Molecular Features of Cancers Exhibiting Exceptional Responses to Treatment

A small fraction of cancer patients with advanced disease survive significantly longer than patients with clinically comparable tumors. Molecular mechanisms for exceptional responses to therapy have been identified by genomic analysis of tumor biopsies from individual patients. Here, we analyzed tumor biopsies from an unbiased cohort of 111 exceptional responder patients using multiple platforms to profile genetic and epigenetic aberrations as well as the tumor microenvironment. Integrative analysis uncovered plausible mechanisms for the therapeutic response in nearly a quarter of the patients. The mechanisms were assigned to four broad categories-DNA damage response, intracellular signaling, immune engagement, and genetic alterations characteristic of favorable prognosis-with many tumors falling into multiple categories. These analyses revealed synthetic lethal relationships that may be exploited therapeutically and rare genetic lesions that favor therapeutic success, while also providing a wealth of testable hypotheses regarding oncogenic mechanisms that may influence the response to cancer therapy.

The Exceptional Responders Initiative: Feasibility of a National Cancer Institute Pilot Study

BACKGROUND

Tumor molecular profiling from patients experiencing exceptional responses to systemic therapy may provide insights into cancer biology and improve treatment tailoring. This pilot study evaluates the feasibility of identifying exceptional responders retrospectively, obtaining pre-exceptional response treatment tumor tissues, and analyzing them with state-of-the-art molecular analysis tools to identify potential molecular explanations for responses.

METHODS

Exceptional response was defined as partial (PR) or complete (CR) response to a systemic treatment with population PR or CR rate less than 10% or an unusually long response (eg, duration >3 times published median). Cases proposed by patients' clinicians were reviewed by clinical and translational experts. Tumor and normal tissue (if possible) were profiled with whole exome sequencing and, if possible, targeted deep sequencing, RNA sequencing, methylation arrays, and immunohistochemistry. Potential germline mutations were tracked for relevance to disease.

RESULTS

Cases reflected a variety of tumors and standard and investigational treatments. Of 520 cases, 476 (91.5%) were accepted for further review, and 222 of 476 (46.6%) proposed cases met requirements as exceptional responders. Clinical data were obtained from 168 of 222 cases (75.7%). Tumor was provided from 130 of 168 cases (77.4%). Of 117 of the 130 (90.0%) cases with sufficient nucleic acids, 109 (93.2%) were successfully analyzed; 6 patients had potentially actionable germline mutations.

CONCLUSION

Exceptional responses occur with standard and investigational treatment. Retrospective identification of exceptional responders, accessioning, and sequencing of pretreatment archived tissue is feasible. Data from molecular analyses of tumors, particularly when combining results from patients who received similar treatments, may elucidate molecular bases for exceptional responses.

Chest imaging representing a COVID-19 positive rural U.S. population

As the COVID-19 pandemic unfolds, radiology imaging is playing an increasingly vital role in determining therapeutic options, patient management, and research directions. Publicly available data are essential to drive new research into disease etiology, early detection, and response to therapy. In response to the COVID-19 crisis, the National Cancer Institute (NCI) has extended the Cancer Imaging Archive (TCIA) to include COVID-19 related images. Rural populations are one population at risk for underrepresentation in such public repositories. We have published in TCIA a collection of radiographic and CT imaging studies for patients who tested positive for COVID-19 in the state of Arkansas. A set of clinical data describes each patient including demographics, comorbidities, selected lab data and key radiology findings. These data are cross-linked to SARS-COV-2 cDNA sequence data extracted from clinical isolates from the same population, uploaded to the GenBank repository. We believe this collection will help to address population imbalance in COVID-19 data by providing samples from this normally underrepresented population.

Measurement(s)	COVID-19 image features • chest • viral genome
Technology Type(s)	Radiograph • computed tomography • whole genome sequencing
Factor Type(s)	COVID-19 diagnosis
Sample Characteristic - Organism	Homo sapiens • SARS-CoV-2
Sample Characteristic - Environment	rural area
Sample Characteristic - Location	United States of America

Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12980795

Chest imaging representing a COVID-19 positive rural U.S. population

As the COVID-19 pandemic unfolds, radiology imaging is playing an increasingly vital role in determining therapeutic options, patient management, and research directions. Publicly available data are essential to drive new research into disease etiology, early detection, and response to therapy. In response to the COVID-19 crisis, the National Cancer Institute (NCI) has extended the Cancer Imaging Archive (TCIA) to include COVID-19 related images. Rural populations are one population at risk for underrepresentation in such public repositories. We have published in TCIA a collection of radiographic and CT imaging studies for patients who tested positive for COVID-19 in the state of Arkansas. A set of clinical data describes each patient including demographics, comorbidities, selected lab data and key radiology findings. These data are cross-linked to SARS-COV-2 cDNA sequence data extracted from clinical isolates from the same population, uploaded to the GenBank repository. We believe this collection will help to address population imbalance in COVID-19 data by providing samples from this normally underrepresented population.

Allodynia and descending pain modulation in migraine: a resting state functional connectivity analysis

OBJECTIVE

Most migraineurs develop cutaneous allodynia during migraines, and many have cutaneous sensitization between attacks. Atypical pain modulation via the descending pain system may contribute to this sensitization and allodynia. The objective of this study was to test the hypothesis that compared with non-allodynic migraineurs, allodynic migraineurs have atypical periaqueductal gray (PAG) and nucleus cuneiformis (NCF) resting-state functional connectivity (rs-fc) with other pain processing regions.

DESIGN

Ten minutes resting-state blood-oxygen-level-dependent data were collected from 38 adult migraineurs and 20 controls. Seed-based analyses compared whole-brain rs-fc with PAG and with NCF in migraineurs with severe ictal allodynia (N = 8) to migraineurs with no ictal allodynia (N = 8). Correlations between the strength of functional connections that differed between severely allodynic and non-allodynic migraineurs with allodynia severity were determined for all migraineurs (N = 38). PAG and NCF rs-fc in all migraineurs was compared with rs-fc in controls.

RESULTS

Migraineurs with severe allodynia had stronger PAG and NCF rs-fc to other brainstem, thalamic, insula and cerebellar regions that participate in discriminative pain processing, as well as to frontal and temporal regions implicated in higher order pain modulation. Evidence that these rs-fc differences were specific for allodynia included: 1) strong correlations between some rs-fc strengths and allodynia severity among all migraineurs; and 2) absence of overlap when comparing rs-fc differences in severely allodynic vs non-allodynic migraineurs with those in all migraineurs vs controls.

CONCLUSION

Atypical rs-fc of brainstem descending modulatory pain regions with other brainstem and higher order pain-modulating regions is associated with migraine-related allodynia.

Determination of neural state classification metrics from the power spectrum of human ECoG

Brain electrical activity exhibits scale-free dynamics that follow power law scaling. Previous works have shown that broadband spectral power exhibits state-dependent scaling with a log frequency exponent that systematically varies with neural state. However, the frequency ranges which best characterize biological state are not consistent across brain location or subject. An adaptive piecewise linear fitting solution was developed to extract features for classification of brain state. Performance was evaluated by comparison to an a posteriori based feature search method. This analysis, using the 1/ƒ characteristics of the human ECoG signal, demonstrates utility in advancing the ability to perform automated brain state discrimination.

Atypical resting-state functional connectivity of affective pain regions in chronic migraine

OBJECTIVE

Chronic migraineurs (CM) have painful intolerances to somatosensory, visual, olfactory, and auditory stimuli during and between migraine attacks. These intolerances are suggestive of atypical affective responses to potentially noxious stimuli. We hypothesized that atypical resting-state functional connectivity (rs-fc) of affective pain-processing brain regions may associate with these intolerances. This study compared rs-fc of affective pain-processing regions in CM with controls.

METHODS

Twelve minutes of resting-state blood oxygenation level-dependent data were collected from 20 interictal adult CM and 20 controls. Rs-fc between 5 affective regions (anterior cingulate cortex, right/left anterior insula, and right/left amygdala) with the rest of the brain was determined. Functional connections consistently differing between CM and controls were identified using summary analyses. Correlations between number of migraine years and the strengths of functional connections that consistently differed between CM and controls were calculated.

RESULTS

Functional connections with affective pain regions that differed in CM and controls included regions in anterior insula, amygdala, pulvinar, mediodorsal thalamus, middle temporal cortex, and periaqueductal gray. There were significant correlations between the number of years with CM and functional connectivity strength between the anterior insula with mediodorsal thalamus and anterior insula with periaqueductal gray.

CONCLUSION

CM is associated with interictal atypical rs-fc of affective pain regions with pain-facilitating and pain-inhibiting regions that participate in sensory-discriminative, cognitive, and integrative domains of the pain experience. Atypical rs-fc with affective pain regions may relate to aberrant affective pain processing and atypical affective responses to painful stimuli characteristic of CM.

Abstract P5-14-04: Alleviate the pain in the system: Using process improvement and systems design tools to strive for a high quality breast healthcare system in the District of Columbia metro area

Background: Throughout the District of Columbia Metro Area, breast cancer mortality rates are higher than the national average due in part to limited service coordination and lack of access to breast health services along the continuum. The Primary Care Coalition of Montgomery County (PCC) and the Regional Primary Care Coalition (RPCC) are collaborating to improve the efficiency and effectiveness of breast cancer screening, referral, and follow-up so that jurisdictions and clinics in the DC metro area are better positioned to provide 100% low-income women residents with access to breast healthcare. The Regional Initiative builds upon the successes of the PCC Breast Healthcare Process Improvement Project.

Objectives: 1) Adopt the Primary Care-Based Model in three clinics in three other jurisdictions and implement process improvement approaches to show improvements in breast cancer screening, referral, and follow-up; and 2) Develop a cross-jurisdiction learning community to enhance spread throughout the Region.

Methods: The Regional Initiative employs a multi-tiered learning community framework to share data, address systems level barriers, and design new systems for the provision of high-quality care regardless of insurance status. Partners use the Model for Improvement to improve processes at the micro-system level and system design theory drives larger systems changes.

Results: Objective 1: The three adaptation sites represent Prince Georges County, Maryland, Washington, DC, and Fairfax Virginia. After a year of focused process improvement, partnership development, and data collection, initial analysis demonstrates: – All three clinics show increased screening rates approaching 65%, representing the 90th percentile performance in the Healthcare Effectiveness Data and Information Set (HEDIS) for Medicaid breast cancer screening.– At Greater Baden Medical Services in Prince Georges County, Maryland, cycle time between referral and mammography screening decreased from 48 to 27 days.– The Community Health Care Network, Fairfax County, Virginia, worked closely with one mammography provider to decrease the no-show rate for mammography appointments from 26% to 6%.– The Project Team developed a change package to share recommended interventions and successful strategies that have been tested and documented, and can be used by clinics certified as primary care medical homes or in the process of adopting those standards.

Objective 2: The Cross-Jurisdiction Learning Collaborative brings representatives from each jurisdiction together to share breast health measures, success stories, and plan/discuss process improvement activities from a regional perspective. Participants include over 50 breast health providers from around the region: – 17 safety-net clinics– 11 hospital and/or mammography providers– All County and/or State National Breast and Cervical Cancer Early Detection Programs in the Region

Next Steps: Spread learnings regionally and nationally to foster collaboration, replicate the PCC Primary Care-Based Model using the change package, and further improve breast health outcomes for the safety-net population.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-14-04.

Seroprevalence of 2009 pandemic influenza A(H1N1) virus in Australian blood donors, October - December 2009

Assessment of the severity of disease due to the 2009 pandemic influenza A(H1N1) in Australian states and territories has been hampered by the absence of denominator data on population exposure. We compared antibody reactivity to the pandemic virus using haemagglutination inhibition assays performed on plasma specimens taken from healthy adult blood donors (older than 16 years) before and after the influenza pandemic that occurred during the southern hemisphere winter. Pre-influenza season samples (April – May 2009, n=496) were taken from donation collection centres in North Queensland (in Cairns and Townsville); post-outbreak specimens (October – November 2009, n=779) were from donors at seven centres in five states. Using a threshold antibody titre of 40 as a marker of recent infection, we observed an increase in the influenza-seropositive proportion of donors from 12% to 22%, not dissimilar to recent reports of influenza A(H1N1)-specific immunity in adults from the United Kingdom. No significant differences in seroprevalence were observed between Australian states, although the ability to detect minor variations was limited by the sample size. On the basis of these figures and national reporting data, we estimate that approximately 0.23% of all individuals in Australia exposed to the pandemic virus required hospitalisation and 0.01% died. The low seroprevalence reported here suggests that some degree of prior immunity to the virus, perhaps mediated by broadly reactive T-cell responses to conserved influenza viral antigens, limited transmission among adults and thus constrained the pandemic in Australia.

Sources of non-physiologic noise in simultaneous EEG-fMRI data: a phantom study

Simultaneous EEG-fMRI studies require an understanding of the noise characteristics of the acquisition environment so that appropriate pre-processing steps may be taken to remove known artifacts from the data stream. Using a phantom approach, we have developed a general methodology for characterizing non-physiologic noise in EEG signal and demonstrate the use of this methodology for a specific MR scanner and EEG data acquisition system configuration. Our results show the δ frequency band is significantly impacted by baseline drift or baseline correction algorithms while the β and γ bands are impacted by residual gradient artifact and gradient corrections.

Body dimensions, exercise capacity and physical activity level of adolescent Nandi boys in western Kenya

The aim of this study was to characterize untrained Nandi boys (mean age 16.6 years) from a town (n = 11) and from a rural area (n = 19) in western Kenya (altitude approximately 2000 m.a.s.l.) in regard to their body dimensions, oxygen uptake and physical activity level. The town boys had a mean maximal oxygen uptake (VO(2 max)) of 50 (range: 45-60) mL kg(-1) min(-1), whereas the village boys reached a value of 55 (37-63) mL kg(-1) min(-1) ( p<0.01) in VO(2 max). The running economy, determined as the oxygen cost at a given running speed, was 221 mL kg(-1) km(-1) (597 mL kg(-0.75) km(-1)) for town as well as for village boys. The body mass index (BMI) was very low for town as well as for village boys (18.6 vs 18.4 kg m(-2)). The daily mean time spent working in the field during secondary school and doing sports were significantly higher in village boys compared to town boys (working in the field: 44.2 (0-128) vs 1.3 (0-11) min, p<0.01; sports: 32.0 (11-72) vs 12.8 (0-35) min, p<0.01, respectively). A positive correlation between the daily time spent doing sports and VO(2 max) was found when pooling the data from the town and the village boys (R = 0.55, p<0.01). It is concluded that the body dimensions of adolescent Nandi town and village boys corresponds well with findings in Kenyan elite runners. They are very slender with relatively long legs. In addition, the VO(2 max) of the village boys was higher than that of the town boys, which is probably due to a higher physical activity level of the village boys during secondary school.

Clinical trial experience with prophylactic HPV 6/11/16/18 VLP vaccine in young women from the Asia-Pacific region

OBJECTIVE

To evaluate results of three phase 3 clinical trials of quadrivalent HPV 6/11/16/18 vaccination of young Asia-Pacific women.

METHODS

A total of 814 women from the Asia-Pacific region (aged 16 to 26 years) received vaccine or placebo in 1 of 3 protocols. Descriptive analyses focused on the efficacy, safety, and immunogenicity of the vaccine and the natural history of HPV disease.

RESULTS

Vaccine efficacy against disease caused by HPV types 6, 11, 16, or 18 was 100% for cervical intraepithelial neoplasia (0 vs 12 cases; 95% confidence interval [CI], 63.1%-100%) and 100% for vulvar and vaginal intraepithelial neoplasia or condylomata accuminata (0 vs 5 cases; 95% CI, -11.8% to 100%). The vaccination was highly immunogenic. Vaccine recipients experienced a significantly higher injection site adverse event rate (P=0.002). Compared with other world regions, lower rates of smoking and baseline positivity to 14 HPV types (including the vaccine types) were observed among Asia-Pacific participants.

CONCLUSION

Prophylactic quadrivalent HPV 6/11/16/18 vaccination of young Asia-Pacific women demonstrated high efficacy, safety, and tolerability. Together with an observed low baseline HPV positivity rate, the Asia-pacific population is potentially an important cohort to benefit from vaccination.

Randomized, double-blind study comparing the efficacy of moderate-dose metoclopramide and ondansetron for the prophylactic control of postoperative vomiting in children after tonsillectomy

BACKGROUND

Postoperative vomiting (POV) is a major cause of morbidity after tonsillectomy in children. It has been well established that anti-serotinergic agents are effective for the prophylactic control of POV in this patient group. It has been suggested that at moderate doses (0.5 mg kg(-1)), metoclopramide is also an effective agent. No study has been performed comparing the efficacy of an anti-serotinergic agent and moderate-dose metoclopramide.

METHODS

A total of 557 children undergoing tonsillectomy with or without adenoidectomy were randomly allocated to receive either ondansetron 0.1 mg kg(-1) or metoclopramide 0.5 mg kg(-1). All received a standardized muscle-relaxant anaesthetic and dexamethasone 0.1 mg kg(-1). The primary outcome was any vomit in the immediate postoperative period. Comparisons were made of the proportion in each group reaching the primary outcome and the time until their first vomit. The study was designed to detect equivalence.

RESULTS

The incidence of vomiting in the group receiving ondansetron (25.3%) was 12% lower (95% CI 4.4-19.7) than those in metoclopramide (37.3%). The time until first vomit was significantly longer in the group receiving ondansetron (hazard ratio 0.61, 95% CI 0.45-0.82).

CONCLUSIONS

Although the incidence of vomiting was similar, when these results are compared with a pre-specified zone of equivalence of 0-15%, it cannot be concluded that the effect of metoclopramide is equivalent to ondansetron. Survival analysis indicated that those in the metoclopramide group vomited substantially earlier. It is concluded, therefore, that ondansetron 0.1 mg kg(-1) is a superior drug to metoclopramide 0.5 mg kg(-1) for the prophylactic control of POV in children undergoing tonsillectomy.

Prophylaxis of postoperative vomiting in children undergoing tonsillectomy: a systematic review and meta-analysis

Postoperative vomiting (POV) remains one of the commonest causes of significant morbidity after tonsillectomy in children. A variety of prophylactic anti-emetic interventions have been reported, but there has only been a limited systematic review in this patient group. A systematic search was performed by using Cochrane Controlled Trials Register, MEDLINE and EMBASE to identify double-blind, randomized, placebo-controlled trials of prophylactic anti-emetic interventions in children undergoing tonsillectomy, with or without adenoidectomy. The outcome of interest was POV in the first 24 h. Summary estimates of the effect of each prophylactic anti-emetic strategy were derived using fixed effect meta-analysis. Where appropriate, dose-response effects were estimated using logistic regression and 22 articles were identified. Good evidence was found for the prophylactic anti-emetic effect of dexamethasone [odds ratio (OR) 0.23, 95% CI 0.16-0.33], and the serotinergic antagonists ondansetron (OR 0.36, 95% CI 0.29-0.46), granisetron (OR 0.11, 95% CI 0.06-0.19), tropisetron (OR 0.15, 95% CI 0.06-0.35) and dolasetron (OR 0.25, 95% CI 0.1-0.59). Metoclopramide was also found to be efficacious (OR 0.51, 95% CI 0.34-0.77). There is not sufficient evidence to suggest that dimenhydrinate, perphenazine or droperidol, in the doses studied, are efficacious, nor were gastric aspiration or acupuncture. In conclusion, dexamethasone and the anti-serotinergic agents appear to be the most effective agents for the prophylaxis for POV in children undergoing tonsillectomy.

A comparison of booster immunisation with a combination DTPa-IPV vaccine or DTPa plus IPV in separate injections when co-administered with MMR, at age 4–6 years

This study evaluated GSK's combined DTPa-IPV vaccine (Infanrix-IPV) given as a fifth consecutive acellular pertussis booster dose in conjunction with the second dose of MMR vaccine (Priorix) in children aged 4-6 years. The immunogenicity and reactogenicity of this vaccine regimen was compared with separate injections of DTPa and IPV when given concomitantly with MMR. A cohort of 362 children previously primed with four doses of DTPa and OPV, and a single dose of MMR were randomized to receive either DTPa-IPV+MMR (N=181) or DTPa+IPV+MMR (N=181). Antibody concentrations were measured prior to and 1 month after the booster dose. After immunisation all subjects from both groups had seroprotective antibody levels against diphtheria, tetanus and the three poliovirus serotypes, > or = 96% showed vaccine response to PT, FHA and PRN, all were seropositive to mumps and rubella, and all but one subject were seropositive to measles. Immunogenicity results for each component antigen were similar for DTPa-IPV and separately co-administered DTPa and IPV. Local reactions were common with 24.0% and 31.1% of children experiencing swelling >50mm at the DTPa-IPV and DTPa injection sites, respectively. The DTPa-IPV combination did not increase the incidence or intensity of adverse events compared with separately administered DTPa+IPV. The response to the concomitantly administered MMR vaccine was similar in the two groups and similar to previously reported responses for a second dose of MMR. This combined DTPa-IPV vaccine has a similar reactogenicity profile to DTPa, is immunogenic when given as a booster dose at 4-6 years of age, and has no impact on the immunogenicity of a co-administered second dose of MMR vaccine.

Safety and immunogenicity of a combined DTPa–IPV vaccine administered as a booster from 4 years of age: A review

A combined DTPa-IPV booster vaccine was administered as a 4th or 5th dose after DTPa or DTPw priming. Over 99% vaccines developed antibody levels considered to be protective to diphtheria, tetanus and poliovirus, and >95% mounted a response to acellular pertussis antigens. Rectal temperature >39.5 degrees C was observed in at most 3.2% of vaccinees. Swelling >50 mm occurred in 24% of DTPa-primed compared to 5.5% of DTPw-primed children. Large swelling involving the entire upper arm (extending to involve the elbow joint) was reported for up to 1.2% of DTPa-primed subjects, which is consistent with literature reports for other DTPa vaccines.

Quantitative real-time RT-PCR--a perspective

The real-time reverse transcription polymerase chain reaction (RT-PCR) uses fluorescent reporter molecules to monitor the production of amplification products during each cycle of the PCR reaction. This combines the nucleic acid amplification and detection steps into one homogeneous assay and obviates the need for gel electrophoresis to detect amplification products. Use of appropriate chemistries and data analysis eliminates the need for Southern blotting or DNA sequencing for amplicon identification. Its simplicity, specificity and sensitivity, together with its potential for high throughput and the ongoing introduction of new chemistries, more reliable instrumentation and improved protocols, has made real-time RT-PCR the benchmark technology for the detection and/or comparison of RNA levels.

An Anopheles gambiae salivary gland promoter analysis in Drosophila melanogaster and Anopheles stephensi

Regulatory regions driving gene expression in specific target organs of the African malaria vector Anopheles gambiae are of critical relevance for studies on Plasmodium-Anopheles interactions as well as to devise strategies for blocking malaria parasite development in the mosquito. In order to identify an appropriate salivary gland promoter we analysed the transactivation properties of genomic fragments located just upstream of the An. gambiae female salivary gland-specific genes AgApy and D7r4. An 800 bp fragment from the AgApy gene directed specific expression of the LacZ reporter gene in the salivary glands of transgenic Anopheles stephensi. However, expression levels were lower than expected and the transgene was expressed in the proximal-rather than in the distal-lateral lobes of female glands. Surprisingly, a promoter fragment from the D7r4 gene conferred strong tissue-specific expression in Drosophila melanogaster but only low transcription levels in transgenic An. stephensi. These results imply a certain conservation of gland-specific control elements between the fruit fly and the mosquito suggesting that an increased degree of complexity, probably connected to the evolution of haematophagy, underlies the regulation of tissue-specific expression in mosquito female salivary glands.

Gestational profile of Na+/H+ exchanger and Cl−/HCO3− anion exchanger mRNA expression in placenta using real-time QPCR

The onset of maternal blood flow (10-12 weeks gestation) results in increased oxygenation of the placenta. We investigated whether the expressions of Na+/H+ exchanger (NHE) and Cl-/HCO3- anion exchanger (AE), thought to have an important role in maintaining intracellular pH of the syncytiotrophoblast and fetal pH homeostasis, are altered at the same time as this increase in blood flow. Real-time quantitative PCR was used to examine steady state levels of NHE (NHE1, 2, 3) and AE (AE1, 2) mRNA expression in early (6-9 weeks) and late (10-13 weeks) first trimester and full-term (38-40 weeks) placentas. beta-Actin, IF2B and GAPDH mRNA was also measured. None of the genes showed a significant difference in expression between the early and late first trimester groups. However, NHE2 (p < 0.001) and GAPDH (p < 0.05) mRNA expression significantly increased 18- and 3.7-fold between early first trimester and term. In conclusion, this study provides additional evidence that GAPDH is an unsuitable housekeeping gene for normalization of transcript levels in placenta. The expression of NHE and AE in the villous placenta is not altered concomitant with the onset of maternal blood flow. However, NHE2 transcripts appear to be gestationally regulated, which may contribute to changes in NHE activity.

Antibody persistence, PRP-specific immune memory, and booster responses in infants immunised with a combination DTPa?HBV?IPV/Hib vaccine

A new single-injection combination vaccine against six diseases has been developed to accommodate the growing number of recommended paediatric vaccines. A pentavalent liquid diphtheria, tetanus, acellular pertussis (3-component), hepatitis B, and inactivated polio (types 1-3) combined vaccine (DTPa-HBV-IPV) is extemporaneously mixed with a lyophilized Haemophilus influenza type B (Hib) conjugate vaccine (polyribosyl-ribitol phosphate (PRP)-T) and given as a single-injection. A cohort of 368 healthy infants was initially studied to evaluate the immunogenicity and reactogenicity of this hexavalent combination given as a primary course at 2, 4, and 6 months of age. At 15 months of age, from this cohort, 219 children received a booster dose of a licensed DTPa/Hib (PRP-T) vaccine to assess the booster response, while 70 received a challenge dose of unconjugated PRP (PRP) vaccine (to evaluate Hib-specific memory) plus a separate DTPa vaccine. Seven to 10 days following plain PRP challenge, anti-PRP geometric mean antibody concentrations (GMCs) had increased 13-fold to 5.67 microg/ml, and thirty days after conjugated PRP booster vaccination, anti-PRP antibody GMCs increased 102-fold. Both responses are indicative of immune memory. Vaccination was well tolerated following all primary and booster doses, although 10.5% of booster recipients experienced >50-mm local swelling at the site of DTPa vaccination. We conclude that DTPa-HBV-IPV/Hib is safe and immunogenic for primary vaccination, and that Hib-specific memory is induced by primary vaccination.

Hyperbaric oxygen as an adjunct in zygomycosis: randomized controlled trial in a murine model

Zygomycosis was induced by injecting CD-1 mice with 5 mg of intraperitoneal deferoxamine and then 10(6) CFU of intravenous and intrasinus Rhizopus arrhizus. The addition of hyperbaric oxygen (2.0 atm absolute twice daily) to amphotericin B did not improve survival over that achieved with amphotericin B and placebo air treatments.

Risk-factors for meningococcal disease in Victoria, Australia, in 1997

In Victoria between 1990 and 1996, meningococcal infections occurred in 1-2/100,000 people each year, with sometimes devastating outcome. In 1997, a typical year, we conducted a case-control study of all cases notified to the State Disease Control Unit, to investigate personal, environmental and lifestyle risk factors. In bivariate analysis many exposures were statistically significantly different (at P = 0.01) in cases and controls. The level of risk, and specific risks, differed between children (under 16) and adults (16 years and over). In multivariate analysis few exposures remained significant (at P = 0.05). However, these included having a smoker amongst close contacts, exposure to construction dust, recent illness, a history of snoring and speech problems, and sharing a bedroom. Besides confirming some previously identified risk factors, this is the first time that snoring and speech problems have been identified as risk factors for meningococcal disease.

Hypercapnia related to a faulty adult co-axial breathing circuit

IMPLICATIONS

This report describes the appearance of CO2 on the capnograph during inspiration, which was linked to disconnection of the inner tube of a coaxial circuit extension piece. The increased use of coaxial breathing systems for adults makes inner tubes disconnections an important consideration when the CO2 appears during inspiration.

Laboratory enhanced surveillance for meningococcal disease in Victoria

OBJECTIVE

To describe the epidemiological and microbiological characteristics and notification patterns of invasive meningococcal disease (IMD) in Victoria between 1990 and 1999.

METHODS

Cases of IMD occurring between 1990 and 1995 identified in any of three databases were combined, matching where possible. Statistical modelling provided estimates of cases missing from all datasets. Notification sources for 1999 and 2000 cases were identified. Cases identified from notification and laboratory results provided the data to describe IMD epidemiology between 1990 and 1999.

RESULTS

Between 1990 and 1995, 479 cases of IMD were identified. Three individual datasets each identified between 62 and 82% of cases and 47% of cases were identified in all three datasets. Statistical modelling estimated that between 37 and 83 additional cases were not identified by any dataset. Serogroup B and C strains caused 63 and 33% of culture-positive cases, respectively, with a substantial rise in serogroup C cases in 1999. Epidemiological characteristics remained relatively constant between 1990 and 1998, but an increase in patient age was seen in cases with serogroup C disease in 1999. In addition to three clonal strains seen elsewhere, an additional strain was identified that was unique to Victoria. Since January 1999, only 72% of notifications have come from treating doctors.

CONCLUSIONS

Meningococcal disease is of increasing public health significance in Victoria. Laboratory enhanced notification has improved case identification and detailed microbiological information has improved our understanding of the changing epidemiology of this disease. Collaboration with laboratories and other agencies, active investigation of putative cases and microbiological monitoring are important elements in supporting public health decisions about the control of IMD.

Adolescent hepatitis B immunisation--should it be the law?

Universal hepatitis B immunisation of young adolescents was included in the Australian Standard Vaccination Schedule in 1998. However, rates of immunisation among adolescents world-wide have often been inadequate. Australia's experience in this area is no exception, particularly in States where school-based delivery is not carried out. Legislation for pre-school immunisation certification currently exists in several States and this legislation is distinctly different from the compulsory or mandatory immunisation that exists in several other developed countries. There have been demonstrable gains in uptake as a result of mandatory immunisation requirements in the United States and there is evidence to suggest that immunisation certification in Australia has also been beneficial. However, it is important to recognise that both certification and mandatory immunisation legislation have inherent difficulties. In this paper, we argue that legislation for high school immunisation certification, as part of a multi-faceted vaccine delivery strategy tailored to adolescents, is required to achieve the uptake that will lead to interruption of transmission of the hepatitis B virus in Australia. Not only will it substantially reduce incident cases of hepatitis B for the next decade, it will also provide a framework for the successful introduction of future adolescent vaccine initiatives in Australia.

Respiratory distress syndrome and birth order in premature twins

OBJECTIVE

To determine the effect of birth order on respiratory distress syndrome (RDS) in the outcome of twins in a large premature population managed in a modern neonatal intensive care unit.

METHODS

An historical cohort study design was used to analyse the neonatal outcomes of 301 premature liveborn twin sibling pairs of between 23 and 31 weeks gestation from the Australia and New Zealand Neonatal Network 1995 database.

RESULTS

Among the 56 twin sibling pairs who were discordant for RDS, the second twin was affected in 41 cases (odds ratio (OR) 2.7, 95% confidence interval (CI) 1.5 to 5.3). The excess risk of RDS in the second twin increased with gestation and was statistically significant for twins above 29 weeks gestation (OR 4.4, 95% CI 1.6 to 15).

CONCLUSIONS

There is a significant increased risk of RDS associated with being the second born of premature twins, which appears to depend on gestation.

A combined liquid Hib (PRP-OMPC), hepatitis B, diphtheria, tetanus and whole-cell pertussis vaccine: controlled studies of immunogenicity and reactogenicity

We evaluated the immunogenicity and reactogenicity of a new liquid pentavalent combination vaccine, which incorporates a diphtheria, tetanus and whole-cell pertussis vaccine (DTP) with Hib (PRP-OMPC) and hepatitis B vaccine (HB), in a series of three studies involving 2156 infants. The vaccination schedule was 2, 4, 6 and 18 months for all studies. In addition, subjects in the third study also received a dose of monovalent hepatitis B vaccine at birth. The principal study was a randomised double blind trial of two separate, but concurrently administered vaccines in each of three groups: pentavalent vaccine [DTP-Hib-HB] plus placebo (Group A, n=619); quadrivalent vaccine [DTP-HB] plus Hib vaccine (Group B, n=620); and bivalent vaccine [Hib-HB] plus DTP (Group C, n=226). The second study (Group D, n=231) was an open trial of three separate, but concurrently administered licensed control vaccines (DTP, Hib and HB). The third study (Group E, n=460) administered a dose of monovalent hepatitis B vaccine at birth followed by pentavalent vaccine as for Group A. Subjects were bled prior to the 2- and 18-month vaccinations, and a month after the 6- and 18-month vaccinations. A diary card was used to record subject temperatures and other systemic and local clinical signs for 7 days after each vaccination. The pentavalent vaccine, whether or not preceded by a birth dose of hepatitis B vaccine, was generally well tolerated at all administration times, and had a reactogenicity profile similar to that observed for licensed vaccine controls. Diphtheria and tetanus antibody levels were substantially above protective levels in all study groups. The anti-HBs responses (% > or = 10 mIU/ml) following the 6-month dose of vaccines were, respectively, for Groups A-E: 83.2, 91.7, 96.5, 98.8 and 93.9%, and following the 18-month doses: 87.9, 97.5, 98.8, 98.8 and 92.8%. Anti-PRP responses (% > or = 1.0 microg/ml) following the 6-month dose for Groups A-D were 86.0, 90.5, 91.2, and 74.4%, and after the 18-month dose for Groups A-E were 97.3, 98.3, 98.1, 97.0, and 99.5%. Consistently higher geometric mean titres (GMTs) for pertussis antibodies to agglutinogens (Agg2, Agg3) and pertactin were recorded for the pentavalent vaccine compared to the licensed control vaccine, though they were somewhat lower for pertussigen (PT). Except for the hepatitis B response, antibody responses induced by the pentavalent vaccine to all antigens with a schedule commencing at 2 months of age and completed at 18 months were equivalent to responses to the same antigens induced by the separate, but concurrently administered licensed control vaccines. A regimen of a birth dose of hepatitis B vaccine followed by pentavalent vaccine at 2, 4, 6 and 18 months was not countered by any clinically significant decrease in seroresponses.

Quality of hospital care for seriously ill children in less-developed countries

BACKGROUND

Improving the quality of care for sick children referred to hospitals in less-developed countries may lead to better outcomes, including reduced mortality. Data are lacking, however, on the quality of priority screening (triage), emergency care, diagnosis, and inpatient treatment in these hospitals, and on aspects of these potential targets that would benefit most from interventions leading to improved health outcomes.

METHODS

We did a qualitative study in 13 district hospitals and eight teaching hospitals in seven less-developed countries. Experienced paediatricians used a structured survey instrument to assess initial triage, emergency and inpatient care, staff knowledge and practices, and hospital support services.

FINDINGS

Overall quality of care differed between countries and among hospitals and was generally better in teaching hospitals. 14 of 21 hospitals lacked an adequate system for triage. Initial patient assessment was often inadequate and treatment delayed. Most emergency treatment areas were poorly organised and lacked essential supplies; families were routinely required to buy emergency drugs before they could be given. Adverse factors in case management, including inadequate assessment, inappropriate treatment, and inadequate monitoring occurred in 76% of inpatient children. Most doctors in district hospitals, and nurses and medical assistants in teaching and district hospitals, had inadequate knowledge and reported practice for managing important childhood illnesses.

INTERPRETATION

Strengthening care for sick children referred to hospital should focus on achievable objectives with the greatest potential benefit for health outcome. Possible targets for improvement include initial triage, emergency care, assessment, inpatient treatment, and monitoring. Priority targets for individual hospitals may be determined by assessing each hospital.

Continuous quality improvement for patients with back pain

Recent evidence has changed traditional approaches to low back pain, suggesting minimal bed rest, highly selective imaging, and early return to normal activities. However, there are wide geographical variations in care, and substantial gaps between practice and evidence. This project sought to merge scientific evidence about back pain and knowledge about behavior change to help organizations improve care for back pain. Participating insurance plans, HMOs, and group practices focused on problems they themselves identified. The year-long program included quarterly meetings, coaching for rapid cycles of change, a menu of potential interventions, and recommendations for monitoring outcomes. Participants interacted through meetings, e-mail, and conference calls. Of the 22 participating organizations, 6 (27%) made major progress. Typical changes were reduced imaging, bed rest, and work loss, and increased patient education and satisfaction. Specific examples were a 30% decrease in plain x-rays, a 100% increase in use of patient education materials, and an 81% drop in prescribed bed rest. Despite the complexity of care for back pain, rapid improvements appear feasible. Several organizations had major improvements, and most experienced at least modest improvements. Key elements of successful programs included focus on a small number of clinical goals, frequent measurement of outcomes among small samples of patients, vigilance in maintaining gains; involvement of office staffs as well as physicians, and changes in standard protocols for imaging, physical therapy, and referral.

Growth of the genital primordium as a marker to describe a time course for the heterogonic larval development in Strongyloides stercoralis

A time course for the heterogonic development of Strongyloides stercoralis is described and a method for distinguishing the early larval stages of this nematode is proposed. The number of cells in the developing gonad were counted at various time intervals of incubation, along with the percentage of larvae in molt at each interval. The time course of growth of the gonad follows a pattern comparable to that reported for body length in an idealized general nematode. A model for the heterogonic development of S. stercoralis is proposed, which, although similar to other nematode developmental models, is stage specific for S. stercoralis, allowing the otherwise morphologically similar rhabditiform stages (L1, L2) to be distinguished.

Twelve year outcomes following bacterial meningitis: further evidence for persisting effects

AIM

To determine whether intellectual and cognitive impairments observed seven years following early childhood bacterial meningitis persist into adolescence.

METHODS

Blinded neuropsychological, auditory, and behaviour assessments were conducted in 109 (69%) subjects from an original cohort of 158 children, seven and 12 years after their meningitis, and in 96 controls.

RESULTS

Meningitis subjects remained at greater risk than controls for any disability (odds ratio OR 4.7, confidence interval 2.2 to 9.6). Those with acute neurological complications had more sequelae than children with uncomplicated meningitis or controls (47% v 30% v 11.5% respectively; p < 0.001). Differences in intellectual, academic, and high level cognitive function between subjects and controls were maintained at the seven and 12 year assessments. In contrast, lower order skills improved, while behaviour scores deteriorated significantly (p = 0.033).

CONCLUSIONS

Many of the deficits identified at the seven year follow up persist 12 years after an episode of bacterial meningitis.