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Biomedical subjects

J Zuo

Publications and source records attributed to J Zuo.

103 records · Page 6Linked to original sources
PubMed1985

New evidence for the inhibition by harringtonine in the formation of the first peptide bond in protein synthesis.

New evidence for the inhibition by harringtonine in the formation of the first peptide bond in protein synthesis was obtained by means of experiments in the cell-free system. The antitumour drug strongly blocked dipeptide synthesis in the system without elongation factor G and GTP. Furthermore, it inhibited N-Acetyl-phenylalanyl-puromycin formation from N-Acetyl-phenylalanyl-tRNA, puromycin, and ribosomes.

Alkaloids↗
PubMed1982

Studies on the mechanism of indirubin action in the treatment of chronic granulocytic leukemia. V. Binding between indirubin and DNA and identification of the type of binding.

The binding between indirubin and calf thymus DNA in vitro has been verified by means of the isotope labelling method, spectrophotometric method and thermal denaturation measurements. The lambda max 207 nm of indirubin shifted toward longer wave length with decrease of absorbance after the incubation of indirubin with DNA. The escalation of Tm value of DNA induced by indirubin was about 2.4 degrees C and it was reproducible. The binding force between them was rather weak, as indirubin molecules were easily released during the precipitation with alcohol or the gel filtration. The binding was not affected by sodium chloride even at high concentration but greatly decreased (to 20-30% of the control) in the presence of 8 M urea. These results showed that the binding between indirubin and DNA might be of hydrogen bond rather than ionic. The amount of bound 3H-indirubin was directly proportional to the concentration of indirubin. However, it increased abruptly when the concentration of indirubin reached 1.5 x 10(-4) M. This suggested another binding force in the latter instance. By using spectrophotometric analysis and Scatchard plot it was found that calf thymus DNA bound 46 indirubin molecules/1000 nucleotides. The association constant (K) was 5.7 x 10(6).

Animals↗
PubMedDate not supplied

A micro creeping robot for colonoscopy based on the earthworm.

Minimally Invasive Surgery (MIS) has become one of the most important research areas in the field of medical engineering. Robotic colonoscopy is a typical medical procedure that complies with the requirements of MIS. In this paper, a new novel miniature robot for intestinal inspection based on the earthworm is described; its diameter and length are 7.5 mm and 120 mm respectively. The micro robot is driven by a DC motor which has good performance and sufficient power. In this paper the structure and locomotion mechanism of this robot are introduced; the mechanical model is built; and simulation is carried out. The control system and software design are also discussed in detail. Some actuating characteristic experiments have been performed, where the micro robot creeps in declining rubber tubes. The experimental results are in accord with simulation results, and show that this kind of robot can move reliably in horizontal and certain declining tubes. This research has laid a foundation for the application of the miniature robot endoscope.

Animals↗
PubMedDate not supplied

Inspection for gastric occult blood at regular intervals is the optimum program for the screening of esophageal-gastric cancer.

Gastric occult blood screening has been performed for 242296 persons from 1986 to 1993. 30227 persons had positive reactions to the occult blood reagent. Among them, 17915 persons were asked to accept gastroscopy exam, and 638 esophageal-gastric cancers were found. The cancer detection rates were 3.56%. 4774 persons were asked to accept screening twice and 203 persons were asked to accept screening three times. After follow-up, the cancer detection rates were 2.11% for occult blood positive group if the screening was conducted once a year. The missing case was 0.77% for negative group and it was 0.05% in the same group if the screening was performed twice. Lastly, the missing case would be decreased to 0% when the patients undergone the exam, for three times in continuity. Two thirds of patients still belonged to the early-middle stage of cancer. The 5-year survival rates were 95.2%. The missing case of cancer would be reduced to 0% if the screening was conducted for three years in continuity. The death rates were deducted as well. It is certified that this method is the most effective and reliable way for reducing the death rate of cancer and screening of the upper digestive tract cancer.

Adolescent↗