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Biomedical subjects

R Szabó

Publications and source records attributed to R Szabó.

At least 19 recordsLinked to original sources
PubMed2005

Early embryogenesis study on a dimethoate containing formulation and Cd-sulphate in chicken embryos.

The toxic effects of a widely used organophosphate insecticide (BI 58 EC containing 38% dimethoate as active ingredient) applied alone or in combination with cadmium sulphate modelling the heavy metal load of the environment were studied on chicken embryos in the early phase of development. Solutions and emulsions of different concentrations were made from the test materials and injected in 0.1 ml volume into the air space of eggs on the first day (day 0) of incubation. Subsequently, on days 2 and 3 of incubation permanent preparations were made from the embryos in order to study the early developmental stage. Embryos fixed on slides and stained with osmium tetroxide solution were studied under light microscope. Summarising the findings, it can be established that the embryotoxicity increased after the simultaneous administration of Cd-sulphate and 38% dimethoate containing insecticide formulation compared to the control or the individually treated groups.

Abnormalities, Drug-Induced↗
PubMed2004

Teratogenicity study of some pesticides in chicken embryos.

The use of pesticides involves the risk of poisoning on wild animals. Teratological tests carried out on avian embryos provide useful data for environmental protection and facilitate the development of environment-friendly chemical plant protection techniques. A 30% dimethoate containing insecticide formulation (BI 58 EC) and a 20% benfluralin containing herbicide formulation (Flubalex) and a 960 g/l S-metolachlor containing herbicide formulation (Dual Gold 960 EC) were studied in chicken embryos after single administration by immersion and injection technique. Treatment was done on day 0 of incubation. Applied concentration of pesticides were 0.1% (dimethoate) and 2.05% (S-metolachlor) and 0.375% (benfluralin) corresponding to that used in plant protection practice. Test materials were injected into the air chamber in a volume of 0.1 ml/egg, or eggs were treated by the immersion technique for 30 min. at 37 degrees C. Evaluation was done on day 19 of incubation. Injection treatment: the administration of S-metolachlor and benfluralin did not result a significant decrease in the average body weight of embryos. At the same time the body weight of embryos significantly decreased because of single administration of dimethoate. The embryomortality increased markedly after the administration of test materials (S-metolachlor, benfluralin, dimethoate). Immersion treatment: the administration of S-metolachlor and benfluralin and dimethoate did not result a significant decrease in the average body weight of embryos. The rate of embryomortality was low after the administration of S-metolachlor, benfluralin and dimethoate. After the immersion and the injection treatment the incidences of developmental anomalies were sporadic. In summary it can be established that the injection treatment was more toxic than immersion technique of the test materials in our study.

Animals↗
PubMed2004

Toxicity of a dichlorvos containing insecticide formulation and an atrazine containing herbicide formulation in chicken embryos after individual administration.

A 50% dichlorvos containing insecticide formulation (Unifosz 50 EC) and a 50% atrazine containing herbicide formulation (Hungazin PK 50 WP) were studied in chicken embryos after administration as single compounds. Applied concentrations of dichlorvos were 0.1% (corresponding to the plant protection practice), 0.05%, 0.02%, 0.01%. Applied concentrations of atrazine were 0.66% (corresponding to the plant protection practice), 0.33%, 0.132%, 0.066%. The test materials were injected directly into the air-chamber of eggs on day 0 of the hatching period and evaulation was carried out on day 19 of incubation. The chicken embryos were examined for the following: rate of embryo mortality, body mass, type of developmental anomalies. After the single administrations of dichlorvos containing insecticide formulation and atrazine containing herbicide formulation on day 0 of incubation, the average body weight of chicken embryos significantly did not decrease as compared to the control. After the individual administrations of pesticides the incidence of developmental anomalies was sporadic. The embryonic mortality markedly increased at the highest concentrations of pesticides. The rate of embrio mortality were 61% (dichlorvos insecticide containing formulation) and 52% (atrazine containing herbicide formulation). In summary, the 50% dichlorvos containing insecide formulation (Unifosz 50 EC) and the 50% atrazine containing herbicide formulation (Hungazin PK 50 WP) were toxic to the developing chicken embryos at the highest concentration in our study. The toxic effect was expressed in the high rate of embrio mortality.

Animals↗
PubMed2003

Interfacial interactions between poly[L-lysine]-based branched polypeptides and phospholipid model membranes.

The interaction of five poly[L-lysine]-derived branched chain polypeptides of poly[Lys(X(i))] (X(i)K) or poly[Lys(X(i)-DL-Ala(m))] (XAK) with lipid bilayers (DPPC and DPPC/PG, 8:2) was studied by fluorescence polarization techniques. Two fluorescent probes, DPH and TMA-DPH, were utilized to monitor changes of motion in the internal and/or in the polar head regions, respectively. Results indicate that the interaction of polypeptides with neutral (DPPC) bilayers is mainly dependent on the polarity and electrical charge of side chains. The amphoteric E(i)K shows the highest level of interaction. Polycationic polypeptides (H(i)K, P(i)K, TAK) have a relatively small effect on the transition temperature of the lipids, while the polyanionic Succ-EAK has no effect at the alkyl chain region of the bilayer. Data with TMA-DPH indicate the lack of pronounced interaction between the polypeptides and the outer surface of the liposome. Similar tendency was documented for DPPC/PG vesicles. Polypeptides, H(i)K, and P(i)K induce significant changes in the transition temperature, thus indicating their insertion into the hydrophobic core of the bilayer without marked effect on the polar head region. Results suggest that these polypeptides (except E(i)K) have no destabilizing effect on liposomes studied. These properties are considered as beneficial for their use as safe carriers for bioactive molecules.

Fluorescence Polarization↗
PubMed2003

Embryonic toxicity of a mancozeb containing fungicide formulation and Cu-sulphate in pheasant after individual or combined administration.

Cu-sulphate and a 80% mancozeb containing fungicide formulation (Dithane M-45) were studied in pheasants after administration as single compounds or in combination. The test materials were injected directly into the air-chamber of eggs on day 12 of the hatching period and evaulation was carried out on day 23 of incubation. The pheasant embryos were examined for the following: rate of embryo mortality, body mass, type of developmental anomalies, light microscopic examination. After the administration of copper-sulphate on day 12 of incubation, the average body weight of pheasant embryos significantly did not decrease as compared to the control. The embryonic mortality was 68%. After the administration of a mancozeb containing fungicide formulation (Dithane M-45) on day 12 of incubation, the average body weight of embryos did not decrease as compared to the control. The embryonic mortality was 50%. After the individual administration of pesticide, the incidence of developmental anomalies was very high. After the combined administration of copper-sulphate and the 80% mancozeb containing fungicide formulation (Dithane M-45) on day 12 of incubation the embryonic mortality markedly increased. The rate of embryo mortality was 93%. We did not find any degenerative change in the liver tissue in either the control group or the treated groups by light microscopic examination. In summary, it can be established that the simultaneous administration of Cu-sulphate and mancozeb containing fungicide formulation caused high toxicity compared with the individual toxicity of test materials.

Animals↗
PubMed2003

Toxicity and degradation of metolachlor (Dual Gold 960 EC) in chicken embryos.

The herbicide formulation Dual Gold 960 EC (960 g/l metolachlor) was applied, ROSS 308 embryonated hen eggs were treated on day 12 of incubation period. The pesticide was diluted in water to a concentration level 0.3% and the emulsion was injected into the air space in a volume of 0.1 ml/egg, or hen's eggs were treated by the immersion technique (30 min). Residues of metolachlor were measured by GC in 14 collected embryo samples on days 13, 15 and 19 of the incubation of chicken embryos, and macro- and microscopic morphological examinations of 49 embryos were performed simultaneously on day 19. Body mass of embryos was weighed on 13th, 15th and 19th day of incubation. After the both treatments the mortality rate of embryos was similar. The average data of body mass showed a significant decrease compared to the control in the immersion study on day 15 and 19 of the hatching period. This phenomenon may only be in connection with the presence of metolachlor over the limit of quantification (LOQ) on day 13 of incubation period. The macroscopic deformations were sporadic in the embryos. No histologically detected alterations were seen.

Abnormalities, Drug-Induced↗
PubMed2002

Embryonic toxicity of a dimethoate containing insecticide formulation and Cu-sulphate in chicken after individual or combined administration.

The aim of this study was to determine the individual and combined toxic effects of a dimethoate containing insecticide formulation and Cu-sulphate on the development of chicken embryos. The test materials were injected directly into the air-chamber in a volume of 0.1 ml/egg, or eggs were treated by immersion technique on day 12. Applied concentration of Cu-sulphate was 0.01% and the concentration of insecticidE was 0.1%. After the injection treatment of a dimethoate containing insecticide on day 12 of incubation, the average body mass of embryos significantly decreased. The simultaneous injections of Cu-sulphate and a dimethoate containing insecticide a statistically significant reduction in embryonic body mass occurred. Embryonic mortality did not increase after the individual injection of test materials, while the combined injection of Cu-sulphate and a dimethoate containing insecticide killed 30% of embryos treated. After the individual and combined immersion treatment of Cu-sulphate and a dimethoate containing insecticide, the average body mass of embryos did not decrease significantly as compared to the control. After the combined immersion treatment the incidence of embryonic mortality and the number of embryos with developmental anomalies did not differ markedly from the control. In summary, it can be established that the combined injection treatment of Cu-sulphate and a dimethoate containing insecticide caused higher embryotoxicity with respect to the test of the combined immersion treatment of test materials.

Animals↗
PubMed2002

Toxicity of a mancozeb containing fungicide formulation and CU-sulphate to chicken embryos after administration as single compounds or in combination.

Environmental pollution of metal modelled by copper-sulphate and a 80% mancozeb containing fungicide formulation (Dithane M-45) were studied on chicken embryos after administration as a single compounds or in combination. The test materials were injected into the air-chamber in a volume of 0.1 ml/egg on day 12 of incubation. The concentration of copper-sulphate was 0.01%. The applied concentration of Dithane M-45 fungicide formulation was 0.2%. Evaluation was done on day 19 of the hatching period. The combined administration of copper-sulphate and the fungicide formulation did not cause a significant reduction in body weight as compared to the control data and the results from individual toxicity study of the test materials. After the combined administration of copper-sulphate and the fungicide formulation the rate of embryomortality was 40%. The incidence of developmental anomalies were sporadic. Light microscopic findings exhibited a degenerative change in the liver tissue of combined administration group. Activities of GPT and GOT enzymes increased markedly in the combined administration group. In summary, it can be established that the interaction of copper-sulphate and an 80% mancozeb containing fungicide formulation (Dithane M-45) caused higher embryomortality with respect to the test of individual toxicity of copper-sulphate and fungicide in our study.

Alanine Transaminase↗
PubMed2001

Minor physical anomalies in schizophrenia and bipolar affective disorder.

OBJECTIVE: The prevalence of minor physical anomalies (MPAs) (prenatal errors of morphogenesis) was evaluated in patients with schizophrenia and bipolar affective disorder. METHOD: A new modification of the Waldrop-scale was used to detect the presence or absence of 57 MPAs in 30 patients with schizophrenia, 30 with bipolar disorder, and in 30 matched normal controls. RESULTS: Patients with schizophrenia compared to normal controls had significantly higher rates of three minor malformations (furrowed tongue, flat occiput, primitive shape of ears) and those of one phenogenetic variant (wide distance between toes 1 and 2), and they also had a significantly higher rate of one minor malformation (primitive shape of ears), as compared to patients with bipolar disorder. In patients with bipolar disorder, furrowed tongue was significantly more common than in controls. CONCLUSIONS: These results support an 'early' neuro-developmental model of schizophrenia.

Abnormalities, Multiple↗
PubMed2000

Assessment of ovulation of common carp (Cyprinus carpio) females selected for induced spawning on the basis of external morphological characteristics.

Secondary sexual characteristics such as softening and rounding of the abdomen as well as reddening and protrusion of the anal papilla and vent can be of help to breeders in selecting common carp (Cyprinus carpio) females prepared for propagation. To assess the reliability of this method, long-term data obtained on induced spawning of common carp at a large-scale fish hatchery were evaluated. The average spawning ratio of 2,620 females receiving hormonal injections was 79.8%. The average pseudogonadosomatic index (PGSI) calculated from data on the egg production of 2,086 females was 16.3 +/- 5.87% (mean +/- SD) for the same period. There was a correlation between fish weight and the time of induction determined by the breeder on the basis of external morphological characteristics. The similarity of the responses of females, including both spawning ratio and PGSI, among the different weight categories proved the reliability of this method for identification.

Abdomen↗
PubMed1998

Synthesis, solution conformation and interleukin-6-related activities of interleukin-6 peptides.

Interleukin-6 (IL-6) is a member of the cytokine superfamily characterised by a wide variety of biological activities on various cell types. IL-6 exerts pleiotropic activities on hematopoiesis in the immune response and it is the main regulator of acute-phase protein synthesis in liver cells. According to structure-function studies, residues of helix A located at the N-terminal part and/or helix D of the C-terminal part of the protein are involved in the induction of acute-phase responses. Two groups of synthetic peptides corresponding to the 18-46 N-terminal and the 168-185 C-terminal regions of the IL-6 were prepared by solid-phase synthesis to identify structural requirements for induction of fibrinogen or complement factor B synthesis. These peptides were characterised by amino acid analysis, analytical reversed-phase high-performance liquid chromatography, fast atom bombardment mass spectrometry, and circular dichroism (CD) spectroscopy. CD results showed that under appropriate conditions both 18-46 and 168-185 related peptides are able to adopt markedly ordered conformation. We demonstrated that even octapeptides from the N-terminal part and truncated derivatives of the C-terminal region preserved some tendency to display the CD curve of periodic conformation. The ability of the peptides to induce de novo synthesis of acute-phase proteins was evaluated by measuring fibrinogen and complement factor B levels in the supernatants of human HepG2 cells. These results showed that residues 21-34 are critical for eliciting fibrinogen synthesis in the presence or absence of IL-6. In contrast, the full-length 168-185 peptide is required for the induction of complement factor B response.

Acute-Phase Proteins↗
PubMed1989

[Antibiotic prophylaxis in cesarean section using a single dose of rocephin].

On the basis of random selection 1 g of Rocephin was given to 36 parturients following Cesarean section to prevent postoperative febrile diseases. The results confirm the role of antibiotic prophylaxis in the prevention of perioperative infections. If only partial prophylaxis may be applied preference has to be given to the so called risk cases.

Bacterial Infections↗