Notes

Catalytic, Enantioselective Syn-Oxyamination associated with Alkenes.
Anti-Ehrlichia spp. selleckchem antibodies were detected in five/12 (41.7 %) horses by IFA, with antibody titers ranging from 40 to 160. All horse DNA samples were negative for the 16S rRNA, dsb, groEL and sodB of Ehrlichia spp. One A. sculptum female was positive to all target genes of Ehrlichia. This tick was parasitizing an Ehrlichia-seropositive horse with antibody titer of 80. Nucleotide sequences of 16S rRNA, dsb, groEL and sodB genes showed close relationship with different strains of Ehrlichia detected in wild mammals, Amblyomma ticks and horses from Brazil and Argentina. Detection of anti-Ehrlichia sp. antibodies suggests that horses have been exposed to an ehrlichial agent in the Pantanal. Future studies on Ehrlichia infection should be carried out to better elucidate and to bring new information about equine ehrlichiosis, since these animals are important hosts of ticks in the Brazilian Pantanal wetlands.Age-related hearing loss (ARHL), also known as presbycusis, is a widespread and debilitating condition impacting many older adults. Conventionally, researchers utilize mammalian model systems or human cadaveric tissue to study ARHL pathology. Recently, the zebrafish has become an effective and tractable model system for a wide variety of genetic and environmental auditory insults, but little is known about the incidence or extent of ARHL in zebrafish and other non-mammalian models. Here, we evaluated whether zebrafish exhibit age-related loss in auditory sensitivity. The auditory sensitivity of adult wild-type zebrafish (AB/WIK strain) from three adult age subgroups (13-month, 20-month, and 37-month) was characterized using the auditory evoked potential (AEP) recording technique. AEPs were elicited using pure tone stimuli (115-4500 Hz) presented via an underwater loudspeaker and recorded using shielded subdermal metal electrodes. Based on measures of sound pressure and particle acceleration, the mean AEP thresholds of 37-month-old fish [mean sound pressure level (SPL) = 122.2 dB ± 2.2 dB SE re 1 μPa; mean particle acceleration level (PAL) = -27.5 ± 2.3 dB SE re 1 ms-2] were approximately 9 dB higher than that of 20-month-old fish [(mean SPL = 113.1 ± 2.7 dB SE re 1 μPa; mean PAL = -37.2 ± 2.8 dB re 1 ms-2; p = 0.007)] and 6 dB higher than that of 13-month-old fish [(mean SPL = 116.3 ± 2.5 dB SE re 1 μPa; mean PAL = -34.1 ± 2.6 dB SE re 1 ms-2; p = 0.052)]. Lowest AEP thresholds for all three age groups were generally between 800 Hz and 1850 Hz, with no evidence for frequency-specific age-related loss. Our results suggest that zebrafish undergo age-related loss in auditory sensitivity, but the form and magnitude of loss is markedly different than in mammals, including humans. Future work is needed to further describe the incidence and extent of ARHL across vertebrate groups and to determine which, if any, ARHL mechanisms may be conserved across vertebrates to support meaningful comparative/translational studies.The mechanism of tinnitus, the perception of sound in the absence of acoustic stimulation, remains as yet unknown. It has been proposed that tinnitus is caused by altered spontaneous activity in the auditory pathway following cochlear damage in combination with inadequate gating at the level of the auditory thalamus, the medial geniculate nucleus (MGN). To investigate this further we made electrophysiological recordings in MGN of guinea pigs (n = 9) with and without tinnitus after acoustic trauma (continuous loud tone at 10 kHz, 124 dB SPL for 2 h). Parameters of interest were spontaneous tonic and burst firing. After acoustic trauma, 5 out of 9 guinea pigs developed signs of tinnitus as determined by the gap prepulse inhibition of acoustic startle. Spontaneous firing rates were significantly increased in the tinnitus animals as compared to the non-tinnitus animals and this change was specific to pure-tone responsive MGN neurons. However, burst firing parameters, including number of bursts per minute, burst duration, number of spikes in each burst, and percentage of spikes occurring in a burst, were not different between tinnitus and non-tinnitus animals. In addition, our data showed a strong dependence of spontaneous firing rates with heart rate, which implies that monitoring physiological status in animals is pertinent to obtaining reliable data when recording at higher levels of the auditory pathway. Our results suggest that increases in the tonic spontaneous fining rate of pure-tone responsive MGN neurons but not changes in burst firing parameters, are a robust neural signature of tinnitus in anaesthetised animals.There is currently a strong scientific consensus that recent global change of climate, including the global warming, seriously damage ecosystems of both lands and oceans. Here, I review recent drastic northern expansion of distribution of tropical land hermit crabs (Coenobita) into temperate Japan. Seto Marine Biological Laboratory of Kyoto University has a long history (97 years) and has been conducting various programs of long-term monitoring survey on coastal biota. A part of the results is also introduced here. Seventeen species of land hermit crabs are known from tropical regions worldwide, and seven species are known in Japan, which are mainly distributed in tropical region of Japan. Recent intensive studies on coastal areas of Japan have shown that many juveniles and small individuals of land hermit crabs are found during warm season in temperate regions. The finding of the species that were identified by DNA analysis as Coenobita rugosus and C. purpureus might be an indication for the global warming effect. Further, I here introduce the model of northern limit of distribution proposed by Gorodkov (1986) which explains change of detailed structure of population toward the limit of distribution. Moreover, I here propose the model of stages of adaptation of tropical species to temperate zone through ecological and evolutional times. These two models are useful and helpful to understand the things happen in populations in the limit of distribution and, therefore, useful for conservation of species and biological communities.
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