饮食性缺铜、缺锌对小鼠细胞因子产生的影响

３周龄小鼠饲用６周缺铜饮食后，出现胸腺萎缩、肝脏肿大以及明显的缺铜指征，包括血清Ｃｐ活性、肝Ｃｕ含量、ＣＣＯ和Ｃｕ，Ｚｎ－ＳＯＤ活性明显下降。缺钢小鼠产生的ＴＮＦ－α、ＩＬ－１和ＩＬ－６水平明显低于正常组小鼠。小鼠饲予７周缺锌饮食后，出现明显脱毛，虽然肝Ｚｎ含量降低不明显，但ＴＮＦ－α、ＩＬ－１和ＩＬ－６活性明显降低，说明上述细胞因子是小鼠缺锌的敏感指征之一。本文结果显示正常Ｃｕ、Ｚｎ水平对ＴＮＦ－α、ＩＬ－１和ＩＬ－６产生的重要性，并提示这些细胞因子的改变可能是缺铜、缺锌引起的免疫功能损害的细胞、分子学机理之一。     

Further evidence for the alternative pathway of trehalose synthesis linked to maltose utilization in Saccharomyces

Summary Yeast strains bearing a deficiency in trehalose-6-phosphate synthase activity are unable to accumulate trehalose on any carbon source unless they contain one of the MAL genes. If the gene is inducible then synthesis of trehalose occurs specifically during growth on maltose when the MAL gene is constitutive then trehalose accumulation can also be seen when cells are grown on glucose. Different systems for trehalose synthesis were suggested: one of them would require the UDPG-linked trehalose synthase whereas the second would utilize an alternative pathway. We proposed a mechanism by which the gene-product of a MAL gene would serve as a common positive regulator for the expression of the genes coding for maltose permease, -glucosidase and some component of the trehalose accumulation system. In order to elucidate this novel pathway a strain lacking UDPG-linked trehalose synthase activity and harboring a defect in maltose uptake was constructed. Excessive maltose uptake resulted in accumulation of intracellular maltose, and twice as much trehalose as in a control strain. Partial inhibition of hexokinase by xylose affected the ratio between internal maltose and trehalose and significantly reduced glycogen synthesis. Sodium fluoride also blocked glycogen synthesis but allowed for trehalose accumulation. Moreover, a mutant which lacks hexokinase I and II was unable to accumulate trehalose when grown on glucose in spite of the presence of a constitutive MAL2 gene. These results suggest that trehalose synthesis would require G-6-P formation derived from maltose. Such a deviation would allow for slowing down the glycolytic flux which, in turn, would favour efficient maltose utilization. Therefore, trehalose synthesis during growth in media containing glucose serves as an additional parameter for assessing constitutivity of MAL genes.     

Mutation detection in the alpha-1 antitrypsin gene (PI) using denaturing gradient gel electrophoresis

A method for mutation detection in the alpha-1 antitrypsin gene (protease inhibitor 1; PI) has been developed using denaturing gradient gel electrophoresis of PCR amplified gene fragments. Using this experimental approach, all common phenotypes and mutations could be detected. Denaturing gradient gel electrophoresis (DGGE) was compared with standard isoelectric focusing (IEF) in 20 potential alpha1-antitrypsin deficient patients and their relatives. The genotype determined by DGGE was found to be more reliable in some cases than IEF, which is essential for a proper diagnosis of alpha-1 antitrypsin malfunctioning.     

δ-aminolevulinic acid dehydrase (porphobilinogen synthase) in two families with inherited enzyme deficiency

The inheritance of a deficient delta-aminolevulinic acid dehydrase (ALA-D; synonym: porphobilinogen synthase; EC 4.2.1.24) was studied in blood samples of two families over three generations. The propositus in each family was a young male acute hepatic porphyria patient with an almost complete ALA-D deficiency in the homozygous state (ALA-D activity less than 2% of controls). Heterozygotes are clinically non-affected (mean ALA-D 36% of controls). The mode of transmission could be traced by enzyme activity and electrophoretic polymorphism studies. Heterozygotes are detected by the demonstration of enzyme activity in the gel. The notation D was used for the gene expressing the defective enzyme. The "phenotype" D-1 was observed in six, the "phenotype" D-2 in three of all heterozygotes studied. These results are compatible with a single normal allele in heterozygotes responsible for enzyme activity. Quantitative assays and the segregation pattern in both families suggest a 3-allele-system for the inheritance of ALA-D deficiency.     

Chondral separation in the trochlear groove - a definite clinical entity

Four patients with unusual femoro-patellar chondral defects are presented. We were unable to find their particular lesion described adequately in the literature. The patients all gave a history of relatively minor non-contact injury and presented with anterior knee pain and persistent swelling. The main features on clinical examination were moderate effusion and marked patello-femoral crepitus. Plain X-rays of the knee were unhelpful. At arthroscopy large full thickness chondral defects were seen on the femoral side of the patello-femoral articulation at the site of patellar contact with the knee in about 60° of flexion. The synovium was found to be prolific and vascular. Multiple 1.6-mm drill holes were made in the defect and chondral debris was washed out. Two patients underwent associated lateral patellar release. When a clear cut mechanical patello-femoral disorder presents unexpectedly with associated effusion and a normal radiograph, we suggest that arthroscopy be advised with particular attention to the femoral trochlea.     

Mucopolysaccharidosis type IIIC (Sanfilippo): early clinical presentation in a large Turkish pedigree

Two sisters from a large consanguineous Turkish family with Sanfilippo C disease presented within the first 2 years of life. They had coarse facial features, organomegaly and discrete radiological signs of dysostosis multiplex. Urinary glycosaminoglycan excretion was elevated, heparan sulfate being the major component. The uptake of radioactive sulfate into fibroblasts from both patients was abnormal. A deficiency of acetylCoA: alpha-glucosamine transferase was demonstrated in fibroblasts from one patient. To our knowledge, this is the first report of the disease presenting in early infancy.     

Cross-reactivity between IgE-binding proteins from Anisakis German cockroach, and chironomids

Pascual CY, Crespo JF, San Martin S, Ornia N, Ortega N, Caballero T, Munoz-Pereira M, Martin-Estaban M. Cross-reactivity between IgE-binding proteins from Anisakis German cockroach, and chironomids. Anisakis simplex larvae parasitize animals used as seafood and can produce a specific immune response in man. The ingestion of seafood contaminated with stage three of A. simplex larvae can induce a specific IgE response with clinical symptoms, usually urticaria, even if the fish is cooked before ingestion and the invasive infestation power destroyed by heating. Our preliminary studies showed a strong association of A. simplex sensitization with Ascaris lumbricoides, Daphnia chironomid spp., Atlantic shrimp ‘Pandalus borealis’ and German cockroach ‘Blattella germanica’. We conducted the cross-reactivity study with cockroach, a ubiquitous insect, and Chironomidae ‘red mosquito larvae’, a work-related allergen, without any possibility of Anisakis contamination. Serum samples were collected from 60 pediatric patients, with serum specific IgE to A. simplex. Both specific-IgE and immunoblot-inhibition studies, with a serum pool from 18 patients, were performed to determine whether the association of sensitizations to nematodes and arthropods was due to immunologic cross-reactivity. In addition, serum samples from 21 of 60 patients who showed also sensitization to German cockroach were used for individual immunoblot studies. In the serum pool, dose-dependent inhibition of B. germanica and Chironomus spp. was observed after preincubation with the A. simplex extract. Immunoblot of Anisakis inhibited with Chironomus and German cockroach, yielded a partial blot inhibition but mainly on bands below 41 kDa. Blot inhibition of German cockroach and Chironomus with Anisakis was dose related. The band patterns in individual blots were heterogeneous, but most of them had bands of 30–43 kDa. None of these sera recognized allergens in the 14–kDa area. In our study, CAP-inhibition and immunoblot-inhibition analysis of Anisakis showed that several IgE-binding components could be shared by the three allergens.     

Synergistic convergence of microbiota-specific systemic IgG and secretory IgA

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