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1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 135(1S): S55-S57, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29396223

RESUMEN

During the 2017 IFOS international congress in Paris, a roundtable discussion on the topic of functional and aesthetic rhinoplasty was organised. Five experts, from the five continents and renown in the field of rhinoplasty, were brought together to discuss the issue from an international perspective and to put forward a consensus or on the contrary practical differences. Five questions were put to the experts beforehand to guarantee independent answers, which were then discussed during the roundtable. The questions were the following: - What are the age limits for achieving a rhinoplasty? - Do you use objective measurements before, during and after surgery? (facial landmarks, airflow, peroperative measurements) - How do you manage the preoperative general information and computer imaging of the patient? - What are the indications in your practice to perform a CT-scan or endoscopic examination before doing a rhinoplasty? - What kind of graft or prosthesis do you use for an augmentation rhinoplasty? This paper offers a synthesis of the roundtable based on the experts' answers to the different questions.


Asunto(s)
Rinoplastia/normas , Estética , Humanos , Internacionalidad
2.
Biol Sport ; 34(1): 57-61, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28416899

RESUMEN

As children's natural activity patterns are highly intermittent in nature, and characterised by rapid changes from rest to vigorous physical activity, discontinuous exercise tests may be considered ecologically valid for this population group. This study compared the peak physiological responses from a discontinuous and continuous graded exercise test (GXT_D, GXT_C, respectively) during treadmill exercise in children. Twenty-one healthy children (9.6 ± 0.6 y) completed GXT_D and GXT_C in a randomised order, separated by 72-hours. Following each GXT, and after a 15-minute recovery, participants completed a verification test at 105% of the velocity attained at peak oxygen consumption (VO2peak). There were no differences in VO2peak (55.3 ± 8.2 cf. 54.4 ± 7.6 mL·kg-1·min-1) or maximal heart rate (202 ± 10 cf. 204 ± 8 b·min-1) between GXT_C and GXT_D, respectively (P>.05). Peak running speed (10.7 ± 0.9 cf. 12.1 ± 1.3 km·h-1) and respiratory exchange ratio (1.04 ± 0.05 cf. 0.92 ± 0.05) were however different between tests (P<.001). Although similar peak physiological values were revealed between GXT_C and the corresponding verification test (P>.05), VO2peak (53.3 ± 7.3 mL·kg-1·min-1) and heart rate (197 ± 13 b·min-1) were significantly lower in the GXT_D verification test (P<.05). In conclusion, a discontinuous GXT is an accurate measure of VO2peak in children aged 8 to 10 years and may be a valid alternative to a continuous GXT, despite its longer duration.

3.
Org Lett ; 18(2): 284-7, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26741730

RESUMEN

Oxidative allene amination provides rapid access to densely functionalized amine-containing stereotriads through highly reactive bicyclic methyleneaziridine intermediates. This strategy has been demonstrated as a viable approach for the construction of the densely functionalized aminocyclitol core of jogyamycin, a natural product with potent antiprotozoal activity. Importantly, the flexibility of oxidative allene amination will enable the syntheses of modified aminocyclitol analogues of the jogyamycin core.


Asunto(s)
Pactamicina/análogos & derivados , Pactamicina/síntesis química , Alcadienos/química , Aminación , Aminas/química , Estructura Molecular , Oxidación-Reducción , Pactamicina/química , Pactamicina/farmacología , Estereoisomerismo , Streptomyces/química
4.
J Laryngol Otol ; 130 Suppl 1: S32-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26304159

RESUMEN

BACKGROUND: The internationally recognised American Joint Committee on Cancer (tumour-node-metastasis) staging system utilises tumour size to determine stage. Other factors (i.e. tumour depth) may provide additional prognostic information. METHOD: A thorough retrospective analysis was performed of 68 patients with primary lip squamous cell carcinoma operated on or discussed by the Darling Downs Health Service between 2005 and 2013. RESULTS: Twelve patients developed lymphatic spread. There was a statistically significant increased risk of nodal metastasis in: patients with tumours of increased thickness (U = 103.50; degrees of freedom = 68; p < 0.001), those with a larger overall tumour size (U = 163.50; degrees of freedom = 68; p = 0.005) and patients living further from the treatment centre (U = 199.00; degrees of freedom = 68; p = 0.018). CONCLUSION: It may be reasonable that other factors are considered for staging of lip squamous cell carcinomas, in combination with tumour-node-metastasis staging. Depth of invasion may have utility in prognosis and treatment; however, larger prospective analysis needs to be performed. Patients living in a more rural setting presented with more advanced disease, suggesting an ongoing rural-metropolitan gap in healthcare.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Neoplasias de los Labios/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Queensland , Estudios Retrospectivos , Factores de Riesgo , Población Rural , Carcinoma de Células Escamosas de Cabeza y Cuello , Adulto Joven
5.
J Am Chem Soc ; 134(39): 16131-4, 2012 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-22985198

RESUMEN

A Cu(I)-catalyzed 1,3-halogen migration reaction effectively recycles an activating group by transferring bromine or iodine from a sp(2) to a benzylic carbon with concomitant borylation of the Ar-X bond. The resulting benzyl halide can be reacted in the same vessel under a variety of conditions to form an additional carbon-heteroatom bond. Cross-over experiments using an isotopically enriched bromide source support intramolecular transfer of Br. The reaction is postulated to proceed via a Markovnikov hydrocupration of the o-halostyrene, oxidative addition of the resulting Cu(I) complex into the Ar-X bond, reductive elimination of the new sp(3) C-X bond, and final borylation of an Ar-Cu(I) species to turn over the catalytic cycle.


Asunto(s)
Cobre/química , Halógenos/química , Boro/química , Catálisis , Oxidación-Reducción , Polimerizacion , Estireno/química
6.
Chemistry ; 18(30): 9391-6, 2012 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-22718528

RESUMEN

Benzylic functionalization is a convenient approach towards the conversion of readily available aromatic hydrocarbon feedstocks into more useful molecules. However, the formation of carbanionic benzyl species from benzyl halides or similar precursors is far from trivial. An alternative approach is the direct reaction of a styrene with a suitable coupling partner, but these reactions often involve the use of precious-metal transition-metal catalysts. Herein, we report the facile and convenient generation of reactive benzyl anionic species from styrenes. A Cu(I)-catalyzed Markovnikov hydroboration of the styrenic double bond by using a bulky pinacol borane source is followed by treatment with KOtBu to facilitate a sterically induced cleavage of the C-B bond to produce a benzylic carbanion. Quenching this intermediate with a variety of electrophiles, including CO(2), CS(2), isocyanates, and isothiocyanates, promotes C-C bond formation at the benzylic carbon atom. The utility of this methodology was demonstrated in a three-step, two-pot synthesis of the nonsteroidal anti-inflammatory drug (±)-flurbiprofen.


Asunto(s)
Compuestos de Bencilo/química , Flurbiprofeno/química , Flurbiprofeno/síntesis química , Estirenos/química , Catálisis , Estructura Molecular
7.
Org Lett ; 14(1): 280-3, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22182178

RESUMEN

Propargylic amines are important intermediates for the synthesis of nitrogen-containing heterocycles. The insertion of a nitrene into a propargylic C-H bond has not been explored, despite the attention directed toward the Rh-catalyzed amination of other types of C-H bonds. In this communication, the conversion of a series of homopropargylic carbamates to propargylic carbamates and aminated allenes is described.

8.
Org Lett ; 13(8): 1924-7, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21438516

RESUMEN

The oxidative functionalization of olefins is a common method for the formation of vicinal carbon-heteroatom bonds. However, oxidative methods to transform allenes into synthetic motifs containing three contiguous carbon-heteroatom bonds are much less developed. This paper describes the use of bicyclic methylene aziridines (MAs), prepared via intramolecular allene aziridination, as scaffolds for functionalization of all three allene carbons.


Asunto(s)
Alcadienos/química , Aziridinas/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Metano/química , Estructura Molecular
9.
Artículo en Inglés | MEDLINE | ID: mdl-17695711

RESUMEN

Non-phosphine-containing cyclopalladated N-heterocycles possessing either sp2 C-Pd(II) or sp3 C-Pd(II) bonds and simple Pd(II) salts are precursors of Pd(0) nanoparticles whose initial morphology is dependent on the nature of the precursor. Addition of polyvinylpyrrolidone (pvp) dramatically increases catalyst lifetime. Nanoparticle generation can be achieved at ambient temperature in the presence of carbon monoxide by a process akin to the water-gas shift reaction. Allene also lowers the temperature required for nanoparticle generation. 3-Component catalytic cascades employing one or both of these substrates provide access to a variety of 5- and 6-membered N-heterocycles including isoindolones, N-aminoisoindolones, phthalazones, dihydroisoquinolines, and isoquinolones.


Asunto(s)
Indoles/química , Nanopartículas del Metal/química , Nanopartículas/química , Nanotecnología/métodos , Paladio/química , Monóxido de Carbono/química , Catálisis , Química Orgánica/métodos , Modelos Químicos , Conformación Molecular , Estructura Molecular , Compuestos Organometálicos , Temperatura
10.
Otolaryngol Clin North Am ; 34(3): 583-600, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11447004

RESUMEN

Reconstruction of the forehead and temple region poses special aesthetic challenges for maintaining eyebrow symmetry and hairline. The preservation of motor and sensory function is also important. There are a wide variety of techniques available to the reconstructive surgeon, and these methods are compared and discussed with specific reference to the forehead and temple region.


Asunto(s)
Frente/cirugía , Procedimientos de Cirugía Plástica/métodos , Hueso Temporal/cirugía , Humanos , Colgajos Quirúrgicos
11.
Chem Commun (Camb) ; (19): 1968-9, 2001 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-12240243

RESUMEN

Heating alkyl vinyl ketones and N-tert-butylarylmethylideneamine N-oxides in the presence of HfCl4 results in the formation of 4-methylene-4,5-dihydroisoxazoles in good yield.

12.
Chem Commun (Camb) ; (18): 1712-3, 2001 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-12240278

RESUMEN

A 3-component cascade synthesis of bis(2-arylallyl) tertiary amines from aryl iodide, allene and primary aliphatic amines is described; chiral amines give analogous products with no detectable racemisation; mixtures of two different aryl iodides can be utilised to give the mixed tertiary amines as the sole, or major, product; the reaction is sensitive to stereoelectronic effects which lead to mono(2-arylallyl) secondary amines.

15.
J Laryngol Otol ; 112(8): 779-81, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9850324

RESUMEN

Meningo-encephalocoeles of the skull base may present as spontaneous cerebrospinal fluid rhinorrhoea or acute meningitis. Previous approaches to midline skull base lesions have been either intracranial, via a craniotomy, or by transfacial or endoscopic extracranial approaches. This paper presents an alternative approach to lateral sphenoid sinus encephalocoeles through a Le Fort I osteotomy approach.


Asunto(s)
Encefalocele/cirugía , Meningocele/cirugía , Seno Esfenoidal/diagnóstico por imagen , Encefalocele/diagnóstico por imagen , Encefalocele/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Maxilar/cirugía , Meningocele/diagnóstico por imagen , Meningocele/patología , Persona de Mediana Edad , Osteotomía Le Fort , Tomografía Computarizada por Rayos X
16.
Aust N Z J Surg ; 68(9): 630-4, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9737256

RESUMEN

Supracricoid laryngectomy is a new development in the treatment of laryngeal cancer in Australia. It allows the removal of both vocal cords, vestibular folds, and the entire thyroid cartilage including the paraglottic space without the loss of laryngeal function. This technique may offer a significant advance in the treatment of squamous cell carcinoma of the larynx. This paper reviews the surgical management of laryngeal cancer and discusses this new technique with modifications, indications for its use and the advantages of supracricoid laryngectomy. Case reports of seven patients operated on in our institution are included.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Cartílago Cricoides/cirugía , Neoplasias Laríngeas/cirugía , Laringectomía/métodos , Carcinoma de Células Escamosas/fisiopatología , Estudios de Seguimiento , Humanos , Neoplasias Laríngeas/fisiopatología , Tiempo de Internación , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Vestíbulo del Laberinto/cirugía , Pliegues Vocales/cirugía
17.
J Vet Pharmacol Ther ; 19(2): 135-41, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8735422

RESUMEN

The interaction of sulphamethazine (SMZ) with pig plasma proteins and albumin was studied by ultrafiltration and equilibrium dialysis. Binding to pig plasma proteins was monophasic (affinity approximately 9.0 mol/L x 10(3)) and the main binding protein was albumin. At 37 degrees C and pH 7.4, the affinity of SMZ for albumin was about 8.0 mol/L x 10(3) and the number of binding sites was estimated as 1.4. Increasing the temperature from 4 to 45 degrees C resulted in a seven-fold decrease in affinity, and increasing pH from 6.0 to 8.0 enhanced affinity for pig albumin ten-fold. The free energy of binding (-delta G) and enthalpy change (-delta H) were around 5.5 and 5.1 Kcal/mol, respectively. The total entropy change (delta S) was small and positive, around 2 cal/mol/degree K. Studies with the fluorescent probes warfarin and dansylsarcosine, suggest that these bind to separate sites on porcine albumin. SMZ displaced both probes and inhibited the deacetylation of p-nitrophenyl acetate by pig albumin. We conclude that: (1) binding of SMZ to pig plasma proteins and albumin is weak; (2) the interaction with albumin is exothermic and enthalpy driven, and (3) pig albumin, like other mammalian albumins, appears to possess discrete binding sites for warfarin and dansylsarcosine. SMZ interacts with both these loci.


Asunto(s)
Antiinfecciosos/metabolismo , Proteínas Sanguíneas/metabolismo , Albúmina Sérica/metabolismo , Sulfametazina/metabolismo , Porcinos/sangre , Análisis de Varianza , Animales , Antiinfecciosos/administración & dosificación , Antiinfecciosos/farmacocinética , Sitios de Unión , Compuestos de Dansilo/metabolismo , Colorantes Fluorescentes/metabolismo , Concentración de Iones de Hidrógeno , Masculino , Unión Proteica , Sarcosina/análogos & derivados , Sarcosina/metabolismo , Sulfametazina/administración & dosificación , Sulfametazina/farmacocinética , Porcinos/metabolismo , Termodinámica , Warfarina/metabolismo
19.
Science ; 269(5232): 1893-4, 1995 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-17820248
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