The role of C-reactive protein:albumin ratio and Neutrophil:lymphocyte ratio in predicting coronary artery disease.

INTRODUCTION: Acute coronary syndrome (ACS), one of the most common causes of death worldwide, is a condition characterised by ischaemia and/or infarction due to reduced coronary blood flow. The most prevalent cause of ACS is coronary artery disease. In this study, we aimed to investigate the relationship between blood parameters that we commonly use in the laboratory [C-reactive protein (CRP), albumin, neutrophils and lymphocytes] and coronary artery disease (CAD). METHODS: This retrospective, single-centre study included 100 patients who underwent coronary angiography, with the diagnosis of acute coronary syndrome between January and June 2023, and 106 patients with high clinical suspicion and normal coronary arteries as a control group. The NLR was obtained from the ratio of neutrophils to lymphocytes and the CAR was obtained from the ratio of CRP to albumin. We analysed the relationship between CAD and NLR and CAR according to laboratory findings and demographic characteristics of the patients. RESULTS: The average age of the study group was 59 ± 10 years. NLR and CAR values were higher in the patient group than the control group (5.2 ± 3.3 vs 2.27 ± 1.2, p = 0.004 and 0.5 ± 0.1 vs 0.097 ± 0.095, respectively, p < 0.001). Albumin ratios were found to be statistically significantly lower in the patient group than the patient group (42.4 ± 4 vs 44 ± 3.3, respectively, p = 0.01). In addition, CAR and NLR showed a significant diagnostic value for CAD in receiver operating characteristic curve analysis (area under the curve: 0.68 ± 0.07, p = 0.003; 0.66 ± 0.09 p ≤ 0.001). CONCLUSIONS: NLR and CAR values, which are important indicators of inflammation, were found to be higher in the patient group. We believe it may be important to monitor these patients more frequently and follow them closely in terms of CAD, especially if the rate is higher in individuals without CAD who come for out-patient clinic check-ups.

Phylogenetic Analysis of Brucella melitensis Strains Isolated from Humans Using 16S rRNA Sequencing and Multiple Locus Variable Number of Tandem Repeats Analysis-16.

Background: Brucellosis is the most important public health problem worldwide, and the annual incidence of the disease in humans is 2.1 million. The Brucella genome is highly conserved, with over 90% similarity among species. The aim of this study was to perform species-level identification of Brucella spp. strains isolated from humans diagnosed with brucellosis and to further investigate the phylogenetic relationships using multiple locus variable number of tandem repeats analysis (MLVA)-16 and 16S rRNA sequencing analysis. Materials and Methods: Brucella spp. was isolated from the blood cultures of 54 patients who tested positive for brucellosis through serological examinations. Real-time PCR was used to identify the isolates in species, and the genus level of Brucella was confirmed with 16S rRNA. All isolates were subjected to phylogenetic analysis using variable number of tandem repeat analysis with multiple loci. Results: Subsequent analysis via real-time PCR confirmed these isolates to be of the Brucella melitensis species. The 16S rRNA sequence analysis showed 100% homogeneity among the isolates. MLVA revealed the formation of five different genotypic groups. While two groups were formed based on the 16S rRNA sequence analysis, five groups were formed in the MLVA. Conclusions: The study concluded that 16S rRNA sequence analysis alone did not provide sufficient discrimination for phylogenetic analysis but served as a supportive method for identification. MLVA exhibited higher phylogenetic power. The widespread isolation of B. melitensis from human brucellosis cases highlights the importance of controlling brucellosis in small ruminants to prevent human infections.

Evaluation of Pulmonary Function Tests, Dyspnea Scores, and Antibody Levels at the Six-Month Follow-Up of Patients Hospitalized for COVID-19 Pneumonia.

BACKGROUND: Coronavirus disease 2019 (COVID-19) causes various signs and symptoms, especially lung involvement, during acute infection and in the long term. In this study, we evaluated the follow-up results of patients with chronic COVID-19 over a 24-week period. METHODS: The study included a total of 100 post-COVID-19 patients (confirmed by real-time polymerase chain reaction (PCR) of a nasopharyngeal swab) who presented to the post-COVID-19 outpatient clinic with chronic COVID-19 symptoms 12 weeks after diagnosis, between April and June 2021. All of the patients in the study had a history of hospitalization and were grouped based on the severity of the acute COVID-19 infection (moderate: group 1, severe: group 2). RESULTS: A comparison of pulmonary function test parameters at week 12 showed that forced expiratory volume (FEV1)%, forced vital capacity (FVC)%, diffusing capacity of the lungs for carbon monoxide (DLCO)%, and DLCO divided by the alveolar volume (DLCO/VA)% values were significantly lower in group 2 than in group 1 (p<0.001 for all). At week 24, only DLCO and DLCO/VA values were lower (<0.001 for both). The mean modified Medical Research Council (mMRC) dyspnea scores of groups 1 and 2 were 1.4 ± 0.9 and 2.8 ± 1.1 at 12 weeks and improved to 0.9 ± 0.6 and 1.6 ± 0.6 at 24 weeks, respectively. The groups' mMRC scores at 12 and 24 weeks differed significantly (p=0.001, p=0.02). There was no difference in levels of IgM and IgG antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein between the groups at 12 or 24 weeks (p>0.05 for all). CONCLUSION: Improvement in pulmonary function parameters and mMRC scores may take longer than 24 weeks, especially in patients with severe COVID-19. Our results indicated that the levels of IgM and IgG neutralizing antibodies did not differ between patients with moderate and severe illness at 12 or 24 weeks.

Relationship between platelet/hemoglobin and radial thrombus in patients with coronary angiography via radial access.

Aim: To predict the development of radial artery thrombus (RAT) in patients with radial approach coronary angiography of platelet-to-hemoglobin ratio (PHR). Materials & methods: This study was designed to evaluate the relationship between RAT and PHR. A total of 1156 patients who had coronary angiography via the transradial approach between 2021 and 2022 in the authors' center were included in the study. Results: Radial thrombus was detected in 52 (4.5%) patients. PHR was higher in the group with thrombus and was statistically significant. In the regression model, PHR was an independent predictor of the development of radial thrombus (p = 0.007). Conclusion: High PHR may be an independent predictor of the development of radial thrombus.

Cardiac Parameters Better Predict ICU Admission and Short-Term Mortality in Hospitalized Patients With COVID-19.

Background COVID-19 is a multisystemic disease that affects many organs, and the use of some parameters is recommended both during hospitalization and follow-up. In this study, we investigated the relationship between blood (liver and kidney function tests, lactate, and D-dimer), infection (C-reactive protein (CRP), lymphocyte count, ferritin, and albumin), and cardiac (creatine kinase-myocardial band (CK-MB), troponin, and brain natriuretic peptide (BNP)) parameters with intensive care unit (ICU) admission and mortality. Materials and methods Patients hospitalized in Erzurum City Hospital with the diagnosis of COVID-19 between April 2020 and November 2022 were included in this retrospective study. The patient's files and electronic media records were retrospectively reviewed, and the patient's anamnesis, physical examination, clinical findings, biochemical parameters, and treatment methods were recorded. The ICU needs of the patients and the treatment processes in intensive care were found in the in-hospital records. The hospital records and six-month mortality data were obtained retrospectively with the necessary permissions. Thus, blood parameters and their relation to each other in terms of prognosis were evaluated in determining the six-month mortality rates of the patients and estimating the need for ICU. Results A total of 5100 patients were included in the study. The mean age of patients with mortality was 74.2 ± 11.2 and that without mortality was 59.9 ± 15.7 (p < 0.001). In the mortality (+) group, 61.5% of patients were male, and in the mortality (-) group, 47.4% of the patients were male (p < 0.001). The mean age of patients with ICU admission was 69.6 ± 13.6 and without ICU admission was 60.3 ± 15.9 years (p < 0.001). In the ICU admission (+) group, 60.5% of patients were male; and in the ICU admission (-) group, 47.2% of patients were male (p < 0.001). Death and ICU admission were observed more frequently in elderly and male patients (p < 0.001 for both mortality and ICU admission). Blood parameters were evaluated both in the mortality and ICU groups, and organ function tests, blood count parameters, inflammatory markers, and cardiac parameters were significantly associated with poor outcomes. Cox regression analysis showed that lactate, albumin, Ln(troponin), and Ln(BNP) were independent predictors of mortality and ICU admission. Receiver operating characteristics (ROC) curve analysis showed that Ln(troponin) and Ln(BNP) levels predicted the development of mortality and ICU admission better than other parameters. Discussion COVID-19 can cause problems in different systems as a result of an inflammatory response, secreted cytokines, hypercoagulability, and direct tissue damage. When treating patients, a more appropriate approach is to evaluate different parameters together rather than focusing on a single parameter and deciding accordingly. However, evaluating alterations in many parameters in a disease that affects many systems is difficult and increases the risk of mistakes. Although each blood parameter separately is important, it was observed that the cardiac parameters troponin I and BNP have better predictive values than others in predicting the course and prognosis of COVID-19. Conclusion Blood parameters are used in COVID-19 diagnosis, treatment, and follow-up. Although it is not primarily a cardiac disease, cardiac markers can provide better results in showing the course and prognosis of COVID-19.

Prevalence, Risk Factors, Prognosis, and Management of Pericardial Effusion in COVID-19.

Background: There is limited data in the literature about the clinical importance and prognosis of pericardial effusion (PE) in patients discharged after recovering from COVID-19, but large-scale studies have yet to be available. This study investigated the prevalence, risk factors, prognosis, late clinical outcomes, and management of PE in COVID-19. Materials and Methods: Between August 2020 and March 2021, 15,689 patients were followed up in our pandemic hospital due to COVID-19. Patients with positive polymerase chain reaction (PCR) test results and PE associated with COVID-19 in computed tomography (CT) were included in the study. The patients were divided into three groups according to PE size (mild, moderate, and large). Transthoracic echocardiography (TTE) records, laboratory data, clinical outcomes, and medical treatments of patients discharged from the hospital were retrospectively reviewed. Results: According to the PE size (mild, moderate, large) of 256 patients with PE at admission or discharge, the mean age was 62.17 ± 16.34, 69.12 ± 12.52, and 72.44 ± 15.26, respectively. The mean follow-up period of the patients was 25.2 ± 5.12 months. Of the patients in the study population, 53.5% were in the mild group, 30.4% in the moderate group, and 16.1% in the large group. PE became chronic in a total of 178 (69.6%) patients at the end of the mean three months, and chronicity increased as PE size increased. Despite the different anti-inflammatory treatments for PE in the acute phase, similar chronicity was observed. In addition, as the PE size increased, the patients' frequency of hospitalization, complications, and mortality rates showed statistical significance between the groups. Conclusions: The clinical prognosis of patients presenting with PE was quite poor; as PE in size increased, cardiac and noncardiac events and mortality rates were significantly higher. Patients with large PE associated with COVID-19 at discharge should be monitored at close intervals due to the chronicity of PE and the increased risk of tamponade.

Genotyping of Brucella isolates from animals and humans by Multiple-Locus Variable-number Tandem Repeat Analysis (MLVA).

This study investigates country-wide genotype variations through the genotyping of Brucella strains isolated from domestic ruminants and humans. The Brucella spp. isolated from samples taken from animals and humans were first identified as B. abortus and B. melitensis by real-time PCR, and the MLVA-16 approach was then used for the genotyping of the identified isolates. For the study, 416 Brucella spp. were isolated from aborted fetus samples examined between 2018 and 2021, and 74 Brucella spp. from infected humans. Of the 74 human isolates analyzed, 1.3% were identified as B. abortus and 98.7% (73/74) as B. melitensis. The MLVA-16 typing method revealed 30 clonal groups for B. abortus and 37 clonal groups for B. melitensis from which the dominant genotypes and similarities with human isolates in Türkiye were determined.

Molecular epidemiology of Coxiella burnetii detected in humans and domestic ruminants in Turkey.

Q fever is a zoonotic disease that is known to be widespread throughout the world by many researches since its discovery in 1935 and it is important in terms of animal and public health. Coxiella burnetii, which is the etiological agent of the disease, is an obligate intracellular pathogen. While the disease generally manifests itself with abortion in animals, disease manifests as atypical pneumonia or granulomatous hepatitis in the acute form and as endocarditis in the chronic form in humans. Its presence in Turkey has been shown with a large number of studies. The aim of this study was to show the genotypic relationship with MLVA analysis of C. burnetii samples found in cattle, sheep and goat samples in Erzurum and Samsun Veterinary Control Institutes and blood samples collected from humans with atypical pneumonia findings. In the study, MLVA analyses of 100 positive samples from 50 cows, 41 sheep and 9 goats from Northeast Anatolia and Black Sea regions and C. burnetii positive samples found in 6 individuals with atypical pneumonia were performed. As a result of the study, it was found that 106 C. burnetii samples had belong to 16 genotype groups. It was found that genotype XVI was the most prevalent among these groups and it was seen in both regions. In addition to this, genotype IX profile was the second largest group with 83.3% (5/6) of human samples. In this study, the genotypes common in the regions were determined and a data source was created for possible outbreaks.

Evaluating Multiple Biochemical Markers in Xenopus laevis Tadpoles Exposed to the Pesticides Thiacloprid and Trifloxystrobin in Single and Mixed Forms.

Pesticide exposure is thought to be one of the common reasons for the decline in amphibian populations, a phenomenon that is a major threat to global biodiversity. Although the single effects of pesticides on amphibians have been well studied, the effects of mixtures are not well known. The present study aimed to evaluate the acute toxicity of the insecticide thiacloprid and the fungicide trifloxystrobin on early developmental stages of Xenopus laevis using various biochemical markers (glutathione S-transferase, glutathione reductase, acetylcholinesterase, carboxylesterase, glutathione peroxidase, catalase, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, Na+ K+ -adenosine triphosphatase [ATPase], Ca2+ -ATPase, Mg2+ -ATPase, and total ATPase). The median lethal concentrations (LC50s) of thiacloprid and trifloxystrobin were determined to be 3.41 and 0.09 mg a.i. L-1 , respectively. Tadpoles were exposed to the LC50, LC50/2, LC50/10, LC50/20, LC50/50, and LC50/100 of these pesticides. Both pesticides significantly affected (inhibited/activated) the biomarkers even at low concentrations. The pesticides showed a synergistic effect when applied as a mixture and altered the biomarkers more than when applied individually. In conclusion, we can assume that tadpoles are threatened by these pesticides even at environmentally relevant concentrations. Our findings provide important data to guide management of the ecotoxicological effects of these pesticides on nontarget amphibians.  Environ Toxicol Chem 2021;40:2846-2860. © 2021 SETAC.

Developmental and lethal effects of glyphosate and a glyphosate-based product on Xenopus laevis embryos and tadpoles.

Effects of pure glyphosate and a glyphosate-based product were evaluated comparatively using two embryonic development stages of Xenopus laevis as model system. When pure glyphosate was applied in pH adjusted media, lethal or developmental effects were not observed at concentrations up to 500 mg L-1. The 96 h LC50 values for the commercial herbicide, in contrast, were 32.1 and 35.1 mg active ingredient L-1 for embryos and tadpoles, respectively. Since pure glyphosate has no effect on the selected biomarkers, it is thought that developmental toxic effects caused by glyphosate-based products are increased mainly due to formulation additives.

Photocatalytic degradation of azo dye using core@shell nano-TiO2 particles to reduce toxicity.

Clean and safe water is fundamental for human and environmental health. Traditional remediation of textile dye-polluted water with chemical, physical, and biological processes has many disadvantages. Due to this, nano-engineered materials are drawing more attention to this area. However, the widespread use of nano-particles for this purpose may lead to photocatalytic degradation of xenobiotics, while increasing the risk of nano-particle-induced ecotoxicity. Therefore, we comparatively evaluated the toxicity of novel synthesized core@shell TiO2 and SiO2 nano-particles to embryonic stages of Danio rerio and Xenopus laevis. The ability of photocatalytic destruction of the synthesized nano-particles was tested using toxic azo dye, disperse red 65, and the effects of reducing the toxicity were evaluated. The reflux process was used to synthesize catalysts in the study. The samples were characterized by scanning electron microscopy, X-ray fluorescence spectroscopy, X-ray diffractometry, BET surface area, and UV-vis-diffuse reflectance spectra. It was determined that the synthesized nano-particles had no significant toxic effect on D. rerio and X. laevis embryos. On the other hand, photocatalytic degradation of the dye significantly reduced lethal effects on embryonic stages of the organisms. Therefore, we suggest that specific nano-particles may be useful for water remediation to prevent human health and environmental impact. However, further risk assessment should be conducted for the ecotoxicological risks of nano-particles spilled in aquatic environments and the relationship of photocatalytic interaction with nano-particles and xenobiotics.

Comparative evaluation of toxicological effects and recovery patterns in zebrafish (Danio rerio) after exposure to phosalone-based and cypermethrin-based pesticides.

This study evaluated the toxic effects and recovery patterns in zebrafish (Danio rerio) after exposure to phosalone-based (PBP) and cypermethrin-based (CBP) pesticides. Initially, the 96 h LC50 values of the pesticides were calculated as being 5.35 µg of active ingredient (AI) L-1 for CBP and 217 µg AI L-1 for PBP based on measured concentrations. Accordingly, experimental groups were exposed to three sublethal concentrations of pesticides for 96 h, separately, and then zebrafish were transferred to pesticide-free conditions for 10 and 20 days recovery periods. Biochemical markers were assessed including carboxylesterase (CaE), acetylcholinesterase (AChE), glutathione S-transferase (GST), lactate dehydrogenase, glutathione peroxidase, catalase, alanine and aspartate aminotransferase (ALT, AST) activities after the exposure and recovery periods. Also, the pesticide concentrations in test water were quantified by high-performance liquid chromatography (HPLC) analysis. Our results showed that AChE and CaE activities were significantly inhibited and GST was induced by both pesticides after 96 h exposure. For PBP exposure, the decreases for GST induction and CaE inhibition showed a partial recovery in pesticide-free conditions. However, the decreases in AChE activity for CBP exposure and insufficient increases in same enzyme activity for PBP exposure after 20 days in pesticide-free conditions indicated that the projected recovery period was not enough to the recovery of AChE activities and for the improvement of fish health.

Monitoring of organic pollutants in marine environment by semipermeable membrane devices and mussels: accumulation and biochemical responses.

This study involves the monitoring of organic pollutants using transplanted mussels (Mytilus galloprovincialis) as bioindicator organisms and semipermeable membrane devices (SPMDs) as passive samplers. Mussels and SPMDs were deployed to marinas, shipyards and shipbreaking yards on the coastal area of Turkey and retrieved after 60 days. Polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and organochlorine pesticide (OCP) compounds were analysed with high-resolution GC-MS. Total PAH concentrations in SPMDs and mussels ranged from 200 to 4740 ng g sampler-1 and from 7.0 to 1130 ng g-1 in wet weight (ww). PCB and OCP concentrations in SPMDs changed between 0.04-200 and 4.0-26 ng g sampler-1, respectively. The highest PCB (190 ng g-1 ww) and OCP (200 ng g-1 ww) concentrations in mussels were measured at shipyard stations. A strong correlation was observed between the PAH and PCB concentrations in SPMDs and mussels. Enzyme assays (acetylcholinesterase, ethoxyresorufin-O-deethylase, glutathione S-transferase, glutathion reductase and carboxylesterase activities) were performed as biomarkers to reveal the effects of pollution on the mussels. There was no clear relationship found between the enzyme levels and the pollutant concentrations in mussels. Integrated biomarker responses were calculated to interpret the overall effect of pollutants.

Heavy metal pollution in sediments and mussels: assessment by using pollution indices and metallothionein levels.

In the present work, the concentration of eight metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) was determined in the sediments and transplanted and native mussels (Mytilus galloprovincialis). The study was conducted in Turkish marinas, shipyards, and shipbreaking yards. The effect of metal pollution was evaluated by determining the levels of metallothionein (MT) in the mussels. The extent of contamination for each single metal was assessed by using the geoaccumulation index (I geo) and enrichment factor (EF). Whereas, to evaluate the overall metal pollution and effect, the pollution load index (PLI), modified contamination degree (mC d), potential toxicity response index (RI), mean effects range median (ERM) quotient (m-ERM-Q), and mean PEL quotient (m-PEL-Q) were calculated. The influence of different background values on the calculations was discussed. The results indicated a significant metal pollution caused by Cu, Pb, and Zn especially in shipyard and shipbreaking sites. Higher concentrations of MT were observed in the ship/breaking yard samples after the transplantation.

Low concentrations of metal mixture exposures have adverse effects on selected biomarkers of Xenopus laevis tadpoles.

Polluted ecosystems may contain mixtures of metals, such that the combinations of metals, even in low concentrations, may cause adverse effects. In the present study, we focused on toxic effects of mixtures of selected metals, the LC50 values, and also their safety limit in aquatic systems imposed by the European legislation using a model organism. Xenopus laevis tadpoles were used as test organisms. They were exposed to metals or their combinations due to 96-h LC50 values. Glutathione S-transferase (GST), glutathione reductase (GR), acetylcholinesterase (AChE), carboxylesterase (CaE), glutathione peroxidase (GPx), and catalase (CAT) levels were evaluated. Metallothionein concentrations were also determined. The LC50s for Cd, Pb, and Cu were calculated as 5.81mg AI/L, 123.05mg AI/L, and 0.85mg AI/L, respectively. Low lethality ratios were observed with unary exposure of each metal in lower concentrations. Double or triple combinations of LC50 and LC50/2 concentrations caused 100% lethality with Cd+Cu and Pb+Cd+Cu mixtures, while the Pb+Cu mixture also caused high lethal ratios. The selected enzyme activities were significantly affected by metals or mixtures, and dose-related effects were determined. The metallothionein levels generally increased as related to concentration in unary metals and mixtures. Acceptable limit values of unary metals and mixtures did not significantly change metallothionein levels. The results suggest that oxidative stress-related mechanisms are involved in the toxicity induced by selected metals with combinations of very low concentrations.

Toxicological aspects of photocatalytic degradation of selected xenobiotics with nano-sized Mn-doped TiO2.

The toxic effects of two selected xenobiotics, bisphenol A (BPA) and atrazine (ATZ), were evaluated after photocatalytic degradation using nano-sized, Mn-doped TiO2. Undoped and Mn-doped TiO2 nanoparticles were synthesized. The samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), UV-vis-diffuse reflectance spectra (DRS), X-ray fluorescence spectroscopy (XRF), and BET surface area. The photocatalytic efficiency of the undoped and Mn-doped TiO2 was evaluated for BPA and ATZ. The toxicity of the synthesized photocatalysts and photocatalytic by-products of BPA and ATZ was determined using frog embryos and tadpoles, zebrafish embryos, and bioluminescent bacteria. Possible toxic effects were also evaluated using selected enzyme biomarkers. The results showed that Mn-doped TiO2 nanoparticles did not cause significant lethality in Xenopus laevis embryos and tadpoles, but nonfiltered samples caused lethality in zebrafish. Furthermore, Mn-doping of TiO2 increased the photocatalytic degradation capability of nanoparticles, and it successfully degraded BPA and AZT, but degradation of AZT caused an increase of the lethal effects on both tadpoles and fish embryos. Degradation of BPA caused a significant reduction of lethal effects, especially after 2-4h of degradation. However, biochemical assays showed that both Mn-doped TiO2 and the degradation by-products caused a significant change of selected biomarkers on X. laevis tadpoles; thus, the ecological risks of Mn-doped TiO2 should be considered due to nanomaterial applications and for spilled nanoparticles in an aquatic ecosystem. Also, the risk of nanoparticles should be considered using indicator reference biochemical markers to verify the environmental health impacts.

Evaluation of in vitro and in vivo toxic effects of newly synthesized benzimidazole-based organophosphorus compounds.

This paper reports the toxic properties of eight newly synthesized benzimidazole-based organophosphorus (OP) compounds in Xenopus laevis in both in vivo and in vitro conditions. For both experiments, a commercial solution of azinphos methyl (AzM, Gusathion M WP25) was used as a reference compound. The 24-h median lethal concentrations (LC50) of all tested compounds were determined for 46th stage tadpoles in the range of 9.54-140.0 µM. For evaluation of the lethality of the compounds, the activity of the enzyme biomarkers acetylcholinesterase (AChE), carboxylesterase, glutathione S-transferase (GST), glutathione peroxidase, glutathione reductase, lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase were determined in vivo in X. laevis tadpoles exposed to three concentrations (LC50, LC50/2, and LC50/4) of tested compounds. All exposure concentrations of AzM and seven of eight tested compounds caused CaE inhibition in in vivo conditions. Furthermore, the AChE inhibition capacity of tested compounds in commercial electric eel AChE and in X. laevis homogenates and also CaE inhibition capacity in only X. laevis homogenates were assayed for a 30-min in vitro exposure period. Eight OP compounds did not inhibit AChE activity more than 23 percent, but AzM exposure inhibited AChE activity by 26 percent for X. laevis homogenates and 97 percent for electric fish AChE in in vitro conditions. Also, CaE inhibition levels in X. laevis tadpole homogenates were 46 percent for AzM and between 8 percent and 33 percent for other compounds in in vitro conditions.

Biochemical response to exposure to six textile dyes in early developmental stages of Xenopus laevis.

The present study was undertaken to determine the toxic effect of a lethal concentration of six different commercially used textile dyes on the 46th stage of Xenopus laevis tadpoles. The tadpoles were exposed to Astrazon Red FBL, Astrazon Blue FGRL, Remazol Red RR, Remazol Turquoise Blue G-A, Cibacron Red FN-3G, and Cibacron Blue FN-R for 168 h in static test conditions, and thus, 168-h median lethal concentrations (LC(50)s) of each dye were determined to be 0.35, 0.13, 112, 7, 359, and 15.8 mg/L, respectively. Also, to evaluate the sublethal effects of each dye, tadpoles were exposed to different concentrations of dyes (with respect to 168-h LC(50)s) for 24 h. The alteration of selected enzyme activities was tested. For this aim, glutathione S-transferase (GST), carboxylesterase, and lactate dehydrogenase (LDH) were assayed. After dye exposure, the GST induction or inhibition and LDH induction indicated some possible mechanisms of oxidative stress and deterioration in aerobic respiration processes induced by the tested dyes. Findings of the study suggest that selected biomarker enzymes are useful in understanding the toxic mechanisms of these dyes in X. laevis tadpoles as early warning indicators. Therefore, these selected biomarkers may evaluate the effect of environmental factors, such as textile dye effluents and other industrial pollutants, on amphibians in biomonitoring studies.

Toxic effects of deltamethrin and λ-cyhalothrin on Xenopus laevis tadpoles.

This study evaluates the toxic effects of deltamethrin and λ-cyhalothrin on Xenopus laevis tadpoles after 168 h of exposure. The LC(50) of deltamethrin and λ-cyhalothrin at 168 h was calculated as the µg of active ingredient per liter (µg AI/L). According to these values, the LC(50) was 6.26 and 3.94 µg AI/L for deltamethrin and λ-cyhalothrin, respectively. Several enzymes were studied for early signs of intoxication following exposure to the pesticides for 24 h. Glutathione-S-transferase,carboxylesterase, and lactate dehydrogenase were inhibited by λ-cyhalothrin, and both pesticides inhibited acid phosphatase and aspartate aminotransferase. In contrast, acetylcholinesterase was activated by deltamethrin. The results suggest that X. laevis is sensitive to the pyrethroids that were tested, and the enzyme responses suggest that they are potential biomarkers for evaluating the toxic effect of pyrethroids on amphibians in environmental conditions.