Objective To investigate the effects of cromolyn sodium(CS)on forebrain ischemiareperfusion injury in gerbils.Methods Twenty-four male gerbils weishing 55-70 g were randomly divided into 3 groups(n=8 each):group Ⅰ sham operation;groupⅡ I/R and group Ⅲ CS 50 mg/kg+I/R.Forebrain ischemia was produced by occlusion of bilateral common carotid arteries for 10 min and confirmed by isoelectricity of EEG. CS was injected via lingual vein at 0 and 1 h of reperfusion.All the animals were killed at 2 h of reperfusion for determination of cerebral cortex injury score,cerebral water content[(wet weight-dry weight)/wet weight×100%],cerebral MDA content,SOD activity and histamine content.Results The cerebral cortex injury 8core,cerebral water content, MDA content and histamine content were significantly increased while SOD activity was signiiieantly decreased in I/R group(Ⅱ)aa compared with sham operation group(Ⅰ)(P＜0.05 or 0.01).CS significantly attenuated the I/R-induced changes(P＜0.05 or 0.01).Conclusion CS can attenuate the forebrain ischemia-reperfusion injury by reducing histamine and oxidative response.

Objective To determine the risk factors for development of early acute renal failure (ARF) after orthotopic liver transplantation (OLT) in patients with normal renal function.Methods Sixty ASA Ⅱ or Ⅲ patients aged 28-64 yr weighing 35-88 kg undergoing OLT were studied.Their preoperative serum Cr and BUN were within normal range.Early ARF was defined as serum Cr≥132 μmol/L and/or BUN≥18 mmol/L within 24 h after operation.The patients were divided into 2 groups: ARF group and non-ARF group.Arterial blood samples and urine specimens were collected before induction of anesthesia for determination of blood β2-micreglobulin(β2-MG) and urinary β2-MG and N-acetyl-β-D-glucurenidnse (NAG). Factors including preoperative liver function,preoperative blood and urinary β2-MG,the amount of urine output and bank blood infused during operation,MAP during anhepatic and neohepatic phase,the amount of vnsoactive drugs and diuretics used during operation,hypotension and arrbythmia during operation were recorded.The risk factors were identified by logistic regression analysis.Results Logistic analysis indicated that serum β2-MG higher than normal value before operation and persistent hypotensien during operation were closely correlated with development of early ARF after OLT.Conclusion Serum β2-MG higher than the normal value before operation.and persistent hypotension during operation are the risk factors for early ARF after OLT.

Objective To evaluate the cardiac function of the patients with liver cirrhosis before orthotopic liver transplantation(OLT)using Swan-Ganz catheter.Methods Sixty ASAⅡ-Ⅳ patients aged 45-64 yr with liver cirrhosis scheduled for OLT without veno-venous bypass were allocated into 2 groups according to preoperative liver function:compensated group(group C,n=28)and decompensated group(group H,n=32).Anesthesia was induced with midazolam 3-5 mg,fentanyl 0.15-0.2 mg,propofol 1 mg/kg and vecuronium 0.1 mg/ks and maintained with 0.5%-3.0% isoflurane,fentanyl 0.05-0.10 mg and vecuronium 4 mg/h.The patients were mechanically ventilated after tracheal intubation,and P_(ET)CO_2 was maintained at 30-45 mm Hg.Radial artery was cannulated and Swan-Ganz catheter was placed via right internal jugular vein for monitoring of mean arterial pressure(MAP),cardiac output(co),cardiac index(CI),right ventricular ejection fraction(RVEF),mean pulmonary arterial pressure(MPAP),pulmonary arterial wedge pressure(PAWP),right atrial pressure(RAP),right ventricular end-diastolic volume(RVEDV),fight ventricular end-systolic volume(RVESV)and stroke volume index(SVI).Right and left ventricular stroke work index(RVSWI,LVSWI)and systolic and pulmonary vascular resistance(SVR,PVR)were calculated.Results CO,CI,SVI,MPAP,PAWP,RVEDV,RVESV,RVSWI and LVSWI were significantly elevated in group H as compared with group C indicating hyper-hemodynamic state.The SVR and PVR were significantly decreased in group H.There was no significant difference in HR,MAP,RAP and RVEF between the two groups.Conclusion The patients with decompensated liver function before OLT are in a hyper-hemodynamic state.More attention should be paid to perioperative myocardial protection.

OBJECTIVEThis paper aimed to determine the mRNA expression of osteoclast-related factors interleukin-6 (IL-6), interleukin-12 (IL-12) p35, IL-12p40, matrix metalloproteinase-9 (MMP-9), nuclear factor of activated T-cells cytoplasmic 1 (NFATcl), receptor activator of nuclear factor-KB (RANK), and tumor necrosis factor-α (TNF-α) mRNA in murine macrophages infected by a periodontitis patient's own tissue nucleic acid. Another aim was to investigate the effects of a periodontitis patient's own tissue nucleic acid on the differentiation of macrophages into osteoclasts.

METHODSInflammatory periodontal tissue samples of chronic periodontitis patients were taken during periodontal flap surgery, and healthy gingival tissue samples were taken from orthodontic patients during tooth extractions. Total RNA from periodontal tissue was extracted and reversely transcribed into cDNA and then cryo-preserved until further use. First, specific sequence oligodeoxynucleotide MT0I at a concentration of 1 µg · mL⁻¹ was added in murine macrophage RAW264.7, and the cells were incubated for 3 hours. Cells with PBS (1 µg · mL⁻¹) were used as negative controls. The inflammatory periodontal tissue cDNA and healthy periodontal tissue cDNA (1 µg · mL⁻¹) was added subsequently. There were four experimental groups: healthy periodontal tissue cDNA+ RAW264.7, inflammatory periodontal tissue cDNA+RAW264.7, MT01+healthy periodontal tissue cDNA+RAW264.7, and MT01+inflammatory periodontal tissue cDNA+RAW264.7. Real-time quantitative polymerase chain reaction was used to detect the mRNA expression of osteoclast-related factors IL-6, IL-12p35, IL-12p4O, MMP-9, NFATcl, RANK, and TNF-α mRNA after 3, 6, 12, and 24-hours.

RESULTSThe mRNA levels of osteoclast-related factors NFATc1, MMP-9, TNF-a, IL-6, IL-12p40, IL-12p35, and RANK in RAW264.7 were markedly upregulated with the treatment of periodontitis patient's own tissue nucleic acid. However, the mRNA expression of osteoclast-related factors was inhibited by use of an immunosuppressant MT01.

CONCLUSIONThe periodontitis patient's own tissue nucleic acid could promote the differentiation of murine macrophage into osteoclasts.

Animals ; Cell Differentiation ; Cytokines ; metabolism ; Gene Expression ; Gingiva ; Humans ; Interleukin-12 Subunit p40 ; Interleukin-6 ; Macrophages ; Matrix Metalloproteinase 9 ; Mice ; Osteoclasts ; metabolism ; Periodontitis ; RNA, Messenger ; Tumor Necrosis Factor-alpha

Currently three dimensional bio-printing technology has become one of the hot topics for tissue engineering tracheal grafting.Different biomaterials have their own performance advantages in the preparation and regeneration of tracheal scaffolds.It is particularly imperative to seek natural or polymeric materials with excellent profiles of printability, structural stability and biocompatibility to enable neo-cartilage formation, neo-epithelialization and neo-vascularization of tissue engineering trachea grafting.This review summarized the shortcomings and challenges of classifying and applying materials for three dimensional bio-printing tissue engineering trachea, aiming to provide new rationales for researches and applications of tissue engineering tracheal grafting.

BACKGROUND:For the replacement treatment of long-segment tracheal defects,although tissue engineering research has made some progress in recent years,it is still not perfect,and one of the biggest difficulties is that the hemodynamic reconstruction of the tracheal replacement cannot be achieved rapidly. OBJECTIVE:To preliminarily explore the potential of polycaprolactone scaffolds modified with exosome-loaded hydrogels to construct a rapidly vascularized tracheal substitute. METHODS:Exosomes were extracted from bone marrow mesenchymal stem cells of SD rats.After preparation of hyaluronic acid methacrylate solution,the exosome solution was mixed with hyaluronic acid methacrylate solution at a volume ratio of 1:1.Hyaluronic acid methacrylate hydrogels loaded with exosomes were prepared under ultraviolet irradiation for 5 minutes.The degradation of exosome-unloaded hydrogels and the controlled release of exosome-loaded hydrogels were detected.Polycaprolactone scaffolds were prepared by 3D printing.The pure hyaluronic acid methacrylate solution and the exosome-loaded hyaluronic acid methacrylate solution were respectively added to the surface of the scaffold.Hydrogel-modified scaffolds and exosome-modified scaffolds were obtained after ultraviolet irradiation.Thirty SD rats were randomly divided into three groups with 10 rats in each group and subcutaneously implanted with simple scaffolds,hydrogel-modified scaffolds and exosome-modified scaffolds,respectively.At 30 days after surgery,the scaffolds and surrounding tissues of each group were removed.Neovascularization was observed by hematoxylin-eosin staining and Masson staining and the expression of CD31 was detected by immunofluorescence. RESULTS AND CONCLUSION:(1)As time went by,the hydrogel degraded gradually,and the exosomes enclosed in the hydrogel were gradually released,which could be sustained for more than 30 days.The exosome release rate was faster than the degradation rate of the hydrogel itself,and nearly 20%of the exosomes were still not released after 30 days of soaking.(2)Under a scanning electron microscope,the surface of the simple polycaprolactone scaffold was rough.After hydrogel modification,a layer of gel was covered between the pores of the scaffold,and the scaffold surface became smooth and dense.(3)After 30 days of subcutaneous embedding,hematoxylin-eosin staining and Masson staining showed that more neovascularization was observed inside the scaffolds of the exosome-modified scaffold group compared with the hydrogel-modified scaffold group.The hydrogels on the scaffolds of the two groups were not completely degraded.Immunofluorescence staining showed that CD31 expression in the exosome-modified scaffold group was higher than that in the hydrogel-modified scaffold group(P<0.000 1).(4)These results indicate that hyaluronic acid methacrylate hydrogels can be used as controlled-release carriers for exosomes.The 3D-printed polycaprolactone scaffold modified by hyaluronic acid methacrylate hydrogel loaded with exosomes has good biocompatibility and has the potential to promote the formation of neovascularization.