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1.
Helminthologia ; 58(2): 173-178, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34248377

RESUMEN

Cases of parasite resistance to the main classes of anthelmintics are increasingly reported from small ruminants at farms in Europe. We visited a goat farm in Slovakia in November 2019 with suspected parasite problems that reduced productivity and performed an in vivo faecal egg count reduction test (FECRT) and an in vitro larval development test (LDT) for all three main classes of anthelmintics. The lowest efficacy (60 %) detected by FECRT was for ivermectin (IVM). Benzimidazole (BZ) efficacy ranged between 80.3 and 86.5 %, and levamisole (LEV) efficacy was 94 %. The results from the in vivo FECRT test were confirmed by the in vitro LDT. Minimum inhibitory concentration (MIC) 173.6 ng/ml for IVM several times exceeded the recommended threshold of 21.6 ng/ml. Mean LD50 for BZ was equal to the threshold concentration, but the other threshold criteria indicated a low level of resistance in the population. The LDT did not indicate the presence of resistance only for LEV. The MIC 1.0 µg/ml for LEV was evaluated as susceptible with respect to species composition. Teladorsagia was the dominant genus after treatment with BZ, IVM, and LEV. Haemonchus contortus was identifi ed after treatment with BZ and LEV.

2.
Helminthologia ; 56(4): 303-309, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31708670

RESUMEN

Our study describes changes in haematological parameters in wild ruminants with parasitic infection. Six European mouflons (Ovis musimon), six fallow deer (Dama dama) and six roe deer (Capreolus capreolus) were experimentally infected with the resistant strain of the model parasite 8000 L3 Haemonchus contortus. The blood samples were collected on Day 0, 16, 37, 58, 77, and 99 of the experiment. Mild anaemia was observed in mouflons and roe deer while red blood cells increased in red blood counts (total erythrocytes, haematocrit and haemoglobin). As for the white blood cells count, leucopenia with neutrophilia and lymphopenia was recorded in mouflons, in the fallow deer and roe deer leucocytosis with neutropenia and lymphocytosis were observed. Changes in the dynamics of haematological parameters were statistically insignificant.

3.
Vet Parasitol ; 254: 10-14, 2018 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-29656993

RESUMEN

Anthelmintic resistance (AR) is a serious threat to animal health and has a major economic impact worldwide due to production and financial losses. The aim of this study was to determine the occurrence of AR on 30 goat farms in Slovakia during the pasturing seasons and to compare three widely used in vitro and in vivo methods for detecting AR in field conditions. A three-year survey was conducted during the pasturing seasons of 2014-2016. Goats on each farm were split into treated and control groups and were treated by recommended (5 mg/kg body weight) and double doses (10 mg/kg b.w.) of albendazole. Comparisons between percent reduction in a faecal egg count reduction test (FECRT) and an egg hatch test (EHT) and the presence of L3 larvae in a larval development test (LDT) using resistant concentrations of benzimidazole (BZ) were monitored after treatment. The FECRT indicated percent reductions of 69.2-86.2% for the single dose and of 36.3-45.4% for the double dose. The EHT indicated that all farms had BZ-resistant nematodes. Low (<15% hatching) and high (>15% hatching) levels of resistance were detected on 13 and 17 farms, respectively. The LDT failed to detect resistant larvae on seven farms but detected low and high levels of resistance on seven and 14 farms, respectively. The data indicate a moderate correlation between in vitro and in vivo tests for detecting BZ resistance among the 30 goat farms. The hatching detected by the EHT and the presence of L3 larvae by the LDT at resistant BZ concentrations provided reasonable identification of low levels of resistance in the parasite populations, but the use of a double dose for a treatment may underestimate the real occurrence of low levels of resistant parasites on goat farms.


Asunto(s)
Antihelmínticos/farmacología , Bencimidazoles/farmacología , Resistencia a Medicamentos , Haemonchus/efectos de los fármacos , Ostertagia/efectos de los fármacos , Trichostrongylus/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Cabras/parasitología , Haemonchus/anatomía & histología , Haemonchus/crecimiento & desarrollo , Técnicas In Vitro , Larva/anatomía & histología , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Ostertagia/anatomía & histología , Ostertagia/crecimiento & desarrollo , Eslovaquia , Trichostrongylus/anatomía & histología , Trichostrongylus/crecimiento & desarrollo
4.
J Pharm Biomed Anal ; 29(6): 1153-7, 2002 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12110402

RESUMEN

The impurity profile of ethynodiol diacetate was investigated using the HPLC/UV/MS method. Using the slightly modified HPLC method of USP 24 two impurities, earlier isolated by preparative HPLC and investigated by NMR spectroscopy were separated and characterised. The mass spectra amended by the diode-array UV spectra supported the earlier found structures (E and Z isomers of 17alpha-ethinyl-estr-4-ene-3beta,17-diol-3-acetate-17-(3'-acetoxy-2'-butenoate). Another, hitherto not described impurity, 17alpha-ethinyl-estr-4-ene-3beta,17-diol-3-acetate-17-(3-oxo-butanoate) has also been separated and characterised by means of its mass spectrum, NMR and UV spectra.


Asunto(s)
Anticonceptivos Sintéticos Orales/análisis , Contaminación de Medicamentos , Diacetato de Etinodiol/análisis , Preparaciones Farmacéuticas/normas , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Espectrofotometría Ultravioleta , Estereoisomerismo
5.
Acta Pharm Hung ; 69(2): 60-8, 1999 Apr.
Artículo en Húngaro | MEDLINE | ID: mdl-10389299

RESUMEN

It has been investigated if UV-VIS spectroscopy and spectrophotometry can be regarded to be obsolete methods in pharmaceutical analysis. The conclusions are as follows. As a consequence of the introduction and spreading of highly efficient spectroscopic methods in the structural analysis of organic compounds the importance of UV-VIS spectroscopy as a structure elucidation tool has greatly decreased. At the same time, however, diode-array UV spectrophotometers used as HPLC detectors have created very convenient possibilities for the identification of minor components (impurities, degradation products, etc.) in drugs. This statement is illustrated by several practical examples. On the basis of some data taken from the British Pharmacopoeia 1998 it is stated that UV spectrophotometry as a quantitative analytical method still belongs to the most frequently used analytical techniques in pharmaceutical analysis. At the same time, however, the authors are of negative opinion about the up-to-dateness and usefulness of colorimetric methods still very often published for the determination of drug substances.


Asunto(s)
Farmacia/métodos , Espectrofotometría/métodos , Colorimetría/métodos , Estructura Molecular , Farmacopeas como Asunto , Espectrofotometría Ultravioleta/métodos , Reino Unido
6.
J Pharm Biomed Anal ; 17(6-7): 1029-36, 1998 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-9884192

RESUMEN

Reversed-phase HPLC methods using C-18 and C-8 columns as well as various isocratic and gradient systems with aqueous ammonium acetate, methanol and acetonitrile are described for the separation of the impurities of mazipredone (11beta,17-dihydroxy-21-(4-methyl-1-piperazinyl)-pregna-1,4-diene- 3,20-dione hydrochloride). These methods were used also for the estimation of the hydrolytic and oxidative degradation pathways of mazipredone in 0.1 M hydrochloric acid and sodium hydroxide at 80 degrees C. With the aid of HPLC-(APCI)-MS and HPLC-diode-array UV techniques 15 impurities and degradation products have been identified.


Asunto(s)
Técnicas de Química Analítica/métodos , Contaminación de Medicamentos , Prednisolona/análogos & derivados , Cromatografía Líquida de Alta Presión , Concentración de Iones de Hidrógeno , Espectrometría de Masas , Estructura Molecular , Prednisolona/química , Prednisolona/metabolismo
7.
J Pharm Biomed Anal ; 18(4-5): 511-25, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9919951

RESUMEN

Due to the varied reactions leading to the 3-oxo group in steroids and the reactivity of its environment, a large number of impurities related to this group are formed during the reaction steps and the degradation studies. In this paper the experiences from the authors laboratory with the 3-oxo-related impurities in 19-nor-4-ene-3-oxosteroids (norgestrel, norethisterone, nandrolone, its esters and Nestorone) as well as corticosteroids (prednisolone, mazipredone, etc) are presented. The impurities include saturated 3-ones, 1-ene-3-ones, 5(10)-ene-3-ones, 3-deoxo and 3-ethinyl-3,5-diene derivatives, 6-ene, 8(14)-ene, 6,8(14)-diene, 6-hydroxy (alpha and beta), 10beta-hydroxy and 6-one derivatives in 4-ene-3-oxosteroids and 8(9)-ene, 9(11)-ene, 11alpha-hydroxy, 11-oxo and 4-ene-3-one derivatives in 11beta-hydroxy-1,4-diene-3-oxosteroids. The chromatographic, spectroscopic and hyphenated techniques used in this study include TLC, GC, HPLC with diode array UV detector, GC-MS, LC-MS and NMR methods.


Asunto(s)
Contaminación de Medicamentos , Cetosteroides/química , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Modelos Químicos , Espectrofotometría Ultravioleta
8.
Talanta ; 44(9): 1517-26, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18966892

RESUMEN

A general scheme is set up for the estimation of the impurity profile of bulk drug substances by the complex use of chromatographic, spectroscopic and hyphenated techniques. Several examples are presented as illustrations to the scheme from the authors' laboratory involving the use of chromatographic methods such as thin-layer-(TLC), gas-(GC), analytical and preparative high-performance liquid chromatography (HPLC), spectroscopic methods such as mass spectrometry (MS) and NMR spectroscopy as well as hyphenated techniques (HPLC/diode-array UV, GC/MS and HPLC/MS). In addition to summarizing earlier work, new examples are also presented: identification of an impurity (propyl 4-[diethylcarbamoyl(methoxy)]-3-methoxy phenylglyoxylate, II) in propanidid (I) and two unsaturated impurities in allylstrenol (VII) by GC/MS and HPLC/diode-array UV as well as estimation of the impurity profile of mazipredone (III) by HPLC/MS and HPLC/diode-array UV.

9.
Am Heart J ; 131(1): 81-8, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8554024

RESUMEN

The objective of this investigation was the examination of the relation of left ventricular mass (LVM) and function with cardiovascular response to exercise in normotensive adolescents at risk for hypertension. Carried out was a prospective, cross-sectional study of 47 subjects (age, 10 to 18 years), who underwent dynamic and isometric exercise, 24-hour Holter monitoring, and echocardiography. Twenty-nine had normotensive parents (group 2, "at risk"). Both groups were similar for age, race, sex, body mass index, blood pressures, and resting heart rates. Group 2 had a higher E/A ratio (2.3 +/- 0.5 vs 2.0 +/- 0.5; p = 0.039) and higher heart rates during stage IV of dynamic exercise (188 +/- 20 beats/min vs 176 +/- 18 beats/min; p = 0.046). The LVM, 24-hour heart rates, and exercise systolic blood pressures (SBP) were similar in both groups. Only in group 2, SBP at peak dynamic and isometric exercise correlated best with LVM (r = 0.74, p < 0.002; r = 0.82, p < 0.001). It is concluded that altered hemodynamic regulatory mechanisms may exist before the establishment of hypertension in normotensive subjects with parental hypertension.


Asunto(s)
Corazón/fisiología , Hipertensión/genética , Adolescente , Presión Sanguínea , Niño , Estudios Transversales , Ecocardiografía , Ecocardiografía Doppler , Electrocardiografía Ambulatoria , Ejercicio Físico , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca , Ventrículos Cardíacos , Humanos , Hipertensión/fisiopatología , Masculino , Padres , Esfuerzo Físico/fisiología , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Función Ventricular Izquierda
10.
J Chromatogr ; 550(1-2): 639-44, 1991 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-1663506

RESUMEN

A normal-phase ion-pair chromatographic system has been developed for the high-performance liquid chromatographic investigation of pipecuronium bromide (2 beta,16 beta-bis-(N'-dimethyl-l-piperazinyl)-3 alpha,17 beta-diacetoxy-5 alpha-androstane dibromide) and related quaternary ammonium steroids. The use of silica as the stationary phase and a 96:4 mixture of acetonitrile and water containing 0.1 mol/dm3 sodium perchlorate as the eluent with detection at 213 nm enable the potential impurities as well as the hydrolytic and oxidative degradation products of pipecuronium bromide to be separated and detected down to the 0.01% level. The above system is also applicable to the high-performance liquid chromatographic investigation of other quaternary ammonium steroids (pancuronium bromide, vecuronium bromide).


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Compuestos de Amonio Cuaternario/análisis , Dióxido de Silicio , Compuestos de Sodio , Esteroides/análisis , Percloratos
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