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PubMed2001

Clinical outcomes in reduction mammaplasty: a systematic review and meta-analysis of published studies.

This systematic review and meta-analysis were undertaken to determine whether reduction mammaplasty improves measurable outcomes in women with breast hypertrophy. A systematic review of the literature in 5 languages from 1985 until March 1999 was performed, and data were compared for meta-analysis. Eligible studies were both experimental and observational and involved women with preoperative physical and/or psychosocial signs and symptoms who underwent reduction mammaplasty for breast hypertrophy. Outcomes assessed were postoperative physical signs and symptoms such as shoulder pain, shoulder (bra strap) grooving, and quality-of-life domains, such as physical and psychological functioning, and were expressed primarily as risk differences (RDs). Twenty-nine studies of 4173 patients met all eligibility criteria. Reduction mammaplasty was associated with a statistically significant improvement in physical signs and symptoms involving shoulder pain (RD, 0.71 [95% confidence interval (CI), 0.62-0.80]); shoulder grooving (RD, 0.69 [95% CI, 0.60-0.78]); upper/lower back pain (RD, 0.59 [95% CI, 0.48-0.70]); neck pain (RD, 0.50 [95% CI, 0.37-0.64]); intertrigo (RD, 0.44 [95% CI, 0.34-0.54]); breast pain (RD, 0.36 [95% CI, 0.17-0.55]); headache (RD, 0.28 [95% CI, 0.11-0.46]); and pain/numbness in the hands (RD, 0.11 [95% CI, 0.04-0.18]). The quality-of-life parameter of physical functioning was also statistically significant (RD, 0.58 [95% CI, 0.44-0.71]), while psychological functioning was not significant (RD, 0.46 [95% CI, 0.00-1.00]). The evidence suggests that women undergoing reduction mammaplasty for breast hypertrophy have significant postoperative improvement in preoperative signs and symptoms, quality of life, or both.

Adult↗
PubMed2004

Study of traffic pollution by metals in Seville (Spain) by physical and chemical speciation methods.

Eighty-three samples of atmospheric particles were collected at a representative traffic site in the Mediterranean city of Seville during a period of one year. Urban particles were collected on quartz filters with a high-volume sampler coupled with a cascade impactor which separates particles into six size ranges: >10, 10-4.9, 4.9-2.7, 2.7-1.3, 1.3-0.6, and <0.6 microm. The total metal content, its distribution by size (physical speciation), and the concentrations of different chemical forms (chemical speciation) in particles less than 0.6 microm were determined. The chemical speciation scheme furnished four fractions: soluble and exchangeable metals; carbonates, oxides, and reducible metals; oxidisable and sulfidic metals bound to organic matter; and residual metals. The samples were analysed by ICP-OES for Pb, Ni, Cd, S, Fe, Zn, Cu, Ba, Mn, and V. Gaseous pollutants, traffic intensities, and primary meteorological data provided by the atmospheric and traffic networks were statistically related to the analytical data. Analytical and statistical results from physical and chemical speciation singled out Ba as a valid tracer of vehicular traffic, instead of Pb, in cities with high traffic density. Another important relationship was found between Pb and Cu. Physical speciation of lead showed that the major risk for health was from fine particles less than 2.7 microm, because particles between 2.7 and 0.6 microm were the size fractions of the total suspended particles with the major mass abundance of lead (mainly particles between 2.7 and 1.3 microm) and because particles less than 0.6 microm were the fraction of airborne particles most abundant in the urban air. Chemical speciation results showed that special attention must be taken with Ni and Cd concentrations, because of their high potential bioavailability, mainly a result of the high solubility of the chemical forms of Ni in the finest particles.

Air Pollutants↗
PubMed1975

Sampling in physical therapy research.

Although the importance of appropriate statistical analyses of the results of physical therapy research is well documented, the theory and methodology of sampling, the procedure by which the data of research are usually obtained, has received much less attention in the physical therapy literature. To help fill this gap, some of the basic concepts and techniques of sampling are discussed.

Physical Therapy Modalities↗
PubMedDate not supplied

Checklist of Health Promotion Environments at Worksites (CHEW): development and measurement characteristics.

PURPOSE: Health promotion policy frameworks, recent theorizing, and research all emphasize understanding and mobilizing environmental influences to change particular health-related behaviors in specific settings. The workplace is a key environmental setting. The Checklist of Health Promotion Environments at Worksites (CHEW) was designed as a direct observation instrument to assess characteristics of worksite environments that are known to influence health-related behaviors. METHODS: The CHEW is a 112-item checklist of workplace environmental features hypothesized to be associated, both positively and negatively, with physical activity, healthy eating, alcohol consumption, and smoking. The three environmental domains assessed are (1) physical characteristics of the worksite, (2) features of the information environment, and (3) characteristics of the immediate neighborhood around the workplace. The conceptual rationale and development studies for the CHEW are described, and data from observational studies of 20 worksites are reported. RESULTS: The data on CHEW-derived environmental attributes showed generally good reliability and identified meaningful sets of variables that plausibly may influence health-related behaviors. With the exception of one information environment attribute, intraclass correlation coefficients ranged from 0.80 to 1.00. Descriptive statistics on selected physical and information environment characteristics indicated that vending machines, showers, bulletin boards, and signs prohibiting smoking were common across worksites. Bicycle racks, visible stairways, and signs related to alcohol consumption, nutrition, and health promotion were relatively uncommon. CONCLUSIONS: These findings illustrate the types of data on environmental attributes that can be derived, their relevance for program planning, and how they can characterize variability across worksites. The CHEW is a promising observational measure that has the potential to assess environmental influences on health behaviors and to evaluate workplace health promotion programs.

Health Behavior↗
PubMed1992

Objective clinical evaluation of physical impairment in chronic low back pain.

The aim of this study was to investigate physical impairment in patients with chronic low back pain, to develop a method of clinical evaluation suitable for routine use, and to consider the relationship between pain, disability, and physical impairment. Twenty-seven physical tests were investigated. Permanent anatomic and structural impairments of spinal deformities, spinal fractures, surgical scarring, and neurologic deficits were excluded as not relevant to the patient with low back pain in the absence of nerve root involvement or previous surgery. Three consecutive 20-patient reproducibility studies were used to develop reliable methods of examination for 23 of the tests. Only four tests were excluded as unreliable: sacral angle, pelvic tilt, and separate lumbar and pelvic extension, none of which are part of routine clinical examination or have any proven relationship to disability. The remaining 23 physical tests were evaluated in 70 asymptomatic subjects and 120 patients with chronic low back pain. Passive knee flexion, passive hip flexion, hip flexion strength, hip abduction strength, pain reproduction on each of these tests, and the prone extension strength test were excluded because they were too closely related to nonorganic and behavioral responses to examination. Eight tests successfully discriminated patients with low back pain from normal subjects and were significantly related to self-report disability in activities of daily living: pelvic flexion, total flexion, total extension, lateral flexion, straight leg raising, spinal tenderness, bilateral active straight leg raising, and sit-up. Factor analysis failed to demonstrate an underlying statistical dimension of physical impairment. However, an empirical combination of total flexion, total extension, average lateral flexion, average straight leg raising, spinal tenderness, bilateral active straight leg raising, and sit-up provided an equally satisfactory alternative. Simple cut-offs from normal subjects made the scale simple and quick to use. This final scale successfully discriminated 78% of patients and normal subjects and explained 25% of the variance of disability, with a specificity of 86% and sensitivity of 76%. This scale provides an objective clinical evaluation that meets the criteria for evaluating physical impairment, yet is simple, reliable, and suitable for routine clinical use. It should, however, be emphasized that all the tests included in the final scale are measures of current functional limitation rather than of permanent anatomic or structural impairment. This raises questions about the physical basis of permanent disability due to chronic low back pain.

Activities of Daily Living↗
PubMed2005

The relationship between physical maltreatment and substance use among adolescents: a survey of 95,788 adolescents in Hong Kong.

PURPOSE: To determine the prevalence of corporal punishment and the infliction of injuries from a beating occurring without provocation in the previous 6 months among secondary school children in Hong Kong, and to examine the associations between these two forms of physical maltreatment with substance-use-related behaviors and attitudes. METHODS: Using secondary data, a cross-sectional, self-administered, anonymous survey of 95,788 secondary school students was conducted in Hong Kong. RESULTS: The prevalence of physical maltreatment showed statistically significant associations with younger age, attendance in Chinese-speaking day schools, temporary housing, residence with only one parent, poorer parental relationship, greater peer influence, perceptions of excessive academic pressure, and feelings of being blamed for poor academic performance. Adolescents who had experienced corporal punishment were more likely to be current users of alcohol (OR = 1.11), tobacco (OR = 1.31), psychoactive substances (OR = 1.60), or heroin (OR = 1.90). Those who had been beaten to injury by a family member without provocation within the past 6 months also were more likely to be current users of alcohol (OR = 1.35), tobacco (OR = 1.65), psychoactive substances (OR = 2.39), and heroin (OR = 3.07). Additionally, students who experienced physical maltreatment were more likely to be acquainted with habitual substance users, have better access to psychoactive substances, to have engaged in sex after abusing drugs, have obtained money from illegal sources to purchase drugs, and believe that psychoactive substances are not harmful or addictive. CONCLUSIONS: Physical maltreatment showed strong associations with drug-related behaviors and attitudes, after adjusting for potential confounders. Further longitudinal studies are required to understand the causal direction of the relationship.

Adolescent↗
PubMed1997

Moving toward a core curriculum in Schools of the Allied Health Professions: knowledge and skills considered important by department chairs in four disciplines.

An adaptation of the Delphi method was used in four parallel studies to survey chairs of baccalaureate programs in clinical laboratory sciences, health information management, occupational therapy, and physical therapy in schools of the allied health professions which held membership in the Association of Schools of the Allied Health Professions. The purpose was to assist the chairs in coming to consensus regarding requisite knowledge and skills of graduates beyond those required for professional accreditation and credentialing, and prerequisite or cognate courses that may be utilized to develop them. Three rounds of questionnaires were administered to each group. The final round was completed by 45 chairs in clinical laboratory sciences (83% of the population); 18 in health information management (86%); 18 in occupational therapy (56%); and 24 in physical therapy (67%). Statistical analysis of third round responses via one-sample, one-sided Z tests indicated consensus among the chairs in the four disciplines on 16 items of knowledge and skills as most important for graduates. Similar consensus was not evident, however, regarding courses to develop the knowledge and skills, with only two courses considered most important by all four groups of chairs.

Allied Health Personnel↗
PubMed1983

Objective evaluation of hand function in scleroderma patients to assess effectiveness of physical therapy.

A system was developed to evaluate the hand function of patients with scleroderma objectively in terms of joint contracture, range of movement, dexterity, strength, and skin compliance. Twelve patients with progressive systemic sclerosis were evaluated using this technique to determine the effectiveness of classic physical therapy methods. A statistically significant improvement in hand function was found after a single physical therapy treatment. This conservative mode of treatment may contribute to improved hand function in patients with scleroderma.

Biomechanical Phenomena↗
PubMed1993

Effects of physical inactivity on all-cause mortality risk in Upper Bavaria.

The effect of physical activity on all-cause mortality was examined using a representative random sample of 1,536 persons (15 years and older) in three communities in Upper Bavaria. 27.0% of the respondents reported regular and 26.2% occasional physical exercise. During the 5-year follow-up 5.1% (n = 79) of the original sample died. Using a logistic regression model, the relation between physical activity and mortality was measured by the odds ratio, with subjects reporting regular physical activity as the reference group. Crude mortality risk was significantly higher among the physically inactive (men: 3.97; women: 4.36) but not among respondents practising occasionally (men: 1.67; women: 1.24). After adjustment for potential confounding variables (age, social class, physical and mental health), the mortality risk was elevated but not statistically significant for the physically inactive (men: 1.76; women: 1.51) and for the group practising occasionally (men: 1.50; women: 1.14).

Adolescent↗
PubMed1993

Conformational preference functions for predicting helices in membrane proteins.

A suite of FORTRAN programs, PREF, is described for calculating preference functions from the data base of known protein structures and for comparing smoothed profiles of sequence-dependent preferences in proteins of unknown structure. Amino acid preferences for a secondary structure are considered as functions of a sequence environment. Sequence environment of amino acid residue in a protein is defined as an average over some physical, chemical, or statistical property of its primary structure neighbors. The frequency distribution of sequence environments in the data base of soluble protein structures is approximately normal for each amino acid type of known secondary conformation. An analytical expression for the dependence of preferences on sequence environment is obtained after each frequency distribution is replaced by corresponding Gaussian function. The preference for the alpha-helical conformation increases for each amino acid type with the increase of sequence environment of buried solvent-accessible surface areas. We show that a set of preference functions based on buried surface area is useful for predicting folding motifs in alpha-class proteins and in integral membrane proteins. The prediction accuracy for helical residues is 79% for 5 integral membrane proteins and 74% for 11 alpha-class soluble proteins. Most residues found in transmembrane segments of membrane proteins with known alpha-helical structure are predicted to be indeed in the helical conformation because of very high middle helix preferences. Both extramembrane and transmembrane helices in the photosynthetic reaction center M and L subunits are correctly predicted. We point out in the discussion that our method of conformational preference functions can identify what physical properties of the amino acids are important in the formation of particular secondary structure elements.

Animals↗
PubMed1978

Lifestyle, health and disease: a comparison between Papua New Guinea and Australia.

The proposition that lifestyle is a major determinant of community health is explored by contrasting the features of a rural subsistence community in the highlands of Papua New Guinea and the features of the community in urbanized, industrialized Australia. Reference is made to differences in physical environment, housing, work, social situation, human relationships, patterns of disease, population statistics, diet, growth, obesity, physical fitness, blood lipid concentrations, blood pressure, salt intake and the occurrence of hypertension, diabetes, cardiovascular disease and signs of degenerative changes in various tissues. The Papua New Guinea community is seen as a self-reliant, self-contained, socially cohesive subsistence society whose members are well adapted to their physical and social environment, free from major degenerative cardiovascular diseases, with little overt psychiatric illness, but with a heavy burden of infectious disease, with marginal nutritional levels of degenerative disease and disease from psychological stress. It is clear that health, in its fullest sense, is not the prerogative of any one type of society.

Adolescent↗
PubMed1992

Quality of life in bone tumor patients comparing limb salvage and amputation of the lower extremity.

In 33 long-term survivors of lower extremity bone cancer quality-of-life data were studied following limb salvage compared to amputation. Self-report questionnaires, semistructured interviews and visual analog scales were used to measure psychoneurotic and somatical distress, activities of daily living, self-esteem, and adjustment to illness. Fourteen patients with limb salvage (age 13-56 years, median 24) and 19 patients with an amputation (age 21-53 years, median 27) were evaluated 2-17 years (median 10 years) after surgery. The differences between the two groups were not statistically significant. However, physical complaints were reported more often by limb salvage patients, whereas the amputees showed a trend toward lower self-esteem and isolation in social life, due to their disability. Both groups felt equal diminution of quality of life and disability as measured on the visual analog scale. These findings could support the cosmetic advantage of limb salvage compared to amputation.

Adolescent↗
PubMed1998

New DNA sequence rules for high affinity binding to histone octamer and sequence-directed nucleosome positioning.

DNA sequences that position nucleosomes are of increasing interest because of their relationship to gene regulation in vivo and because of their utility in studies of nucleosome structure and function in vitro. However, at present our understanding of the rules for DNA sequence-directed nucleosome positioning is fragmentary, and existing positioning sequences have many limitations. We carried out a SELEX experiment starting with a large pool of chemically synthetic random. DNA molecules to identify those individuals having the highest affinity for histone octamer. A set of highest-affinity molecules were selected, cloned, and sequenced, their affinities (free energies) for histone octamer in nucleosome reconstitution measured, and their ability to position nucleosomes in vitro assessed by native gel electrophoresis. The selected sequences have higher affinity than previously known natural or non-natural sequences, and have a correspondingly strong nucleosome positioning ability. A variety of analyses including Fourier transform, real-space correlation, and direct counting computations were carried out to assess non-random features in the selected sequences. The results reveal sequence rules that were already identified in earlier studies of natural nucleosomal DNA, together with a large set of new rules having even stronger statistical significance. Possible physical origins of the selected molecules' high affinities are discussed. The sequences isolated in this study should prove valuable for studies of chromatin structure and function in vitro and, potentially, for studies in vivo.

Base Composition↗
PubMed1994

A strengthening experience? Mental distress during military service. A study of Norwegian army conscripts.

Conscription compels 70% of male Norwegians to invest 1 year of their lives in military training. For 19-to 20-year-old men, the military service is an important arena of secondary socialization. In a cross-sectional study of mental health in army conscripts using the 12-item General Health Questionnaire (GHQ), the case prevalence was 48% (cut-off 2/3). This was remarkably high, given that the study population had been screened for mental disease on several occasions, and a large number of recruits with symptoms of mental disease had been excluded before the survey began. Statistical analyses indicated that the high case prevalence was mainly due to situational factors. Four dimensions were identified: (1) social relations with officers, peers and family, (2) structural factors inherent in the system of obligatory military service, (3) the meaningfulness of daily tasks and (4) financial problems. GHQ caseness was statistically associated with physical inactivity and consumption of junk-food, tobacco, alcohol and cannabis. It is concluded that military service in its present form may have undesirable consequences both for civilian society and for military efficiency. Recruits need help to cope with the complex psychosocial and transactional challenges of military service.

Adaptation, Psychological↗
PubMed1975

Life and chirality beyond the earth.

An attempt is made to show that the phenomenon of chirality- of which optical activity is but one consequence- is by no means restricted to life on Earth, but is common throughout the universe. Several independent sources have been investigated including: statistical fluctuations; stereoselective physical factors; and energetic differences between enantiomeric molecules. It is emphasised that a search for chirality as an indicator for life elsewhere in space provides an excellent tool for the fascinating question of exobiology. Still one must be aware of the limitations of the experimental methods and their interpretations.

Extraterrestrial Environment↗