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Ticks are involved in the transmission a plethora of pathogens. To effectively control ticks and mitigate the risks associated with tick-borne diseases, it is important to implement tick control measures. These may include the use of acaricides as well as the development and implementation of an alternative, environmentally friendly tick management program that include practices such as habitat modification or establishing biological control. Ixodiphagus hookeri Howard is a tick-specific parasitoid wasp that predates on several species of ixodid ticks and could contribute to the control of the tick population. This work aimed to detect the presence of parasitoid wasps in ticks (Ixodidae) using genetic approaches. Several tick species of the genera Ixodes, Haemaphysalis, and Dermacentor, with a sympatric occurrence in the Slovak Karst National Park in southeastern Slovakia, were screened for the presence of wasps of the genus Ixodiphagus. The DNA of the parasitoids was detected in four tick species from three genera. This work presents the first molecular detection of parasitoids in two Dermacentor tick species, as well as the first molecular identification of Ixodiphagus wasps in Ixodes ricinus and Haemaphysalis concinna ticks from the Karst area. In the given area, it was observed that I. ricinus and H. concinna ticks are hyper-parasitized by wasps. Moreover, it was observed that wasps here can parasitize several tick species, some of which are of less significance for human and animal health (as they transmit fewer pathogens).
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Background: Remote ischemic postconditioning (RIPostC) may protect the brain from ischemia/reperfusion (I/R) injury. The association between RIPostC and obesity has not yet been extensively studied. Methods: Twelve-week-old male Zucker diabetic fatty (ZDF; n=68) and Zucker diabetic lean (ZDL; n=51) rats were subjected to focal cerebral ischemia for 90 minutes, followed by 24 hours of reperfusion. RIPostC was performed with 5-minute I/R cycles using a tourniquet on the right hind limb. Results: The results showed a negative association between obesity and neurological impairment in ischemic animals. We observed a 70% greater infarct size in ZDF rats compared with their lean counterparts, as evaluated by 2,3,5-triphenyltetrazolium chloride staining. To measure the total fragmented DNA in peripheral lymphocytes, comet assay was performed. Obese rats exhibited higher levels of DNA damage (by approximately 135%) in peripheral blood lymphocytes even before the induction of stroke. RIPostC did not attenuate oxidative stress in the blood in obese rats subjected to ischemia. Focal cerebral ischemia increased core and penumbra tissue glutamate release in the brain and decreased it in the blood of ischemic ZDL rats, and these changes improved following RIPostC treatment. However, changes in blood and tissue glutamate content were not detected in ischemic ZDF rats or after RIPostC intervention. Conclusion: Our findings suggest that obese animals respond more severely to ischemia-reperfusion brain injury. However, obese animals did not achieve neuroprotective benefits of RIPostC treatment.
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The successful implementation of remote ischaemic conditioning as a clinical neuroprotective strategy requires a thorough understanding of its basic principles, which can be modified for each patient. The mechanisms of glutamate homeostasis appear to be a key component. In the current study, we focused on the brain-to-blood glutamate shift mediated by glutamate transporters (excitatory amino acid transports [EAATs]) and the effect of remote ischaemic preconditioning (RIPC) as a mediator of ischaemic tolerance. We used model mimicking ischaemia-mediated excitotoxicity (intracerebroventricular administration of glutamate) to avoid the indirect effect of ischaemia-triggered mechanisms. We found quantitative changes in EAAT2 and EAAT3 and altered membrane trafficking of EAAT1 on the cells of the choroid plexus. These changes could underlie the beneficial effects of ischaemic tolerance. There was reduced oxidative stress and increased glutathione level after RIPC treatment. Moreover, we determined the stimulus-specific response on EAATs. While glutamate overdose stimulated EAAT2 and EAAT3 overexpression, RIPC induced membrane trafficking of EAAT1 and EAAT2 rather than a change in their expression. Taken together, mechanisms related to glutamate homeostasis, especially EAAT-mediated transport, represents a powerful tool of ischaemic tolerance and allow a certain amount of flexibility based on the stimulus used.
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Proteínas de Transporte de Glutamato en la Membrana Plasmática , Precondicionamiento Isquémico , Humanos , Proteínas de Transporte de Glutamato en la Membrana Plasmática/metabolismo , Ácido Glutámico/toxicidad , Ácido Glutámico/metabolismo , Transportador 2 de Aminoácidos Excitadores/metabolismo , Transportador 1 de Aminoácidos Excitadores/metabolismo , Transportador 3 de Aminoácidos Excitadores/metabolismo , Aminoácidos Excitadores , IsquemiaRESUMEN
Remote ischaemic conditioning (RIC) becomes an attractive strategy for the endogenous stimulation of mechanisms protecting neurons against ischaemia. Although the processes underlying the RIC are not clearly understood, the homeostasis of glutamate seems to play an important role. The present study is focused on the investigation of the brain to blood efflux of glutamate in a condition mimicking ischaemia-mediated excitotoxicity and remote ischaemic preconditioning (RIPC). The animals were pre-treated with a hind-limb tourniquet one hour before the intraventricular administration of glutamate and its release was monitored as the concentration of glutamate/glutathione in blood and liquor for up to 1 h. The transport mediated by excitatory amino acid transporters (EAATs) was verified by their inhibition with Evans Blue intraventricular co-administration. RIPC mediated the efflux of glutamate exceeding from CSF to blood in the very early stage of intoxication. As a consequence, the blood level of glutamate rose in a moment. EAATs inhibition confirmed the active role of glutamate transporters in this process. In the blood, elevated levels of glutamate served as a relevant source of antioxidant glutathione for circulating cells in RIPC-treated individuals. All of those RIPC-mediated recoveries in processes of glutamate homeostasis reflect the improvement of oxidative stress, suggesting glutamate-accelerated detoxication to be one of the key mechanisms of RIPC-mediated neuroprotection.
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Ácido Glutámico , Precondicionamiento Isquémico , Humanos , Animales , Encéfalo , Isquemia , GlutatiónRESUMEN
We have recently shown that the blood cell-derived secretome of remote ischaemic (RIC)-conditioned individuals provides an external source of neuroprotection. In this study, we identified the bioactive compounds from the total proteins released by those cells. Our main strategy was to separate protein-protein complexes while maintaining their native structure and testing their bioactive properties. Subsequently, we identified up- and downregulated bioactive proteins. We uncovered two bioactive fractions composed of 18 proteins. Most of the protein peaks were unchanged; however, RIC mediated a decrease in two peaks (comprising seven proteins) and an increase in one peak (identified as haptoglobin). When focussing on the biological activity of these proteins, we found positive impacts on the regulation of cellular metabolic processes and an increase in biological processes related to the acute phase response and inflammation in the RIC-treated samples. Although we have identified the 18 proteins that exert the greatest cytoprotection, additional studies are needed to elucidate their particular function and detailed mechanisms of action.
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Fármacos Neuroprotectores , Animales , Ratas , Fármacos Neuroprotectores/farmacología , Haptoglobinas , Secretoma , Neuroprotección , Células SanguíneasRESUMEN
Background: The aim of the study was to compare the continuous glucose monitoring (CGM)-determined glycaemic variability (GV) of pregnant women with gestational diabetes mellitus (GDM) and without GDM (CG; control group). The secondary aim was to evaluate the association between risk factors of diabetes in pregnancy and parameters of glyceamic control. Methods: Demographic, biometric and biochemical parameters were obtained for pregnant women (20-38 years old) who after an oral glucose tolerance test were examined by 7-day continuous glucose monitoring using a iPro®2 Professional CGM. Results: The differences in GV between women with GDM and CG compared by total area under glucose curve (total AUC, (mmol·day/L) was statistically significant (p = 0.006). Other parameters of glycaemic control such as mean glucose, standard deviation, coefficient of variation, J-index, % time-above target range 7.8 mmol/L (%TAR), % time-in range 3.5-7.8 mmol/L (%TIR), time-below target range 3.5 mmol/L (%TBR), glycated haemoglobin were not significantly different in the study groups. Risk factors (a family history of diabetes, pre-pregnancy BMI, higher weight gain and age) correlated with parameters of glycaemic control. Conclusions: We found a significant difference in GV of women with and without GDM by total AUC determined from CGM. TIR metrics were close to significance. Our work points at an increased GV in relation to the risk factors of GDM. Pregnant women with risk factors have higher probability of severe GV with its consequences on maternal and fetal health state.
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Diabetes Gestacional , Adulto , Glucemia , Automonitorización de la Glucosa Sanguínea , Diabetes Gestacional/epidemiología , Femenino , Humanos , Embarazo , Mujeres Embarazadas , Factores de Riesgo , Adulto JovenRESUMEN
Recently, the function of blood cells in remote ischemic conditioning (RIC) mediated neuroprotection was undoubtedly confirmed. In the present paper, we have focused on the role of blood elements in glutamate homeostasis. The blood of remote conditioned (tolerant) animals was incubated ex vivo with 100 µM glutamate, and the quantitative and qualitative changes of excitatory amino acid transporters (EAAT 1, 2, and 3) were determined. We confirmed RIC mediated accelerated sequestration of extracellular glutamate via EAATs and altered distribution of that amino acid between plasma and cell elements compared to non-tolerant counterparts. The activity of EAATs was elevated in erythrocytes and monocytes, while the density of transporters was not affected. Quantitative changes of EAAT1 density were detected solely in platelets where the forced scavenging was independent of EAATs inhibition. Surprisingly, the trafficking of immunovisualised EAAT2 and 3 raised at tolerant erythrocytes and monocytes. We have found that protein synthesis underlined this process. On the other hand, depletion of protein synthesis did not significantly affect the scavenging capacity of those cell populations. Our work has demonstrated that the elevated blood scavenging of glutamate overdose could be one of the potential mechanisms underlying RIC mediated tissue protection.
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Proteínas de Transporte de Glutamato en la Membrana Plasmática/sangre , Ácido Glutámico/sangre , Miembro Posterior/irrigación sanguínea , Miembro Posterior/metabolismo , Precondicionamiento Isquémico/métodos , Animales , Transporte Biológico/fisiología , Masculino , Ratas , Ratas Wistar , Factores de TiempoRESUMEN
Glutamate represents the main excitatory neurotransmitter in the mammalian brain; however, its excessive elevation in the extracellular space is cytotoxic and can result in neuronal death. The ischemia initiated brain damage reflects changes in glutamate concentration in peripheral blood. This paper investigated the role of the brain in blood efflux of the glutamate in an improved tolerance of the brain tissue to ischemic conditions. In the rat model of focal brain ischemia, the neuroprotection was initiated by rapid remote ischemic preconditioning (rRIPC). Our results confirmed a strong neuroprotective effect of rRIPC. We observed reduced infarction by about 78% related to improved neuronal survival by about 70% in the ischemic core. The level of tissue glutamate in core and penumbra dropped significantly and decreased to control value also in the core region of the contralateral hemisphere. Despite significant improvement of blood-brain barrier integrity (by about 76%), the additional gain of glutamate content in the peripheral blood was caused by rRIPC. Based on our results, we can assume that neuroprotection mediated by rapid remote ischemic preconditioning could lie in the regulated, whole-brain release of glutamate from nerve tissue to the blood, which preserves neurons from the exposure to glutamate toxicity and results in reduced infarction.
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Isquemia Encefálica/metabolismo , Ácido Glutámico/metabolismo , Animales , Encéfalo/fisiopatología , Isquemia Encefálica/fisiopatología , Muerte Celular/efectos de los fármacos , Ácido Glutámico/sangre , Ácido Glutámico/toxicidad , Precondicionamiento Isquémico/métodos , Masculino , Neuronas/efectos de los fármacos , Neuroprotección/efectos de los fármacos , Neuroprotección/fisiología , Fármacos Neuroprotectores/farmacología , Ratas , Ratas Sprague-DawleyRESUMEN
Retinoic acid (RA) is a biologically active form of vitamin A. Teratogenicity has been observed in pregnant mammals exposed to high doses of vitamin A. We investigated the distribution of nitrergic neurons in rat prefrontal cortex (PFC) at developmental stages 7 days to young adulthood under physiological conditions and after prenatal application of all trans-RA. The neurons were studied histochemically using NADPH-diaphorase, which stains neurons dark blue. We found that nitrergic neurons differentiate rapidly and reach structural maturity by the end of the second week of postnatal development. We found that the processes of the neurons of nitrergic neurons of 14-day-old rats in the RA group were shorter than those of the control group. Our findings suggest that excess RA during the prenatal period may influence the development and morphology of NADPH-diaphorase positive neurons, probably by RA-specific receptors in the PFC of 14-day-old rats. RA receptors may be the main effector molecules responsible for the changes of dendrite length induced by all-trans RA. During later development, changes are not observed, probably due to maturation of the nervous system.
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NADP/metabolismo , Neuronas/efectos de los fármacos , Corteza Prefrontal/citología , Tretinoina/farmacología , Animales , Neuronas/fisiología , Ratas , Ratas WistarRESUMEN
The indirect use of the protective potential of stem cells in the form of cell secretomes has become an attractive strategy in regenerative medicine. In the present work, we studied the paracrine activity of blood cells that could be modulated towards a neuroprotective nature using in vivo remote conditioning (i.e. tolerant blood cells). The increased neuronal survival mediated by the tolerant secretome was clearly confirmed in vitro in a model of glutamate toxicity in a primary culture of rat cortical neurons and in vivo in a pre- and post-treatment of rats that were subjected to transient occlusion of the middle cerebral artery. Bioinformatic-based analysis of the protein profile revealed higher amounts of proteins released by the tolerant blood cells; 29 proteins were recognised as secreted. More than half of these secreted proteins were involved in the biological processes of the response to the stimulus (GO:0050896) and the response to chemicals (GO:0042221). The protective phenotype was most likely mediated by the synergistic effect of multiple identified proteins, including unique to the tolerant secretome (ceruloplasmin, D-3-phosphoglycerate dehydrogenase) and was promoted by the co-participation of several reaction pathways. The most probably of these pathways were post-translation protein modification, MAP2K and MAPK activation and platelet activation. Taken together, our results demonstrate that properly stimulated blood cells could serve as a source for cell-free-based therapies of regenerative medicine.
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Células Sanguíneas/metabolismo , Isquemia Encefálica , Precondicionamiento Isquémico/métodos , Neuronas/efectos de los fármacos , Neuroprotección , Proteoma/farmacología , Animales , Encéfalo , Células Cultivadas , Masculino , Comunicación Paracrina/fisiología , Plasma/metabolismo , Proteoma/metabolismo , Ratas , Ratas WistarRESUMEN
Stroke induces widespread changes in the brain. In this paper, we monitored some markers of early (2â¯h) and delayed events (1, 3 and 7 days of reperfusion) initiated by middle cerebral artery occlusion in core/penumbra counterparts of the non-ischemic hemisphere (i.e. contra-core and contra-penumbra). Our results showed that a profound transient drop (2â¯h and 3 days) of protein synthesis was measured in the contra-core, while the contra-penumbra exhibited translation over-activity at the same time. Glutamate release was detected only in the contra-core, with a peak on the first day. Degenerating neurons became visible in the striatum (day 1), followed by cortex (day 3), earlier in contra-penumbra and later in contra-core. Moreover, the loss of NADPH diaphorase-positive neurons in the non-ischemic hemisphere was detected, with the greatest drop at the first day. Total microglia also started to fall, the earliest in the contra-penumbra region of the striatum (day 1), followed by the contra-core of the striatum and both cortex regions at the seventh day. In conclusion, transient focal ischemia affects remote regions of the brain and initiates processes involved in neuronal degeneration in an order which corresponds to the tissue sensitivity to ischemia, namely earlier in the contra-penumbra, and afterwards in the contra-core. The mechanism of secondary damage would influence the progressive neuronal loss of more distant brain regions.
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Isquemia Encefálica/patología , Lateralidad Funcional , Degeneración Nerviosa/patología , Animales , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas WistarRESUMEN
It has been shown that ischemia of remote organs can generate resistance to ischemic conditions within sensitive brain tissues. However, only limited information about its mechanism is available. In the present paper, we used hind-limb ischemia by tourniquet to generate early remote ischemic tolerance in rats. The main objective was to investigate the role of glutamate in the process of neuroprotection and discover parameters that are affected in the blood of ischemia-affected animals. Our results showed that pretreatment with a hind-limb tourniquet caused a decrease in neurodegeneration by about 30%. However, we did not observe neurological deficit recovery. When compared to ischemia, glutamate concentration decreased in all observed brain regions (cortex, CA1 and dentate gyrus of hippocampus), regardless of their sensitivity to blood restrictions. In contrast to this, the blood levels raised significantly from 26% to 29% during the first four days of postischemic reperfusion. Pretreatment of animals reduced systemic oxidative stress-as represented by lymphocytic DNA damage-by about 80%, while changes in blood antioxidant enzymes (catalase, superoxide dismutase) were not detected. With these data we can further hypothesize that hind-limb-tourniquet preconditioning could accelerate brain-to-blood efflux of glutamate which could positively impact neuronal survival of ischemia-affected brain regions. Moreover, remote preconditioning improved systemic oxidative stress and did not seem to be affected by enzymatic antioxidant defenses in the blood.
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Encéfalo/metabolismo , Ácido Glutámico/sangre , Precondicionamiento Isquémico , Estrés Oxidativo/fisiología , Animales , Isquemia/tratamiento farmacológico , Precondicionamiento Isquémico/métodos , Masculino , Neuroprotección/fisiología , Ratas Wistar , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Superóxido Dismutasa/metabolismoRESUMEN
The present survey aimed to investigate flea and tick fauna parasitizing Slovak red fox populations with special emphasis on canine pathogens they transmit. A total of 407 fleas and 105 ticks were collected from 90 red foxes from two geographically distant regions. Seven flea species (Chaetopsylla globiceps, Pulex irritans, Archaeopsylla erinacei, Chaetopsylla rothschildi, Chaetopsylla trichosa, Ctenocephalides canis, and Ctenopthalmus assimilis) and three species of hard ticks (Ixodes ricinus, Ixodes hexagonus, Haemaphysalis concinna) were recorded on sampled animals. Consequently, the DNA of five different pathogen taxa was confirmed in collected arthropod vectors: Bartonella spp. (in P. irritans, Ch. globiceps, and Ct. assimilis), Rickettsia spp. (in A. erinacei, I. ricinus, I. hexagonus, and H. concinna), Anaplasma phagocytophilum (in I. ricinus), Theileria sp. (in Ch. globiceps and H. concinna), and Hepatozoon canis (in I. ricinus and I. hexagonus). Mycoplasma spp., Dipylidium caninum, and Acanthocheilonema reconditum were not found in fleas or ticks in this study.
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Enfermedades de los Perros/epidemiología , Infestaciones por Pulgas/veterinaria , Zorros/parasitología , Ixodidae/microbiología , Siphonaptera/microbiología , Infestaciones por Garrapatas/microbiología , Animales , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/parasitología , Perros , Infestaciones por Pulgas/epidemiología , Ixodidae/parasitología , Siphonaptera/parasitología , Eslovaquia , Infestaciones por Garrapatas/parasitologíaRESUMEN
The incidence of tick-borne diseases caused by Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum and Rickettsia spp. has been rising in Europe in recent decades. Early pre-assessment of acarological hazard still represents a complex challenge. The aim of this study was to model Ixodes ricinus questing nymph density and its infection rate with B. burgdorferi s.l., A. phagocytophilum and Rickettsia spp. in five European countries (Italy, Germany, Czech Republic, Slovakia, Hungary) in various land cover types differing in use and anthropisation (agricultural, urban and natural) with climatic and environmental factors (Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Land Surface Temperature (LST) and precipitation). We show that the relative abundance of questing nymphs was significantly associated with climatic conditions, such as higher values of NDVI recorded in the sampling period, while no differences were observed among land use categories. However, the density of infected nymphs (DIN) also depended on the pathogen considered and land use. These results contribute to a better understanding of the variation in acarological hazard for Ixodes ricinus transmitted pathogens in Central Europe and provide the basis for more focused ecological studies aimed at assessing the effect of land use in different sites on tick-host pathogens interaction.
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Clima , Bacterias Gramnegativas/crecimiento & desarrollo , Ixodes/microbiología , Análisis Espacio-Temporal , Anaplasma phagocytophilum/crecimiento & desarrollo , Animales , Borrelia burgdorferi/crecimiento & desarrollo , Europa (Continente)/epidemiología , Ninfa , Rickettsia/crecimiento & desarrolloRESUMEN
Ischemic tolerance (IT) has gained attention as an attractive strategy for improving stroke outcome. Recently, it was shown that signal responsible for rapid IT induction (tolerance induction factor - TIF) is transmitted via circulating blood. In this study, we have hypothesized about the role of the blood cell compartment in TIF production. We used hind-limb ischemia to generate TIF as a rapid preconditioning against transient middle cerebral artery occlusion (MCAO). The essential properties of protein synthesis inhibitors actinomycin D and cycloheximide were utilized to obtain the following results: (i) TIF is proteinaceous. Hind-limb ischemia mediates gene expression followed by translation, resulting in the production of TIF. Blocking of each of these two steps in protein synthesis resulted in rapid infarct evolution (281.5 ± 23.37 and 330.4 ± 71.8 mm3 , respectively). (ii) Tourniquet-treated muscle is not a source of TIF. Actinomicine D injected into rat prior to tolerance induction significantly suppressed RNA synthesis in blood cells and muscle tissue. Cross-circulation of those rats (donors) with control animals (recipients) did not mediate significant infarct reduction (272.9 ± 12.45 mm3 ), even when hind-limb ischemia was performed before MCAO in the recipient (223.2 ± 37.51 mm3 ). (iii) Blood cells serve as a source of TIF. Preischemic transfusion of plasma-free, protein-synthesis-inactive blood cells, which were obtained from tolerant animals did not reduce infarct volume in recipients (131 ± 16.1 mm3 ) in a range comparable with their protein-synthesis-active counterparts (17.2 ± 12 mm3 ). We can conclude that blood cells are associated with the induction of rapid IT via production of a bioactive proteinaceous substance.
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Células Sanguíneas/metabolismo , Infarto de la Arteria Cerebral Media/sangre , Precondicionamiento Isquémico/métodos , Animales , Células Sanguíneas/efectos de los fármacos , Encéfalo/irrigación sanguínea , Cicloheximida/farmacología , Dactinomicina/farmacología , Infarto de la Arteria Cerebral Media/terapia , Masculino , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Inhibidores de la Síntesis de la Proteína/farmacología , Ratas , Ratas WistarRESUMEN
We investigated the diversity of Bartonella in Apodemus agrarius, an important rodent of peri-domestic habitats, which has spread into Europe in the past 1000 years. Spleen samples of 344 A. agrarius from Eastern Slovakia were screened for the presence of Bartonella spp. using 16S-23S rRNA internal transcribed spacer region and bacteria were detected in 9% of rodents. Based on sequencing of three housekeeping genes (gltA, rpoB and groEL) Bartonella genotypes were ascribed to the species typical for mice and voles: B. grahamii, B. taylorii and B. birtlesii. However, the study also confirmed presence of genotypes belonging to the B. clarridgeiae/B. rochalimae clade, and the B. elizabethae/B. tribocorum clade, which are not commonly found in woodland rodents. In addition, a potential recombination event between these two genotypes was noted, which highlights an important role of A. agrarius in shaping Bartonella diversity and evolution.
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Infecciones por Bartonella/veterinaria , Bartonella/genética , Variación Genética , Genotipo , Murinae/microbiología , Animales , Bartonella/clasificación , Bartonella/aislamiento & purificación , Infecciones por Bartonella/epidemiología , Infecciones por Bartonella/microbiología , ADN Espaciador Ribosómico/genética , Europa (Continente)/epidemiología , Evolución Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Enfermedades de los Roedores/microbiología , EslovaquiaRESUMEN
Many rickettsiae of the spotted fever group are emerging pathogens causing serious diseases associated with vertebrate hosts. Ixodidae ticks are known as their vectors. Investigation of the relative abundance of questing Ixodes ricinus and their infection with Rickettsia spp. in an agricultural site comprising a game reserve in Slovakia was the aim of this study. In total, 2198 I. ricinus (492 larvae, 1503 nymphs and 203 adults) were collected by flagging the vegetation along 100 m(2) transects in Rozhanovce (eastern Slovakia): 334, 595 and 1269 in 2011, 2012 and 2013, respectively. Considering questing nymphs and adults, the highest relative density of 81 individuals/100 m(2) was observed in May 2013, the lowest of 0.3 individuals/100 m(2) in March 2012. A total of 1056 ticks (853 nymphs, 100 females and 103 males; 2011: n = 329, 2012: n = 509 and 2013: n = 218) were individually screened by PCR-based methods for the presence of Rickettsia spp. The overall prevalences were 7.3% for nymphs, 15% for females, 7.8% for males; 7.0% in 2011, 8.4% in 2012, and 8.7% in 2013. The maximum prevalences were observed in July in nymphs and in May in adults. Sequencing showed infection with R. helvetica in 73 ticks (72.6% nymphs, 16.4% females, 11% males) and with R. monacensis in 11 ticks (8 nymphs, 3 females). The results showed the circulation of pathogenic Rickettsia species in the agricultural site and a potential risk for humans to encounter infected ticks.
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Ixodes/microbiología , Rickettsia/aislamiento & purificación , Estaciones del Año , Agricultura , Animales , Femenino , Masculino , EslovaquiaRESUMEN
Rodents are important reservoir hosts of many tick-borne pathogens. Their importance in the circulation of the emerging bacterial agent, Candidatus Neoehrlichia mikurensis and the intraerythrocytic protozoan parasite, Babesia microti has been recently proposed. The aim of the present study was to identify the presence and genetic diversity of Candidatus N. mikurensis and B. microti circulating in the natural foci among rodents and two species of ixodid ticks (Ixodes ricinus and Ixodes trianguliceps). In 2011-2013, rodents were captured at sampling sites in Eastern Slovakia. A total of 997 rodents (324 Apodemus agrarius, 350 Apodemus flavicollis, 271 Myodes glareolus, and 52 other rodent species), 788 feeding ticks from rodents, and 1375 questing ticks were investigated for the presence of pathogens by molecular methods followed by DNA sequencing. Candidatus N. mikurensis was detected in 2.4% of questing I. ricinus nymphs and 2.6% of questing adult I. ricinus ticks, spleens of rodents (1.6%), as well as in feeding larval I. ricinus (0.3%) and feeding larval I. trianguliceps ticks (3.3%). The 16S rRNA and gltA gene sequences of Candidatus N. mikurensis obtained in this study confirmed a high degree of genetic identity of this bacterium in Europe. DNA of B. microti was found in ear (0.6%) and spleen biopsies of rodents (1.9%), in rodent foetus (3.8%) and feeding larval (5.2%) and nymphal (8.7%) I. ricinus, in questing nymphal I. ricinus (0.5%) and questing adult I. ricinus ticks (0.3%). None of the 112 I. trianguliceps ticks were infected. B. microti was represented by two different genotypes: 92% of the positive samples belonged to the zoonotic type strain from Jena (Germany). The results of this study underline the importance of rodents in the circulation of both emerging pathogens in natural foci.
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Infecciones por Anaplasmataceae/microbiología , Anaplasmataceae/genética , Vectores Arácnidos , Babesia microti/genética , Babesiosis/parasitología , Ixodes , Anaplasmataceae/aislamiento & purificación , Infecciones por Anaplasmataceae/epidemiología , Animales , Vectores Arácnidos/microbiología , Vectores Arácnidos/parasitología , Arvicolinae , Babesia microti/aislamiento & purificación , Babesiosis/epidemiología , Reservorios de Enfermedades , Femenino , Variación Genética , Ixodes/microbiología , Ixodes/parasitología , Masculino , Murinae , Ninfa , ARN Ribosómico 16S/genética , Roedores , Análisis de Secuencia de ADN , Eslovaquia/epidemiologíaRESUMEN
The impact of therapeutic intervention in stroke depends on its appropriate timing during infarct evolution. We have studied markers of brain tissue damage initiated by permanent occlusion of the middle cerebral artery (MCAO) at three time points during which the infarct spread (1, 3 and 6 h). Based on Evans Blue extravasation and immunohistochemical detection of neurons, we confirmed continuous disruption of blood-brain barrier and loss of neurons in the ischaemic hemisphere that peaked at the sixth hour, especially in the core. Glutamate content started to rise dramatically in the entire hemisphere during the first 3 h; the highest level was determined in the core 6 h after MCAO (141 % increase). Moreover, the enzyme antioxidant defence grew by about 42 % since the first hour in the ipsilateral penumbra. Enzymes of the apoptotic pathway as well as mitochondrial enzyme release were detected since the third hour of MCAO in the ischaemic hemisphere; all achieved their maxima in the penumbra during both time periods (except cytochrome C). In conclusion, the preserved integrity of mitochondrial membrane and incompletely developed process of apoptosis may contribute to the better therapeutic outcome after ischaemic attack; however, a whole brain response should not be omitted.
Asunto(s)
Infarto de la Arteria Cerebral Media/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Permeabilidad Capilar , Ácido Glutámico/metabolismo , Infarto de la Arteria Cerebral Media/patología , Masculino , Ratas , Ratas WistarRESUMEN
Rodents are important reservoir hosts of tick-borne pathogens. Anaplasma phagocytophilum is the causative agent of granulocytic anaplasmosis of both medical and veterinary importance. In Europe, this pathogen is primarily transmitted by the Ixodes ricinus tick among a wide range of vertebrate hosts. However, to what degree A. phagocytophilum exhibits host specificity and vector association is poorly understood. To assess the extent of vector association of this pathogen and to clarify its ecology in Central Europe we have analyzed and compared the genetic variability of A. phagocytophilum strains from questing and feeding I. ricinus and Ixodes trianguliceps ticks, as well as from rodent' tissue samples. Tick collection and rodent trapping were performed during a 2-year study (2011-2012) in ecologically contrasting setting at four sites in Eastern Slovakia. Genetic variability of this pathogen was studied from the collected samples by DNA amplification and sequencing of four loci followed by Bayesian phylogenetic analyses. A. phagocytophilum was detected in questing I. ricinus ticks (0.7%) from all studied sites and in host feeding I. trianguliceps ticks (15.2%), as well as in rodent biopsies (ear - 1.6%, spleen - 2.2%), whereas A. phagocytophilum was not detected in rodents from those sites where I. trianguliceps ticks were absent. Moreover, Bayesian phylogenetic analyses have shown the presence of two distinct clades, and tree topologies were concordant for all four investigated loci. Importantly, the first clade contained A. phagocytophilum genotypes from questing I. ricinus and feeding I. ricinus from a broad array of hosts (i.e.,: humans, ungulates, birds and dogs). The second clade comprised solely genotypes found in rodents and feeding I. trianguliceps. In this study we have confirmed that A. phagocytophilum strains display specific host and vector associations also in Central Europe similarly to A. phagocytophilum' molecular ecology in United Kingdom. This study suggests that A. phagocytophilum genotypes associated with rodents are probably transmitted solely by I. trianguliceps ticks, thus implying that rodent-associated A. phagocytophilum strains may not pose a risk for humans.