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1.
Drug Discov Today ; 24(1): 37-41, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30196006

RESUMO

Thiopurine drugs continue to be a cornerstone of inflammatory bowel disease (IBD) treatment. Thiopurines are economical compared with many newer medical treatments for IBD, other chronic inflammatory diseases and leukaemia, although they are not without their shortcomings. These include a slow-onset therapeutic action and many adverse drug reactions. This feature article surveys published data, unpublished in vitro and in vivo experiments, as well as clinical experience, underpinning a rationale for bringing a novel thiopurine drug formulation to market. This formulation has a rapid action making it suitable for the induction and maintenance treatment of IBD and avoids most thiopurine-associated adverse reactions.


Assuntos
Imunossupressores/administração & dosagem , Doenças Inflamatórias Intestinais/tratamento farmacológico , Tioguanina/administração & dosagem , Administração Retal , Animais , Doença Hepática Induzida por Substâncias e Drogas , Humanos , Imunossupressores/efeitos adversos , Mucosa Intestinal/metabolismo , Tioguanina/efeitos adversos
2.
Mol Genet Metab ; 119(1-2): 83-90, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27370710

RESUMO

BACKGROUND: Miller syndrome (post-axial acrofacial dysostosis) arises from gene mutations for the mitochondrial enzyme dihydroorotate dehydrogenase (DHODH). Nonetheless, despite demonstrated loss of enzyme activity dihydroorotate (DHO) has not been shown to accumulate, but paradoxically urine orotate has been reported to be raised, confusing the metabolic diagnosis. METHODS: We analysed plasma and urine from a 4-year-old male Miller syndrome patient. DHODH mutations were determined by PCR and Sanger sequencing. Analysis of DHO and orotic acid (OA) in urine, plasma and blood-spot cards was performed using liquid chromatography-tandem mass spectrometry. In vitro stability of DHO in distilled water and control urine was assessed for up to 60h. The patient received a 3-month trial of oral uridine for behavioural problems. RESULTS: The patient had early liver complications that are atypical of Miller syndrome. DHODH genotyping demonstrated compound-heterozygosity for frameshift and missense mutations. DHO was grossly raised in urine and plasma, and was detectable in dried spots of blood and plasma. OA was raised in urine but undetectable in plasma. DHO did not spontaneously degrade to OA. Uridine therapy did not appear to resolve behavioural problems during treatment, but it lowered plasma DHO. CONCLUSION: This case with grossly raised plasma DHO represents the first biochemical confirmation of functional DHODH deficiency. DHO was also easily detectable in dried plasma and blood spots. We concluded that DHO oxidation to OA must occur enzymatically during renal secretion. This case resolved the biochemical conundrum in previous reports of Miller syndrome patients, and opened the possibility of rapid biochemical screening.


Assuntos
Anormalidades Múltiplas/genética , Deformidades Congênitas dos Membros/genética , Disostose Mandibulofacial/genética , Micrognatismo/genética , Ácido Orótico/análogos & derivados , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Anormalidades Múltiplas/sangue , Anormalidades Múltiplas/fisiopatologia , Anormalidades Múltiplas/urina , Pré-Escolar , Di-Hidro-Orotato Desidrogenase , Genótipo , Humanos , Deformidades Congênitas dos Membros/sangue , Deformidades Congênitas dos Membros/fisiopatologia , Deformidades Congênitas dos Membros/urina , Masculino , Disostose Mandibulofacial/sangue , Disostose Mandibulofacial/fisiopatologia , Disostose Mandibulofacial/urina , Micrognatismo/sangue , Micrognatismo/fisiopatologia , Micrognatismo/urina , Mutação , Ácido Orótico/sangue , Ácido Orótico/urina , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/sangue , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/urina , Uridina/sangue , Uridina/urina
3.
PLoS One ; 10(9): e0135047, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26325665

RESUMO

INTRODUCTION: Xanthine oxidase (XO) is distributed in mammals largely in the liver and small intestine, but also is highly active in milk where it generates hydrogen peroxide (H2O2). Adult human saliva is low in hypoxanthine and xanthine, the substrates of XO, and high in the lactoperoxidase substrate thiocyanate, but saliva of neonates has not been examined. RESULTS: Median concentrations of hypoxanthine and xanthine in neonatal saliva (27 and 19 µM respectively) were ten-fold higher than in adult saliva (2.1 and 1.7 µM). Fresh breastmilk contained 27.3 ± 12.2 µM H2O2 but mixing baby saliva with breastmilk additionally generated >40 µM H2O2, sufficient to inhibit growth of the opportunistic pathogens Staphylococcus aureus and Salmonella spp. Oral peroxidase activity in neonatal saliva was variable but low (median 7 U/L, range 2-449) compared to adults (620 U/L, 48-1348), while peroxidase substrate thiocyanate in neonatal saliva was surprisingly high. Baby but not adult saliva also contained nucleosides and nucleobases that encouraged growth of the commensal bacteria Lactobacillus, but inhibited opportunistic pathogens; these nucleosides/bases may also promote growth of immature gut cells. Transition from neonatal to adult saliva pattern occurred during the weaning period. A survey of saliva from domesticated mammals revealed wide variation in nucleoside/base patterns. DISCUSSION AND CONCLUSION: During breast-feeding, baby saliva reacts with breastmilk to produce reactive oxygen species, while simultaneously providing growth-promoting nucleotide precursors. Milk thus plays more than a simply nutritional role in mammals, interacting with infant saliva to produce a potent combination of stimulatory and inhibitory metabolites that regulate early oral-and hence gut-microbiota. Consequently, milk-saliva mixing appears to represent unique biochemical synergism which boosts early innate immunity.


Assuntos
Imunidade Inata , Microbiota , Leite Humano , Boca , Saliva , Adulto , Feminino , Recém-Nascido , Masculino , Peróxido de Hidrogênio/análise , Hipoxantina/análise , Imunidade Inata/imunologia , Imunidade Inata/fisiologia , Microbiota/imunologia , Leite Humano/química , Leite Humano/imunologia , Leite Humano/fisiologia , Boca/imunologia , Boca/microbiologia , Nucleotídeos/análise , Nucleotídeos/metabolismo , Saliva/química , Saliva/imunologia , Tiocianatos/análise , Xantina/análise , Xantina Oxidase/análise , Humanos
4.
J Anal Toxicol ; 39(2): 140-3, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25342718

RESUMO

In Australia, it is a requirement of workplace oral fluid (OF) drugs of abuse testing that drug recovery from collection devices be verified by an accredited laboratory. Recovery data are used in conjunction with collection volume imprecision data and uncertainty of measurement to provide an estimation of drug concentration in neat OF. The manufacturer's product information for the DCD5000 collection device indicates that the collection volume of the swab is 380 µL. Recovery data for the swab when used with the isopropanol provided by the manufacturer are not available. A series of experiments using fortified drug-free OF were performed to assess the collection volume imprecision of the Dräger DCD5000 swab and the recovery of drugs from the swab using isopropanol. The fortified OF was collected with the swabs (n = 16), and swabs were discharged into vials of isopropanol as per the manufacturer's instructions. The mean collection volume of the DCD5000 swab was 487 µL with an imprecision of 1.3%. Recovery of drug from the device ranged from 86 to 98% for drugs listed in the Australian OF workplace testing standard. Recovery of methadone, buprenorphine and norbuprenorphine ranged from 93 to 102%. Recovery of 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidene was 45%, suggesting that urine is more suitable sample if methadone therapy is being monitored. Overall, drug recovery from the device using isopropanol was acceptable when the increased collection volume of the swab was taken into account.


Assuntos
Detecção do Abuso de Substâncias/instrumentação , 2-Propanol/análise , Austrália , Humanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-22521213

RESUMO

An LC-MS/MS method for the quantitation of urinary metabolites of eight JWH-type synthetic cannabinoids (SCs) has been developed and validated. Urine samples are subjected to deconjugation using ß-glucuronidase, followed by a solvent extraction procedure. Compounds are separated on a reverse-phase HPLC column within a 14 min cycle. Low assay limits are required in order to demonstrate prior exposure to SCs. Matrix effects were studied and proved to be significant for selected analytes, and were challenging to circumvent as isotope-labeled internal standards are not available. An elimination profile from a naïve user following a single smoke of "Kronic" was constructed, showing urinary excretion over 2-3 days with peak concentrations of different metabolites 3-16.5 h after smoking. This method has been developed to process several hundred samples within a high-throughput drugs of abuse laboratory, with growing evidence that the use of synthetic cannabinoid blends is common within the Australian workforce.


Assuntos
Canabinoides/urina , Cromatografia de Fase Reversa/métodos , Indóis/urina , Naftalenos/urina , Espectrometria de Massas em Tandem/métodos , Acetatos , Acetonitrilas , Austrália , Cromatografia Líquida de Alta Pressão/métodos , Drogas Desenhadas , Humanos , Drogas Ilícitas , Indóis/metabolismo , Modelos Lineares , Metanol , Naftalenos/metabolismo , Reprodutibilidade dos Testes
7.
J Assist Reprod Genet ; 28(2): 137-44, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21063765

RESUMO

PURPOSE: Assessment of embryo viability is a key component of in vitro fertilization (IVF) and currently relies largely on embryo morphology and cleavage rate. In this study, we used receiver operating characteristic (ROC) analysis to compare the Viability Score (generated by metabolomic profiling of spent embryo culture media using near infrared (NIR) spectroscopy) to morphologic grading for predicting pregnancy in women undergoing single embryo transfer (SET) on day 5. METHODS: A total of 198 spent embryo culture media samples were collected in four IVF centers located in the USA, Europe and Australia. First, 137 samples (training set) were analyzed by NIR to develop an algorithm that generates a Viability Score predictive of pregnancy for each sample. Next, 61 samples (validation set) were analyzed by observers blinded to embryo morphology and IVF outcome, using the Day 5 algorithm generated with the training set. Pregnancy was defined as fetal cardiac activity (FCA) at 12 weeks of gestation. RESULTS: The Area Under the Curve (AUC) was greater for the metabolomic Viability Score compared to Morphology [Training set: 0.75 versus 0.55, p = 0.0011; Validation set: 0.68 versus 0.50, P = 0.021], and for a Composite score (obtained using a model combining Viability Score with morphologic grading), compared to morphology alone [0.74 versus 0.50, p = 0.004]. CONCLUSIONS: Our findings suggest that Viability Score alone or in combination with morphologic grading has the potential to be a better classifier for pregnancy outcome than morphology alone in women undergoing SET on day 5.


Assuntos
Implantação do Embrião/fisiologia , Embrião de Mamíferos/anatomia & histologia , Fertilização in vitro , Metabolômica/estatística & dados numéricos , Curva ROC , Desenvolvimento Embrionário , Feminino , Humanos , Gravidez , Prognóstico , Transferência de Embrião Único
8.
Fertil Steril ; 84(6): 1620-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16359955

RESUMO

OBJECTIVE: To determine the extent to which embryo selection by blastulation and elective single blastocyst transfer, supported by efficient cryostorage of spare embryos, can reduce multiple pregnancies and maintain or improve on the live birth rate from IVF. DESIGN: Prospective, nonrandomized cohort study. SETTING: Sydney IVF, a private clinic in Australia. PATIENT(S): In vitro fertilization patients aged <38 years with three or more usable blastocyst, recruited from April 2000 through December 2001, with pregnancies followed up until August 2004. INTERVENTION(S): Blastocysts were cultured and cryostored with stage-specific culture medium and low oxygen conditions. MAIN OUTCOME MEASURE(S): Fetal heart-positive twin pregnancy rate and accumulating "take-home baby" rate per retrieval leading to blastocyst transfer. RESULT(S): Among 121 women who elected single fresh blastocyst transfer (but who could elect to have two frozen blastocysts transferred at once), 79 (65.3%) took home a baby, with a twin pregnancy rate of 7%. Among 285 women who chose two blastocysts for fresh transfer, 184 (64.2%) took home at least one baby, with a twin pregnancy rate of 34% and five perinatal deaths. CONCLUSION(S): With technically appropriate blastocyst culture and freezing, and elective single blastocyst transfer in the fresh cycle, the overall multiple pregnancy rate can be reduced by >75%, permitting in this series a slight increase in the chance of taking home a baby.


Assuntos
Blastômeros/citologia , Transferência Embrionária/estatística & dados numéricos , Fertilização in vitro/métodos , Resultado da Gravidez , Gravidez Múltipla/estatística & dados numéricos , Gêmeos , Adulto , Estudos de Coortes , Criopreservação , Feminino , Fertilização in vitro/estatística & dados numéricos , Humanos , Recém-Nascido , Idade Materna , Gravidez , Estudos Prospectivos
9.
Health Expect ; 7(4): 303-16, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15544683

RESUMO

BACKGROUND: Patients vary widely in their preferences and capacity for participating in treatment decision-making. There are few interventions targeting patient understanding of how doctors make decisions and shared decision-making. This randomized trial investigates the effects of providing cancer patients with a package designed to facilitate shared decision-making prior to seeing their oncologist. PATIENTS AND METHODS: Sixty-five female cancer patients were randomized to receive either the package (booklet and 15-min video) or a booklet on living with cancer, before their initial consultation. Participants completed questionnaires prior to the intervention, immediately after the oncology consultation, and 2 weeks and 6 months later. The first consultation with the oncologist was audio-taped and transcribed. RESULTS: Patients receiving the package were more likely than controls to declare their information and treatment preferences in the consultation, and their perspectives on the costs, side-effects and benefits of treatment. Doctors introduced considerably more new themes in the consultations with intervention subjects than they did with controls; no other differences in doctor behaviour were noted. CONCLUSIONS: This short intervention successfully shifted patient and doctor behaviour closer to the shared decision-making model, although it did not alter patients' preferences for information or involvement.


Assuntos
Tomada de Decisões , Neoplasias/psicologia , Educação de Pacientes como Assunto , Participação do Paciente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Feminino , Humanos , Pessoa de Meia-Idade , Relações Médico-Paciente , Estatísticas não Paramétricas , Inquéritos e Questionários , Materiais de Ensino
10.
Twin Res ; 6(6): 536-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14965466

RESUMO

As the success rates of IVF clinics improve, one of the adverse consequences is the increased incidence of twins, due largely to the number of embryos transferred. Even if the number of embryos transferred is restricted to two, the twinning rate can exceed 40% of the pregnancies. An obvious way to reduce this high twin rate would be to transfer only one embryo. This would require that cryopreservation of the supernumerary embryos be efficacious enough so that the chance of achieving an ongoing pregnancy is not diminished by transferring a single embryo in the stimulated cycle. Previous studies utilising embryos on day 2 and 3 of development have shown that the pregnancy rates can be acceptable (about 40%) and that the cumulative rate can be up to 60%. Most of these studies, however, do not include a comparison with the cumulative pregnancy rate with two embryos transferred in the stimulated cycle. Therefore, the efficacy has not been proven. We present clinical data from the past few years to illustrate the increase in success rates and the concomitant increase in twinning rates. The increased success in the cryopreservation program has enabled us to trial a single embryo transfer program and compare the results to the transfer of two embryos. The results strongly suggest that the transfer of a single embryo is the better clinical option.


Assuntos
Transferência Embrionária , Fertilização in vitro , Gravidez Múltipla , Embrião de Mamíferos , Serviços de Planejamento Familiar , Feminino , Fertilização in vitro/métodos , Humanos , Gravidez
11.
Health Expect ; 5(3): 236-45, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12199662

RESUMO

BACKGROUND: Patients vary widely in their preferences and capacity for participation in medical decision-making. This study aimed to document oncologist responses to more extreme presentations and identify helpful and unhelpful strategies for clinicians. PATIENTS AND METHODS: A trained actor played the role of a patient with early stage breast cancer who was attending her first consultation with a medical oncologist. She adopted in random order two different consultation participation styles: that of a very anxious, active patient, and that of a depressed, passive patient. Medical consultations between the actor and 16 medical oncologists were videotaped and then analysed qualitatively by two trained raters. RESULTS: Strategies that facilitated shared decision-making with both patient types and were positively endorsed by the actor/patient included explicit agenda-setting, active listening, checking understanding, endorsing question-asking, offering decisional delay, and non-verbal behaviours conveying empathy and warmth. Oncologists successfully negotiated with the active patient to share control of the consultation, and responded to emotional cues from the passive patient. Unhelpful strategies were also identified. CONCLUSIONS: Few clinicians receive training in responding to differing communication styles in their patients that could potentially cause conflict and hinder optimal treatment decision-making. This study suggests some useful strategies for oncologists to consider, to widen their behavioural repertoire in the cancer consultation.


Assuntos
Comunicação , Tomada de Decisões , Emoções , Neoplasias/psicologia , Participação do Paciente , Relações Médico-Paciente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Desempenho de Papéis , Gravação de Videoteipe
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