The interaction between native serum albumin and hepatitis B virus

Summary Purified hepatitis B virus particles were obtained from HBeAg positive serum by sucrose gradient ultracentrifugation and sephadex G-200 gel filtration. These virions formed a precipitation line in counterimmune electrophoresis with anti-albumin antibody, but the reaction could be inhibited by anti-HBs. After two months at 4°C, another precipitating line was formed under the same condition which could not be inhibited by anti-HBs and was, thus, due to free albumin. When that sample was incubated at 37°C overnight, the line of free albumine disappeared. The virion bound albumin was monomeric in non-denaturing gel electrophoresis. These results suggest that a reversible binding between virion and albumin may occur in vivo and does not require chemical modification or cross-linking.     

Competitive, enzyme-linked immunosorbent assay for toxic shock syndrome toxin 1.

We developed a competitive, enzyme-linked immunosorbent assay for the quantitation of toxic shock syndrome toxin 1 (TSST-1). Polyvalent immunoglobulin G from immunized rabbits was used as the capture antibody, and alkaline phosphatase conjugated to purified toxin served as the indicator enzyme. A standard curve was generated with each experiment, from which the concentration of toxin in culture supernatants was extrapolated. The assay was useful for determining toxin concentrations of 0.03 to 0.5 micrograms/ml, which is a substantial, practical improvement over immunodiffusion methods. Staphylococcal enterotoxins A through E were not significantly cross-reactive in the assay, and staphylococcal protein A did not interfere with quantitation of TSST-1. By testing a variety of staphylococcal strains, we found 100% concordance between toxin determinations made with our assay and those made by the investigators from whom the strains were obtained. The competitive, enzyme-linked immunosorbent assay is a highly reproducible, inexpensive means of determining TSST-1 concentrations and may have broad applicability in the field of toxic shock research.     

Release of prolactin and luteinizing hormone by histamine agonists in ovariectomized,steroid-treated rats under ether anesthesia

Responses to histamine agonists administered intraventricularly under ether anesthesia were analyzed to evaluate receptor mediation in histamine stimulation of prolactin and LH release in ovariectomized, estradiol-progesterone-treated rats (OVX-E2P-treated rats). Prolactin release was markedly increased by the H2-histamine agonists, 4-methyl histamine and Dimaprit. These effects were antagonized by metiamide, an H2-blocking agent. The H1-histamine agonist, 2-(2-pyridyl)ethylamine (PEA) in high doses released prolactin and its effect was partially prevented by metiamide. Mepyramine, and H1-antagonist, did not exert any effect on the release of prolactin enhanced by the histamine agonists. LH release was significantly increased after 4-methyl histamine administration. Its effect was weak and was blocked by metiamide. Neither Dimaprit nor PEA exhibited action on plasma LH levels. The results obtained with histamine agonists suggest that histamine evokes prolactin release in OVX,E2P-treated rats through H2-receptors. At present, conclusions on H2-receptor mediation in LH release induced by histamine cannot be drawn from these results. The above-mentioned data, however, conclusively discard a significant participation of H1-receptors.     

Immune response to Trichomonas vaginalis. IV. Immunochemical and immunobiological analyses of T. vaginalis antigen

The immune response of patients with trichomoniasis vaginitis to Trichomonas vaginalis was examined by using passive hemagglutination assay and skin reactions. Trichomonas-specific immune responses could hardly be detected in the patients by these assay methods. In order to develop a simple and reliable assay for demonstration of T. vaginalis-specific immune responses in the patients, proliferation responses of peripheral mononuclear cells from the patients were examined. Lymphocytes obtained from the patients were shown to incorporate 3H-methyl-thymidine when stimulated with T. vaginalis antigen in vitro. Furthermore, immunochemical analysis of T. vaginalis antigen has been done by Sephadex chromatography and sodium dodecyl sulfate gel electrophoresis. The data revealed that the murine and human IgM antibodies specific to T. vaginalis recognize various antigens with a wide range of molecular weights (between 13,000 and 100,000 daltons), while human and murine IgG antibodies recognize molecules with a much narrower range of molecular weights (50,000-100,000 daltons).     

SSAHA: a fast search method for large DNA databases

We describe an algorithm, SSAHA (Sequence Search and Alignment by Hashing Algorithm), for performing fast searches on databases containing multiple gigabases of DNA. Sequences in the database are preprocessed by breaking them into consecutive k-tuples of k contiguous bases and then using a hash table to store the position of each occurrence of each k-tuple. Searching for a query sequence in the database is done by obtaining from the hash table the "hits" for each k-tuple in the query sequence and then performing a sort on the results. We discuss the effect of the tuple length k on the search speed, memory usage, and sensitivity of the algorithm and present the results of computational experiments which show that SSAHA can be three to four orders of magnitude faster than BLAST or FASTA, while requiring less memory than suffix tree methods. The SSAHA algorithm is used for high-throughput single nucleotide polymorphism (SNP) detection and very large scale sequence assembly. Also, it provides Web-based sequence search facilities for Ensembl projects.     

Biochemical and biophysical analysis of heptad repeat regions from the fusion protein of Menangle virus,a newly emergent paramyxovirus

E. coli in vitro expression system. The GST-removed purified 2-Helix protein could form a stable trimer in vitro judging by gel-filtration and chemical cross-linking. CD spectra showed that the 2-Helix protein had a high percentage of α-helix and was very thermo-stable. Crystals of the 2-Helix protein preparations have been obtained in many conditions with hanging-drop diffusion method. These results indicated that Menangle virus has the common features of the fusion protein for other paramyxoviruses and should adopt a similar fusion mechanism to other members. As the HR regions of Menangle virus F protein could form stable six-helix bundle coiled coil structure, they should be used as drug target for the design of fusion inhibitors, as successfully used for other parmyxoviruses. This is especially relevant to such a newly emergent virus with zoonotic potentials. Received January 23, 2003; accepted February 28, 2003 Published online April 28, 2003     

甲襞、球结膜微循环的应急观测方法

甲襞、球结膜微循环的应急观测方法是在甲襞、球结膜微循环加权积分综合定量评价方法的基础上，保留权值为４、３的指标，同时观察血管清晰度和红细胞聚集二项指标而形成。同时提供其应急观测积分表、异常分度积分值、诊断标准，并与常规方法进行比较，证明其可以反映绝大部分流态类指标和大部分形态类指标及重要的袢周改变，没有丢失微循环重度异常的信息，保证了重度异常诊断的正确。但在大致正常、轻度异常和中度异常的诊断中应急方法部有判重的倾向，说明应急方法漏掉了一些信息，不能全面地了解微循环的改变，造成了判重的倾向。因此应急方法不能代替常规方法，只能在特定条件下应用。     

Apoptotic rate in peripheral T-cell lymphomas. A study using a tissue microarray with validation on full tissue sections

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of non-Hodgkin lymphomas with a wide spectrum of clinicopathologic features, and apoptosis mechanisms may have a role in lymphomagenesis. We assessed apoptotic rate (AR) in 112 PTCLs using a tissue microarray developed in our laboratory and a modified terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. The mean AR was 1.47% +/- 1.38% for the entire group of PTCLs (range, 0.06%-5.15%), and AR varied significantly among different tumor types. In mycosis fungoides, the mean AR was 0.74%; angioimmunoblastic T-cell lymphoma, 1.02%; PTCL, not otherwise specified, 1.38%; cutaneous anaplastic large cell lymphoma (ALCL), 1.41%; anaplastic lymphoma kinase protein (ALK)-negative ALCL, 1.43%; extranodal natural killer/T-cell lymphoma of nasal type, 2.04%; ALK-positive ALCL, 2.95%; and enteropathy-type T-cell lymphoma, 3.06%. Mean AR was higher in PTCL with large cell vs small/medium cell morphologic features (1.66% +/- 1.1% vs 0.99% +/- 1.0%). In a subset of 33 PTCLs, the tissue microarray results comparedfavorably with those obtained in full tissue sections. We conclude that the highest ARs in PTCLs are found in enteropathy-type T-cell lymphoma and ALK-positive ALCL, and that AR can be assessed reliably by using a tissue microarray.