Prostaglandin-related immune suppression in cattle.

Prostaglandins (PGs) are lipid mediators derived from arachidonic acid by several enzymes including cyclooxygenase (COX)-1 and COX-2. We have previously shown that PGE2 regulates immune responses, such as Th1 cytokine production and T-cell proliferation, in cattle. However, it is still unclear whether other PGs are involved in the regulation of immune responses in cattle. Here, immunosuppressive profiles of PGs (PGA1, PGB2, PGD2, PGE2, PGF1α and PGF2α) were firstly examined using bovine peripheral blood mononuclear cells (PBMCs). In addition to PGE2, PGA1 significantly inhibited Th1 cytokine production from PBMCs in cattle. Further analyses focusing on PGA1 revealed that treatment with PGA1 in the presence of concanavalin A (con A) downregulated CD69, an activation marker, and IFN-γ expression in both CD4+ and CD8+ T cells. Sorted CD3+ T cells stimulated with con A were cultivated with PGA1, and IFN-γ and TNF-α concentrations decreased upon PGA1 treatment. Taken together, these results suggest that the treatment with PGA1in vitro inhibits T-cell activation, especially Th1 cytokine production, in cattle.

Molecular cloning and characterization of Th1 and Th2 cytokines of African buffalo (Syncerus caffer).

The African buffalo (Syncerus caffer) has been implicated as the reservoir of several bovine infectious agents. However, there is insufficient information on the protective immune responses in the African buffalo, particularly in infected animals. In this study, we analysed Th1 cytokines IL-2 and IFN-γ, and Th2 cytokines IL-4 and IL-10. The cloned cDNA of IL-2, IL-4, IL-10 and IFN-γ contained an open reading frame of 468, 501, 408 and 540 nucleotides, encoding polypeptides of 155, 166, 135 and 179 amino acids, respectively. Nucleotide sequence homology of IL-2, IFN-γ and IL-4 was more than 98% between the African buffalo and cattle, which resulted in identical polypeptides. Meanwhile, IL-10 gene of African buffalo and cattle had 95% homology in nucleotide sequence, corresponding to thirteen amino acid residues substitution. Cysteine residues and potential glycosylation sites were conserved within the family Bovinae. Phylogenetic analyses including cytokines of the African buffalo placed them within a cluster comprised mainly of species belonging to the order Artiodactyla, including cattle, water buffalo, sheep, goat, pig and artiodactyl wildlife. A deeper understanding of the structure of these cytokines will shed light on their protective role in the disease-resistant African buffalo in comparison with other closely related species.

[Endobronchial hamartoma suspected lung cancer due to false positive of fluorodeoxyglucose-positron emission tomography; report of a case].

A 63-year-old male was referred to our hospital with an abnormal shadow on chest radiography and computed tomography. A transbronchial lung biopsy did not reveal any malignant lesion. A fluorodeoxyglucose-positron emission tomography (FDG-PET) was done for further examination and it revealed positive. Right upper lobectomy was perfomed for both diagnosis and treatment. The pathological diagnosis was endobronchial hamartoma The FDG-PET was false positive because of its atelectasis with obstructive pneumonia

The effects of facial fanning on thermal comfort sensation during hyperthermia.

We studied how facial fanning during hyperthermia improves the thermal comfort sensation. Experiments were carried out on ten male subjects. They were immersed in hot water at 40 degrees C for 45 min. At 20 min and 35 min, fanning (1 m x s(-1)) was applied to their faces for 5 min. Core temperature (Tc) measured as esophageal temperature (Tes) and tympanic temperature (Tty) continued to rise during the immersion, but temporarily decreased during fanning with a delay of 2 or 3 min. Skin temperatures (Ts) on the forehead and cheek continued to increase slightly during immersion, but decreased immediately after the start of fanning. During immersion before face fanning, the time trend of thermal sensation towards the warm level was similar to that of skin temperature on the face, whereas the time trend of thermal comfort ratings towards the uncomfortable level was similar to that of Tc. The scores of both thermal sensation and thermal comfort were reduced significantly immediately after the start of fanning, and their time courses were different to those of Ts and Tty. These results support previous reports that thermal sensation depends on skin temperature, and that thermal comfort depends on both the skin and core temperatures. Moreover, they indicate that both thermal sensation and comfort ratings are affected by the dynamic responses of the cutaneous thermoreceptors when fanning is applied to the face during hyperthermia.

Strain on the gastrocnemii and hamstrings affecting standing balance on an inclined plane in spastic cerebral palsy. A study using a geometric model.

The purpose of this study was to use an non-invasive method to determine whether strain on the gastrocnemii and hamstrings influences postural balance in spastic cerebral palsy (CP). Changes in alignment during standing posture with subjects positioned on a platform that was gradually inclined were measured in 10 normal children and 11 children with CP. The changes in postural alignment were plotted and geometric models used to determine the lines where the gastrocnemii and hamstrings were maximally stretched. In this way the relationship between postural alignment and the amount of strain on the gastrocnemii and hamstrings was investigated. On the inclined platform, which caused ankle joints to become dorsiflexed as the inclination angle increased, the gastrocnemii began to be strained and the hip joints began to be flexed (trunk bent forward) at the same time. In the children with CP, the gastrocnemii were more strained by smaller degrees of inclination. Furthermore, there was one child with CP whose hamstrings were also strained on the inclined platform. We confirmed that postural balance was affected by strain on the gastrocnemii and hamstrings.

Effects of different absorption enhancers on the permeation of ebiratide, an ACTH analogue, across intestinal membranes.

The permeation of ebiratide (H-Met(O2)-Glu-His-Phe-D-Lys-Phe-NH(CH2)8NH2), a novel ACTH analogue, across the intestinal mucosae has been examined by use of isolated intestinal membranes from rats in a modified Ussing chamber. Regional differences were observed in the permeation of ebiratide across intestinal membranes; the order of membrane permeability was jejunum > ileum > duodenum > colon. Overall, the permeation of ebiratide was relatively poor. The effects of various absorption enhancers were examined to increase the intestinal permeability to ebiratide. Sodium glycocholate and sodium caprate had no significant enhancing effect on the permeability of the jejunal membrane, but significantly enhanced the permeation of ebiratide through the colonic membrane. On the other hand, N-dodecyl-beta-D-maltopyramoside (LM) significantly enhanced the permeation of ebiratide through both jejunal and colonic membranes. In general, the absorption-enhancing effects of these agents were more predominant in the colon than in the jejunum. Membrane damage by the absorption enhancers was evaluated by measuring the amount of protein released from the intestinal membrane. It was found that all the absorption enhancers slightly increased the amount of protein released, but that the amounts of protein released in the presence of these enhancers were much less than in the presence of ethylenediaminetetraacetic acid (EDTA), used as a positive control. These findings suggest that the absorption enhancers, especially LM might be useful adjuvants for improving the intestinal absorption of peptide and protein drugs, including ebiratide.

Susceptibility of ebiratide to proteolysis in rat intestinal fluid and homogenates and its protection by various protease inhibitors.

In order to estimate the intestinal stability of ebiratide [H-Met(O2)-Glu-His-Phe-D-Lys-Phe-NH(CH2)8-NH2], a novel adrenocorticotropic hormone (ACTH) analogue, after oral administration, the hydrolytic properties of ebiratide were determined in the rat small intestinal fluid and mucosal homogenates. Ebiratide was extremely stable in the rat small intestinal fluid, while it was degraded in various intestinal mucosal homogenates. Regional differences were observed in its proteolytic properties; e.g., the hydrolytic rates of ebiratide in jejunal and ileal mucosal homogenates were 2-3 times faster than that in duodenal and colonic homogenates. Degradation of ebiratide was markedly inhibited by aminoprotease inhibitors such as sodium glycocholate, puromycin, bestatin and bacitracin. These results suggest that co-administration of certain protease inhibitors are useful to improve the stability of ebiratide in the intestine.

Effects of electric current on chondrogenesis in vitro.

The effect of direct electric current (5 muamp) on mesenchymal cell differentiation into cartilage was investigated in explants of fetal rat muscle and bone matrix gelatin. In this system, chondrogenesis in vitro corresponds in developmental potential to osteogenesis in vivo. Application of electric current inhibited differentiation of muscle derived mesenchymal cells, but enhanced proliferation of differentiated chondrocytes and formation of cartilage at the cathode region, and had no effect on mature hypertrophic chondrocytes. Application of electric current may be contraindicated in fracture at the very early stage of fracture treatment and effective at the cathode region only for preexisting and proliferating cells. Electric current also may not be effective for mature cells having no potential for proliferation.