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1.
Schweiz Arch Tierheilkd ; 159(8): 437-444, 2017 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-28791950

RESUMO

INTRODUCTION: The interest in equine dentistry has significantly increased in the last 15 years. On the part of the veterinarians as well as of the horse owners there is a strong attention to the topic. The aim of the questionnaire was to investigate amongst horse owners what their level of information and preferences about dental treatment are and how they are implemented. The questionnaire was translated into the three national languages and included 20 questions about level and sources of information, frequency of treatments and the horse owner's stance over sedation of the animals. With a return rate of 45% (1'466 of 3'250 sent questionnaires) significant conclusions could be drawn. Horse owners showed a strong demand for clarification regarding tooth problems, the causes, consequences and methods of treatment. More than half of the owners considered themselves not well informed. The treating person was in 66.7% a veterinarian with a special education. Horse owners indicated that information circulated most frequently by word of mouth recommendations and they explicitly wished information from professional and reliable sources. The questionnaire provided a clear result about current equine dental treatments. We suggest that they should be performed by veterinarians only with a special education.


INTRODUCTION: Au cours des 15 dernières années, l'intérêt pour la médecine dentaire chez les chevaux a de nouveau beaucoup augmenté. Tant les vétérinaires que les propriétaires de chevaux accordent une grande importance à ce sujet. Le but de la présente enquête était de juger le niveau d'information et des préférences en matière de soins dentaires parmi les propriétaires en Suisse et comment elles se concrétisent. Le questionnaire a été rédigé dans les trois langues nationales et comportait 20 questions relatives au niveau et aux sources d'information des propriétaires ainsi qu'à la fréquence des soins dentaires et à la position des propriétaires face à la sédation de leur animal. Avec un taux de retour de 45% (1'466 sur 3'250 questionnaires envoyés), il a été possible de tirer des conclusions significatives. Les propriétaires de chevaux montrent un net besoin en matière d'explication concernant les problèmes dentaires, leurs causes, leurs conséquences et leurs méthodes de traitement. Plus de la moitié se considèrent comme insuffisamment informés. Chez 66.7%, le traitement est effectué par un vétérinaire spécialisé en soins dentaires. Les propriétaires déclarent que les informations leur sont le plus souvent fournies oralement et souhaitent clairement des informations de sources professionnelles et fiables. L'enquête a fourni des données claires sur les soins dentaires actuels chez le cheval. Il en résulte que nous recommandons que ces soins soient effectués principalement par des vétérinaires spécialisés sur ce domaine.


Assuntos
Odontologia/métodos , Medicina Veterinária/métodos , Animais , Odontologia/normas , Cavalos , Inquéritos e Questionários , Suíça , Medicina Veterinária/normas
2.
Forensic Toxicol ; 42(2): 248-254, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38704758

RESUMO

PURPOSE: Inadvertent and/or unknowing exposure to drugs and drug residues has been frequently debated in situations of so-called adverse analytical finding (AAF) in the context of sports drug testing programs. Transfer of drug residues via unprotected intercourse is a conceivable scenario but scientific data and authentic case reports are scarce. Herein, investigations into two AAFs with the peroxisome proliferator-activated receptor delta (PPARδ) agonist GW1516 are reported and discussed. METHODS: To probe for a contamination scenario involving sexual intercourse, two assays were used to determine semenogelin in human urine, with one employing an immunochromatographic lateral flow approach and another based on liquid chromatography-tandem mass spectrometry. Further, drug-residue testing using patients' ejaculate was conducted by utilizing liquid chromatography in conjunction with a triple quadrupole mass spectrometer, followed by re-analysis of suspect samples (i.e., samples indicating the presence of relevant compounds) using high resolution/high mass accuracy mass spectrometry. RESULTS: In one case, but not the other, the possibility of intimate contact as the source of the AAF was confirmed after a thorough investigation of potential contamination scenarios. Subsequent research revealed analytical evidence for the presence of seminal fluid in one of the female athlete's doping control urine samples, and the analysis of clinical ejaculate specimens provided first data on an authentic concentration level of GW1516 and its metabolites in human seminal fluid. CONCLUSIONS: The combined facts substantiate the possibility of an AAF caused by unprotected sexual intercourse and the plausibility of the case-related arguments.


Assuntos
Dopagem Esportivo , Sêmen , Espectrometria de Massas em Tandem , Tiazóis , Humanos , Dopagem Esportivo/prevenção & controle , Feminino , Sêmen/química , Sêmen/metabolismo , Masculino , Cromatografia Líquida/métodos , Adulto , Detecção do Abuso de Substâncias/métodos , Cromatografia de Afinidade/métodos
3.
Anal Bioanal Chem ; 405(25): 8285-94, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23877183

RESUMO

The discovery and implementation of the long-term metabolite of metandienone, namely 17ß-hydroxymethyl-17α-methyl-18-norandrost-1,4,13-trien-3-one, to doping control resulted in hundreds of positive metandienone findings worldwide and impressively demonstrated that prolonged detection periods significantly increase the effectiveness of sports drug testing. For oxandrolone and other 17-methyl steroids, analogs of this metabolite have already been described, but comprehensive characterization and pharmacokinetic data are still missing. In this report, the synthesis of the two epimeric oxandrolone metabolites-17ß-hydroxymethyl-17α-methyl-18-nor-2-oxa-5α-androsta-13-en-3-one and 17α-hydroxymethyl-17ß-methyl-18-nor-2-oxa-5α-androsta-13-en-3-one-using a fungus (Cunninghamella elegans) based protocol is presented. The reference material was fully characterized by liquid chromatography nuclear magnetic resonance spectroscopy and high resolution/high accuracy mass spectrometry. To ensure a specific and sensitive detection in athlete's urine, different analytical approaches were followed, such as liquid chromatography-tandem mass spectrometry (QqQ and Q-Orbitrap) and gas chromatography-tandem mass spectrometry, in order to detect and identify the new target analytes. The applied methods have demonstrated good specificity and no significant matrix interferences. Linearity (R(2) > 0.99) was tested, and precise results were obtained for the detection of the analytes (coefficient of variation <20%). Limits of detection (S/N) for confirmatory and screening analysis were estimated at 1 and 2 ng/mL of urine, respectively. The assay was applied to oxandrolone post-administration samples to obtain data on the excretion of the different oxandrolone metabolites. The studied specimens demonstrated significantly longer detection periods (up to 18 days) for the new oxandrolone metabolites compared to commonly targeted metabolites such as epioxandrolone or 18-nor-oxandrolone, presenting a promising approach to improve the fight against doping.


Assuntos
Anabolizantes/metabolismo , Anabolizantes/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Oxandrolona/metabolismo , Oxandrolona/urina , Detecção do Abuso de Substâncias/métodos , Anabolizantes/síntese química , Anabolizantes/química , Cromatografia Líquida/métodos , Dopagem Esportivo , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Oxandrolona/análogos & derivados , Oxandrolona/síntese química , Espectrometria de Massas em Tandem/métodos
4.
Anal Bioanal Chem ; 401(2): 517-28, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21188579

RESUMO

Methods of blood doping such as autologous and homologous blood transfusion are one of the main challenging doping practices in competitive sport. Whereas homologous blood transfusion is detectable via minor blood antigens, the detection of autologous blood transfusion is still not feasible. A promising approach to indicate homologous or autologous blood transfusion is the quantification of increased urinary levels of di(2-ethylhexyl) phthalate (DEHP) metabolites found after blood transfusion. The commonly used plasticizer for flexible PVC products, such as blood bags, is DEHP which is known to diffuse into the stored blood. Therefore, a straight forward, rapid and reliable assay is presented for the quantification of the main metabolites mono(2-ethyl-5-oxohexyl) phthalate, mono(2-ethyl-5-hydroxyhexyl) phthalate and mono(2-ethylhexyl) phthalate that can easily be implemented into existing multi-target methods used for sports drug testing. Quantification of the DEHP metabolites was accomplished after enzymatic hydrolysis of urinary glucuronide conjugates and direct injection using isotope-dilution liquid chromatography/tandem mass spectrometry. The method was fully validated for quantitative purposes considering the parameters specificity, linearity (1-250 ng/mL), inter- (2.4%-4.3%) and intra-day precision (0.7%-6.1%), accuracy (85%-105%), limit of detection (0.2-0.3 ng/mL), limit of quantification (1 ng/mL), stability and ion suppression effects. Urinary DEHP metabolites were measured in a control group without special exposure to DEHP (n = 100), in hospitalized patients receiving blood transfusion (n = 10), and in athletes (n = 468) being subject of routine doping controls. The investigation demonstrates that significantly increased levels of secondary DEHP metabolites were found in urine samples of transfused patients, strongly indicating blood transfusion.


Assuntos
Transfusão de Sangue , Dietilexilftalato/metabolismo , Dietilexilftalato/urina , Dopagem Esportivo , Detecção do Abuso de Substâncias/métodos , Adulto , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Cromatografia Líquida , Dietilexilftalato/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem , Adulto Jovem
7.
Schweiz Arch Tierheilkd ; 164(11): 709-720, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-34758948

RESUMO

INTRODUCTION: The prevalence of osteochondral changes in the metatarsal growth plates of fattening bulls was investigated. Plantarodorsal radiographic views of the metatarsal region of 204 hind legs from 102 slaughtered fattening bulls were taken. Radiographic lesions in metatarsal growth plates were confirmed in selected cases using computed tomography (n=14) and histology (n=6). Radiographic criteria for growth plate lesions were axis deviations between the metatarsal bones and the digit, radiolucencies in the growth plate, increased bone density in the metaphysis, irregularities of the growth plate and marginal osteophytes («lipping¼). The individual lesions were categorised as present/absent or 1 = slight, 2 = distinct, and 3 = severe. A weighted sum of these radiographic changes was generated for each growth plate and for each animal, and used for statistical analysis of the associations between husbandry factors and the occurrence of lesions. Almost all of the metatarsal bones had signs of osteochondral changes on the radiographs of the growth plates. The most common lesions were lipping (99,5 %), increased bone density in the metaphysis (66,6 %) and radiolucencies in the growth plates (64,1 %). Computed tomography and histology revealed hyperplasia of the margins of the epiphysis and metaphysis, focal increase in bone deposits accompanied by incomplete ossification and irregular and widened cartilage columns of the growth plate. There were statistically significant associations between the weighted radiographic changes and slaughter weight, average daily weight gain, husbandry practices and production label. The prevalence of radiographic lesions indicative for osteochondrosis of the metatarsal growth plates of fattening bulls slaughtered at a local abattoir was high. The extent to which the distinct and severe lesions are associated with reduced production and obvious clinical lameness requires further study.


INTRODUCTION: La prévalence des modifications ostéochondrales des plaques de croissance métatarsiennes des taureaux à l'engraissement a été étudiée. Des radiographies planto-dorsales de la région métatarsienne de 204 membres postérieurs de 102 taureaux d'engraissement abattus ont été réalisées. Les lésions radiographiques des plaques de croissance métatarsiennes ont été confirmées dans des cas sélectionnés par tomodensitométrie (n=14) et histologie (n=6). Les critères radiographiques des lésions du cartilage de conjugaison étaient les déviations de l'axe entre les os métatarsiens et les phalanges, les radiotransparences du cartilage de conjugaison, l'augmentation de la densité osseuse de la métaphyse, les irrégularités du cartilage de conjugaison et les ostéophytes marginaux (« lipping ¼). Les lésions individuelles ont été classées comme présentes/absentes ou 1 = légères, 2 = distinctes et 3 = sévères. Une somme pondérée de ces modifications radiographiques a été générée pour chaque plaque de croissance et pour chaque animal et utilisée pour l'analyse statistique des associations entre les facteurs d'élevage et l'apparition de lésions. Presque tous les os métatarsiens présentaient des signes de modifications ostéochondrales sur les radiographies des plaques de croissance. Les lésions les plus fréquentes étaient le « lipping ¼ (99,5 %), l'augmentation de la densité osseuse au niveau de la métaphyse (66,6 %) et les radiotransparences des plaques de croissance (64,1 %). La tomodensitométrie et l'histologie ont révélé une hyperplasie des marges de l'épiphyse et de la métaphyse, une augmentation focale des dépôts osseux accompagnée d'une ossification incomplète et des colonnes cartilagineuses irrégulières et élargies sur le cartilage de conjugaison. Il y avait des associations statistiquement significatives entre les changements radiographiques pondérés et le poids d'abattage, le gain de poids quotidien moyen, les pratiques d'élevage et les labels de production. La prévalence des lésions radiographiques révélatrices d'une ostéochondrose des plaques de croissance métatarsiennes des taureaux d'engraissement abattus dans un abattoir local était élevée. La mesure dans laquelle ces lésions distinctes et sévères sont associées à une production réduite et à une boiterie clinique évidente nécessite une étude plus approfondie.


Assuntos
Lâmina de Crescimento , Ossos do Metatarso , Animais , Bovinos , Epífises , Lâmina de Crescimento/diagnóstico por imagem , Masculino , Ossos do Metatarso/diagnóstico por imagem , Prevalência , Suíça
8.
Schweiz Arch Tierheilkd ; 152(5): 245-52, 2010 May.
Artigo em Alemão | MEDLINE | ID: mdl-20464684

RESUMO

The following case report describes a selenium toxicosis in a pig-fattening farm of two finisher groups. The diseased animals partly showed ataxia and paresis or intense lameness in connection with band-like ablation of the epidermis at the coronary band. Some of them suffered from alopecia. Foot-and-mouth disease and swine vesicular disease were excluded by serological tests. Dissection revealed a multifocal bilateral symmetric poliomyelomalacia. Histological changes in the claws ranged from severe cell-decay in the germinative layer to distinctive decay of the stratum corneum. Due to damage of the claw epidermis the corium was partly exposed. Feed analysis revealed 100-fold increased selenium content in the finishing premix from the feed mill and as a result 20- to 60-fold increased selenium values in feed samples from the farm-made finisher mixture. Selenium concentration in the blood of diseased animals was 4- to 10-fold higher than normal values, which confirmed the tentative diagnosis of a selenium toxicosis.


Assuntos
Ração Animal/intoxicação , Selênio/intoxicação , Doenças dos Suínos/patologia , Animais , Ataxia/induzido quimicamente , Ataxia/veterinária , Casco e Garras/patologia , Paresia/induzido quimicamente , Paresia/veterinária , Selênio/sangue , Suínos , Doenças dos Suínos/sangue
9.
J Vet Dent ; 27(3): 160-2, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21038833

RESUMO

This clinical report describes two horses with bilateral maxillary fractures following dental treatment. The fractures occurred during dental treatment by a veterinarian, and both had rostral, transverse, and complete bilateral maxillary fractures with instability and minimal displacement. The fractures were repaired using bilateral intraoral wiring with the patients under general anesthesia. The postoperative period was without complications and the fractures healed as expected. Maxillary fractures during or after routine dental treatment are rare, but can occur, especially in older horses. Appropriate sedation and, if necessary, regional nerve blocks might reduce the risk of iatrogenic fractures of the maxilla. General anesthesia must be considered for tooth extraction in horses that are difficult to restrain.


Assuntos
Odontologia/veterinária , Cavalos/lesões , Doença Iatrogênica/veterinária , Fraturas Maxilares/veterinária , Medicina Veterinária/métodos , Animais , Odontologia/métodos , Masculino , Fraturas Maxilares/diagnóstico por imagem , Fraturas Maxilares/etiologia , Fraturas Maxilares/cirurgia , Radiografia , Resultado do Tratamento
10.
Schweiz Arch Tierheilkd ; 151(4): 171-6, 2009 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-19333903

RESUMO

The following case report describes the treatment of canker in a 14 years old warmblood gelding. The horse showed the typical appearance with caseous surface and early detachment of the superficial horn layers. The histological results show a severe degradation in the germinal layer of the epidermis of the frog. Surgical therapy under general anaesthesia was performed. On all limbs a tourniquet was applied and all abnormal tissue in the region of the frog and also the subdermal tissue underneath were removed. Postoperatively the horse was treated with hoof bandages for 2 weeks. Treatment plates were than applied on all hoofs. During the following weeks the wounds were topically treated with Giessner Mischung 2 an astringent, desinfectant powder. The powder contains jodophorm, zincoxyde, tanninic acid, metronidazole. After 5 months the frog showed a complete cover with strong horn material and without any signs of recrudescence.


Assuntos
Dermatoses do Pé/veterinária , Casco e Garras/patologia , Casco e Garras/cirurgia , Doenças dos Cavalos/cirurgia , Animais , Dermatoses do Pé/patologia , Dermatoses do Pé/cirurgia , Doenças dos Cavalos/patologia , Cavalos , Masculino , Resultado do Tratamento
11.
Artigo em Inglês | MEDLINE | ID: mdl-19010743

RESUMO

Endogenous steroids are amongst the most misused doping agents in sports. Their presence poses a major challenge for doping control laboratories. Current threshold levels do not allow for the detection of all endogenous steroid misuse due to great interindividual variations in urinary steroid concentrations. A method has been developed and validated to screen for traditionally monitored endogenous steroids in doping control as well as specific hydroxylated/oxygenated metabolites in order to enhance the detection capabilities for the misuse of endogenous steroids.


Assuntos
Esteroides/metabolismo , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Fracionamento Químico , Cromatografia Gasosa , Dopagem Esportivo , Humanos , Hidrólise , Reprodutibilidade dos Testes
12.
Toxicol Lett ; 177(3): 198-204, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18325697

RESUMO

One of the most frequently misused steroid precursors (prohormones) is 19-norandrostenedione (4-estrene-3,17-dione, NOR), which is, after oral administration, readily metabolised to nortestosterone, also known as nandrolone (durabolin). In this study we have characterised molecular mechanisms of its action determined its tissue specific androgenic and anabolic potency after subcutaneous (s.c.) administration and investigated potential adverse effects. Receptor binding tests demonstrate that NOR binds with high selectivity to the AR. The potency of NOR to transactivate androgen receptor (AR) dependent reporter gene expression was 10 times lower as compared to dihydrotestosterone (DHT). In vivo experiments in orchiectomised rats demonstrated that s.c. treatment with NOR resulted only in a stimulation of the weight of the levator ani muscle; the prostate and seminal vesicle weights remained completely unaffected. Like testosterone, administration of NOR resulted in a stimulation of AR and myostatin mRNA expression in the gastrocnemius muscle. NOR does not affect prostate proliferation, the liver weight and the expression of the tyrosine aminotransferase gene (TAT) in the liver. Summarizing these data it is obvious that NOR, if administrated s.c. and in contrast to its metabolite nandrolone, highly selectively stimulates the growth of the skeletal muscle but has only weak androgenic properties. This observation may have relevance with respect to therapeutic aspects but also doping prevention.


Assuntos
Anabolizantes/toxicidade , Androstenodiona/análogos & derivados , Receptores Androgênicos/efeitos dos fármacos , Androgênios , Androstenodiona/administração & dosagem , Androstenodiona/metabolismo , Androstenodiona/toxicidade , Animais , Injeções Subcutâneas , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Ratos , Ratos Wistar , Propionato de Testosterona/farmacologia
13.
Schweiz Arch Tierheilkd ; 150(2): 57-67, 2008 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-18369050

RESUMO

The effects of three dietary selenium (Se) levels (0.15, 0.35 and 0.5 mg/kg dry matter (dm) and of two Se-compounds (sodium selenite and Se-yeast) on the Se-status, liver function and claw health were studied using 36 fattening bulls in a two-factorial feeding trial that lasted 16 weeks. The claw health was assessed macroscopically and microscopically. Compared to the two control diets containing 0.15 mg Se/kg dm, the intake of the diets containing 0.35 and 0.50 mg Se/kg dm significantly (P < 0.05) increased the Se-concentration in serum, hair, liver and skeletal muscle. Compared to sodium selenite the intake of Se-yeast resulted in significantly (P < 0.05) higher Se-concentration in serum, liver and hair. Concerning the claw horn quality, there was no significant difference between the different groups; the animals receiving organic Se tended to have a better histological score (P = 0.06) at the coronary band than the groups fed with sodium selenite. The serum vitamin E level decreased significantly (P < 0.05) with increasing Se-intake, which had no influence (P > 0.1) on growth and liver function parameters. With the exception of the decrease of the serum vitamin E level indicating an oxidative stress caused by a high Se-intake, no negative effects of dietary selenium exceeding recommended levels for 4 months were observed.


Assuntos
Dieta/veterinária , Suplementos Nutricionais , Casco e Garras/efeitos dos fármacos , Fígado/efeitos dos fármacos , Selênio/farmacologia , Animais , Bovinos , Masculino , Selênio/sangue , Selênio/metabolismo , Vitamina E/sangue
14.
Toxicol Lett ; 169(1): 64-71, 2007 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-17254722

RESUMO

Desoxymethyltestosterone (DMT), also known as Madol, is a steroid recently identified to be misused as a doping agent. Since, the knowledge of functions of this substance is rather limited, it was our aim to characterise the pharmacological profile of DMT and to identify potential adverse side effects. DMT was synthesised, its purity was confirmed and its biological activity was tested. The potency of Madol (DMT) to transactivate androgen receptor (AR) dependent reporter gene expression was two times lower as compared to dihydrotestosterone (DHT). Receptor binding tests demonstrate that DMT binds with high selectivity to the AR, binding to the progesterone receptor (PR) was low. In vivo experiments in orchiectomised rats demonstrated that treatment with DMT resulted only in a stimulation of the weight of the levator ani muscle; the prostate and seminal vesicle weights remained unaffected. Like testosterone, administration of DMT resulted in a stimulation of IGF-1 and myostatin mRNA expression in the gastrocnemius muscle. In the prostate proliferation was stimulated by TP (testosteronepropionate), but remained unaffected by DMT. Remarkably, treatment with DMT, in contrast to TP, resulted in a significant increase of the heart weight. In the liver, DMT slightly stimulates the expression of the tyrosine aminotransferase gene (TAT). Our results demonstrate that DMT is a potent AR agonist with an anabolic activity. Besides the levator ani weight, DMT also modulates the gene expression in the musculus gastrocnemius. The observed stimulation of TAT expression in the liver and the significant increase of the heart weight after DMT treatment can be taken as an indication for side effects. Summarizing these data it is obvious that DMT is a powerful anabolic steroid with selective androgen receptor modulators (SARM) like properties and some indications for toxic side effects. Therefore, there is a need for a strict control of a possible misuse.


Assuntos
Anabolizantes/farmacologia , Androstenóis/farmacologia , Dopagem Esportivo , Anabolizantes/efeitos adversos , Androstenóis/efeitos adversos , Animais , Western Blotting , Genes Reporter/genética , Coração/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Orquiectomia , Próstata/efeitos dos fármacos , Próstata/metabolismo , RNA/biossíntese , RNA/isolamento & purificação , Ratos , Receptores Androgênicos/efeitos dos fármacos , Receptores de Progesterona/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/metabolismo , Tirosina Transaminase/metabolismo
15.
Toxicol Lett ; 165(2): 149-55, 2006 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-16621347

RESUMO

Since the begining of the year 2005, the use of steroid precursors (prohormones) is illegal in the United States; nevertheless, there is still an enormous abuse of such substances. One of the most frequently misused steroids, often declared to be a prohormone, is 1-testosterone (17beta-hydroxy-5alpha-androst-1-en-3-one, 1-Testo). In this study, we have characterised molecular mechanisms of its action, determined its tissue specific androgenic and anabolic potency and investigated potential adverse effects. 1-Testo binds highly selective to the androgen receptor (AR) and has a high potency to stimulate AR dependent transactivation. In vivo an equimolar dose of 1-Testo has the same potency to stimulate the growth of the prostate, the seminal vesicles and the androgen sensitive levator ani muscle as the reference compound testosterone propionate (TP). Administration of 1-Testo, in contrast to TP, results in a significant increase of liver weight. Our results demonstrate that 1-Testo, even without being metabolised, is a very potent androgen. It binds selectively to the AR and transactivates AR dependent reporter genes. In vivo it has a high androgenic and anabolic potency and increases liver weight. In summary 1-Testo can be characterised as a typical anabolic steroid. It has to be assumed that consumption of this substance is associated with adverse side effects typical for this class of compounds. Therefore, a strict control of its ban is essential.


Assuntos
Anabolizantes/toxicidade , Fígado/efeitos dos fármacos , Próstata/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Glândulas Seminais/efeitos dos fármacos , Testosterona/análogos & derivados , Animais , Bioensaio , Expressão Gênica , Genes Reporter , Fígado/patologia , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/crescimento & desenvolvimento , Orquiectomia , Tamanho do Órgão/efeitos dos fármacos , Próstata/crescimento & desenvolvimento , RNA Mensageiro/metabolismo , Ratos , Receptores Androgênicos/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Glândulas Seminais/crescimento & desenvolvimento , Detecção do Abuso de Substâncias/métodos , Testosterona/metabolismo , Testosterona/toxicidade
16.
Toxicol Lett ; 164(1): 16-23, 2006 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-16356667

RESUMO

Tetrahydrogestrinone (THG) is a steroid recently identified to be misused as doping agent. However, the knowledge on functions of this substance in humans or animal models is rather limited. Therefore, it was our aim to further characterize the pharmacological profile of THG and identify potential adverse side effects. THG was synthesized, the purity was confirmed and its biological activity was tested. The potency of THG to transactivate AR dependent reporter gene expression was two orders of magnitude lower compared to dihydrotestosterone. THG binds with high affinity but unselective to the androgen (AR), progesterone (PR), glucocorticoid (GR) and mineralocorticoid (MR) receptor. Treatment of orchiectomised rats with THG resulted in a stimulation of prostate, seminal vesicle and levator ani muscle, indicating androgenic and anabolic properties. In the liver THG, in contrast to testosteronepropionate (TP), down regulates the expression of the GR dependent tyrosine aminotransferase gene (TAT). In summary, our results demonstrate that THG is not a specific AR agonist. THG exhibits a high binding affinity to all tested steroid hormone receptors and binds with highest affinity to the GR. Our in vivo data are indicative of an anabolic and androgenic potency of THG, but the repression of TAT demonstrates that THG also interferes with the glucocorticoid hormone system. Therefore, it is conceivable that an intake will result in adverse side effects.


Assuntos
Anabolizantes/farmacologia , Gestrinone/análogos & derivados , Fígado/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais/efeitos dos fármacos , Anabolizantes/efeitos adversos , Anabolizantes/química , Animais , Ligação Competitiva , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Gestrinone/efeitos adversos , Gestrinone/química , Gestrinone/farmacologia , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Estrutura Molecular , Músculo Liso/efeitos dos fármacos , Músculo Liso/patologia , Orquiectomia , Tamanho do Órgão/efeitos dos fármacos , Próstata/efeitos dos fármacos , Próstata/patologia , Ensaio Radioligante , Ratos , Ratos Wistar , Receptores Androgênicos/genética , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/patologia , Leveduras/genética
18.
Vet J ; 172(1): 173-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16772143

RESUMO

The pads of the bovine digital cushion, which serves as a shock absorber, have specific anatomical structures to cope with the substantial forces acting within the claw. To gain more information on the lipid composition and content of the pads, horn shoes from 12 slaughtered heifers and cows were removed and different samples of the pads excised with a scalpel. Pad lipids were extracted and the fatty acid composition determined by gas chromatography. Fat from perirenal and subcutaneous adipose tissues served as a comparison. Overall, this fat contained a higher quantity of extracted lipids than that of the claw pads and did not differ between heifers and cows. In contrast, lipid content in the pads was significantly higher in the cows than in the heifers. In both groups, the lipid content of the middle and abaxial pads, which are situated directly under the distal phalanx, was lower than in the pads of the other locations. The lipids in all pads contained >77% monounsaturated fatty acids (MUFA), differing sharply from the adipose tissue with values <51%. Among the polyunsaturated fatty acids (PUFA) a significantly higher proportion of arachidonic acid (AA) was found in the heifer pads than in those of the cows, whereas the proportion of AA was similar in the adipose tissue of all animals. The proportion of AA in the pad lipids also varied between the defined locations with the highest proportion found in locations that showed the lowest lipid content and was related to the age of the animal.


Assuntos
Bovinos/fisiologia , Ácidos Graxos/análise , Casco e Garras , Fatores Etários , Envelhecimento/fisiologia , Animais , Cromatografia Gasosa/métodos , Cromatografia Gasosa/veterinária , Ácidos Graxos/metabolismo , Feminino , Casco e Garras/anatomia & histologia , Casco e Garras/química , Casco e Garras/fisiologia
19.
Equine Vet J ; 38(6): 508-16, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17124840

RESUMO

REASONS FOR PERFORMING STUDY: The diagnosis of lameness caused by proximal metacarpal and metatarsal pain can be challenging. Magnetic resonance imaging (MRI) offers the possibility for further diagnosis but there have been no studies on the normal MRI appearance of the origin of the suspensory ligament (OSL) in conjunction with ultrasonography and histology. OBJECTIVES: To describe the MRI appearance of the OSL in fore- and hindlimbs of sound horses and compare it to the ultrasonographic and histological appearance. The findings can be used as reference values to recognise pathology in the OSL. METHODS: The OSL in the fore- and hindlimbs of 6 sound horses was examined by ultrasonography prior to death, and MRI and histology post mortem. Qualitative evaluation and morphometry of the OSL were performed and results of all modalities compared. RESULTS: Muscular tissue, artefacts, variable SL size and shape complicated ultrasonographic interpretation. In MRI and histology the forelimb OSL consisted of 2 portions, the lateral being significantly thicker than medial. The hindlimb SL had a single large area of origin. In fore- and hindlimbs, the amount of muscular tissue was significantly larger laterally than medially. Overall SL measurements using MRI were significantly higher than using histology and ultrasonography and histological higher than ultrasonographic measurements. Morphologically, there was a good correlation between MRI and histology. CONCLUSIONS: MRI provides more detailed information than ultrasonography regarding muscle fibre detection and OSL dimension and correlates morphologically well with histology. Therefore, ultrasonographic results should be regarded with caution. POTENTIAL RELEVANCE: MRI may be a diagnostic aid when other modalities fail to identify clearly the cause of proximal metacarpal and metatarsal pain; and may improve selection of adequate therapy and prognosis for injuries in this region.


Assuntos
Doenças dos Cavalos/diagnóstico , Cavalos/anatomia & histologia , Ligamentos/anatomia & histologia , Imageamento por Ressonância Magnética/veterinária , Ultrassonografia/veterinária , Animais , Membro Anterior , Membro Posterior , Doenças dos Cavalos/diagnóstico por imagem , Doenças dos Cavalos/patologia , Coxeadura Animal/diagnóstico , Coxeadura Animal/diagnóstico por imagem , Coxeadura Animal/patologia , Ligamentos/diagnóstico por imagem , Ligamentos/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Metacarpo/anatomia & histologia , Metacarpo/diagnóstico por imagem , Metacarpo/patologia , Metatarso/anatomia & histologia , Metatarso/diagnóstico por imagem , Metatarso/patologia , Dor/diagnóstico , Dor/diagnóstico por imagem , Dor/patologia , Dor/veterinária , Valores de Referência , Ultrassonografia/métodos
20.
Schweiz Arch Tierheilkd ; 148(2): 55-63, 2006 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-16509166

RESUMO

Fifty-four horses with hoof cracks were referred to the Equine Hospital of the University of Zurich, for treatment. The horses were admitted because of lameness or other symptoms caused by the cracks. Deep or complicated quarter cracks were the most common type of cracks diagnosed. Poor conformation and abnormal hoof shape were the most important causes of hoof crack development, whereas injury to the coronary band was a less frequently encountered cause. Effective treatment of this problem includes corrective shoeing, removing horn from the weight-bearing surface as well as from the crack with a Dremel tool and immobilization of the borders of the crack. However, even with such a therapy, the recurrence rate of hoof cracks was with 20% very high.


Assuntos
Doenças do Pé/veterinária , Casco e Garras/lesões , Doenças dos Cavalos/etiologia , Doenças dos Cavalos/patologia , Animais , Feminino , Doenças do Pé/etiologia , Doenças do Pé/patologia , Doenças do Pé/terapia , Casco e Garras/patologia , Doenças dos Cavalos/terapia , Cavalos , Incidência , Coxeadura Animal/etiologia , Masculino , Recidiva , Índice de Gravidade de Doença , Sapatos , Resultado do Tratamento , Suporte de Carga/fisiologia
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