Control of posture with FES systems

One of the major obstacles in restoration of functional FES supported standing in paraplegia is the lack of knowledge of a suitable control strategy. The main issue is how to integrate the purposeful actions of the non-paralysed upper body when interacting with the environment while standing, and the actions of the artificial FES control system supporting the paralyzed lower extremities. In this paper we provide a review of our approach to solving this question, which focuses on three inter-related areas: investigations of the basic mechanisms of functional postural responses in neurologically intact subjects; re-training of the residual sensory-motor activities of the upper body in paralyzed individuals; and development of closed-loop FES control systems for support of the paralyzed joints.

Re-evaluating gender and smoking in Thunderbirds 35 years on

The rescreening of a cult children's puppet show made originally in the 1960s, showing the main characters smoking on occasion, raises questions over the appropriateness of such images for today's young viewers.

"Unwarranted survivals" and "anomalous deaths" from coronary heart disease: prospective survey of general population

OBJECTIVES

To assess survival in people who are at apparent high risk who do not develop coronary heart disease ("unwarranted survivals") and mortality in people at low risk who die from the disease ("anomalous deaths") and the extent to which these outcomes are explained by other, less visible, risk factors.

DESIGN

Prospective general population survey.

SETTING

Renfrew and Paisley, Scotland.

PARTICIPANTS

6068 men aged 45-64 years at screening in 1972-6, allocated to "visible" risk groups on the basis of body mass index and smoking.

MAIN OUTCOME MEASURES

Survival and death from coronary heart disease by age 70 years.

RESULTS

Visible risk was a good predictor of mortality: 13% (45) of men at low risk and 45% (86) of men at high risk had died by age 70 years. Of these deaths, 12 (4%) and 44 (23%), respectively, were from coronary heart disease. In the group at low visible risk other less visible risk factors accounted for increased risk in 83% (10/12) of men who died from coronary heart disease and 29% (84/292) of men who survived. In the high risk group 81/107 who survived (76%) and 19/44 (43%) who died from coronary heart disease had lower risk after other factors were considered. Different risk factors modified risk (beyond smoking and body mass index) in the two groups. Among men at low visible risk, poor respiratory function, diabetes, previous coronary heart disease, and socioeconomic deprivation modified risk. Among men at high visible risk, height and cholesterol concentration modified risk.

CONCLUSIONS

Differences in survival between these extreme risk groups are dramatic. Health promotion messages would be more credible if they discussed anomalies and the limits of prediction of coronary disease at an individual level.

Paclitaxel in the multimodality treatment for inflammatory breast carcinoma

BACKGROUND

Inflammatory breast carcinoma (IBC) is a rare but aggressive form of breast carcinoma. Anthracycline-based regimens represent the standard of treatment for IBC. Reports of significant clinical activity of paclitaxel in metastatic breast carcinoma led the authors to investigate the role of this drug in the management of IBC.

METHODS

Forty-four patients with IBC were enrolled between February 1994 and January 1998. The treatment plan consisted of induction chemotherapy (IC), mastectomy, adjuvant chemotherapy, and radiotherapy. Forty-two patients received IC with four cycles of fluorouracil, doxorubicin, and cyclophosphamide. If the clinical response was less than partial, patients were "crossed over" to paclitaxel before mastectomy. All patients received adjuvant paclitaxel. Patients unresectable after paclitaxel were offered high-dose chemotherapy with autologous peripheral blood progenitor cell support.

RESULTS

Thirty-four patients (81%) achieved an objective clinical remission; 3 patients (7%) achieved a clinical complete remission, 31 (74%) a partial remission. Six patients (14%) achieved pathologic complete remission. Sixteen patients were treated with paclitaxel, 7 of them (44%) were able to undergo mastectomy. Median time to progression (TTP) was 22 months. Median overall survival (OS) was 46 months. Concordance between clinical and pathologic response was documented in only 8 patients (24%). No differences in TTP and OS compared with a historical group of 178 IBC patients treated with anthracycline-based regimens.

CONCLUSIONS

Paclitaxel improves tumor resectability in anthracycline-refractory IBC. The impact of paclitaxel on the prognosis of IBC needs to be better evaluated in future trials using more dose-intensive schedules of administration. New imaging modalities may contribute to improve assessment of response to IC.

A cross-sectional study of IGF-I determinants in women

Evidence is accumulating that elevated circulating insulin-like growth factor I (IGF-I) is related to increased cancer risk. The identification of hormonal, reproductive and lifestyle characteristics influencing its synthesis and bioavailability is of particular interest. Data from 400 women, who served as controls in two case-control studies nested within the same prospective cohort study, were combined. IGF-I, IGF-binding proteins 1, 2 and 3 (IGFBP-1, -2, -3) and insulin were measured in serum samples from all subjects and cotinine in 186 samples. Age appears to be the most important determinant of total IGF-I levels in women. Anthropometric measures, such as body mass index (BMI) or waist-to-hip ratio (WHR) do not seem to influence total IGF-I concentrations in peripheral blood, but may modulate IGF-I bioavailability through insulin-dependent changes in IGFBP-1 and -2 concentrations. Age at menarche, phase of the menstrual cycle at blood draw, parity, menopause, past oral contraceptive or hormone replacement therapy use, and tobacco smoking do not appear to exert an independent effect on IGF-I and its binding proteins. There was some suggestion that regular physical activity may increase total IGF-I and that women with positive family history of breast cancer might have higher IGF-I levels than those without such diagnosis in their relatives.

The effects of rigid collar placement on intracranial and cerebral perfusion pressures

Rigid collars are routinely used to immobilise the cervical spine during early management of trauma victims until spinal injury is excluded. Spinal injuries commonly coexist in patients with severe head injury, and there is still uncertainty as to whether application of a rigid collar may adversely affect intracranial pressure. The aim of this study was to examine this effect by applying rigid collars to patients with traumatic head injury. The results showed a significant rise from the baseline intracranial pressure when the collars were applied (mean rise = 4.6 mmHg, p < 0.0001). The mean rise in intracranial pressure was greater in those patients with a baseline intracranial pressure > 15 mmHg compared to those with a baseline intracranial pressure < 15 mmHg (p < 0.05). Since there was no significant change in cardiorespiratory parameters during this time, venous compression in the neck seems a likely explanation for the effect observed. These findings suggest that in head-injured patients, rigid collars should be removed as soon as cervical spine injury has been excluded or, if this is delayed, an alternative method of spinal stabilisation considered.

Lay constructions of a family history of heart disease: potential for misunderstandings in the clinical encounter?

BACKGROUND

Family history is recognised as a risk factor for coronary heart disease (CHD) by epidemiologists, health professionals, and the public, and could act either as a spur or barrier to changing health behaviour. However, there has been no systematic investigation of which factors affect whether people regard themselves as having a family history of CHDor not.

METHODS

We used purposive sampling to select 61 men and women who were middle class or working class from a large cross-sectional survey. Half the respondents had indicated in this previous survey that they had heart disease in their family. The range of understanding of the meaning of having a family history was explored in detailed qualitative semistructured interviews.

FINDINGS

Perception of a family history of heart disease depended on knowledge of the health of family members, the number and closeness of relatives with heart conditions, the age of affected relatives, and the respondent's sex and social class. Men, particularly working-class men, required a greater number of close relatives to be affected to perceive that they had a family history. Even when respondents judged that heart disease ran in their family, they did not always perceive themselves as at increased risk because they felt different in crucial ways from affected relatives.

INTERPRETATION

The factors that people and epidemiologists judge as relevant to establish presence of a family history can differ. We suggest that these differences could lead to misunderstandings between doctor and patient, which could undermine advice on CHD risks and associated behavioural changes.

How accurately do adult sons and daughters report and perceive parental deaths from coronary disease ?

OBJECTIVES

To describe how adult sons and daughters report and perceive parental deaths from heart disease

DESIGN

Two generation family study.

SETTING

West of Scotland.

SUBJECTS

1040 sons and 1298 daughters aged 30-59 from 1477 families, whose fathers and mothers were aged 45-64 in 1972-76 and have been followed up for mortality over 20 years.

OUTCOME

Perception of a "family weakness" attributable to heart disease.

RESULTS

26% of sons and daughters had a parent who had died of coronary heart disease (CHD). The proportion was higher in older offspring (+18% per 10 year age difference) and in manual compared with non-manual groups (+37%). Eighty nine per cent of parental deaths from CHD were correctly reported by offspring. Only 23% of sons and 34% of daughters with at least one parent who had died of CHD considered that they had a family weakness attributable to heart disease. Perceptions of a family weakness were higher when one or both parents had died of CHD, when parental deaths occurred at a younger age, in daughters compared with sons and in offspring in non-manual compared with manual occupations.

CONCLUSIONS

Only a minority of sons and daughters with experience of a parent having died from CHD perceive this in terms of a family weakness attributable to heart disease. Although men in manual occupations are most likely to develop CHD, they are least likely to interpret a parental death from CHD in terms of a family weakness. Health professionals giving advice to patients on their familial risks need to be aware of the difference between clinical definitions and lay perceptions of a family history of heart disease.

Locoregional irradiation for inflammatory breast cancer: effectiveness of dose escalation in decreasing recurrence

PURPOSE

To evaluate the effect of radiation dose escalation on locoregional control, overall survival, and long-term complication in patients with inflammatory breast cancer.

PATIENTS AND METHODS

From September 1977 to December 1993, 115 patients with nonmetastatic inflammatory breast cancer were treated with curative intent at The University of Texas M. D. Anderson Cancer Center. The usual sequence of multimodal treatment consisted of induction FAC or FACVP chemotherapy, mastectomy (if the tumor was operable), further chemotherapy, and radiation therapy to the chest wall and draining lymphatics. Sixty-one patients treated from September 1977 to September 1985 received a maximal radiation dose of 60 Gy to the chest wall and 45-50 Gy to the regional lymph nodes, 22 treated once a day at 2 Gy per fraction, and 35 were treated b.i.d. (32 after mastectomy and all chemotherapy was completed, and 2 immediately after mastectomy; one patient had distant metastases discovered during b.i.d. irradiation, and treatment was stopped). Four additional patients received preoperative radiation with standard fractionation. Based on the analysis of the failure patterns of the patients, the dose was increased for the b.i.d. patients in the new series, with 51 Gy delivered to the chest wall and regional nodes, followed by a 15-Gy boost to the chest wall with electrons. From January 1986 to December 1993, 39 patients were treated b.i.d. to this higher dose after mastectomy and all the chemotherapy was completed; and 8 additional patients received preoperative irradiation with b.i.d. fractionation to 51 Gy. During this period, another 7 patients were treated using standard daily doses of 2 Gy per fraction to a total of 60 Gy, either because they had a complete response or minimal residual disease at mastectomy or because their work schedule did not permit the b.i.d. regimen. Comparison was made between the groups for locoregional control, disease-free and overall survival, and complication rates.

RESULTS

The median follow-up time was 5.7 years (range, 1.8-17.6 years). For the entire patient group, the 5- and 10-year local control rates were 73.2% and 67.1%, respectively. The 5- and 10-year disease-free survival rates were 32.0% and 28.8%, respectively, and the overall survival rates for the entire group were 40.5% and 31.3%, respectively. To evaluate the effectiveness of dose escalation, a specific comparison of patients who received b.i.d. radiation after mastectomy and completion of adjuvant chemotherapy was performed. There were 32 patients treated b.i.d. to 60 Gy in the old series versus 39 patients treated b.i.d. to 66 Gy in the new series. There was an significant improvement in the rate of locoregional control for the b.i.d. patients for the old vs. new series, from 57.8% to 84.3% and from 57.8% to 77.0% (p = 0.028) at 5 and 10 years, respectively. Chemotherapy regimens did not change significantly during this time period.Long-term complications of radiation, such as arm edema more than 3 cm (7 patients), rib fracture (10 patients), severe chest wall fibrosis (4 patients), and symptomatic pneumonitis (5 patients), were comparable in the two groups, indicating that the dose escalation did not result in increased morbidity. Significant differences in the rates of locoregional control (p = 0.03) and overall survival (p = 0.03), and a trend of better disease-free survival (p = 0.06) were also observed that favored the recently treated patients receiving the higher doses of irradiation.

CONCLUSION

Twice-daily postmastectomy radiation to a total of 66 Gy for patients with inflammatory breast cancer resulted in improved locoregional control, disease free survival, and overall survival, and was well tolerated.

Are perceptions of a family history of heart disease related to health-related attitudes and behaviour?

It has been argued that perceptions of familial tendencies to disease are common and important in decisions about health-related behaviours. Indeed, it has been suggested that the increased 'geneticization' of society may lead to an increased fatalism about health, which could undermine initiatives aimed at reducing coronary-prone behaviour. To date, much of the research on lay perceptions of inheritance has been based on people at high risk of particular genetic disorders or on qualitative research with small general population samples. Here we investigate perceptions of a family history of heart disease, using quantitative techniques, to test hypotheses about the relationship between a perceived family history (pFH), coronary 'candidacy' and adherence to health promotion advice which were raised by earlier anthropological work. We find that reported perceptions of a family history of heart disease are common, particularly amongst women in middle-age. In isolation a pFH is not related to current smoking; however, the odds of smoking are lower for those with a pFH of heart disease when account is also taken of other attitudinal factors (the 'salience' of heart disease and the strength of adherence to conventional coronary health promotion.

Social class, sex, and age differences in mucosal immunity in a large community sample

There have been very few reports addressing levels and distribution of commonly used PNI measures in large community samples. In this study, we report such data for secretion rates of secretory immunoglobulin A (sIgA), as determined from saliva samples taken from 1971 subjects interviewed as part of the West of Scotland Twenty-07 survey of health in West Central Scotland. Univariate analyses of demographic variables found lower sIgA and salivary flow to be significantly related to poorer social class, increased age, and being female. Smokers also had lower sIgA but not lower salivary flow. Multivariate analysis showed that demographic variables were significant predictors of sIgA independently of each other and assay variation. Adding smoking status to the equation confirmed it as an independent predictor and also indicated that social class differences in sIgA are partly explicable in terms of smoking status. In view of reported associations between sIgA levels and stress, its role as a first line of mucosal defense, and its relevance to health, these first results from a large survey are of interest. Further work is now needed to explore which factors, including psychosocial ones, may be contributing to subgroup differences.

Variation of recruitment nonlinearity and dynamic response of ankle plantarflexors

The ankle plantarflexor muscles of paraplegics may be trained to provide balance without support from the hands (in the laboratory environment) with the controller based on a two-block Hammerstein muscle model. This paper presents data on the variations of the recruitment curve block and linear dynamics block with electrode position, among various individuals and with fatigue. The tests were conducted in six groups: 'a' tests of a neurologically-intact subject were repeated on one day several times to record the effect of muscle fatigue; 'b' the same individual kept electrodes attached for a week and the muscle was identified every day; 'c' the same subject attached electrodes at marked positions every day for a week prior to identification; 'd' another normal attached electrodes at notionally the same positions over a period of one week; 'e' three normals and 'f' two paraplegics. Measurements were made with the Wobbler apparatus, in which the subject is supported upright in a standing posture. When comparing tests of fresh muscle every day, little difference was found between the nonlinear recruitment curves and linear dynamics of groups 'b' and 'c'. In fatigued muscle the dynamics were slower. When the electrode position was not carefully reproduced, and over a longer period, significant differences in nonlinearity appear in the curve shapes (group 'd') and a similar amount of variation occurs between normals, between paraplegics, and from normals to paraplegics. The paraplegic curves show wider deadbands. The effect of prolonged stimulation on normals is slight but on paraplegics it is significant.