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Biomedical subjects

Peter Scott

Publications and source records attributed to Peter Scott.

13 recordsLinked to original sources
PubMed2003

The ethical implications of the new research paradigm.

Research is now an increasingly heterogeneous activity involving an expanded range of new actors and stake-holders and employing an eclectic range of epistemologies and methodologies. The emergence of these new research paradigms--and, in particular, of so-called 'Mode 2' knowledge production that is highly contextualised and socially distributed--raises new and challenging ethical issues and also important questions about the autonomy of science and the social responsibilities of scientists.

Ethics, Research↗
PubMed2003

Implementing an office system to improve primary care management of depression.

Studies have shown that many patients treated for depression in primary care settings do not achieve the outcomes demonstrated to be possible in randomized controlled trials. In general, multifaceted interventions have been more successful than single focus interventions in improving care of depression in this setting. This article reports on the implementation of such a mulitfaceted intervention in primary care practices. Part of the strategy in this case is to introduce the intervention through an intermediary organization that has a relationship with the practices and has a quality improvement infrastructure to support the implementation and help to sustain changes.

Case Management↗
PubMed2002

Efficient predetermination of chirality-at-zirconium.

Only one of eight possible diastereomers of the organometallic chiral-at-metal complex [ZrL2(CH2Ph)2] (L = a bidentate, chiral non-racemic pyrdine alcoholate) is observed by NMR spectroscopy in the slow exchange regime.

Journal Article↗
PubMed2002

Enantioselective aziridination using copper complexes of biaryl Schiff bases.

Racemic 2,2'-diamino-6,6'-dimethylbiphenyl is resolved using simulated moving bed chromatography, and the absolute configuration of the enantiomers is confirmed via the X-ray crystal structure of a derivative. The diamine is condensed with a range of aldehydes to give bidentate aldimine proligands L. Molecular structures of the complexes formed between L and Cu(I) fall into two classes; bimetallic double helices ([Cu(2)L(2)](2+)) and monometallic ([CuL](+)). The latter are strikingly more efficient in the aziridination of alkenes than are the former in terms of rate, turnover, and enantioselection. In particular, the imine ligand formed from the diamine and 2,6-dichlorobenzaldehyde gives, in combination with Cu(I) or Cu(II), up to 99% ee in the aziridination of 6-acyl-2,2-dimethylchromene and 88-98% ee for a range of cinnamate esters. Styrenic and other alkenes are converted with lower selectivities (5-54%). The catalytic system shows a linear response in product ee to catalyst ee, and the product ee does not vary significantly during the reaction. UV spectrophotometric investigations indicate that conversion of Cu(I) to Cu(II) is not essential for catalysis but that Cu(II) is probably also a competent system.

Journal Article↗
PubMed2002

Problems and solutions for alkene polymerisation catalysts incorporating Schiff-bases; migratory insertion and radical mechanisms of catalyst deactivation.

Steric blocking of an intramolecular 1,2-migratory insertion reaction of a zirconium salicylaldiminato complex leads to a long-lived catalyst for ethene polymerisation, but promotes a new radical catalyst decomposition mechanism in certain instances; kinetic and thermodynamic parameters for both pathways have been established.

Journal Article↗
PubMed2002

Culdoscopy using an optical cannula.

OBJECTIVE: To describe a technique for inserting an endoscope through the posterior vaginal fornix under direct vision using an optical cannula. DESIGN: Prospective case study. SETTING: University Department of Obstetrics & Gynecology. PATIENT(S): Patients with infertility referred for investigation in secondary care. INTERVENTION(S): Insertion of culdoscope using an optical cannula. MAIN OUTCOME MEASURE(S): Successful introduction of the culdoscope. RESULT(S): Sixteen of 20 patients had successful introduction of the optical cannula. There were no reported complications. CONCLUSION(S): Insertion of a culdoscope into the cul-de-sac can be done under visual control and this may reduce the risks of complications associated with blind insertion using a modified Veress needle.

Adult↗
PubMed2002

Development of a novel method of female sterilization: II. Retention of tubal screws in patients undergoing simultaneous laparoscopic sterilization.

BACKGROUND AND OBJECTIVES: This study was a long-term follow-up of patients in whom hysteroscopic tubal screws had been applied at the time of laparoscopic sterilization. METHODS: Tubal screw application was performed before laparoscopic Filshie clip application. Follow-up ultrasonography was arranged 3, 6, and 9 months postoperatively to confirm retention. The tubal screws were removed hysteroscopically between 12 and 20 months after sterilization under local or light general anesthesia. RESULTS: Thirty-five women agreed to take part in the study. For the purpose of analysis, these patients were divided into an initial group (cases 1-20, group A) and a later group (cases 21-35, group B). Twenty-three patients had 41 tubal screws inserted (18 women had bilateral screw application). Twenty tubal screws were removed from 13 patients between 9 and 20 months after insertion, one screw remained in situ, and 20 screws had previously been extruded. Life table analysis plots demonstrated a marked but nonsignificant difference (P = .163) in the duration of tubal screw retention between the initial patients (group A) and the later patients (group B): 46.7% versus 76.9% at 6 months and 33% versus 61.5% at 12 months (P = .09 and P = .11, respectively). CONCLUSIONS: Our experience demonstrated improved application and retention with experience and refinement of the equipment; however, retention of the tubal screws, even in the later stages of development, was poor. A relatively noninvasive method of female sterilization remains the ideal, and further refinements are required.

Fallopian Tubes↗
PubMed2002

Maxillonasal dysplasia (Binder syndrome): a lateral cephalometric assessment.

Binder syndrome or maxillonasal dysplasia was first described by Binder in 1962, and is a disorder characterised by nasomaxillary hypoplasia. The records of 33 patients who had been diagnosed clinically with Binder syndrome at the Royal Children's Hospital of Melbourne were examined. Of these 33 patients, 14 were selected because they met the incusion criteria: that they had not had prior surgical and/or orthodontic treatment, and that high-quality lateral cephalometric radiographs were available. The craniofacial morphology of these patients was determined on lateral cephalometric radiographs and compared with published age- and sex-matched norms. In agreement with published studies, the anteroposterior lengths of the anterior cranial base and maxilla were reduced, and the majority of patients had a Class III skeletal relationship. Although the lower incisors tended to be prominent, both overjet and overbite 'ell within the ranges for the normal population. Despite the fact that the orthodontic and surgical treatment for patients with Binder syndrome is normally carried out within specialised units, clinicians should be aware of the variety of ways in which this condition may present.

Adolescent↗
PubMed1999

Complexes of Triamidoamines with the Early Actinides. Synthetic Routes to Monomeric Compounds of Tetravalent Uranium and Thorium Containing Halide and Amide Ligands.

The reaction of the lithiated triamidoamine [Li(3)(NN'(3))(THF)(3)] [NN'(3) = N(CH(2)CH(2)NSiMe(2)Bu(t))(3)] with AnCl(4) (An = U, Th) followed by sublimation gives monomeric [An(NN'(3))Cl]. Reaction of these complexes with SiMe(3)X (X = Br, I) gives [An(NN'(3))X]. The amido derivatives [An(NN'(3))(NEt(2))] are prepared from H(3)(NN'(3)) and [U(NEt(2))(4)] and from [Th(NN'(3))Cl] and [Li(NEt(2))]. In each case, the complexes [U(NN'(3))X] (X = Cl, Br, I, NEt(2)) are shown by X-ray crystallography to contain a triamidoamine ligand disposed with 3-fold symmetry about the metal center. The structures are distorted from trigonal bipyramidal by displacement of the uranium atoms out of the equatorial plane of the three amido nitrogen atoms by ca. 0.8 Å. The ligand backbone is distorted in such a manner as to cause the tert-butyldimethylsilyl groups to encircle the equatorial plane of the metal atom rather than surround the apical coordination site as is observed in the transition metal complexes of this type. Variation of the auxiliary ligand has little effect on the orientation, bond lengths, and angles within the (triamidoamine)uranium fragment. The tert-butydimethysilyl-substituted triamidoamine ligand is thus ideally suited for coordination to large metals since it stabilizes the formation of 3-fold symmetric structures while also allowing reactivity at the fifth coordination site.

Journal Article↗
PubMed1997

Alkoxide and Aryloxide Derivatives of a (Triamidoamine)uranium Complex.

The (triamidoamine)uranium chloride complex [{U(NN(3))(&mgr;-Cl)}(2)] [NN(3) = N(CH(2)CH(2)NSiMe(3))(3)] reacts with alkali metal alkoxides and aryloxides to give a range of complexes [U(NN(3))(OR)] (R = Bu(t), t-C(4)F(9), Ph, 2,6-Bu(t)(2)-4-MeC(6)H(2)). Crystallographic investigations (including the molecular structure of the perfluoro-tert-butoxido derivative [U(NN(3))(O-t-C(4)F(9))]), molecular weight determinations, and NMR spectroscopic data are consistent with these molecules being monomeric with a 3-fold symmetric arrangement of the triamidoamine fragment. The three turquoise ate complexes [U(NN(3))(OR)(OR')Li(THF)(n)()] (R, R' = Bu(t) or Ph), are prepared by reaction of the corresponding uranium alkoxides with lithium phenoxide or tert-butoxide. The complex with R = Ph, R' = Bu(t), n = 1 is shown by X-ray crystallography to have a capped trigonal bipyramidal structure. A lithium atom is incorporated into the ligand sphere by coordination to an amido nitrogen and a tert-butoxido oxygen. The mixed alkoxide ate complex [U(NN(3))(OBu(t))(OPh)Li(THF)] gives only [U(NN(3))(OBu(t))] on heating in vacuo. The one-electron oxidation of these ate complexes to the three neutral pentavalent compounds [U(NN(3))(OR)(OR')] (R, R' = Bu(t) or Ph) has been characterized by cyclic voltammetric studies and performed on the chemical scale by reaction with [FeCp(2)][PF(6)].

Journal Article↗