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Biomedical subjects

X Zeng

Publications and source records attributed to X Zeng.

210 records · Page 12Linked to original sources

[Prophylactic effect of refined amorphophallus konjac on MNNG-induced lung cancers in mice].

Three hundred and seventy LACA mice of seven weeks old were used in 2 batches for studying the prophylactic effect of Konjaku powder on MNNG-induced lung cancers. These mice (within each batch) were randomly allocated to four groups, namely positive control (MNNG), refined Amorphophallus Konjac (R.A.K.), complex (MNNG + R.A.K.), and blank control (C). In MNNG group, MNNG (250 micrograms) was injected intravenously once five days for seven times in each mouse, the total dosage of MNNG was 1.75 mg. In R.A.K. group, according to w/w, 8% R.A.K. was well mixed into 92% common diet for long-term term breeding. In complex group, MNNG was given as that in MNNG group and the mice were reared as those in R.A.K. group. The mice in MNNG group and in C group were all reared by common diet. The results of experiments showed different degrees of preventive effect of R.A.K. on MNNG-induced lung cancers in LACA mice. R.A.K. not only exerted effect on the number of induced cancer, causing a drop of the cancerous rate from 79.75% to 20.00% and the mean number of cancer in each animal, but also prolonged the survival time of animals. At the same time, the constituent ratio of the kinds of tumor denoted a decrease in malignancy (adenoma with malignant change), an absence of adenocarcinoma and relative increase in benign adenoma. The results of experiments also exhibited good duplication as well as absence of adverse reactions to Konjaku powder.

Animals↗

[Small-airway lesions induced by inhalation of asbestos dust in dogs--pathological and aetiological studies].

This paper presents the pathological changes of the small airways of dogs inhaling asbestos dust in the workshop of Xin Kong Asbestos Mine for 1 to 3 years. Dogs of the experimental group showed that variable degrees of dust deposition and fibrous tissue reaction were found in all the three types of the small airways-respiratory bronchioles, alveolar ducts and membranous bronchioles of both lungs. The lesions in the lung increased with the duration of exposure. These changes in the canine small airways resulting from asbestos dust were very much similar to those of the humans. In addition, deposited dust collected from the workshop of the asbestos mine, and 50 dust particles selected randomly in foci were identified in situ by energy dispersive X-ray analysis. Findings demonstrated that the majority of the dust particles in the foci was principally mixed silicate dust. Among them asbestos dust predominated absolutely, and there were more amphiboles than chrysotiles. Therefore, it is concluded that the small airway lesions induced in the dogs are mainly due to mixed asbestos dust, and that there appears to exist a dose-response relationship.

Animals↗

[Chemical constituents of Osbeckia chinensis L].

Five constituents, 2-furoic acid, succinic acid, ursolic acid, quercetin and daucosterol were isolated and identified from Osbeckia chinensis. All of them are reported to have been found from this plant for the first time.

Anti-Infective Agents↗

[Research on the relationship between central acetylcholine and acupuncture analgesia].

The article systematically reported our physiological and biochemical work on the relationship between central acetylcholine and acupuncture analgesia. The results indicate: 1. Acupuncture on acupoints could produce analgesia. 2. Ach contents in cerebrospinal fluids and brain increased under acupuncture analgesia. 3. AChE activities iu brain elevated under acupuncture analgesia. 4. ChE inhibitor reinforced the effects of acupuncture and inhibitor of ACh synthesis could inhibit the effects of acupuncture, which could be reversed by administration of ACh and chlorocholine. M-AChR antagonists could also inhibit the effects of acupuncture. 5. The turnover rate of ACh in diencephalon, caudate nucleus and spinal dorsal horn accelerated when acupuncture analgesia. The discussion was given on the variation of metabolic dynamics in combination with related literature.

Acetylcholine↗

Preliminary observations on the phenotypes of lymphoid cells in mycosis fungoides using anti-human-thymocyte monoclonal antibodies.

The phenotypes of lymphoid cells from twelve patients with mycosis fungoides (including 5 patients in the tumor stage and 7 in the pretumor stage) were determined immunohistochemically using anti-thymocyte monoclonal antibodies (HIT1, HIT2, and Leu 6). The results showed significant differences between the numbers of HIT1 and HIT2 positive cells in tumor and pretumor stage lesions, indicating that these two monoclonal antibodies may be of help in the staging of mycosis fungoides and in making a prognosis. Also, we found that some Leu 6 (+) cells in tumor stage lesions were round or oval in shape without dendritic processes, suggesting that they may be immature lymphocytes.

ADP-ribosyl Cyclase↗

Membrane chromatography: preparation and applications to protein separation.

As a result of the convective flow of solutes through porous membranes, membrane chromatography has a higher capture efficiency and a higher productivity than column chromatography and shows most promising industrial applications for the recovery, isolation, and purification of proteins and enzymes. This paper presents a comprehensive review of the methods for preparation of adsorptive membranes (such as surface modification, in situ copolymerization, direct formation from hydrophilic materials, and functionalized particulate-entrapped membranes) and deals particularly with novel macroporous chitin and chitosan membranes for protein separations developed by the authors.

Carbohydrate Sequence↗

B-cell epitopes recognized by Chinese water buffaloes (Bos buffelus) on the 22 kDa tegumental membrane-associated antigen (Sj-22) of the Asiatic bloodfluke, Schistosoma japonicum.

The 22.6 kDa tegumental membrane-associated antigen of schistosomes is of recognized importance in immunity to schistosomiasis. In China, bovines are known to play an important role in the transmission of Schistosoma japonicum. Ten buffaloes (Bos buffelus) were vaccinated with a recombinant form (reSj-22) of the S. japonicum 22.6 kDa tegumental antigen (Sj-22) and the sera were used to identify and map possible linear B-cell epitopes on this molecule using a series of 18 overlapping synthetic peptides (P1-P18). Sera from all of the ten vaccinated buffaloes reacted strongly with Sj-22 in western blots and in ELISA, while sera from a further ten adjuvant (Quil A) control buffaloes did not. Four peptides (P3, P8, P9 and P10) were predominantly recognized by at least 90% of the buffalo sera. This pattern of recognition is similar to that obtained in a previous study we undertook in mice immunized with the same antigen whereby peptides 3, 8, 9 and 10 were recognized by over 80% of CBA strain mice. The peptide most frequently recognized by mice (peptide 6), and mapping to an EF-hand calcium binding domain, was recognized by six of the ten vaccinated buffaloes. The major difference between buffaloes and mice occurred with peptide 1 which was recognized very frequently by all three strains of mice tested but was only weakly recognized by three of the ten buffaloes. This study provides a valuable reference for further study on the immunity stimulated by the 22.6 kDa tegumental antigen in the murine model and a natural bovine host of Schistosomiasis japonica.

Amino Acid Sequence↗