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Growing to lengths and weights exceeding 1.5 m and 45 kg, the hump-backed mahseer fish of the Western Ghats biodiversity hotspot, India, is an iconic, mega-faunal species that is globally recognized as a premier freshwater game fish. Despite reports of their high extinction risk, conservation approaches are currently constrained by their lack of valid taxonomic identity. Using an integrative approach, incorporating morphology, molecular analysis and historical photographs, this fish can now be revealed to be conspecific with Tor remadevii, a species lacking a common name, that was initially, but poorly, described in 2007 from the River Pambar, a tributary of the River Cauvery in Kerala. Currently known to be endemic and restricted to the River Cauvery basin in the Western Ghats, T. remadevii is distinguished from congeners by its prominent hump originating above the pre-opercle and extending to the origin of the dorsal fin, a well-developed mandible resulting in a terminal or slightly superior mouth position, and the dorsal orientation of the eyes. While body colouration varies (silver, bronze, greenish) and is not considered a reliable diagnostic character, orange coloration of the caudal fin (sometimes extending to all fins) is considered a consistent characteristic. Having been first brought to the attention of the scientific community in 1849, and the recreational angling (game fishing) community in 1873, it has taken over 150 years to finally provide this iconic fish with a valid scientific name. This taxonomic clarity should now assist development and delivery of urgent conservation actions commensurate with their extinction risk., Competing Interests: The authors declare that no competing interests exist. Views and opinions expressed by the authors are their own and do not in any way represent those of the organization(s) they represent.

Diets rich in n-3 polyunsaturated fatty acids (PUFAs) are associated with suppression of cell-mediated immune responses, but the mechanisms are unclear. We hypothesized that n-3 PUFAs can inhibit the function of human antigen-presenting cells. A prerequisite for this role of blood monocytes is the cell surface expression of major histocompatibility complex (MHC) class II molecules [human leukocyte antigen (HLA)-DR, -DP, and -DQ], aided by the presence of intercellular adhesion molecule-1 (ICAM-1) and leukocyte function associated antigens 1 and 3. We showed previously that the n-3 PUFA eicosapentaenoic acid (EPA) inhibits the expression of HLA-DR on unstimulated human monocytes in vitro, but that docosahexaenoic acid (DHA) enhances its expression. However, both n-3 PUFAs suppress the expression of HLA-DR, HLA-DP, and ICAM-1 on interferon-gamma-activated monocytes. We also established that dietary fish-oil supplementation can inhibit the expression of these surface molecules on circulating human monocytes. We subsequently showed that when EPA and DHA were combined in the same ratio as is commonly found in fish-oil-supplement capsules (3:2), there was no significant effect in vitro on the expression of HLA-DR on unstimulated monocytes, but the expression on activated monocytes remained significantly inhibited. In the same in vitro system, the ability of activated monocytes to present antigen to autologous lymphocytes was significantly reduced after culture with the combined n-3 PUFAs. These findings provide one potential mechanism for the beneficial effect of fish oil in the treatment of rheumatoid arthritis, a disorder associated with elevated expression of MHC class II and adhesion molecules on monocytes present within affected joints.

N-3 polyunsaturated fatty acid (PUFA)-rich diets are associated with suppression of cell-mediated immune responses, but the mechanisms are unclear. Specific immune responses are initiated by antigen-presenting cells (APC). We have previously shown in vitro that the n-3 PUFA, eicosapentaenoic acid (EPA), inhibits the expression of HLA-DR, an MHC class II molecule required for normal APC function on human blood monocytes. In contrast, docosahexaenoic acid (DHA) enhanced the expression of this molecule on unstimulated monocytes, but both n-3 PUFA suppressed its expression on interferon-gamma (IFN-gamma)-activated monocytes. In the present study we show that when EPA and DHA were combined at the same ratio as is commonly found in fish oil supplement capsules (3:2) there was no significant effect in vitro on the expression of HLA-DR on unstimulated monocytes, but the expression on IFN-gamma-activated monocytes remained significantly inhibited. In the same in vitro system a significant reduction in the ability of IFN-gamma-activated monocytes to present tetanus toxoid antigen to autologous lymphocytes was observed following culture with the combined n-3 PUFA. These findings support previous animal studies which suggest that n-3 PUFA can inhibit the antigen-presenting function of mononuclear phagocytes.

Diets rich in (n-3) polyunsaturated fatty acids (PUFA) are associated with suppression of the immune system, but the mechanisms are unclear. Specific immune responses are initiated by antigen-presenting cells. This study examines the in vitro effect of the (n-3) PUFA eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the expression of cell surface molecules required for normal antigen-presenting cell function on human blood monocytes. Monocytes were incubated with or without EPA or DHA for 48 h at 37 degrees C. Following incubation, expression of major histocompatibility complex (MHC) class II molecules (HLA-DR, -DP and -DQ) and adhesion molecules [intercellular adhesion molecule-1 (ICAM-1) and leucocyte function associated antigen-1] was quantified by flow cytometry. In the presence of EPA alone there was a significantly lower median intensity of expression of HLA-DR and ICAM-1 relative to incubations without EPA. In contrast, significantly greater median intensities of expression of HLA-DR and -DP were observed following incubation with DHA. In parallel experiments, where monocytes were simultaneously activated by the addition of interferon-gamma to the cultures, median expression intensities of HLA-DR, -DP and ICAM-1 were significantly lower in the presence of either EPA or DHA compared with incubations without the (n-3) PUFA. These findings support previous animal studies that suggest that (n-3) PUFA can influence immune reactivity by modulating antigen-presenting cell function.

Flow cytometry, combined with fluorescently labelled monoclonal antibodies, offers advantages of speed and sensitivity for the detection of specific pathogenic bacteria in foods. We investigated the detection of Salmonella typhimurium in eggs and milk. Using a sample clearing procedure, we determined that the detection limit was on the order of 10(3) cells per ml after a total analysis time of 40 min. After 6 h of nonselective enrichment, the detection limits were 10 cells per ml for milk and 1 cell per ml for eggs, even in the presence of a 10,000-fold excess of Escherichia coli cells.

The motion of the amphibian eardrum under free-field acoustic stimulation was investigated using time-averaged holography. We show that the amplitude is linearly related to sound pressure up to +/- 1000 nm. The frequency response of the eardrum shows broad resonance characteristics with a main peak between 1200-2200 Hz. The velocity of the tympanic membrane's motion at its resonance frequency matches the acoustic velocity of air particles. The resonance characteristics of the eardrum are also revealed by white noise stimulation. The power spectrum obtained by Fourier transformation of the autocorrelation of the response to noise resembles closely that obtained by holography.