Parecoxib prevents nucleus pulposus cells apoptosis by suppressing endoplasmic reticulum stress.

OBJECTIVE: Intervertebral disc degeneration (IVDD) is the main cause of spine diseases, and apoptosis of nucleus pulposus (NP) cells is an important risk factor for the degeneration of intervertebral discs. Endoplasmic reticulum (ER) stress is involved in multiple apoptosis processes. This study investigated whether the specific COX-2 inhibitor parecoxib can inhibit NP cell apoptosis induced by ER stress. PATIENTS AND METHODS: Human NP cells were isolated from the disc tissue collected from IVDD patients. We used IL-1ß to establish an NP cell degenerated model. Degenerated levels were detected by the analysis of cell viability, collagen II, collagen X, aggrecan, TNF-α, IL-6, and MMP-13 expression. ER stress status was examined by GRP78 and CHOP expression. Apoptosis level was mainly indicated by the positive apoptotic cells and caspase-12 expression. CHOP-plasmid transfection was performed to overexpress the CHOP protein level. RESULTS: IL-1ß could induce the decrease of viability, collagen Ⅱ, aggrecan, but an increase of collagen X, TNF-α, IL-6, and MMP-13 in NP cells, as well as the upregulation of GRP78/PERK/caspase-12 and apoptosis level, which could be inhibited by parecoxib. Parecoxib could also suppress CHOP caused by COX-2 upregulation and apoptosis in NP cells. CONCLUSIONS: Parecoxib is a safe and efficient COX-2 inhibitor to NP cells, which could prevent NP cells apoptosis by suppressing ER stress.

Glutathione S-transferase A1 - a sensitive marker of alcoholic injury on primary hepatocytes.

The primary hepatocytes were extracted and purified from mice through improved Seglen two-step perfusion method. Ethanol-induced injury hepatocytes model in mice was used to investigate the importance of glutathione S-transferase A1 (GSTA1) in hepatocytes injury by comparison with other indicators, such as alanine aminotransferase, aspartate aminotransferase, malondialdehyde, glutathione and superoxide dismutase. The release of GSTA1 was demonstrated to be an earlier and more sensitive indicator of hepatocytes injury than other indicators. Significant increases in GSTA1 were detected at 2 h after ethanol exposure, while other indicators were undetected at this time. A markedly difference in other indicators were observed at 6 and 8 h. The release of GSTA1 was significantly increased at a concentration of 50 mmol/L ethanol, the lowest exposure concentration than that in other indicators. In contrast, other indicators release was not statistically significant until concentrations of 75 mmol/L and 100 mmol/L ethanol. These results suggest that GSTA1 can be detected at the early stage of low concentration ethanol exposure and that GSTA1 is more sensitive and reliable marker in ethanol-induced hepatic injury.

Desalination of brackish groundwater by direct contact membrane distillation.

The direct contact membrane distillation (DCMD) applied for desalination of brackish groundwater with self-made polyvinylidene fluoride (PVDF) membranes was presented in the paper. The PVDF membrane exhibited high rejection of non-volatile inorganic salt solutes and a maximum permeate flux 24.5 kg m(-2) h(-1) was obtained with feed temperature at 70 degrees C. The DCMD experimental results indicated that the feed concentration had no significant influence on the permeate flux and the rejection of solute. When natural groundwater was used directly as the feed, the precipitation of CaCO(3) would be formed and clog the hollow fibre inlets with gradual concentration of the feed, which resulted in a rapid decline of the module efficiency. The negative influence of scaling could be eliminated by acidification of the feed. Finally, a 250 h DCMD continuous desalination experiment of acidified groundwater with the concentration factor at constant 4.0 was carried out. The permeate flux kept stable and the permeate conductivity was less than 7.0 microS cm(-1) during this process. Furthermore, there was no deposit observed on the membrane surface. All of these demonstrated that DCMD could be efficiently used for production of high-quality potable water from brackish groundwater with water recovery as high as 75%.

Molecular cloning and expression of human interleukin-6 in insect cells.

670-bp hIL-6 cDNA fragments have been amplified by polymerase chain reaction (PCR) using recombinant plasmid pBMIL-6A as templates and two synthetic oligonucleotides containing the optimized translation initiation sequence and restriction sites suitable for cloning as primers. The amplified IL-6 cDNA fragments have then been recombined with a non-fusion expression baculovirus vector pVL1393. The resultant recombinant plasmid pVL. IL-6 together with wtAcMNPV DNAs were transferred into cultured lepidopteran insect cells (Sf9) by calcium phosphate coprecipitation procedure. The recombinant baculoviruses were formed by homologous recombination in vivo between pVL. IL-6 and wtAcMNPV DNAs, screened for plaque assay, and identified by means of dot blotting hybridization. The expressed rhIL-6 was secreted into the culture medium, and its bioactivity was measured through half-maximum H-TdR incorporation into IL-6-dependent cells 7TD1. As a result, the supernatant collected from recombinant baculovirus rAc. IL-6-infected Sf9 cells showed IL-6 activity of 10(6) U/mL. The expression level of rhIL-6 of the supernatant determined by IL-6 ELISA quantitation kit was 1 microgram/mL.

Reconstruction of esophagus with whole stomach through esophageal bed after resection of the upper esophageal carcinoma. A report of 160 cases.

From September 1985 to December 1992, 160 cases of reconstruction of the esophagus with the whole stomach through the esophageal bed after resection of the upper esophageal carcinoma were performed with neither operative mortality nor intrathoracic complications. The leakage rate of the cervical anastomosis with Gambee's single layer method was 1.2%. The main steps of the operative procedure consisted of: (1) making a right thoracotomy for dissecting and removing the entire thoracic esophagus; (2) laparotomy for mobilizing the whole stomach, constricting it to tube shape and doing a pyloroplasty; and (3) pulling up the mobilized tube-like stomach through the posterior mediastinal space (i.e. the esophageal bed) out of the left neck incision and then the esophagogastrostomy with Gambee's single layer anastomosis was performed.

[Clinical studies of intra-thoracic stomach function in patients after esophagectomy and reconstruction by whole stomach].

We usually use the stomach to hung up into the chest and to the neck for esophago-gastrostomy in the patients of esophageal cancer. We had studied the intrathoracic stomach function in patients after esophagectomy with isotope 99m Tc labelled 717-resin semisolid meal for scintigram. We measured the gastric emptying time (GET) and fund the GET1/2 was no difference between the preoperative group and contrast group (P > 0.05). The study indicated that GET1/2 was faster obviously in postoperative patients with pyloroplasty than without pyloroplasty (P < 0.01). It was proved that to perform pyloroplasty with esophagostomy should be used routinely for preventing the pylorospasm, dilatation of the intrathoracic stomach and gastroesophageal reflux. At the same time, we found fasting serum gastrin (FSG) was increased (P < 0.01) in patients after esophagectomy than before, but basal acid output (BAO) decreased. It indicated that vagotomy caused the BAO decreasing and PH increasing. There were some relations between high level of FSG and postoperative diarrhea.

[Application of Gambee's single layer anastomosis in cervical esophagogastrostomy].

To decrease the incidence of postoperative leakage, we used the Gambee's method of single layer anastomosis in cervical esophagogastrostomy for carcinoma of the hypopharynx and superior segment of the esophagus. Since December 1985, this method has been used in 76 cases resulting leakage in only 2 cases (2.6%). The technique of Gambee's single layer anastomosis is described in this paper. It is very important to keep the mucosa and submucosa layers in close contact to promote healing of the anastomosis. It is concluded that Gambee's single layer anastomosis is a good and safe operative technique for cervical esophagogastrostomy.