Diagnosis of Multisystem Inflammatory Syndrome in Children by a Whole-Blood Transcriptional Signature

BACKGROUND

To identify a diagnostic blood transcriptomic signature that distinguishes multisystem inflammatory syndrome in children (MIS-C) from Kawasaki disease (KD), bacterial infections, and viral infections.

METHODS

Children presenting with MIS-C to participating hospitals in the United Kingdom and the European Union between April 2020 and April 2021 were prospectively recruited. Whole-blood RNA Sequencing was performed, contrasting the transcriptomes of children with MIS-C (n = 38) to those from children with KD (n = 136), definite bacterial (DB; n = 188) and viral infections (DV; n = 138). Genes significantly differentially expressed (SDE) between MIS-C and comparator groups were identified. Feature selection was used to identify genes that optimally distinguish MIS-C from other diseases, which were subsequently translated into RT-qPCR assays and evaluated in an independent validation set comprising MIS-C (n = 37), KD (n = 19), DB (n = 56), DV (n = 43), and COVID-19 (n = 39).

RESULTS

In the discovery set, 5696 genes were SDE between MIS-C and combined comparator disease groups. Five genes were identified as potential MIS-C diagnostic biomarkers (HSPBAP1, VPS37C, TGFB1, MX2, and TRBV11-2), achieving an AUC of 96.8% (95% CI: 94.6%-98.9%) in the discovery set, and were translated into RT-qPCR assays. The RT-qPCR 5-gene signature achieved an AUC of 93.2% (95% CI: 88.3%-97.7%) in the independent validation set when distinguishing MIS-C from KD, DB, and DV.

CONCLUSIONS

MIS-C can be distinguished from KD, DB, and DV groups using a 5-gene blood RNA expression signature. The small number of genes in the signature and good performance in both discovery and validation sets should enable the development of a diagnostic test for MIS-C.

High-intensity interval training in cardiac rehabilitation (HIIT or MISS UK): A multi-centre randomised controlled trial

BACKGROUND

There is a lack of international consensus regarding the prescription of high-intensity interval exercise training (HIIT) for people with coronary artery disease (CAD) attending cardiac rehabilitation (CR).

AIM

To assess the clinical effectiveness and safety of low-volume HIIT compared with moderate intensity steady-state (MISS) exercise training for people with CAD.

METHODS

We conducted a multi-centre RCT, recruiting 382 patients from 6 outpatient CR centres. Participants were randomised to twice-weekly HIIT (n = 187) or MISS (n = 195) for 8 weeks. HIIT consisted of 10 × 1-minute intervals of vigorous exercise (>85% maximum capacity) interspersed with 1-minute periods of recovery. MISS was 20-40 minutes of moderate intensity continuous exercise (60-80% maximum capacity). The primary outcome was the change in cardiorespiratory fitness (peak oxygen uptake, VO2 peak) at 8-week follow-up. Secondary outcomes included cardiovascular disease risk markers, cardiac structure and function, adverse events, and health-related quality of life.

RESULTS

At 8 weeks, VO2  peak improved more with HIIT (2.37 mL.kg-1.min-1; SD, 3.11) compared with MISS (1.32 mL.kg-1.min-1; SD, 2.66). After adjusting for age, sex and study site, the difference between arms was 1.04 mL.kg-1.min-1 (95% CI, 0.38 to 1.69; p = 0.002). Only 1 serious adverse event was possibly related to HIIT.

CONCLUSIONS

In stable CAD, low-volume HIIT improved cardiorespiratory fitness more than MISS by a clinically meaningful margin. Low-volume HIIT is a safe, well tolerated, and clinically effective intervention that produces short-term improvement in cardiorespiratory fitness. It should be considered by all CR programmes as an adjunct or alternative to MISS.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02784873. https://clinicaltrials.gov/ct2/show/NCT02784873.

2351. Systemic Influenza Infection Impairs Whole Blood Control of Mycobacteria in a Human Challenge Study

Background

Of the millions of people infected with Mycobacterium tuberculosis (Mtb) each year, only a small proportion will develop TB disease, with most immunologically containing or clearing Mtb. Factors influencing TB progression risk are incompletely understood. Co-infections, including influenza, have been proposed as a risk factor for TB progression via disruption of anti-Mtb immune responses. We employed a human influenza challenge study to investigate the effect of systemic influenza infection on host mycobacterial control.

Methods

A whole blood (WB) mycobacterial growth inhibition assay was utilised to compare mycobacterial growth and anti-mycobacterial immune responses before and after influenza infection. Thirty adults were per-nasally inoculated with H3N2 influenza virus (Day [D] 0). Influenza PCR assay of D4 nasal swab confirmed infection. WB, collected pre- (D0, “pre-influenza”) and post-inoculation (D6, “post-influenza”), was infected with Mycobacterium bovis Bacille Calmette Guerin (BCG)-lux, incubated for 72 hours (h) and WB mycobacterial growth (growth ratio [GR]) measured. In parallel, BCG-lux-infected and uninfected blood aliquots were incubated for 0, 6, 24 and 72 h and measurements of cytokines (Meso Scale) and gene expression (RNA-Sequencing) undertaken. Comparisons between pre- and post-influenza infection blood samples were made (Fig. 1).

Blood was aliquoted into triplicate for each timepoint (0 hours [h], 72 h), diluted 1:1 with Gibco Roswell Park Memorial Institute 1640 Medium (RPMI), inoculated with a fixed quantity of BCG-lux and incubated at 37°C in a rocker-incubator. Previous experiments had confirmed and quantified the correlation between BCG-lux luminescence (measured in Relative Light Units [RLU] by a luminometer) and number of mycobacterial colony forming units. At 0 h and 72 h, the luminescence of each triplicate sample was measured in duplicate. The growth ratio (GR) was calculated by division of the median 72 h luminescence value by the median 0 h luminescence value. In parallel, BCG-lux inoculum or sterile PBS were added to additional whole blood aliquots (to give infected and uninfected aliquots), which were incubated at 37°C in a rocker-incubator. At timepoints 0 h, 6 h, 24 h, and 72 h, aliquots were removed from the incubator and centrifuged. Supernatants were frozen and stored for future cytokine analyses (quantification using Meso Scale Discovery [MSD] U-plex). Cell pellets were stabilised and stored for future RNA-sequencing and transcriptomic analysis. Figure created with BioRender.com.

Results

In 22 influenza PCR-positive (+) subjects, median GR was significantly higher in post- (1.69) vs pre-influenza samples (1.03, p=0.0016) with no significant difference in the PCR-negative subjects (Fig. 2). Significant differences in BCG-lux-stimulated cytokine production were observed between post- and pre-influenza samples in PCR+ subjects (Fig. 3). Transcriptomic analysis identified significantly differentially expressed genes in the post- vs pre-influenza samples and differences between the groups over time, mapping to pathways related to TB susceptibility.

Complete BCG-lux growth ratio (GR) data were available for 28/30 participants. Comparisons of median GRs pre- and post-influenza infection for (A) 22 participants who were influenza PCR-positive on day 4 and (B) 6 participants who were influenza PCR-negative on day 4. Significance (paired analysis): ** p≤0.01; ns p>0.05. (C) Change in GR from pre-influenza baseline was calculated for each individual (GR-Post divided by GR-Pre, expressed as a percentage) and compared between the influenza PCR-positive and PCR-negative participants. Significance: ** p≤0.01.

Cytokine concentrations were measured in duplicate in supernatants from blood incubated with BCG-lux for 0 hours (h), 6 h, 24 h and 72 h, using Meso Scale Discovery U-plex. Results are available for a subset of 15 participants who had influenza infection confirmed by influenza PCR-positive assay on day 4 nasal swab. Comparisons of median concentrations between pre- and post-influenza samples and individual participants’ paired samples are shown for (A, B) Interleukin-1β (IL-1β) at 24 h; (C, D) Tumour necrosis factor-α (TNF-α) at 6 h; (E, F) Interleukin-10 (IL-10) at 0 h; (G, H) IL-10 at 24 h. Significance (paired analysis): **** p≤0.0001; ** p≤0.01.

Conclusion

Systemic influenza infection reduces whole blood control of mycobacteria through modulation of anti-mycobacterial immune responses. Cytokine differences may contribute. These novel findings suggest that influenza may be a risk factor for TB disease and influenza vaccine could have a non-specific effect on TB immunity.

Disclosures

Christopher W. Woods, MD MPH, Predigen, Inc: Co-founder Christopher Chiu, BMBCh PhD, GlaxoSmithKline: Grant/Research Support|Merck: Grant/Research Support|Reithera: Advisor/Consultant.

Characterisation of the blood RNA host response underpinning severity in COVID-19 patients

Infection with SARS-CoV-2 has highly variable clinical manifestations, ranging from asymptomatic infection through to life-threatening disease. Host whole blood transcriptomics can offer unique insights into the biological processes underpinning infection and disease, as well as severity. We performed whole blood RNA Sequencing of individuals with varying degrees of COVID-19 severity. We used differential expression analysis and pathway enrichment analysis to explore how the blood transcriptome differs between individuals with mild, moderate, and severe COVID-19, performing pairwise comparisons between groups. Increasing COVID-19 severity was characterised by an abundance of inflammatory immune response genes and pathways, including many related to neutrophils and macrophages, in addition to an upregulation of immunoglobulin genes. In this study, for the first time, we show how immunomodulatory treatments commonly administered to COVID-19 patients greatly alter the transcriptome. Our insights into COVID-19 severity reveal the role of immune dysregulation in the progression to severe disease and highlight the need for further research exploring the interplay between SARS-CoV-2 and the inflammatory immune response.

Estimated peak functional capacity: an accurate method for assessing change in peak oxygen consumption after cardiac rehabilitation?

OBJECTIVE

Cardiopulmonary exercise testing (CPET) is the 'gold standard' method of determining VO_2peak . When CPET is unavailable, VO_2peak may be estimated from treadmill or cycle ergometer workloads and expressed as estimated metabolic equivalents (METs). Cardiac rehabilitation (CR) programmes use estimated VO_2peak (METs) to report changes in cardiorespiratory fitness (CRF). However, the accuracy of determining changes in VO_2peak based on estimated functional capacity is not known.

METHODS

A total of 27 patients with coronary heart disease (88·9% male; age 59·5 ± 10·0 years, body mass index 29·6 ± 3·8 kg m^-2 ) performed maximal CPET before and after an exercise-based CR intervention. VO_2peak was directly determined using ventilatory gas exchange data and was also estimated using the American College of Sports Medicine (ACSM) leg cycling equation. Agreement between changes in directly determined VO_2peak and estimated VO_2peak was evaluated using Bland-Altman limits of agreement (LoA) and intraclass correlation coefficients.

RESULTS

Directly determined VO_2peak did not increase following CR (0·5 ml kg^-1 min^-1 (2·7%); P = 0·332). Estimated VO_2peak increased significantly (0·4 METs; 1·4 ml kg^-1  min^-1 ; 6·7%; P = 0·006). The mean bias for estimated VO_2peak versus directly determined VO_2peak was 0·7 ml kg^-1  min^-1 (LoA -4·7 to 5·9 ml  kg^-1  min^-1 ). Aerobic efficiency (ΔVO₂ /ΔWR slope) was significantly associated with estimated VO_2peak measurement error.

CONCLUSION

Change in estimated VO_2peak derived from the ACSM leg cycling equation is not an accurate surrogate for directly determined changes in VO_2peak . Our findings show poor agreement between estimates of VO_2peak and directly determined VO_2peak . Applying estimates of VO_2peak to determine CRF change may over-estimate the efficacy of CR and lead to a different interpretation of study findings.

Cerebrospinal Fluid Analysis in Recumbent Adult Dairy Cows With or Without Spinal Cord Lesions

Background

Diagnosis of central nervous system (CNS) lesions in recumbent dairy cattle (RDC) is challenging because neurologic examination is limited and medical imaging often is challenging or unrewarding. Cerebrospinal fluid (CSF) analysis is useful in the diagnosis of CNS disorders in cattle. However, its utility in identifying spinal cord lesions in RDC remains to be evaluated.

Hypothesis/Objectives

We hypothesized that CSF analysis would discriminate between RDC with and without spinal cord lesions.

Animals

Twenty‐one RDC with spinal cord lesions (RDC+) and 19 without (RDC−) were evaluated.

Methods

Spinal cord lesions were confirmed at necropsy. Signalment, clinical findings, and CSF results were compared retrospectively. Total nucleated cell count and differential, protein concentration, and red blood cell count in RDC+ and RDC− were compared.

Results

Neoplasia, trauma, and infectious processes were the most frequent spinal cord lesions identified. Cerebrospinal fluid protein concentrations and TNCC were significantly higher in RDC+ compared to RDC− (P = .0092 and P = .0103, respectively). Additionally, CSF protein concentrations and TNCC in RDC− were lower than previously published reference ranges. Using an interpretation rule based on CSF protein concentration and TNCC, it was possible to accurately identify 13 RDC with spinal cord lesions and 6 RDC without lesions. It was not possible to determine spinal cord status in the remaining 18 RDC.

Conclusions and Clinical Importance

Cerebrospinal fluid analysis is valuable in the evaluation of spinal cord status in RDC. The prognosis associated with these findings remains to be determined.

Variability of automated carotid intima-media thickness measurements by novice operators

Carotid intima-media thickness (C-IMT) measurements provide a non-invasive assessment of subclinical atherosclerosis. The aim of the study was to assess the inter- and intra-observer variability of automated C-IMT measurements undertaken by two novice operators using the Panasonic CardioHealth Station. Participants were free from cardio-metabolic disease, and each underwent serial bilateral C-IMT ultrasound measurements. Immediate interoperator measurement variability was calculated by comparing initial measurements taken by two operators. Immediate retest variability was calculated from two consecutive measurements and longer term variability was assessed by conducting a further scan 1 week later. Fifty apparently healthy participants (n = 20 females), aged 26·2 ± 5·0 years, were recruited. Operator 1 recorded a median (interquartile range) right and left-sided C-IMT of 0·471 mm (0·072 mm) and 0·462 mm (0·047 mm). Female's right and left C-IMT were 0·442 mm (0·049 mm) and 0·451 mm (0·063 mm), respectively. The limits of agreement (LoA) for immediate interoperator variability were -0·063 to 0·056 mm (mean bias -0·003 mm). Operator 1's immediate retest intra-operator LoA were -0·057 to 0·046 mm (mean bias was -0·005 mm). One-week LoA were -0·057 to 0·050 mm (mean bias -0·003 mm). Operator 2 recorded median right and left-sided C-IMT of 0·467 mm (0·089 mm) and 0·458 mm (0·046 mm) for males, respectively, whilst female measurements were 0·441 mm (0·052 mm) and 0·444 mm (0·054 mm), respectively. Operator 2's intra-operator immediate retest LoA were -0·056 to 0·056 (mean bias <-0·001 mm). Intra-operator LoA at 1 week were -0·052 to 0·068 mm (mean bias 0·008 mm). Novice operators produce acceptable short-term and 1-week inter- and intra-operator C-IMT measurement variability in healthy, young to middle-aged adults using the Panasonic CardioHealth Station.

Validation of an ultrasound imaging technique of the tympanic bullae for the diagnosis of otitis media in calves

Background

Otitis media is a common disease in calves that can be subclinical, making antemortem on‐farm diagnosis challenging.

Objectives

To evaluate the sensitivity and specificity of ultrasonography of tympanic bullae for the diagnosis of clinical and subclinical otitis media and to evaluate the reproducibility of the technique.

Animals

Forty calves 19–50 days of age were selected from a veal calf farm.

Methods

Prospective study. Ultrasonography was first performed on the farm by ultrasonographer A (US A). Ultrasonography was repeated by ultrasonographer A (US A') and another ultrasonographer (US B) at the Centre Hospitalier Universitaire Vétérinaire. Images were later reread by both examiners and a diagnosis was recorded. The calves were euthanized and submitted for necropsy, and histopathologic diagnosis was used as the gold standard.

Results

Forty‐five bullae were affected by otitis media and 35 bullae were normal. Sensitivity and specificity of the ultrasound technique ranged from 32 to 63% and 84 to 100%, respectively, depending on the examiner and classification of suspicious ultrasonography results. Kappa analysis to evaluate interobserver agreement between A' and B yielded a к value of 0.53. Agreement within the same examiner (A versus A') yielded a к value of 0.48, and real‐time ultrasound versus rereading of recorded images for A' and B yielded к values of 0.58 and 0.75, respectively.

Conclusions

Sensitivity and specificity of the ultrasound imaging technique are, respectively, low and high for diagnosis of clinical and subclinical otitis media in calves, with moderate reproducibility.

Anthropometry and blood pressure changes in a Caribbean adolescent population of African ancestry: an evaluation of longitudinal data using a multilevel mixed regression approach

OBJECTIVE

The aim of this study was to determine the effect of growth pattern on blood pressure changes in an adolescent population of African ancestry based on longitudinal data and to compare this with estimates derived from cross-sectional data.

METHODS

Participants had measurements of weight, height, blood pressure and percentage body fat taken annually using standardized procedures. Annual blood pressure and anthropometry velocities as well as one- and three-year interval gender specific tracking coefficients were computed. We investigated whether changes in blood pressure could be explained by measures of growth using a multilevel mixed regression approach.

RESULTS

The results showed that systolic blood pressure (SBP) increased by 1.27 and 3.09 mmHg per year among females and males, respectively. Similarly, diastolic blood pressure (DBP) increased by 1.16 and 1.92 mmHg per year among females and males, respectively. Multilevel analyses suggested that weight, body mass index, percentage body fat and height were the strongest anthropometric determinants of blood pressure change in this population. The results also suggest that there are gender differences in the relative importance of these anthropometric measures with height playing a minor role in predicting blood pressure changes among adolescent females. With the exception of DBP at 18 years among females, there were no significant differences between mean blood pressure generated from cross-sectional and longitudinal data by age in both males and females.

CONCLUSION

Anthropometric measures are important covariates of age-related blood pressure changes and cross-sectional data may provide a more cost-effective and useful proxy for generating age-related blood pressure estimates in this population.

[Sputum smear conversion during intensive TB treatment phase according to HIV status, in hospitalised patients in Togo]

METHOD

We prospectively studied patients with pulmonary TB, with or without HIV-1 co-infection, from December 1, 2007 to December 1, 2008. Two groups of patients naive for TB and antiretroviral treatment (group A: 96 co-infected TB/HIV and group B: 171 TB infected but HIV negative) were selected randomly. The CD4 count was assessed according to HIV status, and all patients received RHEZ TB treatment for 2 months. Pulmonary smear was assessed at two weeks, four weeks, six weeks, and eight weeks.

RESULT

Two hundred and sixty seven patients were treated (26.6% of admissions). The mean age was 34.62 ± 11 years and the sex ratio was 1.3. A proportion of 35.75% patients were HIV co-infected with a median CD4 count at 157 cells per millimeter cube. The sputum smear conversion was obtained for more than 87.5% of patients in group A and 24.56% in group B at two weeks; 94% of patients in group A and 61.83% in group B at four weeks; 100% of patients in group A and 87.33% in group B at six weeks, and 100% of patients in group A and 96.77% in group B at eight weeks. P<0.05 at six weeks.

CONCLUSION

HIV infected TB patients were more susceptible to treatment than TB/HIV infected patients in the first six weeks.

The nutritional status of clinic attendees living with HIV/AIDS in St Vincent and the Grenadines

OBJECTIVES

The purpose of this study was to assess nutritional status and dietary practices in persons living with HIV/AIDS (PLWHA).

METHODS

A case-control design was used. Cases consisted of 36 PLWHA. Controls consisted of 37 persons within the same age range from the general population. Participants filled out a questionnaire consisting of sociodemographic, dietary and health history items. In addition, they had weight, height, upper mid-arm circumference and triceps skinfold measured using standard procedure. Biochemical and clinical data for cases were extracted from their clinic file.

RESULTS

HIV-positive persons had significantly lower mean weight, BMI, upper mid-arm circumferences, arm muscle area and arm fat area than persons in the control group. They were also less likely to use multivitamins, dietary supplements, fruit and vegetables than persons in the control group. Correlation coefficients between corrected arm muscle area (CAMA) and BMI and weight ranged from 0.67 to 0.74 in cases and 0.41 to 0.68 for the control group, respectively. Screening for depleted CD4 counts using gender specific CAMA cut-offs indicative of depleted arm muscle reserves resulted in 48% sensitivity and 100% specificity in identifying PLWHA with CD4 counts < 200 cells/microL.

CONCLUSION

The findings suggest that PLWHA are at increased risk for poor intakes of fruits and vegetables and depleted lean body mass. In addition, CAMA along with other clinic measures might be useful in the identification of PLWHA who might be responding adequately to treatment.

Blood pressure and its correlates in Tobagonian adolescents

OBJECTIVE

To determine age-specific patterns and correlates of blood pressure (BP) in Tobagonian adolescents.

METHODS

Blood pressure, weight and heights were measured using standardized procedures. Age-height and gender-specific BP levels were established and compared with those established for adolescents in the United States of America, the United Kingdom and Jamaica.

RESULTS

Of the available population, 3749 or 84.9% participated in the study. Among Tobagonian adolescents, the mean one-year age increment in systolic blood pressure (SBP) was 3.6 (95% CI: 3.2, 3.9) mmHg in males and 1.5 (95% CI: 1.2, 1.8) mmHg in females. Likewise, the mean one-year increment in diastolic blood pressure (DBP) was 2.1 (95% CI: 1.7, 2.4) mmHg in males and 1.2 (95% CI: 0.9, 1.4) mmHg in females. There was an inversion of mean BP with age. Females 12-13 years having significantly higher mean SBP while those 15-18 years had lower SBP than their male counterparts. Similarly, females 12-14 years had significantly higher mean DBP while those 16-18 years had lower DBP than their male counterparts. Approximately, 6.1% (95% CI: 5.4, 7.0) and 8.2% (95% CI: 7.4, 9.1) of participants had elevated SBP and DBP based on the US reference standards. Adolescents from the UK had average SBP and DBP that were 10 mmHg higher and lower respectively than their Tobagonian counterparts while Jamaican adolescents had diastolic BP consistently lower than Tobagonian adolescents of similar age. Elevated BP was associated with overweight and family history of hypertension.

CONCLUSION

Growth and maturational factors are important determinants of blood pressure levels in this population. Furthermore, the wide variation in these key variables among possible BP referent populations necessitates the development of local blood pressure reference standards for Tobagonian adolescent populations.

Patient satisfaction and quality of life among persons attending chronic disease clinics in South Trinidad, West Indies

OBJECTIVE

Patient satisfaction and quality of life are increasingly being recognized as central elements in the monitoring and evaluation of healthcare. In this survey, the level of patient satisfaction and quality of life were investigated in regular attendees at public health chronic disease facilities in South Trinidad.

METHOD

A random sample of 200 clients attending the three public chronic disease clinics during the period August 12, 2002 to December 31, 2002, completed self-administered questionnaires consisting of socio-demographic, quality of life (SF 12) and health service items.

RESULTS

Participants had an average of four annual visits and 75% of them were 50 years and older. Approximately two-thirds of participants gave health and support staff a rating of good to excellent. Overall clinic experience was rated as poor to fair by 41.5%. Forty-five and a half per cent gave a rating of the explanations given by doctors and nurses about their illnesses. Fifty-three and a half per cent and 58% gave a poor to fair rating for the length of the waiting time and explanation offered when there was a significant delay in the starting times of clinics respectively. In regression analyses controlling for age, gender and number of illnesses, ratings of clinic experience and all categories of clinic staff were significantly associated with SF-12 mental and physical component summary scores.

CONCLUSION

The findings suggest that in this population of regular clinic attendees, levels of client satisfaction and numbers of illnesses are associated with subjective quality of life.

Weight, fat mass, and central distribution of fat increase when women use depot-medroxyprogesterone acetate for contraception

OBJECTIVE

To compare longitudinal changes in weight, body fat, and ratio of central to peripheral fat mass among first-time depot-medroxyprogesterone acetate (DMPA) users to women using no hormonal contraception, and to evaluate user characteristics associated with that change.

DESIGN

Prospective longitudinal study.

SUBJECTS

Healthy women, aged 18-35 y, using DMPA for contraception (n=178) and women using no hormonal contraception (n=145).

MEASUREMENTS

Weight, body fat, and the central distribution of fat, measured at 3-month intervals for 30 months, by electronic scale and dual-energy X-ray absorptiometry (DEXA). The ratio of central to peripheral distribution of body fat was computed by dividing the body fat in the conventional DEXA trunk region of interest (ROI) by the ROI's that encompass the arms, hips and legs.

RESULTS

Women using DMPA had a significantly greater increase in all measures of fatness than women using no hormonal method of contraception (P<0.03). The observed weight of DMPA users increased from a mean of 69.4 kg (s.d.=16.9) at baseline to 75.5 kg (s.d.=25.0) at 30 months; an increase of 6.1 kg (8.8.%). Fat mass increased from a mean of 25.3 kg (s.d.=12.6 kg) at baseline to 31.4 kg (s.d.=17.8); an increase of 6.1 kg (23.6%) in DMPA users. The ratio of central to peripheral fat mass in DMPA users changed from 0.95 (s.d.=0.155) at baseline to 1.01(s.d.=0.198) at 30 months. In contrast, weight, fat mass and the ratio of central to peripheral fat mass of control participants remained virtually unchanged over the same time period. Women with higher baseline physical activity levels had a smaller increase in body fat (P=0.003) and the fat ratio (P=0.03), but not weight (P=0.48). No other user characteristics including, smoking, past oral contraceptive use or previous pregnancies predicted change in level of fatness.

CONCLUSIONS

This study has demonstrated a change in body composition toward greater fatness and toward a central redistribution of fat among DMPA users as compared to controls and provides important information to be used when counseling women regarding contraceptive methods. Given the potential long-term implication of these changes, further study is recommended to determine whether the gains in fatness are reversed following DMPA discontinuation and to examine the role of progestins in the development and maintenance of obesity.

The quality of health research reporting by the daily newspapers in Trinidad and Tobago

In this study, the authors examined the scientific quality of health research reported in the three daily newspapers in Trinidad and Tobago. All medical research articles published for the period January 1 to December 31, 2003, were extracted using a standardized data collection form. The scientific quality of the articles was analyzed by taking into consideration various aspects of study design, as well as other issues associated with accurate reporting. Of the 321 eligible articles, 108 were collected from The Trinidad Express, 100 from The Trinidad Guardian and 113 from The Trinidad and Tobago Newsday. The percentages of articles reporting methodological components consistent with good scientific quality were as follows: objective(s) (99.7%), study design (79.8%), study procedure (70.1%), selection procedure (70.1%), description of participants (87.5%), control/matching group (74.9%), outcome variables (99.4%) and issues of validity and reliability (2.5%). In addition, the percentage of articles containing aspects of good report writing were as follows: authorship (71.3%), authors' affiliation (59.5%), location of the study (25.4%), source of the research material (83.1%), duration of the study (27.7%), study setting (72.0%), number of participants (74.1%), period in which the study was conducted (12.0%) and quantification of the results (66.7%). Observational studies were significantly more likely to be reported than experimental studies (71.5% versus 28.5%). Overall, articles reported in the Trinidad Express and the Trinidad and Tobago Newsday were of a better scientific quality than those in the Trinidad Guardian. These findings suggest a need to improve the overall scientific quality of reported health research in these newspapers by ensuring that reports answer the fundamental questions of what, why, who, where, when and how. This might be achieved by adopting a structured reporting format similar to that used by many peer-reviewed journals.

A content analysis of health research reported by the daily newspapers of Trinidad and Tobago

The ability to translate health research into useful information for the layperson requires both excellent scientific expertise and communication skills that are often foreign to journalist and editors. In this study, we assessed the content of health research articles published in the local daily newspapers for the year 2003. Issues considered included physical presentation, coverage, primary content of the article relative to the country health profile, accuracy of the article compared to its original publication, health model (ie preventative versus medical/curative) and tone (emotive nature of the report, stakeholder addressed). The authors identified 321 eligible articles as follows, The Trinidad Express (108), The Trinidad Guardian (100) and The Trinidad and Tobago Newsday (113). More than 90% of the reports appeared in the newspapers within two weeks of their original journal publication; 10.5% of the articles had over 50% newspaper readership coverage. Headlines were prominently displayed for 70% of articles while 86% of the written text were located on the top right and left quadrant of pages where the eye naturally falls during reading. Photographs accompanied 36% of the articles. Approximately 72.5% of articles accurately reflected the content of the original publication and 67% of them were classified as preventative. There were similar proportions of good (45%) and bad (47%) articles. The top five predominant themes were nutrition (24.3%), cancer (18.2%) women's health (17.6%), heart disease (14.2%) and mental health (10.3%). The findings suggest a tremendous effort by journalist and editors to provide relevant health information in a timely and attractive manner; however, this should not be at the expense of accuracy.

Ethnicity, body image perception and weight-related behaviour among adolescent females attending secondary school in Trinidad

OBJECTIVE

The correlates of body image perception among an ethnically diverse group of adolescent females attending secondary school in Trinidad were investigated.

METHODS

A cross-sectional survey was carried out among adolescent females from selected secondary schools in Trinidad. Participants completed a self-administered questionnaire consisting of sociodemographic items and standardized psychometric instruments.

RESULTS

Two hundred and fifty-one students participated in the survey with an ethnic composition as follows: Indo-Trinidadian (35.9%), Afro-Trinidadian (28.7%), Indo-Afro mixed Trinidadian (21.9%) and other (13.5%). The results suggest that 2.4% of the participants reported having a medical diagnosis for an eating disorder Indo-Trinidadians had significantly greater body dissatisfaction than Indo-Afro-mixed Trinidadians but not more than Afro-Trinidadians (p = 0.04). Also, a significantly higher proportion of Indo-Trinidadians engaged in binge eating behaviour compared to the other ethnic groups (p < 0.001). Afro-Trinidadians were more likely to use vomiting as a mean of weight control compared to Indo- and Indo-Afro-mixed Trinidadian (p < 0. 05). Fifty-one per cent of participants had a negative body image perception. Altered body image perception was associated with a significant higher mean Body Shape Questionnaire BSQ 16 score (p < 0.001) and increased likelihood of reporting being diagnosed with an eating disorder (OR = 2.03, 95% CI: 1.78, 2.31; p = 0.01) compared to non-altered body image state. Eating Attitude Test (EAT-26) score was positively correlated with Drive-for-Thinness (p < 0.001) and BSQ16 (p < 0.001) scores and inversely correlated with the Rosenberg self-esteem score (p = 0.012).

CONCLUSION

In this group of adolescents, there are ethnic differences in the level of concern over body image and associated eating, and weight-related behaviour.

107 COMPARISON OF PRIMATE SPERM CRYOPRESERVATION PROTOCOLS: POST-THAW SPERM RECOVERY AND HYPERACTIVATION IN CULTURE

Cryopreservation of spermatozoa provides material for gene banking of genetically valuable males and offers convenience for in vitro fertilization (IVF). In addition, cryobanking of spermatozoa allows less frequent ejaculation collections from males. The present study compared the effectiveness of several published techniques in non-human primates to find the most efficient one for rhesus macaque (Macaca mulatta) semen cryopreservation. The effectiveness of each method was assessed by longevity (post-thaw motility % and duration) and ability to hyperactivate in culture in response to chemical activators (caffeine, dbcAMP) needed for rhesus sperm capacitation (Boatman and Bavister 1984 J. Reprod. Fertil. 71, 357-366). The ability to hyperactivate provides a reasonable assessment of the fertilizing capability of spermatozoa prior to performing IVF; the latter was impractical for this study, given the large number of treatments and endpoints. Spermatozoa were collected via electroejaculation from one male on three occasions to avoid confounding treatments with male effects. Each ejaculate was divided into one of four treatment groups for cryopreservation: Method A (Seier et al. 1993 J. Med. Primatol. 22, 355-359); Method B (Wei et al. 2000); Method C (Sanchez-Partida et al. 2000, Biol. Reprod. 63, 1092-1097); and Method D (Isachenko et al. 2005 Reprod. Biomed. Online 10, 350-354). Protocols were followed according to each published technique. Upon thawing, each sample was split into different incubation conditions: 37�C, 5% CO2 in air or room temperature for 0-24 h. One dose of activators was used according to standard protocol. Statistical analyses of motility rates were performed using 2 � 2 G tests (Sokal and Rohlf 1981 Biometry. New York: W. H. Freeman Co.) to determine significance. Samples cryopreserved using method D did not survive the method (motility = 0) and were not included in the statistical analysis. Methods A-C all demonstrated reasonable post-thaw motility recovery rates (68%, 73%, and 62%, respectively) and underwent capacitation within 30 min of exposure to activators. Sperm motility decreased over time in culture within each treatment at 37�C. However, spermatozoa in Method A were significantly less motile at 4 and 24 h than those in Methods B and C, and Method B spermatozoa were significantly less motile at 24 h than those in Method C. Sperm motility also decreased over time in samples incubated at room temperature, with motility of sperm in Method A motility being significantly less at 24 h than that of sperm in Methods B and C. Method C best preserved motility over time regardless of temperature of incubation upon thawing. Overall, incubation at room temperature preserved motility better than incubation at 37�C. Methods A-C yielded satisfactory post-thaw recovery of progressively motile spermatozoa despite the various differences among their protocols. For long-term use of each sample, however, it would be beneficial to incubate spermatozoa at room temperature after using Method C. This technique appears to be more appropriate for gene banking rhesus semen, and applying this protocol would allow more efficient usage of each semen sample, potentially providing for multiple IVF cases over a 24-h period. This work was supported by NIH Grant RR15395.

Socio-demographic and health system factors in relation to exclusive breast-feeding in Tobago

To determine the prevalence and significant correlates of exclusive breast-feeding among nursing mothers, we conducted a survey among nursing mothers attending the Wellness Baby Clinic in Tobago from July 1 to December 1, 1998. A random sample of 151 mothers had face-to-face interviews with a standardized pretested questionnaire. Our results suggest that 48.3% and 20.8% of infants were exclusively breast-fed at two and four months respectively. Univariate logistic regression analyses showed that exclusive breast-feeding at two months was significantly positively associated with years of schooling completed by the mother, frequency of prenatal visits, mode of breast-feeding, mother's knowledge of the recommended duration of breast-feeding, and occupation of the child's father. Exclusive breast-feeding at four months was significantly positively associated with mother's age, years of schooling completed by the mother, frequency of prenatal visits, mother's knowledge of the recommended duration of breast-feeding, years of schooling completed by the child's father and occupation of the child's father. In multivariate logistic analyses, adjusting simultaneously for all relevant explanatory variables, exclusive breast-feeding at two months was significantly positively associated with frequency of prenatal clinic visits, mode of breast-feeding, mother's knowledge of the recommended duration of breast-feeding and occupation of the child's father. In addition, exclusive breast-feeding at four months was significantly positively associated with frequency of prenatal clinic visits, length of hospital stay, mother's knowledge of recommended duration of breast-feeding, years of schooling completed by the child's father, family structure and inversely associated with mother's age. In this sample, parental socio-demographic characteristics and health system factors were associated with subsequent infant feeding practices.

Comprehensive evaluation of patients with haematuria on multi-slice computed tomography scanner: protocol design and preliminary observations

An imaging protocol with a multi-slice CT scanner that allows comprehensive assessment of patients with haematuria is described. This protocol allows evaluation of the kidneys, ureters and bladder in a single examination using CT. This approach should streamline the diagnostic work-up of patients with haematuria.

Diagnosis of primary HIV-1 infection. Los Angeles County Primary HIV Infection Recruitment Network

BACKGROUND

The optimal approach for diagnosing primary HIV-1 infection has not been defined.

OBJECTIVE

To determine the usefulness of symptoms and virologic tests for diagnosing primary HIV-1 infection.

DESIGN

Prospective cohort study.

SETTING

A teaching hospital in Los Angeles and a university research center in San Diego, California.

PATIENTS

436 patients who had symptoms consistent with primary HIV infection.

MEASUREMENTS

Clinical information and levels of HIV antibody, HIV RNA, and p24 antigen.

RESULTS

Primary infection was diagnosed in 54 patients (12.4%). The sensitivity and specificity of the p24 antigen assay were 88.7% (95% CI, 77.0% to 95.7%) and 100% (CI, 99.3% to 100%), respectively. For the HIV RNA assay, sensitivity was 100% and specificity was 97.4% (CI, 94.9% to 98.9%). Fever, myalgia, rash, night sweats, and arthralgia occurred more frequently in patients with primary infection (P < 0.05).

CONCLUSIONS

No sign or symptom allows targeted screening for primary infection. Although assays for HIV RNA are more sensitive than those for p24 antigen in diagnosing primary infection, they are more expensive and are more likely to yield false-positive results.

HIV-associated changes in adaptive, emotional, and behavioral functioning in children and adolescents with hemophilia: results from the Hemophilia Growth and Development Study

OBJECTIVE

To assess changes in adaptive, emotional, and behavioral functioning over four years in children and adolescents with hemophilia and with or without HIV infection and to evaluate the relationship of these changes to immune status.

METHODS

Participants were 277 HIV-seropositive and 126 HIV-seronegative boys with hemophilia. Participants with HIV infection were divided into three groups based on trajectory of immune functioning (CD4+ cell counts) over the course of the study. Caregivers completed the Vineland Adaptive Behavior Scales and Pediatric Behavior Scale (PBS).

RESULTS

Results showed declining Vineland Communication scores for participants with consistently poor immune functioning. These participants also started with more PBS Attention Deficit and Deviation symptoms, which then decreased more sharply than for other groups. Low CD4+ counts were consistently associated with more Health and Depression-Anxiety symptoms on the PBS. However, with few exceptions, group means remained within normal limits.

CONCLUSIONS

According to their caregivers, boys with hemophilia and HIV infection showed considerable resilience with regard to adaptive behavior and emotional and behavioral problems. However, over time changes occurred in these areas that appear to be related to immune functioning.

A proposed aquatic plant community biotic index for wisconsin lakes

The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments, Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially have low nutrient levels.

Goal attribution in chimpanzees

Does the chimpanzee attribute goals to others? Recent infant studies using the looking time measure have been interpreted as evidence that human infants attribute goals. An experiment modeled on these studies was carried out on chimpanzees, and the chimpanzees responded the way infants do. This indicates that chimpanzees also attribute goals and hence that this capacity is not distinctively human.

Declining immune function in children and adolescents with hemophilia and HIV infection: effects on neuropsychological performance. Hemophilia Growth and Development Study

OBJECTIVE

To determine whether declines in immune functioning are associated with changes in neuropsychological performance in children and adolescents with hemophilia who are infected with the human immunodeficiency virus (HIV).

METHODS

Participants were 333 males with hemophilia, ages 6-19 years at entry. A baseline and four annual neuropsychological evaluations were given. A longitudinal growth curves analysis of data was performed to detect changes associated with declining immune function. The cohort was stratified into four groups: (1) HIV- (n = 126); (2) HIV+, average of first two and last two CD4 counts > or = 200, (n = 106; High CD4 group); (3) HIV+, average first two counts > or = 200, average last two counts < 200 (n = 41; CD4 Drop group); and (4) HIV+, average first two and last two counts < 200 (n = 60; Low CD4 group).

RESULTS

There were significant differences among the four groups over time in nonverbal intelligence, perceptual/performance skills, nonverbal memory, academic achievement, and language. The Low CD4 group consistently showed the greatest decrement in performance. On measures showing a practice effect for repeated measurements, the Low CD4 group participants' scores remained stable over time, suggesting opposing effects of practice and HIV-related declines. Lowered academic performance relative to IQ was found in all groups.

CONCLUSIONS

Declines in neuropsychological functioning are directly related to declines in immune functioning in HIV+ children, adolescents, and young adults with hemophilia. Hemophilia itself may be a risk factor for academic underachievement.

Attention in HIV-infected children: results from the Hemophilia Growth and Development Study

Attentional functioning was examined in three groups of 7- to 19-year-old male participants with hemophilia: (1) HIV seronegative controls (HIV-, N = 66), (2) HIV seropositive participants with CD4+ lymphocyte counts greater than or equal to 200 (HIV+ CD4+ > or = 200, N = 79), and (3) severely immune suppressed HIV seropositive participants (HIV+ CD4+ < 200, N = 28). Two measures sensitive to attention deficits were used: the Continuous Performance Test (CPT) and the Span of Apprehension (Span). On the CPT, there was a decrement in attention in both HIV+ groups, as indexed by an increase in false alarm rate from Block 1 to Block 3, that was not present in the HIV- group. The longer the HIV+ children were required to sustain attention to the CPT, the more they responded to the incorrect stimulus. This effect decreased as age increased. Span percent correct and latency to correct were associated with the presence of a premorbid history of intracerebral hemorrhage, but were not sensitive to HIV status or degree of immune suppression in the HIV+ children, suggesting morbidity related to hemophilia. The remaining CPT and Span variables--hit rate, sensitivity, latency, percent correct, and latency to correct--showed the expected associations with age, but none showed conclusive associations with HIV status or immune suppression in the HIV+ participants.

A cognitive theory of pretense

Recent accounts of pretense have been underdescribed in a number of ways. In this paper, we present a much more explicit cognitive account of pretense. We begin by describing a number of real examples of pretense in children and adults. These examples bring out several features of pretense that any adequate theory of pretense must accommodate, and we use these features to develop our theory of pretense. On our theory, pretense representations are contained in a separate mental workspace, a Possible World Box which is part of the basic architecture of the human mind. The representations in the Possible World Box can have the same content as beliefs. Indeed, we suggest that pretense representations are in the same representational "code" as beliefs and that the representations in the Possible World Box are processed by the same inference and UpDating mechanisms that operate over real beliefs. Our model also posits a Script Elaborator which is implicated in the embellishment that occurs in pretense. Finally, we claim that the behavior that is seen in pretend play is motivated not from a "pretend desire", but from a real desire to act in a way that fits the description being constructed in the Possible World Box. We maintain that this account can accommodate the central features of pretense exhibited in the examples of pretense, and we argue that the alternative accounts either can't accommodate or fail to address entirely some of the central features of pretense.

Correlations of glutathione peroxidase activity with memory impairment in adults with Down syndrome

BACKGROUND

Down syndrome (DS) is a genetic disorder (trisomy 21 in 96% of cases), associated with an excess of a key enzyme involved with free radical metabolism (FRM), superoxide dismutase-1 (SOD-1), that is encoded by a gene on chromosome 21. Consequently, SOD-1 activity is elevated in DS, which also occurs in conditions of oxidative stress, and is associated with a compensatory increase in glutathione peroxidase activity (GSHPx).

METHODS

This study examined the relationship of memory function with erythrocyte SOD-1, GSHPx and catalase (CAT) activity in 22-51 year old adults with DS.

RESULTS

Mean erythrocyte SOD-1 (p < .02) and GSHPx (p < .01), but not CAT (p = .76), activities were significantly greater in the DS group than the controls. In the DS group, erythrocyte GSHPx, but not SOD-1 or CAT activities, was significantly correlated with memory function (r = .625, p < .025, df = 13 for savings score, r = .631, p < .01, df = 14 for intrusion errors) but not with intelligence quotients.

CONCLUSIONS

These observations suggest a possible relationship between altered FRM with memory deficits among adults with DS within the age-range in that an age-related increase in the prevalence for Alzheimer's neuropathology is known to be robust before reaching a plateau of 100%.