The psychological wellbeing of patients following excision of a pilonidal sinus

OBJECTIVE

To explore the effects of a pilonidal sinus wound on patients' psychological wellbeing.

METHOD

An interpretive descriptive approach, using the Model of Living conceptual framework, guided data collection and analysis. The Model of Living was chosen to elicit information on how a pilonidal sinus wound affected activities of living. Participants were recruited from a database of a community nursing service, using purposive sampling, until data saturation was evident. Semi-structured interviews were used to collect the data. Data were examined for frequent patterns, which were organised into themes.

RESULTS

Seven males and four females with ages ranging 17-39 years were selected through purposive sampling. Five participants reported that their wound affected their psychological wellbeing. Three themes and eight sub themes were identified from the data: adaption, perception and control. Depression and stress were associated with pain, physical inactivity, body weight changes and delayed wound healing.

CONCLUSION

A pilonidal sinus wound can affect the psychological wellbeing of patients through pain,physical inactivity, changed body weight and delayed wound healing. Pre-existing conditions could also be exacerbated by the wound.

Regulation of mixed lineage kinase 3 is required for Neurofibromatosis-2-mediated growth suppression in human cancer

The Neurofibromatosis-2 (NF2) tumor suppressor merlin negatively regulates cell proliferation in numerous cell types. We have previously shown that the NF2 protein (merlin/schwannomin) associates with mixed lineage kinase 3 (MLK3), a mitogen-activated protein kinase (MAPK) kinase kinase that is required for the proliferation of normal and neoplastic cells. In this study, we show that merlin inhibits MLK3 activity, as well as the activation of its downstream effectors, B-Raf, extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). The ability of merlin to regulate MLK3 activity requires a direct association between MLK3 and residues in the C-terminal region of merlin. Merlin integrates Rho GTPase family signaling with MAPK activity by inhibiting the binding between MLK3 and its upstream activator, Cdc42. Furthermore, we demonstrate that MLK3 is required for merlin-mediated suppression of cell proliferation and invasion. Collectively, these results establish merlin as a potent inhibitor of MLK3, ERK and JNK activation in cancer, and provide a mechanistic link between deregulated MAPK and Rho GTPase signaling in NF2 growth control.

Influence of cyclohexane vapor on stick-slip friction between mica surfaces

Stick-slip friction between mica surfaces under cyclohexane vapor has been investigated with the Surface Force Apparatus. The dynamic shear stress decreased from 60 to 10 MPa with increasing relative vapor pressure (rvp) from 5% to 50%. Between a rvp of 50% and 80%, the shear stress remained at approximately 10 MPa, with a slight decrease on increasing the rvp. At a rvp greater than 80%, the values of shear stress were below 5 MPa. The stick-slip behavior was observed in the rvp range of 20% to saturation. When the rvp reached 20%, stick-slip appeared but faded out with sliding time. At a rvp greater than 50%, the stick-slip pattern was stable without fading. By taking into account the size of the meniscus formed by capillary condensation of the liquid around the contact area and the Laplace pressure, the dependence of shear stress and the stick-slip modulation on rvp suggests that the origin of the stick-slip observed in cyclohexane vapor is as follows: At a rvp greater than 50%, where stable sick-slip is observed, the stick-slip caused by the cyclohexane layering in the contact area is of essentially the same origin as that observed with mica surfaces sliding in bulk cyclohexane liquid. As with the bulk liquid experiment, decreasing the layer thickness (or the number of the layers) between the surfaces increases the shear stress at the onset of slip. In the vapor phase experiments, the stick-slip is enhanced by the increase of the negative Laplace pressure in the capillary condensed liquid, thereby forcing the surfaces toward each other more strongly with decreasing rvp. In the rvp range between 20% and 50%, where the fading stick-slip is observed, the condensate liquid seeps into the contact area under the influence of the applied tangential force and thus triggers the slip motion. Due to the small condensation volume, the liquid condensed around the contact area is exhausted in the process of repeating stick-slip. As the slip length is limited to the meniscus size, the stick-slip amplitude becomes smaller, and eventually the surfaces start sliding without stick-slip.

Psychological consequences of maxillofacial trauma: a preliminary study

AIMS

To identify the prevalence of post-traumatic psychological symptoms after maxillofacial trauma and prognostic factors related to poor outcome.

METHODS

Thirty-nine patients were assessed within 10 days of injury and 24 again 4-6 weeks later using five standardised self-report measures on each occasion and a short structured interview at the time of initial contact.

RESULTS

Specific post-traumatic psychological symptoms were present at initial assessment in 21 patients (54%), with 9 (41%) meeting diagnostic criteria for post-traumatic stress disorder at review 4-6 weeks later. Other psychiatric problems, such as anxiety and depression, were identified by the General Health Questionnaire and the Hospital Anxiety and Depression Scale. Characteristics associated with poorer outcome included: a previous history of psychological distress; fear of the unknown, and female sex.

CONCLUSION

These findings highlight the adverse psychological effect of maxillofacial trauma both immediately after the event and 4-6 weeks after injury. Proper assessment of injured patients must include psychological aspects and further research is needed to identify the most appropriate response.

The use of mirrors during an assembly task: a study of ergonomics and productivity

Industrial assembly tasks often require awkward, sustained neck and/or shoulder postures that can lead to increased musculoskeletal discomfort and reduced productivity. The aim of this study was to investigate the effects of mirror and periscope visual aids as ergonomic interventions designed to eliminate awkward postures of the cervicobrachial region during assembly tasks. Participants simulated a simple assembly task by using a cordless screwdriver to drive screws into a pre-tapped aluminium block. Trials of 15 min were run for each of four distinct assembly workstation configurations: industry standard (in-line screwdriver, work at elbow height, no visual aid); pistol grip (pistol grip screwdriver, work at shoulder height, no visual aid); mirror (in-line screwdriver, work at elbow height, single mirror visual aid); and periscope (in-line screwdriver, work at elbow height, two-mirror visual aid system). Muscular activity, discomfort, body posture, productivity and operator subjective assessment were recorded to determine the effects of the visual aid interventions. The results show that when comparing the interventions to the industry standard condition, there was a 45% reduction in average cervical erector spinae activity, a 90% reduction in average neck flexion angle and a 72% reduction in neck discomfort with the interventions. When comparing these interventions to the pistol grip condition there was an 80% reduction in activity of the dominant side deltoid, a 92% reduction in shoulder flexion angle and an 81% decrease in shoulder discomfort with the interventions. Productivity was greatest in the industry standard configuration followed by the pistol grip (9% lower), the periscope (13% lower) and the mirror (23% lower) configurations. A follow-up study that compared the productivity of the periscope configuration with that of the industry standard configuration showed that within a 4-h work period this productivity differential decreased by over 33%.

Seasonal training and performance of competitive swimmers

To determine the relationship between prescribed training and seasonal-best swimming performance, we surveyed 24 swim coaches and 185 of their age-group and open-class swimmers specializing in sprint (50 and 100 m) and middle-distance (200 and 400 m) events in a summer and winter season. We expressed effects on training as either multiples of swimmers' standard deviations (effect size, ES) or as correlations (r). Coaches prescribed higher mileage and longer repetitions of lower intensity to middle-distance swimmers than to sprinters (ES = 0.4-1.5); as competitions approached, repetition intensity and duration of rest intervals increased (ES = 0.5-0.9), whereas session and repetition distances decreased (ES = 0.4-1.3). The 95% likely ranges of the true values for these effects were about +/- 0.3. Weekly mileage swum at an easy or moderate pace remained at almost 60% of the total throughout both seasons. Interval training reduced gradually from 40% of total distance in the build-up to 30% at the end of tapering. Older swimmers had shorter rests and swam more miles (r = 0.5-0.8). After partialling out the effects of age on performance (r = 0.7-0.8), better performance was significantly associated only with greater weekly mileage (r = 0.5-0.8) and shorter duration of rest intervals (r = 0.6-0.7) in middle-distance swimmers. We conclude that periodization of training and differences in training between sprint and middle-distance events were broadly in accord with principles of specificity. Strong effects of specificity on performance were not apparent, but weak effects might have been detected with a larger sample.

A-bomb survivors: factors that may lead to a re-assessment of the radiation hazard

BACKGROUND

The study cohort of the survivors of the A-bombs in Japan, used as the basis of the internationally accepted estimates of cancer radiation risk, was collected more than 5 years after the bombing and did not include those who died of bomb-related injuries before that date. This paper tests whether the people who survived, in spite of bomb-related injuries, are homogeneous in respect of variation of cancer risk with age with survivors without such injuries.

METHODS

Appropriate statistical models are derived and fitted to survivor data by maximum likelihood and the resultant statistics used to test the homogeneity assumption.

RESULTS

Significant differences were found between those with no injuries and those with multiple injuries and shown to be largely due to exposures before 10 or after 55 years of age having exceptionally high risks of late effects of radiation for survivors showing early effects, i.e. bomb-related injuries.

CONCLUSIONS

Certain accepted dogmas about the biology of radiation risks in humans, such as 'cancer is the only late effect of radiation' and 'leukaemia is uniquely radiogenic amongst cancers', may be significantly in error. These are discussed.

Consistency of swimming performance within and between competitions

PURPOSE

The consistency of performance between events impacts how athletes should specialize in events, how competitions should be structured, and how changes in performance affect an athlete's placing in an event. We have therefore determined the consistency of swimming performance in events within and between two national-level competitions.

METHODS

We used mixed linear modeling to analyze official performance times of 149 male and 162 female swimmers at a junior national championship, and of 117 male and 104 female swimmers at an open national championship 20 d later. The events differed in stroke (backstroke, breaststroke, butterfly, freestyle, and individual medley) or distance (50-1500 m).

RESULTS

Swimmers were most consistent in their performance for the same event between the two competitions (typical variation between competitions, 1.4%; 95% likely range of true value, 1.3-1.5%). They were less consistent between distances of a given stroke within each competition (1.7%; 1.5-1.9%) and least consistent between strokes for a given distance (2.7%; 2.3-3.1%). Variation in performance between the longest continuous freestyle distances (400, 800, and 1500 m) in the open competition was half that between widely spaced freestyle distances (50, 200, and 800 m). Faster swimmers were more consistent (1.1%; 0.9-1.4%) for the same event between competitions than slower swimmers (1.5%; 1.3-1.9%).

CONCLUSIONS

(a) Swimmers are stroke specialists rather than distance specialists; with the present set of events in competitions, they should concentrate training and competing on a particular stroke rather than a particular distance. (b) More swimmers would have a chance of winning a medal if events of a given stroke differed more widely in distance. (c) Factors that affect performance time by as little as 0.5% will affect the placing of a top junior swimmer.

General Gauge Independence of Diamagnetism plus Paramagnetism

With the use of the generalised multipolar gauge, a completely general proof is obtained for a result asserted by J. H. Van Vleck in 1932 but never fully proved by him. Specifically it is demonstrated that the matrix elements of the magnetic moment operator are independent of the origin of the vector potential for electromagnetic fields that are non-uniform in space and non-constant in time. A general survey of the principles of the quantum mechanics of solid state and molecular magnetism is also given to set the problem in its context. Based on the multipolar gauge, a simple conversion of the interaction Hamiltonian from the form of A.p to E.r plus higher order terms is demonstrated.

Evidence for lateral gene transfer between Archaea and bacteria from genome sequence of Thermotoga maritima

The 1,860,725-base-pair genome of Thermotoga maritima MSB8 contains 1,877 predicted coding regions, 1,014 (54%) of which have functional assignments and 863 (46%) of which are of unknown function. Genome analysis reveals numerous pathways involved in degradation of sugars and plant polysaccharides, and 108 genes that have orthologues only in the genomes of other thermophilic Eubacteria and Archaea. Of the Eubacteria sequenced to date, T. maritima has the highest percentage (24%) of genes that are most similar to archaeal genes. Eighty-one archaeal-like genes are clustered in 15 regions of the T. maritima genome that range in size from 4 to 20 kilobases. Conservation of gene order between T. maritima and Archaea in many of the clustered regions suggests that lateral gene transfer may have occurred between thermophilic Eubacteria and Archaea.

Fluid phase endocytosis within buccal mucosal cells of alcohol misusers

The structure of the oral mucosa is now well characterised, although studies on oral epithelial cell function have received less attention. The aims of this study were to see whether endocytosis could be demonstrated in cells from oral smears and if so, to assess the effect of chronic high alcohol intake on such uptake. Buccal mucosal smears were collected from 135 patients (91 non- or social drinkers, and 44 patients with harmful alcohol use). Name, age, sex, and alcohol history (for alcohol problem patients) were recorded. Cell suspensions were incubated in a solution of bovine serum albumin (BSA)-coated fluorescently labelled latex microspheres (0.02 micron diameter) in Ham's F-10 culture medium for 1 h at 37 degrees C as a marker of fluid phase endocytosis. Uptake of microspheres was confirmed by confocal microscopy, and mean endocytosed fluorescence levels determined by flow cytometry. A repeat smear from 11 of the alcohol patients was taken 9-14 days later. Endocytosis was significantly reduced in both male (P < 0.01) and female (P < 0.01) alcohol problem patients compared to controls. Units of alcohol consumed and cigarettes smoked per day did not show a dose-response correlation with endocytosis in the alcohol problem patients. Apparent abstinence from alcohol had no further effect on endocytic uptake at days 9-14. This study shows that normal oral squamous cells removed as buccal smears readily endocytose fluorescent microspheres and that this capacity can be affected by alcohol. Chronic high alcohol intake would appear to down regulate endocytosis in buccal cells even up to 14 days of abstinence. This may have implications for the pathogenesis of oral mucosal disorders in long-term users.

A-bomb survivors: reassessment of the radiation hazard

Newly released data from the Radiation Effects Research Foundation on the survivors of the Hiroshima and Nagasaki A-bombing allow a reassessment of radiation hazards. It appears that deaths from marrow damage (such as aplastic anaemia) continued after 1950. The Life Span Study cohort appears biased in favour of persons with high immunological competence, the result of infants and the elderly being more likely to die before 1950 than young adults. A study of survivors of in utero exposures suggests that embryos are more sensitive to the lethal effects of radiation than more mature foetuses. Current estimates of cancer risks from radiation may only apply to young adults with high immunological competence; young children and the elderly may be at greater risk.

Swimmers' compliance with training prescription

The purpose of this study was to determine how closely competitive swimmers complied with their coaches' prescriptions when training in squads. A training session early in the buildup phase of the season was observed for each of 24 coaches who had been randomized to two groups: an experimental, high-intensity, low-distance program (E) and a control (usual) program (C). Swim distances, rest durations, and swim durations for at least one set of prescribed repetitions (reps) were recorded for each of 47 swimmers (87 sets, 429 reps) in E and for 49 swimmers (79 sets, 402 reps) in C. The pace of each rep, expressed as percent of the swimmer's current personal best pace for the distance of the rep, represented observed intensity. There was almost perfect agreement between the prescribed and observed swim distances for the set of reps (Spearman r = 0.99 in both groups). Prescribed and observed rest intervals were also closely matched in E and C (Spearman r = 0.87 and 0.77 respectively). Four coaches in E and 10 coaches in C prescribed intensity subjectively as easy, moderate, hard, or race-pace; mean +/- SD observed intensities (%) for their swimmers were 79 +/- 6, 81 +/- 3, 91 +/- 2, and 93 +/- 5, respectively. The relationship between these coaches' subjective training prescription and individual swimmers' interpretations of these intensities was poor (Cohen's kappa = 0.39). Nine coaches in E prescribed intensity as percent of personal best pace. Although the mean prescribed and observed intensities for their swimmers were similar (89 +/- 4 and 90 +/- 7, respectively), the relationship between individual values was poor (Pearson r = 0.30). We conclude that swimmers complied with prescribed distances and rest intervals but were less effective in judging the intensity of swim training. We recommend that coaches monitor training intensity more closely.

Childhood cancer and parental use of tobacco: deaths from 1971 to 1976

Parental smoking data have been reabstracted from the interview records of the Oxford Survey of Childhood Cancers (deaths from 1971 to 1976). Reported smoking habits for the parents of 2587 children who died with cancer were compared with similar information for the parents of 2587 healthy controls (matched pairs analysis). Maternal daily consumption of cigarettes and paternal use of pipes or cigars were unimportant, but there was a statistically significant positive trend between paternal daily consumption of cigarettes and the risk of childhood cancer (P < 0.001). This association could not be explained by maternal smoking, social class, parental ages at the birth of the survey child, sibship position or obstetric radiography. Relations between maternal consumption of cigarettes and birth weights suggested that (maternal) smoking data were equally reliable for case and control subjects. About 14% of all childhood cancers in this series could be attributable to paternal smoking. These data were combined with smoking data from two previously published reports from the Oxford Survey (deaths from 1953 to 1955, deaths from 1977 to 1981) to obtain further information on risks for different types of cancer and different ages at onset of disease. Paternal cigarette smoking emerged as a potential risk factor both for the generality of childhood cancer and for all ages at onset.

Childhood cancer and parental use of tobacco: deaths from 1953 to 1955

Parental smoking data have been abstracted from the interview records of the case-control study that first indicated that pregnancy radiographs are a cause of childhood cancer (Oxford Survey of Childhood Cancers, deaths from 1953 to 1955). Reported smoking habits for the parents of 1549 children who died from cancer were compared with similar information for the parents of 1549 healthy controls (matched pairs analysis). There was a statistically significant positive trend between paternal daily consumption of tobacco and the risk of childhood cancer (P< 0.001). This association could not be explained by maternal smoking, social class, paternal or maternal age at the birth of the survey child, sibship position or obstetric radiography. About 15% of all childhood cancers in this series could be attributable to paternal smoking.

Relations between age at occupational exposure to ionising radiation and cancer risk

OBJECTIVES

To discover how the age when a given dose of ionising radiation is received (exposure age) affects the subsequent cancer risk, and whether the types of cancer caused by repeated exposure to small doses during adult life differ from naturally occurring cancers at that age.

METHOD

A nested case-control design with all possible controls in a cohort of nuclear workers, and a Mantel-Haenszel test (requiring only one degree of freedom) to discover whether there was any level of exposure age where the null hypothesis of no effects of radiation was rejected. This analysis was followed by inspection of how different types of cancers were related to the cancer risk.

RESULTS

For radiation received at least 15 years before a cancer death (to allow for cancer latency) evidence of a dose related risk was found which was largely the result of exposures during the last 10 years of working life (between 55 and 65 years of age). The relative frequency of site specific cancers showed no signs of being different for radiogenic and idiopathic cancers, and there was no evidence of the exceptionally strong association between radiation and leukaemia found in atomic bomb data and other high dose situations.

CONCLUSIONS

Sensitivity to carcinogenic effects of radiation increases progressively with age during adult life and, provided the dose is too small to produce many cell deaths, the ratio of leukaemias to solid tumours is no different for radiogenic and idiopathic cancers.

The Howard University Hospital Transplant and Dialysis Support Group: twenty years and going strong

This article discusses group therapy as part of a multidisciplinary approach to the management of the various psychological and physical rehabilitation concerns posed by kidney and liver transplant candidates and recipients at Howard University Hospital in Washington, DC. The group's history, format, intervention foci, and roles of clinicians and patients attending the group are described and evaluated. Given the relative paucity of research literature in this area, the authors offer recommendations for empirical evaluation of the benefits of multidisciplinary group psychotherapy in ameliorating physical and emotional suffering and prolonging life among transplant patients.

Factors affecting recognition of cancer risks of nuclear workers

OBJECTIVES

To discover whether direct estimates of the risks of cancer for nuclear workers agree with indirect estimates based on survivors of the atomic bomb; whether relations between age at exposure and risk of cancer are the same for workers and survivors, and whether dosimetry standards are sufficiently uniform to allow pooling of data from different nuclear industrial sites.

METHOD

Data from five nuclear sites in the United States were included in a cohort analysis that as well as controlling for all the usual factors also allowed for possible effects of three cancer modulating factors (exposure age, cancer latency, and year of exposure). This analysis was first applied to three distinct cohorts, and then to two sets of pooled data.

RESULTS

From each study cohort there was evidence of a risk of cancer related to dose, and evidence that the extra radiogenic cancers had the same overall histological manifestations as naturally occurring cancers and were largely the result of exposures after 50 years of age causing deaths after 70 years. There were, however, significant differences between the five sets of risk estimates.

CONCLUSIONS

Although the risks of cancer in nuclear workers were appreciably higher than estimates based on the cancer experiences of survivors of the atomic bomb, some uncertainties remained as there were non-uniform standards of dosimetry in the nuclear sites. The differences between nuclear workers and survivors of the atomic bomb were largely the result of relations between age at exposure and risk of cancer being totally different for workers and survivors and, in the occupational data, there were no signs of the special risks of leukaemia found in atomic bomb data and other studies of effects of high doses.