Serological study of feline leishmaniasis and molecular detection of Leishmania infantum and Leishmania braziliensis in cats (Felis catus)

Abstract Blood samples and swabs from ocular conjunctiva and mouth were obtained from 64 cats. Of 64 serum samples, 19 were positive for Leishmania antibodies by ELISA (29.80%). Eight cats were positive by PCR (12.5%) in swab samples from mouth and/or ocular mucosa. Poor kappa agreement between serological and molecular results (k = 0.16) was obtained. From five positive PCR samples one was L. braziliensis and four were L. infantum. Phylogenetic analysis performed with the five isolates of Leishmania, showed that samples of L. infantum isolated from the cats were phylogenetically close to those isolated from domestic dogs in Brazil, while the L. braziliensis is very similar to the one described in humans in Venezuela. The study demonstrated that, despite high seropositivity for Leishmania in cats living in the study region, poor agreement between serological and molecular results indicate that positive serology is not indicative of Leishmania infection in cats. Parasite DNA can be detected in ocular conjunctiva and oral swabs from cats, indicating that such samples could be used for diagnosis. Results of phylogenetic analyzes show that L. infantum circulating in Brazil is capable of infecting different hosts, demonstrating the parasite's ability to overcome the interspecies barrier.

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Role of Circulating Immune Complexes in the Pathogenesis of Canine Leishmaniasis: New Players in Vaccine Development

Microorganisms ◽

10.3390/microorganisms9040712 ◽

2021 ◽

Vol 9 (4) ◽

pp. 712

Author(s):

Cristina Cacheiro-Llaguno ◽

Nuria Parody ◽

Marta R. Escutia ◽

Jerónimo Carnés

Keyword(s):

Immune Complexes ◽

Vaccine Development ◽

Correct Diagnosis ◽

Circulating Immune Complexes ◽

Response To Treatment ◽

Canine Leishmaniasis ◽

Leishmania Infection ◽

Serum Samples ◽

Humoral Immune

During canine visceral leishmaniasis (CanL), due to Leishmania infantum (L. infantum), uncontrolled infection leads to a strong humoral immune response. As a consequence of the production of high antibody levels and the prolonged presence of parasite antigens, circulating immune complexes (CIC) are formed, which can be deposited in certain organs and tissues, inducing vasculitis, uveitis, dermatitis and especially glomerulonephritis and renal failure. A method to detect CIC and quantify their levels in serum samples from dogs infected with L. infantum has been recently described. It allowed demonstration of a correlation between CIC levels and disease severity. Thus, CIC measurement may be useful for diagnosis, assessment of disease progression and monitoring response to treatment. This is an interesting finding, considering that there remains an urgent need for identification of novel biomarkers to achieve a correct diagnosis and for optimal disease staging of dogs suffering from Leishmania infection. The objective of the present review is to shed light on the role of CIC in CanL, as well as to highlight their potential use not only as diagnostic and prognostic biomarkers but also as a valuable tool in vaccine development and new immunotherapy strategies to prevent or control disease outcome.

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Leishmania infection in bats from a non-endemic region of Leishmaniasis in Brazil

Parasitology ◽

10.1017/s0031182017001500 ◽

2017 ◽

Vol 144 (14) ◽

pp. 1980-1986 ◽

Cited By ~ 6

Author(s):

CÉSAR GÓMEZ-HERNÁNDEZ ◽

ELAINE C. BENTO ◽

KARINE REZENDE-OLIVEIRA ◽

GABRIEL A. N. NASCENTES ◽

CECILIA G. BARBOSA ◽

...

Keyword(s):

Urban Areas ◽

Leishmania Infection ◽

Leishmania Braziliensis ◽

Endemic Region ◽

Blood Samples ◽

Rural And Urban Areas ◽

Rural And Urban ◽

Minas Gerais State ◽

Close Relationship ◽

Epidemiological Significance

SUMMARYLeishmaniasis is a complex of zoonotic diseases caused by parasites of the genus Leishmania, which can develop in domestic as well as wild animals and humans throughout the world. Currently, this disease is spreading in rural and urban areas of non-endemic regions in Brazil. Recently, bats have gained epidemiological significance in leishmaniasis due to its close relationship with human settlements. In this study, we investigated the presence of Leishmania spp. DNA in blood samples from 448 bats belonging to four families representing 20 species that were captured in the Triangulo Mineiro and Alto Paranaiba areas of Minas Gerais State (non-endemic areas for leishmaniasis), Brazil. Leishmania spp. DNA was detected in 8·0% of the blood samples, 41·6% of which were Leishmania infantum, 38·9% Leishmania amazonensis and 19·4% Leishmania braziliensis. No positive correlation was found between Leishmania spp. and bat food source. The species with more infection rates were the insectivorous bats Eumops perotis; 22·2% (4/18) of which tested positive for Leishmania DNA. The presence of Leishmania in the bat blood samples, as observed in this study, represents epidemiological importance due to the absence of Leishmaniasis cases in the region.

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Molecular detection and clinical aspects of porcine circovirus 3 infection in pigs from Brazil

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-4162-11924 ◽

2020 ◽

Vol 72 (5) ◽

pp. 1731-1736

Author(s):

A.C.M. Cruz ◽

I.L.F. Rodrigues ◽

A.E. Souza ◽

F.B. Knackfuss ◽

R.L. Silveira ◽

...

Keyword(s):

Molecular Detection ◽

Porcine Circovirus ◽

Southeastern Brazil ◽

Clinical Aspects ◽

Statistical Association ◽

Serum Samples ◽

Clinical Presentations ◽

Porcine Circovirus 3 ◽

Clinical Conditions ◽

Swine Serum

ABSTRACT Porcine circovirus 3 (PCV-3) DNA has been detected in serum samples from apparently healthy pigs as well as pigs with different clinical conditions. Molecular detection of PCV-3 was observed in swine serum samples from Southeastern - Brazil using a nested PCR designed specifically for this study. The epidemiology and clinical aspects of PCV-3 infection were evaluated. The samples originated from 154 pigs of both genders from different production phases and with different clinical presentations, sampled from 31 pig farms visited between 2013 and 2018. In this study, PCV-3 was detected in 26.7% of samples from all populations across varying ages. Statistical association (P=0.0285) was observed only between animals with respiratory signs and PCV-3; no PCV-3-positive animal had diarrhea. No statistical association was observed between PCV-3 and age, or gender of the pigs. Because PCV-3 is a newly discovered virus, there is very little information about its epidemiology. We hope that these data can help in future studies investigating PCV-3 epidemiology.

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Presence of antibodies against Toxoplasma gondii, Neospora caninum and Leishmania infantum in dogs from Piauí

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612011000200004 ◽

2011 ◽

Vol 20 (2) ◽

pp. 111-114 ◽

Cited By ~ 15

Author(s):

Marcos Gomes Lopes ◽

Ivete Lopes Mendonça ◽

Kleber Portela Fortes ◽

Marcos Amaku ◽

Hilda de Fátima Jesus Pena ◽

...

Keyword(s):

Toxoplasma Gondii ◽

Leishmania Infantum ◽

Neospora Caninum ◽

Fluorescent Antibody ◽

Northeastern Brazil ◽

Leishmania Infection ◽

Serum Samples ◽

Chi Square ◽

Leishmania Spp ◽

And Gender

This study aimed to evaluate the presence of antibodies against Neospora caninum, Toxoplasma gondii and Leishmania infantum in dogs attended at the Veterinary Hospital of the Federal University of Piauí, Northeastern Brazil, where there are no reports of the occurrence of N. caninum and T. gondii in dogs. Serum samples from 530 dogs of genders, different ages and breeds from the municipality of Teresina and nearby towns were analyzed using three indirect fluorescent antibody tests, each one targeting one of the three agents. The associations between the parasites and gender, breed and age of the dogs were assessed by the chi-square test (p > 0.05). The occurrence of antibodies to N. caninum, T. gondii and L. infantum was 3.2, 18.0 and 78.1%, respectively. Toxoplasma gondii was more frequently found in older dogs (p < 0.05) whereas L. infantum was more common in animals aged between 1 to 3 years (p < 0.05). In order to evaluate potential associations between the presence of anti-N. caninum and anti-T. gondii antibodies and Leishmania infection, 240 dogs were selected (120 positive and 120 negative for Leishmania spp.), based on serological and parasitological diagnoses. No association was found between Leishmania spp. and the coccidian parasites (p > 0.05). The results confirm the exposure of dogs to these parasites in the State of Piauí.

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Molecular Detection of Human Herpes Viruses in Suspected Measles Serum Samples from Senegal, 2014 to 2017

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.20-1444 ◽

2021 ◽

Author(s):

Mamadou Malado Jallow ◽

Amary Fall ◽

Serigne Fallou Wade ◽

Ndeye Sophie Fall ◽

Davy Kiori ◽

...

Keyword(s):

Molecular Detection ◽

Seasonal Pattern ◽

Clinical Specimen ◽

Human Herpesvirus ◽

Case Definition ◽

Herpes Viruses ◽

Human Herpes ◽

Serum Samples ◽

Cutaneous Lesions ◽

Human Herpes Viruses

Herpesviruses are known to cause a diversity of clinical syndromes, ranging from minor cutaneous lesions to life-threatening illnesses, especially in immunocompromised hosts. Here, we investigate retrospectively the contribution of five human herpesviruses, including herpes simplex virus Cytomegalovirus (CMV), the Epstein–Barr virus (EBV), human herpesvirus 6, and varicella zoster virus (VZV) in serum samples collected from measles suspected patients with at least fever and rash. Sera specimens were first tested for serological evidence of measles and rubella virus infection by ELISA, and DNA extracted from an aliquot of each clinical specimen for molecular detection of human herpes viruses by RT-qPCR. A total of 3,358 specimens have been collected and tested for herpes viruses. Nearly half of the overall suspected cases were children younger than 5 years (49.4%). Of the 3,358 sera tested by ELISA, 227 (6.7%) were measles laboratory confirmed and 152 (4.5%) rubella laboratory confirmed. Herpes viruses were detected in 1763 (52.5%), and VZV was the most common with 44.3%, followed by EBV with 10.7%. Coinfections were found in 352 (20%) cases, and the most common co-detections were VZV/EBV or VZV/CMV (169 and 81 cases, respectively). A clear seasonal pattern of VZV, EBV, and CMV identification was observed, with the highest incidence between February and April each year. Results of this investigation provide more insights into cutaneous rash syndrome etiologies in patients sampled in the framework of measles/rubella surveillance in Senegal, which is useful for the guidance of both case definition revision and clinical practice as well as for public health policy.

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Comparison Between Measured and Calculated Free Calcium Values at Different Serum Albumin Concentrations

Journal of Laboratory Physicians ◽

10.4103/0974-2727.180785 ◽

2016 ◽

Vol 8 (02) ◽

pp. 071-076 ◽

Cited By ~ 4

Author(s):

Altaf Ahmad Mir ◽

Bela Goyal ◽

Sudip Kumar Datta ◽

Saidaiah Ikkurthi ◽

Arnab Pal

Keyword(s):

Serum Albumin ◽

Tertiary Care ◽

Free Calcium ◽

Albumin Concentration ◽

Care Hospital ◽

Serum Samples ◽

Spectrophotometric Methods ◽

Significant Difference ◽

Clinical Biochemistry Laboratory ◽

The One

ABSTRACT Introduction: Free ionic calcium is the metabolically active component of total calcium (TCa) in blood. However, most laboratories report TCa levels that are dependent on serum albumin concentration. Hence, several formulae have evolved to calculate free calcium levels from TCa after adjustment for albumin. However, free calcium can directly be measured using direct ion selective electrodes rather than spectrophotometric methods used in autoanalyzers. Objectives: This study compares the levels of free calcium obtained by measurement by direct ion selective electrode (ISE) and the one calculated as a function of TCa by formulae. Materials and Methods: A total of 254 serum samples submitted to clinical biochemistry laboratory of a tertiary care hospital were analyzed for total protein, albumin, and TCa by standard spectrophotometric methods and for free calcium by direct ISE. Three commonly used formulae viz. Orrell, Berry et al. and Payne et al. were used to calculate adjusted TCa. Calculated free calcium was obtained by taking 50% of these values. Results: A significant difference (P < 0.05) was observed between calculated free calcium by all the three formulae and measured free calcium estimated by direct ISE using paired t-test and Bland–Altman plots. Conclusion: Formulae for predicting free calcium by estimating TCa and albumin lacks consistency in prediction and free calcium should be evaluated by direct measurement.

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Frequency of toxocara infection in children attended by the health public service of Maringá, south Brazil

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652007000600002 ◽

2007 ◽

Vol 49 (6) ◽

pp. 343-348 ◽

Cited By ~ 30

Author(s):

Márcia L. Paludo ◽

Dina L.M. Falavigna ◽

Guita R. Elefant ◽

Mônica L. Gomes ◽

Magda L.M. Baggio ◽

...

Keyword(s):

Public Service ◽

Signs And Symptoms ◽

Toxocara Canis ◽

Public Health Services ◽

Serum Samples ◽

Positive Serology ◽

Gastrointestinal Problems ◽

Prevention Activities ◽

Secretory Products ◽

South Brazil

The lack of specific laboratorial diagnosis methods and precise symptoms makes the toxocariasis a neglected disease in Public Health Services. This study aims to determine the frequency of Toxocara spp. infection in children attended by the Health Public Service of Hospital Municipal de Maringá, South Brazil. To evaluate the association of epidemiological and clinical data, an observational and cross-section study was carried out. From 14,690 attended children/year aged from seven month to 12 years old, 450 serum samples were randomly collected from September/2004 to September/2005. A questionnaire was used to evaluate epidemiological, clinical and hematological data. An ELISA using Toxocara canis larval excretory-secretory products as antigen detected 130 (28.8%) positive sera, mainly between children from seven month to five years old (p = 0.0016). Significant correlation was observed between positive serology for Toxocara, and frequent playing in sandbox at school or daycare center (p = 0.011) and the presence of a cat at home (p = 0.056). From the families, 50% were dog owners which exposed soil backyards. Eosinophilia (p = 0.776), and signs and symptoms analyzed (fever p = 0.992, pneumonia p = 0.289, cold-like symptoms p = 0.277, cough p = 0.783, gastrointestinal problems p = 0.877, migraine p = 0.979, abdominal pain p = 0.965, joint pain p = 0.686 and skin rash p = 0.105) could not be related to the presence of anti-Toxocara antibodies. Therefore, two asthmatics children showed titles of 1:10,240 and accentuated eosinophilia (p = 0.0001). The authors emphasize the needs of prevention activities.

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Attribution of high resolution streamflow trends in Western Austria – an approach based on climate and discharge station data

Hydrology and Earth System Sciences ◽

10.5194/hess-19-1225-2015 ◽

2015 ◽

Vol 19 (3) ◽

pp. 1225-1245 ◽

Cited By ~ 15

Author(s):

C. Kormann ◽

T. Francke ◽

M. Renner ◽

A. Bronstert

Keyword(s):

Freezing Point ◽

Snow Accumulation ◽

Lower Altitude ◽

Study Region ◽

Daily Streamflow ◽

Streamflow Data ◽

The One ◽

Streamflow Trend ◽

Streamflow Trends

Abstract. The results of streamflow trend studies are often characterized by mostly insignificant trends and inexplicable spatial patterns. In our study region, Western Austria, this applies especially for trends of annually averaged runoff. However, analysing the altitudinal aspect, we found that there is a trend gradient from higher-altitude to lower-altitude stations, i.e. a pattern of mostly positive annual trends at higher stations and negative ones at lower stations. At mid-altitudes, the trends are mostly insignificant. Here we hypothesize that the streamflow trends are caused by the following two main processes: on the one hand, melting glaciers produce excess runoff at higher-altitude watersheds. On the other hand, rising temperatures potentially alter hydrological conditions in terms of less snowfall, higher infiltration, enhanced evapotranspiration, etc., which in turn results in decreasing streamflow trends at lower-altitude watersheds. However, these patterns are masked at mid-altitudes because the resulting positive and negative trends balance each other. To support these hypotheses, we attempted to attribute the detected trends to specific causes. For this purpose, we analysed trends of filtered daily streamflow data, as the causes for these changes might be restricted to a smaller temporal scale than the annual one. This allowed for the explicit determination of the exact days of year (DOYs) when certain streamflow trends emerge, which were then linked with the corresponding DOYs of the trends and characteristic dates of other observed variables, e.g. the average DOY when temperature crosses the freezing point in spring. Based on these analyses, an empirical statistical model was derived that was able to simulate daily streamflow trends sufficiently well. Analyses of subdaily streamflow changes provided additional insights. Finally, the present study supports many modelling approaches in the literature which found out that the main drivers of alpine streamflow changes are increased glacial melt, earlier snowmelt and lower snow accumulation in wintertime.

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Serological reactivity of different antigenic preparations of Leishmania (Leishmania) amazonensis and the Leishmania braziliensis complex

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86822008000200001 ◽

2008 ◽

Vol 41 (2) ◽

pp. 135-141 ◽

Cited By ~ 11

Author(s):

Adriano Gomes-Silva ◽

Maria Aparecida Souza ◽

Sandra Regina Afonso-Cardoso ◽

Lívia Resende Andrade ◽

Reynaldo Dietze ◽

...

Keyword(s):

Visceral Leishmaniasis ◽

Affinity Chromatography ◽

Healthy Volunteers ◽

Concanavalin A ◽

Leishmania Amazonensis ◽

Leishmania Braziliensis ◽

Elisa Assay ◽

Serum Samples ◽

Sensitivity Range ◽

Serological Reactivity

Total antigen from Leishmania (Leishmania) amazonensis and isolates from the Leishmania braziliensis complex, along with their respective antigenic fractions obtained by affinity chromatography on concanavalin-A-Sepharose and jacalin-agarose columns evaluated using immunoenzymatic ELISA assay. For this, serum samples from 229 patients were used, grouped as American tegmental leishmaniasis (nº=58), visceral leishmaniasis (nº=28), Chagas disease (nº=49), malaria (nº=32), tuberculosis (nº=13) and healthy volunteers (nº=49). Samples from American tegmentary leishmaniasis showed higher reactivity with antigens isolated from the Leishmania braziliensis complex than with antigens from Leishmania amazonensis (p<0.001). ELISA assays showed a sensitivity range from 60% to 95% with antigens isolated from the Leishmania braziliensis complex. There was marked nonspecific reactivity among serum samples with the use of antigenic fractions binding with concanavalin-A and jacalin from both Leishmania complexes, in comparison with other antigens (p<0.001). The results presented in this study suggest that the use of homologous antigens increases the efficiency of anti-Leishmania immunoglobulin detection, which may be very valuable for diagnostic purposes.

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