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1.
J Environ Sci Health B ; 55(6): 583-591, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32238102

RESUMO

An original voltammetric screening method, employing glassy carbon electrode (GCE) with the differential-pulse voltammetry technique (DPV), has been developed to determine residues of the anti-parasitic agent Ronidazole (RNZ) in bovine meat. By using cyclic voltammetry (CV), it has been demonstrated that an irreversible cathodic process occurs at approximately -0.740 V (vs. Ag|AgCl, KCl 3 mol L-1) in a 0.100 mol L-1 phosphate buffer at pH 6.5 as supporting electrolyte. Furthermore, the behavior of RNZ in CV indicates the occurrence of a diffusion mass transfer process to the working electrode surface. The RNZ reduction mechanism was proposed as a 6-electron transfer, similar to Metronidazole under the same pH range. Quantification of RNZ and method validation were then carried out by DPV. The relative standard deviation (RSD) were 3.21% for intraday precision of 10 consecutive repetitions and 6.78% for interday precision after five analysis. Limits of detection and quantification were also obtained, and the values were 0.107 and 0.358 mg kg-1, respectively. The recovery percentage for three different concentrations of RNZ in the bovine meat matrix ranged between 98.1% and 100.3%. The method proved to be efficient for screening RNZ in bovine meat.


Assuntos
Eletroquímica/métodos , Análise de Alimentos/métodos , Carne Vermelha/análise , Ronidazole/análise , Animais , Carbono , Bovinos , Eletroquímica/instrumentação , Eletrodos , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Limite de Detecção , Reprodutibilidade dos Testes
2.
Chemosphere ; 238: 124579, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31434045

RESUMO

Nitroimidazoles are found in pharmaceuticals and personal care products (PPCPs) and, when discharged into the environment, have adverse effects on human health and survival. Advanced oxidation technologies (AOTs) based on persulfate (PS) can rapidly and efficiently degrade organic pollutants via strong oxidizing radicals under activation conditions. This study investigated the degradation of ronidazole (RNZ) by indirect electrolytic generation of PS and its activator, ferrous ion (Fe2+). An electrochemical system was developed, with a high concentration of PS generated at the anode while the activator Fe2+ was produced at the cathode. It showed that ammonium polyphosphate (APP) could effectively promote the electrolysis of PS. A high current efficiency (88%) at the anode could be obtained after 180 min at a high current density (300 mA cm-2). However, Fe2+ was inhibited at the cathode due to material control. The degradation of RNZ in the Fe2+/PS system generated from the electrochemical system was also explored. Increasing PS concentration and Fe2+/PS ratio were beneficial to the RNZ degradation. In homogeneous reactions, the degradation efficiency of RNZ could be improved by decreasing the Fe2+ addition rate through a peristaltic pump. Five intermediates were also detected and the degradation pathways were proposed. These findings provide a new method and mechanism for rapid and efficient degradation of RNZ.


Assuntos
Recuperação e Remediação Ambiental/métodos , Compostos Ferrosos/química , Ronidazole/metabolismo , Sulfatos/química , Poluentes Químicos da Água/análise , Técnicas Eletroquímicas , Eletrodos , Eletrólise , Ferro , Oxirredução
3.
Water Res ; 160: 296-303, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31154127

RESUMO

Ultraviolet light-emitting diodes (UV-LEDs) are promising alternatives to conventional low-pressure UV (LPUV) lamps, mainly because they contain no toxic mercury and have a potential for less energy consumption and longer lifetime. In this study, UV sources including UV-LEDs (265, 275 and 285 nm) and LPUV (254 nm) were compared in UV/chlorine degradation of an organic contaminant, ronidazole (RNZ). UV-LED/chlorine performed better than LPUV/chlorine at neutral and alkaline pH values for RNZ degradation considering the fluence-based rate constant. However, the wall plug efficiencies of UV-LEDs are relatively low at present and must reach about 20-25% to achieve the same electrical energy per order as the LPUV in UV/chlorine degradation of RNZ at pH 7.5 and 9. Neither the contribution of radical (HO· or Cl·) nor the quantum yield of chlorine could explain the different RNZ degradation rate by UV/chlorine at different wavelengths and pH values, while the chlorine photolysis rate should be the key factor for these phenomena. The effects of common co-existing substances in real water (chloride, bicarbonate and natural organic matter) on UV/chlorine degradation of RNZ were similar at different UV wavelengths. Opposite to other oxidants or reductants, the molar absorption coefficient of chlorine increases when the UV wavelength increases from 254 to 285 nm at neutral and alkaline pH, which makes UV-LED/chlorine one of the best choices for UV-LED-based advanced oxidation/reduction processes.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloro , Concentração de Íons de Hidrogênio , Oxirredução , Ronidazole , Raios Ultravioleta
4.
J AOAC Int ; 100(6): 1671-1680, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28707620

RESUMO

In this study, a simple, cost-effective, and sensitive HPLC diode-array detection method was developed for the simultaneous determination of six different 5-nitroimidazoles [metronidazole, 2-hydroxymethyl-1-methyl-5-nitro-1H-imidazole, dimetridazole (DMZ), ronidazole, ornidazole, and ipronidazole] in bovine milk samples. A QuEChERS-based sample preparation procedure was optimized by evaluating different cleanup sorbents, including zirconium-based sorbents (Z-Sep and Z-Sep+), C18, and primary-secondary amine (PSA), as well as EMR-Lipid cleanup solution. Acceptable analytical performance for all analytes was observed with recoveries in the range of 45-93% and RSDs of less than 15%. Negligible matrix interference was observed for most of the analytes due to application of PSA sorbent in a dispersive solid-phase extraction cleanup step. Method LOQs (mLOQs) for five of the six investigated analytes were set at a satisfactory low food product value of 2.5 ng/mL. For DMZ only, the mLOQ was set at 10 ng/mL. The procedure was evaluated through the analysis of 10 different natural samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Extração Líquido-Líquido/métodos , Leite/química , Nitroimidazóis/análise , Animais , Bovinos , Dimetridazol/análise , Contaminação de Alimentos/análise , Metronidazol/análise , Reprodutibilidade dos Testes , Ronidazole/análise , Sensibilidade e Especificidade , Manejo de Espécimes/métodos
5.
Inorg Chem ; 56(14): 7610-7614, 2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28665122

RESUMO

A water-stable 3D luminescent metal-organic framework (MOF), [Eu6Zn(µ3-OH)8(NDC)6(H2O)6]n (1), constructed from heterometallic [EuIII6ZnII] clusters and electron-rich π-conjugated 1,4-naphthalenedicarboxylic acid (H2NDC) ligands exhibits highly sensitive, selective, and reversible detection of ronidazole, which represents the first example of luminescent MOFs based on Ln-TM heterometallic clusters for the detection of antibiotics in aqueous solution.


Assuntos
Antibacterianos/análise , Európio/química , Substâncias Luminescentes/química , Estruturas Metalorgânicas/química , Ronidazole/análise , Zinco/química , Substâncias Luminescentes/síntese química , Estruturas Metalorgânicas/síntese química , Estrutura Molecular , Naftalenos/química , Água/química
6.
BMC Vet Res ; 13(1): 109, 2017 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-28412947

RESUMO

BACKGROUND: Tritrichomonas foetus is an emergent and important enteric pathogen of cats, which causes prolonged diarrhoea in cats. CASE PRESENTATION: This study describes a T. foetus infection in a seven-month-old, entire male domestic shorthair kitten with a six-month history of persistent large intestinal diarrhoea, faecal incontinence, prostration, apathy and weight loss. Parasites were microscopically observed and confirmed by PCR and DNA sequencing. Molecular analyses were carried out comparing the sequence obtained in this study with T. foetus and T. suis. Retrieved from GenBank. After treatment with ronidazole, the cat showed resolution of clinical signs. CONCLUSIONS: This is the first clinical case of T. foetus infection in a chronic diarrheic cat in Brazil and South America, confirming the presence of this pathogen in this part of the world and highlighting the importance of this protozoa being considered in the differential diagnosis of cats presenting diarrhoea of the large intestine. Our case report enriches our knowledge on the geographical distribution of T. foetus in cats in Brazil and provides further understanding of the clinical significance of feline intestinal trichomoniasis in this country.


Assuntos
Doenças do Gato/parasitologia , Diarreia/veterinária , Infecções Protozoárias em Animais/diagnóstico , Tritrichomonas foetus/isolamento & purificação , Animais , Antiprotozoários/administração & dosagem , Brasil/epidemiologia , Doenças do Gato/tratamento farmacológico , Gatos , DNA de Protozoário/análise , Diarreia/tratamento farmacológico , Diarreia/parasitologia , Masculino , Infecções Protozoárias em Animais/tratamento farmacológico , Ronidazole/administração & dosagem , Tritrichomonas foetus/genética
7.
J Feline Med Surg ; 19(3): 261-274, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28245739

RESUMO

Practical relevance: Trichomonosis of the large intestine of the cat was described as a cause of chronic diarrhea over 20 years ago. The trichomonad was identified as Tritrichomonas foetus, with a genotype that is distinct from venereal T foetus of cattle. Clinical challenges: Despite multiple means for diagnosis of the infection, including light microscopy, protozoal culture and PCR amplification using species-specific primers, tests with even greater sensitivity are needed. Feline trichomonosis is resistant to all commonly used antiprotozoal drugs. Ronidazole is currently the only drug demonstrated to be effective in eliminating the infection from cats; however, this drug has a narrow safety margin and clinical resistance is increasingly recognized. The more we learn about trichomonosis in cats, the more complicated and controversial the infection has become, ranging from what we should call the organism to whether we should even bother trying to treat it. Global importance: Feline trichomonosis is recognized to occur worldwide and is regarded as one of the most common infectious causes of colitis in the domestic cat. The infection is widespread in catteries and shelters; and, while remission of diarrhea may occur over time, persistence of the infection is common. Evidence base: This review provides a comprehensive examination of what is currently known about feline trichomonosis and pinpoints areas, based on the authors' opinion, where further research is needed.


Assuntos
Doenças do Gato/diagnóstico , Infecções Protozoárias em Animais/diagnóstico , Tritrichomonas foetus/isolamento & purificação , Animais , Antiprotozoários/uso terapêutico , Doenças do Gato/tratamento farmacológico , Doenças do Gato/parasitologia , Gatos , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/tratamento farmacológico , Infecções Protozoárias em Animais/parasitologia , Ronidazole/uso terapêutico , Tritrichomonas foetus/genética
8.
J Feline Med Surg ; 19(2): 177-184, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26662037

RESUMO

Objectives The aims of the study were to determine the in vitro drug release of guar gum-coated capsules of ronidazole, and to evaluate the pharmacokinetics and efficacy of this formulation for the treatment of cats naturally infected with Tritrichomonas foetus. Methods The pharmacokinetics of ronidazole were evaluated in five healthy cats and five cats infected with T foetus. In a second step, the clinical efficacy of these capsules was evaluated by a controlled, randomised, double-blind clinical trial performed in 47 infected cats from French catteries. In this study, cats were randomly allocated to either the ronidazole treatment group (n = 25) or a placebo group (n = 22). Ronidazole (30 mg/kg) q24h for 14 days was administered to the treated cats. After 14 days of treatment, the presence of T foetus was tested by conventional PCR assay. Results In the pharmacokinetic study, a delayed peak plasma concentration was observed in healthy and infected cats, with no significant difference between these two groups (mean geometric mean of 9 h for time to maximum plasma concentration [Tmax], 21.6 µg/ml for time to maximum plasma concentration [Cmax] and 467.4 µg/h/ml for the area under the curve [AUC] in healthy cats; and 9.4 h for Tmax, 17.1 µg/ml for Cmax and 481 µg/h/ml for AUC in infected cats). In the clinical trial, T foetus was detected in 16% of cats from the treated group and 82% of cats from the placebo group at the end of the study ( P <0.001). No clinical signs of adverse drug reactions were observed. Conclusions and relevance Oral administration of guar gum-coated capsules of ronidazole at a dose of 30 mg/kg once daily for 14 days delays the peak plasma concentration and eradicates infection in most cases.


Assuntos
Antiprotozoários/administração & dosagem , Doenças do Gato/tratamento farmacológico , Galactanos/administração & dosagem , Mananas/administração & dosagem , Gomas Vegetais/administração & dosagem , Infecções por Protozoários/tratamento farmacológico , Ronidazole/administração & dosagem , Tritrichomonas foetus , Administração Oral , Animais , Área Sob a Curva , Doenças do Gato/parasitologia , Gatos , Masculino
9.
Artigo em Inglês | MEDLINE | ID: mdl-27838954

RESUMO

Nitroimidazoles are not authorised for the treatment of honey bees in the European Union. However, they can be found in honey largely because they are illegally used in apiculture for the treatment of Nosema. The aim of the study was to examine the possible transfer of nitroimidazoles (metronidazole, ronidazole, dimetridazole and ipronidazole) from contaminated beeswax to honey. The wax foundations fortified with a mixture of four nitroimidazoles at three concentration levels (1000, 10,000 and 100,000 µg kg-1) were placed in beehives to let the honeybees (Apis mellifera L.) draw out the contaminated wax foundations to honeycombs. At 1 month from the start, the frames filled with capped honey were removed from the hives for a first sampling of honey. Next, the honeycombs were further incubated for 5 months in the laboratory at 35°C and sampled monthly. In the sampled honey, the concentrations of nitroimidazoles and their main metabolites (hydroxymetronidazole, 2-hydroxymethyl-1-methyl-5-nitroimidazole, hydroxyipronidazole) were determined by LC-MS/MS and compared with those determined in the nitroimidazole-containing wax foundations. Each of the tested nitroimidazoles could migrate from beeswax to honey kept in the contaminated combs at each tested concentration level. Higher maximum concentrations of residues in honey sampled from contaminated combs at 1000, 10,000 and 100,000 µg kg-1 were observed for metronidazole (28.9, 368.5 and 2589.4 µg kg-1 respectively) and ronidazole (27.4, 232.9 and 2351.2 µg kg-1 respectively), while lower maximum concentrations were measured for dimetridazole (0.98, 8.4 and 67.7 µg kg-1) and ipronidazole (0.9, 7.9 and 35.7 µg kg-1 respectively). When we took into account that a frame completely filled with honey on both sides of the comb contained 110 g of beeswax and 2488 g of honey, and that this ratio was constant, then maximum amounts of initial metronidazole, ronidazole, dimetridazole and ipronidazole that migrated from contaminated wax foundations to honey could be calculated: 65-89%, 55-63%, 1.7-2.7% and 1.4-2.3%, respectively.


Assuntos
Antifúngicos/análise , Contaminação de Alimentos/análise , Mel/análise , Drogas Veterinárias/análise , Ceras/química , Animais , Antifúngicos/administração & dosagem , Antifúngicos/metabolismo , Criação de Abelhas , Abelhas/efeitos dos fármacos , Abelhas/metabolismo , Transporte Biológico , Cromatografia Líquida , Difusão , Dimetridazol/administração & dosagem , Dimetridazol/análise , Dimetridazol/metabolismo , Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , União Europeia , Humanos , Ipronidazol/administração & dosagem , Ipronidazol/análise , Ipronidazol/metabolismo , Metronidazol/administração & dosagem , Metronidazol/análise , Metronidazol/metabolismo , Ronidazole/administração & dosagem , Ronidazole/análise , Ronidazole/metabolismo , Espectrometria de Massas em Tandem , Drogas Veterinárias/administração & dosagem , Drogas Veterinárias/metabolismo
10.
J Am Assoc Lab Anim Sci ; 55(4): 480-3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27423157

RESUMO

Tritrichomonas muris is occasionally identified during routine fecal screening of laboratory mice. Frequently, entire racks are affected, and because no effective treatment is available, culling of affected mice and rederivation by embryo transfer have been suggested. The current study evaluated whether treatment with ronidazole, a nitroimidazole efficacious against T. fetus infections in cats, combined with limited culling was effective against T. muris in laboratory mice (Mus musculus). A subset (n = 39) of mice were treated with ronidazole (400 mg/L in drinking water) for 15 d, after which 6 of the mice still shed T. muris. Consequently all mice in the affected rack received ronidazole (500 mg /L in drinking water) for 25 d. All mice were retested by using pooled samples, and those positive for T. muris (except for a valuable breeding pair) were culled. The remaining mice continued to receive ronidazole for another 17 d. At the end of the treatment period, all mice were tested (days 60 and 81) and were shown to be negative for T. muris. Over the following year, sentinel mice from the rack were tested every 3 mo and remained negative for tritrichomonads by fecal smear. Thus, a combination of limited culling and treatment with ronidazole in the drinking water successfully cleared research mice of infection with T. muris.


Assuntos
Antiprotozoários/administração & dosagem , Infecções Protozoárias em Animais/tratamento farmacológico , Infecções Protozoárias em Animais/prevenção & controle , Doenças dos Roedores/tratamento farmacológico , Doenças dos Roedores/prevenção & controle , Ronidazole/administração & dosagem , Tritrichomonas/efeitos dos fármacos , Animais , Erradicação de Doenças/métodos , Fezes/parasitologia , Camundongos , Infecções Protozoárias em Animais/parasitologia , Doenças dos Roedores/fisiopatologia , Resultado do Tratamento
11.
Int J Biol Macromol ; 85: 539-46, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26791585

RESUMO

Tritrichomonas foetus is a flagellated protozoan parasite that colonizes the feline colon causing colitis and chronic foul smelling diarrhoea. Despite the efficacy of Ronidazole in the treatment of T. foetus, Ronidazole has been reported to cause neurotoxicity in some cats due to rapid absorption in the small intestine. A novel amphoteric derivative of chitosan was synthesised and characterized. A combination of time, pH, and an enzyme controlled system was used in a study of a new compression coated tablet for delivery of Ronidazole to the colon. Axial, radial swelling and erosion of selected tablets were carried out in various media. The effect of weight ratio, enzyme and pH on in vitro drug release profile was investigated. The results show that less than 2% of the drug was released in the physiological environment of the stomach and small intestine.


Assuntos
Quitosana/química , Colo/efeitos dos fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Animais , Antiprotozoários/administração & dosagem , Linhagem Celular , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Ronidazole/administração & dosagem , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos/química , Temperatura , Difração de Raios X
12.
Berl Munch Tierarztl Wochenschr ; 128(9-10): 362-9, 2015.
Artigo em Alemão | MEDLINE | ID: mdl-26591381

RESUMO

Seven abyssinian cats (two male, five female) showed intermittent green-yellow mucous diarrhoea, sometimes an inflammation of the anal region and faecal incontinence even after long-time treatment with fenbendazole against Giardia. During necropsy of one of the cats, which had to be euthanized due to another disease, the gut wall of small and large intestine appeared macroscopically thickened. Histological examination indicated flagellates in the lumen of the intestine (initiating at the jejunum) and in the crypts. However Giardia could be excluded. in this case. By PCR of the faeces Tritrichomonas (T) foetus was diagnosed in five of six cats of this colony. Five remaining animals (another cat had to be euthanized) were treated with about 30 mg per kg BW ronidazole p. o. (rededication; Ridzol 10% Bt®, Dr. Hesse Tierpharma GmbH & Co. KG, Germany) daily over 14 days. The special gastro-resistant processing of the ronidazole should ensure a targeted effects. Animals were treated consecutively, isolated from the other cats and were daily examined clinically and neurologically. Neurotoxic adverse effects appeared slightly, therefore--as a precaution--the treatment of two cats was paused for one day. After treatment of all cats, T. foetus wasn't diagnosed by PCR over the period of 345 to > 800 days in any cat. One animal had dubious findings in the ninth week after treatment. Hence it was still kept isolated from the group and PCR showed a negative result at all times afterwards. The treatment protocol shows that elimination of problematic protozoal infections is possible in cat colonies.


Assuntos
Antiprotozoários/administração & dosagem , Doenças do Gato/tratamento farmacológico , Intestino Delgado/metabolismo , Infecções Protozoárias em Animais/tratamento farmacológico , Ronidazole/administração & dosagem , Tritrichomonas foetus , Administração Oral , Animais , Antiprotozoários/farmacocinética , Doenças do Gato/metabolismo , Gatos , Preparações de Ação Retardada , Feminino , Absorção Intestinal , Masculino , Infecções Protozoárias em Animais/metabolismo , Ronidazole/farmacocinética , Comprimidos
13.
Artigo em Inglês | MEDLINE | ID: mdl-25372355

RESUMO

The depletion of three banned nitroimidazole drugs - dimetridazole (DMZ), metronidazole (MNZ) and ronidazole (RNZ) - was investigated in black tiger shrimp (Penaeus monodon) following in-water medication. The highest concentrations of residues were measured immediately after the 24-h immersion (d0). At this time, MNZ and MNZ-OH residues were measured in shrimp tissue samples at concentrations ranging from 361 to 4189 and from 0.28 to 6.6 µg kg(-1), respectively. DMZ and its metabolites HMMNI ranged in concentration between 31,509 and 37,780 and between 15.0 and 31.9 µg kg(-1), respectively. RNZ and HMMNI concentrations ranged from 14,530 to 24,206 and from 25.0 to 55 µg kg(-1), respectively. MNZ, DMZ and RNZ were the more persistent marker residues and can be detected for at least 8 days post-treatment. MNZ-OH was only detectable on d0 following treatment with MNZ. HMMNI residues were only detectable up to d1 (0.97-3.2 µg kg(-1)) or d2 (1.2-4.5 µg kg(-1)) following DMZ and RNZ treatment, respectively. The parent drugs MNZ, DMZ and RNZ were still measureable on d8 at 0.12-1.0, 40.5-55 and 8.8-18.7 µg kg(-1), respectively. The study also investigated the stability of nitroimidazole residues under various cooking procedures (frying, grilling, boiling, and boiling followed by microwaving). The experiments were carried out in shrimp muscle tissue containing both high and low concentrations of these residues. Different cooking procedures showed the impact on nitroimidazole residue concentration in shrimp tissue. Residue concentration depleted significantly, but partially, by boiling and/or microwaving, but the compounds were largely resistant to conventional grilling or frying. Cooking cannot therefore be considered as a safeguard against harmful nitroimidazole residues in shrimp.


Assuntos
Culinária , Dimetridazol/análise , Aditivos Alimentares/análise , Análise de Alimentos , Metronidazol/análise , Penaeidae/química , Ronidazole/análise , Animais
14.
Water Res ; 65: 271-81, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25141357

RESUMO

Degradation kinetics and pathways of ronidazole (RNZ) by chlorination (Cl2), UV irradiation and combined UV/chlorine processes were investigated in this paper. The degradation kinetics of RNZ chlorination followed a second-order behavior with the rate constants calculated as (2.13 ± 0.15) × 10(2) M(-2) s(-1), (0.82 ± 0.52) × 10(-2) M(-1) s(-1) and (2.06 ± 0.09) × 10(-1) M(-1) s(-1) for the acid-catalyzed reaction, as well as the reactions of RNZ with HOCl and OCl(-), respectively. Although UV irradiation degraded RNZ more effectively than chlorination did, very low quantum yield of RNZ at 254 nm was obtained as 1.02 × 10(-3) mol E(-1). RNZ could be efficiently degraded and mineralized in the UV/chlorine process due to the generation of hydroxyl radicals. The second-order rate constant between RNZ and hydroxyl radical was determined as (2.92 ± 0.05) × 10(9) M(-1) s(-1). The degradation intermediates of RNZ during the three processes were identified with Ultra Performance Liquid Chromatography - Electrospray Ionization - mass spectrometry and the degradation pathways were then proposed. Moreover, the variation of chloropicrin (TCNM) and chloroform (CF) formation after the three processes were further evaluated. Enhanced formation of CF and TCNM precursors during UV/chlorine process deserves extensive attention in drinking water treatment.


Assuntos
Cloro/química , Ronidazole/química , Raios Ultravioleta , Poluentes Químicos da Água/química , Purificação da Água/métodos , Clorofórmio/química , Halogenação , Hidrocarbonetos Clorados/química , Cinética
15.
Talanta ; 128: 293-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25059163

RESUMO

In this study, the surface enhanced Raman spectra (SERS) of two prohibited veterinary drugs, metronidazole (MNZ) and ronidazole (RNZ), have been acquired, and compared to the theoretically calculated spectra using density function theory (DFT). The experimental Raman and SERS spectra of MNZ and RNZ exhibit high resemblance with the DFT calculations. SERS detection of MNZ and RNZ from standard solutions as well as real environmental samples (tap, lake, swamp waters and soil) was performed on highly sensitive and reproducible silver nanorod array substrates. The limits of detection for MNZ and RNZ are 10 and 1 µg/mL in methanol and ultra-pure water, respectively, and 10-50 µg/mL in the environmental samples. The SERS-based method demonstrates its potential as a rapid, simple, and inexpensive means for the onsite screening of banned antibiotics from the aquatic and sediment environments, with minimal requirement for sample pretreatment.


Assuntos
Metronidazol/análise , Ronidazole/análise , Solo/química , Análise Espectral Raman/métodos , Recursos Hídricos/análise , Análise Discriminante , Água Potável/análise , Água Potável/química , Monitoramento Ambiental/métodos , Água Doce/análise , Água Doce/química , Lagos/química , Análise dos Mínimos Quadrados , Análise de Componente Principal , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Abastecimento de Água/análise
16.
Meat Sci ; 97(2): 214-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24583330

RESUMO

In contrast with the information of the inspection body concerning the use of ronidazole, several non compliant muscle samples were detected using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method in accordance with confirmation criteria of Decision 2002/657/EC. This led to the suspicion that non compliance could be due to false positive results. In this context, a liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed and sample extracts were re-analyzed, resolving the co eluting isobaric interfering peak, which also has an interfering product ion with the transition product (m/z 201>140).


Assuntos
Anti-Infecciosos/análise , Contaminação de Alimentos/análise , Carne/análise , Músculos/química , Ronidazole/análise , Cromatografia Líquida/métodos , Humanos , Íons , Espectrometria de Massas em Tandem/métodos
17.
J Feline Med Surg ; 15(12): 1098-103, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23838083

RESUMO

The clinical presentation and response to treatment of cats infected with Tritrichomonas foetus have not been sufficiently described in a large number of pet cats. The aim of this study was to collect and analyze clinical data from pet cats diagnosed with intestinal T foetus infection. Clinical information was collected for 104 cats that tested polymerase chain reaction-positive for T foetus. The most common clinical sign was diarrhea (98%) with a median duration of 135 days (range 1-2880 days). Forty-nine of 83 (59%) cats had diarrhea since adoption. Other clinical signs included anorexia (22%), depression (24%), weight loss or failure to gain weight (20%), vomiting (19%), abdominal pain (9%) and increased appetite (3%). A total of 45 cats had completed treatment with ronidazole, 29 of which (64%) showed a good clinical response to treatment. Sixteen (36%) cats had either partial or no improvement, or a relapse shortly after discontinuation of treatment.


Assuntos
Doenças do Gato/parasitologia , Enteropatias Parasitárias/veterinária , Infecções Protozoárias em Animais/parasitologia , Tritrichomonas foetus/isolamento & purificação , Envelhecimento , Animais , Antiprotozoários/uso terapêutico , Gatos , Fezes , Enteropatias Parasitárias/parasitologia , Estudos Retrospectivos , Ronidazole/uso terapêutico , Inquéritos e Questionários
18.
J Vet Pharmacol Ther ; 36(4): 399-407, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23106427

RESUMO

Ronidazole (RDZ) is the only known effective treatment for feline diarrhea caused by Tritrichomonas foetus. This study aimed to develop guar gum-coated colon-targeted tablets of RDZ and to determine the pharmacokinetics of this delayed-release formulation in cats. Guar gum-coated tablets were administered orally once to five healthy cats (mean dose 32.3 mg/kg). The tablets were then administered once daily for 5 days to four cats (mean dose 34.5 mg/kg), and absorption studies repeated on day 5. Plasma was collected and analyzed for RDZ concentration, and pharmacokinetic noncompartmental and deconvolution analysis were performed on the data. There was negligible RDZ release until after 6 h, and a delayed peak plasma concentration (mean Cmax 28.9 µg/mL) at approximately 14.5 h, which coincides with colonic arrival in cats. Maximum input rate (mg/kg per hour) occurred between 6 and 16 h. This delayed release of ronidazole from guar gum-coated tablets indicates that release of RDZ may be delayed to deliver the medication to a targeted area of the intestine. Repeated dosing with guar gum tablets to steady-state did not inhibit drug bioavailability or alter the pharmacokinetics. Such targeted RDZ drug delivery may provide improved efficacy and reduce adverse effects in cats.


Assuntos
Antiprotozoários/farmacocinética , Gatos/metabolismo , Galactanos/química , Mananas/química , Gomas Vegetais/química , Ronidazole/farmacocinética , Animais , Antiprotozoários/administração & dosagem , Antiprotozoários/sangue , Área Sob a Curva , Gatos/sangue , Preparações de Ação Retardada , Meia-Vida , Masculino , Ronidazole/administração & dosagem , Ronidazole/sangue , Comprimidos
19.
Korean J Parasitol ; 50(2): 161-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22711930

RESUMO

To evaluate the efficacy of ronidazole for treatment of Tritrichomonas foetus infection, 6 Tritrichomonas-free kittens were experimentally infected with a Korean isolate of T. foetus. The experimental infection was confirmed by direct microscopy, culture, and single-tube nested PCR, and all cats demonstrated trophozoites of T. foetus by day 20 post-infection in the feces. From day 30 after the experimentally induced infection, 3 cats were treated with ronidazole (50 mg/kg twice a day for 14 days) and 3 other cats received placebo. Feces from each cat were tested for the presence of T. foetus by direct smear and culture of rectal swab samples using modified Diamond's medium once a week for 4 weeks. To confirm the culture results, the presence of T. foetus rRNA gene was determined by single-tube nested PCR assay. All 3 cats in the treatment group receiving ronidazole showed negative results for T. foetus infection during 2 weeks of treatment and 4 weeks follow-up by all detection methods used in this study. In contrast, rectal swab samples from cats in the control group were positive for T. foetus continuously throughout the study. The present study indicates that ronidazole is also effective to treat cats infected experimentally with a Korean isolate of T. foetus at a dose of 50 mg/kg twice a day for 14 days.


Assuntos
Antiprotozoários/administração & dosagem , Doenças do Gato/tratamento farmacológico , Infecções por Protozoários/tratamento farmacológico , Ronidazole/administração & dosagem , Tritrichomonas foetus/patogenicidade , Animais , Doenças do Gato/parasitologia , Gatos , Modelos Animais de Doenças , Fezes/parasitologia , Masculino , Parasitologia/métodos , Placebos/administração & dosagem , Reação em Cadeia da Polimerase/métodos , Infecções por Protozoários/parasitologia , Resultado do Tratamento , Tritrichomonas foetus/genética , Tritrichomonas foetus/isolamento & purificação
20.
J Pharm Biomed Anal ; 64-65: 40-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22417613

RESUMO

A rapid liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to identify and to quantify nitroimidazoles, metronidazole (MNZ), ronidazole (RNZ) and dimetridazole (DMZ) and their corresponding hydroxy metabolites, MNZ-OH and 2-hydroxymethyl-1-methyl-5-nitroimidazole (HMNNI) in plasma, milk, muscle, egg, honey and feed samples. The same sample clean-up procedure including a novel solid-phase extraction (SPE) on polymeric Strata-SDB cartridges was used for each matrix. The analytes were separated on Kinetex XB C-18 core-shell type HPLC column using isocratic elution mode with a mobile phase containing 0.1% formic acid in water/methanol (88/12, v/v, pH 2.6) at a flow rate of 0.7 ml/min. The main advantage of the developed method is that the analysis time of only 3 min, which is about three to ten times shorter than in other reported HPLC methods. The developed method was validated using a matrix-comprehensive in-house validation strategy. The matrix effect of LC-MS/MS analysis was also investigated. Results are presented from the successful application of the developed method to an incurred pork meat certified reference material and to incur porcine plasmas in a proficiency test in year 2011.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dimetridazol/análise , Resíduos de Drogas/análise , Metronidazol/análise , Ronidazole/análise , Espectrometria de Massas em Tandem/métodos , Ração Animal/análise , Animais , Dimetridazol/análogos & derivados , Dimetridazol/sangue , Dimetridazol/química , Ovos/análise , Mel/análise , Carne/análise , Metronidazol/análogos & derivados , Metronidazol/sangue , Metronidazol/química , Leite/química , Estrutura Molecular , Músculos/química , Plasma/química , Ronidazole/análogos & derivados , Ronidazole/sangue , Ronidazole/química , Suínos , Fatores de Tempo
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