A new RT-PCR test was developed for the diagnosis of chronic bee paralysis virus (CBPV) infection. Used in parallel with an experimental infection test, the RT-PCR test was less fastidious and allowed the detection of latent CBPV infection in colonies. The new test is based on the fact that clinical CBPV infections (but not latent infections) yield a high viral antigen load that can be easily revealed using the agarose gel immunodiffusion (AGID) test. The combination of the AGID and the RT-PCR tests allowed us to characterise the CBPV status of hives from various apiaries in France as non infected, latently infected or clinically infected. The RT-PCR test proved highly sensitive for detecting inapparent infections. It may be a useful tool for studying the epidemiology of the disease. chronic bee paralysis virus (CBPV) / latent infection / RT-PCR diagnosis / characterisation of CBPV status / Apis mellifera

After 10 wk of feeding an experimental diet enriched with (n-3) polyunsaturated fatty acids (PUFA), i.e., eicosapentaenoic acid [EPA, 20:5(n-3)] and [DHA, 22:6(n-3)] (EPAX), blood pressure in spontaneously hypertensive rats (SHR), but not in normotensive Wistar-Kyoto (WKY) rats was reduced relative to rats fed an unsupplemented control diet. Concanavalin A-stimulated T-cell proliferation was diminished in both strains of rats fed the PUFA/EPAX diet. The experimental diet lowered secretion of interleukin-2 in SHR, but not in WKY rats compared with rats fed the control diet. To determine whether there was a defect in calcium homeostasis in T cells during hypertension, we employed the following agents: caffeine, which recruits calcium from the cytosolic Ca(2+)-induced Ca(2+)-release pool; ionomycin, which at low concentrations opens calcium channels; and thapsigargin (TG), which mobilizes [Ca(2+)]i from the endoplasmic reticulum (ER) pool. Caffeine-induced increases in [Ca(2+)]i were not modified by the PUFA/EPAX diet. The ionomycin-induced increases in [Ca(2+)]i in T cells from SHR were greater than in those from WKY rats; consumption of the PUFA/EPAX diet did not modify Ca(2+) influx in cells of either strain. The TG-induced increases in [Ca(2+)]i in T cells from SHR were greater than those in cells from WKY rats. Interestingly, consumption of the experimental diet reduced TG-evoked increases in [Ca(2+)]i in T cells from SHR and increased those in T cells from WKY rats, indicating that the PUFA/EPAX diet could reverse the calcium mobilization from the ER pool in T cells. These results suggest that (n-3) PUFA exert antihypertensive effects and modulate T-cell calcium signaling during hypertension in rats.

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