Toll-like receptor 4(TLR4)is a member of the TLRs superfamily,mainly capable of identifying bacterial endotoxin,lipopolysaccharides and lipooligosaccharides of Gram-negative bacte?ria cell walls to prevent microbial invasion. Activation of TLR4 can induce production of proinflammato?ry cytokines and inflammatory chemokines and regulate natural immunity. However,dysregulation of TLR4 can lead to autoimmune diseases. This review summarized the biological structure of TLR4 and recognition mechanisms between TLR4 and its ligands,surveyed TLR4 ligands including lipid A ana?logues,natural products and synthetic small molecules,discussed the structure-activity relationship of TLR4 modulators and the ligand-receptor and protein-protein interactions in the complex,and outlined the prospect of future research and development of TLR4 ligands.

BACKGROUND:In the process of cardiac stem cel culture in vitro, the growth microenvironment may have some effects on the cel proliferation.
OBJECTIVE:To investigate the possible mechanism of proliferation and migration of rat cardiac stem cel s cultured in vitro.
METHODS:Cardiac tissues from 10 Sprague-Dawley rats were obtained for primary culture and subculture. Passage 3 cel s were col ected for immunofluorescence staining, and stem cel growth factor receptor (c-kit) and CD45, CD90 were detected. Cultured tissues were col ected and randomly divided into two groups:in group 1, paraformaldehyde fixation, paraffin embedding, hematoxylin-eosin staining, Masson staining, and detecting apoptotic cel s using TUNEL method were conducted;in group 2, EdU labeling of proliferated cel s, immunofluorescent detection of c-kit positive expression, matrix metal oproteinases 2, 9 and transforming growth factorβ1 using immunofluorescent staining were done.
RESULTS AND CONCLUSION:After 7-10 days of myocardial tissue culture, bright and round cel s were visible, and after adhesion, fusiform cel s exhibited strong growth and proliferation ability. Immunofluorescence staining showed a large number of c-kit, CD45 positive cel s but CD90 negative cel s. After culture, a great number of newborn cel s were found, accompanied by apoptosis of myocardial cel s. After EdU staining, the positive cel s were distributed in the myocardial gap, and showed a smal amount of matrix metal oproteinases 2, 9 and transforming growth factorβ1, while in the surrounding myocardium there was a large number of matrix metal oproteinases 2, 9 and transforming growth factorβ1. Taken together, our findings show that cardiac stem cel s could be obtained through myocardial tissue culture in vitro, accompanied by cel proliferation and migration. The mechanism is related to the expression of matrix metal oproteinases 2, 9 and transforming growth factorβ1.

Objective To study the condition and method of hydrodynamics-based transgene(HDT) in rat fatty liver. Methods Inject different dosages and concentrations of green fluorescent protein plasmid pEGFP-C1 at different speeds, then collect 4 rats' liver leaves at different time points after injection and prepare their frozen section, finally observe and quantify the GFP expression with fluo rescence microscope at 488 nm excitation wavelength. Results Plasmid pEGFP-C1 concentration 33mg/L, injection speed 2ml/s, injection volume 8.5%of rat body weight, injected plasmid. After 6 hours of injection, GFP-positive cells rate of pedicel leaf is about 18%, left leaf about 14%, middle leaf about 12.5%;R3ight leaf about 10% and tail leaf about 8%. GFP begin to gradually reduce since 24 hours, until 72 hours almost no GFP-positive cells were checked in all liver leaves. Conclusion Hydrodynamics-based transgene can be applied to rat fatty liver, the appropriate conditions of this method are 33mg/L plasmid concentration, 8.5% rat avoirdupois, 2ml/s injection speed, and the suitable time to observe the proportion of GFP-positive cells is 6-24 hours after gene injection.

OBJECTIVE:To identify Gleditsia sinensis.METHODS:The property,microscopic and TLC characteristics of Gleditsia sinensis were identified.RESULTS:The appearance,microscopic and TLC characteristics of Gleditsia sinensis were obtained.CONCLUSION:The established method is effective for the quality control of the Gleditsia sinensis.

Objective To study the conditions and methods of hydrodynamics-based transgene into rat regenerating liver in vivo. Methods The solution with concentration 30mg/L gene-containing plasmid was injected into rat tail veins at a speed of 2ml/s, then partial hepatectomy (PH) was performed at different times before/after injection, finally the rat (g) and regenerating liver (g) were weighed, and the liver coefficient (Lc) was calculated. Out of 15 groups which are Lc±Lc*0%, *5%, *10%, *15%, *20%, *25%, *30%, *35%, the most suitable group was chosen as correction coefficient to calculate the most appropriate volume of plasmid solution which was injected into the regenerating liver at different recovery times, and at the same time, right lobe of liver was gathered to make frozen section, then observe and quantify the positive green fluorescent protein (GFP) rate at 488 nm excitation wavelength. Results Injection of either physiological saline or empty plasmid has no significant difference compared with control (only PH performance). The appropriate time of hydrodynamics-based transgene is more than 12 hours before PH or anytime after PH. The solution volume of hydrodynamics-based transgene into liver regenerating rat after PH is rat weight (g) ×9%×1/3×corresponding correction coefficient (Trc). Both vector and target gene have effect on the time and abundance of gene expression. Conclusion Hydrodynamics-based transgene can effectively be applied to gene transfection in rat regenerating liver.

To explore the role of methotrexate (MTX) in regulating the number of regulatory T cells (Treg) and the mRNA expression of transcription factor Foxp3.
 Methods: 1) We analyzed the number of Treg and the mRNA expression of Foxp3 by flow cytometry (FCM) and quantitative real-time PCR (qRT-PCR) respectively in patients with psoriasis vulgaris, patients with psoriasis vulgaris after the 8-week treatment of MTX, and healthy people. 2) BALB/c female mice were smeared with imiquimod (IMQ) cream for 6 days. We recorded the change of the lesion in mice every day. The morphological changes of lesion in mice were evaluated by the psoriasis area and severity index (PASI) and HE staining. 3) The mouse model was randomly divided into a control group and an MTX group. The MTX group was treated with different doses of MTX (38.5 and 77.0 nmol/L) on the third day of this experiment. The morphological changes of lesion in mice were evaluated by PASI and HE staining. We tested the number of Treg and the expression level of Foxp3 mRNA in splenic lymphocytes.
 Results: 1) The number of Treg and the expression level of Foxp3 mRNA were lower in psoriasis vulgaris patients than those in the healthy control group (P<0.05). After 8-week treatment of MTX, the number of Treg was increased (P<0.05) and Foxp3 mRNA level was up-regulated (P<0.01). 2) Typical psoriasis-like skin lesions, such as red scaly skin plaque were found after topical application of IMQ. Both the number of Treg in the splenic lymphocytes of mice and the Foxp3 mRNA level of Treg were reduced by IMQ (P<0.01 and P<0.05). 3) Different doses of MTX for mice showed the ability to improve skin lesion, increase the number of Treg in the spleen of mice and Foxp3 mRNA level in psoriatic dermatitis of mice (P<0.05).
 Conclusion: MTX is able to regulate the number of Treg and Foxp3 mRNA expression in psoriasis.
Adjuvants, Immunologic ; pharmacology ; Aminoquinolines ; pharmacology ; Animals ; Case-Control Studies ; Female ; Forkhead Transcription Factors ; metabolism ; Humans ; Imiquimod ; Immunosuppressive Agents ; administration & dosage ; pharmacology ; Lymphocyte Count ; Methotrexate ; administration & dosage ; pharmacology ; Mice ; Mice, Inbred BALB C ; Psoriasis ; drug therapy ; immunology ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Random Allocation ; Spleen ; cytology ; T-Lymphocytes, Regulatory ; cytology ; drug effects ; metabolism