Systematic expression profiling of innate immune genes defines a complex pattern of immunosenescence in peripheral and intestinal leukocytes.

Immunosenescence is characterized by a quantitative decline of adequate immune responses, which renders the elderly individual particularly susceptible to bacterial, viral and fungal pathogens. Whereas changes of the aging adaptive immune system (for example, reduced immunoglobulin secretion) have been extensively characterized, alterations of the innate immune system are still poorly understood. The aim of the present study was to systematically examine mRNA expression levels of innate immune genes and proinflammatory cytokines in peripheral and intestinal leukocytes of subjects of different ages. In both, whole blood samples and in colonic biopsies most of the Toll-like receptors (TLRs) and nucleotide-binding and oligomerization domain-like receptors (NLRs) transcript levels were significantly downregulated in elderly subjects (90-99 years). Older individuals, when compared to the younger, exhibited an increased expression and/or secretion of proinflammatory cytokines by peripheral and intestinal leukocytes as well as an increased level of nuclear factor-kappaB activation in colonic biopsies. The observed downregulation of TLRs and NLRs during the aging process may contribute to the lack of effective recognition of invading pathogens or the commensal flora. This effect results in aberrant secondary immune cell activation and could significantly contribute to morbidity and mortality at advanced age.

Long distance image transfer: first results of its use in histopathological diagnosis.

Histopathological images were transferred by use of normal telephone lines between three pathology institutes located in three different cities in the FRG. Images were digitized using a colour TV camera and stored in a special computerized image transmission system. The stored image was transferred and visualized on a (receiver) colour TV screen after dialing the telephone number connected to the receiver image transmission system. An additional telephone dialogue was activated by use of a normal acoustic telephone, and the diagnostic difficulties of the underlying image were discussed. Diagnostic assistance was possible in all transferred cases as well as histopathological diagnosis. Resolution of the images was set at 512 x 512 pixel x 8 bit. Image transfer time was 3.2 min on average. The differences between the original and transferred image were measured by "retransfer" of the original image and by subtracting the two images from each other. No major transfer errors could be measured.