Regulation of cyp26a1 on Th17 cells in mouse peri‐implantation

Cytochrome P450 26A1 (cyp26a1) is expressed in the mouse uterus during peri‐implantation. The repression of this protein is closely associated with a reduction in implantation sites, suggesting a specific role for cyp26a1 in pregnancy and prompting questions concerning how a metabolic enzyme can generate this distinct outcome. To explore the effective downstream targets of cyp26a1 and confirm if its role in peri‐implantation depends on its metabolic substrate RA (retinoic acid), we characterized the changes in the peripheral blood, spleen and uterine implantation sites using the cyp26a1 gene vaccine constructed before. Flow cytometry results showed a significant increase in CD4⁺RORγt⁺ Th17 cells in both the peripheral blood and spleen in the experimental group. The expression of RORγt and IL‐17 presented the Th17 cells reduction in uterus followed by the suppression of cyp26a1 expression. For greater certainty, cyp26a1 antibody blocking model and RNA interference model were constructed to determine the precise target immune cell group. High performance liquid chromatography results showed a significant increase in uterine at‐RA followed by the immunization of cyp26a1 gene vaccine. Both the ascertain by measuring RARα protein levels in peri‐implantation uterus after gene vaccine immunization and researches using the specific agonist and antagonist against RARα suggested that RARα may be the main RA receptor for signal transduction. These results provided more evidence for the signal messenger role of RA in cyp26a1 regulation from the other side. Here, we showed that the cyp26a1‐regulated Th17 cells are dependent on at‐RA signalling, which is delivered through RARα in mouse peri‐implantation.     

Tumor extracellular acidity-activated nanoparticles as drug delivery systems for enhanced cancer therapy

pH-responsive nanoparticles (NPs) are currently under intense development as drug delivery systems for cancer therapy. Among various pH-responsiveness, NPs that are designed to target slightly acidic extracellular pH environment (pH_e) of solid tumors provide a new paradigm of tumor targeted drug delivery. Compared to conventional specific surface targeting approaches, the pH_e-targeting strategy is considered to be more general due to the common occurrence of acidic microenvironment in solid tumors. This review mainly focuses on the design and applications of pH_e-activated NPs, with special emphasis on pH_e-activated surface charge reversal NPs, for drug and siRNA delivery to tumors. The novel development of NPs described here offers great potential for achieving better therapeutic effects in cancer treatment.     

Negative Interference by Rheumatoid Factor of Plasma B-Type Natriuretic Peptide in Chemiluminescent Microparticle Immunoassays

Background

The chemiluminescent microparticle immunoassay (CMIA) is widely used for the quantitative determination of B-type natriuretic peptide (BNP) in human ethylenediaminetetraacetic acid plasma. Rheumatoid factor (RF) is usually thought to result in a positive interference in immunoassays, but it is not clear whether its presence in plasma can lead to interferences in the CMIA of BNP.

Methods

The estimation of BNP recovery was carried out by diluting high-concentration BNP samples with RF-positive or RF-negative plasma at a ratio of 1∶9. The diluted samples were then tested using the ARCHITECT i2000 System and ARCHITECT BNP Reagent Kits and the recovery was then calculated.

Results

When the RF level ranged from 48 to 1420 IU/mL, the average recovery of BNP was 79.29% and 91.61% in the RF-positive and RF-negative plasma samples, respectively, and was thus significantly lower in the group of RF-positive plasma samples than in the group of RF-negative plasma samples. At a dilution of 1∶16, the measured BNP level increased by >36% in six of the seven RF-positive plasma samples. The recovery of BNP increased significantly in the RF-positive plasma samples after pretreatment with IgG-sensitive latex particles. In addition, The BNP recovery was not significantly related to the plasma RF at concentrations ranging from 48 to 2720 IU/mL.

Conclusions

Measurement of BNP by CMIA is susceptible to interference from RF leading to predominantly (but not exclusively) lower results. Pretreatment of samples with blocking reagents is advisable prior to the initiation of denying patient''s necessary treatment.     

Alfalfa (Medicago sativa L.)/Maize (Zea mays L.) Intercropping Provides a Feasible Way to Improve Yield and Economic Incomes in Farming and Pastoral Areas of Northeast China

Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping modes of maize and alfalfa, a field experiment was conducted in a completely randomized block design with five treatments: maize monoculture in even rows, maize monoculture in alternating wide and narrow rows, alfalfa monoculture, maize intercropped with one row of alfalfa in wide rows and maize intercropped with two rows of alfalfa in wide rows. Results demonstrate that maize monoculture in alternating wide and narrow rows performed best for light transmission, grain yield and output value, compared to in even rows. When intercropped, maize intercropped with one row of alfalfa in wide rows was identified as the optimal strategy and the largely complementary ecological niches of alfalfa and maize were shown to account for the intercropping advantages, optimizing resource utilization and improving yield and economic incomes. These findings suggest that alfalfa/maize intercropping has obvious advantages over monoculture and is applicable to the farming and pastoral areas of northeast China.     

A Three Dimensional Study of Upper Airway in Adult Skeletal Class II Patients with Different Vertical Growth Patterns

Objective

The study was performed to compare the 3D pharyngeal airway dimensions in adult skeletal Class II patients with different vertical growth patterns (low, normal, and high angle) and to investigate whether the upper airway dimensions of untreated skeletal Class II adults were affected by vertical skeletal variables.

Methods

Cone-beam computed tomography (CBCT) records of 64 untreated adult skeletal Class II patients (34 male and 30 female) were collected to evaluate the pharyngeal airway dimensions. Subjects were divided into three subgroups according to the GoGn-SN angle (low angle, normal angle or high angle). All subgroups were matched for sex. ANOVA and SNK - q tests were used to identify differences within and among groups (p<0.05). Coefficient of product-moment correlation (Pearson correlation coefficient) was used to analyze the association between pharyngeal airway dimensions and vertical growth patterns.

Results

The results showed that pharyngeal airway measurements were statistically significantly less (p<0.05) in high angle group as compared to normal angle or low angle group.

Conclusions

Adult skeletal Class II subjects with vertical growth patterns have significantly narrower pharyngeal airways than those with normal or horizontal growth patterns, confirming an association between pharyngeal airway measurements and a vertical skeletal pattern.     

A Proteomic Analysis of Placental Trophoblastic Cells in Preeclampsia–Eclampsia

To explore the proteomic changes of placental trophoblastic cells in preeclampsia–eclampsia (PE), placental trophoblastic cells from normally pregnant women and women with hypertension during gestational period were prepared by laser capture microdissection (LCM), and proteins isolated from these cells were subjected to labeling and proteolysis with isotope-coded affinity tag reagent. A qualitative and quantitative analysis of the proteome expression of placental trophoblastic cells was made using two-dimensional liquid chromatography tandem mass spectrometry (2D LC–MS/MS). A total of 831 proteins in placental trophoblastic cells were identified by combined use of LCM technique and 2D LC–MS/MS. The result was superior to that of conventional two-dimensional electrophoresis method. There were marked differences in 169 proteins of placental trophoblastic cells between normally pregnant women and women with PE. Of 70 (41.4 %) proteins with more than twofold differences, 31 proteins were down-regulated, and 39 were up-regulated in placental trophoblastic cells of the woman with PE. Laminin expression in placenta trophoblastic cells of women with PE was significantly down-regulated as confirmed by Western blot analysis. These findings provide insights into the proteomic changes in placental trophoblastic cells in response to PE and may identify novel protein targets associated with the pathogenesis of PE.     

Changes in Ca, Cu, Fe, Mg, and Zn contents in mouse brain tissues after prolonged oral ingestion of brick tea liquor containing a high level of Al

A study was conducted to analyze the regional distribution of Ca, Cu, Fe, Mg, and Zn contents in brain tissues after animals were given liquor of brick tea that contained a high Al content. In 25 normal adult male mice given either water or 0.9% NaCl for 1 mo or 2 mo, the metal concentrations in the serum, liver, frontal cortex, hippocampus, cerebellum, and brain stem were comparable (p>0.05). When the drinking water was replaced by a 1% brick tea liquor, which contained a high Al content, serum Al concentration was increased significantly 1 mo after the onset of the experiment and remained high at the end of the second month. The level of Al was also elevated in both the cortex and hippocampus at 1 mo after replacing tea for drinking water. In addition to Al, there were a significant increase in hippocampal Zn and a decrease in Cu contents. There was no change in tissue Mg or Fe contents, but there was a significant increase in Ca content in every brain region studied. It was suggested that the increase in Ca might be the result of the effect of other components in tea. Unlike the brain, there was no change in the concentration of any of the metals, including Al, in the liver, which further demonstrated that the changes observed in the brain was specific. The results of the present study confirmed that Al, when given orally in the form of tea, could be absorbed into the bloodstream. The absorbed Al could accumulate in selected brain regions. The presence of Al might also change the tissue content of endogenous trace metals.     

轮状病毒疫苗研究进展及其转基因植物疫苗的开发前景

轮状病毒是目前婴幼儿秋冬季腹泻的最主要病原物,作者通过轮状病毒减毒株疫苗,亚单位疫苗和DNA疫苗研究进展的综合分析,指出了减毒株疫苗在实际应用中存在的弊端,论述了开发新型轮状病毒疫苗,特别是转基因植物疫苗的必要性和可行性。