BACKGROUND:Colagen hydrogel provides good matrix support for hepatocyte growth and tissue reconstruction, and the colagen-based engineered tissue is easy to merge the growth and form integrated tissue. OBJECTIVE:To improve the thickness of engineered hepatic tissue by dissociating hepatocytes/colagen hydrogel composite into smal hepatic units that accumulate in the subcutaneous cavity. METHODS:Freshly isolated hepatocytes from rats were mixed with colagen hydrogel to establish hepatocytes/colagen hydrogel composite. The hepatocytes/colagen hydrogel composite was dissociated into smal hepatic units after being cured. The undissociated hepatocytes/colagen hydrogel composite was taken as a control. Six Spraque-Dawley rats were enroled. Three of them were subjected to a two-thirds partial hepatectomy to induce liver regeneration. Dissociated and undissociated hepatocytes/colagen hydrogel composites were implanted into the bilateral inguinal subcutaneous cavity. Dissociated and undissociated hepatocytes/colagen hydrogel composites were implanted into the bilateral inguinal subcutaneous cavity of the other three rats. At the 7th day after transplantation, engineered hepatic tissue formation was evaluated using hematoxylin-eosin staining, immunohistochemical staining and India ink perfusion methods. RESULTS AND CONCLUSION:The grafts in these two groups al formed vascular engineered hepatic tissue in the subcutaneous cavity, but after the smal hepatic units merged, a large piece of vascular engineered hepatic tissue formed. The hepatic tissue thickness was up to 4 mm. The whole piece of implanted liver grafts only formed smal pieces of hepatic tissues, with only several layers of cels. Immunohistochemistry staining confirmed that the hepatocytes in vascular engineered hepatic tissue had the characteristics and functions of natural hepatocytes. Partial hepatectomy experiment showed that engineered hepatic tissue had the ability to respond to regenerative stimulus of partial hepatectomy. These results show that dissociating the hepatocytes/colagen hydrogel grafts into smal units that accumlate in the subcutaneous cavity can increase the thickness of the engineered hepatic tissue.

Opioid receptors have drawn highly attention to scientists since they were founded in the 1990s.As a member of G protein-coupled receptor family,opioid peptides are the endogenous ligands.It is well known to us that the basic structure consists of extracellular amino residues,seven transmembrane region and the hydroxyl residues of the cell.In recent years,the progress of science laid the foundation for further studies on the function of delta receptor.Aberrant expression of delta opioid receptor in a variety of tumors,and it plays an important role of the occurrence and development of tumors.This review describes the recent research advances on delta opioid receptor and its association with hepatocellular carcinoma.

Objective To restore the incisal angle defect of anterior upper teeth with partial cov-erage porcelain veneer, and evaluate the clinical performance of the restoration. Methods A total of 12 patients were included, and 14 anterior upper teeth with small incisal angle defect were involved in this study, after tooth reduction of 2 mm wider than the defect of every teeth, 14 partial coverage IPS-Empress Ⅱ veneers were made and binded with Variolink Ⅱ adhesive system. During the observation period of 36-48 months after insertion, prosthodontic results were evaluated, using the CDA quality e-valuation system, and marginal integrity, anatomic form, surface and color of the veneers, and sec-ondary caries were examined. Results During the period of 36-48 observation, all of the 14 restora-tions were rated satisfactory. Conclusions With strict control of indications, the partial coverage porcelain veneer could function satisfactorily as an alternative restoration for small incisal defect of an-terior upper teeth.

Vaccination has been proved to be the most effective strategy to prevent the Corona Virus Disease 2019 (COVID-19). The mRNA vaccine based on nano drug delivery system (NDDS) - lipid nanoparticles (LNP) has been widely used because of its high effectiveness and safety. Although there have been reports of severe allergic reactions caused by mRNA-LNP vaccines, the mechanism and components of anaphylaxis have not been completely clarified yet. This review focuses on two mRNA-LNP vaccines, BNT162b2 and mRNA-1273. After summarizing the structural characteristics, potential allergens, possible allergic reaction mechanism, and pharmacokinetics of mRNA and LNP in vivo, this article then reviews the evaluation methods for patients with allergic history, as well as the regulations of different countries and regions on people who should not be vaccinated, in order to promote more safe injection of vaccines. LNP has become a recognized highly customizable nucleic acid delivery vector, which not only shows its value in mRNA vaccines, but also has great potential in treating rare diseases, cancers and other broad fields in the future. At the moment when mRNA-LNP vaccines open a new era of nano medicine, it is expected to provide some inspiration for safety research in the process of research, development and evaluation of more nano delivery drugs, and promote more nano drugs successfully to market.

Abstract? AIM: To analysis the relation of severity of rhegmatogenous retinal detachment with the levels of amino acids and vascular endothelial growth factor ( VEGF) in the serum and in subretinal fluid.? METHODS: Forty -eight patients ( 52 eyes ) with rhegmatogenous retinal detachment treated in our hospital were selected.According to the degree of retinal detachment, patients were divided into <1/2 quadrant group, 1/2-3/4 quadrant group and>3/4 quadrant group. Fifty-five healthy objects for physical examination in our hospital were selected as the control group, to compare the differences of amino acids and VEGF levels in the serum.Correlation analysis on VEGF levels and amino acids in the serum and in subretinal fluid among patients with different grades of rhegmatogenous retinal detachment was conducted.? RESULTS: In patients with rhegmatogenous retinal detachment, the tryptophan in serum was 28.59±4.46mg/L, phenylalanine 8.95 ±2.55mg/L, methionine 8.15 ±2.17mg/L, valine 28.62 ±5.29mg/L, histidine 18.96 ±1.85mg/L and VEGF 589.92 ±185.34μg/L, which were higher than those in the control group, and the difference was statistically significant(P<0.05).The levels of phenylalanine was 9.85 ±1.21mg/L, histidine 20.63 ±2.07mg/L and VEGF 718.69 ± 283.34μg/L in the subretinal fluid of>3/4 quadrant group, which were significantly higher than those in the <1/2 quadrant group and 1/2-3/4 quadrant group ( P<0.05). VEGF in the subretinal fluid of VEGF in the rhegmatogenous retinal detachment group were positively correlated with phenylalanine (r=0.542, P<0.001), and histidine (r=0.782, P<0.001).?CONCLUSION: The levels of amino acids and VEGF in the subretinal fluid of patients with rhegmatogenous retinal detachment was higher than those in normals and increased with the severity of retinal detachment.

Objective:To study the effects of Tongxinluo,a traditional Chinese medicine,on the proliferation of peripheral blood-derived endothelial progenitor cells(EPCs)in vitro.Methods:The Tongxinluo solution was prepared through ultrasonication according to the pervious literature.The mononuclear cells(MNCs)were isolated from the peripheral blood with Ficoll by density gradient centrifugation.MNCs were suspended in Medium 199 containing 20% fetal blood serum(FBS)and vascular endothelial growth factor(VEGF).After cultured for 7 d,the attached cells were characterized by Di-LDL uptaking and FITC-lectin binding by laser confocal microscope,and further identified through detection of CD34 and CD133 expression by flow cytometry.Then the cultured EPCs were incubated with Tongxinluo at a series of concentrations(0,50,100,200,500, 750,1000?g/ml)for different durations(0,6,12,24 and 36 h).The cell morphology was observed and cell proliferation was determined by MTT assay.Results:Incubation with different concentrations of Tongxinluo increased the proliferative ability of EPCs.Tongxinluo at 500?g/ml had the most prominent effect on proliferation and the effect increased as time went by and reached peak at 36 h(growth rate 54.18%,P

Objective To probe into the clinical curative effect of laparoscopic high ligation of spermatic vein in the treatment of critical varicocele.Methods The clinical data of the 26 eases of laparoscopic high ligation of apermatic vein in the treatment of critical varicocde were reviewed and analyzed in the last two years in this hospi- tal.Results All the 26 cases had been conducted smoothly with the operation time 25～50min,an average of(28?3)min.After 3～24 months being followed-up,all the symptoms and signs disappeared with no relapse and testicle a- trophy.Eight wives of the patients who had been operated on got pregnant.Conclusion With soon recovery and small wound,it was safe to adopt laparoscopic high ligation of spermatic vein in the treatment of critical varicocele, especially for critical two-sided varicocde.

Objective To explore the operative main point and clinical effects of laparoscopic treatment for hepatic cyst. Methods Between August 2006 and April 2009, Forty-eight cases of laparoscopic treatment for hepatic cyst were performed, and the data were analyzed retrospectively. Of these treatments, there were laparoscopic fenestration (46 cases) and laparoscopic anatomical resection of left hepatic lobe (2 cases). Of the patients, there were solitary cyst (41 cases) and multiple cyst (7 cases). Results Fortyeight cases all performed laparoscopic treatment successfully. There were no converting to open operation, no biliary leakage and no bleeding. Except for resection of left hepatic lobe, the operating time was 30 -96 minutes (mean, 45 minutes), the intraoperative blood loss was 10 -90 mL (mean, 26 mL) and the postoperative hospital stay was 3 - 9 days (mean, 5 days). All the 48 patients were followed up for 6 to 36 months (mean, 32 months), 2 cases were found recurrence. Conclusions Affluent experience and proper standard of operation are key points for avoiding recurrence and complication in laparoscopic treatment for hepatic cyst. Laparoscopic treatment for hepatic cyst is safe, characterized by less pain and rapid recovery.

Objective To determine the independent risk factors for sepsis in patients with large area burns.Methods The study enrolled 307 patients with large area burns treated from June 2014 to June 2015.Related variables included age,gender,visit time,emergency eschar open,burn index,tangential excision of eschar during shock stage,delayed resuscitation during shock stage,oxygen pressure(PaO2),carbon dioxide pressure (PaCO2),assisted ventilation mode,mechanical ventilation time,inhalation injury,prophylactic tracheotomy,continuous lactic acid rise,refractory hypernatremia,heart-lung disease history,and diabetes history.Correlation of the variables with the incidence of sepsis was observed.Independent predictors of sepsis in patients with large burns were differentiated using the Logistic regression analysis.Results Delayed resuscitation during shock period (OR =1.747,95％ CI 1.822-7.431,P ＜ 0.05),continuous lactic acid rise (OR =1.758,95％ CI 1.137-4.002,P ＜ 0.05),refractory hypernatremia (OR =2.985,95％ CI 1.074-6.782,P ＜ 0.05),moderate and severe inhalation injury(OR =14.764,95％ CI 0.892-47.323,P ＜ 0.05) and burn index (OR =5.017,95％ CI 1.075-23.572,P ＜ 0.05) were found be independently associated with sepsis in patients with large burns.Conclusions These independent risk factors for sepsis in large area burn patients deserve more attention.Early and timely treatment measures may reduce the incidence of sepsis.

Objective To study the endogenous glucocorticoid on rat femoral head microenvironment of 11 hydroxysteroid dehydrogenase expression ,and to discuss the influence of combined with femoral head pathological changes of the corresponding mechanism .Methods Sixty SD rats were divided into control group ,1‐month group ,3‐months group ,each 20 rats in group .1‐month group and 3‐months group inject cortisone acetate in the abdominal cavity intraperitoneal for 1‐month or 3‐months each .Im‐munohistochemical ,immunofluorescence ,Real‐time qPCR ,HE staining were employed in this study .Results From immunohisto‐chemical ,immunofluorescence ,Real‐time qPCR ,the 11 hydroxysteroid dehydrogenase content of 1‐month group and 3‐months group were higher than that of the control group(P<0 .05) .From HE staining we detected 1‐month group in the bone marrow cavity in‐creased in fat cells ,3‐months group subchondral trabecular bone density decreased ,compared with the control group(P< 0 .05) . Conclusion Supplement of corticosterone could promote rat femoral head microenvironment 11 hydroxysteroid dehydrogenase ex‐pression and subchondral trabecular bone density decrease .