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Doctor-patient communication in different European health care systems: relevance and performance from the patients' perspective.

Our aim is to investigate differences between European health care systems in the importance attached by patients to different aspects of doctor-patient communication and the GPs' performance of these aspects, both being from the patients' perspective. 3658 patients of 190 GPs in six European countries (Netherlands, Spain, United Kingdom, Belgium, Germany, Switzerland) completed pre- and post-visit questionnaires about relevance and performance of doctor-patient communication. Data were analyzed by variance analysis and by multilevel analysis. In the non-gatekeeping countries, patients considered both biomedical and psychosocial communication aspects to be more important than the patients in the gatekeeping countries. Similarly, in the patients' perception, the non-gatekeeping GPs dealt with these aspects more often. Patient characteristics (gender, age, education, psychosocial problems, bad health, depressive feelings, GPs' assessment of psychosocial background) showed many relationships. Of the GP characteristics, only the GPs' psychosocial diagnosis was associated with patient-reported psychosocial relevance and performance. Talking about biomedical issues was more important for the patients than talking about psychosocial issues, unless the patients presented psychosocial problems to the GP. Discrepancies between relevance and performance were apparent, especially with respect to biomedical aspects. The implications for health policy and for general practitioners are discussed.

Adolescent↗

Depression influences the EDI scores in anorexia nervosa patients.

AIM: To study the influence of the severity of depression on the eating disorder's inventory (EDI) scores in anorexia nervosa (AN) patients. METHOD: We compared by variance analysis the EDI scores from three groups of AN patients: 55 patients having a major depression (as assessed by a Beck's depression inventory (BDI) >/= 16); 77 patients having a less severe depression (BDI < 16); 32 patients with mild or non-existent depression (BDI </= 7) and the EDI scores from a control group of 29 French healthy young women. RESULTS: Higher EDI scores were elicited in the more severely depressed AN patients than in the less- or non-depressed AN patients (P < 0.01). In non-depressed AN patients, none of the scores was different from those of the control group. This was particularly true for the scores "Slimness wish", "bulimia", "body image dissatisfaction", "perfectionism" and "fear of maturity". The non-depressed restrictive AN patients had no score which differ from healthy controls. DISCUSSION: The present results suggested that the EDI scores are clearly influenced by the severity of depression. Among the psychopathological and behavioural traits assessed with the EDI, only a few were not related to depressive symptoms: "feeling of inefficiency" and "distrust in interpersonal relations".

Adult↗

Determination of the van der Waals, electron donor and electron acceptor surface tension components of static Gram-positive microbial biofilms.

A large number of studies have shown the influence of the physico-chemical properties of a surface on microbial adhesion phenomenon. In this study, we considered that the presence of a bacterial biofilm may be regarded as a "conditioning film" that may modify the physico-chemical characteristics of the support, and thus the adhesion capability of planktonic micro-organisms coming into contact with this substratum. In this context, we adapted a protocol for biofilm formation that allows, under our experimental conditions, contact angle measurements, the reference method to determine the energetic surface properties of a substratum. This made it possible to determine the van der Waals, electron acceptor and electron donor properties of static biofilms grown at 25 degrees C on stainless-steel slides with six Gram-positive bacteria isolated in dairy plants. A variance analysis indicated significant effects (P<0.05) of the bacterial strains and of the physiological state of the micro-organisms (planktonic or sessile) on the contact angles. To link the energetic properties of the six biofilms with direct adhesion experiments, we measured the affinity of fluorescent carboxylate-modified polystyrene beads for the different biofilm surfaces. The results correlated best with the electron-acceptor components of the biofilm surface energies, stressing the importance of Lewis acid-base interactions in adhesion mechanisms.

Journal Article↗

Technique to reduce air leaks after pulmonary lobectomy.

OBJECTIVE: Patients undergoing pulmonary resections often present postoperative air leaks of varying magnitude and duration; this complication is more frequent with incomplete or absent interlobar fissures. Small leaks close spontaneously within 5-7 days; larger leaks may persist longer and could be associated with increased morbidity and prolonged hospitalization. We evaluated the role of different techniques to complete interlobar fissures before pulmonary lobectomy to prevent postoperative air leaks and reduce hospital stay and costs. METHODS: A total of 30 patients undergoing pulmonary lobectomy for lung cancer and presenting incomplete interlobar fissures that needed to be opened both anteriorly and posteriorly were randomized into three groups. In Group I, fissures were created with a GIA stapler and buttressed with bovine pericardial sleeves. In Group II, we used TA 55 staplers alone; in Group III we used the 'old fashion' cautery, clamps and silk ties. The three groups were homogeneous for age, type of pulmonary resection and stage of the tumor. The duration of postoperative air leaks and hospital stay were compared with the one-way variance analysis. RESULTS: Postoperative air leaks for Groups I, II and III persisted for 2 +/- 0.94, 5.3 +/- 2 and 5.3 +/- 1.7 days, respectively. Mean hospital stay was 4.4 +/- 0.96, 7.8 +/- 2.14 and 7.2 +/- 1.5, respectively. The difference between groups in terms of duration of postoperative air leaks and hospital stay was statistically significant (P = 0.0001). CONCLUSIONS: The use of GIA staplers and pericardial sleeves to complete interlobar fissures for pulmonary lobectomy significantly reduces the duration of postoperative air leaks and hospital stay; no complications were associated with this technique.

Aged↗

The inheritance of plasma and red blood cell magnesium and zinc levels studied from twin and family data.

The variability of magnesium and zinc concentrations in plasma and erythrocytes was investigated by twin and family studies. Twins were sampled in two distinct ways and in two different West-European regions. In one of the samples, a distinction was made between twins liver together and twins living apart. Two series of families were studied, one in a homogeneous environment, the other in a more diverse environment. Samples were compared by variance analysis. The results show 1) that genetic variability is significant for red blood cell (RBC) magnesium and zinc, minor for plasma magnesium and absent for plasma zinc; 2) that the family environment affects the extent of resemblance between twins and between siblings more for plasma levels than for RBC levels of magnesium and zinc. Furthermore, the intercorrelation analysis suggests that the genetic regulation systems of RBC magnesium and zinc are different, whereas some of the environmental regulation systems of plasma magnesium and zinc are the same. Biological interpretations are brought forward and discussed.

Adolescent↗

Effects of rapid tryptophan depletion in patients with seasonal affective disorder in natural summer remission.

BACKGROUND: Serotonergic mechanisms have been proposed for the pathophysiology of seasonal affective disorder (SAD) and the therapeutic effect of bright-light treatment. Previously, we showed that SAD patients, in clinical remission with light therapy during the winter, experienced transient depressive relapses after a rapid tryptophan depletion (RTD) technique, which results in decreased brain serotonin levels. The objective of this study was to investigate the effect of RTD in SAD patients who were in natural summer remission. METHODS: Twelve drug-free patients with SAD by DSM-IV criteria and 10 normal subjects participated in this double-blind, placebo-controlled, crossover study. SAD patients were in natural summer remission for at least 8 weeks. Behavioural ratings and plasma tryptophan levels were obtained before, and 5 h after, ingesting an amino acid (AA) mixture +/- tryptophan. Experimental RTD and control sessions were scheduled 1 week apart. RESULTS: The RTD session resulted in significant reduction in total and free plasma tryptophan levels compared to the control session. The behavioural data were analysed using repeated measures analysis of variance. This analysis found significant main effects of time (higher scores after AA ingestion) and diagnosis (higher scores in SAD patients), but no main effect of session or significant interaction effects between the three factors. Thus, there were no significant behavioural effects of RTD compared to the sham depletion control session. CONCLUSIONS: The summer remission experienced by SAD patients is not dependent on plasma tryptophan levels (and presumably brain serotonin function) in the same manner as that of remission after light therapy. These results conflict with those of other laboratories, perhaps because of differences in study samples.

Adult↗

The decade 1989-1998 in Spanish psychology: an analysis of research in statistics, methodology, and psychometric theory.

This paper presents an analysis of research published in the decade 1989-1998 by Spanish faculty members in the areas of statistical methods, research methodology, and psychometric theory. Database search and direct correspondence with faculty members in Departments of Methodology across Spain rendered a list of 193 papers published in these broad areas by 82 faculty members. These and other faculty members had actually published 931 papers over the decade of analysis, but 738 of them addressed topics not appropriate for description in this report. Classification and analysis of these 193 papers revealed topics that have attracted the most interest (psychophysics, item response theory, analysis of variance, sequential analysis, and meta-analysis) as well as other topics that have received less attention (scaling, factor analysis, time series, and structural models). A significant number of papers also dealt with various methodological issues (software, algorithms, instrumentation, and techniques). A substantial part of this report is devoted to describing the issues addressed across these 193 papers--most of which are written in the Spanish language and published in Spanish journals--and some representative references are given.

Bibliometrics↗

NMR approach to the quantification of nonstatistical 13C distribution in natural products: vanillin.

Quantitative (13)C NMR conditions have been established that permit the precise determination of site-specific (13)C/(12)C ratios at low or natural abundance. Spectral acquisition parameters have been optimized in order to obtain minimum intensity distortions over the spectral width and in relation to the major sources of inaccuracy: the relaxation times, the decoupling pulse and power, and nuclear Overhauser effects. A major reduction in experimental time resulting from a study of the relaxation times and variance analysis has been achieved. The influence of (1)H decoupling conditions on peak areas was shown to be critical in that different relative peak areas are obtained according to the decoupling power. The efficiency with which the quantitative (13)C NMR method can determine site-specific (13)C/(12)C ratios in natural products has been tested for 12 independent samples of vanillin from different sources. Discriminatory analysis performed in the space defined by the site-specific carbon isotope ratios allows natural vanillin and that from different synthetic origins to be unambiguously distinguished.

Benzaldehydes↗

Study and mathematical modeling of the production of propionic acid by Propionibacterium acidipropionici immobilized in a stirred tank fermentor.

A mathematical model was developed that describes production of propionic acid by fermentation of sweet whey with Propionibacterium acidipropionici immobilized in calcium polygalacturonate beads in a fermentor-type stirred tank. This mathematical model is constituted by a partial differential equations system, which fits consumption, production, growth and internal diffusion rates in the support. Fermentation was experimentally studied with free cells and immobilized cells, effective diffusivities of lactose and propionic acid were estimated in the support, and typical parameters of the model were obtained by nonlinear regression of the experimental data. The variance analysis shows that the combination of micro(max) and K(d) parameters is the source of variation most significative, also they were found to be the most sensitive parameters of the model. Finally, an effectiveness factor was calculated in order to assess the effect of mass transfer on the overall reaction rate observed.

Cell Division↗

Changes in the polyphenolic and volatile contents of "fino" sherry wine exposed to ultraviolet and visible radiation during storage.

Experiments of accelerated oxidation of "fino" sherry wines have been conducted at 25 degrees C and under the influence of UV-visible radiation (a xenon lamp of 1500 W). With the aim of determining the contribution of UV-vis radiation to the browning phenomenon, two types of glass bottles were employed: topaz bottles (with low values of transmittance in the UV-visible range) and transparent bottles. To identify significant differences between the wine before and after being subjected to the influence of the UV-vis radiation, the values of absorbance at 420 nm and the concentrations of various polyphenolic and volatile compounds were submitted to a multivariate variance analysis. Both factors considered (time and type of bottle) had a statistically significant effect on the values of absorbance at 420 nm and on the concentration of most of the polyphenolic compounds, whereas only the "time" factor was significant for volatile compounds. All wines showed losses in several polyphenolic compounds, which were more severe for the wines bottled in transparent glasses. However, these wines exhibited a lower degree of visual browning (abs 420 nm). In the case of volatile compounds, most of these presented increases during storage exposed to the influence of the UV-vis radiation.

Alcohols↗

Off-vine grape drying effect on volatile compounds and aromatic series in must from Pedro Ximénez grape variety.

Changes in 36 volatile compounds of must from ripe grapes dried by direct exposure to sun and must from ripe grapes were studied. Compounds not dependent on sampling site in both musts were selected, and their concentration/Brix degree ratio values, were subjected to variance analysis. Only butan-1-ol and isoamyl alcohols showed no differences, while (E)-hex-3-en-1-ol, (Z)-hex-3-en-1-ol, (E)-hex-2-en-1-ol, (E)-hex-2-enal, hexanoic acid, isobutanol, benzyl alcohol, 2-phenylethanol, gamma-butyrolactone, gamma-hexalactone, and 5-methylfurfural, showed significant differences between the two must types, which may be ascribed to the drying process. An approach to describe must odor has been carried out by grouping volatile compounds in aromatic series, increasing their values in the fruity, solvent, sweet, and roasted series and diminishing the herbaceous as a consequence of the drying process.

Desiccation↗

Investigation of volatiles in Charentais cantaloupe melons (Cucumis melo Var. cantalupensis). Characterization of aroma constituents in some cultivars.

Volatile compounds of 15 Charentais melon cultivars, known to exhibit differences in their ripening behaviors and in their storage lives (wild, mid, and long shelf life), were investigated. Twenty-eight volatiles (11 esters, 8 sulfur compounds, 6 alcohols, and 3 carbonyl compounds) were isolated by direct dichloromethane extraction and analyzed by means of GC-MS and GC-FID. A considerable reduction in the aroma profile was observed for the long shelf life cultivars, in which total volatiles were 49-87% lower than in the wild or mid shelf life melons. Most of the esters such as ethyl 2-methylbutyrate, ethyl butyrate, ethyl hexanoate, hexyl acetate, and butyl acetate and sulfur compounds such as ethyl 2-(methylthio)acetate, 2-methylthioethanol, ethyl 3-(methylthio)propanoate, 3-(methylthio)propyl acetate, and 3-(methylthio)propanol with low odor values were 2-30-fold lower in long shelf life cultivars than in the others. Discrimination of long shelf life cultivars from wild and mid shelf life melons was achieved by statistical treatment of the data by principal component and variance analysis.

Alcohols↗

Immunohistochemical expression of internal and external ErbB-2 domains in invasive breast cancer.

We tested three ErbB-2 monoclonal antibodies (MoAbs) specific to the intracytoplasmic internal domain (clone CB 11) and the extracellular glycosylated peptide domain (clones CBE1 and Tab250) in 351 primary invasive breast carcinomas. ErbB-2 immunodetection allowed us to differentiate three main groups: group 1 (62.7%) lacked both MoAb ErbB-2 domains (erb -/-); group 2 stained for both domains (erb +/+) (26.5%); group 3 stained for the internal domain only (erb +/-) (10.8%). The relationships among these groups and nodal status (N) were statistically significant, with N+ cases reaching the highest value (89.2%) in the erb +/- group. Lack of immunostaining in the external domain thus seems to be associated with increased metastatic spread. At variance analysis the difference in hormonal receptor content between groups 1 and 3 was not significant; while between groups 1 and 2 it was. The growth fraction of groups 2 and 3 was significantly higher than that of group 1. Our results showed that anti-ErbB-2 MoAb clone CB 11 was able to detect a higher number of ErbB-2 expressing cases than the two that are specific for the external domain (clones Tab 250 and CBE1). Due to the strong association between group 3 cases and the highest metastatic potential, this aggressive group could be identified only with the use of an internal-domain specific MoAb CB 11, which thus seems to present a better discriminative power as a diagnostic marker in the biopathological characterization of breast carcinoma.

Adult↗

Monte Carlo sensitivity analysis of unknown parameters in hazardous materials transportation risk assessment.

The US Department of Transportation was interested in the risks associated with transporting Hydrazine in tanks with and without relief devices. Hydrazine is both highly toxic and flammable, as well as corrosive. Consequently, there was a conflict as to whether a relief device should be used or not. Data were not available on the impact of relief devices on release probabilities or the impact of Hydrazine on the likelihood of fires and explosions. In this paper, a Monte Carlo sensitivity analysis of the unknown parameters was used to assess the risks associated with highway transport of Hydrazine. To help determine whether or not relief devices should be used, fault trees and event trees were used to model the sequences of events that could lead to adverse consequences during transport of Hydrazine. The event probabilities in the event trees were derived as functions of the parameters whose effects were not known. The impacts of these parameters on the risk of toxic exposures, fires, and explosions were analyzed through a Monte Carlo sensitivity analysis and analyzed statistically through an analysis of variance. The analysis allowed the determination of which of the unknown parameters had a significant impact on the risks. It also provided the necessary support to a critical transportation decision even though the values of several key parameters were not known.

Hazardous Substances↗

Histological aspects in bone regeneration of an association with porous hydroxyapatite and bone marrow cells.

The osteogenic potential of an association of two kinds of hydroxyapatite (HA) porous ceramics with autologous bone marrow cells cultured with or without dexamethasone (10(-8)M) addition in the culture medium and non-cultured rabbit marrow stromal stem cells (MSCs) was tested after 4 weeks of implantation in the dorsal muscles of spine in rabbit. A significantly higher number of rabbits with implants containing bone tissue inside pores were obtained with 10(7) cells ml(-1) cultured treated with Dex. In the HA porous ceramic using naphtalen as porogen agent, the bone recolonization remains only at the periphery of implants and in the second row of pores, while in the HA porous ceramic using polymethacrylate (PMMA) microbeads as porogen agent, the bone recolonization is observed in the depth of implants. In the PMMA HA group, the Krüskal-Wallis variance analysis between the rabbits is significantly different with the percentage of number of occupied pores and occupied pores with bone tissue is different (p<0.05).

Journal Article↗

Investigating sources of response variability and neural mediation in human nasal irritation.

A major component of indoor air complaints is nasal irritation (NI), yet there is an extreme paucity of quantitative concentration-response data from normosmics (individuals who report normal odor sensation). Due to an assumption that NI is mediated solely by the activation of the trigeminal (fifth cranial) nerve, much of the small amount of available information has been obtained from anosmic individuals, who lack olfactory (first cranial) nerve input to the brain and, thus, only have nasal trigeminal input remaining. In a repeated measurements design, the NI responses of 31 normosmic and four anosmic individuals were quantified in response to a range of concentrations of propionic acid generated by an automated air-dilution olfactometer. A variance analysis approach was used to apportion different nested sources of variation (within-session, within-individual, inter-individual) in NI responses. In contrast to anosmic NI and normosmic odor performance, NI response by normosmics exhibited considerable variation at all three levels. However, this variation did not obscure the observation that, in agreement with electrocortical measurements by Hummel et al. (1996), NI sensitivity in normosmics clearly exceeded that of anosmics. These observations provide support for enhanced research efforts to better understand the neural basis of NI so that its occurrence in actual environments may be effectively minimized.

Adult↗

Alterations in DNA methylation are early, but not initial, events in ovarian tumorigenesis.

We compared global levels of DNA methylation as well as methylation of a specific locus (MyoD1) in ovarian cystadenomas, ovarian tumours of low malignant potential (LMP) and ovarian carcinomas to investigate the association between changes in DNA methylation and ovarian tumour development. As we realized that cystadenomas showed different methylation patterns from both LMP tumours and carcinomas, we verified their monoclonal origin as a means of confirming their true neoplastic nature. High-pressure liquid chromatographic (HPLC) analyses showed that global methylation levels in LMP tumours and carcinomas were 21% and 25% lower than in cystadenomas respectively (P = 0.0001 by one-way variance analysis). Changes in the methylation status of the MyoD1 locus were not seen in any of ten cystadenomas analysed but were present in five of ten LMP tumours and in five of ten carcinomas (P = 0.03). These findings suggest that alterations in DNA methylation are absent (or at least not as extensive) in ovarian cystadenomas, but are present in LMP tumours, the phenotypic features of which are intermediate between those of benign and malignant ovarian tumours. The results also emphasize the merit of distinguishing ovarian LMP tumours from cystadenomas, in spite of their similar clinical characteristics.

Blotting, Southern↗

Nutritional status of HIV-seropositive subjects in an AIDS clinic in Paris.

OBJECTIVE: To measure the prevalence and analyse the characteristics of malnutrition among subjects attending an AIDS outpatient clinic and a day care center, to improve the nutritional management of HIV-infected subjects. DESIGN: Prospective cross-sectional study. SETTING: AIDS clinic in a University Hospital in Paris. SUBJECTS: 124 HIV-seropositive adults attending the clinic. MAIN OUTCOME MEASURES: Evaluation of nutritional status using anthropometry, impedancemetry, plasma albumin and pre-albumin assays. Degree of malnutrition, defined by the percentage of body weight loss (BWL), calculated by reference to the usual body weight. RESULTS: Among the 124 subjects recruited (M:F sex ratio: 3.3, mean age: 36.3 +/- 7.2 y), 77 (62.1%, 95%CI: 53.9-70.3) had normal nutrition status (BWL < or = 5%), 16 (12.9%, 95%CI: 7.0-18.2) moderate malnutrition (5% < BWL < or = 10%), 21 (16.9% 95%CI: 10.3-23.5) intermediate malnutrition (10% < BWL < or = 20%), and 10 (8.1%, 95%CI: 3.3-12.9) severe malnutrition (BWL > 20%). BWL was related to the CDC class (variance analysis, P < 9 x 10(-5)) and CD4 cell count (P < 3 x 10(-5)). Malnutrition was observed even among CDC class A subjects (14.9%). BWL was also related to the body mass index (P < 3 x 10(-6)), lean body mass (P < 3 x 10(-5)), body fat (P < 7 x 10(-6)), and as assessed by impedancemetry, body cell mass (P < 10(-5)) an the extra/intra cellular water ratio (P < 2 x 10(-4)). The decrease in lean body mass was related to the decrease in body cell mass. CONCLUSIONS: Given its high frequency, malnutrition should be prevented, detected, monitored and treated from the early stages of HIV infection among patients attending AIDS clinics in order to improve survival and quality of life.

Acquired Immunodeficiency Syndrome↗