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X Z Feng

Publications and source records attributed to X Z Feng.

24 records · Page 2Linked to original sources

[Chemical constituents of Armillaria mellea mycelium. VI. Isolation and structure of armillaripin].

A new protoilludane sesquiterpenoid aromatic ester, named armillaripin, C24H30O6, mp 202-204 degrees C, [alpha]D15 + 130 degrees (c 0.055, CHCl3), was isolated from the petroleum ether extract of the artificially cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel. (Tricolometaceae) by silica gel chromatography. On the basis of spectral (UV, IR, 1HNMR 13CNMR and MS) analysis its structure was deduced as I and confirmed by single-crystal X-ray analysis.

Agaricales↗

[Studies on the chemical constituents of Armillaria mellea mycelium. V. Isolation and characterization of armillarilin and armillarinin].

Two new protoilludane sesquiterpenoid aromatic esters, armillarilin C24H30O7, mp 179-180 degrees C, [alpha]D14 + 162 (c 0.97 CHC1(3] and armillarinin C24H29O7 C1, mp 152-155 degrees C, [alpha]D17 + 153.6, (c 0.09, CHC1(3], have been isolated from the artifically cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel (Tricholometaceae). On the basis of spectral (UV, IR, 1HNMR, 13CNMR and MS) analysis their structures were identified as I and II, respectively.

Agaricales↗

Experimental autoimmune arthritis in mice. I. Homologous type II collagen is responsible for self-perpetuating chronic polyarthritis.

Immunisation with heterologous type II collagen (CII) induces arthritis in mice of the DBA/1 strain, which is genetically susceptible to this disease. To develop an experimental model of autoimmunity more adequate for the study of human rheumatoid arthritis (RA), DBA/1 mice were injected with 100 micrograms of native CII that had been purified from mouse xiphoid cartilage. About six weeks later the animals developed a chronic progressive polyarthritis involving the four paws but mainly confined to interphalangeal and metatarsophalangeal joints. The evolution of the disease fluctuated between remissions and exacerbations. The initial lesions assessed by clinical observations were more severe when the disease occurred early than in the case of late onset. Interestingly, the incidence of arthritis was clearly preponderant in males, and, moreover, the few female mice which developed arthritis had mild disease states with lower arthritic scores than the males. Varying levels of autoantibodies against mouse CII were found in the sera of immunised animals, regardless of the development of arthritis. These data indicate that the injection of homologous CII into mice caused a polyarthritis that is clinically closer to the human RA than the disease induced with heterologous CII and therefore will represent a useful tool for the study of the self-perpetuating mechanisms that characterise RA.

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[Induction of flare-ups of chronic progressive polyarthritis in mice after injection of type II homologous collagen].

Immunization by heterologous type II collagen induces in mice a sudden onset of subacute polyarthritis. In order to form a model of auto-immune pathology, we immunized DBA/1 mice with homologous type II collagen extracted from mice xiphoid process; the induced disease corresponds to a progressive chronic polyarthritis with bouts interspersed with remissions, and predominates especially in males. Type II anti-collagen auto-antibodies are found in the serum, with no correlation between the level of mice type II anti-collagen immunoglobulins G and the clinical manifestations of the disease. The histological study demonstrates signs of hyperplastic villous synovitis, with a discrete and infrequent infiltration with mononuclear cells. The model that is obtained is similar to rheumatoid polyarthritis, but also to spondylo-arthropathies.

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