Alena Žákovská

Serological Confirmation of Borrelia burgdorferi Infection in Dogs in the Czech Republic

From the epidemiological point of view, dogs are very important since they are considered a suitable indicator of the spread of human borreliosis. Serum samples obtained from healthy, asymptomatic military dogs from 12 different areas in the Czech Republic were examined for IgG antibodies to Borrelia burgdorferi sensu lato (s.l.). The total of 399 serum samples were tested by a whole-cell ELISA. Specific antibodies to Borrelia burgdorferi s.l. were detected in 26 cases (6.5%). In different localities, the seroprevalence varied from 0.0% to 28.6%. Two local isolated strains Br-75 (Borrelia afzelii) and Br-97 (Borrelia garinii) were used as antigens. A total of 22 (5.5%) were positive for antibodies to Borrelia afzelii and 19 (4.8%) were positive for antibodies to Borrelia garinii. Fifteen cases were positive for both antibodies. A significantly higher seroprevalence was found in younger dogs (1–3 years) than in older ones (p < 0.05). An analysis of seroprevalence by months of sampling showed no significant difference (p > 0.05).

The prevalence of exercise-associated hyponatremia in 24-hour ultra-mountain bikers, 24-hour ultra-runners and multi-stage ultra-mountain bikers in the Czech Republic

BackgroundTo assess the prevalence of exercise-associated hyponatremia (EAH) in two 24-hour mountain bike (MTB) (R1,R2), one 24-hour running (R3) and one multi-stage MTB (R4) races held in the Czech Republic in a cluster of four cross-sectional studies.MethodsIn 27 ultra-mountain bikers (ultra-MTBers), 12 ultra-runners, and 14 multi-stage MTBers, fluid intake, changes (Δ) in body mass, hematocrit, plasma volume, plasma [Na+], plasma [K+], plasma osmolality, urine [Na+], urine [K+], urine specific gravity, urine osmolality, K+/Na+ ratio in urine, transtubular potassium gradient and glomerular filtration rate were measured and calculated. The use of non-steroidal anti-inflammatory drugs and symptoms of EAH were recorded using post-race questionnaires.ResultsOf the 53 finishers, three (5.7%) developed post-race EAH, thereof one (3.7%) ultra-MTBer, one (8.3%) ultra-runner and one (7.1%) multi-stage MTBer. Plasma [Na+] decreased significantly (p < 0.001) only in R4. Urine osmolality (R1, R3, R4 p < 0.001; R2 p < 0.05) and glomerular filtration rate (p < 0.001) increased, and body mass decreased in all races (p < 0.05). Δ body mass was inversely related to the number of kilometers achieved (p < 0.001) in R2 where better ultra-MTBers tended to lose more weight. Δ body mass (p < 0.001) and %Δ body mass (p = 0.05) were positively related to lower post-race plasma [Na+] in R3 that was associated with increased loss in body mass. Fluid intake was positively related to race performance in R1 and R2 (R1: p = 0.04; R2: p = 0.01) where ultra-MTBers in R1 and R2 who drank more finished ahead of those who drank less. Post-race plasma [Na+] was negatively associated with race performance in ultra-MTBers in R2 (p < 0.05), similarly ultra-runners in R3 (p < 0.05) where finishers with more kilometres had lower post-race plasma [Na+].ConclusionsThe prevalence of EAH in the Czech Republic was no higher compared to existing reports on ultra-endurance athletes in other countries. Lower plasma [Na+] and development of EAH may be attributed to overdrinking, a pituitary secretion of vasopressin, an impaired mobilization of osmotically inactive sodium stores, and/or an inappropriate inactivation of osmotically active sodium.

Changes in foot volume, body composition, and hydration status in male and female 24-hour ultra-mountain bikers

BackgroundThe effects of running and cycling on changes in hydration status and body composition during a 24-hour race have been described previously, but data for 24-hour ultra-mountain bikers are missing. The present study investigated changes in foot volume, body composition, and hydration status in male and female 24-hour ultra-mountain bikers.MethodsWe compared in 49 (37 men and 12 women) 24-hour ultra-mountain bikers (ultra-MTBers) changes (Δ) in body mass (BM). Fat mass (FM), percent body fat (%BF) and skeletal muscle mass (SM) were estimated using anthropometric methods. Changes in total body water (TBW), extracellular fluid (ECF) and intracellular fluid (ICF) were determined using bioelectrical impedance and changes in foot volume using plethysmography. Haematocrit, plasma [Na+], plasma urea, plasma osmolality, urine urea, urine specific gravity and urine osmolality were measured in a subgroup of 25 ultra-MTBers (16 men and 9 women).ResultsIn male 24-hour ultra-MTBers, BM (P < 0.001), FM (P < 0.001), %BF (P < 0.001) and ECF (P < 0.05) decreased whereas SM and TBW did not change (P > 0.05). A significant correlation was found between post-race BM and post-race FM (r = 0.63, P < 0.001). In female ultra-MTBers, BM (P < 0.05), %BF (P < 0.05) and FM (P < 0.001) decreased, whereas SM, ECF and TBW remained stable (P > 0.05). Absolute ranking in the race was related to Δ%BM (P < 0.001) and Δ%FM in men (P < 0.001) and to Δ%BM (P < 0.05) in women. In male ultra-MTBers, increased post-race plasma urea (P < 0.001) was negatively related to absolute ranking in the race, Δ%BM, post-race FM and Δ%ECF (P < 0.05). Foot volume remained stable in both sexes (P > 0.05).ConclusionsMale and female 24-hour ultra-MTBers experienced a significant loss in BM and FM, whereas SM remained stable. Body weight changes and increases in plasma urea do not reflect a change in body hydration status. No oedema of the lower limbs occurred.

CTRP1: A Molecular Link between Obesity and Hypertension

Background: CTRP1, a recently identified adipokine, was found to stimulate aldosterone production. Serum CTRP1 and plasma Aldosterone levels were significantly increased in patients with diabetes mellitus and metabolic syndrome. Therefore, it would be interesting to investigate whether the secretion of CTRP1 in human serum is associated with hypertension as well as with diabetes mellitus. Aim: This study evaluated serum CTRP1 and aldosterone concentrations in healthy individuals and in patients with diabetic nephropathy. Methods: Serum samples from 32 healthy individuals and 44 patients with diabetic nephropathy were measured for CTRP1, Aldosterone, diabetes-related biomarkers and renal disease-related biomarkers by enzyme-linked immunosorbent assay (ELISA). Results: Correlation analyses showed that serum CTRP1 in healthy individuals was not correlated with any other biochemical parameters or laboratory characteristic; however, in patients with diabetic nephropathy, a significant correlation was found between serum CTRP1 and Aldosterone (P=0.003), Urea, Cystatin C and ANGPTL4. Aldosterone level was significantly higher in subjects with diabetic nephropathy compared to healthy subjects (P=0.01). Discussion: Our results demonstrated that the adipokine CTRP1 is significantly associated with Aldosterone and support the hypothesis that CTRP1 may be a newly identified molecular link between obesity and hypertension.

Influence of environmental factors on the occurrence of Ixodes ricinus ticks in the urban locality of Brno–Pisárky, Czech Republic

ABSTRACT The occurrence of Ixodes ricinus ticks was observed in the suburban locality of Brno–Pisárky (South Moravia, Czech Republic) from March to November, 1996 to 2002. A total of 2,813 ticks was collected. Statistical tests divided the activity of ticks into three periods during the year. The curve of seasonality had two peaks with a maximum in May and August, with a significantly larger number of specimens collected during this period compared to other months. The abundance of ticks during Spring and Autumn months was comparable. All developmental stadia of ticks were found in this locality. The number of larvae, males, and females was not significantly different, but the occurrence of nymphs was significantly greater. Except for the year 2000, there were no statistically significant differences in tick abundance. Tick activity was not dependent on humidity but did vary directly with temperature. This relation had a linear character and could be described by the equation y = 8.3 + 1.8x.

The effect of a 100 km ultra-marathon under freezing conditions on selected immunological and haematological parameters

Although moderate exercise is beneficial for the human body and its immune system, exhaustive ultra-endurance performance in cold conditions might be harmful. The aim of this study was to examine the effect of a 100-km ultra-marathon under cold conditions (temperatures from −1°C to +1°C) on selected immunological, biochemical and hematological parameters. Participants were 15 runners (12 men and three women, age 40.3 ± 9.7 years, body mass 67.3 ± 9.0 kg and body height 1.74 ± 0.10 m, mean ± standard deviation). Leukocytes increased (p < 0.01) and, particularly, the number of leucocytes doubled in seven out of 15 athletes. Immature neutrophils, mature neutrophils and monocytes increased (p < 0.02), whereas lymphocytes and eosinophils did not change. IgG increased (p < 0.02), but IgA and IgM remained unchanged. Platelets increased (p < 0.01), whereas red blood cells, hematocrit and hemoglobin did not change. lactate dehydrogenase (LDH) and creatine kinase (CK) increased (p < 0.01), but alanine aminotransferase (ALT) did not change. There was an association between the markers of the acute inflammation of the organism (i.e., neutrophils, immature neutrophils, platelets, and monocytes) and the markers of muscle damage (i.e., CK, platelets, and LDH). There were no relationships among all the markers in relation to upper respiratory tract infections and liver damage. The highest change was noted in the increase of the number of immature neutrophils (1,019.2%) and CK levels (1,077.6%). In summary, this is the first study investigating immunological, hematological and biochemical parameters and showing that running a 100-km ultra-marathon under cold conditions leads to changes in several immunological, biochemical and hematological parameters indicating a severe stress on the body associated with increasing susceptibility to the development of infections.

Toxoplasma gondii and Neospora caninum in wild small mammals: Seroprevalence, DNA detection and genotyping.

Generally, rodents and other small mammals are considered as one of the sources of Toxoplasma gondii or Neospora caninum infection for cats and dogs as the definitive hosts of these two parasites, respectively. The aim of the study was to find out the prevalence of these two parasites in wild small mammals from the Czech Republic and to characterize T. gondii isolates by methods of molecular biology. A total of 621 wild small mammals were caught in the Czech Republic during years 2002-2014. Antibodies to T. gondii were detected by latex agglutination test in six (2.5%) of 240 small mammals (in two A. agrarius and four A. flavicollis). Antibodies to N. caninum were detected by commercially available competitive-inhibition enzyme-linked immunosorbent assay in one A. flavicolis (0.4%). Three of 427 (0.7%) liver samples were positive for T. gondii by PCR while negative for N. caninum. All embryo samples (n=102) were negative for both T. gondii and N. caninum. The three liver samples positive for T. gondii DNA (two from A. flavicollis and one from A. sylvaticus) were genotyped by 15 microsatellite markers and characterized as type II. To our knowledge, this is the first information about genetic characterization of T. gondii isolates in small mammals from Europe and the first detection of N. caninum antibodies in wild rodents from the Czech Republic.

Activity of the Tick Ixodes ricinus Monitored in a Suburban Park in Brno, Czech Republic, in Association with the Evaluation of Selected Repellents

ABSTRACT: The ever-increasing number of Lyme borreliosis patients led us to consider more effective procedures for disease prevention. The aim of our study was to monitor the annual activity and infectivity of Ixodes ricinus ticks in the Pisárky region, City of Brno, CR, and to test the responses of the locally-captured ticks to selected repellents. The result of regular one-hourper-week monitoring in 2011 was the collection of ticks that directly reflected the highest number of Lyme disease patients (4,835) detected throughout the period of recording in the Czech Republic. The ticks were examined for spirochaetes by dark field microscopy. The positive samples were identified by PCR analysis, confirming that 76% of these were infected with Borrelia burgdorferi sensu lato. Ticks were most abundant in May and June, with August having the highest risk for spirochaetal infection. Tick activity was statistically correlated with temperature. The moving-object-bioassay was used to study repellent efficiency on the Ixodes ricinus nymphs captured in the above-mentioned suburban park. Five selected commercial repellents based on DEET (N, N-diethyl-3-methylbenzamide) showed statistically different effects on the non-repellent control group.

Identification and characterization of 31 isolates of Borrelia burgdorferi (Spirochaetales, Spirochaetaceae) obtained from various hosts and vectors using PCR-RFLP and SDS-PAGE analysis

Borrelia burgdorferi sensu lato, the etiologic agent of Lyme borreliosis, circulates between ticks and vertebrate hosts. Two main genospecies typically occur in the Czech Republic Borrelia garinii and Borrelia afzelii, transmitted generally by Ixodes ricinus (L., 1758) ticks. The aim of our study was to identify spirochaete isolates focusing on Borrelia burgdorferi acquired from different sources: vectors (ticks), potential vectors (mosquitoes, small mites) and hosts (wild rodents). In the years 1996–2001 a total of 2398 ticks, 72 mites (from wild rodents), 2700 mosquito adults, 1798 mosquito larvae and organ parts (kidney and spleen) of 216 wild rodents were collected from seven localities in the Czech Republic. A total of 31 spirochaete strains were isolated: 13 strains from ticks, 1 strain from mite (Haemogamasus sp.), 15 strains from rodents, 1 strain from mosquito adults and 1 strain from mosquito larva. For the genospecies identification of these isolates PCR, PCR-RFLP was used and their characterization was also performed by SDS-PAGE. By nested PCR method all except one isolated strains were detected as Borrelia burgdorferi s.l. Following PCR-RFLP molecular analysis results, tick isolates were identified as B. garinii and B. afzelii, the strain isolated from the mite was identified as B. afzelii. This is the first isolated strain of B.b.s.l. from a different mite of infraorder Parasitiformes than tick. All of rodent isolates were identified as B. afzelii; mosquito adult isolate was identified as B. afzelii. Larval isolate from mosquito is spirochaete, but does not belong to Borrelia burgdorferi sensu lato group.

The occurrence of Borrelia burgdorferi sensu lato in certain ectoparasites (Mesostigmata, Siphonaptera) of Apodemus flavicollis and Myodes glareolus in chosen localities in the Czech Republic

Ticks represent the primary vectors of several serious diseases, including the Lyme disease caused by Borrelia burgdorferi sensu lato (Bbsl). In this study two dominant ectoparasitic groups of arthropods (Mesostigmata, Siphonaptera) were investigated for the presence of borrelian DNA in order to determine their potential role of vectors (or carriers) of this bacterium. All individuals (235) were collected from wild-living rodents obtained in three localities in the Czech Republic (Bažantula, Baba and Křižovice). The majority of parasites were members of the families Parasitidae and Dermanyssidae (Mesostigmata) and families Hystrichopsyllidae and Ceratophyllidae (Siphonaptera). The rodent host species was almost exclusively the yellow-necked mouse (Apodemus flavicollis). Bbsl was detected by the PCR method in the following ectoparasite species: Euryparasitus emarginatus (1), Eulaelaps stabularis (1), Haemogamassus nidi (1), Laelaps agilis (5), Myonyssus gigas (1) (Mesostigmata) and Ctenophthalmus agyrtes (1), C. solutus (3) (Siphonaptera).