Synthesis of [3H] vardenafil,Levitra®, using a new labeling technique

Tritium was introduced into the new orally active, selective phosphodiesterase type V (PDE V) inhibitor vardenafil (Levitra^®), by reduction of a suitable amide precursor with freshly prepared lithium aluminum tritide. A specific activity of 52.7 Ci/mmol (1.95 TBq/mmol) was achieved. In order to overcome the usual technical difficulties during the preparation of complex tritides a new and easy labeling technique which has considerable potential for various tritia‐tion procedures, was developed. Copyright © 2003 John Wiley & Sons, Ltd.     

Differential generation of class I H-2D- versus H-2K-restricted cytotoxicity against a demyelinating virus following central nervous system infection

Despite the fact that both H-2K and D molecules are up-regulated in the central nervous system (CNS) following Theiler's murine encephalomyelitis virus (TMEV) infection, resistance in this virus model of multiple sclerosis maps exclusively to D. To address this paradox, we examined the ability of the K and D molecules to present viral antigens to cytotoxic T lymphocytes (CTL). Whereas no virus-specific CTL were detected in the CNS of susceptible B10.Q and B10.S mice 7 days post-infection, D-restricted CTL were identified readily in the CNS of resistant B10 animals. There was no evidence of K-restricted CTL in the CNS of B10 mice at day 7 post-infection. The presence of both K- and D-restricted virus-specific CTL in the spleen of immunized B10 mice demonstrates that the exclusive use of D molecules by CTL in the CNS of mice 7 days post-infection is not due to the inability of the K molecules to present viral peptides to lymphocytes. We conclude that the prominent role of the D locus in determining resistance or susceptibility to TMEV-induced demyelination is determined by factors governing the regulation of the immune response, and not by the presence or absence of CTL precursors capable of recognizing viral peptides presented by the K and D antigen-presenting molecules, or by differences in the ability of the K and D molecules to present viral peptides.     

轻稀土与联吡啶和菲罗啉三元配合物的合成与表征

合成了稀土（Ｌｎ）与２，２－联吡啶（Ｌ１）、１，１０－菲罗啉（Ｌ２）的三元固态配合物。通过元素分析、ＩＲ谱、ＴＧＡ谱和摩尔电导等对该系列配合物进行了表征，实测结果与通式ＬｎＬ１Ｌ２Ｃｌ３·３Ｈ２Ｏ符合较好。抗菌试验表明，该系列配合物有较强的广谱抗菌作用。     

Epitope Context and Reshaping of Activated T Helper Cell Repertoire

In recent years, a growing interest in the study of peptide antigenicity in relation to the role of flanking sequences and protein topology in processing, presentation, and recognition has been observed. However, the information available on the antigenicity of recombinant fusion proteins and their effect on the selection of antigen receptor repertoires is limited. To analyze the role of molecular topology of T epitopes in a system relevant to human pathology, we have used the bacterially expressed Schistosoma japonicum glutathione S transferase (GST) to construct recombinant antigens containing HIV-1 derived T cell determinants, and human T cell clones specific for these determinants. We found that antigenicity of a given GST—peptide combination was not the same when T cells and antigen presenting cells from different individuals were tested. Our results show that differences in processing and presentation of chimeric proteins are not dictated by the use of diverse restriction elements. We also found that the context in which an antigenic peptide is delivered affects the recruited repertoire as defined according to T cell receptor Vβ usage and fine specificities of selected T cells.     

Surface coat of sheep pulmonary intravascular macrophages: Reconstitution,and implication of a glycosyl-phosphatidylinositol anchor

Background: Pulmonary intravascular macrophages (PIMs) of sheep have a globular surface coat that facilitates endocytosis of tracer particles and Escherichia coli lipopolysaccharide, and is disrupted by the heparin and Brefeldin A treatments. The present study investigated the in vivo dynamics of the coat globules following heparin-mediated removal, and the mechanism of globule organization on the plasma membrane of PIMs in vitro. Methods: Sheep were administered heparin at a dose of 50 IU/kg body weight IV, and euthanised at 30 min, 3, 6, 12, 48, and 120 hr (n = 2 for each treatment) after the treatment. Control sheep (n = 2) were injected with normal saline solution. The tissues were processed for an ultrastructural examination and acid phosphatase (ACPase) cytochemistry. Heparintreated lungs were subjected to morphometric analysis of the coat globules. Lung tissues from normal sheep (n = 2) were incubated with phosphatidylinositol-specific-phospholipase C (PIPLC; 2 IU/ml PBS) in vitro for 30 and 75 min. Results: Heparin study: The ultrastructural and morphometric data showed that the coat globules were removed at 30 min and reconstituted within 48 hr of the treatment. The PIMs showed priminent Golgi complexes associated with secretory vesicles, microtubules, and centriole between 3–12 hr of heparin treatment. Acid phosphatase cytochemistry also demonstrated secretory activity in the Golgi complexes of PIMs during the coat reconstitution. PIPLC study: The coat globules of PIMs were removed in a time-dependent mode by the PIPLC treatment without damage to other cell organelles. Conclusions: This study demonstrates a time-dependent reconstitution of the coat of PIMs in conjunction with secretory activity following heparinmediated removal, probably through sequenstration of the globules from blood. This ability is of functional significance as the coat mediates particle endocytosis by the PIMs. The results also suggest the presence of a glycosyl-phosphatidylinositol (GPI) anchor in tethering of globules on the plasma membrane of PIMs to offer a structural basis for their integrity in pulmonary vascular flow. © 1995 Wiley-Liss, Inc.     

尿中糖胺多糖总量的测定方法

本文采用原子吸收的方法测定样品中糖胺多糖的含量。此法的灵敏度为0.102μg/ml,样品中铜检出值的变异系数为9％,平均回收率为103％,因此认为本方法的灵敏度、精密度和准确度都较高。此外,样品中存在的铜和葡萄糖对本实验均无干扰作用。     

HFE codon 63/282 (H63D/C282Y) dimorphism in German patients with genetic hemochromatosis

Abstract: Genetic hemochromatosis (GH) is closely associated with genes of the major histocompatibility complex (MHC) on chromosome 6. Recently, a candidate gene for GH, with structural similarities to MHC class I genes, designated HLA-H and presently named HFE, has been cloned. The HFE gene is localized telomeric to the MHC and several reports have indicated that the HFE gene is mutated in GH patients. In the present study we have analyzed the relationship of HFE gene variants and disease manifestation in GH patients and family members. Fifty-seven patients with GH, 73 family members and 153 healthy blood donors were studied for the amino acid dimorphism at codon 63 (His63Asp=H63D) and codon 282 (Cys282Tyr= C282Y) of the HFE gene. The codon 63 and 282 dimorphism were defined by PCR amplification of genomic DNA samples and restriction enzyme digestion using RsaI/SnaBI for C282Y and Bcll/Mbo 1 for H63D. Ferritin, transferrin serum levels and total iron-binding capacity were determined prior to therapeutic intervention. The Tyr-282 substitution occurred in 53 (93%) of patients compared with 8 (5.2%) of controls (OR=169, P >0.0001). Fifty-one (90%) patients were Tyr-282 homozygous. In contrast, the Asp-63 substitution was present in 5 (8.8%) of the patients compared with 34 (22%) of controls (OR=0.39, P =NS) with none of the patients being homozygous. In Tyr-282 homozygous GH patients serum ferritin levels, transferrin saturation, liver iron and liver iron index were elevated significantly compared to Tyr-282-negative patients, whereas no difference was observed between Tyr/Cys-282 heterozygous and Tyr-282-negative patients.     

C3d及荷C3d免疫复合物的测定与意义

用抗人Ｃ３和抗人ＩｇＧγ球蛋白组分作固相反应物，建立了检测补体活化片段Ｃ３ｄ及荷Ｃ３ｄ－ＩＣ的ＥＬＩＳＡ法，并对临床各类疾病患者血清Ｃ３ｄ和Ｃ３ｄ－ＩＣ的水平进行了测定，结果表明：慢性肾炎，ＳＬＥ，慢性乙肝及肺炎患者血清Ｃ３ｄ总体水平均较对照组显著增高，分别有５８．５％～７２．２％的病人Ｃ３ｄ含量高于正常上限（Ｐ〈０．０１），且该类病人亦有较高的Ｃ３ｄ－ＩＣ阳性检出率（肺炎患者例外）本项研究中，Ｃ     

Is the effect of acute hyperglycaemia on interdigestive antroduodenal motility and small-bowel transit mediated by insulin?

Acute hyperglycaemia inhibits antroduodenal motility. In non-diabetic subjects this inhibitory effect may result from reactive endogenous hyperinsulinaemia. Therefore, we investigated the effects of hyperinsulinaemia during both hyperglycaemia and euglycaemia on interdigestive antroduodenal motility (perfusion manometry) and duodenocaecal transit time (DCTT; lactulose breath-H₂ test). Six healthy volunteers (age 20–26 years) were studied for 240 min on three separate occasions in random order during: (a) i.v. saline (control); (b) acute hyperglycaemic hyperinsulinaemia (HG) with plasma glucose at 15 mmol L^?1; and (c) euglycaemic hyperinsulinaemia (HI) with plasma insulin at 80 mU L^?1 and glucose at 4–5 mmol L^?1. Results: DCTT was significantly (P < 0.05) prolonged during HG (158 ± 23 min) compared with control (95 ± 25 min), whereas HI had no effect (100 ± 17 min). Mean duration of complete migrating motor complex (MMC) cycles was significantly (P < 0.05) reduced during HG (63 ± 9 min) compared with control (103 ± 15 min) and HI (105 ± 16 min), which resulted from a significantly (P < 0.05) shorter duration of phase II. Antral motility was significantly (P < 0.05) reduced during both HI (20 ± 8 contractions 240 min^?1) and HG (9 ± 5) compared with control (43 ± 7). It is concluded that in healthy subjects hyperglycaemia prolongs DCTT, increases duodenal MMC cycle frequency and inhibits antral motility. Hyperinsulinaemia reduces antral motor activity but has no effect on interdigestive duodenal motility or DCTT. Thus, other factors, apart from insulin, mediate the inhibitory effect of hyperglycaemia on interdigestive intestinal motility and transit.     

Splenic nonenhancement at computed tomography: A sign of the hypoperfusion complex

When splenic nonenhancement is seen at computed tomography, one should look for signs of vascular pedicle injury; if injury to the vascular pedicle is not present, nonenhancement of the spleen could be secondary to severe vasoconstriction and may be considered an additional sign of the hypoperfusion complex. The presence of splenic nonenhancement may also help differentiate the hypoperfusion complex from other types of bowel injury.