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1.
Sci Rep ; 10(1): 11437, 2020 07 10.
Article in English | MEDLINE | ID: mdl-32651419

ABSTRACT

Anthropogenic linear features facilitate access and travel efficiency for predators, and can influence predator distribution and encounter rates with prey. We used GPS collar data from eight wolf packs and characteristics of seismic lines to investigate whether ease-of-travel or access to areas presumed to be preferred by prey best explained seasonal selection patterns of wolves near seismic lines, and whether the density of anthropogenic features led to functional responses in habitat selection. At a broad scale, wolves showed evidence of habitat-driven functional responses by exhibiting greater selection for areas near low-vegetation height seismic lines in areas with low densities of anthropogenic features. We highlight the importance of considering landscape heterogeneity and habitat characteristics, and the functional response in habitat selection when investigating seasonal behaviour-based selection patterns. Our results support behaviour in line with search for primary prey during summer and fall, and ease-of-travel during spring, while patterns of selection during winter aligned best with ease-of-travel for the less-industrialized foothills landscape, and with search for primary prey in the more-industrialized boreal landscape. These results highlight that time-sensitive restoration actions on anthropogenic features can affect the probability of overlap between predators and threatened prey within different landscapes.


Subject(s)
Deer/physiology , Geographic Information Systems , Predatory Behavior/physiology , Wolves/physiology , Animals , Ecosystem , Humans , Seasons
2.
Prev Vet Med ; 117(2): 326-39, 2014 Nov 15.
Article in English | MEDLINE | ID: mdl-25218913

ABSTRACT

In Southwest Alberta, beef cattle and wild elk (Cervus elaphus) have similar habitat preferences. Understanding their inter-species contact structure is important for assessing the risk of pathogen transmission between them. These spatio-temporal patterns of interactions are shaped, in part, by range management and environmental factors affecting elk distribution. In this study, resource selection modeling was used to identify factors influencing elk presence on cattle pasture and elk selection of foraging patches; furthermore, consequences for inter-species disease transmission were discussed. Data on pasture management practices and observations of elk were collected from 15 ranchers during interviews. Pasture use by elk was defined based on telemetry data (from GPS collars deployed on 168 elk in 7 herds) and rancher observations. At the patch scale, foraging patches used by elk were identified by spatio-temporal cluster analysis of telemetry data, whereas available patches were randomly generated outside the area delimited by used patches. For pastures and patches, landscape and human-managed features were characterized using remote sensing data and interviews, respectively. Attributes of available and used pastures (or patches) were compared using resource selection functions, on annual and seasonal (or annual and monthly) time scales. Additionally, intensity of pasture use was modeled using negative binomial regression. Cultivated hay land and mineral supplements were associated with elk presence on cattle pastures, whereas pastures with manure fertilization and higher traffic-weighted road densities were less likely to be used by elk. The effects of landscape (elevation, aspect, water access) and vegetation (forest cover, Normalized Difference Vegetation Index) characteristics on patch selection were consistent with typical elk habitat requirements. The presence of cattle and the traffic-weighted road density were negatively associated with patch selection. The apparent avoidance of cattle by elk reduced the risk of direct transmission of pathogens, except during winter months. However, human-managed features attracting elk to cattle pastures (e.g. hay land and mineral supplements) may increase inter-species pathogen transmission through indirect contacts.


Subject(s)
Animal Husbandry/methods , Cattle Diseases/transmission , Deer/microbiology , Ecosystem , Alberta/epidemiology , Animals , Cattle , Cattle Diseases/epidemiology , Cattle Diseases/microbiology , Seasons , Spatio-Temporal Analysis , Telemetry/veterinary
3.
Dermatology ; 220(2): 138-42, 2010.
Article in English | MEDLINE | ID: mdl-20110633

ABSTRACT

BACKGROUND: Parvovirus B19 is the aetiological agent of erythema infectiosum. The presence of B19 DNA in lesional skin of other cutaneous manifestations has frequently been reported although there is disagreement on the role of the B19 virus in tissues. OBJECTIVES: To investigate the presence of B19 DNA (1) in skin lesions of patients with a described B19-related disease, (2) in skin lesions of B19-unrelated diseases and (3) in healthy skin. METHODS: A total of 121 skin samples were examined for the presence of B19 DNA by PCR assays and peptide-nucleic-acid-based in situ hybridisation techniques. RESULTS: B19 DNA was detected in 11/38 (28.9%) pityriasis lichenoides, 8/30 (26.7%) melanocytic naevi, 5/29 (17.2%) primary melanomas and 6/24 (25.0%) healthy skin biopsies. A difference in B19 DNA prevalence was observed in specimens grouped according to age, irrespective of pathologies. CONCLUSIONS: B19 DNA can be found in skin tissues of patients with pityriasis lichenoides as well as in lesions not related to B19 infection and in healthy controls. B19 DNA can be detected in skin of young subjects in a significantly high rate compared to adults, suggesting that viral persistence may be the usual outcome after primary infection.


Subject(s)
Erythema Infectiosum/virology , Parvovirus B19, Human/isolation & purification , Skin/virology , Adult , Aged , Aged, 80 and over , DNA, Viral/analysis , Female , Humans , Male , Melanoma/virology , Middle Aged , Nevus/virology , Pityriasis Lichenoides/virology , Skin Neoplasms/virology
5.
BJOG ; 116(6): 813-7, 2009 May.
Article in English | MEDLINE | ID: mdl-19432570

ABSTRACT

OBJECTIVE: The purpose of our work was to examine the most reliable laboratory diagnosis of fetal parvovirus B19 infection in hydropic fetuses by evaluating the most appropriate clinical sample and laboratory test. DESIGN: B19 DNA detection in fetal samples and serological signs of B19 infection in the respective mothers. Samples collected between January 2000 and July 2008. SETTING: Microbiology, University of Bologna, Bologna, Italy. SAMPLES: One hundred thirty-five fetal samples (58 fetal cord blood and 77 amniotic fluid samples) and 109 serum samples collected from 109 pregnant women. METHODS: Validated and certified in situ hybridisation assay (ISH) and polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA) were performed on fetal samples to detect B19 DNA. B19-specific antibodies were investigated in maternal serum samples by a commercial enzyme immunoassay. MAIN OUTCOME MEASURES: Parvovirus B19 DNA detection in fetal specimens was analysed in relation to maternal serological signs of infection. RESULTS: Parvovirus B19 DNA was detected in 22.41% of fetal cord blood and 36.36% of amniotic fluid samples. A statistically significant difference was found between DNA detection by ISH (23.70%) and PCR-ELISA (14.81%) (P= 0.004). Only 11.76% of fetuses with virological diagnosis of B19 infection were from women with serological signs of acute/recent B19 infection. CONCLUSIONS: Diagnosis of fetal parvovirus B19 infection cannot always rely on maternal serological investigations but rather on the virological analysis of fetal samples. Both fetal cord blood and amniotic fluid samples are suitable for diagnosis, but the detection of B19 DNA in the cells of amniotic fluid samples by ISH proved to be the most reliable diagnostic system.


Subject(s)
Fetal Diseases/diagnosis , Parvoviridae Infections/diagnosis , Parvovirus B19, Human/isolation & purification , Prenatal Diagnosis/methods , Amniotic Fluid/virology , DNA, Viral/analysis , Enzyme-Linked Immunosorbent Assay/methods , Female , Fetal Blood/virology , Humans , Hydrops Fetalis/virology , In Situ Hybridization/methods , Parvovirus B19, Human/genetics , Polymerase Chain Reaction/methods , Pregnancy
6.
Anal Bioanal Chem ; 394(4): 981-7, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19263042

ABSTRACT

Classification of cervical intraepithelial neoplasia (CIN) lesions in low-grade (CIN1) or high-grade (CIN2-3) ones is crucial for optimal patient management, but current histological diagnosis on bioptic samples is often hampered by inter-observer variability. To allow objective classification, we have exploited the peculiar characteristics of chemiluminescence detection, such as high sensitivity and easy quantification of the luminescence signal, to perform sequentially in the same tissue section both an immunohistochemical quantitative detection of p16(INK4A) (a protein marker of high-grade CIN lesions) and an in situ hybridization for human papillomavirus (generally accepted as a necessary but insufficient cause of cervical carcinoma). Different label enzymes (alkaline phosphatase and horseradish peroxidase) were employed in order to avoid any interference between the two assays, and quantitative chemiluminescence image analysis was used to obtain objective evaluation of sample positivity. The multiplexed method allowed detection of two complementary biomarkers and provided discrimination between different lesions (non-neoplastic, low-grade and high-grade CIN). This assay might thus represent an accurate and objective diagnostic test providing important information for counseling, selection of therapy and follow up after surgical treatment.


Subject(s)
Biomarkers, Tumor/analysis , Cyclin-Dependent Kinase Inhibitor p16/analysis , DNA, Viral/analysis , Luminescent Measurements/methods , Papillomaviridae/genetics , Papillomaviridae/isolation & purification , Uterine Cervical Dysplasia/diagnosis , Female , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Reproducibility of Results , Sensitivity and Specificity , Uterine Cervical Dysplasia/metabolism , Uterine Cervical Dysplasia/pathology
7.
Br J Dermatol ; 156(1): 38-44, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17199564

ABSTRACT

BACKGROUND: The vast majority of studies aimed at detecting human papillomavirus (HPV) DNA in skin cancer have used sensitive polymerase chain reaction (PCR) methods but the PCR technique, despite its high sensitivity, is not suitable to ascertain whether (i) the presence of HPV can be related only to few cells harbouring the virus, (ii) the presence of HPV is due to a tumour surface contamination and (iii) the presence of HPV is localized in cancer cells, rather than in normal keratinocytes present in the tumour biopsy. In a recent work we have found mucosal high-risk (HR) HPV genotypes in primary melanoma by PCR. OBJECTIVES: To localize mucosal HR-HPV nucleic acids and tumoural melanocytic marker in the same sections of primary melanoma samples in order to understand the relationship between HPVs and melanoma cells. METHODS: We have developed a very sensitive method that combines an enzyme-amplified fluorescent in situ hybridization (ISH) for the detection of HPV nucleic acids (types 16 and 18) with a chemiluminescent immunohistochemistry (IHC) method for the detection of the tumoural melanocytic marker HMB-45 sequentially in the same section. Digital images of fluorescent ISH and chemiluminescent IHC were separately recorded, assigned different colours and merged using specific software for image analysis. RESULTS: The combined fluorescent ISH and chemiluminescent IHC demonstrated a sharp colocalization (in the range 60-80%) of HPV nucleic acids and melanoma marker inside the same sections of melanoma biopsies, with a strong specificity and sensitivity. CONCLUSIONS: The strong colocalization of mucosal HR-HPV nucleic acids and HMB-45 melanocytic marker emphasized that viral nucleic acids were specifically present in melanoma cells and supported a possible active role of HPV in malignant melanoma.


Subject(s)
Melanoma/virology , Mouth Neoplasms/virology , Papillomavirus Infections/diagnosis , Adult , Aged , Biopsy/methods , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Immunohistochemistry/methods , In Situ Hybridization/methods , In Situ Hybridization, Fluorescence , Luminescent Measurements , Male , Middle Aged , Mucous Membrane/virology , Papillomaviridae/isolation & purification
8.
J Med Virol ; 77(1): 102-6, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16032717

ABSTRACT

The presence and type of oncogenic papillomavirus (HPV) in classic warty/basaloid vulvar intraepithelial neoplasia and in differentiated vulvar intraepithelial neoplasia and keratinizing vulvar squamous cell carcinoma was investigated using three techniques, that is, histology, in situ hybridization, and PCR-ELISA. HPV typing was performed using in situ hybridization and PCR-ELISA. Differentiated vulvar intraepithelial neoplasia and invasive keratinizing vulvar squamous cell carcinoma proved completely negative for HPV by PCR-ELISA, in situ hybridization, and histologic examination, while in classic vulvar intraepithelial neoplasia, a HPV positivity of 66.1% was found. HPV 16 was the predominant type, with HPV 35, 33, and 52 types found rarely and sometimes together with HPV 16. PCR-ELISA proved to be the most suitable method to detect and type mucosal oncogenic HPVs. The absolute absence of HPV DNA in differentiated vulvar intraepithelial neoplasias and in keratinizing vulvar squamous cell carcinoma suggests a strong HPV-independent pathway of malignant progression to invasive carcinoma.


Subject(s)
Carcinoma, Squamous Cell/virology , Papillomaviridae/classification , Vulvar Neoplasms/virology , Adult , Aged , DNA, Viral/analysis , Enzyme-Linked Immunosorbent Assay , Epithelium/pathology , Female , Humans , Middle Aged , Papillomaviridae/genetics , Papillomaviridae/isolation & purification , Polymerase Chain Reaction
9.
Br J Dermatol ; 152(5): 909-14, 2005 May.
Article in English | MEDLINE | ID: mdl-15888145

ABSTRACT

BACKGROUND: Some studies have shown that cutaneous and mucosal melanoma biopsy specimens harbour human papillomavirus (HPV), suggesting that this virus may play a role in development and progression of the tumour. OBJECTIVES: To investigate the presence of HPV DNA and the prevalence of different high-risk mucosal HPV genotypes in primary melanoma (PM) and in acquired dysplastic melanocytic naevi (ADMN). METHODS: Fifty-one PMs from 18 men and 33 women (median age 55.5 years), 33 ADMN from 15 men and 18 women (median age 35.1 years) and 20 control skin samples from nine men and 11 women (median age 43.5 years) were studied. All diagnoses were made after histological analysis. HPV DNA analysis was made using two different polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA) methods, namely MY-PCR and GP-PCR. RESULTS: Using GP-PCR, mucosal HPVs were detected in 14 PMs (27%; P = 0.0166) and eight ADMN (24%; P = 0.0367), while with MY-PCR, mucosal HPVs were found in 11 PMs (22%; P = 0.04) and five ADMN (15%; P not significant). All control skin samples were negative for mucosal HPVs with both DNA amplification procedures. CONCLUSIONS: Using our PCR-ELISA methods, the detection of mucosal high-risk HPV genotypes in 24% of precursor lesions (ADMN) and in 27% of PMs adds to the body of evidence indicating a colocalization of mucosal HPV and tumoral melanocytic pathologies.


Subject(s)
Melanoma/virology , Nevus, Pigmented/virology , Papillomaviridae/isolation & purification , Precancerous Conditions/virology , Skin Neoplasms/virology , Adolescent , Adult , Aged , Aged, 80 and over , DNA, Viral/analysis , Enzyme-Linked Immunosorbent Assay/methods , Female , Genotype , Humans , Male , Melanoma/pathology , Middle Aged , Nevus, Pigmented/pathology , Papillomaviridae/classification , Papillomaviridae/genetics , Polymerase Chain Reaction/methods , Precancerous Conditions/pathology , Skin Neoplasms/pathology
10.
Epidemiol Infect ; 132(5): 857-62, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15473148

ABSTRACT

Serum samples from 446 Italian blood donors between 18 and 65 years of age were analysed for the presence of IgG against parvovirus B19 capsid proteins VP1 and VP2 including conformational and linear epitopes. The overall prevalence of IgG against parvovirus B19 capsid proteins VP1 and VP2 against at least one antigen type was 79.1 %. No significant difference was found between men and women. In the 18-27 years age group, 77.0 % of the population had experienced infection with the virus, reaching 88.5 % in the 48-57 years age group. The overall prevalence of IgG was 78.0 % against conformational VP1 + VP2 antigens, 74.9 % against conformational VP2, 70.9 % against linear VP1 and 23.3 % against linear VP2 in the analysis of the IgG response against different conformational and linear epitopes of VP1 and VP2. Although IgG against conformational VP1+VP2, conformational VP2 and linear VP1 was present in more than 60 % of subjects in all age groups, IgG against VP2 linear antigens was present in only 32% of subjects in the 18-27 years age group and then decreased to 20.5 % in the 28-37 years age group. A different trend was noted when IgG positivity against linear and conformational epitopes was analysed separately in men and women. A significant increase was found in seroprevalence of IgG against VP2 conformational antigens with increasing age in males and a significant decrease in seroprevalence of IgG against VP2 linear antigens in women with increasing age.


Subject(s)
Antigens, Viral/immunology , Blood Donors/statistics & numerical data , Capsid Proteins/immunology , Immunoglobulin G/immunology , Parvoviridae Infections/epidemiology , Parvovirus B19, Human/immunology , Parvovirus B19, Human/isolation & purification , Adolescent , Adult , Aged , Antibodies, Viral/analysis , Female , Humans , Italy/epidemiology , Male , Middle Aged , Parvoviridae Infections/blood , Parvoviridae Infections/etiology , Parvoviridae Infections/immunology , Seroepidemiologic Studies
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