Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
24
result(s) for
"Altet, Laura"
Sort by:
Triple lines gold nanoparticle-based lateral flow assay for enhanced and simultaneous detection of Leishmania DNA and endogenous control
by
Lourdes Rivas Alfredo de la Escosura-Muniz Lorena Serrano Laura Altet Olga Francino ArmandSanchez Arben Merkoci
in
Amplification
,
Antibodies
,
Assaying
2015
A novel triple lines lateral-flow assay (LFA) with enhanced sensitivity for the detection of Leishmania infantum DNA in dog blood samples was designed and successfully applied. The enhanced LFA methodology takes advantage of the gold nanoparticle tags (AuNPs) conjugated to polyclonal secondary antibodies, which recognize anti-FITC antibodies. The polyclonal nature of the secondary antibodies allows for multiple binding to primary antibodies, leading to enhanced AuNP plasmonics signal. Furthermore, endogenous control consisting of the amplified dog 18S rRNA gene was introduced to avoid false negatives. Using this strategy, 0.038 spiked Leishmania parasites per DNA amplification reaction (1 parasite/100 μL of DNA sample) were detected. Detection limit of LFA was found to be lower than that of the conventional techniques. In summary, our novel LFA design is a universal and simple sensing altemative that can be extended to several other biosensing scenarios.
Journal Article
Detection of vector-borne pathogens in owned dogs with cranial cruciate ligament rupture living in the Mediterranean area
by
Naranjo, Carolina
,
Altet, Laura
,
Tabar, María-Dolores
in
16th Symposium on Companion Vector-Borne Diseases (CVBD)
,
Anaplasma
,
Anaplasma - genetics
2022
Background
Cranial cruciate ligament rupture (CCLR) results from a multifactorial degenerative process that leads to rupture of the ligament. Vector-borne pathogens (VBP) in dogs can induce joint disease but their role in CCLR has not been previously investigated. The aim of the present work is to evaluate the prevalence of VBP in dogs with CCLR.
Methods
This was a prospective study that included 46 dogs presented for CCLR surgical treatment and 16 control dogs euthanized for diseases unrelated to the joints. Specimens collected included blood, synovial fluid, and synovial membrane biopsy. Pathogen testing consisted of serology for
Leishmania infantum
(quantitative ELISA),
Ehrlichia canis/ewingii
,
Borrelia burgdorferi
,
Anaplasma phagocytophilum
/
platys
, and
Dirofilaria immitis
(4DX IDEXX test), and PCR for
L. infantum
,
Ehrlichia
/
Anaplasma
spp.,
Bartonella
spp., piroplasms (
Babesia
spp. and
Theileria
spp.), and filariae (
D. immitis
,
Dirofilaria repens
,
Acanthocheilonema dracunculoides
,
Acanthocheilonema reconditum,
and
Cercopithifilaria
spp.) on both EDTA-whole blood (EB) and synovial fluid (SF) samples. SF cytology and histopathological evaluation of synovial membrane were also performed.
Results
The prevalence of VBP was 19.6% in the CCLR group and 18.8% in the control group, with no statistical difference among them. The presence of synovitis was not more frequent in CCLR dogs (45.6%) than in control dogs (43.7%). Lymphoplasmacytic infiltration was the most common inflammatory pattern detected in the joints of both groups of dogs.
Conclusions
This study failed to demonstrate a role of canine VBP in CCLR or the presence or different pattern of joint inflammation in pathogen-positive dogs.
Graphical Abstract
Journal Article
Ticks and associated pathogens collected from cats in Sicily and Calabria (Italy)
2015
Background
Limited information is available about the species of ticks infesting the cat and the pathogens that they harbor. The aims of the present study were to identify the species of ticks removed from cats living in Sicily and Calabria (Italy) and to detect DNA of vector-borne pathogens in the same ticks.
Findings
Morphological identification of 132 adult ticks collected throughout the year from cats was carried out. Real-time PCRs for
Hepatozoon felis
, Piroplasmid,
Ehrlichia/Anaplasma
spp.,
Rickettsia
spp.,
Bartonella
spp.,
Mycoplasma
spp. and
Leishmania infantum
were performed from each individual tick.
Ticks belonging to
Rhipicephalus
(
R. sanguineus
sensu lato,
R. pusillus
) and
Ixodes
(
I. ricinus
,
I. ventalloi
) genera were identified.
Ixodes ventalloi
was the most frequently found tick species (47 %).
The positivity rate to at least one pathogen was 14.4 % (19/132 ticks).
Leishmania infantum
,
Rickettsia
spp. (
R. monacensis
and
R. helvetica
),
Bartonella
spp. (
B. clarridgeiae
), Piroplasmid (
Babesia vogeli
), and
Ehrlichia/Anaplasma
spp. (
E. canis
) DNAs were amplified in 8.3, 5.3, 1.5, 0.75 and 0.75 % of ticks, respectively.
Hepatozoon felis
,
Anaplasma
spp. and hemotropic
Mycoplasma
spp. DNAs were not detected. Four (21.1 %) out of nineteen positive ticks were co-infected.
Conclusions
This study provides novel data about ticks infesting cats and the DNA of pathogens that they harbor. In Southern Italy, anti-tick prophylaxis should be implemented throughout the year in cats without neglecting winter time.
Journal Article
First description of Bartonella koehlerae infection in a Spanish dog with infective endocarditis
by
Maggi, Ricardo G.
,
Altet, Laura
,
Altimira, Jaume
in
12th Symposium on Companion Vector-borne Diseases (CVBD)
,
Abdomen
,
Animals
2017
Background
Bartonella koehlerae
has been recently described as a new cat- and cat fleas-associated agent of culture-negative human endocarditis. It has been also encountered in one dog from Israel and six dogs from the USA, but other clinically relevant reports involving this bacterium are lacking.
Results
A 7-year-old intact male mixed dog presented with clinico-pathological signs consistent with mitral endocarditis and cutaneous hemangiosarcoma. Molecular studies revealed the presence of
Bartonella koehlerae
DNA in samples from blood and mitral valve tissue.
Conclusions
This is the first description of
B. koehlerae
in Spain, corroborating that it can also be detected in dogs.
Bartonella koehlerae
infection should also be considered in Spain in humans and dogs presenting with clinical disease suggestive of it, such as culture-negative endocarditis.
Journal Article
Canine leishmaniasis: the key points for qPCR result interpretation
by
Sanchez, Armand
,
Quilez, Javier
,
Altet, Laura
in
6th Symposium on Canine Vector-Borne Diseases
,
Animals
,
Biomedical and Life Sciences
2011
BACKGROUND: Diagnosis and follow up of CanL is difficult since the range of clinical signs is varied and seroprevalence is high in endemic areas. The aims of this study were: i) demonstrate the advantages of Leishmania qPCR to diagnose and control CanL and highlight its prognostic value and ii) propose guidelines for tissue selection and infection monitoring. FINDINGS: This study included 710 dogs living in an endemic area of leishmaniasis. Forty percent (285/710) exhibited clinical signs consistent with CanL. Infection was detected in 36.3% (258/710) of the dogs of which 4.5% (32/710) were detected by qPCR, 16.2% (115/710) detected by ELISA and 15.6% (111/710) tested positive for both tests. Only 17.9% (127/710) of the dogs were classified sick (affected) with CanL. All symptomatic dogs with medium or high ELISA titers were qPCR-positive in blood samples. All dogs with inconclusive or low ELISA results with high or medium qPCR parasitemia values developed the disease. Seventy one percent of asymptomatic ELISA-positive dogs confirmed by qPCR (medium to high parasitemia) developed the disease. Bone marrow or lymph node aspirate should be selected to ensure the absence of the parasite in asymptomatic dogs: 100-1,000 parasites/ml in bone marrow are detectable in blood, whereas lower parasite loads are usually negative. Almost 10% of negative samples in blood were positive in conjunctival swabs. CONCLUSIONS: Because qPCR allows parasite quantification, it is an effective tool to confirm a diagnosis of CanL in (i) cases of inconclusive ELISA results, (ii) when the dog has not yet seroconverted, or (iii) for treatment monitoring.
Journal Article
Infection and exposure to vector-borne pathogens in rural dogs and their ticks, Uganda
by
Fernández de Mera, Isabel G.
,
Chirife, Andrea D.
,
Mugisha, Lawrence
in
Analysis
,
Anaplasma - genetics
,
Anaplasma - isolation & purification
2015
Background
In rural parts of Africa, dogs live in close association with humans and livestock, roam freely, and usually do not receive prophylactic measures. Thus, they are a source of infectious disease for humans and for wildlife such as protected carnivores. In 2011, an epidemiological study was carried out around three conservation areas in Uganda to detect the presence and determine the prevalence of vector-borne pathogens in rural dogs and associated ticks to evaluate the risk that these pathogens pose to humans and wildlife.
Methods
Serum samples (
n
= 105), blood smears (
n
= 43) and blood preserved on FTA cards (
n
= 38) and ticks (58 monospecific pools of
Haemaphysalis leachi
and
Rhipicephalus praetextatus
including 312 ticks from 52 dogs) were collected from dogs. Dog sera were tested by indirect immunofluorescence to detect the presence of antibodies against
Rickettsia conorii
and
Ehrlichia canis
. Antibodies against
R. conorii
were also examined by indirect enzyme immunoassay. Real time PCR for the detection of
Rickettsia
spp., Anaplasmataceae,
Bartonella
spp. and
Babesia
spp. was performed in DNA extracted from FTA cards and ticks.
Results
99 % of the dogs were seropositive to
Rickettsia
spp. and 29.5 % to
Ehrlichia
spp. Molecular analyses revealed that 7.8 % of the blood samples were infected with
Babesia rossi
, and all were negative for
Rickettsia
spp. and
Ehrlichia
spp. Ticks were infected with
Rickettsia
sp. (18.9 %), including
R. conorii
and
R. massiliae
;
Ehrlichia
sp. (18.9 %), including
E. chaffeensis
and
Anaplasma platys
; and
B. rossi
(1.7 %).
Bartonella
spp. was not detected in any of the blood or tick samples.
Conclusions
This study confirms the presence of previously undetected vector-borne pathogens of humans and animals in East Africa. We recommend that dog owners in rural Uganda be advised to protect their animals against ectoparasites to prevent the transmission of pathogens to humans and wildlife.
Journal Article
A selective sweep of >8 Mb on chromosome 26 in the Boxer genome
by
Short, Andrea D
,
Sanchez, Armand
,
Francino, Olga
in
Animal Genetics and Genomics
,
Animals
,
Biomedical and Life Sciences
2011
Background
Modern dog breeds display traits that are either breed-specific or shared by a few breeds as a result of genetic bottlenecks during the breed creation process and artificial selection for breed standards. Selective sweeps in the genome result from strong selection and can be detected as a reduction or elimination of polymorphism in a given region of the genome.
Results
Extended regions of homozygosity, indicative of selective sweeps, were identified in a genome-wide scan dataset of 25 Boxers from the United Kingdom genotyped at ~20,000 single-nucleotide polymorphisms (SNPs). These regions were further examined in a second dataset of Boxers collected from a different geographical location and genotyped using higher density SNP arrays (~170,000 SNPs). A selective sweep previously associated with canine brachycephaly was detected on chromosome 1. A novel selective sweep of over 8 Mb was observed on chromosome 26 in Boxer and for a shorter region in English and French bulldogs. It was absent in 171 samples from eight other dog breeds and 7 Iberian wolf samples. A region of extended increased heterozygosity on chromosome 9 overlapped with a previously reported copy number variant (CNV) which was polymorphic in multiple dog breeds.
Conclusion
A selective sweep of more than 8 Mb on chromosome 26 was identified in the Boxer genome. This sweep is likely caused by strong artificial selection for a trait of interest and could have inadvertently led to undesired health implications for this breed. Furthermore, we provide supporting evidence for two previously described regions: a selective sweep on chromosome 1 associated with canine brachycephaly and a CNV on chromosome 9 polymorphic in multiple dog breeds.
Journal Article
Genetic Control of Canine Leishmaniasis: Genome-Wide Association Study and Genomic Selection Analysis
2012
The current disease model for leishmaniasis suggests that only a proportion of infected individuals develop clinical disease, while others are asymptomatically infected due to immune control of infection. The factors that determine whether individuals progress to clinical disease following Leishmania infection are unclear, although previous studies suggest a role for host genetics. Our hypothesis was that canine leishmaniasis is a complex disease with multiple loci responsible for the progression of the disease from Leishmania infection.
Genome-wide association and genomic selection approaches were applied to a population-based case-control dataset of 219 dogs from a single breed (Boxer) genotyped for ~170,000 SNPs. Firstly, we aimed to identify individual disease loci; secondly, we quantified the genetic component of the observed phenotypic variance; and thirdly, we tested whether genome-wide SNP data could accurately predict the disease.
We estimated that a substantial proportion of the genome is affecting the trait and that its heritability could be as high as 60%. Using the genome-wide association approach, the strongest associations were on chromosomes 1, 4 and 20, although none of these were statistically significant at a genome-wide level and after correcting for genetic stratification and lifestyle. Amongst these associations, chromosome 4: 61.2-76.9 Mb maps to a locus that has previously been associated with host susceptibility to human and murine leishmaniasis, and genomic selection estimated markers in this region to have the greatest effect on the phenotype. We therefore propose these regions as candidates for replication studies. An important finding of this study was the significant predictive value from using the genomic information. We found that the phenotype could be predicted with an accuracy of ~0.29 in new samples and that the affection status was correctly predicted in 60% of dogs, significantly higher than expected by chance, and with satisfactory sensitivity-specificity values (AUC = 0.63).
Journal Article
Early reduction of Leishmania infantum-specific antibodies and blood parasitemia during treatment in dogs with moderate or severe disease
by
Montserrat, Sara
,
Di Filippo, Laura
,
Ordeix, Laura
in
11th Symposium on Canine Vector-Borne Diseases
,
allopurinol
,
Animals
2016
Background
Leishmania infantum
-specific antibodies are used extensively for the diagnosis and monitoring of treatment in canine leishmaniosis. Different views have been described for the measurement of
L. infantum
antibody levels for the monitoring of anti-leishmanial treatment. In addition, molecular techniques using blood are frequently employed in the clinical setting. However, there are not enough studies to prove the usefulness of PCR in diagnosis, treatment monitoring and in assessing the prognosis of the disease. The objectives of this study were to evaluate
L. infantum
-specific antibodies and blood parasitemia at the time of diagnosis and during treatment and to correlate these with the dog’s clinical status.
Methods
Thirty-seven dogs were diagnosed and followed-up during treatment (days 30, 180 and 365). The treatment protocol consisted of a combination of meglumine antimoniate for one month and allopurinol for at least one year.
Leishmania infantum
-specific antibodies and blood parasitemia were assessed by an end point sera dilution ELISA and by real-time PCR, respectively.
Results
The majority of dogs were classified as LeishVet stage II (moderate disease) at the time of diagnosis (86 %) and the rest as stage III. Results showed variable levels of specific antibodies at the time of diagnosis [median ± interquartile range (IQR): 1372 ± 8803 ELISA units (EU)]. Twenty-three seropositive dogs (64 %) were detected as PCR-positive at the time of diagnosis. Interestingly, a rapid significant antibody level reduction was observed by day 30 of treatment (median ± IQR: 604 ± 2168 EU). A continuing significant decrease of specific antibodies was also found at days 180 (median ± IQR: 201 ± 676 EU) and 365 (median ± IQR: 133 ± 329 EU) in association with clinical improvement. A significant blood parasitemia reduction was also observed at all time points studied. Mean parasites/ml ± SD were 19.4 ± 79.1 on day 0, 2.2 ± 11.7 on day 30, 0.9 ± 2.9 on day 180, and 0.3 ± 0.7 on day 365.
Conclusions
This study reports a significant reduction of
L. infantum
antibodies measured by an end point sera dilution ELISA method after 30 days of treatment associated with clinical improvement. A low proportion of sick dogs with moderate disease were negative by blood real-time PCR at the time of diagnosis.
Journal Article