"Post-GDM support would be really good for mothers": A qualitative interview study exploring how to support a healthy diet and physical activity after gestational diabetes

BACKGROUND

Women with a history of gestational diabetes mellitus (GDM) are at high risk of developing type 2 diabetes mellitus (T2DM). They are therefore recommended to follow a healthy diet and be physically active in order to reduce that risk. However, achieving and maintaining these behaviours in the postpartum period is challenging. This study sought to explore women's views on suggested practical approaches to achieve and maintain a healthy diet and physical activity to reduce T2DM risk.

METHODS

Semi-structured interviews with 20 participants in Cambridgeshire, UK were conducted at three to 48 months after GDM. The participants' current diet and physical activity, intentions for any changes, and views on potential interventions to help manage T2DM risk through these behaviours were discussed. Framework analysis was used to analyse the transcripts. The interview schedule, suggested interventions, and thematic framework were based on a recent systematic review.

RESULTS

Most of the participants wanted to eat more healthily and be more active. A third of the participants considered that postpartum support for these behaviours would be transformative, a third thought it would be beneficial, and a third did not want additional support. The majority agreed that more information about the impact of diet and physical activity on diabetes risk, support to exercise with others, and advice about eating healthily, exercising with a busy schedule, monitoring progress and sustaining changes would facilitate a healthy diet and physical activity. Four other suggested interventions received mixed responses. It would be acceptable for this support to be delivered throughout pregnancy and postpartum through a range of formats. Clinicians were seen to have important roles in giving or signposting to support.

CONCLUSIONS

Many women would appreciate more support to reduce their T2DM risk after GDM and believe that a variety of interventions to integrate changes into their daily lives would help them to sustain healthier lifestyles.

'Oh, I've got an appointment': A qualitative interview study exploring how to support attendance at diabetes screening after gestational diabetes

AIMS

To explore the views of women with a history of gestational diabetes mellitus (GDM) on suggested practical approaches to support diabetes screening attendance after GDM, which is recommended but poorly attended.

METHODS

We conducted semi-structured interviews with 20 participants in Cambridgeshire, UK who had been diagnosed with GDM and were 3-48 months postpartum. Interviews covered whether participants had been screened and why, plans for future screening and their views on potential interventions to facilitate attendance (at the first postpartum test and annual testing). Framework analysis was used to analyse the transcripts. The interview schedule, suggested interventions and thematic framework were based on a recent systematic review.

RESULTS

Sixteen participants had undergone screening since pregnancy, explaining that they had an appointment arranged and wanted reassurance that they did not have diabetes. The participants who had not been tested were not aware that it was recommended. Only 13 had planned to attend subsequent tests at the start of the interview. Eight themes to support future attendance were discussed. The majority of the participants agreed that changing the processes for arranging tests, offering choice in test location and combining appointments would facilitate attendance. Child-friendly clinics, more opportunities to understand GDM and the role of postpartum testing, stopping self-testing and increasing their GP's awareness of their pregnancy received inconsistent feedback. The nature of the test used did not appear to influence attendance.

CONCLUSIONS

The participants wanted to be screened for diabetes after GDM. We have identified interventions that could be relatively simply incorporated into routine practice to facilitate screening attendance, such as flexibility in the appointment location or time and sending invitations for tests.

Temporal variations in maternal treatment requirements and early neonatal outcomes in patients with gestational diabetes

AIMS

There is seasonal variation in the incidence of gestational diabetes (GDM) and delivery outcomes of affected patients. We assessed whether there was also evidence of temporal variation in maternal treatment requirements and early neonatal outcomes.

METHODS

We performed a retrospective analysis of women diagnosed with GDM (75 g oral glucose tolerance test, 0 h ≥ 5.1; 1 h ≥ 10.0; 2 h ≥ 8.5 mmol/L) in a UK tertiary obstetric centre (2015-2019) with a singleton infant. Data regarding demographic characteristics, total insulin requirements and neonatal outcomes were extracted from contemporaneous electronic medical records. Linear/logistic regression models using month of the year as a predictor of outcomes were used to assess annual variation.

RESULTS

In all, 791 women (50.6% receiving pharmacological treatment) and 790 neonates were included. The likelihood of requiring insulin treatment was highest in November (p < 0.05). The average total daily insulin dose was higher at peak (January) compared to average by 19 units/day (p < 0.05). There was no temporal variation in neonatal intensive care admission, or neonatal capillary blood glucose. However, rates of neonatal hypoglycaemia (defined as <2.6 mmol/L) were highest in December (40% above average; p < 0.05).

CONCLUSIONS

Women with GDM diagnosed in winter are more likely to require insulin treatment and to require higher insulin doses. Neonates born to winter-diagnosed mothers had a corresponding increased risk of neonatal hypoglycaemia. Maternal treatment requirements and neonatal outcomes of GDM vary significantly throughout the year, even in a relatively temperate climate.

The effect of sparging rate on transmembrane pressure and critical flux in an AnMBR

Anaerobic membrane bioreactors (AnMBRs) have been shown to be successful units for the treatment of low strength wastewaters, however, the issue of membrane fouling is still a major problem in terms of economic viability. Biogas sparging has been shown to reduce fouling substantially, and hence this study monitored the effect of biogas sparging rate on an AnMBR. The critical flux under a sparging rate of 6 l per minute (LPM) was found to be 11.8 l m(-2) h(-1) (LMH), however, membrane hysteresis was found to have an effect on the critical flux, and where the AnMBR had previously been operated with a 2 LPM sparging rate, the critical flux fell to 7.2 LMH. The existence of a "critical sparging rate" was also investigated under the condition that 'there exists a sparging rate beyond which any further decrease in sparging rate will cause a dramatic rise in TMP'. For an AnMBR operating at a flux of 7.2 LMH the critical sparging rate was found to be 4 LPM.

Migration inhibition produced by sodium periodate oxidation of the macrophage membrane, and reversal by sodium borohydride

Guinea pig peritoneal exudate cells were harvested 3 to 4 days after the intraperitoneal injection of Marcol oil. The washed cells were exposed to various concentrations of sodium periodate in phosphate-buffered saline (PBS) at pH 7.4 for 10 min at +4 degrees C. The cells were then used in the in vitro migration assay, and migration was consistently inhibited at concentrations from 10(-3) to 10(-5) M. The viability of the macrophages was not affected by this treatment. Sodium borohydride (10(-3) to 10(-5) M) in PBS for 10 min at pH 7.4 reversed the periodate effect. Experiments with purified macrophages showed that sodium periodate has a direct effect on macrophage function rather than an indirect effect via the potentiation of migration inhibition factor. In support of this, the in vitro spreading of macrophages on glass substrate for 1 h has been shown to be inhibited. This spreading inhibition can also be reversed by treatment with sodium borohydride. These results provide a new approach to understanding the biological significance and role of macrophage migration inhibition.

Rituximab for adolescents with haemophilia and high titre inhibitors

Neutralizing alloantibodies (inhibitors) to factor VIII or factor IX develop in approximately 25% of patients with haemophilia A and <3% of patients with haemophilia B treated with factor concentrate. Patients with high titre inhibitors, in whom immune tolerance therapy fails, have few treatment options. Targeted anti-B-cell therapy with rituximab (chimeric anti-CD20) has been useful in several antibody-mediated autoimmune states. Case reports of rituximab treatment in small numbers of haemophilia patients with inhibitors have been inconclusive. We describe three adolescent patients with severe haemophilia and inhibitors treated with four weekly doses of rituximab, 375 mg m(-2). Treatment with rituximab was effective in reducing the inhibitor titre in two of three patients. Rituximab may be beneficial for patients with severe haemophilia and inhibitors in whom standard therapies have failed, but larger prospective studies are required to determine safety, efficacy and predictors of success.

Intravascular brachytherapy of the coronary arteries

This is a review of the relatively recently developed field of intravascular brachytherapy of coronary arteries. It presents a brief overview of the discipline of coronary angioplasty describing the problem of restenosis and discusses the potential for ionizing radiation to overcome this problem. It examines the various methods that have been used to irradiate the coronary arteries comparing their advantages and disadvantages. Special consideration is given to seeds and wires in the artery, radioactive liquids in the angioplasty balloon and radioactive stents. Passing reference is made to a number of other methods that have also been proposed, but which are not commonly used to irradiate the coronary arteries at present. The dosimetry of each of the major techniques is discussed and the data from different laboratories compared. Specific consideration is given to the need for centring of the radioactive source and the factors affecting the selection of a dose prescription. A brief review of recent clinical trials is followed by an examination of possible future directions in this field including the use of intravascular ultrasound to improve dosimetry, the use of gas-filled balloons to enhance the penetration of beta-emitting sources and the use of gamma-emitting stents to overcome the problems associated with edge restenosis.

The shortened Study Process Questionnaire: an investigation of its structure and longitudinal stability using confirmatory factor analysis

BACKGROUND

The Study Process Questionnaire (SPQ) is a widely used measure of learning approach and was proposed to have three orientations: surface, deep, and achieving, each with an underlying motive and strategy.

AIMS

This study aimed to examine the factor structure and longitudinal stability over five to seven years of a modified shortened 18-item version of the SPQ.

SAMPLES

A total of 1349 medical students completed the shortened SPQ at application and in their final year of medical school. Three additional cohorts of students completed the shortened SPQ during their third and fourth year of medical school (sample size: 194, 203, 174).

METHOD

Confirmatory factor analysis was used to examine the dimensionality and longitudinal stability of the shortened SPQ.

RESULTS

Like the full 42-item version, the shortened SPQ has six subscales and the data are best fit by three second order shared indicator factors (surface, deep and achieving) and a single higher order composite deep-achieving factor. The longitudinal analysis found 26.8%, 26.3%, and 18.7% of the non-attenuated variance of the surface, deep and achieving factor scores in the final year is predicted from the shortened SPQ completed at application to medical school.

CONCLUSIONS

The shortened 18-item SPQ has the same six subscales as the full SPQ as well as three second order shared indicator factors (surface, deep, achieving) and one higher order deep-achieving factor similar to that suggested by Biggs (1987). The longitudinal analysis supports this hypothesis and suggests that these learning approaches are partly stable during medical school undergraduate training and partly modifiable under the influence of the educational environment.

Proposal for a gamma-emitting stent for the prevention and treatment of coronary artery restenosis

Radioactive stents have failed to prevent restenosis despite the demonstrated success of other radionuclide therapies using beta- or gamma-emitting radionuclides in the coronary arteries. This may be due to the rapid dose reduction at the end of the stent that occurs with a stent coated with 32P, which is a pure beta-emitter. A gamma-emitter will give a greater dose beyond the end of the stent and would therefore be expected to produce better results. However, it is essential that the gamma-emitter is not contaminated with beta particles of either sign nor with conversion electrons. This requirement generally demands the use of a high energy gamma-emitter, preferably with an energy greater than 500 keV. High energy gammas have other advantages, including a high radiation dose delivered per decay which reduces the total activity required and reduced dose near to the source due to electron disequilibrium. The ideal dose distribution is one that provides a uniform dose to the proliferating tissues and a reduced dose elsewhere. Although the target tissues are not well defined it is believed that the adventitia is the source of the proliferating cells. Hence the target tissue is between 0.5 and 2 mm depth into the artery. It is shown that 96Tc is a very suitable radionuclide for the production of radioactive stents giving a significantly greater dose compared with 32P both at depth and beyond the end of the stent for the same dose at the surface of the stent. Furthermore, 96Tc should be able to be made with a standard medical cyclotron and may be coated on to a stainless steel stent by a simple process that takes approximately 30 minutes to perform. Its half-life of 4.3 days will allow radioactive stents to be transported over significant distances and will result in a treatment time with a mean value of approximately 1 week. This will allow the rapid reestablishment of the endothelial layer which may be a further advantage of this radioactive stent.

The use of 188Re to treat in-stent re-stenosis of coronary arteries

A pilot study has been conducted in which coronary arteries subject to re-stenosis after angioplasty and stenting have been irradiated following further angioplasty. The method of irradiation has been to use radioactive 188Re in an angioplasty balloon. This paper considers all aspects of the procedure including elution of the rhenium from a tungsten/rhenium generator, its concentration, dispensing and safe delivery to the patient using specially designed equipment to reduce staff doses and radioactive spills. In the pilot study of 28 lesions in 26 patients only 1 was recorded as having angiographic re-stenosis in the treated region at 6 months although 4 other patients had edge re-stenosis. This represents less than 18% re-stenosis in a population that would have been expected to exhibit at least 50% re-stenosis at 6 months. A total of 72 patients have been treated either in the pilot study or a subsequent trial. In only one case has a minor spill of radioactivity occurred and in no case has the balloon burst. Radiation doses to staff are approximately 20 microSv per procedure and are therefore not of serious consequence. It is concluded that this procedure is safe, feasible and effective in reducing in-stent re-stenosis.

Neurological evidence in support of a specialized phonetic processing module

Event-related potentials (ERPs) were utilized to study brain activity while subjects listened to speech and nonspeech stimuli. The effect of duplex perception was exploited, in which listeners perceive formant transitions that are isolated as nonspeech "chirps," but perceive formant transitions that are embedded in synthetic syllables as unique linguistic events with no chirp-like sounds heard at all (Mattingly et al., 1971). Brain ERPs were recorded while subjects listened to and silently identified plain speech-only tokens, duplex tokens, and tone glides (perceived as "chirps" by listeners). A highly controlled set of stimuli was developed that represented equivalent speech and nonspeech stimulus tokens such that the differences were limited to a single acoustic parameter: amplitude. The acoustic elements were matched in terms of number and frequency of components. Results indicated that the neural activity in response to the stimuli was different for different stimulus types. Duplex tokens had significantly longer latencies than the pure speech tokens. The data are consistent with the contention of separate modules for phonetic and auditory stimuli.

Detection and quantification of intraperitoneal fluid using electrical impedance tomography

A prototype electrical impedance tomography system was evaluated prior to its use for the detection of intraperitoneal bleeding, with the assistance of patients undergoing continuous ambulatory peritoneal dialysis (CAPD). The system was sensitive enough to detect small amounts of dialysis fluid appearing in subtractive images over short time periods. Uniform sensitivity to blood appearing anywhere within the abdominal cavity was produced using a post-reconstructive filter that corrected for changes in apparent resistivity of anomalies with their radial position. The image parameter used as an indication of fluid quantity, the resistivity index, varied approximately linearly with the quantity of fluid added. A test of the system's response to the introduction of conductive fluid out of the electrode plane (when a blood-equivalent fluid was added to the stomach) found that the sensitivity of the system was about half that observed in the electrode plane. Breathing artifacts were found to upset quantitative monitoring of intraperitoneal bleeding, but only on time scales short compared with the fluid administration rate. Longer term breathing changes, such as those due to variations in the functional residual capacity of the lungs, should ultimately limit the sensitivity over long time periods.

Environmental sensitivities: prevalence of major symptoms in a referral center: the Nova Scotia Environmental Sensitivities Research Center Study

Although the phenomenon of environmental sensitivities (ES) has no clear etiology nor well-accepted pathophysiology, affected individuals experience symptoms that cause varying levels of dysfunction. Through a dedicated, government-funded research and treatment center, a detailed questionnaire covering 217 symptoms in 13 systems was mailed in 1997-1998 to 812 individuals referred to the center by physicians. A total of 385 (47%) questionnaires were returned, and data were analyzed on 351 individuals. Participants tended to be women (80%), middle-aged individuals (37% age 40-49 years), and those in higher educational groups (28% completed university), but there was wide variation in demographic variables. General symptoms such as difficulty concentrating, fatigue, forgetfulness, and irritability dominated the overall prevalence of symptoms since the start of their illness. Those related to irritation such as sneezing, itchy or burning eyes, and hoarseness or loss of voice were more common after exposure to environmental irritants. Ranking of symptoms using severity scores was consistent between men and women. Overall scores were higher in women, in participants who were separated or divorced, and in low-income groups. The type and consistency of symptoms experienced after exposure to triggering substances may not fit a purely psychogenic theory.

A study of pre-registration house officers' clinical skills

BACKGROUND

Little is known about the ability of pre-registration house officers (PRHOs) to perform basic clinical skills just prior to entering the medical register.

OBJECTIVES

To find out whether PRHOs have deficiencies in basic clinical skills and to determine if the PRHOs themselves or their consultants are aware of them.

METHOD

All 40 PRHOs at the Chelsea and Westminster and Whittington Hospitals were invited to undertake a 17 station OSCE of basic clinical skills. Each station was marked by one examiner completing an overall global score after completing an itemised checklist. An adequate station performance was the acquisition of a pass/borderline pass grade. Prior to the OSCE, a questionnaire was given to each PRHO asking them to rate their own abilities (on a 5-point scale) in the skills tested. A similar questionnaire was sent to the educational supervisors of each PRHO asking them to rate their house officer's ability in each of the same skills.

RESULTS

Twenty-two PRHOs participated. Each PRHO failed to perform adequately a mean of 2.4 OSCE stations (SD 1.8, range 1-8). There were no significant correlations between OSCE performance and either self- or educational supervisor ratings. The supervisor felt unable to give an opinion on PRHO abilities in 18% of the skills assessed.

DISCUSSION

This study suggests that PRHOs may have deficiencies in basic clinical skills at the time they enter the medical register. Neither the PRHOs themselves nor their consultants identified these deficiencies. A large regional study with sufficient power is required to explore the generalizability of these concerns in more detail.

The dosimetry for a coronary artery stent coated with radioactive 188Re and 32P

Radiation dose distributions have been calculated for 188Re and 32P activity on a coronary artery stent. The doses have been calculated both as a function of position along the stent and of depth into the artery wall. Comparisons of the dose from identical activities of 188Re and 32P on the stent show that the major differences arise from the different half-lives of the two activities. Coating the activity onto three surfaces of the stent rather than just the outside surface is found to reduce the dose by approximately 8 to 9%. Similarly, the effect of ignoring the attenuation in the stainless steel of the stent is to increase doses by 11 to 17%. Consideration is also given to the effect of the prolonged treatment times associated with a radioactive stent compared with the more common treatment over several minutes. It is shown that extended treatment may require between two and eight times the single dose to achieve the same effect depending on factors such as the radionuclide used, the dose required and the assumed cell survival curve. On the assumption that an instantaneous dose of 18 Gy at a depth of 1 mm into the artery would be required for successful prevention of neointimal hyperplasia, activities required for a stent coated with 188Re and 32P are tabulated.

Impact on medical students of incorporating GALS screen teaching into the medical school curriculum

OBJECTIVE

To assess the impact of GALS locomotor screen teaching to all 3rd year medical students, at a British medical school.

METHOD

In 1998, during their 3rd year, all students were taught the GALS screen in a one hour small group session. At the end of this year, 242 medical students undertook a 16 station Objective Structured Clinical Examination (OSCE). One station assessed the locomotor screening examination, while six stations assessed the examination of other systems. The students completed a five point likert scale, self rating their confidence in each of the skills assessed at this time. Pre-registration house officers (PRHOs) at two London hospitals were invited to undertake the same OSCE and self rating.

RESULTS

The students performed the locomotor screen well (mean station score 80%). Three body systems were examined better and one significantly worse (p<0.05). 22/40 PRHOs undertook the assessment. Compared with the students they examined the locomotor system (mean score 20%, p<0.001), but not other systems, less well. The PRHOs felt less confident (p<0.05) examining the locomotor system (mean rating 3.6/5) than the other systems (mean rating 4.6/5), while no significant difference in confidence ratings was seen for the students.

CONCLUSION

Students who are taught the GALS screen as part of the curriculum, perform it well in an end of year OSCE, as confidently as other systems, and to a higher standard than PRHOs. Further study is required to determine whether this benefit persists, overcoming the poor skills and confidence in locomotor examination of existing PRHOs, not previously taught a GALS screen.

Transmembrane versus soluble stem cell factor expression in human testis

The interaction between stem cell factor (SCF), a ligand produced by Sertoli cells, and its c-kit receptor on germ cells is necessary for successful spermatogenesis in animal models. SCF can be alternatively spliced into soluble and transmembrane forms, and it is the transmembrane form that is required for spermatogenesis in rodents. c-Kit receptors are also present on Leydig cells, and soluble SCF has been implicated in the regulation of testosterone production. This study had two goals: To test the hypothesis that the extent of germ cell production in human males is correlated with the expression of transmembrane SCF, and to examine the relationship between testosterone production and the expression of soluble SCF in humans. Reverse transcriptase polymerase chain reaction was used to determine the ratio of transmembrane-to-soluble SCF in testicular tissue. Clinical analysis, hormonal measurements, and histological methods were used to evaluate the causes of infertility and to seek correlations with the pattern of SCF expression. SCF was preferentially expressed as the transmembrane type in all testicular samples, regardless of the state of germ cell production. Furthermore, the percent of transmembrane SCF expression was independent of clinical and histopathological diagnosis (r(s) = 0.111, n = 28) and unrelated to the extent of spermatogenesis. This contrasts with rat models of testicular injury that exhibit a decreased proportion of transmembrane SCF with atrophy. A significant correlation (r(s) = 0.665, P < .02, n = 16) was found between testosterone levels and percent soluble SCF, which suggests that, in humans, there may be a regulatory interaction between soluble SCF and testosterone.

Defining the content for the objective structured clinical examination component of the professional and linguistic assessments board examination: development of a blueprint

INTRODUCTION

We describe the steps taken to develop an appropriate list of 'clinical problems' used to define the content of the objective structured clinical examination (OSCE) component of the Professional and Linguistic Assessments Board (PLAB) examination.

METHOD

A blueprint and list of 255 clinical problems was compiled by reviewing PLAB questions, published curricula of the UK Royal Colleges and other sources such as the General Medical Council's own guidelines. This list was sent to a random sample of 251 successful PLAB candidates who were asked to rate the clinical problems using a scale of 'seen frequently/seldom/never' and to 120 members of the accident and emergency (A&E) specialists' association who were asked to identify 'important' tasks. The list was further validated using activity data obtained for consecutive A&E attendances (934) and admissions (6130) at three hospitals.

RESULTS

After two mailings, 131/251 (52%) former PLAB candidates and 89/120 (74%) A&E specialists replied. All of the 255 clinical problems were seen by some former candidates and were felt to be important by some A&E specialists. Of the 255 problems, 40 were neither rated as important nor as seen frequently/seldom by over 50% of respondents. The 255 clinical problems covered a mean 94% consecutive A&E attendances and 97.6% reasons for hospital admission. The correlation between clinical problems that were frequently encountered and those felt to be important was rho=0.38 (P<0.01).

CONCLUSION

The clinical problems appear to be appropriate for defining the content of the PLAB OSCE. We suggest that our problem list is useful in that all the problems are seen by some senior house officers, are felt to be important by some A&E specialists and cover greater than or equal to 94% of the conditions for which patients both attend and are admitted from casualty. The correlation between clinical task importance and the frequency that they were seen was only moderate, partly reflecting the relative seriousness of some uncommon medical conditions, which should not be missed on clinical assessment. The content of the OSCE component of the PLAB examination is being reviewed in the light of the findings of this study. The limitations of the study are discussed.

Parenting among Hispanic and Anglo-American mothers with young children

The authors examined parenting practices and developmental expectations among 38 Hispanic and 38 Anglo-American mothers living in the United States. Mothers of children 3 to 5 years of age completed the Parent Behavior Checklist (R. A. Fox, 1994), a 100-item measure of parents' developmental expectations, discipline, and nurturing practices. In addition, the authors appraised the Hispanic mothers' acculturation and selected them for participation if their scores on an acculturation scale indicated (a) that their lifestyle was predominantly Hispanic and (b) that they had not been assimilated into the dominant culture. The 2 ethnic groups were also divided by socioeconomic status (SES). There were significant main effects for ethnicity and SES on the discipline and nurturing scores but not on the expectations scores. The Hispanic and higher SES mothers reported higher discipline and lower nurturing scores than did the Anglo-American and lower SES mothers. An unexpected finding was the tendency for higher SES Hispanic mothers to report more frequent use of discipline than the other 3 groups.

Can current models explain the lack of liver complications in Y-90 microsphere therapy?

Normal liver complications have not been observed in Y-90 microsphere therapy of hepatic tumors [selective internal radiation (SIR)], despite clinical studies reporting estimated absorbed doses to normal liver between 100 and 150 Gy. The purpose of the study was to see whether predictions of normal tissue complication probability (NTCP) models for liver based on clinical data from external beam therapy are consistent with clinical results of SIR. Liver NTCP was calculated using a parallel architecture model and normal liver dose-volume histograms that have been proposed for SIR. A parallel model including internal functional subunit structure is also proposed. Dose rate effects are incorporated. A criterion for comparing model calculations with clinical data is presented. For the parallel architecture model, the predicted NTCP is sensitive to the dose distribution in normal liver and to the model parameters, particularly the repair time. With reasonable assumptions about the microsphere distribution, the parallel model with parameters deduced from external beam therapy outcome analysis is consistent with the observed lack of liver complications. Inclusion of FSU structure widens the range of assumptions under which consistency is found. The parallel model can be consistent with the clinically observed lack of liver complications in SIR. More information about the activity distribution and the radiobiology of normal liver under conditions typical of microsphere therapy should be sought.

Intradermal testing for food and chemical sensitivities: a double-blind controlled study

BACKGROUND

Confirming adverse reactions to foods and chemicals is fundamental in providing a basis for diagnosis and treatment of patients with reported environmental sensitivities. Provocation-neutralization testing is widely used in this respect but has not been thoroughly evaluated, therefore remaining a controversial and unproven technique.

OBJECTIVE

This study investigated the validity of intradermal testing for evaluation of reported adverse reactions to a variety of incidents within the patient population at the Nova Scotia Environmental Health Centre.

METHODS

A total of 132 people who were referred to the Nova Scotia Environmental Health Centre, a dedicated government-funded research and treatment facility for suspected environmental sensitivities, were tested by the technique of provocation-neutralization by the guidelines set out by the American Academy of Environmental Medicine. A panel of 13 foods, 9 chemicals, and 4 placebos (normal saline solution) was evaluated in a double-blind, randomized study. Symptoms and skin reactions were recorded, and response rates were determined for all substances, including saline solution injections.

RESULTS

Seventy percent of the patients reported symptoms to 1 or more of the 4 saline solution injections. In comparison, 15% of patients experienced a skin reaction (wheal) to 1 or more injections of saline solution. Only 5% of individuals experienced a wheal to more than 1 saline solution injection, although 40% of the patients reported symptoms to more than 1 saline injection. Patients who experienced 1 or more reactions (wheal or symptoms) to saline solution were more reactive to injected allergens, on average reacting to 67% of active substances. Patients who experienced no reaction to the saline solution did experience a reaction to 48% of injected substances on average. Reaction by symptoms to foods, chemicals, and normal saline solution showed a random pattern, although wheal reactions showed a distinct pattern. Subsequent observations have indicated that experiencing no reaction to previous saline solution injections does not accurately predict response to saline solution in later testing. Some individuals who did not experience a reaction to saline solution in an initial screening later experienced a reaction to saline solution during further testing.

CONCLUSIONS

Provocation of symptoms in usual testing conditions is not a useful tool for discriminating between reactions to saline solution and reactions to specific chemicals or foods. Skin response alone may be a more reliable indicator and will require cross-validation with other tests, such as oral and inhalation challenges and comparison with a control population. Heightened sensitivity and chaotic responses may be a feature of chemical sensitivity. Meanwhile, the results of provocation-neutralization testing, using symptoms alone as an indicator of neutralization, should not be used as a basis for clinical intervention.

The effect of contrast medium and balloon shape on dosimetry for arterial irradiation with 188Re

The radiation dosimetry associated with the use of the beta particle emitter 188Re in an angioplasty balloon is investigated for the case when the balloon has an elliptical rather than circular cross section and when iodinated x-ray contrast medium is included inside the balloon. It is found that the elliptical cross section introduces significant dose corrections when the eccentricity of the ellipse is equal to or greater than 0.7. However, for cases where the artery is nearly circular in cross section, the corrections are likely to be small. As expected, the dose is reduced along the major axis of the ellipse and increased along the minor axis. The corrections are greatest at larger distances from the surface of the balloon. The effect on dose of contrast in the balloon is significant for 33% Omnipaque in saline. Since this is a typical concentration of contrast that is used for imaging the radiation-filled balloon, correction for the effects of contrast medium in the balloon should in general be applied. To enable corrections to be readily applied for other types and concentrations of contrast media, formulas have been derived that allow the dose correction to be calculated for a range of balloon diameters and at various distances from the surface of the balloon. To undertake this calculation, the elemental composition and density of the material in the balloon needs to be known.

The use of GAFchromic film to determine the absolute activity of beta emitters

A method of using GAFchromic film to determine the absolute activity of beta emitters by immersing the film in a bath of activity is described. This includes calculations of the effect of part of the radioactive solution being displaced by the film that is performing the measurement. Calculations have been performed for 90Y, 32P and 188Re. It is shown that for the film used in this study, this effect will cause a correction of the order of 15-20% for the three radionuclides studied. The results of the GAFchromic film measurement are compared with results obtained from liquid scintillation counting and from a commercial dose calibrator. It is shown that for 32P all methods were in reasonable agreement, but for 188Re, although the GAFchromic film and the liquid scintillation counting methods give similar results, the dose calibrator measurement differed by more than 20%. The GAFchromic film was also used to perform a direct measurement of the radiation dose at a distance of 0.5 mm from the surface of a cylindrical source of 188Re activity. This gave good agreement with the value of the dose predicted from theoretical calculations.

Characterizing knowledge deficits in phonological disorders

To aid the development of finer-grained measures of phonological competence within a representation-based approach to phonology, two aspects of nonsymbolic phonological knowledge (knowledge of the acoustic/perceptual space and of the articulatory/production space) were examined in 6 preschool-age children with phonological disorders and 6 typically developing age peers. To evaluate perceptual knowledge, gating and noise-center tasks were used. Children with phonological disorders recognized significantly fewer words than age peers on both tasks. To evaluate production knowledge, spectral and temporal measures were obtained for CV sequences involving both lingual and labial stop consonants. Group differences on this task (such as larger transition slope values from lingual consonants to vowels for children with phonological disorders) were also observed. These differerences were interpreted as indicating that the children with phonological disorders were less able to maneuver jaw and tongue body separately or that they used "ballistic" (i.e., less controlled) gestures from lingual consonants to vowels than their age peers. These results suggest that phonological knowledge is multifaceted, and that seemingly categorical deficits at one level can be linked to less robust representations at other levels.

Chronic exposure to hypergravity affects thyrotropin-releasing hormone levels in rat brainstem and cerebellum

In studies to determine the neurochemical mechanisms underlying adaptation to altered gravity we have investigated changes in neuropeptide levels in brainstem, cerebellum, hypothalamus, striatum, hippocampus, and cerebral cortex by radioimmunoassay. Fourteen days of hypergravity (hyperG) exposure resulted in significant increases in thyrotropin-releasing hormone (TRH) content of brainstem and cerebellum, but no changes in levels of other neuropeptides (beta-endorphin, cholecystokinin, met-enkephalin, somatostatin, and substance P) examined in these areas were found, nor were TRH levels significantly changed in any other brain regions investigated. The increase in TRH in brainstem and cerebellum was not seen in animals exposed only to the rotational component of centrifugation, suggesting that this increase was elicited by the alteration in the gravitational environment. The only other neuropeptide affected by chronic hyperG exposure was met-enkephalin, which was significantly decreased in the cerebral cortex. However, this alteration in met-enkephalin was found in both hyperG and rotation control animals and thus may be due to the rotational rather than the hyperG component of centrifugation. Thus it does not appear as if there is a generalized neuropeptide response to chronic hyperG following 2 weeks of exposure. Rather, there is an increase only of TRH and that occurs only in areas of the brain known to be heavily involved with vestibular inputs and motor control (both voluntary and autonomic). These results suggest that TRH may play a role in adaptation to altered gravity as it does in adaptation to altered vestibular input following labyrinthectomy, and in cerebellar and vestibular control of locomotion, as seen in studies of ataxia.

Hypergravity exposure decreases gamma-aminobutyric acid immunoreactivity in axon terminals contacting pyramidal cells in the rat somatosensory cortex: a quantitative immunocytochemical image analysis

Quantitative evaluation of gamma-aminobutyric acid immunoreactivity (GABA-IR) in the hindlimb representation of the rat somatosensory cortex after 14 days of exposure to hypergravity (hyper-G) was conducted by using computer-assisted image processing. The area of GABA-IR axosomatic terminals apposed to pyramidal cells of cortical layer V was reduced in rats exposed to hyper-G compared with control rats, which were exposed either to rotation alone or to vivarium conditions. Based on previous immunocytochemical and behavioral studies, we suggest that this reduction is due to changes in sensory feedback information from muscle receptors. Consequently, priorities for muscle recruitment are altered at the cortical level, and a new pattern of muscle activity is thus generated. It is proposed that the reduction observed in GABA-IR of the terminal area around pyramidal neurons is the immunocytochemical expression of changes in the activity of GABAergic cells that participate in reprogramming motor outputs to achieve effective movement control in response to alterations in the afferent information.

Parental discipline and behavior problems in young children

The relationship between parenting practices and behavior problems in very young children was investigated via the Parent Behavior Checklist (PBC; Fox, 1994). Results indicated that parents' use of verbal and corporal punishment was the strongest predictor of reported behavior problems, accounting for 20% of overall variance and 13% of unique variance. Results for parental nurturing and expectations were mixed and suggest an indirect effect. Several demographic variables were also predictive of behavior problems. Implications for Patterson's (1986) model of the development of antisocial behavior and for the use of parent assessment as a screening tool for preventive interventions are discussed.

Evaluating a brief parental-education program for parents of young children

The effectiveness of a brief parental-education program for 40 families with very young children was studied. Families were assigned to either a parental-education or waiting-list control group. The parental-education program included information and strategies drawn from developmental and cognitive psychology and social learning theory. Analysis showed that participating parents significantly reduced their use of corporal and verbal punishment, changed their parenting attitudes, and improved their perceptions of their children's behavior in comparison to the control group. Effects were maintained at six weeks follow-up. Results supported tailoring parental-education programs to the unique needs of participants.

Attention deficit hyperactivity disorder among adults with severe and profound mental retardation

The present study investigated the incidence of attention deficit hyperactivity disorder in a sample of 86 adults with severe to profound mental retardation. Participants were evaluated by supervisory staff using the diagnostic criteria from the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) and Conners' (1990) Hyperactivity Index. Using the most conservative measure, 15% of the sample met the diagnostic criteria. This measure was not influenced by the subjects' chronological age, adaptive age, IQ, or gender. Implications of this finding for continued research and practice were discussed.

Comprehensive geriatric assessment. Helping your elderly patients maintain functional well-being

In this article, three geriatricians describe an approach to comprehensive geriatric assessment that takes into account the multiple social and medical problems that affect the functional well-being of frail elderly patients. With a 45- to 90-minute time investment, physicians can obtain an inventory of the factors that threaten an elderly patient's independence and gain a fuller understanding of the patient's complex needs.

A simple phantom to locate the origin of MRI ghost artefacts

A simple pyramidal tube phantom has been designed to allow accurate location of a selected slice along the desired axis of a magnetic resonance scanner and to provide a check of the quality of slice selection. It is particularly helpful in locating the origin of any out-of-slice ghost artefacts. The geometry of the phantom allows the slice positions to be calculated readily.

Study of adaptation to altered gravity through systems analysis of motor control

Maintenance of posture and production of functional, coordinated movement demand integration of sensory feedback with spinal and supra-spinal circuitry to produce adaptive motor control in altered gravity (G). To investigate neuroplastic processes leading to optimal performance in altered G we have studied motor control in adult rats using a battery of motor function tests following chronic exposure to various treatments (hyper-G, hindlimb suspension, chemical distruction of hair cells, space flight). These treatments differentially affect muscle fibers, vestibular receptors, and behavioral compensations and, in consequence, differentially disrupt air righting, swimming, posture and gait. The time-course of recovery from these disruptions varies depending on the function tested and the duration and type of treatment. These studies, with others (e.g., D'Amelio et al. in this volume), indicate that adaptation to altered gravity involves alterations in multiple sensory-motor systems that change at different rates. We propose that the use of parallel studies under different altered G conditions will most efficiently lead to an understanding of the modifications in central (neural) and peripheral (sensory and neuromuscular) systems that underlie sensory-motor adaptation in active, intact individuals.

Effects of microgravity on muscle and cerebral cortex: a suggested interaction

The "slow" antigravity muscle adductor longus was studied in rats after 14 days of spaceflight (SF). The techniques employed included standard methods for light microscopy, neural cell adhesion molecule (N-CAM) immunocytochemistry and electron microscopy. Light and electron microscopy revealed myofiber atrophy, segmental necrosis and regenerative myofibers. Regenerative myofibers were N-CAM immunoreactive (N-CAM-IR). The neuromuscular junctions showed axon terminals with a decrease or absence of synaptic vesicles, degenerative changes, vacant axonal spaces and changes suggestive of axonal sprouting. No alterations of muscle spindles was seen either by light or electron microscopy. These observations suggest that muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight. In a separate study, GABA immunoreactivity (GABA-IR) was evaluated at the level of the hindlimb representation of the rat somatosensory cortex after 14 days of hindlimb unloading by tail suspension ("simulated" microgravity). A reduction in number of GABA-immunoreactive cells with respect to the control animals was observed in layer Va and Vb. GABA-IR terminals were also reduced in the same layers, particularly those terminals surrounding the soma and apical dendrites of pyramidal cells in layer Vb. On the basis of previous morphological and behavioral studies of the neuromuscular system after spaceflight and hindlimb suspension it is suggested that after limb unloading there are alterations of afferent signaling and feedback information from intramuscular receptors to the cerebral cortex due to modifications in the reflex organization of hindlimb muscle groups. We propose that the changes observed in GABA immunoreactivity of cells and terminals is an expression of changes in their modulatory activity to compensate for the alterations in the afferent information.

Dosimetry of beta emitting radionuclides for use in balloon angioplasty

The dose at varying distances from the surface of an infinite cylinder containing 90Y, 32P and 188Re respectively is calculated using published scaled point dose kernels for these three radionuclides. It is shown that all are suitable radionuclides for use in the irradiation of arteries subsequent to balloon angioplasty. All three may be used as a radioactive liquid in the angioplasty balloon, thereby simplifying the procedure and enabling a uniform radiation dose to be given to the arterial wall. It is however shown that there is a rapid reduction in dose with distance from the arterial wall which demands careful specification of the prescribed radiation dose. A similar rapid reduction with distance is also found with a central radioactive wire or with a radioactive stent containing the same radionuclides.

Parenting of young children by fathers in Mexico and the United States

In the present study, the parenting practices and developmental expectations were examined in a sample of 96 fathers from Mexico and the United States, all with children from 1 to 5 years of age. The selection of fathers from both countries was controlled for the family's socioeconomic status (SES) and for the age and gender of their children. The Parent Behavior Checklist, a 100-item rating scale was used to measure parents' developmental expectations and their discipline and nurturing practices. According to the results, Mexican and U.S. fathers did not differ significantly in their developmental expectations or parenting practices. In both countries, fathers from lower SES families were less nurturing and used more frequent discipline than fathers from higher SES families.

Light microscopic image analysis system to quantify immunoreactive terminal area apposed to nerve cells

The present report describes a desktop computer-based method for the quantitative assessment of the area occupied by immunoreactive terminals in close apposition to nerve cells in relation to the perimeter of the cell soma. This method is based on Fast Fourier Transform (FFT) routines incorporated in NIH-Image public domain software. Pyramidal cells of layer V of the somatosensory cortex outlined by GABA immunolabeled terminals were chosen for our analysis. A Leitz Diaplan light microscope was employed for the visualization of the sections. A Sierra Scientific Model 4030 CCD camera was used to capture the images into a Macintosh Centris 650 computer. After preprocessing, filtering was performed on the power spectrum in the frequency domain produced by the FFT operation. An inverse FFT with filter procedure was employed to restore the images to the spatial domain. Pasting of the original image to the transformed one using a Boolean logic operation called 'AND'ing produced an image with the terminals enhanced. This procedure allowed the creation of a binary image using a well-defined threshold of 128. Thus, the terminal area appears in black against a white background. This methodology provides an objective means of measurement of area by counting the total number of pixels occupied by immunoreactive terminals in light microscopic sections in which the difficulties of labeling intensity, size, shape and numerical density of terminals are avoided.

Human immunodeficiency virus infection in systemic lupus erythematosus

This report describes a female patient with systemic lupus erythematosus (SLE) who was infected with the human immunodeficiency virus (HIV). Using stored serum, the precise timing of HIV seroconversion was determined and the early effects of HIV infection on SLE examined. This infection resulted in clinical improvement and the disappearance of autoantibody production. A literature review of the association between HIV and SLE is provided.

The use of anisotropic data in 125I prostate implants

The report recently published by AAPM Task Group 43' (TG43) recommends the use of a two dimensional dose distribution function for the dosimetry associated with 125I, 192Ir and 103Pd sources. For commercial planning systems that cannot be readily adapted to use a two dimensional function, a point source approximation is provided. The dose distribution around an array of 125I seeds has been calculated using the two dimensional model and the point source approximation. Isodose distributions through selected planes and dose volume histograms of selected cubic volumes show that differences between the two models for this array are insignificant, particularly in view of the uncertainties associated with using the data which is provided by TG43 for the two dimensional anisotropy function.

Ligand linked assembly of Scapharca dimeric hemoglobin

The assembly of Scapharca dimeric hemoglobin as a function of ligation has been explored by analytical gel chromatography, sedimentation equilibrium, and oxygen binding experiments to test the proposal that its cooperativity is based on quaternary enhancement. This hypothesis predicts that the liganded form would be assembled more tightly into a dimer than the unliganded form and that dissociation would lead to lower oxygen affinity. Our experiments demonstrate that although the dimeric interface is quite tight in this hemoglobin, dissociation can be clearly detected in the liganded states with monomer to dimer association constants in the range of 10(8) M-1 for the CO-liganded state and lower association constants measured in the oxygenated state. In contrast, the deoxy dimer shows no detectable dissociation by analytical ultracentrifugation. Thus, the more highly hydrated deoxy interface of this dimer is also the more tightly assembled. Equilibrium oxygen binding experiments reveal an increase in oxygen affinity and decrease in cooperativity as the concentration is lowered (in the muM range). These experiments unambiguously refute the hypothesis of quaternary enhancement and indicate that, as in the case of human hemoglobin and other allosteric proteins, quaternary constraint underlies cooperativity in Scapharca dimeric hemoglobin.

Evaluating a training program for parental educators

This paper describes and evaluates a training program for parental educators to teach parenting classes for families with children 1 to 5 years of age. Six staff and parent volunteers from a family resource center participated. Evaluations of the training program showed improved knowledge and increased comfort in teaching parenting classes. Two graduates of the training program led a 10-week series of parenting classes. Parents in their class series (n = 9) significantly reduced their reported use of verbal and corporal punishment, increased their nurturing, and improved their perceptions of their children's behavior. These results were similar to those from a series of similar classes for 15 parents led by a university instructor. Results are discussed in terms of research needs for training qualified parental educators.

Parenting practices and expectations among Mexican mothers with young children

Parenting practices and developmental expectations were examined in a sample of 221 Mexican mothers with very young children living in Guadalajara, Jalisco. They completed a Spanish version of the Parent Behavior Checklist (PBC), a 100-item rating scale that measures parents' developmental expectations, discipline, and nurturing practices. The psychometric properties of the PBC for Mexican mothers, including test-retest reliabilities, were very similar to those found for mothers of young children in the United States. Younger Mexican mothers used more frequent discipline and less nurturing with their young children than older mothers did. Married mothers nurtured their children more than unmarried mothers; young, unmarried mothers nurtured their children the least. Lower nurturing scores were associated with lower education levels, and higher nurturing scores were associated with higher education levels. Mothers from higher socioeconomic levels held higher developmental expectations for their children, and they used less frequent discipline and more frequent nurturing practices than mothers from lower socioeconomic levels. These findings are consistent with those for mothers of young children in the United States.

Comparison of the stimulus properties of a pre- vs. a putative postsynaptic dose of quinpirole

Presynaptic D2-like receptors appear to mediate the stimulus properties of a low dose (0.05 mg/kg) of the D2-like agonist quinpirole (QUIN), because treatments decreasing dopamine (DA) release or blocking postsynaptic DA receptor activation produce QUIN-appropriate responding in a drug discrimination context, whereas treatments activating postsynaptic DA receptors evoke saline responding (28). This study examined the hypothesis that training to a presumably postsynaptic dose of QUIN (0.20 mg/kg) would produce the opposite pattern of effects. Using drug discrimination procedures, substitution for 0.05 mg/kg (28), but not 0.20 mg/kg QUIN, was produced by the D1 antagonist SCH23390, the catecholamine depleter alpha-methyl-paratyrosine and low doses of apomorphine (up to 0.25 mg/kg). The D2 agonist NPA substituted fully for 0.05 but only partially for 0.20 mg/kg QUIN. Cocaine and d-amphetamine (alone or with SCH 23390) substituted only minimally for either QUIN training dose. The putative D3 agonist 7-OH-DPAT engendered primarily saline responding when substituted for 0.20 QUIN. The 0.20 QUIN stimulus was antagonized by the D2 blocker haloperidol and partially blocked by the D1 antagonist SCH 23390. These data show a clear difference in the mediation of the stimulus properties of a low (0.05 mg/kg) vs. a high (0.20 mg/kg) dose of QUIN and are suggestive of a preferential postsynaptic D2 mediation of the 0.20 mg/kg QUIN dose.

Electrostatic charge on a plastic spacer device influences the delivery of salbutamol

The aim of this study was to determine whether electrostatic charge on a plastic spacer decreases the delivery of salbutamol from a pressurized metered-dose inhaler (pMDI) and, if so, to find an optimal and practical treatment to remove the charge. Ten single actuations from a salbutamol pMDI were drawn through different Volumatic spacers at a constant flow of 60 L.min-1. The efficacies of different methods of removing charge were tested, including detergent coating of the spacers. A multistage liquid impinger was used to determine the particle size distribution of the output of the pMDI through the Volumatic spacers. The electrostatic charge on the inner surface of the spacers was measured both quantitatively with an electrometer, and qualitatively by the attraction of a thin strip of cellulose membrane to the wall of the spacer. Each experiment was repeated four times. Ionic detergent coating of the spacers removed the charge for at least 24 h. This resulted in an increase of 55-70% in small particle (< 6.8 microns) delivery compared to delivery from new spacers with high charge. We have demonstrated that electrostatic charge plays a major role in the delivery of salbutamol through plastic spacers. Adequate treatment with ionic detergent removes the charge and improves drug delivery.

Expandable metal stents for non-malignant bronchial obstruction

An expandable metal stent was inserted to relieve bronchial obstruction following lobectomy for localised squamous carcinoma which had not been relieved by bronchoplasty with a Goretex flap. This resulted in substantial improvement in lung function and exercise tolerance for nine months, following which severe inflammation around the stents required residual pneumonectomy.