Since March 2020, Spain (along with many other countries) has been severely affected by the ongoing coronavirus disease 19 (COVID‐19) pandemic caused by the rapid spread of a new virus (severe acute ...respiratory syndrome coronavirus 2; SARS‐CoV‐2). As part of global efforts to improve disease surveillance, we investigated how readily SARS‐CoV‐2 RNA could be detected in environmental samples collected from an isolated rural community in Spain with a high COVID‐19 prevalence (6% of the population of 883 inhabitants). The first diagnosis of COVID‐19‐compatible symptoms in the village was recorded on 3 March 2020, and the last known active case resolved on 5 June 2020. By 15 May, two months after strict movement constraints were imposed (‘lockdown’), and the cumulative number of symptomatic cases had increased to 53. Of those cases, 22 (41%) had been tested and confirmed by RT‐PCR. On 13 May and 5 June, samples were collected from high‐use surfaces and clothes in the homes of 13 confirmed cases, from surfaces in nine public service sites (e.g. supermarket and petrol station) and from the wastewater of the village sewage system. SARS‐CoV‐2 RNA was detected in 7 of 57 (12%) samples, including three households and three public sites. While there is not yet sufficient evidence to recommend environmental surveillance as a standard approach for COVID‐19 epidemiology, environmental surveillance research may contribute to advance knowledge about COVID‐19 by further elucidating virus shedding dynamics and environmental contamination, including the potential identification of animal reservoirs.
Lafora disease (LD), a fatal neurodegenerative disorder characterized by the presence of intracellular inclusions called Lafora bodies (LBs), is caused by loss-of-function mutations in laforin or ...malin. Previous studies suggested a role of these proteins in the regulation of glycogen biosynthesis, in glycogen dephosphorylation and in the modulation of the intracellular proteolytic systems. However, the contribution of each of these processes to LD pathogenesis is unclear. We have generated a malin-deficient (Epm2b−/−) mouse with a phenotype similar to that of LD patients. By 3-6 months of age, Epm2b−/− mice present neurological and behavioral abnormalities that correlate with a massive presence of LBs in the cortex, hippocampus and cerebellum. Sixteen-day-old Epm2b−/− mice, without detectable LBs, show an impairment of macroautophagy (hereafter called autophagy), which remains compromised in adult animals. These data demonstrate similarities between the Epm2a−/− and Epm2b−/− mice that provide further insights into LD pathogenesis. They illustrate that the dysfunction of autophagy is a consequence of the lack of laforin-malin complexes and a common feature of both mouse models of LD. Because this dysfunction precedes other pathological manifestations, we propose that decreased autophagy plays a primary role in the formation of LBs and it is critical in LD pathogenesis.
The probability integral transform of a continuous random variable
with distribution function
is a uniformly distributed random variable
. We define the angular probability integral transform (APIT) ...as
, which corresponds to a uniformly distributed angle on the unit circle. For circular (angular) random variables, the sum modulus 2
of absolutely continuous independent circular uniform random variables is a circular uniform random variable, that is, the circular uniform distribution is closed under summation modulus 2
, and it is a stable continuous distribution on the unit circle. If we consider the sum (difference) of the APITs of two random variables,
and
, and test for the circular uniformity of their sum (difference) modulus 2
, this is equivalent to test of independence of the original variables. In this study, we used a flexible family of nonnegative trigonometric sums (NNTS) circular distributions, which include the uniform circular distribution as a member of the family, to evaluate the power of the proposed independence test by generating samples from NNTS alternative distributions that could be at a closer proximity with respect to the circular uniform null distribution.
An outbreak of human leishmaniasis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in ...this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections.
The exploration of clinically relevant information in the free text of electronic health records (EHRs) holds the potential to positively impact clinical practice as well as knowledge regarding Crohn ...disease (CD), an inflammatory bowel disease that may affect any segment of the gastrointestinal tract. The EHRead technology, a clinical natural language processing (cNLP) system, was designed to detect and extract clinical information from narratives in the clinical notes contained in EHRs.
The aim of this study is to validate the performance of the EHRead technology in identifying information of patients with CD.
We used the EHRead technology to explore and extract CD-related clinical information from EHRs. To validate this tool, we compared the output of the EHRead technology with a manually curated gold standard to assess the quality of our cNLP system in detecting records containing any reference to CD and its related variables.
The validation metrics for the main variable (CD) were a precision of 0.88, a recall of 0.98, and an F1 score of 0.93. Regarding the secondary variables, we obtained a precision of 0.91, a recall of 0.71, and an F1 score of 0.80 for CD flare, while for the variable vedolizumab (treatment), a precision, recall, and F1 score of 0.86, 0.94, and 0.90 were obtained, respectively.
This evaluation demonstrates the ability of the EHRead technology to identify patients with CD and their related variables from the free text of EHRs. To the best of our knowledge, this study is the first to use a cNLP system for the identification of CD in EHRs written in Spanish.
The P22 ELISA was recently developed for the serodiagnosis of animal tuberculosis. Herein, the stability of the P22 antigen in different presentations and storage conditions, and the cross-reactivity ...with Corynebacterium pseudotuberculosis infection in small ruminants were evaluated. For the stability assay, serum samples from cows, sheep, goats, alpacas, badgers, and wild boar were used in the P22 ELISA. The cross-reactivity analysis used sera from sheep and goats with caseous lymphadenitis (CLA). Differences in the immune recognition of P22 were found when the antigen was stored at 40 °C, but without altering the negative or positive status of each sample. P22 ELISA presented 5.71 % cross-reactivity when CLA-positive sheep were evaluated, but no cross-reaction was observed among CLA-positive goat serum samples. This study showed that the P22 protein complex is stable under different formulations and temperatures, and that the assay presents a low cross-reactivity with CLA.
•P22 ELISA is a very stable diagnostic tool for tuberculosis diagnosis.•P22 protein complex is more stable when maintained in solution at 4 °C.•Freeze-drying is a reliable tool for P22 storage.•P22 ELISA did not present cross-reactions for CLA-positive goats.•P22 ELISA presented a 5.7 % cross-reactivity for CLA-positive sheep.
•This qPCR resulted to be more sensitive than nested PCR and the percentage of positive animals detected by qPCR in at least two out of three samples tested was higher than those detected by IFAT and ...isolation.•This qPCR is a suitable method for detecting L. infantum antigen in Leporidae and presumably to be extended to other wild animals.•This qPCR employed on hair samples could also be used for the surveillance of leishmaniosis in wild animals and results as a new method for L. infantum detection with high sensitivity and specificity.
The aim of this study was to compare a quantitative real-time PCR (qPCR) validated for the detection of Leishmania infantum in dogs with a nested PCR but in wild Leporidae. Additionally, L. infantum results from indirect immunofluorescent antibody test (IFAT) and in vitro culture were also compared with qPCR. Different samples (spleen, skin and hair) recovered from 224 European rabbits and 70 Iberian hares from two green areas of Madrid Council were analysed for the detection of L. infantum. The presence of Leishmania kDNA was detected by qPCR in 58 out of 221 (26.24%), 162 out of 203 (79.8%) and 22 out of 33 (66.67%) analysed rabbits on spleen, skin and hair samples, respectively; and in 7 out of 69 (10.14%), 39 out of 70 (55.71%) and 17 out of 32 (53.13%) test hares on spleen, skin and hair samples, respectively. The qPCR in all test samples resulted to be more sensitive than nested PCR, with a limit of detection of 1.43 fg/reaction (0.039 parasites) for L. infantum genomic DNA. Additionally, the percentage of positive animals detected by qPCR in at least two out of three samples (n=221 rabbits and 70 hares) tested was higher than those detected by IFAT (n=190 rabbits and 61 hares) and isolation (n=75 rabbits and 20 hares). The highest level of agreement was obtained by nested PCR on spleen/skin (89%/83%) samples and qPCR on spleen samples (81%), followed by IFAT (48%) and qPCR on skin (32%) samples. Our results demonstrate this qPCR is a suitable method for detecting L. infantum DNA in different samples suggesting hair could be considered an adequate sample for direct, reliable and non-invasive diagnosis of L. infantum in wild animals.
parasites cause outstanding levels of morbidity and mortality in many developing countries in tropical and subtropical regions. Numerous gene expression profiling studies have been performed ...comparing different
species' life-cycles and stage forms in regard to their distinct infective ability. Based on expression patterns, homology to human orthologues, in silico HLA-binding predictions, and annotated functions, we were able to select several vaccine candidates which are currently under study. One of these candidates is the
ubiquitin-conjugating enzyme E2 (LiUBC1), whose relative levels, subcellular location, in vitro infectivity in the U937 myeloid human cell model, and protection levels in Syrian hamsters against
infection were studied herein. LiUBC1 displays a low level of similarity with the mammalian orthologs and relevant structure differences, such as the C-terminal domain, which is absent in the human ortholog. LiUBC1 is present in highly infective promastigotes. Knock-in parasites overexpressing the enzyme increased their infectivity, according to in vitro experiments. Syrian hamsters immunized with the recombinant LiUBC1 protein did not show any parasite burden in the spleen, unlike the infection control group. The IFN-γ transcript levels in splenocytes were significantly higher in the LiUBC1 immunized group. Therefore, LiUBC1 induced partial protection against
in the Syrian hamster model.
Background
Cutaneous forms of leishmaniosis due to Leishmania braziliensis have been reported in horses in the New World. Domestic animals play a role in the transmission of the disease. In Costa ...Rica, human cases of L. braziliensis, L. panamensis and L. infantum have been reported.
Objectives
The present report describes five cases of equine cutaneous leishmaniosis in Costa Rica. The aetiological diagnosis was based on the presence of the parasite within the lesions.
Methods
Skin biopsies were used to perform histopathological analyses of the lesions. Immunohistochemistry was used to detect the presence of the Leishmania spp. antigens in tissue sections. Laser‐capture micro‐dissection and quantitative real‐time PCR techniques were carried out to detect the pathogen nucleic acid within the microscopic lesions.
Results
Histopathological analyses showed a granulomatous inflammation within the dermis, with multi‐nucleated giant cells, macrophages, lymphocytes and few neutrophils and eosinophils. We detected the parasite by immunohistochemistry, using a rabbit polyclonal antibody raised against Leishmania spp. However, we could not identify Leishmania spp. by quantitative real‐time PCR in formalin‐fixed paraffin‐embedded tissues, using specific primers for the conserved region in the minicircle of the Leishmania DNA kinetoplast.
Conclusions
Our results emphasise the importance of Leishmania spp. not only as a causative agent of equine cutaneous disease in the New World, but also as a possible emerging pathogen. Leishmaniosis is one of the most prevalent parasitic public health problems worldwide, and equines may have a role in the epidemiology of the disease.
The present report describes 5 cases of equine cutaneous leishmaniosis in Costa Rica using histopathology, immunohistochemistry and qPCR. Our results emphasise the importance of Leishmania spp. not only as a causative agent of equine cutaneous disease in the New World but also as a possible emerging pathogen. Leishmaniosis is one of the most prevalent parasitic public health problems worldwide, and equines may have a role in the epidemiology of the disease.
•Paratuberculosis vaccination interferes with the diagnosis of tuberculosis.•The interference on the cellular-based diagnostic tests decreases over time.•Consecutive intradermal tests in ...paratuberculosis vaccinated animals increases the interference on antibody-based diagnostic tests.•Results are useful for the design of tuberculosis eradication programs.
Vaccination against paratuberculosis (PTB) in goats is a cost-effective control strategy, and is also effective as regards preventing the onset of clinical cases. However, it causes interference in the diagnostic tests used in the control of tuberculosis (TB). A group of 99 goats from a herd with no history of TB or PTB infection was vaccinated against PTB at seven months of age. They then underwent consecutive intradermal tests single (SIT) and comparative (CIT) intradermal tuberculin tests), interferon-gamma release assays (IGRA) and two serological tests (p22_CE and DR-ELISA) every three months, until the interference disappeared. When using the SIT test, a variable number of positive reactors were observed at 3 months (T3; 32.3%, 95% CI 23.9–42.1), 6 months (T6; 11.5%, 95% CI 6.5–19.4), 9 months (T9; 6.4%, 95% CI 3.0–13.2) and 12 months (T12; 0%, 95% CI 0–4.0) post-vaccination. In contrast, the CIT test had a specificity (Sp) of 100% (95%, CI 96.0–100, regardless of the time post-vaccination. The IGRA also obtained high Sp values throughout the study period. No significant interference in the serological tests was recorded at T3 p22_CE, Sp = 96% (95% CI 90.1–98.4) and DR-ELISA, Sp = 98% (95% CI 92.9–99.4), although an increase in antibody titers was observed in the following herd testing events. In conclusion, the use of the SIT test causes the onset of false-positive reactors if applied before 12 months post-vaccination in a TB-free/PTB-vaccinated herd. Nevertheless, the CIT test and IGRA obtained high Sp values under these epidemiological circumstances. The serological tests were also highly specific in the case of PTB-vaccinated goats, although their Sp decreased significantly after several intradermal tests.
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