-h compression groups. The level of serum SOD was significantly higher and MDAand NO levels were significantly higher in group B than in groupA(P<0.05). Conclusion Ischemic post-conditioning can relieve I/Rinjury in acute pressure ulcer in rats. The effective time window for intervention is within 6 h of ischemia, and the effect of ischemic postconditioning is optimal within 2 h. Ischemic post-conditioning can alleviate free radical injury and inflammation caused by I/R injury.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To construct a cell model of 4.1Rgene knockout in murine macrophage cell line RAW264.7 using CRISPR/ Cas9 technique. Methods Three high-grade small-guide RNAs (sgRNAs) that could specifically identify 4.1R gene were synthesized and inserted into lentiCRISPRv2 plasmid. RAW264.7 cells were infected with sgRNA-Cas9 lentivirus from 293T cells transfected with the recombinant sgRNA-lentiCRISPRv2 plasmid, and the positive cells were screened using puromycin and the monoclonal cells were obtained. The expression of 4.1R protein in the monoclonal cells was measured by Western blotting, and the mutation site was confirmed by sequence analysis. Result A 4.1R gene knockout RAW264.7 cell line was obtained, which showed a 19-bp deletion mutation in the 4.1R gene sequence and obviously enhanced proliferation. Conclusion We successfully constructed a 4.1Rgene knockout macrophage cell line using CRISPR/Cas9 technique, which may facilitatefurtherinvestigationofthefunctionof4.1Rinmacrophages.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To study the effects of low-intensity pulsed ultrasound (LIPUS) in promoting repair of cyclophosphamide (CTX)-induced ovarian injury in female rats. Methods Fifty female SD rats were subjected to intraperitoneal injection of cyclophosphamide at 30 mg/kg for 5 consecutive days to induce premature ovarian failure. Successful modeling was achieved in 43 rats, which were then randomized into model group (21 rats) and treatment group (22 rats), with another 13 rats without any injections serving as the normal control group. The rats in the treatment group received low-intensity pulsed ultrasound treatment, and those in the other two groups received no interventions. The estrous cycle of the rats was monitored during the experiment, and all the rats were sacrificed 7 days after the treatment for analysis of serum estradiol (E2), follicle stimulating hormone (FSH), anti-Mullerian hormone (AMH), morphological changes of the ovary and the number of follicles. Results Compared with those in the normal control group, the rats in the model group showed disorders in the estrous cycle, reduced number of follicles at all levels, significantly decreased serum E2 andAMH, and increased serum FSH following CTX injection (P=0.01). Ultrasound treatment obviously promoted the recovery of estrous cycle, significantly increased the number of follicles and serum E2 (P=0.01), and decreased FSH (P=0.01) in the rats with CTX-induced ovarian injury, butAMH showed no significant changes after ultrasound treatment (P=0.50). Conclusion Low-intensity pulsed ultrasound can promote the repair oftheCTX-inducedovarianinjuryinSDrats.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To obtain high-quality low-dose CT images using total generalized variation regularization based on the projection data for low-dose CT reconstruction. Methods The projection data of the CT images were transformed from Poisson distribution to Gaussian distribution using the linear Anscombe transform. The transformed data were then restored by an efficient total generalized variation minimization algorithm. Reconstruction was finally achieved by inverse Anscombe transform and filtered back projection (FBP) method. Results The image quality of low-dose CT was greatly improved by the proposed algorithm in both Clock and Shepp-Logan phantoms. The signal-to-noise ratios (SNRs) of the Clock and SheppLogan images reconstructed by FBPalgorithm were 17.752 dB and 19.379 dB, which were increased by the proposed algorithm to 24.0352 and 23.4181 dB, respectively. The NMSE of the Clock and Shepp-Logan images reconstructed by FBP algorithm was 0.86% and 0.58%, which was reduced by the proposed algorithm to 0.2% and 0.23%, respectively. Conclusion The proposed method can effectively suppress noise and strip artifacts in low-dose CT images when piecewise constant assumption is not possible.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To construct a lentiviral vector for delivering short hairpin RNA(shRNA) targeting PAX6 and investigate its effect on the proliferation of glioma U251 cells in vitro. Methods Two small interfering RNAsequences targeting PAX6 gene were designed based on the reported sequence of PAX6 and annealed to form a double-stranded chain, which was inserted into a lentiviral vector to construct the recombinant lentiviral vector shRNA-PAX6. The recombinant vector was infected into U251 cells, and the expression of PAX6 mRNA and protein in the cells was detected by real-time PCR and Western blotting, respectively. The changes in the proliferation of U251 cells after the infection was assessed using MTT assay. Results Double enzyme digestion of the lentiviral vector pLKD-CMV-G&NR-U6-shRNA yielded an 8208-bp fragment, and colony PCR and sequencing analysis confirmed successful construction of the lentiviral vector shRNA-PAX6. Infection of the cells with shRNA-PAX6 caused a significant reduction of the expressions of PAX6 mRNAand protein (P<0.05) and resulted in obviously increased proliferation of U251 cells (P<0.05). Conclusion We successfully constructed the recombinant vector shRNA-PAX6 forsilencingPAX6gene.PAX6genesilencingresultsinincreasedproliferationofU251cellsinvitro.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To compare the safe duration of apnea and intubation time between face mask ventilation with air and 100% oxygen during induction of general anesthesia. Methods Eighty adult patients with ASA class I or II without predicted difficult airways were scheduled for elective surgery under general anesthesia. The patients were randomized to receive anesthesia induction with preoxygenation [Group 1, n=40, fraction of inspired oxygen (FiO2)=1] or without preoxygenation (Group2, n=40, FiO2=0.21). Two experienced anesthesiologists performed the mask ventilation and tracheal intubation during induction, and the assistants adjusted the oxygen concentration and recorded the pulse oxygen saturation (SpO2) and other variables. The cases where SpO2 decreased to below 90% before accomplishment of intubation were considered unsuccessful, and mask ventilation with 100% oxygen was given.After tracheal intubation, mechanical ventilation was not initiated until the SpO2 decreased to 90%. The number of unsuccessful cases, the safe duration of apnea and intubation time were recorded in the two groups. Results There was no unsuccessful case in either groups. The safe duration of apnea was 469.5±143.0 s in Group 1 and 63.6±20.0 s in Group 2, and the intubation time was 34.4±12.6 s and 32.8±9.6 s, respectively. The safe duration of apnea was significantly longer than the intubation time in both groups (P<0.01). The intubation time and the number of cases with SpO2≥ 90% before completion of tracheal intubation were similar between the two groups. The safe duration of apnea was significantly shorter in Group 2 than in Group 1 (P<0.01) and was correlated with the body mass index of the patients (P<0.05). Conclusion Anesthesia induction without preoxygenation can provide sufficient time for experienced anesthesiologists to completetrachealintubation.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To study the protective effect of dexmedetomidine against perioperative inflammation and on pulmonary function in patients undergoing radical resection of lung cancer. Methods From May, 2014 to May, 2016, 124 patients with lung cancer receiving radical surgeries were randomized into experimental group (n=62) and control group (n=62). The patients in the control group received a single anesthetic agent for anesthesia, and additional dexmedetomidine was given in the experimentalgroup.Thelevelsofseruminterleukin-1β(IL-1β),IL-10,andtumornecrosisfactor-alpha(TNF-α)weremeasured before the operation (T0), at 30 min (T1) and 60 min (T2) during one lung ventilation (OLV) and at the end of operation (T3). Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of malondialdehyde (MDA), myeloperoxidase (MPO) and xanthine oxidase (XOD), and the arterial oxygen partial pressure (PaO2), oxygenation index (OI), airway plateau pressure (APP) and airway resistance (AR) were also recorded. Results At the time points of T1 and T2, IL-1β, IL-10, MDA, MPO, TNF-α, and XOD levels were significantly increased in both of the groups, but the levels of IL-1, IL-10, TNF-α and MDA weresignificantlylowerandMPOandXODlevelssignificantlyhigherintheexperimentalgroupthaninthecontrolgroup(P< 0.05). In both groups, PaO2 and OI decreased and APP and AR increased significantly at T1 and T2, but APP and AR were significantly lower and PaO2 and OI significantly higher in the experimental group than in the control group (P<0.05). Conclusion Anesthesia with dexmedetomidine in lung cancer patients undergoing radical surgery can effectively reduce the inflammatoryresponseofthelungsandprotectthelungfunctionofthepatients.
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