Evaluation of rK39 rapid diagnostic tests for canine visceral leishmaniasis : longitudinal study and meta-analysis

Canine visceral leishmaniasis is a vector-borne disease caused by the intracellular parasite Leishmania infantum. It is an important veterinary disease, and dogs are also the main animal reservoir for human infection. The disease is widespread in the Mediterranean area, and parts of Asia and South and Central America, and is potentially fatal in both dogs and humans unless treated. Diagnosis of canine infections requires serological or molecular tests. Detection of infection in dogs is important prior to treatment, and in epidemiological studies and control programmes, and a sensitive and specific rapid diagnostic test would be very useful. Rapid diagnostic tests (RDTs) have been developed, but their diagnostic performance has been reported to be variable. We evaluated the sensitivity of a RDT based on serological detection of the rK39 antigen in a cohort of naturally infected Brazilian dogs. The sensitivity of the test to detect infection was relatively low, but increased with time since infection and the severity of infection. We then carried out a meta-analysis of published studies of rK39 RDTs, evaluating the sensitivity to detect disease and infection. The results suggest that rK39 RDTs may be useful in a veterinary clinical setting, but the sensitivity to detect infection is too low for operational control programmes

Comparative Study of rK39 Leishmania Antigen for Serodiagnosis of Visceral Leishmaniasis: Systematic Review with Meta-Analysis

Visceral Leishmaniasis (VL) is a neglected tropical disease for which serodiagnostic tests are available, but not yet widely implemented in rural areas. The rK39 recombinant protein is derived from a kinesin-like protein of parasites belonging to the Leishmania donovani complex, and has been used in the last two decades for the serodiagnosis of VL. We present here a systematic review and meta-analysis of studies evaluating serologic assays (rK39 strip-test, rK39 ELISA, Direct Agglutination Test [DAT], Indirect Immunofluorescence test [IFAT] and ELISA with a promastigote antigen preparation [p-ELISA]) to diagnose VL to determine the accuracy of rK39 antigen in comparison to the use of other antigen preparations. Fourteen papers fulfilled the inclusion and exclusion selection criteria. The summarized sensitivity for the rK39-ELISA was 92% followed by IFAT 88% and p-ELISA 87%. The summarized specificity for the three diagnostic tests was 81%, 90%, and 77%. Studies comparing the rK39 strip test with DAT found a similar sensitivity (94%) and specificity (89%). However, the rK39 strip test was more specific than the IFAT and p-ELISA. In conclusion, we found the rK39 protein used either in a strip test or in an ELISA is a good choice for the serodiagnosis of VL

Effects of mycotoxins on hormone production in primary Leydig cells isolated from pigs

Proceedings 2013, pp. 172-178Mycotoxins are toxins produced by fungi in many agricultural products worldwide either pre- or post-harvesting. Fusarium species are among the most researched plant pathogenic fungi (1) that produce a number of mycotoxins including DON, NIV, T-2, HT-2, fumonisins, ZEN and its metabolites α- and β-zearalenol (2). Some fungi are able to produce more than one mycotoxin, but also multiple fungi can contaminate the same crop (3). Natural co-occurrence of Fusarium mycotoxins increases the concern on the exposure to mixtures of mycotoxins e.g. co-occurrence of DON/ ZEN/ T-2/ HT-2 (4,5). Exposure to mycotoxins can result in a variety of health effects, ranging from acute toxic response to potential long-term carcinogenic and teratogenic effects (6). Effects of mycotoxins on reproduction in livestock have been reviewed extensively (7). ZEN ingestion in animals is associated with anestrus, abortion, increased embryonic and fetal death, increased stillbirths, reduced milk production, hyperestrogenism and poor quality semen (7,8) In vitro, ZEN increased the progesterone production in porcine granulosa cells (9). ZEN and α-ZOL have potent estrogenic effects and promote hormone production in H295R cells (10). DON, T-2 and HT-2 reduced cell viability, inhibit steroidogenesis and alter expression of steroidogenic genes in human adrenocarcinoma (H295R) cells (11) Leydig cells are the testicular endocrine cells capable of producing steroid hormones. Pig Leydig cell culture is a good in vitro model to study steroidogenesis and screen effects of some chemicals (12,13). We hypothesize that F. graminearum culture extracts contain a mixture of naturally co-occurring mycotoxins that are able to cause deleterious effects in vitro in Leydig cells

Effects of mycotoxins on hormone production in primary Leydig cells isolated from pigs

Proceedings 2013, pp. 172-178Mycotoxins are toxins produced by fungi in many agricultural products worldwide either pre- or post-harvesting. Fusarium species are among the most researched plant pathogenic fungi (1) that produce a number of mycotoxins including DON, NIV, T-2, HT-2, fumonisins, ZEN and its metabolites α- and β-zearalenol (2). Some fungi are able to produce more than one mycotoxin, but also multiple fungi can contaminate the same crop (3). Natural co-occurrence of Fusarium mycotoxins increases the concern on the exposure to mixtures of mycotoxins e.g. co-occurrence of DON/ ZEN/ T-2/ HT-2 (4,5). Exposure to mycotoxins can result in a variety of health effects, ranging from acute toxic response to potential long-term carcinogenic and teratogenic effects (6). Effects of mycotoxins on reproduction in livestock have been reviewed extensively (7). ZEN ingestion in animals is associated with anestrus, abortion, increased embryonic and fetal death, increased stillbirths, reduced milk production, hyperestrogenism and poor quality semen (7,8) In vitro, ZEN increased the progesterone production in porcine granulosa cells (9). ZEN and α-ZOL have potent estrogenic effects and promote hormone production in H295R cells (10). DON, T-2 and HT-2 reduced cell viability, inhibit steroidogenesis and alter expression of steroidogenic genes in human adrenocarcinoma (H295R) cells (11) Leydig cells are the testicular endocrine cells capable of producing steroid hormones. Pig Leydig cell culture is a good in vitro model to study steroidogenesis and screen effects of some chemicals (12,13). We hypothesize that F. graminearum culture extracts contain a mixture of naturally co-occurring mycotoxins that are able to cause deleterious effects in vitro in Leydig cells

Effects of mycotoxins on hormone production in primary Leydig cells isolated from pigs

Proceedings 2013, pp. 172-178Mycotoxins are toxins produced by fungi in many agricultural products worldwide either pre- or post-harvesting. Fusarium species are among the most researched plant pathogenic fungi (1) that produce a number of mycotoxins including DON, NIV, T-2, HT-2, fumonisins, ZEN and its metabolites α- and β-zearalenol (2). Some fungi are able to produce more than one mycotoxin, but also multiple fungi can contaminate the same crop (3). Natural co-occurrence of Fusarium mycotoxins increases the concern on the exposure to mixtures of mycotoxins e.g. co-occurrence of DON/ ZEN/ T-2/ HT-2 (4,5). Exposure to mycotoxins can result in a variety of health effects, ranging from acute toxic response to potential long-term carcinogenic and teratogenic effects (6). Effects of mycotoxins on reproduction in livestock have been reviewed extensively (7). ZEN ingestion in animals is associated with anestrus, abortion, increased embryonic and fetal death, increased stillbirths, reduced milk production, hyperestrogenism and poor quality semen (7,8) In vitro, ZEN increased the progesterone production in porcine granulosa cells (9). ZEN and α-ZOL have potent estrogenic effects and promote hormone production in H295R cells (10). DON, T-2 and HT-2 reduced cell viability, inhibit steroidogenesis and alter expression of steroidogenic genes in human adrenocarcinoma (H295R) cells (11) Leydig cells are the testicular endocrine cells capable of producing steroid hormones. Pig Leydig cell culture is a good in vitro model to study steroidogenesis and screen effects of some chemicals (12,13). We hypothesize that F. graminearum culture extracts contain a mixture of naturally co-occurring mycotoxins that are able to cause deleterious effects in vitro in Leydig cells

Effects of mycotoxins on hormone production in primary Leydig cells isolated from pigs

Proceedings 2013, pp. 172-178Mycotoxins are toxins produced by fungi in many agricultural products worldwide either pre- or post-harvesting. Fusarium species are among the most researched plant pathogenic fungi (1) that produce a number of mycotoxins including DON, NIV, T-2, HT-2, fumonisins, ZEN and its metabolites α- and β-zearalenol (2). Some fungi are able to produce more than one mycotoxin, but also multiple fungi can contaminate the same crop (3). Natural co-occurrence of Fusarium mycotoxins increases the concern on the exposure to mixtures of mycotoxins e.g. co-occurrence of DON/ ZEN/ T-2/ HT-2 (4,5). Exposure to mycotoxins can result in a variety of health effects, ranging from acute toxic response to potential long-term carcinogenic and teratogenic effects (6). Effects of mycotoxins on reproduction in livestock have been reviewed extensively (7). ZEN ingestion in animals is associated with anestrus, abortion, increased embryonic and fetal death, increased stillbirths, reduced milk production, hyperestrogenism and poor quality semen (7,8) In vitro, ZEN increased the progesterone production in porcine granulosa cells (9). ZEN and α-ZOL have potent estrogenic effects and promote hormone production in H295R cells (10). DON, T-2 and HT-2 reduced cell viability, inhibit steroidogenesis and alter expression of steroidogenic genes in human adrenocarcinoma (H295R) cells (11) Leydig cells are the testicular endocrine cells capable of producing steroid hormones. Pig Leydig cell culture is a good in vitro model to study steroidogenesis and screen effects of some chemicals (12,13). We hypothesize that F. graminearum culture extracts contain a mixture of naturally co-occurring mycotoxins that are able to cause deleterious effects in vitro in Leydig cells

Effects of mycotoxins on hormone production in primary Leydig cells isolated from pigs

Proceedings 2013, pp. 172-178Mycotoxins are toxins produced by fungi in many agricultural products worldwide either pre- or post-harvesting. Fusarium species are among the most researched plant pathogenic fungi (1) that produce a number of mycotoxins including DON, NIV, T-2, HT-2, fumonisins, ZEN and its metabolites α- and β-zearalenol (2). Some fungi are able to produce more than one mycotoxin, but also multiple fungi can contaminate the same crop (3). Natural co-occurrence of Fusarium mycotoxins increases the concern on the exposure to mixtures of mycotoxins e.g. co-occurrence of DON/ ZEN/ T-2/ HT-2 (4,5). Exposure to mycotoxins can result in a variety of health effects, ranging from acute toxic response to potential long-term carcinogenic and teratogenic effects (6). Effects of mycotoxins on reproduction in livestock have been reviewed extensively (7). ZEN ingestion in animals is associated with anestrus, abortion, increased embryonic and fetal death, increased stillbirths, reduced milk production, hyperestrogenism and poor quality semen (7,8) In vitro, ZEN increased the progesterone production in porcine granulosa cells (9). ZEN and α-ZOL have potent estrogenic effects and promote hormone production in H295R cells (10). DON, T-2 and HT-2 reduced cell viability, inhibit steroidogenesis and alter expression of steroidogenic genes in human adrenocarcinoma (H295R) cells (11) Leydig cells are the testicular endocrine cells capable of producing steroid hormones. Pig Leydig cell culture is a good in vitro model to study steroidogenesis and screen effects of some chemicals (12,13). We hypothesize that F. graminearum culture extracts contain a mixture of naturally co-occurring mycotoxins that are able to cause deleterious effects in vitro in Leydig cells

Effects of mycotoxins on hormone production in primary Leydig cells isolated from pigs

Proceedings 2013, pp. 172-178Mycotoxins are toxins produced by fungi in many agricultural products worldwide either pre- or post-harvesting. Fusarium species are among the most researched plant pathogenic fungi (1) that produce a number of mycotoxins including DON, NIV, T-2, HT-2, fumonisins, ZEN and its metabolites α- and β-zearalenol (2). Some fungi are able to produce more than one mycotoxin, but also multiple fungi can contaminate the same crop (3). Natural co-occurrence of Fusarium mycotoxins increases the concern on the exposure to mixtures of mycotoxins e.g. co-occurrence of DON/ ZEN/ T-2/ HT-2 (4,5). Exposure to mycotoxins can result in a variety of health effects, ranging from acute toxic response to potential long-term carcinogenic and teratogenic effects (6). Effects of mycotoxins on reproduction in livestock have been reviewed extensively (7). ZEN ingestion in animals is associated with anestrus, abortion, increased embryonic and fetal death, increased stillbirths, reduced milk production, hyperestrogenism and poor quality semen (7,8) In vitro, ZEN increased the progesterone production in porcine granulosa cells (9). ZEN and α-ZOL have potent estrogenic effects and promote hormone production in H295R cells (10). DON, T-2 and HT-2 reduced cell viability, inhibit steroidogenesis and alter expression of steroidogenic genes in human adrenocarcinoma (H295R) cells (11) Leydig cells are the testicular endocrine cells capable of producing steroid hormones. Pig Leydig cell culture is a good in vitro model to study steroidogenesis and screen effects of some chemicals (12,13). We hypothesize that F. graminearum culture extracts contain a mixture of naturally co-occurring mycotoxins that are able to cause deleterious effects in vitro in Leydig cells