Thioredoxin fusion/HIV-1 protease coexpression system for production of soluble human IL6 in E. coli cytoplasm

In this paper, thioredoxin (TRX) fusion expression system has been modified to produce soluble human IL6 (hIL6) without TRX moiety in E. coli cytoplasm. A novel TRX gene fusion vector was developed that contained at the 3'-end of TRX gene a short DNA sequences encoding a linker peptide '-GSGSGVSQNYPIVQHHHHHH-', serving not only as a specific HIV-1 protease site but also providing six contiguous histidine (His) residues to foreign proteins. The cDNA for hIL6 was cloned into this vector resulting in plasmid pTRX@HISIL6. The cDNA for the HIV-1 protease has been cloned into another compatible plasmid pHMM2, resulting in plasmid pHMM2-PR. Both plasmids were transformed into E. coli strain GI724, and when induced for expression of both proteins, the correct processing of TRX@HISIL6 was obtained, producing hIL6 with His6-tag at the N terminus named HISIL6. A fraction of HISIL6 was found in soluble form and could be purified to homogeneity by Ni-NTA Superflow and ion-exchange chromatography. The biological activity of purified HISIL6 was measured by MTT method in an IL-6-dependent cell line 7TD1 to be 2.1 x 10(8) unit/mg.     

强化管理 开创国家电网安全生产新局面

介绍2003年度国家电网公司安全生产情况和措施，分析电网安全生产中存在的问题，提出2004年国家电网公司安全生产工作目标和措施。     

Transgenic mice expressing human ApoB95 and ApoB97. Evidence that sequences within the carboxyl-terminal portion of human apoB100 are important for the assembly of lipoprotein

The structural features of apolipoprotein (apo) B that are important for its covalent linkage to apo(a) to form lipoprotein(a) (Lp(a)) are incompletely understood. Although apoB100 cysteine 4326 is required for the disulfide linkage with apo(a), other structural features, aside from a single free cysteine residue, must be important for apoB's initial interaction with apo(a) and for facilitating the formation of the disulfide bond. To determine if sequences carboxyl-terminal to cysteine 4326 affect the efficiency of Lp(a) formation, we used "pop-in, pop-out" gene targeting in a human apoB yeast artificial chromosome to introduce nonsense mutations into exon 29 of the apoB gene. The mutant yeast artificial chromosomes, which coded for the truncated versions of human apoB, apoB95, and apoB97, were then used to express these mutant forms of apoB in transgenic mice. As judged by in vitro assays of Lp(a) formation, apoB95 (4330 amino acids) formed a small amount of Lp(a) but did so slowly. In contrast, apoB97 (4397 amino acids) formed Lp(a) rapidly, although not quite as rapidly as the full-length apoB100 (4536 amino acids). These results were supported by an analysis of double-transgenic mice expressing both human apo(a) and either apoB95 or apoB97. In mice expressing both apoB95 and apo(a), there was only a trace amount of Lp(a) in the plasma, and most of the apo(a) was free, whereas in mice expressing both apoB97 and apo(a), virtually all of the apo(a) was bound to apoB97 in the form of Lp(a). These results show that sequences carboxyl-terminal to apoB95 (amino acids 4331-4536) are not absolutely required for Lp(a) formation, but this segment of the apoB molecule, particularly residues 4331-4397, is necessary for the efficient assembly of Lp(a).     

Gingival recession and exposure of barrier membrane: effect on guided tissue regeneration of Class II furcation defects

The purpose of the present study was to evaluate the effect of barrier membrane exposure on the success of guided tissue regeneration in Class II furcation defects. Twenty-six subjects with mandibular Class II furcation defects received initial periodontal therapy followed by guided tissue regeneration surgery. The membrane was placed and the flaps were repositioned so that the membrane was totally submerged. Membranes were removed 4 to 6 weeks later, at which time the extent of their exposure was recorded. An overall improvement in all clinical parameters was observed for all subjects 1 year after surgery. Half of the patients had experienced no membrane exposure, while the other 13 subjects had experienced mild to pronounced exposure; both groups showed similar improvement in all clinical and surgical parameters. In light of the comparable results obtained in exposed sites, and the anatomic difficulties sometimes encountered in covering a membrane completely, in some of these cases the membrane may be left only partially submerged. This approach will allow for tighter occlusal "seal" of the tooth-membrane interface and preservation of the keratinized gingiva.     

Effect of moditen-depot therapy on the duration and quality of remissions in schizophrenia patients

The authors studied the effectiveness of out-patient treatment by Moditen-Deppt of 128 schizophrenic patients. A comparison of the previous remissions appearing during usual pharmacotherapy and remissions seen during Moditen-Depot treatment depicted statistically significant differences, indicating a distinct prevention of exacerbations due to this preparation, an increase in the duration and improved quality of remissions. Such improved remissions were expressed in lesser severity, in a decrease of psychopathological disturbances, changes qualified as a "mollification of a defect" and an improvement of some socio-clinical indices.     

Acute renal failure in patients with acute pancreatitis

We describe five patients with acute pancreatitis in whom acute renal failure developed in the absence of hypotension. Pancreatitis was diagnosed clinically, with mean serum and urinary amylase levels of 766 +/- 197 (SE) and 2,378 +/- 572 units/100 ml, respectively. Acute renal failure developed within 24 hours after admission in all patients. It was manifested by oliguria, elevated levels of serum creatinine (mean, 6.9 +/- 1.1 mg/100 ml) and BUN (105 +/-28 mg/100 ml); a urinary sodium level of 72.0 +/- 6.6 mEq/liter; and isosmotic urine (355 +/- 31 mOsm/liter). The mean uric acid level was 18.6 +/- 1.6 mg/100 ml. Blood pressure was recorded frequently, and the lowest mean diastolic pressure was 96 +/- 6 mm Hg. The duration of the oliguric phase of acute renal failure was 8.2 +/- 1.7 days, and all patients recovered from both the acute pancreatitis and acute renal failure. In summary, acute pancreatitis, per se, can precipitate acute renal failure. It occurs early in the course of the pancreatitis, and extreme hyperuricemia is frequent finding that does not adversely affect the recovery of renal function.     

The use of multivariable standard curves in the radioimmunoassay of testosterone and 5alpha-dihydrotestosterone

Threshold fluctuations are divided into short-term and long-term effects applying statistical methods. Sixteen normal and pathological visual fields were analysed in order to obtain values for the short-term, long-term and total fluctuations. Special attention is paid to fortuitous variations between the results obtained at successive examinations. Finally the concept of spatial correlations is introduced.