RESUMO
Dasotraline is a dopamine and norepinephrine reuptake inhibitor, and the early clinical trials show a slow absorption and long elimination half-life. To investigate the absorption, distribution, metabolism, and excretion of dasotraline in humans, a single dose of [14C]-dasotraline was administered to eight healthy male adult volunteers. At 35 days, 90.7% of the dosed radioactivity was recovered in the urine (68.3%) and feces (22.4%). The major metabolic pathways involved were: (1) amine oxidation to form oxime M41 and sequential sulfation to form M42 or glucuronidation to form M43; (2) N-hydroxylation and sequential glucuronidation to form M35; (3) oxidative deamination to form (S)-tetralone; (4) mono-oxidation of (S)-tetralone and sequential glucuronidation to form M31A and M32; and (5) N-acetylation to form (1R,4S)-acetamide M102. A total of 8 metabolites were detected and structurally elucidated with 4 in plasma (M41, M42, M43, and M35), 7 in urine (M41, M42, M43, M31A, M32, M35, and (S)-tetralone), and 3 in feces (M41, (S)-tetralone, and (1R,4S)-acetamide). The 2 most abundant circulating metabolites were sulfate (M42) and glucuronide (M43) conjugates of the oxime of dasotraline, accounting for 60.1% and 15.0% of the total plasma radioactivity, respectively; unchanged dasotraline accounted for 8.59%. The oxime M41 accounted for only 0.62% of the total plasma radioactivity and was detected only at early time points. M35 was a minor glucuronide metabolite, undetectable by radioactivity but identified by mass spectrometry. The results demonstrate that dasotraline was slowly absorbed, and extensively metabolized by oxidation and subsequent phase II conjugations. The findings from this study also demonstrated that metabolism of dasotraline by humans did not produce metabolites that may cause a safety concern.
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Limited data are available on the prevalence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in the UK. We tested 124 raw meat samples for MRSA including pork (n = 63), chicken (n = 50) and turkey (n = 11) collected from retail outlets in North West England between March and July 2015. MRSA was recovered from nine (7·3%) samples (four chicken, three pork and two turkey) from different butchers and supermarkets. Four were labelled of UK origin, three were from continental Europe; the origin was not specified for two samples. Whole-genome sequencing (WGS), spa typing and the presence of lineage-specific canonical single nucleotide polymorphisms confirmed that they belonged to the livestock-associated clade of clonal complex (CC) 398. Seven (77·8%) isolates were multi-drug resistant. Phylogenetic analyses showed the isolates were diverse, suggesting multiple silent introductions of LA-MRSA into the UK food chain. Two chicken meat isolates belonged to a sub-clade recently reported from human cases in Europe where poultry meat was the probable source. The low levels of MRSA identified (<20 CFU per g) and absence of enterotoxin genes suggest the risk of acquisition of, or food-poisoning due to, LA-MRSA is low. Nevertheless, the MRSA contamination rate is higher than previously estimated; further evaluation of the public health impacts of LA-MRSA is warranted. SIGNIFICANCE AND IMPACT OF THE STUDY: Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is a public health concern worldwide, but has only been reported sporadically in the UK. In the largest UK study to date, samples of raw meat at retail sale were examined for both the presence and levels of MRSA. We report the first isolations of CC398 LA-MRSA from poultry meat in the UK including representatives of a particular sub-clade associated with cases of human infection/colonization in Europe. Although levels were low (<20 CFU per g), the contamination rate was higher than previous UK studies. Moreover, whole-genome sequencing revealed multiple independent introductions of LA-MRSA into the UK food chain.
Assuntos
Contaminação de Alimentos/análise , Contaminação de Alimentos/legislação & jurisprudência , Gado/microbiologia , Carne/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Animais , Galinhas , Inglaterra , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Filogenia , Infecções Estafilocócicas/microbiologia , Suínos , PerusRESUMO
Estrogen acts through two molecularly distinct receptors termed estrogen receptor alpha (ERα) and estrogen receptor beta (ERß) which bind estradiol with similar affinities and mediate the effects of estrogen throughout the body. ERα plays a major role in reproductive physiology and behavior, and mediates classic estrogen signaling in such tissues as the uterus, mammary gland, and skeleton. ERß, however, modulates estrogen signaling in the ovary, the immune system, prostate, gastrointestinal tract, and hypothalamus, and there is some evidence that ERß can regulate ERα activity. Moreover, ERß knockout studies and receptor distribution analyses in the CNS suggest that this receptor may play a role in the modulation of mood and cognition. In recent years several ERß-specific compounds (selective estrogen receptor beta modulators; SERM-beta) have become available, and research suggests potential utility of these compounds in menopausal symptom relief, breast cancer prevention, diseases that have an inflammatory component, osteoporosis, cardiovascular disease, and inflammatory bowel disease, as well as modulation of mood, and anxiety. Here we demonstrate an antidepressant-like effect obtained using two SERM-beta compounds, SERM-beta1 and SERM-beta2. These compounds exhibit full agonist activity at ERß in a cell based estrogen response element (ERE) transactivation assay. SERM-beta1 and 2 are non-proliferative with respect to breast as determined using the MCF-7 breast cancer cell-based assay and non-proliferative in the uterus as determined by assessing the effects of SERM-beta compounds on immature rat uterine weight and murine uterine weight. In vivo SERM-beta1 and 2 are brain penetrant and display dose dependent efficacy in the murine dorsal raphe assays for induction of tryptophan hydroxylase mRNA and progesterone receptor protein. These compounds show activity in the murine forced swim test and promote hippocampal neurogenesis acutely in rats. Taken together these data suggest that ERß may play an important role in modulating mood and the ERß specific compounds described herein will be useful tools for probing the utility of an ERß agonist for treating neuroendocrine-related mood disturbance and menopausal symptoms.
Assuntos
Antidepressivos , Receptor beta de Estrogênio/efeitos dos fármacos , RNA Mensageiro/biossíntese , Núcleos da Rafe/enzimologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Natação/psicologia , Triptofano Hidroxilase/biossíntese , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA/genética , Relação Dose-Resposta a Droga , Receptor alfa de Estrogênio/efeitos dos fármacos , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/crescimento & desenvolvimento , Humanos , Imuno-Histoquímica , Hibridização In Situ , Neurogênese/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Plasmídeos/genética , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/metabolismo , Receptores de Progesterona/metabolismo , Ativação Transcricional/efeitos dos fármacos , Triptofano Hidroxilase/genética , Útero/anatomia & histologia , Útero/fisiologiaRESUMO
Age-related sarcopenia results in frailty and decreased mobility, which are associated with increased falls and long-term disability in the elderly. Given the global increase in lifespan, sarcopenia is a growing, unmet medical need. This report aims to systematically characterize muscle aging in preclinical models, which may facilitate the development of sarcopenia therapies. Naïve rats and mice were subjected to noninvasive micro X-ray computed tomography (micro-CT) imaging, terminal in situ muscle function characterizations, and ATPase-based myofiber analysis. We developed a Definiens (Parsippany, NJ)-based algorithm to automate micro-CT image analysis, which facilitates longitudinal in vivo muscle mass analysis. We report development and characterization of translational in situ skeletal muscle performance assay systems in rat and mouse. The systems incorporate a custom-designed animal assay stage, resulting in enhanced force measurement precision, and LabVIEW (National Instruments, Austin, TX)-based algorithms to support automated data acquisition and data analysis. We used ATPase-staining techniques for myofibers to characterize fiber subtypes and distribution. Major parameters contributing to muscle performance were identified using data mining and integration, enabled by Labmatrix (BioFortis, Columbia, MD). These technologies enabled the systemic and accurate monitoring of muscle aging from a large number of animals. The data indicated that longitudinal muscle cross-sectional area measurement effectively monitors change of muscle mass and function during aging. Furthermore, the data showed that muscle performance during aging is also modulated by myofiber remodeling factors, such as changes in myofiber distribution patterns and changes in fiber shape, which affect myofiber interaction. This in vivo muscle assay platform has been applied to support identification and validation of novel targets for the treatment of sarcopenia.
Assuntos
Envelhecimento/fisiologia , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/patologia , Fibras Musculares Esqueléticas/fisiologia , Sarcopenia/fisiopatologia , Adenosina Trifosfatases/metabolismo , Envelhecimento/metabolismo , Animais , Estudos Longitudinais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Fibras Musculares Esqueléticas/metabolismo , Ratos , Ratos Sprague-Dawley , Sarcopenia/metabolismo , Tomografia Computadorizada por Raios X/métodosRESUMO
Actualmente, las personas con dificultades de aprendizaje viven más tiempo. Esta longevidad conlleva la aparición de enfermedades relacionadas con la edad, entre ellas la demencia. En personas de la población general con demencia no hay un buen reconocimiento y tratamiento del dolor1-4. La investigación llevada a cabo sobre las necesidades de tratamiento del dolor en personas con dificultades de aprendizaje y demencia es limitada, aunque estos pacientes presentarán un alto nivel de necesidades de salud física que, como consecuencia, se traducirán en dolor5,6. En el estudio de investigación Respuesta a las necesidades derivadas del dolor en personas con dificultades de aprendizaje y demencia7, se exploró la detección, el tratamiento y la comprensión del dolor en una serie de grupos profesionales implicados en la asistencia a personas con dificultades de aprendizaje y demencia. En dicho estudio también se registraron las experiencias y las opiniones de algunas personas con dificultades de aprendizaje y demencia. Se examinaron las disyuntivas y los obstáculos para el tratamiento eficaz del dolor, y descubrieron que las experiencias y el tratamiento del dolor en personas con dificultades de aprendizaje y demencia eran similares a los datos obtenidos en la población general. No obstante, en la investigación se identificaron cuestiones adicionales y agravantes relacionadas con las personas con dificultades de aprendizaje. A partir de esta investigación, en este artículo se resumen las recomendaciones para médicos y proveedores de servicios, y se tratan las lecciones principales para responder de la manera más eficaz al dolor de personas con síndrome de Down y demencia (AU)
People with a learning disability are living longer. This increased longevity brings with it the conditions of older age including dementia. Amongst people in the general population who have dementia there is inadequate pain recognition and treatment1-4. Limited research has been undertaken on the pain management needs of people with a learning disability who have dementia, yet they will experience high levels of physical health needs that will, as a consequence, result in pain5,6. The research study Responding to the Pain needs of People with a Learning Disability and Dementia7 explored the detection, management and understanding of pain amongst a range of professional groups involved in supporting people with a learning disability who have dementia. The study also recorded the experiences and views of some people with a learning disability who had dementia. The dilemmas and obstacles to effective pain management were explored. It was found that the pain experiences and management of people with a learning disability who have dementia mirrored findings in the general population. The research did, however, identify extra and compounding issues in relation to people with a learning disability. Drawing on this research this article outlines recommendations for practitioners and service providers and discusses the key lessons for responding more effectively to pain in people with Downs syndrome and dementia (AU)
Assuntos
Humanos , Masculino , Feminino , Aprendizagem/fisiologia , Deficiências da Aprendizagem/complicações , Deficiências da Aprendizagem/diagnóstico , Demência/complicações , Demência/diagnóstico , Síndrome de Down/complicações , Síndrome de Down/diagnóstico , Dor/complicações , Dor/diagnóstico , Dor/etiologia , Aprendizagem/classificação , Deficiências da Aprendizagem/fisiopatologia , Deficiências da Aprendizagem/terapia , Síndrome de Down/epidemiologia , Síndrome de Down/terapia , Agressão/psicologia , Consciência , Estado de Consciência/fisiologiaRESUMO
AIMS: To monitor microbial community dynamics in a semi-industrial-scale lignocellulosic biofuel reactor system and to improve our understanding of the microbial communities involved in the MixAlco™ biomass conversion process. METHODS AND RESULTS: Reactor microbial communities were characterized at six time points over the course of an 80-day, mesophilic, semi-industrial-scale fermentation using community qPCR and 16S rRNA tag-pyrosequencing. We found the communities to be dynamic, bacterially dominated consortia capable of changing quickly in response to reactor conditions. Clostridia- and Bacteroidetes-like organisms dominated the reactor communities, but ultimately the communities established consortia containing complementary functional capacities for the degradation of lignocellulosic materials. Eighteen operational taxonomic units were found to share strong correlations with reactor acid concentration and may represent taxa integral to fermentor performance. CONCLUSIONS: The results of this study indicate that the emergence of complementary functional classes within the fermentor consortia may be a trait that is consistent across scales, and they suggest that there may be flexibility with respect to the specific identities of the organisms involved in the fermentor's degradation and fermentation processes. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new information regarding the composition, dynamics and potential flexibility of the microbial communities associated with the MixAlco™ process and is likely to inform the improvement of this and other applications that employ mixed microbial communities.
Assuntos
Bactérias/classificação , Biocombustíveis , Reatores Biológicos/microbiologia , Bactérias/genética , Bactérias/isolamento & purificação , Biomassa , Fermentação , Microbiologia Industrial/instrumentação , Reação em Cadeia da PolimeraseRESUMO
The aim of this study was to determine whether the number of animals used in experiments examining reproductive variables could be reduced without loss of statistical efficiency by using monozygotic twin (MT) sheep. In a series of four experiments, we measured the reproductive responses to changes in nutritional, opioidergic, and calcium status and calculated values for twin efficiency (TE) for each variable. In Experiment 1, we monitored the changes in gonadotrophin and testosterone secretion, scrotal circumference and live weight, of MT rams after an acute change in nutritional regime. In Experiment 2, we examined the changes in ovulation rate and gonadotrophin secretion in MT ewes following treatment with bovine follicular fluid. In Experiment 3, we determined responses to naloxone and exogenous calcium on gonadotrophin secretion in MT rams. In Experiment 4, we investigated the effects of naloxone and exogenous calcium on the hypothalamus-pituitary-ovarian axis of MT ewes. The TE values were high only for live weight and scrotal circumference; the other reproductive traits had less variation between than within MT pairs, suggesting that randomly selected animals were just as efficient as genetically identical twins in experiments examining physiological reproductive traits.
Assuntos
Reprodução/fisiologia , Ovinos/fisiologia , Gêmeos Monozigóticos/fisiologia , Animais , Cálcio/farmacologia , Estudos Cross-Over , Feminino , Hormônio Foliculoestimulante/sangue , Líquido Folicular/fisiologia , Hormônio Luteinizante/sangue , Masculino , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Estado Nutricional/fisiologia , Ovulação/fisiologia , Gravidez , Ovinos/sangueRESUMO
The hydrolysis of sucrose, the principal dietary source of carbon for aphids, is catalysed by a gut alpha-glucosidase/transglucosidase activity. An alpha-glucosidase, referred to as APS1, was identified in both a gut-specific cDNA library and a sucrase-enriched membrane preparation from guts of the pea aphid Acyrthosiphon pisum by a combination of genomic and proteomic techniques. APS1 contains a predicted signal peptide, and has a predicted molecular mass of 68 kDa (unprocessed) or 66.4 kDa (mature protein). It has amino acid sequence similarity to alpha-glucosidases (EC 3.2.1.20) of glycoside hydrolase family 13 in other insects. The predicted APS1 protein contains two domains: an N-terminal catalytic domain, and a C-terminal hydrophobic domain. In situ localisation and RT-PCR studies revealed that APS1 mRNA was expressed in the gut distal to the stomach, the same localisation as sucrase activity. When expressed heterologously in Xenopus embryos, APS1 was membrane-bound and had sucrase activity. It is concluded that APS1 is a dominant, and possibly sole, protein mediating sucrase activity in the aphid gut.
Assuntos
Afídeos/enzimologia , Sacarase/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Expressão Gênica , Intestinos/enzimologia , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Pisum sativum/parasitologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , alfa-Glucosidases/metabolismoRESUMO
Synthesis and derivatization of a series of substituted tetrahydrofluorenone analogs giving potent, ERbeta subtype selective ligands are described. Several analogs possessing ERbeta binding affinities comparable to 17beta-estradiol but with greater than 75-fold selectivity over ERalpha are reported.
Assuntos
Receptor beta de Estrogênio/efeitos dos fármacos , Fluorenos/síntese química , Fluorenos/farmacologia , Linhagem Celular , Cristalografia por Raios X , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/química , Fluorenos/classificação , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Root rot pathogens were found through diagnostic surveys in all departments (regions) of Bénin, West Africa, to affect 86 to 100% and 96 to 100% of cassava fields during the dry and rainy seasons, respectively. Disease incidence in individual fields ranged between 0 and 53%, and averaged 16 to 27% per department. Nattrassia mangiferae was consistently the most frequently isolated root rot pathogen (56% in the dry season and 22 to 52% in the rainy season). Pathogenicity of N. mangiferae was confirmed on four cultivars of cassava using stem cuttings and storage roots. For all four cultivars, N. mangiferae significantly reduced the number of roots. Lesions (3 to 15 cm long) formed on the lower stem portion of all inoculated plants, whereas control plants remained symptom free. On storage roots, the disease profile was similar to that formed on stem cuttings. Other root rot pathogens detected during the dry season were Macrophomina phaseolina (14.2%), Fusarium spp. (11.8%), Botryodiplodia theobromae (7.7%), and Pythium spp. (2.9%). During the rainy season, Fusarium spp. were the second most commonly isolated root rot pathogens in three departments (Atlantique, Borgou, and Mono). In Oueme and Zou, B. theobromae was the second most isolated root rot pathogen (ranging between 24 and 28%) during the rainy season. During the same season, Pythium spp. were pronounced in Borgou (18%), followed by Mono (11%), Atlantique (9%), Atacora (8%), Oueme (5%), and Zou (6%). Results of the study are discussed with a view to creating awareness of the destructive power of N. mangiferae, a hitherto poorly recognized root rot pathogen of cassava in Bénin and West Africa in general.
RESUMO
The effects of estrogen receptor (ER) ligands on the stability and transcriptional activity of ERbeta in the breast cancer cell lines MCF-7 and HeLa were examined. We found that ERbeta was degraded in the presence of 17beta-estradiol. Tamoxifen and Faslodex (ICI 182,780) prevented ERbeta receptor destabilization. In contrast to ERalpha, ERbeta degradation was not abolished by inhibitors of the proteasome-mediated protein degradation pathway. Furthermore, single point mutations in helix 12 of the receptor dramatically affected the stability and subsequent transcriptional activation of ERbeta.
Assuntos
Acetilcisteína/análogos & derivados , Neoplasias da Mama/metabolismo , Estradiol/análogos & derivados , Estradiol/metabolismo , Antagonistas de Estrogênios/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Acetilcisteína/metabolismo , Animais , Linhagem Celular Tumoral , Inibidores de Cisteína Proteinase/metabolismo , Estradiol/farmacologia , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/química , Receptor beta de Estrogênio/genética , Feminino , Fulvestranto , Regulação da Expressão Gênica , Genes Reporter , Humanos , Ligantes , Mutação Puntual , Tamoxifeno/metabolismoRESUMO
Sharing a diagnosis of dementia is a key focus of debate and research in the field of dementia care. The pivotal role of the GP in the early identification and subsequent management of dementia has long been recognized and whilst diagnostic practice is improving, the knowledge gained from research exploring the patient perspective is insufficiently absorbed. This paper presents the evidence from the two perspectives of the diagnostic relationship: the views of GPs around giving a diagnosis and the views of patients on receiving one. The authors draw upon their own projects-as well as wider research-in suggesting ways that diagnostic practice can be improved by taking account of the patient perspective. The learning can be distilled around the dimensions of the process, approach and nature of disclosure with evidence particularly challenging the 'myths' held by many GPs around the value of early diagnosis. Whilst much work still needs to be done to incorporate the patient perspective in dementia care, there is clear evidence that patient oriented research has much to offer the development of disclosure practice in primary care to the benefit of patients, their families and GPs.
Assuntos
Demência/diagnóstico , Relações Médico-Paciente , Revelação da Verdade , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Demência/psicologia , Medicina de Família e Comunidade , Humanos , Satisfação do Paciente , Reino UnidoRESUMO
Elderly adults are appropriate targets for objective memory assessment and cognitive testing in the promotion of earlier recognition of people with symptoms of a dementing process. The major change in memory with age is the decline in ability to recall things explicitly. There is a need for education of the general public and health professionals about memory impairment and its relationship with stress, depression, anxiety and dementia.
Assuntos
Transtornos da Memória/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Humanos , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Projetos Piloto , Índice de Gravidade de Doença , Estresse Psicológico/psicologia , Inquéritos e QuestionáriosRESUMO
The breast cancer susceptibility gene product BRCA1 is a tumour suppressor but the biochemical and biological functions that underlie its role in carcinogenesis remain to be determined. Here, we characterise the solution properties of the highly conserved C terminus of BRCA1, consisting of a tandem repeat of the BRCT domain (BRCT-tan), that plays a critical role in BRCA1-mediated tumour suppression. The overall free energy of unfolding of BRCT-tan is high (14.2 kcal mol(-1) at 20 degrees C in water) but unfolding occurs via an aggregation-prone, partly folded intermediate. A representative set of cancer-associated sequence variants was constructed and the effects on protein stability were measured. All of the mutations were highly destabilising and they would be expected to cause loss of function for this reason. Over half could not be purified in a soluble form, indicating that these residues are critical for maintaining structural integrity. The remaining mutants exhibited much greater aggregation propensities than the wild-type, which is most likely a consequence of their reduced thermodynamic stability relative to the partly folded intermediate. The mutations characterised here are located at different sites in the BRCT-tan structure that do not explain fully their effects on the protein's stability. Thus, the results indicate an important role for biophysical studies in assessing the significance of sequence variants and in determining how they cause disease.
Assuntos
Proteína BRCA1/química , Proteína BRCA1/genética , Neoplasias da Mama/química , Neoplasias da Mama/genética , Mutação , Dicroísmo Circular , Clonagem Molecular , Estabilidade de Medicamentos , Feminino , Genes BRCA1 , Variação Genética , Humanos , Técnicas In Vitro , Modelos Moleculares , Desnaturação Proteica , Dobramento de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Soluções , Espectrometria de Fluorescência , Sequências de Repetição em Tandem , TermodinâmicaRESUMO
Racemic beta(2) agonists, composed of equal amounts of (R)- and (S)-isomers, can display anomalous actions that compromise their effectiveness as asthma therapies. Loss of efficacy during regular use is characteristic of isoprenaline, albuterol and terbutaline and has in part been attributed to the biological effects of the (S)-isomer. This hypothesis was applied to the (R,R)- and (S,S)-isomers of formoterol. (R,R)-formoterol had 1000-times greater affinity (2.9 nm) to the human beta(2) adrenoceptor than (S,S)-formoterol (3100 nm), with receptor binding modulating intracellular cAMP levels. The minimum lethal intravenous (IV) dose was determined to be 100 mg/kg for (R,R)- and 50 mg/kg for (S,S)-formoterol, suggesting that the toxicity of (S,S)-formoterol may not be related to the binding of beta(2) adrenoceptors. In tissues pretreated with (S,S)-formoterol but not with (R,R)- or racemic formoterol contractions to high concentrations of carbachol were exaggerated. In vivo experiments with sensitized guinea pigs demonstrated that (R,R)-formoterol inhibited both histamine and antigen-induced bronchoconstriction with greater potency than (R,R/S,S)-formoterol while (S,S)-formoterol was ineffective. Metabolic radiolabeling experiments of (R,R)-, (S,S)- or (R,R/S,S)-formoterol with crude human liver phenolsulfotransferase (PST) determined the V(max)/K(m) values to be (0.151), (0.74) and (0.143), respectively. The reciprocal plot illustrates a 2-fold reduction in sulfation rate when (R,R)-formoterol is present as a single isomer. The data presented here suggest that (R,R)-formoterol binds to the beta(2) adrenoceptor and inhibits the contraction of bronchial tissues by spasmogens. However, (S,S)-formoterol exhibits properties inconsistent as an asthma therapeutic and may antagonize the actions of (R,R)-formoterol.
Assuntos
Agonistas Adrenérgicos beta/toxicidade , Etanolaminas/toxicidade , Músculo Liso/efeitos dos fármacos , Receptores Adrenérgicos beta/metabolismo , Agonistas Adrenérgicos beta/metabolismo , Animais , Relação Dose-Resposta a Droga , Etanolaminas/metabolismo , Feminino , Fumarato de Formoterol , Cobaias , Humanos , Masculino , Contração Muscular/efeitos dos fármacos , Ratos , Receptores Adrenérgicos beta/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade , Traqueia/efeitos dos fármacosRESUMO
A panel of experts attending a 3-day meeting held in Edinburgh, UK, in February 2001 was charged with producing a set of principles outlining the rights and needs of people with intellectual disability (ID)and dementia, and defining service practices which would enhance the supports available to them. The Edinburgh Principles, seven statements identifying a foundation for the design and support of services to people with ID affected by dementia, and their carers, were the outcome of this meeting. The accompanying guidelines and recommendations document provides an elaboration of the key points associated with the Principles and is structured toward a four-point approach: (1) adopting a workable philosophy of care; (2) adapting practices at the point of service delivery; (3) working out the coordination of diverse systems; and (4) promoting relevant research. It is expected that the Principles will be adopted by service organizations world-wide, and that the accompanying document will provide a useful and detailed baseline from which further discussions, research efforts and practice development can progress.
Assuntos
Doença de Alzheimer/reabilitação , Demência/reabilitação , Necessidades e Demandas de Serviços de Saúde , Deficiência Intelectual/reabilitação , Defesa do Paciente , Atenção à Saúde , Humanos , Equipe de Assistência ao Paciente , Qualidade de Vida , Pesquisa , Apoio Social , Reino Unido , Estados UnidosRESUMO
Elderly adults are appropriate targets for objective memory assessment and cognitive testing in the promotion of earlier recognition of people with symptoms of a dementing process. The major change in memory with age is the decline in ability to recall things explicitly. There is a need for education of the general public and health professionals about memory impairment and its relationship with stress, depression, anxiety and dementia.
RESUMO
Elderly adults are appropriate targets for objective memory assessment and cognitive testing in the promotion of earlier recognition of people with symptoms of a dementing process. The major change in memory with age is the decline in ability to recall things explicitly. There is a need for education of the general public and health professionals about memory impairment and its relationship with stress, depression, anxiety and dementia.
RESUMO
p13suc1 (suc1) has two native states, a monomer and a domain-swapped dimer. The structure of each subunit in the dimer is identical to that of the monomer, except for the hinge loop that connects the exchanging domains. Here we find that single point mutations at sites throughout the protein and ligand binding both shift the position of the equilibrium between monomer and dimer. The hinge loop was shown previously to act as a loaded molecular spring that releases tension present in the monomer by adopting an alternative conformation in the dimer. The results here indicate that the release of strain propagates throughout the entire protein and alters the energetics of regions remote from the hinge. Our data illustrate how the signal conferred by the conformational change of a protein loop, elicited by domain swapping, ligand binding or mutation, can be sensed by a distant active site. This work highlights the potential role of strained loops in proteins: the energy they store can be used for both signal transduction and allostery, and they could steer the evolution of protein function. Finally, a structural mechanism for the role of suc1 as an adapter molecule is proposed.