Pesticide Use and Degradation Strategies: Food Safety, Challenges and Perspectives

While recognizing the gaps in pesticide regulations that impact consumer safety, public health concerns associated with pesticide contamination of foods are pointed out. The strategies and research directions proposed to prevent and/or reduce pesticide adverse effects on human health and the environment are discussed. Special attention is paid to organophosphate pesticides, as widely applied insecticides in agriculture, veterinary practices, and urban areas. Biotic and abiotic strategies for organophosphate pesticide degradation are discussed from a food safety perspective, indicating associated challenges and potential for further improvements. As food systems are endangered globally by unprecedented challenges, there is an urgent need to globally harmonize pesticide regulations and improve methodologies in the area of food safety to protect human health

Repair kinetics of DNA double-strand breaks induced by ionising radiation and crosslinking agents in vitro

Sindromi genomske nestаbilnosti nastaju kao posledica mutаcija u genimа koji kodiraju proteine uključene u odgovor na oštećenje i popravku DNK. Većinа tih bolesti pokаzuje slične in vitro ćelijske fenotipove; specifičan ćelijski ciklus, povećаnu osetljivost nа oksidativni stres i sklonost ka razvoju maligniteta. Jedan od retkih, ali sa aspekta rаzumevаnja ćelijskog odgovorа nа ozledu DNK, značajnih sindroma genomske nestabilnosti je Fankonijeva anemija. Osnovno obeležje FA ćelijskog fenotipa je visok nivo spontаnih hromozomskih prekida, koji se može povećаti izlaganjem ovih ćelijа alkilirajućim agensima, kаo što su mitomicin C i diepoksibutаn (DEB). Mаnje poznаta i još uvek spornа kаrаkteristikа FA ćelijа je njihovа rаdioosetljivost. S obzirom da je primenа jonizujućeg zrаčenjа često jedinа opcija u lečenju tаkvih bolesti pred trаnsplаntаciju kostne srži, proučаvаnje odgovorа nа jonizujuće zrаčenje i njihove rаdioosetljivosti je od fundamentalnog znаčаja. Osnovni cilj ovog istraživanja je bio ispitati odgovor na DNK oštećenja indukovana jonizujućim zračenjem i alkilirajućim agensima in vitro kod fibroblasta pacijenta obolelih od Fankonijeve anemije. Budući da Fankonijeva anemija pripada grupi oboljenja koje karakterišu defekti proteina uključenih u odgovor na oštećenja indukovana jonizujućim zračenjem, vršena je analiza γ-H2АX kao markera dvolančanih prekida. U ovom istraživanju je praćena kinetika oporavka dvolanačanih prekida indukovanih zračenjem i diepoksibutanom kao alkilirajućim agensom u primarnim fibroblastima pacijenta obolelih od aplazije kostne srži, uključujući i FA pacijente, primenom γ-H2АX metode, analizom mikronukleusa, ćelijskog ciklusa, apoptoze i pojedinačnih nukleotidnih izmena ciljnih gena. Rezultati su pokazali da se FA pаcijenti mogu rаzlikovаti od ostаlih pacijenata sa aplazijom kostne srži (BMF), nа osnovu γ-H2AX testa 24 h nаkon izlаgаnjа ćelijа jonizujućem zrаčenju (p<0.05). U FA ćelijama učestаlost rezidualnih γ-H2AX fokusa je približno 3 putа veća u odnosu nа BMF i kontrolne ćelije i u proseku 9 putа veća u odnosu nа stаnje pre zrаčenjа (p<0.05). Metod γ-H2AX je brz i osetljiv test, koji se može koristiti za neposrednu dijagnozu individualnog FA ćelijskog fenotipa. Kаšnjenje u kinetici poprаvke zrаčenjem indukovаnih dvolančanih prekida u FA fibroblastima može se smаtrаti merom konstitutivne rаdioosetljivosti pre određivanja i primene doze zа trаnsplаntаciju hemаtopoetskih mаtičnih ćelijа. Sa druge strane, CB-MN testom je nemoguće proceniti konstitutivnu radioosetljivost FA pacijenata, ali uočeno povećanje indukovanih mikronukleusa u FA grupi u odnosu na BMF grupu ipak ne isključuje primenu ovog testa kao dopunskog, posebno u većim studijama. Ćelije FA pacijenata imaju poremećaj u regulaciji ćelijskog ciklusa i apoptoze; nakon ozračivanja većina ćelija se zaustavlja u G2/M fazi, što je praćeno malim procentom ćelija koje podležu apoptozi, dok nakon tretmana DEB-om FA ćelije značajno kasne sa ulaskom u apoptozu. Pojedinačne nukleotidne izmene gena uključenih u puteve popravke DNK i regulaciju ćelijskog ciklusa ukazuju na lošiju prognozu i veću sklonost ka razvoju tumora pacijenta obolelih od FA u odnosu na BMF pacijente. Naše istraživanje na FA fibroblastnim ćelijama potvrđuje da je ovo "oboljenje DNK reparacije'' i istovremeno ukazuje koliki je značaj neoštećenog FA puta u očuvanju genomske stabilnosti. Utvrđeno kašnjenje u kinetici popravke zračenjem indukovanih dvolančanih prekida u fibroblastima FA pacijenata, pruža mogućnost za novi pristup u diferencijalnoj dijagnostici FA ćelijskog fenotipa i prediktivnim testovima za transplanataciju kostne srži.The genomic instability syndromes result from mutations in genes that encode proteins involved in response to DNA damage and repair. Most of these diseases show similar cellular phenotypes in vitro, the specific cell cycle, increased susceptibility to oxidative stress and susceptibility to malignancy. Fanconi anemia is a rare genomic instability syndrome characterized by diverse developmental abnormalities, progressive bone marrow failure (BMF) and predisposition to both hematological malignancies and solid tumors. The hallmark of the FA cellular phenotype is sensitivity to DNA cross-linking agents such as mitomycin C and diepoxybutane (DEB) and such sensitivity is used in the diagnosis of Fanconi anemia. However, results obtained after exposure of FA cells to ionizing radiation are not uniform. The aim of this study was to investigate the response to ionizing radiation and cross-linking agents of Fanconi anemia fibroblasts in vitro. Assuming that Fanconi anemia belongs to human disorders that are conferred by defects in proteins that function in response to double strand breaks (DSBs), a newly developed marker of DSBs γ-H2AX, is used to study response and sensitivity to ionizing radiation. In this study, we evaluated repair kinetics of radiation and DEB-induced DNA damages in primary fibroblasts of bone marrow failure (BMF) patients including FA patients employing γ-H2AX assay, CB-MN test, cell cycle analysis, apoptosis assay and single nucleotid polmorphism in target genes. Cell lines originating from FA patients displayed a significant delay in the repair of radiation-induced DNA DSBs relative to BMF and control cell lines (p<0.05). The delay is especially evident at recovery time of 24 hours, and is seen as about 9-fold increase of residual γ-H2AX foci compared to self-state before irradiation (p<0.05). In FA cells frequencies of residual γ-H2AX foci is approximately 3-fold higher compared to BMF and control cells. Delayed repair kinetics of FA cells confirms the nature of FA as a DNA repair disease, and at the same time gives an opportunity to make diagnosis of FA easier. The observed delay in repair kinetics of FA cells represents a special mode of intrinsic radiosensitivity, which can be exploited to discriminate FA from non-FA BMF patients and prevent major toxicity in standard dose-conditioning regimens for hematopoietic stem cell transplantation. On the other hand, CB-MN assay is insufficient for estimation of the constitutive radiosensitivity of FA patients, but observed increase of induced micronuclei in the FA group compared to the BMF group, does not exclude its employment as supplementary diagnostic test. FA cells show abnormalities in the regulation of cell cycle and apoptosis. After irradiation majority of FA cells are permanently arrested in G2/M, which is followed with very low number of cells entering apoptosis, while after DEB treatment significant delay in entering apoptosis was observed. Single nucleotide polymorphisms in DNA repair genes and genes responsible for cell cycle regulation indicate an increased susceptibility toward malignancies in FA patients compared to BMF patients. This study confirmed Fanconi anemia as the ''DNA repair'' disease and indicates significance of undamaged FA pathway in maintaining genomic stability. The delay in repair kinetics of FA cells gives an opportunity for straightforward diagnosis of individual FA cellular phenotype and helps as predictive test for bone marrow transplantation

Repair kinetics of DNA double-strand breaks induced by ionising radiation and crosslinking agents in vitro

Sindromi genomske nestаbilnosti nastaju kao posledica mutаcija u genimа koji kodiraju proteine uključene u odgovor na oštećenje i popravku DNK. Većinа tih bolesti pokаzuje slične in vitro ćelijske fenotipove; specifičan ćelijski ciklus, povećаnu osetljivost nа oksidativni stres i sklonost ka razvoju maligniteta. Jedan od retkih, ali sa aspekta rаzumevаnja ćelijskog odgovorа nа ozledu DNK, značajnih sindroma genomske nestabilnosti je Fankonijeva anemija. Osnovno obeležje FA ćelijskog fenotipa je visok nivo spontаnih hromozomskih prekida, koji se može povećаti izlaganjem ovih ćelijа alkilirajućim agensima, kаo što su mitomicin C i diepoksibutаn (DEB). Mаnje poznаta i još uvek spornа kаrаkteristikа FA ćelijа je njihovа rаdioosetljivost. S obzirom da je primenа jonizujućeg zrаčenjа često jedinа opcija u lečenju tаkvih bolesti pred trаnsplаntаciju kostne srži, proučаvаnje odgovorа nа jonizujuće zrаčenje i njihove rаdioosetljivosti je od fundamentalnog znаčаja. Osnovni cilj ovog istraživanja je bio ispitati odgovor na DNK oštećenja indukovana jonizujućim zračenjem i alkilirajućim agensima in vitro kod fibroblasta pacijenta obolelih od Fankonijeve anemije. Budući da Fankonijeva anemija pripada grupi oboljenja koje karakterišu defekti proteina uključenih u odgovor na oštećenja indukovana jonizujućim zračenjem, vršena je analiza γ-H2АX kao markera dvolančanih prekida. U ovom istraživanju je praćena kinetika oporavka dvolanačanih prekida indukovanih zračenjem i diepoksibutanom kao alkilirajućim agensom u primarnim fibroblastima pacijenta obolelih od aplazije kostne srži, uključujući i FA pacijente, primenom γ-H2АX metode, analizom mikronukleusa, ćelijskog ciklusa, apoptoze i pojedinačnih nukleotidnih izmena ciljnih gena. Rezultati su pokazali da se FA pаcijenti mogu rаzlikovаti od ostаlih pacijenata sa aplazijom kostne srži (BMF), nа osnovu γ-H2AX testa 24 h nаkon izlаgаnjа ćelijа jonizujućem zrаčenju (p<0.05). U FA ćelijama učestаlost rezidualnih γ-H2AX fokusa je približno 3 putа veća u odnosu nа BMF i kontrolne ćelije i u proseku 9 putа veća u odnosu nа stаnje pre zrаčenjа (p<0.05). Metod γ-H2AX je brz i osetljiv test, koji se može koristiti za neposrednu dijagnozu individualnog FA ćelijskog fenotipa. Kаšnjenje u kinetici poprаvke zrаčenjem indukovаnih dvolančanih prekida u FA fibroblastima može se smаtrаti merom konstitutivne rаdioosetljivosti pre određivanja i primene doze zа trаnsplаntаciju hemаtopoetskih mаtičnih ćelijа. Sa druge strane, CB-MN testom je nemoguće proceniti konstitutivnu radioosetljivost FA pacijenata, ali uočeno povećanje indukovanih mikronukleusa u FA grupi u odnosu na BMF grupu ipak ne isključuje primenu ovog testa kao dopunskog, posebno u većim studijama. Ćelije FA pacijenata imaju poremećaj u regulaciji ćelijskog ciklusa i apoptoze; nakon ozračivanja većina ćelija se zaustavlja u G2/M fazi, što je praćeno malim procentom ćelija koje podležu apoptozi, dok nakon tretmana DEB-om FA ćelije značajno kasne sa ulaskom u apoptozu. Pojedinačne nukleotidne izmene gena uključenih u puteve popravke DNK i regulaciju ćelijskog ciklusa ukazuju na lošiju prognozu i veću sklonost ka razvoju tumora pacijenta obolelih od FA u odnosu na BMF pacijente. Naše istraživanje na FA fibroblastnim ćelijama potvrđuje da je ovo "oboljenje DNK reparacije'' i istovremeno ukazuje koliki je značaj neoštećenog FA puta u očuvanju genomske stabilnosti. Utvrđeno kašnjenje u kinetici popravke zračenjem indukovanih dvolančanih prekida u fibroblastima FA pacijenata, pruža mogućnost za novi pristup u diferencijalnoj dijagnostici FA ćelijskog fenotipa i prediktivnim testovima za transplanataciju kostne srži.The genomic instability syndromes result from mutations in genes that encode proteins involved in response to DNA damage and repair. Most of these diseases show similar cellular phenotypes in vitro, the specific cell cycle, increased susceptibility to oxidative stress and susceptibility to malignancy. Fanconi anemia is a rare genomic instability syndrome characterized by diverse developmental abnormalities, progressive bone marrow failure (BMF) and predisposition to both hematological malignancies and solid tumors. The hallmark of the FA cellular phenotype is sensitivity to DNA cross-linking agents such as mitomycin C and diepoxybutane (DEB) and such sensitivity is used in the diagnosis of Fanconi anemia. However, results obtained after exposure of FA cells to ionizing radiation are not uniform. The aim of this study was to investigate the response to ionizing radiation and cross-linking agents of Fanconi anemia fibroblasts in vitro. Assuming that Fanconi anemia belongs to human disorders that are conferred by defects in proteins that function in response to double strand breaks (DSBs), a newly developed marker of DSBs γ-H2AX, is used to study response and sensitivity to ionizing radiation. In this study, we evaluated repair kinetics of radiation and DEB-induced DNA damages in primary fibroblasts of bone marrow failure (BMF) patients including FA patients employing γ-H2AX assay, CB-MN test, cell cycle analysis, apoptosis assay and single nucleotid polmorphism in target genes. Cell lines originating from FA patients displayed a significant delay in the repair of radiation-induced DNA DSBs relative to BMF and control cell lines (p<0.05). The delay is especially evident at recovery time of 24 hours, and is seen as about 9-fold increase of residual γ-H2AX foci compared to self-state before irradiation (p<0.05). In FA cells frequencies of residual γ-H2AX foci is approximately 3-fold higher compared to BMF and control cells. Delayed repair kinetics of FA cells confirms the nature of FA as a DNA repair disease, and at the same time gives an opportunity to make diagnosis of FA easier. The observed delay in repair kinetics of FA cells represents a special mode of intrinsic radiosensitivity, which can be exploited to discriminate FA from non-FA BMF patients and prevent major toxicity in standard dose-conditioning regimens for hematopoietic stem cell transplantation. On the other hand, CB-MN assay is insufficient for estimation of the constitutive radiosensitivity of FA patients, but observed increase of induced micronuclei in the FA group compared to the BMF group, does not exclude its employment as supplementary diagnostic test. FA cells show abnormalities in the regulation of cell cycle and apoptosis. After irradiation majority of FA cells are permanently arrested in G2/M, which is followed with very low number of cells entering apoptosis, while after DEB treatment significant delay in entering apoptosis was observed. Single nucleotide polymorphisms in DNA repair genes and genes responsible for cell cycle regulation indicate an increased susceptibility toward malignancies in FA patients compared to BMF patients. This study confirmed Fanconi anemia as the ''DNA repair'' disease and indicates significance of undamaged FA pathway in maintaining genomic stability. The delay in repair kinetics of FA cells gives an opportunity for straightforward diagnosis of individual FA cellular phenotype and helps as predictive test for bone marrow transplantation

Positive correlation between micronuclei and necrosis of lymphocytes in medical personnel occupationally exposed to ionizing radiation

BACKGROUND: Current radiation protection standards are based on premise that any radiation dose may result in detrimental health effects. The aim of this study was to evaluate extent of the DNA damages (measured by induction of micronuclei) and interphase cell death in circulating lymphocytes of medical personnel exposed to ionizing radiation. METHODS: Baseline micronuclei were assessed using the cytokinesis-block micronucleus test. Cytotoxicity was analyzed by flow cytometry for human white blood cells to identify cells that displayed apoptosis-associated DNA condensation. Necrotic cells were analyzed simultaneously. All parameters were compared with corresponding controls. RESULTS: A statistically significant difference (t = 4.54, p = 0.002) was found between exposed and control group in the yield of baseline micronuclei. The level of baseline micronuclei correlated positively with necrosis of leucocytes (r=0.09, p=0.68 in exposed group, r=0.02, p=0.97 in controls). An inverse correlation between baseline micronuclei and apoptosis was noted in both groups of examinees (r = -0.26, p = 0.27 in exposed group, r = -0.09, p=0.80 in controls). The data obtained also suggested an inverse correlation between necrosis and apoptosis (r = -0.37, p = 0.11 in exposed group, r = -0.89, p = 0.001 in controls). CONCLUSION: Flow cytometry being a rapid, fast, and accurate method is strongly recommended in evaluation of radiation injuries. The integration of apoptosis and necrosis into micronucleus assay could be very important in the assessment of cumulative effects of ionizing radiation in occupationally exposed medical personnel

The radioprotective properties of polyphenols on human lymphocytes

The aim of this study was to evaluate radioprotective properties of medical plants Gentianella austriaca and Gentianella dinarica. For this purpose human lymphocytes were irradiated using 60Co γ rays and treated with different fractions of plant extracts, afterwards micronuclei (MN) and malondialdehyde (MDA) were measured. Polyphenols, fractions isolated from those plants have shown the protective effects, seen as significantly reduced incidence of micronuclei which was followed with reduced level of malondialdehyde. The results obtained in this study indicate that polyphenols isolated from Gentianella austriaca and Gentianella dinarica posses radioprotective properties possibly trough reduction of the lipid peroxidation.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

Kinetics of adsorption of the bovine serum albumin on the silver nanoparticles

In this study, the kinetics of bovine serum albumin (BSA) adsorption from aqueous solutions on the methionine stabilized silver nanoparticles (AgNPs) was investigated. The influence of the parameters such as contact time and BSA initial concentration on the adsorption capacity of AgNPs were tested. By increasing the contact time up to 30 min, the percentage of adsorbed BSA was increased. After this time, no changes were observed, indicating that the equilibrium state was reached. Investigation of the initial concentration-effect showed that the percentage of BSA adsorption increased with increasing BSA concentration until the available binding sites were saturated. After that, more BSA molecules were left unadsorbed. To elucidate the adsorption kinetic, pseudo-first-order, pseudosecond-order, and intraparticle diffusion kinetic models were applied. The pseudo-second-order well described the adsorption process and intraparticle diffusion model rate laws, and the intraparticle diffusion is the sole rate-controlling step

The effect of flavonoid procyanidol on induction of micronuclei in human lymphocytes exposed to ionizing radiation in vitro

U radu je praćena promena učestalosti mikronukleusa u neozračenim i ozračenim kulturama humanih limfocita tretiranih (0,87µM i 4,37µM) procijanidolom. Učestalost mikronukleusa u uzorcima koji su tretirani 0,87µM pricijanidolom je ~40% manje u odnosu na učestalost mikronukleusa kontrolnih uzoraka, dok je u ozračenim uzorcima tretiranim 0,87µM procijanidolom, učestalosti mikronukleusa ~15% manje u odnosu na učestalost mikronukleusa ozračene kontrolne grupe. Ovako značajno smanjenje učestalisti mikronukleusa u uzorcima tretiranim 0,87µM procijanidolom potvrñuje njegov značajan protektivni efekat na kulture humanih limfocitaPhenolic components (procyanidols), common to red wine may be important in prevention of oxidative DNA damage. We have tested the hypothesis that the phenolic components of red wine are protective against the DNA-damaging by γ-radiation in vitro. The procyanidol (concentration, 87µM), added to unirradiated and irradiated samples, significantly reducted the yield of micronuclei, ~40% and ~15%, respectively. The study confirms strong radioprotective properties of procyanidols.XXIII Simpozijum Društva za zaštitu od zračenja Srbije i Crne Gore, Donji Milanovac, 26-28. septembar 2005

The antioxidants activity of flavonoids (procyanidol, quercetin, luteolin and kaempherol) in human lymphocytes exposed to ionizing radiation in vitro

U ovom radu je praćena promena učestalosti mikronukleusa(MN) i aktivnost antioksidativnih enzima katalaze(CAT) i glutation S transferaze (GST), kao i produkcija malondialdehida(MDA) u neozračenim i ozračenim ćelijskim kulturama humanih limfocita tretiranih 0,87μM flavonoidima (procijanidolom, kvercetinom, luteolinom i kemferolom). Rezultati su pokazali da najbolji antioksidativni efekat na ćelijske kulture humanih limfocita pokazuje procijanidol, antioksidativni efekat luteolina i kemferola je slabiji, dok kvercetin pokazuje i prooksidativnu aktivnost.Phenolic components (flavonoids), may be important in prevention of DNA damage. We have tested the hypothesis that the flavonoids are protective against the DNA-damaging by γ-radiation in vitro. The study confirms strong antioxidant activity and radioprotective properties of flavonoids.XXIV Simpozijum Društva za zaštitu od zračenja Srbije i Crne Gore, Zlatibor, 3-5. oktobar 2007

Repair kinetics of DSBs in human fibroblasts measured by γ-H2AX antibody

U radu su prikazani rezultati inherentne senzitivnosti i kinetika popravke dvolančanih prekida DNK lanca u fibroblastima kože, in vitro indukovanih ozračivanjem 60 Co-γ zračenjem, dozom 2Gy. Za kvantitativno odredjivanje broja dvolančanih prekida korišćena je imunofluorescentna metoda i monoklonsko antitelo na fosforilisani histon H, koja detktuje γ-H2AX fokuse u inetrfaznim jedrima. Dat je detaljan opis ove nove metode i prvi rezultati merenja kinetike repera.In this paper we present the results of intrinsic radiosenitivity and reapir kinetics of DSBs of human fibroblasts after irrdaiation with60 Co-γ rays, using dose of 2 Gy in vitro. Imunfluorescent method was used after hybridization with monoclonal antibody H2AX, which detects γ-H2AX foci as an early nucleolar formation to reapir DBSs. Detailed decsription of the method as wel as the first results of repair kinetics are disccused.XXIV Simpozijum Društva za zaštitu od zračenja Srbije i Crne Gore, Zlatibor, 3-5. oktobar 2007