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Tau prions feature in the brains of patients suffering from Alzheimer's disease and other tauopathies. For the development of therapeutics that target the replication of tau prions, a high-content, fluorescence-based cell assay was developed. Using this high-content phenotypic screen for nascent tau prion formation, a 4-piperazine isoquinoline compound (1) was identified as a hit with an EC50 value of 390 nM and 0.04 K p,uu. Analogs were synthesized using a hypothesis-based approach to improve potency and in vivo brain penetration resulting in compound 25 (EC50 = 15 nM; K p,uu = 0.63). We investigated the mechanism of action of this series and found that a small set of active compounds were also CDK8 inhibitors.
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Dravet syndrome is a life-threatening early-onset epilepsy not well controlled by antiepileptic drugs. Drugs that modulate serotonin (5-HT) signalling, including clemizole, locaserin, trazodone and fenfluramine, have recently emerged as potential treatment options for Dravet syndrome. To investigate the serotonin receptors that could moderate this antiepileptic activity, we designed and synthesized 28 novel analogues of clemizole, obtained receptor binding affinity profiles, and performed in vivo screening in a scn1lab mutant zebrafish (Danio rerio) model which recapitulates critical clinical features of Dravet syndrome. We discovered three clemizole analogues with 5-HT receptor binding that exert powerful antiepileptic activity. Based on structure-activity relationships and medicinal chemistry-based analysis, we then screened an additional set of known 5-HT receptor specific drug candidates. Integrating our in vitro and in vivo data implicates 5-HT2B receptors as a critical mediator in the mechanism of seizure suppression observed in Dravet syndrome patients treated with 5-HT modulating drugs.
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In this work we present a direct catalytic synthesis of γ-lactams and pyrrolidines from alkenes and activated unsaturated amides or protected unsaturated amines, respectively. Using a mesityl acridinium single electron photooxidant and a thiophenol cocatalyst under irradiation, we are able to directly forge these important classes of heterocycles with complete regiocontrol.
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Amidas/química , Aminas/química , Lactamas/síntese química , Fenóis/química , Pirrolidinas/síntese química , Compostos de Sulfidrila/química , Catálise , Reação de Cicloadição , Lactamas/química , Estrutura Molecular , Oxirredução , Processos Fotoquímicos , Pirrolidinas/químicaRESUMO
The direct anti-Markovnikov addition of strong Brønsted acids to alkenes remains an unsolved problem in synthetic chemistry. Here, we report an efficient organic photoredox catalyst system for the addition of HCl, HF and also phosphoric and sulfonic acids to alkenes, with complete regioselectivity. These transformations were developed using a photoredox catalyst in conjunction with a redox-active hydrogen atom donor. The nucleophile counterion plays a critical role by ensuring high reactivity, with 2,6-lutidinium salts typically furnishing the best results. The nature of the redox-active hydrogen atom donor is also consequential, with 4-methoxythiophenol providing the best reactivity when 2,6-lutidinium salts are used. A novel acridinium sensitizer provides enhanced reactivity within several of the more challenging reaction manifolds. This Article demonstrates how nucleophilic addition reactions mediated by photoredox catalysis can change the way electrophilic and homofugal precursors are constructed.
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Alcenos/química , Estirenos/química , Ácidos Sulfônicos/química , Catálise , Halogenação , Hidrogênio/química , Oxirredução , Piridinas/químicaRESUMO
The surface modification of lamellar silica prepared by liquid crystal templating has been investigated. Two hydrophilic surface modifier agents, 2-glycidoxypropyltrimethoxysilane and 2-[methoxy(polyethyleneoxy)propyl)]trimethoxysilane, have been tested. Characterizations of the modified silica include thermal analysis, (13)C and (29)Si solid state NMR, transmission electron microscopy (TEM) and X-ray diffraction (XRD). The different characterizations confirmed the preservation of the lamellar morphology and the successful surface modification with both silanes along with the template elimination. The results also indicate that the structure and length of the silanes influence the final lamellar organization as well as the grafting yields and mechanisms.
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OBJECTIVE: To investigate the prevalence of anal incontinence in the general population and in patients consulting gastroenterologist and gynecologist practices in the Rhône Alpes area. METHODS: For the first study a questionnaire was sent to a sample of 2800 people selected randomly from the electoral roll. Another study of patients selected randomly among patients attending gynecology and gastroenterology consultations was performed. A Jorge & Wexner score above or equal to 5 was used to define anal incontinence. RESULTS: For the first study, a total of 706 questionnaires was analyzed: the prevalence of anal incontinence was 5.1% [95% CI: 3.6-7.0] and the scores of each dimension of the SF-12 Health Survey were significantly lower among incontinent people than among continent people. The prevalence was significantly higher for women (7.5% [5.0-10.7]) than for men (2.4% [1.1-4.7]). Eighty-four physicians returned 835 valid questionnaires. The prevalence was 13.1% [10.1-16.6] among patients attending gastroenterology consultations and 5.0% [3.1-7.6] among those attending gynecology consultations. For 84.8% of the incontinent patients, the physician was unaware of the patient's disorder. CONCLUSION: The prevalence figures we obtained coincide with data in the literature. This disorder is common and affects the patient's quality-of-life, but remains underestimated and under-diagnosed.
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Incontinência Fecal/complicações , Incontinência Fecal/epidemiologia , Qualidade de Vida , Adulto , Idoso , Incontinência Fecal/psicologia , Feminino , França/epidemiologia , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , PrevalênciaRESUMO
Recently, to answer patients, caregivers and professionals needs, the "Plan Cancer" has been presented by the French Government. This plan is intended to improve quality of care in cancer patients and finally, patients' survival and quality of life. This planned strategy stresses the importance of organized interactions between hospitals and between the various health professionals. Measuring the number of patients with cancer and the activity related to cancer in large networks of multidisciplinary hospitals has became a real challenge in France for organizational, quality of care and economic reasons. Many University Hospitals in France have chosen to face this question by using the French DRG based information system called PMSI. It allows estimating the proportion of hospital stays concerned by cancers that are identified with algorithms based on ICD 10. However, French databases of hospital discharges do not allow patients identification. We collected data on hospital stays and patients in a subset of an organized network focused on cancer care and composed of 55 public or private hospitals in the Rhone-Alpes area. We used these data to estimate the number of patients who had been hospitalized within the network in 2000. Approximately 110,000 hospital stays were related with a diagnostic of cancer, corresponding to a number of patients within a range of 30345 to 35700. In absence of communicating files between hospitals, claims databases are an interesting source of information for cancer burden. The recent implementation of a procedure allowing the linkage of data concerning each patient should permit better estimates in the future. The main limitation will remain the possibility of a hospital to participate to more than one network.
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Grupos Diagnósticos Relacionados/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Neoplasias/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Bases de Dados Factuais/estatística & dados numéricos , Feminino , França/epidemiologia , Hospitais Privados/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Neoplasias/terapia , Distribuição por SexoRESUMO
BACKGROUND: The aim of this study was to assess the myocardial reflectivity pattern in severe aortic valve stenosis through the use of integrated backscatter (IBS) analysis. Patients with aortic stenosis (AS) were carefully selected in the Department of Cardiology. METHODS AND RESULTS: Thirty-five subjects (AS: valve orifice < or =1 cm2; 12 female; mean age, 71.8+/-6.2 years) and 25 healthy subjects were studied. All subjects of the study had conventional 2D-Doppler echocardiography and IBS. Backscatter signal was sampled at the septum and posterior wall levels. Patients with AS were divided into 2 groups: 16 patients with initial signs of congestive heart failure and a depressed left ventricular systolic function (DSF) (ejection fraction [EF] range, 35% to 50%) and 19 asymptomatic patients with normal left ventricular systolic function (NSF) (EF >50%). Myocardial echo intensity (pericardium related) was significantly higher at the septum and posterior wall levels in DSF than in NSF and in control subjects. IBS variation, as an expression of variation of the signal, appeared to be significantly lower in AS with DSF than in NSF and in control subjects, at both the septum and posterior wall levels. Patients with DSF underwent aortic valve replacement, and, during surgical intervention, a septal myocardial biopsy was made for evaluation of myocardium/fibrosis ratio. Abnormally increased echo intensity was detected in left ventricular pressure overload by severe aortic stenosis and correlated with increase of myocardial collagen content (operating biopsy). CONCLUSIONS: One year after aortic valve replacement, we observed a significant reduction of left ventricular mass, and, only if pericardial indexed IBS value (reduction of interstitial fibrosis) decreased, it was possible to observe an improvement of EF and of IBS variation.
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Estenose da Valva Aórtica/diagnóstico por imagem , Colágeno/análise , Ecocardiografia/métodos , Miocárdio/patologia , Idoso , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Biópsia , Densitometria , Ecocardiografia Doppler , Feminino , Fibrose , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Septos Cardíacos/química , Septos Cardíacos/patologia , Implante de Prótese de Valva Cardíaca , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Pressão , Prognóstico , Volume Sistólico , Sístole , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
PURPOSE: The potential advantage of high-dose preoperative radiotherapy to increase tumor response and improve the chance of sphincter preservation for low rectal cancer remains controversial. The aim of this trial was to evaluate the role of escalating the dose of preoperative radiation to increase sphincter-saving procedures. PATIENTS AND METHODS: Patients with rectal carcinoma located in the lower rectum, staged T2 or T3, Nx, or M0 with endorectal sonography, and not involving more than two-thirds circumference, were randomly assigned to one of two groups: preoperative external-beam radiotherapy (EBRT; 39 Gy in 13 fractions over 17 days) versus the same EBRT with boost (85 Gy in three fractions) using endocavitary contact x-ray. RESULTS: Between 1996 and 2001, 88 patients were enrolled onto the study. A significant improvement was seen in favor of the contact x-ray boost for complete clinical response (24% v 2%) and for a complete or near-complete sterilization of the operative specimen (57% v 34%). A significant increase in sphincter preservation was observed in the boost group (76% v 44%; P =.004). At a median follow-up of 35 months, there was no difference in morbidity, local relapse, and 2-year overall survival. CONCLUSION: A dose escalation with endocavitary irradiation provides increased tumor response and sphincter preservation with no detrimental effect on treatment toxicity and early clinical outcome.
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Canal Anal/efeitos da radiação , Neoplasias Retais/radioterapia , Adulto , Idoso , Canal Anal/cirurgia , Terapia Combinada , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/epidemiologia , Dosagem Radioterapêutica , Neoplasias Retais/mortalidade , Neoplasias Retais/cirurgia , Taxa de SobrevidaRESUMO
The interaction of polyvinylpyrrolidone (PVP) with an anionic surfactant (sodium dodecyl sulfate, SDS), a nonionic surfactant (pentaethylene glycol monodecyl ether, C(10)E(5)), and a zwitterionic surfactant (lauryl amido propyl betaine, LAPB) has been investigated by means of pulsed gradient spin-echo NMR (FT-PGSE NMR), allowing self-diffusion coefficients to be determined. The results confirm the strong interaction prevailing in the PVP/SDS system, whereas no association has been observed in the PVP/C(10)E(5) and PVP/LAPB systems. Mixing PVP with two surfactants, namely SDS and C(10)E(5) or SDS and LAPB, results in the formation of ternary aggregates between the polymer and the mixed micelles. Copyright 2001 Academic Press.
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Carnitine is involved in the transfer of fatty acids across mitochondrial membranes. Carnitine is found in dairy and meat products, but is also biosynthesized from lysine and methionine via a process that, in rat, takes place essentially in the liver. After intestinal absorption or hepatic biosynthesis, carnitine is transferred to organs whose metabolism is dependent on fatty acid oxidation, such as heart and skeletal muscle. In skeletal muscle, carnitine concentration was found to be 50 times higher than in the plasma, implicating an active transport system for carnitine. In this study, we characterized this transport in isolated rat myotubes, established mouse C2C12 myoblastic cells, and rat myotube plasma membranes and found that it was Na(+)-dependent and partly inhibited by a Na(+)/K(+) ATPase inhibitor. L-carnitine analogues such as D-carnitine and gamma-butyrobetaine interfere with this system as does acyl carnitine. Among these inhibitors, the most potent was mildronate (3-(2,2,2-trimethylhydrazinium)propionate), known as a gamma-butyrobetaine hydroxylase inhibitor. It also induced a marked decrease in carnitine transport into muscle cells. Removal of carnitine or treatment with mildronate induced growth inhibition of cultured C2C12 myoblastic cells. These data suggest that myoblast growth and/or differentiation is dependent upon the presence of carnitine.
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Carnitina/metabolismo , Metilidrazinas/farmacologia , Músculo Esquelético/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Técnicas In Vitro , Masculino , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Carnitine biosynthesis from lysine and methionine involves five enzymatic reactions. gamma-butyrobetaine hydroxylase (BBH; EC 1.14. 11.1) is the last enzyme of this pathway. It catalyzes the reaction of hydroxylation of gamma-butyrobetaine to carnitine. The cDNA encoding this enzyme has been isolated and characterized. The cDNA contained an open reading frame of 1161 bp encoding a protein of 387 amino acids with a deduced molecular weight of 44.5 kDa. The sequence of the cDNA showed an important homology with the human cDNA recently isolated. Northern analysis showed gamma-butyrobetaine hydroxylase expression in the liver and in some extend in the testis and the epididymis. During this study, it also appeared that BBH mRNA expression was undetectable by Northern analysis during the perinatal period. During the development of the rat, the amount of BBH mRNA appeared after the weaning of the young rat and reached a maximal expression at the adult stage.
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Fígado/enzimologia , Oxigenases de Função Mista/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , DNA Complementar/isolamento & purificação , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Oxigenases de Função Mista/química , Dados de Sequência Molecular , Ratos , Ratos Wistar , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , gama-Butirobetaína DioxigenaseRESUMO
Within the limits granted, neuroleptanalgesia constitutes a very interesting technique in the major part of management of labour. In particular it has the advantage of preserving maternal consciousness. On the other hand, it allows analgesia of rather long duration, which renders early management of labour possible while still respecting its physiology. The institution of this technique demands the presence at the parturients bedside, not only of the obstetrician and the medwife but also that of a qualified anesthetist. As in all cases of major management of labour it engages the responsability of the obstetrical team which undertakes it and this is even more so, the earlier it is started. To us its indications seem comparable with those of Gamma OH: the early management of labour however has the advantage over the latter of preserving maternal consciouness. Moreover it proved to be particularly interesting in the management of breech presentations. But if its properties are an advantage in the indications which we have just mentioned, they can constitute an invonvenience and restrain its use under different circumstances: its slowness of induction, the absence of narcosis which limits the effect on cervical resistance means that one prefers the Toulouse method using pentothal for the management of labour after 7 centimeters of dilatation. In conclusion, it seems important to us to state that neuroleptanalgesia is not the ideal method for management of labour any more than is thiopental or Gamma-OH. Other techniques merit being studied. Their study must obey strict rules in order to specify the risks and therefore the indications and limits. It should cover different fields which are, pharmacology, the objective assessment, by quantitative criteria, of the effects on uterine contraction, on the mother's clinical and biological state as well as that of the fetus in utero, then that of the child in the first hours of live and up to the first years of his development.