Lycium barbarum polysaccharide protects against LPS-induced ARDS via an Akt/eNOS signaling pathway / 中国药理学通报

Aim To investigate the effects of Lycium barbarum polysaccharide ( LBP ) on LPS-induced ARDS in mice and the potential mechanisms. Methods Thirty-two C57BL/6 male mice were randomly divided into control group, LPS group, LBP group and LY294002 ( Akt inhibitor) group, with eight mice in each group. The pathological changes in lung tissues were evaluated by HE staining, pulmonary edema was measured by wet/dry ratio( W/D) , and the concentra-tions of total protein and the levels of inflammatory cy-tokines in BALF were determined. MDA and SOD lev-els in lung tissues and the apoptosis of lung tissues were detected. The protein expression levels of cleaved caspase-3, p-Akt and p-eNOS were determined by Western blot. Results Compared with control group, severe pathological lung injury changes were observed in LPS group, and the W/D ratio, levels of total pro-tein and inflammatory cytokines in BALF, levels of MDA in lung tissues and the expression of cleaved caspase-3 significantly increased(P<0.05), while the lung SOD activity, the p-Akt and p-eNOS expression decreased( P<0.05) . LBP could significantly attenu-ate the indexes above(P<0.05). However, the pro-tective effects of LBP on ARDS were inhibited by Akt inhibitor LY294002. Conclusions LBP protects a-gainst LPS-induced ARDS in mice by alleviating EC barrier dysfunction via the suppression of inflamma-tion, oxidative stress and apoptosis, at least partially via activation of the Akt/eNOS singaling pathway.

Vaspin protects against lipopolysaccharide-induced acute respiratory distress syndrome in mice by inhibiting inflammation and protecting vascular endothelium via PI3K/Akt signal pathway / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of Vaspin on lipopolysaccharide (LPS)-induced acute respiratory distress syndrome (ARDS) in mice and explore the possible mechanism.</p><p><b>METHODS</b>Forty male C57B/L6 mice were randomized equally into control group, LPS group, Vaspin group and wortmannin group with corresponding treatments. The pathological changes of the lung tissues were evaluated by HE staining, and the severity of pulmonary edema was measured according to the wet/dry ratio (W/D) of the lung tissue. The lung permeability was evaluated by detecting total protein concentrations in the bronchoalveolar lavage fluid (BALF) using bicinchoninic acid (BCA) assay. Myeloperoxidase (MPO) activity in the lung tissue was detected using a MPO assay kit, and the levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the lungs were measured using ELISA. Immunohistochemical staining was performed to detect the expression of vascular cell adhesion molecule-1 (VCAM-1) and Western blotting was used to detect the protein expressions of cleaved caspase-3 and p-Akt in the lung tissues.</p><p><b>RESULTS</b>Compared with the control group, the mice in LPS group displayed typical ARDS pathological changes in the lungs with significantly increased W/D, total protein concentrations in BALF, lung MPO activity, levels of IL-1β and TNF-α, and pulmonary expressions of VCAM-1 and cleaved caspase-3 (P<0.05) but decreased expression of p-Akt (P<0.05). These changes induced by LPS were significantly alleviated by the administration of Vaspin (P<0.05). The protective effects of Vaspin against ARDS were obviously attenuated by the PI3K inhibitor wortmannin (P<0.05).</p><p><b>CONCLUSION</b>Vaspin protects against LPS-induced ARDS in mice possibly by inhibiting inflammation and protecting vascular endothelium through upregulation of the PI3K/Akt signal pathway.</p>

Extent of Lung Involvement and Serum Cryptococcal Antigen Test in Non-Human Immunodeficiency Virus Adult Patients with Pulmonary Cryptococcosis / 中华医学杂志(英文版)

<p><b>Background</b>Serum cryptococcal antigen (CrAg) test is the most used noninvasive method to detect cryptococcal infection. However, false-negative CrAg test is not uncommon in clinical practice. Then, the aim of this study was to investigate the factors associated with false-negative CrAg test among non-human immunodeficiency virus (HIV) adult patients with pulmonary cryptococcosis and its clinical features.</p><p><b>Methods</b>One hundred and fourteen non-HIV adult patients with pulmonary cryptococcosis, proven by biopsy, were retrospectively reviewed. Finally, 85 patients were enrolled; 56 were CrAg positive (CrAg+ group) and 29 were negative (CrAg- group). It was a cross-sectional study. Then, baseline characteristics, underlying diseases, clinical symptoms, laboratory findings, and chest radiological findings were reviewed and analyzed. Chi-square test was used to analyze categorical variable. Odds ratio (OR) was used to measure correlation. Student's t- test was obtained to analyze continuous variable.</p><p><b>Results</b>No difference in baseline characteristics, underlying diseases, clinical symptoms, and laboratory findings were found between two groups (P > 0.05 in all). Nevertheless, diffuse extent lesion was 82.1% in CrAg+ group and 10.3% in CrAg- group (χ = 40.34, P < 0.001; OR = 39.87).</p><p><b>Conclusions</b>Among patients with limited pulmonary involvement, a negative serum CrAg does not preclude the diagnosis of pulmonary cryptococcosis. However, among patients with extensive pulmonary involvement, serum CrAg is a useful diagnostic tool for pulmonary cryptococcosis. Furthermore, we also noticed that the untypical and mild presentations with extensive pulmonary lesion might be the features of pulmonary cryptococcosis, which needs further investigation.</p>

Role of interleukin-17 in alveolar fluid clearance in mice with acute lung injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of interleukin-17 (IL-17) in alveolar fluid clearance in mice with acute lung injury (ALI) and explore the possible mechanism.</p><p><b>METHODS</b>Sixteen IL-17-knockout mice and 16 wild-type mice were both randomized for intratracheal instillation of PBS (control) on lipopolysaccharide (LPS) to induce ALI. Forty-eight hours after the treatments, the wet-dry ratio (W/D) of the lungs, IL-8 in the bronchoalveolar lavage fluid (BALF) and histopathological changes of the lung tissues were examined. The expressions of epithelial sodium channel α subunit (α-ENaC) was detected with Western blotting and liver kinase B1 (LKB1) was detected with immunohistochemistry.</p><p><b>RESULTS</b>Compared with wild-type mice treated with LPS, IL-17 knockout mice showed significantly decreased W/D of the lungs (9.739∓3.3 vs 5.351∓0.56) and IL-8 level in the BALF (67.50∓7.33 vs 41.00∓3.16 pg/mL) following LPS challenge. Pathological examination revealed reduced alveolar edema fluid aggregations and lower lung injury score in IL-17 knockout mice with also higher expression levels of ENaC and LKB1 compared with the wild-type mice.</p><p><b>CONCLUSION</b>Knocking out IL-17 in mice not only alleviates inflammation of the lung tissue following ALI but also reduces the loss of ENaC protein and promotes alveolar fluid clearance, mechanism of which is probably associated with LKB1.</p>

Rosuvastatin attenuates mucus secretion in a murine model of chronic asthma by inhibiting the gamma-aminobutyric acid type A receptor / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Asthma is a chronic inflammatory disease characterized by reversible bronchial constriction, pulmonary inflammation and airway remodeling. Current standard therapies for asthma provide symptomatic control, but fail to target the underlying disease pathology. Furthermore, no therapeutic agent is effective in preventing airway remodeling. A substantial amount of evidence suggests that statins have anti-inflammatory properties and immunomodulatory activity. In this study, we investigated the effect of rosuvastatin on airway inflammation and its inhibitory mechanism in mucus hypersecretion in a murine model of chronic asthma.</p><p><b>METHODS</b>BALB/c mice were sensitized and challenged by ovalbumin to induce asthma. The recruitment of inflammatory cells into bronchoalveolar lavage fluid (BALF) and the lung tissues were measured by Diff-Quik staining and hematoxylin and eosin (H&E) staining. ELISA was used for measuring the levels of IL-4, IL-5, IL-13 and TNF-α in BALF. Periodic acid-Schiff (PAS) staining was used for mucus secretion. Gamma-aminobutyric acid type A receptor (GABAAR) β2 expression was measured by means of immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting.</p><p><b>RESULTS</b>Rosuvastatin reduced the number of total inflammatory cells, lymphocytes, macrophages, neutrophils, and eosinophils recruited into BALF, the levels of IL-4, IL-5, IL-13 and TNF-α in BALF, along with the histological mucus index (HMI) and GABAAR β2 expression. Changes occurred in a dose-dependent manner.</p><p><b>CONCLUSIONS</b>Based on its ability to reduce the inflammatory response and mucus hypersecretion by regulating GABAAR activity in a murine model of chronic asthma, rosuvastatin may be a useful therapeutic agent for treatment of asthma.</p>

Regulation of epithelial sodium channel α-subunit expression by adenosine receptor A₂a in alveolar epithelial cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The amiloride-sensitive epithelial sodium channel α-subunit (α-ENaC) is an important factor for alveolar fluid clearance during acute lung injury. The relationship between adenosine receptor A(2a) (A(2a)AR) expressed in alveolar epithelial cells and α-ENaC is poorly understood. We targeted the A(2a)AR in this study to investigate its role in the expression of α-ENaC and in acute lung injury.</p><p><b>METHODS</b>A549 cells were incubated with different concentrations of A(2a)AR agonist CGS-21680 and with 100 µmol/L CGS-21680 for various times. Rats were treated with lipopolysaccharide (LPS) after CGS-21680 was injected. Animals were sacrificed and tissue was harvested for evaluation of lung injury by analysis of the lung wet-to-dry weight ratio, lung permeability and myeloperoxidase activity. RT-PCR and Western blotting were used to determine the mRNA and protein expression levels of α-ENaC in A549 cells and alveolar type II epithelial cells.</p><p><b>RESULTS</b>Both mRNA and protein levels of α-ENaC were markedly higher from 4 hours to 24 hours after exposure to 100 µmol/L CGS-21680. There were significant changes from 0.1 µmol/L to 100 µmol/L CGS-21680, with a positive correlation between increased concentrations of CGS-21680 and expression of α-ENaC. Treatment with CGS-21680 during LPS induced lung injury protected the lung and promoted α-ENaC expression in the alveolar epithelial cells.</p><p><b>CONCLUSION</b>Activation of A(2a)AR has a protective effect during the lung injury, which may be beneficial to the prognosis of acute lung injury.</p>

Application of integra for reconstruction of burn scar contracture / 中华整形外科杂志

<p><b>OBJECTIVE</b>Introducing a comprehensive technique to reconstruct burn scar contracture or deformities using integra (artificial dermis) with large epidermal skin grafting or ulth-thin split-skin.</p><p><b>METHODS</b>The wounds following contracture scar or deformities excised or loose were covered with the integra which was flattened and fixed perfectly, after a 2 approximately 4-week period, the out layer was removed then covered with large sheets of epidermal grafts, which was of thickness from 0.0028 inc to 0.0048inc (0.07 approximately 0.12 mm), or ulth-thin split-skin of about 0.006inc (0.15 mm) thickness, harvested using the electric or air power dermatome, the edge of the graft sheet attached together with the borders of wound using nanoparticles-Ag-gauze stripe adding sutures of the 5-0 threads or the skin stapler, dressed with vaseline gauzes in the inner layer and the nano-particles Ag gauze on the outer surfaces.</p><p><b>RESULTS</b>Nineteen sites of 15 cases including 5 sites in trunk and 14 sites in extremities from 1999.8 to 2003.6 were treated using this technique in this study, the wound areas following scar excised was about 10 cm x 25 cm approximately 30 cm x 75 cm, of them 12 cases covered with a large sheet of ultr-thin split-skin (in early time) and 7 cases with a large sheet of epidermal grafting and all of them was survival. The colour and texture of the reconstruction sites were very good and can be compared favorably with normal skin after a half year-four year following up period, because all donor sites healing without scarring, the appearance in the epidermal graft donor is better than that in split-thickness skin donor.</p><p><b>CONCLUSIONS</b>Integra with large sheets of epidermal grafts applied for scar contracture disformities is an effective and useful method, especially the epidermal grafts offered a satisfying result in the donor healing.</p>

Experimental study on the skeletal muscle reconstruction with autologous fascia as a scaffold / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the feasibility of autologous fascia as a scaffold for the reconstruction of skeletal muscle in vivo.</p><p><b>METHODS</b>Twenty-eight healthy New Zealand rabbits were employed in the study. The anterior tibial muscle in both legs were divided to create a gap of 10 mm in each muscle. One leg was used in the experiment (E, n = 28), while the contralateral as self-control (C). The legs in C group were further divided into 3 groups (C1, C2 and C3). While defects in the midportion of anterior tibial muscle in the hind legs were created in all rabbits. In E group, each defect was filled with a tubule made of autologous fascia lata, and the fascial tubule was filled with tiny muscular granules (< 1 mm x 1 mm x 1 mm). In C1 group (n = 10), the defect was also filled with fascial tubule but with no muscle filling. The defect in C2 group (n = 10) was only filled with muscle granules without fascial tubule. The defect in C3 group (n = 8) received no treatment. The survival rate of the transplantation was grossly observed, and the tissue samples were harvested for histological and ultra-structural examination and immunohistochemical identification of desmin at 2, 3, 4, 6 and 9 post-operation weeks. The expression level of alpha-actin DNA in the tissue samples from the midportion of grafted fascia was assessed by RT-PCR (reverse transcription polymerase chain reaction) in E and C1 groups.</p><p><b>RESULTS</b>(1) Survival rate of the transplantation: In E group, it was 93.33% with near normal tissue contour in the grafting area. The muscle defects were not completely repaired in C1, C2 and C3 groups. (2) Under light and electronic microscopy, marked proliferation of muscular cells surrounding fibrous tissue could be discerned at 2 and 3 post-operation weeks in E group, while only necrotic tissue and fibrosis were observed in C1 and C2 groups, and no definite tissue could be discernible in C3 group. (3) Immunohistochemical staining revealed that over 85% of the cells were positive for desmin in E group, while only less than 25% in C1 group. (4) The expression level of alpha-actin DNA was significantly higher in E group than that in C2 group (P < 0.05).</p><p><b>CONCLUSION</b>These results suggested that autologous fascia as a scaffold is beneficial for skeletal muscle reconstruction in vivo.</p>

Mechanism of the role of electrical field in electrical injury / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the acting mechanism of electrical field in electrical injury.</p><p><b>METHODS</b>Thirty-six New Zealand white rabbits were employed in the study and were randomly divided into 7 groups. There were 12 rabbits in group 1 and 4 in each group of other 6 groups. The animal model of nonthermal electrical injury previously replicated was employed in the study. Experiment with paralleled muscular fibers in electrical field was carried out in groups 2 approximately 4, while that of vertical muscular fibers in electrical field in groups 5-7. Anatomical examination was done to determine the index of deep burn injury (IDBI) in all groups of rabbits at 0, 2 and 24 postburn hour (PBH). Histological and ultrastructural examination, gamma picturing and isotope scanning with 99mTc were done in group 1 at 2 PBH.</p><p><b>RESULTS</b>There was no obvious skin injury in the white rabbits in group 1. Deep tissue necrosis was identified under the small electrode. Constant muscular spasm was observed in the inner side of the thigh. The muscles in paralleled electrical field suffered more severe injury than those in vertical one. Tissue injury was more severe in those areas with higher current density, less soft tissue, and also in the central area of the axis of the electric field. There were obvious changes in the perfusion and blood pool phases in these areas as observed with the aid of 99mTc. Light microscopic examination revealed swelling and necrosis of muscular fibers. Under electron microscopy, it was found that there were edema and dissolution with separation of lipid molecular layers of cell membrane, Shortened nucleus with partial dissolution of nuclear membrane, increased heparin granules within nucleus, swelling of mitochondria and endoplasmic reticulum, myofilament dissolution, expanded gap between myofilament and decreased number of heparin granules.</p><p><b>CONCLUSION</b>Non-thermal tissue injury in the electrical field, in terms of cell, ultrastructural and molecular levels, was induced and aggravated by all the factors constituting high voltage electrical field.</p>