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Objective: In order to preserve more volatile components of celery and reduce its moisture content. Methods: A hot-air coupled microwave drying system based on aroma detection was designed. An electronic nose （PEN3） was applied to detect volatile components, assisted with GC-MS to measure the specific content of volatile components. Based on constant temperature drying （50, 60, 70 and 80 ℃）, sensor 7 and 9 were chosen for subsequent combined control. Results: Comparing with constant temperature drying, the combined control drying using volatile compounds detection could retain more volatile substances, and a good balance had been achieved between the quality of the dried product and the drying rate. The drying time of combined control was 67 min, closing to constant temperature drying at 70 ℃ （63 min）. Meanwhile, optima color difference （16.313±1.745） and sensory evaluation （28.9） were obtained under combined control drying. Conclusion: Microwave coupled hot-air drying control of celery stalks based on volatile compounds detection could be applied to produce high-flavor celery stalks.

Four different drying methods, namely, air drying (AD), microwave-assisted vacuum drying (MWVD), coupled microwave–hot air drying (MWAD), and freeze drying (FD), were studied, in terms of drying time, color, reducing sugar content, shrinkage, microstructure, and sensory evaluation. The drying rate of MWVD and MWAD were notably faster than that of AD and FD. The highest reducing sugar content was observed in MWAD, followed by MWVD. No significant differences were observed in reducing sugar between air-dried and freeze-dried products. FD had the best color and shrinkage among the other drying methods. The color and shrinkage of MWVD drying is close to the fresh litchis and much better than hot air and MWAD. Scanning electron microscopy (SEM) images showed that the MWVD and FD litchis have a porous structure, whereas AD and MWAD litchis have a compact structure. The sensory evaluation suggests that peeled litchis dried by the four studied drying methods are of a quality that is accepted by consumers. [ABSTRACT FROM PUBLISHER]

Aim: To investigate which surgical techniques and perioperative regimens yielded the best survival rates for diabetic rats undergoing gastric bypass., Methods: We performed Roux-en-Y gastric bypass with reserved gastric volume, a procedure in which gastrointestinal continuity was reestablished while excluding the entire duodenum and proximal jejunal loop. We observed the procedural success rate, long-term survival, and histopathological sequelae associated with a number of technical modifications. These included: use of anatomical markers to precisely identify Treitz's ligament; careful dissection along surgical planes; careful attention to the choice of regional transection sites; reconstruction using full-thickness anastomoses; use of a minimally invasive procedure with prohemostatic pretreatment and hemorrhage control; prevention of hypothermic damage; reduction in the length of the procedure; and accelerated surgical recovery using fast-track surgical modalities such as perioperative permissive underfeeding and goal-directed volume therapy., Results: The series of modifications we adopted reduced operation time from 110.02 ± 12.34 min to 78.39 ± 7.26 min (P < 0.01), and the procedural success rate increased from 43.3% (13/30) to 90% (18/20) (P < 0.01), with a long-term survival of 83.3% (15/18) (P < 0.01)., Conclusion: Using a number of fast-track and damage control surgical techniques, we have successfully established a stable model of gastric bypass in diabetic rats.

Background: The treatment of hypoparathyroidism (HPT) is still a difficult clinical problem, which necessitates a new therapy. Gene therapy of HPT has been valuable, but how to improve the gene transfer efficiency and expression stability is a problem. This study was designed to optimize the gene therapy of HPT with hematopoietic stem cells (HSCs) recombined with the parathyroid hormone (PTH) gene., Methods: The human PTH gene was amplified by polymerase chain reaction (PCR) from pcDNA3.1-PTH vectors and inserted into murine stem cell virus (MSCV) vectors with double enzyme digestion (EcoRI and XhoI). The recombinant vectors were transfected into PA317 packaging cell lines by the lipofectin method and screened by G418 selective medium. The condensed recombinant retroviruses were extracted and used to infect HSCs, which were injected into mice suffering from HPT. The change of symptoms and serum levels of PTH and calcium in each group of mice were investigated., Results: The human PTH gene was inserted into MSCV vectors successfully and the titres were up to 2 x 10(7) colony forming unit (CFU)/ml in condensed retroviral solution. The secretion of PTH reached 15 ng.10(-6).cell(-1) per 48 hours. The wild type viruses were not detected via PCR amplification, so they were safe for use. The mice suffering from HPT recovered quickly and the serum levels of calcium and PTH remained normal for about three months after the HSCs recombined with PTH were injected into them. The therapeutic effect of this method was better than simple recombinant retroviruses injection., Conclusions: The recombinant retroviral vectors MSCV-PTH and the high-titre condensed retroviral solution recombined with the PTH gene are obtained. The recombinant retroviral solution could infect HSCs at a high rate of efficiency. The infected HSCs could cure HPT in mice. This method has provided theoretical evidence for the clinical gene therapy of HPT.

Objective: To study the survival rate and secretory function of islet cells in rats under condition of three-dimensional microgravity., Methods: Isolated islet cells were assigned to flask-cultured or bioreactor-cultured. Survival rate of islets cultured for days 3, 7, 14 in stationary flasks or microgravity bioreactors was measured by AO-PI double-staining. Cultured islets were identified by dithizone (DTZ) staining, and insulin contents of different culture liquids were measured by radioimmunoassay., Results: Pancreatic islets stained nacarat with DTZ were easily visualized. When islet cells were cultured for 7 days and 14 days, survival rate of bioreactor-cultured islets was (0.9000 +/- 0.0107)% and 0.8038% +/- 0.0092% and higher than flask-cultured islets (P < 0.01). Insulin level of bioreactor-cultured islets is (70.875 +/- 0.31) m micro /L on the cultured 7 days while flask-cultured islets is (41.246 +/- 0.35) m micro /L. There was statistically significant difference of insulin production between the two groups (P < 0.01). Bioreactor-cultured islet contents were higher than flask-cultured on the cultured 14, 21 and 30 days (P < 0.01)., Conclusions: Islet cells survival rate and secretory function revealed that bioreactor-cultured islets functioned better compared with flask-cultured islets.

Objective: To investigate the relation between serum level of interleukin-8 (IL-8), nitrogen monoxide (NO) and Helicobacter pylori (HP) infection, as well as the possible molecular mechanism of HP infection causing the imbalance of apoptosis and proliferation in gastric epithelial cells, which may lead to oncogenesis in stomach., Methods: Serum IL-8 level was detected with enzyme-linked immunosorbent assay (ELISA). Serum NO was detected with chrome reduction method using plated copper., Results: Serum level of IL-8 were 22.50 +/- 1.87 pg/ml in the normal tissue, 34.99 +/- 7.89 pg/ml in superficial gastritis, 65.27 +/- 10.60 pg/ml in atrophic gastritis and 94.84 +/- 11.09 pg/ml in gastric cancer (P < 0.01). Serum level of NO in the atrophic gastritis group (39.93 +/- 5.43 micromol/L) was significantly higher than that in the gastric cancer group (37.02 +/- 4.13 micromol/L) (P < 0.05). The differences in the other groups were not significant. IL-8 and NO levels in the HP(+) group were significantly higher than those in the HP(-) group (77.30 +/- 20.92 pg/ml vs 39.16 +/- 14.40 pg/ml, P < 0.01; 39.77 +/- 5.57 micromol/L vs 35.35 +/- 5.24 micromol/L, P < 0.01). Serum levels of IL-8 and NO in the cytotoxin-associated gene A protein (CagA)(+)HP group were significantly higher than those in the CagA(-)HP group (83.45 +/- 16.92 pg/ml vs 66.24 +/- 23.21 pg/ml, P < 0.01; 40.97 +/- 4.59 micromol/L vs 37.62 +/- 6.58 micromol/L, P < 0.05). Serum levels of IL-8 and NO showed positive correlation between superficial gastritis and atrophic gastritis groups (r = 0.881, r = 0.995), whereas no correlation was found in the normal or gastric cancer groups., Conclusion: Serum levels of IL-8 and NO are correlated with CagA(+)HP strain infection. Combined detection of serum level of IL-8, NO and HP-CagA will contribute to the early diagnosis of precancerous lesion in the stomach.