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1.
Front Cell Infect Microbiol ; 14: 1384393, 2024.
Article in English | MEDLINE | ID: mdl-38720960

ABSTRACT

The clinical consequences of toxoplasmosis are greatly dependent on the Toxoplasma gondii strain causing the infection. To better understand its epidemiology and design appropriate control strategies, it is important to determine the strain present in infected animals. Serotyping methods are based on the detection of antibodies that react against segments of antigenic proteins presenting strain-specific polymorphic variations, offering a cost-effective, sensitive, and non-invasive alternative to genotyping techniques. Herein, we evaluated the applicability of a panel of peptides previously characterized in mice and humans to serotype sheep and pigs. To this end, we used 51 serum samples from experimentally infected ewes (32 type II and 19 type III), 20 sheep samples from naturally infected sheep where the causative strain was genotyped (18 type II and 2 type III), and 40 serum samples from experimentally infected pigs (22 type II and 18 type III). Our ELISA test results showed that a combination of GRA peptide homologous pairs can discriminate infections caused by type II and III strains of T. gondii in sheep and pigs. Namely, the GRA3-I/III-43 vs. GRA3-II-43, GRA6-I/III-213 vs. GRA6-II-214 and GRA6-III-44 vs. GRA6-II-44 ratios showed a statistically significant predominance of the respective strain-type peptide in sheep, while in pigs, in addition to these three peptide pairs, GRA7-II-224 vs. GRA7-III-224 also showed promising results. Notably, the GRA6-44 pair, which was previously deemed inefficient in mice and humans, showed a high prediction capacity, especially in sheep. By contrast, GRA5-38 peptides failed to correctly predict the strain type in most sheep and pig samples, underpinning the notion that individual standardization is needed for each animal species. Finally, we recommend analyzing for each animal at least 2 samples taken at different time points to confirm the obtained results.


Subject(s)
Antigens, Protozoan , Serotyping , Sheep Diseases , Swine Diseases , Toxoplasmosis, Animal , Animals , Antibodies, Protozoan/blood , Antigens, Protozoan/genetics , Antigens, Protozoan/immunology , Enzyme-Linked Immunosorbent Assay/methods , Genotype , Peptides/immunology , Serotyping/methods , Sheep , Sheep Diseases/parasitology , Sheep Diseases/diagnosis , Swine , Swine Diseases/parasitology , Swine Diseases/diagnosis , Toxoplasmosis, Animal/diagnosis , Toxoplasmosis, Animal/parasitology
2.
J Phycol ; 59(4): 725-737, 2023 08.
Article in English | MEDLINE | ID: mdl-37232027

ABSTRACT

Coolia species are epiphytic and benthic dinoflagellates with a cosmopolitan distribution in tropical and subtropical areas. In the austral summer of 2016, during a survey in Bahía Calderilla, a dinoflagellate of the genus Coolia was detected in macroalgae samples, and a clonal culture was established. Subsequently, the cultured cells were observed by scanning electron microscopy (SEM) and identified as C. malayensis based on their morphological characteristics. Phylogenetic analyses based on the LSU rDNA D1/D2 regions confirmed that strain D005-1 corresponded to C. malayensis and clustered with strains isolated from New Zealand, Mexico, and Asia Pacific countries. Although the strain D005-1 culture did not contain yessotoxin (YTX), cooliatoxin, 44-methyl gambierone, or its analogs in detectable amounts by LC-MS/MS, more research is needed to evaluate its toxicity and to determine the possible impact of C. malayensis in northern Chilean waters.


Subject(s)
Dinoflagellida , Environmental Monitoring , Dinoflagellida/classification , Pacific Ocean , Tandem Mass Spectrometry , Seaweed , Microscopy, Electron, Scanning
3.
Toxins (Basel) ; 13(6)2021 06 09.
Article in English | MEDLINE | ID: mdl-34207719

ABSTRACT

The Peruvian sea is one of the most productive ecosystems in the world. Phytoplankton production provides food for fish, mammals, mollusks and birds. This trophic network is affected by the presence of toxic phytoplankton species. In July 2017, samples of phytoplankton were obtained from Paracas Bay, an important zone for scallop (Argopecten purpuratus) aquaculture in Peru. Morphological analysis revealed the presence of the genus Pseudo-nitzschia, which was isolated and cultivated in laboratory conditions. Subsequently, the monoclonal cultures were observed by scanning electron microscopy (SEM), and identified as P. multistriata, based on both the morphological characteristics, and internal transcribed spacers region (ITS2) sequence phylogenetic analysis. Toxin analysis using liquid chromatography (LC) with high-resolution mass spectrometry (HRMS) revealed the presence of domoic acid (DA) with an estimated amount of 0.004 to 0.010 pg cell-1. This is the first report of DA from the coastal waters of Peru and its detection in P. multistriata indicates that it is a potential risk. Based on our results, routine monitoring of this genus should be considered in order to ensure public health.


Subject(s)
Diatoms/metabolism , Kainic Acid/analogs & derivatives , Marine Toxins/metabolism , Neurotoxins/metabolism , Phytoplankton/metabolism , Bays , Diatoms/genetics , Environmental Monitoring , Kainic Acid/metabolism , Peru , Phylogeny , Phytoplankton/genetics
4.
Toxins (Basel) ; 12(11)2020 11 03.
Article in English | MEDLINE | ID: mdl-33153112

ABSTRACT

Domoic acid (DA), the main toxin responsible for Amnesic Shellfish Poisoning, frequently affects the marine resources of Chile and other countries across the South Pacific, thus becoming a risk for human health. One of the affected resources is the scallop Argopecten purpuratus. Even though this species has a high commercial importance in Northern Chile and Peru, the characteristics of its DA depuration are not known. In this work, the DA depuration was studied by means of two experiments: one in controlled (laboratory) and another in natural conditions. All organs of A. purpuratus depurated the toxin very quickly in both experiments. In some organs, an increase or a very small decrease of toxin was detected in the early depuration steps. Several models were used to describe this kinetics. The one that included toxin transfer between organs and independent depuration from each organ was the model that best fit the data. It seems, therefore, that the DA in this species is quickly transferred from the digestive gland to all other organs, which release it into the environment. Physiological differences in the two experiments have been shown to have some effect on the depuration from each organ but the actual reasons are still unknown.


Subject(s)
Digestive System/metabolism , Kainic Acid/analogs & derivatives , Marine Toxins/metabolism , Pectinidae/metabolism , Seafood , Shellfish Poisoning , Animals , Body Burden , Kainic Acid/metabolism , Kainic Acid/toxicity , Kinetics , Marine Toxins/toxicity , Seafood/adverse effects , Tissue Distribution , Toxicokinetics
8.
Bol Med Hosp Infant Mex ; 77(1): 34-37, 2020.
Article in English | MEDLINE | ID: mdl-32115584

ABSTRACT

Background: Epicardial pacemaker is the preferred method for newborns and children under 10 kg of weight. However, its placement presents a high rate of premature failure. Case report: The case of an infant requiring placement of pacemaker by congenital atrioventricular block with prenatal diagnosis is described. The patient showed critical stenosis of the superior vena cava as a complication. Interventional resolution using a stent at the site of stenosis corrected the superior vena cava syndrome effectively. Conclusions: This case represents a clinically viable alternative for the treatment of superior vena cava syndrome, which can be used after other conventional therapies have failed.


Introducción: El marcapasos epicárdico es el método preferido en recién nacidos y niños que pesan menos de 10 kg. Sin embargo, su colocación cuenta con una alta incidencia de fracaso prematuro. Caso clínico: Se presenta el caso de un lactante que requirió la colocación de un marcapasos por bloqueo atrioventricular congénito diagnosticado prenatalmente. El paciente presentaba estenosis crítica de la vena cava superior como complicación secundaria a los cables del marcapasos. La resolución intervencionista mediante un stent en el sitio de estenosis corrigió el síndrome de vena cava superior de forma efectiva. Conclusiones: Este caso representa una alternativa clínicamente viable en el tratamiento del síndrome de vena cava superior, que puede emplearse después de otras terapias convencionales que hayan fallado.


Subject(s)
Atrioventricular Block/therapy , Pacemaker, Artificial , Stents , Superior Vena Cava Syndrome/surgery , Atrioventricular Block/congenital , Female , Humans , Infant , Superior Vena Cava Syndrome/etiology , Vena Cava, Superior/pathology
9.
Bol. méd. Hosp. Infant. Méx ; 77(1): 34-37, ene.-feb. 2020. graf
Article in Spanish | LILACS | ID: biblio-1153227

ABSTRACT

Resumen Introducción: El marcapasos epicárdico es el método preferido en recién nacidos y niños que pesan menos de 10 kg. Sin embargo, su colocación cuenta con una alta incidencia de fracaso prematuro. Caso clínico: Se presenta el caso de un lactante que requirió la colocación de un marcapasos por bloqueo atrioventricular congénito diagnosticado prenatalmente. El paciente presentaba estenosis crítica de la vena cava superior como complicación secundaria a los cables del marcapasos. La resolución intervencionista mediante un stent en el sitio de estenosis corrigió el síndrome de vena cava superior de forma efectiva. Conclusiones: Este caso representa una alternativa clínicamente viable en el tratamiento del síndrome de vena cava superior, que puede emplearse después de otras terapias convencionales que hayan fallado.


Abstract Background: Epicardial pacemaker is the preferred method for newborns and children under 10 kg of weight. However, its placement presents a high rate of premature failure. Case report: The case of an infant requiring placement of pacemaker by congenital atrioventricular block with prenatal diagnosis is described. The patient showed critical stenosis of the superior vena cava as a complication. Interventional resolution using a stent at the site of stenosis corrected the superior vena cava syndrome effectively. Conclusions: This case represents a clinically viable alternative for the treatment of superior vena cava syndrome, which can be used after other conventional therapies have failed.


Subject(s)
Female , Humans , Infant , Pacemaker, Artificial , Superior Vena Cava Syndrome/surgery , Stents , Atrioventricular Block/therapy , Vena Cava, Superior/pathology , Superior Vena Cava Syndrome/etiology , Atrioventricular Block/congenital
10.
Toxins (Basel) ; 11(4)2019 03 29.
Article in English | MEDLINE | ID: mdl-30934869

ABSTRACT

In late February 2016, a harmful algal bloom (HAB) of Alexandrium catenella was detected in southern Chiloé, leading to the banning of shellfish harvesting in an extended geographical area (~500 km). On April 24, 2016, this bloom produced a massive beaching (an accumulation on the beach surface of dead or impaired organisms which were drifted ashore) of surf clams Mesodesma donacium in Cucao Bay, Chiloé. To determine the effect of paralytic shellfish poisoning (PSP) toxins in M. donacium, samples were taken from Cucao during the third massive beaching detected on May 3, 2016. Whole tissue toxicity evidence a high interindividual variability with values which ranged from 1008 to 8763 µg STX eq 100 g-1 and with a toxin profile dominated by GTX3, GTX1, GTX2, GTX4, and neoSTX. Individuals were dissected into digestive gland (DG), foot (FT), adductor muscle (MU), and other body fractions (OBF), and histopathological and toxin analyses were carried out on the obtained fractions. Some pathological conditions were observed in gill and digestive gland of 40⁻50% of the individuals that correspond to hemocyte aggregation and haemocytic infiltration, respectively. The most toxic tissue was DG (2221 µg STX eq 100 g-1), followed by OBF (710 µg STX eq 100 g-1), FT (297 µg STX eq 100 g-1), and MU (314 µg STX eq 100 g-1). The observed surf clam mortality seems to have been mainly due to the desiccation caused by the incapability of the clams to burrow. Considering the available information of the monitoring program and taking into account that this episode was the first detected along the open coast of the Pacific Ocean in southern Chiloé, it is very likely that the M. donacium population from Cucao Bay has not had a recurrent exposition to A. catenella and, consequently, that it has not been subjected to high selective pressure for PSP resistance. However, more research is needed to determine the effects of PSP toxins on behavioral and physiological responses, nerve sensitivity, and genetic/molecular basis for the resistance or sensitivity of M. donacium.


Subject(s)
Bivalvia/chemistry , Bivalvia/drug effects , Dinoflagellida , Harmful Algal Bloom , Marine Toxins/analysis , Marine Toxins/toxicity , Animals , Biological Monitoring , Chile , Hemocytes , Shellfish Poisoning
11.
Toxins (Basel) ; 10(8)2018 08 04.
Article in English | MEDLINE | ID: mdl-30081538

ABSTRACT

Surf clams, Mesodesma donacium, were shown to accumulate toxins from Dinophysis acuminata blooms. Only pectenotoxin 2 (PTX2) and some of its derivatives were found, and no toxins from the okadaic acid group were detected. PTX2 seems to be transformed to PTX2 seco-acid (PTX2sa), which was found in concentrations more than ten-fold those of PTX2. The seco-acid was transformed to acyl-derivatives by esterification with different fatty acids. The estimated amount of these derivatives in the mollusks was much higher than that of PTX2. Most esters were originated by even carbon chain fatty acids, but some originated by odd carbon number were also found in noticeable concentrations. Some peaks of toxin in the bivalves did not coincide with those of Dinophysis abundance, suggesting that there were large differences in toxin content per cell among the populations that developed throughout the year. The observed depuration (from the digestive gland) was fast (more than 0.2 day-1), and was faster for PTX2 than for PTX2sa, which in turn was faster than that of esters of PTX2sa. PTX2 and PTX2sa were distributed nearly equally between the digestive gland and the remaining tissues, but less than 5% of the palmytoyl-esters were found outside the digestive gland.


Subject(s)
Bivalvia/metabolism , Dinoflagellida , Furans/metabolism , Marine Toxins/metabolism , Pyrans/metabolism , Animals , Biotransformation , Macrolides
12.
Harmful Algae ; 58: 8-15, 2016 09.
Article in English | MEDLINE | ID: mdl-28073462

ABSTRACT

In summer 2009, during a survey in Bahía Mejillones, a dense bloom of a dinoflagellate from the genus Gonyaulax was detected, as well as the presence of yessotoxin. Phytoplankton samples were analyzed in detail by light and scanning electron microscopy (SEM), revealing the presence of Gonyaulax taylorii. Morphological examination showed that the cells in the bloom fit in Gonyaulax jollifei Murray et Whitting sensu Dodge, subsequently classified as Gonyaulax taylorii by Carbonell-Moore. In this context, some inconsistencies have been found in regard to the holotype; the plate 1"' appears as two plates, 1‴ and 2‴, showing a suture that does not exist in Dodge's figure of G. jollifei, from where the holotype was drawn, nor within the samples collected. Therefore, this plate has been originally described erroneously as two plates named 1"' and 2"' instead of only one named 1‴. After this correction, this species has five instead of six postcingular plates. For this reason, the description of this species must be emended. Phytoplankton net samples were found to contain yessotoxin and homoyessotoxin, with concentrations below 1pgcell-1. The present study identifies, therefore, the dinoflagellate G. taylorii as a new source of yessotoxins.


Subject(s)
Dinoflagellida/classification , Oxocins/metabolism , Chile , Dinoflagellida/ultrastructure , Microscopy, Electron, Scanning , Mollusk Venoms , Phytoplankton/classification , Phytoplankton/metabolism , Phytoplankton/ultrastructure , Species Specificity
13.
Toxicon ; 102: 1-7, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26003793

ABSTRACT

In northern Chile, domoic acid (DA) has been detected in several bivalve species. In Mesodesma donacium, one of the most important commercial species for local fishermen, no information is available on depuration, or on the anatomical distribution of this toxin and its potential use as a palliative measure to minimize the consequences of ASP outbreaks. Deputation of DA is very fast in M. donacium, and can be adequately described by means of a two-compartment model. The estimated rates for the first and second compartments were 1.27 d(-1) and 0.24 d(-1), respectively, with a transfer rate between compartments of 0.75. Having high depuration rates protects this species from being affected by Pseudo-nitzschia blooms for an extended period of time. Taking this into account, the time in which the bivalves are unsafe for consumers is very short, and therefore the economic losses that could result by the DA outbreaks in local fisheries should be moderate. In relation to anatomical distribution, at least during the uptake phase, the toxin was evenly distributed within the soft tissues, with a total toxin burden corresponding to 27%, 32% and 41% for Digestive Gland (DG), Foot (FT) and Other Body Fractions (OBF), respectively. Since the contribution of each organ to the toxin concentration is a function of both weight contribution and toxin burden, the pattern of toxin distribution showed the following trend: "all other body fractions" (OBF) > Foot (FT) > Digestive Gland (DG). Thus, the highest concentration of DA, with a contribution close to 72%, corresponds to the edible tissues (OBF + FT), while the DG (non-edible tissue) only contributes the remaining 28%. Consequently, in view of the anatomical distribution of domoic acid in M. donacium, the elimination of the digestive gland does not substantially reduce the toxicity of the final product and therefore selective evisceration would not improve their quality for human consumption.


Subject(s)
Bivalvia/chemistry , Diatoms/chemistry , Kainic Acid/analogs & derivatives , Marine Toxins/analysis , Marine Toxins/metabolism , Animals , Biological Transport , Bivalvia/anatomy & histology , Chile , Kainic Acid/metabolism , Tissue Distribution
14.
Electron. j. biotechnol ; 15(5): 19-19, Sept. 2012. ilus, tab
Article in English | LILACS | ID: lil-657678

ABSTRACT

Adaptation and selection of Arthrospira platensis strains, for cultivation in brackish water with excess boron (B) in the Lluta Valley can become an interesting alternative that would allow to extend these cultures to areas that possess the environmental conditions, but that lack the fresh water needed to do it. Strains TX98 and P88 were evaluated in laboratory conditions with three different media of brackish water and with the white medium, the Zarrouk modified medium (MZM). The growing media with brackish water with a B concentration present in the Lluta River of 20 mgL-1 (B20) and medium with 30 mgL-1 (B30), and 10 mg L-1 of B (B10). The effect of the different media on the growing parameters with a culture temperature of 25 +/- 1ºC in the three treatments, strains TX98 and P88 triplicate, Arthrospira platensis, showed tolerance. It was statistically determined that in the growth, the two strains, the three treatments and in the interrelation of both there were significant differences (p < 0.05). The TX98 strain reached a concentration of 1.139 g L-1 (dry weight) in brackish water with medium B20. Therefore, the highest rate of specific growth (μmax) was obtained with the TX98 strain grown in the brackish medium B30 and the lowest duplication time (0.597 days). Cells grown in brackish water with B had a slightly biochemically modified composition with the white, in relation to the protein content, in the cases in which there are differences in the B content, specifically B30 treatment. For the culture with brackish water from the Lluta River, the TX98 strain is recommended with 10 mg of B using a laboratory to pilot scale.


Subject(s)
Boron , Microalgae , Saline Waters , Spirulina , Chile , Cyanobacteria
15.
Toxicon ; 55(2-3): 638-41, 2010.
Article in English | MEDLINE | ID: mdl-19631679

ABSTRACT

In an attempt to evaluate the risk for human consumption associated to the accumulation of lipophilic toxins by two commercially important bivalves: macha (Mesodesma donacium) and clam (Mulinia edulis) in Coquimbo Bay (Chile), monitoring of these species was carried out from March to September 2008. The samples were analyzed by liquid chromatography-mass spectrometry (LC-MS) to detect okadaic acid, dinophysistoxins, pectenotoxins, azaspiracids, yessotoxins and spirolides. Low levels of Azaspiracid-1 and 13-desmethyl C spirolide were found in both species. The toxins were detected at different dates throughout the monitoring period and in some cases both toxins were detected in the same sample. In all cases, the concentration of the toxins was below the limit of quantification of the technique used and therefore these detections are only indicative of a potential risk. This is the first report of the occurrence of these groups of toxins in Chile and suggests that it is necessary to monitor routinely these substances to warrant public health and shellfish exportations.


Subject(s)
Bivalvia/chemistry , Marine Toxins/analysis , Shellfish/analysis , Spiro Compounds/analysis , Animals , Chile , Lipids/chemistry , Mass Spectrometry , Tissue Extracts/chemistry
16.
Toxicon ; 54(6): 754-62, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19505493

ABSTRACT

The tunicate Pyura chilensis (Molina, 1782); Phylum Chordata; Subphylum Urochordata; Class Ascidiacea, common local name "piure" or sea squirt; a filter-feeder (plankton and suspended particles) sessile species; may play an important role in monitoring domoic acid (DA) the principal toxic component of Amnesic Shellfish Poisoning (ASP). Significant DA concentrations have been determined in tunicate samples, collected during a recent ASP outbreak in Bahía Inglesa, an important scallop (Argopecten purpuratus) farming area. Several infaunal species were tested for the presence of DA, in addition to the usual scallop monitoring programme. DA was found at sub-toxic levels in filtering bivalves such as mussels (Mytilus chilensis), large mussels (Aulacomya ater) and clams (Protothaca thaca) (6.4, 5.4 and 4.7 microg DA/g tissue respectively). Of particular interest was the observation of significant accumulations of toxic Pseudo-nitzschia sp. diatoms in the internal siphon and atrium spaces of the tunicate. Toxin distribution within major tunicate organs was heterogeneous with 8.7-15.5 microg DA/g in edible tissues, 14.9-17.9 microg DA/g in the fecal material and 13.6-32.7 microg DA/g in the gut content. DA was determined by HPLC-UV and confirmed by diode-array detection and LC-MS/MS analysis. This is the first report of the presence of DA in a tunicate that is regularly consumed by coastal populations. These results confirm the need to include these organisms in sanitation programs for marine toxins.


Subject(s)
Diatoms/growth & development , Kainic Acid/analogs & derivatives , Urochordata , Animals , Kainic Acid/analysis , Kainic Acid/toxicity
17.
Toxicon ; 49(5): 710-6, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17189646

ABSTRACT

A bloom of Dinophysis acuminata produced, in autumn of 2005, a closure of the scallop harvesting in Bahía Inglesa, in the Chilean III region. Isolated cells of this Dinophysis species were shown to contain 180 pg cell(-1) of pectenotoxin 2 but neither okadaic acid nor any of its analogs or derivatives (at least at a detectable level). Examination of plankton and filter-feeder samples covering an area of ca. 350 km, from the location where the toxicity was recorded to Bahía Tongoy, showed that the unique toxin profile found in the first bloom was widespread over that part of Chile and persisted for months. The analysis were carried out by HPLC-ESI-MS using positive ionization mode, with a detection limit below 2 ng of OA mL(-1) of methanolic extract. This is the first report of the presence of pectenotoxins in the plankton of the Pacific coast of America and in the studied filter feeders. This is also the first report of a Dinophysis species containing pectenotoxins and not any toxin of the okadaic acid group.


Subject(s)
Dinoflagellida/chemistry , Environmental Monitoring/statistics & numerical data , Furans/analysis , Invertebrates/chemistry , Marine Toxins/analysis , Phytoplankton/chemistry , Pyrans/analysis , Animals , Chile , Chromatography, High Pressure Liquid , Furans/chemistry , Macrolides , Marine Toxins/chemistry , Mass Spectrometry , Molecular Structure , Pyrans/chemistry
18.
Medicina (Bogotá) ; (41): 20-21, out. 1995.
Article in Spanish | LILACS | ID: lil-307199

ABSTRACT

El fenómeno de la violencia contra la niñez, contra la juventud, contra las mujeres, es un fenómeno que tiene dos características: es fundamentalmente urbano, en tanto que el fenómeno poítico de la violencia es fundamentalmente rural, no se pueden entonces abocar con la misma perspectiva. En Bogotá se ha registrado en los últimos años un crecimiento impresionante en cuando a violencia. El sector de la salud es el que con más facilidad está sufriendo las consecuencias. En el caso del homicidio, por ejemplo, entre 1983 y 1992 se cuadriplicó el número de casos en esta ciudad, de acuerdo con informe de la Fiscalía. En Medicina Legal se reportaron 8.172 casos de muertes violentas, distribuídos por arma de fuego, accidentes de tránsito, armas cortopuntantes, quemaduras, caídas y contusiones, ahogamiento, intoxicación, estrangulamiento, electrocución, etc


Subject(s)
Child Abuse , Domestic Violence , Colombia
19.
In. Ascofame. II Reunion de Expertos y CXX Consejo Directivo de la Asociacion Colombiana de Facultades de Medicina. Bogota, Ascofame, 1990. p.24-42. (Rev. Nac. educ. med, 2, 1).
Monography in Spanish | LILACS | ID: lil-133902

Subject(s)
Health Policy , Legislation
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