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PubMedDate not supplied

Wandering in the dark: women's experiences with depression.

In North America, rates of depression for women are consistently higher than for men. This phenomenon is poorly understood; nonetheless, the use of grounded theory to investigate women's experiences with depression, treatment, and recovery revealed some unexpected findings. In this article I discuss findings resulting from examination of data from three grounded theory studies of women and depression. In all, data were collected through participant observation and more than 70 interviews and the study sample included participants varying in race, marital status, cultural background, and sexual orientation between 18 to 69 years of age, and included both mothers and nonmothers. Findings included the presence in women of an internal dialogue, reinforcing the philosophical origins of the method in symbolic interactionism; oppression and marginalization of women's experiences; the impact of violence in women's lives; the roles of treatment and learning; and the hope of recovery. I will finish by identifying some questions arising from the findings.

Adaptation, Psychological↗
PubMed2003

Determination of cholesterol absorption in humans: from radiolabel to stable isotope studies.

Hypercholesterolemia is a major health risk. Dietary cholesterol absorption is one important factor affecting levels of plasma and tissue cholesterol. Considerable effort has thus been devoted to develop reliable in vivo clinical methodologies to determine dietary cholesterol absorption in humans. The present paper summarises radiolabelled experiments and major advances in stable isotope technologies to determine cholesterol absorption. Initially, direct methods employing gastro-intestinal intubation were developed. Later, indirect methods using oral-faecal cholesterol balance permitted calculation of cholesterol mass absorption. Once the use of radiolabelled [3H, 14C]cholesterol balance was developed in healthy humans, it was finally possible to distinguish exogenous and endogenous cholesterol. Non-invasive and safer stable isotope (2H, 13C, 18O) labelled cholesterol tracers then replaced radioisotopes for use in infants and adults. Stable isotopes and radioisotopes showed identical cholesterol kinetics. The most promising contemporary stable isotope assessment of cholesterol absorption is a dual stable isotope dual tracer approach based on simultaneous administration of oral and intravenous differentially labelled cholesterol tracers, followed by plasma sampling for 3-4 d. Online GC/Combustion/IRMS and GC/Pyrolysis/IRMS allow minimal amounts of dual stable isotope cholesterol tracers to be detected. Using the dual stable isotope dual tracer approach, the percent cholesterol absorption in adult volunteers has been determined to be 50-70%.

Absorption↗
PubMed2005

Medial surface dynamics of an in vivo canine vocal fold during phonation.

Quantitative measurement of the medial surface dynamics of the vocal folds is important for understanding how sound is generated within the larynx. Building upon previous excised hemilarynx studies, the present study extended the hemilarynx methodology to the in vivo canine larynx. Through use of an in vivo model, the medial surface dynamics of the vocal fold were examined as a function of active thyroarytenoid muscle contraction. Data were collected using high-speed digital imaging at a sampling frequency of 2000 Hz, and a spatial resolution of 1024 x 1024 pixels. Chest-like and fry-like vibrations were observed, but could not be distinguished based on the input stimulation current to the recurrent laryngeal nerve. The subglottal pressure did distinguish the registers, as did an estimate of the thyroarytenoid muscle activity. Upon quantification of the three-dimensional motion, the method of Empirical Eigenfunctions was used to extract the underlying modes of vibration, and to investigate mechanisms of sustained oscillation. Results were compared with previous findings from excised larynx experiments and theoretical models.

Animals↗
PubMed1991

Daily illness characteristics and health care decisions of older people.

Although investigations of health care decision making typically deal with patterns of health service use, increasing attention has focused on lay- and self-care actions in response to illness symptoms. This study examined the health care actions of a community sample of 142 older adults, who recorded illness symptoms and corresponding health care actions in daily health diaries for a 14-day period. Self-treatment and no-action decisions were found to be the most frequent response to illness symptoms. Professional-care decisions were associated with greater health care need, such as multiple symptoms and increased pain. Lay-care decisions were significantly related to symptoms of shorter duration. Women were also more likely than men to self-treat their illness symptoms. Results suggest that older people deal with a greater number of recurrent chronic symptoms than previously thought and that they make most treatment decisions without consulting their doctors or other health care providers. This investigation underscores the importance of a prospective diary methodology for studying the daily complexities of chronic illness experiences and for validating and conducting useful interventions.

Aged↗
PubMed1992

School-aged children's interpretation of their experience with acute surgical pain.

This study examined the intensity of pain children experience following surgical procedures, the relationship between analgesic administration patterns and perceived level of pain, and children's affective, cognitive, and sensory interpretation of their experiences with pain. The sample included 24 children between 7 and 11 years of age who were hospitalized after abdominal, orthopedic, or urologic surgery. Children rated the intensity of their pain on a visual analog scale three times on the day after surgery. A chart review examined analgesic administration. On the third day after surgery, children were interviewed about their experiences with pain. The findings provide insight into the content of children's fears and concerns when they have postoperative pain, and how they interpret their responses and the responses of others in the management of their pain experience.

Adaptation, Psychological↗
PubMed2005

Significance analysis of time course microarray experiments.

Characterizing the genome-wide dynamic regulation of gene expression is important and will be of much interest in the future. However, there is currently no established method for identifying differentially expressed genes in a time course study. Here we propose a significance method for analyzing time course microarray studies that can be applied to the typical types of comparisons and sampling schemes. This method is applied to two studies on humans. In one study, genes are identified that show differential expression over time in response to in vivo endotoxin administration. By using our method, 7,409 genes are called significant at a 1% false-discovery rate level, whereas several existing approaches fail to identify any genes. In another study, 417 genes are identified at a 10% false-discovery rate level that show expression changing with age in the kidney cortex. Here it is also shown that as many as 47% of the genes change with age in a manner more complex than simple exponential growth or decay. The methodology proposed here has been implemented in the freely distributed and open-source edge software package.

Adult↗
PubMedDate not supplied

Determination of plasma-free fatty acid kinetics with tracers: methodologic considerations.

Plasma-free fatty acids (FFA) are an important source of energy for a variety of tissues. Recently, there has been an increased interest in the measurement of FFA kinetics in vivo, using radiolabeled or stable isotopic tracers. Standard techniques for measurement of FFA-specific activity are relatively imprecise and have limited sensitivity. We have developed a method for determination of the concentration and specific activity of individual plasma FFA that is precise (coefficient of variation less than 2%) and sensitive (detection limit in the high femptomolar to low picomolar range). Using this method, one can measure the kinetics of three or more long-chain fatty acids simultaneously. Its sensitivity is a particular advantage if one wishes to measure low rates of FFA turnover such as are encountered during hyperinsulinemia. It has been suggested that, for optimal accuracy in the determination of substrate kinetics, the tracer should be administered in the left ventricle and mixed venous blood samples should be obtained from the right heart. We have conducted experiments in dogs which demonstrate that peripheral tracer infusion and more conventional arterial (or arterialized venous) sampling actually provide more accurate estimates of FFA turnover; this is fortunate, since intracardiac infusion and sampling are not practical for human studies.

Animals↗
PubMed2001

Predicting vegetative inoculum performance to maximize phytase production in solid-state fermentation using response surface methodology.

Microbial phytase is used to reduce the environmental loading of phosphorus from animal production facilities. The limiting factors in the use of this enzyme in animal feeds can be overcome by solid-state fermentation (SSF), which is a promising technology for commercial enzyme production with lower production costs. Inoculum quality and the influence of inoculum quality on phytase production are important factors which need in-depth investigation before scaling-up of high-yielding fermentation process. A full factorial experimental design for 240 h with sampling at every 24 h was used to determine the effects of the treatments, inoculum age (plate and liquid culture), media composition and the duration of SSF on the production of fungal biomass and phytase in SSF systems using Aspergillus niger. The optimal treatment combination for maximal phytase production was determined by statistically comparing all treatments at each sampling time. Both 7- and 14-day plate cultures and M1 + medium composition with 72-h-old liquid inoculum treatments resulted in optimal phytase production at 144 h of SSF, which was the shortest duration observed for maximal phytase production. This resulted in maximal phytase production with a mean of 884 +/- 121 U/g substrate, while the maximal phytase production observed at 216 h of SSF (mean phytase activity of 1,008 +/- 121 U/g substrate), with the same treatment combinations, was not statistically significant from that at 144 h of SSF. Phytase production was strongly growth-associated with younger inocula. The significant treatment variables, age of liquid inoculum and the duration of SSF, were used to predict the system response for phytase production using response surface methodology. From the response surface model, the optimal response of the experiment was predicted and the reliability of the prediction was checked with the verification experiment.

6-Phytase↗
PubMedDate not supplied

[Placebos in clinic and research: experimental findings and theoretical concepts].

The placebo response in medicine and psychology is incompletely understood, and is usually either mystified or down-played; a rational approach to the understanding of the placebo response, however, can be deduced from the scientific literature. We present 3 theories that may explain most of the placebo response in medical and psychological interventions: a) Regression to the mean (RTM): This refers to "errors" in measuring the outcome of therapies, that are due to small samples sizes, global assessment variables, spontaneous variability of symptoms, and other methodological reasons. b) Pavlovian Conditioning (PC): here the placebo response occurs as the consequence of successful association of diagnostic and therapeutic procedures in the past (illness history) of the individuum that resulted in symptom improvement. Neutral stimuli in the context of a treatment can thus gain therapeutic potency (become conditioned stimuli), e. g. the procedure of an injection or the colour of a drug. c) Signal detection theory (SDT): manipulation of expectencies and cognitions of the patient by suggestions and verbal instructions of the health care system will change the willingness of the patient to perceive symptoms as improved/worsened, specifically if this happens under "noisy" circumstances, e. g. with high spontaneous variability of symptoms. All three models are illustrated with examples from medical and psychological treatments or experiments, including recent findings of cortical correlates of the placebo response in functional brain imaging investigations. Potential biological mechanisms for the placebo response are discussed, including the possibility of genetic predisposition to be a placebo responder.

Clinical Trials as Topic↗
PubMedDate not supplied

Actigraphy as a measure of physical activity for wheelchair users with spinal cord injury.

BACKGROUND: Research has indicated that actigraphy is valid and reliable for measuring low levels of physical activity among ambulatory individuals, and that it may be a valid indicator of energy expenditure for wheelchair users in laboratory conditions, but there are no reports of its evaluation in free-living conditions. OBJECTIVE: To assess the suitability and validity of actigraphy as a measure of free-living physical activity for wheelchair users with spinal cord injury. METHODS: In a methodologic descriptive correlational study, measures of physical activity by an actigraph and a self-report physical activity record were obtained for six individuals in laboratory conditions and 22 individuals in free-living conditions during a 4-day period. At the completion of the home monitoring trial, all the participants completed a questionnaire about their experience wearing the monitor and maintaining the record. RESULTS: Mean activity counts by actigraphy during active tasks were significantly different from the counts during inactive tasks (p =.003). During home monitoring, the participants wore the monitor, on the average, 95% of the prescribed wearing time, rated it as very comfortable, and were willing to wear it again. Pearson correlation coefficients of activity counts with self-reported activity intensity varied from.30 to.77 (p <.01) for individual participants. The mean correlation across the sample was.60 (p <.01). Activity counts varied with reported activity, indicating concurrence between the two activity measurement methods. CONCLUSIONS: Actigraphy is suitable as a measurement of activity for people with spinal cord injury. This initial investigation suggests that it has concurrent validity with a self-report measure of activity intensity and frequency, as evidenced in this sample of wheelchair users in free-living conditions.

Adult↗
PubMed2004

Using survey data for diabetes surveillance among minority populations: a report of the Centers for Disease Control and Prevention's expert panel meeting.

INTRODUCTION: Data on diabetes morbidity and mortality and the quality of care among U.S. minority populations are necessary to assess progress toward eliminating racial/ethnic disparities and to design and implement effective interventions. This paper summarizes the discussions and recommendations of an expert panel to address the use of survey data for diabetes surveillance among minority populations. METHODS: The Centers for Disease Control and Prevention's Division of Diabetes Translation convened an expert panel of persons with survey experience and awareness of the problems in conducting health-related surveys among minority populations. Panel members were asked to 1) determine ways to enhance the ability of existing survey systems to address diabetes surveillance among minority populations; 2) identify survey systems that could be used to address surveillance needs; and 3) determine whether new minority-specific survey systems need to be developed. RESULTS: Panel members concluded that, although no existing survey system is completely adequate for diabetes surveillance among minority populations, new systems should not be developed. They recommended 1) investigating the use of community-based surveys; 2) exploring the ability of national surveys to increase sample sizes and produce state-level estimates; and 3) encouraging government agencies and public health programs to coordinate and integrate diabetes-related survey data and share analytic methodology. CONCLUSION: No existing survey is suitable for conducting minority-specific diabetes surveillance. Modifying and expanding existing surveys to establish a diabetes surveillance system of sentinel minority populations would be more feasible than developing a new one. Interagency coordination and collaboration will be critical in this effort.

Centers for Disease Control and Prevention, U.S.↗
PubMedDate not supplied

Evaluation of antioxidant properties of dermocosmetic creams by direct electrochemical measurements.

Cyclic voltammetry and linear sweep voltammetry were preliminarily used in order to evaluate the global antioxidant properties of dermocosmetic creams. Experiments were performed by introducing electrodes directly into the creams without any pretreatment of the samples. Current-potential curves showed significant anodic current depending on the antioxidant-containing cream studied. In comparison, little amperometric response was recorded with an antioxidant-free cream base. Aqueous solutions of the corresponding antioxidants showed analogous anodic waves and similar peak potentials. A correlation between the global anodic peak and the presence of the antioxidant species in the cream was made with eleven skin creams, attesting to the reliability of the method. Among the tested electrode materials, platinum gave the best results in terms of electrochemical kinetics and measurement precision (current peak standard deviation less than 5%). Exposure of a depilatory cream to oxidizing agents (e.g., hydrogen peroxide, air, or light) caused a decrease in peak current as expected. This methodology enabled us to evaluate the evolution of the total antioxidant capacity under oxidative stress and gives encouragement to further development of a voltammetric method to quantify cream antioxidant power.

Antioxidants↗
PubMed1998

The surrogate's experience during treatment decision-making.

PURPOSE: To explore the experiences, thoughts, and feelings of surrogates making decisions for older adults. To identify nursing practices perceived as helpful to surrogates. SAMPLE: Eleven surrogate decision-makers. METHOD: Qualitative. Semi-structured interviews/descriptive data used to enrich a larger study. FINDINGS: Four main themes were identified that described the surrogates' experiences: Contextualizing the decision Actualizing agency Reviewing and resolving Transcending CLINICAL IMPLICATIONS: Three paradigm cases describe caregiving, protecting, and trusting response patterns of surrogates. Surrogates found decision-making an evolving and difficult process. Nurses can be more helpful to surrogates by giving them more opportunities to ask questions, solicit information, express emotions and obtain comfort and support.

Aged↗
PubMed2007

Psychosocial registry for persons with cancer: a method of facilitating quality of life and symptom research.

Research focused on the psychosocial aspects of the experience of persons with cancer and their family caregivers is hampered by the methodological challenges inherent in quality of life research. A data registry offers a potential solution to many of these problems in providing a large, comprehensive database, using standardized instruments. We report here our preliminary experience with establishing a Psychosocial Registry designed to advance research in the psychological, social, and spiritual aspects of quality of life of newly diagnosed cancer patients and their family caregivers. The first six months of enrollment demonstrated that the majority of newly diagnosed patients approached for consent (68%) and their primary family caregiver (92%) were willing to participate in the registry; of these, 80% also agreed to be contacted in the future for additional studies. Face-to-face interview was the preferred method of data collection. Our preliminary experience suggests that continuation of the registry with the current modest level of resources would generate a sample of approximately 1000 patients in three years. The long-range goal is to establish a national psychosocial data registry that will enroll patients at diagnosis and follow them through the entire cancer experience, including end of life or survivorship.

Aged↗
PubMed2006

[Placebo response in functional bowel disorders].

The placebo response in functional bowel disorders is incompletely understood, and is usually either mystified or down-played; a rational approach to the understanding of the placebo response, however, can be deduced from the scientific literature. We present 3 theories that may explain most of the placebo response in medical and psychological interventions. a) Regression to the Mean (RTM): This refers to "errors" in measuring the outcome of therapies that are due to small samples sizes, global assessment variables, spontaneous variability of symptoms, and other methodological reasons. b) Pavlovian Conditioning (PC): Here the placebo response occurs as the consequence of successful association of diagnostic and therapeutic procedures in the past (illness history) of the individual that resulted in symptom improvement. Stimuli in the context of a treatment can thus gain therapeutic potency (become conditioned stimuli), e. g., the procedure of an injection or the colour of a drug. c) Signal Detection theory (SDT): Manipulation of expectations and cognitions of the patient by suggestions and verbal instructions of the health-care system will change the willingness of the patient to perceive symptoms as improved/worsened, specifically if this happens under "noisy" circumstances, e. g., with high spontaneous variability of symptoms. All three models are illustrated with examples from the medical and psychological treatments or experiments, including recent findings of cortical correlates of the placebo response in functional brain imaging investigations. Potential biological mechanisms for the placebo response are discussed, including he possibility of the genetic predisposition to be a placebo responder.

Clinical Trials as Topic↗
PubMedDate not supplied

[Appropriateness evaluation of short hospital admissions using Appropriateness Evaluation Protocol (Italian version): experience of a teaching hospital].

Italian version of Appropriateness Evaluation Protocol (AEP) is a tool for evaluating the appropriateness of hospitalization for acute patients. In particular, it aims to verify and quantify the reasons of appropriateness associated to the day of admission and the single days of hospital stay. The aim of the present paper is to evaluate the appropriateness of ordinary, 2-3 days lasting, hospital admissions within an university hospital. We examined a sample of 518 hospital admissions: 370 admissions (71%) lasting 2 days, and 148 admissions (29%) lasting 3 days. Results analysis showed different levels of appropriateness between the 2-days and the 3-days admissions: the appropriate admissions were 18% in the sample of the 2-days admissions and 38% in the sample of 3-days admissions. Most inappropriate days of admission and stay in hospital are due to attended or to the execution of diagnostic procedures. In order to evaluate accuracy by means of AEP methodology, it is necessary to improve the quality of medical documentation using standardized medical records. AEP, in the framework of the continuous quality improvement, is a valid tool to reorganise health care processes.

Diagnosis-Related Groups↗