Qualitative interviews to understand methods and systems used to collect ethnicity information in health administrative data sources in England

Background: This article is one of a series aiming to inform analytical methods to improve comparability of estimates of ethnic health disparities based on different sources. This article explores the quality of ethnicity data and identifies potential sources of bias when ethnicity information is collected in three key NHS data sources. Future research can build on these findings to explore analytical methods to mitigate biases. Methods: Thematic analysis of semi-structured qualitative interviews to explore potential sources of error and bias in the process of collecting ethnicity information across three NHS data sources: General Practice Extraction Service (GPES) Data for Pandemic Planning and Research (GDPPR), Hospital Episode Statistics (HES) and Improving Access to Psychological Therapies (IAPT). The study included feedback from 22 experts working on different aspects of health admin data collection for England (including staff from NHS Digital, IT system suppliers and relevant healthcare service providers). Results: Potential sources of error and bias were identified across data collection, data processing and quality assurance processes. Similar issues were identified for all three sources. Our analysis revealed three main themes which can result in bias and inaccuracies in ethnicity data recorded: data infrastructure challenges, human challenges, and institutional challenges. Conclusions: Findings highlighted that analysts using health admin data should be aware of the main sources of potential error and bias in health admin data, and be mindful that the main sources of error identified are more likely to affect the ethnicity data for ethnic minority groups. Where possible, analysts should describe and seek to account for this bias in their research.

Peer-led exercise program for ageing adults to improve physical functions - a randomized trial

Background

A peer-led exercise program is one way to empower people sharing similar characteristics to encourage others to be active, but there is a lack of evidence that these programs have physical function and other benefits when delivered to ageing adults.

Methods

This randomized controlled trial lasting 12 weeks proposed an exercise peer-led program offered to 31 adults aged 50 and above, twice a week, by a trained leader of the same age from March to May 2019. The program was offered for free with limited space and equipment. Valid tests of physical function (e.g., 30-s chair stand, 6-min walk test) were used to assess the functional benefits. Psychosocial outcomes were assessed using self-reported questionnaires and metabolic outcomes via a fasted blood draw.

Results

A significant difference was found between pre-and post-values in most physical function tests in the intervention group (all p < 0.05). When adjusted for potential confounders, the intervention group was significantly associated with a more significant improvement on the chair stand test (ß = .26; p < 0.001; r² = 0.26), the arm curl (ß = .29; p < 0.001; r² = 0.49), as well as the 6-min walk test (ß = -.14; p < 0.001; r² = 0.62) compared with the control group. Using repetitive measures generalized linear model, the interaction between the changes and the group was significant for all three tests. Benefits were also observed for participants’ stress level and perceived health in the intervention group compared to the control. Finally, no significant difference was observed between groups for metabolic health.

Conclusions

The current work suggests that a 12-week peer-led exercise program can improve physical function for adults age 50 and above.

Trial registration

NCT03799952(ClinicalTrials.gov) 12/20/2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11556-021-00257-x.

Coherence of marine alien species biosecurity legislation: A study of England and Wales

The marine environment is particularly at risk from the intentional and unintentional introduction and spread of invasive alien species (IAS); preventing their introduction and spread from occurring is therefore, a key component in the on-going management of marine IAS. Ensuring legislation is coherent and consistent is essential to the success of managing the existing and future impacts of marine IAS. We explore the coherence (determined as consistency and interaction) of marine biosecurity legislation for IAS at different geopolitical scales. There was consistency between both the Bern Convention and Convention on Biological Diversity and European and national legislation that had been created in response. There was a lack of interaction evidenced by the Ballast Water Management Convention, which had not yet been transposed into regional (mainly European) or national legislation. Implementation measures such as legislation should be coherent as any failure in the chain could potentially weaken the overall effort to establish and maintain biosecurity and achieve behaviour change.

The effectiveness of e-Learning on biosecurity practice to slow the spread of invasive alien species

Online e-Learning is increasingly being used to provide environmental training. Prevention measures including biosecurity are essential to reducing the introduction and spread of invasive alien species (IAS) and are central to international and national IAS policy. This paper is the first to evaluate the effectiveness of e-Learning as a tool to increase awareness, risk perception and biosecurity behaviour in relation to IAS among individuals conducting work activities or research (fieldwork) in the field. We surveyed participants (a mixture of students and professionals) before, and 6 months after undertaking an e-Learning course on IAS and biosecurity practices. Awareness of IAS and self-reported biosecurity behaviour increased after e-Learning among students and professionals. Students had a lower awareness of IAS than professionals before training (20% of students vs 60% of professionals), but after training students showed a greater increase in awareness which led to similar levels of awareness post-training (81%). Prior to training, risk perception was also lower amongst students than professionals (33% of students and 59% of professionals were aware of the risk that their activities posed to the accidental spread of IAS). There was no change in risk perception amongst professionals after training, however training led to a doubling of risk perception in students. E-Learning also led to an increase in reported biosecurity behaviour and cleaning practices and there were higher levels of biosecurity cleaning amongst professionals. The higher awareness and better biosecurity amongst professionals is likely to reflect their familiarity with the issues of IAS and day-to-day activities in the field. Our results suggest that e-Learning is an effective tool to raise awareness and encourage behaviour change among field workers and researchers in an attempt to reduce the risk of accidental introduction and spread of IAS.

Data Sharing, Clinical Trials, and Biomarkers in Precision Oncology: Challenges, Opportunities, and Programs at the Department of Veterans Affairs

Cancer genomic research reveals that a similar cancer clinical phenotype (e.g., non-small cell lung cancer) can arise from various mutations in tumor DNA. Thus, organ of origin is not a definitive classification. Further, targeted therapy for cancer patients (precision oncology) capitalizes on knowledge of individual patient mutational status to deliver treatment directed against the protein products of these mutations with the goal of reducing toxicity and enhancing efficacy relative to traditional nontargeted chemotherapy.

A phase II study of dose-dense chemotherapy (doxorubicin (A), cyclophosphamide (C), paclitaxel (T), gemcitabine (G)) supported by pegfilgrastim (P) and darbepoetin-alfa (D) for patients with high-risk early stage breast cancer (ICANDO)

11068

Background: The primary objective of this study was to estimate the proportion of chemotherapy dose delays in a dose- dense regimen consisting of A (60mg/m2), C (600 mg/m2) x 4 cycles q2 weeks followed by T (175 mg/m2) G (1g/m2) x 4 cycles q2w with pegfilgrastim (6 mg/m2 sc d2) and darbepoetin-alfa (2.25 microg/kg if Hb < 110g/L) as treatment for patients with high-risk early stage breast cancer. Dose delay was defined by the proportion of subjects experiencing delay = 7 days in any cycle. Entry criteria path stage IIA-IIIA breast adenocarcinoma; node positive patients > 6 axillary lymph nodes removed or sentinel LN biopsy positive for metastasis. Treatment commenced within 8 weeks. Secondary endpoints included proportion of delays by cycle, causes of delay by cycle, causes of dose reduction by cycle, as well as time to haematological engraftment. Patients underwent weekly FBC, electrolytes, LFTs, with a normal baseline echo assessment. Herceptin therapy was approved in Australia 1st October 2006 and was added to TG therapy for FISH/CISH/IHC 3+ positive patients. All patients completed FACT-F QOL forms. The half-width confidence interval to predict for delay based on the AC-T data is 0.17 for n = 20 patients. Results: Twenty (20) women; median age 50 (41–66) met the criteria for treatment. No patients had treatment delays ≥ 2 days for any reason. One (5%) patient underwent a blood transfusion for a rapid decline in haemoglobin (Hb) prior to darbepoetin therapy. One (5%) patient was admitted for uncontrolled vomiting. Seven (35%) patients received darbepoetin therapy without secondary Hb rise above 130 g/L. One (5%) patient had a 20% dose reduction in A dose due to mucositis. For nausea >G1 aprepitant therapy was added. There have been no dose modifications due to hepatic toxicity. Final cycle, QOL and pharmacogenomic data will be presented at the meeting. [Table: see text]

No significant financial relationships to disclose.

Regimens of misoprostol with mifepristone for early medical abortion: a randomised trial

OBJECTIVE

To compare the efficacy, adverse effects and acceptability of the three most common misoprostol regimens used with mifepristone for medical abortion.

DESIGN

Randomised nonblinded trial.

SETTING

Three clinics associated with major research universities in Canada; two in major urban areas and one in a periurban area.

POPULATION

Women of reproductive age.

METHODS

Consenting women presenting for abortion services with gestations less than 56 days and who met inclusion criteria were given 200 mg mifepristone orally and then randomised into three misoprostol study groups: (group I) 400 micrograms of oral misoprostol, (group II) 600 micrograms of oral misoprostol, and (group III) 800 micrograms of vaginal misoprostol. Misoprostol was self-administered at home 24-48 hours following mifepristone, and participants were instructed to take a second similar misoprostol dose at 24 hours after the initial dose if bleeding was less than a normal menstrual period.

MAIN OUTCOME MEASURES

Successful abortion without surgery was 94.1%, with no significant differences across the three study groups (94.7% in group I, 93.4% in group II, and 94.3% in group III; P= 0.975).

RESULTS

Efficacy and adverse effects did not differ significantly across the three study groups. Pain increased significantly across the study and the gestational age groups and was associated with lower acceptability.

CONCLUSIONS

There appears to be a range of safe and effective options for early medical abortion with mifepristone including a choice between oral and vaginal administration of misoprostol.

Outcomes and health status of patients undergoing usual care for highly emetogenic chemotherapy

18591

Background: Chemotherapy-induced nausea and vomiting (CINV) remains a significant issue for patients, especially management of delayed symptoms. The Perugia 2004 antiemetic guidelines recommended that anthracycline/cyclophosphamide (A/C) combination regimens be considered as high risk emetogenic potential. The aim of our study was to determine the extent of CINV, and effect on quality of life for chemotherapy-naïve patients in a practice-based environment. Methods: Eligible patients were receiving their 1st cycle of high risk emetogenic or carboplatin chemotherapy, administered with “standard care” (5HT3 antagonist + dexamethasone) antiemetics (use of NK1 antagonists excluded). Patients completed a daily diary for 5 days post chemotherapy, capturing data on CINV activity and rescue medications usage. Emesis and nausea-specific health status was measured by the Functional Living Index - Emesis (FLIE); general health status was assessed using a 100mm VAS (EQVAS). Results: Of 74 patients, 42 received an A/C regimen, 16 cisplatin and 16 carboplatin. Overall complete response (no vomiting, no use of rescue antiemetics during the study period) was 60% in patients receiving carboplatin, 24% A/C and 21% cisplatin. During the delayed phase, mean total emesis episodes for carboplatin was 0.6, A/C 2.21 and cisplatin 4.08. Patients receiving carboplatin reported less delayed nausea, and better outcomes for FLIE and EQVAS scores. Treatment with either A/C or cisplatin was associated with similar deterioration in nausea control across the study period, and similar impact on FLIE scores (see table ). Conclusions: Our results are consistent with the recommendation that A/C regimens be considered highly emetogenic, with similar impact on patient symptoms and quality of life compared with cisplatin. Delayed CINV remains a target for antiemetic intervention. Similar studies need to be repeated in patients receiving additional NK1 antagonists to assess their impact on CINV outside clinical trials.

[Table: see text]

[Table: see text]

Knowledge and attitudes about abortion legislation and abortion methods among abortion clients in Latvia

OBJECTIVE

To assess knowledge of abortion legislation and knowledge and attitudes about medical and surgical abortion among women seeking a legal abortion in Latvia.

METHODS

Data are drawn from a survey of 371 abortion clients from 16 purposively selected abortion clinics in Latvia. A semi-structured questionnaire was used to collect socio-demographic data and information on women's knowledge of and attitudes toward abortion law and abortion methods.

RESULTS

Most women knew that abortion is legal either under any (53%) or certain (37%) circumstances. Almost one third (31%) of women interviewed were aware of medical abortion. After hearing a description of medical abortion, respondents felt the method as described would be advantageous because it could avoid a surgical intervention (33%) or found it simple, easy, convenient, or natural (12%). Women were concerned that the method might not be completely effective (38%) or be associated with side-effects (22%).

CONCLUSIONS

Respondents were interested in medical abortion as a less invasive option to surgical abortion. Efforts should be undertaken to inform women about the safety and efficacy of the method.

Early Experience and Sex Interact to Influence Limbic-Hypothalamic-Pituitary-Adrenal-Axis Function After Acute Alcohol Administration in Rhesus Macaques (Macaca mulatta)

BACKGROUND

Studies in rodents demonstrate sex differences in neuroendocrine stress axis activity after treatment with alcohol. In abstinent alcoholics, atypical depressives, and individuals with posttraumatic stress disorder, limbic-hypothalamic-pituitary-adrenal (LHPA)-axis activity is often blunted; among females in these patient populations, however, resistance to glucocorticoid feedback and increased pituitary reactivity is observed. Early parental loss is a major life stressor and is a risk factor for both affective disturbances and LHPA-axis abnormalities later in life. We wanted to determine whether sex and early life parental absence would interact to influence alcohol-induced alterations in LHPA-axis activity after exposure to ethanol in macaques.

METHODS

Animals were reared with their mothers in social groups (MR, n = 94) or without adults in peer-only groups (PR, n = 79). At 5 years of age, they received an intravenous infusion of alcohol (2-2.2 g/kg), and the effects of alcohol, sex, and rearing condition on ACTH and cortisol levels were analyzed by ANOVA.

RESULTS

Peer-reared females had higher ACTH levels than did PR males, MR females, and MR males after alcohol infusion. Alcohol-induced cortisol levels were not affected by sex and rearing condition.

CONCLUSIONS

These findings suggest that there are sex differences in glucocorticoid negative feedback, pituitary responsivity, or release of ACTH secretagogues among individuals exposed to early life stress and emphasize the importance of considering sex effects when studying LHPA-axis dysregulation in alcoholism and other stress-related neuropsychiatric disorders.

Breast cancer in adolescents and young women

Breast cancer is very rare in adolescents and very young women. Less than 1% of all breast cancer cases occur before the age of 30 years (Natl Cancer Inst Monogr 16 (1994) 69). Invasive breast cancer occurring in women before the age of 35 years has a more aggressive biological behaviour and is associated with a worse prognosis than in older premenopausal women. Breast cancers in these young women are more frequently poorly differentiated, oestrogen-receptor (ER)-negative, have lymphovascular invasion and high proliferating fractions. Breast-conserving surgery in women <35 years old is associated with a higher risk of local recurrence than in older women. All young women should be considered at moderate-high risk by virtue of their age alone and offered adjuvant therapy. The long-term toxicity of adjuvant therapies is a particular concern when treating these women. The implications of possible fertility impairment and premature menopause require consideration when discussing adjuvant chemotherapy and endocrine therapy. Adolescents and young women are particularly vulnerable to emotional distress and psychosocial problems and should be provided with appropriate support. Young women who are at a potential high-risk of developing breast cancer such as those with germline mutations of BRCA1, BRCA2, TP53, PTEN or who have previously received mantle irradiation for Hodgkin's disease need close follow-up and are candidates for screening from a young age.

Does Timing of Adjuvant Chemotherapy for Early Breast Cancer Influence Survival?

Purpose: Theoretically, patients with early breast cancer might benefit from starting adjuvant chemotherapy soon after surgery, and this would have important clinical implications. We have addressed this question from a large, single-center database in which the majority of patients received anthracyclines.

Patients and Methods: A total of 1,161 patients from a prospectively maintained database treated with adjuvant chemotherapy for early breast cancer at the Royal Marsden Hospital (London, United Kingdom), including 686 (59%) receiving anthracyclines, were retrospectively analyzed. The disease-free survival (DFS) and overall survival (OS) of the 368 patients starting chemotherapy within 21 days of surgery (group A) were compared with those of the 793 patients commencing chemotherapy ≥ 21 days after surgery (group B). Median follow-up time was 39 months (range, 12 to 147 months).

Results: No significant difference in 5-year DFS was found between the two groups overall (70% for group A v 72% for group B; P = .4) or in any subgroup. Likewise, there was no difference in 5-year OS (82% for group A v 84% for group B; P = .2) or when the interval to the start of chemotherapy was considered as a continuous variable (P = .4).

Conclusion: We have been unable to identify any significant survival benefit from starting adjuvant chemotherapy early after surgery, either overall or in any subset of patients.

Serotonin transporter gene polymorphism, differential early rearing, and behavior in rhesus monkey neonates

A polymorphism in the serotonin (5-HT) transporter gene regulatory region (5-HTTLPR) is associated with measures of 5-HT transporter (5-HTT) expression and 5-HT-mediated behaviors in humans. An analogous length variation of the 5-HTTLPR has been reported in rhesus monkeys (rh5-HTTLPR). A retrospective association study was conducted on 115 rhesus macaque infants either homozygous for the long 5HTTLPR variant (l/l) or heterozygous for the short and long form (l/s). To assess contributions of genotype and early rearing environment, 36 mother-reared monkeys (l/l = 26, l/s = 10) and 79 nursery-reared monkeys (l/l = 54, l/s = 25) were assessed on days 7, 14, 21, and 30 of life on a standardized primate neurobehavioral test designed to measure orienting, motor maturity, reflex functioning, and temperament. Both mother-reared and nursery-reared heterozygote animals demonstrated increased affective responding relative to l/l homozygotes. Nursery-reared, but not mother-reared, l/s infants exhibited lower orientation scores than their l/l counterparts. These results demonstrate the contributions of rearing environment and genetic background, and their interaction, in a nonhuman primate model of behavioral development.

Carboplatin and gemcitabine in metastatic transitional cell carcinoma of the urothelium: effective treatment of patients with poor prognostic features

PURPOSE

To evaluate the activity and toxicity of gemcitabine and carboplatin in consecutive patients presenting with locally advanced or metastatic transitional cell carcinoma of the urothelium (TCC).

PATIENTS AND METHODS

Seventeen consecutive patients referred to a single institution with locally advanced or metastatic TCC were treated with carboplatin AUC 5 on day 1 and gemcitabine 1000 mg/m2 on day 1 and 8 of a 21-day cycle. All patients were assessable for response and toxicity. Minimal eligibility criteria were used to minimize patient selection.

RESULTS

Seventeen patients with measurable stage IV TCC of the urothelium were treated. The median age was 69 years (range 54-78), the median creatinine clearance was 56 ml/min (range 34-90) and 30% of patients had an ECOG performance score of two. Nine patients (53%) had visceral metastases and the majority of patients had multiple sites of metastases. There were three complete responses, seven partial responses, for an overall response rate of 58.8%. Responses were seen at all sites including the liver. One patient had a response within a previously irradiated field and three patients with prior chemotherapy had responses. Median overall survival was 10.5 months and median time to progression was 4.6 months. Toxicity was primarily haematologic with six patients having grade 3 neutropenia and six patients with grade 4 neutropenia. There were five cases of grade 3 and three cases of grade 4 thrombocytopenia. There were no episodes of febrile neutropenia and only one patient required admission for management of toxicity. Thirteen patients required dose reduction or delay due to neutropenia or thrombocytopenia. There were no treatment-related deaths.

CONCLUSION

The combination of carboplatin and gemcitabine is active in metastatic transitional cell carcinoma of the urothelium with manageable toxicity in a relatively elderly group of patients with some poor prognostic features.

High prevalence of asthma in five remote indigenous communities in Australia

Data on the prevalence of asthma in children residing in remote indigenous communities in Australia are sparse, despite the many reports of high prevalence in nonindigenous children of this country. Two previous Australian studies have had poor participation rates, limiting interpretation of their results. A study of children in the Torres Strait and Northern Peninsula Area of Australia was conducted to document the prevalence of asthma symptoms. Five indigenous communities were randomly selected and trained interviewers, who were local indigenous health workers, recruited participants using a house-by-house approach. Information was collected by a structured face-to-face interview based on a standardized questionnaire constructed from the protocol International Study of Asthma and Allergy in Childhood; 1,650 children were included in the study with a 98% response rate. Overall, the prevalence of self-reported ever wheezing was 21%; 12% reported wheezing in the previous year; and 16% reported ever having asthma. There was significant variation in the prevalence of asthma symptoms between communities. It is concluded that there are significant intercommunity variations in the prevalence of asthma symptoms in remote communities and that the prevalence in these communities is as high as in nonindigenous groups.

To be or not to be: recording Aboriginal identity on hospital records

Accurate health information is a key component in the development of health improvement strategies. This paper provides a discussion of the challenges in improving hospital information systems in relation to indigenous patients. Based on interviews with both staff and patients of a major city hospital complex, a picture emerges of the need for bottom-up approaches to understanding perceptions of identity. Indigenous patients were found to be generally comfortable about identifying themselves on hospital records (if asked), but were often not clear why such questions were asked. On the other hand hospital staff were often uncomfortable about asking and were equally not always clear why such information was needed. Issues of accurate hospital record administration are discussed in relation to the attitudes and perceptions of both staff and patients.

Assessment of a two-generation reproductive and fertility study of mercuric chloride in rats

Effects of mercuric chloride (MC) on the reproductive performance of two successive generations of rats was evaluated. F(0) rats were exposed to 0.0:0.0 (males:females), 0.50:0.75 (males:females), 1.00:1.50 (males:females) and 1.50:2.50 (males:females) mg/kg/day MC. Selected parental F(1) males and females were exposed to the same doses received by their parents (F(0)). Significant differences resulting from exposure of the F(0) generation to MC were found in implantation efficiency, fertility, live births and day 4 survival indices, litter size, and the body weight of F(1) pups. However, the continued exposure of the F(1) generation to MC did not affect fertility index or litter size, but did significantly affect implantation efficiency, live births and day 4 survival indices. In F(0) males, body weight and weights of the kidneys, testes, epididymides, prostate and seminal vesicles were significantly different, while in F(1) males, body weight, kidney weight, brain weight, liver weight and the weights of the testes, prostate and seminal vesicles were significantly different. In F(0) females, body weight and the weights of the kidneys, brain and liver were significantly different, while in F(1,) females, body weight, as well as the weights of the kidneys, liver, adrenals, uterus and ovaries were significantly different. These data showed that exposure to MC resulted in more adverse reproductive effects in the first generation and that these effects moderated in the second generation.

Rearing condition and plasma cortisol in rhesus monkey infants

Previous studies comparing plasma cortisol levels in mother-reared and nursery-reared rhesus monkey infants under baseline and stress conditions have reported conflicting findings. Differences in subject age, procedures, and specific rearing history may account for many of the discrepant findings. In the present study, mother-reared infants from large social groups, peer-only reared animals, and infants reared with surrogates and limited peer contact were studied in different test conditions across the first 6 months of life. Infants were sampled under three conditions: following a neonatal assessment at Days 14 and 30, immediately upon capture on Day 60, and after 30-min isolation periods on Days 90, 120, and 150. Mother-reared infants exhibited higher cortisol levels on Days 14 and 30 than did both types of nursery-reared infants. In addition, Day 60 basal values of mother-reared infants were higher than those of both peer-reared and surrogate/peer-reared infants. However, on Days 90, 120, and 150, both mother-reared and peer-reared infants exhibited higher cortisol levels in response to separation and 30-min isolation than did the surrogate/peer-reared infants. These differences may reflect group-specific variations in physical environment, capture time, feeding regimen, or diurnal HPA axis rhythms.

Asthma management in indigenous children of a remote community using an indigenous health model

OBJECTIVE

To describe the management of asthma in children in a remote indigenous community and the delivery of subspecialist service through the indigenous health-care model.

METHODOLOGY

Children referred by indigenous health-care workers were evaluated prospectively by paediatric respiratory physicians, based on a standardized protocol, at a primary health care setting at Thursday Island, Queensland.

RESULTS

Forty of the 54 children referred with a provisional diagnosis of asthma did have asthma, with 30% having persistent asthma. Only 59% of parents knew the dose of the medication prescribed and 80% had minimal knowledge of the medications. In 88% of children, the management of asthma was improved by introduction of an appropriate spacer device and changing the dose and type of medications.

CONCLUSIONS

The management of children with asthma in the Torres region can be improved substantially by the use of age appropriate delivery devices and medications, and improving knowledge of asthma. Specialist delivery service to remote indigenous communities can be effectively delivered in partnership with the indigenous health service. The high proportion of persistent asthma in the Torres Straits community in comparison to urbanised Australia raises issues of inequity of appropriate medical service delivery to remote indigenous communities.

Heterogeneous immunosensing using antigen and antibody monolayers on gold surfaces with electrochemical and scanning probe detection

We report the use of antibody and antigen monolayer immunosurfaces as detection elements in a competitive heterogeneous immunoassay employing either electrochemical or scanning probe detection. Antibody or antigen monolayers were prepared by covalent attachment of the desired immunoreagent to a two-component self-assembled monolayer via amide linkages. More specifically, mixed monolayers of a carboxylic acid-terminated thiol (thioctic acid) and a methyl-terminated thiol (butanethiol) were used to control the surface epitope density. The microscopic structure of the resulting antibody and antigen arrays was characterized by AFM (atomic force microscopy). Individual, surface-confined rabbit IgG antibodies could be directly imaged in contact mode. The average height of the capture antibodies was found to be 7.1 nm; the average antibody diameter, after correcting for tip convolution effects, was determined to be between 7 and 10 nm. The surface epitope density could be varied over approximately 2 orders of magnitude by changing the composition of the mixed monolayer. AFM was also used to characterize the antibody-antigen binding characteristics of these immunosurfaces, and an average binding efficiency of 22.8% was measured for rabbit IgG antibody arrays. In the second part of this study, the electrochemical detection scheme originally developed by Heineman and co-workers was adapted to our system. A calibration data set was measured, and the linear least-squares correlation coefficient (R2) was found to be 0.993. Finally, the electrochemical and scanning probe detection modes were directly compared. We find an excellent correlation between the surface density of antibody-antigen complexes measured by AFM and the electrochemical response of the same immunosurfaces.

Burkitt's lymphoma associated with Helicobacter pylori

The association between Helicobacter pylori infection and low grade mucosa-associated lymphoid tissue lymphoma is now widely accepted. In this report, we describe the concurrent development of Burkitt's lymphoma in the stomach of a 53-year-old male with perforated duodenal ulcer and positive H. pylori serology. The temporal relationship between these two events raises the possibility of a causal link between H. pylori infection and this lymphoproliferative disease. In describing this rare case of gastric Burkitt's lymphoma, we consider the evidence that supports this possibility.

Community perceptions of health, illness and care: identifying issues for indigenous communities

Community meetings, interviews with key informants, and focus groups were used to document major health concerns and problems among Indigenous women in Queensland, as part of the Australian Longitudinal Study on Women's Health. In this article, we analyze understandings of "community" as used in Australian health research and among Indigenous women. We then examine health issues as identified and experienced by women and explore the gaps that exist between community concerns, individual health status, and service delivery.

Placental transfer of fentanyl in early human pregnancy

To investigate the transfer of fentanyl across the early human placenta, we have collected samples of maternal blood and fetal fluids and/or blood, simultaneously, between 5 and 22 min following an intravenous bolus of fentanyl (1.5 microg/kg) to the mother. The pregnancies were between 6 and 16 weeks of gestation and scheduled for elective termination of pregnancy under general anaesthesia. Total fentanyl concentration was determined by radioimmunoassay in 11 pairs of first trimester maternal serum and fetal coelomic fluid samples, 14 pairs of maternal serum and amniotic fluid samples, seven series of first trimester maternal serum and coelomic and amniotic fluid samples, and 10 series of early second trimester maternal and fetal sera and amniotic fluid samples. Fentanyl was not detected in coelomic fluid samples at any gestational age and in amniotic fluid samples collected after 12 weeks of gestation. Measurable concentrations of fentanyl were found in maternal serum collected within 15 min after the initial bolus and in fetal serum collected between 10 and 12 min later. These findings indicate that fentanyl is transferred across the early placenta into the amniotic cavity and fetal blood circulation but not into the exocoelomic cavity. The distribution of this molecule inside the early gestational sac is probably influenced by the increased binding by maternal and fetal sera, its short half-life of distribution and the specific biology of the fetal fluid formation and composition.

Electrical potential difference between exocelomic fluid and maternal blood in early pregnancy

The forces that drive transfer of solutes between maternal blood and embryo in early human pregnancy are poorly understood. The aim of this study was to determine whether there is an electrical potential difference (PD) between maternal blood and the exocelomic cavity and between maternal blood and the amniotic cavity in the normal human conceptus at or before 10 wk of pregnancy. We measured PD between a saline-filled catheter in a forearm vein of women undergoing termination of pregnancy for psychological reasons in the first trimester and a second saline-filled catheter in the exocelomic cavity or amniotic cavity of their conceptus. The mean (+/- SE) maternal blood/exocelomic cavity PD in eight women was 8.7 +/- 1.0 mV and the mean maternal blood/amniotic cavity PD in four of the women was 6.7 +/- 1.3 mV, embryo side negative for both sets of measurement. These data show that there is a PD between maternal and embryonic extracellular fluid in the first trimester that will directly influence exchange of ions between the two compartments.

Types I and III collagen in the tissue capsules of titanium and stainless-steel implants

Collagen plays an important role in wound healing and as such is present in connective tissue capsules around implanted materials. The proportion of type I collagen to type III collagen is lower during wound healing than that found in normal dermis, but the amount of type I collagen gradually increases and type III decreases as healing continues. The intent of this research was to investigate a possible correlation between implant metals and type I and type III collagen formation in the ensuing soft-tissue capsules. Smooth implants of grade 4 commercially pure titanium and 316L stainless steel were placed via injection needle into the subcutaneous tissue of 12 rats for 6 weeks. The soft-tissue capsule that formed around each implant was evaluated histologically and by immunofluorescence. Although the two metal implant types differ in many respects, they were chosen for their differences in surface conductivity. Titanium oxide is semiconducting, whereas the oxide of stainless steel is conducting. Impedance spectroscopy was used for conductivity analysis of the surface. No qualitative differences were found in amount of type I or type III collagen in the capsules of the two metals. However, the capsules around titanium stained for type I collagen were thicker than capsules around stainless steel. In addition, type I collagen showed evidence of a greater association with densely packed, highly orientated collagen fibers.