Experimental treatment of radiation pneumonitis with human umbilical cord mesenchymal stem cells

OBJECTIVE@#To evaluate of the curative effect of human umbilical cord mesenchymal stem cells (hUC-MSCs) on rat acute radiation pneumonitis.@*METHODS@#Fourty rats were randomly divided into control group, radiation group, stem cell prevention group, stem cell treatment group and prednisone treatment group. All rats except those in the control group were radiated with X ray to establish the acute radiation pneumonitis damage model. The hUC-MSCs cultured in vitro was administrated to the rats of the prevention group via tail vein (1×10(6) cells/kg BW) 24 h before the radiation, while the same administration was performed in the rats of the treatment group 24 h after the radiation. After 24 h post the radiation, the rats in the radiation group were given 0.4 mL physiological saline, and those in the prednisone group were given 1 mg/kg prednisone. All rats were observed and executed 72 h after the radiation to detect lung histological changes.@*RESULTS@#After the administration of hUC-MSCs, the survival status of the rats in the prevention group and treatment group was obviously better than that in the control group. As shown by the histological staining, the morphology, proliferation activity and bronchial state of lung tissues were better in the prevention group and treatment group than in the control group.@*CONCLUSIONS@#The hUC-MSCs have definite therapeutic effects on acute radiation pneumonitis in rats.

Expression change of TNF-α in myocardium and hepatic tissue of rats with compound stress of hyperthermia and lipopolysaccharide

OBJECTIVE@#To investigate the expression characteristics of TNF-α in myocardium and hepatic tissue of rats with compound stress of hyperthermia and lipopolysaccharide (LPS).@*METHODS@#Male SPF Wistar rats were randomly divided into room temperature+physiological saline group (Group C), hyperthermia+physiological saline group (Group H), room temperature+LPS group (Group L) and hyperthermia+LPS group (Group HL). The rats were put in simulated climate cabin. Group HL and Group H were exposed in the environment at a dry bulb temperature (TDB) of (35.0±0.5) °C, while Group L and Group C were exposed in the environment at a TDB of (26.0±0.5) °C. The rats in Group HL and Group L were given tail intravenous injection of LPS 10 mg/kg, while the rats in Group H and Group C were given tail intravenous injection of 9 g/L NaCl 10 mL/kg. After the stress, immunohistochemical SABC staining method was used to detect the expression characteristics of TNF-α in myocardium and hepatic tissue of rats, and those rats were given routine pathological examinations.@*RESULTS@#The expression of TNF-α in myocardium and hepatic tissue in Group HL was enhanced remarkably, and the tissue damages of Group HL were severest.@*CONCLUSIONS@#The cardiotoxicity and hepatotoxicity caused by compound stress of hyperthermia and LPS is closely related to the expression of TNF-α.

An experimental study of preventing and treating acute radioactive enteritis with human umbilical cord mesenchymal stem cells

OBJECTIVE@#To test the curative effect of human umbilical cord-derived mesenchymal stem cells on rat acute radioactive enteritis and thus to provide clinical therapeutic basis for radiation sickness.@*METHODS@#Human umbilical cord-derived mesenchymal stem cells were cultivated in vitro and the model of acute radioactive enteritis of rats was established. Then, the umbilical cord mesenchymal stem cells were injected into the rats via tail vein. Visual and histopathological changes of the experimental rats were observed.@*RESULTS@#After the injection, the rats in the prevention group and treatment group had remarkably better survival status than those in the control group. The histological observations revealed that the former also had better intestinal mucosa structure, more regenerative cells and stronger proliferation activity than the latter.@*CONCLUSIONS@#Human umbilical cord-derived mesenchymal stem cells have a definite therapeutic effect on acute radioactive enteritis in rats.

Changes of serum urea and creatinine concentrations in rats with lipopolysaccharide and heat co-exposure / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of lipopolysaccharide (LPS) and heat co-exposure on serum urea and creatinine (Cr) concentrations in rats.</p><p><b>METHODS</b>Male Wistar rats were randomized into normothermic saline injection control group (group C), heat exposure saline injection group (group H), normothermic LPS injection group (group L), and heat exposure LPS injection group (group HL). The rats in groups H and HL were exposed to heat in a chamber at an dry bulb temperature (Tdb) of 35.0-/+0.5 degrees Celsius, and those in groups C and L were kept in a chamber at Tdb of 26-/+0.5 degrees Celsius. LPS (8 mg/kg) was injected via the tail vein in the rats in groups L and HL to induce endotoxemia, while those in groups C and H were given normal saline injection (8 ml/kg) via the tail vein. The serum levels of urea and Cr were determined at the time points of 0, 40, 80, and 120 min after the injections.</p><p><b>RESULTS</b>No significant difference was found in serum Cr level at any level of the main effects of time, drug, or Tdb (P>0.05), but serum urea level varied significantly between the different time points, different levels of Tdb, and the drug injections (P<0.01). Significant interactions were identified between the time after injection, injected agents, and Tdb (P<0.01). Except for those in the group C, all rats showed elevated serum urea levels 40 min after the injection, particularly those in group HL. The serum urea levels were positively correlated to the level of tumor necrosis factor-alpha (P<0.01).</p><p><b>CONCLUSION</b>Co-exposure to LPS and heat in rats may elicit and worsen systemic inflammatory response syndrome and kidney injury.</p>

Repair of spinal cord injury: Advancement in methods / 第二军医大学学报

Traditionally, spinal cord injuries are conceived unrepairable because the injured neurons can not regenerate. However, recent studies proved that axons of the central nerves system could regenerate under some specified conditions. Inspiring results had been obtained in several milestone researches at organ, cell and molecule levels. Currently a consensus has been reached in the neurology circle that spinal cord injuries are repairable, but the past studies had shortcomings such as defective experiment designing and unsatisfactory repeatability. This article reviews the advance in the repair methods of spinal cord injury, providing reference for future studies.