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We determined the prevalence of infection with lymphocytic choriomeningitis virus (LCMV) among small mammals in northern Italy and analyzed long-term dynamics of LCMV in a rodent population in the province of Trento. LCMV is circulating among the most widespread and common wild rodent species in this area (Apodemus flavicollis, Myodes glareolus, and Microtus arvalis); overall prevalence is 6.8%. During 2000-2006, intensive monitoring of LCMV in a population of yellow-necked mice (A. flavicollis) showed a positive correlation between prevalence of infection and rodent density. At the individual level, weight and sex appeared to correlate with antibody prevalence, which suggests that horizontal transmission of LCMV occurs principally among heavier, older males and occurs during fighting. Isolation and genetic characterization of this virus will be the crucial next steps for a better understanding of its ecology. [ABSTRACT FROM AUTHOR]

Study of seasonal changes in the occurrence of Eimeria spp. in Microtus agrestis, Clethrionomys glareolus and Microtus oeconomus populations in Finland showed distinct seasonal variation in all three host species; the peaks occurred in both prevalence and density of infection in early autumn. The low prevalence and density of eimerian infections before and during the main crash of vole populations in late winter indicate that these organisms, although potentially pathogenic, donot significantly contribute to the drastic decline in cyclic vole populations. [ABSTRACT FROM AUTHOR]

Abstract Hantavirus genome sequences were recovered from tissue samples of Myodes rufocanus, Microtus fortis and Microtus oeconomus captured in the Baikal area of Buryatia, Russian Federation. Genetic analysis of S- and M-segment sequences of Buryatian hantavirus strains showed that Myodes-associated strains belong to Hokkaido virus (HOKV) type while Microtus-associated strains belong to Vladivostok virus (VLAV) type. On phylogenetic trees Buryatian HOKV strains were clustered together with M. rufocanus- originated strains from Japan, China and Far-East Russia (Primorsky region). Buryatian Microtus- originated strains shared a common recent ancestor with M. fortis- originated VLAV strain from Far-East Russia (Vladivostok area). Our data (i) confirm that M. rufocanus carries a hantavirus which is similar to but distinct from both Puumala virus carried by M. glareolus and Muju virus associated with M. regulus, (ii) confirm that M. fortis is the natural host for VLAV, and (iii) suggest M. oeconomus as an alternative host for VLAV.

Abstract Sixty one tissue samples from several rodent species trapped in five provinces of Thailand were examined for the presence of hantaviral markers by enzyme-immunoassay and immunoblotting. Four samples, all from the great bandicoot rat Bandicota indica, were confirmed positive for the hantaviral N-antigen. Two of them were trapped in Nakhon Pathom province, the other two in Nakhon Ratchasima province, approximately 250 km from the other trapping site. When analysed by RT-nested PCR, all four rodents were found positive for the hantaviral S- and M-segment nucleotide sequences. Genetic analysis revealed that the four newly described wild-type strains belong to Thailand hantavirus. On the phylogenetic trees they formed a well-supported cluster within the group of Murinae-associated hantaviruses and shared a recent common ancestor with Seoul virus.

The endangered Saimaa ringed seal (Pusa hispida saimensis) is an endemic freshwater subspecies inhabiting Lake Saimaa in Finland. The Baltic ringed seal (Pusa hispida botnica) inhabits the brackish Baltic Sea, which is almost entirely landlocked. Recent research shows that Saimaa and Baltic ringed seals may be genetically even further apart from each other than from other ringed seal subspecies. We documented histologically the integument microstructure of Saimaa and Baltic ringed seals to determine whether the geographic and genetic isolation was manifested as variation in the integument microstructure of these subspecies adapted to icy aquatic environments. The skin structures of these subspecies were similar to those of other phocids. The association of the sweat glands with hair follicles in both subspecies suggested that they were small apocrine sweat glands described previously in terrestrial or aquatic mammals. None of the apocrine glands had large lumina, and some of the ducts were relatively straight and short. Further studies analysing the mode of secretion, for example, apocrine versus eccrine, in the sweat glands are necessary to confirm the types of sweat glands in seals., (© 2024 The Author(s). Anatomia, Histologia, Embryologia published by Wiley‐VCH GmbH.)

The intracranial arterial vascularization of the Saimaa ringed seals (Pusa hispida saimensis; Nordquist, 1899) and Baltic ringed seals (Pusa hispida botnica; Gmelin, 1788) disclosed patterns of anatomical architecture comparable to that of other pinniped species. Arterial silicone casts on skull scaffolds, and magnetic resonance imaging (MRI) showed that the besides joining the caudal communicating arteries upon entering the cerebral arterial circle, the bilateral internal carotid arteries bifurcated as laterally oriented rostral choroidal arteries and rostral cerebral arteries. The latter arteries almost immediately gave off the laterally oriented middle cerebral arteries. Numerous individual variations were evident in differences in the exact branching sites of bilateral vessels or the size or number of arterial branches. Two Saimaa ringed seals had only a tiny foramen for the left internal carotid artery to enter the intracranial space, and the intracranial part of this vessel was short. It did not reach the cerebral arterial circle. The intracranial part of the right internal carotid artery is bifurcated and also supplied the left side of the cerebral arterial circle. Both specimens had aplasia of the left rostral cerebral artery. The intracranial arterial arrangement of Saimaa and Baltic ringed seals reflects the arterial architecture of this body region in terrestrial mammals with little evidence for aquatic adaptations or changes related to thermoregulation., (© 2023 The Authors. The Anatomical Record published by Wiley Periodicals LLC on behalf of American Association for Anatomy.)

The various models used in gross anatomical studies to improve the visualization of blood vessels differ in the amount of manual labour, cost, equipment and time involved. This study aimed to compare chemical and enzymatic maceration processes for soft-tissue removal from arterial silicone casts on skull scaffolds using ringed seal (Pusa hispida) skull specimens. Both processes produced specimens that covered all anatomical aspects required to visualize the intracranial arterial arrangement on a bone scaffold. Overall, the enzyme maceration process was better for production of such specimens, as this process is easy and safe to perform, is less harmful to the bony parts of the specimen, and the resulting specimens are visually more appealing for display and teaching. Compared with previously published models, the end result varied in the amount of dissolved bone tissue and the visual presentation of the model., (© 2023 The Authors. Anatomia, Histologia, Embryologia published by Wiley-VCH GmbH.)

Background and Objective: Consensus on management of pelvic sentinel lymph nodes (PSLNs) has not been reached and thus the extent of sentinel lymph node biopsy (SLNB) of the groin in melanoma patients varies among centers and surgeons. Lymphatic drainage to PSLNs is often identified in, but the diagnostic and clinical relevance of PSLNs has been debated. Our aim was to determine if the presence of PSLNs affected recurrence or survival rates in patients with melanoma in the lower extremities., Methods: This retrospective study consisted of 702 patients with cutaneous melanoma operated between 2005 and 2018. Of these, 134 patients with melanoma in the lower extremities were included in the study. Images of lymphoscintigraphy and SPECT-CT studies were thoroughly observed together with surgery reports to define the status of SLNs., Results: Overall, 85 of 134 patients went through SLNB and 28 of them had PSLN identified. Two had their PSLN removed, which led 26 patients with PSLN to be compared to the 57 who did not have PSLN identified. We did not find statistically significant differences in overall recurrence (26.9% versus 28.0%, p = 1.00), regional nodal recurrence (11.5% versus 15.8%, p = 0.67), local or in-transit recurrence (19.2% versus 8.8%, p = 0.17), or distant recurrence rates (15.4% versus 19.3%, p = 0.66). Disease-free survival did not differ between the groups (median 23.0 (IQR 15.0-39.0) versus 19.0 (IQR 10.3-61.8) months, p = 0.82). Likewise, there was no statistically significant difference in melanoma-specific 5-year survival (78.6% versus 87.2%, p = 0.42)., Conclusions: We did not find more frequent recurrence, shorter disease-free survival, or poorer melanoma-specific survival in patients with drainage to PSLN. Our findings strengthen the evidence that PSLNs should not be routinely biopsied if they are not the first-tier nodes.

Identifying factors that drive infection dynamics in reservoir host populations is essential in understanding human risk from wildlife-originated zoonoses. We studied zoonotic Puumala orthohantavirus (PUUV) in the host, the bank vole ( Myodes glareolus ), populations in relation to the host population, rodent and predator community and environment-related factors and whether these processes are translated into human infection incidence. We used 5-year rodent trapping and bank vole PUUV serology data collected from 30 sites located in 24 municipalities in Finland. We found that PUUV seroprevalence in the host was negatively associated with the abundance of red foxes, but this process did not translate into human disease incidence, which showed no association with PUUV seroprevalence. The abundance of weasels, the proportion of juvenile bank voles in the host populations and rodent species diversity were negatively associated with the abundance index of PUUV positive bank voles, which, in turn, showed a positive association with human disease incidence. Our results suggest certain predators, a high proportion of young bank vole individuals, and a diverse rodent community, may reduce PUUV risk for humans through their negative impacts on the abundance of infected bank voles.

The anatomical architecture of the hip and stifle joints of the Saimaa ringed seal was determined by dissection to be similar to that of the Baltic ringed seal. There was no ligament of the femoral head in the hip joint. The lateral side of the stifle joint lacked a collateral ligament but the collateral ligament on the medial side was of considerable size. The medial meniscus was larger and thicker than the lateral meniscus. The asymmetrical anatomical architecture allows for much lateral movement during aquatic motion, but it is poorly adapted to terrestrial locomotion., (© 2021 Wiley-VCH GmbH.)

In contrast to medical education, information on the use of arts as a learning approach is scarce in veterinary anatomy. The aim of this prospective, questionnaire-based study was to survey students' use of drawing in various aspects of veterinary anatomy learning (self-study, examinations, preparation for, and reflection on cadaver dissection). The quantitative data showed that first-year students with artistic preferences used drawing significantly more often in most aspects of anatomy learning than students with no such preferences, apart from the reported use of drawing in examinations and for reflection after cadaver dissection. The lack of significant correlations of the reported use of drawing in examinations with any other study variable provided support for the author's observation that student-generated drawings are not as commonly used in examinations as previously. In contrast to the study hypothesis, previous university studies did not correlate significantly with any aspect of the use of drawing in anatomy learning. None of the reported uses of drawing addressed the benefits of drawing in learning the comparative anatomy of animal species, a characteristic distinguishing veterinary anatomy from human anatomy. Qualitative student feedback indicated that encouragement and teacher-produced images would increase the use of drawing as a learning approach even if the implementation of drawing into the curriculum is not feasible. Conclusions from this study were implemented through self-directed learning in anatomy courses that replaced the canceled cadaveric dissections during the COVID-19 outbreak and also through the ongoing drawing workshops to further advance the use of drawing in veterinary anatomy learning., (© 2020 American Association for Anatomy.)