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Biomedical subjects

Z Y Zhu

Publications and source records attributed to Z Y Zhu.

12 recordsLinked to original sources
PubMed1992

A variable gap penalty function and feature weights for protein 3-D structure comparisons.

We have developed a variable gap penalty function for use in the comparison program COMPARER which aligns protein sequences on the basis of their 3-D structures. For deletions and insertions, components are a function of structural features of individual amino acid residues (e.g. secondary structure and accessibility). We have also obtained relative weights for different features used in the comparison by examining the equivalent residues in weight matrices and in alignments for pairs of 3-D structures where the equivalencies are relatively unambiguous. We have used the new parameters and the variable gap penalty function in COMPARER to align protein structures in the Brookhaven Data Bank. The variable gap penalty function is useful especially in avoiding gaps in secondary structure elements and the new feature weights give improved alignments. The alignments for both azurins and plastocyanins and N- and C-terminal lobes for aspartic proteinases are discussed.

Amino Acid Sequence↗
PubMed1992

[Localization of the antigen in erythrocytic stages of Plasmodium yoelii by immuno-electron microscopy].

In this study, the antigen recognized by the protective McAb M26-32 in erythrocytic stages of P. yoelii was localized by immuno-electron microscopy with LR Whithe resin embedding and colloidal gold probe cytochemical techniques. The results indicated that the antigen which reacts specifically to McAb M26-32 was mainly localized within the cytoplasm of early and late trophozoites, schizonts and merozoites, being the common antigen of asexual blood stages of the plasmodium. The amount of the antigen was on the increase during the development of trophozoite, while a portion of the antigen might be transported outward by exocytosis of the parasites and then be localized in the cytoplasm of the infected erythrocytes adjacent to the parasites.

Animals↗
PubMed1992

Transcoronary chemical ablation of ventricular tachycardia.

Transcoronary chemical ablation of ventricular tachycardia was recently performed in one patient with refractory ventricular tachycardia in our hospital. The procedure was successful. The arrhythmia was cured and no recurrence occurred in a 24-month period. The clinical application and mechanism of transcoronary chemical ablation were discussed.

Adult↗
PubMed1990

Isolation and characterization of beta-actin gene of carp (Cyprinus carpio).

A beta-actin gene of carp (Cyprinus carpio) was isolated from a genomic EMBL3 library. The nucleotide sequence of the gene indicates six exons spanning 3.6 kb. Southern blot hybridization of restriction endonuclease digests of carp genomic DNA indicate that there are two copies of the beta-actin isotype and several other species of actin genes. The transcriptional start site is 85 bp and 24 bp downstream respectively from consensus CCAAT and TATA promoter elements. The organization of the carp beta-actin gene is identical to that of chicken, human, and rat genes in terms of size, exon/intron locations and junctions and in having a translationally silent first exon. The fish gene is 90% and 99% conserved at the nucleotide and amino acid levels, respectively, with land vertebrate beta-actin genes. Northern blot analysis of beta-actin gene expression indicated that the gene is highly expressed in brain, less so in muscle, and much less so in liver cells. The putative beta-actin proximal promoter of carp, identified by the conservation of known actin regulatory sequences, is transcriptionally active in both mammalian and piscine cells.

Actins↗
PubMed1990

[Studies on the bioavailability of nitrendipine tablet].

The problem of nitrendipine tablets manufactured in China is its low bioavailability. To solve this, a new tablet formulation was developed by using milling method to increase its relative bioavailability. The commercially available conventional tablet A (Nanjing factory) and C (a Hebei factory) and the new tablet formulation D were compared with the reference tablet B (Bayer Company, West Germany) in vitro and in vivo. The determination of nitrendipine in vivo was carried out by GC-MS. The pharmacokinetic parameters of nitrendipine in vivo were estimated by using the nonlinear least square computer program on the basis of the compartment model (zero order dissolution, first order absorption). The bioavailability of A, C and D relative to B was 31.8%, 72.2% and 138.9% respectively. The new tablet formulation D is superior to the imported tablet B in both the extent and rate of absorption.

Biological Availability↗
PubMed1989

Efficacy of inactivated vaccine containing cyto-hemagglutinin against epidemic hemorrhagic fever in rabbits.

Using the Z-10 strain of epidemic hemorrhagic fever virus (EHFV) as seed, and the primary cell of Meriones unguiculatus kidney tissue as incubation cell, a propiolactone inactivated epidemic hemorrhagic fever (EHF) vaccine was prepared, according to a similar procedure required for the production of biological products such as the Japanese B encephalitis vaccine. Besides the EHFV antigen detected by ELISA or reversed passive hemagglutination test (RPHA) as were used for the formalin inactivated vaccine, higher titres (1:128-1:1024) of EHFV hemagglutinin antigen was also detected in this EHFV vaccine. Immunization with twice intramuscular injection of this vaccine produced high titred (1:20-1:160) neutralizing antibody and low titred (1:10-1:20) hemagglutination antibody, in addition to the immunofluorescence (IF) and reversed passive hemagglutination inhibition (RPHI) antibodies. These results indicated an apparent difference in the immunogenicity between the beta-propiolactone and formalin inactivated EHF vaccines. With the approval of the Ministry of Health, human test is now underway in this laboratory.

Animals↗