Radiation dose to staff from medical X-ray scatter in the orthopaedic theatre

PURPOSE

Given the growing demand for intraoperative imaging, there is increased concern for radiation dose for orthopaedic surgical staff. This study sought to determine the distribution of scatter radiation from fluoroscopic imaging in the orthopaedic surgical environment, with particular emphasis on the positions of personnel and the type of orthopaedic surgery performed.

METHODS

A radiation survey detector was deployed at various angles and distances around an anthropomorphic phantom. The scatter dose rate in microsieverts per hour (µSv/h) was recorded using consistent exposure parameters for five common surgical procedures. A C-arm unit produced radiation for the hip arthroscopy, hip replacement and knee simulations, whilst a mini C-arm unit produced fluoroscopy for the foot and hand simulations.

RESULTS

Readings were tabulated, and coloured heatmaps were generated from scatter measurements for each of the five procedures. Positions corresponding to the typical location of the surgical staff (surgeon, surgical assistant, anaesthetist, instrument (scrub) nurse, circulation (scout) nurse and anaesthetic nurse) were superimposed on heatmaps. The surgeon's proximity to the radiation source meant this position experienced the greatest amount of radiation in all five surgical procedures. Mini C-arm doses were considered low in all procedures for positions, with and without lead protection.

CONCLUSION

This investigation demonstrated the distribution of scattered radiation dose experienced at different positions within the orthopaedic surgical theatre. It reinforces the importance of staff increasing their distance from the primary beam where possible, reducing exposure time and increasing shielding with lead protection.

Barriers to Implementation of Breast Cancer Risk Assessment: The Health Care Team Perspective

PURPOSE

To assess health care professionals' perceptions of barriers to the utilization of breast cancer risk assessment tools in the public health setting through a series of one-on-one interviews with health care team members.

METHODS

We conducted a cross-sectional qualitative study consisting of one-on-one semistructured telephone interviews with health care team members in the public health setting in the state of Tennessee between May 2020 and October 2020. An iterative inductive-deductive approach was used for qualitative analysis of interview data, resulting in the development of a conceptual framework to depict influences of provider behavior in the utilization of breast cancer risk assessment.

RESULTS

A total of 24 interviews were completed, and a framework of influences of provider behavior in the utilization of breast cancer risk assessment was developed. Participants identified barriers to the utilization of breast cancer risk assessment (knowledge and understanding of risk assessment tools, workflow challenges, and availability of personnel); patient-level barriers as perceived by health care team members (psychological, economic, educational, and environmental); and strategies to increase the utilization of breast cancer risk assessment at the provider level (leadership buy-in, training, supportive policies, and incentives) and patient level (improved communication and better understanding of patients' perceived cancer risk and severity of cancer).

CONCLUSIONS

Understanding barriers to implementation of breast cancer risk assessment and strategies to overcome these barriers as perceived by health care team members offers an opportunity to improve implementation of risk assessment and to identify a racially, geographically, and socioeconomically diverse population of young women at high risk for breast cancer.

Black Women's Perspectives on Breast Cancer Risk Assessment

PURPOSE

The aim of this study was to gather the perspectives of Black women on breast cancer risk assessment through a series of one-on-one interviews.

METHODS

The authors conducted a cross-sectional qualitative study consisting of one-on-one semistructured telephone interviews with Black women in Tennessee between September 2020 and November 2020. Guided by the Health Belief Model, qualitative analysis of interview data was performed in an iterative inductive and deductive approach and resulted in the development of a conceptual framework to depict influences on a woman's decision to engage with breast cancer risk assessment.

RESULTS

A total of 37 interviews were completed, and a framework of influences on a woman's decision to engage in breast cancer risk assessment was developed. Study participants identified several emerging themes regarding women's perspectives on breast cancer risk assessment and potential influences on women's decisions to engage with risk assessment. Much of women's decision context was based on risk appraisal (perceived severity of cancer and susceptibility of cancer), emotions (fear and trust), and perceived risks and benefits of having risk assessment. The decision was further influenced by modifiers such as communication, the risk assessment protocol, access to health care, knowledge, and health status. Perceived challenges to follow-up if identified as high risk also influenced women's decisions to pursue risk assessment.

CONCLUSIONS

Black women in this study identified several barriers to engagement with breast cancer risk assessment. Efforts to overcome these barriers and increase the use of breast cancer risk assessment can potentially serve as a catalyst to address existing breast cancer disparities. Continued work is needed to develop patient-centric strategies to overcome identified barriers.

Corrigendum to '' [BJA Education 22 (2022) 396-401]

[This corrects the article DOI: 10.1016/j.bjae.2022.06.003.].

0174 Examining Circadian Disadvantages in the National Basketball Association’s Playoffs

Introduction

Prior research on travel in the National Basketball Association’s (NBA) regular season has shown that teams journeying west relative to their home base face circadian disadvantages for evening games, while those traveling east have advantages. The current study extends previous research by examining these effects within the NBA playoffs. We hypothesized that teams would have a greater circadian advantage during eastward compared to westward travel.

Methods

In 2013, the NBA implemented a 7-game series playoff structure, in which teams play an alternating home/away 2-2-1-1-1 format. Data for all 499 postseason games played during the 2013–14 to 2018–2019 seasons were collected from Basketball-Reference and FiveThirtyEight. We investigated the impact of direction of travel based on home base city (same time zone, westward, eastward) and time zones traveled on game outcomes, Elo rating differences (i.e., a team quality metric based on wins and losses), win probability, and team scoring.

Results

Teams had lower win probabilities following 3-hour westward than same time zone and all eastward travel, while 3-hour eastward travel related to higher probabilities of winning compared to same time and all westward travel (p < .001, d > .95). Teams travelling westward with 2-hour time changes lost significantly more games than those experiencing 1-hour westward (p = .04, OR = 2.45), 1-hour eastward (p = .05, OR = 2.34), and 3-hour eastward changes (p = .02, OR = 4.68). Scoring was significantly higher following eastward travel compared to both westward (p = .001, d = 0.60) and same time zone travel (p = .003, d = 0.44). There were no differences in team quality based on direction of travel or number of time zones traveled, and game outcomes based on overall direction of travel (p > .05).

Conclusion

Direction and magnitude of travel were related to win probability, team scoring, and game outcomes, whereby teams travelling eastward and within the same time zone gained an advantage over those travelling westward. Adjustment to travel and time changes appear to influence in-game performances and outcomes in the NBA playoffs.

Support

None

The Health Assessment Questionnaire Disability Index is a valid measure of physical function in gout

OBJECTIVE

There are no disability instruments that have specifically been validated for gout. The aim of this study was to determine the construct validity of the Health Assessment Questionnaire Disability Index (HAQ-DI) in gout and the internal validity using Rasch analysis.

METHODS

An observational cohort study of two groups of clinic patients with gout (n=20, n=53), in which clinical and functional measures were correlated with HAQ-DI scores. Rasch analysis was used to determine the internal validity of summated scores as a measure of physical disability.

RESULTS

The HAQ-DI items fitted a Rasch measurement model, confirming internal validity of the scale, although there was evidence of disordered thresholds and rescoring items as a 3-option response rather than a 4-option response improved model fit and resolved the disordered thresholds. HAQ-DI scores showed a bimodal distribution and evidence of floor effects. Clinical indices correlated highly with HAQ-DI scores in gout patients, particularly other measures of physical function. A strong relationship between days of sick leave and HAQ-DI was observed in gout patients (r2=0.44, p<0.001).

CONCLUSIONS

It is concluded that HAQ-DI has good construct and internal validity in gout but a modified scoring approach better fits a Rasch model.

Modern chemotherapy management of recurrent ovarian cancer: a multicentre study

AIMS

The natural history of ovarian cancer has changed over the last 10 years due to more effective drug treatments. The aim of this multicentre audit of the management of recurrent ovarian cancer was to examine the usage of newer drugs in light of the publication of National Institute of Clinical Excellence guidance.

MATERIALS AND METHODS

All patients presenting with a first or subsequent relapse of ovarian cancer between August 2001 and February 2003 in nine UK National Health Service centres were identified. Data were recorded retrospectively and prospectively from point of entry into the study and included the modality of primary cancer treatment, the treatment of each subsequent relapse and outcome.

RESULTS

In total, 245 evaluable patients were entered on to the database. The mean age was 62 years. All patients received a platinum-based chemotherapy regimen as first-line treatment. One hundred and fifty-five patients (63%) went on to receive third-line chemotherapy and 82 (34%) received fourth-line chemotherapy. The median survival from first relapse was estimated to be in excess of 12 months from our data. The efficacies of the chemotherapy agents used are comparable with the results of published phase III trials.

CONCLUSION

This study shows that multicentre audit is feasible and provides useful information on current clinical practice on which to base future research.

A standard approach to measurement uncertainties for scientists and engineers in medicine

The critical nature of health care demands high performance levels from medical equipment. To ensure these performance levels are maintained, medical physicists and biomedical engineers conduct a range of measurements on equipment during acceptance testing and on-going quality assurance programs. Wherever there are measurements, there are measurement uncertainties with potential conflicts between the measurements made by installers, owners and occasionally regulators. Prior to 1993, various methods were used to calculate and report measurement uncertainties. In 1993, the International Organization for Standardization published the Guide to the Expression of Uncertainty in Measurement (GUM). The document was jointly published with six international organizations principally involved in measurements and standards. The GUM is regarded as an international benchmark on how measurement uncertainty should be calculated and reported. Despite the critical nature of these measurements, there has not been widespread use of the GUM by medical physicists and biomedical engineers. This may be due to the complexity of the GUM. Some organisations have published guidance on the GUM tailored to specific measurement disciplines. This paper presents the philosophy behind the GUM, and demonstrates, with a medical physics measurement example, how the GUM recommends uncertainties be calculated and reported.

Aftercare attendance and post-treatment functioning of severely substance dependent residential treatment clients

The present study evaluated the impact of a structured aftercare programme following residential treatment for severe alcohol and/or heroin dependent clients. Over 17 months, 77 participants were recruited to the study and allocated randomly to either a structured aftercare (SA) programme or to unstructured aftercare (UA) of crisis counselling on request. Independent clinicians interviewed participants and collaterals, at 4-month (median) intervals, for 12 months following residential treatment. SA compared to UA was associated with a fourfold increase in aftercare attendance and one-third the rate of uncontrolled principal substance use at follow-up. Participants who attended either type of aftercare relapsed a median of 134 days later than those who attended no aftercare. Overall, 23% of monitored participants remained abstinent throughout, 21% maintained controlled substance use and 56% relapsed, within a median of 36 days following residential treatment. The only significant predictor of days to relapse, controlling for age, was pretreatment use of additional substances. Participants with pretreatment additional substance use relapsed a median of 192 days earlier than those who had used no other substances. The degree of agreement between participant self-reports and collateral reports was fair-to-moderate and moderate among collaterals. Intention-to-treat analyses revealed significant and clinically meaningful reductions in substance use in this sample of severely dependent residential treatment clients. The generalizability of these results is limited because of significant differences in age and presenting substance between the study sample and other clients admitted to the service during the study. This latter group of younger, male, heroin-dependent clients with polydrug use who refuse opioid pharmacotherapy, are more likely to drop out of treatment or relapse early following treatment and continue to present a challenge to treatment services.

Premature rupture of the membranes: an evidence-based approach to clinical care

Management of the patient with premature rupture of membranes is a relatively common but often perplexing problem frequently faced by the obstetrician. Despite the recent advances in perinatal care, premature membrane rupture, especially in the preterm patient, remains a potentially serious complication with important maternal and fetal implications. This review will address the important questions concerning the management of premature rupture of membranes and will attempt to provide comprehensive answers as they appear in the medical literature.

Obstetrician-gynecologists' knowledge and training about antenatal corticosteroids

OBJECTIVE

To characterize the clinical decisions, knowledge, opinions, and education of obstetricians and gynecologists about antenatal corticosteroids.

METHODS

Questionnaires mailed to 1020 ACOG Fellows included items on demographics, knowledge, clinical practice patterns, and educational background regarding antenatal corticosteroids.

RESULTS

The survey response rate was 47.8%. Almost all respondents (94%) reported administering antenatal corticosteroids, with reduction of respiratory distress syndrome (82%) as the primary reason for antenatal corticosteroid administration. Most (59.2%) were unaware of newly recognized associations between multiple administrations of corticosteroids and fetal growth restriction. In hypothetical clinical situations, responses by physicians who completed their residency training before 1970 indicated less likelihood to administer corticosteroids when administration is relatively indicated per National Institutes of Health (NIH) and ACOG guidelines than those trained later (P <.001). Only 8% of the entire sample rated their knowledge of antenatal corticosteroids as comprehensive; most (68%) rated it as adequate. Respondents rated residency training as a much better source of antenatal corticosteroid knowledge than medical school.

CONCLUSION

Most obstetrician-gynecologists reported using antenatal corticosteroids; however, in general, many were not aware of more recent information regarding potential risks. This survey suggests that a multipronged educational approach is warranted to update obstetrician-gynecologists about antenatal corticosteroids.

Effects of transmyocardial laser revascularization by using a prototype pulsed CO2 laser on contractility and perfusion of chronically ischemic myocardium in a porcine model

The purpose of this study was to test a new prototype pulsed CO2 laser to be used for transmyocardial laser revascularization (TMR). We wanted to determine whether it can reduce thermal damage and mitigate induced ischemia with improvement in contractile reserve of the heart as evidenced by contrast echocardiography at rest and under dobutamine stress. TMR is an emerging surgical strategy for treatment of myocardial ischemia not amenable to conventional percutaneous or surgical revascularization. Eleven pigs underwent ameroid occluder placement at the origin of the circumflex coronary artery. Six weeks later, occlusion of the circumflex coronary artery was documented. TMR was then carried out on 10 pigs by using a prototype pulsed CO2 laser that delivered 8-12 joules in 1.5 ms with a spot size of 1 mm. Six weeks after TMR, the pigs were restudied. The animals developed significant ischemia after 6 weeks of ameroid occlusion, at rest (p = 0.01) and at peak stress (p = 0.004). Wall motion for the ischemic segments improved significantly 6 weeks after TMR at peak stress (p = 0.02). TMR results in an improvement in wall motion in our model of chronic ischemia and improves wall motion score index more during induced stress than at rest.

A randomized phase II study of SRL172 (Mycobacterium vaccae) combined with chemotherapy in patients with advanced inoperable non-small-cell lung cancer and mesothelioma

Mycobacterial preparations have been used with limited success against cancer apart from superficial bladder cancer. Recently, a therapeutic vaccine derived from Mycobacterium vaccae has been given to patients with prostate cancer and melanoma indicating a possible beneficial effect on disease activity in such patients. We have recently initiated a series of randomized studies to test the feasibility and toxicity of combining a preparation of heat-killed Mycobacterium vaccae (designated SRL172) with a multidrug chemotherapy regimen to treat patients with inoperable non-small cell lung cancer (NSCLC) and mesothelioma. 28 evaluable patients with previously untreated symptomatic NSCLC and mesothelioma were randomized to receive either 3 weekly intravenous combination chemotherapy alone, or chemotherapy given with monthly intra-dermal injections of SRL172. Safety and tolerability were scored by common toxicity criteria and efficacy was evaluated by survival of patients and by tumour response assessed by CT scanning. The toxicity of chemotherapy was similar in the two groups. SRL172 caused mild inflammation at the injection site. In the group of patients randomized to receive chemotherapy combined with SRL172, there was a trend towards improved response rate (54% vs. 33%) with more patients in the combined arm receiving radical surgery and radiotherapy, improved median survival (9.7 months vs. 7.5 months) and improved 1 year survival (42% vs. 18%). SRL172 appeared to improve sleep (P = 0.08) and improved appetite (P = 0.01). There was no detectable change in serum cytokine levels for gamma-interferon and TNF-alpha before and after treatment. In patients with NSCLC and mesothelioma, there may be a beneficial interaction when chemotherapy is administered in combination with SRL172. Confirmation of this effect and further investigation is underway in a randomized phase III trial and in laboratory models.

Femur length and trisomy 21: impact of gestational age on screening efficiency

OBJECTIVE

This study assesses two methods used to define relatively short femur in screening for trisomy 21 and examines changes in performance of screening with gestational age.

DESIGN

Retrospective analysis of data on menstrual age, femur length (FL) and biparietal diameter (BPD) in 49 trisomy 21 pregnancies and 6069 normal controls. Reference ranges were derived for BPD/FL versus menstrual age and for FL versus BPD. Two methods of defining short femur (BPD/FL and observed-to-expected FL ratio) were examined for false-positive rates and detection rates for trisomy 21 at different gestational ages.

RESULTS

In the control group the BPD/FL ratio and its standard deviation decreased with menstrual age. Trisomy 21 was associated with a significantly higher BPD/FL ratio (P < 0.001) and the deviation increased significantly with menstrual age (P < 0.05). Eleven percent of 28 fetuses examined at 15-17 weeks had a BPD/FL above the 95th centile compared with 24% of 21 fetuses examined at 18-20 weeks (P = 0.40). The median observed-to-expected FL ratio in the control group was 1.0 throughout the gestational age range but the standard deviation decreased significantly with menstrual age (P < 0.01). Trisomy 21 was associated with a significantly reduced observed-to-expected FL ratio (P < 0.001) and the deviation increased significantly with menstrual age (P < 0.05). A fixed cut-off of 0.91 for observed-to-expected FL ratio provided a false-positive rate of 12% at 15-17 weeks compared with 6% at 18-20 weeks of gestation (P < 0.001) with detection rates of 29 and 38%, respectively (P = 0.73).

CONCLUSION

Irrespective of the definition used to define the condition, relatively short femur is a poor marker for trisomy 21 particularly when the assessment takes place before 18 weeks of gestation.

Periodontal status of diabetic and non-diabetic men: effects of smoking, glycemic control, and socioeconomic factors

Periodontal disease is more prevalent and more severe in diabetic than in non-diabetic individuals but the magnitude of this increase is still being debated. This prospective, cross-sectional study compared the periodontal status of 118 diabetic men and 115 age-matched non-diabetic men. Plaque and gingival indices, bleeding scores, probing depth, loss of attachment, and number of missing teeth were measured in a blinded manner. Smoking status, glycemic control, socioeconomic status, and previous dental care were also assessed. These parameters were significantly higher in diabetic than non-diabetic men: plaque index, P < 0.0001; gingival index, P < 0.0002; bleeding score, P < 0.0001; probing depth, P = 0.0059; loss of attachment, P < 0.0001; and missing teeth, P < 0.005. These parameters were significantly higher in smokers than non-smokers: gingival index, probing depth, and loss of attachment. The duration of diabetes was not significantly related to the periodontal measures. Glycemic control as assessed by fasting plasma glucose and glycohemoglobin values was not significantly correlated to periodontal status. These studies indicate, for this study group, that diabetes significantly affects all measured parameters of periodontal status.

The outcome of macrosomic infants weighing at least 4500 grams: Los Angeles County + University of Southern California experience

OBJECTIVE

To describe the maternal and neonatal outcome of macrosomic infants weighing at least 4500 g.

METHODS

Maternal and neonatal records of infants with birth weights of at least 4500 g were identified during 1991. Outcome variables included the mode of delivery and incidence of maternal and perinatal complications.

RESULTS

The study sample consisted of 227 infant and mother pairs. Mean (+/- standard deviation) birth weight was 4706 +/- 219 g. A trial of labor was allowed in 192 women, and elective cesarean delivery was performed in 35 patients. The overall cesarean rate, including elective cesarean delivery and failed trial of labor, was 30.8% (70 of 227). Of those undergoing a trial of labor, 82% (157) delivered vaginally. Shoulder dystocia occurred 29 times, for an incidence of 18.5% in vaginal deliveries for macrosomia. There were seven cases each of Erb palsy and clavicular fracture, and one humeral fracture. By 2 months of age, all affected infants were without permanent sequelae. There was no birth asphyxia or perinatal mortality related to delivery for macrosomia. Maternal complications included increased risk of lacerations requiring repair (especially third- or fourth-degree lacerations) when vaginal delivery was complicated by shoulder dystocia (relative risk [RR] 5.4, 95% confidence interval [CI] 3.1-9.4). There was no statistically significant difference with respect to hemorrhage or hospital stay for women who had a vaginal delivery (with or without shoulder dystocia) compared with women who had a cesarean delivery. However, infectious morbidity increased significantly in those patients who underwent a cesarean after a trial of labor compared with women who had a vaginal delivery (RR 7.1, 95% CI 3.9-13.1) or elective cesarean birth (RR 5.4, 95% CI 3.1-9.4). Ninety-one percent of patients undergoing elective cesarean delivery had no complications.

CONCLUSION

Vaginal delivery is a reasonable alternative to elective cesarean for infants with estimated birth weights of at least 4500 g, and a trial of labor can be offered.

An identified glutamatergic interneuron patterns feeding motor activity via both excitation and inhibition

1. Previously we demonstrated that glutamate is an important neurotransmitter in the CNS of Helisoma. Exogenous glutamate applied to the buccal ganglia mimicked both the excitatory and inhibitory effects of subunit 2 (S2) of the tripartite central pattern generator (CPG) on S2 postsynaptic motor neurons. Here we identify buccal interneuron B2 as an S2 interneuron by utilizing a combination of electrophysiology, pharmacology, and intracellular staining. In addition, neurons that were electrophysiologically and morphologically characterized as neuron B2 demonstrated antiglutamate immunoreactivity, suggesting that neuron B2 is a source of endogenous glutamate in the buccal ganglia. 2. Depolarization of neuron B2 evoked excitatory postsynaptic potentials in motor neurons excited by S2. The excitatory effects of B2 depolarization and S2 activation were reversibly antagonized by the ionotropic glutamate receptor antagonist 6-cyano-7-nitro-quinoxaline-2,3-dione, similar to the antagonism shown previously for application of exogenous glutamate. Depolarization of neuron B2 also evoked inhibitory postsynaptic potentials in motor neurons inhibited by S2. When such motor neurons were maintained in isolated cell culture, application of exogenous glutamate produced a direct hyperpolarization of the membrane potential. 3. The activity of neuron B2 is necessary for the production of the standard pattern of buccal motor neuron activity, which underlies functional feeding movements. The subunits of the tripartite buccal CPG must be active in the temporal sequence S1-S2-S3 to produce the standard feeding pattern. Rhythmic inhibition from neuron B2 terminated activity in S1 postsynaptic motor neurons and entrained the frequency of activity in S3 postsynaptic motor neurons. Hyperpolarization of neuron B2 disrupted the production of the standard motor pattern by eliminating S2 postsynaptic potentials in identified buccal motor neurons, thereby prolonging S1 activity and disrupting S3 bursting. 4. These data support the hypothesis that S2 neuron B2 is glutamatergic and demonstrate that glutamatergic transmission, and especially inhibition, is fundamental to the production of behaviorally critical motor neuron activity patterns in Helisoma.

An analysis of the contact phase of blood coagulation: effects of shear rate and surface are intertwined

This work analyzes, for the first time, the combined role of blood flow, protein transport and the reaction network of the contact phase up to the "common pathway" of the blood coagulation cascade. The model is comprised of a set of 20 dominant reactions with 11 components. Systems of ODEs reducible to 4 coupled equations describe rigorously the dynamic behavior, while systems of algebraic equations, reducible to a single polynomial equation, model the steady state concentrations of the coagulants. The analysis showed that there is never more than one stable steady state. This is in contrast to the analysis of common pathway that gives rise to multiple concentration states. It also revealed a general robustness of the system to changes in procoagulant concentrations, inhibition rates and most activation rate constants. The system is largely impervious to the level of activated Factor XII, given that a trace (non-zero) level is present. In contrast, the system displays a dual response to flow and surface activity: A change in either of these factors alone can promote, have no effect on, or (in the case of flow) impede the progress of coagulation, depending on the value of the other factor. Their effects must therefore be examined in unison. These results may help resolve contradictory findings attributed to one or the other factor alone.

Returning to primary school after treatment for cancer

Questionnaires were sent to the teachers of 14 children returning to school after treatment for childhood cancer and their 11 siblings. Forty-four control children from the same classes were also selected. Behavioral rating scores (Deasy-Spinetta) showed no differences between cases and siblings or control children in terms of learning disabilities, socialization, and emotional behavior. Teachers reported few problems on the case children's return to school, although many had been anticipated. Most children adapted well, and there were no major changes in behavior or performance. Siblings, too, coped well with the experience. The Royal Victoria Infirmary at Newcastle, where the children were treated, has two community liaison nurses and three social workers. The value of the support that they provide to both families and schools is clearly reflected in the ease with which children reintegrate into their school environment after what can be, for some, a prolonged absence.

Evaluation of routine diabetes and lipid screening after age 35 in candidates for or current users of oral contraceptives

OBJECTIVE

To evaluate the efficacy of a diabetes and lipid screening program in women aged 35 or older who either were currently using a low-estrogen-dose oral contraceptive (OC) (0.03-0.04 ethinyl estradiol) or who desired to initiate low-dose OC therapy after using a non-OC method or following a recent pregnancy.

METHODS

Healthy women with no history of abnormal glucose tolerance, hypertension, or hyperlipidemia aged 35 years and older were routinely screened for diabetes (fasting and 2-hour values after 75 g glucose) and dyslipidemia (fasting total cholesterol, high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol, and triglycerides). Three groups of women were studied: women currently using low-dose OCs (OC group), women desiring to change to OC therapy (non-OC group), and women within 3 months post-pregnancy (postpartum group).

RESULTS

The three groups were similar in age, parity, body mass index (BMI), and mean arterial pressure. The mean months of contraceptive use were not different between the OC group (30.2 months; 95% confidence interval [CI] 26.6-33.8) and the non-OC group (38.4 months; 95% CI 32.0-44.8). The mean fasting serum glucose, after adjusting for age and BMI, was significantly lower in the OC group (82.4 +/- 9.4 mg/dL) than in the non-OC and postpartum groups (87.2 +/- 12.5 and 86.8 +/- 13.0 mg/dL, respectively; P = .01). After adjustments, no differences between the groups were found in the 2-hour post-glucose levels, triglycerides, or HDL or LDL cholesterol levels. The non-OC group was found to have a significantly lower total cholesterol level (188.7 +/- 32.4 mg/dL) than the OC and postpartum groups (202.7 +/- 38.1 and 204.4 +/- 41.0 mg/dL; P = .02) after adjusting for age and BMI. This association lost its significance after applying multiple range tests, maintaining an alpha error of 0.05.

CONCLUSION

The absence of significant adverse metabolic markers in longer-term OC users over the age of 35, in comparison to similar-age control groups, does not support the routine use of lipid and diabetes screening before initiating or during the use of low-dose OCs.

Relaxation of vascular smooth muscle induced by low-power laser radiation

The relaxation of rabbit aorta rings induced by low-power laser radiation was investigated in vitro to determine the location of the chromophore(s) responsible for this response and evaluate possible mechanisms. An action spectrum for relaxation was measured on rabbit thoracic aorta rings precontracted with norepinephrine. The decrease in isometric tension was measured during exposure to laser light (351-625 nm) delivered via a fiber optic to a small spot on the adventitial surface. The shortest UV wavelength (351 nm) was 35-fold more effective than 390 nm and 1700-fold more effective than 460 nm. Ultraviolet wavelengths also produced greater maximum relaxation (0.40-0.45) than visible wavelengths (0.20-0.25), suggesting that photovasorelaxation involves more than one chromophore. The adventitial layer was not necessary for photovasorelaxation, indicating that the light is absorbed by a chromophore in the medial layer. The same degree of relaxation was obtained on rings without adventitia when either one-half of the ring, or a small spot was irradiated indicating that communication between smooth muscle cells spreads a signal from the area illuminated to the entire ring. The mechanism for photovasorelaxation was investigated using potential inhibitors. N-monomethyl-L-arginine and N-amino-L-arginine, inhibitors of nitric oxide synthase, did not alter photovasorelaxation nor did indomethacin, an inhibitor of cyclooxygenase, and zinc protoporphyrin, an inhibitor of heme oxygenase.

Removal of retained intrauterine contraceptive devices in pregnancy

Using real-time ultrasound and clinical expertise gained from chorionic villus sampling, we describe a technique for ultrasound-guided intrauterine device removal in those cases in which the string is not visible. Utilizing a stone clamp for intrauterine manipulation, we were easily able to extract the device without interrupting the pregnancy. We concur with recent recommendations advocating all intrauterine devices can be removed if pregnancy termination is declined.

Optical coherence tomography

A technique called optical coherence tomography (OCT) has been developed for noninvasive cross-sectional imaging in biological systems. OCT uses low-coherence interferometry to produce a two-dimensional image of optical scattering from internal tissue microstructures in a way that is analogous to ultrasonic pulse-echo imaging. OCT has longitudinal and lateral spatial resolutions of a few micrometers and can detect reflected signals as small as approximately 10(-10) of the incident optical power. Tomographic imaging is demonstrated in vitro in the peripapillary area of the retina and in the coronary artery, two clinically relevant examples that are representative of transparent and turbid media, respectively.

Self-generated mnemonics for enhancing free recall performance in older learners

The effectiveness of self-generated mnemonic strategies for free-recall list learning was examined in 94 older community-dwelling adults. Participants were presented with a list of 19 nouns and were given seven minutes to commit the list to memory with three minutes for recall. Performance was measured immediately following recall and after a 2-day delay. Forty-five percent of the participants reported using a specific organizational mnemonic encoding strategy to facilitate recall. At both immediate and delayed recall, those individuals who reported using a well-articulated mnemonic outperformed those reporting the use of repetition or making simple associations. The results suggest that many older adults can spontaneously generate specific elaborative encoding strategies and that pre-existing encoding skills should be assessed prior to remedial memory training for older adults.

Beyond drug effects and dependent variables: the use of the Poisson-Erlang model to assess the effects of D-amphetamine on information processing

Several studies have shown that d-amphetamine (DAMP) speeds mean reaction time (RT). However, the use of mean RT may obscure important aspects of the drug response. Therefore we applied the Poisson-Erlang (PE) stochastic model of choice reaction time proposed by Pieters (1985) to the RT distribution. This model proposes that the RT distribution is generated by two states: Processing (P) and Distraction (D). RT represents the sum of the time spent in each of these states. P is the time taken to complete a set of cognitive operations which are required to give a correct response. D represents the time taken by all other activities. RTs were collected using a task (SERS) in which stimulus and response complexity each had two levels, easy and hard. Subjects were tested pre- and postdrug. Drug conditions were: placebo, 10 mg d-amphetamine (DAMP), 4 mg of the dopamine agonist, pimozide, and a combination of DAMP and pimozide (COMBO). Parameters of the model were derived using methods described by Pieters. Four measures were analyzed: Processing Time (PT); Mean Time per distraction (XTD); Distraction Rate (DR); and Total Distraction Time per trial (TDT). Mean RT is also presented. Analyses of the effects of task conditions on the parameters of the model were made using the predrug sessions. Mean RT was increased by both stimulus and response complexities as was PT. TDT was increased by the task conditions. The PE measures did not change over days. DAMP speeded mean RT. However, this effect did not interact with the task factors. DAMP speeded processing and reduced distraction. Processing was speeded only in the hard response condition, distraction time was reduced only in the easy response condition. The results indicate that the PE model can be successfully applied to fast RT tasks. More importantly, the parameters of the model revealed important pharmacological effects that were not apparent in mean RT. DAMP speeds cognitive operations related to motor preparation and reduces the effects of distraction. Consistent with past studies there are no indications that DAMP interacted with stimulus processing. The distraction effect appears to be mediated by an increase in the rate of distraction and a decrease in the average time of these distractions.

Medical students' expectations for encounters with minority and nonminority patients

The authors examined the expectations of firstyear medical students (n = 139) at the University of California, Los Angeles, School of Medicine in regard to interacting with black, Latino, Asian, and white patients. Using slides and a questionnaire, the results indicated that students expected to be significantly less comfortable interviewing blacks than other patients and to view blacks and Latinos as less likely to comply with treatment than whites and Asians. Black and Hispanic students were significantly more likely than white and Asian students to expect black and Hispanic patients to comply with treatment.

Which first-year medical students expect to practice in an inner-city or ghetto setting

The authors examined the expected practice location of first-year medical students at UCLA School of Medicine using self-administered questionnaires. The response rate was 94 percent. About 24 percent of students are from underserved minority groups. Compared with nonminority students, minority students are significantly older, of lower socioeconomic status, and more likely to have been raised in an inner-city or ghetto environment (each P<.05). While the average nonminority student expected to practice in a noninner-city, urban, or suburban environment, the average minority student expected to practice in an inner-city or ghetto environment (P<.0001). Differences in expected practice location due to ethnicity remained after controlling for sociodemographic factors. Students with previous medical experience and those from poorer sociodemographic backgrounds are also more likely to expect to practice in ghetto environments, regardless of ethnic background (each P<.05).

Determining the 'consumer object'

For each of us the world is a complex of dichotomous constructs clustering to form objects. Of importance to the marketing psychologist is the structure of 'consumer objects', and his aim is to determine the nature of these. The meaning of stimuli may be categorised into the denotive or functional physical aspects of being, and the connotive or emotive affectional aspects. Both are of importance in meeting consumer need. Denotive meaning is more obvious than connotive, and more covert means are necessary to uncover the latter. Examples are given of the results of such analyses of connotive being and a technique which enables a numerate assessment of the consumer object is described with an illustrative example.