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1.
Br J Pharmacol ; 181(3): 375-392, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37605852

RESUMO

BACKGROUND AND PURPOSE: Development of core concepts in disciplines such as biochemistry, microbiology and physiology have transformed teaching. They provide the foundation for the development of teaching resources for global educators, as well as valid and reliable approaches to assessment. An international research consensus recently identified 25 core concepts of pharmacology. The current study aimed to define and unpack these concepts. EXPERIMENTAL APPROACH: A two-phase, iterative approach, involving 60 international pharmacology education experts, was used. The first phase involved drafting definitions for core concepts and identifying key sub-concepts via a series of online meetings and asynchronous work. These were refined in the second phase, through a 2-day hybrid workshop followed by a further series of online meetings and asynchronous work. KEY RESULTS: The project produced consensus definitions for a final list of 24 core concepts and 103 sub-concepts of pharmacology. The iterative, discursive methodology resulted in modification of concepts from the original study, including change of 'drug-receptor interaction' to 'drug-target interaction' and the change of the core concept 'agonists and antagonists' to sub-concepts of drug-target interaction. CONCLUSIONS AND IMPLICATIONS: Definitions and sub-concepts of 24 core concepts provide an evidence-based foundation for pharmacology curricula development and evaluation. The next steps for this project include the development of a concept inventory to assess acquisition of concepts, as well as the development of case studies and educational resources to support teaching by the global pharmacology community, and student learning of the most critical and fundamental concepts of the discipline.


Assuntos
Currículo , Farmacologia , Humanos
2.
Pharmacol Res Perspect ; 9(6): e00894, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34817122

RESUMO

Pharmacology education currently lacks a research-based consensus on which core concepts all graduates should know and understand, as well as a valid and reliable means to assess core conceptual learning. The Core Concepts in Pharmacology Expert Group (CC-PEG) from Australia and New Zealand recently identified a set of core concepts of pharmacology education as a first step toward developing a concept inventory-a valid and reliable tool to assess learner attainment of concepts. In the current study, CC-PEG used established methodologies to define each concept and then unpack its key components. Expert working groups of three to seven educators were formed to unpack concepts within specific conceptual groupings: what the body does to the drug (pharmacokinetics); what the drug does to the body (pharmacodynamics); and system integration and modification of drug-response. First, a one-sentence definition was developed for each core concept. Next, sub-concepts were established for each core concept. These twenty core concepts, along with their respective definitions and sub-concepts, can provide pharmacology educators with a resource to guide the development of new curricula and the evaluation of existing curricula. The unpacking and articulation of these core concepts will also inform the development of a pharmacology concept inventory. We anticipate that these resources will advance further collaboration across the international pharmacology education community to improve curricula, teaching, assessment, and learning.


Assuntos
Currículo , Farmacologia/educação , Austrália , Comportamento Cooperativo , Humanos , Aprendizagem , Nova Zelândia , Ensino/organização & administração
3.
Pharmacol Res Perspect ; 9(4): e00836, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34288559

RESUMO

Pharmacology education currently lacks an agreed knowledge curriculum. Evidence from physics and biology education indicates that core concepts are useful and effective structures around which such a curriculum can be designed to facilitate student learning. Building on previous work, we developed a novel, criterion-based method to identify the core concepts of pharmacology education. Five novel criteria were developed, based on a literature search, to separate core concepts in pharmacology from topics and facts. Core concepts were agreed to be big ideas, enduring, difficult, applicable across contexts, and useful to solve problems. An exploratory survey of 33 pharmacology educators from Australia and New Zealand produced 109 terms, which were reduced to a working list of 26 concepts during an online workshop. Next, an expert group of 12 educators refined the working list to 19 concepts, by applying the five criteria and consolidating synonyms, and added three additional concepts that emerged during discussions. A confirmatory survey of a larger group resulted in 17 core concepts of pharmacology education. This list may be useful for educators to evaluate existing curricula, design new curricula, and to inform the development of a concept inventory to test attainment of the core concepts in pharmacology.


Assuntos
Currículo , Farmacologia/educação , Austrália , Técnica Delfos , Docentes , Humanos , Nova Zelândia , Inquéritos e Questionários
4.
Anticancer Agents Med Chem ; 21(11): 1413-1430, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32972351

RESUMO

BACKGROUND: The effect of cruciferous vegetable intake on breast cancer survival is controversial at present. Glucosinolates are the naturally occurring constituents found across the cruciferous vegetables. Isothiocyanates are produced from the hydrolysis of glucosinolates and this reaction is catalysed by the plant-derived enzyme myrosinase. The main Isothiocyanates (ITCs) from cruciferous vegetables are sulforaphane, benzyl ITC, and phenethyl ITC, which had been intensively investigated over the last decade for their anti-breast cancer effects. OBJECTIVE: The aim of this article is to systematically review the evidence from all types of studies, which examined the protective effect of cruciferous vegetables and/or their isothiocyanate constituents on breast cancer. METHODS: A systematic review was conducted in Pubmed, EMBASE, and the Cochrane Library from inception to 27 April 2020. Peer-reviewed studies of all types (in vitro studies, animal studies, and human studies) were selected. RESULTS: The systematic literature search identified 16 human studies, 4 animal studies, and 65 in vitro studies. The effect of cruciferous vegetables and/or their ITCs intake on breast cancer survival was found to be controversial and varied greatly across human studies. Most of these trials were observational studies conducted in specific regions, mainly in the US and China. Substantial evidence from in vitro and animal studies was obtained, which strongly supported the protective effect of sulforaphane and other ITCs against breast cancer. Evidence from in vitro studies showed that sulforaphane and other ITCs reduced cancer cell viability and proliferation via multiple mechanisms and pathways. Isothiocyanates inhibited cell cycle, angiogenesis and epithelial mesenchymal transition, as well as induced apoptosis and altered the expression of phase II carcinogen detoxifying enzymes. These are the essential pathways that promote the growth and metastasis of breast cancer. Noticeably, benzyl ITC showed a significant inhibitory effect on breast cancer stem cells, a new dimension of chemo-resistance in breast cancer treatment. Sulforaphane and other ITCs displayed anti-breast cancer effects at variable range of concentrations and benzyl isothiocyanate appeared to have a relatively lower inhibitory concentration IC50. The mechanisms underlying the cancer protective effect of sulforaphane and other ITCs have also been highlighted in this article. CONCLUSION: Current preclinical evidence strongly supports the role of sulforaphane and other ITCs as potential therapeutic agents for breast cancer, either as adjunct therapy or combined therapy with current anti-breast cancer drugs, with sulforaphane displaying the greatest potential.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Isotiocianatos/farmacologia , Substâncias Protetoras/farmacologia , Verduras/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Isotiocianatos/química , Isotiocianatos/isolamento & purificação , Estrutura Molecular , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação
5.
Methods Mol Biol ; 952: 7-34, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23100222

RESUMO

Peroxisome proliferator-activated receptor α (PPARα) is a member of the nuclear/steroid receptor gene superfamily that also comprises ß, δ, and γ isoforms. PPARα is a ligand-activated transcription factor that plays an important role in the regulation of many genes involved in key metabolic processes. Today, PPARα has been cloned from mammalian, marsupial, and a number of marine species and its expression has been found to be relatively tissue- and species-specific. Here, we describe the methods for cloning of PPARα genes by RT-PCR and RACE approaches and related protocols for studying the expression of cloned PPARα cDNAs in mammalian cell systems.


Assuntos
Clonagem Molecular/métodos , Regulação da Expressão Gênica , PPAR alfa/genética , Animais , Células COS , Núcleo Celular/metabolismo , Chlorocebus aethiops , Citosol/metabolismo , DNA Complementar/biossíntese , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Humanos , Camundongos , Plasmídeos/genética , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência
6.
Epilepsy Behav ; 26(1): 64-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23220461

RESUMO

There have been considerable debates about bioequivalence and generic substitution of certain critical care drugs. We aimed to understand patient attitudes and perceptions about generic substitution in the treatment of epilepsy. In this pilot study, a self-administered anonymous survey was completed by 47 patients with epilepsy. The response rate by postal mail was 6.7%. More than 70% of the patients were concerned about the effectiveness of generic antiepileptic drugs, and 68% of the patients were not comfortable receiving generics to treat their epilepsy. About 87% of the patients thought that their antiepileptic drug should only be substituted with a generic with their consent, and 64% of the patients believed that substitution should only take place with the consent of their doctor. Considerable concern exists among patients about generic substitution in the treatment of epilepsy. More data regarding whether generic antiepileptic drugs are bioequivalent in clinical situations would help to address patient concerns.


Assuntos
Anticonvulsivantes/uso terapêutico , Atitude Frente a Saúde , Substituição de Medicamentos , Epilepsia/tratamento farmacológico , Epilepsia/psicologia , Percepção , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Equivalência Terapêutica , Adulto Jovem
7.
Gene ; 506(2): 423-8, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22759518

RESUMO

Australian marsupials are unique fauna that have evolved and adapted to unique environments and thus it is likely that their detoxification systems differ considerably from those of well-studied eutherian mammals. Knowledge of these processes in marsupials is therefore vital to understanding the consequences of exposure to xenobiotics. Cytochromes P450 (CYPs) are critically important in the oxidative metabolism of a diverse array of both xenobiotics and endogenous substrates. In this study we have cloned and characterized CYP3A70, the first identified member of the CYP3A gene subfamily from Eastern gray kangaroo (Macropus giganteus). A 1665 base pair kangaroo hepatic CYP3A complete cDNA, designated CYP3A70, was cloned by reverse transcription-polymerase chain reaction approaches, which encodes a protein of 506 amino acids. The CYP3A70 cDNA shares approximately 71% nucleotide and 65% amino acid sequence homology to human CYP3A4 and displays high sequence similarity to other published mammalian CYP3As from human, monkey, cow, pig, dog, rat, rabbit, mouse, hamster, and guinea pig. Transfection of the CYP3A70 cDNAs into 293T cells resulted in stable cell lines expressing a CYP3A immuno-reactive protein that was recognized by a goat anti-human CYP3A4 polyclonal antibody. The anti-human CYP3A4 antibody also detected immunoreactive proteins in liver microsomes from all test marsupials, including the kangaroo, koala, wallaby, and wombat, with multiple CYP3A immunoreactive bands observed in kangaroo and wallaby tissues. Relatively, very low CYP catalytic activity was detected for the kangaroo CYP3A70 cDNA-expressed proteins (19.6 relative luminescent units/µg protein), which may be due to low protein expression levels. Collectively, this study provides primary molecular data regarding the Eastern kangaroo hepatic CYP3A70 gene and enables further functional analyses of CYP3A enzymes in marsupials.


Assuntos
Citocromo P-450 CYP3A/química , Citocromo P-450 CYP3A/genética , Regulação da Expressão Gênica , Animais , Linhagem Celular , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/metabolismo , Feminino , Humanos , Fígado/metabolismo , Macropodidae , Masculino , Marsupiais/genética , Modelos Genéticos , Isoformas de Proteínas , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Especificidade da Espécie
8.
Gene ; 2011 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-21888957

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

9.
Crit Rev Food Sci Nutr ; 51(10): 946-54, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21955093

RESUMO

Colorectal cancer is the second leading cause of cancer death in Australia. Nutrition, particularly intake of vegetables and certain plant components, has been reported to have a major role in cancer risk reduction. Recently, there has been a growing research interest in rosemary, a common household plant grown in many parts of the world. This study aims to review scientific evidence from all studies, published from 1996 to March 2010 that examined the protective effects of rosemary on colorectal cancer and other types of cancer. Literature evidence from animal and cell culture studies demonstrates the anticancer potential of rosemary extract, carnosol, carnosic acid, ursolic acid, and rosmarinic acid. No evidence for other rosemary constituents was found. The reported anticancer properties were found to arise through the molecular changes in the multiple-stage process of cancer development, which are dose related and not tissue or species specific. This is evidenced by the ability of rosemary to suppress the development of tumors in several organs including the colon, breast, liver, stomach, as well as melanoma and leukemia cells. The results suggested that the different molecular targets modulated by rosemary and its active constituents are useful indicators of success in clinical cancer chemo-prevention trials.


Assuntos
Anticarcinógenos/farmacologia , Neoplasias Colorretais/prevenção & controle , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos , Modelos Animais , Óleos Voláteis/química , Rosmarinus/química , Células Tumorais Cultivadas/efeitos dos fármacos
10.
Comp Biochem Physiol C Toxicol Pharmacol ; 154(4): 367-76, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21807118

RESUMO

Cytochromes P450 (CYPs) are critically important in the oxidative metabolism of a diverse array of xenobiotics and endogenous substrates. Previously, we cloned and characterised the CYP2C, CYP4A, and CYP4B gene subfamilies from marsupials and demonstrated important species-differences in both activity and tissue expression of these CYP enzymes. Recently, we isolated the Eastern grey kangaroo CYP3A70. Here we have cloned and characterised the second identified member of marsupial CYP3A gene subfamily, CYP3A78 from the koala (Phascolarctos cinereus). In addition, we have examined the gender-differences in microsomal erythromycin N-demethylation activity (a CYP3A marker) and CYP3A protein expression across test marsupial species. Significant differences in hepatic erythromycin N-demethylation activity were observed between male and female koalas, with the activity detected in female koalas being 2.5-fold higher compared to that in male koalas (p<0.01). No gender-differences were observed in tammar wallaby or Eastern grey kangaroo. Immunoblot analysis utilising anti-human CYP3A4 antibody detected immunoreactive proteins in liver microsomes from all test male and female marsupials including the koala, tammar wallaby, and Eastern grey kangaroo, with no gender-differences detected across test marsupials. A 1610 bp koala hepatic CYP3A complete cDNA, designated CYP3A78, was cloned by reverse transcription-polymerase chain reaction approaches. It displays 64% nucleotide and 57% amino acid sequence identity to the Eastern grey kangaroo CYP3A70. The CYP3A78 cDNA encodes a protein of 515 amino acids, shares approximately 68% nucleotide and 56% amino acid sequence identity to human CYP3A4, and displays high sequence similarity to other published mammalian CYP3As from human, monkey, cow, pig, dog, rat, rabbit, mouse, hamster, and guinea pig. Collectively, this study provides primary molecular data regarding koala hepatic CYP3A78 gene and enables further functional analyses of CYP3A enzymes in marsupials. Given the significant role that CYP3A enzymes play in the metabolism of both endogenous and exogenous compounds, the clone provides an important step in elucidating the metabolic capacity of marsupials.


Assuntos
Citocromo P-450 CYP3A/genética , Phascolarctidae/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Citocromo P-450 CYP3A/metabolismo , Feminino , Humanos , Masculino , Marsupiais/genética , Microssomos Hepáticos/enzimologia , Dados de Sequência Molecular , Alinhamento de Sequência , Especificidade da Espécie
11.
Artigo em Inglês | MEDLINE | ID: mdl-20826229

RESUMO

Cytochromes P450 (CYPs) are critically important in the oxidative metabolism of a diverse array of xenobiotics and endogenous substrates. We have previously reported the cloning and characterisation of the koala CYP4A15, the first reported member of the CYP4 family from marsupials, and have demonstrated important species differences in CYP4A activity and tissue expression. In the present study, the cloning of CYP4B1 in the wallaby (Macropus eugenii) and their expression across marsupials is described. Rabbit anti-mouse CYP4B1 antibody detected immunoreactive proteins in lung and liver microsomes from all test marsupials, with relative weak signal detected from the koala, suggesting a species-specific expression. Microsomal 2-aminofluorene bio-activation (a CYP4B1 marker) in wallaby lung was comparable to that of rabbit, with significant higher activities detected in wallaby liver and kidneys compared to rabbit. A 1548bp wallaby lung CYP4B complete cDNA, designated CYP4B1, which encodes a protein of 510 amino acids and shares 72% nucleotide and 69% amino acid sequence identity to human CYP4B1, was cloned by polymerase chain reaction approaches. The results demonstrate the presence of wallaby CYP4B1 that shares several common features with other published CYP4Bs; however the wallaby CYP4B1 cDNA contains four extra amino acid residues at the NH2-terminal, a fundamentally conserved transmembrane anchor of all eukaryote CYPs.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Pulmão/enzimologia , Macropodidae/metabolismo , Sequência de Aminoácidos , Animais , Hidrocarboneto de Aril Hidroxilases/genética , DNA Complementar/isolamento & purificação , Fluorenos/metabolismo , Immunoblotting , Rim/enzimologia , Fígado/enzimologia , Microssomos/enzimologia , Dados de Sequência Molecular , Coelhos
12.
Int J Pharm Pract ; 18(4): 245-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20636678

RESUMO

OBJECTIVES: Amiodarone is a low-solubility, high-permeability drug with a narrow therapeutic index and reported bioavailability problems associated with switching formulations. The aim of this study was to identify whether there is variability in drug release and physical characteristics of different commercially available amiodarone hydrochloride formulations in Australia. METHODS: Four available formulations (innovator Cordarone (COR) and generic products G1, G2 and G3) were tested for drug dissolution, content uniformity, hardness, weight variation, friability and disintegration in accordance with the US Pharmacopeia specifications. KEY FINDINGS: The tested formulations exhibited variable dissolution behaviours: G1 and G3 exhibited the fastest dissolution, G2 dissolution was the slowest and Cordarone showed a medium dissolution. After 3 months' exposure to high temperature (40 +/- 2 degrees C) and relative humidity (75 +/- 5%), the products exhibited a higher degree of disparity, with drug-release profiles of the generics being markedly different from that of Cordarone. This suggests possible implications on bioequivalence for patients who live in warm/tropical regional areas. Most products met the US Pharmacopeia specifications for drug-content uniformity and other test physical characteristics. CONCLUSIONS: The results suggested that variability in drug release profiles in vitro of amiodarone formulations might be a potential indicator of compromised bioavailability, causing possible interference with the therapeutic response of the drug.


Assuntos
Amiodarona/administração & dosagem , Antiarrítmicos/administração & dosagem , Medicamentos Genéricos/administração & dosagem , Amiodarona/química , Amiodarona/farmacocinética , Antiarrítmicos/química , Antiarrítmicos/farmacocinética , Austrália , Disponibilidade Biológica , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Medicamentos Genéricos/química , Medicamentos Genéricos/farmacocinética , Dureza , Umidade , Farmacopeias como Assunto , Solubilidade , Comprimidos , Temperatura , Estados Unidos
13.
Int J Pharm Pract ; 18(1): 63-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20405598

RESUMO

OBJECTIVES: The aim was to investigate patients' perceptions and understanding on the appropriate use of non-prescription ibuprofen. METHODS: In this pilot study, a self-administered anonymous survey was completed by 183 patients presenting at one of the eight selected community pharmacy premises in South Australia and the Northern Territory during the study. The questionnaire comprised items on: demographics (age, gender), current medications, frequency of ibuprofen use, medical consultations, reading manufacturer's printed dosage/warning instructions, sources from which drug information was gathered and understanding of common indications for ibuprofen. KEY FINDINGS: Sixty per cent of patients (n = 110/183), predominantly females, were currently on other medications and 64.5% of patients (n = 118/183) did not seek medical advice before using non-prescription ibuprofen. Seventy-one per cent (n = 130) of these patients had used ibuprofen for more than a year. The majority of patients did not provide precise answers for the common indications of ibuprofen. Sixty-six per cent of patients (n = 110) reported rarely or never reading manufacturer's printed warning instructions on the potential drug interactions or adverse effects associated with the use of the product. CONCLUSIONS: Many patients are unaware that non-presciption analgesics such as ibuprofen can cause potentially serious adverse effects when used in combination with other common medications.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Ibuprofeno/administração & dosagem , Medicamentos sem Prescrição/administração & dosagem , Pacientes/psicologia , Autoadministração/estatística & dados numéricos , Adolescente , Adulto , Idoso , Anti-Inflamatórios não Esteroides/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
14.
J Pharm Pharmacol ; 61(8): 1037-42, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19703347

RESUMO

OBJECTIVES: This study examined the effects of St John's wort (Hypericum perforatum) on the disposition of fexofenadine, a substrate of P-glycoprotein/organic anion transporting polypeptide, in the isolated perfused rat liver. METHODS: Male Sprague-Dawley rats were given St John's wort, 1000 mg/kg, by intragastric gavage once daily for 14 days. On day 15, livers were isolated surgically and perfused in a recirculating system with fexofenadine (2 microg/ml), either alone or following addition of ciclosporin (0.5 microg/ml) 5 min before the addition of fexofenadine. Perfusate samples and bile were collected for 60 min. Fexofenadine in perfusate, bile and the homogenised livers was measured by HPLC. KEY FINDINGS: Administration of St John's wort significantly increased biliary clearance with respect to perfusate and biliary clearance with respect to the concentration in the liver, by 74% and 71%, respectively. This was reversed by ciclosporin. CONCLUSIONS: St John's wort enhanced the elimination of fexofenadine into the bile. This could be because it increases the activity of P-glycoprotein on the canalicular membrane of hepatocytes.


Assuntos
Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacocinética , Hypericum/química , Extratos Vegetais/farmacologia , Terfenadina/análogos & derivados , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Ciclosporina/farmacologia , Interações Medicamentosas , Hepatócitos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Terfenadina/farmacocinética
15.
Artigo em Inglês | MEDLINE | ID: mdl-19444989

RESUMO

The cloning, expression and characterization of hepatic NADPH-cytochrome P450 reductase (CPR) from koala (Phascolarctos cinereus) is described. Two 2059 bp koala liver CPR cDNAs, designated CPR1 and CPR2, were cloned by reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends. The koala CPR cDNAs encode proteins of 678 amino acids and share 85% amino acid sequence identity to human CPR. Transfection of the koala CPR cDNAs into Cos-7 cells resulted in the expression of proteins, which were recognized by a goat-antihuman CPR antibody. The koala CPR1 and 2 cDNA-expressed enzymes catalysed cytochrome c reductase at the rates of 4.9 +/- 0.5 and 2.6 +/- 0.4 nmol/min/mg protein (mean +/- SD, n = 3), respectively which were comparable to that of rat CPR cDNA-expressed enzyme. The apparent Km value for CPR activity in koala liver microsomes was 11.61 +/- 6.01 microM, which is consistent with that reported for rat CPR enzyme. Northern analysis detected a CPR mRNA band of approximately 2.6 kb. Southern analysis suggested a single PCR gene across species. The present study provides primary molecular data regarding koala CPR1 and CPR2 genes in this unique marsupial species.


Assuntos
Clonagem Molecular , Regulação Enzimológica da Expressão Gênica/fisiologia , Microssomos Hepáticos/enzimologia , NADPH-Ferri-Hemoproteína Redutase/biossíntese , NADPH-Ferri-Hemoproteína Redutase/genética , Phascolarctidae/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular/métodos , Humanos , Macropodidae , Masculino , Dados de Sequência Molecular , Ratos , Ratos Wistar
16.
Artigo em Inglês | MEDLINE | ID: mdl-18619561

RESUMO

Cytochromes P450 (CYPs) are critically important in the oxidative metabolism of a diverse array of xenobiotics and endogenous substrates. We have previously reported that the obligate Eucalyptus feeder koala (Phascolarctos cinereus) exhibits a higher hepatic CYP2C activity as compared to non-Eucalyptus feeders human or rat, with stimulation of CYP2C activity by cineole. In the present study, we examine CYP2C expression by immunohistochemistry and describe the identification and cloning of koala CYP2Cs. Utilising anti-rat CYP2C6 antibody, the expression of CYP2C was found to be uniform across the hepatic sections, being consistent with that observed in human and rat. Two 1647 and 1638 bp koala liver CYP2C complete cDNAs, designated CYP2C47 and CYP2C48 respectively, were cloned by cDNA library screening. The koala CYP2C cDNAs encode a protein of 495 amino acids. Three additional partial CYP2C sequences were also identified from the koala, indicating the multiplicity of the CYP2C subfamily in this unique marsupial species. The results of this study demonstrate the presence of koala hepatic CYP2Cs that share several common features with other published CYP2Cs; however CYP2C47 and CYP2C48 contain four extra amino acid residues at the NH2-terminal, a transmembrane anchor which was reported being a fundamentally conserved structure core of all eukaryote CYP enzymes.


Assuntos
Sistema Enzimático do Citocromo P-450/isolamento & purificação , Fígado/enzimologia , Phascolarctidae , Sequência de Aminoácidos , Animais , Sequência de Bases , Feminino , Masculino , Dados de Sequência Molecular , Ratos , Ratos Wistar
17.
J Nutr ; 137(10): 2264-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17885009

RESUMO

Colorectal cancer (CRC) is the 3rd leading cause of cancer death in the United States and the 2nd leading cause of cancer death in Australia. Environmental factors play important roles in the multiple-stage process of CRC and nutritional intervention has been identified as playing a major role in its prevention. The aim of this study was to review systematically the scientific evidence from all studies conducted over the last decade that examined effects of garlic on CRC. Levels of evidence were ranked from level I to level V according to study designs and the quality of each study was assessed against a set of quality criteria based on those used by the National Health and Medical Research Council in Australia. One randomized controlled trial (RCT, level II) reported a statistically significant 29% reduction in both size and number of colon adenomas in CRC patients taking aged garlic extract. Five of 8 case control/cohort studies (level III) suggested a protective effect of high intake of raw/cooked garlic and 2 of 8 of these studies suggested a protective effect for distal colon. A published meta-analysis (level III) of 7 of these studies confirmed this inverse association, with a 30% reduction in relative risk. Eleven animal studies (level V) demonstrated a significant anticarcinogenic effect of garlic and/or its active constituents. On balance, there is consistent scientific evidence derived from RCT of animal studies reporting protective effects of garlic on CRC despite great heterogeneity of measures of intakes among human epidemiological studies.


Assuntos
Neoplasias Colorretais/prevenção & controle , Alho , Alho/química , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Fatores de Risco
18.
Clin Exp Pharmacol Physiol ; 33(8): 685-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16895540

RESUMO

1. The aim of the present study was to examine the effect of bacterial lipopolysaccharide (LPS) on the disposition of an organic anion transporting polypeptide and P-glycoprotein substrate in the rat isolated perfused liver. 2. Male Sprague-Dawley rats were divided into four groups. Three of the groups received 1, 2.5 or 5 mg/kg, i.p., Escherichia coli LPS in sterile saline. The fourth group received an equivalent volume of sterile saline i.p. Twenty-four hours after treatment, rats were anaesthetized and the liver isolated and perfused with fexofenadine at an initial concentration of 2000 ng/mL in a recirculating system. Perfusate and bile samples were collected for 60 min and the liver was collected at the end of the perfusion. Fexofenadine concentrations were determined by HPLC. Fexofenadine pharmacokinetic parameters, the final liver : perfusate (L : P) and bile : liver (B : L) concentration ratios were determined. 3. Injection of LPS changed the hepatic disposition of fexofenadine. The changes were most marked in the 5 mg/kg LPS group. Notably, clearance from the perfusate (CL) and into the bile (CLB; 5.9 +/- 0.6 and 1.24 +/- 0.20 mL/min, respectively), L : P (44 +/- 11) and B : L (17 +/- 2) were all reduced (P < 0.05) in this group compared with control (CL 10.0 +/- 1.1 mL/min; CLB 2.7 +/- 0.5 mL/min; L : P 87 +/- 14; and B : L 30 +/- 4). 4. In conclusion CL and CLB were reduced following treatment with LPS in a manner consistent with downregulation of both canalicular and sinusoidal transport.


Assuntos
Sistema Biliar/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos H1/metabolismo , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , Terfenadina/análogos & derivados , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Bile/metabolismo , Sistema Biliar/metabolismo , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Cinética , Lipopolissacarídeos/administração & dosagem , Fígado/metabolismo , Masculino , Taxa de Depuração Metabólica , Transportadores de Ânions Orgânicos/metabolismo , Perfusão , Ratos , Ratos Sprague-Dawley , Terfenadina/metabolismo
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