Enhanced resistance to Gram-positive bacterium and increased susceptibility to bacterial endotoxin in mice sensitized with Propionibacterium acnes: involvement of Toll-like receptor.

Mice sensitized with Propionibacterium acnes showed an enhanced resistance against infection with Listeria monocytogenes in contrast to the increased susceptibility to LPS-induced endotoxin shock. The enhanced protection to L. monocytogenes was mediated by activated innate immunity but not by generation of Listeria-specific acquired immunity. After infection with L. monocytogenes, the elimination of bacteria was observed earlier in accordance with a higher level of endogenous cytokine production in P. acnes-sensitized mice than in control mice. Peritoneal cells from P. acnes-sensitized mice produced a larger amount of IL-12p70 and nitric oxide after stimulation with heat-killed L. monocytogenes or peptidoglycan purified from Staphylococcus aureus. RT-PCR analysis showed that the expression of TLR2 but not TLR1, TLR4 nor TLR6 was induced by injection of P. acnes in peritoneal cells. These results indicated that P. acnes-sensitization could induce the activation of innate immunity against L. monocytogenes through increased recognition of bacterial components by TLR2.

[A case of primary pleural leiomyoma].

The chest radiograph = of a 33-year-old man showed a mass shadow in the right hilum. CT scanning film revealed a 3 x 2 cm tumor lying against the right pulmonary artery. Bronchoscopy and pulmonary arteriography showed almost normal findings. VATS tumor extirpation was performed. Macroscopically, the tumor was located in a major fissure. The resected specimen was compatible with leiomyoma. Because no organ of origin of the leiomyoma, other than the pleura, was detected, this case was diagnosed as a primary pleural leiomyoma. Primary pleural leiomyoma is very rare, and this report presents the first such case reported in Japan.

[Cyclosporin improved pure red cell aplasia associated with thymoma and tended to decrease thymoma size: a case report].

The case was a 56-year-old man who underwent extended thymothymectomy in 1993 because of an invasive thymoma classified as Masaoka IIa. The tumor was disseminated through the right thoracic cavity in 1994. Although the chemotherapy was repeated, the disseminated thymoma tended to increase in size. The patient was suffering from severe anemia, and pure red cell aplasia was diagnosed in September 2002. The administration of cyclosporin was initiated, and not only brought about improvement of pure red cell aplasia but also tended to shrink the thymoma. Cyclosporin may be an effective drug for the reduction of thymoma as well as for pure red cell aplasia.

[A case of rebamipide-induced pneumonitis].

A 75-year-old man who complained of progressive dyspnea was admitted to our hospital. He had been treated with rebamipide at an outpatient clinic for the preceding seven months. Atrial blood gas values obtained on admission indicated hypoxemia. Chest radiographs and CT films revealed diffuse interstitial infiltration and minimal pleural effusion. Bronchoalveolar lavage fluid showed an increase in the total cell number, the percentages of eosinophils and lymphocytes, and a decrease in the CD4/CD8 ratio. Transbronchial lung biopsy specimens had thickened alveolar septa with lymphocyte infiltration within the air spaces. After the discontinuation of rebamipide, oral prednisolone was administered, and the patient's symptoms and pulmonary shadows quickly improved. A lymphocyte stimulating test for rebamipide was positive. A challenge test for rebamipide was not performed because informed consent could not be obtained. On the basis of these findings, our diagnosis was rebamipide-induced pneumonitis.