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PubMed2006

Disease-specific quality of life in Turkish patients after successful kidney transplantation.

To investigate disease-specific quality of life (QOL) in Turkish patients after successful kidney transplantation, the End-Stage Renal Disease Symptom Checklist Transplantation Module (ESRD-SCL-TM), a multidimensional questionnaire measuring disease-specific QOL, was translated and administered to a sample of successfully transplanted patients. Intercultural differences between Turkish and German patients as well as the influence of demographic (age, gender) and clinical (duration of graft function, living versus cadaver transplantation) data in the Turkish patients were evaluated by multivariate analyses of variance, and correlative techniques. The 152 investigated Turkish patients, including 106 (69.7%) men and 46 (30.3%) women, had a mean age of 34.8 years (SD = 10.8, range, 14 to 67 years). Time since successful kidney transplantation varied between 1 and 297 months (mean = 19.2 months; SD = 36.9). One hundred twelve patients (73.7%) received a kidney from a living donor, and 40 (26.3%) from a cadaver. The Turkish patients suffered statistically significantly more from disease-specific distress than the German patients (19% explanation of variance). They reported higher distress regarding four of six subscales. Turkish women suffered statistically significantly more from "Limited Physical Capacity," and "Side-effects of Corticosteroids" (10% explanation of variance) than men. The demonstrated higher disease-specific distress in successfully transplanted Turkish patients compared to the German samples may be the result of intercultural differences in reporting psychological and disease-specific distress. On the other hand, the higher distress of women compared to men is well known. Both results pointed out the necessity of psychological support.

Cognition↗

PubMed1999

Exogenous corticosteroid exposures are associated with increased recollection of traumatic life events.

BACKGROUND: Exogenous corticosteroid exposures are associated with depression in clinical samples, however, the mechanisms underlying this association are unknown. Recent animal studies have shown that corticosteroids enhance conditioning in stressful learning paradigms. It has been hypothesized that corticosteroids may enhance the recollection of stressful experiences in humans, potentially contributing to the etiology of corticosteroid induced depression. This hypothesis has not been evaluated in human subjects. METHODS: The first phase of the Canadian National Population Health Survey collected data from a probability sample of 17626 members of the general Canadian population over the age of 12. The data set included measures of drug exposure (including corticosteroid exposures) and childhood and adult psychosocial stressors, including traumatic life events. In this study, self-reported traumatic life events were cross-tabulated against corticosteroid exposures in order to evaluate whether these variables were associated. RESULTS: 52% of subjects treated with corticosteroids in the month prior to the interview, as compared to 41% of non-exposed subjects reported one or more of the following stressors: parental divorce, long term parental unemployment, a "frightening" event that was "thought about for years after", being sent away from home for doing something wrong, parental drug or alcohol abuse, or physical abuse. This difference was statistically significant at the 5% level of confidence. LIMITATIONS: The use of cross-sectional survey data in this study precluded confirmation that changes in the pattern of trauma recollection followed exposure to corticosteroids. Also, the study relied on unconfirmed self reported medication exposure data, and ratings from brief survey instruments concerned with life events, stress levels and traumatic experiences. CONCLUSIONS: What we report is consistent with, but not confirmatory of, the hypothesis that increased recollection of stressful events may be a mechanism underlying associations between corticosteroids and depression. Additional research is needed in order to determine whether the basis for this association is an altered recollection of life events, or in a differing pattern of life experiences.

Adolescent↗

PubMed1993

Scorpion envenomation in eastern Saudi Arabia.

STUDY OBJECTIVE: To prospectively collect data on the initial presentation of victims of scorpion envenomation during the deployment of US forces to Saudi Arabia in support of Operation Desert Shield. DESIGN: A four-month prospective analysis of the circumstances, initial clinical signs and symptoms, treatment rendered, and subsequent clinical course of patients suffering scorpion envenomation. Data were analyzed using descriptive statistics. Scorpions were identified from physical remains. SETTING: Open desert in eastern Saudi Arabia 250 miles northeast of Riyadh. Ten battalion aid stations supporting a US armored cavalry division provided first-echelon medical care to 7,000 soldiers. TYPE OF PARTICIPANTS: The 40 male and three female patients were American military personnel between 19 and 33 years old. INTERVENTION: The constraints of military action precluded an interventional protocol. Each medical officer rendered appropriate medical care according to experience. MEASUREMENT AND MAIN RESULTS: During 118 days of encampment, 57 cases were reported, with 43 containing sufficient data for inclusion in the study. Thirty-six (63%) cases occurred during six weeks of initial fortification activity in open desert. Thirty-five victims (79%) presented for medical care within one hour after envenomation. The most common local symptoms and signs were pain (100%) and erythema (63%). The prevalent systemic symptom was apprehension (44%), with tachycardia (72%) and hypertension (58%) the prevalent systemic signs. With one exception, neurologic and cardiorespiratory complications were transient and responded well to fluid support and low doses of beta-sympathomimetics, parasympathetic antagonists, H1 blockers, and analgesics. CONCLUSION: The local and systemic response by victims in this study are consistent with previously documented cases of scorpion envenomation. In adult patients without serious prior adverse medical conditions, intervention is best limited to supportive measures.

Adrenergic beta-Agonists↗

PubMed2006

Sex differences in prenatal oral-motor function and development.

The aim of this study was to investigate sex-related differences in the prenatal development of early oral, lingual, pharyngeal, and laryngeal motor activities. Sonographic images of oral-upper airway regions were observed in 85 healthy fetuses (43 males, 42 females; mean gestational age 24wks 3d [SD 0.69]; range 15-38wks). Biometric data on morphologic development and associated motor patterns were compared across second and third trimesters. Results showed that while males and females demonstrated statistically similar patterns of general physical growth (p>0.05), significant differences in development of specific lingual and pharyngeal structures were present (p<0.05). Significant differences were found for laryngeal and pharyngeal motor activity, and oral-lingual movements (p<0.05). Complex oral-motor and upper airway skills emerged earlier in females, suggesting a sex-specific trajectory of motor development. It was concluded that differential patterns of prenatal motor development may be important in defining sex-specific indices of oral skill maturation.

Female↗

PubMed2006

Gelatin hydrogels cross-linked with bisvinyl sulfonemethyl. 2. The physical and chemical networks.

This paper deals with the physical and the chemical gelation of gelatin in the presence of a reactant, bisvinyl sulfonemethyl (BVSM). The strategy of this investigation is to separate the contributions of the two types of cross-links in order to deduce the resultant elasticity of the network. In addition, the question raised by several authors concerning an increase of the thermal stability of the triple helices in the presence of cross-links was examined by using several techniques. In this study, the concentration of gelatin and BVSM were kept constant, while the influence of the thermal protocols was put in evidence. The gel formation was followed by rheological, thermodynamic (microcalorimetry), and optical spectroscopy (optical rotation) measurements. The results demonstrate the large differences which arise on the storage moduli by changing the thermal protocols. Cross-linking of the networks in the presence of the triple helices induce a heterogeneous repartition of the bonds, which can form along the triple helices and at the end of the sequences. Consequently, the rubber like network obtained by denaturation of the triple helices is still reminiscent of the initial twist of the chains, and a large modulus is observed, as if rigid segments were still present (storage modulus 10 times larger than for random cross-linking). The hydrogels have an elastic modulus which is larger that the addition of the physical and chemical contributions. The interpretation of the network elasticity is based on the predominant role of the rigid rods of triple helices, where the BVSM cross-links can either modify the ratio between the apparent length and distance between rods, l/d, and/or increase the rigidity of the interchain connections, which are loose coils for the physical gels. The hydrogels investigated have a network which is still close to the percolation threshold of the physical gel, and therefore, the statistical models known for well developed networks cannot be directly validated in these experimental conditions.

Journal Article↗

PubMed2004

Health and happiness in young Swiss adults.

PURPOSE: To explore whether self-reported happiness is associated with mental and physical health status among young adults. METHODS: Cross-sectional survey of 1257 randomly selected university students in Geneva, Switzerland. The questionnaire included an item that probed the feeling of happiness in the past month, the Short Form-12 health survey (from which mental and physical health scores were computed), scales to measure self-esteem, stress, and social support, reports of various life problems, and sociodemographic information. RESULTS: Most participants felt happy all of the time or most of the time (63%). In multivariate analysis, feeling happy all or most of the time was strongly associated with better mental health (odds ratios for consecutive quartiles of mental health scores: 1.0 (reference), 6.8 (95% confidence interval (CI): 4.5-10.1), 19.2 (95% CI: 12.2-30.2), 39.9 (95% CI: 22.4-71.0)), but also with the feeling of getting enough love and affection (item from the social support scale, odds ratio: 1.9; 95% CI: 1.4-2.7), female sex (odds ratio: 1.5; 95% CI: 1.1-2.1), being Swiss (odds ratio: 1.8; 95% CI: 1.3-2.5), and higher self-esteem (odds ratios for consecutive quartiles ranged from 1.0 to 3.5, 95% CI: 2.1-5.8). The association between happiness and physical health was weak and statistically non-significant. CONCLUSIONS: The strong association between happiness and mental health suggests that asking people if they are happy may help identify mental health care needs. Self-reported happiness may also be a useful outcome measure for evaluation of health interventions.

Adult↗

PubMed2000

Experimental test of quantum nonlocality in three-photon Greenberger-Horne-Zeilinger entanglement

Bell's theorem states that certain statistical correlations predicted by quantum physics for measurements on two-particle systems cannot be understood within a realistic picture based on local properties of each individual particle-even if the two particles are separated by large distances. Einstein, Podolsky and Rosen first recognized the fundamental significance of these quantum correlations (termed 'entanglement' by Schrodinger) and the two-particle quantum predictions have found ever-increasing experimental support. A more striking conflict between quantum mechanical and local realistic predictions (for perfect correlations) has been discovered; but experimental verification has been difficult, as it requires entanglement between at least three particles. Here we report experimental confirmation of this conflict, using our recently developed method to observe three-photon entanglement, or 'Greenberger-Horne-Zeilinger' (GHZ) states. The results of three specific experiments, involving measurements of polarization correlations between three photons, lead to predictions for a fourth experiment; quantum physical predictions are mutually contradictory with expectations based on local realism. We find the results of the fourth experiment to be in agreement with the quantum prediction and in striking conflict with local realism.

Journal Article↗

PubMed2002

Care-related risk factors for chronic diabetic complications in developing countries: a case from Egypt.

This work was the second phase of a wider study aiming at defining a plan for the improvement of health care services for diabetic patients and to decrease the incidence of its complications. The aim of this phase of the study was to define preventable risk factors for chronic diabetic complications, especially care-related factors. A total of 472 diabetic patients with chronic complications were compared with 528 control patients, free from complications, in a multicentric case-control study. Multivariate logistic regression analysis revealed that diabetic patients over 49 y of age, and female gender were more likely to develop chronic diabetic complications. Among clinical variables, type and duration of diabetes, glycemic control, and hypertension were significant predictors of diabetic complications. Regarding patient and system practices, non-health-insurance, need of help to reach health care facility, irregularity of follow-up visits and attending more than one clinic for follow-up, sources of health information other than physician and nurse, non-practicing leisure physical activities, and smoking were statistically significant risk factors. The study helped to identify preventable risk factors for serious complications of diabetes. It also identified groups of patients who needed priorities of screening programmes for potential development of complications since they were likely to develop such type of complications.

Case-Control Studies↗

PubMed2004

Interfacial statistical geometry: fluids adsorbed in wedges and at edges.

An exact sum rule is derived that links the structure of fluids adsorbed in wedges and at edges to the interfacial free energy far from the wedge apex. By focusing on hard-wall models, one observes a correspondence between interfacial statistical mechanics and geometry. The physical necessity of this correspondence can be argued from the presence of complete drying at a hard wall. Invoking the potential distribution theorem generates yet another class of geometric results, this time concerning the excluded volume generated by a sphere rolling along the surface of the wedge. Direct proof of these latter geometric theorems is straightforward in two-dimensions. Acute wedges and the right-angled wedge, provide examples of models for which comparison with simulation data and density functional theory are available.

Journal Article↗

PubMed2005

Adaptive resolution molecular-dynamics simulation: changing the degrees of freedom on the fly.

We present a new adaptive resolution technique for efficient particle-based multiscale molecular-dynamics simulations. The presented approach is tailor-made for molecular systems where atomistic resolution is required only in spatially localized domains whereas a lower mesoscopic level of detail is sufficient for the rest of the system. Our method allows an on-the-fly interchange between a given molecule's atomic and coarse-grained levels of description, enabling us to reach large length and time scales while spatially retaining atomistic details of the system. The new approach is tested on a model system of a liquid of tetrahedral molecules. The simulation box is divided into two regions: one containing only atomistically resolved tetrahedral molecules, and the other containing only one-particle coarse-grained spherical molecules. The molecules can freely move between the two regions while changing their level of resolution accordingly. The hybrid and the atomistically resolved systems have the same statistical properties at the same physical conditions.

Journal Article↗

PubMed2005

Statistical signals in bioinformatics.

The Arthur M. Sackler Colloquium of the National Academy of Sciences, "Frontiers in Bioinformatics: Unsolved Problems and Challenges," organized by David Eisenberg, Russ Altman, and myself, was held October 15-17, 2004, to provide a forum for discussing concepts and methods in bioinformatics serving the biological and medical sciences. The deluge of genomic and proteomic data in the last two decades has driven the creation of tools that search and analyze biomolecular sequences and structures. Bioinformatics is highly interdisciplinary, using knowledge from mathematics, statistics, computer science, biology, medicine, physics, chemistry, and engineering.

Animals↗

PubMed2006

Risk factors for overweight among Brazilian adolescents of low-income families: a case-control study.

OBJECTIVE: To study risk factors for overweight among Brazilian adolescents of low-income families. DESIGN: Case-control study of obese and non-obese adolescents. SETTING: Anthropometric survey including 1420 students (aged 14-19 years) attending a public high school in São Paulo, Brazil. METHODS: Selection of 83 overweight (body mass index (BMI) >85th percentile) and 89 non-overweight (BMI >5th percentile and <85th percentile) subjects, frequency-matched by age, gender, pubertal development and socio-economic status. Among the nutritional, familial and behavioural data available, five covariates (parents' obesity, adolescents' past obesity, to have a best friend, dietary restriction and habit of napping) were included in the fitted hierarchical conditional logistic regression models. MEASUREMENTS: Parents or guardians and adolescents were weighed, measured and answered a pre-tested questionnaire applied by trained nutritionists and paediatricians. RESULTS: The prevalence of overweight was 15.2%. As previous risks, obese parents and obesity during infancy presented odds ratios (OR) and 95% confidence intervals (CI) of 2.23 (1.15-4.35) and 3.60 (1.47-8.80), respectively. As concurrent factors, the habit of napping, to have a best friend and reported dietary restriction presented OR (95% CI) of 3.43 (1.32-8.92), 5.15 (1.76-15.07) and 7.26 (2.95-17.88), respectively. Dietary patterns, frequency of obesogenic foods and other physical activity indicators presented no statistical significance. CONCLUSION: In case-control studies, OR may overestimate the true risks. Parents' obesity and previous childhood obesity were identified as risk factors; therefore these factors should be the target for preventive programmes and policies in order to prevent the burden of obesity in the near future.

Adolescent↗

PubMed1998

Background variables (medical history, anthropometric and biological factors) in relation to the outcome of lumbar disc surgery.

In a prospective cohort study 122 patients with herniated intervertebral lumbar disc and no previous low back surgery preoperatively were assessed regarding medical history, anthropometric and biological background variables. The outcome of surgery (traditional methods) was evaluated one year postoperatively, mainly using a composite Clinical Overall Score (COS), including pain intensity, physical signs, functional capacity and analgesics. Return to work was also assessed. In regression analyses, low body height, high values of weight and body mass index, as well as long duration of sickness absence were shown to be significantly related to a poor outcome, as evaluated by the COS. However, after controlling for modifying effects of previously determined predictive fibrinolytic and psychological variables, the background variables lost their significance. Female sex, low stature, long duration of sickness absence and physically strenuous work activities were statistically significantly related to lower frequencies of return to work.

Body Height↗

PubMed1998

Clinical overall score: outcome evaluation after lumbar disc surgery, assessments of reliability and validity.

In previous studies assessing prognostic factors for the outcome of lumbar disc surgery, a Clinical Overall Score (COS) based on four subsets-pain intensity (VAS), physical signs, functional status (Oswestry) and analgesics--was used as the main outcome criterion. Both the patient's and the examiner's opinions of outcome and return to work were registered. In this paper, assessments are made of reliability and validity regarding the COS. The COS was found sensitive to changes, and internal consistency, assessed using Cronbach's alpha, Pearson's correlation analyses and factor analysis, was good. An interrater reliability study of the assessments of the physical signs, using weighted Kappa statistics, demonstrated fair to good levels of agreement for most of the signs. The concurrent validity of the COS was satisfactory; COS compared favourably with the patient's and with the examiner's opinion of outcome and return to work.

Adult↗

PubMed1999

Mathematical models of tumour and normal tissue response.

The historical application of mathematics in the natural sciences and in radiotherapy is compared. The various forms of mathematical models and their limitations are discussed. The Linear Quadratic (LQ) model can be modified to include (i) radiobiological parameter changes that occur during fractionated radiotherapy, (ii) situations such as focal forms of radiotherapy, (iii) normal tissue responses, and (iv) to allow for the process of optimization. The inclusion of a variable cell loss factor in the LQ model repopulation term produces a more flexible clonogenic doubling time, which can simulate the phenomenon of 'accelerated repopulation'. Differential calculus can be applied to the LQ model after elimination of the fraction number integers. The optimum dose per fraction (maximum cell kill relative to a given normal tissue fractionation sensitivity) is then estimated from the clonogen doubling times and the radiosensitivity parameters (or alpha/beta ratios). Economic treatment optimization is described. Tumour volume studies during or following teletherapy are used to optimize brachytherapy. The radiation responses of both individual tumours and tumour populations (by random sampling 'Monte-Carlo' techniques from statistical ranges of radiobiological and physical parameters) can be estimated. Computerized preclinical trials can be used to guide choice of dose fractionation scheduling in clinical trials. The potential impact of gene and other biological therapies on the results of radical radiotherapy are testable. New and experimentally testable hypotheses are generated from limited clinical data by exploratory modelling exercises.

Brachytherapy↗

PubMed1999

Spiritual aspects of loss among partners of men with AIDS: postbereavement follow-up.

This article is a follow-up study of bereaved caregiving male partners of men with AIDS (T.A. Richards & S. Folkman, 1997). The earlier study examined spiritual beliefs, experiences, and practices reported in interviews with 125 caregivers conducted 2 and 4 weeks following bereavement. This follow-up study reports qualitative and quantitative data from 70 members of the earlier cohort, collected 3 to 4 years later, regarding the presence of spiritual phenomena. Spirituality increased or deepened in 77% of the entire cohort. An ongoing relationship with the deceased partner was reported by 70% of the cohort. The use of spirituality as coping appeared to decline as the bereaved moved further in time from the loss. Instead, spirituality was identified as a personal governing influence that provided value and direction to the individual. In general, relationships between the expression of spirituality and mood, coping, and physical health symptoms were not statistically significant owing to small samples, but there were medium effect sizes.

Acquired Immunodeficiency Syndrome↗

PubMed1984

Ethnic status and participation in longitudinal health surveys.

Ethnic differences in survey participation and their effects on self-reported physical and psychiatric health status measures were examined in a longitudinal health study in Alameda County, California, in 1978 following two time intervals. Blacks and Mexican-Americans were more likely than whites to refuse to participate in follow-up surveys and were more difficult to trace when the time interval between interviews was long. With the exception of age, demographic characteristics were not consistently associated with participation status either across ethnic groups or across time periods. Self-reported psychiatric and physical health status were not statistically associated with participation status in any ethnic group for either time period, despite differential participation by ethnicity.

Adult↗

PubMedDate not supplied

A relaxation response randomized trial on patients with chronic heart failure.

PURPOSE: Patients with various medical conditions benefit from eliciting the relaxation response (RR), using a variety of techniques, but few studies have focused on chronic heart failure (CHF). We evaluated the efficacy of an RR intervention program on the quality of life (QOL) and exercise capacity of CHF patients by conducting a single-blind, 3-arm, randomized, controlled trial. METHODS: Between April 2000 and June 2002, we enrolled 95 patients with moderate severity CHF from the Veterans Affairs Boston Healthcare System. Patients in the study intervention group attended a weekly RR group for 15 weeks and were requested to practice the techniques at home twice a day. A 15-week cardiac education (EDU) program was used as an alternative intervention, and usual care (UC) was the control group. The QOL questionnaires and a bicycle test were administered at baseline and after intervention or 15 to 19 weeks. RESULTS: Eighty-three (87%) of the 95 enrolled patients completed both baseline and post-intervention QOL measures (31 RR, 24 EDU, and 28 UC). No dropout bias was observed. The RR group had significantly better QOL change scores in peace-spiritual scales than did the UC group (P = .02), adjusting for baseline scores, time between assessments, age, education, diet, and medication, whereas no significant difference was observed between the EDU and UC groups. A similar trend was observed in emotional QOL (RR and UC group comparison, P = .07). No statistically significant intervention effect on physical QOL or exercise capacity was observed. CONCLUSIONS: A short RR intervention can improve some aspects of QOL in CHF patients.

Aged↗