Perturbation of secretory Ig A in saliva and its daily variation by academic stress

Objectives Several studies have reported that the secretory immunoglobulin A (S-IgA) concentration in saliva is an indicator of psychological stress. The aim of this study was to clarify the relationship between S-IgA and the stress from academic examinations. Methods S-IgA levels in 10 medical student volunteers from the second year course between May 4 and July 13, 2000 were examined using the ELISA method. Results There was a tendency for S-IgA in saliva to be higher on the day before academic examinations and during them, and lower on the days between these examinations. Conclusions It may be possible to use this measurement to monitor psychological stress in students and workers. Second year medical student in the year 2000.     

Osteoclast lineage commitment of bone marrow precursors through expression of membrane-bound TRANCE

Osteoclast formation from hemopoietic precursors is induced by TRANCE (also called RANKL, ODF, and OPGL), a membrane-bound ligand expressed by bone marrow stromal cells. Because soluble recombinant TRANCE is a suboptimal osteoclastogenic stimulus, and to eliminate the need for such dependence on stromal cells, membrane-bound TRANCE was expressed in hematopoietic precursors using retroviral gene transfer. Four TRANCE-expressing osteoclast cell lines were established that continuously generate large numbers of multinucleated cells and express tartrate-resistant acid phosphatase and calcitonin receptors. The multinuclear cells are long-lived and either fuse continuously with each other and with mononuclear cells to form enormous syncytia, or separate to form daughter multinuclear cells. When formed on bone, but not on plastic, the majority of multinuclear cells develop actin rings on bone, and resorb bone, suggesting that bone matrix may provide additional signals that facilitate osteoclastic functional maturation. Surprisingly, multinuclear cells originate from fusion of proliferating mononuclear cells that strongly express the mature macrophage markers F4/80 and Fc receptor, which are not expressed by osteoclasts. These results indicate that osteoclasts can be derived from F4/80-positive and Fc receptor-positive cells, and that TRANCE induces osteoclastic differentiation partly by suppressing the macrophage phenotype.     

Phenotypic variation and detection of carrier status in the partial androgen insensitivity syndrome

The partial androgen insensitivity syndrome occurs in 46,XY subjects with phenotypes ranging from perineoscrotal hypospadias with cryptorchidism and micropenis (mild undervirilisation) to clitoromegaly and partial labial fusion (marked undervirilisation). Within an affected family, wide variation in the degree of genital ambiguity between individuals can be seen. Two cousins of a previously reported subject who had severe genital ambiguity and partial androgen insensitivity were investigated. Neither of the cousins had genital abnormalities as marked as the index case, who also had qualitatively abnormal androgen binding and two mutations of the androgen receptor gene. Despite marked phenotypic differences between the index case and his cousins, similar androgen binding and the same androgen receptor mutations were shown in the cousins. Furthermore, one of the androgen receptor gene mutations has been shown in the mother and sister of one of the boys indicating that they are carriers. Thus phenotypic variation in families affected by partial androgen insensitivity is dependent on factors other than abnormalities of the androgen receptor gene alone. Although carrier status in partial androgen insensitivity can be determined, the severity of genital abnormalities in an affected offspring cannot be reliably predicted.     

大鼠实验性急性胰腺炎时血浆和组织脂质过氧化物的变化

本文观察了大鼠实验性急性胰腺炎时血浆和组织脂质过氧化物(LPO)的动态变化。发病后10h动物血浆LPO即见升高,而血浆淀粉酶水平则开始下降。发病10、20h心、肝、肾、肺组织LPO也有不同程度的升高。这证实了氧自由基在急性胰腺炎病理过程中起一定作用。与用血清淀粉酶水平判断急性胰腺炎的发生、发展这一传统方法相比,血浆LPO更能反映急性胰腺炎后期病变的程度及此时全身器官组织受损的情况。