Advice only versus advice and a physiotherapy programme for acute traumatic anterior shoulder dislocation: the ARTISAN RCT

Background

The extra benefit of a programme of physiotherapy in addition to advice alone, following first-time traumatic shoulder dislocation, is uncertain. We compared the clinical and cost-effectiveness of a single session of advice with a single session of advice and a programme of physiotherapy.

Objective

The primary objective was to quantify and draw inferences about observed differences in the Oxford Shoulder Instability Score between the trial treatment groups 6 months post randomisation, in adults with a first-time traumatic shoulder dislocation.

Design

A pragmatic, multicentre, superiority, randomised controlled trial with embedded qualitative study.

Setting

Forty-one hospitals in the UK NHS.

Participants

Adults with a radiologically confirmed first-time traumatic anterior shoulder dislocation, being managed non-operatively. People with neurovascular complications or bilateral dislocations, and those unable to adhere to trial procedures or unable to attend physiotherapy within 6 weeks of injury, or who had previously been randomised, were excluded.

Interventions

All participants received the same initial shoulder examination followed by advice to aid self-management, lasting up to 1 hour and administered by a physiotherapist (control). Participants randomised to receive an additional programme of physiotherapy were offered sessions lasting for up to 30 minutes, over a maximum duration of 4 months from the date of randomisation (intervention).

Main outcome measures

The primary outcome measure was the Oxford Shoulder Instability Score. This is a self-completed outcome measure containing 12 questions (0-4 points each), with possible scores from 0 (worst function) to 48 (best function). Measurements were collected at 6 weeks, 3 months, 6 months and 12 months by postal questionnaire; 6 months was the primary outcome time point. The primary health outcome for economic evaluation was the quality-adjusted life-year, in accordance with National Institute of Health and Care Excellence guidelines.

Results

Between 14 November 2018 and 14 March 2022, 482 participants were randomised to advice (n = 240) or advice and a programme of physiotherapy (n = 242). Participants were 34% female, with a mean age of 45 years, and treatment arms were balanced at baseline. There was not a statistically significant difference in the primary outcome between advice only and advice plus a programme of physiotherapy at 6 months for the primary intention-to-treat adjusted analysis (favours physiotherapy: 1.5, 95% confidence interval -0.3 to 3.5) or at earlier 3-month and 6-week time points on the Oxford Shoulder Instability Score (0-48; higher scores indicate better function). The probability of physiotherapy being cost-effective at a willingness-to-pay threshold of £30,000 was 0.95.

Conclusions

We found little difference in the primary outcome or other secondary outcomes. Advice with additional physiotherapy sessions was found likely to be cost-effective. However, small imprecise incremental costs and quality-adjusted life-years raise questions on whether it is the best use of scarce physiotherapy resources given current service demands.

Limitations

Loss to follow-up was 27%; however, the observed standard deviation was much smaller than anticipated. These changes in parameters reduced the number of participants required to observe the planned target difference of four points. Our post hoc sensitivity analysis, accounting for missing data, gives similar results.

Future work

Further research should be directed towards optimising self-management strategies.

Study registration

This study is registered as ISRCTN63184243.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 16/167/56) and is published in full in Health Technology Assessment; Vol. 28, No. 22. See the NIHR Funding and Awards website for further award information.

Dual ancestries and ecologies of the Late Glacial Palaeolithic in Britain

Genetic investigations of Upper Palaeolithic Europe have revealed a complex and transformative history of human population movements and ancestries, with evidence of several instances of genetic change across the European continent in the period following the Last Glacial Maximum (LGM). Concurrent with these genetic shifts, the post-LGM period is characterized by a series of significant climatic changes, population expansions and cultural diversification. Britain lies at the extreme northwest corner of post-LGM expansion and its earliest Late Glacial human occupation remains unclear. Here we present genetic data from Palaeolithic human individuals in the United Kingdom and the oldest human DNA thus far obtained from Britain or Ireland. We determine that a Late Upper Palaeolithic individual from Gough's Cave probably traced all its ancestry to Magdalenian-associated individuals closely related to those from sites such as El Mirón Cave, Spain, and Troisième Caverne in Goyet, Belgium. However, an individual from Kendrick's Cave shows no evidence of having ancestry related to the Gough’s Cave individual. Instead, the Kendrick’s Cave individual traces its ancestry to groups who expanded across Europe during the Late Glacial and are represented at sites such as Villabruna, Italy. Furthermore, the individuals differ not only in their genetic ancestry profiles but also in their mortuary practices and their diets and ecologies, as evidenced through stable isotope analyses. This finding mirrors patterns of dual genetic ancestry and admixture previously detected in Iberia but may suggest a more drastic genetic turnover in northwestern Europe than in the southwest.

The authors report genetic, archaeological and stable isotopic data from two late Palaeolithic individuals in Britain, from Gough's Cave and Kendrick's Cave. The individuals differ not only in their ancestry but also their diets, ecologies and mortuary practices, revealing diverse origins and lifeways among inhabitants of late Pleistocene Britain.

What is known from the existing literature about self-management of pessaries for pelvic organ prolapse? A scoping review

OBJECTIVES

Pelvic organ prolapse can be managed with a pessary. However, regular follow-up may deter women due to the inconvenience of frequent appointments, as well as preventing autonomous decision making. Pessary self-management may be a solution to these issues. However, there remains a number of uncertainties regarding pessary self-management. This scoping review aims to map available evidence about pessary self-management to identify knowledge gaps providing the basis for future research.

DESIGN

Scoping review as detailed in the review protocol.

DATA SOURCES

A search of MEDLINE, CINAHL, EMBASE and PsycINFO databases and a handsearch were undertaken during May 2021 to identify relevant articles using the search terms 'pessary' and 'self-management' or 'self-care'.

DATA EXTRACTION AND SYNTHESIS

Data relevant to pessary self-management was extracted and the Mixed Methods Appraisal Tool used to assess empirical rigour. Thematic analysis was performed to evaluate the results.

RESULTS

The database search identified 82 publications. After duplicates and articles not meeting the inclusion and exclusion criteria were removed, there were 23 eligible articles. A hand search revealed a further 19 articles, resulting in a total of 42 publications.Findings relevant to pessary self-management were extracted and analysed for the emergence of themes. Recurrent themes in the literature were; the characteristics of self-managing women; pessary care; factors associated with decision making about self-management; teaching self-management and cost benefit.

CONCLUSIONS

Pessary self-management may offer benefits to some women without increased risk. Some women do not feel willing or able to self-manage their pessary. However, increased support may help women overcome this. Further in-depth exploration of factors which affect women's willingness to self-manage their pessary is indicated to ensure better understanding and support as available for other conditions.

Subacromial balloon spacer for irreparable rotator cuff tears of the shoulder (START:REACTS): a group-sequential, double-blind, multicentre randomised controlled trial

BACKGROUND

New surgical procedures can expose patients to harm and should be carefully evaluated before widespread use. The InSpace balloon (Stryker, USA) is an innovative surgical device used to treat people with rotator cuff tears that cannot be repaired. We aimed to determine the effectiveness of the InSpace balloon for people with irreparable rotator cuff tears.

METHODS

We conducted a double-blind, group-sequential, adaptive randomised controlled trial in 24 hospitals in the UK, comparing arthroscopic debridement of the subacromial space with biceps tenotomy (debridement only group) with the same procedure but including insertion of the InSpace balloon (debridement with device group). Participants had an irreparable rotator cuff tear, which had not resolved with conservative treatment, and they had symptoms warranting surgery. Eligibility was confirmed intraoperatively before randomly assigning (1:1) participants to a treatment group using a remote computer system. Participants and assessors were masked to group assignment. Masking was achieved by using identical incisions for both procedures, blinding the operation note, and a consistent rehabilitation programme was offered regardless of group allocation. The primary outcome was the Oxford Shoulder Score at 12 months. Pre-trial simulations using data from early and late timepoints informed stopping boundaries for two interim analyses. The primary analysis was on a modified intention-to-treat basis, adjusted for the planned interim analysis. The trial was registered with ISRCTN, ISRCTN17825590.

FINDINGS

Between June 1, 2018, and July 30, 2020, we assessed 385 people for eligibility, of which 317 were eligible. 249 (79%) people consented for inclusion in the study. 117 participants were randomly allocated to a treatment group, 61 participants to the debridement only group and 56 to the debridement with device group. A predefined stopping boundary was met at the first interim analysis and recruitment stopped with 117 participants randomised. 43% of participants were female, 57% were male. We obtained primary outcome data for 114 (97%) participants. The mean Oxford Shoulder Score at 12 months was 34·3 (SD 11·1) in the debridement only group and 30·3 (10·9) in the debridement with device group (mean difference adjusted for adaptive design -4·2 [95% CI -8·2 to -0·26];p=0·037) favouring control. There was no difference in adverse events between the two groups.

INTERPRETATION

In an efficient, adaptive trial design, our results favoured the debridement only group. We do not recommend the InSpace balloon for the treatment of irreparable rotator cuff tears.

FUNDING

Efficacy and Mechanism Evaluation Programme, a Medical Research Council and National Institute for Health and Care Research partnership.

Developing chief investigators within the NHS: the West Midlands clinical trials scholars programme

Consecutive Royal College of Physicians' Research for all surveys have highlighted the challenges for doctors becoming involved in research. Local issues included under-representation of chief investigators (CIs) and reduction in dedicated research time. The West Midlands National Institute for Health Research (NIHR) Clinical Research Network (CRN) established a clinical trials scholarship (CTS) initiative in 2019 to develop research-active consultants in smaller trusts, with a dedicated day per week embedded in a local clinical trials unit. In the initial round of 41 applications from 13 partner organisations, 17 CTSs were appointed, including nine consultant physicians, with one subsequently deferring. After 2 years, the remaining 16 CTSs have been awarded 40 grants totalling £18.35 million as CI or co-CI, including 10 NIHR grants, plus >200 publications. These scholarships are a proven cost-effective way to develop CIs, provide academic leadership and promote a research culture, even in small, previously less research-active trusts.

What is known from the existing literature about self-management of pessaries for pelvic organ prolapse? A scoping review protocol

INTRODUCTION

Pelvic organ prolapse (POP) can be managed with a pessary; however, regular follow-up may deter women from pessary management due to the inconvenience of frequent appointments, as well as preventing pessary users from autonomous decision-making. Pessary self-management, whereby the woman removes and inserts her own pessary may be a solution to these issues. However, there remains a number of uncertainties regarding the potential benefits and risks of pessary self-management. This scoping review aims to map available evidence about the subject of pessary self-management for POP to identify knowledge gaps providing the basis for future research.

METHODS AND ANALYSIS

The scoping review will be conducted using the Joanna Briggs Institute scoping review methodology and reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines. A search of Medline, CINAHL, Embase and PsycInfo will be undertaken to identify relevant articles which meet the eligibility criteria using the search terms 'pessary' and 'self-management' or 'self-care'. A hand search of the reference list of non-original research identified during the search but excluded, will be conducted for additional publications which meet the inclusion and exclusion criteria. Data relevant to the topic of pessary self-management will be extracted and critical appraisal of all included publications undertaken.

ETHICS AND DISSEMINATION

No ethical or Health Research Authority approval is required to undertake the scoping review. However, it has been registered with The Open Science Framework (DOI 10.17605/OSF.IO/DNGCP). The findings will inform future research exploring pessary self-management and be disseminated via both a presentation at a national conference and publications in peer reviewed journals.

A systematic review of the methods and drugs used for performing suprascapular nerve block injections for the non-surgical management of chronic shoulder pain

Suprascapular nerve block (SSNB) injections are growing in popularity as a treatment option for people with chronic shoulder pain. The optimal method of injection and aftercare is unknown. This review describes the current methods and drugs used for performing SSNB injections in the non-surgical management of adults with chronic shoulder pain in order to inform future research in this area. Systematic searches of CINAHL, MEDLINE (OVID), AMED, Embase databases and the Cochrane Library were undertaken from inception to June 2020. Data on the method and drugs used for injection and aftercare were extracted and summarised for areas of commonality and discrepancy. We included 53 studies in this review. In total, eight different injection methods were reported within the included studies. Indirect surface land-marked methods were the most common method reported in 21 studies. Direct surface land-marked methods were reported in 12 studies. Ultrasound-guided methods used alone were reported in 16 studies. Both fluoroscopy and computed tomography methods used alone were reported in one study each. Electromyography was used in combination with other injection methods in nine studies. Wide variation in the composition of the injectate was observed between studies. Local anaesthetic was used within injectate preparations in all studies. Local anaesthetic used alone was reported in 20 studies, combined with steroid in 29 studies and combined with various other components in 5 studies. Physiotherapy following injection was reported in 26 studies. Reported details of physiotherapy varied considerably. This review identified substantial variation in the methods and drugs used to perform SSNB injection in clinical trials. Current literature demonstrates a wide range of methods used for SSNB injection administration. Consensus research defining standardised practice for SSNB injection is now needed to guide future clinical practice and research.

Use of cast immobilisation versus removable brace in adults with an ankle fracture: multicentre randomised controlled trial

OBJECTIVES

To assess function, quality of life, resource use, and complications in adults treated with plaster cast immobilisation versus a removable brace for ankle fracture.

DESIGN

Multicentre randomised controlled trial.

SETTING

20 trauma units in the UK National Health Service.

PARTICIPANTS

669 adults aged 18 years and older with an acute ankle fracture suitable for cast immobilisation: 334 were randomised to a plaster cast and 335 to a removable brace.

INTERVENTIONS

A below the knee cast was applied and ankle range of movement exercises started on cast removal. The removable brace was fitted, and ankle range of movement exercises were started immediately.

MAIN OUTCOME MEASURES

Primary outcome was the Olerud Molander ankle score at 16 weeks, analysed by intention to treat. Secondary outcomes were Manchester-Oxford foot questionnaire, disability rating index, quality of life, and complications at 6, 10, and 16 weeks.

RESULTS

The mean age of participants was 46 years (SD 17 years) and 381 (57%) were women. 502 (75%) participants completed the study. No statistically significant difference was found in the Olerud Molander ankle score between the cast and removable brace groups at 16 weeks (favours brace: 1.8, 95% confidence interval -2.0 to 5.6). No clinically significant differences were found in the Olerud Molander ankle scores at other time points, in the secondary unadjusted, imputed, or per protocol analyses.

CONCLUSIONS

Traditional plaster casting was not found to be superior to functional bracing in adults with an ankle fracture. No statistically difference was found in the Olerud Molander ankle score between the trial arms at 16 weeks.

TRIAL REGISTRATION

ISRCTN registry ISRCTN15537280.

Magdalenian and Epimagdalenian chronology and palaeoenvironments at Kůlna Cave, Moravia, Czech Republic

Kůlna Cave is the only site in Moravia, Czech Republic, from which large assemblages of both Magdalenian and Epimagdalenian archaeological materials have been excavated from relatively secure stratified deposits. The site therefore offers the unrivalled opportunity to explore the relationship between these two archaeological phases. In this study, we undertake radiocarbon, stable isotope (carbon, nitrogen and sulphur), and ZooMS analysis of the archaeological faunal assemblage to explore the chronological and environmental context of the Magdalenian and Epimagdalenian deposits. Our results show that the Magdalenian and Epimagdalenian deposits can be understood as discrete units from one another, dating to the Late Glacial between c. 15,630 cal. BP and 14,610 cal. BP, and c. 14,140 cal. BP and 12,680 cal. BP, respectively. Stable isotope results (δ¹³C, δ¹⁵N, δ³⁴S) indicate that Magdalenian and Epimagdalenian activity at Kůlna Cave occurred in very different environmental settings. Magdalenian occupation took place within a nutrient-poor landscape that was experiencing rapid changes to environmental moisture, potentially linked to permafrost thaw. In contrast, Epimagdalenian occupation occurred in a relatively stable, temperate environment composed of a mosaic of woodland and grassland habitats. The potential chronological gap between the two phases, and their associations with very different environmental conditions, calls into question whether the Epimagdalenian should be seen as a local, gradual development of the Magdalenian. It also raises the question of whether the gap in occupation at Kůlna Cave could represent a change in settlement dynamics and/or behavioural adaptations to changing environmental conditions.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12520-020-01254-4.

Protocol for a randomised controlled trial of Subacromial spacer for Tears Affecting Rotator cuff Tendons: a Randomised, Efficient, Adaptive Clinical Trial in Surgery (START:REACTS)

INTRODUCTION

Shoulder pain due to irreparable rotator cuff tears can cause substantial disability, but treatment options are limited. A balloon spacer is a relatively simple addition to a standard arthroscopic debridement procedure, but it is costly and there is no current randomised trial evidence to support its use. This trial will evaluate the clinical and cost-effectiveness of a subacromial balloon spacer for individuals undergoing arthroscopic debridement for irreparable rotator cuff tears.New surgical procedures can provide substantial benefit to patients. Good quality randomised controlled trials (RCTs) are needed, but trials in surgery are typically long and expensive, exposing patients to risk and the healthcare system to substantial costs. One way to improve the efficiency of trials is with an adaptive sample size. Such methods are well established in drug trials but have rarely, if ever, been used in surgical trials.

METHODS AND ANALYSIS

Subacromial spacer for Tears Affecting Rotator cuff Tendons: a Randomised, Efficient, Adaptive Clinical Trial in Surgery (START:REACTS) is a participant and assessor blinded, adaptive, multicentre RCT comparing arthroscopic debridement with the InSpace balloon (Stryker, USA) to arthroscopic debridement alone for people with a symptomatic irreparable rotator cuff tear. It uses a group sequential adaptive design where interim analyses are performed using all of the 3, 6 and 12-month data that are available at each time point. A maximum of 221 participants will be randomised (1:1 ratio), this will provide 90% power (at the 5% level) for a 6 point difference in the primary outcome; the Oxford Shoulder Score at 12 months. A substudy will use deltoid-active MRI scans in 56 participants to assess the function of the balloon. Analysis will be on an intention-to-treat basis and reported according to principles established in the Consolidated Standards of Reporting Trials statement.

ETHICS AND DISSEMINATION

NRES number 18/WM/0025. The results will be disseminated via peer-reviewed publications, presentations at conferences, lay summaries and social media.

TRIAL REGISTRATION NUMBER

ISRCTN17825590.

Primary surgical management of anterior pelvic organ prolapse: a systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

Anterior compartment prolapse is the most common pelvic organ prolapse (POP) with a range of surgical treatment options available.

OBJECTIVES

To compare the clinical effectiveness and cost-effectiveness of surgical treatments for the repair of anterior POP.

METHODS

We conducted a systematic review of randomised controlled trials comparing surgical treatments for women with POP. Network meta-analysis was possible for anterior POP, same-site recurrence outcome. A Markov model was used to compare the cost-utility of surgical treatments for the primary repair of anterior POP from a UK National Health Service perspective.

MAIN RESULTS

We identified 27 eligible trials for the network meta-analysis involving eight surgical treatments tested on 3194 women. Synthetic mesh was the most effective in preventing recurrence at the same site. There was no evidence to suggest a difference between synthetic non-absorbable mesh, synthetic partially absorbable mesh, and biological mesh. The cost-utility analysis, which incorporated effectiveness, complications and cost data, found non-mesh repair to have the highest probability of being cost-effective. The conclusions were robust to model inputs including effectiveness, costs and utility values.

CONCLUSIONS

Anterior colporrhaphy augmented with mesh appeared to be cost-ineffective in women requiring primary repair of anterior POP. There is a need for further research on long-term effectiveness and the safety of mesh products to establish their relative cost-effectiveness with a greater certainty.

TWEETABLE ABSTRACT

New study finds mesh cost-ineffective in women with anterior pelvic organ prolapse.

Fetal Heart Rate Deceleration Detection Using a Discrete Cosine Transform Implementation of Singular Spectrum Analysis

Objectives : To develop a singular-spectrum analysis (SSA) based change-point detection algorithm applicable to fetal heart rate (FHR) monitoring to improve the detection of deceleration events.

Methods : We present a method for decomposing a signal into near-orthogonal components via the discrete cosine transform (DCT) and apply this in a novel online manner to change-point detection based on SSA. The SSA technique forms models of the underlying signal that can be compared over time; models that are sufficiently different indicate signal change points. To adapt the algorithm to deceleration detection where many successive similar change events can occur, we modify the standard SSA algorithm to hold the reference model constant under such conditions, an approach that we term “base-hold SSA”. The algorithm is applied to a database of 15 FHR tracings that have been preprocessed to locate candidate decelerations and is compared to the markings of an expert obstetrician.

Results : Of the 528 true and 1285 false decelerations presented to the algorithm, the base-hold approach improved on standard SSA, reducing the number of missed decelerations from 64 to 49 (21.9%) while maintaining the same reduction in false-positives (278).

Conclusions : The standard SSA assumption that changes are infrequent does not apply to FHR analysis where decelerations can occur successively and in close proximity; our base-hold SSA modification improves detection of these types of event series.

Experimental evidence for the co-evolution of hominin tool-making teaching and language

Hominin reliance on Oldowan stone tools-which appear from 2.5 mya and are believed to have been socially transmitted-has been hypothesized to have led to the evolution of teaching and language. Here we present an experiment investigating the efficacy of transmission of Oldowan tool-making skills along chains of adult human participants (N=184) using five different transmission mechanisms. Across six measures, transmission improves with teaching, and particularly with language, but not with imitation or emulation. Our results support the hypothesis that hominin reliance on stone tool-making generated selection for teaching and language, and imply that (i) low-fidelity social transmission, such as imitation/emulation, may have contributed to the ~700,000 year stasis of the Oldowan technocomplex, and (ii) teaching or proto-language may have been pre-requisites for the appearance of Acheulean technology. This work supports a gradual evolution of language, with simple symbolic communication preceding behavioural modernity by hundreds of thousands of years.

Evaluation of digital and skinfold caliper measurements of the Achilles tendon width

Background: A critical review of the literature shows that very few objective methods for clinically evaluating Achilles tendinopathy have been described.

Aim: To evaluate the validity and reliability of common digital and skinfold calipers in measuring the Achilles tendon width.

Methods: Reliability study of ten healthy adult volunteers (five males and five females) was performed at the Rheumatology Unit of Barzilai Medical Center, Ashkelon, Israel. Achilles tendon width was measured by ultrasound at two points of both legs (the tendon attachment and 5 cm proximally). Using regular and skinfold calipers, two further measurements were made, three hours apart, at the same sites.

Results: Test-retest reliability was high for the skinfold caliper at both the upper (intraclass correlation coefficient (ICC)=0.863, p<0.001) and lower (ICC=0.931, p<0.001) points, and moderate for the regular caliper at upper (ICC=0.730, p<0.001) and lower (ICC=0.641, p<0.001) points. Moderate association was found between ultrasound and caliper measurements at the lower point (Spearman's rank correlation coefficient (rho)=0.721, p=0.019 for regular calipers; rho=0.646, p=0.043 for skinfold calipers). At the upper point, the associations were high (rho=0.778, p=0.008 for regular calipers; rho=0.960, p<0.001 for skinfold calipers).

Conclusions: The skinfold caliper showed a higher correlation with ultrasound measurements and higher intraobserver reliability than the regular caliper. Therefore, the skinfold caliper can be recommended in clinics and trials when repeated measurements need to be performed.

'Discovery learning': an account of rapid curriculum change in response to accreditation

BACKGROUND/AIMS

The purpose of this study was to explore the attitudes and experiences of leaders responsible for making rapid changes to a medical school curriculum in response to an adverse accreditation report. The new curriculum was based on the principles of problem-based learning ('Discovery Learning'), with changes to the way that students were assessed.

METHODS

We conducted semi-structured interviews with leaders responsible for education at the school two and a half years after the adoption of the new curriculum. We coded the resulting transcripts to identify major and minor themes expressed by participants.

RESULTS

Thirty-five senior leaders, administrators and course directors were invited for the interview; 14 (40%) were interviewed. Five main themes were noted in the data: (1) organization and control of the curriculum; (2) changes in the practices of teaching and learning; (3) effects on faculty members; (4) sources of resistance and (5) attitudes to curriculum change in general.

CONCLUSION

This study demonstrates that major curriculum change can be achieved successfully in a short period of time. This study also illustrates some of the problems associated with making rapid changes to the medical school curriculum, and highlights the importance of attitudes to change amongst the leadership of a medical school.

The accuracy and inter-observer reliability of acetate templating in total hip arthroplasty

AIM

The accuracy and inter-observer reliability (IOR) of acetate templating on hard copy X-rays in 33 primary total hip arthroplasties as measured by consultant and trainee surgeons was analyzed to find out how accurate are junior surgeons undertaking specialty training.

METHODS

The study was questionnaire-based using a prospective cohort over a 4 weeks period. The Surgeon measurements of acetabular cup, femoral stem and femoral offset sizes were noted following acetate measurements and then compared with the final implant chosen during surgery.

RESULTS

Prediction of sizing to within one size of the final match size was 75% accurate for cup and 91% accurate for femoral stem. Prediction of exact femoral offset sizes was 91% accurate. Templating showed strong IOR between senior consultant surgeon and junior trainee registrar within one size for cup (83%) and stem (100%) and for exact hip offset prediction (92%).

CONCLUSION

We conclude that acetate templating on hard copy X-rays is beneficial to surgeons to gauge acetabular cup and femoral stem size to within one size range. This further helps in predicting nearly exact femoral offset size.

Childbirth after pelvic floor surgery: analysis of Hospital Episode Statistics in England, 2002-2008

OBJECTIVE

To report the numbers of patients having childbirth after pelvic floor surgery in England.

DESIGN

Retrospective analysis of Hospital Episode Statistics data.

SETTING

Hospital Episode Statistics database.

POPULATION

Women, aged 20-44 years, undergoing childbirth after pelvic floor surgery between the years 2002 and 2008.

METHODS

Analysis of the Hospital Episode Statistics database using Office of Population, Censuses and Surveys: Classification of Interventions and Procedures, 4th Revision (OPCS-4) code at the four-character level for pelvic floor surgery and delivery, in women aged 20-44 years, between the years 2002 and 2008.

MAIN OUTCOME MEASURES

Numbers of women having delivery episodes after previous pelvic floor surgery, and numbers having further pelvic floor surgery after delivery.

RESULTS

Six hundred and three women had a delivery episode after previous pelvic floor surgery in the time period 2002-2008. In this group of 603 women, 42 had a further pelvic floor surgery episode following delivery in the same time period. The incidence of repeat surgery episode following delivery was higher in the group delivered vaginally than in those delivered by caesarean (13.6 versus 4.4%; odds ratio, 3.38; 95% confidence interval, 1.87-6.10).

CONCLUSIONS

There were 603 women having childbirth after pelvic floor surgery in the time period 2002-2008. The incidence of further pelvic floor surgery after childbirth was lower after caesarean delivery than after vaginal delivery, and this may indicate a protective effect of abdominal delivery.

A Portable, PC-Based Monitor for Automated, On-line Cardiorespiratory State Classification

We have developed a monitor that acquires, classifies, annotates and displays patient cardiorespiratory data in an on-line and fully automated manner. The monitor is compact, portable and battery-operated; it applies automated methods that detect apnea and classify cardiorespiratory state on-line from non-invasive measurements of patient respiratory movements, blood oxygen saturation and heart rate, logging the raw and processed data. The monitor provides continuous, on-line, objective, standardized cardiorespiratory classification and has a graphical display and interface for patient monitoring by a clinician; it has immediate application in the clinical setting.

High-fat diet alters gene expression in the liver and colon: links to increased development of aberrant crypt foci

BACKGROUND

Obesity is associated with an increased risk of colon cancer. High-fat diets that lead to obesity may be a contributing factor, but the mechanisms are unknown.

AIMS

This study examines susceptibility to azoxymethane (AOM)-induced precancerous lesions in mice in response to consumption of either a low or a high-fat diet and associated molecular changes in the liver and colon.

METHODS

Gene markers of xenobiotic metabolism, leptin-regulated inflammatory cytokines and proliferation were assessed in liver and colon in response to high-fat feeding to determine links with increased sensitivity to AOM.

RESULTS

High-fat feeding increased development of AOM-induced precancerous lesions and was associated with increased CYP2E1 gene expression in the liver, but not the colon. Leptin receptors and the colon stem cell marker (Lgr5) were down-regulated in the proximal colon, with a corresponding up-regulation of the inflammatory cytokine (IL6) in response to high-fat feeding. Notably in the distal colon, where aberrant crypt foci develop in response to AOM, the proliferative stem cell marker, Lgr5, was significantly up-regulated with high-fat feeding.

CONCLUSIONS

The current study provides evidence that high-fat diets can alter regulation of molecular markers of xenobiotic metabolism that may expose the colon to carcinogens, in parallel with activation of β-catenin-regulated targets regulating colon epithelial cells. High-fat diets associated with obesity may alter multiple molecular factors that act synergistically to increase the risk of colon cancer associated with obesity.

Insertional achilles tendinopathy management: a systematic review

BACKGROUND

Achilles tendinopathy is a common problem and its management remains controversial. However, many clinicians consider that the sub-group of patients with insertional Achilles tendinopathy are even more difficult to manage. The aim of this systematic review was to review evidence for interventions specific to insertional Achilles tendinopathy.

MATERIALS & METHODS

Medline and the Cochrane library were searched using a pre-defined search strategy. All study designs were included except case studies, narrative reviews, technical notes and letters/personal opinion. The results were evaluated independently by two reviewers and assessed against the inclusion/exclusion criteria. All included articles were assessed for methodological quality and study characteristics were extracted into a table.

RESULTS

One hundred eighteen articles were identified through the search strategy, of which 11 met the eligibility criteria. Six studies evaluated operative techniques following failed conservative management and five evaluated conservative interventions only. The overall level of evidence was limited to case series evaluations and one randomized controlled trial.

CONCLUSION

There is a consensus that conservative methods should be used before operative interventions. Current evidence for conservative treatment favors eccentric loading and shock wave therapy, although there is limited evidence by which to judge their effectiveness. Evaluation of operative interventions has been mostly retrospective and remains inconclusive.

Laparoscopic uterine sling suspension: a new technique of uterine suspension in women desiring surgical management of uterine prolapse with uterine conservation

The surgical management of uterine prolapse in women who wish to retain their uterus remains a challenge. Several techniques have been reported using open abdominal, laparoscopic and vaginal approaches. The laparoscopic approach offers both excellent intraoperative visualisation of supportive and adjacent structures and quick postoperative recovery. Currently, laparoscopic suspension of the uterus to the round ligaments, uterosacral ligaments, suture and synthetic mesh suspension to the sacral promontory have been reported. This report describes a new surgical technique of laparoscopic uterine suspension, which has been performed successfully in eight women. Mersilene tape is used to suspend the uterus to the sacral promontory bilaterally and to recreate new uterosacral ligaments.

Proportional microvolume capacitive liquid level sensor array

A sensor array has been developed for use with laboratory automation to permit closed-loop control of liquid levels in a multiwell microplate geometry. We extended a simple electrical model for non-contact capacitance-based fluid sensors to describe a fluid-level dependency. The new model shows that a charge-transfer based capacitance transducer, employing a liquid-specific calibration, can be used to obtain an output signal that varies linearly with the liquid level. The calibration also compensates for liquid-to-liquid conductivity and permittivity differences. A prototype 3&#215;3 sensor array was built and tested using NaCl and ethanol solutions to simulate the range of conductivity and permittivity typical in biological and chemical research. Calibrated output signals were linear with liquid volume for all tested solutions (R²&gt;0.92). Measurement error averaged 1.3 % (2.0 &#956;l) with a standard deviation of 6.0% (9.0 &#956;l). These results demonstrate the feasibility of developing a microvolume sensor array in essentially any M&#215;N microplate geometry.

A novel approach to speed up peptide sequencing via MS/MS spectra analysis

In proteomics, tandem mass spectrometry is the key technology for peptide sequencing from the cells. Different methods have been proposed to sequence peptides through tandem mass spectra. While the methods are capable of providing more robust and accurate results, they are also computationally expensive, and create a bottleneck in high throughput peptide identification. In this work, we introduce a novel approach to speedup peptide sequencing. In contrast to the traditional approaches, we conduct coarse comparison of spectral profiles to drastically shrink the size of candidate peptides. A fast algorithm has been developed for this goal. It is shown in our experiments that such an approach can significantly improve the speed for peptide sequencing.

Selecting suspension points and excising the vagina during Michigan four-wall sacrospinous suspension

OBJECTIVE

To describe the variations in the location of the vaginal apex and the length of vagina excised in women undergoing the Michigan four-wall sacrospinous suspension for posthysterectomy vaginal vault prolapse.

METHODS

A prospective observational study of 76 women who had the Michigan modification sacrospinous suspension performed between 1998 and 2001 for posthysterectomy vaginal vault prolapse was carried out. Demographics and preoperative, operative, and postoperative findings were noted, including the pelvic organ prolapse quantification score. The locations of the suspension points relative to the hysterectomy scar were recorded. The amount of vagina excised at surgery and the pre- and postoperative vaginal lengths are reported.

RESULTS

The mean length and standard deviation of vagina excised was 4.6 +/- 2.5 cm. The apex created at sacrospinous fixation was at the hysterectomy scar in only seven women (9%). It was most often situated behind the hysterectomy scar, in 58 cases (76%); it was situated in front of it in 11 (14%). In seven women no vagina was excised, and in the remaining 69 women a mean length of 5.1 +/- 2.2 cm was removed. The mean vaginal lengths were 9.7 +/- 1.7 cm preoperatively and 9.4 cm +/- 0.8 postoperatively, a 0.3-cm difference.

CONCLUSION

When one performs the Michigan modification sacrospinous suspension, the chosen suspension points are often not at the hysterectomy scar, and in women with large prolapses excess vagina frequently is excised without compromising postoperative vaginal length.

Thoracic epidural analgesia via the caudal approach in pediatric patients undergoing fundoplication using nerve stimulation guidance

IMPLICATIONS

Epidural catheter placement using electrical stimulation guidance is an alternative approach for positioning the catheter into the thoracic region via the caudal space. This easily performed clinical assessment provides optimization of catheter tip positioning for achieving effective pain control.

Desmoplastic melanoma

Desmoplastic melanoma is an uncommonly encountered variant of malignant melanoma. Three histological subtypes exist: desmoplastic, neurotropic, and neural transforming. Desmoplastic melanoma commonly presents in conjunction with existing melanocytic lesions or as an amelanotic firm nodule. Local recurrences are common. Thirty patients over a 6-year period were treated at our institution for desmoplastic melanoma. All lesions were treated with local excision. Local recurrence occurred in seven patients (23%) and was treated by aggressive re-excision in each instance. Clinical regional metastasis (lymph nodal basins) were detected in two patients (6%). Distant metastasis (lung) developed in two patients (6%). Twenty-three patients (76%) were found to have desmoplastic subtype, whereas five (17%) had neurotropic subtype. Six patients (20%) had associated pigmented melanotic lesions. Average length of follow-up has been 18 months. Overall survival is 96 per cent. Presentations and histologic diagnosis can sometimes be difficult and misleading. Treatment is aggressive local excision with follow-up necessary to detect resectable recurrent lesions.

An audit of patients investigated by laparoscopy and dye for infertility

We reviewed 100 laparoscopy and dye studies performed in the Coombe Women's Hospital to determine whether recommended guidelines were followed for the investigation of infertility. Individual chart review provided information on patient demographics, preoperative investigations, operative findings and outcome. Preoperative assessment of ovulation or a semen analysis was not performed in 20 and 30 women, respectively. At laparoscopy bilateral tubal patency was demonstrated in 86 patients, three patients had bilateral blocked tubes and 11 patients had unilateral tubal occlusion. In 54% of patients there were no other additional findings. Following laparoscopy five women were referred for in vitro fertilisation and five patients had further surgery as a result of the findings at laparoscopy. In addition, three women were treated for hyperprolactinaemia and three male partners were referred for further investigation. Within one year 20 women became pregnant, 18 delivered a baby and two had a miscarriage.

Confirmation of caudal needle placement using nerve stimulation

BACKGROUND

The study was designed to examine a new method of confirming proper caudal needle placement using nerve stimulation.

METHODS

Thirty-two pediatric patients were studied. A 22-gauge insulated needle was inserted into the caudal canal via the sacral notch until a "pop" was felt. The needle placement was classified as correct or incorrect depending upon the presence or absence of anal sphincter contraction (S2-S4) to electrical simulation (1 to 10 mA).

RESULTS

Three patients were excluded, two because they inadvertently received neuromuscular blockers and one because the patient's anatomy precluded any attempt at a caudal block. The sensitivity and specificity of the test were both 100% in predicting clinical outcomes of the caudal block. Six patients had a negative stimulation test after the first attempt to place the needle. Four of these went on to receive a second attempt of needle insertion after a subcutaneous bulge or resistance to local anesthetic injection were observed. Following needle reinsertion, positive stimulation tests were elicited. These patients received the local anesthetic injection with ease and had good analgesia postoperatively. No attempt was made to reinsert the needle in the remaining two patients with a negative stimulation test, as they did not show subcutaneous bulge or resistance upon injection. These patients had poor analgesia postoperatively. The positive predictive value of the test was greater than the presence of a "pop" alone (P < 0.05) but not significantly different (P = 0.492) over the presence of "pop" and easy injection.

CONCLUSION

This test may be used as a teaching and adjuvant tool in performing caudal block.

Withholding oral fluids from children undergoing day surgery reduces vomiting

The effect of withholding oral fluids on the incidence of postoperative vomiting was evaluated in 317 children undergoing day surgery. Children were randomized by cohort into one of two groups either drinking oral fluids or having oral fluids withhold for 4-6 h postoperatively. All patients received replacement intravenous fluids sufficient to cover the anticipated fasting period. Vomiting was assessed in hospital through to the first postoperative day. Compliance to the protocol was excellent. The incidence of vomiting in the group with fluids withheld was significantly less than (P < 0.004) that of the group which drank (38% vs 56%). This difference was seen whether or not patients thought to be at high risk for postoperative vomiting (strabismus or adenoidectomy +/- tonsillectomy) were included in the analysis. The greatest effect of withholding oral fluids was seen in patients receiving opioids (P < 0.001) where vomiting was reduced from 73% to 36%. Withholding oral fluids postoperatively from children undergoing day surgery reduces the incidence of vomiting.

A rapid precurarization technique using rocuronium

PURPOSE

To evaluate a rapid and time-saving precurarization technique using rocuronium to prevent succinylcholine-induced myalgia.

METHOD

In a prospective, double blind randomized study, 42 ASA 1-2 patients were assigned to one of three pretreatment groups: 0.01 ml.kg-1 normal saline, 0.1 mg.kg-1 atracurium, and 0.1 mg.kg-1 rocuronium. Anaesthesia commenced with 1.5 micrograms.kg-1 fentanyl and 0.5 mg.kg-1 lidocaine at time zero. Pretreatment was administered 60 sec later, followed by 2.5 mg.kg-1 propofol. At 90 sec, 1.5 mg.kg-1 succinylcholine was injected and 30 sec later, the trachea was intubated and the ease of intubation was graded. The patient was observed for the presence and severity of fasciculations. Myalgias were recorded on postoperative days 1, 2 and 7.

RESULTS

The incidence of fasciculations in the rocuronium group (21.4%) was lower (P < 0.001) than atracurium (78.5%) or placebo (92.8%) groups. On postoperative day 1, the incidence of postoperative myalgia in the rocuronium group (14.2%) was less than the placebo group (78.2%; P < 0.002) and atracurium group (85.7%; P < 0.001). The incidence of myalgia in the rocuronium group (7.1%) was lower than in the placebo group (78.5%; P < 0.001) but not different from the atracurium group (42.8%; P = 0.077) on postoperative day 2. On postoperative day 7, there was no difference among the three groups. Fasciculations were related to postoperative myalgia. There was no difference in intubating conditions among the three groups.

CONCLUSION

Rocuronium pretreatment given just before induction of anaesthesia with propofol reduces fasciculations and succinylcholine-induced myalgia.

Extra-abdominal closure of enterocutaneous fistula

Enterocutaneous fistula is a dread complication of gastrointestinal disease and gastrointestinal operation. These patients typically have undergone numerous abdominal operations, often with peritoneal contamination, carcinoma, and/or a history of radiation, making operation for repair daunting, if not impossible. We describe a method for closure of enterocutaneous fistula, which we have used successfully in four such patients. After failure of nonsurgical management, each patient's fistula was closed with a combination of skin, muscle, and fascial flaps after intubation of the fistula with a Malecot catheter. No intra-abdominal dissection was necessary. All fistulas healed completely. We recommend this closure in any patient who has failed surgical or nonsurgical therapy or in whom celiotomy is contraindicated or is to be avoided.

Identification of lymphatic drainage basins in patients with cutaneous melanoma

Lymphoscintigraphy has been shown to be of assistance in predicting lymphatic basins at risk for the development of metastatic disease in patients with cutaneous malignant melanoma. To further establish the efficacy of this method, 212 patients presenting to the H. Lee Moffitt Cancer Center and Research Institute at the University of South Florida with primary melanoma of the head, neck, and trunk have been studied. All patients had clinical stage 1 or 2 melanoma and were candidates for elective lymph node dissection. Drainage patterns identified by lymphoscintigraphy were compared to those predicted by historical anatomical guidelines and were found to be discordant in 63% of patients with tumors of the head and neck, and in 32% of those with primary lesions located on the trunk. Operative intervention was changed because of these findings in 47% of all patients, with 19% undergoing dissection of nonclassical lymph node basins. An additional 28% did not have a node dissection because of failure of the scintigram to demonstrate a predominant drainage basin or the demonstration of multiple drainage sites. After a mean follow-up of 2.8 years, there have been no recurrences in basins not positive by lymphoscintigraphy. The lymphatic drainage from cutaneous melanoma of the head, neck, and trunk cannot be reliably predicted by clinical judgment or classic anatomic guidelines, and lymphoscintigraphy is indicated in these patients prior to elective lymph node dissection.

Blepharoplasty in the patient with exophthalmos

The plastic surgeon performing blepharoplasty should maintain a high degree of surveillance for the presence of exophthalmos. Exophthalmos may be masked by the presence of eyelid compensations and substantial amounts of eyelid fat. The surgeon should know how to detect the condition and measure its extent.

Postural disturbances in paroxysmal positional vertigo

Postural sway was computed in 14 patients suffering from paroxysmal positional vertigo, before and after the paroxysm. In all patients, the nystagmus elicited during the paroxysm was compatible with excitation of the posterior semicircular canal. Patients stood on a force plate for 20 s while the anteroposterior and mediolateral projections of the center of force were recorded and standard deviations computed. Recordings were made after placing the patient's head in the opposite (healthy) and the provocative position. Vertigo was elicited and the nystagmus was observed in 10 of 14 patients. Analysis of the sway data in these patients (N = 10), using the Wilcoxon matched pairs test, showed that the mediolateral sway remained unchanged, while the anteroposterior sway increased, following the provocative maneuver (p less than 0.01). It is concluded that paroxysmal positional vertigo, in which the elicited nystagmus is compatible with excitation of the posterior semicircular canal, increases the anteroposterior rather than the mediolateral sway immediately following the paroxysm.

Immunity in Pekin ducks experimentally and naturally infected with duck hepatitis B virus

The immune response to duck hepatitis B virus (DHBV) had not been elucidated. An assay was therefore established to detect the presence of antibody to DHB surface antigen (anti-DHBs) in serum of experimentally inoculated and naturally infected ducks. Anti-DHBs in serum was detected by indirect RIA from the percentage inhibition of binding of rabbit anti-DHBs to purified DHBsAg. Specificity was confirmed by positive and negative controls, infected and noninfected sera, and a mouse monoclonal antibody to DHB core antigen (anti-DHBc). Serum and liver samples were tested for DHBV DNA by dot-blot hybridization assay. Adult ducks repeatedly inoculated with DHBV remained non-viraemic but developed anti-DHBs. This antibody activity neutralized the infectivity of DHBV, which was experimentally inoculated into 1-day-old ducklings. In naturally infected flocks anti-DHBs was detected in a proportion of noninfected adult ducks as well as 1-day-old hatchlings. Anti-DHBs activity in hatchlings neutralized the infectivity of experimentally inoculated DHBV. Pekin ducks can therefore mount a neutralizing antibody response to DHBV, and immunity may be transferred in ovo from dam to off-spring.

Modulation of anti-tumour immunity and the effect of bacterial endotoxin on the growth of different syngeneic tumours from small inocula in mice

Studies were undertaken to determine the influence of E. coli lipopolysaccharide (LPS) on the growth of various doses of two antigenically-distinct syngeneic murine fibrosarcomas designated H1 and H7. The 'weakly' antigenic H1 tumour injected subcutaneously (s.c.) along the abdominal wall was profoundly susceptible to the growth-potentiating effects of a single intraperitoneal (i.p.) injection of 2 micrograms LPS, administered concurrently. 'Sneaking through' effects in control mice were observed with doses of 10 and 100 H1 tumour cells. Rejection of medium-sized inocula 25 or 500 H1 tumour cells were abolished by the administration of LPS. In contrast, the 'strongly' antigenic H7 tumour did not exhibit the 'sneaking through' phenomenon and its growth was only temporarily affected by LPS. Studies were also performed to determine the effect of LPS on the kinetics of delayed-type hypersensitivity (DTH) induced by mitomycin C-treated (MCT) H1 or H7 tumour cells inoculated s.c. into the footpads of mice. The 'strongly' antigenic MCT H7 tumour cells induced consecutive waves of footpad swelling of diminishing intensity and corresponded to periods of anti-tumour resistance. The specific phase of MCT H7-induced footpad swelling, maximal at day 6, was delayed in its induction if LPS was administered concurrently with MCT H7 tumour cells. In contrast, the 'weakly' antigenic MCT H1 tumour cells induced only one specific phase of footpad swelling which was rapidly down-regulated. The induction of immunity by MCT H1 tumour cells was also delayed by the concomitant administration of LPS. Because the 'weakly' antigenic H1 tumour was unable to sustain consecutive waves of anti-tumour immunity, the delay in the expression of such immunity by LPS allowed the H1 tumour cells to multiply to eventually overwhelm a rapidly down-regulated immune response. In contrast, the incidence of tumours arising from the 'strongly' antigenic H7 tumour cells was not significantly affected in LPS-treated mice because the tumour cells which escaped the first encounter with delayed anti-tumour immunity, succumbed to subsequent waves of resistance in both normal and LPS-treated mice injected with fewer than 1 X 10(5) H7 tumour cells.

The role of a functionally distinct IgM anti-type III pneumococcal polysaccharide (SIII) in low-dose paralysis to SIII in mice

Prior treatment (priming) with a weakly immunogenic dose of Type III pneumococcal polysaccharide (SIII) results in the development of an antigen-specific state of unresponsiveness termed low-dose paralysis which is believed to be mediated by suppressor T cells. The present findings show that the passive administration of functionally distinct non-complement-fixing (NCF) IgM anti-SIII antibodies either in monoclonal form or from protein-A absorbed immune serum could significantly suppress the direct plaque-forming cell (PFC) response to an immunogenic dose of SIII administered concurrently. The degree of suppression was comparable with that induced by low-dose paralysis. Low-dose paralysis was consistently induced in athymic (nude) mice 4 days, but not 3 days, after priming with a low dose of SIII, and was associated with the delayed appearance of NCF-IgM anti-SIII in the serum of athymic mice. In contrast, low-dose paralysis was readily induced in normal BALB/c mice 3 days after priming when NCF-IgM anti-SIII antibodies were present. Comparable inhibiton of the direct anti-SIII PFC response was observed when Concanavalin A (Con A) or NCF-IgM anti-SIII serum was administered with SIII antigen. That Con A and NCF-IgM anti-SIII together did not produce additive suppression was attributed to the adsorption of NCF-IgM anti-SIII antibodies to Con A. Complement-dependent single radial haemolysis mediated by CF hybrid IgM/A or CF-IgM anti-SIII serum was blocked by monoclonal NCF-IgM or IgA anti-SIII antibodies and indicated that each of the antibodies was specific for the same SIII-determinant. Evidence is presented to show that low-dose paralysis in the CF-IgM response to SIII is not mediated by suppressor T cells but can be attributed to highly avid NCF-IgM anti-SIII antibodies, formed preferentially to low doses of SIII, being able to reduce the immunogenicity of SIII administered subsequently. We propose that low-dose paralysis to SIII is the result of an immunobiological function of highly avid NCF-IgM anti-SIII antibodies which not only confer resistance against capsulated pneumococci but preferentially bind soluble SIII-antigen to reduce its immunogenicity and thereby protect specific CF-IgM positive B cells from being rendered tolerant by direct contact with higher doses of SIII antigen.

Blocking of IgM-mediated single radial haemolysis by IgA and non-complement-fixing IgM anti-type-III pneumococcal antibodies

The results reported here provide information on the effects of mouse non-complement-fixing (NCF) IgM anti-type-III pneumococcal polysaccharide (SIII) in blocking single radial haemolysis (SRH) mediated by complement-fixing (CF) IgM or CF hybrid IgM/A anti-SIII antibodies. The results consistently showed that highly avid NCF IgM or IgA anti-SIII antibodies could prevent the detection of CF IgM or CF IgM/A anti-SIII antibodies by SRH. The altered haemolysis produced by NCF IgM and IgA antibodies in the primary response is similar to that reported when the SRH test was used to screen for primary rubella infection. The findings indicate that false-negative results can be due to the early production of NCF IgM antibodies which can block the detection of CF IgM antibodies particularly if the erythrocytes are coated suboptimally with antigen.

Regulation of immunity and tolerance to type III pneumococcal polysaccharide (SIII) by functionally distinct IgM anti-SIII antibodies

When BALB/c mice and athymic (nude) mice are injected intraperitoneally (i.p.) with pneumococcal type III polysaccharide (SIII), their antibodies as measured by passive haemagglutination (HA) are inhibited more easily by high doses of SIII than antibody measured by passive haemolysis (HL). The HA activity, due mainly to a highly avid non-complement-fixing (NCF) type of IgM, was further distinguished from the HL activity (CF-IgM, or CF-IgM plus CF hybrid IgM/A anti-SIII antibodies) by the failure of the NCF-IgM anti-SIII to bind to protein-A of Staphylococcus aureus (Sa). High-dose tolerance in the HL anti-SIII antibody response of BALB/c and athymic mice was induced only in the absence of circulating NCF-IgM anti-SIII antibodies. The presence of NCF-IgM anti-SIII antibodies formed to multiple daily increasing amounts of SIII, commencing with 0.01 micrograms SIII, decreased the magnitude of the HL anti-SIII response to subsequent daily increments of SIII antigen injected into BALB/c and athymic (nude) mice. Thus, the effect on the HL anti-SIII response was independent of T-cells. The concomitant administration of NCF-IgM anti-SIII rendered SIII less tolerogenic in primed mice. In contrast to the HL activity, the NCF-IgM anti-SIII antibodies were induced to low doses of SIII, conferred protection against viable pneumococci, but did not precipitate the soluble antigen in agar. It is proposed that immune paralysis (as defined by the failure of SIII-injected mice to resist pneumococcal challenge) is not necessarily a condition of total unresponsiveness but is due to an absence of protective NCF-IgM anti-SIII antibodies. Thus, immune paralysis can co-exist with either the presence or absence of non-protective CF-IgM or CF-IgM/A anti-SIII antibodies.

Serum IgM/A, IgA and functionally distinct IgM anti-type III pneumococcal polysaccharide (SIII) antibodies in BALB/c and athymic (nude) mice

The influence of hereditary absence of thymus upon the synthesis of IgA, complement-fixing (CF) hybrid IgM/A, CF-IgM and non-CF-IgM antibodies to pneumococcal type III polysaccharide (SIII) injected into BALB/c and athymic nude mice was studied. Techniques involved the differential absorption of the serum antibodies by protein-A of Staphylococcus aureus (Sa), coprecipitation in gels with 125I-SIII and autoradiography. IgM/A anti-SIII activity was not demonstrable in nude mice but was produced in significant amounts, by day 5, in BALB/c mice injected with SIII. By day 8, nude mice produced more IgA anti-SIII antibodies than BALB/c mice injected with the same antigen. IgA anti-SIII antibodies were not detected in either strain 5 days after SIII administration. The absence of hybrid IgM/A anti-SIII antibodies in athymic mice, prior to the appearance of monotypic IgA anti-SIII antibodies at day 8, suggests that IgM/A and not IgA synthesis is largely T cell-dependent. The evidence also implies that hybrid IgM/A antibody production, maximal on day 5 in BALB/c mice, and absent from nude mice, is not an essential product in the switching from IgM to IgA synthesis. Both strains of mice produced comparable amounts of complement-fixing (CF)-IgM and NCF-IgM anti-SIII antibodies, with the production of non-complement-fixing (NCF)-IgM anti-SIII in athymic mice being delayed. Results indicate that attempts to quantitate the levels of IgA by assays incorporating anti-IgA anti-sera may be complicated by the presence of IgM/A hybrid antibody.(ABSTRACT TRUNCATED AT 250 WORDS)