Body composition of female wheelchair athletes

Wheelchair users undergo changes in body composition as a result of disability. In this study the distribution of bone mineral, lean and fat mass was assessed in highly-trained female wheelchair athletes and a reference group by dual-energy X-ray absorptiometry (DXA). The transferability of anthropometric equations commonly used in female groups was examined in order to establish a suitable field method of body composition assessment. The DXA total-body results indicated no difference between groups, but segmental analyses uncovered regional differences. The wheelchair athletes had greater BMD (p=0.088), more lean mass (p<0.001) and a lower percent fat (p=0.050) in their arms. The reverse was true of the legs (p< or =0.001). The trunk as a whole did not differ between groups. In general, the anthropometric equations showed a lack of transferability to the wheelchair group and tended to underestimate total percent body fat. Anthropometric measures such as body mass index (BMI) and waist girth showed strong correlations with body fat in the wheelchair group (BMI: r=0.90, p=0.001; waist: r=0.83, p=0.001), but weaker results in the reference group. It is recommended that specific anthropometric equations be developed for use in the absence of a 'gold standard' measure of body composition such as DXA.

Elaborated spaced-retrieval and prospective memory in mild Alzheimer's disease

Prospective memory, or the timely remembering of a planned action, is conceptualised as a cognitive process demanding episodic memory and executive attention. Impairments in these skills are characteristic of the cognitive decline in early Alzheimer's disease, providing an expectation of prominent prospective memory difficulties in this population, and yet surprisingly, memory performance in early Alzheimer's disease has rarely been evaluated within a prospective memory framework. In a preliminary study we demonstrated that older adults with early Alzheimer's disease (n=14), as compared to healthy older adults (n=14), were significantly impaired in a simple experimental paradigm of prospective remembering (a text-reading task). In a subsequent intervention study, we investigated the efficacy of spaced-retrieval for improving the prospective remembering performance of older adults with early Alzheimer's disease (n=16) compared to healthy older adults (n=16) under two learning conditions: a spaced-retrieval technique alone or spaced-retrieval combined with elaborated encoding of task. The majority of the Alzheimer's disease group (63%) demonstrated benefit in prospective remembering in the combined condition as compared to spaced-retrieval alone. Participants with Alzheimer's disease who demonstrated better executive attention (Trail Making- set-shifting) and/or better retrospective memory (Hopkins Verbal Learning Test-Revised- recognition) were more successful in the combined learning condition.

Pacific Islands Families Study: risk factors associated with otitis media with effusion among Pacific 2-year-old children

OBJECTIVE

This study examined the risk factors associated with middle ear disease in a cohort of Pacific 2-year-old children residing in New Zealand.

METHODS

The data were gathered as part of the Pacific Island Families: first 2 years of life (PIF) study in which 656 2-year-old were screened using tympanometry to identify children at risk for otitis media with effusion (OME) and other otological disorders.

RESULTS

Within this 2-year-old cohort of Pacific children, one set of factors significantly associated with OME was clustered around the respiratory and auditory health of the child over the past year. OME was more likely for children who were regularly suffering from fluid/pus discharge from ears (OR=2.10, 95% CI: 1.01-4.35), children with five or more coughs/colds in the last year (OR=1.90, 95% CI: 1.22-3.00), and children who frequently/constantly snored (OR=2.60, 95% CI: 1.09-6.23) to have OME. Those children who were treated at home for breathing problems were more that two times more likely to have OME (OR=2.61, 95% CI: 1.55-4.42). A second set of factors was clustered around environmental risks that exposed children to a large number of other children. Children who attended a day care centre for more than 20h were five times more likely (OR=5.21, 95% CI: 2.90-9.35) and those who regularly attended church (OR=2.78, 95% CI: 1.05-7.40) were almost three times more likely to have OME.

CONCLUSIONS

These findings portray a child compromised by persistent ear infections and general coughs and colds as being at increased risk of contracting OME. In line with international research these findings raise questions about the negative child health effects associated with the day care environment for young children.

Pacific Islands families study: the prevalence of chronic middle ear disease in 2-year-old Pacific children living in New Zealand

OBJECTIVE

The aim of this study was to determine the prevalence of chronic middle ear disease in 2-year-old Pacific children living in New Zealand.

METHODS

The data were gathered as part of the Pacific Islands Families: First Two Years of Life (PIF) Study in which 1001 two year olds were screened using tympanometry to identify children at risk for otitis media with effusion (OME) and other otological disorders. Those failing the screening tests were referred to Manukau Superclinic where they had a further tympanometry test, and if they failed this test, were followed up with a comprehensive otological examination by an otolaryngologist using otomicroscopy and pneumatic otoscopy.

RESULTS

Bilateral otitis media with effusion (OME) was the most common abnormality detected (N=102) with further cases of unilateral OME (N=8), and unilateral OME resolving (N=2). Other cases of OME were associated with acute otitis media (AOM), impacted wax (N=1), perforation (N=1), and mild retraction (N=2). Overall there were 118 children with unilateral or bilateral OME. AOM of any form was seen in nine cases. Retraction of the tympanic membrane was seen in 26 cases. The population prevalence among Pacific 2-year-old children was estimated as 25.4% for OME, 1.9% for AOM, and 26.9% for OME or AOM.

CONCLUSIONS

These findings reveal that over 25% of Pacific Island 2-year-old were affected by OME and recommend the consideration of national screening for OME and other otological disorders at this earlier age.

Listening to children and young people affected by parental HIV: Findings from a Scottish study

This study, conducted between 1999 and 2002, set out to explore the experiences of children and young people in Scotland with a parent or carer with HIV. The study had three elements: a postal survey of health and social work agencies, interviews with twenty-eight children and young people and a postal survey of schools. The study found little recognition from statutory agencies of the needs of affected children, whether in health, education or social work. Moreover, the children and young people who took part in the study bore a heavy burden in terms of stigma, family disruption and loss. Nevertheless, their greatest wish was to be seen as 'normal' children with 'normal' parents.

Reinforcement learning for a stochastic automaton modelling predation in stationary model-mimic environments

In this paper we propose a mathematical learning model for the feeding behaviour of a specialist predator operating in a random environment occupied by two types of prey, palatable mimics and unpalatable models, and a generalist predator with additional alternative prey at its disposal. A well known linear reinforcement learning algorithm and its special cases are considered for updating the probabilities of the two actions, eat prey or ignore prey. Each action elicits a probabilistic response from the environment that can be favorable or unfavourable. To assess the performance of the predator a payoff function is constructed that captures the energetic benefit from consuming acceptable prey, the energetic cost from consuming unacceptable prey, and lost benefit from ignoring acceptable prey. Conditions for an improving predator payoff are also explicitly formulated.

Simple broadband implementation of a phase contrast wavefront sensor for adaptive optics

The most critical element of an adaptive optics system is its wavefront sensor, which must measure the closed-loop difference between the corrected wavefront and an ideal template at high speed, in real time, over a dense sampling of the pupil. Most high-order systems have used Shack-Hartmann wavefront sensors, but a novel approach based on Zernike's phase contrast principle appears promising. In this paper we discuss a simple way to achromatize such a phase contrast wavefront sensor, using the pi/2 phase difference between reflected and transmitted rays in a thin, symmetric beam splitter. We further model the response at a range of wavelengths to show that the required transverse dimension of the focalplane phase-shifting spot, nominally lambda/D, may not be very sensitive to wavelength, and so in practice additional optics to introduce wavelengthdependent transverse magnification achromatizing this spot diameter may not be required. A very simple broadband implementation of the phase contrast wavefront sensor results.

Prophylactic mastectomy for the prevention of breast cancer

BACKGROUND

Breast cancer is the most common cancer and the second most common cause of cancer-related death among North American and Western European women. Recent progress in understanding the genetic basis of breast cancer, along with rising incidence rates, have resulted in increased interest in prophylactic mastectomy as a method of preventing breast cancer, particularly in those with familial susceptibility.

OBJECTIVES

The primary objective was to determine whether prophylactic mastectomy reduces death from any cause in women who have never had breast cancer and in women who have a history of breast cancer in one breast. The secondary objective was to examine the effect of prophylactic mastectomy on other endpoints including breast cancer incidence, breast cancer mortality, disease-free survival, physical morbidity, and psychosocial outcomes.

SEARCH STRATEGY

Electronic searches were performed in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Cancerlit, and the Science Citation Index.

SELECTION CRITERIA

Inclusion criteria were studies in English of any design type including randomized or nonrandomized controlled trials, cohort studies, case-control studies, and case series with at least ten participants. Participants included women at risk for breast cancer in at least one breast. Interventions included all types of mastectomy performed for the purpose of preventing breast cancer, including subcutaneous mastectomy, total or simple mastectomy, modified radical mastectomy, and radical mastectomy.

DATA COLLECTION AND ANALYSIS

Information on patients, interventions, methods, and results were extracted by at least two independent reviewers. Methodological quality was assessed based on how well each study minimized potential selection bias, performance bias, detection bias, and attrition bias. Data for each study were summarized descriptively; quantitative meta-analysis was not feasible due to heterogeneity of study designs and insufficient reporting. Data were analyzed separately for bilateral prophylactic mastectomy (BPM) and contralateral prophylactic mastectomy (CPM).

MAIN RESULTS

Twenty-three studies, including more than 4,000 patients, met inclusion criteria. No randomized or nonrandomized controlled trials were found. Most studies were either case series or cohort studies. All studies had methodological limitations, with the most common source of potential bias being systematic differences between the intervention and comparison groups that could potentially be associated with a particular outcome. Thirteen studies assessed the effectiveness of BPM. No study assessed all-cause mortality after BPM. All studies reporting on incidence of breast cancer and disease-specific mortality reported reductions after BPM. Nine studies assessed psychosocial measures; most reported high levels of satisfaction with the decision to have prophylactic mastectomy (PM) but more variable satisfaction with cosmetic results. Only one study assessed satisfaction with the psychological support provided by healthcare personnel during risk counseling and showed that more women were dissatisfied than satisfied with the support they received in the healthcare setting. Worry over breast cancer was significantly reduced after BPM when compared both to baseline worry levels and to the groups who opted for surveillance rather than BPM. Three studies reported body image/feelings of femininity outcomes, and all reported that a substantial minority (about 20%) reported BPM had adverse effects on those domains. Six studies assessed contralateral prophylactic mastectomy. Studies consistently reported reductions in contralateral incidence of breast cancer but were inconsistent about improvements in disease-specific survival. Only one study attempted to control for multiple differences between intervention groups, and this study showed no overall survival advantage for CPM at 15 years. Two case series were exclusively focused on adverse events from prophylactic mastectomy with reconstruction, and both reported rates of unanticipated re-operations from 30% to 49%.

REVIEWERS' CONCLUSIONS

While published observational studies demonstrated that BPM was effective in reducing both the incidence of, and death from, breast cancer, more rigorous prospective studies (ideally randomized trials) are needed. The studies need to be of sufficient duration and make better attempts to control for selection biases to arrive at better estimates of risk reduction. The state of the science is far from exact in predicting who will get or who will die from breast cancer. By one estimate, most of the women deemed high risk by family history (but not necessarily BRCA 1 or 2 mutation carriers) who underwent these procedures would not have died from breast cancer, even without prophylactic surgery. Therefore, women need to understand that this procedure should be considered only among those at very high risk of the disease. For women who had already been diagnosed with a primary tumor, the data were particularly lacking for indications for contralateral prophylactic mastectomy. While it appeared that contralateral mastectomy may reduce the incidence of cancer in the contralateral breast, there was insufficient evidence about whether, and for whom, CPM actually improved survival. Physical morbidity is not uncommon following PM, and many women underwent unanticipated re-operations (usually due to problems with reconstruction); however, these data need to be updated to reflect changes in surgical procedures and reconstruction. Regarding psychosocial outcomes, women generally reported satisfaction with their decisions to have PM but reported satisfaction less consistently for cosmetic outcomes, with diminished satisfaction often due to surgical complications. Therefore, physical morbidity and post-operative surgical complications were areas that should be considered when deciding about PM. With regard to emotional well-being, most women recovered well postoperatively, reporting reduced cancer worry and showing reduced psychological morbidity from their baseline measures; exceptions also have been noted. Of the psychosocial outcomes measured, body image and feelings of femininity were the most adversely affected.

Age-related differences in parameters of feline immune status

In order to assess age-related differences in feline immune status, 101 domestic short haired cats were assigned to two groups, adult (2-5 years, n=50) and senior (10-14 years, n=51). Analyses of leucocyte populations, lymphocyte subsets, complement activity, serum immunoglobulins and acute-phase proteins were undertaken and revealed significant differences between the two groups. The senior group had significantly lower WBC, lymphocyte and eosinophil counts than the adult group. Neutrophil, monocyte and basophil counts did not differ between the groups. Flow cytometry analysis, in combination with differential WBC data, revealed that the absolute values (cells/l) of T-cells, B-cells and natural killer (NK) cells were significantly lower in the older animals. While serum immunoglobulins IgA and IgM were higher in the senior group when compared with the adult group, no significant differences were observed in complement activity or in serum acute-phase proteins. Our findings suggest that age-related changes to parameters of immune status in the feline model are likely to follow a similar pattern to those observed in other long-lived mammalian species.

Cultural case management of latent tuberculosis infection

SETTING

The proportion of tuberculosis (TB) among foreign-born individuals in the United States is steadily increasing. Treatment of latent TB infection can prevent future cases of disease, although generally only 60% of patients who start a 6-month regimen of isoniazid complete therapy.

OBJECTIVE

Cultural case management--employing case manager cultural mediators who serve patient-defined needs in addition to performing TB control functions--may improve results of testing and treatment in one high-risk group, new refugees.

DESIGN

A cultural case management approach was established for finding and treating latent TB infection among three groups of new refugees: from the former Soviet Union (FSU), former Yugoslavia (FY), and Somalia.

RESULTS

From July 1999 through December 2000, treatment was offered to 442 refugees, of whom 389 (88%) started and 319 (82%) completed therapy. The completion rate among starters from the FSU was 76%, for those from FY it was 94% and for those from Somalia it was 88%. Among all refugees to whom treatment was offered, 319/442 (72%) completed therapy.

CONCLUSION

Cultural case management may be a useful tool for expanding treatment of latent TB infection among foreign-born individuals.

BARCODE-ALL: accelerated and cost-effective genetic risk stratification in acute leukemia using spectrally addressable liquid bead microarrays

An increasing number of risk-stratifying genetic lesions in acute leukemia are being discovered and characterized. To translate this important and increasing volume of information from the research laboratory into effective clinical care, however, new, fast and comprehensive assays are needed. Toward this end, we have developed a two-stage multiplexing assay of broad applicability, which combines multiplex polymerase chain reaction with multiplex detection on spectrally addressable liquid bead microarrays. Using pediatric lymphoblastic leukemia as a model system, we demonstrate that all seven of the fusion transcripts resulting from risk-stratifying chromosomal translocations can be assayed in a single well of a 96-well multiplate with 100% specificity and sensitivity, within 6 h of specimen collection. The assay is automatic and high throughput and represents a significant improvement over previously available assays targeting the same genetic changes. We conclude that user-defined assays that multiplex both target selection and detection may have broad applicability in the management of hematological malignancies.

Analysis of logistic growth models

A variety of growth curves have been developed to model both unpredated, intraspecific population dynamics and more general biological growth. Most predictive models are shown to be based on variations of the classical Verhulst logistic growth equation. We review and compare several such models and analyse properties of interest for these. We also identify and detail several associated limitations and restrictions.A generalized form of the logistic growth curve is introduced which incorporates these models as special cases. Several properties of the generalized growth are also presented. We furthermore prove that the new growth form incorporates additional growth models which are markedly different from the logistic growth and its variants, at least in their mathematical representation. Finally, we give a brief outline of how the new curve could be used for curve-fitting.

The prediction of amphiphilic alpha-helices

A number of sequence-based analyses have been developed to identify protein segments, which are able to form membrane interactive amphiphilic alpha-helices. Earlier techniques attempted to detect the characteristic periodicity in hydrophobic amino acid residues shown by these structure and included the Molecular Hydrophobic Potential (MHP), which represents the hydrophobicity of amino acid residues as lines of isopotential around the alpha-helix and analyses based on Fourier transforms. These latter analyses compare the periodicity of hydrophobic residues in a putative alpha-helical sequence with that of a test mathematical function to provide a measure of amphiphilicity using either the Amphipathic Index or the Hydrophobic Moment. More recently, the introduction of computational procedures based on techniques such as hydropathy analysis, homology modelling, multiple sequence alignments and neural networks has led to the prediction of transmembrane alpha-helices with accuracies of the order of 95% and transmembrane protein topology with accuracies greater than 75%. Statistical approaches to transmembrane protein modeling such as hidden Markov models have increased these prediction levels to an even higher level. Here, we review a number of these predictive techniques and consider problems associated with their use in the prediction of structure / function relationships, using alpha-helices from G-coupled protein receptors, penicillin binding proteins, apolipoproteins, peptide hormones, lytic peptides and tilted peptides as examples.

Nutrient partitioning during adolescent pregnancy

Human adolescent mothers have an increased risk of delivering low birth weight and premature infants with high mortality rates within the first year of life. Studies using a highly controlled adolescent sheep paradigm demonstrate that, in young growing females, the hierarchy of nutrient partitioning during pregnancy is altered to promote growth of the maternal body at the expense of the gradually evolving nutrient requirements of the gravid uterus and mammary gland. Thus, overnourishing adolescent dams throughout pregnancy results in a major restriction in placental mass, and leads to a significant decrease in birth weight relative to adolescent dams receiving a moderate nutrient intake. High maternal intakes are also associated with increased rates of spontaneous abortion in late gestation and, for ewes delivering live young, with a reduction in the duration of gestation and in the quality and quantity of colostrum accumulated prenatally. As the adolescent dams are of equivalent age at the time of conception, these studies indicate that nutritional status during pregnancy rather than biological immaturity predisposes the rapidly growing adolescents to adverse pregnancy outcome. Nutrient partitioning between the maternal body and gravid uterus is putatively orchestrated by a number of endocrine hormones and, in this review, the roles of both maternal and placental hormones in the regulation of placental and fetal growth in this intriguing adolescent paradigm are discussed. Impaired placental growth, particularly of the fetal component of the placenta, is the primary constraint to fetal growth during late gestation in the overnourished dams and nutritional switch-over studies indicate that high nutrient intakes during the second two-thirds of pregnancy are most detrimental to pregnancy outcome. In addition, it may be possible to alter the nutrient transport function of the growth-restricted placenta in that the imposition of a catabolic phase during the final third of pregnancy in previously rapidly growing dams results in a modest increase in lamb birth weight.

The relationship between gender, depression, and self-esteem in children who have witnessed domestic violence

OBJECTIVE

To investigate whether there are measurable gender differences in self-esteem and depression in elementary school-age children who have witnessed domestic violence.

METHOD

Forty-five elementary school-age children who were identified as having witnessed domestic violence, and their teachers were surveyed for self-esteem, depression, and classroom behaviors. The results were compared between males and females using linear regression modeling.

RESULTS

No significant gender differences were found for self-esteem and depression. An interaction between gender and post-traumatic stress was found to play a significant role in the interpretation of the results.

CONCLUSIONS

Results indicated that higher levels of symptoms indicative of post-traumatic stress were associated with greater numbers of depressive symptoms and lower self-esteem for boys who had witnessed domestic violence. The results appeared similar to previous work with children and their emotional reactions to divorce.

Evaluation of serologic disease markers in a population-based cohort of patients with ulcerative colitis and Crohn's disease

BACKGROUND

The sensitivity of assays for antineutrophil cytoplasmic antibody (ANCA), anti-Saccharomyces cerevisiae antibody (ASCA), and antipancreatic antibody (PAB) in different laboratories is unknown. Likewise, the sensitivity and diagnostic usefulness of these assays in patients with inflammatory bowel disease (IBD) in the community is unknown.

METHODS

An incidence cohort of 290 patients with IBD were offered participation in the study. Blood was obtained from 162 patients (56%) (83 with ulcerative colitis, 79 with Crohn's disease) who agreed to participate. ANCA was determined in five laboratories. ASCA in two laboratories, and PAB in one laboratory.

RESULTS

In ulcerative colitis, the sensitivity of ANCA determined in five laboratories varied widely, ranging from 0-63%. In Crohn's disease, the sensitivity of ASCA determined in two laboratories did not vary significantly, ranging from 39-44%; and the sensitivity of PAB determined in one laboratory was 15%. The optimal diagnostic usefulness was obtained from one laboratory where the positive predictive values of a positive ANCA assay combined with a negative ASCA assay for ulcerative colitis, and a negative ANCA combined with a positive ASCA for Crohn's disease, were 75% and 86%, respectively.

CONCLUSIONS

In patients with IBD, the sensitivity of ANCA varied widely in different laboratories, whereas the prevalence of ASCA was similar. The positive predictive values of the ANCA assay combined with the ASCA assay for ulcerative colitis and Crohn's disease are high enough to be clinically useful.