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1.

Objectives

To evaluate the possible photoprotection mechanisms of cyclic and linear electron flux (CEF and LEF) under specific high temperature and high light (HH) stress.

Methods

Six-leaf-stage tomato seedlings (“Liaoyuanduoli”, n=160) were divided into four parts: Part 1, served as control under 25 °C, 500 μmol/(m2·s); Part 2, spayed with distilled water (H2O) under 35 °C, 1000 μmol/(m2·s) (HH); Part 3, spayed with 100 μmol/L diuron (DCMU, CEF inhibitor) under HH; Part 4, spayed with 60 μmol/L methyl viologen (MV, LEF inhibitor) under HH. Energy conversion, photosystem I (PSI), and PSII activity, and trans-thylakoid membrane proton motive force were monitored during the treatment of 5 d and of the recovering 10 d.

Results

HH decreased photochemical reaction dissipation (P) and the maximal photochemical efficiency of PSII (F v/F m), and increased the excitation energy distribution coefficient of PSII (β); DCMU and MV aggravated the partition imbalance of the excitation energy (γ) and the photoinhibition degree. With prolonged DCMU treatment time, electron transport rate and quantum efficiency of PSI (ETRI and Y I) significantly decreased whereas acceptor and donor side limitation of PSI (Y NA and Y ND) increased. MV led to a significant decline and accession of yield of regulated and non-regulated energy Y NPQ and Y NO, respectively. Membrane integrity and ATPase activity were reduced by HH stress, and DCMU and MV enhanced inhibitory actions.

Conclusion

The protective effects of CEF and LEF were mediated to a certain degree by meliorations in energy absorption and distribution as well as by maintenance of thylakoid membrane integrity and ATPase activity.
  相似文献   

2.

目的

化学反应机理在内燃机计算流体动力学(CFD)仿真中起关键作用。基于敏感性分析与粒子群 寻优算法,本文旨在提出适用于内燃机CFD仿真的焦炉气化学反应机理,为焦炉气在内燃机上的应用研究提供条件。

创新点

1. 结合敏感性分析与离子群寻优算法,对化学反应机理参数进行了优化;2. 建立了焦炉气 化学反应机理,可准确仿真滞燃期、层流火焰速度、缸内压力变化和NOx生成。

方法

1. 根据简单碳氢燃料机理结构,搭建焦炉气化学反应机理(图1);2. 通过敏感性分析,获得在燃烧中起关键作用的化 学反应(图2和3);3. 通过粒子群寻优算法,对上述关键化学反应的动力学参数进行优化(图4和5);4. 通过数 值仿真,验证机理的准确性(图6~13、16和17)

结论

1. 根据敏感性定义,搭建的敏感性分析模型可准确地识别在燃烧过程中起关键作用的化学反应;2. 基于粒子 群寻优算法搭建的优化模型可对化学反应的动力学参数进行合理优化;3. 优化后得到的焦炉气化学反应机理可准确预测滞燃 期与层流火焰速度以及模拟内燃机缸内压力变化与NOx 生成。
  相似文献   

3.

Objective

The aim of our study is to observe the impact of cholangiocarcinoma-derived exosomes on the antitumor activities of cytokine-induced killer (CIK) cells and then demonstrate the appropriate mechanism.

Methods

Tumor-derived exosomes (TEXs), which are derived from RBE cells (human cholangiocarcinoma line), were collected by ultracentrifugation. CIK cells induced from peripheral blood were stimulated by TEXs. Fluorescence-activated cell sorting (FACS) was performed to determine the phenotypes of TEX-CIK and N-CIK (normal CIK) cells. The concentrations of tumor necrosis factor-α (TNF-α) and perforin in the culture medium supernatant were examined by using an enzyme-linked immunosorbent assay (ELISA) kit. A CCK-8 kit was used to evaluate the cytotoxic activity of the CIK cells to the RBE cell line.

Results

The concentrations of TNF-α and perforin of the group TEX-CIK were 138.61 pg/ml and 2.41 ng/ml, respectively, lower than those of the group N-CIK 194.08 pg/ml (P<0.01) and 3.39 ng/ml (P<0.05). The killing rate of the group TEX-CIK was 33.35%, lower than that of the group N-CIK (47.35% (P<0.01)). The population of CD3+, CD8+, NK (CD56+), and CD3+CD56+ cells decreased in the TEX-CIK group ((63.2±6.8)%, (2.5±1.0)%, (0.53±0.49)%, (0.45±0.42)%) compared with the N-CIK group ((90.3±7.3)%, (65.7±3.3)%, (4.2±1.2)%, (15.2±2.7)%), P<0.01.

Conclusions

Our results suggest that RBE cells-derived exosomes inhibit the antitumor activity of CIK cells by down-regulating the population of CD3+, CD8+, NK (CD56+), and CD3+CD56+ cells and the secretion of TNF-α and perforin. TEX may play an important role in cholangiocarcinoma immune escape.
  相似文献   

4.

Objective

To investigate a possible association between common variations of the P2RY12 and the residual clopidogrel on-treatment platelet reactivity after adjusting for the influence of CYP2C19 tested by thromboelastography (TEG).

Methods

One hundred and eighty patients with acute coronary syndrome (ACS) treated with clopidogrel and aspirin were included and platelet function was assessed by TEG. Five selected P2RY12 single nucleotide polymorphisms (SNPs; rs6798347, rs6787801, rs6801273, rs6785930, and rs2046934), which cover the common variations in the P2RY12 gene and its regulatory regions, and three CYP2C19 SNPs (*2,*3,*17) were genotyped and possible haplotypes were analyzed.

Results

The high on-treatment platelet reactivity (HTPR) prevalence defined by a platelet inhibition rate <30% by TEG in adenosine diphosphate (ADP)-channel was 69 (38.33%). Six common haplotypes were inferred from four of the selected P2RY12 SNPs (denoted H0 to H5) according to the linkage disequilibrium R square (except for rs2046934). Haplotype H1 showed a significantly lower incidence of HTPR than the reference haplotype (H0) in the total study population while haplotypes H1 and H2 showed significantly lower incidences of HTPR than H0 in the nonsmoker subgroup after adjusting for CYP2C19 effects and demographic characteristics. rs2046934 (T744C) did not show any significant association with HTPR.

Conclusions

The combination of common P2RY12 variations including regulatory regions rather than rs2046934 (T744C) that related to pharmacodynamics of clopidogrel in patients with ACS was independently associated with residual on-clopidogrel platelet reactivity. This is apart from the established association of the CYP2C19. This association seemed more important in the subgroup defined by smoking.
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5.

Objective

To investigate the effects of resuscitation with normal saline (NS), hypertonic saline (HTS), and hydroxyethyl starch (HES) on regulatory T cells (Tregs), helper T 1 (Th1)/Th2 and cytotoxic T 1 (Tc1)/Tc2 profiles in the treatment of hemorrhagic shock.

Methods

Rats subjected to severe hemorrhagic shock were resuscitated for 30 min with NS (n=8), HTS (n=8), or HES (n=8); sham (n=8) and naive control (n=8) groups were used for comparison. Following fluid resuscitation, the whole shed blood was reinfused for 30 min, and the rats were observed with continuous hemodynamic monitoring for 120 min. CD4+CD25+Foxp3+ Treg proportions, Th1/Th2 and Tc1/Tc2 profiles in spleen were analyzed by three-color flow cytometry.

Results

The proportion of CD4+CD25+Foxp3+ Tregs and ratios of Th1/Th2 and Tc1/Tc2 did not differ among control, sham, and HTS groups, but were significantly lower in NS and HES groups (both P<0.05 vs. sham); NS and HES levels were similar. The level of Tc1 was significantly increased in HTS (P<0.05 vs. sham), and levels of Tc2 were increased in NS, HES, and HTS groups compared to sham (all P<0.05), but did not differ from each other.

Conclusions

HTS resuscitation has a greater impact on immune system recovery than NS or HES by preserving the proportion of Tregs and maintaining the balance between Th1/Th2 and Tc1/Tc2 cells in the spleen. Thus, HTS resuscitation provides potential immunomodulatory activity in the early stage after hemorrhagic shock.
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6.
The reuse of wastewater for the irrigation of farmlands is gaining popularity, and the nutrient leaching associated with wastewater irrigation is becoming a matter of concern. The variability of nitrogen and phosphorus fractions in wastewater-irrigated soil was investigated in both horizontal and vertical directions in Kongjiaxiang, Tongliao, Inner Mongolia, China. The results showed that wastewater irrigation resulted in the concentrations of available N and P being 40.36% and 66.49% higher, respectively, than those with groundwater irrigation. Different forms of N and P exhibited significantly different distribution patterns. Higher concentrations of NO3- and total available N, as well as of those of Ca-P and total available P were observed near wastewater irrigation channels. Ca-P has a spatial distribution pattern similar to that of available P. The concentrations of NO3- and NH4+ were the highest in top soil and decreased with depth. The complex interactions between nitrate leaching and nitrogen transformation processes (e.g., nitrification, denitrification, and mineralization) determined the vertical profile of NO3- . The significant amount of NH4+ loss inhibited its deep seepage. The Ca-bound compound contained more P than other inorganic fractions as a result of high Ca levels throughout the soil profile. The differences in the concentrations of Ca-bound P at different depths could be due to the upward flux or translocation of Ca from subsurface to surface soil and the sequestration of P.  相似文献   

7.

Objective

To evaluate the potential adjuvant effect of Agrocybe aegerita lectin (AAL), which was isolated from mushroom, against a virulent H9N2 strain in vivo and in vitro.

Methods

In trial 1, 50 BALB/c male mice (8 weeks old) were divided into five groups (n=10 each group) which received a subcutaneous injection of inactivated H9N2 (control), inactivated H9N2+0.2% (w/w) alum, inactivated H9N2+0.5 mg recombinant AAL/kg body weight (BW), inactivated H9N2+1.0 mg AAL/kg BW, and inactivated H9N2+2.5 mg AAL/kg BW, respectively, four times at 7-d intervals. In trial 2, 30 BALB/c male mice (8 weeks old) were divided into three groups (n=10 each group) which received a subcutaneous injection of inactivated H9N2 (control), inactivated H9N2+2.5 mg recombinant wild-type AAL (AAL-wt)/kg BW, and inactivated H9N2+2.5 mg carbohydrate recognition domain (CRD) mutant AAL (AAL-mutR63H)/kg BW, respectively, four times at 7-d intervals. Seven days after the final immunization, serum samples were collected from each group for analysis. Hemagglutination assay, immunogold electron microscope, lectin blotting, and co-immunoprecipitation were used to study the interaction between AAL and H9N2 in vitro.

Results

IgG, IgG1, and IgG2a antibody levels were significantly increased in the sera of mice co-immunized with inactivated H9N2 and AAL when compared to mice immunized with inactivated H9N2 alone. No significant increase of the IgG antibody level was detected in the sera of the mice co-immunized with inactivated H9N2 and AAL-mutR63H. Moreover, AAL-wt, but not mutant AAL-mutR63H, adhered to the surface of H9N2 virus. The interaction between AAL and the H9N2 virus was further demonstrated to be associated with the CRD of AAL binding to the surface glycosylated proteins, hemagglutinin and neuraminidase.

Conclusions

Our findings indicated that AAL could be a safe and effective adjuvant capable of boosting humoral immunity against H9N2 viruses in mice through its interaction with the viral surface glycosylated proteins, hemagglutinin and neuraminidase.
  相似文献   

8.

Objective

In previous studies, Lactobacillus plantarum ZJ316 showed probiotic properties, such as antimicrobial activity against various pathogens and the capacity to significantly improve pig growth and pork quality. The purpose of this study was to reveal the genes potentially related to its genetic adaptation and probiotic profiles based on comparative genomic analysis.

Methods

The genome sequence of L. plantarum ZJ316 was compared with those of eight L. plantarum strains deposited in GenBank. BLASTN, Mauve, and MUMmer programs were used for genome alignment and comparison. CRISPRFinder was applied for searching the clustered regularly interspaced short palindromic repeats (CRISPRs).

Results

We identified genes that encode proteins related to genetic adaptation and probiotic profiles, including carbohydrate transport and metabolism, proteolytic enzyme systems and amino acid biosynthesis, CRISPR adaptive immunity, stress responses, bile salt resistance, ability to adhere to the host intestinal wall, exopolysaccharide (EPS) biosynthesis, and bacteriocin biosynthesis.

Conclusions

Comparative characterization of the L. plantarum ZJ316 genome provided the genetic basis for further elucidating the functional mechanisms of its probiotic properties. ZJ316 could be considered a potential probiotic candidate.
  相似文献   

9.

Objective

To investigate the protective effects of parecoxib from oxidative stress induced by hydrogen peroxide (H2O2) in rat astrocytes in vitro.

Methods

All experiments included 4 groups: (1) negative control (NC) group, without any treatment; (2) H2O2 treatment group, 100 µmol/L H2O2 treatment for 24 h; (3) and (4) parecoxib pretreatment groups, 80 and 160 µmol/L parecoxib treatment for 24 h, respectively, and then treated with 100 µmol/L H2O2. Several indices were investigated, and the expressions of Bax, Bcl-2, and brain-derived neurotrophic factor (BDNF) were quantified.

Results

Compared to the NC group, exposure to H2O2 resulted in significant morphological changes, which could be reversed by pretreatment of parecoxib. In addition, H2O2 treatment led to loss of viability (P=0.026) and increased intracellular reactive oxygen species (ROS) levels (P<0.001), and induced apoptosis (P<0.01) in the primary astrocytes relative to the NC group. However, in the parecoxib pretreatment groups, all the above changes reversed significantly (P<0.05) as compared to the H2O2 treatment group, and were nearly unchanged when compared to the NC group. Mechanical investigation showed that dysregulated Bax, Bcl-2, and BDNF could be implicated in these changes.

Conclusions

Our results indicated that parecoxib provided a protective effect from oxidative stress induced by exposure to H2O2.
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10.

Purpose

Metalloproteinases are a key component of the pathogenesis of abdominal hernias. Obesity is considered a risk factor in herniogenesis and hernia recurrence. The aim of this study was to evaluate the serum concentrations of metalloproteinase-2 (MMP-2), MMP-9, MMP-13, and adiponectin in morbidly obese and nonoverweight controls.

Materials and methods

The participants were recruited from among patients undergoing bariatric and non-bariatric surgery and divided into two groups: I (body mass index (BMI)≥35 kg/m2, n=40) and II (BMI<25 kg/m2, n=30). Serum concentrations of MMP-2, MMP-9, MMP-13, and adiponectin were measured using enzyme-linked immunosorbent assay (ELISA).

Results

A statistically significant difference between groups was observed for MMP-2 concentration. The median MMP-9 concentration was higher in the obese group, but the difference was not statistically significant. Median MMP-13 concentrations did not differ between groups. Serum adiponectin concentration was insignificantly higher in the non-obese group.

Conclusions

The elevated serum MMP-2 and MMP-9 concentrations in obese individuals may be related to the higher incidence of incisional hernias in this population.
  相似文献   

11.

Objective

Scandix pecten-veneris L. is a less studied wild edible herb and is considered an extinct plant species in many parts of the world. This study was designed to evaluate its phytochemical composition and biological potential of S. pecten-veneris L.

Methods

Phytochemicals including alkaloids, flavonoids, polyphenols, and tannins were determined in extracts of S. pecten-veneris. Antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), while reducing power was tested by ferric reducing/antioxidant power (FRAP) assay. Antimicrobial activity against seven bacterial and four fungal strains was evaluated using agar well diffusion assay. Enzymes inhibition study was performed for urease, phosphodiesterase-I, and catalase-II.

Results

S. pecten-veneris showed moderate antiradical activity and reducing potential of hydroxyl radicals to about 20% of the initial value. The antioxidant activity of various extracts of S. pecten-veneris showed a linear correlation with total phenolic contents in the order of water>n-butanol>chloroform>ethyl acetate>methanol extracts. S. pecten-veneris leaves showed the highest inhibitory activity against Staphylococcus aureus while the highest antifungal activity was observed against Candida albicans. The plant extract was most potent against urease enzymes but showed moderate activity against phosphodiestrase-I and carbonic anhydrase-II.

Conclusions

Our data demonstrate that in addition to its culinary uses, S. pecten-veneris has good medicinal potential and hence could be used for treating some specific health ailments.
  相似文献   

12.

Objective

The aim of this study was to formulate polymer-based artesunate nanoparticles for malaria treatment.

Methods

Artesunate was loaded with poly(D,L-lactic-co-glycolic acid) (PLGA) by solvent evaporation from an oil-in-water single emulsion. Nanoparticles were characterized by X-ray diffraction and differential scanning calorimetry analyses. In vivo antimalarial studies at 4 mg/kg were performed on Swiss male albino mice infected with Plasmodium berghei. Hematological and hepatic toxicity assays were performed. In vitro cytotoxicity of free and encapsulated artesunate (Art-PLGA) to cell line RAW 264.7 was determined at concentrations of 7.8–1000 μg/ml.

Results

The particle size of the formulated drug was (329.3±21.7) nm and the entrapment efficiency was (38.4±10.1)%. Art-PLGA nanoparticles showed higher parasite suppression (62.6%) compared to free artesunate (58.2%, P<0.05). Platelet counts were significantly higher in controls (305 000.00±148 492.40) than in mice treated with free artesunate (139 500.00±20 506.10) or Art-PLGA (163 500.00±3535.53) (P<0.05). There was no sign of hepatic toxicity following use of the tested drugs. The half maximal inhibitory concentration (IC50) of Art-PLGA (468.0 μg/ml) was significantly higher (P<0.05) than that of free artesunate (7.3 μg/ml) in the in vitro cytotoxicity assay.

Conclusions

A simple treatment of PLGA-entrapped artesunate nanoparticles with dual advantages of low toxicity and better antiplasmodial efficacy has been developed.
  相似文献   

13.

Objective

Comparison of global end-diastolic volume index (GEDVI) obtained by femoral and jugular transpulmonary thermodilution (TPTD) indicator injections using the EV1000/VolumnView® device (Edwards Lifesciences, Irvine, USA).

Methods

In an 87-year-old woman with hypovolemic shock and equipped with both jugular and femoral vein access and monitored with the EV1000/VolumeView® device, we recorded 10 datasets, each comprising duplicate TPTD via femoral access and duplicate TPTD (20 ml cold saline) via jugular access.

Results

Mean femoral GEDVI ((674.6±52.3) ml/m2) was significantly higher than jugular GEDVI ((552.3±69.7) ml/m2), with P=0.003. Bland-Altman analysis demonstrated a bias of (+122±61) ml/m2, limits of agreement of ?16 and +260 ml/m2, and a percentage error of 22%. Use of the correction-formula recently suggested for the PiCCO® device significantly reduced bias and percentage error. Similarly, mean values of parameters derived from GEDVI such as pulmonary vascular permeability index (PVPI; 1.244±0.101 vs. 1.522±0.139; P<0.001) and global ejection fraction (GEF; (24.7±1.6)% vs. (28.1±1.8)%; P<0.001) were significantly different in the case of femoral compared to jugular indicator injection. Furthermore, the mean cardiac index derived from femoral indicator injection ((4.50±0.36) L/(min·m2)) was significantly higher (P=0.02) than that derived from jugular indicator injection ((4.12±0.44) L/(min·m2)), resulting in a bias of (+0.38±0.37) L/(min·m2) and a percentage error of 19.4%.

Conclusions

Femoral access for indicator injection results in markedly altered values provided by the EV1000/VolumeView®, particularly for GEDVI, PVPI, and GEF.
  相似文献   

14.

Objectives

Spontaneous intracranial hypotension (SIH) is recognized far more commonly than ever before. Though usually characterized by low cerebrospinal fluid (CSF) pressure, some patients with SIH are observed to have normal pressure values. In this study, we aimed to confirm the proportion of patients with normal CSF opening pressure (CSF OP) and explore the factors affecting CSF OP in SIH patients.

Methods

We retrospectively reviewed 206 consecutive SIH patients and analyzed their clinical and imaging variables (including demographic data, body mass index (BMI), duration of symptoms, and brain imaging findings). Univariate and multivariate analyses were performed to identify the potential factors affecting CSF OP.

Results

In a total of 114 (55.3%) cases the CSF OP was ≤60 mmH2O (1 mmH2O=9.806 65 Pa), in 90 (43.7%) cases it was between 60 and 200 mmH2O, and in 2 (1.0%) cases it was >200 mmH2O. Univariate analysis showed that the duration of symptoms (P<0.001), BMI (P<0.001), and age (P=0.024) were positively correlated with CSF OP. However, multivariate analysis suggested that only the duration of symptoms (P<0.001) and BMI (P<0.001) were strongly correlated with CSF OP. A relatively high R 2 of 0.681 was obtained for the multivariate model.

Conclusion

Our study indicated that in patients without a low CSF OP, a diagnosis of SIH should not be excluded. BMI and the duration of symptoms can influence CSF OP in SIH patients, and other potential factors need further investigation.
  相似文献   

15.

Objective

Salmonella enterica remains a major cause of food-borne disease in humans, and Salmonella Typhimurium (ST) contamination of poultry products is a worldwide problem. Since macrophages play an essential role in controlling Salmonella infection, the aim of this study was to evaluate the effect of glycyrrhizic acid (GA) on immune function of chicken HD11 macrophages.

Methods

Chicken HD11 macrophages were treated with GA (0, 12.5, 25, 50, 100, 200, 400, or 800 μg/ml) and lipopolysaccharide (LPS, 500 ng/ml) for 3, 6, 12, 24, or 48 h. Evaluated responses included phagocytosis, bacteria-killing, gene expression of cell surface molecules (cluster of differentiation 40 (CD40), CD80, CD83, and CD197) and antimicrobial effectors (inducible nitric oxide synthase (iNOS), NADPH oxidase-1 (NOX-1), interferon-γ (IFN-γ), LPS-induced tumor necrosis factor (TNF)-α factor (LITAF), interleukin-6 (IL-6), and IL-10), and production of nitric oxide (NO) and hydrogen peroxide (H2O2).

Results

GA increased the internalization of both fluorescein isothiocyanate (FITC)-dextran and ST by HD11 cells and markedly decreased the intracellular survival of ST. We found that the messenger RNA (mRNA) expression of cell surface molecules (CD40, CD80, CD83, and CD197) and cytokines (IFN-γ, IL-6, and IL-10) of HD11 cells was up-regulated following GA exposure. The expression of iNOS and NOX-1 was induced by GA and thereby the productions of NO and H2O2 in HD11 cells were enhanced. Notably, it was verified that nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) pathways were responsible for GA-induced synthesis of NO and IFN-γ gene expression.

Conclusions

Taken together, these results suggested that GA exhibits a potent immune regulatory effect to activate chicken macrophages and enhances Salmonella-killing capacity.
  相似文献   

16.

Background

Leber congenital amaurosis (LCA) is a group of clinically and genetically heterogeneous retinal dystrophy. To date, 22 genes are known to be responsible for LCA, and some specific phenotypic features could provide significant prognostic information for a potential genetic etiology. This study is to identify gene variants responsible for LCA in a Chinese family using direct Sanger sequencing, with the help of phenotype-genotype correlations.

Methods

A Chinese family with six members including two individuals affected with LCA was studied. All patients underwent a complete ophthalmic examination. Based on phenotype-genotype correlation, direct Sanger sequencing was performed to identify the candidate gene on all family members and normal controls. Targeted next-generation sequencing was used to exclude other known LCA genes.

Results

By Sanger sequencing, we identified two novel missense variants in the retinol dehydrogenase 12 (RDH12) gene: a c.164C>A transversion predicting a p.T55K substitution, and a c.535C>G transversion predicting a p.H179D substitution. The two affected subjects carried both RDH12 variants, while their parents and offspring carried only one of heterozygous variants, showing complete cosegregation of the variants. The compound heterozygous variants were not present in 600 normal controls. Besides, the RDH12 variants were confirmed by targeted next-generation sequencing.

Conclusions

The RDH12 compound heterozygous variants might be the cause of the LCA family. Our study adds to the molecular spectrum of RDH12-related retinopathy and offers an effective example of the power of phenotype-genotype correlations in molecular diagnosis of LCA.
  相似文献   

17.

Objective

To investigate the analgesic effects of electroacupuncture (EA) at 2 and 100 Hz on type 2 diabetic neuropathic pain (DNP) and on the expressions of the P2X3 receptor and calcitonin gene-related peptide (CGRP) in the dorsal root ganglion (DRG).

Methods

Rat type 2 DNP was induced by a high calorie and high sugar diet fed for 7 weeks, plus a single intraperitoneal injection of streptozotocin (STZ) after 5 weeks. EA at 2 and 100 Hz was carried out once every day after 7 weeks for 7 consecutive days. Body weight, serum fasting insulin (FINS), fasting blood glucose (FBG), insulin sensitivity index (ISI), and paw withdrawal latency (PWL) were measured. The expressions of L4–L6 DRG P2X3 receptors and CGRP were assessed by immunofluorescence.

Results

Type 2 DNP was successfully induced as shown by the increased body weight, FINS, and FBG, as well as the reduced ISI and PWL. Expressions of P2X3 receptors and CGRP in L4–L6 DRGs increased. EA at both 2 and 100 Hz relieved type 2 DNP, but the analgesic effect of EA was stronger at 2 Hz. P2X3 receptor expression decreased in L4–L6 DRGs following EA at 2 Hz and in L5 and L6 DRGs following EA at 100 Hz. EA at both 2 and 100 Hz down-regulated CGRP overexpression in L4–L6 DRGs.

Conclusions

These findings indicate that EA at 2 Hz is a good option for the management of type 2 DNP. The EA effect may be related to its down-regulation of the overexpressions of the DRG P2X3 receptors and CGRP in this condition.
  相似文献   

18.
19.

Objectives

This study aimed to compare the learning curves of percutaneous endoscopic lumbar discectomy (PELD) in a transforaminal approach at the L4/5 and L5/S1 levels.

Methods

We retrospectively reviewed the first 60 cases at the L4/5 level (Group I) and the first 60 cases at the L5/S1 level (Group II) of PELD performed by one spine surgeon. The patients were divided into subgroups A, B, and C (Group I: A cases 1–20, B cases 21–40, C cases 41–60; Group II: A cases 1–20, B cases 21–40, C cases 41–60). Operation time was thoroughly analyzed.

Results

Compared with the L4/5 level, the learning curve of transforaminal PELD at the L5/S1 level was flatter. The mean operation times of Groups IA, IB, and IC were (88.75±17.02), (67.75±6.16), and (64.85±7.82) min, respectively. There was a significant difference between Groups A and B (P<0.05), but no significant difference between Groups B and C (P=0.20). The mean operation times of Groups IIA, IIB, and IIC were (117.25±13.62), (109.50±11.20), and (92.15±11.94) min, respectively. There was no significant difference between Groups A and B (P=0.06), but there was a significant difference between Groups B and C (P<0.05). There were 6 cases of postoperative dysesthesia (POD) in Group I and 2 cases in Group IIA (P=0.27). There were 2 cases of residual disc in Group I, and 4 cases in Group II (P=0.67). There were 3 cases of recurrence in Group I, and 2 cases in Group II (P>0.05).

Conclusions

Compared with the L5/S1 level, the learning curve of PELD in a transforaminal approach at the L4/5 level was steeper, suggesting that the L4/5 level might be easier to master after short-term professional training.
  相似文献   

20.

Objective

A new therapeutic strategy using nanocomposite scaffolds of grafted hydroxyapatite (g-HA)/poly(lactide-co-glycolide) (PLGA) carried with autologous mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) was assessed for the therapy of critical bone defects. At the same time, tissue response and in vivo mineralization of tissue-engineered implants were investigated.

Methods

A composite scaffold of PLGA and g-HA was fabricated by the solvent casting and particulate-leaching method. The tissue-engineered implants were prepared by seeding the scaffolds with autologous bone marrow MSCs in vitro. Then, mineralization and osteogenesis were observed by intramuscular implantation, as well as the repair of the critical radius defects in rabbits.

Results

After eight weeks post-surgery, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that g-HA/PLGA had a better interface of tissue response and higher mineralization than PLGA. Apatite particles were formed and varied both in macropores and micropores of g-HA/PLGA. Computer radiographs and histological analysis revealed that there were more and more quickly formed new bone formations and better fusion in the bone defect areas of g-HA/PLGA at 2–8 weeks post-surgery. Typical bone synostosis between the implant and bone tissue was found in g-HA/PLGA, while only fibrous tissues formed in PLGA.

Conclusions

The incorporation of g-HA mainly improved mineralization and bone formation compared with PLGA. The application of MSCs can enhance bone formation and mineralization in PLGA scaffolds compared with cell-free scaffolds. Furthermore, it can accelerate the absorption of scaffolds compared with composite scaffolds.
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