Démarche systématique d’analyse dysfonctionnelle en radiothérapie

PurposeWe previously presented a systematic and structured approach to acquire an accurate functional model of the patient's process in radiotherapy. This approach relied on new functional structuring patterns, derived from system engineering and knowledge engineering. Additionally, we propose a complementary methodical process for the dysfunctional analysis of the obtained functional model.Materials and methodsThe procedure is based on joint implementation of two qualitative methods named “Failure modes and effects analysis” (FMEA) and “Hazard and operability” (HazOp).ResultsAll the technical, the human and the organizational dimensions of the patient's process are pooled in a unique, exhaustive and detailed dysfunctional analysis. The application of this systematic approach within a particular institution can precisely identify the risks incurred by patients in care, but also highlight the logical sequence between precursor events and incidents.ConclusionThe dysfunctional analysis presented in this document will be used for the development still in process of quantified risk models.     

Modélisation fonctionnelle adaptée à l’analyse des risques en radiothérapie

PurposeThis document presents a systematic and structured approach for functional modeling for risk analysis in radiotherapy, aiming to reconcile the need, on one hand, for a method that can be applied generally and, on the other hand, for a method that provides a highly precise model.Materials and methodsThe approach relies on new functional structuring patterns and flux analysis, derived from system engineering and knowledge engineering.ResultsThe method affords strong support for the development of detailed models of the patient's process through a department of radiotherapy. Lack of structure of the actual process in a particular department may be easily identified leading to the development of specific procedures for the improvement of security.ConclusionModeling approach derived from engineering may be used for functional modeling for risk analysis in radiotherapy.     

Common bile duct calculi: updated experience with dissolution with methyl tertiary butyl ether

The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.     

Enhancement of chemotactic factor-stimulated neutrophil oxidative metabolism by leukotriene B4

Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci.     

Keggin‐Type Polyoxometalate ([PMo12O40]3−) in Radical Initiating Systems: Application to Radical and Cationic Photopolymerization Reactions

New photoinitiating systems based on a polyoxometalate (POM) are proposed: phosphomolybdic acid in combination with silane, germane, or iodonium salt can be used to generate silyl, germyl, or phenyl radicals as well as silylium cations. The photochemical mechanisms are studied by steady‐state photolysis and electron spin resonance. The phosphomolybdic acid/silane/iodonium salt system can initiate either the radical photopolymerization of acrylates or the cationic photopolymerization of epoxides. The synthesis of interpenetrated polymer networks can also be carried out. The mechanical properties of the synthesized polymers are affected by the presence of POM in the matrix, as shown by their dynamic mechanical analysis (DMA).

     

Testing the Effectiveness of Motivational Interviewing as a Weight Reduction Strategy for Obese Cardiac Patients: A Pilot Study

Background

Obesity has reached epidemic proportions in the USA and is a particular threat to those with coronary disease. Motivational interviewing (MI) is a client-centered, directive method for enhancing intrinsic motivation to change by exploring and resolving ambivalence about altering behavior.

Purpose

This study examined the efficacy of MI compared to nutritional counseling for weight loss in a small sample of obese cardiac patients.

Method

Participants were assigned to either MI or to nutrition counseling and followed up over 3 months. Trained undergraduate students delivered the MI intervention.

Results

There were significant reductions in weight in women in the MI intervention, but not in men.

Conclusion

The results suggest that MI may be effective for obese female cardiac patients, in particular, even when delivered by nonprofessional interviewers. Limitations of the study include a small sample size, nonrandomized assignment to conditions, and attrition over time.     

Posttraumatic Stress Symptom Trajectories Among Children Exposed to Violence

Little research has examined the developmental course of posttraumatic stress symptoms (PTSS) in children. The current study aimed to identify developmental trajectories of PTSS in childhood and to examine predictors of symptom presentation in 1,178 children from the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN) studies, a consortium of studies focusing on the causes and effects of child maltreatment. Most children had a history of documented reports with Child Protective Services (CPS) and all were identified as living in high‐risk environments. Using group‐based trajectory modeling, 3 unique developmental trajectories were identified: Resilient, Clinical‐Improving (PTSS in the clinical range at baseline then declining over time), and Borderline‐Stable (chronically subclinical PTSS). Children in the Clinical‐Improving group were more likely than children in the Resilient group to have reports of physical abuse (RRR = 1.76), emotional abuse (RRR = 2.55), neglect (RRR = 1.57), and exposure to violence at home and in the community (RRR = 1.04). Children in the Borderline‐Stable group were more likely than children in the Resilient group to have a CPS history of neglect (RRR = 2.44) and exposure to violence at home and in the community (RRR = 1.04). Many children living in high‐risk environments exhibit resilience to PTSS, but exposure to witnessed violence and neglect appear to put children at chronic risk for poor adjustment. These children may require more intensive, integrated clinical services that attend to multiple adverse experiences.