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1.
J Phys Chem A ; 122(14): 3572-3582, 2018 Apr 12.
Article in English | MEDLINE | ID: mdl-29522684

ABSTRACT

The photoswitching and competitive processes of two photochromic dithienylethenes (DTEs) functionalized at both sides with 2-ureido-4[1H]-pyrimidone (UPy) quadruple hydrogen-bonding recognition patterns have been investigated with NMR experiments, ultrafast spectroscopy, and density functional theory (DFT) calculations. The originality of these molecules is their ability to form large supramolecular assemblies induced by light for the closed form (CF) species while the open form (OF) species exist as small oligomers. Photochromic parameters have been determined and photochemical pathways have been rationalized with clear distinction between the antiparallel (OF-AP) and parallel (OF-P) species. A new photocyclization pathway via triplet manifold has been evidenced. The effect of the supramolecular assembly on the photochemical response is discussed. Unlike the photoreversion process, which is unaffected by supramolecular assembly, rate constants of the photocyclization reaction and intersystem crossing process are sensitive to the presence of small OF oligomers.

2.
Clin Otolaryngol ; 43(1): 317-324, 2018 02.
Article in English | MEDLINE | ID: mdl-28950049

ABSTRACT

OBJECTIVES: To explore the incidence and treatment pattern of head and neck cancer in different age groups. DESIGN: Cohort study. SETTING: Netherlands Cancer Registry. PARTICIPANTS: All new primary head and neck cancer cases diagnosed between 2010 and 2014 were included and categorised into different age groups. MAIN OUTCOME MEASURES: Tumour site, stage, treatment modality, location of diagnosis and treatment. RESULTS: The study population was composed of 11 558 tumours. Oral cancer was the most common primary site (31%), followed by laryngeal (25%) and oropharyngeal cancer (22%). Ninety-six per cent of the entire study population was diagnosed and/or treated in a certified head and neck oncology centre which was lower in the 80+ population (92%). Multimodality treatment was less frequently applied with increasing age (eg oral cavity: 17% in 80+ vs 34% in 60-; P < .001). The percentage of patients not receiving tumour-directed treatment increased with age (eg oropharyngeal cancer: 25% in 80+ vs 6% in 80-; P < .001). CONCLUSIONS: This study confirms that less multimodal and tumour-directed treatment is applied with the increasing age of head and neck cancer patients.


Subject(s)
Head and Neck Neoplasms/epidemiology , Neoplasm Staging , Population Surveillance/methods , Registries , Risk Assessment/methods , Age Distribution , Age Factors , Aged , Aged, 80 and over , Female , Follow-Up Studies , Head and Neck Neoplasms/diagnosis , Humans , Incidence , Male , Middle Aged , Netherlands/epidemiology , Retrospective Studies , Sex Distribution , Time Factors
3.
Chem Commun (Camb) ; 52(76): 11370-11373, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27711321

ABSTRACT

The straightforward synthesis of a new Cu(i) metal-rich small metallacycle is presented. This compound is luminescent in the solid state with an emission quantum yield of 72% at room temperature and displays a pronounced reversible red-shift of its emission spectra upon cooling. Quantum chemical calculations reveal that these properties are governed by important geometrical relaxations that imply the formation of cuprophilic interactions at the excited states.

4.
Clin Otolaryngol ; 40(5): 474-82, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25754107

ABSTRACT

OBJECTIVES: Careful selection of patients eligible for extensive head and neck cancer surgery is extremely important. A reliable predictor for postoperative outcomes in the vulnerable elderly population is not yet available. The concept of frailty describes a clinical state of increased vulnerability and can be assessed using frailty tests, such as the Groningen Frailty Indicator. In the current study, the influence of Groningen Frailty Indicator-measured frailty on clinical outcome was investigated in elderly patients surgically treated for head and neck cancer. DESIGN: Retrospective, explorative cohort study. SETTING: Tertiary referral centre. PARTICIPANTS: A total of 90 patients of 65 years and older receiving surgical treatment for head and neck cancer with different primary sites. MAIN OUTCOME MEASURES: The influence of frailty (Groningen Frailty Indicator) on postoperative complications (Clavien-Dindo classification), subjective postoperative experience of both patient and surgeon and survival were analysed. RESULTS: A total of 36 patients were considered as frail (40%). Postoperative complications could not be predicted by frailty status. However, the Groningen Frailty Indicator dimension 'health problems' was a significant predictor for postoperative complications (P = 0.020). Unlike age and comorbidity, frailty was associated with a poor subjective patients' experience of the postoperative recovery (P < 0.01). Although not statistically significant, survival analysis showed a worse 5-year overall survival in the frail group (33%) versus the non-frail group (74%). CONCLUSIONS: Analysis of frailty could identify elderly patients who might suffer more than expected during the postoperative period after head and neck cancer surgery. In this study, frailty was not identified as a new predictor of complications after head and neck cancer surgery.


Subject(s)
Frail Elderly , Head and Neck Neoplasms/surgery , Postoperative Complications , Skin Neoplasms/surgery , Treatment Outcome , Aged , Analysis of Variance , Female , Head and Neck Neoplasms/mortality , Humans , Kaplan-Meier Estimate , Male , Neoplasm Staging , Prognosis , Retrospective Studies , Skin Neoplasms/mortality
5.
Hernia ; 16(1): 77-89, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21805341

ABSTRACT

INTRODUCTION: Abdominal wall defects and incisional hernias represent a challenging problem. Currently, several commercially available biologic prostheses are used clinically for hernia repair. We compared the performance and efficacy of two non-crosslinked meshes in ventral hernia repair to two crosslinked prostheses in a rodent model. METHODS: Animals were divided into 12 groups (4 matrix types and 3 termination time-points per matrix). A ventral defect was carefully created and overlapped with the biologic prosthesis. RESULTS: Major complications were seroma induction (3 mesh types), implant extrusion (1 mesh type), severe inflammatory and immune responses (non-crosslinked mesh), fibrosis and mineralisation (3 mesh types). After inflammation resolution, 3 of the matrices tested supported hernia healing but with marked tissue and temporal differences. AlloDerm(®*) and Surgisis Gold™ showed tissue reactivity with the host and a rapid rate of matrix remodelling. Bard CollaMend™(*) Implant proved to be inept for hernia repair under the conditions tested. Permacol™ biological implant integration with host tissue increased over time, supporting hernia healing with strength of tissue, and appears to be a safe prosthetic material for ventral hernia repair based on the results of this rodent study.


Subject(s)
Abdominal Wall/pathology , Biocompatible Materials , Hernia, Ventral/surgery , Surgical Mesh , Animals , Biocompatible Materials/adverse effects , Collagen/adverse effects , Collagen/therapeutic use , Fibrosis , Herniorrhaphy/adverse effects , Inflammation/etiology , Inflammation/pathology , Male , Materials Testing , Prosthesis Failure , Rats , Rats, Sprague-Dawley , Seroma/etiology , Surgical Mesh/adverse effects , Tensile Strength , Time Factors
6.
Clin Pharmacol Ther ; 83(3): 443-51, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17687274

ABSTRACT

As oversedation is still common and significant variability between and within critically ill patients makes empiric dosing difficult, the population pharmacokinetics and pharmacodynamics of propofol upon long-term use are characterized, particularly focused on the varying disease state as determinant of the effect. Twenty-six critically ill patients were evaluated during 0.7-9.5 days (median 1.9 days) using the Ramsay scale and the bispectral index as pharmacodynamic end points. NONMEM V was applied for population pharmacokinetic and pharmacodynamic modeling. Propofol pharmacokinetics was described by a two-compartment model, in which cardiac patients had a 38% lower clearance. Severity of illness, expressed as a Sequential Organ Failure Assessment (SOFA) score, particularly influenced the pharmacodynamics and to a minor degree the pharmacokinetics. Deeper levels of sedation were found with an increasing SOFA score. With severe illness, critically ill patients will need downward titration of propofol. In patients with cardiac failure, the propofol dosages should be reduced by 38%.


Subject(s)
Critical Illness , Models, Chemical , Propofol/pharmacology , Propofol/pharmacokinetics , Severity of Illness Index , Adult , Aged , Aged, 80 and over , Critical Illness/therapy , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , Propofol/blood , Time Factors
7.
Syst Biol (Stevenage) ; 153(3): 105-19, 2006 May.
Article in English | MEDLINE | ID: mdl-16984085

ABSTRACT

Compared evaluation of different methods is presented for estimating missing values in microarray data: weighted K-nearest neighbours imputation (KNNimpute), regression-based methods such as local least squares imputation (LLSimpute) and partial least squares imputation (PLSimpute) and Bayesian principal component analysis (BPCA). The influence in prediction accuracy of some factors, such as methods' parameters, type of data relationships used in the estimation process (i.e. row-wise, column-wise or both), missing rate and pattern and type of experiment [time series (TS), non-time series (NTS) or mixed (MIX) experiments] is elucidated. Improvements based on the iterative use of data (iterative LLS and PLS imputation--ILLSimpute and IPLSimpute), the need to perform initial imputations (modified PLS and Helland PLS imputation--MPLSimpute and HPLSimpute) and the type of relationships employed (KNNarray, LLSarray, HPLSarray and alternating PLS--APLSimpute) are proposed. Overall, it is shown that data set properties (type of experiment, missing rate and pattern) affect the data similarity structure, therefore influencing the methods' performance. LLSimpute and ILLSimpute are preferable in the presence of data with a stronger similarity structure (TS and MIX experiments), whereas PLS-based methods (MPLSimpute, IPLSimpute and APLSimpute) are preferable when estimating NTS missing data.


Subject(s)
Algorithms , Data Interpretation, Statistical , Gene Expression Profiling/methods , Models, Genetic , Models, Statistical , Oligonucleotide Array Sequence Analysis/methods , Computer Simulation , Sample Size
8.
Br J Anaesth ; 97(6): 832-4, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16997838

ABSTRACT

We report transection and embolization to the heart of a subclavian venous catheter in an immobilized and mechanical ventilated patient. The catheter tip was retrieved using a percutaneous method via the left femoral vein. Mechanical compression of the subclavian venous catheter at the costoclavicular area is termed pinch-off syndrome. It can be recognized by intermittent difficulties with drug injection, and chest wall swelling at the insertion site. The diagnosis can be confirmed by chest radiography with or without contrast administration. A more lateral approach of the subclavian vein is advocated to prevent compression.


Subject(s)
Catheterization, Central Venous/adverse effects , Catheterization, Central Venous/instrumentation , Critical Care , Embolism/etiology , Equipment Failure , Foreign-Body Migration/etiology , Humans , Male , Middle Aged , Respiration, Artificial
9.
Eur J Clin Pharmacol ; 56(1): 89-95, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10853884

ABSTRACT

OBJECTIVE: A new formulation of propofol 6% in Lipofundin MCT/LCT 10% (propofol 6% SAZN) has been developed in order to reduce the fat, emulsifier and volume load that is given during prolonged infusions of propofol. The pharmacokinetics, pharmacodynamics and safety characteristics of propofol 6% SAZN were investigated during a short-term infusion and compared with the commercially available product propofol 1% in Intralipid 10% (Diprivan-10) and propofol 1% in Lipofundin MCT/LCT 10% (propofol 1% SAZN). METHODS: In a randomised double-blind study, 24 male patients received a 5-h infusion of propofol at the rate of 1 mg/kg/h for sedation in the immediate postoperative period following coronary artery bypass surgery. RESULTS: The average pharmacokinetic parameter estimates of clearance (Cl), volume of distribution at steady state (Vd,ss), elimination half-life (t1/2,beta) and distribution half-life (t1/2,alpha) observed in the three groups were 28 +/- 1.1 ml/kg/min, 1.8 +/- 0.12 l/kg, 94 +/- 4.1 min and 3.1 +/- 0.26 min, respectively (mean +/- SEM, n = 24) and no significant differences were noted between the three formulations (P > 0.05). In one patient receiving propofol 6% SAZN, in two patients receiving propofol 1% SAZN and in three patients receiving Diprivan-10, the level of sedation was inadequate and additional sedative medication had to be given. In all other 18 patients, the level of sedation was adequate. The mean propofol concentration in these six inadequately sedated patients was lower than the adequately sedated patients (P = 0.015). The serum triglyceride concentrations were not significantly different between the groups studied. No adverse events occurred in any of the patients. CONCLUSIONS: The pharmacokinetics, pharmacodynamics and safety characteristics of propofol 6% SAZN are in good agreement with those of the 1% formulations. Propofol 6% SAZN therefore provides a useful alternative to the commercially available 1% formulation for short-term sedation in the intensive care unit. Expected advantages in long-term sedation of the 6% over 1% formulation are the subject of an ongoing study.


Subject(s)
Anesthetics, Intravenous/pharmacokinetics , Coronary Artery Bypass , Propofol/pharmacokinetics , Adult , Aged , Analysis of Variance , Anesthetics, Intravenous/blood , Chemistry, Pharmaceutical , Double-Blind Method , Humans , Male , Middle Aged , Propofol/blood
10.
Sante Publique ; 11(4): 493-501, 1999 Dec.
Article in French | MEDLINE | ID: mdl-10798175

ABSTRACT

This study presents a pedagogical work carried out with a group of 13 school nurses of the Academy of Rennes, as part of a course in survey methodology. A descriptive survey aiming to achieve a better understanding of experienced health status of nurses, and of its repercussions on the execution of their missions, was implemented during the course, as a result of the demand and the expertise of the participants. Overall, nurses report to be in good health. However, one can not underestimate the existence of a group at risk (5% of the sample) that often suffers somatic troubles accompanied by sleep disorders and anxiety, as these risks concern primarily permanent staff nurses working in boarding establishments, with half of them falling into this category. A demand for regular monitoring of their health was clearly expressed through the study. This may be the object of a subsequent study by an academic team.


Subject(s)
Health Status , Nursing Staff/psychology , Occupational Health , School Nursing/standards , Absenteeism , Adult , Burnout, Professional/prevention & control , Burnout, Professional/psychology , Female , France , Health Surveys , Humans , Job Satisfaction , Male , Middle Aged , Nursing Staff/statistics & numerical data , Surveys and Questionnaires
11.
Pharm Weekbl Sci ; 14(6): 360-4, 1992 Dec 11.
Article in English | MEDLINE | ID: mdl-1475176

ABSTRACT

A simple reversed-phase high pressure liquid chromatographic method was developed for the determination of cefuroxime in the serum of patients undergoing coronary artery bypass grafting. The serum was cleaned up with a 3.3% solution of perchloric acid in water. Cefalexine was used as an internal standard. Detection was made by a UV multi-wavelength detector. The optimum wavelength for cefuroxime is 275 nm. The absolute recovery of this method was 90.9%; the limit of quantification was 0.7 mg/l. This analytical method was used in a study to investigate the cefuroxime serum concentration--time curves in 26 patients undergoing coronary artery bypass grafting. It was found that one single dose is sufficient to obtain effective serum concentrations.


Subject(s)
Cefuroxime/blood , Coronary Artery Bypass , Adult , Aged , Calibration , Cefuroxime/administration & dosage , Cefuroxime/pharmacokinetics , Cefuroxime/therapeutic use , Chromatography, High Pressure Liquid , Female , Half-Life , Humans , Injections, Intravenous , Male , Middle Aged , Premedication
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