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2.
Int J Sports Med ; 37(2): 154-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26509371

RESUMO

A proposed benefit of minimalist shoe running is an increase in intrinsic foot muscle strength. This study examined change in intrinsic foot muscle size in runners transitioning to Vibram FiveFingers™ minimalist shoes compared to a control group running in traditional running shoes. We compare pre-transition size between runners who developed bone marrow edema to those who did not. 37 runners were randomly assigned to the Vibram FiveFingers™ group (n=18) or control group (n=19). Runners' bone marrow edema and intrinsic foot muscle size were measured at baseline and after 10 weeks. Total running volume was maintained by all runners. A significant increase in abductor hallucis cross-sectional area of 10.6% occurred in the Vibram FiveFingers™ group compared to the control group (p=0.01). There was no significant change in any of the other muscles examined (p>0.05). 8 of the Vibram FiveFingers™ runners, and 1 control runner developed bone marrow edema. Those who developed bone marrow edema, primarily women, had significantly smaller size in all assessed muscles (p≤0.05). Size of intrinsic foot muscles appears to be important in safely transitioning to minimalist shoe running. Perhaps intrinsic foot muscle strengthening may benefit runners wanting to transition to minimalist shoes.


Assuntos
Pé/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Corrida/fisiologia , Sapatos , Adulto , Estatura , Peso Corporal , Medula Óssea/patologia , Edema/diagnóstico , Edema/etiologia , Desenho de Equipamento , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Corrida/lesões , Fatores Sexuais , Ultrassonografia , Adulto Jovem
3.
Br J Pharmacol ; 165(8): 2584-97, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21649637

RESUMO

BACKGROUND AND PURPOSE: Both CB(1) and CB(2) cannabinoid receptors have been shown to play a role in bone metabolism. Crucially, previous studies have focussed on the effects of cannabinoid ligands in murine bone cells. This study aimed to investigate the effects of cannabinoids on human bone cells in vitro. EXPERIMENTAL APPROACH: Quantitative RT-PCR was used to determine expression of cannabinoid receptors and liquid chromatography-electrospray ionization tandem mass spectrometry was used to determine the presence of endocannabinoids in human bone cells. The effect of cannabinoids on human osteoclast formation, polarization and resorption was determined by assessing the number of cells expressing α(v) ß(3) or with F-actin rings, or measurement of resorption area. KEY RESULTS: Human osteoclasts express both CB(1) and CB(2) receptors. CB(2) expression was significantly higher in human monocytes compared to differentiated osteoclasts. Furthermore, the differentiation of human osteoclasts from monocytes was associated with a reduction in 2-AG levels and an increase in anandamide (AEA) levels. Treatment of osteoclasts with LPS significantly increased levels of AEA. Nanomolar concentrations of AEA and the synthetic agonists CP 55 940 and JWH015 stimulated human osteoclast polarization and resorption; these effects were attenuated in the presence of CB(1) and/or CB(2) antagonists. CONCLUSIONS: AND IMPLICATIONS Low concentrations of cannabinoids activate human osteoclasts in vitro. There is a dynamic regulation of the expression of the CB(2) receptor and the production of the endocannabinoids during the differentiation of human bone cells. These data suggest that small molecules modulating the endocannabinoid system could be important therapeutics in human bone disease. LINKED ARTICLES: This article is part of a themed section on Cannabinoids in Biology and Medicine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-8. To view Part I of Cannabinoids in Biology and Medicine visit http://dx.doi.org/10.1111/bph.2011.163.issue-7.


Assuntos
Ácidos Araquidônicos/metabolismo , Glicerídeos/metabolismo , Osteoclastos/metabolismo , Alcamidas Poli-Insaturadas/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Animais , Osso e Ossos/metabolismo , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Endocanabinoides , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Osteoblastos/metabolismo , Osteoclastos/citologia , RNA Mensageiro/metabolismo , Receptor CB1 de Canabinoide/genética , Receptor CB2 de Canabinoide/genética , Proteínas rho de Ligação ao GTP/metabolismo
4.
Prev Vet Med ; 95(3-4): 186-97, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20554069

RESUMO

A retrospective cohort study involving 137 dairy herds randomly selected from all 390 participating in the Victorian Test and Control Program for bovine Johne's disease was undertaken to gain insight into the relationships between calf rearing practices and the occurrence of bovine Johne's disease on infected dairy farms. Each study farm was visited between July 2005 and January 2006 and a structured survey examining herd management and calf rearing practices was completed. The resultant data, along with information from annual herd testing for Johne's disease and records of clinical Johne's disease diagnosed in the herd, from May 1990 to March 2008, were analysed. Factors associated with time to the birth of the animal that was the first home-bred clinical case of Johne's disease or ELISA positive animal born after the second annual whole herd test in the herd were investigated using survival analysis methods. The publicly-subsidised Test and Control Program commenced in 1996. On the 1st of July 2003 the program was modified with more rigorous and externally audited calf rearing requirements introduced for all participants. The more stringent calf rearing requirements introduced in July 2003 appear to have translated into significantly reduced disease transmission within the infected study herds.


Assuntos
Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/normas , Doenças dos Bovinos/transmissão , Indústria de Laticínios , Paratuberculose/transmissão , Animais , Animais Recém-Nascidos , Anticorpos Antibacterianos/sangue , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Estimativa de Kaplan-Meier , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/epidemiologia , Paratuberculose/prevenção & controle , Estudos Retrospectivos , Medição de Risco , Inquéritos e Questionários , Vitória/epidemiologia
5.
Aust Vet J ; 88(7): 249-54, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20579029

RESUMO

OBJECTIVE: To compare the results of radiometric culture conducted in three Australian laboratories for Mycobacterium avium subsp. paratuberculosis (Mptb) using bulk vat and individual animal milk samples. PROCEDURE: Milk samples were collected from 15 cows exhibiting clinical signs of Johne's disease, and subsequently confirmed as infected with Mptb, and from the bulk milk vats on 91 farms running herds known to be infected with Mptb. Each milk sample was divided into three equivalent samples and one of each of the replicates was forwarded to the three participating laboratories. The identity and nature of the samples was protected from the study collaborators. The laboratories processed the samples and undertook radiometric culture for Mptb using their standard method. Results of testing were provided to the principal investigator for collation and analysis. RESULTS: In total, 2 (2.2%) of 91 vat-milk samples and 8 (53.3%) of 15 individual cows' milk samples returned positive radiometric milk culture results. Only one sample, from a clinical case of Johne's disease, was identified as positive by more than one laboratory. There were differences in the absolute frequency with which Mptb was identified in the milk samples by the collaborating laboratories. CONCLUSIONS: Mptb was cultured from a very small percentage of Australian raw bulk milk samples sourced from known infected herds. By contrast, Mptb was successfully cultured from half of the milk samples collected from clinically affected cows. There was no statistical difference between laboratories in the proportion of vat samples or individual animal milk samples in which Mptb was detected.


Assuntos
Laboratórios/normas , Leite/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/diagnóstico , Radiometria/veterinária , Animais , Bovinos , Feminino , Humanos , Paratuberculose/transmissão , Radiometria/normas , Sensibilidade e Especificidade , Vitória , Zoonoses
6.
Aust Vet J ; 83(7): 431-4, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16035185

RESUMO

OBJECTIVE: To estimate the sensitivity, specificity and detection limits for two bulk-milk enzyme-linked immunosorbent assays, the Svanovir BLV-gp51-Ab and the Lactelisa BLV Ab Bi indirect tank 250, for the detection of antibody to bovine leucosis virus in milk. PROCEDURE: Milk samples from 27 cows known to have enzootic bovine leucosis (EBL) were serially diluted with milk from a herd known to be free from the disease. The dilution at which antibodies could no longer be detected by each test was determined. A total of 1959 bulk-milk samples submitted to a laboratory for the Victorian (EBL) eradication program were tested with both the Svanovir and the Lactelisa assays. A Bayesian approach was used to calculate maximum-likelihood estimates of test sensitivity and specificity. An additional 660 bulk-milk samples were tested with both the Svanovir and the Lactelisa assays. Herds that had positive results on either or both of the assays were subjected to blood or milk testing of individual cattle. RESULTS: The dilution of milk at which the Svanovir assay failed to detect enzootic bovine leucosis antibody in half of the samples was 1 in 40, whereas the comparable value for the Lactelisa was 1 in 200. Computer modeling of the operating characteristics of the Svanovir assay indicated that the sensitivity of that assay would be considerably lower than that for the Lactelisa, and the specificity was estimated to be higher. Evaluation of the assays using 660 bulk-milk samples showed that the Lactelisa assay detected four infected herds that were not detected by the Svanovir test. No false positive results were recorded for either assay. CONCLUSION: Use of the Lactelisa assay in the Victorian EBL eradication program will enhance disease detection and eradication, but may also result in an increased frequency of false positive bulk-milk test results.


Assuntos
Anticorpos Antivirais/análise , Leucose Enzoótica Bovina/diagnóstico , Leucose Enzoótica Bovina/virologia , Vírus da Leucemia Bovina/imunologia , Leite/química , Animais , Bovinos , Indústria de Laticínios , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Vírus da Leucemia Bovina/isolamento & purificação , Valor Preditivo dos Testes , Sensibilidade e Especificidade
7.
Aust Vet J ; 83(1-2): 85-90, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15971827

RESUMO

OBJECTIVE: To assess the degree of compliance with recommended management procedures for the control of bovine Johne's disease and study the relationship between aspects of calf management and testing/disease outcomes in the herds. PROCEDURE: Fifty-four south Gippsland dairy herds participating in the Victorian bovine Johne's disease test and control program were visited between July and November 2002 and an audit of calf rearing practices was conducted. The results of testing completed under the program were analysed for each of the herds. Twenty seven management factors were examined for a relationship with the presence of clinical cases of Johne's disease or cattle with positive ELISA test results that were born after the completion of the second whole herd test. Logistic regression was used to examine the strength of relationships between the management practices and the frequency with which new cases of Johne's disease arose. RESULTS AND CONCULSIONS: Calves were removed from their dams within 12 hours of birth in only 17 (31.5%) of the herds. However, in all but one herd the calves were removed within 24 hours of birth. In 42 herds (77.8%) calf rearing facilities were adequately separated from adult cattle and the faeces from adult cattle. In 41 herds (75.9%) calves up to the age of 12 months were grazed on paddocks that were free of manure or effluent from adult cattle. However, in only 10 (18.5%) of the herds were all three of these calf management practices applied. Feeding whole milk containing antibiotic residues, or providing water for calves from birth, were found to have statistically significant associations with an increased occurrence of cases of bovine Johne's disease in the study herds. The practice of allowing cows to calve in a paddock was found to be associated with reduced occurrence of bovine Johne's disease. These associations were still found after analysis that included herd size, the number of clinical cases that had occurred in the herds before the start of testing, the number of animals with positive ELISA tests that were detected at the first test and the number of years of participation in the test and cull program. Early separation of newborn calves from cows and grazing calves under 12 months of age in areas free of adult cattle were not found to be protective against Johne's disease.


Assuntos
Criação de Animais Domésticos/normas , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Paratuberculose/epidemiologia , Paratuberculose/prevenção & controle , Animais , Animais Recém-Nascidos , Bovinos , Doenças dos Bovinos/etiologia , Indústria de Laticínios/normas , Feminino , Fidelidade a Diretrizes , Paratuberculose/etiologia , Inquéritos e Questionários , Vitória/epidemiologia
8.
J Chromatogr A ; 924(1-2): 471-81, 2001 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-11521899

RESUMO

This paper describes a pharmacokinetic study performed in Sprague-Dawley rats after i.v. administration of a single 6-mg/kg dose of 2beta-carbomethoxy-3beta-(4-fluorophenyl)-N-(3-iodo-E-allyl)nortropane (Altropane). Plasma samples were collected from the retro-orbital sinus at times up to 3 h after drug administration, extracted by solid-phase extraction, and the drug levels determined by capillary electrophoresis (CE). Pharmacokinetic parameters were determined by a standard noncompartmental model using WinNonlin version 1.5. The maximum plasma concentrations, clearances of the drug, and areas under the curve for male and female rats were 5.74 and 7.26 microg/ml, 135.7 and 98.5 ml/kg x min, and 44.23 and 60.92 microg x min/ml, respectively. The drug was cleared very rapidly from the systemic circulation, with a terminal t(1/2) of 7 to 10 min and a mean residence time of about 11 min for both sexes. The volume of distribution was approximately 1 l/kg. No metabolites were detected when the samples were analyzed individually. However, after samples were pooled and concentrated, traces of two unknown peaks that may represent metabolites were detected in concentrates from the last two timepoints. Part I of this work [J. Chromatogr. A, 895 (2000) 87] describes validation of CE methods for the analysis of aqueous and plasma samples of Altropane, including its solid-phase extraction from rat plasma.


Assuntos
Cocaína/sangue , Eletroforese Capilar/métodos , Animais , Área Sob a Curva , Cocaína/análogos & derivados , Cocaína/farmacocinética , Feminino , Masculino , Ratos , Ratos Sprague-Dawley
9.
Cancer Genet Cytogenet ; 126(1): 8-12, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11343772

RESUMO

We describe very uncommon phenotypic and cytogenetic findings in a 40-year-old female with blast phase of Philadelphia chromosome (Ph)-positive CML. In addition to the t(9;22)(q34;q11) that was detected in all metaphases, a t(11;17)(q23;q21) was identified in 15 of 20 metaphases. Reverse transcription-polymerase chain reaction showed the major and minor bcr/abl fusion transcripts in the cells from a bone marrow (BM) sample. Fluorescence in situ hybridization (FISH) analysis also showed that fusion signals of the bcr and abl probes were found in 95% of blastic cells and in 64% of neutrophils. MLL gene rearrangement was also detected in some blastic cells but not in neutrophils by FISH analysis. Phenotypically, blastic cells expressed mixed lineage antigens such as CD34, CD33, CD13, CD19, CD7, and CD41. Immunogenotypically, some population of BM cells showed monoclonal rearrangements of immunoglobulin heavy chain and T-cell receptor gamma chain genes by Southern blot analysis. Clinical course was aggressive, and therapy was poorly tolerated. Such findings seem to support an association between Ph and an abnormality of 11q23 with poor prognosis, and suggest that the expression of both abnormal genes may be related to this mixed lineage antigen-expressing leukemia.


Assuntos
Antígenos/imunologia , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 17 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proto-Oncogenes , Fatores de Transcrição , Translocação Genética , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Southern Blotting , Transplante de Medula Óssea , Terapia Combinada , Proteínas de Ligação a DNA/genética , Feminino , Proteínas de Fusão bcr-abl/genética , Genótipo , Histona-Lisina N-Metiltransferase , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Proteína de Leucina Linfoide-Mieloide , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
J Pept Res ; 57(2): 151-61, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11168898

RESUMO

Among the many opioid peptides developed to date as nonaddictive analgesics, biphalin has exhibited extraordinary high potency and many other desirable characteristics. Biphalin is an octapeptide consisting of two monomers of a modified enkephalin, attached via a hydrazine bridge, and with the amino acids assembled in a palindromic sequence. Its structure is (Tyr-D-Ala-Gly-Phe-NH-)-2. However, this unique peptide, like any other synthetic peptide, needs strict quality control because of certain drawbacks associated with peptide synthesis. This paper discusses our approaches to characterizing and analyzing biphalin. Many techniques were used, including elemental analysis, amino acid analysis, amino acid sequence analysis (AASA), mass spectrometry (MS), 1H-NMR, 1H-correlated spectroscopy (COSY)-NMR, high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE). Electrospray ionization (ESI) mass spectrometry, which included both ESI-MS and ESI-MS/MS, was performed to confirm the full sequence because AASA results alone verified only the monomer sequence, and not the full sequence. Although the 1H-NMR results led to a preliminary assignment of many protons, the 1H COSY-NMR results allowed for unequivocal assignment of almost all protons. Peptide purity was determined using two techniques, reversed-phase HPLC and CE. The counter-ion of the peptide, trifluoroacetic acid, was determined by CE, using an indirect detection method developed previously in our laboratory. This paper illustrates successful application of nonconventional techniques to characterize and analyze a structurally modified peptide, biphalin, when standard techniques for peptide analysis are inadequate.


Assuntos
Encefalinas/química , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Encefalinas/isolamento & purificação , Ressonância Magnética Nuclear Biomolecular , Espectrometria de Massas por Ionização por Electrospray
11.
J Chromatogr A ; 895(1-2): 87-100, 2000 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-11105851

RESUMO

Altropane, 2beta-carbomethoxy-3beta-(4-fluorophenyl)-N-(3-iodo-E-allyl)nor tropane, is an imaging agent that was developed recently for early detection of Parkinson's disease. Its promise as a useful radiopharmaceutical for single-photon emission computed tomography or positron emission tomography imaging of the brain has been well demonstrated, and it is currently undergoing clinical trials. This paper presents methods development and validation of capillary electrophoresis (CE) techniques to analyze Altropane in aqueous environments as well as in rat plasma, using an internal standard, nicotinamide. N-Allylaltropane, 2beta-carbomethoxy-3beta-(4-fluorophenyl)-N-allylnortropane, which is a known degradation product of the Altropane precursor (tributyltinaltropane), was used to verify the method's specificity. A solid-phase extraction method for extraction of Altropane from rat plasma is also described. The results presented in this paper demonstrate the applicability of CE methods to study the pharmacokinetic properties of Altropane in animal models. The results of the pharmacokinetic study will be published later, as Part II.


Assuntos
Cocaína/análogos & derivados , Cocaína/sangue , Eletroforese Capilar/métodos , Compostos Radiofarmacêuticos/sangue , Animais , Ratos , Padrões de Referência , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
12.
J Am Geriatr Soc ; 48(11): 1483-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11083328

RESUMO

Four families highly clustered for extreme longevity are described here, representing the first report of clustering for this phenotype. Families such as these may prove to be helpful in the further understanding of the genetic contribution to achieving exceptional longevity.


Assuntos
Envelhecimento/genética , Família , Longevidade/genética , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Feminino , Humanos , Masculino , Fenótipo
14.
Clin Cancer Res ; 5(9): 2566-70, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10499634

RESUMO

Dihydropyrimidine dehydrogenase (DPD) is responsible for degradation of the pyrimidines uracil and thymine and the inactivation of the chemotherapeutic agent 5-fluorouracil. DPD activity is highly variable in cancer populations, and this variation may influence the antitumor efficacy of 5-fluorouracil. However, little is known about the regulation of DPD mRNA expression in any tissues. Using a reverse transcription competitive PCR assay, we quantified DPD mRNA levels in 10 matched colorectal tumors and adjacent normal mucosae and 7 colorectal liver metastases and adjacent normal livers. Lower levels of DPD mRNA expression were observed in colorectal tumor compared with adjacent normal colon mucosa (median, 0.01 versus 0.37 amole/microg total RNA, P = 0.02). DPD mRNA expression was also lower in metastases than adjacent normal liver tissue (median, 0.11 versus 1.17 amole/microg total RNA, P = 0.001). DPD mRNA expression was higher in normal liver than normal colonic mucosa (median, 1.17 versus 0.37 amole/microg total RNA, P = 0.02). A significant relationship was observed between DPD mRNA and catalytic activity (r(s) = 0.66, P<0.001). The tumor:normal ratio for DPD mRNA, protein, and activity was relatively stable in liver (0.25, 0.55, and 0.51, respectively) but varied considerably in colon (0.085, 0.9, and 1.25, respectively), consistent with enhanced translation of DPD transcript in primary colorectal tumor. This suggests that DPD can be regulated at the levels of both transcription and translation.


Assuntos
Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Oxirredutases/genética , Colo/enzimologia , Neoplasias Colorretais/patologia , Di-Hidrouracila Desidrogenase (NADP) , Humanos , Mucosa Intestinal/enzimologia , Fígado/enzimologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/secundário , Oxirredutases/biossíntese , Oxirredutases/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
15.
Aust Vet J ; 77(2): 113-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10078359

RESUMO

OBJECTIVE: To investigate the development of immune responses in calves experimentally and naturally infected with Mycobacterium paratuberculosis and to evaluate the potential for diagnostic tests to detect infected calves. DESIGN: Sequential testing of four treatment groups of calves over a 2 year period. PROCEDURE: Twenty-nine calves were allocated to four groups. Group D calves were orally dosed with M paratuberculosis, group N calves naturally exposed to M paratuberculosis, group V calves vaccinated for M paratuberculosis, and group C were control calves (not infected or vaccinated). Blood and faecal specimens were collected from each calf at monthly intervals to 18 months of age and then every 2 months until they were slaughtered between the ages of 21 and 29 months. Specimens were tested using absorbed EIA, IFN-gamma EIA and faecal culture. The infection status of the calves was confirmed by extensive histopathological examination and tissue culture. RESULTS: M paratuberculosis infection was confirmed in 10 calves, comprising six of eight orally dosed calves, three of five naturally exposed calves and one of nine vaccinated calves. The six artificially infected calves and one naturally infected calf were detected shedding M paratuberculosis in their faeces. Results with positive absorbed EIA were obtained from one artificially infected calf, one naturally infected calf and three vaccinated calves. All calves including controls had positive results on at least one occasion using the IFN-gamma EIA. In addition, seven calves had positive bovine tuberculosis results using the IFN-gamma EIA, even though bovine tuberculosis has been eradicated from Australia. CONCLUSION: Detection of M paratuberculosis infection in young cattle continues to be difficult using current tests.


Assuntos
Doenças dos Bovinos/diagnóstico , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/diagnóstico , Animais , Vacinas Bacterianas/imunologia , Bovinos , Doenças dos Bovinos/prevenção & controle , Fezes/microbiologia , Feminino , Histocitoquímica , Técnicas Imunoenzimáticas/veterinária , Interferon gama/sangue , Paratuberculose/prevenção & controle , Reação em Cadeia da Polimerase/veterinária , Vacinação/veterinária
16.
J Chromatogr A ; 817(1-2): 153-61, 1998 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-9764489

RESUMO

Synthetic peptide samples may contain counter-ions such as acetate or trifluoroacetate as a result of their method of preparation. Furthermore, because acetic acid (HOAc) and trifluoroacetic acid (TFA) are frequently used reagents in peptide synthesis, these acids may be found in synthetic peptide samples as impurities. This paper describes a method validation to determine HOAc and TFA in synthetic peptide samples by capillary electrophoresis (CE) using an internal standard (I.S.) with indirect UV detection. Typical analytical parameters such as precision, linearity, accuracy, specificity, limit of detection and ruggedness were evaluated during the validation. In addition, the contents of HOAc and TFA in two synthetic opioid peptide samples, TIPP[psi] and Orphanin FQ, were determined using the validated method. A unique feature of the method is that it offers determination of both acids in a single assay using a common I.S. The method is very efficient because of relatively short electrophoretic migration times (typically 2 to 8 min) for the acids investigated. This paper also discusses the factors that affect precision in a CE assay.


Assuntos
Ácido Acético/análise , Eletroforese Capilar/métodos , Oligopeptídeos/química , Peptídeos Opioides/química , Ácido Trifluoracético/análise , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Nociceptina
17.
Br J Clin Pharmacol ; 46(2): 151-6, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9723824

RESUMO

AIMS: Dihydropyrimidine dehydrogenase (DPD) catalyses the reduction of pyrimidines, including the anticancer agent 5-fluorouracil (5FU). Impaired 5FU degradation, through low DPD activity, has led to severe, life-threatening or fatal toxicity after administration of 5FU. Complete DPD deficiency is associated with the inherited metabolic disease thymine uraciluria. Several mutations in the gene encoding DPD have recently been identified, but the phenotype-genotype concordance of these alterations in the general population has not been reported. METHODS: Mononuclear cells were isolated from whole blood and DPD activity was determined after ex vivo incubation with 14C-5FU followed by h.p.1.c. analysis of 5FU metabolites. Analysis of mutations in the DPD gene at an exon splice site, codons 534, 543, and 732, and a deletion at base 1897 (deltaC1897) were performed in 30 subjects with the lowest and 30 subjects with the highest enzyme activity using PCR-RFLP. RESULTS: DPD activity was measured in 226 Caucasian subjects and was highly variable (range 19.1-401.4 pmol min(-1)mg(-1) protein). Mutations were frequently observed at codons 543 (allele frequency 28%), 732 (allele frequency 5.8%), and 534 (allele frequency 0.8%), but were not associated with low DPD activity. There were no splice site or deltaC1897 mutations found in this population. CONCLUSIONS: The five mutations analysed in this study are insufficient for identification of patients at risk for 5FU toxicity or thymine uraciluria. Both the splice site mutation and deltaC1897 are relatively rare in the general Caucasian population. Therefore, identification of further molecular alterations is required to facilitate the use of DPD analysis in genetic diagnosis and cancer therapeutics.


Assuntos
Leucócitos Mononucleares/enzimologia , Oxirredutases/genética , População Branca/genética , Alelos , Di-Hidrouracila Desidrogenase (NADP) , Feminino , Humanos , Masculino , Oxirredutases/metabolismo , Mutação Puntual , Escócia , Fumar
18.
Leukemia ; 12(6): 887-92, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9639416

RESUMO

The molecular mechanisms underlying the development and evolution of myelodysplastic syndrome (MDS) are largely unknown. The increasing number of blast cells in the bone marrow correlate with poor prognosis and risk of developing acute leukemia. Such progression is frequently associated with increasing chromosomal abnormalities and genetic mutations. A cohort of 75 MDS patients were investigated for RAS, FMS and p53 mutations, and these molecular findings were related to cytogenetics, clinical status, transformation to acute leukemia, prognostic scores and survival. A mutation incidence of 57% (43/75) was found, with 48% (36/75) RAS mutations, 12% (9/75) FMS mutations and 8% (4/50) p53 mutations. The mutation status for RAS and FMS was related to MDS subgroup, increasing with poor-risk disease. The highest incidence was in the chronic myelomonocytic leukemia (CMML) subgroup. The most frequent RAS mutations were of codon 12 and a predominance of FMS codon 969 mutations was observed. A statistically significant increased frequency of transformation to AML was observed in MDS patients harboring RAS or FMS mutations (P < 0.02). Patients with oncogene mutations had a significantly poorer survival compared with those without mutations at 2 years and at the end of the period of follow-up (P < 0.02). Multivariate analysis including mutation, age, gender, diagnosis (FAB), cytogenetics and International score shows that the International score and mutation and age is the best predictive model of a poor outcome, (P < 0.0001). When the analysis was undertaken without the International score, mutation and gender was the best predictor of poor survival (P = 0.005). This study shows that oncogene mutation, indicative of genetic instability, is associated with disease progression and poor survival in MDS.


Assuntos
Genes fms , Genes p53 , Genes ras , Mutação , Síndromes Mielodisplásicas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Leucemia Mieloide Aguda/etiologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Taxa de Sobrevida
19.
Genes Chromosomes Cancer ; 21(3): 256-9, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9523202

RESUMO

The ETV6 (TEL) locus at chromosome band 12p 13 is a major site of translocations in acute leukemia, particularly in childhood acute lymphoblastic leukemia (ALL). In cases with translocations involving ETV6, the normal ETV6 allele is often deleted. In addition, loss of heterozygosity of ETV6 is frequently observed in childhood'ALL. Thus, it has been suggested that ETV6 may have an anti-oncogenic role to play, in addition to its oncogenic role. We have described an unusual case of ALL in which ETV6 is found fused to the ABL gene; ABL is normally activated by fusion to the BCR gene in the 9:22 translocation. We expanded the primary cells from this ETV6/ABL rearranged case of ALL in SCID animals and analyzed them for expression of both ETV6/ABL and the normal ETV6 mRNA. We found that both the rearranged and normal ETV6 mRNAs are expressed in the expanded cell population. Furthermore, sequence analysis of the ETV6 PCR product revealed no point mutations which would influence the amino acid sequence. Thus, deletion of the second ETV6 allele is not necessary for the transformation to leukemia by ETV6/ABL.


Assuntos
Alelos , Proteínas de Ligação a DNA/genética , Genes abl/genética , Leucemia/genética , Proteínas Repressoras , Proteínas Oncogênicas de Retroviridae/genética , Deleção de Sequência/genética , Fatores de Transcrição/genética , Translocação Genética , Doença Aguda , Humanos , Proteínas Proto-Oncogênicas c-ets , Variante 6 da Proteína do Fator de Translocação ETS
20.
Br J Cancer ; 77(3): 497-500, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9472650

RESUMO

Individuals with a deficiency in the enzyme dihydropyrimidine dehydrogenase (DPD) may experience severe life-threatening toxicity when treated with 5-fluorouracil (5-FU). As routine measurement of enzyme activity is not practical in many clinical centres, we have investigated the use of DNA mutation analysis to identify cancer patients with low enzyme levels. We have identified two new mutations at codons 534 and 543 in the DPD cDNA of a patient with low enzyme activity and screened the DNA from 75 colorectal cancer patients for these mutations and the previously reported splice site mutation (Vreken et al, 1996; Wei et al, 1996). In all cases, DPD enzyme activity was also measured. The splice site mutation was detected in a patient (1 out of 72) with low enzyme activity whereas mutations at codons 534 (2 out of 75) and 543 (11 out of 23) were not associated with low enzyme activity. These studies highlight the need to combine DPD genotype and phenotype analysis to identify mutations that result in reduced enzyme activity.


Assuntos
Neoplasias Colorretais/enzimologia , Oxirredutases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Códon , Neoplasias Colorretais/genética , Di-Hidrouracila Desidrogenase (NADP) , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Oxirredutases/metabolismo , Polimorfismo Genético
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