Seewis virus, a genetically distinct hantavirus in the Eurasian common shrew (Sorex araneus)

More than 20 years ago, hantaviral antigens were reported in tissues of the Eurasian common shrew (Sorex araneus), Eurasian water shrew (Neomys fodiens) and common mole (Talpa europea), suggesting that insectivores, or soricomorphs, might serve as reservoirs of unique hantaviruses. Using RT-PCR, sequences of a genetically distinct hantavirus, designated Seewis virus (SWSV), were amplified from lung tissue of a Eurasian common shrew, captured in October 2006 in Graubünden, Switzerland. Pair-wise analysis of the full-length S and partial M and L segments of SWSV indicated approximately 55%–72% similarity with hantaviruses harbored by Murinae, Arvicolinae, Neotominae and Sigmodontinae rodents. Phylogenetically, SWSV grouped with other recently identified shrew-borne hantaviruses. Intensified efforts are underway to clarify the genetic diversity of SWSV throughout the geographic range of the Eurasian common shrew, as well as to determine its relevance to human health

Borna disease virus antigen distribution in naturally infected bicolored white-toothed shrews, Crocidura leucodon, supporting its role as reservoir host species

Borna Disease is a severe, immunopathological disorder of the central nervous system, caused by infection with Borna Disease Virus (BDV). The main known naturally affected animal species in endemic areas in central Europe are horses and sheep[24]. In this study we present evidence of shrew mice (Crocidura leucodon) as a vector of BDV. The widespread presence of viral antigen and –RNA in the organs of this animal species without producing pathological lesions differs from the classical hosts such as equines, small ruminants and other domestic animals naturally infected with BDV. The detection of BDV in the shrew mice was achieved by immunohistochemistry and by TaqMan® Real Time RT-PCR. RT-PCR mplification products were sequenced, and the sequences were compared with those from horses and sheep originating from the same geographical region, which had died from Borna Disease (BD)

Le categorie geografiche di Giorgio Spinelli

La sezione "Energia e attività economiche", inserita nel volume "Le categorie geografiche di Giorgio Spinelli" ospita una selezione di lavori orientati all'analisi dell'evoluzione dei sistemi energetici, alle previsioni dei fabbisogni ed ai modi per soddisfare tali fabbisogni, allo sfruttamento delle risorse naturali, nonché ai rapporti tra industria e territorio

AUTOIMMUNE THROMBOCYTOPENIC PURPURA IN PREGNANCY: MATERNAL RISK FACTORS PREDICTIVE OF NEONATAL THROMBOCYTOPENIA

Pregnancy in ATP women is not unusual. The problem of this association concerns the possibility of disease transmission to the fetus due to the crossing of maternal antiplatelet antibodies through the placenta. Maternal risk factors predictive of neonatal thrombocytopenia, can be identified as follows: severe thrombocytopenia, previous splenectomy, high titre of PA-IgG and/or SPB-IgG. In 63 pregnancies in ATP patients, we have evaluated whether the above maternal risk factors, considered in the third trimester, can provide useful criteria for the prediction of neonatal thrombocytopenia. In the third trimester, the distribution of maternal risk factors was as follows: 0 in 7 cases, 1 in 27 cases, 2 in 15 cases, 3 in 12 cases, 4 in 2 cases. From a statistical evaluation, the neonatal platelet values and the maternal risk factors seem inversely correlated (r -0.437; p = 0.0005). In particular, neonatal and maternal platelet count correlated positively (r = 0.249; p = 0.025); moreover, neonatal platelet count correlated negatively with Splenectomy (r = -0.209; p = 0.05), PA-IgG (r = -0.401; p < 0.0005) and SPB-IgG (r = -0.338; p < 0.005). We tried to apply a multiple regression model for all the above parameters which appears statistically significant (p = 0.001); the variability was about 30%. This regression model could be validated if applied to a larger number of cases, and it could represent an alternative to the invasive methods used for the diagnosis of neonatal thrombocytopenia

Real-Time PCR Investigation of Potential Vectors, Reservoirs, and Shedding Patterns of Feline Hemotropic Mycoplasmas▿

Three hemotropic mycoplasmas have been identified in pet cats: Mycoplasma haemofelis, “Candidatus Mycoplasma haemominutum,” and “Candidatus Mycoplasma turicensis.” The way in which these agents are transmitted is largely unknown. Thus, this study aimed to investigate fleas, ticks, and rodents as well as saliva and feces from infected cats for the presence of hemotropic mycoplasmas, to gain insight into potential transmission routes for these agents. DNA was extracted from arthropods and from rodent blood or tissue samples from Switzerland and from salivary and fecal swabs from two experimentally infected and six naturally infected cats. All samples were analyzed with real-time PCR, and some positive samples were confirmed by sequencing. Feline hemotropic mycoplasmas were detected in cat fleas and in a few Ixodes sp. and Rhipicephalus sp. ticks collected from animals but not in ticks collected from vegetation or from rodent samples, although the latter were frequently Mycoplasma coccoides PCR positive. When shedding patterns of feline hemotropic mycoplasmas were investigated, “Ca. Mycoplasma turicensis” DNA was detected in saliva and feces at the early but not at the late phase of infection. M. haemofelis and “Ca. Mycoplasma haemominutum” DNA was not amplified from saliva and feces of naturally infected cats, despite high hemotropic mycoplasma blood loads. Our results suggest that besides an ostensibly indirect transmission by fleas, direct transmission through saliva and feces at the early phase of infection could play a role in the epizootiology of feline hemotropic mycoplasmas. Neither the investigated tick nor the rodent population seems to represent a major reservoir for feline hemotropic mycoplasmas in Switzerland

Quality control of disulfide bond formation in pilus subunits by the chaperone FimC

Type 1 pili from uropathogenic Escherichia coli are filamentous, noncovalent protein complexes mediating bacterial adhesion to the host tissue. All structural pilus subunits are homologous proteins sharing an invariant disulfide bridge. Here we show that disulfide bond formation in the unfolded subunits, catalyzed by the periplasmic oxidoreductase DsbA, is required for subunit recognition by the assembly chaperone FimC and for FimC-catalyzed subunit folding. FimC thus guarantees quantitative disulfide bond formation in each of the up to 3,000 subunits of the pilus. The X-ray structure of the complex between FimC and the main pilus subunit FimA and the kinetics of FimC-catalyzed FimA folding indicate that FimC accelerates folding of pilus subunits by lowering their topological complexity. The kinetic data, together with the measured in vivo concentrations of DsbA and FimC, predict an in vivo half-life of 2 s for oxidative folding of FimA in the periplasm