Antibiotic susceptibility of bacteria isolated from infections in cats and dogs throughout Europe (2002–2009)

A monitoring program of the pre-treatment susceptibility of clinical isolates of bacteria from diseased dogs and cats was active between the years 2002 and 2009. Susceptibility of each isolated strain to a panel of nine antibiotics (amoxicillin/clavulanic acid, ampicillin, penicillin, clindamycin, doxycycline, enrofloxacin, marbofloxacin, trimethoprim and trimethoprim/sulfamethoxazole) was assessed. The Minimum Inhibitory Concentration (MIC) of marbofloxacin was also determined by a standardized microdilution technique following CLSI recommendations. In total, 1857 bacterial strains were collected throughout Europe from cases of otitis, respiratory, urinary and dermatological infections. Although bacterial susceptibility varied for each of the antibiotics within the panel, patterns of susceptibility were similar to those described in the literature for comparable time periods and geographical areas. With a clinical resistance varying from 0 to 14.48% against the isolated strains, marbofloxacin susceptibility was very high and remains an effective antibiotic for the treatment of otitis, urinary, respiratory and dermatological infections in companion animals.     

Resonant optical antennas

We have fabricated nanometer-scale gold dipole antennas designed to be resonant at optical frequencies. On resonance, strong field enhancement in the antenna feed gap leads to white-light supercontinuum generation. The antenna length at resonance is considerably shorter than one-half the wavelength of the incident light. This is in contradiction to classical antenna theory but in qualitative accordance with computer simulations that take into account the finite metallic conductivity at optical frequencies. Because optical antennas link propagating radiation and confined/enhanced optical fields, they should find applications in optical characterization, manipulation of nanostructures, and optical information processing.     

Epidemiological characteristics of rabies in South Korea from 1993 to 2001

In the nine years from 1993 to 2001, 210 cases of rabies were recorded in domestic animals in South Korea; 115 cattle, 94 dogs and one farmed deer were affected. The annual incidence of rabies cases increased to a peak of 64 in 1998, and then decreased to about 30 cases per year. The cases were confined to the northern part of Kyounggi and Kangwon provinces. One hundred and forty-six cases (69.5 per cent) occurred in Kyounggi and 64 cases (30.5 per cent) in Kangwon province, and about 82 per cent of them were confined to two counties in Kyounggi province (29 per cent in Paju and 28.1 per cent in Younchun) and to Chulwon county in Kangwon province (25.2 per cent). However, over several years the outbreaks gradually moved south and east in both Kyounggi and Kangwon provinces. There were more rabies cases in cattle than in dogs, suggesting that the disease is transmitted by the sylvatic cycle. To investigate the relationship between rabies in domestic animals and wild animals, 107 wild animals, including Korean raccoon dogs, badgers, weasels and feral cats, were tested for rabies; 21 of the 67 Korean raccoon dogs tested (31 per cent) were infected. The cases in domestic animals were most common in winter, from December to February, and least common in summer, from June to September.     

Preferential expression of L-type amino acid transporter 1 in ameloblasts during rat tooth development

Certain amino acid transport systems play an important role in supplying organic nutrients to each cell and for cell proliferation during tooth development. However, the mechanisms responsible for such actions are unclear. This study demonstrated for the first time that LAT1 and 4F2hc are expressed during tooth development in prenatal and postnatal rats, and that the transporters show cell-specific expression in ameloblasts, which are the epithelium-derived dental cells. LAT1 and 4F2hc expression was not observed in other dental cells of the developing teeth such as odontoblasts and cementoblasts. Overall, these results suggest that LAT1 and 4F2hc might play an important role in enamel formation.     

Ecological fitness and strategies of adaptation of Bartonella species to their hosts and vectors

Bartonella spp. are facultative intracellular bacteria that cause characteristic host-restricted hemotropic infections in mammals and are typically transmitted by blood-sucking arthropods. In the mammalian reservoir, these bacteria initially infect a yet unrecognized primary niche, which seeds organisms into the blood stream leading to the establishment of a long-lasting intra-erythrocytic bacteremia as the hall-mark of infection. Bacterial type IV secretion systems, which are supra-molecular transporters ancestrally related to bacterial conjugation systems, represent crucial pathogenicity factors that have contributed to a radial expansion of the Bartonella lineage in nature by facilitating adaptation to unique mammalian hosts. On the molecular level, the type IV secretion system VirB/VirD4 is known to translocate a cocktail of different effector proteins into host cells, which subvert multiple cellular functions to the benefit of the infecting pathogen. Furthermore, bacterial adhesins mediate a critical, early step in the pathogenesis of the bartonellae by binding to extracellular matrix components of host cells, which leads to firm bacterial adhesion to the cell surface as a prerequisite for the efficient translocation of type IV secretion effector proteins. The best-studied adhesins in bartonellae are the orthologous trimeric autotransporter adhesins, BadA in Bartonella henselae and the Vomp family in Bartonella quintana. Genetic diversity and strain variability also appear to enhance the ability of bartonellae to invade not only specific reservoir hosts, but also accidental hosts, as shown for B. henselae. Bartonellae have been identified in many different blood-sucking arthropods, in which they are typically found to cause extracellular infections of the mid-gut epithelium. Adaptation to specific vectors and reservoirs seems to be a common strategy of bartonellae for transmission and host diversity. However, knowledge regarding arthropod specificity/restriction, the mode of transmission, and the bacterial factors involved in arthropod infection and transmission is still limited.