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Biomedical subjects

B F Yu

Publications and source records attributed to B F Yu.

5 recordsLinked to original sources
PubMed1994

A rodent model for Wilms tumors: embryonal kidney neoplasms induced by N-nitroso-N'-methylurea.

Embryonal kidney cell tumors develop in rats given the alkylating agent N-nitroso-N'-methylurea as neonates. These tumors resemble the childhood Wilms tumors in their histopathology. Deletions and mutations in the Wilms tumor suppressor gene, WT1, are present in up to 6% of childhood nephroblastomas. To investigate the role of WT1 in rat kidney tumorigenesis, we studied the genetic alterations in WT1 and its target genes. Point mutations were found in WT1 cDNA in 7 of 18 kidney tumors. Mesenchymal tumors contained G-->A transition mutations in codons 128, 364, and 372, typical of the methylating action of N-nitroso-N'-methylurea on DNA. Each of the four nephroblastomas contained the same T-->A mutation at codon 111 of WT1, reflective of transversion mutagenesis by N-nitroso-N'-methylurea in vivo. Like Wilms tumors, mRNA levels of WT1, IGF2, Pax-2, and MK genes were higher than newborn kidney in the majority of the tumors. The histopathology of the rat kidney tumors and the genetic alterations are reminiscent of those observed in Wilms tumors, establishing this as a relevant model system for the human disease.

Animals↗
PubMed1990

[Preliminary clinical application of new bone marrow imaging agent 99mTc-polyphase liposome in malignant lymphoma].

Bone marrow (BM) imaging with 99mTc-polyphase liposome in 30 malignant lymphoma patients demonstrated that central BM hypoplasia accounted for 90% (28/30) and peripheral BM hypoplasia 20% (6/30) with peripheral BM expansion of 80% (23/30). Focal BM lesion was shown in 7 patients which conformed with the results of bone imaging and X-ray film. The uptake index of BM in patients treated with chemotherapy was low as compared to that in patients treated with radiotherapy (P less than 0.05). Although BM suppression by chemotherapy was more severe than by radiotherapy, BM function essentially recovered 1 month after cessation of chemotherapy, on the other hand, while central BM suppression by radiotherapy was mild, it lasted for longer periods of time. Peripheral BM suppression by radiotherapy was both shorter in duration and milder in severity in comparison with central BM suppression. BM imaging is valuable for the understanding of BM function, ascertainment of the appropriate interval between treatments and early detection of local BM involvement.

Adult↗
PubMed1989

[Clinical and experimental research on lutongning in treating vascular headache].

Observing the therapeutic effect of 350 cases of vascular headache patients treated with oral Lutongning decoction and goat horn compound separately, and comparing the effects of these two groups' patients, they showed that the former was much better than the latter. The author found that cure rates of these two groups were 75.3% and 56% respectively (P less than 0.01). The medicinal action of the former was also faster than that of the latter, and the time to recover was shorter. So, Lutongning was an effective prescription in the treatment of vascular headache. In order to research the effective mechanism of Lutongning on vascular headache, the animal experiment was carried out. The hot-plate method and acetic acid body-turning method were used for the experiment in rats. After perfusing Lutongning into the rat's stomach, the author found that the reaction times by hot-plate method and the turning times by acetic acid body-turning method were less than those of the control animals. The result showed that the analgetic effect of this decoction was more obvious.

Adolescent↗
PubMed1988

[A new lymph node imaging agent--99mTc-polyphase liposome oleatis (99mTc-plo)].

A new lymph node radio-imaging agent, technetium-99m polyphase liposome oleatis (99mTc-plo), has recently been developed. Polyphase liposome oleatis was labelled with radionuclide by stannous chloride method. The labelled rate was 90% or more as technically identified by thin layer chromatography, external gamma-camera imaging and radioautography. In animal experiment, 0.2-0.3 ml (0.2 mci) of the 99mTc-plo was injected subcutaneously into the toes web of rats. After half an hour, the regional lymph nodes of popliteal fossa were visualized very clearly. The imaging figures may keep their distinct shadow up to 24 hours. The tested rabbits were sacrificed 10 hours after 99mTc-plo injection for detecting various kinds of tissue and organ with a scintillation counter. The regional lymph nodes revealed the highest uptake rate of the new agent, 12,116; 1,303; 1,615 times higher than that of the adjacent muscles, liver and spleen, respectively. In clinical experiment, 0.2-0.3 ml (0.5-0.8 mci) of the 99mTc-plo was injected subcutaneously into the toes web of patients. Half an hour later, the lymph nodes of inguinal, external iliac and common iliac regions appeared in sequence. If the new agent is injected perianally, the internal iliac lymph nodes will be seen. No side effect was observed in both types of experiment. This new agent has been tried in rats, rabbits and dogs with similar positive results. The new lymph node imaging technique is simple, safe, reliable and reproducible. This agent, being directed toward the lymph nodes and possessing affinity to cancer cells, is expected to be supplementary method to CT and B-ultrasonography for detecting lymphoid malignancy and lymph node metastasis.

Animals↗