[Role of Orai 1-mediated store-operated calcium entry in the immune function of CD4+ T cells in septic mice]

Objective: To investigate the role of Orai1-mediated store-operated calcium entry in the immune damage of CD4⁺ T cells in septic mice. Methods: Sepsis mouse model was established by cecal ligation and puncture(CLP). Balb/c mice of clean grade were sacrificed 1, 3, and 5 days after operation. Spleen samples were harvested at given intervals. Splenic CD4⁺ T cells were selected by immunomagnetic beads and the expression of Orai1 protein was detected by western blotting, the storage operated calcium entry (SOCE) was detected by flow cytometry, the apoptosis of CD4⁺ T cells was detected by flow cytometry, the proliferation of CD4⁺ T cells was detected by CCK-8, and the IFN-γ and IL-4 were detected by enzyme-linked immunosorbent assay (ELISA). Then the expression of Orai1 protein was regulated to further detect the SOCE and immune function of splenic CD4⁺ T cells in mice. The experiment was divided into 4 groups, sham group, CLP3 group, Orai1 down group (Orai1-down group) and Orai1 up regulation group (Orai1-up group). Results: The relative expression of Orai1 protein in splenic CD4⁺ T cells in sham group was 1.03±0.16. Compared with sham group, Orai1 protein levels in CLP Group were all significantly lower (F=19.64, P=0.000 5). The increased value of splenic CD4⁺ T cells fluorescence intensity in sham group was 494±41. Compared with sham group, the levels of SOCE in CLP Group were all lower (F=30.01, P=0.001). The ratio of early and late apoptosis of CD4⁺ T cells in sham group was 8.7%±1.5%. Compared with sham group, the early and late apoptosis rates of CLP Group were significantly higher (F=32.29, P=0.000 1). The OD of sham group was 0.81±0.10 at 450 nm. Compared with sham group, the proliferation ability of splenic CD4⁺ T cells in CLP Group were significantly decreased (F=7.26, P=0.001 8). Compared with sham group, the secretion of IFN-γ and IL-4 by CD4⁺ T cells and the ratio of IFN-γ/IL-4 in CLP Group were all significantly decreased (F=19.690, 6.183, 11.230, all P<0.05). Compared with CLP3 group, the increased value of fluorescence intensity of CD4⁺ T cells was significantly decreased, the early and late apoptosis ratio of CD4⁺ T cells was significantly increased, the OD450 nm value of CD4⁺ T cells was decreased, the multiplication capacity of splenic CD4⁺ T cells were decreased, the level of IFN-γ and IL-4 secreted by T cells were decreased, and the value of IFN-γ/IL-4 in orai1-down group was decreased (t=4.819, 7.952, 2.988, 28.760, 3.140, 7.670, all P<0.05). However, Orail-up group showed the opposite trend. Conclusion: Orai1-mediated store-operated calcium entry can alleviate the immune dysfunction of CD4⁺ T cells in septic mice.

[Correlation between Movement Distance of Small Intestinal Contents and Survival Time in Female Rats after Feeding]

OBJECTIVES

To study the correlation between the movement distance of small intestinal contents and survival time in female SD rat models after one-time satiation, and to evaluate its application value for postmortem interval estimation.

METHODS

Adult female SD rats were randomly divided into postprandial groups （1, 2, 3, 4 and 5 h after feeding） and control group. The postprandial groups were fed for 1 h, meanwhile control group was kept fasting. All rats were sacrificed at the given time. The contents in stomach and small intestine were observed, described, compared and photographed, and the movement distance of small intestinal contents was measured. The data of postprandial groups were analysed by one-way analysis of variance.

RESULTS

The stomach and duodenum of control group were empty with a little thin and yellow small intestinal liquid. The gastral cavities of 1 h postprandial group were full of undigested food. The evolutionary changes of character, colour and content were observed in the gastric and small intestinal contents of other postprandial groups. The movement distance of intestinal contents increased while the empty part decreased gradually. The differences among the postprandial groups were statistically significant （P<0.05）.

CONCLUSIONS

After a 24 h fasting with free drinking and the following 1 h feeding, an ideal animal model can be established successfully on female SD rats, which can provide an experimental basis for postmortem interval estimation based on the changes of small intestinal contents in forensic practice.

Effect of mannose on the lung function of rats with acute pancreatitis

The present study aimed to investigate the mechanisms by which mannose protects the lung injury induced in rats with acute pancreatitis (AP). An AP combined with Acute Lung Injury (ALI) model was established. A total of 90 healthy adult male Sprague-Dawley rats (300±50g weight) were randomly divided into three groups: sham operation group (SO group), severe acute pancreatitis lung injury group (SAP group), and mannose intervention group (MT group). Subsequently, each group was divided into two subgroups based on the time passed from intervention, namely 6 and 12 h. Each subgroup comprised 15 rats. The ratio of wet/dry weight of the lung tissue exhibited no significant change at different time points in the SO group. This parameter was significantly increased in the SAP group compared with the SO group at each time point of the treatment (P less than 0.05) and it was significantly lower in the MT group than that in the AP group (P less than 0.05) and it was significantly increased in the AP group at each time (P less than 0.05) compared with the SO group. The levels of TNF-α in the lung tissue in the SO group exhibited no significant change at different time points, but they were significantly decreased in the MT group at each time point (P less than 0.05) compared with the SAP group. The mannose receptor (MR) mRNA and protein levels in the lung tissues exhibited no significant change at different time points. The mRNA and protein levels of MR in the SAP group were significantly decreased at each time point (P less than 0.05) compared with the SO group. The mRNA and protein levels of MR, in the lung tissue of the MT group were significantly increased at each time point compared with the SAP group (P less than 0.05). Mannose could reduce the injury caused to the lung tissue of rats with severe acute pancreatitis by up-regulation of the expression of MR mRNA and protein.

[Age Estimation of Adult Living Donor by Pubic MSCT Three-dimensional Reconstruction]

OBJECTIVES

To establish a method for the age estimation of adult living donor based on pubic MSCT three-dimensional reconstruction and verify its accuracy and reliability.

METHODS

The volume rendering （VR） image data of pubic symphysis surface were collected from 300 volunteers aged over 17 years old. According to different age groups, the age estimation of these volunteers was performed by the method and formula of pubic symphysis surface.

RESULTS

In the 300 volunteers, the difference between biological age and actual age was <1 year in 117 cases, >1-2 years in 178 cases, >2 years in 5 cases.

CONCLUSIONS

MSCT three-dimensional reconstruction technology of pubic symphysis surface can be used to estimate the age of adult living donor, which can provide a high accurate and reliable result.

Expression and clinical significance of rhubarb on serum amylase and TNF-alpha of rat model of acute pancreatitis

The aim of this study was to evaluate the therapeutic effect of rhubarb extract on acute pancreatitis. Ninety-six healthy Sprague Dawley rats, weighing 301±5.12 g were randomly divided into 4 groups: sham surgery (group A), acute pancreatitis model (group B), acute pancreatitis with normal saline (group C), and acute pancreatitis model with rhubarb (group D). The levels of serum amylase (AMY) and TNF-α were measured at 1st, 6th, 12th and 24th hour after modeling, and the pancreatic tissue were used to observe the pathologic changes. Compared to the sham group, the serum AMY and serum tumor necrosis factor (TNF-α) levels were significantly increased in the other groups (p <0.05). Compared to the model group and the saline group, the serum AMY, serum TNF-α level and pathological changes of rats in the rhubarb group were significantly lower (p <0.05). The serum AMY and TNF-α levels increased in acute pancreatitis. The rhubarb reduced the serum AMY and TNF-α level in rats with acute pancreatitis and reduced the pathological changes of pancreas and other tissues.

A comparative study of transfection methods for RNA interference in bone marrow-derived murine dendritic cells

Selective gene silencing using RNA interference (RNAi) has been shown to be an efficient method for manipulation of cellular functions. In this study, we compare three previously established methods for transfection of murine bone marrow-derived DC (BM-DC). We tested the efficacy of electroporation with the Mouse Nucleofector kit((R)) from Amaxa Biosystems and lipid-based transfection methods using transfection reagents from Santa Cruz Biotechnology or Genlantis. To analyse the transfection efficacy we used FITC-conjugated siRNA as a positive control together with CD80 and CD86 specific siRNA. We show that electroporation using the Mouse Nucleofector kit((R)) from Amaxa Biosystems was not an efficient method to transfect BM-DC with siRNA in our hands. Transfection with Santa Cruz Biotechnology reagents resulted in up to 59% FITC-siRNA positive cells, but did not result in effective silencing of CD80 surface expression. In contrast, the most effective method was the lipid-based method using the siRNA transfection reagent GeneSilencer((R)) from Genlantis. This protocol resulted in up to 92% FITC-siRNA positive cells after 4 h which declined to 62% and 59% 24 and 48 h post-transfection, respectively. The transfected BM-DC remained CD11c positive, expressed high MHC class II and intermediate CD40 and were functional as APC. In conclusion, this protocol was effective for manipulation of murine BM-DC function through the use of specific siRNA and such methods can be important for the future study of DC-T cell interactions.

The IFN regulatory factor family participates in regulation of Fas ligand gene expression in T cells

TCR engagement leads to the transcriptional activation of cytokine genes and activation-induced cell death. Activated T cells undergo apoptosis upon expression and ligation of Fas ligand (FasL) to Fas/APO-1 (CD95) receptor. FasL expression is under the transcriptional regulation of multiple factors. The present study demonstrates that TCR-inducible FasL expression is also under the direct influence of the IFN regulatory factor (IRF) transcription factor family. Deletion and mutagenesis of a putative IRF-1 binding site in the FasL promoter results in deficient expression of FasL. EMSAs demonstrate specific FasL promoter binding by IRF-1 and IRF-2. Forced expression of either IRF-1 or IRF-2 leads to FasL promoter activation in T cells and FasL expression in heterologous cells. Finally, suppression of IRF-1 expression in T cells results in deficient TCR-induced FasL expression. These results confirm that the IRF family participates in the regulation of FasL gene expression.

Portable system for quantifying motor abnormalities in Parkinson's disease

In order to quantify motor disabilities in Parkinson's disease (PD), we designed a compact, portable, neurophysiological system based upon a personal computer to measure tremor, bradykinesia, and muscle tone. Tremor was detected by solid state accelerometers and translated into a digital signal. The system displayed the root mean square displacements and frequency distribution of the tremor in the horizontal and vertical planes, along with a reconstructed graphic image of the displacement. Bradykinesia was measured using a panel that detects release and depression of switches in response to auditory and visual signals; the system calculated subjects' reaction times and movement times in milliseconds. Tone at the elbow was measured by strapping the upper extremity to a lightweight low-friction cradle and then passively moving the cradle with an instrumented handle. Signals representing torque and arm angle were processed by the computer and displayed in real time on the screen with stiffness as a mean slope in Nm/degree. In clinical tests, quantitative measures of tremor, movement time and rigidity were significantly abnormal in PD patients compared to control subjects. We conclude that this system is a convenient and accurate method to quantitate important aspects of the parkinsonian syndrome, and may be applied to quantitate other movement disorders.