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Prion infections of the central nervous system (CNS) are characterized by initial reactive gliosis followed by overt neuronal death. Gliosis is likely to be caused initially by the deposition of misfolded, proteinase K-resistant, isoforms (termed PrPSc) of the normal cellular prion protein (PrPc) in the brain. Proinflammatory cytokines and chemokines released by PrPSc-activated glia and stressed neurons may also contribute directly or indirectly to the disease development by enhancing gliosis and inducing neurotoxicity. Recent studies have illustrated that early neuroinflammation activates nuclear factor of activated T cells (NFAT) in the calcineurin signaling cascade, resulting in nuclear translocation of nuclear factor kappa B (NF-κB) to promote apoptosis. Hence, useful therapeutic approaches to slow down the course of prion disease development should control early inflammatory responses to suppress NFAT signaling. Here we used a hamster model of prion diseases to test, for the first time, the neuroprotective and NFAT-suppressive effect of a second-generation semisynthetic tetracycline derivative, minocycline, versus a calcineurin inhibitor, FK506, with known NFAT suppressive activity. Our results indicate that prolonged treatment with minocycline, starting from the presymptomatic stage of prion disease was more effective than FK506 given either during the presymptomatic or symptomatic stage of prion disease. Specifically, minocycline treatment reduced the expression of the astrocyte activation marker glial fibrillary acidic protein and of the microglial activation marker ionized calcium-binding adapter molecule-1, subsequently reducing the level of proinflammatory cytokines interleukin 1β and tumor necrosis factor-α. We further found that minocycline and FK506 treatment inhibited mitogen-activated protein kinase p38 phosphorylation and NF-κB nuclear translocation in a caspase-dependent manner, and enhanced phosphorylated cyclic adenosine monophosphate response element-binding protein and phosphorylated Bcl2-associated death promoter levels to reduce cognitive impairment and apoptosis. Taken together, our results indicate that minocycline is a better choice for prolonged use in prion diseases and encourage its further clinical development as a possible treatment for this disease. [ABSTRACT FROM AUTHOR]

Estrogen biosynthesis is catalyzed by the Aromatase (P450arom), which is derived from CYP19A1. We investigated the relationship between actin filament re- arrangement, CYP19A1 expression and estradiol bio-synthesis in bovine granulosa cells in vitro. Both bovine fibroblasts and granulosa cells were starved in serum-free culture medium for 24 hours. Serum-starvation disassembled stress fibers in fibroblasts, but not in granulosa cells. Additionally we added Y27632 and CB to medium to de-polymerize the actin filaments, while LPA and insulin were used to re-polymerize actin filaments. A real-time RT-PCR analysis revealed that, FSH induced transcription of CYP19A1 mRNA encoded aromatase was inhibited significantly as actin filaments were de-polymerized by both Y27632 and CB, whereas, restored as actin filaments were re-polymerized by both LPA and insulin. However, further study shows that, statistically there were no differences in the expression of aromatase proteins analyzed by western-blot, during the process of actin filament rearrangement. ARIA analysis also indicated that the secretions of estradiol by bovine granulosa cells were not changed significantly. The results suggested that serum-starvation could not induce actin filaments depolymerization in bovine granulosa cells, while chemically induced actin filament rearrangement influenced the expression of aromatase in mRNA level. But there were no differences in protein level and biological activity of bovine granulosa cells in vitro. [ABSTRACT FROM AUTHOR]

The present study was designed to establish transgenic Eimeria mitis (tE. mitis) expressing chicken interleukin-4 (ChIL-4) and further exploitation of tE. mitis as a novel vaccine vector to control coccidiosis. For this purpose we compared the clinico-hematological alterations induced by wild type and tE. mitis carrying ChIL- 4 in broilers birds. Wild type E. mitis (wE. mitis) oocysts were nucleofected with double cassette vector and transgenic oocysts were propagated for stable transfection. Stability of the transfected E. mitis was observed by fluorescent microscopy and PCR analysis revealed the appearance of 411bp band suggestive of presence of IL-4 into the genome of tE. mitis. Birds inoculated with transgenic EmiChIL-4 excreted fewer oocysts and fecundity potential of tE. mitis turned out to be significantly lower than that of the wild type parent strain. Moderate clinical and behavioral signs such as restlessness, diarrhea, emaciation, decreased feed intake and loss of body weight was observed in birds inoculated with wE. mitis oocysts. The erythrocyte counts, Hb conc, PCV and MCHC decreased in birds infected with wE. mitis as compared to those infected with tE. mitis. The total leukocyte count including heterophils, eosinophil and basophils increased while lymphocytes were decreased in birds inoculated with wE. mitis as compared to birds in control group and those infected with tE.mitis. It was concluded that tE. mitis incorporated with ChIL-4 functions well as an adjuvant, conferring reduced fertility and compromised pathogenicity of tE. mitis. This discrimination, may be applied as a potential vaccine vector to control coccidiosis as well as pathogens from which antigens are expressed by tE. mitis. [ABSTRACT FROM AUTHOR]

A captive 8 yr old male bottlenose dolphin Tursiops truncatus succumbed to septicemia with multisystemic inflammation including suppurative enteritis, encephalitis, and pneumonia with chronic pancreatitis. A pure culture of beta-hemolytic, catalase- and oxidase-negative, Gram-positive cocci was isolated from the hilar lymph nodes and pancreas. The isolate was identified by 16S rDNA sequencing as Streptococcus iniae. Histological examination of the digestive system revealed a mixed infection of both bacteria and fungus. Recognized as a pathogen in fish, dolphins, and humans, this is the first report of S. iniae in a dolphin in mainland China. As the number of managed animals in oceanariums is increasing, so is the frequency of contact with fish used as food for marine mammals and humans, highlighting the importance of education and appropriate personal protective protocols to minimize the risk of transmission. An understanding of marine mammal infectious disease organisms is essential to ensuring the health of marine mammals and humans coming into contact with such animals and their food. This study illustrates a systematic clinical, microbiological, and pathological investigation into a septicemic bottlenose dolphin infected with S. iniae. Our findings provide useful information for those involved in the diagnosis and control of infectious diseases in marine mammals and offer insight into an important zoonotic pathogen.