Safety, pharmacokinetics and pharmacodynamics of recombinant human tumour necrosis factor-binding protein-1 (Onercept) injected by intravenous, intramuscular and subcutaneous routes into healthy volunteers

The safety, pharmacokinetics and pharmacodynamics of recombinant human tumour necrosis factor-binding protein-1 (r-hTBP-1, Onercept) were investigated after intravascular and extravascular injection, in three studies in healthy volunteers. Subjects received Onercept as single intravenous doses of 5, 15, 50 and 150 mg, or single IV, IM, SC injection of 50 mg, or six repeated SC injections of 50 mg. Based on vital signs, hematology and blood chemistry, antibodies to study drug and local tolerability, r-hTBP-1 exhibited a remarkably safe profile. There was no evidence of alteration of hepatic oxidative metabolism. Recombinant-hTBP-1 showed linear pharmacokinetics that could be described by a triexponential model, and exhibited an initial half-life of 30 min, an intermediate half-life of 4 hours and a terminal elimination half-life of about 15 hours, although it was prolonged to 21 hours after repeated SC injections. The total clearance was estimated at 4 l/h. The initial (Vc) and steady state (Vss) volumes of distribution were approximately 4 l and 10 l, respectively. Renal clearance was minimal, representing around 2.5% of the total clearance, and remained constant after increasing doses of r-hTBP-1. The absorption was slow and biphasic. The immunoactivity of r-hTBP-1 was closely related to its biological activity, although the assessment was limited to only some of the samples. As anticipated in normal healthy volunteers, the pharmacodynamic response was generally not different from placebo. Total TNF-alpha serum levels increased slightly, 1 hour following IV administration of 50 mg and 150 mg r-hTBP-1. However, no major increase in the active entity levels (free TNF-alpha) was observed. In addition, no TNF-alpha-driven biological response was observed, i.e. C-reactive protein, IL-6 and fibrinogen remained almost constant, as did transferrin and albumin. Its safety profile and pharmacokinetic characteristics make Onercept a candidate drug suitable for antagonising pathologically high levels of TNF-alpha as reported in inflammatory, immune and cardiovascular diseases.     

Cytokine-mediated inflammatory hyperalgesia limited by interleukin-13

The effect of interleukin-13 (IL-13) on hyperalgesic responses to intraplantar (i.pl.) injection of carrageenin, E. coli endotoxin (LPS), bradykinin, tumour necrosis factor a (TNF-alpha), interleukin-1 beta (IL-1 beta), interleukin-8 (IL-8) and prostaglandin E(2) (PGE(2)) was investigated in a model of mechanical hyperalgesia in rats. Also, the cellular source of the IL-13 was investigated. IL-13, administered 30 min before the stimulus, inhibited responses to carrageenin, LPS, bradykinin, and TNF-alpha, but not responses to IL-1 beta, IL-8 and PGE2. IL-13, administered 2 hours before the injection of IL-1b, did not affect the response to IL-1b, whereas IL-13, administered 12 hours or 12 + 2 hours before the IL-1 beta, inhibited the hyperalgesia (- 35%, - 77%, respectively). In murine peritoneal macrophages, IL-13 administered 2 hours before stimulation with LPS, inhibited the production of IL-1 beta (- 67%) and PGE(2) (- 56%). IL-13 administered 12 hours before stimulation with LPS inhibited LPS-stimulated PGE(2) but not IL-1 beta. An anti-IL-13 serum potentiated responses to carrageenin, LPS, bradykinin and TNF-alpha (but not IL-1 beta and IL-8), as well as responses to bradykinin in rats depleted of mast cells with compound 40/80, but not in athymic rats. These data suggest that IL-13, released by lymphocytes, limits inflammatory hyperalgesia by the inhibition of the production TNF-alpha, IL-1 beta, IL-8 and PGs.     

Chinese phlebotomine sandflies of subgenus Adlerius nitzulescu, 1931 (Diptera: Psychodidae) and the identity of Phlebotomus sichuanensis Leng & Yin, 1983. Part I--Taxonomical study and geographical distribution

Four species of Adlerius phlebotomine sandflies have been recorded in China, namely: P. chinensis Newstead, 1916 (Pc), P. fengi Leng & Zhang, 1994; P. longiductus Parrot, 1928 and P. sichuanensis Leng & Yin, 1983 (Ps). Adlerius phlebotomies are the main vectors of visceral leishmaniasis (VL) in China; three of them are acknowledged as VL vectors and P. fengi is considered a potential VL vector for southwestern mountainous region. Different opinion has been raised to the validity of identity of Ps by some investigators from Shanghai and Shanxi who consider Ps to be a large type of Pc instead of an isolate species. The center of controversy is whether Ps is an isolate taxon or a large type of Pc. The present authors have carried out a series of comparative studies for these two flies on: 1 quantitative and qualitative morphological characters of four Chinese Adlerius phlebotomies; and 2. differences in geographical distribution. All specimens of Pc and Ps used in the present study are collected where their holotypes-paratypes were produced--West Mountain, West Suburb, Beijing and Lixian County, Sichuan Province. The results have forcefully proved that Ps is an isolate species instead of a so-called large type Pc according to the concept of species. The clarification of their taxonomical identities is meaningful because both of them are VL vectors in different epidemic areas in China; especially Ps is an important VL vector in high mountainous regions of southwestern China and some extend to the Loess Plateau of northwestern China, where VL still exists and it is also the first Phlebotomine sandfly discovered in Tibet, the locality being near Assam in India (Leng et al. 1990).     

Growth and arginine metabolism of the wine lactic acid bacteria Lactobacillus buchneri and Oenococcus oeni at different pH values and arginine concentrations

During malolactic fermentation (MLF) in grape must and wine, heterofermentative lactic acid bacteria may degrade arginine, leading to the formation of ammonia and citrulline, among other substances. This is of concern because ammonia increases the pH and thus the risk of growth by spoilage bacteria, and citrulline is a precursor to the formation of carcinogenic ethyl carbamate (EC). Arginine metabolism and growth of Lactobacillus buchneri CUC-3 and Oenococcus oeni strains MCW and Lo111 in wine were investigated. In contrast to L. buchneri CUC-3, both oenococci required a higher minimum pH for arginine degradation, and arginine utilization was delayed relative to the degradation of malic acid, the main aim of MLF. This allows the control of pH increase and citrulline formation from arginine metabolism by carrying out MLF with pure oenococcal cultures and inhibiting cell metabolism after malic acid depletion. MLF by arginine-degrading lactobacilli should be discouraged because arginine degradation may lead to the enhanced formation of acids from sugar degradation. A linear relationship was found between arginine degradation and citrulline excretion rates. From this data, strain-specific arginine-to-citrulline conversion ratios were calculated that ranged between 2.2 and 3.9% (wt/wt), and these ratios can be used to estimate the contribution of citrulline to the EC precursor pool from a given amount of initial arginine. Increasing arginine concentrations led to higher rates of growth of L. buchneri CUC-3 but did not increase the growth yield of either oenococcus. These results suggest the use of non-arginine-degrading oenococci for inducing MLF.     

Structural basis of caspase-7 inhibition by XIAP

The inhibitor of apoptosis (IAP) proteins suppress cell death by inhibiting the catalytic activity of caspases. Here we present the crystal structure of caspase-7 in complex with a potent inhibitory fragment from XIAP at 2.45 A resolution. An 18-residue XIAP peptide binds the catalytic groove of caspase-7, making extensive contacts to the residues that are essential for its catalytic activity. Strikingly, despite a reversal of relative orientation, a subset of interactions between caspase-7 and XIAP closely resemble those between caspase-7 and its tetrapeptide inhibitor DEVD-CHO. Our biochemical and structural analyses reveal that the BIR domains are dispensable for the inhibition of caspase-3 and -7. This study provides a structural basis for the design of the next-generation caspase inhibitors.     

Agouti-related protein is a mediator of diabetic hyperphagia

To explore the role of agouti-related protein (AGRP) in diabetic hyperphagia changes in hypothalamic AGRP mRNA levels were examined in diabetic rats. Rats rendered diabetic by streptozotocin displayed marked hyperglycemia (blood glucose 456.0+/-8.4 mg/dl versus 71.8+/-1.9 mg/dl) and hyperphagia (36.9+/-1.0 g/day versus 22.0+/-0.4 g/day), that was associated with a 286.6+/-4.4% increase in hypothalamic AGRP mRNA and a 178.9+/-13.5% increase in hypothalamic NPY mRNA. Insulin treatment of diabetic rats partially corrected blood glucose (147.4+/-13.1 mg/dl) and ameliorated hyperphagia (26.6+/-2.0 g/day). Insulin replacement was also associated with a return of hypothalamic AGRP mRNA (111.7+/-8.3% of controls) and NPY mRNA (125.0+/-8.9% of controls) from the elevated levels that were observed in untreated diabetic rats. In contrast to insulin treated rats, sodium orthovanadate treated diabetic rats remained significantly hyperglycemic (361.5+/-12.5 mg/dl). However, despite their persistent hyperglycemia, orthovanadate treated diabetic rats were still observed to have a significant reduction of hypothalamic AGRP mRNA (138.7+/-11.4%) and NPY mRNA (129.9+/-9.8%). Simultaneous measurement of serum leptin revealed suppressed levels in both untreated diabetic (0.5+/-0.1 ng/ml) and sodium orthovanadate treated rats (0.5+/-0.1 ng/ml) compared to non-diabetic controls (2.1+/-0.1 ng/ml). These data indicate that AGRP is a mediator of diabetic hyperhpagia and suggest that insulin can directly influence hypothalamic AGRP and NPY mRNA expression.     

Cytoplasmic expression of ribozyme in zebrafish using a T7 autogene system

A cytoplasmic ribozyme expression system, based on codelivery of a ribozyme vector, a T7 autogene vector, and T7 RNA polymerase (RNAP), has been developed and used to generate a specific phenotype in zebrafish by targeting a no tail (ntl) mRNA. The expression of the no tail ribozyme sequence is under the control of a tandem of two promoters: The T7 promoter and an adenoviral va 1 (pol III) promoter. The coinjection of the ribozyme vector pT7vaRz, the T7 autogene vector pT7T7, and the T7 RNAP resulted in rapid synthesis of the ribozyme against the ntl mRNA in the cytoplasm of the injected zebrafish embryos, generating no tail phenotypes in up to 10-20% of the injected embryos. The phenotypic change rates have been found to be related to the concentrations of the plasmid vectors and T7 RNAP injected and to the ratios of the three injected components. This cytoplasmic ribozyme expression system may be useful for efficiently targeting other mRNA and for various biomedical applications. These potential applications may include rapid identification of biological functions of novel genes from zebrafish and humans based on partial gene sequence information and gene therapy of genetic and acquired diseases.     

Cloning and characterization of full-length human ribosomal protein L15 cDNA which was overexpressed in esophageal cancer

The aim of this investigation was trying to identify the genes differentially expressed in esophageal cancer. By combining suppression subtractive hybridization (SSH) with reverse Northern high density blots, a gene named EC45 was obtained, which dramatically overexpressed in 70% esophageal cancer (18/26). EC45 was mapped to 3p12-3p11.2 by radiation hybrid mapping (RH mapping). The putative full length EC45 cDNA (1987 bp) was identified by cDNA libraries screening of esophageal cancer. EC45 encoded 204 amino acids, and it shared a 100% similarity with ribosomal protein L15 (635 bp, mRNA) in ORF, but no similarity in 5' UTR or 3' UTR. Northern blot panel of multiple adult human normal tissues showed EC45 distributed in almost normal tissues tested. All these data suggested that EC45, encoding ribosomal protein L15 and overexpressing in esophageal cancer might play a possible role in carcinogenesis of esophagus.     

脑内芳香化酶表达的定位、调控及意义

芳香化酶催化雄激素转化为雌激素,在脑内其表达主要见于下丘脑与边缘系统的神经元内,星形胶质细胞可能也表达芳香化酶。芳香化酶基因表达是由多个组织特异性的启动子驱动的。脑内雌激素的有效浓度取决于脑局部芳香化酶的表达水平,由此产生的雌激素能调节突触发生和树突棘密度、神经营养因子和／或其受体的表达,保护脑细胞免受包括β－淀粉样蛋白在内的多种神经毒素的影响,并可显著改善老年性痴呆（AD）导致的学习和记忆下降及认知缺陷。