RESUMEN
The observation of ready deprotonation of the phenylogous enol of benzodifurantrione (BDT) to give a bright violet conjugate base has led to two follow up explorations. Extension of BDT enol by insertion of a p-phenylene unit into the enol C-O bond gives the known bright red 4-hydroxylated benzodifuranone dyes. Their deprotonation results in previously unreported near infrared-absorbing conjugate bases. These appear to aggregate in solution, the more so in less polar solvents. Ring-opened derivatives of BDT containing α-dicarbonyl substituents also give coloured conjugate bases, but α-keto-ester and -anilide derivatives differ substantially (ester yellow; anilide intense red). Investigation of this nonintuitive difference leads to the conclusion that while the anilide is essentially planar the ester is nonplanar. The contrast in conformation impacts on the auxochromic effects of the otherwise closely related α-dicarbonyl substituents and thus the variation in colour. The latter observation has potential across colour chemistry in general. In contrast to the readily observed BDT enol, no evidence has been adduced for enol tautomers amongst the ring-opened analogues.
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Colorantes , Ésteres , Conformación Molecular , Solventes/químicaRESUMEN
BACKGROUND: Melatonin is a potent oxygen scavenger and is capable of altering blood flow in various vascular beds. AIMS: We aimed to determine the effect of melatonin on ovarian vascular indices during ovarian stimulation for in vitro fertilisation (IVF). MATERIALS AND METHODS: This is a pilot double-blind placebo-controlled randomised trial. Sixty-nine women (mean age 35.8 ± 4.3 years) undergoing their first cycle of IVF were randomised to receive either placebo, 2, 4 or 8 mg of melatonin, twice a day. Each participant underwent a transvaginal ultrasound at days 6-10 assessing follicular number and size. The vascularisation index (VI), flow index (FI) and vascularisation-flow index (VFI) were measured. These indices were then correlated with embryological outcomes. Informed consent was obtained from participants. This trial was registered with the Australia New Zealand Clinical Trials Registry (ACTRN12613001317785). RESULTS: The number of follicles did not differ between groups (P = 0.4). There were no differences in the VI (P = 0.4), FI (P = 0.1) or VFI (P = 0.3) in the right ovary or the FI (P = 0.3) or VFI (P = 0.3) in the left ovary between groups. When comparing placebo to any dose of melatonin, there were no differences in any measured parameter. While there was correlation between the number of follicles on ultrasound and all measured embryological outcomes, there was no correlation between ovarian vascular indices and these important clinical outcomes. CONCLUSIONS: Melatonin does not appear to change ovarian vascular indices during ovarian stimulation. In addition, such vascular indices cannot predict the number or quality of oocytes or embryos obtained in an IVF cycle. These findings require confirmation in future larger studies.
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Fertilización In Vitro/efectos de los fármacos , Melatonina/administración & dosificación , Folículo Ovárico/efectos de los fármacos , Adulto , Biomarcadores , Método Doble Ciego , Femenino , Humanos , Oocitos/efectos de los fármacos , Folículo Ovárico/diagnóstico por imagen , Inducción de la Ovulación , Proyectos Piloto , Ultrasonografía , Ultrasonografía DopplerRESUMEN
Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases.
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Diferenciación Celular , Medios de Cultivo/farmacología , Hepatocitos/citología , Ligamento Periodontal/citología , Células Madre/citología , Biomarcadores/análisis , Diferenciación Celular/efectos de los fármacos , Medios de Cultivo/química , Regulación del Desarrollo de la Expresión Génica , Humanos , Células Madre/efectos de los fármacosRESUMEN
An efficient and low cost optical method for directly measuring the concentration of homogenous biological solutes is proposed and demonstrated. The proposed system operates by Fresnel reflection, with a flat-cleaved single-mode fiber serving as the sensor probe. A laser provides a 12.9 dBm sensor signal at 1,550 nm, while a computer-controlled optical power meter measures the power of the signal returned by the probe. Three different mesenchymal stem cell (MSC) lines were obtained, sub-cultured and trypsinized daily over 9 days. Counts were measured using a haemocytometer and the conditioned media (CM) was collected daily and stored at -80 °C. MSCs release excretory biomolecules proportional to their growth rate into the CM, which changes the refractive index of the latter. The sensor is capable of detecting changes in the number of stem cells via correlation to the change in the refractive index of the CM, with the measured power loss decreasing approximately 0.4 dB in the CM sample per average 1,000 cells in the MSC subculture. The proposed system is highly cost-effective, simple to deploy, operate, and maintain, is non-destructive, and allows reliable real-time measurement of various stem cell proliferation parameters.
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Biopolímeros/análisis , Biopolímeros/biosíntesis , Medios de Cultivo/análisis , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Fotometría/instrumentación , Refractometría/instrumentación , Técnicas Biosensibles/instrumentación , Proliferación Celular , Células Cultivadas , Medios de Cultivo/química , Diseño de Equipo , Análisis de Falla de Equipo , Citometría de Flujo/instrumentación , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The first example of a stable phenylogous enol, resulting from an extended keto-enol tautomerization across a benzene ring, is described. The enol has been isolated, and its structure was proven by X-ray crystallography. The equilibrium between the keto- and enol-tautomers has been extensively studied and quantified in solution by NMR and UV-vis spectroscopy. The position of equilibrium showed a linear correlation to the Kamlet-Taft solvatochromic scale for solvent H-bond acceptor strength (beta(OmicronEta)), and the equilibrium was proven to be fully dynamic, obeying first-order equilibrium kinetics. To attempt to explain why enolization occurs, at what surprisingly appears to be the expense of aromatic resonance stabilization, various structural features have been considered and explored further with the aid of MO calculations. Nucleus independent chemical shift (NICS) index of aromaticity calculations for each of the rings comprising both tautomers showed that while the central benzene ring loses aromaticity on enolization, the alpha-keto-lactone ring showed an unexpected and significant antiaromaticity in the keto-tautomer, which is by no means intuitive. The loss of stabilization energy associated with the central benzene ring is, therefore, to a certain degree compensated by removal of the antiaromatic destabilization of the alpha-keto-lactone ring rendering the two structures much closer in energy than would otherwise be expected.
RESUMEN
A retrospective review of medical records was performed to assess the incidence and types of significant complications encountered during laparoscopic hysterectomy which would affect the use of a laparoscopic approach versus other routes of hysterectomy. A total of 526 consecutive patients' medical data between January 1994 and August 2007 were reviewed. Two hundred and thirty-two laparoscopic-assisted vaginal hysterectomies and 294 total laparoscopic hysterectomies were performed at Monash Medical Centre, a Melbourne tertiary public hospital, and three Melbourne private hospitals, by or under the supervision of three surgeons. Sixteen significant complications occurred. There were two cases of ureteric fistula, two bladder injuries, two bowel obstructions, four postoperative haematomas, one case of a bladder fistula, four conversions to laparotomy and one superficial epigastric artery injury. Inpatient stay ranged from two to six days. Our complication and inpatient stay rates are consistent with the previously reported rates, although there has been a reduction of incidence of visceral injuries with experience and introduction of new equipment.
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Histerectomía/efectos adversos , Laparoscopía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Adulto , Femenino , Estudios de Seguimiento , Hospitales Públicos/estadística & datos numéricos , Humanos , Histerectomía/métodos , Incidencia , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Victoria/epidemiologíaRESUMEN
We describe herein the discovery and development of a series of 4-arylthieno[3,2-d]pyrimidines which are potent adenosine A(2A) receptor antagonists. These novel compounds show high degrees of selectivity against the human A(1), A(2B) and A(3) receptor sub-types. Moreover, a number of these compounds show promising activity in vivo, suggesting potential utility in the treatment of Parkinson's disease.
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Antagonistas del Receptor de Adenosina A2 , Antiparkinsonianos/uso terapéutico , Diseño de Fármacos , Trastornos Parkinsonianos/tratamiento farmacológico , Pirimidinas/uso terapéutico , Antagonistas del Receptor de Adenosina A1 , Antagonistas del Receptor de Adenosina A3 , Antiparkinsonianos/síntesis química , Humanos , Modelos Químicos , Pirimidinas/síntesis química , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
The (-)-(11R,2'S)-enantiomer of the antimalarial drug mefloquine has been found to be a reasonably potent and moderately selective adenosine A(2A) receptor antagonist. Further investigation of this compound has led to the discovery of a series of keto-aryl thieno[3,2-d]pyrimidine derivatives, which are potent and selective antagonists of the adenosine A(2A) receptor. These derivatives show selectivity against the A(1) receptor. Furthermore, some of these compounds have been shown to have in vivo activity in a commonly used model, suggesting the potential for the treatment of Parkinson's disease.
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Antagonistas del Receptor de Adenosina A2 , Antimaláricos/uso terapéutico , Antiparkinsonianos/uso terapéutico , Trastornos Parkinsonianos/tratamiento farmacológico , Pirimidinas/uso terapéutico , Antimaláricos/síntesis química , Antiparkinsonianos/síntesis química , Humanos , Modelos Químicos , Pirimidinas/síntesis química , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
Purpose: To explore in a small pilot study whether oral melatonin, administered during ovarian stimulation increases clinical pregnancy rate (CPR) after IVF and what dose might be most effective. Methods: Pilot double-blind, dose-finding, placebo-controlled randomized clinical trial in private IVF clinics in Australia between September 2014 and September 2016. One hundred and sixty women having their first cycle of IVF or ICSI were randomized to receive placebo (n = 40), melatonin 2 mg (n = 41), melatonin 4 mg (n = 39), or melatonin 8 mg (n = 40) twice per day (BD) during ovarian stimulation. The primary outcome was CPR. Secondary outcomes included serum and follicular fluid (FF) melatonin concentrations, oocyte/embryo quantity/quality, and live birth rate (LBR). Analysis was performed using the intention-to-treat principle. Results: There was no difference in CPR or LBR between any of the four groups (p = 0.5). When all the doses of melatonin were compared as a group with placebo, the CPR was 21.7% for the former and 15.0% for the latter [OR 1.57 (95% CI 0.59, 4.14), p = 0.4]. There were also no differences between the groups in total oocyte number, number of MII oocytes, number of fertilized oocytes, or the number or quality of embryos between the groups. This is despite mean FF melatonin concentration in the highest dose group (8 mg BD) being nine-fold higher compared with placebo (P < 0.001). Conclusion: No significant differences were observed in CPR or oocyte and embryo parameters despite finding a nine-fold increase in FF melatonin concentration. However, this study was not sufficiently powered to assess differences in CPR and therefore, these results should be interpreted with caution. Because this was a small RCT, a beneficial effect of melatonin on IVF pregnancy rates cannot be excluded and merits confirmation in further, larger clinical trials. ANZCTR (http://www.anzctr.org.au/ Project ID: ACTRN12613001317785).
RESUMEN
STUDY QUESTION: Does melatonin result in a dose-response effect on sleep quality and daytime sleepiness in women undergoing IVF? SUMMARY ANSWER: Melatonin, even when given at high doses twice per day, does not cause significant daytime sleepiness or change night time sleep quantity or quality. WHAT IS KNOWN ALREADY: Melatonin is being increasingly used as an adjuvant therapy for women undergoing IVF owing to its antioxidative effects. It is widely considered to be sedative but there are scant objective data on the effects of melatonin on sleep in the setting of IVF. STUDY DESIGN SIZE DURATION: The study was a double-blind placebo-controlled randomized trial of 116 women recruited between September 2014 and September 2016. PARTICIPANTS/MATERIALS SETTING METHOD: Women who were undergoing their first cycle of IVF at private IVF centers were recruited into the RCT and randomized to receive either placebo, 2 mg, 4 mg or 8 mg of melatonin, twice per day (BD) from Day 2 of their cycle until the day before oocyte retrieval. Each participant wore an accelerometer that provides an estimate of sleep and wake activity for up to 1 week of baseline and throughout treatment (up to 2 weeks). They also kept sleep diaries and completed a Karolinska sleepiness score detailing their night time sleep activity and daytime sleepiness, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 116 women were included in the intention-to-treat analysis (placebo BD (n = 32), melatonin 2 mg BD (n = 29), melatonin 4 mg BD (n = 26), melatonin 8 mg BD (n = 29)). There were no significant differences in daytime Karolinska sleepiness score between groups (P = 0.4), nor was there a significant dose-response trend (ß=0.05, 95% CI -0.22-0.31, P = 0.7). There were no differences in objective measures of sleep quantity or quality, including wake after sleep onset time, sleep onset latency, and sleep efficiency before and after treatment or between groups. There was an improvement in subjective sleep quality scores from baseline to during treatment in all groups, except 8 mg BD melatonin: placebo (percentage change -13.3%, P = 0.01), 2 mg (-14.1%, P = 0.03), 4 mg (-8.6%, P = 0.01) and 8 mg (-7.8%, P = 0.07). LIMITATIONS REASONS FOR CAUTION: As this was a subset of a larger trial, the melatonin in ART (MIART) trial, it is possible that the sample size was too small to detect statistically significant differences between the groups. WIDER IMPLICATIONS OF THE FINDINGS: While this study suggests that melatonin can be used twice per day at high doses to achieve sustained antioxidation effects, with the reassurance that this will not negatively impact daytime sleepiness or night time sleep habits, the sample size is small and may have missed a clinically significant difference. Nevertheless, our findings may have implications not only for future studies of fertility treatments (including meta-analyses), but also in other medical fields where sustained antioxidation is desired. STUDY FUNDING/COMPETING INTERESTS: This study was funded by the Monash IVF Research and Education Foundation (PY12_15). S.F. is supported by the National Health and Medical Research Council (Postgraduate Scholarship APP1074342) and the Royal Australian and New Zealand College of Obstetricians and Gynaecologists Ella Macknight Memorial Scholarship. E.W. is supported by an National Health and Medical Research Council Program Grant (APP1113902). S.F., E.W., R.H., B.V., N.L., N.H., M.W., M.L., A.L., P.T., K.L. have nothing to declare. L.R. is a Minority shareholder in Monash IVF Group, has unrestricted grants from MSD®, Merck-Serono® and Ferring® and receives consulting fees from Ferring®. S.N.B. reports consulting fees from Johnson & Johnson Consumer Inc®, outside the submitted work. TRIAL REGISTRATION NUMBER: This trial was prospectively registered with the Australian New Zealand Clinical Trials Registry (Project ID: ACTRN12613001317785). TRIAL REGISTRATION DATE: 27/11/2013. DATE OF FIRST PATIENT'S ENROLMENT: 1/9/2014.
RESUMEN
This prospective observational study aimed to assess the feasibility of adapting peritoneal hyperdistention to 25 mmHg during laparoscopy in an Australian hospital environment. A total of 1150 consecutive diagnostic or operative laparoscopies were performed. All cases were monitored for early detection of untoward physiological changes. All patients had Veress needle insufflation with distension to 25 mmHg prior to insertion of the primary trocar. No patients experienced any surgical entry complications or adverse clinical effects noted during anaesthetic. The aim of the current study is to assess the feasibility and safety of increasing the peritoneal insufflation pressure to 25 mmHg for primary trocar insertion.
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Laparoscopía/métodos , Instrumentos Quirúrgicos , Abdomen/fisiopatología , Abdomen/cirugía , Australia , Humanos , Cuidados Intraoperatorios , Complicaciones Intraoperatorias , Laparoscopía/efectos adversos , Monitoreo Fisiológico , Presión , Estudios Prospectivos , Reproducibilidad de los ResultadosRESUMEN
The 5'-triphosphates of 2'-hydroxymethyluridine (2'-homouridine) and 2'-hydroxyethyluridine were prepared from the corresponding acetyl-protected nucleosides by initial phosphitylation with 2-chloro-5,6-benzo-1,2,3-dioxaphosphorin-4-one. 2'-Acetamidouridine 5'-triphosphate was prepared in an analogous fashion from uridine 2'-C-, 3'-O-gamma-butyrolactone, in which the 3'-hydroxyl group is internally protected as the lactone. Subsequent treatment with ammonia gave the required acetamido triphosphate. All three triphosphates were investigated as substrates for T7 RNA polymerase and a Y639F mutant of this enzyme. 2'-Homouridine triphosphate was found to be a substrate for the wild-type enzyme in the presence of manganese and was specifically incorporated into short RNA transcripts (20 and 21 nucleotides in length). The presence of the analogue within the transcripts was confirmed through its resistance to alkaline hydrolysis. Gel electrophoretic analysis also showed that 2'-homouridine could be multiply incorporated into a transcript with a length of 75 nucleotides. This is the first report of a 2'-deoxy-2'-alpha-C-branched nucleoside 5'-triphosphate acting as a substrate for T7 RNA polymerase. The 2'-hydroxyethyl- and 2'-acetamido -uridine triphosphates were not substrates for the enzymes.
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ARN Polimerasas Dirigidas por ADN/metabolismo , Transcripción Genética , Uridina Trifosfato/síntesis química , Uridina/química , Proteínas Virales/metabolismo , ARN Polimerasas Dirigidas por ADN/genética , Electroforesis en Gel de Poliacrilamida , Mutación , Uridina Trifosfato/análogos & derivados , Uridina Trifosfato/genética , Proteínas Virales/genéticaRESUMEN
OBJECTIVE: The purpose of this study was to assess the level of skill of laparoscopic surgeons in electrosurgery. DESIGN: Subjects were asked to complete a practical diathermy station and a written test of electrosurgical knowledge. SETTING: Tests were held in teaching and non-teaching hospitals. SAMPLE: Twenty specialists in obstetrics and gynaecology were randomly selected and tested on the Monash University gynaecological laparoscopic pelvi-trainer. Twelve candidates were consultants with 9-28 years of practice in operative laparoscopy, and 8 were registrars with up to six years of practice in operative laparoscopy. Seven consultants and one registrar were from rural Australia, and three consultants were from New Zealand. METHODS: Candidates were marked with checklist criteria resulting in a pass/fail score, as well as a weighted scoring system. We retested 11 candidates one year later with the same stations. MAIN OUTCOME MEASURES: No improvement in electrosurgery skill in one year of obstetric and gynaecological practice. RESULTS: No candidate successfully completed the written electrosurgery station in the initial test. A slight improvement in the pass rate to 18% was observed in the second test. The pass rate of the diathermy station dropped from 50% to 36% in the second test. CONCLUSION: The study found ignorance of electrosurgery/diathermy among gynaecological surgeons. One year later, skills were no better.
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Competencia Clínica/normas , Diatermia/normas , Electrocirugia/normas , Ginecología/normas , Obstetricia/normas , Escolaridad , Femenino , Humanos , Nueva Zelanda , Estudios ProspectivosRESUMEN
Continuous recording of the activity of recombinant adenylate cyclase (CyaA) of Bordetella pertussis (EC ) by conductimetric determination of enzyme-coupled pyrophosphate cleavage has enabled us to define a number of novel features of the activation of this enzyme by calmodulin and establish conditions under which valid activation data can be obtained. Activation either in the presence or absence of calcium is characterized by a concentration-dependent lag phase. The rate of formation and breakdown of the activated complex can be determined from an analysis of the lag phase kinetics and is in good agreement with thermodynamic data obtained by measuring the dependence of activation on calmodulin concentration, which show that calcium increases k(on) by about 30-fold. The rate of breakdown of the activated complex, formed either in the presence or absence of calcium, has been determined by dilution experiments and has been shown to be independent of the presence of calcium. The coupled assay is established as a rapid, convenient and safe method which should be readily applicable to the continuous assays of most other enzymes that catalyze reactions in which inorganic pyrophosphate is liberated.
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Adenilil Ciclasas/química , Bioquímica/métodos , Bordetella pertussis/enzimología , Calmodulina/metabolismo , Pirofosfatasas/metabolismo , Toxina de Adenilato Ciclasa , Adenilil Ciclasas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Calibración , Catálisis , Relación Dosis-Respuesta a Droga , Electrofisiología , Escherichia coli/metabolismo , Cinética , Unión Proteica , Precursores de Proteínas/química , Precursores de Proteínas/metabolismo , Estructura Terciaria de Proteína , Proteínas Recombinantes/metabolismo , Temperatura , Factores de TiempoRESUMEN
En este artículo analizamos la evidencia experimental del fenómeno llamado de percepción extrasensorial. Nos centramos en los trabajos experimentales realizados en centros académicos y universitarios y, en particular, en estudios que se han basado en un método de monotonización perceptiva y aislamiento sensorial parcial, el método Ganzfeld. Comenzamos con una descripción de la metodología de investigación utilizada en el área:1) Los primeros estudios Ganzfeld realizados y publicados desde 1974 hasta 1981, y sus posibles debilidades motodológicas; 2) la evidencia mostrada por los estudios de Autoganzfeld, llevados a cabo por Honorton y sus colaboradores en el Psychophysical Research Laboratory (Princeton), de 1983 a 1989, y publicados en el Psychological Bulletin en 1994; y 3) los estudios de la nueva generación, desde 1986, y el fracaso observado en la replicación del efecto. También, analizamos una serie de consideraciones, señaladas por los investigadores en respuesta a las críticas, a tener en cuenta a la hora de evaluar la evidencia experimental del fenómeno. Para finalizar, concluimos que, aunque los resultados hasta ahora obtenidos son indicativos de la existencia de un mecanismo anómalo de transferencia de información, investigación orientada hacia la evidencia (proof-oriented research) es actualmente conveniente en el área (AU)
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Humanos , Historia del Siglo XX , Parapsicología/métodos , Parapsicología/historia , Trastornos del Conocimiento/psicología , Medicina Basada en la EvidenciaRESUMEN
Os autores apresentam alguns casos de degeneraçäo macular da idade que foram estudados através da vídeo angiografia digital com a indocianina verde (ICGV). Os resultados sugerem ser a ICGV um exame importante e adjunto à angiografia fluoresceínica para estudar a circulaçäo da coróide, particularmente na identificaçäo da CNV oculta, transformando-a em clássico, permitindo um tratamento eficaz da mesma