Survivin expression in breast cancer predicts clinical outcome and is associated with HER2, VEGF, urokinase plasminogen activator and PAI-1

BACKGROUND

Survivin, a novel inhibitor of apoptosis, is one of the most cancer-specific proteins identified to date. In this study we (a) evaluated the association between survivin and HER2, vascular endothelial growth factor (VEGF) and uPA/PAI-1 expression and (b) defined its effect on clinical outcome in a large breast cancer patient cohort.

PATIENTS AND METHODS

Survivin expression was measured by ELISA in primary breast cancer tissue extracts from 420 patients with long-term clinical follow-up.

RESULTS

Survivin was detected in 378 (90%) of the 420 primary breast cancer cases. Increased survivin levels were significantly associated with high nuclear grade (P < 0.0001), negative hormone receptor status (P = 0.0028), HER2 overexpression (P = 0.0094), VEGF expression (P < 0.0001), high uPA (P = 0.0002) and PAI-1 levels (P = 0.0002). Using the 25th percentile (1.4 ng/mg) as a cut-off point, patients expressing elevated survivin had a significantly worse disease-free survival (DFS: P = 0.0007, RR 1.97) and overall survival (OS: P = 0.0009, RR 2.11) compared with patients expressing lower levels of survivin. In multivariate analysis, this prognostic value of survivin was independent of both traditional and novel clinicopathologic factors for both DFS (P = 0.0076, RR 1.72) and OS (P = 0.0155, RR 1.76).

CONCLUSIONS

The independent prognostic relevance of survivin, when combined with previous data from model systems implicating survivin in the inhibition of apoptosis, suggests that survivin may be a suitable target for future therapeutic strategies.

Cloning and expression of L-asparaginase gene in Escherichia coli

The L-asparaginase (ASN) from Escherichia coli AS1.357 was cloned as a DNA fragment generated using polymerase chain reaction technology and primers derived from conserved regions of published ASN gene sequences. Recombinant plasmid pASN containing ASN gene and expression vector pBV220 was transformed in different E. coli host strains. The activity and expression level of ASN in the engineering strains could reach 228 IU/mL of culture fluid and about 50% of the total soluble cell protein respectively, more than 40-fold the enzyme activity of the wild strain. The recombinant plasmid in E. coli AS1.357 remained stable after 72 h of cultivation and 5 h of heat induction without selective pressure. The ASN gene of E. coli AS1.357 was sequenced and had high homology compared to the reported data.

[The upconversion "characteristic saturation phenomenon" of ErYb:ZBLAN glass excited by 966 nm diode laser]

This paper researches the upconversion luminescence of Er:ZBLAN and ErYb:ZBLAN glasses excited by 966 nm diode laser. It is found that there is a new kind of "characteristic saturation phenomenon". It is that the log-log plot's slope of upconversion luminescence intensity upon laser power of ErYb:ZBLAN glass is decreased clearly than that of Er:ZBLAN, and both of their log-log plots are rather good straight line. This upconversion mechanism is a new kind of "diffusion-transfer" mechanism, that is energy diffusion among Yb3+ ions sequential followed by energy transfer between Er(3+)-Yb3+ ions. The "characteristic saturation phenomenon" is just resulted from energy diffusion.

[Study on the structure of epimerides of cycloclausenamide]

AIM

To study the structures of the epimerides of cycloclausenamide.

METHODS

The structures of compound I, extracted from Clausena lansium (Lour.) Skeels, and synthesized compound III were determined by single crystal X-ray diffraction analysis. The stereo-structures of compound II and IV were also built up through Tripos force field based on crystal structures of compound I and III.

RESULTS

The molecular formula and molecular weight were found to be C18H17O2N and 279.34 respectively. Compound I crystallized in monoclinic system, space group P2(1) with a = 0.5928(1), b = 1.5014(1), c = 1.6190(1) nm, V = 1.4410(3) nm3, Z = 4, Dx = 1.288 g.cm-3, Rf = 0.075, Rw = 0.073(w = 1/sigma 2|F|), S = 3.983; compound III crystallized in triclinic system, space group P1 with a = 0.5667(1), b = 1.2934(1), c = 2.1119 (1) nm, alpha = 102.17(1), beta = 90.25(1), gamma = 102.65(2) degrees, V = 1.4770(5) nm3, Z = 4, Dx = 1.224 g.cm-3, Rf = 0.047, Rw = 0.051(w = 1/sigma 2|F|), S = 0.467.

CONCLUSION

These results showed that compound I and III both are cycloclausenamide except that the directions of the phenyl group on C6 are different. Cycloclausenamide can form 4 pairs of epimerides but the directions of the phenyl group does not affect their energy in free state.

[The effect of ischemic preconditioning on adenosine phosphate content after spinal cord ischemia in rabbits]

AIM

To study the effect of ischemic preconditioning (IP) on adenosine phosphate content after spinal cord ischemia in rabbits.

METHODS

We established a lumbar spinal cord ischemia model by inflating the balloon of a 4F Swan-Ganz catheter positioned in the abdominal aorta of the rabbits. All rabbits were divided into sham-operated group, ischemic group and IP group. Adenosine phosphate content in spinal cord of all rabbits was determined at 4 hours, 2 days and 5 days after spinal cord ischemia by using reverse phase HPLC.

RESULTS

ATP content in lumbar spinal cord of rabbits in ischemic group was markedly reduced (P < 0.01 vs sham-operated group). But in IP group, it was obviously elevated at each time point compared with ischemic group (P < 0.01).

CONCLUSION

IP can significantly elevated ATP content in postischemic lumbar spinal cord in rabbits. This may be one of the mechanisms that IP can protect spinal cord from ischemic injury.

[An effect enhancement mechanism of up-conversion luminescence--up-conversion sensitization]

The research of frequency up-conversion has been developed greatly in recent ten years. In order to achieve its applications, it needs to enhance the up-conversion efficiency further greatly, which is the core problem of up-conversion. Because of the specialty of Yb3+ ion energy level, Yb3+ can greatly enhance up-conversion luminescence of co-doped rare earth ion activator through energy transfer. Meanwhile it may not cause the obvious fluorescence quenching. Thus it is very significance to investigate up-conversion sensitization which Yb3+ ion acts as a sensitizer. It is more important that it is quite urgent to combine up-conversion efficiency and material property to develop up-conversion. This paper reviews the proposing and developing process of up-conversion sensitization. The achievement of up-conversion sensitization field especial the originate fruit in indirect up-conversion sensitization obtained by China are introduce emphatically.

Genomic structure and chromosomal localization of the gene encoding TRAX, a Translin-associated factor X

The TRAX gene encodes a Translin-associated 33-kDa protein partner, TRAX. The TRAX protein has extensive amino acid homology with Translin, and contains bipartite nuclear targeting sequences, suggesting a possible role in the selective nuclear transport of Translin lacking any nuclear targeting motifs. In the present study, genomic clones of the human TRAX gene were isolated to determine the complete genomic organization. The genomic structure of the human TRAX gene was similar to that of the human Translin gene, consisting of six exons and five introns, encompassing approximately 27kb in genomic DNA. Northern blot analysis revealed a predominant transcript of approximately 2.7kb, and its distribution in various tissues was like that of Translin. Chromosomal mapping by fluorescence in situ hybridization (FISH) analysis allowed localization of the TRAX gene to human chromosome lq41.

In vivo biological effects of various forms of thrombopoietin in a murine model of transient pancytopenia

Thrombopoietin (TPO) is the natural regulator of platelet production in the bone marrow of mammals. This cytokine also seems to play an important role in the development of the erythroid lineage when recovering from anemic conditions. Here we study the effects of various TPO molecules on the recovery of hematopoietic lineages in a mouse model of pancytopenia. Based on previous animal experimentation and clinical experience with other hematopoietic cytokines, we found that daily dosing with TPO augmented the recovery of both the megakaryocyte and erythroid lineages in a mouse model of pancytopenia. However, further experiments showed that no benefit was gained by using more than a single dose of recombinant murine (rm)TPO(335) given 24 h after the initiation of the myelosuppressive treatment. This response to a single dose of rmTPO(335) is dose-dependent. However, the response was attenuated when a truncated, short half-life TPO molecule (rmTPO[153]) was used. Increasing the half-life of the molecule with 10 kDa polyethylene glycol (PEG) does not improve the response. Only when larger PEG molecules (20 kDa or 40 kDa) are linked to the rmTPO(153) is the response to single doses restored to the level of the full-length molecule. These data suggest that, unlike our experience with other cytokines, the commitment of progenitors to a megakaryocytic cell line is accomplished by a single short exposure to TPO.

[Determination of Avermectin B1 content by first-order derivative spectrum analysis]

After acquiring the ultraviolet absorption spectrum and its first order derivative spectrum distributions of Avermectin B1 by using UV-2401 PC spectrophotometer and spectrum-measuring system, we found that coordinates of the peak A252.2 and the valley A256.8 are not disturbed by the different forms of preparations. We considered that delta A = A252.2-A256.8 is the reliable ground for quantitative analysis of Avermectin B1 content in order to reduce error. The standard regression equation c = 272.7 delta A-0.161 and the related coefficient r = 0.9996 are obtained through measurements of the standard preparations. Then the Avermectin B1 content and the average recovery rate of different preparations are determined and the result indicates that this method is especially suitable for determining the Avermectin B1 content.

Construction and structural modeling of a single-chain Fv-asparaginase fusion protein resistant to proteolysis

In this study, we construct a fusion protein composed of L-asparaginase (ASNase; from Escherichia coli AS 1.357) and a protective single-chain Fv (scFv), which was selected from a phage-display scFv library from our previous studies. The antibody moiety of the fusion protein was fused to the N-terminus of the enzyme moiety via a linker peptide, (Gly(4)Ser)(6). Recombinant plasmid pET-SLA was constructed to express scFv-ASNase fusion to high levels in E. coli and the expressed product was found to form inclusion bodies. We obtained a soluble fusion protein by refolding and purification. The soluble fusion protein exhibited about 82% of the enzymatic activity of the native ASNase at the same molar concentration, and had a K(m) value similar to that of the native enzyme for the substrate L-asparagine. Importantly, the fusion protein was more stable than native ASNase. In addition: (1) following treatment with trypsin, alpha-chymotrypsin, and rennet, at 37 degrees C for 30 min, scFv-ASNase fusion retained 94.0%, 88.8%, and 84.5% of its original activity, respectively, whereas native ASNase became inactive; and (2) ScFv-ASNase fusion had a much longer in vitro half-life (9 h) in serum than the native enzyme (2 h). The three-dimensional structure of the fusion protein was obtained by modeling with the Homology and Discover modules of the INSIGHT II software package. On the basis of the structural evidence and biochemical properties, we propose that the scFv moiety of the fusion protein may confer ASNase moiety resistance to proteolysis as a result of both steric hindrance and a change in the electrostatic surface of the enzyme.

Receptor-selective variants of human vascular endothelial growth factor. Generation and characterization

Vascular endothelial growth factor (VEGF) is a pleiotropic factor that exerts a multitude of biological effects through its interaction with two receptor tyrosine kinases, fms-like tyrosine kinase (Flt-1) or VEGF receptor 1 and kinase insert domain-containing receptor (KDR) or VEGF receptor 2. Whereas it is commonly accepted that KDR is responsible for the proliferative activities of VEGF, considerable controversy and uncertainty exist about the role of the individual receptors in eliciting many of the other effects. Based on a comprehensive mutational analysis of the receptor-binding site of VEGF, an Flt-1-selective variant was created containing four substitutions from the wild-type protein. This variant bound with wild-type affinity to Flt-1, was at least 470-fold reduced in binding to KDR, and had no activity in cell-based assays measuring autophosphorylation of KDR or proliferation of primary human vascular endothelial cells. Using a competitive phage display strategy, two KDR-selective variants were discovered with three and four changes from wild-type, respectively. Both variants had approximately wild-type affinity for KDR, were about 2000-fold reduced in binding to Flt-1, and showed activity comparable with the wild-type protein in KDR autophosphorylation and endothelial cell proliferation assays. These variants will serve as useful reagents in elucidating the roles of Flt-1 and KDR.

Characterization of l-asparaginase fused with a protective ScFv and the protection mechanism

A fusion protein of the protective scFv linked to the C-terminus of ASNase via (Gly(4)Ser)(6) peptide was constructed. The ASNase-scFv fusion protein expressed in Escherichia coli exists mainly in the form of inclusion bodies, and a small amount of it was soluble. The soluble form was purified by four-step purification and it has been demonstrated that ASNase-scFv fusion exists as a dimer. By assay of the stability against proteolysis, the ASNase-scFv fusion was found to be more stable than native ASNase but less stable than scFv-ASNase fusion. The results of immunological assay indicated that the immunogenicity of the fusion proteins increased while their binding capacity with the anti-ASNase serum decreased by comparison to the native ASNase. Moreover, here the comparison of the basic physical and chemical properties of the ASNase-scFv fusion, scFv-ASNase fusion, and native ASNase is presented. Based on the structural evidence and the biochemical analysis described in this paper, the protection mechanism proposed in our previous study was further supported. The scFv moiety of the fusion protein may confer the ASNase moiety resistance to proteolysis as a result of both steric hindrance such as blocking the cleavage sites of trypsin and a change in the electrostatic potential surface of the enzyme.

Lamina propria lymphocytes, not macrophages, express CCR5 and CXCR4 and are the likely target cell for human immunodeficiency virus type 1 in the intestinal mucosa

Most human immunodeficiency virus type 1 (HIV-1) infections are acquired via mucosal surfaces, and transmitted viruses are nearly always macrophage-tropic, suggesting that mucosal macrophages participate in early HIV-1 infection. Mucosal lymphocytes isolated from normal human intestine expressed CD4 (14,530+/-7970 antibody-binding sites [ABSs]/cell), CCR5 (2730+/-1524 ABSs/cell), and CXCR4 (2507+/-1840 ABSs/cell), but intestinal macrophages, which also expressed CD4 (2959+/-2695 ABSs/cell), displayed no detectable CCR5 or CXCR4 ABS. The absence of CCR5 on intestinal macrophages was not due to expression of the Delta32 deletion allele because matched-blood monocytes expressed CCR5. CCR5(+)CXCR4(+) intestinal lymphocytes supported both R5 (BaL) and X4 (IIIB) HIV-1 replication, whereas the CCR5(-)CXCR4(-) macrophages were not permissive to either isolate or other laboratory isolates (ADA and DJV) and primary isolates (MDR 24 and JOEL). In the intestinal mucosa, lymphocytes, not macrophages, are the likely target cell for R5 (and X4) HIV-1 and are the major source of HIV-1 production during early infection.

Biological parameters of HIV-1 infection in primary intestinal lymphocytes and macrophages

Mucosal surfaces are the portal of entry for most HIV-1 infections and play an important role in disease pathogenesis. To characterize the biological parameters of HIV-1 infection in mucosal cells, we used purified lamina propria lymphocytes and macrophages from normal human small intestine to determine the distribution of the HIV-1 receptor and coreceptors on intestinal mononuclear cells and the permissiveness of these cells to HIV-1 infection. Lamina propria lymphocytes expressed CD4, CCR5, and CXCR4. In contrast, lamina propria macrophages expressed CD4 but not CCR5 or CXCR4. Intestinal lymphocytes supported replication by R5 and X4 isolates of HIV-1, but lamina propria macrophages were permissive to neither. RANTES, macrophage inflammatory protein-1alpha (MIP-1alpha), and MIP-1beta inhibited infection of intestinal lymphocytes by BaL, indicating that R5 infection of the intestinal lymphocytes was mediated by CCR5. Thus, resident lamina propria lymphocytes, not macrophages, are the target mononuclear cell for HIV-1 infection in the intestinal mucosa during early HIV-1 infection.

An association study of polymorphisms in the alpha-antichymotrypsin gene for Alzheimer disease in Han-Chinese

Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and DNA sequencing were employed to screen the coding region of the alpha-antichymotrypsin (AACT) gene in Han-Chinese population for polymorphism possibly associated with Alzheimer's disease (AD). Consequently, seven polymorphic sites including 25A>G, 39G>A, 370C>T, 662T>G, 892C>T, 923T>C and 1332A>G were detected. Of them, the 25A>G was reported previously and the others are all novel. We subsequently focused on the 25A>G and the 39G>A polymorphism that were of interest to us and conducted an association study of them by another scanning of 246 controls that matched the AD patients. Statistic test showed that both genotype (p=0.0378, Fisher's exact, two tailed) and allele frequency (p=0.0382, Fisher's exact, two tailed) of 39G>A are different between AD patients and the controls. As for 25A>G, lain only the heterozygous genotype A/G associates with AD (p=0.0220, chi(2)), but not the A allele frequency (p=0.1141, chi(2)).

[The electroluminescence of organic and polymer thin film materials]

In recent years, researches on electroluminescence (EL) of organic and polymer thin film materials have been made with an outstanding progress, and have attracted much interest because of its large-area, full color, high luminance displays which can be driven with low dc voltage. In this paper, the history of the development on electroluminescence, the devices and the selection of luminescent materials and the electroluminescence principle are introduced briefly.

Selecting and expressing protective single-chain Fv fragment to stabilize L-asparaginase against inactivation by trypsin

Four non-inhibitory specific single-chain Fv (sc Fv) fragments directed against L-asparaginase (ASNase) of Escherichia coli were selected from a synthetic phage-display scFv library. The scFv46 fragment could enhance the resistance of ASNase to trypsin proteolysis, with 70% of the initial ASNase activity present after the ASNase-scFv46 complex had been treated with trypsin for 30 min at 37 degrees C, whereas little residual activity was detected without the scFv46 fragment. The scFv46 gene was cloned to an expression vector pET-21a and expressed at high levels (about 45% of total cell protein) in E. coli BL21 (DE3) as inclusion bodies. The refolded and purified scFv46 fragment was proved to protect ASNase, and the protective effect was further confirmed by SDS/PAGE. It was found that under optimum conditions of molar ratio of scFv to ASNase, incubation time and temperature, the residual activity of the ASNase-scFv46 complex could reach about 78% after treatment with trypsin for 30 min at 37 degrees C. The results demonstrated that scFv fragments prepared by phage-antibody library technology could be used to protect target proteins.

Structural analysis of the gene encoding RP58, a sequence-specific transrepressor associated with heterochromatin

RP58, a sequence-specific transcriptional repressor sharing homology with the POZ domain of a number of zinc-finger proteins, is highly synthesized in brain and localized in condensed chromatin regions, suggesting a role in transcriptional repression in the central nervous system. In the present study, genomic clones of the human rp58 gene were isolated to determine the complete genomic organization. Sequence analyses indicated that the human rp58 gene encoding the functional protein is uninterrupted over its entire 4.2 kb length. Comparison of the human and mouse rp58 genes revealed that they share not only a high homology in the amino acid sequences of their encoded proteins, but also a high degree of structural similarity at the genomic level. RT-PCR analysis also demonstrated the existence of an alternatively spliced form of rp58 similar to the previously reported zinc-finger cDNA, C2H2-171. Chromosomal mapping by fluorescence in situ hybridization analysis allowed localization of the rp58 gene to human chromosome 1q44 ter, a genetic region associated with a number of human malignancies and neurological disorders.

[Culture conditions of engineered strain of L-asparaginase and the recombinant plasmid stability]

The growth curves of engineered strain JM105(pASN) were different in LB and M-3 media. The expression level and activity of L-asparaginase were affected apparently by both biomass and induction time. Glucose repression of production of L-asparaginase was found. The stability of the recombinant plasmid pASN in different host strains and in LB and M-3 media was determined. After cultivation inLB broth and M-3 media at 30 degrees C for more than 50 generations without antibiotic selection, then induced at 42 degrees C for up to 5 h, the engineered strains were proved to be stable, except for DHA alpha (pASN).

[Artificial Neural Network and its application to analytical chemistry]

Artificial Neural Network system(ANNs) was presented involving its theoretical basis, algorithm and performance. Its application to nonlinear calibration, pattern recognition and other related fields in analytical chemistry has been reviewed. 95 references are cited.

[The 1. 54 microm laser and upconversion luminescence of YELPP noncrystalline induced by 969 nm LD laser]

In this paper, the absorption of Er3+, Yb3+ penta-phosphate noncrystalline (YELPP) was measured and the basic spectral parameters were calculated. Adopting the longitudinal-pump method with a domestic diode laser (LD), we achieved CW 1.5 microm chipped laser in China for the first time. The power of 1.5 microm laser was quite stable. The target of 1.5 microm laser reached the international level of early 1990s' in this field. In addition, the up-conversion luminescence was measured under the condition that 1.5 microm laser was either oscillating or not. The relationship between 1.5 microm chipped laser and up-conversion luminescence was analyzed initially.

Mucosal events in the pathogenesis of human immunodeficiency virus type 1 infection

The interaction between human immunodeficiency virus type 1 (HIV-1) and primary mucosal cells isolated from normal human small intestine was investigated. Purified primary intestinal epithelial cells could transport cell-free HIV-1 to mononuclear cells, although the epithelial cells did not support viral replication. An unexpected finding was that primary intestinal macrophages were markedly less permissive to HIV-1 than were blood monocytes. The reduced permissiveness appeared to be due to the near absence of surface CCR5 on resident intestinal macrophages. Surface CCR5 could be up-regulated on the monocytes but not the intestinal macrophages by HIV-1 and gp120. Impaired permissiveness of intestinal macrophages to HIV-1 may play an important role in the low prevalence of HIV-1 mRNA-expressing macrophages in the lamina propria during HIV-1 infection in vivo. Characterization of the biologic properties of HIV-1 transport and infection in primary mucosal cells will be key to elucidating the pivotal role of mucosal surfaces in HIV-1 disease.

Intestinal macrophages display reduced permissiveness to human immunodeficiency virus 1 and decreased surface CCR5

BACKGROUND & AIMS

Because the role of intestinal mononuclear cells in the pathogenesis of human immunodeficiency virus 1 (HIV-1) disease has not been elucidated, we determined the biological properties of HIV-1 infection in primary intestinal macrophages.

METHODS

Mucosal macrophages purified from normal human jejunum were infected with well-characterized macrophage-tropic isolates of HIV-1 (ADA, DJV, and Ba-L).

RESULTS

Productive HIV-1 infection of intestinal macrophages was demonstrated by the release of p24 antigen, the presence of proviral DNA, and zidovudine inhibition of infection. Surprisingly, the titer of virus needed to establish infection of intestinal macrophages was 100-1000-fold higher than that required to infect peripheral blood derived macrophages. This marked reduction in the permissiveness of intestinal macrophages to HIV-1 was not caused by the isolation procedure or differences in CD4 expression. Instead, intestinal macrophages expressed almost no CCR5, the principal coreceptor for macrophage-tropic HIV-1, compared with blood-derived macrophages, although both cell types contained comparable levels of CCR5 messenger RNA. Exposure of blood-derived but not intestinal macrophages to HIV-1 or gp120 led to increased surface expression of CCR5.

CONCLUSIONS

Intestinal macrophages express reduced levels of HIV-1, probably because of impaired permissiveness to HIV-1 entry associated with the near absence of cell surface CCR5.

[Study on the human serums by absorption spectra]

The absorption spectra of normal human and cancer patient serums were measured, and those of human serum after adding some cancer cells were also measured. The results showed some difference in absorbance among the three kinds of serums. Some useful results were obtained.

Gastrointestinal infections in the immunocompromised host

Gastrointestinal infections are a frequent and important complication of immunodeficiency diseases and immunosuppressive therapy. Such infections may be severe, prolonged, or even fatal, whereas the same infections are typically mild and transient in immunocompetent persons. In this regard, the strong association between HIV-induced immunosuppression and the increased prevalence of severe enteric infections is strong evidence of the link between immune function and defense against enteric pathogens. Because gastrointestinal infections in immunocompromised persons are frequently severe and life-threatening, a vigorous approach to the diagnostic evaluation and therapeutic management is advocated by many clinical investigators. In this review, we summarize the important new developments, particularly during the past year, regarding gastrointestinal infections in immunocompromised persons.

Crystal structure of the complex between VEGF and a receptor-blocking peptide

Vascular endothelial growth factor (VEGF) is a specific and potent angiogenic factor and, therefore, a prime therapeutic target for the development of antagonists for the treatment of cancer. As a first step toward this goal, phage display was used to generate peptides that bind to the receptor-binding domain (residues 8-109) of VEGF and compete with receptor [Fairbrother, W. J., Christinger, H. W., Cochran, A. G., Fuh, G., Keenan, C. J., Quan, C., Shriver, S. K., Tom, J. Y. K., Wells, J. A., and Cunningham, B. C. (1999) Biochemistry 38, 17754-17764]. The crystal structure of VEGF in complex with one of these peptides was solved and refined to a resolution of 1.9 A. The 20-mer peptide is unstructured in solution and adopts a largely extended conformation when bound to VEGF. Residues 3-8 form a beta-strand which pairs with strand beta6 of VEGF via six hydrogen bonds. The C-terminal four residues of the peptide point away from the growth factor, consistent with NMR data indicating that these residues are flexible in the complex in solution. In contrast, shortening the N-terminus of the peptide leads to decreased binding affinities. Truncation studies show that the peptide can be reduced to 14 residues with only moderate effect on binding affinity. However, because of the extended conformation and the scarcity of specific side-chain interactions with VEGF, the peptide is not a promising lead for small-molecule development. The interface between the peptide and VEGF contains a subset of the residues recognized by a neutralizing Fab fragment and overlaps partially with the binding site for the Flt-1 receptor. The location of the peptide-binding site and the hydrophilic character of the interactions with VEGF resemble more the binding mode of the Fab fragment than that of the receptor.

Blunted thrombopoietin response to interferon alfa-induced thrombocytopenia during treatment for hepatitis C

Thrombocytopenia is common in advanced-stage liver disease and is partly caused by inadequate thrombopoietin (TPO) production in the failing liver. Treatment of chronic hepatitis C with interferon alfa (IFN-) often induces thrombocytopenia, sometimes even leading to discontinuation of treatment. TPO regulation in response to IFN--induced thrombocytopenia was studied in patients with chronic hepatitis C with and without cirrhosis (Child A). An in vitro culture system with HepG2 cells was used to demonstrate any direct effects of IFN- on TPO mRNA expression, TPO synthesis, or TPO secretion from liver cells. Thrombocyte count was lower (U test: P < .05) in patients with hepatitis C cirrhosis compared with patients with chronic hepatitis C without cirrhosis before IFN therapy, and decreased in both patient groups (Wilcoxon matched-pairs test: P < . 05) on IFN therapy, the median decrease in both groups being comparable (noncirrhotic patients, 35%; cirrhotic patients, 32%; U test: P = .57). TPO levels rose in noncirrhotic patients (Wilcoxon matched-pairs test: P < .05), but not in patients with cirrhosis (noncirrhotic patients' median increase: 43% vs. cirrhotic patients' median decrease: 5%; U test: P < .001). Even in patients without cirrhosis, the increase in TPO levels was relatively small for the decrease in platelet count. No effect of IFN- could be demonstrated on TPO mRNA expression in vitro, but TPO secretion from liver cells was significantly reduced. Lower platelet counts but similar TPO levels in patients with chronic hepatitis C and cirrhosis compared with noncirrhotic patients and a moderate increase in TPO levels in noncirrhotic patients with a missing increase in cirrhotic patients during IFN--induced thrombocytopenia provide further evidence for an impairment of TPO production in patients with cirrhosis and during IFN therapy. Recombinant human TPO could be of value in patients developing severe thrombocytopenia under IFN- therapy.

RP58 associates with condensed chromatin and mediates a sequence-specific transcriptional repression

An approximately 120-amino acid domain present generally at the NH2 termini, termed the POZ domain, is highly conserved in various proteins with zinc finger DNA binding motifs. We have isolated a novel protein sharing homology with the POZ domain of a number of zinc finger proteins, including the human BCL-6 protein. By using a binding site selection technique (CAST), a high affinity binding site of the protein was determined to be (A/C)ACATCTG(G/T)(A/C), containing the E box core sequence motif. The protein was shown to repress transcription from a promoter linked to its target sequences and was hence named RP58 (Repressor Protein with a predicted molecular mass of 58 kDa). Immunogold electron microscopic study revealed that almost all RP58 is localized in condensed chromatin regions. These observations demonstrate for the first time that a protein mediating a sequence-specific transcriptional repression associates with highly condensed chromatin. We suggest that RP58 may be involved in a molecular link between sequence-specific transcriptional repression and the organization of chromosomes in the nucleus.

[Anatomy and operation of agger nasi ethmoidal cells and frontal recess]

To reduce postoperative recurrency of nasal polyps and sinusitis, the anatomy of lateral wall of nasal cavity was studied in body head. It was found that there was a considerable wide area between the anterior attachment of the middle turbinate and the roof of ethmoidal sinus, just where the agger nasi ethmoidal cells and frontal recess lying. And also the medial wall of agger nasi ethmoidal cell is just above the anterior attachment of middle turbinate. In our operations, the bony structure above the anterior attachment of middle turbinate was resected to open the medial wall of agger nasi ethmoidal cells and the frontal recess, the lesions in them was removed carefully to reobtain a well drainage. 15 cases were followed up for 0.5 to 1.5 years and the result was satisfying.

[Indirect sensitized upconversion in Tm3+ and Yb3+ codoped non-crystal pentaphosphate]

We report the blue upconversion luminescence of Tm3+ and Yb3+ codoped non-crystal pentaphosphate pumped by -798nm laser diode. The samples were directly excited to 3F4 level of Tm3+ ion. Two energy transfer processes between Tm3+ and Yb3+ contribute mainly to the population of 1G4 level of Tm3+. Phonon plays an important role in the upconversion process.

[Study on the effect of human herpesvirus 6 on replication of Epstein-Barr virus]

OBJECTIVE

To examine the effect of human herpesvirus 6(HHV-6) on the replication of Epstein-Barr virus (EBV) in cell lines.

METHODS

Both EBV-infected Raji cells and EBV-transformed lymphoblastoid cell lines (LCL) were infected with HHV-6. Immunofluoresence assay (IFA) with monoclonal antibodies (MAb) against HHV-6 was applied to confirm the infection of HHV-6 in the two cell lines. Expression of EBV antigen was examined by IFA using human anti-EBV serum.

RESULTS

Following HHV-6 infection, cytopathic effects (CPE) were observed in Raji cells but not in LCL. HHV-6 were detected in both cell lines by IFA with anti-HHV-6 MAb, but not in controls. EBV antigens were detected by IFA with human serum against EBV in both HHV-6 infected cell lines.

CONCLUSION

Data in this study suggest that HHV-6 promotes the expression of EBV antigen and may contribute to the pathogenesis of nasopharyngeal carcinoma in cooperation with EBV.

Acute exacerbation of autoimmune liver disease associated with hantaviral infection

Hantavirus is known to cause haemorrhagic fever with renal syndrome (HFRS). Although liver dysfunction has been reported in HFRS, hepatic manifestations of hantaviral infection have not been well described. We describe a case of autoimmune cholangitis in which an exacerbation of hepatitis was associated with hantaviral infection. Seroconversion of both IgG- and IgM-class antibodies to hantavirus was noted coincident with acute exacerbation of hepatitis, which was resolved promptly by treatment with corticosteroid. No extrahepatic manifestations were noted. This case suggests that hantavirus may trigger acute exacerbation of autoimmune liver disease without extrahepatic manifestations and that it may cause community-acquired hepatitis.

[Three-dimensional volumetric display--a new application of frequency up-conversion]

This paper discusses the present research situation and the application prospect of 3-D volumetric display technology. The possible usability and science significance of frequency up-conversion in 3-D volumetric display field are also demonstrated systematically. In ZBLAN: Pr, Yb glasses, we primarily demonstrated and achieved a new application of frequency up-conversion three dimensional volumetric display, using the two-frequency up-conversion of the rare earth ions. The efficiency of luminescence of Pr was enhanced much by the energy transfer between Pr and Yb ions.

The effect of anti-CD3-immunotoxin on T lymphocyte function in vitro

Recent advances in the design of immunotoxins (IT) have yielded significant improvements. FN18-CRM9, a construct of anti-CD3 epsilon mAb FN18 and mutated diphtheria toxin CRM9 has exhibited high specificity, low systemic toxicity and unusual efficacy compared to previous iterations of immunotoxins. Others and we have examined this anti-CD3-IT for the purpose of inducing immunological tolerance through selective ablation of T cells in rhesus macaques and have obtained encouraging results. In order to characterize its mode of action, we have examined its effects on peripheral blood and lymph node T cell killing in vitro. We have studied the cytotoxic mechanism induced by this anti-CD3-IT as well as its effects on proliferation, phenotypic changes and cytokine production (IL2, IFN gamma and TNF alpha). The results indicate that anti-CD3-IT was highly specific for T cell killing at doses as low as 1 x 10(6) micrograms/ml and showed a maximal effect at 48 h after exposure. The toxicity was restricted to T cells, as B cells and other bystander cells were spared. This immunotoxin was shown to induce T cell apoptosis, as assessed by TUNEL assay, DNA content and cytotoxicity. Fas expression was upregulated on T cells within 24 h after in vitro exposure to anti-CD3-IT, suggesting an early T cell activation phase prior to T cell death. T cell killing was manifest as an early cell cycle arrest at the G1/S phase transition, which appeared to virtually eliminate the production of cytokines. These findings corroborate the temporal, specificity and quantitative patterns for anti-CD3 immunotoxin administration previously observed in vivo.

Preclinical studies of allograft tolerance in rhesus monkeys: a novel anti-CD3-immunotoxin given peritransplant with donor bone marrow induces operational tolerance to kidney allografts

A major challenge in clinical transplantation today is to design a practical and effective protocol for tolerance induction compatible with cadaver organ transplantation. A preclinical rhesus monkey kidney allograft model using immediate peritransplant anti-CD3 immunotoxin (anti-CD3-IT) and donor bone marrow (DBM) is shown here to induce operational tolerance with prolonged graft survival in the absence of chronic immunosuppressive drugs. Bone marrow harvested from the kidney donor was depleted of mature alloantigen-presenting cells and T cells by removing DR(bright) cells and CD3(bright) cells, respectively. In outbred, major histocompatibility complex-incompatible donor-recipient pairs with high pretransplant mixed lymphocyte response and cytotoxic T lymphocyte precursor activity, four of six allografts survived for periods of 120 days to >1.5 years. Graft acceptance after peritransplant treatment followed robust elimination of both peripheral blood T cells and lymph node T cells. In most recipients given anti-CD3-IT and DBM infusion, anti-donor immunoglobulin G responses were completely inhibited. Microchimerism was observed in all recipients studied, including those not given DBM, but levels of microchimerism did not correlate with graft survival. Anti-CD3-IT induction in combination with modified DBM protocols such as the depletion of mature T cells and DR(bright) antigen-presenting cells may offer new opportunities to improve clinical tolerance protocols beyond those attempted in the clinic to date. Overall, these results with anti-CD3-IT show promise for development of cadaver transplant tolerance induction.

Infection of gastrointestinal tract macrophages by HIV-1

As the largest lymphoid organ and the largest reservoir of macrophages in the body, the gastrointestinal tract mucosa is probably the largest organ reservoir of macrophages infected with HIV-1. To elucidate the biology of HIV-1 infection of intestinal macrophages, we isolated lamina propria macrophages from normal human jejunum by neutral protease digestion, purified the cells by counterflow centrifugal elutriation, and then infected the cells with HIV-1. The lamina propria macrophages were permissive to macrophagetropic isolates of HIV-1 and substantially less permissive to lymphocyte-tropic isolates. Compared with blood monocytes, mucosal macrophages produced 2-3 logs less p24 antigen at peak infection. The reduced level of infection was not due to impaired macrophage viability, reduced CD4 expression, or the isolation procedure. These results confirm that macrophages isolated from the gastrointestinal tract mucosa can support HIV-1 production, albeit at a lower level than blood monocytes. The reduced level of virus production may reflect the unique biology of intestinal lamina propria macrophages.

High prevalence of hantavirus infection in a group of Chinese patients with acute hepatitis of unknown aetiology

In southwestern China, small but substantial numbers of patients with acute hepatitis were found without known hepatropic viral infections (hepatitis A, B, C, D or E, cytomegalovirus, Epstein-Barr virus) and were receiving no hepatotoxic drugs. Prevalence of antibodies, both neutralizing and specific immunoglobulin (Ig)M and IgG, to Hantaan virus were evaluated in a cohort of 136 such patients: 83 were of unknown aetiology, 53 had known viral hepatitis and 59 healthy subjects acted as controls. The results showed that the incidence of neutralizing antibody to Hantaan virus in acute hepatitis patients with non-hepatitis A-E virus infections (13 of 83) was significantly higher than in those with A-E infections (0 of 53, P<0.01). Furthermore, the incidence of specific IgM antibody to Hantaan virus in acute hepatitis patients with non-hepatitis A-E virus infections (6 of 83) was significantly higher than in those with A-E infections (0 of 53, P<0.05) and in healthy subjects (0 of 59, P < 0.05). These findings suggest that Hantaan virus may be an important agent, contributing, at least in southwestern China, to a significant number of the cases of acute hepatitis of unknown aetiology. This hantavirus infection resulted in an acute hepatitis, differing from the typical diseases: haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS).

[Identification of deer's foetus and its mixed drugs and flase drugs]

In this paper, the traditional Chinese Materia Medicas--the foetuses of sika deer, red deer and the one of sheep and OX are compared and identified on characters and dissecting characteristices. The comparion and identification table about charaeters and commodity shape drawings is attached.

[Study on the interaction between CP and DNA]

In this paper, interaction between CP (Cis-ddp or ciplatin) and DNA (deoxyribonucleicacid) was studied using the fluorescence probe as well as the absorption spectra of DAN.

[Character and UV spectral identification of deer's heart]

In this paper, the fresh and dried hearts of Cervus nippon and C. elaphus are identified on character, fluorescence and UV spectra. The alcohol extract of the blood of the deer's hearts has mininum absorption at UV 310 nm.

Mapping undetected mutations within a gene-evidence for two preferential regions in the DMD gene

A maximum-likelihood method is developed to estimate the frequency distribution of undetected mutations (presumably point mutations, small deletions, insertions) along a gene, where the gene extends over a long stretch of DNA. In each family, the point of the mutation is potentially at a different location within the gene. In this sense, there is genetic heterogeneity among families and the method estimates the proportion of families whose mutation is at (or in the vicinity of) a given point inside the gene. Our method is applied to a sample of 75 families with Duchenne muscular dystrophy in which the disease mutation remained undetected. We find two preferential regions for these undetected mutations, with an estimated 85% of families having their mutation in one region and the remaining 15% of families in the other. The new method is expected to be useful in finding small mutations in any of the currently known large genes.

Differential mechanisms in the regulation of endogenous levels of thrombopoietin and interleukin-11 during thrombocytopenia: insight into the regulation of platelet production

The regulation of megakaryocytopoiesis and thrombopoiesis appears to be under the control of an array of hematopoietic growth factors. To determine the relationship of endogenous thrombopoietic cytokine levels and circulating platelet (PLT) counts, we measured the levels of thrombo-poietin (TPO), interleukin-11 (IL-11), and interleukin-6 (IL-6) in patients with significant thrombocytopenia secondary to both marrow hypoplasia and increased PLT destruction. Increased endogenous levels of TPO and IL-11, but not IL-6, were detected in bone marrow transplant patients with thrombocytopenia following myeloablative therapy (BMT/MAT) (TPO: 1,455.5 +/- 87.3 pg/mL, [PLT 39,600 +/- 7,800/microL], P < .001, n = 12; IL-11: 227.9 +/- 35 pg/mL, [PLT 32,900 +/- 57,000/microL], P < .05, n = 19; IL-6: 25.8 +/- 8.4 pg/mL, [PLT 32,800 +/- 5,057/microL], P > .05, n = 4] v normal donors [TPO < 150 pg/mL, n = 8; IL-11 < 50 pg/mL, n = 9; IL-6 < 10 pg/mL, n = 5 [PLT 203,000 +/- 7,500/microL]. There was a significant inverse correlation between endogenous levels of TPO and IL-11, but not IL-6, and PLT counts in the MAT/BMT patients (TPO: r = -0.57, P < .0001, n = 188; IL-11: r = -0.329, P < .0001, n = 249; IL-6: r = -0.1147, P > .05, n = 62). In patients with immune thrombocytopenia purpura (ITP), with decreased PLT survival, but intact bone marrow megakaryocytopoiesis, endogenous IL-11 levels were significantly increased (328.0 +/- 92.6 pg/mL, [PLT: 20,900 +/- 3,000/microL], P < .05, n = 25). However, endogenous TPO levels remained undetectable (< 150 pg/mL, [PLT 30,500 +/- 5,500/microL], n = 15). These results suggest that there may be differential mechanisms regulating endogenous TPO, IL-11, and IL-6 levels during acute thrombocytopenia and suggest that the absolute number of circulating PLTs may not always be the sole regulator of endogenous TPO levels. Other mpl-expressing cells of the megakaryocyte lineage may contribute to the regulation of circulating TPO levels as well. Our results also suggest IL-11 levels may in part, be regulated by a negative feedback loop based on circulating PLT counts, but also may, in part, be regulated by a variety of inflammatory agonists. Both TPO and IL-11, therefore, appear to be active thrombopoietic cytokines regulating, in part, megakaryocytopoiesis during states of acute thrombocytopenia.

Human thrombopoietin levels are high when thrombocytopenia is due to megakaryocyte deficiency and low when due to increased platelet destruction

Thrombopoietin (TPO), the ligand for c-mpl, stimulates proliferation of committed megakaryocytic progenitors and induces maturation of megakaryocytes. To better understand factors regulating TPO levels, we measured blood levels of TPO in patients with impaired platelet production due to aplastic anemia (AA) and with platelet destructive disorders, including idiopathic thrombocytopenic purpura (ITP), posttransfusion purpura (PTP), drug purpura (DP), and X-linked thrombocytopenia (XLTP). The TPO receptor capture enzyme immunoassay (EIA) used had a detection limit of integral of approximately-150 to 200 pg/mL. TPO was undetectable in 88 of 89 normal individuals. Eighteen of 19 patients with AA and a mean platelet count (MPC) of 18,000/microliters (2,000 to 61,000/microliters) had markedly elevated TPO levels (mean, 1,467 pg/mL; range, 597 to 3,834 pg/mL). Eight AA patients who responded to immunosuppressive therapy with their MPC increasing to 140,000/microliters (92,000 to 175,000/microliters) had substantial decreases in TPO (mean, 440 pg/mL; range, 193 to 771 pg/mL). Initial TPO levels did not differ significantly between responders and nonresponders. In contrast, all 21 patients with ITP and an MPC of 16,000/microliters (1,000 to 51,000 /microliters) had undetectable TPO levels, as did 6 patients with acute PTP or DP and 2 patients with XLTP. Megakaryocyte mass, reflected in the rate of platelet production, appears to be the major determinant of TPO levels in thrombocytopenic patients rather than circulating platelet levels per se. Measurement of serum TPO may be useful in differentiating thrombocytopenias due to peripheral destruction from those due to thrombopoietic failure.

Pharmacokinetics and interspecies scaling of recombinant human factor VIII

Recombinant human (rh) factor VIII is a glycoprotein consisting of multiple polypeptides with relative mobilities (M(r)) ranging from 80,000 to 210,000. It is produced in mammalian cells. Single-dose intravenous pharmacokinetic studies were conducted with rh factor VIII (Kogenate rh Antihemophilic Factor, Miles, Inc.) in male mice (21.0-25.8 g) and rats (252.0-254.2 g). Each species received 400 IU/kg, and blood was collected up to 12 hr (mice) or 32.5 hr (rats) post-dose. Immunoreactive factor VIII concentrations in plasma were quantified by a sensitive and specific ELISA. In both species, the disposition profiles were described by the sum of two exponentials. The pharmacokinetics of rh factor VIII in mouse were as follows: clearance, 27.7 ml/hr/kg; initial volume of distribution, 72 ml/kg; steady-state volume of distribution, 148 ml/kg; and terminal half-life, 4.1 hr. In rat, the mean estimates were as follows: clearance, 16.0 ml/hr/kg; initial volume of distribution, 41 ml/kg; steady-state volume of distribution, 125 ml/kg; and terminal half-life, 5.5 hr. These pharmacokinetic parameters for rh factor VIII in animals and human rh factor VIII pharmacokinetic parameters from the literature were evaluated to determine if the parameters can be represented by the allometric relationship, Y = aWb, where Y is the pharmacokinetic parameter, and W is body weight. The following allometric relations were obtained for rh factor VIII: clearance (ml/hr) = 10.4W0.69, half-life (hr) = 7.5 W0.18, initial volume of distribution (ml) = 43.6 W1.04, and steady-state volume of distribution (ml) = 99.1 W0.84. The allometric exponents for each parameter conformed to theory and were within the range of values commonly observed for xenobiotics and therapeutic proteins. These studies suggest that the pharmacokinetics of rh factor VIII in laboratory animals are predictive of the disposition in humans despite the complex nature of its biological interactions and the chemical diversity of the purified material.

Estimate of severe autosomal recessive limb-girdle muscular dystrophy (LGMD2C, LGMD2D) among sporadic muscular dystrophy males: a study of 415 familes

Ninety-five percent of cases of severe muscular dystrophy with early childhood onset result from mutations in the dystrophin region of the human X chromosome (DMD, McKusick 310200), whereas 5% are thought to result from mutations in autosomal genes. We examined a total of 415 families with at least one living patient whose clinical features suggested DMD. Based on formal genetics, haplotype analysis, and dystrophin determinations, we estimate that one in eight (11.8%) sporadic male patients carries autosomal rather than X chromosomal mutations.

[New approaches to evaluation of nonspecific inhalation provocation (dose-response relationship) in the comparative evaluation of bronchial hyperreactivity within the scope of clinical trials]

For the performance of clinical drug trials in the therapy for bronchial hyperresponsiveness, unspecific inhalatory provocation tests are generally employed to judge therapeutic success. In particular, the parameter-specific provocation doses are considered to be the main target values. However, it must be considered that these provocation doses are not equally calculable for every patient in the same way and at any examination time. This leads to the fact that the number of evaluable case studies is often appreciably lower than the number of test participants and that a meaningful therapy group comparison may even not be possible under certain circumstances. An evaluation model is presented here in order to fully exploit the obtained data; in this the percentile changes of the function parameters (estimated by linear regression) at a defined dose of the provocation substance are analyzed. In analogy, a survival time model and, as a supplement, a best case/worst case analysis are performed for further statistical evaluation. With the present procedure, an evaluation with inclusion of all test participants is possible. In contrast to the previously used evaluation procedures, this allows a reliable statistical confirmation of the results of clinical tests in the therapy for bronchial hyperresponsiveness.