Bacteria strains with strong virulence were isolated from pond-cultured tilapia in China. They were identified as Streptococcus agalactiae by biochemical assays, and confirmed by 16S ribosomal RNA (rRNA) and group B Streptococcus (GBS)-specific gene cfb analyses. Multiplex polymerase chain reaction (PCR) assay of the alpha C protein (ACP) gene and capsular polysaccharide antigen (cps) gene was employed to identify their molecular serotype (MS). Amplification of the ACP gene produced a 400-bp C alpha protein gene (bca) fragment, suggesting that these isolates belong to MS Ia, Ib or II; amplification of cps produced a 790-bp amplicon, indicating that they belong to MS Ia/III-3. An additional PCR based on nucleotide difference in the cps H-I region of MS Ia and III further suggested that the isolates belong to serotype MS Ia. Moreover, multi-locus sequence typing (MLST) indicated that these strains were of sequence type 7 (ST-7). These results showed that isolates from different regions of China shared the same MS and ST. However, none of the isolated ST-7 GBS corresponded to the capsular serotype, suggesting that these fish GBS possessed specific molecular characteristics not present in human or other animals. Data from this study will facilitate the understanding of epidemiology and nosogenesis of tilapia GBS and the establishment of effective disease prevention methods.

In April 2011, 40% mortality of Largemouth Bass Micropterus salmoides juveniles occurred at a farm of Zhongshan City, Guangdong Province, China. Infected fish became lethargic, exhibited corkscrew and irregular swimming, and developed a distended abdomen and crooked body. Fish began to die within 2 d after the appearance of clinical signs. In order to analyze the pathogeny and diagnose the disease earlier, observation of clinical signs, cell infection, titer calculation, electron microscopy, immersion infection assay for fish, and nucleotide sequence analysis were carried out. Fathead minnow (FHM) cell cultures, inoculated with filtrate of liver and spleen homogenates from the diseased fish, developed the obvious cytopathic effect 46 h after inoculation in the primary culture and 24 h at the first passage. Typical rhabdovirus particles, 115-143 nm in length and 62-78 nm in diameter, were observed in infected FHM cells by direct transmission electron microscopy. The isolated virus produced a titer of 10(7.15) TCID50/mL. Immersion-Fish infected with the virus had similar clinical signs and 80% mortality with 10(2.5) LD50/mL. The data indicated that the rhabdovirus was the lethal pathogeny of the current disease. Based on nucleoprotein-gene nucleotide sequence multiple alignment analysis, the newly isolated virus is a strain of Siniperca chuatsi rhabdovirus (SCRV) under family Rhabdoviridae, which was initially isolated from Mandarin Fish Siniperca chuatsi. Up to the present, at least four virus strains have been isolated from diseased Largemouth Bass, which have had different clinical signs. Comparison of the clinical signs can help in an early diagnosis of the disease.

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In an effort to develop potent antiinflammatory agents, a series of substituted chalcone derivatives was synthesized and evaluated for antiinflammatory activity through monitoring of their ability to inhibit xylene-induced ear edema in mice. Some of the tested compounds exhibited significant activity, and compounds 3f [(E)-1-(2,4-dihydroxyphenyl)-3-(4-dimethylamino)phenyl)prop-2-en-1-one] and 3h [(E)-3-(4-chlorophenyl)-1-(2,4-dihydroxyphenyl)prop-2-en-1-one] showed the highest antiinflammatory activity (62 and 68% inhibition, respectively, 2 h before administration), comparable with or even slightly more potent than the