Sensitivity and specificity of anthropometrics for the prediction of diabetes in a biracial cohort

OBJECTIVE

To evaluate the ability of body mass index, waist circumference, waist-to-hip ratio, and combinations of these variables to discriminate individuals who will develop diabetes in adulthood.

RESEARCH METHODS AND PROCEDURES

Data were from 45- to 64-year-old men and women who were members of the Atherosclerosis Risk in Communities cohort. The analysis sample consisted of 12,814 African American and white participants who were free of diabetes at baseline. Body mass index, waist circumference, waist-to-hip ratio, and diabetes incidence (defined as one glucose measure > or =126 mg/dL after fasting for at least 8 hours, one nonfasting glucose measure > or =200 mg/dL, and self-report of diabetes or report of taking medication for diabetes).

RESULTS

1515 new cases of diabetes were identified over the 9-year follow-up. Areas under receiver operating characteristic curves ranged from 0.66 to 0.73 for single measures. The curves were smooth, with no indication of a threshold. Waist tended to have the highest receiver operating characteristic statistic in all groups, but differences were small.

DISCUSSION

The three anthropometric indices tested were approximately equivalent in their ability to predict diabetes. Sensitivity and specificities differed among ethnic and gender groups.

State of the art neonatal hearing screening with auditory brainstem response

The purpose of this paper is to briefly review some of the aspects of the auditory brainstem response (ABR) that are important in its use as a method of screening and assessing hearing in the neonate. The paper starts by considering the technical limitations of click ABR and explores the alternative electrophysiological methods. It then considers where ABR is required in the screening of neonates. The role of bone conduction ABR in estimating the conductive component of any hearing loss is discussed. Finally, the ability of the neonatal ABR to predict the long-term audiometric outcome of permanently hearing-impaired children is considered.

Patterns of long-term change in body composition are associated with diet, activity, income and urban residence among older adults in China

Studies describing patterns of long-term change in body composition are lacking. Using longitudinal data on 608 healthy, nonobese Chinese (aged 50-70 y) from the 1993 and 1997 China Health and Nutrition Surveys, this article describes the prevalence, sociodemographic and lifestyle correlates of patterns of long-term change in midarm muscle area (MAMA) and body fat (waist circumference). All patterns of change (loss, maintenance [Delta < 1.3 cm(2)], or gain of MAMA with concurrent loss, maintenance [Delta < 2 cm(2)] or gain of body fat), were observed for this sample. After controlling for sex, baseline age, urban residence, height, weight, income, MAMA, waist circumference, smoking status, activity level, mean daily energy and protein intakes (from three 24-h recalls), and change in height, it was determined that subjects who lost both arm muscle and body fat were distinguished from subjects who lost arm muscle but gained body fat by lower income and energy intake at baseline. Although protein intakes at baseline did not differ between the groups that lost arm muscle, protein intakes were significantly higher for subjects who gained both muscle and fat. Patterns of change involving gains in arm muscle were associated with increased protein intake, urban residence, as well as moderate or heavy levels of physical activity at baseline. Variation in protein intake, physical activity, and urban residence also differentiated between the groups that gained fat. Patterns of age-related change in body composition appear associated with modifiable variables, including income, urban residence, activity and protein and energy intake.

Preimplantation genetic diagnosis of pericentric inversions

Inversions are structural chromosome abnormalities that may be associated with infertility, multiple miscarriage and chromosomally unbalanced offspring. Preimplantation genetic diagnosis (PGD) with subtelomeric probes was used to select for transfer only those embryos that were normal or balanced for three pericentric inversions. In contrast to previous protocols the present procedure allows the detection of unbalanced embryos that might arise from U-recombination in the inverted region. Additionally, aneuploidy screening was carried out in two cases by a second round of fluorescent in situ hybridization (FISH) with centromeric probes. Of the three couples that underwent the procedure one became pregnant twice. The first pregnancy delivered a healthy and chromosomally normal baby and the second pregnancy is ongoing with triplets.

The use of electrical stimulation to increase quadriceps femoris muscle force in an elderly patient following a total knee arthroplasty

BACKGROUND AND PURPOSE

Persistent residual quadriceps femoris muscle force deficits after total knee arthroplasty (TKA) are commonly reported and can prevent patients from returning quickly and fully to functional activities. Neuromuscular electrical stimulation offers a potentially more effective means of increasing muscle force than current rehabilitation protocols.

CASE DESCRIPTION

The patient was a 66-year-old man. Neuromuscular electrical stimulation for increasing quadriceps femoris muscle force was initiated 3 weeks after TKA for 11 sessions to supplement stretching exercises and a high-intensity volitional strengthening program.

OUTCOME

The patient's isometric quadriceps femoris muscle force increased from 50% (involved/uninvolved) at 3 weeks after surgery to 86% at 8 weeks after surgery. A concurrent increase in his uninvolved quadriceps femoris muscle force concealed the patient's true increase in his involved quadriceps femoris muscle force in a side-to-side comparison. The patient's final involved quadriceps femoris muscle force (10 weeks after surgery) was 93% of the initial uninvolved quadriceps femoris muscle force.

DISCUSSION

Our patient was able to return to independent activities of daily living and recreational activities, with force gains that surpassed those reported in the literature.

The possible effects on health, comfort and safety of aircraft cabin environments

A consultation was undertaken to investigate the views and concerns of stakeholders in the aircraft industry about the possible harmful effects on personal health, comfort and safety of aircraft cabin environments. Stakeholders were identified from a variety of sources including Government agencies, the Internet, House of Lords inquiry, and suggestions of interviewees. They represented: aircraft crews, aircraft constructors and engineers, government departments and authorities, holiday/flight companies, insurance companies, non-governmental organisations, occupational health physicians, passenger representatives, and independent researchers and consultants. Eighty-seven were contacted of which 57 were interviewed over the telephone using a semi-structured questionnaire. Their concerns were transcribed into a standard format and analysed qualitatively. Key stakeholders, along with Government officials, were invited to a workshop to discuss and prioritize the issues raised during the interviews. The main concerns expressed by the participants fell into five main areas: deep vein thrombosis, air quality, infection, cosmic radiation, and jet lag and work patterns. In addition, a number of safety concerns were raised as well as comments on the provision of appropriate advice to passengers. It was generally felt that further research was required on each of these subjects, as well as an improvement in the quality, quantity and availability of information provided for passengers prior to boarding a flight.

Survey of PCDD/Fs and non-ortho PCBs in UK sewage sludges

A survey of PCDD/F and non-ortho PCB concentrations in the mesophilic, anaerobically digested sludge of 14 UK wastewater treatment works was carried out. The range of total Cl1-Cl8DD/F concentrations in the sludges was 8880-428000 pg/g dw with a median of 23300 pg/g dw. The concentrations of the three non-ortho PCBs were in the range 272-63000 pg/g dw with a median of 695 pg/g dw. The PCDD/F I-TEQs of the sludges studied were comparable to those published in the literature with a range of 20-225 pg I-TEQ/g dw and a median of 40.4 pg/g dw. The non-ortho PCBs usually added 2-7 pg/g to the total TEQ with one notable exception which increased the TEQ value 20-fold. With three exceptions, the PCDD/F content of the sludges fell well below the draft EU limit values proposed on 27 April 2000. The homologue group pattern of the PCDD/Fs is dominated by the HpCDDs and OCDD and is consistent with that found in most sewage sludges. There appears to be no correlation between the degree of industrial input and the PCDD/F concentration. This suggests that trade effluent is not always the most significant source of PCDD/Fs to wastewater in the UK.

Genetic relationships between blowflies (Calliphoridae) of forensic importance

Phylogenetic relationships among blowfly (Calliphoridae) species of forensic importance are explored using DNA sequence data from the large sub-unit (lsu, 28S) ribosomal RNA (rRNA) gene, the study includes representatives of a range of calliphorid species commonly encountered in forensic analysis in Britain and Europe. The data presented provide a basis to define molecular markers, including the identification of highly informative intra-sequence regions, which may be of use in the identification of larvae for forensic entomology. Phylogenetic analysis of the sequences also provides new insights into the different evolutionary patterns apparent within the family Calliphoridae which, additionally, can provide a measure of the degree of genetic variation likely to be encountered within taxonomic groups of differing forensic utility.

Toward an understanding of the furoxan-dinitrosoethylene equilibrium

The tautomerism of furoxan (1,2,5-oxadiazole-2-oxide) has been investigated by different computational methods comprising modern density functionals as well as single-reference and multi-reference ab initio methods. The ring-opening process to 1,2-dinitrosoethylene is the most critical step of the reaction and cannot be treated reliably by low-level computations. The existence of cis-cis-trans-1,2-dinitrosoethylene as a stable intermediate is advocated by perturbational methods, but high-level coupled-cluster calculations identify this as an artifact. In contrast to the analogous reaction in benzofuroxans, cis-cis-cis-1,2-dinitrosoethylene was found to be a transition state rather than a local minimum. Model potentials were used to explain the occurrence and the disappearing of transition states and local minima relative to the reaction of benzofuroxan. Low-lying triplet states that can be accessed due to spin-orbit coupling were investigated as taking part in alternative routes to a proposed singlet pathway. Barriers for rotations of the nitroso groups on the S(0) and T(1) surfaces are reported.

Calreticulin, PDI, Grp94 and BiP chaperone proteins are associated with retained COMP in pseudoachondroplasia chondrocytes

Cartilage oligomeric matrix protein (COMP), a large pentameric glycoprotein and member of the thrombospondin (TSP) group of extracellular proteins, is found in the territorial matrix surrounding chondrocytes. More than 50 unique COMP mutations have been identified as causing two skeletal dysplasias: pseudoachondroplasia (PSACH); and multiple epiphyseal dysplasia (EDM1). Recent studies suggest that calcium-binding and calcium-induced protein folding differ between wild type and mutant proteins, and abnormal processing of the mutant COMP protein contributes to the characteristic enlarged lamellar appearing rER cisternae in PSACH and EDMI chondrocytes in vivo and in vitro. Towards the goal of delineating the pathogenesis of PSACH and EDM1, in-vivo PSACH growth plate and in-vitro PSACH chondrocytes cultured in alginate beads were examined to identify and localize the chaperone proteins participating in the processing of the retained extracellular matrix proteins in the PSACH rER. Aggrecan was localized to both the rER cisternae and matrix while COMP and type IX collagen were only found in the rER. Type II collagen was solely found in the ECM suggesting that it is processed and transported differently from other retained ECM proteins. Five chaperone proteins: BiP (Grp78); calreticulin (CRT); protein disulfide (PDI); ERp72; and Grp94, demonstrated immunoreactivity in the enlarged PSACH cisternae and the short rER channels of chondrocytes from both in-vivo and in-vitro samples. The chaperone proteins cluster around the electron dense material within the enlarged rER cisternae. CRT, PDI and GRP94 AB-gold particles appear to be closely associated with COMP. Immunoprecipitation and Western blot, and Fluorescence Resonance Energy Transfer (FRET) analyses indicate that CRT, PDI and GRP94 are in close proximity to normal and mutant COMP and BiP to mutant COMP. These results suggest that these proteins play a role in the processing and transport of wild type COMP in normal chondrocytes and in the retention of mutant COMP in PSACH chondrocytes.

Weight loss attempts and attitudes toward body size, eating, and physical activity in American Indian children: relationship to weight status and gender

OBJECTIVE

This study examined dieting, weight perceptions, and self-efficacy to eat healthy foods and engage in physical activity and their relationships to weight status and gender among American Indian elementary schoolchildren.

RESEARCH METHODS AND PROCEDURES

Data for this study were collected as part of the baseline examination for the Pathways study. Participants were 1441 second- through third-grade American Indian children in 41 schools representing seven tribes in Arizona, New Mexico, and South Dakota who filled out a questionnaire and had heights and weights taken.

RESULTS

Forty-two percent of the children were overweight or obese. No differences were found between overweight/obese and normal weight children for healthy food intentions or self-efficacy. Heavier children (especially those with body mass index > 95th percentile) were more likely to have tried to lose weight or were currently trying to lose weight. No gender differences were found. Normal weight children chose a slightly heavier body size as most healthy compared with overweight/obese children.

DISCUSSION

The results indicate that children are concerned about their weight and that weight modification efforts are common among overweight American Indian children. School, community, and family-based programs are needed to help young people adopt lifelong healthful eating and physical activity practices.

Changes in body mass index prior to baseline among participants who are ill or who die during the early years of follow-up

The association between body mass index (weight (kg)/height (m)(2)) and mortality may be confounded by preexisting illness. A method commonly used to control for this confounding is the exclusion of participants who have certain diseases at baseline and/or those who die during the early years of follow-up. The authors used data from the Atherosclerosis Risk in Communities (ARIC) Study (n = 14,088) to determine whether participants identified by these criteria had different changes in body mass index than other participants. Weight change was measured over a 3-year interval between study entry (1987-1989) and reexamination (1990-1993), and information on vital status was collected over the subsequent 5 years. Mean change in body mass index was -0.54 (95% confidence interval (CI): -0.90, -0.12) among participants who died in the first year of follow-up, -0.03 (95% CI: -0.18, 0.12) among those who died in the first 4 years of follow-up, and 0.36 (95% CI: 0.33, 0.39) among those who survived for at least 5 years. Participants who died during the first 4 years were over twice as likely as survivors to have changed from the obese category (body mass index >or=30) to the nonobese category (odds ratio = 2.14; 95% CI: 1.44, 3.17). Mean change in body mass index prior to baseline was not different among ill participants compared with those who were healthy, but the odds of converting from obese to nonobese were higher in ill participants than in healthy ones (odds ratio = 1.29; 95% CI: 1.01, 1.67).

Siah-1 mediates a novel beta-catenin degradation pathway linking p53 to the adenomatous polyposis coli protein

The adenomatous polyposis coli (APC) tumor-suppressor protein, together with Axin and GSK3beta, forms a Wnt-regulated signaling complex that mediates phosphorylation-dependent degradation of beta-catenin by the proteasome. Siah-1, the human homolog of Drosophila seven in absentia, is a p53-inducible mediator of cell cycle arrest, tumor suppression, and apoptosis. We have now found that Siah-1 interacts with the carboxyl terminus of APC and promotes degradation of beta-catenin in mammalian cells. The ability of Siah-1 to downregulate beta-catenin signaling was also demonstrated by hypodorsalization of Xenopus embryos. Unexpectedly, degradation of beta-catenin by Siah-1 was independent of GSK3beta-mediated phosphorylation and did not require the F box protein beta-TrCP. These results indicate that APC and Siah-1 mediate a novel beta-catenin degradation pathway linking p53 activation to cell cycle control.

Long-term retrograde amnesia...the crucial role of the hippocampus

For patients with hippocampal pathology, disagreement exists in the literature over whether retrograde amnesia is temporally limited or very extensive depending on whether the anatomical damage is restricted to this structure or also involves additional temporal cortex. We report a comprehensive assessment of retrograde and anterograde memory functions of a severely global amnesic patient (VC). We found that he presented with a remarkably extensive and basically ungraded retrograde amnesia. This impairment profoundly affected four decades preceding the onset of his amnesia and encompassed both non personal and personal facts and events. VC also presented with a severe anterograde amnesia and a deficit in the acquisition of new semantic knowledge in the post-morbid period. Detailed MRI volumetric measurements revealed gross abnormalities in both hippocampi which were markedly shrunken. Of relevance to the debate on retrograde amnesia were the observations that the volumes of both entorhinal cortices and the remainder of both temporal lobes were normal. These data suggest that the hippocampus is critical not only for the efficient encoding and hence normal recall of new information but also for the recall of episodic information acquired before the onset of amnesia. Our results are compatible with the view that retrograde amnesia is both extensive and ungraded when the damage is limited to the hippocampus.

Clinical and radiological correlates of severity and surgery-related outcome in cervical spondylosis

OBJECT

The aim of this study was to determine if radiological features could be used to predict outcome in patients with cervical spondylotic myelopathy (CSM).

METHODS

The authors studied 69 patients consecutively referred to The National Hospital, Queen Square, for decompressive surgery. Data obtained from preoperative cervical spine magnetic resonance (MR) imaging studies were each analyzed on two separate occasions by two blinded radiologists. The parameters determined were signal change and the presence and severity of compression. Clinical outcome was determined by pre- and postoperative timed walks, as well as by evaluation of myelopathy disability index scores, Ranawat classification, and Nurick grades. There was good inter- and intraobserver reliability for determination of radiological data. A significant relationship was found between MR imaging signal change and surgery-related outcome, as reflected by improvement in walking parameters; however, this was confounded by the fact that signal change also related to preoperative walking parameters, and those patients for whom preoperative walking function was worse experienced greater functional improvement in walking postoperatively. The relationships between ambulatory-related data and severity or extent of spinal cord compression were less marked.

CONCLUSIONS

Cervical cord compression and intrinsic MR imaging signal change correlate with clinical severity, and, in this population, the presence of signal change was correlated with better surgery-related outcome. However, confounding factors and the lack of strong correlation indicate that these radiological measurements are insufficient to be used as a reliable tool for predicting surgery-related benefits in individual patients.

Generating theory from the client's experience of same day laparoscopic sterilisation

A grounded theory methodology was used to generate theory about the experiences of women undergoing laparoscopic sterilisation in a day surgery unit. Theories were developed on the role of client education in relieving anxiety, and the importance of privacy in all stages of client care. The grounded theory approach offered a client-centered model for day surgery planning.

Challenges with studies investigating longevity of dental restorations--a critique of a systematic review

OBJECTIVES

A systematic review is a method of evaluating the published and unpublished literature relating to a specific area or topic. The objectives of this paper are to identify and discuss problems encountered in synthesising the available literature; and to make recommendations for the future conduct and reporting of clinical trials that aim to determine the longevity of dental restorations.

DATA SOURCES

Studies were identified by a wide search of published and unpublished material in any language using a large number of general and specialist data bases, hand searching of key dental journals and searching of abstracts from conference proceedings.

STUDY SELECTION

Pre-defined inclusion criteria based on objective outcome measures of restoration longevity and study designs were applied to determine study selection.

CONCLUSIONS

A review of the longevity of dental restorations completed recently encountered substantial problems in designing an appropriate protocol to address this issue. The review found that many of the factors reported previously as affecting restoration longevity could not be confirmed using the agreed systematic review protocol that incorporated an objective study design. Further, the multiplicity of study designs, and reporting methods found in the literature made meta-analyses impossible. A proforma is proposed in order to aid the design of future research into the longevity of restorations.

Performance of neonatal and infant hearing screens: sensitivity and specificity

The terms 'sensitivity' and 'specificity' are defined and some of the factors that determine their values are discussed in the context of screening for permanent childhood hearing loss. There is a need to distinguish between the values observed in 'simple experiments' and those that may be obtained under more realistic 'field' conditions. It is not feasible to give a meta-analytic overview of published data because of the variety of methods and objectives used in those studies published in the literature. However, a qualitative synthesis of the data is possible. This suggests that most proposed neonatal hearing screening tests, when implemented in accordance with a programme of quality assurance, can be reasonably accurate at a modest cost. However, the optimal combination of tests and test parameters for given populations has not yet been fully researched. The infant distraction test screen has a lower sensitivity than neonatal hearing screening tests, particularly for moderate impairments, accompanied by a fairly low specificity.

Development and reliability of a Telephone-Administered Perceived Racism Scale (TPRS): a tool for epidemiological use

The conceptualization of perceived racism as a chronic stressor is relatively new to epidemiology. The Telephone-Administered Perceived Racism Scale (TPRS) captures the complexity of racism within five scales: Experience of Racism (by Blacks as a group and by the respondent), Emotional Responses, Behavioral Responses, Concern for Child(ren), and Past Experiences of Racism. The TPRS was developed for employed Black women. Exploratory factor analyses and tests of internal consistency were completed with 476 Black women, aged 36-53. Factor analyses on their responses to racism yielded five factors: passive emotions, active emotions, passive behaviors, internal active behaviors, and external active behaviors. Alpha reliability values ranged from 0.75 to 0.80 for the active and passive emotions subscales, from 0.59 to 0.69 for the passive behaviors subscale, and greater than 0.76 for both active behaviors subscales. Alpha reliabilities were 0.82, 0.90, 0.88, and 0.82 for Past Experiences, Concern for Child(ren), Experience of Racism--Personal, and Experience of Racism--Group, respectively. Another 30 Black women were queried for test-retest reliability, with values ranging from 0.61 to 0.82. The TPRS was found to be reliable and should serve as a useful epidemiological tool in the examination of the effects of perceived racism on Black women's health.

Two different, highly exposed, bulged structures for an unusually long peptide bound to rat MHC class I RT1-Aa

The rat MHC class Ia molecule RT1-Aa has the unusual capacity to bind long peptides ending in arginine, such as MTF-E, a thirteen-residue, maternally transmitted minor histocompatibility antigen. The antigenic structure of MTF-E was unpredictable due to its extraordinary length and two arginines that could serve as potential anchor residues. The crystal structure of RT1-Aa-MTF-E at 2.55 A shows that both peptide termini are anchored, as in other class I molecules, but the central residues in two independent pMHC complexes adopt completely different bulged conformations based on local environment. The MTF-E epitope is fully exposed within the putative T cell receptor (TCR) footprint. The flexibility demonstrated by the MTF-E structures illustrates how different TCRs may be raised against chemically identical, but structurally dissimilar, pMHC complexes.

Long-term clinical experience with the EGM width detection criterion for differentiation of supraventricular and ventricular tachycardia in patients with implantable cardioverter defibrillators

Inappropriate therapy by ICDs due to SVTs is an important problem. A third generation ICD with a new detection criterion ("EGM width criterion") for differentiation of SVTs and VTs by measuring the width of the intracardiac EGM was studied in 47 patients. A wide EGM was defined as the longest measured EGM plus 4-12 ms (programmed as EGM width threshold). EGM width detection function was programmed to the "Passive" mode so that no therapy was withheld. During a follow-up of 29.9 +/- 8.3 (12-45) months, 489 spontaneous episodes were analyzed. SVTs occurred in ten patients with 305 episodes; 301 were correctly classified by use of the new detection criterion. In four patients four episodes were incorrectly detected as wide QRS tachycardias. Thus specificity for SVT was 98.7% (on a per episode basis) and 60% on a per patient basis. Of 184 VTs in 23 patients, 118 episodes were correctly classified (19 patients), however, in 4 patients 66 VTs were falsely detected as SVTs, 62 (94%) of which occurred in 1 patient with complete left BBB and continuously increasing QRS width in 12-lead surface ECGs. Overall sensitivity (on a per episode basis) for VT detection was 64.1% and 96.7% in patients with stable width of the QRS complex in a 12-lead surface ECG. These data show that this criterion is not superior to data on rate dependent detection criteria and furthermore not applicable in patients with complete BBB.

Obesity and mortality in African-Americans

The Cancer Prevention Study II indicated that obesity might be associated with a smaller increase in the relative rate of mortality in African-Americans compared with whites. The absolute death rate in obese whites, however, was not higher than in obese African-Americans. Avoidance of obesity remains sound advice.

Incidence and outcome of pauci-immune rapidly progressive glomerulonephritis in Wessex, UK: a 10-year retrospective study

BACKGROUND

The Wessex Renal Unit serves a large stable population (2.5 million). Pauci-immune rapidly progressive glomerulonephritis (RPGN) is a frequent cause of acute renal failure requiring admission to our unit ( approximately 8%). At a population level, little is known of the epidemiology and outcome of RPGN.

METHODS

Between 1 April 1986 and 31 March 1996, 141 cases of biopsy proven pauci-immune RPGN were seen in the Wessex region. The records of 128 patients were reviewed. Median (range) follow-up was 1.8 (0.9-9.64) years from diagnosis.

RESULTS

The incidence of 4 per million was stable throughout the period. No clustering was seen. The diagnosis was made (median, 25th, 75th centile) 78.5 (45, 166) days after symptom onset. Co-morbidity (mostly hypertension) was seen in 47% of patients. Other organs affected were lungs 63%, nose/sinuses 50%, joints 42%, muscle 33%, skin 22% and nervous system 14%. Anti-neutrophil cytoplasmic antibody (ANCA) was positive in 73%; cytoplasmic ANCA 34%, peri-nuclear ANCA 26% and undifferentiated 14%. Twenty-seven per cent tested ANCA negative. The differences between the groups were small; time to diagnosis was shorter in the ANCA negative (-ve) group (P=0.02) and there were more airway symptoms in the ANCA positive (+ve) group (P:<0.05). All biopsies demonstrated a necrotizing process; crescents were seen in 96% involving (mean+/-SD) 54+/-26% of the glomeruli. Creatinine concentration (mean+/-SD) at diagnosis was 806+/-540 micromol/l. Treatment followed established immunosuppressive regimens. Initial dialysis was required by 59%, 36% needing long-term dialysis. At 1 year 68% were alive. The need for dialysis (P=0.0004) and age (P=0. 004) were poor prognostic markers. Ten per cent were transplanted, graft survival was 90% at 1 year, no recurrence was seen.

CONCLUSIONS

This study, looking at a large cohort, has established the incidence and outcome of ANCA +ve and ANCA -ve RPGN in a defined stable population. It stresses the similarities between ANCA +ve and ANCA -ve cases and supports the notion that pauci-immune RPGN is part of a continuum of vasculitic illness. In this series transplantation is a safe option.

Associations of fat distribution and obesity with hypertension in a bi-ethnic population: the ARIC study. Atherosclerosis Risk in Communities Study

OBJECTIVE

To examine associations of hypertension with obesity and fat distribution among African American and white men and women.

RESEARCH METHODS AND PROCEDURES

The analysis sample included 15,063 African American and white men and women between the ages of 45 and 64 years who were participants in the 1987 through 1989 examination of the Atherosclerosis Risk in Communities Study (ARIC). Odds ratios and adjusted prevalences of hypertension were calculated across sex-specific quintiles of body mass index (BMI), waist-to-hip ratio (WHR), waist circumference, and waist-to-height ratio (waist/ height) and adjusted for age, research center, smoking, education, physical activity, alcohol consumption, hormone replacement therapy, and menopausal status.

RESULTS

The prevalence of hypertension was higher among African Americans than whites. In the lowest quintile of BMI, 41% of African American women and 43% of African American men had hypertension compared with 14% of white women and 19% of white men. Elevated BMI, WHR, waist circumference, and waist/height were associated with increased odds of hypertension in African American and white men and women. In women, but not in men, there were significant interactions between ethnicity and the anthropometric variables studied here. The direction of the interaction indicated larger odds ratios for hypertension with increasing levels of anthropometric indices in white compared with African American women.

DISCUSSION

Obesity and abdominal fat preponderance were associated with increased prevalence of hypertension in African American and white men and women. Associations were similar among African American and white men, but obesity and fat patterning were less strongly associated with hypertension in African American than in white women.

Peptide specificity of RT1-A1(c), an inhibitory rat major histocompatibility complex class I natural killer cell ligand

The rat major histocompatibility complex class Ia allelomorph RT1-A1(c) is a potent ligand for the recently identified inhibitory rLy-49 receptor, STOK-2. With the ultimate objective of studying the interactions of these molecules using structural and functional methods, we undertook a detailed study of its peptide specificity. The study revealed that designing an "ideal peptide" by choosing the most abundant residues in the "binding motif" obtained by pool sequencing does not necessarily yield an optimal binding peptide. For RT1-A1(c), as many as four positions, P2, P4, P5, and P9, were detected as putative anchors. Since this molecule displays a preference for highly hydrophobic peptides, we tested binding of peptides derived from the known leader peptide sequences of other rat histocompatibility complex class I molecules. One such peptide, found to bind well, requiring 1.6 microm peptide to achieve 50% stabilization, was searched for in vivo. Natural RT1-A1(c) binding peptides were purified from rat splenocytes and characterized by mass spectrometry using a combined matrix-assisted laser desorption ionization/time-of-flight and quadrupole time-of-flight approach. Results showed that the signal sequence-derived peptide was not detectable in the purified peptide pool, which was composed of a complex spectrum of peptides. Seven of these self-peptides were successfully sequenced.

The trypanosomatid evolution workshop London School of Hygiene and Tropical Medicine. 17-18 February 2000

The trypanosome evolution workshop, a joint meeting of the University of Exeter and the London School of Hygiene and Tropical Medicine, focused on topics relating to trypanosomatid and vector evolution. The meeting, sponsored by The Wellcome Trust, The Special Programme for Research and Training in Tropical Disease of World Health Organization and the British Section of the Society of Protozoologists, brought together an international group of experts who presented papers on a wide range of topics including parasite and vector phylogenies, molecular methodology and relevant biogeographical data.

Blastocyst score affects implantation and pregnancy outcome: towards a single blastocyst transfer

OBJECTIVE

To determine the relationship between blastocyst score and pregnancy outcome.

DESIGN

Retrospective review of blastocyst transfer in an IVF clinic.

SETTING

Private assisted reproductive technology unit.

PATIENT(S)

107 patients undergoing blastocyst culture and transfer of two embryos.

INTERVENTION(S)

Culture of all pronucleate embryos in sequential media to the blastocyst stage (day 5), followed by transfer of two blastocysts.

MAIN OUTCOME MEASURE(S)

Implantation rates, pregnancy rates, and twinning were analyzed.

RESULT(S)

When a patient received two top-scoring blastocysts (64% of patients), implantation and pregnancy rates were 70% and 87%, respectively. The twinning rate in this group was 61%. When only one top-quality blastocyst was available for transfer (21% of patients), the implantation and pregnancy rates were 50% and 70%. The twinning rate for this group was 50%. In contrast, when only low-scoring blastocysts were available for transfer (15% of patients), implantation and pregnancy rates were 28% and 44%, and the twinning rate was 29%. No monozygotic twins were observed in this group of patients.

CONCLUSION(S)

The ability to transfer one high-scoring blastocyst should lead to pregnancy rates greater than 60%, without the complication of twins.

Impact of age on associations between weight and mortality

The effect of age on the weight associated with the lowest mortality and the effect of age on the mortality risk associated with obesity are issues fraught with methodologic complexities. Current evidence supports the notion that the body mass index associated with the lowest mortality falls within the range of 18.5 to 24.9 in men and women between the ages of 30 and 74. The impact of age on the mortality risk associated with obesity changes with age, however, and the direction of the trend depends upon the measure used.

Structure and sequence variation of the trypanosome spliced leader transcript

We have assessed the potential of using the spliced leader (SL) or mini-exon gene as a marker for molecular phylogenetic analysis of genus Trypanosoma. A total of 27 trypanosome sequences were compared, 18 of these being newly reported. In contrast to genus Leishmania, we found the non-transcribed spacer region of the SL locus in trypanosomes to be far too variable for informative comparison of all but the most closely related species. At the other extreme, the short (39 nt) SL exon was usually completely conserved and hence uninformative. The SL RNA showed variation in both length (97-152 nt) and sequence among different trypanosome species, with most variation occurring in stem-loop II. Consequently, this region could not be aligned with confidence in multiple sequence alignment, severely reducing the number of phylogenetically informative nucleotide positions. In computer simulation, most of the SL RNAs readily folded into the 3 stem-loop secondary structure predicted previously, but again stem-loop II was highly variable. No obvious correlation could be seen between the length of this stem-loop and trypanosome biology. We conclude that the SL repeat is not an informative phylogenetic marker for long range evolutionary studies of genus Trypanosoma.

Early detection of lead fracture by painless high voltage lead impedance measurement in a transvenous ICD lead system

We report the case of a 69 year old patient, who underwent transvenous implantable cardioverter defibrillator (ICD) device change (Medtronic GEM VR 7227 Cx Active Can) because the ICD reached its replacement indicators. Preoperative chest X-ray and intraoperative defibrillation threshold tests and high voltage impedance did not show lead fracture of the five year old lead (Transvene 6936-65). At the second postoperative day the alarm of the newly implanted ICD device was activated because of high impedance in the painless lead impedance measurement (PLI) and the lead was replaced. The explanted lead showed a fracture detectable only by PLI.

Pattern of premature degenerative changes of the cervical spine in patients with spasmodic torticollis and the impact on the outcome of selective peripheral denervation

OBJECTIVES

To characterise the pattern of and risk factors for degenerative changes of the cervical spine in patients with spasmodic torticollis and to assess whether these changes affect outcome after selective peripheral denervation.

METHODS

Preoperative CT of the upper cervical spine of 34 patients with spasmodic torticollis referred for surgery were reviewed by two radiologists blinded to the clinical findings. Degenerative changes were assessed for each joint separately and rated as absent, minimal, moderate, or severe. Patients were clinically assessed before surgery and 3 months postoperatively by an independent examiner using standardised clinical rating scales. For comparison of means a t test was carried out. To determine whether an association exists between the side of degenerative changes and type of spasmodic torticollis a chi(2) test was used. Changes in severity, disability, and pain before and after surgery were calculated using a Wilcoxon matched pairs signed ranks test.

RESULTS

Fourteen out of 34 patients had moderate or severe degenerative changes. They were predominantly found at the C2/C3 and C3/C4 level and were significantly more likely to occur on the side of the main direction of the spasmodic torticollis (p = 0.015). There was no significant difference in age, sex, duration of torticollis, overall severity, degree of disability, or pain between the group with either no or minimal changes and the group with moderate or severe changes. However, in the second group the duration of inadequate treatment was longer (10.1 v 4.8 years; p=0.009), head mobility was more restricted (p = 0.015), and head tremor was more severe (p = 0.01). At 3 months postoperatively, patients with n or minimal degenerative changes showed a significant improvement in pain and severity whereas no difference was found in those with moderate or severe changes.

CONCLUSIONS

Patients with spasmodic torticollis have an increased risk of developing premature degenerative changes of the upper cervical spine that tend to be on the side towards which the head is turned or tilted and compromise outcome after surgery. Effective early treatment of spasmodic torticollis with botulinum toxin seems to have a protective effect. Patients with spasmodic torticollis and restricted head mobility who do not adequately respond to treatment should undergo imaging of the upper cervical spine. Patients with imaging evidence of moderate or severe degenerative changes seem to respond poorly to selective peripheral denervation.

Imaging and radiological-pathological correlation in histologically proven cases of focal cortical dysplasia and other glial and neuronoglial malformative lesions in adults

Focal cortical dysplasia (FCD) is a pathological entity first described in 1971. Other more subtle cortical malformations found in patients with epilepsy include microdysgenesis (MD), and glioneuronal hamartias. Although these glial and neuronoglial malformations have distinct histological features, there is terminological confusion in the radiological literature. Few cases have been reported in adults with both imaging and histology. We address these issues, giving a radiological-pathological correlation of histologically proven cortical malformations in adults. We describe clinical, radiological and histological features of 12 cases (five FCD, five MD with glioneuronal hamartias, and two hamartomas), unassociated with other conditions, and discuss them in the light of the literature. FCD is usually seen on MRI as cortical thickening, with or without signal change, which may extend into the adjacent white matter. On histology, abnormal neurons and/or glial cells, blurring of the grey-white matter interface, myelin pallor, demyelination, and gliosis may be found. Glioneuronal hamartias and hamartomas usually appear as complex masses on MRI. FCD and hamartias may be associated, and a combination of imaging findings may be seen on MRI. Atrophy of the ipsilateral hippocampus may be present on MRI in patients with hamartias, and minor cell loss on histology, but not definitive hippocampal sclerosis. Although the imaging findings of cortical malformations are protean, some characteristic MRI features, with histological correlates, may be found. The relevance of most of these observations remains unclear.

Analysis of peptide length preference of the rat MHC class Ia molecule RT1-A(u), by a modified random peptide library approach

Using random peptide libraries we have previously shown that both mouse and rat class I molecules can exhibit different peptide length preferences. Such studies required expression of the particular class I molecules in RMA-S, a cell line deficient in the transporter associated with antigen presentation (TAP). For another rat class I molecule called RT1-A(u), however, we found that expression in RMA-S was poor and could not be increased sufficiently by incubation at 26 degrees C. To circumvent this problem we performed our studies on C58, a rat cell line that expresses RT1-A(u) naturally in the presence of a functional TAP transporter. Using C58 cells, cell-surface-expressed class I molecules were 'stripped' of peptides and beta(2)-microglobulin by washing the cells with an acidic citrate buffer (pH 3.3). Peptide stabilization assays, assessed by FACS analysis, were then performed using either specific peptides or synthetic random peptide libraries of different lengths (7-15 amino acids), supplemented with recombinant rat beta(2)-microglobulin. As a positive control an RT1-A(u)-specific nonamer peptide was designed using the previously determined peptide binding motif and this was found to bind to RT1-A(u) at nanomolar concentrations. Both length preference and importance of free N- and C-termini were tested using free base, formylated and acetylated peptide libraries. Results showed that RT1-A(u) was not able to accommodate N- or C-terminally blocked peptides but displayed a preference for peptides of 9-12 amino acids, similar to the preference observed for the RT1-A1(c) allotype, the other rat TAP-B-associated molecule tested thus far. These results suggest that length preference remains a consideration to explain the allelic class I-TAP associations of the RT1-A region.

Emergency cranial computed tomography in the management of acute febrile encephalopathy in children

OBJECTIVE

Evaluation of the influence of emergency cranial computed tomography on the management of acute febrile encephalopathy in children.

METHODS

A retrospective study in children with acute febrile encephalopathy who underwent emergency cranial computed tomography within 12 hours of admission to the paediatric intensive care unit. All scans were evaluated by two independent radiologists.

RESULTS

Thirty nine children were included. Fourteen scans were abnormal and two had clinically insignificant incidental findings. Four children with focal neurological signs had scans demonstrating extra-axial collections. None required neurosurgical intervention. Clinically, raised intracranial pressure was present in 10 patients. Only five had cerebral oedema on computed tomography; these five children died. Emergency cranial computed tomography influenced subsequent management in no child without focal neurological signs and in only one child with focal neurology.

CONCLUSION

Emergency cranial computed tomography in acute febrile encephalopathy in children without focal neurological signs has little influence on subsequent management. Where cranial computed tomography is thought to be necessary, it should be carried out when the child's clinical condition has been stabilised.