Using Innovation to Address Adolescent and Young Adult Health Disparities in Pelvic Inflammatory Disease: Design of the Technology Enhanced Community Health Precision Nursing (TECH-PN) Trial

New approaches to pelvic inflammatory disease (PID) care among adolescents and young adults (AYAs) that optimize self-care and personalize treatment are warranted to address age and racial-ethnic PID-related health disparities. Here we describe the 13-month preliminary feasibility and acceptability outcomes of recruitment, retention, and intervention delivery for Technology Enhanced Community Health Precision Nursing (TECH-PN) randomized controlled trial. Urban AYAs 13-25 years assigned female sex at birth with acute mild-moderate PID provided baseline and follow-up interview data and vaginal specimens for sexually transmitted infection (STI), cytokine, and microbiota assessment. All participants received medications and text-messaging support. Participants were block randomized to either control or intervention. Control participants received 1 community nursing visit with self-management for interim care per national guidelines. Intervention participants received unlimited precision care services driven by interim STI and macrolide resistance testing results by an advanced practice provider. In the first 13 months, 75.2% patients were eligible, and 76.1% of eligible patients enrolled. Of the participants, 94% completed the intervention and 96%, 91%, and 89%, respectively, completed their 14-, 30-, and 90-day visits. Baseline laboratory results revealed infection rates that were highest for Mycoplasma genitalium (45%) followed by Chlamydia trachomatis (31%). Preliminary enrollment, STI, intervention delivery, and retention data demonstrate the feasibility and acceptability of the TECH-PN intervention and support rationale for precision care for PID among urban AYAs. ClinicalTrials.gov Identifier. NCT03828994.

Dyadic Intervention for Sexually Transmitted Infection Prevention in Urban Adolescents and Young Adults (The SEXPERIENCE Study): Protocol for a Randomized Controlled Trial (Preprint)

Background

Adolescents and young adults (AYA) aged younger than 25 years have the highest rates of sexually transmitted infections (STIs) in the United States. Current STI prevention strategies for AYA rely primarily on individual approaches, leaving sexual partners with significant unmet sexual and reproductive health care and health education needs. Dyadic interventions may hold promise for harnessing the power of communal coping within relationship dynamics to enhance sexual decision making, communication, and behavior changes that reduce the future risk of STIs.

Objective

This paper describes the protocol and research methods of a dyad-based behavioral intervention that augments individual evidence-based interventions with joint health education counseling for heterosexual AYA dyads within a primary care setting. The trial aims to improve partner communication and collaborative sexual decision making and promote the adoption of sexual behaviors such as consistent condom use. The primary objective of this study is to assess the feasibility, acceptability, and effectiveness of a dyadic intervention targeted at preventing STIs in heterosexual couples in an urban setting.

Methods

A total of 100 AYA (50 dyads) aged 16 to 25 years, engaged in heterosexual intercourse, who reside in the city and are willing to recruit their main sexual partner for the study will be recruited and randomized into 2 groups, an intervention arm and a control arm. Participants will be recruited from an AYA medicine clinic and by using social media (Facebook and Instagram). The index participant and partner will complete a single individual session separately (Sister to Sister or Focus on the Future) with a gender-matched health educator. Dyads will then be randomized to receive an additional joint debriefing session together to discuss relationship dynamics, condom negotiation, etc. Participants will separately complete a telephone interview 6 weeks postintervention to determine the feasibility, acceptability, and impact of the intervention on mutual sexual negotiation, consistency of condom use, and communal coping skills, etc.

Results

So far, 25.4% (44/173) of eligible participants have been enrolled and randomized. Participants are mostly female (20/22, 91%), with at least a high school diploma (19/22, 86%), and 9 average lifetime sexual partners. Acceptability is high, with 98% (43/44) of participants expressing satisfaction with their study experience; 100% of dyads recruited were still together at 6-week follow-up.

Conclusions

Findings from this study will add to the current literature on the approaches to STI prevention, and its success will inform its application in risk reduction counseling for youth who are most at risk.

Trial Registration

Clinical Trials.gov NCT03275168; https://www.clinicaltrials.gov/ct2/history/NCT03275168

International Registered Report Identifier (IRRID)

DERR1-10.2196/29389

Recruitment of Youth Living With HIV to Optimize Adherence and Virologic Suppression: Testing the Design of Technology-Based Community Health Nursing to Improve Antiretroviral Therapy (ART) Clinical Trials

Background

Despite advances in HIV diagnosis and treatment, adolescents and young adults 12-25 years old have high HIV incidence, poor engagement and retention in treatment, and low rates of adherence and virologic suppression when compared to their older counterparts. HIV has emerged as a chronic disease for which antiretroviral therapy (ART) adherence is critical for virologic suppression and long-term survival. Virologic suppression has been elusive for many youth with HIV (YHIV). Novel strategies designed to facilitate health care systems’ support for YHIV between medical visits are essential for improving ART adherence, virologic suppression, and long-term survival.

Objective

The aim of this study is to compare the effectiveness of a technology-enhanced community health nursing intervention (TECH2CHECK) to a standard of care (SOC) control group for improving ART adherence and subsequent viral suppression using a randomized trial design. The objectives are to assess the feasibility, acceptability, and cost-effectiveness of TECH2CHECK as compared to SOC for management of HIV in the outpatient setting and to examine the sustainability of self-care behavior, adherence, and virologic suppression among youth following the intervention period.

Methods

We will recruit 120 adherence-challenged YHIV being followed at clinics specializing in HIV care in the Baltimore-Washington metropolitan area and in Jacksonville. Eligible participants complete an audio, computer-assisted self-interview and are randomized to either TECH2CHECK intervention or the SOC (60 participants in each arm). The primary outcome of interest is virologic suppression (viral load <20 copies/mL) and improved treatment adherence. Participants in the intervention arm receive community health nursing visits at 2 weeks, 6 weeks, 10 weeks, 14 weeks, and 26 weeks. The intervention arm also receives SMS messaging comprising daily adherence and appointment reminders and positive reinforcement for medication adherence daily for 2 weeks, on alternate days for 2 weeks, thrice weekly for 1 month, weekly for 3 months, and every 2 weeks for the rest of the study duration. The control group receives appointment reminders and SOC per clinic protocol. Exploratory analysis will be conducted to determine differences in medication adherence and virologic suppression in the 2 arms and to assess cost-effectiveness and study feasibility and acceptability.

Results

In the first 23 months of the study (July 2018-April 2020), 56 (55%) of 102 eligible patients were enrolled and randomized. At present, participating youths are primarily African American (53/56, 95%), male (37/56, 66%), and ≥18 years old (53/56, 95%). Follow-up study visits, as required per the protocol, have been completed by 77% (43/56), 94% (45/48), 95% (37/39), 96% (24/25), and 100% (10/10) of participants at the 1-month, 3-month, 6-month, 12-month, and 18-month follow-ups, respectively.

Conclusions

Preliminary accrual and retention data suggest that TECH2CHECK is feasible and acceptable.

Trial Registration

ClinicalTrials.gov NCT03600103 https://clinicaltrials.gov/ct2/show/NCT03600103

International Registered Report Identifier (IRRID)

DERR1-10.2196/23480

Clearance of Mycoplasma genitalium and Trichomonas vaginalis Among Adolescents and Young Adults With Pelvic Inflammatory Disease: Results From the Tech-N Study

Current pelvic inflammatory disease (PID) treatment effectively treats Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT). However, coverage may be inadequate for Mycoplasma genitalium (MG)/Trichomonas vaginalis (TV) infections. We compared the longitudinal MG and TV outcomes with NG/CT outcomes for women enrolled in a longitudinal randomized controlled trial to optimize outcomes after PID. The prevalences of CT and NG were lower at 30- and 90-day follow-up compared with the prevalence at the time of diagnosis. No significant difference was observed for MG (odds ratio, 0.95; 0.86-1.04; P = 0.265) and TV (odds ratio, 0.89; 0.75-1.04; P = 0.146) over time for both treatment groups, showing that persistence and/or reinfection with MG and TV occurs more frequently than with CT or NG after treatment of PID using current national treatment guidelines.

Baseline parameters for rotational thromboelastometry in healthy labouring women: a prospective observational study

OBJECTIVE

The aim of this study was to establish rotational thromboelastometry (ROTEM^® ) baseline parameters in labouring women at term gestation. The secondary aim was to compare these reference ranges with those from previous studies on labouring women and from the manufacturer.

DESIGN

A prospective, observational study.

SETTING

Tertiary referral hospital.

PARTICIPANTS

Healthy women in labour.

METHODS

Ethics approval was granted for an opt-out recruitment approach. ROTEM^® testing was performed in labouring women at term gestation. Women with any condition affecting coagulation were excluded. ROTEM^® Delta reference ranges were derived by calculating the 2.5% and 97.5% centiles for INTEM/EXTEM/FIBTEM parameters including amplitude at 5 minutes (A5), coagulation time (CT) and maximum clot firmness (MCF).

MAIN OUTCOME MEASURES

ROTEM^® parameters were measured in labouring women before delivery. The following tests were performed: FIBTEM, EXTEM and INTEM.

RESULTS

One hundred and twenty-one women met the inclusion criteria, with a mean (± SD) age of 29.6 ± 5.4 years and median (interquartile range) gestation of 39.4 weeks (37.4-40.4 weeks). Seventy-five (62.0%) women were nulliparous and 71 (58.7%) delivered vaginally. The median and interquartile ranges for selected ROTEM^® parameters were: FIBTEM A5, 21 mm (IQR 18-23 mm); EXTEM A5, 55 mm (52-58 mm); and EXTEM CT, 52 seconds (48-56 seconds).

CONCLUSIONS

The FIBTEM/EXTEM/INTEM amplitudes were higher than the manufacturer's reference ranges for non-obstetric patients. The FIBTEM MCF upper and lower limits were higher and the EXTEM/INTEM CT was shorter and narrower in range. This study provides reference ranges for ROTEM^® values in healthy labouring women at term gestation with uncomplicated pregnancies.

TWEETABLE ABSTRACT

This is the first study to report on ROTEM^® reference ranges with over 120 healthy labouring women of normal weight at term gestation.

Baseline parameters for rotational thromboelastometry (ROTEM®) in healthy pregnant Australian women: a comparison of labouring and non-labouring women at term

BACKGROUND

Rotational thromboelastometry (ROTEM®) is a point-of-care coagulation test. Reference ranges in non-labouring women have recently been established from a cohort of women presenting for elective caesarean delivery using the recommended minimum sample size of 120. This study aimed to present baseline parameters for labouring and non-labouring women and to compare the mean values of these ROTEM® parameters.

METHODS

Ethical approval was granted for an opt-out recruitment approach for labouring women and written consent was obtained from non-labouring women (data published previously). ROTEM® testing was performed in these two cohorts at term gestation. Women with any condition affecting coagulation were excluded. ROTEM® Delta reference ranges were derived by calculating the 2.5 and 97.5 percentiles for INTEM/EXTEM/FIBTEM amplitude at 5 min (A5), coagulation time (CT), maximum clot firmness (MCF) and clot formation time (CFT).

RESULTS

One hundred and twenty-one labouring and 132 non-labouring women met inclusion criteria. The mean values for selected ROTEM® parameters for labouring and non-labouring women respectively were: FIBTEM A5, 21.05 and 19.7 mm (P=0.008); EXTEM A5, 54.8 and 53.2 mm (P=0.025); and EXTEM CT, 52.2 and 53.7 s (P=0.049). Significant differences between the groups were observed in measures of clotting onset and clot firmness.

CONCLUSIONS

We demonstrated a significant decrease in the mean time-to-clotting onset in labouring women compared with non-labouring women. Mean values for measures of clot firmness were greater in labouring women. In comparison to previously established ROTEM® baseline parameters for non-labouring women, this study provides evidence that there is greater hyper-coagulability in labouring women.

Efficacy of a Technology-Enhanced Community Health Nursing Intervention vs Standard of Care for Female Adolescents and Young Adults With Pelvic Inflammatory Disease: A Randomized Clinical Trial

IMPORTANCE

Pelvic inflammatory disease (PID) is a common reproductive health disorder that disproportionately affects female adolescents and young adults. Despite data indicating poor adherence and adverse outcomes among those who experience subsequent Neisseria gonorrhoeae and Chlamydia trachomatis infection, few trials have been designed to address this public health need.

OBJECTIVE

To examine the efficacy of a technology-enhanced community health nursing (TECH-N) intervention vs standard of care for improving PID self-management behaviors and 90-day longitudinal prevalence of N gonorrhoeae and C trachomatis infection.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial of the TECH-N intervention was conducted among female patients 13 to 25 years of age diagnosed with mild to moderate PID who were being discharged to outpatient treatment from September 6, 2012, to December 8, 2016, at a large academic medical center. The final analysis of data was completed in November 2018. This study compared the efficacy of the intervention with that of the standard of care using an intention-to-treat analysis.

INTERVENTIONS

Enrolled participants completed an audio computer-assisted self-interview, provided specimens for N gonorrhoeae and C trachomatis testing, and were randomized to standard treatment (n = 137) or the TECH-N intervention (n = 149). Intervention participants received text-messaging support and a community health nurse visit within 5 days of diagnosis. Change in the prevalence of N gonorrhoeae and C trachomatis infection was estimated with logistic regression. The N gonorrhoeae and C trachomatis positivity rate over time was evaluated using generalized estimating equations.

MAIN OUTCOMES AND MEASURES

The primary outcome was the prevalence of N gonorrhoeae and C trachomatis infection at 90-day follow-up. The secondary outcome was adherence to the Centers for Disease Control and Prevention recommendations for self-care.

RESULTS

A total of 286 patients (mean [SD] age, 18.8 [2.5] years; 268 [93.7%] African American) participated in the study. Although the study groups were demographically similar, the intervention group had a higher baseline rate of C trachomatis infection (45 of 139 [32.4%] vs 25 of 132 [18.9%], P = .01). Although N gonorrhoeae and C trachomatis positivity was not statistically different between groups at 90-day follow-up (6 of 135 [4.4%] vs 13 of 125 [10.4%], P = .07), the differential rate of decrease was significantly higher in the intervention group (48 of 140 [34.4%] to 6 of 135 [4.4%] compared with 34 of 133 [25.6%] to 13 of 112 [10.4%], P = .02). Intervention participants were more likely to receive the Centers for Disease Control and Prevention-recommended short-term follow-up visit compared with the control group (131 of 139 [94.2%] vs 20 of 123 [16.3%], P < .001).

CONCLUSIONS AND RELEVANCE

Adolescent and young adults with PID in the TECH-N intervention were more likely to experience decreases in N gonorrhoeae and C trachomatis positivity compared with the control group and to receive short-term clinical assessment. These findings suggest that the TECH-N intervention should be considered as a potential enhancement of standard of care approaches for management of female adolescents and young adults with mild to moderate PID in urban communities facing significant sexually transmitted infection disparities.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01640379.

Australian multicentre study of current real-world prophylaxis practice in severe and moderate haemophilia A and B

INTRODUCTION

With the emergence of novel treatment products for haemophilia and an increasing focus on the benefits of pharmacokinetic driven individualized prophylaxis, robust national data with regard to current patterns of factor consumption and adherence are required.

AIM

To characterize current Australian practice with regard to use of prophylactic clotting factor infusions in patients with moderate or severe haemophilia A (HA) and haemophilia B (HB).

METHODS

This was a retrospective, non-interventional study utilizing Australian Bleeding Disorder Registry (ABDR) data collected over a 12 month period. Registered and consented patients with moderate or severe HA or HB without inhibitors were included.

RESULTS

A total of 718 HA (551 severe, 167 moderate) and 166 HB (87 severe, 79 moderate) patients were included. Regular prophylaxis was prescribed in 453 patients (82%) with severe HA, 42 patients (25%) with moderate HA, 66 patients (75%) with severe HB and 11 patients (14%) with moderate HB. Near universal prophylaxis was achieved in the paediatric subgroup. The mean weekly dose of factor VIII in severe HA was 84 international units/kg/wk (IU/kg/wk) vs 71 IU/kg/wk of factor IX in severe HB. Most patients on prophylaxis were treated ≥3 times/wk (HA) or 2 times/wk (HB). Non-adherence peaked in the 20-29 year age group. Older individuals on regular prophylaxis used more factor than was expected for their prescribed regimen.

CONCLUSION

Prophylaxis rates in severe haemophilia are comparable with other developed nations. The benefit of a national registry is demonstrable. Furthermore research into the underlying reasons for non-compliance in young adults with haemophilia is required.

Challenges in hemophilia care in Australia and New Zealand

BACKGROUND

Health and life expectancy for people with hemophilia have improved significantly in recent years, but we face new challenges, especially in the context of resource-constrained health services.

AIM

This paper aims to highlight such challenges and propose practical solutions.

METHODS

Nine hemophilia specialists from Australia and New Zealand reached consensus on areas of greatest need for improvement in hemophilia care in these countries, based on clinical experience and published data, and agreed on how to address these.

RESULTS

Demography, optimizing treatment and assessing treatment success were identified as broad areas of challenge which included: comorbidities in ageing patients; transitioning from pediatric to adult care; equity of care for remote populations; weight-based dosing in obese patients; tailoring prophylaxis; accurate diagnosis of acute joint pain; managing chronic arthropathy; providing psychosocial support; consistency in definitions and assessment; and quantifiable outcome measures. Practice points included increased cross-specialty coordination and including psychologists and rheumatologists as part of comprehensive care teams; close collaboration between pediatric and adult centers to facilitate transition of care; systems such as telehealth that ensure continuity of care for remote populations; using pharmacokinetic data to tailor therapy; rapid and accurate diagnosis of acute joint pain; using data from bleeding registries to assess treatment effects and help with service planning; and ensuring consistency through benchmarking and standardization of HTCs.

SUMMARY

Achieving treatment equity, optimal outcomes and cost savings may be possible through investing in national governance structures, expanding the comprehensive model of care and implementing innovative solutions tailored to local needs.

Serum apolipoprotein C-III is independently associated with chronic hepatitis C infection and advanced fibrosis

BACKGROUND

The hepatitis C virus (HCV) is known to disrupt lipid metabolism, making serum lipoprotein levels good candidates to explore as markers of HCV disease progression. Assessment of the major apolipoproteins (Apo) and their relationship to hepatic fibrosis remain largely unexplored.

METHODS

We compared the levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), and Apo A-I, -B, -C-III, and -E between patients with cleared versus active infection (n = 83), and between those chronically infected patients (n = 216) with advanced versus mild-moderate hepatic fibrosis (METAVIR stage F3-4 vs. F0-2) using multiple logistic regression.

RESULTS

Apo C-III levels were 25% higher in subjects with cleared infection versus those with active infection (p = 0.009). Low levels of Apo C-III (p = 1.3 × 10(-5)), Apo A-I (p = 2.9 × 10(-5)), total cholesterol (p = 5.0 × 10(-4)), LDL-C (p = 0.005), and HDL-C (p = 2.0 × 10(-4)) were associated with advanced fibrosis in univariate analyses. Multivariable analysis revealed Apo C-III as the most significant factor associated with advanced fibrosis (p = 0.0004), followed by age (p = 0.013) and Apo A-I (p = 0.022). Inclusion of both Apo C-III and Apo A-I in a model to predict advanced fibrosis improved the area under the receiver operator curve only modestly.

CONCLUSIONS

Relative to other lipoproteins, low serum Apo C-III levels are the most strongly associated with chronic versus cleared infection and decline with increasing severity of hepatic fibrosis. Apo C-III deserves further attention as a possible marker of HCV disease progression.

Dissolution of porcine incisor pulps in sodium hypochlorite solutions of varying compositions and concentrations

BACKGROUND

The solubility of dental pulp tissue in sodium hypochlorite has been extensively investigated but results have been inconsistent; due most likely to variations in experimental design, the volume and/or rate of replenishment of the solutions used and the nature of the tissues assessed. Traditionally, the sodium hypochlorite solutions used for endodontic irrigation in Australia have been either Milton or commercial bleach, with Milton being the most common. Recently, a range of Therapeutic Goods Administration (TGA) approved proprietary sodium hypochlorite solutions, which contain surfactant, has become available. Some domestic chlorine bleaches now also contain surfactants. The purpose of this study was to perform new solubility assessments, comparing Milton with new TGA approved products, Hypochlor 1% and Hypochlor 4% forte, and with a domestic bleach containing surfactant (White King).

METHODS

Ten randomly assigned pulp samples of porcine dental pulp of approximately equal dimensions were immersed in the above solutions, as well as representative concentrations of sodium hydroxide. Time to complete dissolution was measured and assessed statistically.

RESULTS

White King 4% showed the shortest dissolution time, closely followed by Hypochlor 4% forte. White King 1% and Hypochlor 1% each took around three times as long to completely dissolve the samples of pulp as their respective 4% concentrations, while Milton took nearly 10 times as long. The sodium hydroxide solutions showed no noticeable dissolution of the pulp samples.

CONCLUSIONS

The composition and content of sodium hypochlorite solutions had a profound effect on the ability of these solutions to dissolve pulp tissue in vitro. Greater concentrations provided more rapid dissolution of tissue. One per cent solutions with added surfactant and which contained higher concentrations of sodium hydroxide were significantly more effective in dissolution of pulp tissue than Milton.

Cooperative activation of transcription by autoimmune regulator AIRE and CBP

Autoimmune regulator (AIRE) is a transcriptional regulator that is believed to control the expression of tissue-specific genes in the thymus. Mutated AIRE is responsible for onset of the hereditary autoimmune disease APECED. AIRE is able to form nuclear bodies (NBs) and interacts with the ubiquitous transcriptional coactivator CBP. In this paper, we show that CBP and AIRE synergistically activate transcription on different promoter reporters whereas AIRE gene mutation R257X, found in APECED patients, interferes with this coactivation effect. Furthermore, the overexpression of AIRE and CBP collaboratively enhance endogenous IFNbeta mRNA expression. The immunohistochemical studies suggest that CBP, depending on the balance of nuclear proteins, is a component of AIRE NBs. We also show that AIRE NBs are devoid of active chromatin and, therefore, not sites of transcription. In addition, we demonstrate by 3D analyses that AIRE and CBP, when colocalizing, are located spatially differently within AIRE NBs. In conclusion, our data suggest that AIRE activates transcription of the target genes, i.e., autoantigens in collaboration with CBP and that this activation occurs outside of AIRE NBs.

Dosing strategy for enoxaparin in patients with renal impairment presenting with acute coronary syndromes

BACKGROUND

Phase III clinical studies have confirmed that enoxaparin is superior to standard heparin in reducing the rate of recurrent ischaemic events in patients with non-ST elevation acute coronary syndromes. Patients with moderate to severe renal impairment were, however, excluded from these studies. Due to the hydrophilic disposition of enoxaparin, accumulation is likely in patients with renal dysfunction, thereby increasing the risk of haemorrhagic complications if standard weight adjusted treatment doses are used. Arbitrary dose reduction has been reported to increase the risk of ischaemic events, presumably due to inadequate enoxaparin concentrations.

AIM

The aims of this study were to investigate the influence of glomerular filtration rate (GFR) on the pharmacokinetics of subcutaneously administered enoxaparin, and to develop a practical dosing algorithm in renal impairment that can easily be used at the bedside.

METHODS

Thirty-eight patients, median age 78 years (range 44-87), mean GFR 32 ml min(-1) (range 16-117) and mean weight 69 kg (range 32-95), presenting with acute coronary syndrome were recruited into the study. Approximately 10 anti-Xa concentrations were taken per patient over their period of therapy. A population pharmacokinetic model was developed using non linear mixed effects modelling techniques, utilizing the software NONMEM. Stochastic simulations were performed to identify the most suitable dosing regimen.

RESULTS

Three hundred and thirteen anti-Xa concentrations were collected. A two compartment, first order input model was identified as the best baseline model. Covariates found to improve model fitting were GFR as a linear function on clearance (CL) and weight as a linear function on the central volume compartment (Vc). The fraction of drug excreted unchanged (Fu) was estimated at 71%. CL and Vc from the final covariate model were estimated as; CL (l h(-1)) = 0.681 per 4.8 l hr(-1) (GFR) + 0.229 Vc (l) = 5.22 per 80 kg (total body weight)

CONCLUSIONS

Clearance of enoxaparin was predictably related to GFR estimated using the Cockroft and Gault equation, with ideal body weight used as the size descriptor. According to our model no dosage adjustment from the standard 1.0 mg kg(-1) 12 hourly is required for the first 48 h of treatment. Maintenance doses thereafter can be calculated using standard proportional adjustments based on Fu equal to 0.71.

Molecular and functional analysis identifies ALK-1 as the predominant cause of pulmonary hypertension related to hereditary haemorrhagic telangiectasia

BACKGROUND

Mutations of the transforming growth factor beta (TGFbeta) receptor components ENDOGLIN and ALK-1 cause the autosomal dominant vascular disorder hereditary haemorrhagic telangiectasia (HHT). Heterozygous mutations of the type II receptor BMPR2 underlie familial primary pulmonary hypertension.

OBJECTIVE

To investigate kindreds presenting with both pulmonary hypertension and HHT.

METHODS

Probands and families were identified by specialist pulmonary hypertension centres in five countries. DNA sequence analysis of ALK-1, ENDOGLIN, and BMPR2 was undertaken. Cellular localisation was investigated by heterologous overexpression of mutant constructs in both BAEC and HeLa cells. The impact of a novel sequence variant was assessed through comparative analysis and computer modelling.

RESULTS

Molecular analysis of 11 probands identified eight missense mutations of ALK-1, one of which was observed in two families. Mutations were located within exons 5 to 10 of the ALK-1 gene. The majority of ALK-1 mutant constructs appeared to be retained within the cell cytoplasm, in the endoplasmic reticulum. A novel GS domain mutation, when overexpressed, reached the cell surface but is predicted to disrupt conformational changes owing to loss of a critical hydrogen bond. Two novel missense mutations were identified in ENDOGLIN.

CONCLUSIONS

The association of pulmonary arterial hypertension and HHT identifies an important disease complication and appears most common among subjects with defects in ALK-1 receptor signalling. Future studies should focus on detailed molecular analysis of the common cellular pathways disrupted by mutations of ALK-1 and BMPR2 that cause inherited pulmonary vascular disease.

Quantification of feto-maternal haemorrhage (FMH) by flow cytometry: anti-fetal haemoglobin labelling potentially underestimates massive FMH in comparison to labelling with anti-D

Many centres now routinely use flow cytometry to quantify feto-maternal haemorrhage (FMH). However, which flow cytometric method is the most accurate in quantifying FMH is currently unknown. An audit of clinical results in which FMH had been estimated by both directly conjugated monoclonal anti-D and anti-fetal haemoglobin (HbF) labelling suggested that the anti-HbF labelling method may underestimate massive FMH in comparison to labelling with anti-D. Subsequent to this audit, 46 samples of adult D-negative blood were spiked with varying amounts of D-positive cord blood (0.05-10% fetal cells per sample), and the number of fetal cells present was quantified by both labelling methods. The percentage of fetal cells detected by anti-D was not significantly different to the estimated percentage of fetal cells added to each sample (P = 0.636). However, anti-HbF labelling significantly underestimated the percentage of fetal cells present (P = 0.0001). In comparison to anti-D, the percentage of fetal cells detected by anti-HbF was also significantly lower (P < 0.0001). The difference in fetal cell detection between anti-D and anti-HbF labelling was only apparent in the spiked samples containing > or =1% fetal cells per sample. In samples containing < or =0.6% fetal cells, no significant difference in the detection of fetal cells between anti-D and anti-HbF labelling was observed (P = 0.11). To allow adequate immunoprophylaxis in D-negative mothers with massive FMH, we recommend that anti-D labelling should be used in the routine flow cytometric estimation of FMH.

Single institution outcomes of treatment of severe aplastic anaemia

BACKGROUND

In severe aplastic anaemia, the treatment of choice for young patients with a human leucocyte antigen-matched sibling is now established as allogeneic bone marrow transplantation (BMT). In older patients and in those without a matched sibling donor, immunosuppressive therapy is the usual first option. 'Alternative' marrow donors are emerging as an option for those without a matched sibling donor.

AIMS

To review 10 years of local experience in treating severe aplastic anaemia with BMT and immunosuppressive therapy with emphasis on long-term outcomes.

METHODS

A retrospective analysis was performed of all patients with severe aplastic anaemia presenting to the Royal Brisbane and Royal Children's Hospitals between 1989 and 1999. Data were abstracted regarding patient demographics, pretreatment characteristics and outcome measures, including response rates, overall survival and long-term complications.

RESULTS

Twenty-seven consecutive patients were identified, 12 treated with immunosuppression alone and 15 with BMT. In these two groups, transfusion independence was attained in 25% and 100%, respectively, with overall survival being 36% and 100%, respectively. Those treated with immunosuppression were significantly older (median 41.5 versus 22 years, P = 0.008). Long-term survivors of either treatment had extremely low morbidity. Three patients carried pregnancies to term post-transplant. Three patients received alternative donor BMT with correspondingly excellent survival.

CONCLUSIONS

Patients treated with allogeneic BMT for severe aplastic anaemia enjoyed extremely good long-term survival and minimal morbidity. Patients treated with immunosuppressive therapy had a poorer outcome reflecting their older age and different usage of therapies over the past decade. Optimal treatment strategies for severe aplastic anaemia remain to be determined.

The D(2) dopamine receptor A(1) allele and opioid dependence: association with heroin use and response to methadone treatment

A total of 95 Caucasian opioid-dependent patients were followed over a one-year period in an outpatient methadone treatment program. The frequency of the TaqI A(1) allele of the D(2) dopamine receptor (DRD2) gene was 19.0% in these patients compared with 4.6% in controls free of past and current alcohol and other drug abuse and free of family history of alcohol and other drug abuse (p = 0.009). Twenty-two of these patients dropped out of the methadone program (Group A), 54 had a successful treatment (Group B), and 19 had a poor treatment (Group C) outcome. The frequency of the A(1) allele was highest in Group C (42.1%), followed by Group A (22.7%) and was lowest in Group B (9.3%). The more than fourfold higher frequency of the A(1) allele in the poor treatment outcome group compared with the successful treatment outcome group was significant (p = 0.00002). Moreover, the average use of heroin (grams/day) during the year prior to study entry was more than twice as great in patients with the A(1)(+) allele (A(1)/A(1) or A(1)/A(2) genotype) than those with the A(1)(-) allele (A(2)/A(2) genotype) (A(1)(+) allele = 0.55 +/- 0. 10, A(1)(-) allele = 0.25 +/- 0.05; p = 0.003). The results indicate that DRD2 variants are predictors of heroin use and subsequent methadone treatment outcome and suggest a pharmacogenetic approach to the treatment of opioid dependence.

Seasonal levels of metabolic hormones and substrates in male and female reindeer (Rangifer tarandus)

Seasonal levels of cortisol, growth hormone (GH), insulin like growth factor 1 (IGF-1), glucose, triiodothyronine (T3), free T3, thyroxine and free fatty acids (FFA) were measured every 3 weeks for 54 weeks in the plasma of five adult bulls, and four barren and five pregnant Alaskan reindeer (Rangifer tarandus) cows. Three consecutive samples were taken from each animal. Cortisol levels exhibited wide seasonal variation (9-45 ng/ml) [corrected] without any peak or difference in levels among groups. Rising levels were detected between the 3 consequent samples. Peak GH levels, detected during January and February, were higher in the non-pregnant group (54 ng/ml) than the pregnant (26 ng ml-1) and the male (27 ng ml-1) groups. Low GH levels (2-10 ng ml-1) were recorded between May and September. IGF-1 reached peak levels (715 ng ml-1) in males in August, in non-pregnant females in September (677 ng ml-1), and in the pregnant females in October (505 ng ml-1). Seasonal minima (404 in males, 172 and 93 in pregnant and non-pregnant groups) were detected in February. Glucose was fairly stable throughout the year (100-200 mg/100 ml). A rising levels were found between the three consecutive samples. Triiodothyronine (T3) (2.16-2.30 ng ml-1) peaked in all three groups during the spring and early summer, and minimal levels (0.61-0.97 ng ml-1) were detected from October to January. Conversely, thyroxine or free T3 did not exhibit seasonal variation. FFA fluctuated widely (97-1076 nmol l-1) throughout the year. Only in pregnant females were concentrations more stable (150-460 nmol l-1). Perhaps, because of ad libitum supply of food in captive reindeer, only T3 and GH exhibited pronounced seasonal fluctuations which could be related to the metabolic changes expected during the annual cycle.

Cross-reactivity to porcine factor VIII of factor VIII inhibitors in patients with haemophilia in Australia and New Zealand

BACKGROUND

Inhibitory antibodies which neutralise factor VIII develop in 10-20% of individuals with inherited haemophilia A and rarely as autoantibodies in normal individuals to cause acquired haemophilia. The antibodies are directed against human factor VIII but cross-react to varying degrees with porcine factor VIII. Porcine factor VIII can be used for treatment in individuals with low cross-reactivity.

AIMS

To determine the cross-reactivity of factor VIII inhibitors between human factor VIII and porcine factor VIII, in a population of patients with inherited and acquired haemophilia A. Also, to determine whether patients with inherited haemophilia and inhibitors have a higher incidence of factor VIII gene inversion in intron 22.

METHODS

Samples and data sheets from 43 patients with inherited and ten with acquired haemophilia were submitted from hospitals in Australia and New Zealand. Inhibitor levels to human and porcine factor VIII were measured by the Bethesda method in 39 with inherited and nine with acquired haemophilia A.

RESULTS

Of 39 patients with inherited haemophilia A, cross-reactivity was 0% in 17 patients, 1-19% in six, 20-39% in 11 and 40-80% in five. In six of nine patients with acquired haemophilia cross-reactivity was < or = 7%. In inherited severe haemophilia A, the frequency of the intron 22 inversion was not greater in 37 study patients than in 28 patients without an inhibitor.

CONCLUSIONS

Many patients in Australia and New Zealand with inhibitors to human factor VIII presently show a low or absent level of cross-reactivity to porcine factor VIII. These may respond to treatment with this concentrate at least in the short term. There remains a group of patients with high cross-reactivity who will respond only to recombinant factor VIIa or prothrombin complex concentrates.

Seasonal levels of reproductive hormones and their relationship to the antler cycle of male and female reindeer (Rangifer tarandus)

Seasonal levels of LH, FSH, testosterone (T), estradiol, progesterone (P), and prolactin (PRL) were determined in the plasma of five adult bulls, and five barren and four pregnant cows of Alaskan reindeer (Rangifer tarandus), which were sampled every 3 weeks for 54 weeks. The male reproductive axis was sequentially activated; LH peaked in May-June (2 ng/ml), FSH in June (51 ng/ml), and T in September (11.8 ng/ml). LH levels in females reached a maximum in both groups at the end of August (the beginning of the rut). Seasonal variation in FSH was minimal in pregnant cows, but exhibited one elevation (41 ng/ml) in barren ones in November. T levels in cows remained at barely detectable levels. The decrease of T values observed in both groups in December and March was not significant. PRL peaked in May in cows (135 ng/ml pregnant, 140 ng/ml non-pregnant) and in June in bulls (92 ng/ml). Estradiol was highest in bulls in the rut (August), in non-pregnant cows in January and in pregnant cows in April, shortly before parturition. P levels in the pregnant cows rose from September and peaked (9 ng/ml) shortly before parturition in April. In the non-pregnant females P values increased and decreased several times before peaking (5 ng/ml) in March. In the males, the variation of T and estradiol levels correlated relatively well with the antler cycle but in the females the variation of neither estradiol, progesterone nor T appeared to be related to mineralization or casting of antlers.

Experience with recombinant factor VIIa in Australia and New Zealand

Recombinant factor VIIa (rFVIIa; NovoSeventrademark) was availablefor compassionate use in Australia and New Zealand from 1991 to 1994. Over this period there were 18 treatment episodes in 9 patients, age 8-66 years, with haemophilia A and high titre inhibitors cross-reacting with porcine factor VIII. There were no significant adverse effects. Treatment with rFVIIa resulted in a successful outcome in 8 potentially life-threatening (retroperitoneal, subdural, gastro-intestinal) bleeds. Elective cystoscopy, repair of a cranial flap, yttrium synovectomy and inguinal herniotomy were performed successfully, as was surgical decompression of a flexor pollicis longus bleed. Treatment of a patient with an infected haematoma had limited success, attributed to intermittent suboptimal doses. In 2 patients, satisfactory haemostasis was achieved for multiple dental extractions; subsequent oozing was attributed to suboptimal rFVIIa and/or antifibrinolytic therapy.

Allogeneic BMT from a donor with fragile X syndrome: cytogenetic and molecular evaluation

We report the first case of engraftment of bone marrow collected from a donor with Fragile X syndrome with subsequent cytogenetic and molecular evaluation. Engraftment was prompt and stable. Whilst the Fragile X abnormality could be detected initially by molecular techniques in the peripheral blood, it could not be detected cytogenetically while the patient was receiving CsA.

Ultrasonography of masseter muscle size in normal young adults

The present study was planned to determine the relationship between linear dimensions of human masseter muscle cross-section and cross-sectional area (CSA), and to assess symmetry between the two sides in normal young adults. Cross-sectional images of the masseter muscle were measured bilaterally by real-time ultrasound imaging in 39 healthy dentate subjects, 19 males and 20 females, aged 21-47. From stored images, CSA and two linear measurements of muscle cross-section were obtained (the shortest and the longest distance through the muscle group). Correlation and regression analyses were performed to examine the relationship between CSA and the linear dimensions (both individually and with the linear dimensions multiplied). Symmetry of CSA between the two sides of the face was examined using the paired t-test. The significance of correlation coefficients (r) and the difference between the slopes of the regression lines were also examined. Masseter CSA was larger in males than in females. All correlation values between CSA and linear measurements were significant but muscle CSA was most accurately predicted when the linear measurements were multiplied (r = 0.97; P < 0.001). Although the correlation in this regard was high, the linear dimensions consistently overestimated the actual CSA by approximately 25%. Males showed more symmetry of CSA than females. The range of values for symmetry of masseter CSA was too large to assess abnormal asymmetry in patients with unilateral symptoms.

Acoustic myography in the assessment of human masseter muscle

The feasibility of examining electro-mechanical activity of the human masseter muscles using non-invasive recording techniques was examined in six healthy dentate adults (aged 34-57 years). Electrical activity of the muscle was examined by surface electromyography (EMG) and the mechanical activity, in the form of muscle sounds, was examined by acoustic myography (AMG). Bilateral recordings of EMG and AMG were made simultaneously using composite probes which were placed on the skin over the masseter muscles. A standardized pressure was applied to the probes via adjustable rods attached to a safety helmet. Pressures were monitored by strain gauges placed between the ends of the rods and the probes. With the subject seated, recordings of AMG and EMG were obtained during maximal jaw clenching for 4 s and the raw signals were stored on a computer. Of three maximal contractions performed, the last two were used in the analysis. The raw amplified signals underwent frequency analysis by fast Fourier Transform. Total activity was also assessed after amplification, full-wave rectification and integration, and repeatability of the results was assessed. The AMG frequency range was 6-15 Hz and was similar to values for other human skeletal muscles. The integrated values for EMG and AMG were repeatable on both sides of the face (IEMG, right r = 0.99, left r = 0.99; IAMG right r = 0.70, left r = 0.71). Simultaneous recordings of AMG and EMG from the masseter muscles may be useful for assessing electro-mechanical muscle function but further validation studies are required before the technique can be used clinically.

Vasoactive intestinal polypeptide nerve fibers in human and monkey (Macaca fascicularis and Macaca mulatta) kidneys

Nerve fibers immunoreactive for vasoactive intestinal polypeptide (VIP) were demonstrated for the first time by the indirect immunofluorescence technique in human and monkey kidneys. VIP-immunoreactive nerve fibers showing varicosities were observed in the adventitia of arcuate arteries and their branches. The density of VIP-immunoreactive nerve fibers decreased from the juxtamedullary region to the cortex. Occasionally a VIP-immunoreactive varicose nerve fiber was observed near the vascular pole of a glomerulus, but no direct innervation of afferent or efferent arterioles in either monkey or human kidney was found. The distribution of VIP-immunoreactive nerve fibers in the monkey and human kidneys was similar to that reported in other species, with less density. The functional role of VIP in the innervation of the kidney is not known, but various suggestions have been made regarding the possible involvement of VIP on vasodilation of selective intrarenal blood vessels, renin secretion, and/or effects on tubules. While none of these questions were established at this time they would appear to be logical areas for further study.

Anatomy of the reproductive tract of the female muskox (Ovibos moschatus)

Reproductive tracts from 23 female muskoxen were collected from the Canadian high arctic during annual native muskox hunts. Twenty tracts were collected during the late breeding season and the last third of pregnancy or anoestrus, with 3 additional specimens taken just before the breeding season in August. The non-gravid muskox uterus was very similar to that of sheep and goats except for two features found in parous muskoxen. The first was endometrial pigmentation found only in the caruncles and associated with a dense collection of lipofuscin granules in the endometrial stroma. The second was a prominent 5 mm deep band of muscular tissue protruding from the antimesometrial border of the uterine horns throughout most of their length. The pregnant uterus and the fetal membranes of the muskox resembled homologous structures in domestic ruminants. However, there was no morphological evidence of a corpus luteum during late pregnancy, apart from a luteal scar in the ovary ipsilateral to the pregnant horn. Of the 4 females collected at the end of the breeding season, 2 lactating females were apparently not cyclic while 2 others had more than one CL, suggesting that they had undergone at least 2 cycles without conceiving or remaining pregnant.

Measurement of the ascorbate content of spinach leaf protoplasts and chloroplasts during illumination

Protoplasts prepared from spinach leaves in May and June contained substantial amounts of ascorbate (1.33±0.28 μmol mg(-1) chlorophyll), of which 30-40% was localised in the chloroplasts. During illumination, the ascorbate content was maintained at approximately the same concentration as in the dark in both protoplasts and chloroplasts, even in the absence of CO2 when pseudocyclic electron flow would be expected to be maximal. The addition of the Mehler reagent, methyl viologen, to isolated chloroplasts caused a rapid oxidation of stromal ascorbate in the light such that less than 95% of the ascorbate was oxidised after illumination for 1 min. Similarly the stromal ascorbate pool was rapidly oxidised upon the addition of H2O2. We conclude that when the intracellular ascorbate concentration is high, photosynthetically generated H2O2 can be reduced at rates comparable to its synthesis via the ascorbate-glutathione cycle. The addition of methyl viologen which catalyses rapid production of the superoxide anion, O 2 (-) or the addition of excess H2O2, overwhelms the reductive cycle and the ascorbate system becomes partially or totally oxidised.

The effect of sucrose on the rate of de novo sucrose biosynthesis in leaf protoplasts from spinach, wheat and barley

Protoplasts from the leaves of wheat, spinach, and barley were found to synthesize [14C]sucrose from 14CO2 at rates comparable with those of the parent tissue. CO2 fixation and sucrose biosynthesis ceased virtually immediately when the light was switched off. The effect of sucrose pretreatment on the rate of de novo sucrose biosynthesis was found to vary with leaf age and with plant species. Protoplasts from young wheat and spinach leaves showed an apparent stimulation of the rate of sucrose biosynthesis after sucrose pretreatment. In protoplasts from mature leaves of spinach, sucrose pretreatment produced inhibition. After sucrose pretreatment protoplasts from mature spinach leaves showed low rates of CO2 fixation, and sucrose biosynthesis compared with controls. Conversely, with protoplasts from mature leaves of wheat and barley, the rate of CO2 fixation was unchanged and there was little or no effect on the rate of sucrose biosynthesis after sucrose pretreatment. Preincubation with sucrose had no effect on the activity of sucrose-phosphate synthetase (EC 2.4.1.14), cytoplasmic fructose-1,6-bisphosphatase (EC 3.1.3.11), or UDPglucose pyrophosphorylase (EC 2.7.7.9) from spinach leaves. It was concluded that there is no direct feedback inhibition of sucrose on the sucrose biosynthetic pathway in leaves of spinach, wheat, and barley. The mechanism of inhibition of sucrose biosynthesis by sucrose in spinach remains to be elucidated.

Cimetidine: a specific inhibitor of hepatic aryl hydrocarbon hydroxylase (AHH) in the rat

Aryl hydrocarbon hydroxylase was selectively inhibited in hepatic microsomes prepared 2 hours after administration of cimetidine (150 mg/kg, i.p.) to male Wistar rats. Cytochrome P-450 content and other mixed function oxidase activities were not affected. In rats pretreated with phenobarbital or 3-methylcholanthrene, cimetidine caused a 50% and 90% reduction or aryl hydrocarbon hydroxylase activity respectively, compared to 70% inhibition in uninduced animals. Chronic administration of cimetidine (150 mg/kg, b.i.d. for 5 days) to uninduced rats resulted in 70% inhibition of aryl hydrocarbon hydroxylase but no change in other microsomal enzyme activities. Hexobarbital sleeping time was markedly prolonged 30 min after a single dose of cimetidine but had returned to control values after 24 hrs. Similar effects were observed with chronic dosing of cimetidine. It is concluded that in vivo administration of cimetidine is a relatively specific inhibitor of hepatic aryl hydrocarbon hydroxylase in the rat, and that cimetidine does not induce the microsomal mixed function oxidase system when administered chronically.

Some helminth parasites from the small intestine of free-ranging muskoxen Ovibos moschatus (Zimmermann) of Devon and Ellesmere Islands, Northwest Territories

Intestinal contents from two muskoxen, Ovibos moschatus (Zimmermann), collected in March 1978 on Devon Island, N.W.T., both contained Marshallagia marshalli (Ransom 1906) and Nematodirus helvetianus May 1920. Intestinal contents from five muskoxen collected in August 1978 on Ellesmere Island, N.W. T., contained Moniezia expansa (Rudolphi 1810) (one of the five), Ostertagia trifurcata Ransom 1907 (one of five), M. marshalli (one of five) and N. helvetianus (two of five). Cysticerci of Taenia hydatigena Pallas 1766 were found in two of the five animals from Ellesmere Island.