Evidence that the loss of colonic anti-microbial peptides may promote dysbiotic Gram-negative inflammaging-associated bacteria in aging mice

Introduction: Aging studies in humans and mice have played a key role in understanding the intestinal microbiome and an increased abundance of "inflammaging" Gram-negative (Gn) bacteria. The mechanisms underlying this inflammatory profile in the aging microbiome are unknown. We tested the hypothesis that an aging-related decrease in colonic crypt epithelial cell anti-microbial peptide (AMP) gene expression could promote colonic microbiome inflammatory Gn dysbiosis and inflammaging. Methods: As a model of aging, C57BL/6J mice fecal (colonic) microbiota (16S) and isolated colonic crypt epithelial cell gene expression (RNA-seq) were assessed at 2 months (mth) (human: 18 years old; yo), 15 mth (human: 50 yo), and 25 mth (human: 84 yo). Informatics examined aging-related microbial compositions, differential colonic crypt epithelial cell gene expressions, and correlations between colonic bacteria and colonic crypt epithelial cell gene expressions. Results: Fecal microbiota exhibited significantly increased relative abundances of pro-inflammatory Gn bacteria with aging. Colonic crypt epithelial cell gene expression analysis showed significant age-related downregulation of key AMP genes that repress the growth of Gn bacteria. The aging-related decrease in AMP gene expressions is significantly correlated with an increased abundance in Gn bacteria (dysbiosis), loss of colonic barrier gene expression, and senescence- and inflammation-related gene expression. Conclusion: This study supports the proposed model that aging-related loss of colonic crypt epithelial cell AMP gene expression promotes increased relative abundances of Gn inflammaging-associated bacteria and gene expression markers of colonic inflammaging. These data may support new targets for aging-related therapies based on intestinal genes and microbiomes.

Practices and opinions of New Zealand sheep farmers towards pain management in lambs during castration and/or tail docking

AIMS

To collect baseline data from New Zealand sheep farmers on techniques for docking and castrating lambs, their perceptions of the level of pain lambs experience following these procedures, and their opinions about the use of pain relief.

METHODS

From a voluntary cross-sectional survey of New Zealand sheep farmers, descriptive statistics were provided for quantitative study variables. Thematic analysis was performed on the free-text comments. Univariable logistic regression was used to assess factors associated with farmers indicating they would consider using a device allowing administration of pain relief simultaneously with castration and tail docking.

RESULTS

There were 432 survey responses containing sufficiently complete data for analysis. Of the 340 individuals (77.5%) always or sometime performing castration of ram lambs, 242 (72.2%) used rubber rings for complete castration, 23 (6.9%) used the short scrotum method for cryptorchid castration, and 75 (22.4%) used a combination of both methods. Of the 423 individuals (97.9%) who indicated that they always or sometimes performed tail docking, 245 (57.9%) used a hot iron only, 148 (35.0%) used a rubber ring only, 26 (5.8%) used both methods, 3 (0.7%) used a surgical knife, and 1 (0.2%) provided no response. Less than 2% of respondents always or sometimes used pain relief for these procedures. Of the 432 respondents, 139 (32.2%) and 180 (41.7%) strongly agreed that castration and tail docking do not cause sufficient pain to warrant using pain relief, respectively. Time and cost were identified as major barriers to providing pain relief. In the unadjusted logistic regression analyses, respondents who were female, had high levels of education, had been farming < 20 years, who believed lambs experienced high levels of pain following the procedures, and who believed pain lasted longer than 6 hours, were more likely to indicate willingness to use pain control devices.

CONCLUSION AND CLINICAL RELEVANCE

Our results suggest very few New Zealand sheep farmers currently provide lambs with pain relief following tail docking or castration. This is likely due to the perception that the procedures are not painful enough to warrant pain relief, and concern over time and cost. This highlights the need to educate farmers about lamb pain and distress following tail docking and castration, and its negative impact on animal welfare. Farmers also need pain relief techniques and tools that can be administered simultaneously with these procedures to save time and labour cost.

Abstract PO-143: Differences in vitamin D genomic and epigenomic responses in colonic organoids from African- and European-Americans

Background: African Americans have the highest burden of colorectal cancer (CRC) in the US. Active 1,25(OH)2vitamin D (1,25vitD) protects from CRC, though the role of population differences in 1,25vitD responses to CRC disparities is unknown. To study inter-ethnic host-environment interactions in the colon, we have established human-derived colonic organoids from diverse populations. We used this approach to study differences in transcriptional and chromatin accessibility responses to 1,25vitD between Americans of African (AA) and European (EA) ancestry. Methods: Colonic organoids from 60 subjects (30 AA and 30 EA) were established. After passaging, organoids were differentiated for 24h and then treated with 100nM 1,25vitD or ethanol (vehicle control). Chromatin accessibility and gene expression were assessed at 4 and 6 hours by RNA-seq and ATAC-seq, respectively. Inter-ethnic responses were assessed using dream (Hoffman et al, 2020). Genotyping was performed using the Infinium OmniExpress-24, and ancestry was estimated using imputed genotypes. Expression quantitative trait loci (eQTL) mapping was performed using BRIdGE (Maranville et al, 2011). Results: Organoid lines from 54 subjects (28 AA and 26 EA) were included after removing 5 with inconsistent ancestry. For overall 1,25vitD response, 7816 differentially expressed protein-coding genes at a false discovery rate (FDR)&lt;5% were found. Gene set enrichment included the KEGG pathway “colorectal cancer” (FDR&lt;5%) with differentially responsive genes such as APC and MYC. eQTL mapping showed 131 1,25vitD-only and 21 control-only significant variants (FDR&lt;5%). For inter-ethnic 1,25vitD responses, top genes included MORC3, MAP4K3, AMACR, KYNU, PIK3CA and POLB. Results for POLB, a base-excision repair polymerase, were particularly interesting given significant inter-ethnic differences in genomic and epigenomic responses to 1,25vitD likely due to a genetic mechanism. Specifically, organoids from AA showed significantly higher POLB expression with 1,25vitD. In the region, a POLB eQTL, rs2272733, showed large allele frequency differences for the ancestral T allele (80% in Africa; 14% in Europe). This eQTL is located in a POLB enhancer region, and there is a vitamin D-responsive ATAC peak ~10kb 5' to this SNP that is only present in T/T genotypes. Conclusion: Application of organoids from diverse populations enables genome-wide assessment of population differences in host-environment interactions related to CRC. In this study, overall 1,25vitD responses were robust and found pathways relevant to CRC. eQTL mapping further established a genetic basis for 1,25vitD colonic responses. We found a number of genes that showed differences in 1,25vitD transcriptional response between AA and EA with a particularly promising CRC-relevant candidate gene, POLB. These results provide new insights into differences in host-environment interactions between populations that could underlie cancer disparities.

Citation Format: Sonia Kupfer, David Witonsky, Jinchao Li, Margaret Bielski, Kristi Lawrence. Differences in vitamin D genomic and epigenomic responses in colonic organoids from African- and European-Americans [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-143.

Nasopharyngeal carriage of otitis media pathogens in infants receiving 10-valent non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV10), 13-valent pneumococcal conjugate vaccine (PCV13) or a mixed primary schedule of both vaccines: A randomised controlled trial

BACKGROUND

Aboriginal children in Northern Australia have a high burden of otitis media, driven by early and persistent nasopharyngeal carriage of otopathogens, including non-typeable Haemophilus influenzae (NTHi) and Streptococcus pneumoniae (Spn). In this context, does a combined mixed primary series of Synflorix and Prevenar13 provide better protection against nasopharyngeal carriage of NTHi and Spn serotypes 3, 6A and 19A than either vaccine alone?

METHODS

Aboriginal infants (n = 425) were randomised to receive Synflorix™ (S, PHiD-CV10) or Prevenar13™ (P, PCV13) at 2, 4 and 6 months (_SSS or _PPP, respectively), or a 4-dose early mixed primary series of PHiD-CV10 at 1, 2 and 4 months and PCV13 at 6 months of age (SSSP). Nasopharyngeal swabs were collected at 1, 2, 4, 6 and 7 months of age. Swabs of ear discharge were collected from tympanic membrane perforations.

FINDINGS

At the primary endpoint at 7 months of age, the proportion of nasopharyngeal (Np) swabs positive for PCV13-only serotypes 3, 6A, or 19A was 0%, 0.8%, and 1.5% in the _PPP, _SSS, and SSSP groups respectively, and NTHi 55%, 52%, and 52% respectively, and no statistically significant vaccine group differences in other otopathogens at any age. The most common serotypes (in order) were 16F, 11A, 10A, 7B, 15A, 6C, 35B, 23B, 13, and 15B, accounting for 65% of carriage. Ear discharge swabs (n = 108) were culture positive for NTHi (52%), S. aureus (32%), and pneumococcus (20%).

CONCLUSIONS

Aboriginal infants experience nasopharyngeal colonisation and tympanic membrane perforations associated with NTHi, non-PCV13 pneumococcal serotypes and S. aureus in the first months of life. Nasopharyngeal carriage of pneumococcus or NTHi was not significantly reduced in the early 4-dose combined SSSP group compared to standard _PPP or _SSS schedules at any time point. Current pneumococcal conjugate vaccine formulations do not offer protection from early onset NTHi and pneumococcal colonisation in this high-risk population.

Potential Spatial Distribution of the Newly Introduced Long-horned Tick, Haemaphysalis longicornis in North America

The North American distributional potential of the recently invaded tick, Haemaphysalis longicornis, was estimated using occurrence data from its geographic range in other parts of the world and relevant climatic data sets. Several hundred candidate models were built using a correlative maximum entropy approach, and best-fitting models were selected based on statistical significance, predictive ability, and complexity. The median of the best-fitting models indicates a broad potential distribution for this species, but restricted to three sectors—the southeastern United States, the Pacific Northwest, and central and southern Mexico.

Epidemiology of the epidemic of bovine anaemia associated with Theileria orientalis (Ikeda) between August 2012 and March 2014

AIMS

To describe the epidemiology of the epidemic of bovine anaemia associated with Theileria orientalis infection (TABA) in New Zealand between 30 August 2012 and 4 March 2014.

METHODS

Blood samples and associated data were obtained from cases of TABA. The case definition for TABA was met when piroplasms were present on blood smears and the haematocrit was ≤0.24 L/L. Samples were analysed using quantitative PCR (qPCR) assays for the detection of T. orientalis Ikeda type. Only cases that were positive in the qPCR assays were included in the analysis. A case herd was defined as a herd that had ≥1 animal positive for T. orientalis Ikeda. Movement records for farms were accessed through the national animal identification and tracing scheme. The OR for cattle movements onto a case farm compared to a non-case farm was estimated using a generalised estimating equation model and the geodesic distance for movements onto case and non-case farms compared using Student's t-test. The kernel-smoothed risk of disease at the farm level was calculated using an extraction map and the clustering of diseased farms in time and space was measured using the spatial temporal inhomogeneous pair correlation function.

RESULTS

In the first 18 months there were 496 case herds; 392 (79%) were dairy and 104 (21%) beef herds. Of 882 individual cases, 820 (93.0%) were positive for T. orientalis Ikeda in the qPCR assays. Case herds were initially clustered in the Northland, then the Waikato regions. The OR for a case farm compared to a non-case farm having ≥1 inward cattle movements was 2.03 (95% CI=1.52-2.71) and the distance moved was 26 (95% CI=20.8-31.3) km greater for case farms. The risk of disease was highest in a north, north-eastern to south, south-western belt across the Waikato region. The spatial-temporal analysis showed significant clustering of infected herds within 20-30 days and up to 15 km distant from a case farm.

CONCLUSIONS

Theileria orientalis Ikeda type is likely to have been introduced into regions populated with naïve cattle by the movement of parasitaemic cattle from affected areas. Local spread through dispersed ticks then probably became more important for disease transmission between herds once the disease established in a new area.

CLINICAL RELEVANCE

Dairy and beef farming in the North Island of New Zealand will be significantly changed in the coming years by the incursion of this new disease.

Prevalence of Streptococcus dysgalactiae subsp. equisimilis and S. equi subsp. zooepidemicus in a sample of healthy dogs, cats and horses

AIMS

To estimate the prevalence of β-haemolytic Lancefield group C streptococci in healthy dogs, cats and horses; to determine if frequent contact with horses was associated with isolation of these species from dogs and cats; and to characterise recovered S. equi subsp. zooepidemicus isolates by multilocus sequence typing.

METHODS

Oropharyngeal swabs were collected from 197 dogs and 72 cats, and nasopharyngeal swabs from 93 horses. Sampling was carried out at the Massey University Veterinary Teaching Hospital, on sheep and beef farms or on premises where horses were present. All animals were healthy and were categorised as Urban dogs and cats (minimal contact with horses or farm livestock), Farm dogs (minimal contact with horses) and Stable dogs and cats (frequent contact with horses). Swabs were cultured for β-haemolytic Streptococcus spp. and Lancefield group C streptococcal subspecies were confirmed by phenotypic and molecular techniques.

RESULTS

Of the 197 dogs sampled, 21 (10.7 (95% CI= 4.0-25.4)%) tested positive for S. dysgalactiae subsp. equisimilis and 4 (2.0 (95% CI=0.7-5.5)%) tested positive for S. equi subsp. zooepidemicus. All these isolates, except for one S. dysgalactiae subsp. equisimilis isolate in an Urban dog, were from Stable dogs. S. dysgalactiae subsp. equisimilis was isolated from one Stable cat. Of the 93 horses, 22 (23.7 (95% CI=12.3-40.6)%) and 6 (6.5 (95% CI=2.8-14.1)%) had confirmed S. dysgalactiae subsp. equisimilis and S. equi subsp. zooepidemicus isolation respectively. Isolation of S. dysgalactiae subsp. equisimilis from dogs was associated with frequent contact with horses (OR=9.8 (95% CI=2.6-72.8)). Three different multilocus sequence type profiles of S. equi subsp. zooepidemicus that have not been previously reported in dogs were recovered.

CONCLUSIONS AND CLINICAL RELEVANCE

Subclinical infection or colonisation by S. equi subsp. zooepidemicus and S. dysgalactiae subsp. equisimilis occurs in dogs and further research on inter-species transmission and the pathogenic potential of these Lancefield group C streptococci is needed. Complete speciation of β-haemolytic streptococci should be recommended in clinical cases and the possible exposure to horses and their environment should be considered in epidemiological investigations.

An ultra scale-down analysis of the recovery by dead-end centrifugation of human cells for therapy

An ultra scale-down method is described to determine the response of cells to recovery by dead-end (batch) centrifugation under commercially defined manufacturing conditions. The key variables studied are the cell suspension hold time prior to centrifugation, the relative centrifugal force (RCF), time of centrifugation, cell pellet resuspension velocities, and number of resuspension passes. The cell critical quality attributes studied are the cell membrane integrity and the presence of selected surface markers. Greater hold times and higher RCF values for longer spin times all led to the increased loss of cell membrane integrity. However, this loss was found to occur during intense cell resuspension rather than the preceding centrifugation stage. Controlled resuspension at low stress conditions below a possible critical stress point led to essentially complete cell recovery even at conditions of extreme centrifugation (e.g., RCF of 10000 g for 30 mins) and long (∼2 h) holding times before centrifugation. The susceptibility to cell loss during resuspension under conditions of high stress depended on cell type and the age of cells before centrifugation and the level of matrix crosslinking within the cell pellet as determined by the presence of detachment enzymes or possibly the nature of the resuspension medium. Changes in cell surface markers were significant in some cases but to a lower extent than loss of cell membrane integrity. Biotechnol. Bioeng. 2015;112: 997–1011. © 2014 Wiley Periodicals, Inc.

Observations on the incidence and seasonality of uterine torsion and left displaced abomasum following the 2001 outbreak of foot-and-mouth disease in the UK

Time-series impact analysis was used to compare differences in the rate of reporting of left displaced abomasum (LDA) and uterine torsion by veterinarians in the UK before and after an outbreak of foot-and-mouth disease (FMD) in 2001. There were 150% and 35% increases in the reported incidences of LDA and uterine torsion, respectively, following the outbreak. Changes to feeding practices are likely to have been a major contributor to the increased incidence of LDA, but this factor is unlikely to have influenced the changed incidence in uterine torsion. Given that abdominal size and shape of dairy cows are recognised risk factors for both disease processes, the findings of this study suggest changes in these parameters may have a role in the altered incidences. Additional research is required to further elucidate the risk factors contributing to the increased incidence of LDA and uterine torsion in dairy cows under UK conditions.

THE PAPWORTH PLUG - successful use of high dose fibrinogen concentrate and platelet concentrate in potential life-threatening complication after cardiopulmonary bypass surgery in a patient with Type 2M Vicenza von Willebrand Disease

Anecdotally, fibrinogen concentrate (FC) has been used as a "universal" haemostatic agent in complex post-cardiopulmonary bypass (CPB) coagulopathy. We present a case where FC and two pools of platelets prevented life-threatening bleeding in a patient with moderate von Willebrand Disease (vWD) immediately post CPB.

Capture-recapture to estimate completeness of tuberculosis surveillance in two communities in South Africa

BACKGROUND

Reliable surveillance is essential for any tuberculosis (TB) control programme; however, under-registration of TB cases due to under-notification of patients on treatment or failure to initiate treatment has been well-documented internationally.

OBJECTIVE

To determine the contribution of capture-recapture methods in estimating the completeness of bacteriologically confirmed pulmonary TB registration in two high-incident communities in South Africa.

METHODS

Record linkage between the TB treatment register and two laboratory sputum TB result registers and three-source log-linear capture-recapture analysis.

RESULTS

The number of bacteriologically confirmed pulmonary TB cases in the TB treatment register was 243, with an additional 63 cases identified in the two laboratory databases, resulting in 306 TB cases. The observed completeness of the TB treatment register was 79%. The log-linear model estimated 326 (95%CI 314-355) TB cases, resulting in an estimated completeness of registration of 75% (95%CI 68-77).

CONCLUSION

Capture-recapture can be useful in evaluating the completeness of TB control surveillance and registration, including in resource-limited settings; however, methodology and results should be carefully assessed. Interventions are needed to increase the completeness of registration and to reduce the number of initial defaulters.

Administrative incidence of psychosis assessed in an early intervention service in England: first epidemiological evidence from a diverse, rural and urban setting

BACKGROUND

Early Intervention in Psychosis Services (EIS) for young people in England experiencing first-episode psychosis (FEP) were commissioned in 2002, based on an expected incidence of 15 cases per 100 000 person-years, as reported by schizophrenia epidemiology in highly urban settings. Unconfirmed reports from EIS thereafter have suggested higher than anticipated rates. The aim of this study was to compare the observed with the expected incidence and delineate the clinical epidemiology of FEP using epidemiologically complete data from the CAMEO EIS, over a 6-year period in Cambridgeshire, for a mixed rural-urban population.

METHOD

A population-based study of FEP (ICD-10, F10-39) in people aged 17-35 years referred between 2002 and 2007; the denominator was estimated from mid-year census statistics. Sociodemographic variation was explored by Poisson regression. Crude and directly standardized rates (for age, sex and ethnicity) were compared with pre-EIS rates from two major epidemiological FEP studies conducted in urban English settings.

RESULTS

A total of 285 cases met FEP diagnoses in CAMEO, yielding a crude incidence of 50 per 100 000 person-years [95% confidence interval (CI) 44.5-56.2]. Age- and sex-adjusted rates were raised for people from black ethnic groups compared with the white British [incidence rate ratio (IRR) 2.1, 95% CI 1.1-3.8]. Rates in our EIS were comparable with pre-EIS rates observed in more urban areas after age, sex and ethnicity standardization.

CONCLUSIONS

Our findings suggest that the incidence observed in EIS is far higher than originally anticipated and is comparable to rates observed in more urban settings prior to the advent of EIS. Sociodemographic variation due to ethnicity and other factors extend beyond urban populations. Our results have implications for psychosis aetiology and service planning.

Accuracy and completeness of recording of confirmed tuberculosis in two South African communities

BACKGROUND

Although tuberculosis (TB) treatment registers and laboratory records are essential tools for recording and reporting in TB control programmes, the accuracy and completeness of routinely collected data are seldom monitored.

OBJECTIVE

To assess the accuracy and completeness of TB treatment register data in two South African urban communities using record linkage.

METHODS

All cases of bacteriologically confirmed TB, defined as two smear-positive results and/or at least one culture-positive result, were included. Record linkage was performed between three data sources: 1) TB treatment registers, 2) the nearest central laboratory, and 3) the referral hospital laboratory.

RESULTS

The TB treatment registers had 435 TB cases recorded, of which 204 (47%) were bacteriologically confirmed. An additional 39 cases recorded as non-bacteriological cases in the TB treatment registers were reclassified as bacteriologically confirmed, and 63 bacteriologically confirmed cases were identified from the laboratory databases that were not recorded in the TB treatment registers. The final number of bacteriologically confirmed TB cases was 306, giving an increase of 50%.

CONCLUSIONS

The accuracy and completeness of the TB treatment register and central laboratory data were inadequate. A high percentage of bacteriologically confirmed cases from both laboratories were not recorded in the TB treatment registers. We are developing an electronic result management system to improve the management of laboratory results.

Effect of 3 postmortem electrical stimulation treatments on the quality of early deboned broiler breast meat

The present experiment was carried out to evaluate the effects of electrical stimulation (ES) immediately prescalding (PS), ES immediately postdefeathering (PD), or PS combined with PD (PSPD) on the quality of early deboned (2 h) broiler breast muscles, pectoralis major (fillets), and pectoralis minor (tenders). No stimulation, early-deboned (2 h), and 24-h deboned (24 h) fillets were used for the comparison. The 42-d-old broiler carcasses were electrically stimulated with pulsed current at 200 V for 30 s over a 90-s time interval (total of 1 min over 180 s for PSPD), and breast meat was deboned 2 h postmortem. Quality indicators evaluated were CIE L*, a*, and b* color and pH of the raw fillets and cook yields and Warner-Bratzler (WB) shear force of the fillets and tenders. There were no differences in raw fillet color, pH, and cook yields of both the fillets and tenders between the 3 ES treatments. Effects of different ES treatments on meat WB shear force values varied with breast muscles. For the fillets, the average WB shear force values of both the PS and PSPD samples, which were not different from each other, were significantly lower than those of the PD samples. For the tenders, there were no differences in the average shear force values between the 3 ES treatments. Regardless of ES treatment and breast muscle, early deboned broiler breast meat from ES carcasses required significantly less force to shear than the 2-h control. These results indicate that ES can tenderize early deboned poultry breast muscles; however, the effectiveness of ES tenderization varies with ES treatments for the fillets. The PS treatment is more effective in reducing fillet shear values than PD, and there is no further reduction in shear values with PSPD compared with the PS treatment.

Formulations of deet, picaridin, and IR3535 applied to skin repel nymphs of the lone star tick (Acari: Ixodidae) for 12 hours

The efficacies of a 20% 1-methyl-propyl-2- (hydroxyethyl)-1-piperidinecarboxylate (picaridin) spray, 20% 3-(N-acetyl-N-butyl)aminopropionic acid ethyl ester (IR3535) spray, 20% picaridin lotion, 10% IR3535 lotion, and 33% N,N-diethyl-3-methylbenzamide (deet) cream in repelling nymphal lone star ticks, Amblyomma americanum (L.), were determined at 2-h intervals over 12 h using human subjects. A repellent formulation was applied in a 5-cm-wide band encircling a volunteer's lower leg. For each challenge, 70 host-seeking nymphs were released on each volunteer's ankle, and tick locations were recorded 10 min after the ticks were released. Ticks that crawled entirely across the repellent band were considered not repelled. For all formulations and time points, significantly fewer (all P < 0.0001) A. americanum nymphs crossed the treatment bands on the volunteers' ankles than crossed the corresponding area on the untreated control legs. Formulations containing > or = 20% active ingredient were highly effective, with <10% of the ticks crossing through the treatment bands for any challenge during the 12 h. At least 40% of ticks exposed to any formulation for any challenge fell or crawled off the volunteers. There was no difference in effectiveness between the 20% spray and 20% lotion formulations of picaridin. The 10% IR3535 lotion was significantly less effective than the formulations with higher concentrations of repellent. In the formulations tested, deet, picaridin, and IR3535 provided lasting protection against A. americanum.

Formulations of deet, picaridin, and IR3535 applied to skin repel nymphs of the lone star tick (Acari: Ixodidae) for 12 hours

The efficacies of a 20% 1-methyl-propyl-2- (hydroxyethyl)-1-piperidinecarboxylate (picaridin) spray, 20% 3-(N-acetyl-N-butyl)aminopropionic acid ethyl ester (IR3535) spray, 20% picaridin lotion, 10% IR3535 lotion, and 33% N,N-diethyl-3-methylbenzamide (deet) cream in repelling nymphal lone star ticks, Amblyomma americanum (L.), were determined at 2-h intervals over 12 h using human subjects. A repellent formulation was applied in a 5-cm-wide band encircling a volunteer's lower leg. For each challenge, 70 host-seeking nymphs were released on each volunteer's ankle, and tick locations were recorded 10 min after the ticks were released. Ticks that crawled entirely across the repellent band were considered not repelled. For all formulations and time points, significantly fewer (all P < 0.0001) A. americanum nymphs crossed the treatment bands on the volunteers' ankles than crossed the corresponding area on the untreated control legs. Formulations containing > or = 20% active ingredient were highly effective, with <10% of the ticks crossing through the treatment bands for any challenge during the 12 h. At least 40% of ticks exposed to any formulation for any challenge fell or crawled off the volunteers. There was no difference in effectiveness between the 20% spray and 20% lotion formulations of picaridin. The 10% IR3535 lotion was significantly less effective than the formulations with higher concentrations of repellent. In the formulations tested, deet, picaridin, and IR3535 provided lasting protection against A. americanum.

Prediction of delayed treatment response in pulmonary tuberculosis: use of time to positivity values of Bactec cultures

New drugs that can shorten tuberculosis (TB) treatment and target drug resistant strains are urgently needed. A test which could predict patients at risk of a delayed response to treatment would facilitate clinical trials of new anti-tuberculosis drugs. A widely-used test for the assessment of response to treatment is sputum smear examination. Patients who are smear positive after 2 and 3 months of treatment are said to have delayed and significantly delayed treatment responses respectively. Time to positivity (TTP) values of Bactec cultures, from the first 2 weeks of treatment were used to predict delayed and significantly delayed treatment responses in patients with first time pulmonary tuberculosis. Changes in TTP values early in treatment were transformed to a response ratio (r). Values of r that were less than a threshold value (r(c)) indicated patients who were at risk of having delayed or significantly delayed response to treatment. Accuracy of prediction was sensitive to the timing of sputum sampling and adherence to therapy in the first 2 weeks. Based on TTP data from the first 2 weeks of treatment, significantly delayed treatment response could be predicted with a sensitivity of 75% and a specificity of 62% while the positive (PPV) and negative predictive values (NPV) were 14% and 97% respectively. While the high NPV indicates that a large proportion of patients with a satisfactory response to treatment can be reliably identified, the low PPV value underlines the need to use TTP in conjunction with other markers of disease activity to predict unfavourable treatment response in tuberculosis treatment.

Prevalence of self-reported neuropathic pain and impact on quality of life: a prospective representative survey

BACKGROUND

Data on the incidence of neuropathic pain (NeP) in Austria, its general characteristics and consequences for the quality of life (QOL) are still lacking. The prevalence in the United Kingdom is 8%.

METHODS

A representative survey (n=7707) was carried out. Patients with NeP were identified using previously validated criteria and subsequently asked to complete a questionnaire on QOL and detailed pain characteristics.

RESULTS

The prevalence of NeP was 3.3% (n=260). A higher prevalence was found in 41-50-year-olds (26%) and 51-60 year olds (24%). Pain was long lasting (>1 year: 66%; >5 years: 41%) and severe at onset (mean 6.8; numerical rating scale) as well as later (mean 4.7; 20% 8 or higher). Strong or predominant restriction of daily activities was reported in 65%, strong or predominant sleep disturbances in 60%, feelings of depression in 34% and anxiety in 25%.

CONCLUSION

For the first time, data on the prevalence of NeP in Austria are available. Pain patterns in those affected are characteristic and impact on QOL as well as pain intensity are severe.

Squamous Cell Carcinoma of the Bladder following PTFE Implantation

Squamous cell carcinoma of the bladder in non-bilharzial bladder usually presents in the 7th decade and is more common in males than females. An association between recurrent urinary tract infection (UTI) and long-term catheterisation with carcinoma of the bladder has been established with the pathogenesis thought to be due to chronic irritation and inflammation. In our case the patient had been free from recurrent UTI for 15 years prior to developing carcinoma of the bladder.

The development of mental state attributions in women with X-monosomy, and the role of monoamine oxidase B in the sociocognitive phenotype

We hypothesized that women with Turner syndrome (45,X) with a single X-chromosome inherited from their mother may show mentalizing deficits compared to women of normal karyotype with two X-chromosomes (46,X). Simple geometrical animation events (two triangles moving with apparent intention in relation to each other) which usually elicit mental-state descriptions in normally developing people, did not do so to the same extent in women with Turner syndrome. We then investigated the potential role in this deficit played by monoamine oxidase B enzymatic activity. MAO-B activity reflects central serotonergic activity, and by implication the functional integrity of neural circuits implicated in mentalizing. Platelet MAO-B was substantially reduced in Turner syndrome. However, contrary to prediction, in this (relatively small) sample there was no association between MAO-B enzymatic activity and mentalizing skills in participants with and without Turner syndrome.

Severe factor X deficiency due to a homozygous mutation (Cys364Arg) that disrupts a disulphide bond in the catalytic domain

Severe factor X deficiency (<0.01 IU mL(-1)) is a rare disorder producing a major bleeding tendency including umbilical cord, joint and intracranial haemorrhage. We present the first case of a child homozygous for a g.1177T > C missense alteration, predicted to disrupt the catalytic domain, and resulting in severe FX deficiency. The child suffered intracranial haemorrhage and now receives regular prophylaxis with a prothrombin complex concentrate. Our experience and a review of the literature suggest that optimal frequency of dosing is likely to be two or three times weekly and that the risk of thrombosis is very small.

Mycobacterium tuberculosis infection may protect against allergy in a tuberculosis endemic area

BACKGROUND

Epidemiological studies have shown an inverse relation of mycobacterial infection and the frequency of allergic diseases and asthma. Recent evidence suggests that allergic inflammation may be inhibited in the presence of chronic and persistent infections, such as that by Mycobacterium tuberculosis (MTB). The relation of tuberculin skin test (TST) size, an accepted marker of MTB infection and the frequency of allergic disease symptoms has not been reported from an area where MTB infection is endemic.

OBJECTIVE

To investigate the association of TST and allergic disease symptoms, in children living in a tuberculosis (TB) endemic area.

METHODS

In this cross-sectional study, 841 children aged 6-14 years from randomly selected household addresses in two poor communities of Cape Town, South Africa, were investigated with TST and standardized International Study on Asthma and Allergies in Childhood-based questionnaire on allergic disease symptoms.

RESULTS

Children with positive TST (> or =10 mm) were significantly less likely to have allergic disease symptoms, in particular allergic rhinitis (AR) (adjusted odds ratio 0.43; 95% confidence interval 0.24-0.79) than those with negative TST. This association remained significant after adjusting for possible confounders and correcting for the effect of clustering (>1 child per household address) in the sample. There was a significant inverse linear trend in the relation of TST size in millimetre and the frequency of allergic disease symptoms, in particular AR (P<0.001).

CONCLUSIONS

These results of inverse association of strong TST reaction and allergic disease symptoms in children from a TB endemic area are in support of the hypotheses that allergic inflammation may be inhibited by chronic infections, such as MTB.

Prediction of penicillin resistance in Staphylococcus aureus isolates from dairy cows with mastitis, based on prior test results

AIM

To gauge how well prior laboratory test results predict in vitro penicillin resistance of Staphylococcus aureus isolates from dairy cows with mastitis.

METHODS

Population-based data on the farm of origin (n=79), genotype based on pulsed-field gel electrophoresis (PFGE) results, and the penicillin-resistance status of Staph. aureus isolates (n=115) from milk samples collected from dairy cows with mastitis submitted to two diagnostic laboratories over a 6-month period were used. Data were mined stochastically using the all-possible-pairs method, binomial modelling and bootstrap simulation, to test whether prior test results enhance the accuracy of prediction of penicillin resistance on farms.

RESULTS

Of all Staph. aureus isolates tested, 38% were penicillin resistant. A significant aggregation of penicillin-resistance status was evident within farms. The probability of random pairs of isolates from the same farm having the same penicillin-resistance status was 76%, compared with 53% for random pairings of samples across all farms. Thus, the resistance status of randomly selected isolates was 1.43 times more likely to correctly predict the status of other isolates from the same farm than the random population pairwise concordance probability (p=0.011). This effect was likely due to the clonal relationship of isolates within farms, as the predictive fraction attributable to prior test results was close to nil when the effect of within-farm clonal infections was withdrawn from the model.

CONCLUSIONS

Knowledge of the penicillin-resistance status of a prior Staph. aureus isolate significantly enhanced the predictive capability of other isolates from the same farm. In the time and space frame of this study, clinicians using previous information from a farm would have more accurately predicted the penicillin-resistance status of an isolate than they would by chance alone on farms infected with clonal Staph. aureus isolates, but not on farms infected with highly genetically heterogeneous bacterial strains.

Retroperitoneal fibrosis: unusual cause of low back pain

Retroperitoneal fibrosis (RPF) is an uncommon collagen vascular disease with a male predominance. Back pain with no specific radiation pattern is common, and bilateral obstructive uropathy, potentially reversible, is frequently associated with RPF. We report a case of RPF and review its diagnosis and management.

Heat shock protein-56 is induced by cardiotrophin-1 and mediates its hypertrophic effect

Cardiotrophin-1 (CT-1) is an interleukin-6 family cytokine with known protective and hypertrophic effects in the heart. Previous studies have shown that CT-1 treatment increases heat shock protein 70 (hsp70) and heat shock protein 90 (hsp90) levels in cardiac cells. Due to the known protective effects of hsp90 and hsp70, induction of these proteins may be involved in the protective effects of CT-1. We show here that heat shock protein 56 (hsp56), also known as FK506 binding protein 59 (FKBP59), is induced by CT-1 treatment at both the mRNA and protein levels. It has been demonstrated previously that, unlike hsp70 and hsp90, hsp56 overexpression does not protect cardiac myocytes against stressful stimuli. The other known effect of CT-1 is hypertrophy, an increase in cell size without cell division, which occurs in many cardiac pathologies. We investigated the role of hsp56 in the hypertrophic response of primary neonatal rat cardiac myocytes, using overexpression with transiently transfected plasmid vectors and Herpes viral vectors. Overexpression of hsp56 caused a significant increase in cardiac cell size and protein:DNA ratio. Hsp27, hsp70 and hsp90 overexpression had no effect on cell size. An antisense construct to hsp56 reduced hsp56 levels when transiently transfected and blocked the hypertrophic effect of CT-1. This is the first time that a hypertrophic effect has been demonstrated for a heat shock protein and demonstrates that CT-1-induced hypertrophy involves a specific hsp, which is not involved in its protective effect.

A simian human immunodeficiency virus with a nonfunctional Vpu (deltavpuSHIV(KU-1bMC33)) isolated from a macaque with neuroAIDS has selected for mutations in env and nef that contributed to its pathogenic phenotype

Previous studies have shown that passage of nonpathogenic SHIV-4 through a series of macaques results in the selection of variants of the virus that are capable of causing rapid subtotal loss of CD4(+) T cells and AIDS within 6-8 months following inoculation into pig-tailed macaques. Using a pathogenic variant of SHIV-4 known as SHIV(KU-1bMC33), we reported that a mutant of this virus with the majority of the vpu deleted was still capable of causing profound CD4(+) T cell loss and neuroAIDS in pig-tailed macaques (McCormick-Davis et al., 2000, Virology 272, 112-116). In this study, we have analyzed the tissue-specific changes in the env and nef in one macaque that developed neuroAIDS (macaque 50 O) and in three macaques that developed only a moderate or no significant loss of CD4(+) T cells and no neurological disease (macaques 50 Y, 20220, 20228) following inoculation with DeltavpuSHIV(KU-1bMC33). Sequence analysis of the gp120 region of env isolated from lymphoid tissues (lymph node and spleen) of macaques 50 Y, 20220, and 20228 revealed no consensus amino acid substitutions. In contrast, analysis of the gp120 sequences isolated from lymphoid and CNS tissues (parietal cortex, basal ganglia, and pons) of macaque 50 O revealed numerous amino acid substitutions. The significance of the amino acid substitutions in gp120 was supported by neutralization assays which showed that the virus isolated from the lymph node of macaque 50 O was neutralization resistant compared to the parental SHIV(KU-1bMC33). Analysis of changes in the nef gene from macaque 50 O revealed in-frame deletions in Nef that ranged from 4 to 13 amino acids in length, whereas the nef genes isolated from the other three macaques revealed no deletions or consensus amino acid substitutions. Inoculation of the virus isolated from the lymph node of the macaque which developed neuroAIDS, SHIV(50OLNV), into four pig-tailed macaques resulted in a severe loss of the circulating CD4(+) T cells within 2 weeks postinoculation, which was maintained for up to 20 weeks postinoculation, confirming that this virus had indeed become more pathogenic in pig-tailed macaques. Taken together, these observations suggest that DeltavpuSHIV(KU-1bMC33) has a low pathogenic phenotype in macaques but that individual pig-tailed macaques can select for additional mutations within the Env and Nef which can compensate for the lack of an intact Vpu and ultimately increase its pathogenicity.

Posttransplant diabetes mellitus in pediatric thoracic organ recipients receiving tacrolimus-based immunosuppression

BACKGROUND

Posttransplantation diabetes mellitus (PTDM) is a well-known complication of tacrolimus-based immunosuppression in both adult and pediatric solid organ recipients. The "natural history" of diabetes in the pediatric thoracic transplant population has not yet been described.

METHODS

We identified all pediatric thoracic transplant patients receiving tacrolimus-based immunosuppression who developed PTDM. Medical records were reviewed, with a particular focus on the clinical course of PTDM and its relationship to drug weaning.

RESULTS

Diabetes developed in 24 of 143 (17%) 30-day survivors of heart (12/96, 13%) and heart-lung/lung (12/ 47, 26%) transplantation. In 17 (71%) patients, the immunosuppressive regimen at the onset of PTDM also included maintenance corticosteroids. Seventeen patients demonstrated glucose intolerance before the onset of diabetes. Nine patients (38%) developed diabetes during pulsed corticosteroid therapy. Median time of onset after transplantation was 9.0 months. All patients required s.c. insulin for glucose control. The median follow-up from transplant was 49.9 months. There was a significant decrease in mean tacrolimus dosage (P<0.01), tacrolimus level (P<0.04), and steroid dosage (P<0.02) from onset of PTDM to most recent follow-up. Despite this significant reduction in immunosuppression, only 3/24 (13%) patients were successfully weaned off insulin.

CONCLUSIONS

Diabetes mellitus is a common complication in pediatric thoracic transplant patients receiving tacrolimus-based immunosuppression. Insulin dependence in our population rarely resolved, even after lowering tacrolimus and steroid doses. Discontinuation of steroids did not guarantee resolution of diabetes.

Cardiotrophin-1 reduces stress-induced heat shock protein production in cardiac myocytes

Cardiotrophin-1 (CT-1) can induce expression of the protective heat shock proteins (hsps) in cardiac cells. We show here that, unlike the stress induced accumulation of hsps, the effect of CT-1 is not accompanied by increased hsp mRNA levels and is insensitive to the RNA synthesis inhibitor actinomycin D, suggesting that it occurs at the post-transcriptional level. Pre-treatment with CT-1 reduces the ability of heat shock to induce hsp expression and this effect occurs at the transcriptional level. Hence, CT-1 and stress induce the hsps via different pathways which can antagonise one another. The mechanisms of these effects and their potential impact on the use of CT-1 as a cardioprotective agent are discussed.

Sonographic evaluation of the thenar compartment musculature

The thenar region was studied with ultrasonography in 10 healthy volunteers. All thenar muscles could be identified and their course followed entirely. In addition, their function could be assessed by scanning during unresisted or resisted active movements. Standard approach, normal appearance, and dynamic tests for each muscle are described.

A reduced estimate of the number of kilometre-sized near-Earth asteroids

Near-Earth asteroids are small (diameters < 10 km), rocky bodies with orbits that approach that of the Earth (they come within 1.3 AU of the Sun). Most have a chance of approximately 0.5% of colliding with the Earth in the next million years. The total number of such bodies with diameters > 1 km has been estimated to be in the range 1,000-2,000, which translates to an approximately 1% chance of a catastrophic collision with the Earth in the next millennium. These numbers are, however, poorly constrained because of the limitations of previous searches using photographic plates. (One kilometre is below the size of a body whose impact on the Earth would produce global effects.) Here we report an analysis of our survey for near-Earth asteroids that uses improved detection technologies. We find that the total number of asteroids with diameters > 1 km is about half the earlier estimates. At the current rate of discovery of near-Earth asteroids, 90% will probably have been detected within the next 20 years.

Utilization of health care resources by obese Canadians

BACKGROUND

The prevalence of obesity in Canada has been increasing in recent years. Using data from the National Population Health Survey (NPHS), the authors determined the prevalence of obesity among Canadians, the associated comorbidities and the patterns of resource utilization by obese people.

METHODS

The NPHS, a cross-sectional survey conducted in 1994, was administered to 17,626 Canadians 12 years of age or older who were not long-term residents of hospitals or long-term care facilities and were not residing on First Nations reserves or Canadian Armed Forces bases, or in the Yukon and Northwest Territories. For the authors' analysis, the study population consisted of 12,318 Canadians aged 20-64 years who were not pregnant and for whom the body mass index (BMI) had been calculated. The prevalence of comorbidities, health status index scores, self-esteem, self-rated health, restriction of activity, health care resource utilization (physician visits, disability days, admissions to hospital and medication use) were determined for obese people (BMI of 27 or greater) and nonobese people.

RESULTS

The NPHS data revealed that 35.2% of men and 25.8% of women in Canada were obese in 1994. Obese respondents were more likely than nonobese respondents to suffer from stress (adjusted odds ratio [OR] 1.20, 95% confidence interval [CI] 1.11-1.31), activity restrictions (adjusted OR 1.39, 95% CI 1.26-1.54) and a number of chronic comorbidities. Obese respondents were also more likely to consult with physicians (adjusted OR 1.32, 95% CI 1.22-1.43), be prescribed a number of medications and to require excess disability days (adjusted OR 1.22, 95% CI 1.08-1.36).

INTERPRETATION

Obesity represents a substantial burden on the health of Canadians and on Canada's health care resources.